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Products => Test Equipment => Topic started by: torch on February 23, 2013, 05:25:45 pm

Title: $20 LCR ESR Transistor checker project
Post by: torch on February 23, 2013, 05:25:45 pm
A few weeks ago I stumbled over this fellow on fleabay:

(http://picturehosting.verhey.org/lcr/lcr.JPG).

What the heck, for $20 it looked like it could be fun, especially for a dilettante like me with a drawer full of oddball small signal mystery transistors. I put it in a project box, added some leads and a switch and hooked up a 9v battery.  Operation is simple: connect the component (leads in any order),  push test. It tells you what it is and the value:

A 1% resistor:

(http://picturehosting.verhey.org/lcr/resistor.jpg)

A capacitor (this one must have real low ESR -- usually there's a value in ohms):

(http://picturehosting.verhey.org/lcr/capacitor.jpg)

A transistor (note that it tells you if it's PNP or NPN and which lead is connected to what, gain and forward voltage):

(http://picturehosting.verhey.org/lcr/transistor.jpg)

How about an inductive load?

(http://picturehosting.verhey.org/lcr/coil.jpg)

FAIL! That's an IGBT, not a capacitor. (To be fair, it's rated 600v/40amps):

(http://picturehosting.verhey.org/lcr/IGBT.jpg)

Partial Fail. This is a power transistor, not a pair of diodes. Oh well, at least I can figure out from that if it's PNP or NPN:

(http:///picturehosting.verhey.org/lcr/power_transistor.jpg)

FAIL again -- Ooops, no it's not. My mistake. That really IS a diode that got mixed in with the SCRs -- look at the number:

(http://picturehosting.verhey.org/lcr/Diode.jpg)

Ok, here's a real SCR (GAC indicates which lead connected to the Gate, Anode and Cathode, respectively):

(http://picturehosting.verhey.org/lcr/SCR.jpg)

But an LM317 threw it for a loop:

(http://picturehosting.verhey.org/lcr/LM317.jpg)

The documentation is non-existent. I accidentally discovered a self-test/calibration mode by connecting all 3 leads to each other and pushing the button. On-screen directions kind of guide you through each numbered step if you scratch your head long enough deciphering them. A 100nF capacitor is required at one point (step 4, IIRC).

Anyway, a cute little gizmo, certainly worth the $20 and it seems reasonably accurate within the scope of it's limitations.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Lightages on February 23, 2013, 05:34:17 pm
Could you give a few more capacitors a try to see if it actually can measure ESR. What is the test voltage for capacitors?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Analogtech on February 23, 2013, 06:17:31 pm
I remember seeing the exact same thing on eirik Taylors blog on 4hv. It had pretty good documentation and test results on it so you might want to go check that out
Title: Re: $20 LCR ESR Transistor checker project
Post by: Lightages on February 23, 2013, 06:43:10 pm
I looked for the review or blog and got nowhere. A link please?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Analogtech on February 23, 2013, 07:09:33 pm
http://uzzors2k.4hv.org/index.php?page=lcfmeter (http://uzzors2k.4hv.org/index.php?page=lcfmeter) that's the link to the blog
Title: Re: $20 LCR ESR Transistor checker project
Post by: fmaimon on February 23, 2013, 07:45:24 pm
http://www.mikrocontroller.net/articles/AVR_Transistortester (http://www.mikrocontroller.net/articles/AVR_Transistortester)
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on February 23, 2013, 08:06:47 pm
Could you give a few more capacitors a try to see if it actually can measure ESR. What is the test voltage for capacitors?

What, don't believe me???? <lol>

I am not sure what the test voltage is for capacitors, I looked at the test sequence on a scope and it sends out a lot of little pulses on the leads, and which does what is beyond my ken. However, the highest voltage seems to be about 3.5v or thereabouts near the end of the sequence with a capacitor attached.

And actually, your question is a fair one because there seems to be a cut-off between 1uf and 2uf below which it does not attempt to measure ESR. Here are some photos as proof:
 
Here's a 10uf capacitor:

(http://picturehosting.verhey.org/lcr/01_10uf.jpg)

and here's a 1% 1 ohm resistor:

(http://picturehosting.verhey.org/lcr/02_1_ohm.jpg)

Here they are in series:

(http://picturehosting.verhey.org/lcr/03_esr+resistor.jpg)


I didn't have a 1uf capacitor, so here's two 2.2 in series. No ESR value shown:

(http://picturehosting.verhey.org/lcr/04_1.1uf.jpg)

But a 2.2uf alone is measured for ESR:

(http://picturehosting.verhey.org/lcr/05_2.2uf.jpg)

A 1000uf can has a really low ESR:

(http://picturehosting.verhey.org/lcr/06_1000uf.jpg)

And here's a few random used cardboard electrolytics, for fun:

(http://picturehosting.verhey.org/lcr/07_old_paper1.jpg)

(http://picturehosting.verhey.org/lcr/08_old_paper2.jpg)

(http://picturehosting.verhey.org/lcr/09_old_paper3.jpg)

I had a quick look at that blog link. It may have been the genesis of this one, but it's certainly not the same thing.   







Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on February 23, 2013, 08:16:34 pm
Ok, the first link may not be the same thing, but the second one sure sounds like it. I think. It's in German, but here's google's translation effort:

http://translate.google.ca/translate?sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&eotf=1&u=http%3A%2F%2Fwww.mikrocontroller.net%2Farticles%2FAVR-Transistortester (http://translate.google.ca/translate?sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&eotf=1&u=http%3A%2F%2Fwww.mikrocontroller.net%2Farticles%2FAVR-Transistortester)
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on February 24, 2013, 01:30:47 am
I got one of these too - they are a lot of fun. The component values are usually within 1%. Does a pretty good job correctly identifying transistors, diodes, etc.

I did try a tough test  - a RCA 2N3669 thyristor and it identifier it as a 33 ohm resistor. This is not surprising as there is a built in 33 ohm resistor from gate to cathode. It found the resistor and didn't look any further I guess.

Not sure how good it is as an ERS meter. I am not going to do any proper tests now. If I short two inputs together, I get 0.2 ohms and there is nothing to cancel this out. The best accuracy you could expect is 0.1 ohms even though the software calculates ESR to 2 places.

If I get to fiddle with the software, a feature to force it to test in one mode (resistance, capacitance, inductance, etc) could be good. As a single button tester, it is not bad at all.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on February 24, 2013, 02:39:47 am
If I short two inputs together, I get 0.2 ohms and there is nothing to cancel this out. The best accuracy you could expect is 0.1 ohms even though the software calculates ESR to 2 places.

If you short all 3 it will go into the self-calibration mode and then it will read 0 ohms when you short 2 leads together. Just make sure you have a 100nF capacitor handy and follow the prompts or it will eventually read 33pF when you short 1 and 3. Don't Ask Me How I Know This(tm).  :scared:

I went through that damn routine more than once before I figured it out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on February 24, 2013, 03:18:43 am
If you short all 3 it will go into the self-calibration mode and then it will read 0 ohms when you short 2 leads together. Just make sure you have a 100nF capacitor handy and follow the prompts or it will eventually read 33pF when you short 1 and 3. Don't Ask Me How I Know This(tm).  :scared:

I went through that damn routine more than once before I figured it out.
Wow - I just did it (including the 0.1uF 0.5% cap) and it does do the self-calibration test. Who needs metrology labs?

After calibration, a short went down to 0.1 ohms, but to be fair, the wires I was using to short the pins for the calibration were not the best.

Looks like they use a 2V zener in series with 2k2 from a 5V regulator. That will not be very stable. I think the original circuit used a LT reference IC instead. I wonder how it calibrates its voltage reference?

Update: After the calibration, I now get 35P between pins 2 and 3 with nothing connected. I better read up on the calibration.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ecat on February 24, 2013, 03:20:47 am
Ok, the first link may not be the same thing, but the second one sure sounds like it. I think. It's in German, but here's google's translation effort:

http://translate.google.ca/translate?sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&eotf=1&u=http%3A%2F%2Fwww.mikrocontroller.net%2Farticles%2FAVR-Transistortester (http://translate.google.ca/translate?sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&eotf=1&u=http%3A%2F%2Fwww.mikrocontroller.net%2Farticles%2FAVR-Transistortester)

That is the original by Markus Frejek.


This is the modified version courtesy of  Karl-Heinz Kübbeler...

http://translate.google.com/translate?hl=en&sl=de&u=http://www.mikrocontroller.net/articles/AVR_Transistortester&prev=/search%3Fq%3Dtransistortester.tar.gz%26hl%3Den%26safe%3Doff%26client%3Dfirefox-a%26hs%3DILT%26rls%3Dorg.mozilla:en-GB:official&sa=X&ei=PYQpUbfWMenD0QWrn4GQCg&ved=0CFMQ7gEwBA (http://translate.google.com/translate?hl=en&sl=de&u=http://www.mikrocontroller.net/articles/AVR_Transistortester&prev=/search%3Fq%3Dtransistortester.tar.gz%26hl%3Den%26safe%3Doff%26client%3Dfirefox-a%26hs%3DILT%26rls%3Dorg.mozilla:en-GB:official&sa=X&ei=PYQpUbfWMenD0QWrn4GQCg&ved=0CFMQ7gEwBA)

... see Download for a link to the full source + comprehensive documentation.


I built one last week, the fun part was persuading an Arduino to do the job of an AVR programmer :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on February 24, 2013, 03:55:40 am
Here is the most recent PDF for the tester, including information about the chinese clones. I have to say it is a really great manual.

You are meant to replace the zener with a decent reference.

In the self calibration, the shorted inputs should be removed during test 4. When this is done, the tester works properly again.

The V2.2 board I got has a JTAG 10 pin ISP port and a ATMEGA168 (with the part number rubbed off) and apparently it works fine if updated to the latest software. Mine came with software version 105k. Karl Heinz's's latest version is 106k. I will give it a go sometime.

There are some additions that can be done. One is a circuit to generate up to 30VDC for measuring zener breakdown voltage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ecat on February 24, 2013, 05:50:17 am
Just tested the accuracy of my home made version.

A 0.01% 5k resistor reads 5066, so about 1.3% which is good enough for a quick test. I matched the 680r and 470k resistors to the third digit, maybe better matching would help.

Still, a nice little project if you have a way to program up a Mega328. I've attached the Eagle 6.3.0 files for my single sided diy version of Karl-Heinz Kubbeler V1.06k if anyone is interested. I do not claim any competence with schematics or board layout so use at your own risk :)

Board Notes:
The two jumper wires are optional.

You probably don't need the 5V jumper wire to the program header. Even if you program the 328 in circuit just make sure the board is powered by keeping SW1 closed. You should always try to avoid supplying power to a circuit from both the board and your programming device, this is not be a good thing as you should never let the beams cross ;).

The Reset jumper wire is needed if you program in circuit. If you program the 328 out of circuit you can ignore this jumper and the 6 pin header.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on February 24, 2013, 12:44:43 pm
Here is the most recent PDF for the tester, including information about the chinese clones. I have to say it is a really great manual.

That PDF you found  is great! I have only skimmed it thus far, but it does cover a lot of territory.  I too have the "2.2" version, and I note that he describes a potential problem with zeroing the resistance test if the 2.2 is updated to the latest software (1.06):

Quote
"The printed circuit board track from the ATmega168 to the test port is very thin, so that a resistance of 100m
 could be measured for one path. This will be the reason for measuring a resistance of 0:3  for two direct connected pins. The ESR measuring can usually consider this by zero compensation. The current version of software does not respect this off set for measuring of resistors with low resistance."

I also found the explanation of why I had an ESR of "0?" in that first capacitor:
Quote
"with the AUTOSCALE ADC option. The zero o set for the ESR measurement will be preset with the option ESR ZERO in the Make le. This zero o set, which is set too high in normal case, will be preset in EEprom by the software. With every selftest the ESR zero o set will be reset to this initial value. After every ESR measurement the result will be checked for negative value (output of "ESR=0?"). In this case the zero o set will be reduced to get a zero result for next ESR measurement. With this methode the zero o set can be adjusted with a electrolytical capacitor with high capacity value and low ESR value. This learned ESR zero o set remains active after power o , but the adjust procedure to get the zero o set of ESR measurement must be done after every selftest and in this case you should always repeat the measurement some times."

I won't quote the entire section on how the ESR is done. However, the doc confirms that the device will only determine ESR for caps over 2uF. I suspect this is because the frequency is only 680Hz instead of the more traditional 100MHz. Apparently it repeats the test 128 times and sums the values to derive the final answer, but he cautions that the ESR test is not to be considered accurate compared to a dedicated ESR meter.

It is interesting to note the effort that has gone into adjusting the capacitance measurement accuracy. Again, I was just skimming, but he seems to have done some extensive testing of the raw capabilities compared to an LCR meter and a multimeter, (looks like the native ATmega results fell between the two) then formulated some correction factors to bring the results closer in line to the LCR results.

A lot of thought and effort went into this little thing -- on his part, anyway. The Chinese just copied and mass produced.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on February 24, 2013, 01:29:06 pm
This transistor tester is a masterclass in making use of the internal hardware of an atmega. The internal analog switch resistances are measured, the internal comparitor offset is measured. The hardware is used in many different modes to achieve a result. Brilliant. It is all much more sophisticated then I was expecting.

By using 3 ports per test pin each along with two precision resistors, the effective total of test hardware per pin is 9 resistors, 3 three position single pole switches (to GND, VCC and open circuit), three comparitors and one ADC. The ADC is switched between different references

The thing you realize is that the quality of the hardware embedded in the atmega IC is very good.

When you do the self calibrate, it outputs the calibration factors that also indicate something about the hardware.

For example test 7 checks the ratios of the 470K and 680 ohm resistors to the expected. They were meant to be 0.1% resistors, so the match should be good. In my tester, the errors were 1 mv for each of the three resistor pairs. It does look like the Chinese did actually use 0.1% SMD resistors. I know my 680 ohm resistors match within 0.1%, but I cannot measure the 470K resistors accurately in circuit.

I think they would love to build this with a chip with a better A/D, but a 5V chip is required - the lower voltage chips don't work as well for semiconductor testing.

I love it when someone wrings every bit of performance out of a piece of hardware, and that is exactly what is done in this transistor tester project. They admit somethings are not optimal yet, and there are some errors they cannot yet explain, but they are continually improving the design.

A very good project.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on February 24, 2013, 01:38:10 pm
Well, yes, this little tester is a fine project with lots of effort put into it!

This is the current discussion thread of this project in German, with a vivid presence of the author of that port of the project, Karl-Heinz Kübbeler:
http://www.mikrocontroller.net/topic/248078#2950824 (http://www.mikrocontroller.net/topic/248078#2950824)

Unfortunately, http://translate.google.com/ (http://translate.google.com/) cannot handle such long threads but it is more than sufficient to translate individual posts.

This is also the project's source code archive:
http://www.mikrocontroller.net/svnbrowser/transistortester/ (http://www.mikrocontroller.net/svnbrowser/transistortester/)

If I manage to find some time to spare I will rewrite this project in assembly, in order to speed things up a little bit by avoiding the C compiler bloating. If I am not mistaken, the current version of the code (v1.06k) does not take into consideration the hardware ADC offset by initially measuring it and subtracting it from every ADC result; this would certainly improve the overall tester accuracy.


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on February 24, 2013, 02:12:59 pm
If I am not mistaken, the current version of the code (v1.06k) does not take into consideration the hardware ADC offset by initially measuring it and subtracting it from every ADC result; this would certainly improve the overall tester accuracy.

You have obviously got further then me. I have only spent a couple of hours with the manual. I particularly want to work through some of the measurements like the ESR in detail.

I would have though that the calibration factors that they measure and store would cancel out the ADC offsets. I cannot see any reason to correct every ADC result, when you can correct once at the end instead. I am definitely not discounting your point - I haven't looked at the calculations to see what effect errors at the start would have on the final result. It could be better to correct every reading.

I just looked at the data sheet and it looks like the total error in the ADC, including offset and non-linearity is about 0.2% with a 200KHz clock rising to about 0.5% with a 1MHz clock.

A complete correction of the ADC linearity and errors using our PWM voltage source would be interesting. That would need some great assembler coding for speed. It would probably at best double the accuracy but the hardware cost would be a few caps, resistors and another test connection to output the PWM. And time.

Richard.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on February 24, 2013, 02:34:53 pm
Ah no, Richard, I have not really studied the project in that depth of detail! I've just had a quick look at its source code and I noticed that omission.

Now, on the self canceling out of the ADC errors, yes, theoretically it would work; but I cannot see any reason why not to subtract from the ADC results any measured possible offset, which varies from -2 .. +2 LSB according to the data sheets. Especially, when those possible errors accumulate by oversampling. Of course, summing readings that are taken both ways (positive and negative) would cancel out those unwanted accumulated quantities. My point is that it would not hurt to try this out and compare the results.


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on February 24, 2013, 03:34:48 pm
Damn, both of you Richard and George have made me to put this thread in one of my top watch list.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on February 24, 2013, 06:57:01 pm
Yeah, it is starting to look like this thread is taking on a life of it's own, doesn't it?   ;D

I don't seem to have any caps above 1000uf available, so I started stringing them together. The ESR value is definitely self-calibrating depending upon the highest capacitance it has measured. Adding each successive capacitor, the ESR is shown as 0? on the first test or two, then settles around .01 to .03 ohms. Testing a control cap, the indicated ESR climbs slightly each time the baseline is set. I got up to ~7200uF and the control went from 0.01ohms to 0.12ohms. Actually, there is about .02 ohms variability there -- pushing the test button repeatedly without disturbing the leads at all will result in successive readings between 0.11 and 0.13 ohms.

So don't take the ESR figure as gospel. It's really a comparison with the ESR of the largest cap it has previously encountered (since the last self-test/calibration) considered as 0.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 24, 2013, 08:45:35 pm
If I manage to find some time to spare I will rewrite this project in assembly, in order to speed things up a little bit by avoiding the C compiler bloating. If I am not mistaken, the current version of the code (v1.06k) does not take into consideration the hardware ADC offset by initially measuring it and subtracting it from every ADC result; this would certainly improve the overall tester accuracy.

Actually, speed is no concern since a lot of the time the firmware has to wait, e.g. for the ADC. There's also no gain from changing the crystal from 8 to 16 MHz; a faster ADC would help. A zero offset of the ADC was already discussed and the idea was dropped. A changing offset (=noise) helps with the oversampling.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Spawn on February 24, 2013, 10:17:45 pm
Damn, both of you Richard and George have made me to put this thread in one of my top watch list.  :-+

+1  I am with BravoV, nice job with documenting guys :)  And thanks for the measurements Torch.
I ordered one a week ago, might build a case for it too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on February 25, 2013, 03:56:30 am
+1  I am with BravoV, nice job with documenting guys :)  And thanks for the measurements Torch.
I ordered one a week ago, might build a case for it too.

Ok, that makes me think:

I'm involved with mentoring the local high school's robotic's club (don't worry, not the electronics, I help out with machining the mechanical bits!  ;) ). Anyway, they are looking for some fundraising ideas. They have a PVC 3d printer in the shop class. Would there be any interest in having cases made for these? Maybe a kit with the leads, shielded bannana plugs and clips included? And a separate battery compartment. I would definitely want a separate battery compartment. What other features would you look for and how much would something like that be worth to you?
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on February 25, 2013, 04:19:21 am
Yeah, it is starting to look like this thread is taking on a life of it's own, doesn't it?   ;D
This two kind gentlemen are well known to generate a really excellent discussion when they're "in-sync"  ;) with each other at the same topic similar at this one here.

Here an example at the topic on generating an adjustable + high resolution voltage reference using cheapo components -> Amspire's thread : General Purpose Power Supply Design (https://www.eevblog.com/forum/projects/general-purpose-power-supply-design-7488/). Imo it is one of the best among finest threads in this forum, just take a cup of coffee and read it your self, its a long thread.  :P  Too bad that project is on hold.  :'(

Ok, enough OOT, I bet you've got my point. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on February 25, 2013, 06:04:09 am
[...]
Too bad that project is on hold.  :'(
Any decent designer ought to have a handful of projects on hold! :P
I mean that, giving birth to an idea does not necessarily mean that spiritual inspiration can be switched ON and OFF on demand; there will always be lots of other variables in the way...
Thank you for your kind words!


Actually, speed is no concern since a lot of the time the firmware has to wait, e.g. for the ADC. There's also no gain from changing the crystal from 8 to 16 MHz; a faster ADC would help. A zero offset of the ADC was already discussed and the idea was dropped. A changing offset (=noise) helps with the oversampling.
Thank you for the information.

If I am not mistaken, I can see that you are Markus (https://www.eevblog.com/forum/testgear/$20-esr-lcr-transistor-npn-pnp-mosfet-meter/msg188659/#msg188659), the author of the current -m versions along with Karl-Heinz's -k ones! Firstly, let me congratulate you both for your efforts.

I am familiar with oversampling and the decimation/averaging method of achieving higher resolutions as well as with the (random) noise injection method of a few LSBs into the under test signal, in order to assist oversampling. I also agree in that the standard 8-bit AVR ADC might be insufficient for any faster or any better accuracy results than those already achieved, since its non-linearity and gain errors put a ceiling to the final acquisition product maximum resolution accuracy.

Now, it is a fact that even 1 LSB offset error narrows down the usable range of the 1024 discrete steps of the 10-bit ADC available output by one unit, affecting the final product value by introducing a minor scaling error. Is this the reason why the ADC results offset corrections were overruled? Because, during the auto-calibration procedure, the offset error can be measured, compensated, and it can be used for the calculation of the usable ADC range; and all these additional ADC parameters can be also stored in EEPROM along with the other device parameters.


A complete correction of the ADC linearity and errors using our PWM voltage source would be interesting. That would need some great assembler coding for speed. It would probably at best double the accuracy but the hardware cost would be a few caps, resistors and another test connection to output the PWM. And time.
I really like your idea, Richard!

Changing dynamically the voltage reference by the use of the available PWM hardware might breathe new life into this already impressive project, by expanding dramatically the device's dynamic range. Of course, any fancy hardware changes will be a problem to the existing standard devices, which will not be able to make use of any possible new features without any PCB/hardware (heavy) modifications.

Other than that, and based on the latest Component Tester schematics, any of the PC5:PC3 spare I/O lines could be exchanged with PB1 (or PB2) in order to take advantage of the OC1A (or the OC1B) 16-bit PWM outputs (https://www.eevblog.com/forum/projects/general-purpose-power-supply-design-7488/msg103985/#msg103985) (with a sub-millivolt resolution!); another ADC line of the spare ones (PC6:PC3) is needed to be driven by the configurable PWM voltage reference generated (through an additional RC low-pass filter). The external crystal should not be dropped (in order to utilise the PB7:PB6 I/O lines) because it would impair the time-based measurements accuracy. The only drawback I can see is the additional time needed (in the order of a couple of hundreds of milliseconds) for the PWM output RC filter to reach its final output before it can be used as a stable voltage reference. As a bonus, the very low level ripple induced by the PWM stage will assist oversampling.

Unfortunately, the m168/m328 ADC does not support differential channels input, nor the relatively high impedance PWM stage RC filter output can drive directly the 32 Kohm AREF input line without any external buffering; but this error can be measured and compensated if this configuration is chosen to be used.


In a few words, the improvements potential of this project seems to be promising! I guess that I will have to build a device (or order a chineese copycat) for any further experimentation...


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on February 25, 2013, 08:39:32 am
I would prefer an SPI/I2C driven, precision DAC. Don't know if the pin count allows it. Maybe shared with the LCD.

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on February 25, 2013, 08:51:37 am
I would prefer an SPI/I2C driven, precision DAC. Don't know if the pin count allows it. Maybe shared with the LCD.

Alexander.

I believe they're opening up the challenge not to touch the hardware design, all will be done purely at software to improve this circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on February 25, 2013, 08:58:22 am
They will have toy use capacitors and resistor for the PWM filter. Just joking!

A DAC could be just bodged to the main pcb. I might give it a try my self.

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 25, 2013, 11:42:05 am
If I am not mistaken, I can see that you are Markus (https://www.eevblog.com/forum/testgear/$20-esr-lcr-transistor-npn-pnp-mosfet-meter/msg188659/#msg188659), the author of the current -m versions along with Karl-Heinz's -k ones! Firstly, let me congratulate you both for your efforts.

Thanks! You're welcome! I forwarded the URL of this thread to Karl-Heinz, so he can enjoy this too ;-)

Quote
Now, it is a fact that even 1 LSB offset error narrows down the usable range of the 1024 discrete steps of the 10-bit ADC available output by one unit, affecting the final product value by introducing a minor scaling error. Is this the reason why the ADC results offset corrections were overruled? Because, during the auto-calibration procedure, the offset error can be measured, compensated, and it can be used for the calculation of the usable ADC range; and all these additional ADC parameters can be also stored in EEPROM along with the other device parameters.

Karl-Heinz tested a lot of ATmegas (same and different models) and none showed any large offset for the internal 10 bit ADC. Surely, the offset has an impact on the result but it's quite low based on the findings. The ADC measurements are done in a tiered way. The first measurement uses 5V as reference voltage and if the result is below the internal bandgap reference (about 1.1V for the more powerful ATmegas) the measurement is repeated using the bandgap reference. The accuracy of that bandgap reference (about 10%) causes much more trouble than a low ADC offset. Of course the voltage of the bandgap reference is measured, but using 5V as reference for that doesn't give a high accuracy either. Karl-Heinz' firmware version supports an optional external voltage reference of 2.5V to improve the accuracy.

Quote
Changing dynamically the voltage reference by the use of the available PWM hardware might breathe new life into this already impressive project, by expanding dramatically the device's dynamic range. Of course, any fancy hardware changes will be a problem to the existing standard devices, which will not be able to make use of any possible new features without any PCB/hardware (heavy) modifications.

One of the projects main goals is to support the classic transistor tester design because a lot of people built that. There's more value in improving and extending the firmware than in upgrading the hardware every few months for a OSHW project. BTW, there are two hardware extensions, which are compatible with the current design. One is a relay to discharge caps with voltages above 5V and the other is a high voltage addon for zehner diodes. AFAIK we'll keep it that way until we hit the nothing-can-be-improved-anymore mark. When that happens there might be a Tester+. I'll note your ideas and suggestions ;-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Telstar on February 25, 2013, 01:27:59 pm
very nice project!
At first i thought it was a clone of the Peak Electronic testers but then I think it's something different and with more functions than any of their devices taken alone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on February 25, 2013, 01:32:02 pm
Changing dynamically the voltage reference by the use of the available PWM hardware might breathe new life into this already impressive project, by expanding dramatically the device's dynamic range. Of course, any fancy hardware changes will be a problem to the existing standard devices, which will not be able to make use of any possible new features without any PCB/hardware (heavy) modifications.

One of the projects main goals is to support the classic transistor tester design because a lot of people built that. There's more value in improving and extending the firmware than in upgrading the hardware every few months for a OSHW project. BTW, there are two hardware extensions, which are compatible with the current design. One is a relay to discharge caps with voltages above 5V and the other is a high voltage addon for zehner diodes. AFAIK we'll keep it that way until we hit the nothing-can-be-improved-anymore mark. When that happens there might be a Tester+. I'll note your ideas and suggestions ;-)
Markus, great to see you in this forum. I just find the efforts of you and Karl-Heinz inspiring. You have used the Atmega processors in ways I never even considered, and it is exciting.

I do understand that your project is all about very simple hardware, and making improvements through firmware, but you may be interested in the work George (A Hellene) and I did on the Atmega PWM as a voltage divider/reference.

To summarize, what we found was that you can get extremely impressive precision and resolution using the 8 bit PWM - the performance was a long way superior to the 16 bit PWM. This means that the processor can output two precision voltages or divider ratios at resolutions up to 24 bit with less then a second settling time with a few lines of code. Hardware is as little as three 5% resistors and three multilayer ceramic capacitors per reference output.

One of the things I found was that for precision circuits, use the full swing clock for a ceramic resonator, not the low power one. The full swing clock is noise insensitive and the jitter appears to be less then 1nS even on a breadboard. The lower power clock has more of jitter and it is very sensitive to modulation from nearby electrical noise - particularly LCD displays. Going from a low power clock to the high power clock probably improved the PWM linearity by a factor of over 10 on a breadboard test. I didn't test to see if a crystal instead of a ceramic resonator has the same issues, but there may well be some degradation.

If you are interested, take a look at this post first. When I did this test, I was going to be happy if I achieved better then 1% accuracy:

https://www.eevblog.com/forum/projects/general-purpose-power-supply-design-7488/150/ (https://www.eevblog.com/forum/projects/general-purpose-power-supply-design-7488/150/)

If that gets you interested, then the first relevant post is here:

https://www.eevblog.com/forum/projects/general-purpose-power-supply-design-7488/msg99807/#msg99807 (https://www.eevblog.com/forum/projects/general-purpose-power-supply-design-7488/msg99807/#msg99807)

It is a long thread unfortunately.

The idea started from the need for a very high resolution and very cheap reference source for voltage and current for a low cost power supply. I wanted to be able to monotonically adjust voltage down to about 10uV steps so I could use the supply for tasks like providing the DC voltage input to a Fluke 540B RMS calibrator. For that an adjustable DC source is needed that is stable and can be adjusted down to the 0.001% level resolution. Accuracy wasn't important, but I was shocked to how good the Atmega PWM was. Most modern digital power supplies do not have the resolution.

Thanks to you, I now I find it is not the only magic that you can do with an Atmega processor.

Richard.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on February 25, 2013, 04:28:24 pm

Thanks! You're welcome! I forwarded the URL of this thread to Karl-Heinz, so he can enjoy this too ;-)


Markus and Karl-Heinz,-

When I stumbled on this Chinese-made gizmo, I had no idea of  the history and background behind it. Reading all of the above (and the documentation) I realize now what a truly impressive project this is and I thank you for all your efforts. Beyond the ingenuity of squeezing so much out of a processor that wasn't purpose-built for the task, the end result is a very useful tool in and of itself. I will have to explore further the two enhancements (cap discharge and zener diode) that you mention.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Spawn on February 25, 2013, 05:56:54 pm
Maybe a kit with the leads, shielded bannana plugs and clips included? And a separate battery compartment. I would definitely want a separate battery compartment. What other features would you look for and how much would something like that be worth to you?

Torch, thanks for the heads up, I would like to build one myself, it is fun for me to do so. Right now I ordered some parts for my DMMCheck, I mailed with the maker (Doug) to have some ideas so I don’t make something which makes the DMMCheck go out spec.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 25, 2013, 06:59:27 pm
If you are interested, take a look at this post first. When I did this test, I was going to be happy if I achieved better then 1% accuracy:

https://www.eevblog.com/forum/projects/general-purpose-power-supply-design-7488/150/ (https://www.eevblog.com/forum/projects/general-purpose-power-supply-design-7488/150/)

If that gets you interested, then the first relevant post is here:

https://www.eevblog.com/forum/projects/general-purpose-power-supply-design-7488/msg99807/#msg99807 (https://www.eevblog.com/forum/projects/general-purpose-power-supply-design-7488/msg99807/#msg99807)

It is a long thread unfortunately.

That's also a great project! The idea to generate a MCU driven adjustable voltage reference to optimize accuracy and resolution for low voltages is compelling. Much better than the internal bandgap reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Spawn on March 07, 2013, 09:35:53 pm
I received my tester today, I measured couple resistors and capacitors and this is little fun device to play with. I am not sure how the accuracy is but known values looks okay, and that is not that important at this price.

Now I need some time to make a case for it. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: -DOM- on March 15, 2013, 03:19:50 am
I read elsewhere on the forums that this doesnt support in circuit esr readings. Have you tried? I am not after a super accurate measurement just to tell if a cap is bad.

Once i have done enough repairs i hope to by a proper tester although i just cant justify it at this stage.

cheers damien
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on March 15, 2013, 04:44:18 am
Spawn, please, share the scope's shot on the measuring signals at the probe from open connection to different DUTs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on March 15, 2013, 06:11:05 am
I read elsewhere on the forums that this doesnt support in circuit esr readings. Have you tried? I am not after a super accurate measurement just to tell if a cap is bad.
No - you would definitely be much better off using a meter designed for ESR measuring at 100kHz. You cannot even force the ESR to tests the attached device as a capacitor - it makes a best guess, and who knows what guess it will come up with in an in-circuit test. It also has zero protection and trying to add protection any interfere with other device readings. A good ESR meter will hopefully have some ability to survive some residual charge on a capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on March 15, 2013, 06:41:15 am
No - you would definitely be much better off using a meter designed for ESR measuring at 100kHz.
Why Richard ? Is that because of common power caps are rated at 100Khz ? or other reasons ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on March 15, 2013, 06:47:59 am
No - you would definitely be much better off using a meter designed for ESR measuring at 100kHz.
Why Richard ? Is that because of common power caps are rated at 100Khz ? or other reasons ?
Because at 100kHz, the ESR resistance is much larger then the impedance due to the capacitance so it is easy to measure the ESR accurately. For example a 100uF cap has 16 milliohms impedance due to the capacitance. A 2000uF cap has less then 1 milliohm due to the capacitance and that is about the resolution limit of the best in-circuit esr meters. It is really easy to see a 20 milliohm esr when it is in series with 1 milliohm capacitive impedance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on March 15, 2013, 06:55:58 am
No - you would definitely be much better off using a meter designed for ESR measuring at 100kHz.
Why Richard ? Is that because of common power caps are rated at 100Khz ? or other reasons ?
Because at 100kHz, the ESR resistance is much larger then the impedance due to the capacitance so it is easy to measure the ESR accurately. For example a 100uF cap has 16 milliohms impedance due to the capacitance. A 2000uF cap has less then 1 milliohm due to the capacitance and that is about the resolution limit of the best in-circuit esr meters. It is really easy to see a 20 milliohm esr when it is in series with 1 milliohm capacitive impedance.
Thanks, noted.  :-+

Ok, a bit offtopic, but this times about the "circuit design", is there any significant "challenge" to design/make the LCR measurement circuit that capable of max 100KHz vs 10KHz ? Or other non technical concerns maybe ?

Cause at commercial LCR meters, the price difference is quite significant, why is that ?  ???
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on March 15, 2013, 07:14:11 am
Ok, a bit offtopic, but this times about the "circuit design", is there any significant "challenge" to design/make the LCR measurement circuit that capable of max 100KHz vs 10KHz ? Or other non technical concerns maybe ?

Cause at commercial LCR meters, the price difference is quite significant, why is that ?  ???
It is simply that there are many sources of error, particularly at 100kHz, the designers have to track each one down and see what they can do to reduce or eliminate that source of error. Sometimes they can find a way for the software to measure the internal error, and eliminate it from the result through calculation. Sometimes it just means lots of PCB layout revisions. Sometimes very small changes in design make a big improvement in accuracy. It can mean trying just about every analog switch on the market to find the one that performs the best.

So the difference between an top Agilent meter, and a cheap no-name Chinese one is the amount of time the designers spend polishing the design. The cheap one is probably a close copy of a chipsets manufacturer's sample circuit, or closely based on another company's design - but without the knowledge that that other company had in optimizing the performance.

Even though a final circuit can look reasonably simple, the chances of one of us designing a meter to equal an Agilent one on a first attempt is pretty low.

Then again, you never know if you don't try.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on March 15, 2013, 07:18:43 am
Got it, great knowledge learned here ! Thanks again !  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Spawn on March 15, 2013, 11:51:21 am
Spawn, please, share the scope's shot on the measuring signals at the probe from open connection to different DUTs.

I don’t have DSO BravoV but I got a CRO with digital storage so I can take picture of it, what values do you want me to measure? I got most common capacitors ceramic and electrolytic and I can compare it to my crappy UT603 if you want  ^-^
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on March 15, 2013, 12:47:25 pm
I don’t have DSO BravoV but I got a CRO with digital storage so I can take picture of it, what values do you want me to measure? I got most common capacitors ceramic and electrolytic and I can compare it to my crappy UT603 if you want  ^-^
1st is open connection, no DUT, straight from the test probes, 2nd a known low esr cap, and last that low esr cap series with a resistor or a known high esr cap. Really appreciate and thanks for trouble.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on March 15, 2013, 01:12:02 pm
No - you would definitely be much better off using a meter designed for ESR measuring at 100kHz. You cannot even force the ESR to tests the attached device as a capacitor - it makes a best guess, and who knows what guess it will come up with in an in-circuit test. It also has zero protection and trying to add protection any interfere with other device readings. A good ESR meter will hopefully have some ability to survive some residual charge on a capacitor.

With a frequency of 680Hz, this device is limited in it's ability to test low value caps even out of circuit. I think it's OK for most electrolytic caps though. Provided it picks up the DUT as a cap, and provided the cap is discharged, and provided the cap is within the appropriate range, I don't see any reason why it can't work in-circuit as compared to a dedicated ESR meter.

As for protection, I wonder if a simple NC relay would suffice for some measure of protection? If the relay contacts were opened by the power-on sequence, they would discharge the cap on connecting the leads then effectively drop out of the circuit when the test button was pushed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Spawn on March 15, 2013, 06:51:21 pm
1st is open connection, no DUT, straight from the test probes, 2nd a known low esr cap, and last that low esr cap series with a resistor or a known high esr cap. Really appreciate and thanks for trouble.  :-+

Okay  :-+ I will do that in a bit, don’t have caps with known ESR value but I will figure out something.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Spawn on March 15, 2013, 10:08:57 pm
Okay BravoV, this thing is doing weird stuff  :-DD

Trying capture anything with a 4k storage was a real task, I could only capture in magnified sec/div at 5nS but the thing is this tester puts out different waveforms till it can measure and I could only capture the last one and the frequency of these are really odd. I think a DSO with proper storage could see a lot more. Maybe someone with a decent scope can help us?

Directly probed on the test inputs puts out 100MHz, which is weird and it also measures the input resistance of the scope with 9762kohm:
(http://i193.photobucket.com/albums/z298/Bl4ckW0lfi3/empty_test_zps8e88f78a.jpg)

Another weird measurement, with 100uF 20% cap, my scope couldn’t measure one or two waves so I grabbed 3 waves and it reads 0.0833GHz, LCR tester reads 2.7ohms:
(http://i193.photobucket.com/albums/z298/Bl4ckW0lfi3/100uF_27esr_cap_zps5c9d0052.jpg)

Here testing 10ohm resistor, while testing this LCR tester knows it is a resistor and it doesn’t put out any frequency, the wave on scope is from last measurement with cap:
(http://i193.photobucket.com/albums/z298/Bl4ckW0lfi3/10ohm_resistor_zpsaa1eeb3a.jpg)

Testing same 100uF cap and 10ohm resistor in series doesn’t change the output frequency, it stays same as when you test the cap, even the waveform stays same, oddly LCR tester measures the cap value little higher:
(http://i193.photobucket.com/albums/z298/Bl4ckW0lfi3/100uF_and_10ohm_zps16cc5520.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on March 16, 2013, 06:56:35 am
Hey Spawn, thanks a lot !  :-+

Trying capture anything with a 4k storage was a real task, I could only capture in magnified sec/div at 5nS but the thing is this tester puts out different waveforms till it can measure and I could only capture the last one and the frequency of these are really odd. I think a DSO with proper storage could see a lot more. Maybe someone with a decent scope can help us?
Yeah, that signal kinda weird and has unique pattern at the 1st test on open connection. And it looks like a square wave with quite slow rise/fall time to me ? Is it the scope speed limitation ?

Anyone with high speed scope, please share the test signal please.


Its cool to see it could measure your probe's input resistance at 1Meg ohm.

Looking at the test signal, at vertical about 2V, your scope shows the signal's Vpp is about 8.x Volt, and wonder if this high voltage could do harm on low voltage capacitor like 6.3 Volt or even those 2.5 or 1.8 volt expensive polymer caps ?  ???
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 16, 2013, 07:39:55 am
Anyone with high speed scope, please share the test signal please.

There's no need for high end gear ;-) Just check out the source code! Large caps are charged with pulses until a specific voltage is reached. Multiply the number of pulses with the pulse width and you'll have the time. Then use the famous equation for charging capacitors to get the capacitance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on March 16, 2013, 07:46:58 am
Anyone with high speed scope, please share the test signal please.

There's no need for high end gear ;-) Just check out the source code! Large caps are charged with pulses until a specific voltage is reached. Multiply the number of pulses with the pulse width and you'll have the time. Then use the famous equation for charging capacitors to get the capacitance.
OIC, thanks Markus for the the explanation on the cap measurement method ! Its just I'm lazy to go through the source code !  ;D

As my question, so this thing can not be used on low voltage cap ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on March 16, 2013, 11:00:44 am
OIC, thanks Markus for the the explanation on the cap measurement method ! Its just I'm lazy to go through the source code !  ;D

As my question, so this thing can not be used on low voltage cap ?

You don't even have to decypher the source code. It's covered in the documentation that was posted on page 1 of this thread:

5.3.2 Measurement of big Capacitors
One side of the capacitor is connected to GND. The other side of the capacitor is connected with
the 680  resistor to VCC for a period of 10ms. Afterwards this probe pin is switched to Input (High
Impedance). After this 10 ms current pulse the voltage of the capacitor is measured without any
current. If the voltage has not reached a minimal value of 300mV, the load pulse is repeated up to
499 times. If after 127 pulses a minimum voltage of 75mV is not reached (about 2s), further load
is stopped, because never the 300mV can be reached with the remaining load pulses. Figure 5.21
shows the three phases of measuring the capacity value of a capacitor. The value of the capacity is
then computed with the count of load pulses and the reached load voltage from a table. The table
contains the factors to get the capacity in nF units from load time and the reached voltage with a
spacing of 25mV. Interim value of voltage will be interpolated.

Now I realize that VCC in this case is 5v, which is technically above the 1.8v you are concerned about. For all of 10ms. I don't really know much about such low voltage caps or if they are robust enough to take a brief pulse, but certainly the 6.3 volt caps are in no danger.

Personally, the highest voltage I saw on the scope during my own experimenting was about 3.5v, but I don't remember how big the cap was. It might well go higher with a low-value cap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on March 16, 2013, 11:55:35 am
Unless I'm reading Spawn's scope shots wrongly and CMIIW, isn't that his test voltages are quite high ?  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: Spawn on March 16, 2013, 01:42:10 pm
Yes indeed my scope reads around 8volts, you can see the volt/div switch on channel 1 at 2volts, probe is 10x Tek P6109. About the speed BravoV, I could go one lower in magnified situation to 5ns that’s the fastest it gets but the signal got so vague I couldn’t see where to put the cursors to measure something.

Other important thing I forgot to mention is, I had a fresh battery every time when you push the button it tests the battery, at the start it was 9.5volts after around 20 tests while I was trying to find good setting on my scope to get a waveform it dropped to 8.9volts. I am not sure how many tests you can do with caps, I could give a go on a fresh battery and average value cap to see that but then it will be waste of my 9volt battery  ^-^
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 16, 2013, 10:58:49 pm
OIC, thanks Markus for the the explanation on the cap measurement method ! Its just I'm lazy to go through the source code !  ;D

You're welcome! Who isn't lazy? :-)

Quote
As my question, so this thing can not be used on low voltage cap ?

The charging of any cap stops at about 1300mV maximum. And for large caps (>50µF) the current is limited by a 680 Ohms resistor (@5V), i.e. about 7mA. For small caps it's a 470k resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: space_bastard on March 17, 2013, 12:28:07 am
Awesome build! Just came across this diy ESR meter on Hackaday:

http://hackaday.com/2013/03/16/testing-caps-with-a-diy-esr-meter/ (http://hackaday.com/2013/03/16/testing-caps-with-a-diy-esr-meter/)

I have been looking for a cheap way to test caps, I may have to look into a diy solution!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on March 17, 2013, 01:15:31 am
Awesome build! Just came across this diy ESR meter on Hackaday:

http://hackaday.com/2013/03/16/testing-caps-with-a-diy-esr-meter/ (http://hackaday.com/2013/03/16/testing-caps-with-a-diy-esr-meter/)

I have been looking for a cheap way to test caps, I may have to look into a diy solution!

I looked at the design today also.  And decided to build one. So tore down a couple of pc power supplies to rob the step down transformers out of. But ended up making 2 bench power supplies out of them.  :-//

Anyway ordered the one posted here in this thread today.
Title: Re: $20 LCR ESR Transistor checker project
Post by: notsob on March 17, 2013, 01:30:37 am
And here's an interesting one, by Fr Tom McGahee on his cap meter design, pcb pdf's and PIC code available (of course you'll have to modify the code for a later version PIC)
Title: Re: $20 LCR ESR Transistor checker project
Post by: space_bastard on March 17, 2013, 05:53:09 am
Awesome build! Just came across this diy ESR meter on Hackaday:

http://hackaday.com/2013/03/16/testing-caps-with-a-diy-esr-meter/ (http://hackaday.com/2013/03/16/testing-caps-with-a-diy-esr-meter/)

I have been looking for a cheap way to test caps, I may have to look into a diy solution!

I looked at the design today also.  And decided to build one. So tore down a couple of pc power supplies to rob the step down transformers out of. But ended up making 2 bench power supplies out of them.  :-//

Anyway ordered the one posted here in this thread today.

You can never have too many power supplies!  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 25, 2013, 05:13:02 pm
My new firmware 1.06m is released. New features are an improved UI, use of the MCU sleep modes to reduce power consumption (as in 1.06k) and a PWM generator. You can choose between several pre-defined frequencies in a menu and increase or decrease the duty ratio in steps of 5%. But beware :-) No ESR or L measurements are supported (if you need those go for 1.06k).

You'll find all firmwares and docs at http://www.mikrocontroller.net/svnbrowser/transistortester/. (http://www.mikrocontroller.net/svnbrowser/transistortester/.) The m-version is located under Software/Markus.

Have fun!
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on March 26, 2013, 05:07:56 am
Thanks Markus.

Any reason for removing ESR and L? Is this an issue of code space in the Atmega168 ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on March 26, 2013, 04:52:13 pm
Markus,
Do you still offer compile code?
Thank you very much :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 26, 2013, 10:13:32 pm
Any reason for removing ESR and L? Is this an issue of code space in the Atmega168 ?

Never added those to my firmware fork :-) Some time ago when Karl-Heinz was adding the inductance measurement (k version) I also played with that but dropped it because the measurement range is very limited. Later Karl-Heinz expanded the range by running the ATmega out-of-spec for a short period of time (so far no ATmega died from that :-). The ESR measurement was similar and don't forget the odd test frequency. I don't think that there's much gain by ESR and L measurements with quite limited ranges. A dedicated LCR meter is much better for that. And yes, the ATmega168 is nearly maxed out.

PS: Karl-Heinz is improving the ESR measurement at the moment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 26, 2013, 10:26:06 pm
Do you still offer compile code?

It's open source software and hardware. Nothing to hide :-) Karl-Heinz always creates a few precompiled firmwares for some common hardware
setups (for the lazy :-).

Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on March 26, 2013, 11:31:40 pm
I got my tester in yesterday, but was too sick to play with it. I did get a chance to use it tonight. Very nice. I like it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on March 28, 2013, 09:48:05 pm
Actually Lazy is one of my nicknames :)
I originally purchased the semiconductor tester from www.warf.com (http://www.warf.com) as it comes with a nice case. it worked well but it had a couple of bugs on the firmware. I purchased a couple of Atmega8 and and the USB ASP to be able to program the chips, download the pre-compiled software and programmed the chips with the AVR extreme burner. It worked fine but then I found out that Karl was working on an improved version of your original design so I purchased the other version of the component tester version 2.2 on exxy.com and also a couple of Atmega328 to play with. I haven't compiled for a long time. I come from a strictly assembly language background (z80, 8088, 6800, 8051, 68HC11) so here I am again downloading the WinAvr suite and trying to figure out how to use it. I just wanted to try your newest version of the firmware on my original design hardware. Yeah, It might take me a couple of nights to figure out how to compile the code ......... call me lazy :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 28, 2013, 11:14:50 pm
software and programmed the chips with the AVR extreme burner. It worked fine but then I found out that Karl was working on an improved version of your original design so I purchased the other version of the component tester version 2.2 on exxy.com and also a couple of Atmega328 to play with.

The original design was done by another Markus. I joined Karl-Heinz last year.

Quote
I haven't compiled for a long time. I come from a strictly assembly language background (z80, 8088, 6800, 8051, 68HC11) so here I am again downloading the WinAvr suite and trying to figure out how to use it.

Still got my 68HC11 developer board ;-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on March 31, 2013, 02:08:04 am
Blah, was going to use the new tester today for the first time in a real world test. Bloody thing failed to come on.  :palm: I only tested new caps out of the parts bin since I had it.  So today someone brought over a board with possible caps bad.  I said hey, let me show you thing neat gadget I just got. And it would not turn on   :-BROKE Boy did I feel stupid. Anyway I will give anything a second try. So I ordered another one.  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on March 31, 2013, 02:40:44 am
And it would not turn on   :-BROKE Boy did I feel stupid. Anyway I will give anything a second try. So I ordered another one.  |O
You didn't unplug the display, and then plug it back - but out by one pin? Easy to do.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on March 31, 2013, 02:48:31 am
And it would not turn on   :-BROKE Boy did I feel stupid. Anyway I will give anything a second try. So I ordered another one.  |O
You didn't unplug the display, and then plug it back - but out by one pin? Easy to do.

Nope. Wish it had been that easy lol.  Thought maybe a bad battery. But it was good. tried another to be sure. Got voltage on the board but no display. The red LED will not come on either. Probably controller failure. When I get the cance this week I will do a bit more troubleshooting. The Ebay seller offered to replace it. Told him no worries I will just order another, so I did. Now I have one to tear down  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: kubi48 on April 20, 2013, 07:00:00 am
Hello,
I would like to tell you, that a new version of my TransistorTester software is ready for download from the mikrocontroller.net site.
The main advantage of the new version is a improved ESR measurement, which can now determine ESR for capacitors with more than 0.18 uF. The new approach use shorter current pulses to measure the ESR.
Additionally this method can be used to measure resistors too. This gives a resolution of 0.01 Ohm for resistors with less than 10 Ohm and the calibration use this function to measure the zero resistance. So no more the extra calibration of ESR zero with big capacitors is required. In the majority of cases the new ESR measurement gives lower results because the shorter pulses make the result more like a 10 kHz measurement.
Additionally a new parameter is output for capacitors with more than 5000 pF and low quality factor. This parameter is the voltage loss (Vloss) immediately after a load pulse. Some older paper capacitors make problems to get the right capacity. The error can be more than 100%. Also other instruments have problems to measure the right capacity for that capacitors. For this type of capacitor a voltage loss of more than 10% was measured, so the TransistorTester gives you a warning hint with the Vloss now.

Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on April 20, 2013, 08:22:40 am
That's at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/) I guess. V107 is only 21 hours old.

Here is a Google Translate of the changelog:
Quote
Makefile option NO_NANO Specific activity complements.
Extended function GetVloss for capacitors with more than 5nF, previously 50nF.
The self-test Let's remove the short-circuit test at 4 is monitored, AllProbesShorted by Markus R.
The GetESR function is used during calibration to determine the zero resistance (pin-dependent).
GetESR function is also used for resistance values ??below 10 ohms.
Function GetESR replaced by new assembler function.
New feature GetVloss to measure the voltage drop after a charge pulse at small 45uF capacitors.
The GetESR function converted to assembler to make the time sequence regardless of the compiler optimization.
Assignment of Flash and EEPROM memory optimized.
BAT_POOR level changed in the Makefile to mV indication, indication of just 1.3V +0.1 V warning.
ESR measurement for capacitors from 0.45uF supplemented with 500kHz ADC clock.
The resolution of the inductance is set to 0.1mH Resistance 680 ohms.
The Pinreihenfolge with individual diodes is issued in accordance ATmega168/328 EBC_STYLE.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on April 20, 2013, 10:16:53 am
Well this sounds intriguing!

I've never played with these AT projects. A quick google tells me there are a variety of ways to upload programming to these chips.  The Chinese board seems to have a 10 pin unpopulated header that might be the interface for the soldered processor. Can anyone confirm this?

Supplementary question: does this look like a suitable programmer: http://www.ebay.com/itm/USB-ISP-Programmer-for-ATMEL-AVR-51-ATMega-ATTiny-/200460739146 (http://www.ebay.com/itm/USB-ISP-Programmer-for-ATMEL-AVR-51-ATMega-ATTiny-/200460739146) ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: kubi48 on April 20, 2013, 10:59:33 am
The chinese board uses a 10 pin ISP header. The ISP interface is specified as 10 pin or 6 pin header.
I don't know anything about the quality of the ISP programmer with USB interface in your link.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 20, 2013, 03:43:07 pm
I've never played with these AT projects. A quick google tells me there are a variety of ways to upload programming to these chips.  The Chinese board seems to have a 10 pin unpopulated header that might be the interface for the soldered processor. Can anyone confirm this?

The 6 or 10 pin header is the ISP interface supported by ATtiny and ATmega MCUs. The drawback of the ISP interface is that it can't be used if the fuses are messed up badly. In that case you'll need a so called HV parallel programmer. AFAIK the Dragon board supports both methods.

Quote
Supplementary question: does this look like a suitable programmer: http://www.ebay.com/itm/USB-ISP-Programmer-for-ATMEL-AVR-51-ATMega-ATTiny-/200460739146 (http://www.ebay.com/itm/USB-ISP-Programmer-for-ATMEL-AVR-51-ATMega-ATTiny-/200460739146) ?

Make sure the progammer is supported by avrdude or is compatible with STK-500.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on April 20, 2013, 09:13:13 pm
Well, according to Mr. Karl-Heinz Kübbeler (in his excellent documentation referenced on page 1 of this thread) when he tested one of the Chinese versions:

Quote
The lock fuses of the ATmega were set, so no readout was possible. But I could install the software version 1.05k without any problems.

He doesn't specify exactly what method he used to install the software, but I will guess he used the ISP header interface since he mentions it earlier in the section, and I think he would have said something if it didn't work.

The unit I found on fleabay indicates it is is "based on Thomas Fischl's USBasp design". I found a tutorial on using USBasp with Avrdude, so my guess is that it is compatible. However, that particular unit comes with Chinese language software/manual only, so I think I'll keep looking for something with English support. I will have enough trouble understanding the English...  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: hunter on April 22, 2013, 03:40:42 am
I would like to know if it is possible to reflash/update the firmware on the chip with Arduino board. They seem to use ATmega chip as well. Is it same procedure as with normal Arduino code ?

The old one uses removable chip , while the new one has a tiny chip soldered. So I am sure the new one is not update able.  ???

Old one: /ebay
(http://i.ebayimg.com/t/NEWEST-AVR-Transistor-Tester-meter-NPN-PNP-MOSFET-diode-triac-resistor-capacitor-/00/s/NjAwWDgwMA==/z/kyMAAMXQTghRN2mj/$T2eC16dHJHIE9nysfBj6BRN2mjs4,!~~60_3.JPG)

New one: /ebay
(http://hk2.image.pushauction.com/ViewPicture.aspx?Key=46ec5f0d-de2b-4456-ac5f-730737bb6a3b_d572ea3c-8092-46dc-9074-02c580022aa5)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ecat on April 22, 2013, 09:41:40 am
@hunter

See the 10 holes (5x2) on the left side of the new board?
High probability these are for a programming header :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on April 22, 2013, 09:46:14 am
That's the one I have. I believe the 10 unpopulated holes on the left side are the ISP programming header. I'm going to try upgrading to V1.07 with this Usbasp programmer: http://www.ebay.com/itm/300695243866. (http://www.ebay.com/itm/300695243866.) It specifically mentions it is compatible with the avrdude software as recommended by madires.

I'll let you know if it works once the programmer arrives and I have time to figure this out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 22, 2013, 11:42:52 am
See the 10 holes (5x2) on the left side of the new board?
High probability these are for a programming header :)

Good guess! :-)  Please see http://www.batsocks.co.uk/readme/isp_headers.htm (http://www.batsocks.co.uk/readme/isp_headers.htm) for the 6 and 10pin ISP headers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kubi48 on April 22, 2013, 02:18:10 pm
Here is my early version of the new Tester with some modifications.
The 10-pin ISP header is soldered, but one side of the frame must be cut out
to match the room left for the header.
The original potentiometer has been replaced to a exemplar with higher resistance
(10k) to save power.
Two blocking capacitors of 100nF each are additionally mounted near the ATmega.
The D1 zener diode is replaced by a precision voltage reference like LM4040AIZ2.5 .
If you don't have a precision voltage reference, you should remove the zener diode at least.
I had also replaced the original 78L05 regulator by my preferred MCP1702-5002 regulator,
because this regulator can also save quiescent current.
Regards, Karl-Heinz
Title: Re: $20 LCR ESR Transistor checker project
Post by: moemoe on July 15, 2013, 06:21:48 am
Karl-Heinz (the current main developer of the software) started to implement an enhanced software for the 328 in the current trunk http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/)

This version uses the additional space to measures the current amplification in emitter and collector configuration (don't know the correct english term here, perhaps I should visit english for engineers next semester).

And, as there are many problems in the thread at http://www.mikrocontroller.net/topic/248078 (http://www.mikrocontroller.net/topic/248078) due to sleep mode and wrong oscillator, just a little hint:
When using sleep modes and the internal RC oscillator, you have to set 'RESTART_DELAY_TICS=6' because the wake up is faster and therefore timing is calculated wrong so that you will get wrong capacitor values.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 17, 2013, 04:38:02 pm
1.09m is released:
- fixed a pin assignment bug for MOSFETs
- leakage current is considered for hFE now
- detection of IGBTs (if the tester is able to exceed the gate threshold voltage)

http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on July 17, 2013, 05:14:41 pm
Nice!!!  :-+ :-+ :-+

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on July 18, 2013, 03:18:31 pm
Damn it, Markus and Karl-Heinz!
You made me succumb to the temptation of ignoring your project and, finally, to build that relentless spare-time killing device*! :)

Kidding aside, please let me contribute a little something to this fine project, and feel free to use it at will. This will be a surprisingly accurate version of the Sleep_5ms/MilliSleep time delay functions you already make use of.

The following version of the sleep-time delay breaks down the total requested sleep-time to three partial and very accurate TC2 wait times of 16.00 ms, 3.00 ms and 1.00 ms. Additionally, it utilises the Extended Standby Sleep Mode instead of the Idle Sleep Mode (that introduces timing errors for reasons currently unknown to me). Trying to keep the function spartan, the resulting timing error is a couple (or three or four in the worst case!) microseconds only, regardless of the total requested time delay, which is in the range of 1.00 ms to 65535.00 ms!

There are two problems, though:
The obvious one is that this function has to be ported to C, in order to be utilised in the current project --which is a trivial task.
The second one is that, in its current form, the function does only support the crystal oscillator option at 8.0 MHz (that I use in my implementation), since the RC oscillator needs very different start-up times and makes the redefinition of the partial delays an absolute requirement. Of course, the function can be rewritten to support the 16.0 MHz crystal oscillator or the 8 MHz RC oscillator option.

This is the assembly code:

Code: [Select]
;-------------------------------------------------------------------------------
; Registers definitions
;-------------------------------------------------------------------------------
;.def = r0 ; Temp / Product of the MULx instructions: [r1:r0]
;.def = r1 ;
.def C0 = r2 ; Temp / Math registers: [C7:C0]
.def C1 = r3 ;
.def C2 = r4 ;
.def C3 = r5 ;
.def C4 = r6 ;
.def C5 = r7 ;
.def C6 = r8 ;
.def C7 = r9 ;
.def D0 = r10 ; Temp / Math registers: [D3:D0]
.def D1 = r11 ;
.def D2 = r12 ;
.def D3 = r13 ;
;.def = r14 ; Ct. = 0xFF
.def Zero = r15 ; Ct. = 0x00
.def A0 = r16 ; Temp / Math registers: [A3:A0]
.def A1 = r17 ;
.def A2 = r18 ;
.def A3 = r19 ;
.def B0 = r20 ; Temp / Math registers: [B3:B0]
.def B1 = r21 ;
.def B2 = r22 ;
.def B3 = r23 ;
.def T0 = r24 ; 16-bit temp: [T1:T0]
.def T1 = r25 ;
;.def XL = r26 ; X pointer: [XH:XL]
;.def XH = r27 ;
;.def YL = r28 ; Y pointer: [YH:YL]
;.def YH = r29 ;
;.def ZL = r30 ; Z pointer: [ZH:ZL]
;.def ZH = r31 ;


;-------------------------------------------------------------------------------
Sleep_1ms_Init: ; <Sleep_1ms> function initialisation
;-------------------------------------------------------------------------------
;     Initialisation of the <Sleep_1ms> function
;
; Syntax:
; call Sleep_1ms_Init ; Initialise the <Sleep_1ms> function
;
; <Sleep_1ms_Init> Parameters:
;   None!
; <Sleep_1ms_Init> Returns:
;   None!
;
; Registers used:
;   Zero;  Non-destructive use of <Zero> that can be any CPU register loaded with the constant value of 0x00
;   A0;    Non-destructive use of <A0> that can be any of the CPU high-registers (r16..r31)
;
push A0 ; Preserve the <A0> temp
; Stop and disable TC2 and TC2 ISRs
sts TCCR2B,Zero ; [FOC2A,FOC2B,-,-,WGM22,CS22,CS21,CS20]
sts TIMSK2,Zero ; [-,-,-,-,-,OCIE2B,OCIE2A,TOIE2]
sts TCNT2,Zero ; Reset TC2
; Set TC2 mode to CTC (WGM22:20 = 0b010)
ldi A0,1<<WGM21 ; Mode 2 (CTC): WGM22:20 = 0b010
sts TCCR2A,A0 ; [COM2A1,COM2A0,COM2B1,COM2B0,-,-,WGM21,WGM20]
sts ASSR,Zero ; [-,EXCLK,AS2,TCN2UB,OCR2AUB,OCR2BUB,TCR2AUB,TCR2BUB]
; Avoid any TIM2_COMPA ISR firing caused by possible low values loaded to OCR2A
ldi A0,-1 ;
out TIFR2,A0 ; [-,-,-,-,-,OCF2B,OCF2A,TOV2]
sts OCR2A,A0
; Done!
; cbi PORTC,3 ; ########  D E B U G G I N G  ########
; cbi PORTC,4 ; ########  D E B U G G I N G  ########
; sbi DDRC,3 ; ########  D E B U G G I N G  ########
; sbi DDRC,4 ; ########  D E B U G G I N G  ########
pop A0 ; Restore the <A0> temp
ret


;-------------------------------------------------------------------------------
Sleep_1ms: ; Sleep for <T1:T0> * 1 ms time
;-------------------------------------------------------------------------------
;     Set the CPU to sleep for <T1:T0> times 1ms
;
; Syntax:
; ldi T0,Byte1(Delay) ; <Delay> is the requested sleep-time delay
; ldi T1,Byte2(Delay) ;  in 1 ms steps. Range: Delay = 1..65535
; call Sleep_1ms ; Sleep for <T1:T0> * 1 ms time
;
; <Sleep_1ms> Parameters:
;   T1:T0 = 1..65535, in 1 ms steps
; <Sleep_1ms> Returns:
;   None!
;
; Registers used:
;   Zero;  Non-destructive use of <Zero> that can be any CPU register loaded with the constant value of 0x00
;   A0;    Non-destructive use of <A0> temp that can be any of the CPU high-registers (r16..r31)
;   T1:T0; Destructive use of <T1:T0> that should be any of the 16-bit addressing capable register pairs (r25:r24, X, Y or Z)
;
.equ Restart_Delay_Tics = 16384                            ; CPU restart delay, in Clk cycles
.equ Restart_Delay = Restart_Delay_Tics*1000000/F_CPU ; 2048 ms for 8 MHz clock
.equ T2_Period_004 =    32 * 1000000/F_CPU            ;    4 µs for 8 MHz clock
.equ T2_Period_128 =  1024 * 1000000/F_CPU            ;  128 µs for 8 MHz clock
; Preamble
; sbi PORTC,3 ; ########  D E B U G G I N G  ########
push A0 ; Preserve the <A0> temp
ldi A0,1<<OCIE2A ; Enable the TC2 Output Compare Match A interrupt
out TIFR2,A0 ; [-,-,-,-,-,OCF2B,OCF2A,TOV2]
sts TIMSK2,A0 ; [-,-,-,-,-,OCIE2B,OCIE2A,TOIE2]
sei ; Now, we can safely enable global interrupts

; <T1:T0>: Delay register, in 1.0 ms units step
 _Slp1ms_Dly: wdr ; Prevent a WD timeout event
; sbi PORTC,4 ; ########  D E B U G G I N G  ########
; Fast Clk (4 µs / 250 kHz)
ldi A0,1<<CS21|1<<CS20 ; T2_Period = Clk/32 = 4 µs
sts TCCR2B,A0 ; [FOC2A,FOC2B,-,-,WGM22,CS22,CS21,CS20]
ldi A0,1<<PSRASY ; TC2 prescaller reset
out GTCCR,A0 ; [TSM,-,-,-,-,-,PSRASY,PSRSYNC]
sts TCNT2,Zero ; Reset TC2
; Delay module (1/3/16 ms)
cpi T0,Byte1(3)
cpc T1,Zero
brlo _Slp1ms_01m ; Delay < 3 ms
cpi T0,Byte1(16)
cpc T1,Zero
brlo _Slp1ms_03m ; Delay < 16 ms
; Slow Clk (128 µs / 7812.5 Hz)
ldi A0,1<<CS22|1<<CS21|1<<CS20 ; T2_Period = Clk/1024 = 128 µs
sts TCCR2B,A0 ; [FOC2A,FOC2B,-,-,WGM22,CS22,CS21,CS20]
ldi A0,1<<PSRASY ; TC2 prescaller reset
out GTCCR,A0 ; [TSM,-,-,-,-,-,PSRASY,PSRSYNC]
sts TCNT2,Zero ; Reset TC2

; 16.00 ms to sleep: Use the Power Save Sleep Mode
;  OCR2A = ((16000µs-2048µs)/128µs)-1 = (13952µs/128µµs)-1 = 109-1
 _Slp1ms_16m: ldi A0,((16000-Restart_Delay)/T2_Period_128)-1
sts OCR2A,A0
; Set the Sleep Mode to Power Save (SM2:0 = 0b011)
ldi A0,1<<SM1|1<<SM0|1<<SE
out SMCR,A0 ; [-,-,-,-,SM2,SM1,SM0,SE]
sleep
; Update the Delay register
sbiw T0,16 ; Delay register timed-out?
; cbi PORTC,4 ; ########  D E B U G G I N G  ########
brne _Slp1ms_Dly ;  Not yet. Else:
rjmp __Slp1ms_X

; 3.00 ms to sleep: Use the Power Save Sleep Mode
;  OCR2A = ((3000µs-2048µs)/4µs)-1 = (952µs/4µs)-1 = 238-1
 _Slp1ms_03m: ldi A0,((3000-Restart_Delay)/T2_Period_004)-1
sts OCR2A,A0
; Set the Sleep Mode to Power Save (SM2:0 = 0b011)
ldi A0,1<<SM1|1<<SM0|1<<SE
out SMCR,A0 ; [-,-,-,-,SM2,SM1,SM0,SE]
sleep
; Update the Delay register
sbiw T0,3 ; Delay register timed-out?
; cbi PORTC,4 ; ########  D E B U G G I N G  ########
brne _Slp1ms_Dly ;  Not yet. Else:
rjmp __Slp1ms_X

; 1.00 ms to sleep: Use the Extended Standby Sleep Mode (no Restart Delay)
;  OCR2A = (1000µs/4µs)-1 = 250-1
 _Slp1ms_01m: ldi A0,(1000/T2_Period_004)-1
sts OCR2A,A0
; Set the Sleep Mode to Extended Standby (SM2:0 = 0b111)
ldi A0,1<<SM2|1<<SM1|1<<SM0|1<<SE
out SMCR,A0 ; [-,-,-,-,SM2,SM1,SM0,SE]
sleep
; Update the Delay register
sbiw T0,1 ; Delay register timed-out?
; cbi PORTC,4 ; ########  D E B U G G I N G  ########
brne _Slp1ms_Dly ;  Not yet. Else:

; Done! Stop TCNT2 and disable OCIE2A and the Sleep Modes
 __Slp1ms_X: sts TCCR2B,Zero ; [FOC2A,FOC2B,-,-,WGM22,CS22,CS21,CS20]
sts TIMSK2,Zero ; [-,-,-,-,-,OCIE2B,OCIE2A,TOIE2]
out SMCR,Zero ; [-,-,-,-,SM2,SM1,SM0,SE]
pop A0 ; Restore the <A0> temp
; cbi PORTC,3 ; ########  D E B U G G I N G  ########
ret

-George


EDIT:
Corrections of the premature and incomplete assembler code that was mistakenly posted.


(*) Here are a few ideas that might be of some use for the project.
This is my hardware version of a single layer PCB, an easy one to be built at home, with the following modifications:
- Additional PCB space to host a 9V battery, for an autonomous and completely floating testing device.
- The use of the more accurate and flexible LP2950-5.0 LDO/reference, which eliminates the need for an external voltage reference diode.
- The addition of R2 in series to the push-button, in order for the FW to be able to use the LED indicator independently of the  push-button state (because without R2, when the push-button is ON the Q3 B-E junction limits the LED anode voltage to ~0.7V only).
- The omission of the LCD backlight current limiting resistor and the LCD Vee bias trimmer, since both those LCD module requirements are handled internally by elements (resistors) added directly to the LCD module PCB.
- Finally, the addition of a BootLoader header port (J3) for faster and less hassle FW updates, for those who really enjoy messing with the firmware!

Here are the schematics and the PCB top and bottom layout views of my Component Tester implementation:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 18, 2013, 05:00:55 pm
You made me succumb to the temptation of ignoring your project and, finally, to build that relentless spare-time killing device*! :)

It's part of our secret world domination plan :-)

Quote
Kidding aside, please let me contribute a little something to this fine project, and feel free to use it at will. This will be a surprisingly accurate version of the Sleep_5ms/MilliSleep time delay functions you already make use of.

Thanks! The sleep function doesn't has to be very accurate at the moment, it's just used to wait for uncritical stuff and saving power. But in case we need a more accurate version I got some nice code now :-)

Quote
(*) Here are a few ideas that might be of some use for the project.
This is my hardware version of a single layer PCB, an easy one to be built at home, with the following modifications:
- Additional PCB space to host a 9V battery, for an autonomous and completely floating testing device.
- The use of the more accurate and flexible LP2950-5.0 LDO/reference, which eliminates the need for an external voltage reference diode.
- The addition of R2 in series to the push-button, in order for the FW to be able to use the LED indicator independently of the  push-button state (because without R2, when the push-button is ON the Q3 B-E junction limits the LED anode voltage to ~0.7V only).
- The omission of the LCD backlight current limiting resistor and the LCD Vee bias trimmer, since both those LCD module requirements are handled internally by elements (resistors) added directly to the LCD module PCB.
- Finally, the addition of a BootLoader header port (J3) for faster and less hassle FW updates, for those who really enjoy messing with the firmware!

I wouldn't choose the 7805/78L05 either, the MCP1702 works also really great (0,4%). We're very careful with changes to keep everything compatible. But you could create a zip file with the layout and some documentation for the SVN if you like.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on July 18, 2013, 05:16:24 pm
It's part of our secret world domination plan :-)

Oh, please my dear friend, do not force me to reveal my own agenda by changing my avatar to this, below... :-)


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: vehf277 on August 18, 2013, 07:31:21 pm
Hello,
Can this tester be used as in-circuit ESR meter?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 19, 2013, 11:31:58 am
Can this tester be used as in-circuit ESR meter?

No, because the voltage used is higher than 0.7V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on August 19, 2013, 12:00:25 pm
Few months ago I was working  on a monitor and checking some caps. I replace some bad caps and powered it up and then decided I needed to check the main cap on the power supply. Remove cap connected the tester and nothing, no power on.  I realized I did not short the cap before testing.

Pretty sure it took the controller out. So just bought another.
Question is this, is it worth taking the time to replace the chip and reprogram it?  I have no problem changing the chip. But the programming may be an issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 19, 2013, 12:23:06 pm
Few months ago I was working  on a monitor and checking some caps. I replace some bad caps and powered it up and then decided I needed to check the main cap on the power supply. Remove cap connected the tester and nothing, no power on.  I realized I did not short the cap before testing.

There's an official mod for discharging caps with higher voltages (based on a relay). IIRC it's in Karl-Heinz' documentation.

Quote
Pretty sure it took the controller out. So just bought another.
Question is this, is it worth taking the time to replace the chip and reprogram it?  I have no problem changing the chip. But the programming may be an issue.

Yes, any ISP capable programmer will do the job. If the tester you bought matches the reference design you don't even need to compile a matching firmware. Please see http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) for precompiled firmwares and the source code.

BTW: I'd recommend an ATmega328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on August 19, 2013, 01:14:16 pm
Thanks,
i'll give it a go.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vehf277 on August 19, 2013, 04:27:36 pm
Can this tester be used as in-circuit ESR meter?

No, because the voltage used is higher than 0.7V.
Thank you very much.
It would be great if there is is a way to modify the tester as it can be in-circuit ESR meter cos it is abnormally big price for specialized ESR testers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on August 19, 2013, 05:57:24 pm
You can, provided you are testing a circuit that won't be damaged by voltages over 0.7v
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on August 19, 2013, 06:24:31 pm
It is not only damage. Voltage bigger than 0.7 can turn things on and the reading wont be reliable.

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 19, 2013, 07:21:17 pm
Thank you very much.
It would be great if there is is a way to modify the tester as it can be in-circuit ESR meter cos it is abnormally big price for specialized ESR testers.

You're welcome! An in-circuit ESR meter would require a special design for low voltages and that would break the hardware-software compatibility we have. But there are a some circuits for dedicated ESR meters, please see https://www.eevblog.com/forum/beginners/esr-meter-circuit/ (https://www.eevblog.com/forum/beginners/esr-meter-circuit/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: vehf277 on August 19, 2013, 09:41:44 pm

You're welcome! An in-circuit ESR meter would require a special design for low voltages and that would break the hardware-software compatibility we have. But there are a some circuits for dedicated ESR meters, please see https://www.eevblog.com/forum/beginners/esr-meter-circuit/ (https://www.eevblog.com/forum/beginners/esr-meter-circuit/).
I know that URL. I spent a lot of time trying to find a good device for small money and I thought I've done but to my surprise I missed. Thank you very much anyway :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stonent on August 20, 2013, 01:39:34 am
To prevent damage I wonder if a relay could be installed that shorts the test pins or maybe a button that you must hold down during the test. When you let go, it shorts the pins.

The relay could be normally closed but then goes open when a test is running, then closes again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 20, 2013, 11:35:45 am
To prevent damage I wonder if a relay could be installed that shorts the test pins or maybe a button that you must hold down during the test. When you let go, it shorts the pins.

The relay could be normally closed but then goes open when a test is running, then closes again.

You're not the first one with that idea :-) Currently there are two moifications supported by Karl-Heinz' firmware. The first one is a relay based discharger for caps (voltage > 5V) and a zener test with a higher voltage (DC-DC converter based). Both are described in the documentation IIRC. And the third mod is a PWM driven backlight control (see my schematics in the SVN).
Title: Re: $20 LCR ESR Transistor checker project
Post by: noidea on September 18, 2013, 06:22:56 am
Hi All
I had just started researching about how to create an electronic component tester using a microcontroller, and found the link to these devices as well as the original which suggest that somebody has already invented the wheel for me.
I was wondering if there was much difference between the various ones available on fleabay at the moment, can anyone make any recommendations as to which ones/sellers are the most up to date?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 18, 2013, 02:06:11 pm
I had just started researching about how to create an electronic component tester using a microcontroller, and found the link to these devices as well as the original which suggest that somebody has already invented the wheel for me.
I was wondering if there was much difference between the various ones available on fleabay at the moment, can anyone make any recommendations as to which ones/sellers are the most up to date?

Actually you can buy any clone since they are all based on the same circuit. But most need a little fix as described in the official documentation. AFAIK there is no clone at ebay that includes all hardware extensions. Please see http://www.mikrocontroller.net/svnbrowser/transistortester/ (http://www.mikrocontroller.net/svnbrowser/transistortester/) for the documentation (English and German) and firmware updates.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bench2013 on September 19, 2013, 02:42:02 am
Hi,

this thread looks awesome. I build one of these based on Markus F. (2009) very early design (ATMEGA8/48). It serves me well. I think time has move on, may be I should upgrade. Just wonder which controller does this Chinese clone comes with? Cheapo AMEGA8 or they put in more expensive 128/328? Always a dilemma, to build or to buy?

 :-+

Keep up the good work.

Ben
Title: Re: $20 LCR ESR Transistor checker project
Post by: toli on September 19, 2013, 05:42:26 am
I got mine a couple of days ago, ver 2.4. The fw is 1.05, and the IC is the ATMEGA168. They didn't even scrub that off:
https://dl.dropboxusercontent.com/u/37472979/IMG_0137.JPG

I just did the bare minimum by removing the zener (which measured 2.03V instead of 2.5V), and adding 2 decoupling caps on the ATMEGA, I didn't do any other mods, I'm less concerned with battery life as with my amount of use the battery with lose most of its charge by self-discharge anyway :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: noidea on September 19, 2013, 06:13:24 am
I got mine a couple of days ago, ver 2.4. The fw is 1.05, and the IC is the ATMEGA168. They didn't even scrub that off:

Thanks I have just spotted one that looks exactly the same as that based on the pcb markings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 19, 2013, 11:24:11 am
this thread looks awesome. I build one of these based on Markus F. (2009) very early design (ATMEGA8/48). It serves me well. I think time has move on, may be I should upgrade. Just wonder which controller does this Chinese clone comes with? Cheapo AMEGA8 or they put in more expensive 128/328? Always a dilemma, to build or to buy?

The clones we know about all got an ATmega168 but the 16k flash memory isn't enough to support all current firmware features. So I recommend to go for the ATmega328 (either replace the clone's 168 or build the tester yourself).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 19, 2013, 11:30:14 am
I got mine a couple of days ago, ver 2.4. The fw is 1.05, and the IC is the ATMEGA168. They didn't even scrub that off:
https://dl.dropboxusercontent.com/u/37472979/IMG_0137.JPG

Yep, that's one of the common clones. But the firmware is a tad old by now. Karl-Heinz' current version is 1.08k and mine is 1.09m (no ESR, no hardware extensions, but a PWM tool).
Title: Re: $20 LCR ESR Transistor checker project
Post by: jav on September 19, 2013, 12:43:03 pm
I got mine a couple of days ago, ver 2.4. The fw is 1.05, and the IC is the ATMEGA168. They didn't even scrub that off:
https://dl.dropboxusercontent.com/u/37472979/IMG_0137.JPG

Yep, that's one of the common clones. But the firmware is a tad old by now. Karl-Heinz' current version is 1.08k and mine is 1.09m (no ESR, no hardware extensions, but a PWM tool).
That's the one I've also bought, but I made some changes to it: Apart from the decoupling capacitors, I changed the voltage regulator and the CPU (ATmega328), added a voltage reference (instead of the zener) and a 8 MHz crystal. Then I changed to the 1.08k version and works great.

The software is awesome! Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: noidea on September 19, 2013, 12:50:00 pm
Yep, that's one of the common clones. But the firmware is a tad old by now. Karl-Heinz' current version is 1.08k and mine is 1.09m (no ESR, no hardware extensions, but a PWM tool).
[/quote]
I guess asking the seller to tell you what the version is the only way to find out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 19, 2013, 04:17:20 pm
I guess asking the seller to tell you what the version is the only way to find out.

It's not that important ;-) Add an ISP header and flash the current firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: krivx on September 19, 2013, 05:20:50 pm
Could someone provide a link to to the auction? I can only find the older DIP clone on ebay.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jav on September 19, 2013, 10:15:09 pm
Could someone provide a link to to the auction? I can only find the older DIP clone on ebay.
This is the one I bought. Even if in the pictures comes with the crystal installed, the ones I got don't have it.

www.ebay.com/itm/330917635775 (http://www.ebay.com/itm/330917635775)
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on September 19, 2013, 11:06:58 pm
Do a search on ebay for "transistor tester esr" and you'll find lots of sellers. I would chose one with back-lit LCD. There also many revisions of the board I think that there are revisions 2.1, 2.2, 2.3, and 2.4 on the SMD version. I don't know what the difference between the revisions are. I'm sure that it is discussed on the forum:
http://www.mikrocontroller.net/topic/248078. (http://www.mikrocontroller.net/topic/248078.)

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: noidea on September 20, 2013, 01:42:39 am
Could someone provide a link to to the auction? I can only find the older DIP clone on ebay.
I'm in Australia and are looking at this one
http://www.ebay.com.au/itm/290949358387 (http://www.ebay.com.au/itm/290949358387)

They also have a DIP version as well that's cheaper
http://www.ebay.com.au/itm/300937438443 (http://www.ebay.com.au/itm/300937438443)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 20, 2013, 01:52:33 am
Do a search on ebay for "transistor tester esr" and you'll find lots of sellers. I would chose one with back-lit LCD. There also many revisions of the board I think that there are revisions 2.1, 2.2, 2.3, and 2.4 on the SMD version. I don't know what the difference between the revisions are. I'm sure that it is discussed on the forum:
http://www.mikrocontroller.net/topic/248078. (http://www.mikrocontroller.net/topic/248078.)
Problem with the url it has a period at the end so returns a 404 error.

The issue with all of these on fleabay is that they do not say what version they are for the ones I quickly scanned over.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2013, 11:19:17 am
Problem with the url it has a period at the end so returns a 404 error.

Please try http://www.mikrocontroller.net/topic/248078 (http://www.mikrocontroller.net/topic/248078) :-)

That trailing dot is special (annoying) feature of this forum's software.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 20, 2013, 04:23:06 pm
Problem with the url it has a period at the end so returns a 404 error.

Please try http://www.mikrocontroller.net/topic/248078 (http://www.mikrocontroller.net/topic/248078) :-)

That trailing dot is special (annoying) feature of this forum's software.
Aye.

I did not read every page of this thread so please forgive me if this has been answered already but if I own an Arduino Mega can I use it to do what these do by simply connecting the appropriate pins and loading up the proper software?
Title: Re: $20 LCR ESR Transistor checker project
Post by: toli on September 20, 2013, 04:47:22 pm
I also got a little lost with the different revision of the fw. What was added/removed in each revision? Is the HW exactly the same in all revisions?

I guess its all somewhere in the documentation, but a quick look only gave me partial answers. Never mind, I'm very happy with it, and fact I ordered one from eBay and spent no time in building it myself is even better as I don't have the time right now :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2013, 07:33:04 pm
I did not read every page of this thread so please forgive me if this has been answered already but if I own an Arduino Mega can I use it to do what these do by simply connecting the appropriate pins and loading up the proper software?

You'll find a modified firmware for the Arduino at http://www.pighixxx.com/lavori/ardutester/ (http://www.pighixxx.com/lavori/ardutester/) (includes also a shield).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 20, 2013, 07:45:07 pm
I did not read every page of this thread so please forgive me if this has been answered already but if I own an Arduino Mega can I use it to do what these do by simply connecting the appropriate pins and loading up the proper software?

You'll find a modified firmware for the Arduino at http://www.pighixxx.com/lavori/ardutester/ (http://www.pighixxx.com/lavori/ardutester/) (includes also a shield).
So, best to buy one of those off of ebay then?  Seems less costly but lacks freedom too I think.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2013, 08:06:14 pm
I also got a little lost with the different revision of the fw. What was added/removed in each revision? Is the HW exactly the same in all revisions?

The firmware got additional features (can't remember them all :-) and tons of improvements. We keep everything compatible with the basic design, i.e. all hardware extensions are optional. If you got a very old hardware (Markus F.'s original design) you might need to apply some changes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: toli on September 20, 2013, 08:12:12 pm
The need to go and check is exactly why I don't do that, who's got the time?!  :(

Anyway, I'm happy with my unit. fw 1.05 might be a bit old, but it does what I need it to do. Resistors and capacitors are measured quite well with results no too far from my U1253A (actually very close to identical). Diodes Vf also about the same as I got at 6mA measurement in a test rig I once built (it had a temp chamber for temp-co measurement, and 6mA was used as this was the expected in circuit operation). I've measured some JFET's, BJT's, MOSFET's, everything seems to be good. Inductors are the only thing I can't confirm as I don't have an inductance meter (and the old time-constant measurement with the scope is too time consuming at the moment), but the values seem to be close to what's printed on the part so I guess its good as well.

I really only need it for ESR (to know if a cap is good or bad,  the exact value is of no interest to me), for inductance (again, precision isn't very important for my current needs), and for transistor matching - it can do all this so its well worth the price.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2013, 08:26:31 pm
So, best to buy one of those off of ebay then?  Seems less costly but lacks freedom too I think.

The Transistor Tester isn't a development platform, it's a tool designed for a specific purpose. The Arduino lacks the complete power management which the Transistor Tester got (optimized for battery usage).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2013, 08:39:06 pm
I really only need it for ESR (to know if a cap is good or bad,  the exact value is of no interest to me), for inductance (again, precision isn't very important for my current needs), and for transistor matching - it can do all this so its well worth the price.

1.07k got an improved ESR measurement and 1.08k considers the leakage current of a BJT for hFE and fixes a problem with Germanium BJTs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: toli on September 20, 2013, 08:40:40 pm
Damn! Now I should probably install 1.08k :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: moemoe on September 26, 2013, 07:38:55 am
The Arduino lacks the complete power management which the Transistor Tester got (optimized for battery usage).

I'd say 'partly'. You can still put a simple switch between the battery and the arduino.

Self-Power-Off won't work this way, but the sleepmodes can still be used. So it's more a question of convenience than a real problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 26, 2013, 12:07:29 pm
The Arduino lacks the complete power management which the Transistor Tester got (optimized for battery usage).

I'd say 'partly'. You can still put a simple switch between the battery and the arduino.

Self-Power-Off won't work this way, but the sleepmodes can still be used. So it's more a question of convenience than a real problem.

It's not impossible :-) Please see http://www.pighixxx.com/lavori/ardutester/ (http://www.pighixxx.com/lavori/ardutester/) for an Arduino version. But there are several differences due to the different hardware designs, starting with the voltage regulator (MCP1702 has a typical voltage tolerance of 0.4% at room temperature). And the dedicated hardware is less expensive than an Arduino Uno.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 30, 2013, 02:30:56 am
The Arduino lacks the complete power management which the Transistor Tester got (optimized for battery usage).

I'd say 'partly'. You can still put a simple switch between the battery and the arduino.

Self-Power-Off won't work this way, but the sleepmodes can still be used. So it's more a question of convenience than a real problem.

It's not impossible :-) Please see http://www.pighixxx.com/lavori/ardutester/ (http://www.pighixxx.com/lavori/ardutester/) for an Arduino version. But there are several differences due to the different hardware designs, starting with the voltage regulator (MCP1702 has a typical voltage tolerance of 0.4% at room temperature). And the dedicated hardware is less expensive than an Arduino Uno.
SainSmart Mega2560 R3 ATmega2560-16AU + ATMEGA16U2 + USB Cable For Arduino 2013 http://www.ebay.com/itm/271187169712?ss (http://www.ebay.com/itm/271187169712?ss)
$17.99 delivered and while it does not have a screen I was wondering if that would work as good and at least I could update its firmware very easily but the ready made ones do not have that capability that I could see.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 30, 2013, 09:22:10 am
I sent this one guy a message asking what version was his running and he sent me back
Quote
Dear friend,

Really so sorry. I do not know what the problem is. I hope you can understand
He doesn't even know what a version is be it either hardware or software and other ones did show a version number of 2.xx on the main board but they were hard to read at the angle of the picture.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bilko on September 30, 2013, 09:58:55 am
I really only need it for ESR (to know if a cap is good or bad,  the exact value is of no interest to me), for inductance (again, precision isn't very important for my current needs), and for transistor matching - it can do all this so its well worth the price.

1.07k got an improved ESR measurement and 1.08k considers the leakage current of a BJT for hFE and fixes a problem with Germanium BJTs.

I couldn't see 1.08k, has this been posted somewhere else ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 30, 2013, 12:51:03 pm
I couldn't see 1.08k, has this been posted somewhere else ?

1.08k is the current version and the current version is located at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) :-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 30, 2013, 01:06:53 pm
SainSmart Mega2560 R3 ATmega2560-16AU + ATMEGA16U2 + USB Cable For Arduino 2013 http://www.ebay.com/itm/271187169712?ss (http://www.ebay.com/itm/271187169712?ss)
$17.99 delivered and while it does not have a screen I was wondering if that would work as good and at least I could update its firmware very easily but the ready made ones do not have that capability that I could see.

I've found following tester clones including the LCD module:
- www.ebay.com/itm/131000917393?ss (http://www.ebay.com/itm/131000917393?ss) $18.55 + $ 0.99 shipping
- www.ebay.com/itm/271267317113?ss (http://www.ebay.com/itm/271267317113?ss) $12.89 + free shipping (no pads for ISP)

For most clones you just need to solder in a pin header for the ISP.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 30, 2013, 01:23:27 pm
SainSmart Mega2560 R3 ATmega2560-16AU + ATMEGA16U2 + USB Cable For Arduino 2013 http://www.ebay.com/itm/271187169712?ss (http://www.ebay.com/itm/271187169712?ss)
$17.99 delivered and while it does not have a screen I was wondering if that would work as good and at least I could update its firmware very easily but the ready made ones do not have that capability that I could see.

I've found following tester clones including the LCD module:
- www.ebay.com/itm/131000917393?ss (http://www.ebay.com/itm/131000917393?ss) $18.55 + $ 0.99 shipping
- www.ebay.com/itm/271267317113?ss (http://www.ebay.com/itm/271267317113?ss) $12.89 + free shipping (no pads for ISP)

For most clones you just need to solder in a pin header for the ISP.
What is an ISP? I know Internet Service Provider but that isn't something you can solder on a PCB.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on September 30, 2013, 02:02:09 pm
What is an ISP? I know Internet Service Provider but that isn't something you can solder on a PCB.
In System Programming, aka ISP, is one of the various hardware/software layers protocols for the programming of the ATMEL AVR line of microcontrollers, among the Bootloader programming, JTAG programming, HVPP (High Voltage Parallel Programming), HVSP (High Voltage Serial Programming), etc., all of which protocols are extensively documented in every AVR datasheets.

So, yes, it is perfectly feasible to solder an ISP header on a PCB. For example, here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg263699/#msg263699) you can see J3, which is the Bootloader (with the RxD/TxD/GND lines) / Power (with the GND/Vdd lines) Header.


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: bilko on September 30, 2013, 02:11:09 pm
I couldn't see 1.08k, has this been posted somewhere else ?

1.08k is the current version and the current version is located at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) :-)
Thanks for that :)
I suspected that, however I just wanted to check as I could not see any version info in the trunk, the readme files is for version 1.06k?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 30, 2013, 02:22:50 pm
What is an ISP? I know Internet Service Provider but that isn't something you can solder on a PCB.
In System Programming, aka ISP, is one of the various hardware/software layers protocols for the programming of the ATMEL AVR line of microcontrollers, among the Bootloader programming, JTAG programming, HVPP (High Voltage Parallel Programming), HVSP (High Voltage Serial Programming), etc., all of which protocols are extensively documented in every AVR datasheets.

So, yes, it is perfectly feasible to solder an ISP header on a PCB. For example, here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg263699/#msg263699) you can see J3, which is the Bootloader (with the RxD/TxD/GND lines) / Power (with the GND/Vdd lines) Header.


-George
Which is the ISP header?  I don't own an Arduino but I want one of these that are the most up to date but the sellers are worthless as they have zero knowledge.  It is One Hung Low at its best.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on September 30, 2013, 02:36:20 pm
I have never used the Arduino platform, so I could not answer your specific question. Neither can I speak for the various e-bay implementations; as you said it yourself, these e-bay people are sellers and they probably know nothing more that the price of their merchandise and their commission!

Now, in the example I have linked to in my previous message, I am using the Bootloader for programming, so there is no ISP header in the proposed PCB.

The ATMEL AVR ISP Header is a 6-pin link between the programmer and the target chip. This is the ATMEL AVR910 In-System Programming (http://www.atmel.com/images/doc0943.pdf) application note, describing a low cost AVR ISP programmer that uses the hardware SPI module the target chips have embedded for that purpose.


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 30, 2013, 05:11:56 pm
the readme files is for version 1.06k?

You'll find the current complete documentation (ttester.pdf) at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/) (unfortunately you have to download the whole directory).
Title: Re: $20 LCR ESR Transistor checker project
Post by: bilko on September 30, 2013, 05:56:46 pm
the readme files is for version 1.06k?

You'll find the current complete documentation (ttester.pdf) at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/) (unfortunately you have to download the whole directory).

Thanks, that's great !
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 30, 2013, 08:30:12 pm
The guy wrote me back and his response about having the revision number was "Because we are not suppliers, hope you can understand".

Utterly hopeless.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 30, 2013, 08:45:26 pm
The guy wrote me back and his response about having the revision number was "Because we are not suppliers, hope you can understand".

Utterly hopeless.

Don't worry! Solder in an ISP pin header and get an ISP programmer 8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 30, 2013, 09:41:46 pm
The guy wrote me back and his response about having the revision number was "Because we are not suppliers, hope you can understand".

Utterly hopeless.

Don't worry! Solder in an ISP pin header and get an ISP programmer 8)
Which one of these http://tinyurl.com/mt3ao3t (http://tinyurl.com/mt3ao3t)  and where do I get a header from?  Might just get that one that has it already but that is a HUGE price difference imo between the two I was linked.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 30, 2013, 09:47:52 pm
What is an ISP? I know Internet Service Provider but that isn't something you can solder on a PCB.
In System Programming, aka ISP, is one of the various hardware/software layers protocols for the programming of the ATMEL AVR line of microcontrollers, among the Bootloader programming, JTAG programming, HVPP (High Voltage Parallel Programming), HVSP (High Voltage Serial Programming), etc., all of which protocols are extensively documented in every AVR datasheets.

So, yes, it is perfectly feasible to solder an ISP header on a PCB. For example, here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg263699/#msg263699) you can see J3, which is the Bootloader (with the RxD/TxD/GND lines) / Power (with the GND/Vdd lines) Header.


-George
Which is the ISP header?  I don't own an Arduino but I want one of these that are the most up to date but the sellers are worthless as they have zero knowledge.  It is One Hung Low at its best.
www.ebay.com/itm/131000917393?ss (http://www.ebay.com/itm/131000917393?ss)
I take it that the last picture of the three at the left hand side those 10 holes is for a non existent, but easily added, header?

10 - 10 pin (2x5) headers for $1.85 http://tinyurl.com/kyk7kwk (http://tinyurl.com/kyk7kwk) delivered.

One thing I am noticing is that the LCD shield will never fit once the header is soldered in.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on September 30, 2013, 10:20:48 pm
Yes, it seems that it must be a socket for the 10-pin AVR ISP header.

Be careful with the ISP polarity though!
This is the pinout for the standard 6-pin and 10-pin AVR ISP headers:

(http://upload.wikimedia.org/wikipedia/commons/thumb/9/9f/Isp_headers.svg/220px-Isp_headers.svg.png)


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on September 30, 2013, 10:23:26 pm
Yes, it seems that it must be a socket for the 10-pin AVR ISP header.

Be careful with the ISP polarity though!
This is the pinout for the standard 6-pin and 10-pin AVR ISP headers:

(http://upload.wikimedia.org/wikipedia/commons/thumb/9/9f/Isp_headers.svg/220px-Isp_headers.svg.png)


-George
It looks like a 10 (2x5) header but I see no indication of which is pin 1 on that board.  As I said above I am a bit doubtful that the LCD shield will fit once an ISP header is added as the header is taller, I think, than is the LCD header it looks like.

After looking at the board and those pinouts of the ISP headers it appears that the header will face down in the picture as the bottom two holes the first hole to the left of the picture appears to be going to Vcc.

It looks like the RST pin is not connected.(http://ecx.images-amazon.com/images/I/51UcGCMY8sL.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on September 30, 2013, 11:05:46 pm
Quote
After looking at the board and those pinouts of the ISP headers it appears that the header will face down in the picture as the bottom two holes the first hole to the left of the picture appears to be going to Vcc.
This is probably right.

Quote
It looks like the RST pin is not connected.
Neither the four ground pins do! That is because this is a dual layer PCB, with the 'missing' traces existing at the other, opposite layer.

Regarding the LCD PCB, I am afraid that you are right: The ISP header pins are of the same height as the LCD header pins, and the ISP pins might hit (and short) the LCD resistors. Of course, you could trim the ISP pins height (push them gently, no more than a couple of millimetres, down through their plastic base assembly, and after soldering the header cut their excessive portions) and insulate the LCD PCB area that faces the ISP header.


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: senso on September 30, 2013, 11:25:31 pm
Or solder female headers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on September 30, 2013, 11:48:13 pm
Or a 5*2 pin 90° Degree header (http://www.google.com/search?um=1&newwindow=1&hl=en&tbm=isch&q=90%C2%B0+Degree+pin+header).


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on October 01, 2013, 02:01:47 am
Or a 5*2 pin 90° Degree header (http://www.google.com/search?um=1&newwindow=1&hl=en&tbm=isch&q=90%C2%B0+Degree+pin+header).


-George
Yes, that is exactly what I was thinking but couldn't find any on Ebay so my search will continue. http://www.ebay.com/itm/Dual-Rows-2-54mm-Pitch-10Pins-90-Degree-Angle-IDC-Pin-Headers-5-Pcs-/321218266576?pt=LH_DefaultDomain_0&hash=item4aca19c5d0 (http://www.ebay.com/itm/Dual-Rows-2-54mm-Pitch-10Pins-90-Degree-Angle-IDC-Pin-Headers-5-Pcs-/321218266576?pt=LH_DefaultDomain_0&hash=item4aca19c5d0)

Now, once I have that soldered in then I get an AVR (I guess the ones I showed are alright?) I just grab a sketch and upload it to it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on October 01, 2013, 03:01:01 am
Yes, you will need an AVR ISP programmer to upload the new firmware, which is a *.HEX file.

BUT, things are a little more complicated than that because the latest TransistorTester revisions have extended functionality and require the mega328 AVR microcontroller, which has 32 kB of FLASH memory. Most (if not all) of the chinese TransistorTester knock-offs have the cheaper and smaller mega168 that has 16 kB of FLASH memory only or, even worse, the even cheaper mega88 with 8 kB of memory or the older mega8. The latest firmware will only fit in 32 kB memory, if you want it to have full functionality; or else, you will have to recompile the project with some functions disabled (read the project files, I do not remember specific details) in order for the firmware to fit in FLASH memory sizes of less than 32 kB.

So, with the ISP programmer, you will firstly need to check which microcontroller is on board (since most of these knock-offs usually have their chip identification marks erased). If the programmer identifies the microcontroller to be a mega328, you will just have to load it with the latest firmware and you are done. If the chip is identified as a mega168/mega88/mega8, you will also need to change it with a mega328.


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on October 01, 2013, 03:20:31 am
Yes, you will need an AVR ISP programmer to upload the new firmware, which is a *.HEX file.

BUT, things are a little more complicated than that because the latest TransistorTester revisions have extended functionality and require the mega328 AVR microcontroller, which has 32 kB of FLASH memory. Most (if not all) of the chinese TransistorTester knock-offs have the cheaper and smaller mega168 that has 16 kB of FLASH memory only or, even worse, the even cheaper mega88 with 8 kB of memory or the older mega8. The latest firmware will only fit in 32 kB memory, if you want it to have full functionality; or else, you will have to recompile the project with some functions disabled (read the project files, I do not remember specific details) in order for the firmware to fit in FLASH memory sizes of less than 32 kB.

So, with the ISP programmer, you will firstly need to check which microcontroller is on board (since most of these knock-offs usually have their chip identification marks erased). If the programmer identifies the microcontroller to be a mega328, you will just have to load it with the latest firmware and you are done. If the chip is identified as a mega168/mega88/mega8, you will also need to change it with a mega328.


-George
The sellers are just too stupid to help and I know I don't do SMT so now I just need to find someone with some self respect and decency and BRAINS who tell you what is on it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on October 01, 2013, 05:15:35 am
Well, you can let the sellers remain ignorant or non-helping, and use your eyes, knowledge and good judgment instead!

After a brief search I found several e-bay Testers with a PDIP chip on board, which is most easy to be changed if it is not an m328.

What to look for in the pictures of the Testers that you will find:
- There should be a crystal on board, for the time-depended measurements accuracy.
- They should have 1% tolerant resistors. There are boards with 5% resistors; this is not good for accuracy but the critical resistors can easily be changed with 1% ones.
- This is not critical but there should be a golden-plated socket for the chip, for better contact with the chip pins. If there is a cheap socket you can either leave it as is or change it with a better one.
- There should be an ISP header or socket. If there is not, an ISP header can easily be fitted in an unpopulated PCB area with a hot-glue gun, and be connected through cables directly soldered to the four ISP lines of the chip socket pins and to the GND and Vcc lines.
- Make sure that the seller will ship to you *exactly* what you have ordered.

This is not a rule but, a better looking and more pleasing to the eyes PCB layout and construction is usually made by a better designer.


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on October 01, 2013, 05:40:48 am
Well, you can let the sellers remain ignorant or non-helping, and use your eyes, knowledge and good judgment instead!

After a brief search I found several e-bay Testers with a PDIP chip on board, which is most easy to be changed if it is not an m328.

What to look for in the pictures of the Testers that you will find:
- There should be a crystal on board, for the time-depended measurements accuracy.
- They should have 1% tolerant resistors. There are boards with 5% resistors; this is not good for accuracy but the critical resistors can easily be changed with 1% ones.
- This is not critical but there should be a golden-plated socket for the chip, for better contact with the chip pins. If there is a cheap socket you can either leave it as is or change it with a better one.
- There should be an ISP header or socket. If there is not, an ISP header can easily be fitted in an unpopulated PCB area with a hot-glue gun, and be connected through cables directly soldered to the four ISP lines of the chip socket pins and to the GND and Vcc lines.
- Make sure that the seller will ship to you *exactly* what you have ordered.

This is not a rule but, a better looking and more pleasing to the eyes PCB layout and construction is usually made by a better designer.


-George
Good things to look for but I am finding most of these sales are from the same handful of sellers that are selling a ton of them all at once so it looks like there is more than there really is.  What I do is not even look at the seller's name and scan down to the pics and descriptions and within 10 secs I can tell it is the same as a previous one I looked at.

You know I am beginning to wonder how many Chinese sellers Ebay really has as this is not the first product that seems like a ton of sellers with all sorts of different prices and even with some make offers (they never work for me) but they are all from the same handful of sellers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on October 01, 2013, 06:56:30 am
1. Looks like one of the nicer ones.  Be interesting to see that board revision number.
http://www.ebay.com/itm/151124228042 (http://www.ebay.com/itm/151124228042)

2. Similar but blue screen
http://www.ebay.com/itm/181225081033 (http://www.ebay.com/itm/181225081033)

3. Zif socketed one
http://www.ebay.com/itm/231056057317 (http://www.ebay.com/itm/231056057317)

4. Looks like a later board revision here pity no gutshot
http://www.ebay.com/itm/121184647718 (http://www.ebay.com/itm/121184647718)

5. Battery powered, USB
http://www.ebay.com/itm/390589763450 (http://www.ebay.com/itm/390589763450)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on October 01, 2013, 07:06:02 am
Notice all of those green boards are from the same people and are V2.2/2.3 but that red board is a bit intriguing though one of them (I forgot which one) had what I thought very lousy results as they showed what the value was and what it read.  Close but 10% close I think it was which is pretty bad (33uH read .03mH).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dark Prognosis on October 01, 2013, 07:52:03 am
Or a 5*2 pin 90° Degree header (http://www.google.com/search?um=1&newwindow=1&hl=en&tbm=isch&q=90%C2%B0+Degree+pin+header).


-George
I did a little more digging via the spec sheet as I was noticing something odd and I was correct.  The height is 9.1mm of a standard 10 (5x2) IDC connector and the height of the same connector at a 90 degree angle is 9.0mm.  So, the bloody thing is as deep as it is tall. :/
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on October 01, 2013, 08:31:35 am
Looks like one of the nicer ones.
I could not recommend something for which I do not have the precise specifications. This is what I can see and deduce from the pictures, with the devices numbered in the order they are presented:

- Numbers 3 and 4 seem to be more robust because they have their LCD PCB secured on the mainboard with bolts and spacers.
- Numbers 1, 2, 5 and probably 4 come with unknown chip (probably an m168) in TQFP package, and with ISP socket.
- Numbers 1 and 5 do not seem to have a crystal time-base, which is required for the time-depended measurements accuracy.
- Number 5 with the LiPo battery has an on-board DC-DC converter, that might increase electrical noise.
- Number 4 is called 'M8 transistor tester' (because of the mega8 it possibly has on board?) Is the chip in PDIP or in TQFP package? Does it have a crystal time-base?
- Number 3 has a mega328 in PDIP socketed on board and runs a firmware that seems to be more recent than the other ones. The m328 can be removed from the socket and be updated with an AVR ISP and a breadboard.

[...] So, the bloody thing is as deep as it is tall.
So, trimming the pins and insulating the LCD PCB might work.
But, what the reprogramming is good for if the chip is not an m328?

EDIT: By the way, I should warn you to be careful with the AVR Fuses because a wrong setting can brick the chip and its revival can be from difficult (by the injection of an external clock) to painfull (by desoldering and HVPP with a special HV programmer, like the ATAVRDRAGON).


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: darrylp on October 01, 2013, 09:20:35 am
Here is my socket, no problems with clearance.

(http://img.tapatalk.com/d/13/10/01/pazuje8u.jpg)

(http://img.tapatalk.com/d/13/10/01/hutubaze.jpg)


--
 Darryl

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 01, 2013, 12:35:29 pm
- They should have 1% tolerant resistors. There are boards with 5% resistors; this is not good for accuracy but the critical resistors can easily be changed with 1% ones.

The 680 and 470k Ohms resistors for the test pins should have a 0.1% tolerance. Or you could select matched ones and update the default values in config.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on October 01, 2013, 12:58:38 pm
We are in total agreement, dear Markus.

But, I was talking about Through-Hole resistors. It is almost next to impossible to find through-hole resistors of a better than 1.0% tolerance in the retail market (at least, over here, in Greece). On the other hand, SMT resistor chips of 0.1% (or 0.05% or even 0.01%) tolerance is not only feasible to find but it is also accessible and obtainable at a reasonable price (in Digi-Key/Mouser/etc.).


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 01, 2013, 01:52:27 pm
But, I was talking about Through-Hole resistors. It is almost next to impossible to find through-hole resistors of a better than 1.0% tolerance in the retail market (at least, over here, in Greece). On the other hand, SMT resistor chips of 0.1% (or 0.05% or even 0.01%) tolerance is not only feasible to find but it is also accessible and obtainable at a reasonable price (in Digi-Key/Mouser/etc.).

Reichelt sells 0.1% through-hole resistors (Yageo) for € 0.16 each in case if someone has problems with finding any and lives in the EU. Otherwise you could create through-hole resistors by adding some wire to the SMT resistors :-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on October 01, 2013, 02:33:03 pm
Reichelt: 680 Ohm (http://www.reichelt.com/Metal-0-1-100-Ohm-910-Ohm/MPR-680/3/index.html?&ACTION=3&LA=2&ARTICLE=13051&GROUPID=3103&artnr=MPR+680)/470 kOhm (http://www.reichelt.com/Metal-0-1-100-k-Ohm-1-00-M-Ohm/MPR-470K/3/index.html?&ACTION=3&LA=2&ARTICLE=12984&GROUPID=3105&artnr=MPR+470K)! This is interesting, thank you!
I did not know that, neither did I do any search in the wider EU market for such components, since I have learned how much it hurts to be purchasing very low quantities from the known component warehouses. Now I know better, thanks to you!

Well, what I did with what I was able to find locally, was to get 10 x 1% resistors of each (critical) value and to use the three of each value that I could match with the ohmmeter as close as possible to each other, updating at the same time the project configuration file resistor values with the actually measured ones. The result was not bad, giving me almost 0.1% match between the measurement readings of the same component that I tested using all the three combinations of the test-point pairs (TP1 to TP2, TP2 to TP3 and TP3 to TP1).


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: TonyGreene on October 07, 2013, 01:37:22 am
I bought a couple of these units off of Ebay - SamLove from China.  These units use the ATMEGA328P-PU in the long DIP form.  They do not have the 2.5V voltage reference on Pin 27, but they do have the 8 Mhz crystal and the bypass caps.

I did a test, right out of the box, and here is the results, with no calibration;

47pF 5% Mica         55pF            52pF
150pF 5% Mica         162pF            161pF
300pF 10% Mica         323pF            322pF
470pF 10% Mica         470pF            459pF
560pF 5% Mica         574pF            571pF
3000pf 2% Mica         3062pF         3040pF
4300pF 1% Mica         4392pF         4369pF
8200pf 1% Mica         8394pF         8347pF
11000pf 5% Mica         10.67nF         10.62nF
17000pF 2% Mica         17.27nF         17.17nF
.00604uF 3%            6060pF         6025pF
.00301uF 3%            3151pF         3136pF
.0243uF 3%            25.09nF         24.62nF
.0478uF 3%            48.31nF         47.44nF
.075uF 1%            75.98nF         75.5nF
.0768uF 1%            78.14nF         77.70nF
.183uF 2%            185.1nF 1.6o         182.2nF 1.2o
1.0uF 10%            1112nF .42o         1106nF .42o
1uF Tant            1051nF 4.3o .5%      1038nF 5.7o .6%
2uF Mylar            2216nF .25o         2203nF .24o
3uF Mylar            3143nF .22o         3124nF .21o
4uF Mylar            4151nF .22o         4127nF .21o
10uF Tant            diode 3.57V 11.5uF      diode 3.92V 11.2uF
1uF Mil Glass            990.1nF .91o .1%      979.3nF .89o .1%
100uF Electro            100.2uF .52o .4%      97.43uF .51o .5%
234uf 10% NP Aluminum Electro   230.9uF .23ohm 1.0%   223.7uF .21o 1.2%
470uF Electro            544.ouF .24o .5%      529.8uF .34o .7%
2000uF Electro         2154uF .2o .6%      2096uF .18o .6%
3300uF            3318uF .19o 1.5%      3249uF .21o 1.3%
8000uF Electro         8999uF .22o .6%      8779uF .20o .6%
10,000uF Electro         11.67mF .20o 1.6%      11.38mF .16o 1.6%

10uH               .5o .01mH         .4o .01mH
100uH               1.5o   .09mH         1.6o .09mH
2.5mH               20.0o   2.64mH      19.7o 2.61mH
30mH               3.1o 29.8mH         3.2o 30.1mH
44mH               55.7o 40.8mH         56.7o 40.5mH
50mH               46.7o 50.8mH         47.5o 50.8mH
120mH            158.8o 122mH      159.6o 123mH
250mH            32.8o 248mH         33.5o 247mH
720mH            44.3o 703mH         45.0o 701mH
2.3H               62.3o 7.46H         63.5o 7.75H

zero ohm .1% decade         .28o            .27o
.5 ohm decade         .66o            .79o
1 ohm decade            1.28o            1.31o
5 ohm decade            5.34o            5.51o
10 ohm decade         10.5o            10.7o
50 ohm decade         50.8o            51.7o
100 ohm decade         101.2o            103.1o
500 ohm decade         498.8o            499.2o
1K decade            1003o            1003o
5K decade            4957o            4888o
10K decade            9955o            9786o
40K decade            40.57K         41.30K

10K .1$ MF            9786o            9962o
162K .1% MF            161.8K         162.0K
300K .1% MF            300.2K         300.3K
499K .1% MF            499.2K         499.6K

100 ohm .05% WW         101.1o            102.9o
1K .01% WW            1003o            1003o
10K .01% WW         9955o            9788o
100K .01% WW         101.2K         103.0K
1M .01% WW            1002K            1002K
9M 1% WW            9215K            9032K

RS2761067 SCR 200V 6A      NPN transistor....
2N3440            B99 595mV         B100 663mV
2N3906            B190 674mV         B186 748mV
2N5415            B72 660mV         B70 659mV
IFR820 FET            N E MOS C958pf V+3.31V   c941pF 3.33V
MPF102 FET            N JFET 2.7mA gs 1.87   2.7mA gs1.89

1N4146            709mV 10pF         787mV 9pF
1N5400            604mV 84pF         642mV 82pF
1N6263            573mV 8pF         586mV 8pF
MBR10H100CT         363mV 363mV      369mV 369mV



Title: Re: $20 LCR ESR Transistor checker project
Post by: TonyGreene on October 07, 2013, 01:38:13 am
Another picture close up

These units are nice for us older folks, who can't see like we use to, it will make sure the parts are in the right ballpark before stuffing our boards.

I do plan to add the 2.5 volt reference and put the units in a case.

I think, but not sure that the software in these units are either 1.07 or 1.08.  The seller never could answer the question.  I would be nice to put the version in the bootup screen.

(added; as suggested below, I did the cal and its loaded with V1.07)

Title: Re: $20 LCR ESR Transistor checker project
Post by: gtroc71 on October 07, 2013, 02:05:52 am
Hey Tony, my tester displays the version at the end of the calibration process.
Don't know if that is just the version I have (105) but I assume it works with all  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 07, 2013, 12:48:21 pm
I did a test, right out of the box, and here is the results, with no calibration;

I strongly recommend to run the self-adjustment. It measures the resistance and capacitance of the probes (incl. the PCB), internal IO port resistance, offsets of the bandgap reference and analog comparator and so on. Those values/offsets are stored in the EEPROM and will be taken into account for all new measurements which will be more precise. Without the self-adjustment some default values are used and they might not match your tester very well.

Please run the self-adjustment, re-run your tests and compare the results. And you'll will see :-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rastro on October 07, 2013, 11:07:34 pm
Another picture close up

I do plan to add the 2.5 volt reference and put the units in a case.


Tony, I probably missed something what is the 2.5 volt reference you're referring to.  Is it a modification instead of internal 328 reference?
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: TonyGreene on October 08, 2013, 02:07:23 am
The 2.5V reference is discussed in chapter 2.1 and 2.4 of the V1.08 software, and maybe the same in previous versions.

Chapter 2.1 tells that an external voltage reference connected at pin PC4 can be used to check and calibrate the VCC voltage, but is not required for the basic operation of the Transistor/LCR tester.

Chapter 2.4 tells that sometimes with no connection to the pin, it may display unknown VCC voltage.  If this happens they recommend using a pullup resistor from the pin to VCC.  The pullup resistor keeps the processor from displaying the regulator output voltage.

The unit I received had no connection to pin 27.  I connected a 2.41K 0.5% resistor from the output of the +5 regulator to the cathode of the LM336Z-2.5 reference.  The anode of the reference is connected to ground.  Make a connection from the cathode of the reference to pin 27 of the ATmega328 and the unit will read the +5 volt regulator voltage.  And note this connection only works if you have the ATmega328 chip in the photo's I posted.  The connection is different depending on your ATmega328 chip package.

You don't need this, but its handy, you can run your battery all the way down until its starts affecting the +5 volt reference output.
Title: $20 LCR ESR Transistor checker project
Post by: Napalm2002 on October 08, 2013, 04:55:31 pm
Bought one. Really like it and is definitely worth the few bucks that it costs.
Title: $20 LCR ESR Transistor checker project
Post by: Napalm2002 on October 08, 2013, 04:59:34 pm
I was kicking around putting mine in an enclosure and putting leads on it. You did a nice job. Gonna have to get out the dremel tool and solder some stuff now
Title: Re: $20 LCR ESR Transistor checker project
Post by: TonyGreene on October 10, 2013, 12:22:34 am
Here is a test of one of my units, I call it serial number 1.  The unit is cased and self-calibrated.

Test start 10/9/2013 17:41 71.5F    12V Battery
Test End 10/9/2013 19:12  72.0F

LM395 Matched Pair Transistor   Side A       B=1.03K Uf=619mV   
Unit 1                               Side B      B=1.03K Uf=614mV

LM395                                    Side A      B=860  Uf=614mV
Unit 2                               Side B      B=870  Uf=609mV

2N3904            NPN      B=168  Uf=716mV
Tung-Sol ET-1         PNP      B=89  Uf=117mV
2N2222            NPN      B=170  Uf=665mV
2N2907A            PNP      B=161  Uf=628mV
2N3440            NPN      B=101  Uf=576mv
2N5415            PNP      B=62  Uf=664mV
2N3054            NPN      B=38  Uf=584mV
2N3772            RESISTOR   1.29O
2SD91               NPN      B=89  Uf=516mV

MPF102            N-JFET   I=2.1mA Vgs=1.50
IFR820              N-E-MOS     C=829pF   Vt=3.32V
IFR510            N-E-MOS   C=437pF  Vt=3.14V

1N6263            DIODE   Uf=585mV  C=0pF
1N4148            DIODE   Uf=710mV  C=0pF
1N4001            DIODE   Uf=664mV  C=13pF
NTE5812            DIODE   Uf=590mV  C=163pF
1N5404            DIODE   Uf=584mV  C=49pF
1N3002            DIODE   Uf=642mV  C=408pF
1N1183A            DIODE   Uf=512mV  C=0pf
MBR10H100CT  Dual Diode   2*DIODE   UF=368mV  370mV

LM336Z-2.5V         DIODE   Uf=2.03V  C=0pF
LM4041BZ1.2V         2*DIODE   Uf=1.23V  796mV

Green LED            DIODE   Uf=1.96V  C=4pF
Yellow LED            DIODE   Uf=1.85V  C=4pF
Red LED            DIODE   Uf=1.60V  C=18pF
Red LED            DIODE   Uf=2.35V  C=49pF

IS420 SCR            NPN      B=29 UF=497mV

1,000,000 .01% WW         Resistor   1002K
100,000 .01% WW         Resistor   99.45K
10,000 .01% WW         Resistor   10.08K
1,000 .01% WW         Resistor   1003
100 .05% WW         Resistor   99.8
752.768 .02%    WW         Resistor   753.7
again                     753.7
again                     753.7
again                     753.7
again                     753.7
1 .5% WW                  1.67
10 .5% WW                  10.4
Shorted                  .55
9,100,000 1% WW               9346K
27,000,000 1% WW               26.87M

10pF               Unknown
22pF               Unknown
32pF Mica 5%         Capacitor   32pF
47pF Mica 5%               48pF
100pF Mica 5%               105pF
120pF Mica                  118pF
150pF Mica 5%               151pF
180pf Mica 10%               189pF
301pF Mica                  310pF
360pF Mica 5%               364pF
470pF Mica                  467pF
560pF Mica 5%               556pf
3000pf Mica 2%               3024pF
8200pf Mica 1%               8128pF
11000pf Mica 5%               10.45nF
15000pF Mica 5%               14.39nF
17000pF Mica 2%               16.91nF
33000pF Mica 5%               33.35nF
2.0uF Mylar 12.5%               2128nF  ESR=.66o
4.0uF Mylar 2%               4054nF  ESR=.63o Vloss=.1%
234uf Alum Electro NP 10%            235.1uF  ESR=.61o  Vloss=1%
470uF Alum Electro               495.7uF  ESR=.39o  Vloss=1.2%
1000uf Alum Electro               922.2uF ESR=.65o Vloss=.5%
3300uf Alum Electro               3364uF ESR=.61o  Vloss=1.2%
8000uF Alum Elctro               8999uF  ESR=.56o  Vloss=1.3%
10,000uF Alum Electro            11.81mF  ESR.59o  Vloss=1.6%
1uF Tant                  1020nF  ESR9.6o  Vloss=.3%

10uH                     .7o  L=.01mH
100uH                     1.6o L=.10mH
2.5mH                     19.2o  L=2.52mH
44mH 3%                  54.8o  L=40.0mH
50mH audio                  44.8o  L=49.9mH
30mH telephone               3.3o  L=28.4mH
120mH military               166.3o L=121mH
250mH Telephone               32.5o  L=244mH
720mH                  43.9o  L=689mH
8.3H 61o                  61.5o  L=8.50H

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 10, 2013, 11:10:49 am
IS420 SCR            NPN      B=29 UF=497mV

Optical coupled TRIACs aren't supported yet :-)

Quote
Shorted                  .55

That's a little bit strange because the self-adjustment measures the resistance of the probes and the tester takes that into account when measuring resistors. Are you using probe leads? Have you done the self-adjustment with the probe leads attached?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 21, 2013, 08:59:55 pm
Firmware News

Karl-Heinz finished version 1.08k (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/)) with following highlights:
- support of DOG-M LCD modules with ST7036 controller
- measurement of leakage current for diodes and BJTs (used for hFE)
- 3 new UI languages
- several minor improvements

And I just released 1.10m (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)):
- 2.5V voltage reference (hardware option)
- protection relay for discharging caps (hardware option)
- Zener voltage measurement >4V (DC-DC boost converter hardware option)
- 16MHz MCU clock
Title: Re: $20 LCR ESR Transistor checker project
Post by: true on October 22, 2013, 03:24:43 am
Is there a page on differences between versions anywhere? Wiki? Something like that?

Should I make one? (not something I'd enjoy doing but it's info I would like to know anyway)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Flump on October 22, 2013, 07:36:19 am
Can someone link to the best one of these to get please ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 22, 2013, 01:02:19 pm
Is there a page on differences between versions anywhere? Wiki? Something like that?

There's no side-by-side comparison but most major differences are mentioned in the readme file of the m-version. A short ad hoc list for the m-version:
- no ESR (yet) and Vloss (caps)
- just two languages included
- no support for software UART (serial output)
- no support for alternative LCD module pins (stripboard version)
- just ATmega168 and 328
- UI with selectable hold mode (wait for key press) and menu
- PWM tool (select from several predefined frequencies and change the PWM ratio in 5% steps)
- several measurements differ in some details
- completely different logic for diode detection
- low resistance measurement (kind of :-)
- Zener tool (4-30/40V) is selected via menu
- IGBT detection (if 5V are sufficient)
- readable source code with tons of comments

Quote
Should I make one? (not something I'd enjoy doing but it's info I would like to know anyway)

We would keep you busy :-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 22, 2013, 01:14:11 pm
Can someone link to the best one of these to get please ?

The best one is the one you build yourself :-) Actually you could choose any clone but make sure that it has got an ATmega328. The 168 doesn't got enough flash to support all features. And the clones without ISP pin header or pads could be less convenient to update.
Title: Re: $20 LCR ESR Transistor checker project
Post by: A Hellene on October 22, 2013, 04:27:23 pm
Can someone link to the best one of these to get please ?
Here you are: This (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg299822/#msg299822) is what to look for and what to avoid, regarding a clone, and this (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg299866/#msg299866) is a deductive visual inspection round-up of five clones suggested by another fellow EEVBlogger; and this (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg263699/#msg263699) is what, for example, you can build.


-George
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on October 26, 2013, 09:39:22 am
I picked up a few of these.
Hopefully I can also get those free solder splashes on the LCD thrown in (just kidding).

I have a few questions to you guys who have been through this already:
1. Was there a consensus on the ISP header such as the one Darrylp mounted?
2. Since this may have a ATmega168. Is it possible to retrofit an ATmega328P, ATmega328 or socket in the same package?
3. How can I tell them apart? Are they essentially the same beast or need further mods?
4. Wheres a good resource for info on AVR ISP programming?
5. Anyone got a good place to purchase headers, chips and programming related parts from?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 26, 2013, 12:47:22 pm
I have a few questions to you guys who have been through this already:
1. Was there a consensus on the ISP header such as the one Darrylp mounted?
2. Since this may have a ATmega168. Is it possible to retrofit an ATmega328P, ATmega328 or socket in the same package?
3. How can I tell them apart? Are they essentially the same beast or need further mods?
4. Wheres a good resource for info on AVR ISP programming?
5. Anyone got a good place to purchase headers, chips and programming related parts from?

1. Use what fits :-)
2. Yes, same package, same pinout.
3. If you're talking about the ATmegas, just compile and flash the firmware for the 328 and enjoy the additional featues. No hardware mods are required. You can distinguish the types by the chip's signature (using an ISP programmer) if the markings are sanded off.
4. Look at http://www.atmel.com/ (http://www.atmel.com/) for datasheets and application notes (AVR910).
5. Please set your country in your profile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Frenchie on October 26, 2013, 03:28:45 pm
I've laid out a SMD board with the intention of soldering it directly onto the back of an LCD with a pin header. I figure the board layout might be useful to someone else, so the Gerbers are attached and the board is shared at OSHPark (http://oshpark.com/shared_projects/ir4NKmKE (http://oshpark.com/shared_projects/ir4NKmKE)).

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=64843)

I'm currently waiting on the 0603 0.1% resistors to arrive with my next digikey order. I've tested with 5% resistors and everything works okay (of course not as accurately as it would otherwise be). Shown below is a breadboard test, in the final configuration I intend to back to back the board with the display (ie top side facing out) and solder them together with a pin header. Plugging both into a breadboard lets me get at the through hole components if I need to.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=64846)

Changes:

A quick word of caution, this is my RevC board, I renumbered my schematic to match Karl-Heinz Kübbeler's annotation and took the opportunity to make a  few very minor position & routing changes. Everything passes ERC/DRC so there should be no issues with this revised layout but I've not built it up to check. PM me if you instead want gerbers for the RevB which I know works. Murphy got me with RevA and I swapped one of the transistor's pins
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stonent on October 26, 2013, 04:18:16 pm
I saw another one of these on Ebay that had some sort of rudimentary function generator. And now I can't find it. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on October 26, 2013, 08:16:54 pm
I saw another one of these on Ebay that had some sort of rudimentary function generator. And now I can't find it.

http://www.ebay.com/itm/161135107947 (http://www.ebay.com/itm/161135107947)

http://www.ebay.com/itm/321157000855 (http://www.ebay.com/itm/321157000855)

http://www.ebay.com/itm/150959457334 (http://www.ebay.com/itm/150959457334)


Nice work Frenchie on your PCB.  Did you make that yourself or?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stonent on October 26, 2013, 11:27:06 pm
I saw another one of these on Ebay that had some sort of rudimentary function generator. And now I can't find it.

http://www.ebay.com/itm/161135107947 (http://www.ebay.com/itm/161135107947)

http://www.ebay.com/itm/321157000855 (http://www.ebay.com/itm/321157000855)

http://www.ebay.com/itm/150959457334 (http://www.ebay.com/itm/150959457334)


Nice work Frenchie on your PCB.  Did you make that yourself or?

No, but I did see those as well. The one I saw showed them testing caps in the pictures, and also had a mp3-style oscilloscope connected to it in one of the pictures showing a wave form. But it did not have any BNCs. The LCD showed the frequency and voltage of the waveform it was outputting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stonent on October 29, 2013, 09:51:39 am
Hey I finally found it again. Looks like it does have a BNC on the side in one of the pictures.

http://www.ebay.com/itm/Digital-Tester-Resistance-Capacitance-Frequency-Meter-Oscilloscope-Generator-50-/290998783979?pt=LH_DefaultDomain_0&hash=item43c0e10feb (http://www.ebay.com/itm/Digital-Tester-Resistance-Capacitance-Frequency-Meter-Oscilloscope-Generator-50-/290998783979?pt=LH_DefaultDomain_0&hash=item43c0e10feb)

Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on October 29, 2013, 08:47:54 pm
I was thinking something along the lines of this.
I like the ZIF socket idea as you can just drop a component in or short test wires.
I would case mount it or put on a separate PCB to reduce opening and closing stresses. You can also change it later with no hassle.
9v battery compartment with door and external socket.

(http://i42.tinypic.com/2eulyqg.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 29, 2013, 10:11:53 pm
I was thinking something along the lines of this.
I like the ZIF socket idea as you can just drop a component in or short test wires.
I would case mount it or put on a separate PCB to reduce opening and closing stresses. You can also change it later with no hassle.
9v battery compartment with door and external socket.

Another nice idea! Someone has built a version with all hardware options (2.5V reference, relay and boost converter) and put the ZIF socket and contact pads on a small doughter board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: moemoe on October 30, 2013, 08:17:41 am
Another nice idea! Someone has built a version with all hardware options (2.5V reference, relay and boost converter) and put the ZIF socket and contact pads on a small doughter board.

I think this someone is me, see https://github.com/maugsburger/avr-component-tester
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on October 30, 2013, 08:56:58 am
I think this someone is me, see https://github.com/maugsburger/avr-component-tester

Got any photos of it complete?
Title: Re: $20 LCR ESR Transistor checker project
Post by: moemoe on October 30, 2013, 09:14:30 am
Got any photos of it complete?

How many do you want? :D

http://www.mikrocontroller.net/attachment/191030/ttpl.jpg (http://www.mikrocontroller.net/attachment/191030/ttpl.jpg)
http://www.mikrocontroller.net/attachment/195731/Transistortester_AVR_C_defekt.jpg (http://www.mikrocontroller.net/attachment/195731/Transistortester_AVR_C_defekt.jpg)
http://www.mikrocontroller.net/attachment/193735/transtest.jpg (http://www.mikrocontroller.net/attachment/193735/transtest.jpg)
http://www.mikrocontroller.net/attachment/193128/ttester.jpg (http://www.mikrocontroller.net/attachment/193128/ttester.jpg)
http://www.mikrocontroller.net/attachment/192882/20131003_054944.jpg (http://www.mikrocontroller.net/attachment/192882/20131003_054944.jpg)
http://www.mikrocontroller.net/attachment/191023/tt2.jpg (http://www.mikrocontroller.net/attachment/191023/tt2.jpg)
http://www.mikrocontroller.net/attachment/189066/tt.jpg (http://www.mikrocontroller.net/attachment/189066/tt.jpg)
http://www.mikrocontroller.net/attachment/192834/IMG_20131002_161938.jpg (http://www.mikrocontroller.net/attachment/192834/IMG_20131002_161938.jpg)

Just seeing that I don't have the mentioned ZIF daugher board, but it should be possible to add one without problems, just expand the SMD daughter board to the left and add a ZIF socket there.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stonent on October 30, 2013, 09:44:52 am
I didn't know cat droppings came in 0.025uF ratings.  :-DD. I don't think that I've seen a brown capacitor before with a round end.

But I do like the board and also how you used a bare LCD.
Title: Re: $20 LCR ESR Transistor checker project
Post by: moemoe on October 30, 2013, 12:02:03 pm
Most of the pictures are taken by other users at mikrocontroller.net, I just did a batch order of these PCBs.

I didn't know cat droppings came in 0.025uF ratings.  :-DD. I don't think that I've seen a brown capacitor before with a round end.

It's from an old tube radio and quite dead (see vloss), therefore the capacity measurement failed and shows a much too high capacity.

But I do like the board and also how you used a bare LCD.

In fact this is not a bare LCD, but a dogm http://www.lcd-module.de/pdf/doma/dog-m.pdf (http://www.lcd-module.de/pdf/doma/dog-m.pdf)

Karl-Heinz finished version 1.08k (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/)) with following highlights:
- support of DOG-M LCD modules with ST7036 controller
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 30, 2013, 02:08:19 pm
Just seeing that I don't have the mentioned ZIF daugher board, but it should be possible to add one without problems, just expand the SMD daughter board to the left and add a ZIF socket there.

IIRC the PCB I mentioned is from someone in the Ukraine, but yours is also nice! It even includes the PWM driver for the backlight ;-)

PS: A suggestion for a bench DIY version can be found at http://www.mikrocontroller.net/svnbrowser/transistortester/Hardware/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Hardware/Markus/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stonent on November 04, 2013, 08:37:50 am
Looks like someone was on to us for carefully scrutinizing chosen parts.

http://www.ebay.com/itm/NEW-Transistor-Tester-Diode-Triode-Capacitance-ESR-resistance-Meter-MOS-PNP-NPN-/221280589574?pt=LH_DefaultDomain_0&hash=item338559d706 (http://www.ebay.com/itm/NEW-Transistor-Tester-Diode-Triode-Capacitance-ESR-resistance-Meter-MOS-PNP-NPN-/221280589574?pt=LH_DefaultDomain_0&hash=item338559d706)

 :-BROKE
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 04, 2013, 02:08:05 pm
Looks like someone was on to us for carefully scrutinizing chosen parts.

http://www.ebay.com/itm/NEW-Transistor-Tester-Diode-Triode-Capacitance-ESR-resistance-Meter-MOS-PNP-NPN-/221280589574?pt=LH_DefaultDomain_0&hash=item338559d706 (http://www.ebay.com/itm/NEW-Transistor-Tester-Diode-Triode-Capacitance-ESR-resistance-Meter-MOS-PNP-NPN-/221280589574?pt=LH_DefaultDomain_0&hash=item338559d706)

I like the design with the banana connectors (2mm?) and the ZIF adapter! But, as always, there's no documentation. Has anyone, who bought one of tester clones, ever received a manual or a link to the project webpage? 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on November 08, 2013, 01:01:13 am
The one I just brought for $25 is a blue back-lite version 2.4 board dated 2013/07/01 with ATmega168V 10AU
Draws 26mA at idle and 1.3uA settling down to 0.7uA when auto off.

I would not recommend it yet, requires further testing. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on November 10, 2013, 12:16:52 am
Just found my first bad cap with my ESR meter. A compact fluorescent lamp failed and I could hear a cap complaining.  After butchering the case got 3045nF with ESR of 4.8 Ohms on the 3uF 400v electrolytic (Aishi).  A 5% 1 Ohm load resistor was also reading 1.2 Ohms.
Title: Re: $20 LCR ESR Transistor checker project
Post by: cib3k on November 10, 2013, 09:59:56 pm
Hi guys, what do you think about this:
http://www.ebay.co.uk/itm/DC12-Transistor-Tester-resistance-Meter-MOS-PNP-NPN-Diode-Triode-Capacitance-ESR-/290944824363 (http://www.ebay.co.uk/itm/DC12-Transistor-Tester-resistance-Meter-MOS-PNP-NPN-Diode-Triode-Capacitance-ESR-/290944824363?pt=LH_DefaultDomain_0&hash=item43bda9b42b)

It seems to already have an ATmega328, 0.1% resistors, 8MHz crystal and software version 1.07(k).
What's unusual is the built-in 9v battery and a DC power jack for 7.5-12v.
I'm not sure what this means: "Fuse, from low to high: F7DCF9".

The overview seems translated with Google Translate from this chinese page (http://item.taobao.com/item.htm?spm=a1z10.1.w4004-737437924.2.rNCbAy&id=17620914059). The pictures are standard pictures that also appear on other ebay auctions and seem obsolete compared to the stated capabilities of the tester. There's also a manual for a digital controller (REX-C100) that doesn't seem to have anything to do with the tester.

At the moment it would be difficult for me to just build a tester by myself - for various reasons. So I need to buy one, but I'm torn between this one and the one that Tony bought (http://www.ebay.co.uk/itm/Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-R-C-L-M328-/121183715380?pt=LH_DefaultDomain_0&hash=item1c371cc034). The latter also has ATmega328/8MHz crystal/software 1.07, but no 0.1% resistors and no built-in battery. I'm not sure if the 0.1% resistors make much difference, and I'm worried that the built-in battery/DC power jack might add some unnecessary circuitry that might increase electrical noise. What do you think?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 11, 2013, 01:50:42 pm
Hi guys, what do you think about this:
http://www.ebay.co.uk/itm/DC12-Transistor-Tester-resistance-Meter-MOS-PNP-NPN-Diode-Triode-Capacitance-ESR-/290944824363 (http://www.ebay.co.uk/itm/DC12-Transistor-Tester-resistance-Meter-MOS-PNP-NPN-Diode-Triode-Capacitance-ESR-/290944824363?pt=LH_DefaultDomain_0&hash=item43bda9b42b)

I like the design with the banana connectors and the ZIF adapter.

Quote
It seems to already have an ATmega328, 0.1% resistors, 8MHz crystal and software version 1.07(k).
What's unusual is the built-in 9v battery and a DC power jack for 7.5-12v.
I'm not sure what this means: "Fuse, from low to high: F7DCF9".

The current k-version is 1.08k (1.09 is under development) and "F7DCF9" describes the fuse settings, which seem to be slighly off. The recommended fuse settings for a 328 with 8MHz crystal are hfuse 0xd9, efuse 0xfc and lfuse 0xf7. Someone mentioned that the boxed tester clone lacks an ISP header.

Quote
At the moment it would be difficult for me to just build a tester by myself - for various reasons. So I need to buy one, but I'm torn between this one and the one that Tony bought (http://www.ebay.co.uk/itm/Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-R-C-L-M328-/121183715380?pt=LH_DefaultDomain_0&hash=item1c371cc034). The latter also has ATmega328/8MHz crystal/software 1.07, but no 0.1% resistors and no built-in battery. I'm not sure if the 0.1% resistors make much difference, and I'm worried that the built-in battery/DC power jack might add some unnecessary circuitry that might increase electrical noise. What do you think?

I'd buy the boxed one. It's got a nice box with nice banana connectors (2mm?) and the 0.1% resistors. The bare one lacks an ISP header, maybe the boxed one too. 1% resistors work also fine if they are matched and you've built a custom firmware with the resistor values updated in config.h. Additional power circuitry isn't a problem, there's a version powered by coin cells via a boost converter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on November 12, 2013, 02:26:09 am
I have a 475K 630V polyester capacitor that's reading 47.28nF shouldn't it be 4700nF (4.7uF)?  Any ideas?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 12, 2013, 12:26:46 pm
I have a 475K 630V polyester capacitor that's reading 47.28nF shouldn't it be 4700nF (4.7uF)?  Any ideas?

Do you got similar problems with other caps too or just with that one?
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on November 12, 2013, 03:48:17 pm
Those versions don't have ISP headers as the Processor is in a Socket DIP package and not SMD like other versions with the 128. Just take the chip out and reprogram it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on November 12, 2013, 10:55:54 pm
Do you got similar problems with other caps too or just with that one?

Wondering why it would be out by almost exactly a factor of 100x.  Just this one so far I'll test some more, might be faulty and a coincidence.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sync on November 12, 2013, 11:04:33 pm
How big is it? A 4.7uF 630V film cap is huge. About 3-4cm.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on November 13, 2013, 03:21:41 am
It's small 4x5x2mm it says 475K 630V on it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 13, 2013, 12:57:51 pm
It's small 4x5x2mm it says 475K 630V on it.

Or maybe ".475K" ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: sync on November 13, 2013, 02:02:00 pm
It's small 4x5x2mm it says 475K 630V on it.
It's too small for a 4.7uF 630V film cap. The transistor tester is probably right with 47nF. I have no idea why it's marked 475K.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stonent on November 13, 2013, 08:08:21 pm
Maybe a 475k ohm resistor with close wrapped wires with a break in them causing a capacitance? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: cib3k on December 01, 2013, 09:05:03 pm
I bought the one from here (http://www.ebay.co.uk/itm/DC12-Transistor-Tester-resistance-Meter-MOS-PNP-NPN-Diode-Triode-Capacitance-ESR-/290944824363?pt=LH_DefaultDomain_0&hash=item43bda9b42b).

Here's how it looks inside:

  (http://img237.imagevenue.com/loc538/th_925389645_11_122_538lo.jpg) (http://img237.imagevenue.com/img.php?image=925389645_11_122_538lo.jpg) (http://img283.imagevenue.com/loc549/th_925391323_22_122_549lo.jpg) (http://img283.imagevenue.com/img.php?image=925391323_22_122_549lo.jpg)
     

I've labeled some of the components, in the pictures.

The values of the resistors, in KOhms, are the following:
R1: 0.680, R2: 470, R3: 0.680, R4: 470, R5: 0.680, R6: 470, R7: 10, R8: 32, R9: 3.3, R10: 27, R11: 100, R12: 10, R13: 3.3, R14: 0.56

R1-R6 are 0.1%, R7-R14 are 1%.

The ESR values of the Rubycon electrolitics (16V, 10uF) are 4.3 and 4.7 Ohms. They're high, but could be normal, according to some ESR charts. I couldn't find any official Rubycon documentation with ESR values.

The version of the board is 2.10 from 2013.06.20. Which seems rather odd, since 2.10 is an old version. I think I've seen a board labeled v2.10 with a 2012 date on it. There are also boards labeled v2.2, v2.4 and v3.0. So did they use an old hardware layout and slapped a 2013 date on it? I'll have to look more into it.

Anyway, it lacks an ISP header (not a problem) and the 2.5 volt reference. Anything else you notice?

I haven't properly tested yet, I'm a beginner and I don't have many components lying around.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on December 01, 2013, 09:22:17 pm
Thanks for the nice write up and pictures.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 02, 2013, 12:56:40 pm
The ESR values of the Rubycon electrolitics (16V, 10uF) are 4.3 and 4.7 Ohms. They're high, but could be normal, according to some ESR charts. I couldn't find any official Rubycon documentation with ESR values.

Don't worry about them! Standard electrolytics are fine too.

Quote
Anyway, it lacks an ISP header (not a problem) and the 2.5 volt reference. Anything else you notice?

As long as you got an accurate voltage regulator the 2.5V reference doesn't give any benefits. It's more useful for a 7805 or 78L05. The PCB looks fine

Quote
I haven't properly tested yet, I'm a beginner and I don't have many components lying around.

Happy dumpster diving :-) E-junk is a good source for salvaging parts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kavaelect on December 11, 2013, 11:25:34 pm
Hi guys. Bought one to these testers and only did a few component tests when it started to display the word  "Cell!" every time now.

Tried replacing battery, shorting all three test points to enter self test mode but nothing I do has made a difference.
Would love some help to resolve the issue.

Searched the internet for info but can't seem to find anything helpful yet.

BTW....have already bought a new one on ebay and still waiting for its arrival.

I am desperately keen to find a fault in my NAD M15 surround sound decoder.

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 12, 2013, 03:15:07 pm
Hi guys. Bought one to these testers and only did a few component tests when it started to display the word  "Cell!" every time now.

The tester tries to discharge what's connected to the probe pins before starting the tests. The default limit is about 3mV. Any higher voltage will cause the warning "Cell!". Have you checked some parts in circuit or a charged cap? If the tester worked fine before I'd assume that one of the MCU inputs for the probe pins might be toasted.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on December 16, 2013, 10:12:06 pm
I made the Markus Frejek's AVR component tester, too.
Component tester with ATmega32 (https://www.youtube.com/watch?v=Qgc11si4obQ#)
http://www.mikrocontroller.net/articles/AVR-Transistortester (http://www.mikrocontroller.net/articles/AVR-Transistortester)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 17, 2013, 04:14:16 pm
I made the Markus Frejek's AVR component tester, too.
http://www.mikrocontroller.net/articles/AVR-Transistortester (http://www.mikrocontroller.net/articles/AVR-Transistortester)

The original project is a tad outdated :-) You'll find the successor at http://www.mikrocontroller.net/articles/AVR_Transistortester (http://www.mikrocontroller.net/articles/AVR_Transistortester) offering much more features.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on December 18, 2013, 01:26:35 am
Yes, but that did not work with my ATmega32.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stonent on December 18, 2013, 11:18:40 am
Quote
A connected capacitor can be measured in the range 35pF to 100MF with a resolution of up to 1 pF

Cool 100MegFarad. Will come in handy testing the decoupling caps at Comanche Peak. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 18, 2013, 01:46:58 pm
Quote
A connected capacitor can be measured in the range 35pF to 100MF with a resolution of up to 1 pF

Cool 100MegFarad. Will come in handy testing the decoupling caps at Comanche Peak. :)

:-) The upper limit is 100mF. The highest value I've tested so far is 22mF and the m-firmware goes down to 1pF if the input capacitance including probe leads exeeds 5pF (should be always the case) and the self-adjustment is done.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on December 28, 2013, 01:52:25 pm
Will this "cheapo" ISP programmer be capable of programming the ATMega168P & ATMega328/P MCs ?

http://www.ebay.com/itm/USB-ISP-Programmer-For-ATMEL-AVR-ATMega-ATTiny-51-Development-Board-New-/390641137707?pt=AU_B_I_Electrical_Test_Equipment&hash=item5af406b82b (http://www.ebay.com/itm/USB-ISP-Programmer-For-ATMEL-AVR-ATMega-ATTiny-51-Development-Board-New-/390641137707?pt=AU_B_I_Electrical_Test_Equipment&hash=item5af406b82b)

It is listed as capable for the ATMega168 (non-P).
Title: Re: $20 LCR ESR Transistor checker project
Post by: jav on December 28, 2013, 03:09:39 pm
Will this "cheapo" ISP programmer be capable of programming the ATMega168P & ATMega328/P MCs ?

http://www.ebay.com/itm/USB-ISP-Programmer-For-ATMEL-AVR-ATMega-ATTiny-51-Development-Board-New-/390641137707?pt=AU_B_I_Electrical_Test_Equipment&hash=item5af406b82b (http://www.ebay.com/itm/USB-ISP-Programmer-For-ATMEL-AVR-ATMega-ATTiny-51-Development-Board-New-/390641137707?pt=AU_B_I_Electrical_Test_Equipment&hash=item5af406b82b)

It is listed as capable for the ATMega168 (non-P).
Yes. Works fine. I have one of those and it's an USBasp  (http://www.fischl.de/usbasp/)clone. Mine came with an old firmware (2007), but as I ordered two, I used one to update the other.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on December 28, 2013, 04:31:30 pm
Will this "cheapo" ISP programmer be capable of programming the ATMega168P & ATMega328/P MCs ?

http://www.ebay.com/itm/USB-ISP-Programmer-For-ATMEL-AVR-ATMega-ATTiny-51-Development-Board-New-/390641137707?pt=AU_B_I_Electrical_Test_Equipment&hash=item5af406b82b (http://www.ebay.com/itm/USB-ISP-Programmer-For-ATMEL-AVR-ATMega-ATTiny-51-Development-Board-New-/390641137707?pt=AU_B_I_Electrical_Test_Equipment&hash=item5af406b82b)

It is listed as capable for the ATMega168 (non-P).
Yes. Works fine. I have one of those and it's an USBasp  (http://www.fischl.de/usbasp/)clone. Mine came with an old firmware (2007), but as I ordered two, I used one to update the other.
Thanks.

Another question - On my SMD TransistorTester unit I'm trying to replace the ATMega168P (TQFP-32) to its drop-in replacement - the ATMega328P. Found (in Ali-Express) the ATMega328P-AU (10 Pcs for $15). Is the *-AU part OK ?

http://www.aliexpress.com/cp/compare-atmega328.html (http://www.aliexpress.com/cp/compare-atmega328.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 28, 2013, 08:26:35 pm
Another question - On my SMD TransistorTester unit I'm trying to replace the ATMega168P (TQFP-32) to its drop-in replacement - the ATMega328P. Found (in Ali-Express) the ATMega328P-AU (10 Pcs for $15). Is the *-AU part OK ?

Should be fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on December 28, 2013, 09:52:49 pm
10x !
Title: Re: $20 LCR ESR Transistor checker project
Post by: Benik3 on December 30, 2013, 12:31:40 am
There is a new firmware 1.10 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 08, 2014, 06:34:41 am
ive purchased one of these on ebay and want to add m328 but have trouble finding latest hex. the mikro site is a hodge podge of confusing tex and hex files with line numbers and dont resemble any file type that avrdude recognizes. can someone tell me how to get a normal hex file there or link to another location? im mostly interested in inductance and milliohms, your help here would be greatly appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 08, 2014, 02:04:47 pm
ive purchased one of these on ebay and want to add m328 but have trouble finding latest hex. the mikro site is a hodge podge of confusing tex and hex files with line numbers and dont resemble any file type that avrdude recognizes. can someone tell me how to get a normal hex file there or link to another location? im mostly interested in inductance and milliohms, your help here would be greatly appreciated.

Unfortunately the website doesn't support direct download of individual files. If your tester matches the standard design please go to  http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/) and click "Download GNU tarball" for the tar.gz archive of the selected directory.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 08, 2014, 09:53:54 pm
thank you. that is what i needed to know. it wasnt obvious to me what tarball meant.  i hope the cheap version i got on ebay ($9 bid) will allow me to do inductance and low ohms measurements i need. specially nice are the smd pads on that board.

my plan is, once its tested with 9v battery, will try to convert to 5v dc benchtop supply. hopefully just tying the battery check adc input high will disable any low voltage warning. thanks again for helping.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 09, 2014, 05:46:14 pm
my plan is, once its tested with 9v battery, will try to convert to 5v dc benchtop supply. hopefully just tying the battery check adc input high will disable any low voltage warning. thanks again for helping.

You're welcome! If you're going for a direct 5V power supply I recommend to consider to add a 2.5V voltage reference. The low voltage warning/power-off can be disabled in the firmware (adjust values in config.h and recompile the source). Or a 7.5-12V supply would also be fine (based on the LDO regulator).
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 09, 2014, 07:25:35 pm
i guess you want 2.5v ref because dc supply is noisy and not stable? specially usb cable from pc in my case. i do have lm336 if that seems to be a problem. high accuracy is not important to me but i would like to measure lower inductance and lower capacitance. i guess soldering a 27pf and subtracting would work for caps but what about lower inductance?

would 20mhz xtl instead of 8mhz improve ability to measure lower inductance?

can you describe the alorithm used for measuring inductance?

minimum hardware is two 680r and two 470k?

compiling is not convenient atm but i am set up for atmel asm and would like to experiment.

edit: nevermind... i found all info needed on inductance algorithm in section 5.4 of document "ttester_eng106k.pdf". thanks for an excellent design.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 10, 2014, 01:20:47 pm
i guess you want 2.5v ref because dc supply is noisy and not stable? specially usb cable from pc in my case. i do have lm336 if that seems to be a problem. high accuracy is not important to me but i would like to measure lower inductance and lower capacitance. i guess soldering a 27pf and subtracting would work for caps but what about lower inductance?

The reason is the accuracy of the supply voltage. With a MCP1702 as LDO regulator you get 5V +/- 0.4%. Your PSU might deliver 4.7V or 5.3V and the voltage reference helps to determine the offset of the supply voltage. The tester will then compensate that for the measurements. A LM4040 would be a nice voltage reference. The LM366 is a hex sense amp ;-) The k-firmware supports capacitance measurements starting at about 30-35pF and the m-firmware at about 5pF. For measuring low inductance you'll need a proper LCR meter.

Quote
would 20mhz xtl instead of 8mhz improve ability to measure lower inductance?

The maximum clock rate currently supported by the firmware is 16MHz. The higher clock rate increases the timer resolution but that doesn't help much with low inductances (just a little bit). To measure lower inductances a higher test current would be needed. The inductance measurement is actually a nice by-product because the circuit wasn't designed for that. Other measurement methods are more suitable for supporting a larger range of values.

Quote
minimum hardware is two 680r and two 470k?

Three each. At the moment Karl-Heinz is testing also lower resistor values to gain higher test currents which improve some measurements.


Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on January 10, 2014, 02:00:32 pm
Do anyone have any link to one of these that have the 328 microcontroller?, and possibly not one that is sanded down, but maybe all still are ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 10, 2014, 02:12:38 pm
The LM366 is a hex sense amp ;-)

you misread. its lm336 which is 2.5v reference. ive been using them for years. not particualrly accurate but thats not important atm. i do have a couple 4040 but they are expensive and i got hundreds of lm336 in the junk box. in fact because accuracy is not needed at this stage i will probably not use any reference. im just thinking of throwing something quick together while waiting for the ebay one to arrive.

The maximum clock rate currently supported by the firmware is 16MHz.

right. my intent was to experiment with a basic asm version but now i see that inductance feature will never get down to the nanohenry range so will skip that idea. ill maybe build an oscillator type but even that may not be practical for the 433mhz and 2.4ghz indictors im dealing with. idk.

Three each.

if i only wire up 2 ea will it still perform as a two terminal tester? resistors, diodes, caps, coils? or does it check for all 6? right now im trying to throw together some minimum hardware till the one with full circuit and  0.1% resistors arrives.

i have one last question. does the hex file you gave me support serial? its mentioned in the diagram. i really want to build a usb/ftdi powered version like in the to-do list of that pdf. it would avoid the lcd and complicated power ckt. im hoping one of these can be built with 4-5 wires and couple components instead of dozens. ie minutes to build instead of hours/days. the fancy unit may not arrive for weeks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 10, 2014, 02:19:53 pm
Do anyone have any link to one of these that have the 328 microcontroller?, and possibly not one that is sanded down, but maybe all still are ?

a quick search on ebay for "transistor tester" will come up with hundreds of links. many clearly show mega328. generally it looks like the $16-$20 ones are m328. the $8-$12 ones may be m8 or m328. seller says the one i got for $9 is m328 but ive learned not to believe a word. ive got large supply of m328 anyway so its not important in my case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on January 10, 2014, 02:48:07 pm
ok, I thought most of the used the 168, but it's just a chipswap if so happens, then it should be fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 10, 2014, 03:06:42 pm
i think you are right, a lot of the middle priced ones seem to be m168. im not sure theres any practical difference at this stage of firmware except m8 definitely dont work with latest version. according to sellers the surface mount units all use the bigger chips but i would avoid them in case of bricking. the one i bought has no isp pads so thats another reason for socket. most ebay ads have photos showing the board so that helps.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on January 10, 2014, 03:30:38 pm
Earlier in this thread I think someone published links to ones that was sure to be the newer one with the 328, but they are old links, so i was hoping that someone had some that was checked recently.
I see there are three of four types:
1) one with ZIF socket, and avr in dip: http://www.ebay.com/itm/271366797178 (http://www.ebay.com/itm/271366797178)

2) one that is boxed: http://www.ebay.com/itm/181109931348 (http://www.ebay.com/itm/181109931348)

3)  this one seems to have an 8L http://www.ebay.com/itm/271367115286 (http://www.ebay.com/itm/271367115286)

4) smd version, 168: http://www.ebay.com/itm/181161606431 (http://www.ebay.com/itm/181161606431)

And probably lots of other variations too..
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 10, 2014, 07:07:46 pm
the 8$ one in your 3rd link is exactly what ive got coming. he swears its m328 but thats doubtful. he also said it was backlit but that is probably not true either. personally i dont care either way because i got tubes of m328 and backlit displays are cheap.

what i would really like to do is, while waiting, build a stripped down version with nothing more than four 5% resistors with power and txd going to a pc serial adapter. im wondering if that will work with the hex file posted above. it would also be nice if internal pull-ups were active so i dont have to wire external ones.

edit: i connected only 5v and pc4 and every time i reset get the following characters at 19200bps:

12V
 0V 1.32V

or

13v
5.02 VBF C

or

16v
F C

probably what it thinks is battery and some "ghost" component or self test warning. lots of garbage characters too. so thats a good sign. pretty good for NO external components at all. very encouraging so next im going to hook up some resistors and a cap across tp1-2 then see what comes out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on January 10, 2014, 10:01:33 pm
Based on description, it also seems like this is using same code?

but, support for big screen, that is something the chinese have added?

http://www.ebay.com/itm/181164691633 (http://www.ebay.com/itm/181164691633)

Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 11, 2014, 01:13:25 pm
yes, i saw those. also the ones with signal generator built in. $50 is too much though imo.

so i wired the six resistors, tied pc4 & pc5 hi, and pullup on the button. it seems to be working after a fashion but not quite behaving as described in ttester_eng106k.pdf. on reset or button push with .1uf inserted i sometimes get a message "not calibrated" followed by confusing instructions to short terminals and/or plug in 100nf cap.  a couple times i got "100nf" reading but only one or two times at the beginning and not since. usually just a few cryptic letters.

this never happens when ports are shorted together as described in manual. sometimes i do get "0ohms 0ohms" which makes sense but, again, not reliable. no hint of self-test or calibration.

it might be wiring error or bad contacts or who knows what else. it does look like there are issues with the serial routines. lots of blank spaces and odd characters. im using a crystal and spacing is very consistent so unlikely a baud problem. maybe set for some oddball terminal protocol. it would be nice if it just printed a line or two with crlf in industry standard vt100/hyperterminal format.

i wont be able to play with code til vacation is over in couple weeks and it will be interesting to see how the ebay unit behaves when that arrives.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 11, 2014, 03:16:38 pm
you misread. its lm336 which is 2.5v reference.

I see.

Quote
if i only wire up 2 ea will it still perform as a two terminal tester? resistors, diodes, caps, coils? or does it check for all 6? right now im trying to throw together some minimum hardware till the one with full circuit and  0.1% resistors arrives.

For self-adjustment all three are needed. And I think it might break some tests.

Quote
i have one last question. does the hex file you gave me support serial? its mentioned in the diagram. i really want to build a usb/ftdi powered version like in the to-do list of that pdf. it would avoid the lcd and complicated power ckt. im hoping one of these can be built with 4-5 wires and couple components instead of dozens. ie minutes to build instead of hours/days. the fancy unit may not arrive for weeks.

Please see the Makefile:
CFLAGS += -DWITH_UART

The software UART is enabled for that firmware image.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 11, 2014, 04:53:08 pm
yes, since that post i wired the six resistors, tied pc4 & pc5 hi, and pullup on the button. it seems to be working after a fashion but not quite behaving as described in ttester_eng106k.pdf. in fact i bult two units like that. whats strange is different m328 work differently.

is it necessary to program the eeprom file?

i also see lots of signals that are not serial appearing on pc3. it is consistent though so dont look like noise. is this for standard vt100/hyperterminal type terminal? is there an example of serial output available anywhere?
Title: Re: $20 LCR ESR Transistor checker project
Post by: kubi48 on January 11, 2014, 11:33:10 pm
You have always to program the flash memory with the .hex file and the EEprom with the .eep file for correct operation.
The serial output should be nearly the same as displayed on the LCD.
It is output with 9600 baud (1 Stop bit) with a 5V level.
The capacitor symbol is shown as -||- and the resistor symbol as -RR- .
The diode is shown as  ->|-  or  -|<-  .
The omega sign is replaced by Ohm and the µ sign is replaced by u .


 
Title: Re: $20 LCR ESR Transistor checker project
Post by: han on January 12, 2014, 12:16:23 am
i build with atmega 328, relay protection, USB supply,and internal voltage reference

i find the accuracy is depend on stability of the USB supply voltage (different USB power source different result)

i plan to use DC-DC converter from digikey.

whats the beter solution: ?

1. use 5V to 5V DC-DC converter
2. Use 5V to 9V DC-DC converter + 7805


 is there anyone that using dc-dc converter to supply the device?
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 12, 2014, 12:30:30 am
You have always to program the flash memory with the .hex file and the EEprom with the .eep file for correct operation.

thank you for that info. that may explain why same type chips operate differently. i will burn the ee file too next time. this is odd considering flashing new chips that have blank ee will not work.

im disappointed serial output is so complicated and dont work with standard terminal.

i will try to fix both problems when vacation is over and i can play with code and recompile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on January 12, 2014, 12:59:01 am
Quote
2) one that is boxed: http://www.ebay.com/itm/181109931348 (http://www.ebay.com/itm/181109931348)

I've got a couple of these. The display is backlit, and the AVR is a 168 (in a socket) and comes with 1.07k firmware. The ZIF is a nice touch!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2014, 03:24:42 pm
whats the beter solution: ?

1. use 5V to 5V DC-DC converter
2. Use 5V to 9V DC-DC converter + 7805

7805 or 78L05 aren't recommended. Please use a MCP1702 or something similar. Also add a proper ripple filter to the DC-DC converter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2014, 03:32:26 pm
thank you for that info. that may explain why same type chips operate differently. i will burn the ee file too next time. this is odd considering flashing new chips that have blank ee will not work.

Several strings, display characters, tables and adjustment data are stored in the EEPROM. No wonder you get strange display outputs ;-)

Quote
im disappointed serial output is so complicated and dont work with standard terminal.

There's an arduino version (http://www.pighixxx.com/lavori/ardutester/ (http://www.pighixxx.com/lavori/ardutester/)) supporting serial output and including a nice GUI tool.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 12, 2014, 06:02:13 pm
i may try that ardunio version someday but im not a big fan of the environment. i prefer winavr by itself because its more compact, flexible, and powerful. uses 1/10th of pc resources too. admittedly ardunio is more popular with better support for beginners but not for me.

anyway thanks to that last hint from you and kubi eveythings working great now. obviously all the extra characters and signals were simply 0xff bytes from blank eeprom.  i have two of these working now at less than $2 in parts including avr. accuracy and stability are excellent.

this is an incredible project and already dozens of local fellow students and friends are as excited as me. thanks markus for a wonderful design and generous help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 13, 2014, 11:50:14 am
this is an incredible project and already dozens of local fellow students and friends are as excited as me. thanks markus for a wonderful design and generous help.

Markus Frejek designed the tester. Karl-Heinz (kubi) has carried on with the developement and I (another Markus ;-) have joined in with an alternative firmware. And we're happy to hear that you like the project.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 13, 2014, 12:28:57 pm
aha... i didnt know kubi was karl. what a team. thanks to both of you for bringing me up to speed on importance of ee in that build. im guessing putting those strings in ee is to save flash for the 8k version?

ive already sorted out half the "mystery" components in my junk box. i see what my final requirements are now and adjusting the makefile should do it. a stripped down version for mega8 with no powerdown seems to be the best fit for a group of local engineering students that im setting this up for. unfortunately i wont have access to my main computer for a couple weeks.

do you know if there is a hex file for mega8 anywhere on the net? also can you tell me what a "tex" file is? im not linux and a lot of this is new to me.

edit: i know what "tex' is now. nothing to do with hex or largest state in usa. i was using wrong search terms before.

i could still use a link to hex file for mega8. nothing useful on google so far. if you or anybody could help it would be appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on January 13, 2014, 01:14:16 pm
this?
svn://mikrocontroller.net/transistortester/Software/trunk/mega8

Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 13, 2014, 02:01:58 pm
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega8/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega8/)

thanks. sorry but im not good with these code suppositories. with your hint and a little link fixup im there.

this is just the build i need because others im involved with already have m8 breakout boards and only need the 6 resistors and a button. when im back to my big pc i will play with the makefile to enable pullups so i dont have to put one on the sw or tie bat and ref hi. also disable timeout because these are powered off serial/usb dongle. maybe investigate strings in flash instead of ee option too if theres room.

anyway none of these are important atm. i put the button on reset instead of pd7 which works great. heres a couple screen shots. within a fraction of a percent of precision meter readings. and as seen some of my "mystery" to-92 are pnp and others nfet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on January 13, 2014, 07:32:44 pm
I've ordered one of these (http://www.ebay.com/itm/New-Transistor-Tester-Capacitor-ESR-Inductance-Resistor-LCR-Meter-NPN-PNP-MOSFET-/251334183807?pt=LH_DefaultDomain_0&hash=item3a84af4b7f) which is a little expensive but I like the zif connector approach.

I think this is going to use the atmega 328 but I may want to change resistors to better tolerances and/or improve the voltage reference.

Anyone already done this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: attila123 on January 13, 2014, 09:03:51 pm
Hi guys!

What are the opinions about this ESR meter? I would need it to repairing LCD monitors, power supplies, etc, so in-circuit testing would be useful.

http://www.ebay.com/itm/Inductor-capacitor-Tester-Milliohm-Meter-ESR-Meter-LC-Meter-/130888138780?pt=LH_DefaultDomain_0&hash=item1e798a801c (http://www.ebay.com/itm/Inductor-capacitor-Tester-Milliohm-Meter-ESR-Meter-LC-Meter-/130888138780?pt=LH_DefaultDomain_0&hash=item1e798a801c)

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: cellularmitosis on January 13, 2014, 10:59:14 pm
Gandalf, I just got that exact unit in, and then found this thread.  I'd be happy to join in your efforts towards improving this little unit!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on January 14, 2014, 12:10:33 pm
Atilla
These are all variations on a theme but I would beware of cheap Chinese copies.

Cellular
I'm mainly a hardware designer but can also do software - 60/40 is the split.  I like the utility of the meter just for having around my workshop evne if I do nothing to modify it.

I am interested in coming up with a revised set of hardware and letting someone else tweak the software - is that someone you I wonder?  Do you have any AVR studio skills?

Did you get schematics for yours or will we have to reverse engineer it - or more likely find out how close a clone it is of the original design?

I've read the whole thread and here's a summary (from memory) of things that can be improved:

1. The 2.5 volt reference voltage
2. Use 0.1% resistors where they matter
3. Put some thought into how best to lay out the component connection pads
4. Add an auto-discharge system (relay?) to discharge capacitors before testing

Stretch ideas:
a. Redesign the board to fit in a standard case
b. Add a frequency counter or does it already do this? - I have several iterations of a counter project that I did a while back using a PIC
c. Add a signal generator of some kind

Feel free anyone to chip in on this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2014, 01:26:02 pm
aha... i didnt know kubi was karl. what a team. thanks to both of you for bringing me up to speed on importance of ee in that build. im guessing putting those strings in ee is to save flash for the 8k version?

Exactly! Every byte counts ;-)

BTW, the 8k version has only a limited set of features and the 16k version has some limitations too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2014, 02:04:22 pm
I've read the whole thread and here's a summary (from memory) of things that can be improved:

1. The 2.5 volt reference voltage
2. Use 0.1% resistors where they matter
3. Put some thought into how best to lay out the component connection pads

Stretch ideas:
a. Redesign the board to fit in a standard case
b. Add a frequency counter - I have several iterations of a project that I did a while back using a PIC
c. Add a signal generator of some kind

The voltage reference helps if you got a poor voltage regulator. With a MCP1702 there's no need for it. Just the probe resistors should be 0.1% types. There are lots of PCB layouts in the support forum. Haven't looked into the possibility of a simple frequency counter yet (if it might be feasable with the standard pin assignment). The m-firmware includes a PWM tool (frequency is selectable from a menu and the ratio is adjustable in steps of 5%). For more information please see Karl-Heinz' excellent documentation (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/)).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on January 14, 2014, 02:24:09 pm
Madires
Thanks for the advice.  your link takes me to a page that appear to have pdf documents available but I can't seem to download or view them, do I need some special software?

When I eventually get the files, is there a source code file that I can compile in AVR studio or do I need another tool? 

Is the source in C or assembly or mixed?

Thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: cowana on January 14, 2014, 02:30:19 pm
To download those files, hit the "Download GNU tarball" link below the file names.

Andy
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2014, 02:48:38 pm
When I eventually get the files, is there a source code file that I can compile in AVR studio or do I need another tool? 

The current version is always available at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) and should compile in AVR studio.

Quote
Is the source in C or assembly or mixed?

Mostly C, but a few pieces are in asm.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on January 14, 2014, 07:19:22 pm
Thanks, got the files downloaded and into AVR Studio 6.  It seems to compile OK for the 328 version.

Don't have the kit from China, probably won't for 10 days or more.
Title: Re: $20 LCR ESR Transistor checker project
Post by: netdiver on January 14, 2014, 10:12:34 pm
Dear All,
first of all I would like to thank Markus and Karl-Heinz for being here and supporting. This project is really great! Thanks also to Markus Frejek who started this incredible little swisstool.

I'm totally new to the world of microcontrollers and I'm here after googling a bit about the Transistor Tester I bought on the bay.
After reading some times this thread, I decided that I should upgrade my new tester. Here it is:
(http://eev.eevblog.com/forum/index.php?action=dlattach;topic=14399.0;attach=76707;image)
I removed the zener D1 and soldered an ISP header (10 pin) to program it.
Being a complete newbie, I downloaded WinAVR and followed the direction given in the english documentation, and tried right away to put the 1.10k version on it, as it has only a Atmega168. I compiled the Makefile in the "default" directory, as it was designed for the 168.
But programming gave an error. After a little investigation, I found out that maybe the latest version does not fit anymore on a atmega168, as it is a bit larger than internal flash.
I succeded in installing 1.09k (i tried only the k versions, as the m version is only suitable for an atmega 328).
Is it true that from 1.10k on, Atmega168 will be insufficient to hold the newest versions of the firmware?

Another question: which flags on the Makefile of the default directory are suitable for this chinese clone? For this first flash, I left everything untouched, but I can't understand completely the meaning of the flags and put them in relation to the hardware.

I will try to solder the 100nF bypass caps where Karl-Heinz did, but... hey I need something very small to solder over these small atmega pins!

Thanks in advance.
Best Regards from Lorenzo
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 14, 2014, 10:31:43 pm
size is 17669 (0x4505) which is 1285 too much for m168. del a few features in the makefile and it will fit m168 or even m8.

i have a small problem myself. how do you run calibrate? whats really frustrating is it has been run twice before but im not sure how. shorting probes and hitting the button causes "not calibrated" message and instructions but then stops at  the site address. hitting the button during or after just starts that again.

the maunal and message says short probes and hit button and confirm within 2s but this dont work. what am i doing wrong?
Title: Re: $20 LCR ESR Transistor checker project
Post by: netdiver on January 14, 2014, 10:55:10 pm
Thanks very much paulie for your quick reply!
I commented out in the makefile the CFLAGS += -DWITH_UART an that did the trick! Now the code is at 99.3% and fits into the atmega 168!

As for your problem, I don't have this behaviour. Shorting the three test points together and pressing the test button I can see on the display "Selftest mode ?" If I press the test button again, the selftest / calibration starts. At a point it says "Isolate probe!": pulling out the short from the test points the calibration goes on, then the software asks for a capacitor greater than 100 nF and the selftest ends shortly after.

Thanks again for solving my issue!
Best regards
Lorenzo a.k.a. netdiver
Title: Re: $20 LCR ESR Transistor checker project
Post by: netdiver on January 14, 2014, 11:25:48 pm
A little step further... It's all in the documentation! So sorry for asking without having read thoroughly the docs.
I just noticed that to enable the extended test T1 to T7 it is necessary to disable one of the hFE measurement circuits.
I remove comment from NO_COMMON_COLLECTOR_HFE and now I have the T1 to T7 tests in the selftest mode, but I had to downgrade to 1.09k, as with 1.10k I'm not able to enable those extended tests without going over capacity of ATmega168.

Best regards.
netdiver
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 14, 2014, 11:46:36 pm
hmmmm... strange thing is it worked at one time. i cant compile atm but use the 1.10 hex file below that markus sent me.

when i reset or hit button i get "testing 1-rr-2-rr-3 00ohm 00ohm" and that damn warning. its very accurate and stable in test mode but cant get it to calibrate again. the only thing different is tying the zener pin high but that shouldnt matter.

Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on January 15, 2014, 12:45:33 am
problem solved.... reflashing all 3 chip made no difference but new eeprom upload fixed it. idk why that would make a difference but calibration is working ok now. looks like something was corrupted in the eeprom. maybe time to look at that bod fuse setting. i was at least able to suppress the warning in all of them by copying the ee data from the original but the defect got copied too. sorry for wasting everybodies time, all working great again.

i gotta say its astonishing how accurate this is. even without calibration they had less than 1% deviation but after less than 0.1% compared against thousand dollar precision meter. amazing, and all with less than a dollars worth of hardware. thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on January 15, 2014, 01:08:19 pm
Netdiver
To put caps on the power pins, you can scrape at the copper ground fill to expose bare copper, prep it with flux, and then put solder on it (you'll need a strong iron to heat the ground plane).  Then you can put one end of the cap on the Atmega pin and the other to the newly-created ground pad.

Can anyone point me to the absolute latest schematic for this project?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 15, 2014, 01:58:04 pm
Hi Lorenzo!

I removed the zener D1 and soldered an ISP header (10 pin) to program it.

That's the recommended procedure for the Chinese clones. Either remove the zener or replace it with a proper voltage reference.

Quote
I succeded in installing 1.09k (i tried only the k versions, as the m version is only suitable for an atmega 328).
Is it true that from 1.10k on, Atmega168 will be insufficient to hold the newest versions of the firmware?

The m-firmware supports the ATmega168 also. By setting the MCU to ATmega168 in the Makefile some features are disabled and the compiled firmware image will be small enough for 16kB flash and the smaller EEPROM. The k-firmware supports ATmegas down to 8kB flash with a limited set of features (read the documentation and edit the Makefile). If you like to have all available features you'll need an ATmega328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 15, 2014, 02:05:13 pm
Can anyone point me to the absolute latest schematic for this project?

The latest one is available at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/) (click "Download GNU tarball" at the bottom).
Title: Re: $20 LCR ESR Transistor checker project
Post by: netdiver on January 16, 2014, 02:29:08 pm
The m-firmware supports the ATmega168 also. By setting the MCU to ATmega168 in the Makefile some features are disabled and the compiled firmware image will be small enough for 16kB flash and the smaller EEPROM. The k-firmware supports ATmegas down to 8kB flash with a limited set of features (read the documentation and edit the Makefile). If you like to have all available features you'll need an ATmega328.

Thanks a lot Markus, so I can upload your firmware too!
Unfortunately my version has the SMD ATmega and my equipment lacks of SMD tools, so I'll stick with this version, until I find someone to sell it to!!

Thank you again for all your effort given in developing this project.

Lorenzo
Title: Re: $20 LCR ESR Transistor checker project
Post by: SteveM on January 21, 2014, 05:27:00 am
Hi, I am new to this forum but I did read this entire thread and I have learned a lot about this little device.  I noticed on ebay that the Chinese have put this tester into a new package with the brand name YIWANJIA.  There are three buttons to the right of the center off/on/test buttons, but they are labeled in Chinese and there is no English manual for this tester.  Does anyone know what those three new buttons do?
Title: Re: $20 LCR ESR Transistor checker project
Post by: SteveM on January 21, 2014, 08:59:03 am
Here are a couple of pictures to my post above to save the trouble of looking it up on ebay.  The specs seem to indicate it is the same circuit as the $20 LCR ESR transistor checker, but with updated software.


Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on January 21, 2014, 09:01:13 am
according to other pictures, one button is power, and other is test, as seen here: http://www.ebay.com/itm/181164691633 (http://www.ebay.com/itm/181164691633)
Title: Re: $20 LCR ESR Transistor checker project
Post by: SteveM on January 21, 2014, 09:52:16 am
That ebay seller messed up when attempting to label that picture.  The center button is actually two buttons.  The top half is on/test and the bottom half is off.  The three buttons to the right are something completely new.
Title: Re: $20 LCR ESR Transistor checker project
Post by: iloveelectronics on January 21, 2014, 10:51:07 am
They must be re-using a case with completely different purpose...

The sockets and buttons are labelled as "send message", "volume/lookup", "menu/confirm", "dial", "shortcut" etc. And the device is labelled "Chinese SMS Sender" or something. Completely unrelated to ESR  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rerouter on January 21, 2014, 10:55:40 am
Time to put my foot in with this project

Just bought one of these, (hope i picked correctly)
http://www.ebay.com.au/itm/200960094152?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 (http://www.ebay.com.au/itm/200960094152?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)

Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on January 21, 2014, 10:56:27 am
That ebay seller messed up when attempting to label that picture.  The center button is actually two buttons.  The top half is on/test and the bottom half is off.  The three buttons to the right are something completely new.

I thought those two buttons in the center would be for some paging in the display..
but the standard firmware is not supporting that type of screen ?, much bigger symbols, and also chinese text inside.
Title: Re: $20 LCR ESR Transistor checker project
Post by: SteveM on January 21, 2014, 11:12:56 am
Thank you all for the replies and thank you iloveelectronics for the translation.  That is very puzzling.  I would think it wouldn't take much to manufacture their own plastic box and label it correctly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2014, 01:41:23 pm
Just bought one of these, (hope i picked correctly)
http://www.ebay.com.au/itm/200960094152?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 (http://www.ebay.com.au/itm/200960094152?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)

It's one of the standard clones with an ATmega328. Might need an ISP header for firmware updates.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on January 22, 2014, 01:48:59 pm
It's one of the standard clones with an ATmega328. Might need an ISP header for firmware updates.

Have you seen those with the bigger screen, is that something that is supported in the firmware now?, or is that an custom chinese hack?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2014, 01:58:02 pm
I thought those two buttons in the center would be for some paging in the display..
but the standard firmware is not supporting that type of screen ?, much bigger symbols, and also chinese text inside.

It has to be a custom modification to support that LCD and include the extra symbols. Unfortunately the vendor doesn't seem to care about the project's Open Source Hardware nature.

BTW: A small Russian company will offer a transistortester clone with a nice enclosure (with pads for SMD, contacts for through-hole stuff and test clips) soon.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2014, 02:09:43 pm
Thank you all for the replies and thank you iloveelectronics for the translation.  That is very puzzling.  I would think it wouldn't take much to manufacture their own plastic box and label it correctly.

Could be less expensive than manufacturing new boxes. We don't know how much the vendor pays for those boxes and LCDs. But I don't recommend to buy any of those testers because they obviously don't run the "official" firmware. So you would be stuck with the firmware version installed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on January 22, 2014, 02:24:48 pm
I thought those two buttons in the center would be for some paging in the display..
but the standard firmware is not supporting that type of screen ?, much bigger symbols, and also chinese text inside.

It has to be a custom modification to support that LCD and include the extra symbols. Unfortunately the vendor doesn't seem to care about the project's Open Source Hardware nature.

BTW: A small Russian company will offer a transistortester clone with a nice enclosure (with pads for SMD, contacts for through-hole stuff and test clips) soon.

Cool, will that one also include programming headers/port etc?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2014, 02:48:31 pm
BTW: A small Russian company will offer a transistortester clone with a nice enclosure (with pads for SMD, contacts for through-hole stuff and test clips) soon.

Cool, will that one also include programming headers/port etc?

If I got that right it has a 10 pin ISP header (unpopulated).
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on January 28, 2014, 05:44:00 am
How long before it is being sold? Where will it be sold and for how much? What will it be able to do and how well? I need an esr meter.
 Thanks for any reply.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 28, 2014, 09:17:05 pm
How long before it is being sold? Where will it be sold and for how much? What will it be able to do and how well? I need an esr meter.

Got no idea about the date or price but they already offer ESR meters (http://www.radiodevices.ru/ (http://www.radiodevices.ru/)).
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on January 29, 2014, 05:05:28 am
OK Thanks for responding.
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on January 31, 2014, 12:09:44 pm
Mine has arrived.  Not done much with it yet but it works and appears reasonably accurate.

One aspect that's not as good as I thought is the ZIF socket.  It says 3M on it although it's probably a cheap Chinese copy; the issue is that it's about 5 mm from the top of the socket to where the actual connections start so testing a through-hole component that's been removed from a PCB would be almost impossible.  If I do a redesign, I'll go with the machined 0.1 pitch sockets + the SMT pads.
Title: Re: $20 LCR ESR Transistor checker project
Post by: J-D-H on February 18, 2014, 07:29:16 pm
I bought one of these tester via eBay, but the LCD display does not seem to have back-lighting.  The tester's main PC board is labeled "Ver 2.4 2013/07/01"; the PC board holding the LCD display is labeled "Zijing Electronics".  Pads 15 and 16 on the display PC board are unused (no pins attached), but these two solder pads do have traces connected to them (hard to trace the connections -- no schematic, solder mask, etc.).  Does anyone know whether back-lighting on this tester's LCD module can be enabled?  If so, how?  Also, would the 25-50mA or so for the back-light LEDs be too much for the 5V regulator?  Any help would be appreciated!

John
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rerouter on February 18, 2014, 07:49:17 pm
JHD, look between the LCD and its board, if there is a gap it has no back-light installed, if it has something white and about 1mm thick in the way it is installed but not powered,

now if its a generic LCD there is generally a set of jumpers on the back and pads for a dropping resistor to power the back-light off the VCC rail
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 18, 2014, 08:07:26 pm
I bought one of these tester via eBay, but the LCD display does not seem to have back-lighting.  The tester's main PC board is labeled "Ver 2.4 2013/07/01"; the PC board holding the LCD display is labeled "Zijing Electronics".  Pads 15 and 16 on the display PC board are unused (no pins attached), but these two solder pads do have traces connected to them (hard to trace the connections -- no schematic, solder mask, etc.).  Does anyone know whether back-lighting on this tester's LCD module can be enabled?  If so, how?  Also, would the 25-50mA or so for the back-light LEDs be too much for the 5V regulator?  Any help would be appreciated!

The first thing is to check if the LCD module has a backlight. Apply some mA to pads 15 and 16 and see if something happens. Use a PSU or a battery with a resistor to limit the current. The voltage regulator doesn't matter much. If it's able to provide enough current to power the backlight also you could simply add a resistor in series with the backlight. If not, build a small PWM backlight control with a current limiter, power the PWM by the 5V regulator and power the backlight by the battery directly (via a MOSFET with the current limiter). Or use some special LED driver (DC-DC converter, regulated by current).
Title: Re: $20 LCR ESR Transistor checker project
Post by: J-D-H on February 18, 2014, 09:42:11 pm
JHD, look between the LCD and its board, if there is a gap it has no back-light installed, if it has something white and about 1mm thick in the way it is installed but not powered,

now if its a generic LCD there is generally a set of jumpers on the back and pads for a dropping resistor to power the back-light off the VCC rail

Thanks for the quick and clear info!  I hoped the display might be internally edge lit, but if the BL function is always done with discrete LED(s), I'm out of luck -- mine has none visible.  I'm thinking of trying to tack a lead to the 5v switched voltage someplace and then using this to power a couple of flat style LEDs wedged under the LCD (shaving the LED thickness as needed).  Having a BL when the circuit is working sounds like a nice idea.  However given the fairly small A-hr capacity of 9V batteries, it might be best to just forget the whole idea.....
Title: Re: $20 LCR ESR Transistor checker project
Post by: J-D-H on February 18, 2014, 10:06:48 pm
The first thing is to check if the LCD module has a backlight. Apply some mA to pads 15 and 16 and see if something happens. Use a PSU or a battery with a resistor to limit the current. The voltage regulator doesn't matter much. If it's able to provide enough current to power the backlight also you could simply add a resistor in series with the backlight. If not, build a small PWM backlight control with a current limiter, power the PWM by the 5V regulator and power the backlight by the battery directly (via a MOSFET with the current limiter). Or use some special LED driver (DC-DC converter, regulated by current).

Thanks for your ideas!  If I understand correctly that back lighting of these LCD display modules is usually done via discrete LEDs, I see none behind mine.  I'll think about the idea of adding this function (as you suggested).  My first thought is to just use two LEDs in series via a simple dropping resistor to Vcc -- time for some experiments to see whether this sort of BL looks acceptable or not.....
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on February 19, 2014, 12:07:23 am
i can tell you none of the low cost ebay units have backlight. aside from cost issues the 9v battery life would be severely impacted. since i converted mine to 5vdc this was not an issue so swapping with a backlit unit was practical. trying to upgrade a non-lit one is not possible. theres more involved than just popping leds behind it. and why bother with lit units available for 2 bucks (shipped):

http://www.ebay.com/itm/LCD-Display-Character-Module-LCM-16x2-HD4478Controller-Blue-Blacklight-1602-TR-/181271994104?pt=LH_DefaultDomain_0&hash=item2a34a71ef8 (http://www.ebay.com/itm/LCD-Display-Character-Module-LCM-16x2-HD4478Controller-Blue-Blacklight-1602-TR-/181271994104?pt=LH_DefaultDomain_0&hash=item2a34a71ef8)

ill also mention asking the seller for details is another exercise in futility. mine swore it was backlit and used m328 not m8. both turned out not to be true. however for $10 i wasnt about to open a case. i will say the m8 version dont hold a candle up to the m328 hex file that markus posted here. no inductance, no calibration, etc and unbelievable spelling errors. since i built diy versions with serial io for less than a buck that work better i regret ordering that ebay one. live and learn.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rerouter on February 19, 2014, 01:31:53 am
a few pages back i posted a link to the one i purchased and it came with a back-light and the 328 mega in it, just missing an isp header,
Title: Re: $20 LCR ESR Transistor checker project
Post by: J-D-H on February 19, 2014, 04:20:44 pm
i can tell you none of the low cost ebay units have backlight. aside from cost issues the 9v battery life would be severely impacted. since i converted mine to 5vdc this was not an issue so swapping with a backlit unit was practical. trying to upgrade a non-lit one is not possible. theres more involved than just popping leds behind it. and why bother with lit units available for 2 bucks (shipped):

http://www.ebay.com/itm/LCD-Display-Character-Module-LCM-16x2-HD4478Controller-Blue-Blacklight-1602-TR-/181271994104?pt=LH_DefaultDomain_0&hash=item2a34a71ef8 (http://www.ebay.com/itm/LCD-Display-Character-Module-LCM-16x2-HD4478Controller-Blue-Blacklight-1602-TR-/181271994104?pt=LH_DefaultDomain_0&hash=item2a34a71ef8)

ill also mention asking the seller for details is another exercise in futility. mine swore it was backlit and used m328 not m8. both turned out not to be true. however for $10 i wasnt about to open a case. i will say the m8 version dont hold a candle up to the m328 hex file that markus posted here. no inductance, no calibration, etc and unbelievable spelling errors. since i built diy versions with serial io for less than a buck that work better i regret ordering that ebay one. live and learn.

On adding back lighting, a simple test with a light source held near the edge of the LCD module seems to indicate that adding a couple of small LEDs might do the trick.  But a new LCD module complete with BL would be easier -- thanks for the link!  Maybe I'll get one of these, but first I'm going to think over the topic of battery drain.  That, and make some measurements to see whether my tester board's pins 15 and 16 are actually connected to anything.  BTW, I did think about contacting the seller and asking about the BL, but guessing the result, I didn't try <g>.
Title: Re: $20 LCR ESR Transistor checker project
Post by: J-D-H on February 19, 2014, 04:32:03 pm
a few pages back i posted a link to the one i purchased and it came with a back-light and the 328 mega in it, just missing an isp header,

I'll look back and try to find the link.  Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on February 19, 2014, 07:02:42 pm
a few pages back i posted a link to the one i purchased and it came with a back-light and the 328 mega in it, just missing an isp header,

yes, the more costly ones do come with m328 and backlight as mentioned in the listings for those. unfortunately low cost units like mine ($10 bo, $15 bin) cut corners in both categories.  what annoyed me was the seller did not tell the truth about that. pretty good deal though considering and only took me a couple minutes to upgrade mcu and display.

and its true you can put leds behind a non lit unit but there are factors like diffuser and different polarizing screen that degrade visibility so much its not worth it. i should also mention that the yellow/green backlight appears much brighter than the blue ones. at least to my eyes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: linuxguru on February 21, 2014, 08:41:16 pm

yes, the more costly ones do come with m328 and backlight as mentioned in the listings for those. unfortunately low cost units like mine ($10 bo, $15 bin) cut corners in both categories. ... i should also mention that the yellow/green backlight appears much brighter than the blue ones. at least to my eyes.

The units with the M328, yellow/green backlight, and ZIF socket can be found at $20..$25, Buy-It-Now. They also have more capable firmware, including DF/Vloss measurement of capacitors, Depletion-Mode JFET measurements, etc.

The stock units with yellow backlight run the backlight and the red LED at very high currents - I changed two resistors on the board to cut the current by a factor of 10 or 20, and it's still bright enough for normal daytime use. Battery life improves enormously after this mod.

Edit: IIRC, I changed R9 and R14 to 10k to reduce the current drawn by the backlight and the red LED. Pic of modified unit shown (with the LCD panel detached to show the board). The two capacitors have been left untouched - mine came with Rubycon YXA at both locations.



Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on February 21, 2014, 10:41:15 pm
Just bought this:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on February 22, 2014, 12:03:10 am
Just bought this:
Could you have made a more smaller useless picture?

What is it? I would love to see, but... pixels...
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on February 22, 2014, 12:21:33 am
Just bought this:
Could you have made a more smaller useless picture?

What is it? I would love to see, but... pixels...

Let me dig a bigger one from the store.  My toy has not arrived.  The pitches of  3 bottom connector are just nice for the bigger MOSFET.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on February 22, 2014, 01:23:49 am
Looks like its this one http://www.ebay.com/itm/271367349891 (http://www.ebay.com/itm/271367349891)
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on February 22, 2014, 01:53:38 am
Looks like its this one http://www.ebay.com/itm/271367349891 (http://www.ebay.com/itm/271367349891)

Yes, same item.  I found some more interesting stuff from this store.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on February 22, 2014, 05:25:19 am
I was looking at that same one yesterday: Rechargeable Battery, test Zeners with up to 50V but why use the 168 and not the 328?
I don't think the shorting cap relay is implemented. It would be nice to see the PCB. What is the meaning of that 9V battery next to the unit?
Please post pictures once you get it.
Nice case :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 22, 2014, 01:18:40 pm
The units with the M328, yellow/green backlight, and ZIF socket can be found at $20..$25, Buy-It-Now. They also have more capable firmware, including DF/Vloss measurement of capacitors, Depletion-Mode JFET measurements, etc.

Don't worry about the firmware! Get the latest and greatest at http://www.mikrocontroller.net/svnbrowser/transistortester/Software (http://www.mikrocontroller.net/svnbrowser/transistortester/Software) ;-)
I commend to buy only clones with ATmega328 since new features and most improvements require >16kB flash. If you got an older/cheaper one with an ATmega168 it makes sense to replace it with an ATmega328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: obd.tech on February 22, 2014, 06:56:42 pm
i'm new to this gadget and forum https://www.eevblog.com/forum/Smileys/default/smiley.gif, (https://www.eevblog.com/forum/Smileys/default/smiley.gif,) is the newest firmware 1.09? i looked at the link above and got a little confused :-)
whats the 'Programm fuer Optionen WITH_SELFTEST und AUTO_CAL ueberarbeitet' all about?
Thanks
p.s. how do you put a smiley in the post text?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 22, 2014, 08:02:24 pm
i'm new to this gadget and forum is the newest firmware 1.09? i looked at the link above and got a little confused :-)
whats the 'Programm fuer Optionen WITH_SELFTEST und AUTO_CAL ueberarbeitet' all about?

The latest version (1.10k) is always in "trunk" and my alternative firmware (1.10m) in "markus". To download the directory click "Download GNU tarball".

Quote
p.s. how do you put a smiley in the post text?

This way: :) Just above the editor window you should see all emoticons. Click the one you like to add and it will be added at the cursor's position.
Title: Re: $20 LCR ESR Transistor checker project
Post by: obd.tech on February 23, 2014, 12:41:55 am
 Thanks for your help , i look forward to playing with my new toy and the things i hope to test & fix with the help and knowledge from this forum . Keep up the good work guy's https://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif (https://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif)

mmm......smileys don't work for me.....i clicked but nothing.....i can only drag one down.....then it comes out wrong :-(
What am i doing wrong?
Title: Re: $20 LCR ESR Transistor checker project
Post by: sleemanj on February 23, 2014, 01:18:59 am

It has to be a custom modification to support that LCD and include the extra symbols. Unfortunately the vendor doesn't seem to care about the project's Open Source Hardware nature.

FWIW, this appears to be the people who "developed" the large repurposed LCD version, fish8840 on Taobao.
http://item.taobao.com/item.htm?spm=a230r.1.14.35.QG5YBf&id=36323329572 (http://item.taobao.com/item.htm?spm=a230r.1.14.35.QG5YBf&id=36323329572)
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on February 28, 2014, 09:14:14 am
I was looking at that same one yesterday: Rechargeable Battery, test Zeners with up to 50V but why use the 168 and not the 328?
I don't think the shorting cap relay is implemented. It would be nice to see the PCB. What is the meaning of that 9V battery next to the unit?
Please post pictures once you get it.
Nice case :)

Fresh, not yet power up.  It is 328 uC.  But on the Taobao Chinese site, they said that it could range from 168 to 328.  As I mentioned on another post, those selling on ebay are normally trader and they could be carrying the old version.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Jerby on March 02, 2014, 05:40:42 pm
I build this tester and it works great. But it would be nice to have it on a PCB. Does anyone know if there are PCB's available, or batches to come?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Skimask on March 02, 2014, 05:45:39 pm
It's ~$20 on eBay.
Is your time worth that little?
Title: Re: $20 LCR ESR Transistor checker project
Post by: moemoe on March 02, 2014, 06:08:24 pm
I build this tester and it works great. But it would be nice to have it on a PCB. Does anyone know if there are PCB's available, or batches to come?

I created one (SMD), can be ordered eg via oshpark. https://github.com/maugsburger/avr-component-tester
Title: Re: $20 LCR ESR Transistor checker project
Post by: rr100 on March 04, 2014, 01:45:47 pm
Got the one from post #277, seems to do what it says on the tin, backlight display&all, micro on DIP socket. "not on" current really low like 0.02 microamps (but that's my last digit on my multimeter so don't trust it much except as ... really low). I don't think backlight will be much of a problem to the battery as it shuts down itself rather quickly (but still not annoyingly quick).
Title: Re: $20 LCR ESR Transistor checker project
Post by: guido on March 04, 2014, 10:22:38 pm
have the same one and made the following changes:

  - two SMD 47nF caps added to AVCC, DVCC to gnd (on the pins). Original cap removed
  - MC1403 2.5V reference added to pin27 (happened to have that one in the parts bin)
  - ic socket replaced with a good one
  - latest sw version

to do
 - change measurement resistors to 0.1% types (680/470k).
Title: Re: $20 LCR ESR Transistor checker project
Post by: rr100 on March 11, 2014, 11:26:57 am
Did not manage to break the ZIF socket yet (I don't think is particularly bad, probably it might break if you put something thicker and you try to close it but works.

On what I can double check it seems to get 2 significant digits (note: that's not the same as 1%!), all in all quite satisfied.
I think it wouldn't be hard to include some marginal input protection and the requiered analog stage to make it measure something like 0-100V at least and maybe one shunt just to have everything completed as a small multimeter (it can be made much compact if needed, mine is all through hole).

I would really use such a toy, sometimes you just need a multimeter but is not critical enough and is not ofthen enough and I can't justify the weight of a full unit (even a small one). I got to a point where I was checking batteries with a bus pirate (which I had with me because I needed now and then for the serial capabilities). This has everything it needs, including a display!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 11, 2014, 02:21:48 pm
On what I can double check it seems to get 2 significant digits (note: that's not the same as 1%!), all in all quite satisfied.
I think it wouldn't be hard to include some marginal input protection and the requiered analog stage to make it measure something like 0-100V at least and maybe one shunt just to have everything completed as a small multimeter (it can be made much compact if needed, mine is all through hole).

That's something we should consider for a future Tester+. The nice thing about the current design is that it is very simple and easy to build. The other important point is the firmware compatibility. The k-version supports several modifications meanwhile and it's quite hard to check all variations for each code change. Supporting several different hardware versions makes the firmware development much more complicated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 11, 2014, 02:38:02 pm
The new m-version 1.11m is released (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)). What's new?
- several minor improvements
- BJTs with base emitter resistor
- BJTs with freewheeling diode on the same substrate
- detection of (un)symmetrical drain and source for depletion mode FETs
- detection of body diode for depletion mode FETs
- improved pinout detection for Triacs (G, MT1 & MT2)
Title: Re: $20 LCR ESR Transistor checker project
Post by: SeanB on March 11, 2014, 03:05:26 pm
Got mine this week, and it is good enough to use for checking semiconductors, mid range capacitors and resistors. Going to keep it in my tool box for general quick testing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rr100 on March 11, 2014, 03:41:18 pm
Just bought one of these, (hope i picked correctly)
http://www.ebay.com.au/itm/200960094152?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 (http://www.ebay.com.au/itm/200960094152?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)

It's one of the standard clones with an ATmega328. Might need an ISP header for firmware updates.

Will probably upgrade the firmware every now and then, any advantage in adding the ISP header versus taking the micro out (is on a socket)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 11, 2014, 03:54:10 pm
Will probably upgrade the firmware every now and then, any advantage in adding the ISP header versus taking the micro out (is on a socket)?

Less mechanical stress. Choose whatever suits you better.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eevbstedt on March 16, 2014, 04:45:39 pm
Does anyone know where an English version of the 'changelog.txt' file located here?
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/)

Just picked up a newer version of the tester off ebay and am looking for firmware options.  I've attached a copy of the file for easier access.


Update:
I put the file through Google Translate and came up with this (I've cleaned it up a little).  Can you take a peek and give feedback?  Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 27, 2014, 06:11:45 pm
Does anyone know where an English version of the 'changelog.txt' file located here?

AFAIK Karl-Heinz doesn't provide an English version yet. The CHANGES file for the m-firmware is in English anyway ;-)

Quote
I put the file through Google Translate and came up with this (I've cleaned it up a little).  Can you take a peek and give feedback?  Thanks!

I think I'll suggest to Karl-Heinz to maintain an English version too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 27, 2014, 06:19:53 pm
Some news about current firmware changes. The trunk version of the k-firmware supports:
- in-circuit capacitance and ESR measurements
- frequency measurement (hardware option)
- squarewave signal generator
- PWM generator

The new m-firmware currently under development will include ESR and in-circuit ESR measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eevbstedt on March 27, 2014, 07:10:31 pm
Thanks for the info and update (as always)!

Did you have a chance to look over the translation?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 27, 2014, 09:58:31 pm
Did you have a chance to look over the translation?

Yep. Please don't be disappointed, it still needs some work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eevbstedt on March 27, 2014, 10:26:42 pm
Yep. Please don't be disappointed, it still needs some work.

On, not at all!  The only disappointment I have is in the lack of feedback.  Please feel free to offer suggestions/translations.  I'm looking forward to it!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 28, 2014, 09:57:07 am
On, not at all!  The only disappointment I have is in the lack of feedback.  Please feel free to offer suggestions/translations.  I'm looking forward to it!

I'll send you a private mail.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eevbstedt on March 28, 2014, 04:19:27 pm
Got it, thanks!  I'll re-up a new version of the file once I have a chance to chew-over all your edits.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on March 31, 2014, 03:11:46 pm
Some news about current firmware changes. The trunk version of the k-firmware supports:
- in-circuit capacitance and ESR measurements
- frequency measurement (hardware option)
- squarewave signal generator
- PWM generator

The new m-firmware currently under development will include ESR and in-circuit ESR measurements.

is there a hex file version available? english description of the freq counter anywhere?

nothing obvious at mikrocontroller.net site. i dont speak german and like many diy hobbyists not good with code suppositories.  i know links have been posted before but this thread is really big now and nothing in post #1 so if anyone has any handy it would save a half hour of searching. thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 31, 2014, 10:50:12 pm
Source and some HEX files for common setups are available at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) (click "Download GNU tarball"). Docs are at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/) (just ttester.pdf , but unfortunately you have to download the whole directory).
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on April 01, 2014, 12:00:47 am
thank you, i dont know why i have such trouble getting back to that link. its in my favorites but i have so many.... anyway i got "mega328" which i assume is most common. and this time i know what tarball is and that ee image is required. one question... i dont read german so what does "2uf-50mf" mean?

lol. just kidding! thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: quantumvolt on April 06, 2014, 05:37:55 am
I have seen this project for a long time, but until recently it never occured to me to look closer at it. But a few weeks ago I bought one of the eBay-clones. It turns out to be an almost unbelievable good instrument considering its simplicity and low cost.

I have - for a long time - been buying many different lots of the Russian 0.5% capacitors from eBay. As an example:

One of the lots I bought is (now) 18 pieces 0.0333 uF +- 0.5% - that is 33.3 nF nominal value. First I sorted them with a 6.5 digit DMM measuring the AC voltage across them when in series with a precision low tempco resistor and exposed to a sinus signal. Then I grouped them (by the last digit xx.xY nF) by using a DMM with capacitance meter. They all fell in bins from 33.26 to 33.45. This is spread of a bit less than 0.6%. I picked out the median bin (the spread of values was like a very flat bell curve - so I guessed that the mean and median value would be quite equal).

I then tested the 3 capacitors with median value in the tester. They all read 33.38 nF (which is appr. +0.24% relative nominal value 33.30 nF). This is probably too high value for the 3 center units in a lot of 18 units with +-0.5% tolerance.

Then I tested parallel and series combinations (all measurements repeated several times) and got very surprised:

All 3 units measure 33.38 nF

3 combinations of 2 units in parallel: 66.76-77
1 combination of 3 units in parallel: 100.2

3 combinations of 2 units in series: 16.69
1 combination of 3 units in series: 11.12-13

3 combinations of 1unit in parallel with [2 units in series]: 50.07
3 combinations of 1 unit in series with [2 units in parallel]: 22.25

All measurements agrees to within one count on the last digit with the formulas for capacitor combinations (around 0.1% or better linearity). There is no detectable offset in this tester/meter since this would have been disclosed for pure parallel (and series) combinations. There probably is a small gain error around +0.25% (appr. 33.38 divided by 33.30) - assuming that the median bin in close to nominal value 0.0333 uF. I have no way to check this unless I send the capacitors to someone with a meter that is 0.1% or better.

I thought I should fix up the meter (reference / pull up for "Vcc= ...", regulator, precision resistors, decoupling, tin the 3 measurement port traces etc.), but I won't touch it until I get the second one I have ordered now. That way I will know if I have been lucky or if I am tricking myself (no way ...)

Anyway - I have checked some 50 capacitors and inductors with tolerance 1% or less, and just in a few cases has the reading been out of spec'ed error.

An amazingly good little gadget.



Title: Re: $20 LCR ESR Transistor checker project
Post by: obd.tech on April 07, 2014, 12:50:39 am
Hi, newbies help please   ::)
How do i find out what firmware my new tool has (bought the one in the plastic case with the 328 chip) Is there a trick to finding a menu on the display for any different options? A simple new user guide would be good  :)
What are the recommended 'mods' apart from the resistor change to dim the lighting/power save?
keep up the good work  :clap: on this handy gadget (i just need to learn, how to use it now  :-\ )
Thanks to all  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 07, 2014, 02:00:53 pm
How do i find out what firmware my new tool has (bought the one in the plastic case with the 328 chip) Is there a trick to finding a menu on the display for any different options? A simple new user guide would be good  :)
What are the recommended 'mods' apart from the resistor change to dim the lighting/power save?

Based on the firmware version the version is displayed when powering up, down, or in the selftest mode. The older k-versions don't have a menu at all, but the latest k-version offers a menu for some extras (long key press). Please download the documentation of the last release at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/) (click "Download GNU tarball"). You'll find all mods in the documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on April 07, 2014, 02:10:18 pm
I downloaded that file now, and it's version 1.08k?, a file I downloaded somewhere in januar is version 1.10k?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 07, 2014, 02:37:53 pm
I downloaded that file now, and it's version 1.08k?, a file I downloaded somewhere in januar is version 1.10k?

1.10k is the version currently under development (source at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) und doc at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/)).

BTW: 1.12m (m-firmware) was released a few days ago. New features are ESR and ESR-in-circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on April 08, 2014, 01:21:07 am
Sorry But I am lost! Which one have all of you found is the best backlit one, and what do you have to do to make it  better? Is it set up to download the new file or do you just find the points and do it? Any videos of the process on this item.
Thanks for any help.
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 08, 2014, 12:32:19 pm
Sorry But I am lost! Which one have all of you found is the best backlit one, and what do you have to do to make it  better? Is it set up to download the new file or do you just find the points and do it? Any videos of the process on this item.

Of course it's the one I've built myself :-) It has got a PWM and a current limiter for the backlight (see the SVN for the schematic). Karl-Heinz' documentation has a section about the ebay clones, known hardware issues and how to fix them. Other possibilities for improvements are the hardware options like protection relay or high voltage Zener. The current method for updating firmware is ISP. So you will need an ISP programer (required anyway if you're playing with Atmel MCUs  ;-). BTW, you can use an Arduino as programer too. There aren't any how-to videos specificly for the TransistorTester, but if you search for "atmega ISP" you'll find tons of tutorials.
Title: Re: $20 LCR ESR Transistor checker project
Post by: fluxcapacitor on April 08, 2014, 01:05:46 pm
I downloaded that file now, and it's version 1.08k?, a file I downloaded somewhere in januar is version 1.10k?

1.10k is the version currently under development (source at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) und doc at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/)).

BTW: 1.12m (m-firmware) was released a few days ago. New features are ESR and ESR-in-circuit.

Great work madires, and karl-heinz. I`m interested in the in-circuit testing ,can anyone recommend which one to buy.Will any with the 328 do .
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 08, 2014, 01:24:57 pm
Great work madires, and karl-heinz. I`m interested in the in-circuit testing ,can anyone recommend which one to buy.Will any with the 328 do .

Thanks! Yes, any clone with an ATmega328 and a text based LCD will work fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on April 09, 2014, 01:21:40 am
Thanks Madires for responding. I will look at ebay and see if I can figure out which one to buy.
Thanks again.
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: jackryan315 on April 09, 2014, 08:15:13 am
My first post and hello to all. I have all the parts needed to make this ttester and i have a couple of questions:
1. is this the correct fuses for atmega328-pu with external 8 mhz crystal ( hfuse 0xd9, efuse 0xfc, lfuse 0xf7) (lockbit- 0xfc)
2. there is an svn link for m328, can i use that?
3. im going to use avrdudess gui for avrdude, are there any issues with it, like it wont work or something.?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 09, 2014, 09:24:32 am
My first post and hello to all. I have all the parts needed to make this ttester and i have a couple of questions:
1. is this the correct fuses for atmega328-pu with external 8 mhz crystal ( hfuse 0xd9, efuse 0xfc, lfuse 0xf7) (lockbit- 0xfc)
Yes!

Quote
2. there is an svn link for m328, can i use that?
That's http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/) (click "Download GNU tarball"). The hex file is for the flash and the eep file for the EEPROM. If you add any hardware option please download the source code (trunk = current version under development), edit the Makefile and compile the firmware yourself.

Quote
3. im going to use avrdudess gui for avrdude, are there any issues with it, like it wont work or something.?
Haven't tried avrdudess myself but I assume that it will do the job.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jackryan315 on April 09, 2014, 09:35:03 am
hey thanks madires for replying. im gonna try it out now. thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jackryan315 on April 11, 2014, 11:39:11 am
first thing first ok, im a newbie so please bear with me.

1. ive got an atmega328-pu with arduino bootloader.
2. im using avrdude with avrdudess as gui.

when i connected the chip with 8mhz crystal, avrdude cant' talk to the chip. but when i swapped it out with a 16mhz its recognized. i know that the bootloader is set with 16mhz, but how can i program it with 8 mhz as the code requires an 8 mhz crystal? any guidance is appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 11, 2014, 12:35:57 pm
1. ive got an atmega328-pu with arduino bootloader.
2. im using avrdude with avrdudess as gui.

when i connected the chip with 8mhz crystal, avrdude cant' talk to the chip. but when i swapped it out with a 16mhz its recognized. i know that the bootloader is set with 16mhz, but how can i program it with 8 mhz as the code requires an 8 mhz crystal? any guidance is appreciated.

Have you connected the ATmega to your PC via a serial interface directly or are you using an ISP programmer?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jackryan315 on April 11, 2014, 12:48:39 pm
thanks for responding madires.

 im using usbasp as an isp programmer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 11, 2014, 12:59:19 pm
thanks for responding madires.

 im using usbasp as an isp programmer.

Actually the crystal frequency and the bootloader shouldn't matter because the programmer will set the ATmega to ISP-mode. Have you connected a pull-up resistor to the reset pin? Please post the fuse bits if you're able to read them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jackryan315 on April 11, 2014, 01:19:02 pm
yes a 10k resistor is connected at pin 1 of the atmega328.
here's a screenshot of the gui:

(http://i59.tinypic.com/26284tf.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 11, 2014, 02:06:10 pm
yes a 10k resistor is connected at pin 1 of the atmega328.
here's a screenshot of the gui:

I can't see any obvious  issue. You could try changing the bit clock for the 8MHz crystal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jackryan315 on April 11, 2014, 10:09:11 pm
how do i go about changing the clock bit?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2014, 12:21:56 pm
how do i go about changing the clock bit?

The bit clock is the speed the programmer talks to the ATmega. Please see avrdudess in the progammer section, port, baud rate and then bit clock (-B). BTW, -B is the commandline option used for avrdude. You could try to lower the speed. The recommendation is that the ISP clock should not exceed 1/4 of the CPU clock.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jackryan315 on April 13, 2014, 11:32:53 am
Hey thanks madires for the guidance. I've managed to build the tester and its awesome.  Its 1.10 version. The different function is cool, again thanks a lot.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eevbstedt on April 13, 2014, 05:04:09 pm
I see that 1.10k has been moved (added) to the 'Tags' folder:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/?sortby=date (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/?sortby=date)

I'm assuming that this means 1.10k is 'done' and he's now working on 1.11k?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 13, 2014, 08:02:08 pm
I'm assuming that this means 1.10k is 'done' and he's now working on 1.11k?

That's right!
Title: Re: $20 LCR ESR Transistor checker project
Post by: eevbstedt on April 13, 2014, 08:25:53 pm
This is EXCITING!!!  ... or is it!?   Sooo mysterious!  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on April 17, 2014, 05:35:21 pm
On ebay it seems that there are three other variations that have been developed of this:
http://www.ebay.com/itm/171285924831 (http://www.ebay.com/itm/171285924831)

http://www.ebay.com/itm/181164691633 (http://www.ebay.com/itm/181164691633)

http://www.ebay.com/itm/201074091766 (http://www.ebay.com/itm/201074091766)

According to the description, it seems like it have to be the same, and same firmware, but with some modifications, too bad, as it doesnt seem like there are any upgrade options, or no firmware source available, because the hardware starts to look very interresting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on April 17, 2014, 05:49:33 pm
They look nice, but in fact they do not tell you more.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on April 17, 2014, 05:54:17 pm
I prefer this old design with HD44780 compatible LCD, because they are cheap, easy to buy, and they will be probably always available.
Title: Re: $20 LCR ESR Transistor checker project
Post by: g***! on April 17, 2014, 07:13:39 pm
I have the version, in the second picture in post 361....It arrived today. Its all SMD with an M328P and an unpopulated space for a 10 pin programming header.
Along the top edge of the board is another unpopulated space for a 16 pin header....interesting!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 17, 2014, 07:40:46 pm
I have the version, in the second picture in post 361....It arrived today. Its all SMD with an M328P and an unpopulated space for a 10 pin programming header.
Along the top edge of the board is another unpopulated space for a 16 pin header....interesting!

The 16 pin header might be for a HD44780 display. I don't recommend to buy the Transistor Testers with the graphics display because they require a modified firmware, i.e. you can't use the latest release from the official repo. You'll be reliant on someone in China updating the firmware and I doubt that the source is available publicly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on April 17, 2014, 08:08:39 pm
The 16 pin header might be for a HD44780 display. I don't recommend to buy the Transistor Testers with the graphics display because they require a modified firmware, i.e. you can't use the latest release from the official repo. You'll be reliant on someone in China updating the firmware and I doubt that the source is available publicly.

Good point
Title: Re: $20 LCR ESR Transistor checker project
Post by: dannyf on April 17, 2014, 08:27:34 pm
Quote
Good point

The code is fairly well packaged (all in lcd-routines.c/.h). So if you ever need to port it to a different display, you just need to implement your own lcd-routines.c/.h and recompile.

I did it with a nokia 7110 display - which looks to be similar to the graphics lcds shown earlier.
Title: Re: $20 LCR ESR Transistor checker project
Post by: at2marty on April 17, 2014, 08:58:53 pm
I've read quite a bit about this project and am in the early stages of adapting it with a few minor modifications.  For the most part, most of what I plan will remain the same, but I chose to use an ATMega1284p so that I could do a few other things with it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jackryan315 on April 18, 2014, 01:29:51 am
i've changed my firmware to version 1.7k coz i have no use of the other function just yet. but good to know that its there if ever you need them. BTW, anyone have a link to the writeup of these tester, all versions i mean? I only found two of these which are versions 96k and 107k.
Title: Re: $20 LCR ESR Transistor checker project
Post by: free_electron on April 18, 2014, 05:30:19 am
I was looking at these today. Found em on ebay and discovered they were based of the microcontroller.net project and also documented on eevblog.

I want to make a nice board for these, includong the booster for the zeners, the shorting relays to protect the inputs and the other options not commonly found in the wingpangpong versions.

The board must fit a nice handheld box with proper battery holders. I will use either 4 aa cells or go with a rechargeable lithium battery (usb) in which case i awant to add a usb uart.

Now, i do like the graphical display... Anyone has the code for that ? If not i will use the dogm series displays.

I am going to make a connector plate so ican push sot23, sot89 sot 232 and many other smd packages on it to find out what they are.

I will release artwork as public domain and have a bunch of em made by itead so they are cheap.

Anyone interested in the bare boards. For the cost of an envelope and international stamp....
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 18, 2014, 05:50:44 am
I've read quite a bit about this project and am in the early stages of adapting it with a few minor modifications.  For the most part, most of what I plan will remain the same, but I chose to use an ATMega1284p so that I could do a few other things with it.

Perfect timing :-) Karl-Heinz has started to work on an  ATmega324/644/1284 version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 18, 2014, 05:58:16 am
i've changed my firmware to version 1.7k coz i have no use of the other function just yet. but good to know that its there if ever you need them. BTW, anyone have a link to the writeup of these tester, all versions i mean? I only found two of these which are versions 96k and 107k.

You'll find the docs for the old firmware versions at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/old/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/old/english/) and the old firmwares at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/tags/). The current version under development is in the trunk directory and the m-firmware at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/). To download directories please click "Download GNU tarball" at the bottom.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 18, 2014, 06:03:29 am
I will release artwork as public domain and have a bunch of em made by itead so they are cheap.

If you like we could put it into the official repo (there's a hardware section already).
Title: Re: $20 LCR ESR Transistor checker project
Post by: SeanB on April 18, 2014, 08:41:15 am
I will nibble for a few boards, then build them up for the local HAM club. that should keep them busy ( and me as well) for a week or three building them. Will pull out the odd displays I have to use there as well.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dannyf on April 18, 2014, 09:50:05 am
an interesting twist would be to make an arduino-shield that has all the hardware other than the mcu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: at2marty on April 18, 2014, 10:15:28 am
I've read quite a bit about this project and am in the early stages of adapting it with a few minor modifications.  For the most part, most of what I plan will remain the same, but I chose to use an ATMega1284p so that I could do a few other things with it.

Perfect timing :-) Karl-Heinz has started to work on an  ATmega324/644/1284 version.

That's good to hear.  I would be more-than-willing to contribute in any way that I can.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on April 18, 2014, 10:17:01 am
an interesting twist would be to make an arduino-shield that has all the hardware other than the mcu.

Cannot find more about this project, seems like website is down:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-esr-lcr-transistor-npn-pnp-mosfet-meter/msg234473/#msg234473

Title: Re: $20 LCR ESR Transistor checker project
Post by: Flump on April 18, 2014, 10:32:35 am
I really want to get an esr meter that can test in circuit
and also a transistor tester/semiconductor tester

but there is so many versions of these now i dont know what to get lol
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 18, 2014, 12:23:39 pm
I really want to get an esr meter that can test in circuit
and also a transistor tester/semiconductor tester

The ESR in-circuit measurement was added in the firmware versions 1.10k and 1.12m . We (Karl-Heinz and myself) encourage everyone to give us feedback about the in-circuit ESR feature.

Quote
but there is so many versions of these now i dont know what to get lol

It's like standing in front of the shelves full of detergents in the super market :-) You can DIY or buy a clone. My recommendations are ATmega328 and a classic text based LCD module. Some clones come with a nice box but most lack the hardware options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Flump on April 18, 2014, 09:02:47 pm
Thanks for the advice madires :)

I would like to buy one I am not good enough with electronics yet to make one

which would you say was the best out of the all in one ebay modules ?
i have a limit of about £30
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 18, 2014, 09:46:30 pm
which would you say was the best out of the all in one ebay modules ?
i have a limit of about £30

There isn't any particular clone which is the best. Select the one which suits you most (test pads / textool socket / probe leads or whatever you prefer). Another thing to watch out for is the ISP header (unpopulated in most cases) for flashing new firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Towger on April 19, 2014, 08:21:56 am
Anyone interested in the bare boards. For the cost of an envelope and international stamp....
Yes, I am interested. I have been following this thread for ages now. The additional input protection along with the new support for in circuit ESR testing would make one very useful.
Are you going to design it through hole and/or SMT?
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on April 19, 2014, 09:45:26 am
Anyone interested in the bare boards. For the cost of an envelope and international stamp....

I'm intrested, too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BravoV on April 19, 2014, 09:47:21 am
Anyone interested in the bare boards. For the cost of an envelope and international stamp....

Vincent, I'm in, thanks !  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on April 19, 2014, 10:00:24 am
Anyone interested in the bare boards. For the cost of an envelope and international stamp....
Would be very interrested!
Will it use the 328 or an bigger mcu?, ref this:

I've read quite a bit about this project and am in the early stages of adapting it with a few minor modifications.  For the most part, most of what I plan will remain the same, but I chose to use an ATMega1284p so that I could do a few other things with it.

Perfect timing :-) Karl-Heinz has started to work on an  ATmega324/644/1284 version.

Title: Re: $20 LCR ESR Transistor checker project
Post by: apelly on April 19, 2014, 10:07:52 am
Anyone interested in the bare boards. For the cost of an envelope and international stamp....
Yes please! I was going to make one myself, but that will take ages considering the rate at which I'm currently getting things done.
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on April 19, 2014, 01:45:13 pm
I having wanting to build one of these also , but kinda waiting for one design settles , with some of the newer ideas coming on now , I just need to start ;)
So if you have room , put me on the list also ?
Thanks
John
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on April 20, 2014, 02:33:43 pm
I want to make a nice board for these.
Anyone interested in the bare boards. For the cost of an envelope and international stamp....
Count me in for a couple.

From what I have seen a larger memory, decent resistors, programming header, crystal, battery, external power, backlighting and zif socket are all highly desirable features. As Madires mentioned going with a non standard display can add complexity for no benefit.
I highly recommend going with the display I have pictured, not only are they cheap, easy to source and replace but they look great.

I think the zif socket outside the enclosure works well also like a eprom programmer. Then insert a small pcb into the zif socket for smd devices, or wires for probes etc. Here is my idea I was thinking of, being that you can easily detach the display and it doesn't interfere with the main board.
I was going to make a modular sub board with the zif socket but later decided mounting everything from the zif is better.

(http://i62.tinypic.com/2wfi88i.jpg)

(http://i42.tinypic.com/2eulyqg.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 20, 2014, 03:27:32 pm
From what I have seen a larger memory, decent resistors, programming header, crystal, battery, external power, backlighting and zif socket are all highly desirable features.

And a bunch of options:
- PWM backlight (just hardware)
- 2.5V voltage reference (if not using a MCP1702 or something similar as voltage regulator)
- protection relay (for discharging caps)
- high voltage Zeners (up to 50V DC, boost converter, requires 2 dedicated test pins)
- frequency counter (extra input)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fluxed Matter on April 21, 2014, 05:50:35 am

Anyone interested in the bare boards. For the cost of an envelope and international stamp....

How about local pickup? Or just drop it in the mail.


Sent from my iPhone using Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: jackryan315 on April 21, 2014, 10:45:57 am


Anyone interested in the bare boards. For the cost of an envelope and international stamp....

count me in for a board or two.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on April 22, 2014, 01:47:15 am
What is the cost of a board and shipping to San Bernardino. What would you think the total cost of a completed board would be? When would this happen and when would you have a picture of a completed board?
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fluxed Matter on April 22, 2014, 03:50:22 am
I think we should create a new thread about fe's new board so as not to derail this one.


Sent from my iPhone using Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: true on April 23, 2014, 02:33:47 am
Anyone interested in the bare boards. For the cost of an envelope and international stamp....
I'm just a state over :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 23, 2014, 09:40:49 am
Please use private mail for your "me too"!
Title: Re: $20 LCR ESR Transistor checker project
Post by: vindoline on April 25, 2014, 04:00:04 pm
Hi Madires,

I've finally gotten around to finishing up my version of this great "transistor tester" project. I've flashed your latest firmware (1.12m) and the hardware/software seem to be working fine! The only components that I feel I can measure with any real accuracy/precision are resistors. I used a series of 1% metal film resistors from 1R to 1M, measured them with 2 different Fluke DMM's and then the new "transistor tester" The unit is remarkably accurate and agrees with the Flukes between 10R and 1M. Below 10 ohms the unit reads 5-10% high.

My question is about the inductance measurement. For values of about 100 uH and below, the unit identifies the part as a low value resistor, not inductor. For higher value inductors, the measured value reads low (compared to the "nominal value" of the parts). I don't have another LCR meter to verify the actual inductance with, so the readings may actually be just fine. In any event, could you comment on the general measurement range and accuracy of the inductance measurement? Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on April 25, 2014, 04:15:22 pm
i am still amazed at the capabilities of this project. it is by far my most useful piece of test equipment. working with geiger counter designs it has proven a huge time saver checking hv transistors, hv caps, and inductors to see if they are still alive (usually NOT! lol).

even my cheap $1 harbor freight dvms do pretty good with semiconductors so one thing i would love to improve is ability to measure lower value inductance and caps. even if it involves some minor hardware changes. i plan to dig into that pdf to get more up to speed on the theory but could also use some hints as to current ranges and how to improve lower value measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dannyf on April 25, 2014, 05:15:29 pm
Quote
For values of about 100 uH and below, the unit identifies the part as a low value resistor, not inductor.

An inductor with infinite inductance is a resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 25, 2014, 05:45:43 pm
I used a series of 1% metal film resistors from 1R to 1M, measured them with 2 different Fluke DMM's and then the new "transistor tester" The unit is remarkably accurate and agrees with the Flukes between 10R and 1M. Below 10 ohms the unit reads 5-10% high.

That make sense since an additional measurement method is used for resistors less than 10 Ohms. Does anyone else also got those high values for resistors < 10 Ohms? I'm testing the firmware with 3-4 different testers to detect any issues, but sometimes there are still some surprises.

Quote
My question is about the inductance measurement. For values of about 100 uH and below, the unit identifies the part as a low value resistor, not inductor. For higher value inductors, the measured value reads low (compared to the "nominal value" of the parts). I don't have another LCR meter to verify the actual inductance with, so the readings may actually be just fine. In any event, could you comment on the general measurement range and accuracy of the inductance measurement? Thanks!

The inductance measurement is quite limited by the maximum test current and the method used. It even runs the ATmega out-of-spec for some µs for low inductances. The supported range is roughly 100µH up to 1H and the resistance has to be less than 2kOhms. With a clock rate of 16MHz you'll get a small improvement (factor 2). Therefore the inductance measurement is just for checking the order of magnitude and not for measuring the exact value. Any LCR meter will give you more precise results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 25, 2014, 05:58:20 pm
even my cheap $1 harbor freight dvms do pretty good with semiconductors so one thing i would love to improve is ability to measure lower value inductance and caps. even if it involves some minor hardware changes. i plan to dig into that pdf to get more up to speed on the theory but could also use some hints as to current ranges and how to improve lower value measurements.

The k-firmware goes down to 30pF and the m-firmware down to 5pF. With the current hardware design and the implied measurement methods low value measurements aren't really feasable. The oscillator method (frequency counter) or the AC generator method (U and I) are suited much better for that purpose. That's something for a Tester+ ;-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vindoline on April 25, 2014, 06:37:41 pm
Madires, Thank you very much for the reply! It looks like my inductor measurement are right in spec then! The capacitor measurements I've made seem pretty accurate, certainly in the ballpark for the nominal value. The next thing I'll try are some transistors, FETs, etc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: quantumvolt on April 25, 2014, 07:25:47 pm
An inductor with infinite inductance is a resistor.

Since you have (absolute values) V/I = 2*PI*f*L wouldn't you say that - for frequency f greater than zero - an infinite L is an infinite effective impedance V/I - that is to say an open circuit (albeit with a 90 deg phase shift). For steady state DC, any inductor - infinitesimal or infinite - would (as I read it) behave as a zero effective impedance - a short.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on April 25, 2014, 11:06:07 pm
The k-firmware goes down to 30pF and the m-firmware down to 5pF. With the current hardware design and the implied measurement methods low value measurements aren't really feasable. The oscillator method (frequency counter) or the AC generator method (U and I) are suited much better for that purpose. That's something for a Tester+ ;-)

yes, ive had good luck with "subtract 30pf" method but also working with uhf etc circuits it would be nice to get down in the range of 1 or 2 pf. the mid price meters do that w/o too much trouble so i guess low value inductors are the most desirable feature for me atm. since theres frequency counter function then maybe a simple inverter with switchable caps would do the trick. then its only a matter of some simple conversions. looks like its time to dig into the source.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dannyf on April 26, 2014, 12:01:40 am
Quote
For steady state DC, any inductor - infinitesimal or infinite - would (as I read it) behave as a zero effective impedance - a short.

And what's left is the serial resistance of an inductor.

So an inductor with infinite inductance will block any ac signal and let pass it the dc portion of the incoming signal.

Like a capacitor, in the opposite way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on April 26, 2014, 05:54:06 pm
I got one of these board from eBay for $20. It's amazingly useful--I primarily use it to identify transistors and verify the pinout.  I've run some tests on it for various values resistors, capacitors, inductors and voltage drop across some diodes. Attached are the results compared to a Fluke 187 multimeter, Brymen BM869 multimeter, and DE5000 LCR meter. The highlighted green columns are the "reference" columns that other values are being compared to.

* My board is marked as v 2.4 and is stock / as delivered with the Atmega168. It is running the 1.05k software.
* Transistortester resistance readings are within about 1% from 100 ohms - 1 Mohm. Low values have higher error. It doesn't look like it reads < .7 Ohms.
* Capacitance readings were generally close to the multimeter readings, but the DE5000 generally read much lower than the other meters
* Inductance couldn't be measured for the .8 - 1.6 uH inductors --it shows .7 Ohm resistance. Values for 10-
* Diode voltage drops read higher than the multimeters, but the Transistortester was able to produce a value while the multimeters could not

Testing notes:
* Capacitor readings were done at 1kHz on the DE5000 up to 100 uF and 100Hz for 2200 and 6800 uf Capacitors
* Red Led had a measured drop of 1.77V with 1mA, 2V with 20mA
* White led had a measured drop of 2.69V with 1mA and 3.27V with 20mA

I plan on updating the firmware when I get a programmer and possibly doing some of the hardware mods as previously suggested.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 26, 2014, 06:13:42 pm
* My board is marked as v 2.4 and is stock / as delivered. It is running the 1.05k software.
* Transistortester resistance readings are within about 1% from 100 ohms - 1 Mohm. Low values have higher error. It doesn't look like it reads < .7 Ohms.

Please update to 1.10k (1.05k is about 15 months old). That version measures low value resistors down to 0.01 Ohms.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on April 27, 2014, 02:24:44 am
I have revision 2.2 of that board and comes with the 8MHz crystal. Too bad they removed it from newer revisions. Mine is bricked after I tried to update the firmware.  I tried using the MiniPro TL866A and the USBAsp but fails. I don't know if the processor is cooked or something with the fuses. I have some Atmega328P-AU to replace the Atmega168. My USBAsp has the warning: cannot set sck period. please check for usbasp firmware update problem so I'm trying to breadboard another USBAsp to program the original one. I feel that for every problem I fix I get two new ones :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: gtroc71 on April 27, 2014, 03:00:41 am
I have revision 2.2 of that board and comes with the 8MHz crystal. Too bad they removed it from newer revisions. Mine is bricked after I tried to update the firmware.  I tried using the MiniPro TL866A and the USBAsp but fails. I don't know if the processor is cooked or something with the fuses. I have some Atmega328P-AU to replace the Atmega168. My USBAsp has the warning: cannot set sck period. please check for usbasp firmware update problem so I'm trying to breadboard another USBAsp to program the original one. I feel that for every problem I fix I get two new ones :(


Hey mate I had the same sck period problem but the info at http://www.rogerclark.net/?p=702 (http://www.rogerclark.net/?p=702) worked for me if you have an arduino handy.
Best of luck!
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on April 27, 2014, 06:38:09 am
No Arduino here, that's why I have to create a basic Arduino or a basic USBAsp to fix mine.
http://www.fischl.de/usbasp/ (http://www.fischl.de/usbasp/)
http://blog.apexelectrix.com/how-to-update-usbasp-firmwares/ (http://blog.apexelectrix.com/how-to-update-usbasp-firmwares/)
I have seen the solutions using the Arduino.
Now is breadboard time.
Thank you :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on April 27, 2014, 12:29:02 pm
that warning should be ignored. it has no effect on operation. its amazing how many have bricked their boards AND usbasp programmer thinking they had to update firmware. "if it aint broke dont fix it", even if you think it is because of that stupid message.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on April 27, 2014, 01:01:22 pm
* My board is marked as v 2.4 and is stock / as delivered. It is running the 1.05k software.
* Transistortester resistance readings are within about 1% from 100 ohms - 1 Mohm. Low values have higher error. It doesn't look like it reads < .7 Ohms.

Please update to 1.10k (1.05k is about 15 months old). That version measures low value resistors down to 0.01 Ohms.

Is there a place to submit features request?  I have a french made transistor tester, but the software has not been updated.  They do have a function to test opto-coupler.   On powerup, it shall detect if the opto-adapter is attached and so shall "mode" opto coupler testing.  Giving the CTR value accordingly.  Also is it possile to test MOSFET or IGBT driver chip, and those that are opto-isolated driver?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 27, 2014, 04:51:49 pm
Is there a place to submit features request?  I have a french made transistor tester, but the software has not been updated.  They do have a function to test opto-coupler.   On powerup, it shall detect if the opto-adapter is attached and so shall "mode" opto coupler testing.  Giving the CTR value accordingly.  Also is it possile to test MOSFET or IGBT driver chip, and those that are opto-isolated driver?

We're limited to three probe leads and a maximum voltage of 5V. For the autodetection of an opto-coupler we would need 4 probes. The MOSFET/IGBT drivers create voltages around 10V which are too high for the ATmega. At the moment I don't see any way to add the features above. If you got an idea please let me know.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on April 27, 2014, 05:18:54 pm
I put my AVR tester into a metal housing and I am getting wrong measured values of capacitors. What to do with that? Maybe a plastic housing would be better?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 27, 2014, 05:41:49 pm
I put my AVR tester into a metal housing and I am getting wrong measured values of capacitors. What to do with that? Maybe a plastic housing would be better?

Just for values in the pF range or also for µF? How much are the values off? Have you connected the metal case to the tester's ground or is the tester completely isolated?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on April 27, 2014, 06:12:36 pm
Just for values in the pF range or also for µF? How much are the values off?
I am getting some 50µF to 300µF readouts with test wires not connected to anything or sometimes when connected to a 300nF capacitor.
Have you connected the metal case to the tester's ground or is the tester completely isolated?
Yes, the metal case is connected to the tester's ground.
Well, this is strange. The fault appears only when simple non-switched PSU is used. When I use an industrial switched PSU, the problem never appears.
Semiconductor measurement is always correct.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 27, 2014, 06:49:55 pm
Yes, the metal case is connected to the tester's ground.
Well, this is strange. The fault appears only when simple non-switched PSU is used. When I use an industrial switched PSU, the problem never appears.

Could you please remove the connection between the metal case and ground and check again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on April 27, 2014, 06:53:11 pm
I will try it later...
Title: Re: $20 LCR ESR Transistor checker project
Post by: intrax on April 29, 2014, 02:08:40 pm
Hi guys,

I'm currently looking at : http://pages.ebay.com/link/?nav=item.view&id=171313859915 (http://pages.ebay.com/link/?nav=item.view&id=171313859915)
Is it any good and is the software upgradeable?
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on April 29, 2014, 02:37:24 pm
as mentioned the ones with graphic lcd will never be up to date with latest firmware. and dont really show more info. i also have a feeling it will be more than $11 before bidding ends. there are many out there easily impressed by bling.
Title: Re: $20 LCR ESR Transistor checker project
Post by: intrax on April 29, 2014, 03:43:21 pm
as mentioned the ones with graphic lcd will never be up to date with latest firmware. and dont really show more info. i also have a feeling it will be more than $11 before bidding ends. there are many out there easily impressed by bling.
Thanks your reply. Maybe it's better to wait for free-electron's board (whenever that may appear?) or look for an atmega328 with a character display as has been stated earlier in this thread.
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on April 29, 2014, 06:30:09 pm
personally i think its wise to stick with something compatible with original hardware. extra stuff dont hurt but its nice to take advantage of any innovatios cooked up by m and k. ie the recently added frequency counter which has just proven invaluable to me for measuring ultra low value caps and inductors (i did have to add an mb506 and 4040).

and if you are diy type dont forget you can throw together a quickie for less than $1 in parts:

Title: Re: $20 LCR ESR Transistor checker project
Post by: ecat on April 30, 2014, 11:33:37 am
Moving away from the $1 range, I have a couple of MCP3424s (4 ch, 18bit ADCs + Vref) sitting here looking for a home. Do you think there would there be any benefit swapping one in place of the internal ADCs and changing the code to accommodate of course  :)

MCP3424 http://ww1.microchip.com/downloads/en/DeviceDoc/22088b.pdf (http://ww1.microchip.com/downloads/en/DeviceDoc/22088b.pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 30, 2014, 12:48:54 pm
Moving away from the $1 range, I have a couple of MCP3424s (4 ch, 18bit ADCs + Vref) sitting here looking for a home. Do you think there would there be any benefit swapping one in place of the internal ADCs and changing the code to accommodate of course  :)

For some measurements an 18 bit resolution would be nice but the MCP3424 has some issues. It's really slow at 18 bits and can only use the internal 2.048V voltage reference. Therefore it would be only usable for high resolution measurments if the voltage is below 2V and if there are no timing constraints. The tester uses also the ATmega's analog comparator feature (taking the ADC pins as inputs for the comparator) and the ESR measurement performs exact timing of the internal ADC's S&H. You could add the external ADC in parallel and use it for more precise low voltage measurements, e.g. for resistors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ecat on April 30, 2014, 01:01:38 pm
Moving away from the $1 range, I have a couple of MCP3424s (4 ch, 18bit ADCs + Vref) sitting here looking for a home. Do you think there would there be any benefit swapping one in place of the internal ADCs and changing the code to accommodate of course  :)

For some measurements an 18 bit resolution would be nice but the MCP3424 has some issues. It's really slow at 18 bits and can only use the internal 2.048V voltage reference. Therefore it would be only usable for high resolution measurments if the voltage is below 2V and if there are no timing constraints. The tester uses also the ATmega's analog comparator feature (taking the ADC pins as inputs for the comparator) and the ESR measurement performs exact timing of the internal ADC's S&H. You could add the external ADC in parallel and use it for more precise low voltage measurements, e.g. for resistors.

Thanks for the info. Sounds like more trouble than it's worth with the MCP3424.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on May 01, 2014, 02:19:11 pm
Yes, the metal case is connected to the tester's ground.
Well, this is strange. The fault appears only when simple non-switched PSU is used. When I use an industrial switched PSU, the problem never appears.

Could you please remove the connection between the metal case and ground and check again.

So guys, there is no problem with the metal housing. The odd readouts are caused by some interference with the 230V power supply. The problem appears less if you use a switched power supply. The AVR tester's metal case should be connected to negative pole and you can put your hand on it to ground yourself, then it will be fine.


Title: Re: $20 LCR ESR Transistor checker project
Post by: intrax on May 05, 2014, 12:41:49 pm
What about free-electron's board as mentioned in this thread… Will it ever appear? If not I will go with one of the newer at328 boards from our chinese 'friends'.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on May 05, 2014, 06:30:00 pm
What about free-electron's board as mentioned in this thread… Will it ever appear? If not I will go with one of the newer at328 boards from our chinese 'friends'.

Well most of us own at least one so I doubt anyone is in too much of a hurry.
But a nice upgradable board design that offers all the features would be nice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: intrax on May 09, 2014, 11:48:37 am
Could someone tell me what board this esr meter is based upon: http://m.youtube.com/watch?v=WjkYq4Auvk8 (http://m.youtube.com/watch?v=WjkYq4Auvk8) and where to look for the layout?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on May 09, 2014, 02:38:24 pm
The Karl Heinz Kubbeler version is IMHO better.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on May 09, 2014, 06:14:31 pm
Intrax,
http://www.mikrocontroller.net/articles/AVR_Transistortester (http://www.mikrocontroller.net/articles/AVR_Transistortester)
It is in german, just let google translate it for you :)
All the information you need is there.
Title: Re: $20 LCR ESR Transistor checker project
Post by: simonmc on May 10, 2014, 09:49:36 am
I received my version yesterday, i will post some pics but i will have to resize them.

 It has a 168 installed and is running v1.07 i believe. I have to say i'm very impressed and the unit will prove very useful to me. I did have some problems with my order, it seems the first one the seller sent, got lost and the seller posted out a second one to me. I don't know if the one that has just arrived is the first or second one though so i may end up with another one in the next couple of weeks!

I will replace the 168 with a 328 when i get the time and replace the reg and resistors with better items and add some better decoupling to the micro. The fitted zener seems to be a smt 4.3V one. Can anyone recommend a decent LDO with the same footprint as the mounted 7805?

The ZIF socket is not the best quality but it is usable and if it breaks i will replace with a 3M one. I de-soldered the LCD and added a socket so that it is removable. I also added some stand off's to act as feet. I still have to add the 6 pin ISP header.

As regards to the latest firmware, can you good people confirm i have the correct tool chain to compile and programme the device. I have Amtel studio 6.1 installed, extreme burner AVR, and will be ordering a couple of the cheap ebay USB ISP devices that are on ebay. Is this all i need?

EDIT:- Added pics
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 10, 2014, 10:26:04 am
I will replace the 168 with a 328 when i get the time and replace the reg and resistors with better items and add some better decoupling to the micro. The fitted zener seems to be a smt 4.3V one. Can anyone recommend a decent LDO with the same footprint as the mounted 7805?

A zener? If a standard zener is connected to PC4 please remove it. And in case you like to have a voltage reference replace the zener with a LM285 or LM4040 2.5V. I'd recommend to use the MCP1702 as LDO, even with the different pinout. It works great and you don't need the external voltage reference.

Quote
As regards to the latest firmware, can you good people confirm i have the correct tool chain to compile and programme the device. I have Amtel studio 6.1 installed, extreme burner AVR, and will be ordering a couple of the cheap ebay USB ISP devices that are on ebay. Is this all i need?

Atmel Studio is fine. Can't say anything about extreme burner AVR since i'm using avrdude. And for the programmer I'd get something like the Diamex ALL-AVR which does ISP, PDI and TPI (USB is compatible with AVRISP-MkII).
Title: Re: $20 LCR ESR Transistor checker project
Post by: simonmc on May 10, 2014, 11:39:22 am
Quote
A zener? If a standard zener is connected to PC4 please remove it. And in case you like to have a voltage reference replace the zener with a LM285 or LM4040 2.5V. I'd recommend to use the MCP1702 as LDO, even with the different pinout. It works great and you don't need the external voltage reference.

It looks like a zener judging by its code (431, mounted just above and to the right of the micro in the second pic i posted) and is connected to PC4. Should i remove that part even though i dont have a reference or ldo on hand till i get to work?? Does this zener actually decrease the accuracy of the cct or does it do nothing at all?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 10, 2014, 01:21:05 pm
It looks like a zener judging by its code (431, mounted just above and to the right of the micro in the second pic i posted) and is connected to PC4. Should i remove that part even though i dont have a reference or ldo on hand till i get to work?? Does this zener actually decrease the accuracy of the cct or does it do nothing at all?

Hmm, could be a TL431. Are two pins shorted (cathode and ref)? A TL431 should be fine too. Though, we don't know it's accuracy (AFAIK you can get 2%, 1% and 0.5% types). It's all about the ADC's voltage reference. Either you got an accurate and stable 5V regulator or a proper external voltage reference. In the first case the tester assumes that 5V are 5.000V. In the latter case the tester uses the external voltage reference to calculate the offset of the 5V rail. For a 7805/78L05 you'll need the external voltage reference because the 78 is not accurate enough. The MCP1702 LDO for example has an accuracy of 0.4%. An external voltage reference with a poor accuracy will make the tester less accurate.
Title: Re: $20 LCR ESR Transistor checker project
Post by: simonmc on May 10, 2014, 02:15:46 pm
looking at the datasheet it could very well be a TL431. Yes the cathode and ref pins are shorted.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aragorn on May 17, 2014, 12:05:52 am
Is there a file download section here for the tester Pcb layouts? I just built the tester, would like to cleanup the project. Is anyone selling blank pcbs?

Thanks,
-d
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on May 17, 2014, 01:42:05 am
Aragonrn,
There are many different versions of the tester as is discussed here:
http://www.mikrocontroller.net/articles/AVR_Transistortester (http://www.mikrocontroller.net/articles/AVR_Transistortester)
All the information can be found there.
Assembled and ready to go testers can be found on ebayy for as little as $13
There is a member of the eevblog that might make a board soon.
If you have questions after reading all the info available here and the site mentioned above, please come back and ask. :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: Aragorn on May 19, 2014, 01:19:59 pm
Thank you, just ordered 2 from China. Not exactly what I wanted, but for the price, I couldn't build one myself.

-d
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on May 28, 2014, 12:00:46 am
Well I bought this one 4 days ago from Hong Kong and it arrived today, that's a record for me as normally Asian E-bay shipping to me on West Coast USA is 10-12 days.

 It's got the 328P avr chip in a socket. No ISP connector. I put a couple of npn, pnp, caps and it identified them all. Then I dug out my 250 .01% reference resistor and it read it as 249.5 so I'm pretty impressed.

I added four 1/2" nylon standoffs so it would sit flat and wrapped the 9 volt battery in plastic tape and rubber banded it to the back of the PCB. Who needs a case, not me.  ;)

http://www.ebay.com/itm/291041497713?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 (http://www.ebay.com/itm/291041497713?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)
Title: Re: $20 LCR ESR Transistor checker project
Post by: AintBigAintClever on May 31, 2014, 10:40:33 am
If you want the latest manuals go to http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/) and download the tarball (I've not found a way of viewing the PDFs within the browser, this seems to be the quickest way). German and Russian manuals are available if you go up to the parent folder.

Well worth it if you think this is just a component tester. Extra goodies are a few button presses away :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: Mr Smiley on May 31, 2014, 08:27:29 pm
Hi all,

Which version does the high 20,000uF capacitor readings as stated by the below ebay listing

http://www.ebay.co.uk/itm/New-Transistor-Tester-Capacitor-ESR-Inductance-Resistor-Meter-NPN-PNP-Mosfet-/251210970850?pt=LH_DefaultDomain_0&hash=item3a7d5736e2 (http://www.ebay.co.uk/itm/New-Transistor-Tester-Capacitor-ESR-Inductance-Resistor-Meter-NPN-PNP-Mosfet-/251210970850?pt=LH_DefaultDomain_0&hash=item3a7d5736e2)

Many thanks

 :)

Also, could this version be upgraded to the latest version just by upgrading the processor  :-+ :--

http://www.ebay.co.uk/itm/NEW-TRANSISTOR-TESTER-NPN-PNP-MOSFET-THYRISTOR-DIODE-RESISTOR-CAPACITOR-METER-/261192428249?pt=LH_DefaultDomain_0&hash=item3cd0482ad9 (http://www.ebay.co.uk/itm/NEW-TRANSISTOR-TESTER-NPN-PNP-MOSFET-THYRISTOR-DIODE-RESISTOR-CAPACITOR-METER-/261192428249?pt=LH_DefaultDomain_0&hash=item3cd0482ad9)

as it only costs 12 dollars and has a socketed processor


 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 31, 2014, 09:07:50 pm
Which version does the high 20,000uF capacitor readings as stated by the below ebay listing

Basically all do (theoretically up to 100mF).

Quote
Also, could this version be upgraded to the latest version just by upgrading the processor  :-+ :--

Any clone can be updated to the latest firmware, but only the ATmega328 can run the firmware with all features enabled. The other ATmegas with less flash memory got a stripped down firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mr Smiley on May 31, 2014, 09:24:22 pm
Hi,

Thanks, what gets me unsure sometimes is when China/Hong Kong put mF instead of uF  :-/O

The first ebay copies state upto 20,000uF and others, the latest version say 100mF ( mili or micro  |O )

So in the last link a posted, upping the atmega8 to a atmega328 will give it all for £7 uk pounds plus a 328  :-+ :--

 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on May 31, 2014, 09:32:07 pm
If you want the latest manuals go to http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/) and download the tarball (I've not found a way of viewing the PDFs within the browser, this seems to be the quickest way). German and Russian manuals are available if you go up to the parent folder.

Well worth it if you think this is just a component tester. Extra goodies are a few button presses away :)

Is it possible someone could simple post the english PDF manual or a direct link to the same? I don't seen to have a tarball compatible program to process that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mr Smiley on May 31, 2014, 09:46:07 pm
Hi,

The file is 1.5Mb, the file you want is 1.3Mb, but the limitation here is 1Mb.

7zip will open the file for you but you need two steps


1/ right-click on the example.tar.gz file and choose 7-Zip --> Extract Here from the context menu.
   
2/  then take the resulting example.tar file and the right-click again and choose 7-Zip --> Extract Here from the context menu.

If you download 7zip, make sure you don't get the one with hidden junk.

 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on May 31, 2014, 09:54:35 pm
How do you make sure you did not get the one with JUNK? ???
Title: Re: $20 LCR ESR Transistor checker project
Post by: Retep on May 31, 2014, 10:04:51 pm
Also, could this version be upgraded to the latest version just by upgrading the processor  :-+ :--

http://www.ebay.co.uk/itm/NEW-TRANSISTOR-TESTER-NPN-PNP-MOSFET-THYRISTOR-DIODE-RESISTOR-CAPACITOR-METER-/261192428249?pt=LH_DefaultDomain_0&hash=item3cd0482ad9 (http://www.ebay.co.uk/itm/NEW-TRANSISTOR-TESTER-NPN-PNP-MOSFET-THYRISTOR-DIODE-RESISTOR-CAPACITOR-METER-/261192428249?pt=LH_DefaultDomain_0&hash=item3cd0482ad9)

as it only costs 12 dollars and has a socketed processor
Looking at the photo this one seems to have a ATMega8 processor. The ATMega8 processor doesn't have enough memory for all the features in the later software versions. Personally I would spend a few dollars more to get one with a (socketed) ATMega328 processor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on May 31, 2014, 10:23:44 pm
How do you make sure you did not get the one with JUNK? ???

 Same question. And does no one have the english manual pdf hosted somewhere?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mr Smiley on May 31, 2014, 10:35:50 pm
Hi,

I've looked around and there are no reports of bloatware included with the install.

I use Linux, otherwise i would have installed it to see  :-/O When i did use windows, i used 7zip.

As for the Atmega8, yes i knew that, that's why i wondered if just popping in a 328 would be all that was needed, i was also thinking of using one of those cheep Clones, the arduino pro mini, changing the xtal to 8Mhz and adding a lcd which i have a few of  :-//

 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: intrax on June 03, 2014, 04:51:29 pm
Can any of these ones do 'in circuit' testing of (discharged) capacitors or is there an easy fix possible so that they can?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on June 03, 2014, 05:02:46 pm
Yes, the latest firmware brings a special function in menu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: intrax on June 03, 2014, 06:10:04 pm
Yes, the latest firmware brings a special function in menu.
Probably only working on atmega328… any link to a suitable model on ebay?  Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 03, 2014, 06:14:59 pm
Yes, the latest firmware brings a special function in menu.
Probably only working on atmega328… any link to a suitable model on ebay?  Thanks.

Yep! Take any clone with an ATmega328 and flash the latest firmware. Both firmware branches (k and m) support in circuit capacitance and ESR checks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: intrax on June 03, 2014, 06:19:48 pm
Yes, the latest firmware brings a special function in menu.
Probably only working on atmega328… any link to a suitable model on ebay?  Thanks.

Yep! Take any clone with an ATmega328 and flash the latest firmware. Both firmware branches (k and m) support in circuit capacitance and ESR checks.
Any ? I do like the graphics display's… ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: robimarko on June 03, 2014, 08:27:50 pm
I am looking to buy this one:http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=281314227233&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en

I need esr and capacitance measurment really often and i dont have money for a standard meter.

Can that version be updated with latest firmware?
And can you link some versions of firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 03, 2014, 08:31:11 pm
Any ? I do like the graphics display's… ;D

The Wumpus will get you  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on June 03, 2014, 08:34:09 pm
I am looking to buy this one:http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=281314227233&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en

I need esr and capacitance measurment really often and i dont have money for a standard meter.

Can that version be updated with latest firmware?
And can you link some versions of firmware?

I guess you should ask the seller for the firmware source before buying those versions.. and find out if the icsp port is available for firmware uploads. ( I have newer found better pictures of these, showing the backside etc)
Title: Re: $20 LCR ESR Transistor checker project
Post by: eevbstedt on June 03, 2014, 08:50:33 pm
I am looking to buy this one:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=281314227233
 (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=281314227233)
The description reminds me of the last one I bought. 

'Latest Firmware' they said.
'What version is that?', I asked.
'The latest!', they said.

Turns out their definition of latest is 1.07k.  =/
Title: Re: $20 LCR ESR Transistor checker project
Post by: robimarko on June 03, 2014, 08:59:28 pm
That version is just an example,i sent a message to seller.
But most likely i will have to buy standard socketed 328 version with 16x02 lcd

Somebody got a recommendation?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 03, 2014, 09:36:37 pm
I am looking to buy this one:http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=281314227233&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en

I need esr and capacitance measurment really often and i dont have money for a standard meter.

Can that version be updated with latest firmware?

That clone uses a graphics LCD which requires some custom firmware modifications.

Quote
And can you link some versions of firmware?

The latest and greatest is available at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/) ('trunk' for the k-firmware and 'Markus' for the m-firmware).
Title: Re: $20 LCR ESR Transistor checker project
Post by: AintBigAintClever on June 03, 2014, 10:15:23 pm
I bought http://www.ebay.com/itm/190949271460 (http://www.ebay.com/itm/190949271460) which came with 1.10k firmware and the extra menus.

Main IC is a socketed 328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on June 03, 2014, 10:27:54 pm
did you take some pictures of its inside?
Title: Re: $20 LCR ESR Transistor checker project
Post by: robimarko on June 04, 2014, 07:12:03 am
I bought http://www.ebay.com/itm/190949271460 (http://www.ebay.com/itm/190949271460) which came with 1.10k firmware and the extra menus.

Main IC is a socketed 328.

And off course seller does not send it to Croatia
Title: Re: $20 LCR ESR Transistor checker project
Post by: AintBigAintClever on June 04, 2014, 10:36:30 pm
Try this one, then. Looks identical, my guess is that the insides will be, too. Croatia not on the postal exclusions this time.
www.ebay.com/itm/181109931348 (http://www.ebay.com/itm/181109931348)

Pictures of the inside of mine attached.

Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on June 05, 2014, 07:39:14 am
looks good.. Strange that nobody adds the programming headers :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: AintBigAintClever on June 05, 2014, 10:41:45 am
Keeps the cost down I suppose. Why spend a few pence on a header when you can just NOT do it instead? Besides, if the IC is socketed it can be removed for programming.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on June 05, 2014, 10:44:19 am
the header I can solder myself, but the pinout.. holes.. are those really expensive ? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 05, 2014, 11:11:09 am
Try this one, then. Looks identical, my guess is that the insides will be, too. Croatia not on the postal exclusions this time.
www.ebay.com/itm/181109931348 (http://www.ebay.com/itm/181109931348)

Pictures of the inside of mine attached.

The cap for buffering AREF is missing (C1 in your case). By adding a 1nF ceramic cap you could stabilize the reference voltage of the ADC.
Title: Re: $20 LCR ESR Transistor checker project
Post by: intrax on June 05, 2014, 05:09:55 pm
the header I can solder myself, but the pinout.. holes.. are those really expensive ? :)
Any links to a version including header?  O0
I have not seen one,  which one is best for in circuit testing ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on June 05, 2014, 06:07:49 pm
the header I can solder myself, but the pinout.. holes.. are those really expensive ? :)
Any links to a version including header?  O0
I have not seen one,  which one is best for in circuit testing ?

 One problem attempting to use any ICSP is that the chip has external components wired to pins (I don't yet have a schematic so others would have to check for you) so they may very well interfere with the external programmer operation.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 05, 2014, 08:45:30 pm
the header I can solder myself, but the pinout.. holes.. are those really expensive ? :)
Any links to a version including header?  O0
I have not seen one,  which one is best for in circuit testing ?

Most clones without an enclosure got the pads for the ISP header (hidden below the LCD module).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 05, 2014, 08:50:11 pm
One problem attempting to use any ICSP is that the chip has external components wired to pins (I don't yet have a schematic so others would have to check for you) so they may very well interfere with the external programmer operation.

No worries, it's designed to work fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on June 06, 2014, 09:52:26 pm
My component tester is almost finished so I made a video. The front panel is under construction.
Universal component avr tester with ATmega328 (https://www.youtube.com/watch?v=NCSb3vqkbqA#)
Well, there are many such videos on youtube. Nothing new really.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robimarko on June 07, 2014, 04:05:30 pm
At end i bought this one
http://www.ebay.com/itm/281206556098?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 (http://www.ebay.com/itm/281206556098?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)

It has socketed DIP Atmega328 so even if it has old firmware revision i can flash it to latest with my arduino
Title: Re: $20 LCR ESR Transistor checker project
Post by: eevbstedt on June 08, 2014, 01:50:56 pm
At end i bought this one
http://www.ebay.com/itm/281206556098?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 (http://www.ebay.com/itm/281206556098?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)
That looks the same at the last one I got but is a different seller.  Ask them what version of firmware it comes with.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: robimarko on June 08, 2014, 02:32:59 pm
I asked and seller has no idea,he just verified that it has socketed Atmega328,so i will be able to update it if it comes with old version
Title: Re: $20 LCR ESR Transistor checker project
Post by: eevbstedt on June 08, 2014, 04:03:20 pm
I asked and seller has no idea ...
Thanks for doing that and the feedback.  At least that seller is honest!  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on June 08, 2014, 06:34:21 pm
Will any of these take measurements in circuit? I have been trying to follow the thread but get lost with all the jumping around. Is it that none of these will until you update the firmware? There are some of the responses that say to add parts. I am sure that you can't add the same parts to everyone of these or do you? I wish there was a simple answer as to which one to buy, then update like this, and add these parts and you will have a all working in circuit tester. Sorry but I get where I think I understand and then someone comes up with something else and then I am lost. I am just a nube and need some help.
Thanks for any answers.
Don https://www.eevblog.com/forum/Smileys/default/bangheadonwall.gif (https://www.eevblog.com/forum/Smileys/default/bangheadonwall.gif)
Title: Re: $20 LCR ESR Transistor checker project
Post by: AintBigAintClever on June 08, 2014, 06:52:00 pm
The trouble with in-circuit testing is that you're not just testing the component, you're testing the component in parallel with all the other gubbins that's connected across the same pins. Whatever result you get, I don't think you can trust it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robimarko on June 08, 2014, 07:47:57 pm
I think that only thing that you can measure in circuit is ESR of caps,hope that I am not wrong
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 08, 2014, 08:00:39 pm
Will any of these take measurements in circuit?

The current firmware (from the project's web site) supports in-circuit capacitance and ESR measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on June 08, 2014, 08:08:23 pm
Thanks for the replies. Now, which one would be a good low price one that can use the latest updates and how about someone showing some ways to do the update for the rest of us that are not sure how to do it. In my case I have not updated firmware in a while on anything even though I have several different units to do the updates. As I remember, it gets confusing as you have to get the computer to talk and recognize the updater and then there are several different programs to use and they are all different. A simple YouTube video for updating these cards would be great. I don't have a lot of money to just waste buying different ones until I find one that works, so suggestions would be great!
Thanks again.
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 08, 2014, 08:11:15 pm
The trouble with in-circuit testing is that you're not just testing the component, you're testing the component in parallel with all the other gubbins that's connected across the same pins. Whatever result you get, I don't think you can trust it.

Of course the circuit around the cap will influence the result, but it's sufficient to get a ballpark figure. I've tested a lot of circuits while writing the code for the in-circuit ESR measurement of the m-firmware and in most cases the values were off by about 10% at maximum. I was a little bit suprised since I was expecting a larger difference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 08, 2014, 08:38:19 pm
Thanks for the replies. Now, which one would be a good low price one that can use the latest updates and how about someone showing some ways to do the update for the rest of us that are not sure how to do it. In my case I have not updated firmware in a while on anything even though I have several different units to do the updates. As I remember, it gets confusing as you have to get the computer to talk and recognize the updater and then there are several different programs to use and they are all different. A simple YouTube video for updating these cards would be great. I don't have a lot of money to just waste buying different ones until I find one that works, so suggestions would be great!
Thanks again.
Don

Any clone with an ATmega328 and a 2*16 LCD module is fine. For updating the firmware you can use an inexpensive ISP programmer, even an Arduino. If possible please add an ISP header to the tester. Otherwise you would have to breadboard something, First, you download the current firmware, update Makefile and config.h to match your hardware and compile the firmware. AVR Studio or avr-gcc are recommended. Then you use the ISP programmer to flash the firmware including the EEPROM. I'm using the Diamex ALL-AVR with avrdude under Linux for example (just a simple 'make upload').
Title: Re: $20 LCR ESR Transistor checker project
Post by: robimarko on June 08, 2014, 09:13:16 pm
If you need to update MAKEFILE and config.h that will stop me from updating because i am not really into microcontroller programming
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on June 08, 2014, 09:17:20 pm
If you need to update MAKEFILE and config.h that will stop me from updating because i am not really into microcontroller programming

I will go you one better, I don't know what that is or how to do it! That is one reason I was hoping someone would make a video on it!
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 08, 2014, 09:33:13 pm
If you need to update MAKEFILE and config.h that will stop me from updating because i am not really into microcontroller programming

Karl-Heinz provides some compiled firmwares of the current version for standard setups in the SVN repo. Anyway, it's a good idea to learn about MCUs and tool chains.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 08, 2014, 09:48:12 pm
I will go you one better, I don't know what that is or how to do it! That is one reason I was hoping someone would make a video on it!
Don

There are tons of videos about programming ATmegas. Those also apply to the Transistortester. Please see
Programming AVR with Arduino (https://www.youtube.com/watch?v=_ZL-YNOH_jA#ws)
for an example with an arduino used as programmer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on June 08, 2014, 10:03:16 pm
Thanks for the replies. Now, which one would be a good low price one that can use the latest updates and how about someone showing some ways to do the update for the rest of us that are not sure how to do it. In my case I have not updated firmware in a while on anything even though I have several different units to do the updates. As I remember, it gets confusing as you have to get the computer to talk and recognize the updater and then there are several different programs to use and they are all different. A simple YouTube video for updating these cards would be great. I don't have a lot of money to just waste buying different ones until I find one that works, so suggestions would be great!
Thanks again.
Don

Any clone with an ATmega328 and a 2*16 LCD module is fine. For updating the firmware you can use an inexpensive ISP programmer, even an Arduino. If possible please add an ISP header to the tester. Otherwise you would have to breadboard something, First, you download the current firmware, update Makefile and config.h to match your hardware and compile the firmware. AVR Studio or avr-gcc are recommended. Then you use the ISP programmer to flash the firmware including the EEPROM. I'm using the Diamex ALL-AVR with avrdude under Linux for example (just a simple 'make upload').

What fuse byte values does your project use? The firmware does not include that information, most likely embedded in the makefile?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 08, 2014, 10:13:57 pm
What fuse byte values does your project use? The firmware does not include that information, most likely embedded in the makefile?

Yep, the Makefile supports several ATmega types in different configurations. Basically the default values are used and just the clock source and clock divider need to be changed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on June 09, 2014, 12:14:04 am
Here is schematic and PCB of my version of component tester. (http://youtu.be/NCSb3vqkbqA)
I use the firmware made by Karl Heinz Kübbeler.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on June 09, 2014, 01:18:55 am
Thanks for the schematic.
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on June 10, 2014, 12:25:57 am
Well, I made just some minor changes. Karl Heinz Kübbeler has the credits, he has done the whole job.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jimjam on June 11, 2014, 06:00:31 pm
Here is schematic and PCB of my version of component tester. (http://youtu.be/NCSb3vqkbqA)
I use the firmware made by Karl Heinz Kübbeler.
Thank you! Can you tell me:

- What software did you use to draw the diagram and create the PCB layout?
- a noob question: how did you then create the PCB?
-  What are the differences / advantages does this have vs the $20 Chinese version?

This looks like it's going to take a looooong time to create, from doing the PCB, buying the parts etc.... The parts alone will cost far more than $20 :) Probably cheaper to buy a real LCR meter, although this seems cooler :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on June 12, 2014, 01:07:06 am
Thank you! Can you tell me:
A) - What software did you use to draw the diagram and create the PCB layout?
B) - a noob question: how did you then create the PCB?
C) -  What are the differences / advantages does this have vs the $20 Chinese version?

D) - This looks like it's going to take a looooong time to create, from doing the PCB, buying the parts etc.... The parts alone will cost far more than $20
A) I used Eagle Version 5.11.0 from http://www.cadsoftusa.com/eagle-pcb-design-software/?lang=en (http://www.cadsoftusa.com/eagle-pcb-design-software/?lang=en)
B) It was made at my university in semi-professional way. I paid for it.

C) You can use a single layer PCB. Two types of LCD connectors are possible. There is added a reset button and a status LED, that indicates that the MCU is alive even if LCD is wrong or absent. You can use a 7V to 15V ac adaptor and there is an ovevoltage protection. On the other hand, my version needn't be neccesarily better than the Chinese one, I just built it according to my needs.

D) Well, it took a long time, but it is my hobby. Somebody gave me that metal housing and old LCDs so I did not have to pay for them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on June 12, 2014, 01:09:41 am
Probably cheaper to buy a real LCR meter, although this seems cooler :)
I already have that CEM DT-9935. https://www.eevblog.com/forum/testgear/cheap-lcr-meter-cem-dt-9935/ (https://www.eevblog.com/forum/testgear/cheap-lcr-meter-cem-dt-9935/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Richard Crowley on June 16, 2014, 05:40:43 am
I apologize that I didn''t slog through all 495 previous posts in this thread.
But I just received a kit from an Ebay vendor and at first inspection, it looks good.
However, there is no documentation, even a schematic diagram.
Is the board layout and schematic diagram available online somewhere?
A quick Google search didn't reveal anything promising.

I am going to be asking the  Ebay vendor also, but they appear to sell everything from soup to nuts and they don't appear to be much into electronics.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 16, 2014, 11:22:15 am
However, there is no documentation, even a schematic diagram.
Is the board layout and schematic diagram available online somewhere?
A quick Google search didn't reveal anything promising.

You'll find the official documentation at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/) (select the directory and click "Download GNU tarball"). The clones vary in their layouts, but mostly follow the schematic in the documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 16, 2014, 11:49:27 am
New features in the current k-firmware:
- support of encoder with push button for the UI
- support of graphical 128x64 LCD module based on ST7565
- frequency measurement
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on June 16, 2014, 01:42:01 pm
Nice!

I was looking to add support for Nokia's 84x48 gLCDs (PCD8544 based). Those modules are really cheap. I guess it will be easier now.

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Richard Crowley on June 16, 2014, 08:55:21 pm
You'll find the official documentation at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/) (select the directory and click "Download GNU tarball"). The clones vary in their layouts, but mostly follow the schematic in the documentation.

Thank you, madires.   :-+

There is some difference between my board and the official schematic.
I am creating an "as built" schematic of my variant. 
Is there a wiki or something for this product where I can post it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 16, 2014, 09:04:18 pm
I am creating an "as built" schematic of my variant. 
Is there a wiki or something for this product where I can post it?

I'd suggest to post it here or to send it to Karl-Heinz (please see the first page of the documentation for his email address).
Title: Re: $20 LCR ESR Transistor checker project
Post by: jimjam on June 17, 2014, 01:13:26 pm
slightly off topic.... how did you create your PCB, madires? I downloaded your schematic + pcb layout, but as a noob, I am wondering what's the best way for me to create the PCB. I can go the whole shebang with getting a photoresist pcb, UV lamp, etchant etc, and I might use it again in the future.... but I'm curious how other people do it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on June 17, 2014, 01:53:55 pm
They order it from places like the ones mentioned in the cheap PCBs for low volume thread (https://www.eevblog.com/forum/manufacture/cheap-pcbs-for-really-low-volume/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 17, 2014, 03:01:33 pm
slightly off topic.... how did you create your PCB, madires? I downloaded your schematic + pcb layout, but as a noob, I am wondering what's the best way for me to create the PCB. I can go the whole shebang with getting a photoresist pcb, UV lamp, etchant etc, and I might use it again in the future.... but I'm curious how other people do it.

Since I already own all the tools I make PCBs myself but if I'd have to buy everything new I'd consider one of those inexpensive PCB services. I can't make vias or print nice soldermasks and silkscreens. In the TransistorTester thread of the microcontroller.net forum some people are organizing a centralised buying from time to time. For you, down under, a PCB service in China could be a good choice.

BTW: Regarding the schematic, it might be better to have D0-D3 of the LCD module floating instead of the ground connection. As I just learnt in another thread the data lines are pulled up internally by the module.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jimjam on June 18, 2014, 01:06:39 pm
How much work is it to make your own pcb? Do you consider it a big deal / a full day project? But even so, it beats waiting for 2 weeks. There's also that PCB printer that Dave was showing from CEBIT....
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on June 18, 2014, 02:42:05 pm
So with my current process, I'm at about an hour per a panel including cleanup. I have the gear to make double-sided panels of A4 size. Then it's cutting, drilling the holes and s.o. which adds another 20 minutes. I'd say that's pretty fast.

Still I don't think it's worth it, most of the time. Even if you earn exceptionally little, making a panel is about 25$ total in time and material. About the same that DirtyPCB charges. But with them, you get it without lifting a finger and with much better quality. Making your own boards means making a lot of mess and keeping supplies around the house. Cleaning up the former is annoying work. I like my day job much much better. So I'd charge much more for an hour of PCB making, than just what I make at my day job. Storing the supplies is also annoying and takes up considerable space, even further adding to the perceived costs of board making. And on top of that, you have to design the boards more carefully than you otherwise would. You can't use that fine a trace, that many vias and so on.

The only argument for make your own PCBs is: "But I get my boards faster that way". It's not a strong argument though, because let's face it:
You rarely have all the parts, you need at hand. You'll almost always have to wait for a mail order of something - you might as well spend that time waiting for components and ordered boards.

Bottom line: Only sadist or very very time pressed people manufacture PCBs at home.
Title: Re: $20 LCR ESR Transistor checker project
Post by: senz_90 on June 18, 2014, 06:54:52 pm
Sorry for my ignorance, I am really new on this microcontroller things, please bear with me. This project looks like will give me a good experience to begin about microcontroller. I have read several article and download it from german site and another site, since my mother's language is not english I am getting hard to understand how to modify the source code Makefile with compiler software. So let's the question begin :

1. If I am gonna use 16x2 lcd and english language with my tester, what is word that I need to change from makefile with compiler?
2. If I am gonna use Atmega168, how to set the fuse bit with kazama software? And If I wanna use Atmega328, how to set it?
what If I wanna use internal clock like 8Mhz? or external crystal 8Mhz? I have read several guide about fuse bits but I am really confuse. I hope someone wanna help me with some picture and I am really appreciated it.

Thank you


Title: Re: $20 LCR ESR Transistor checker project
Post by: Mr Smiley on June 18, 2014, 08:27:00 pm
Hi,

This will help a little with understanding fuses


 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 18, 2014, 09:48:44 pm
1. If I am gonna use 16x2 lcd and english language with my tester, what is word that I need to change from makefile with compiler?

UI_LANGUAGE = LANG_ENGLISH
Support for a 16x2 LCD module is set by default.

Quote
2. If I am gonna use Atmega168, how to set the fuse bit with kazama software? And If I wanna use Atmega328, how to set it?
what If I wanna use internal clock like 8Mhz? or external crystal 8Mhz? I have read several guide about fuse bits but I am really confuse. I hope someone wanna help me with some picture and I am really appreciated it.

You can get the fuse bits from setup.mk for the different ATmegas and clocks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hdlg_zhangyu on June 27, 2014, 10:35:15 pm
I am new here and also a newbie for electronics. I got mine today from ebay. It is with Atmel Mega328p AU chip, it impressed me with all SMD components and even with a Tantalum capacitor!
However, they failed to acknowledge Karl-Heinz K"ubbeler, madires and everyone else who contributed to the firmware design.

The seller claimed it is 2014 "latest" version. However when started the program, it showed:
"Transistor Tester V2.1". Wondering what exactly firmware it is running.

ALso, I am planning to upgrade the firmware anyway to the newest version using the ISP port, I am actually wondering what version of LCD should I use? Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: g***! on June 27, 2014, 11:26:15 pm
Look at post 498....my board was identical to yours , worked for me1
Title: Re: $20 LCR ESR Transistor checker project
Post by: hdlg_zhangyu on June 28, 2014, 12:54:24 am
Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: at2marty on June 28, 2014, 03:49:20 pm
I've read quite a bit about this project and am in the early stages of adapting it with a few minor modifications.  For the most part, most of what I plan will remain the same, but I chose to use an ATMega1284p so that I could do a few other things with it.

Perfect timing :-) Karl-Heinz has started to work on an  ATmega324/644/1284 version.

O.K. I'm finally ready to get back to this project.  I do have a few questions though.

I have downloaded the latest tarball, and started poking around a bit.  I'm assuming that the latest source for the project is in the Software/trunk directory, is that correct?  What is the difference between the stuff in the Markus directory and the tags directory?

In the Doku/tags directory, is there an easy way to translate the changelog.txt file from German to English?

Finally, I still would like to use an ATMega 1284p for my build.  Has a schematic or board layout been done or is work in progress with this?  If not, I am willing to do this and contribute to the project.  I personally prefer through hole, so that's how I would do it.  I don't want to start on it if someone else is already doing the work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on June 28, 2014, 03:55:26 pm
I've had my tester for about a month now. Yesterday I decided to pull the 328p from it's socket and install it in my USBasp programmer with ZIF adapter with the intent of reading the flash and fuse bytes using AVRDUDE so that I could make a duplicate/spare controller.

 On trying I was only able to obtain a HEX file that was empty. On looking at the lock bits (0x3C) and checking with the datasheet it seems the chip is disabled from reading it's flash contents and prevented from being able to change the lock bits.

 I wonder if anyone else has checked there controller chip to see if it's common for the seller/maker to 'protect' the firmware?


http://www.ebay.com/itm/291041497713?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/291041497713?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
Title: Re: $20 LCR ESR Transistor checker project
Post by: at2marty on June 28, 2014, 04:11:17 pm
I've had my tester for about a month now. Yesterday I decided to pull the 328p from it's socket and install it in my USBasp programmer with ZIF adapter with the intent of reading the flash and fuse bytes using AVRDUDE so that I could make a duplicate/spare controller.

 On trying I was only able to obtain a HEX file that was empty. On looking at the lock bits (0x3C) and checking with the datasheet it seems the chip is disabled from reading it's flash contents and prevented from being able to change the lock bits.

 I wonder if anyone else has checked there controller chip to see if it's common for the seller/maker to 'protect' the firmware?


http://www.ebay.com/itm/291041497713?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/291041497713?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

Hmm... I can't help you much as far as getting a good HEX image of what is on the chip.  You can change the lock bits back to default by writing a new program to it, but it will erase anything that is currently on it.

I would suggest downloading the latest firmware and use it as your spare.
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on June 28, 2014, 04:37:08 pm
Quote
I would suggest downloading the latest firmware and use it as your spare.

 Thanks.

 I looked into that but I don't have a proper unpacker/decompressor program on my new Win 8.1 machine and just didn't want to proceed with looking for one. If someone could provide a direct link to a hex file that would be cool, otherwise no big deal just something I was playing with. If unit ever dies I would have no problem with spending another $20 for a new one as it's that cool of a device.

Title: Re: $20 LCR ESR Transistor checker project
Post by: at2marty on June 28, 2014, 05:55:43 pm
Quote
I would suggest downloading the latest firmware and use it as your spare.

 Thanks.

 I looked into that but I don't have a proper unpacker/decompressor program on my new Win 8.1 machine and just didn't want to proceed with looking for one. If someone could provide a direct link to a hex file that would be cool, otherwise no big deal just something I was playing with. If unit ever dies I would have no problem with spending another $20 for a new one as it's that cool of a device.

I would be willing to do that for you, but I don't think that it's right for me to distribute the file from a source other than the official site.  I believe that you might be able to download it directly from the official site by going to http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/) and save the hex file from there.

I'm not familiar at all with Windows 8.1, but I do know that a program called 7zip will unpack a tarball.  I would suggest downloading it from the official website http://www.7-zip.org/ (http://www.7-zip.org/)

If you choose 7zip, you will have to extract it twice.  The first time you will end up with a filename.tar .  Extract filename.tar to actually get the real file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on June 28, 2014, 06:52:33 pm
Thanks for the info, but it's more complex and bother then I'm willing to go through.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on June 28, 2014, 07:04:02 pm
Thanks for the info, but it's more complex and bother then I'm willing to go through.
...This has made my head explode  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on June 28, 2014, 08:00:48 pm
Thanks for the info, but it's more complex and bother then I'm willing to go through.
...This has made my head explode  |O

I'd have that looked at if I was you.  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 28, 2014, 08:45:44 pm
I have downloaded the latest tarball, and started poking around a bit.  I'm assuming that the latest source for the project is in the Software/trunk directory, is that correct?  What is the difference between the stuff in the Markus directory and the tags directory?

Yes, the current k-firmware version under development is in the trunk directory. The tags directory contains old k-firmware releases and the Markus directory got the m-firmware releases.

Quote
In the Doku/tags directory, is there an easy way to translate the changelog.txt file from German to English?

Some online translation tool? Please ask Karl-Heinz if he would also provide an English version.

Quote
Finally, I still would like to use an ATMega 1284p for my build.  Has a schematic or board layout been done or is work in progress with this?  If not, I am willing to do this and contribute to the project.  I personally prefer through hole, so that's how I would do it.  I don't want to start on it if someone else is already doing the work.

AFAIK there's no ATmega 1284 based PCB yet and I'm sure that Karl-Heinz would put your contribution into the repo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on June 29, 2014, 12:56:21 am
Interesting project!
I just needed to repair a Sansui AU-6500 amplifier that had lots of bad transistors so I had to breadboard something to test them. I'm definitely building this!
So really, we should make a pcb and declare it "official" (with the original designer's permission of course) and stop supporting the Chinese. Plus, it would be a good exercise in building something and you get to learn stuff on the way. Maybe a group buy for PCBs? Double sided.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dannyf on June 29, 2014, 01:08:25 am
Quote
stop supporting the Chinese.

Hurting someone should never be the goal until you get something out of it.

Do things because it is good for you. Not because it is bad for others.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on June 29, 2014, 02:16:00 am
I should have been more elaborate in my statement. The thing is that people want it fast and cheap. I didn't mean to hurt any race whatsoever, I was just addressing the plethora of cheap electronics made with crappy parts that are coming out of Asia. Even thou they "work" out of the box I don't think that it's good overall to stimulate the Asian market while the local producers are complaining about lack of income/customers. I'm more of a "keep it in the family" guy and I don't really like the "it's kind of working and it's cheap" strategy that the Asian market deployed over the whole world. Once again, I stress to mention that I don't have anything with Asian people. My only problem is that they "lure" everyone with cheap, low quality stuff. Sure, there are some sellers that found a good balance and I salute them, but since they rip off a design, use cheap parts and make money out of it isn't something I applaud them for.
I didn't mean to cause no harm and hope we don't get off topic.
Once again, I stress that we should make a sort of "official" pcb that we could build ourselves :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on June 29, 2014, 03:10:07 am
In the U.S. some people say to not buy from Asia but to buy Made in the USA. If you take a look at a majority of things marked made in the USA you will see it was made in Asia and or Mexico and just remarked made in the us and the local company is making a huge profit. I buy a lot of my remote control equipment direct from China as I don't have the money to give to large local company's for their CEO's to have large home's. I can buy the same item in the US for around 4 times what is costs me shipped from China or buy 4 time the equipment and enjoy it for the same cost. Either way, no one in the usa gets a job from it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dannyf on June 29, 2014, 09:11:38 am
Quote
while the local producers are complaining about lack of income/customers.

They can always provider a better product / service at a lower price to win back customers.

I mean, that's competition. No amount of proping up does anyone any favor over the long term.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nessatse on June 29, 2014, 09:20:18 am
Here is my take on the tester that fits into the 'standard' 50mmx50mm form factor. I'll be sending the pcb for fab this week hopefully, which means another 4-6 weeks before I get to put it all together.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 29, 2014, 11:37:28 am
So really, we should make a pcb and declare it "official" (with the original designer's permission of course) and stop supporting the Chinese. Plus, it would be a good exercise in building something and you get to learn stuff on the way. Maybe a group buy for PCBs? Double sided.

You don't have to reinvent the wheel ;) In the project's thread at the microcontroller.net forum you'll find several PCB layouts, and some people are organizing group buys from time to time. But I haven't seen any PCB with all the hardware options included yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on June 29, 2014, 11:40:05 am
free_electron was going to design a pvb.

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torr032 on July 01, 2014, 12:11:26 am
I am from Europe and I would rather buy something from China then from the USA because U.S terrorize the whole world with their military army by attacking other countries.
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on July 01, 2014, 12:55:29 am
I am from Europe and I would rather buy something from China then from the USA because U.S terrorize the whole world with their military army by attacking other countries.

 Well I've always said that people should always vote with their wallets.

Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 01, 2014, 02:57:20 am
I am from Europe and I would rather buy something from China then from the USA because U.S terrorize the whole world with their military army by attacking other countries.

Why wouldn't you buy it from Europe instead? :)

On topic:
I worked a bit to make a through hole pcb for this project, by adding a relay for protection from charged capacitors, and a dc-dc converter for Zener measurement. I saw some designs that had that but I don't like to solder smd, at least not yet. And I want to socket the 328. I might be building on a board that was made available by a user on this thread but I don't know if I can keep it single sided. If not than I'll scrap it and make it double layer.

Offtopic:
I said it before and I'll say it again:
Economic health is maintained by each and one of us. The flow of our personal cash (yes, even the 20$ for a LCR meter) dictates the future of our country's/region's economy.
You complain that something made in the US/EU costs 2-3 times what it costs in Asia, but you don't think that the money that you give for that product comes back to you one way or another. It stays in your market. It doesn't leave the country. You buy a LCR meter from someone, he buys something else from your company etc.
 You want to buy something cheap from Asia, yet you demand a larger salary from your company. Basically you're a sink hole :)
Yes, it's tempting to buy something cheap from somewhere else but I guess that the main problem is financial education.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torr032 on July 01, 2014, 11:18:52 am
Sure, I would certainly rather buy something from Germany then from China if it is the same price. But that is hard to find, almost every product that you can not find in your local stores, it is hard to beat the chinese with the product price + shipping costs. I heard that more than half of the world production of everything is coming from China, so why to buy something from the resellers at the higher price if time is not an issue and you can wait for the postman.
Also they are growing in the product quality and are able to manufacture good quality devices on their own.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 01, 2014, 11:26:50 am
Yes, but by that standard, you are basically lowering the quality of life of your own country on the long run. I mean, basically you are asking your own country's sellers of the same items to work for the same money that the people that are selling the items from Asia are working for. I mean, indirectly you are condemning yourself in the future to the same grim quality of life that Asian people working in obscure factories are having. That's simple logic. You can't have items that cheap and still get payed a good amount of money every month.
Think on the long run, after Asia get a huge load of money from the rest of the developed parts of the world, and let's assume that that money gets distributed among the Asian people, they will no longer want to work for the amount that they are working for. They will have your money and they won't need to work for less. So this way you are increasing their quality of life and at the same time you are lowering yours.
Please, don't replay again with "but it's cheaper" :)

Of course this applies for stuff that you can get locally. If there's something that you need and you can only find it there...well, that's their gain, and is good for them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torr032 on July 01, 2014, 12:53:33 pm
Production is what matter. Now you can buy everything except food on the internet, so the trade business is not profitable as it was before.

China is fine for me, they don't use money for bombarding other countries or to create crisis in the world. People work hard so they could escape from poverty, buying chinese goods for me is some sort of a patriotism, hey lets spread the world wealth more evenly in the world. While some ppl on the world are dying from hunger it is not fair that some countries especially western ones are that rich.
I am also buying on the internet since I know how to do that. Buying chinese goods in local shops is for ppl that don't know how to buy on net or when time matter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 01, 2014, 12:59:26 pm
I worked a bit to make a through hole pcb for this project, by adding a relay for protection from charged capacitors, and a dc-dc converter for Zener measurement. I saw some designs that had that but I don't like to solder smd, at least not yet. And I want to socket the 328. I might be building on a board that was made available by a user on this thread but I don't know if I can keep it single sided. If not than I'll scrap it and make it double layer.

The latest add-ons are an input stage for frequency counting and a mechanical encoder (left/right/push button) for the UI. We'll keep you busy ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on July 01, 2014, 01:48:31 pm
  If I were mainland Chinese, I would not mind and shall be very happy if you spend your time doing the $20 tester, which shall cost you maybe $50-$200, and maybe another $1000s of opportunity cost.  In no time, we can delegate the $20 tester away to you and focus on the much higher value stuff, and take more holidays without working so hard.   Maybe you can do a higher value kits or complete tester with all the latest?  This shall be more constructive.  If the price is reasonable, I shall buy and I don't think the mainlan Chinese mind buying from you as they do not mind buying expensive quality European, Japanese or American products, of course provided you want to sell to them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 01, 2014, 08:12:42 pm
I worked a bit to make a through hole pcb for this project, by adding a relay for protection from charged capacitors, and a dc-dc converter for Zener measurement. I saw some designs that had that but I don't like to solder smd, at least not yet. And I want to socket the 328. I might be building on a board that was made available by a user on this thread but I don't know if I can keep it single sided. If not than I'll scrap it and make it double layer.

The latest add-ons are an input stage for frequency counting and a mechanical encoder (left/right/push button) for the UI. We'll keep you busy ;)

Sure! Any documentation on the input stage? Need to sort through the Eagle library for that encoder but I can find some space on board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 01, 2014, 08:24:58 pm
Sure! Any documentation on the input stage? Need to sort through the Eagle library for that encoder but I can find some space on board.

Please download http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/) and see ttester.pdf.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 02, 2014, 09:56:06 am
Production is what matter. Now you can buy everything except food on the internet, so the trade business is not profitable as it was before.

China is fine for me, they don't use money for bombarding other countries or to create crisis in the world. People work hard so they could escape from poverty, buying chinese goods for me is some sort of a patriotism, hey lets spread the world wealth more evenly in the world. While some ppl on the world are dying from hunger it is not fair that some countries especially western ones are that rich.
I am also buying on the internet since I know how to do that. Buying chinese goods in local shops is for ppl that don't know how to buy on net or when time matter.

Sadly, most of the money that go to China is centralized into few groups that have government connections. Chinese people see little money from what you are sending in.
Then about the wealth of the country, it depends on the decisions made by the local powers.
So basically you are making a select group of people more wealthy, while the poor struggle. And guess where that money ends up being used? Military power!
Although I agree on helping people that need help, I'm firstly thinking of my own people :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 02, 2014, 10:07:27 am
Sure! Any documentation on the input stage? Need to sort through the Eagle library for that encoder but I can find some space on board.

Please download http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/) and see ttester.pdf.

I looked at it and will have a go tonight. Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: dannyf on July 02, 2014, 11:31:35 am
Quote
Sadly, most of the money that go to China is centralized...

Time for a reality check.

Title: Re: $20 LCR ESR Transistor checker project
Post by: senz_90 on July 02, 2014, 08:08:34 pm
thank you madires, and Mark Heinz for this cool tester, I am still waiting my lcd come, and I am really new to this programming stuff. I hope I could make this, or maybe I would try basic program first to get familiar with this microcontroller things. once again thank you for you all make this cool stuff.

sorry for late reply. hahaha...
Title: Re: $20 LCR ESR Transistor checker project
Post by: hdlg_zhangyu on July 02, 2014, 08:30:17 pm
I am new here and also a newbie for electronics. I got mine today from ebay. It is with Atmel Mega328p AU chip, it impressed me with all SMD components and even with a Tantalum capacitor!
However, they failed to acknowledge Karl-Heinz K"ubbeler, madires and everyone else who contributed to the firmware design.

The seller claimed it is 2014 "latest" version. However when started the program, it showed:
"Transistor Tester V2.1". Wondering what exactly firmware it is running.

ALso, I am planning to upgrade the firmware anyway to the newest version using the ISP port, I am actually wondering what version of LCD should I use? Thanks!

Thanks Madires and Mark Heinz for this amazing tool!
My 4 year old computer suffered from occasionally blue screen and I just used this meter and found several caps near the memory slots have way higher ESR than normal. I changed these bugs and now my computer is running strong again.
I guess my unit from Ebay is still running an old firmware. I am waiting for my ISP programmer to update it and I really expect to test the new on-circuit ESR function.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 02, 2014, 10:35:01 pm
Sure! Any documentation on the input stage? Need to sort through the Eagle library for that encoder but I can find some space on board.

Please download http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/) and see ttester.pdf.

Should I use this package for the rotary encoder? ALPS_EC12E_SW You can find it in the Eagle library.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 03, 2014, 11:55:33 am
thank you madires, and Mark Heinz for this cool tester, I am still waiting my lcd come, and I am really new to this programming stuff. I hope I could make this, or maybe I would try basic program first to get familiar with this microcontroller things. once again thank you for you all make this cool stuff.

You're welcome! The ATmega is a nice microcontroller for starters. My first one was the venerable 68HC11 and I still got the development board. BTW, his name is Karl-Heinz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 03, 2014, 12:08:17 pm
Should I use this package for the rotary encoder? ALPS_EC12E_SW You can find it in the Eagle library.

That one is fine (got some EC11 or 12 in my drawer ;) ).
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 03, 2014, 10:29:15 pm
I made my version of the project based on the ttester_eng110k.pdf schematic. It implements the 2.5 voltage reference, external crystal, TVS diode and relay protection of the inputs, but not the zener measurement. I'm able to get it to work with the 1.10k firmware with the relay removed. However, with the 1.12m version of the firmware, I either get no component found or some very large capacitance when no capacitor is attached. I'm assuming I haven't built the firmware correctly--any hints on what I need to adjust in the config.h or makefile? (Attached are the makefile and config.h I'm using when trying to build the 1.12m firware.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on July 03, 2014, 11:14:10 pm
A nice work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 04, 2014, 12:46:02 pm
Thanks!

Here are a couple more images of the layout.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 04, 2014, 01:48:19 pm
I made my version of the project based on the ttester_eng110k.pdf schematic. It implements the 2.5 voltage reference, external crystal, TVS diode and relay protection of the inputs, but not the zener measurement. I'm able to get it to work with the 1.10k firmware with the relay removed. However, with the 1.12m version of the firmware, I either get no component found or some very large capacitance when no capacitor is attached. I'm assuming I haven't built the firmware correctly--any hints on what I need to adjust in the config.h or makefile? (Attached are the makefile and config.h I'm using when trying to build the 1.12m firware.)

Which frequency does your crystal have? Based on the Makefile it's 16MHz. I haven't tested the m-firmware with the new input protection IC and TVS yet (lack of prototype with that IC). So it could be possible that it may cause some trouble, but mostly the crystal frequency and the fuse settings are misset. Regarding the relay problem I'd suggest to try increasing the delay time. The boards with relay protection I got use a quite small relay (Karl-Heinz got the same). A large relay might simply need some more time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 04, 2014, 02:44:51 pm
Which frequency does your crystal have? Based on the Makefile it's 16MHz. I haven't tested the m-firmware with the new input protection IC and TVS yet (lack of prototype with that IC). So it could be possible that it may cause some trouble, but mostly the crystal frequency and the fuse settings are misset. Regarding the relay problem I'd suggest to try increasing the delay time. The boards with relay protection I got use a quite small relay (Karl-Heinz got the same). A large relay might simply need some more time.
Thanks to Karl-Heinz and you for all your work on this project--it's a very nice contribution.

About my build:
* It's a 16 Mhz crystal
* The fuse values are L:f7 H:d9 E:fC
  * I'm using ProgISP with a cheap ebay programmer
* I get the same behavior with and without the relay installed--if I physically remove the relay, the TPs should all be disconnected, so it should have no effect, correct?

For the K version of the firmware, I used the built in RC oscillator (because I couldn't figure out if it supported a 16Mhz crystal) and didn't see a place to specify a relay in the makefile, so I had the relay removed. The K version works as expected.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 04, 2014, 04:04:53 pm
About my build:
* It's a 16 Mhz crystal
* The fuse values are L:f7 H:d9 E:fC
  * I'm using ProgISP with a cheap ebay programmer
* I get the same behavior with and without the relay installed--if I physically remove the relay, the TPs should all be disconnected, so it should have no effect, correct?

For the K version of the firmware, I used the built in RC oscillator (because I couldn't figure out if it supported a 16Mhz crystal) and didn't see a place to specify a relay in the makefile, so I had the relay removed. The K version works as expected.

The fuse settings look fine and the missing relay shouldn't have any impact besides a small delay for the measurements. The k-firmware supports 16MHz too. I think, the next step is to check if the crystal oscillator is running. If it's not running please verify if the two caps between the crystal and ground got the correct value (18 or 22pF).
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 04, 2014, 05:09:13 pm
The fuse settings look fine and the missing relay shouldn't have any impact besides a small delay for the measurements. The k-firmware supports 16MHz too. I think, the next step is to check if the crystal oscillator is running. If it's not running please verify if the two caps between the crystal and ground got the correct value (18 or 22pF).

The crystal is oscillating (see attached capture of the waveform). I can see the tester going through the test and updating the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Wh1sper on July 04, 2014, 05:19:40 pm
Hi,
I did build one at my own with the great PCB made by Moritz A.
down side: expensive to build
plus: I have build it myself, by using the best components I could get. i.e. the high precision Reststors.
I understand the design, I have the schematics
But I bought a Chinese clone with graphic Display recently as second device.
Plus: CHEAP! and very nice build.
down side: no schematics, no precision resistors.
The measuring experience is by far not so exact as the German home build .
But for a quick qheck it is very useful.
So my thumb goes up for having 2, at least :-)
Also important is to have 2 different software versions.

Overall I like this project a lot.
Whenever one of the developers comes at my City, I own them a beer, or two :-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 04, 2014, 05:29:19 pm
The crystal is oscillating (see attached capture of the waveform). I can see the tester going through the test and updating the display.

Ok. Have you run the self adjustment? Prior to that please measure a film cap around 220nF up to 2µF three or four times. Does the tester identify resistors, diodes and transistors?
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 05, 2014, 09:46:37 pm
The crystal is oscillating (see attached capture of the waveform). I can see the tester going through the test and updating the display.

Ok. Have you run the self adjustment? Prior to that please measure a film cap around 220nF up to 2µF three or four times. Does the tester identify resistors, diodes and transistors?

It doesn't recognize any components attached. While testing, the relay chatters (rapid on/off). Using the K firmware, there are just a few clicks of the relay during testing and it reports reasonable values.

As a side note: I originally used a BC547  to control the relay, but the transistor failed. The BC547 is rated to 100 mA and the relay is rated at 80 mA, so I didn't expect a problem. I replaced it with a 2n2222 which should hopefully be sufficient.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 05, 2014, 10:12:13 pm
It doesn't recognize any components attached. While testing, the relay chatters (rapid on/off). Using the K firmware, there are just a few clicks of the relay during testing and it reports reasonable values.

That's strange! Could you please set the fuses to select the internal RC oscilllator (8MHz), recompile the m-firmware for 8MHz RC oscillator and try it again? BTW, could you also please sketch the circuit part driving the relay (PC4 and the voltage reference).
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 05, 2014, 10:13:25 pm
I've been working on this project and I managed to get a single sided pcb with 5 wire-passes on the topside.
It has the Zener diode test and frequency test. Also it includes the left-right encoder with push-button.  There's a ZIF socket, pcb banana connectors and a daughter-board for the SMD stuff. You can just connect that if needed. Also there's a protection relay for charged caps. Also I've used 2 regulators, one for the IC and one for powering the extras. There's an ICSP connector as well. There is no pot for adjusting the contrast/light on the LCD, you will have to figure out the values for those things.
I still have some work to do on it, need to match holes for LCD support so it can be fixed with spacers. I will need to move some parts around to do that. Also I need to double check the footprint of some parts, and see what's available. The LCD should clear most parts.
This is a nice diy board that can be made at home. I will post the files after I'm finished with it.
Also I want to thank Mr. Madires as he guided me through this project.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 06, 2014, 12:01:52 am
I made the holes for the LCD. I used this datasheet:
http://www.adafruit.com/datasheets/TC1602A-01T.pdf (http://www.adafruit.com/datasheets/TC1602A-01T.pdf)
Seemed like a generic 2 line LCD.
Also now there are only 4 wire-passes on the top side. Rearranged the SMD pads a bit.
Any suggestions?
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 06, 2014, 12:15:55 am
I made the holes for the LCD. I used this datasheet:
http://www.adafruit.com/datasheets/TC1602A-01T.pdf (http://www.adafruit.com/datasheets/TC1602A-01T.pdf)
Seemed like a generic 2 line LCD.
Also now there are only 4 wire-passes on the top side. Rearranged the SMD pads a bit.
Any suggestions?
Nice layout. You may want to try to re-position the programming header so it's not under the LCD. With the LCD in place, it may interfere with the header. Also, it would be nice to reprogram it without having to remove the LCD. Your TO-92 packages seem to have different sized pads--you may want to make all of them the same with the larger pad sizes. You could also probably increase the pad sizes for the film capacitors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 06, 2014, 12:18:35 am
It doesn't recognize any components attached. While testing, the relay chatters (rapid on/off). Using the K firmware, there are just a few clicks of the relay during testing and it reports reasonable values.

That's strange! Could you please set the fuses to select the internal RC oscilllator (8MHz), recompile the m-firmware for 8MHz RC oscillator and try it again? BTW, could you also please sketch the circuit part driving the relay (PC4 and the voltage reference).

I switched it to use the RC oscillator with fuses  L:e2 H:d9 E:fc and adjusted the makefile to use OSCILLATOR = RC, but get the same behavior. Attached is the schematic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nessatse on July 06, 2014, 10:28:29 am
I made the holes for the LCD. I used this datasheet:
http://www.adafruit.com/datasheets/TC1602A-01T.pdf (http://www.adafruit.com/datasheets/TC1602A-01T.pdf)
Seemed like a generic 2 line LCD.
Also now there are only 4 wire-passes on the top side. Rearranged the SMD pads a bit.
Any suggestions?


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 06, 2014, 11:31:29 am
I switched it to use the RC oscillator with fuses  L:e2 H:d9 E:fc and adjusted the makefile to use OSCILLATOR = RC, but get the same behavior. Attached is the schematic.

Thanks! The schematic looks fine, my prototype with the relay protection has exactly the same driver. The only difference is the input protection IC and it got a 8MHz crystal, and a smaller relay. Since you mentioned the Makefile, have you also set FREQ = 8? What puzzles me, is that there's no flapping of the relay with the k-firmware. My next idea would have been to check Vcc in case the current draw of the relay causes the issue. Both firmwares drive the relay the same way, just with a slightly different timing regarding the measurement procedure. The MCU clock shouldn't have any impact on the relay anyway. I think we're overlooking something.
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 06, 2014, 01:29:05 pm
I made the holes for the LCD. I used this datasheet:
http://www.adafruit.com/datasheets/TC1602A-01T.pdf (http://www.adafruit.com/datasheets/TC1602A-01T.pdf)
Seemed like a generic 2 line LCD.
Also now there are only 4 wire-passes on the top side. Rearranged the SMD pads a bit.
Any suggestions?
  • Your zener and frequency labels appear to switched.
  • You probably need a lot more clearance around the lcd mounting holes if you don't want screws/nuts shorting out your traces.
  • If this board is designed for home etching, I would suggest increasing your ground plane clearance a little
  • As radioFlash suggested, try increase some of your pad sizes and get the size consistent
* I used a 130 thou radius circle for the keep-out region around the LCD mounting holes. This gives just barely enough clearance for a 4-40 nut.
* I think you will have a clearance problem with the trim pot positioned under the LCD. To avoid that and allow adjustment with the LCD in place, you may wish to move the trim pot down a bit.
* The LCD has some metal tabs on the back which are bent to keep the LCD attached to the PCB. They project out about 1/10 inch. The LCD PCB will be about 430 thou above your PCB when mounted, so keep that in mind when thinking about clearance.

Attached is a photo of a 4-40 nut with the 130 tho radius keep-out region and an image of the backside of the LCD.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 09, 2014, 10:29:26 pm
I guess this is the best I could do.
It's hard as everything is tight, and as soon as I move some parts/traces I loose ground in some places and I don't want to add more wire passes. I think one could mount some non-conducting spacers on the back of the PCB for electrical isolation between the tracks and the nut. Also I think you could mount some taller spacers for the LCD but I think it should clear most of the parts.
If you wish I could post the Eagle files.
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 11, 2014, 01:05:28 am
I switched it to use the RC oscillator with fuses  L:e2 H:d9 E:fc and adjusted the makefile to use OSCILLATOR = RC, but get the same behavior. Attached is the schematic.

Thanks! The schematic looks fine, my prototype with the relay protection has exactly the same driver. The only difference is the input protection IC and it got a 8MHz crystal, and a smaller relay. Since you mentioned the Makefile, have you also set FREQ = 8? What puzzles me, is that there's no flapping of the relay with the k-firmware. My next idea would have been to check Vcc in case the current draw of the relay causes the issue. Both firmwares drive the relay the same way, just with a slightly different timing regarding the measurement procedure. The MCU clock shouldn't have any impact on the relay anyway. I think we're overlooking something.

Good news--I was able to get the M firmware working. I switched from the cheap ebay "USB ISP" programmer to a genuine Atmel AVR ISP MkII programmer. The relay is working properly and values look reasonable. I may have been using the programmer software for the cheap programmer incorrectly. Using avrdude from the makefile to program the MCU has cleared up my problems.

Does the M version of the firmware support a rotary encoder yet?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 11, 2014, 12:12:09 pm
Good news--I was able to get the M firmware working. I switched from the cheap ebay "USB ISP" programmer to a genuine Atmel AVR ISP MkII programmer. The relay is working properly and values look reasonable. I may have been using the programmer software for the cheap programmer incorrectly. Using avrdude from the makefile to program the MCU has cleared up my problems.

That's great! One thing less I have to worry about :)

Quote
Does the M version of the firmware support a rotary encoder yet?

The next version will, I'm currently adding support for rotary encoders. Reading the encoder already works nicely using an ALPS EC11, but other encoders should also be fine (you just need to set the pulses per step/detent in config.h). Right now I'm working on using the extra user input to improve the UI. When running the PWM tool you can use the encoder to increase or decrease the PWM ratio in steps of 1% additional to the 5% steps of the push button. And I also have to get more encoders for testing the algorithm for reading the encoder signals, some crappy ones ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 12, 2014, 09:18:16 pm
Just a quick update, you'll find 1.13m in the SVN now. And I'd appreciate any feedback on the rotary encoder's usability.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 16, 2014, 09:05:12 pm
 :) Hello everyone! Built this tester, works great, huge thanks to authors  :-+ Currently I use Mega8 with v1.04k and ordered Mega328, but encountered a problem - no compiled software available. I need version from Karl Heinz because i need to measure inductance. Can someone please post link to compiled version v1.11k ?  ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 16, 2014, 09:48:29 pm
:) Hello everyone! Built this tester, works great, huge thanks to authors  :-+ Currently I use Mega8 with v1.04k and ordered Mega328, but encountered a problem - no compiled software available. I need version from Karl Heinz because i need to measure inductance. Can someone please post link to compiled version v1.11k ?  ::)

IIRC, the inductance measurement requires an ATmega with 16kB flash or more.
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on July 16, 2014, 11:26:18 pm
:) Hello everyone! Built this tester, works great, huge thanks to authors  :-+ Currently I use Mega8 with v1.04k and ordered Mega328, but encountered a problem - no compiled software available. I need version from Karl Heinz because i need to measure inductance. Can someone please post link to compiled version v1.11k ?  ::)

IIRC, the inductance measurement requires an ATmega with 16kB flash or more.

Hence why he ordered a mega328?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 16, 2014, 11:41:46 pm
Hence why he ordered a mega328?

Got it. :) It's http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/) for the standard circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 17, 2014, 07:24:05 am
Thanks  ;) Now I can test this great gadget
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 20, 2014, 07:49:26 pm
Hi guys, decided to show it working. Have to say, it works like charm, considering that it's built in such a rude way  ;D I discovered interesting little glitch - you test diode, it displays it OK (symbol), but when you reverse connection, symbol gets messed up ??? Does someone have similar problem? I think it's connected either with LCD or EEPROM
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 20, 2014, 08:34:27 pm
Hi guys, decided to show it working. Have to say, it works like charm, considering that it's built in such a rude way  ;D I discovered interesting little glitch - you test diode, it displays it OK (symbol), but when you reverse connection, symbol gets messed up ??? Does someone have similar problem? I think it's connected either with LCD or EEPROM

Cheap Chinese LCD? :) I'd think something went wrong while compiling or flashing the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 20, 2014, 09:53:06 pm

Hi guys, decided to show it working. Have to say, it works like charm, considering that it's built in such a rude way  ;D I discovered interesting little glitch - you test diode, it displays it OK (symbol), but when you reverse connection, symbol gets messed up ??? Does someone have similar problem? I think it's connected either with LCD or EEPROM

I noticed the glitched diode icon with the latest version of the K version of the firmware. I didn't have the issue with earlier versions.


Sent from my iPhone using Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 21, 2014, 04:54:16 am
Cheap Chinese LCD? :) I'd think something went wrong while compiling or flashing the firmware.
Yeah, I bought it for around 3$  :D

I noticed the glitched diode icon with the latest version of the K version of the firmware. I didn't have the issue with earlier versions.
Sent from my iPhone using Tapatalk
Thanks for response, this means that I programmed MCU right
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on July 21, 2014, 05:29:35 pm
Maybe you have mentioned it several times... What is the method used for measuring inductance, capacitance? I am thinking an LC meter spin-off.

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 21, 2014, 08:30:17 pm
I noticed the glitched diode icon with the latest version of the K version of the firmware. I didn't have the issue with earlier versions.
Sent from my iPhone using Tapatalk
Thanks for response, this means that I programmed MCU right

Ok, I've reported the issue to Karl-Heinz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 21, 2014, 08:40:16 pm
Maybe you have mentioned it several times... What is the method used for measuring inductance, capacitance? I am thinking an LC meter spin-off.

I'd go for the frequency based solution (LC oscillator) for higher accuracy and a larger measurement range. The Transistor Tester uses:
- U_c(t) = U_in * (1 - e^(-t/RC)) for capacitance
- i_L(t) = I_0 * (1 - e^(-t R / L)) for inductance (limited by the max. test current supported)
Title: Re: $20 LCR ESR Transistor checker project
Post by: kubi48 on July 21, 2014, 09:48:56 pm
Hi guys, decided to show it working. Have to say, it works like charm, considering that it's built in such a rude way  ;D I discovered interesting little glitch - you test diode, it displays it OK (symbol), but when you reverse connection, symbol gets messed up ??? Does someone have similar problem? I think it's connected either with LCD or EEPROM

I could not verify this effect with my hardware and the developer version 1.11k :-[. Probably you can send the .hex and .eep together with your Makefile to my Email address.
You can find the Email address at the front page of my PDF documentation. Usually the actual versions for the ATmega328 don't use the EEPROM for text and
fix table data because the USE_EEPROM option is deactivated in the Makefile. Only calibration data are hold in the EEPROM. So you need only load the .hex data to the flash memory. The EEPROM is initilized automatically, if no valid data are found.
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 21, 2014, 11:41:23 pm
Hi guys, decided to show it working. Have to say, it works like charm, considering that it's built in such a rude way  ;D I discovered interesting little glitch - you test diode, it displays it OK (symbol), but when you reverse connection, symbol gets messed up ??? Does someone have similar problem? I think it's connected either with LCD or EEPROM

I could not verify this effect with my hardware and the developer version 1.11k :-[. Probably you can send the .hex and .eep together with your Makefile to my Email address.
You can find the Email address at the front page of my PDF documentation. Usually the actual versions for the ATmega328 don't use the EEPROM for text and
fix table data because the USE_EEPROM option is deactivated in the Makefile. Only calibration data are hold in the EEPROM. So you need only load the .hex data to the flash memory. The EEPROM is initilized automatically, if no valid data are found.

The odd thing is that it's only the diode symbol, and only the one that's supposed to point to the right. Also, I noticed that the glitch isn't always the same. Below is a photo of the tester with a dual diode device. I will email you a copy of the hex file. I use "make upload" and avrdude to upload the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on July 21, 2014, 11:44:08 pm
Try other firmware version. I think I saw this problem a few months ago. But after replacing firmware it never appeared again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 23, 2014, 01:35:51 am
Karl-Heinz has fixed the diode symbol issue and the fix is out in the repository. Thanks!

http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on July 23, 2014, 08:58:51 am
What version contains LCR and ESR? m or k?

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 23, 2014, 01:23:43 pm
What version contains LCR and ESR? m or k?

Both, also in-circuit ESR.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on July 25, 2014, 09:52:48 pm
I finished my component tester. The varnish is not perfect, but I got it for free.
Finished Universal component avr tester with ATmega328 (https://www.youtube.com/watch?v=4lVIVKr36iM#)
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on July 26, 2014, 08:40:10 am
You really went ape shit on this one. Thanks for sharing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 26, 2014, 12:27:06 pm
I finished my component tester. The varnish is not perfect, but I got it for free.

Nice rugged DIY design!  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on July 26, 2014, 07:03:37 pm
I like the credit for the firmware -- nice touch!
Title: Re: $20 LCR ESR Transistor checker project
Post by: SeanB on July 26, 2014, 07:16:35 pm
I like that repurposed case you used. Even nicer is the 2 power input sockets so almost any power brick can be used as well irrespective of centre pin thickness.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on July 26, 2014, 08:39:13 pm
In fact the metal case was never used before. A friend gave me that. It can be 10 years old or so.
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on July 27, 2014, 08:44:51 am
Will you post a bit more detail of your work aka pics of its guts?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on July 27, 2014, 06:51:35 pm
Some photos are included in the beginning of this video.
Universal component avr tester with ATmega328 (https://www.youtube.com/watch?v=NCSb3vqkbqA#)
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on July 27, 2014, 11:18:15 pm
Some photos are included in the beginning of this video.

A very nice job. I'm jealous and will have to seriously consider an ATmega328 version for myself.

One very minor little error I noticed: Correct spelling is "clamp the 3 leads together". Something for Karl to fix in the next build, I suspect.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nickds1 on July 28, 2014, 04:28:43 pm
On the subject of typographical corrections, in the UK (and I suspect most native-English countries), we use "V" rather then "U" for voltage...
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on July 28, 2014, 07:12:14 pm
On the subject of typographical corrections, in the UK (and I suspect most native-English countries), we use "V" rather then "U" for voltage...

Good thing we use the same number symbols.  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 28, 2014, 08:34:02 pm
I could not verify this effect with my hardware and the developer version 1.11k :-[. Probably you can send the .hex and .eep together with your Makefile to my Email address.
You can find the Email address at the front page of my PDF documentation. Usually the actual versions for the ATmega328 don't use the EEPROM for text and
fix table data because the USE_EEPROM option is deactivated in the Makefile. Only calibration data are hold in the EEPROM. So you need only load the .hex data to the flash memory. The EEPROM is initilized automatically, if no valid data are found.
Hi, I used already compiled version (so I don't have a Makefile), link you can find in post #573. I used avrdude GUI (BitBurner  :-+) to write the software, manually - flash then EEPROM then fuses  8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on July 28, 2014, 08:38:53 pm
On the subject of typographical corrections, in the UK (and I suspect most native-English countries), we use "V" rather then "U" for voltage...

I had to watch that a second time. For anyone else who missed that the first time: He uses V for the results, but Uf for "forward voltage".
Title: Re: $20 LCR ESR Transistor checker project
Post by: hdlg_zhangyu on July 29, 2014, 03:44:22 am
Hi Madires,
I had a problem after updated the firmware with the most recent mega328_st7565 version in the trunk with my eBay ESR meter shown in #510.
While the meter still can be turned on/off after flashing the firmware, there is no display. I set the LCD_ST7565_RESISTOR_RATIO = 7,  and then i was able to see some faint display. I am wondering what parameters in the makefile should be set to make it working properly?

I used WinAVR-20100110 with an USBasp from ebay to updated to the newest firmware.

Thanks and appreciate your help!
I am new here and also a newbie for electronics. I got mine today from ebay. It is with Atmel Mega328p AU chip, it impressed me with all SMD components and even with a Tantalum capacitor!
However, they failed to acknowledge Karl-Heinz K"ubbeler, madires and everyone else who contributed to the firmware design.

The seller claimed it is 2014 "latest" version. However when started the program, it showed:
"Transistor Tester V2.1". Wondering what exactly firmware it is running.

ALso, I am planning to upgrade the firmware anyway to the newest version using the ISP port, I am actually wondering what version of LCD should I use? Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 29, 2014, 05:42:07 pm
Karl-Heinz has fixed the diode symbol issue and the fix is out in the repository. Thanks!

http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)
Hi guys, I have a problem here with fixed software. I push a button it says battery voltage and vcc, seems allright, but it lasts for around 5 sec. then it displays "Cell!" (see attachments), tried a new battery, no luck  :-BROKE
Title: Re: $20 LCR ESR Transistor checker project
Post by: moemoe on July 29, 2014, 05:54:02 pm
it lasts for around 5 sec. then it displays "Cell!" (see attachments), tried a new battery, no luck  :-BROKE

You probably need to adjust the Makefile parameters for the voltage divider built onto your board (+protection diode loss).
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 29, 2014, 06:18:59 pm
You probably need to adjust the Makefile parameters for the voltage divider built onto your board (+protection diode loss).
Sadly enough, I probably can't do that because I'm pretty  |O on this kind of stuff. I have 7805 on board (you want to say in Makefile a LDO regulator is specified?) + I did not installed protection diode  :-[
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 29, 2014, 06:40:46 pm
You probably need to adjust the Makefile parameters for the voltage divider built onto your board (+protection diode loss).
You meant this section "# Voltage divider for battery voltage measurement  10k / 3.3k = 133/33
#CFLAGS += -DBAT_NUMERATOR=133
#CFLAGS += -DBAT_DENOMINATOR=33
# Voltage divider for the external zener voltage measurement 180k / 20k = 10/1
#CFLAGS += -DEXT_NUMERATOR=10
#CFLAGS += -DEXT_DENOMINATOR=1" ?
Also I found this interesting section: "# The CAP_EMPTY_LEVEL  defines the empty voltage level for capacitors in mV.
# Choose a higher value, if your Tester reports "Cell!" by unloading capacitors.
CFLAGS += -DCAP_EMPTY_LEVEL=4"
More of it, I don't have needed software to compile it
P.S. Sorry for flooding, if you can I'll prefer to PM you
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 29, 2014, 06:51:52 pm
While the meter still can be turned on/off after flashing the firmware, there is no display. I set the LCD_ST7565_RESISTOR_RATIO = 7,  and then i was able to see some faint display. I am wondering what parameters in the makefile should be set to make it working properly?

That value selects the resistor divider of the module's internal voltage regulator. For most ST7565 displays 4 or 7 work fine but you could also try other values from 0 up to 7.
Title: Re: $20 LCR ESR Transistor checker project
Post by: KK on July 29, 2014, 08:52:54 pm
Bought this one with zener measurement. They say it has a atmega168 but the one sent to me had an atmega328.

I soldered pins into the icsp pads and updated the software to the latest trunk. The protection fuses weren't set but it came with an older version, I believe it was 1.08k of firmware.

The LCD is smaller than expected, and the backlight and readability are just ok.

But, it does work well.

http://www.ebay.com/itm/Transistor-Tester-Capacitor-ESR-Inductance-Resistor-Meter-Mosfet-Diode-Battery-/121346078072 (http://www.ebay.com/itm/Transistor-Tester-Capacitor-ESR-Inductance-Resistor-Meter-Mosfet-Diode-Battery-/121346078072)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hdlg_zhangyu on July 29, 2014, 11:43:44 pm
I tried all values and seems only LCD_ST7565_RESISTOR_RATIO = 7 gave me a faint display, with other values, there is no display at all.
Is there anything else i should look at?
Thanks.

While the meter still can be turned on/off after flashing the firmware, there is no display. I set the LCD_ST7565_RESISTOR_RATIO = 7,  and then i was able to see some faint display. I am wondering what parameters in the makefile should be set to make it working properly?

That value selects the resistor divider of the module's internal voltage regulator. For most ST7565 displays 4 or 7 work fine but you could also try other values from 0 up to 7.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 30, 2014, 05:14:16 pm
Got it working again! Reason is jumper on the solder side, when I pushed IC in place pin poked jumper through, effectively connecting pin 25 of AtMega328 to anode of backlight LED  :o  Big thanks to Karl Heinz, no more issues with diode symbol & double diodes  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 30, 2014, 06:13:52 pm
I tried all values and seems only LCD_ST7565_RESISTOR_RATIO = 7 gave me a faint display, with other values, there is no display at all.
Is there anything else i should look at?

I think the next step is to identify the LCD module and to get the datasheet. Maybe it needs some additional initialization.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 30, 2014, 09:18:24 pm
Excuse me please, but can someone show me where I can find full schematic (with ability to measure frequency). All I know - the pin 6 of the AtMega is the input  :-[
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on July 31, 2014, 12:03:26 am
Excuse me please, but can someone show me where I can find full schematic (with ability to measure frequency). All I know - the pin 6 of the AtMega is the input  :-[

http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/)

click on link to download the "GNU tarball". You'll need the GNU tools tar and gzip or something like 7-Zip to extract the files. Look at the file ttester_eng110k.pdf.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dentaku on July 31, 2014, 01:49:04 am
Has anyone done a video showing the self-test/calibration process for my MK-168 Transistor Tester M168_V2.20. I see lots of videos about these things but I'm not sure if the Calibration process has been demoed.
section 3.3 Selftest and Calibration in the .PDF explains it a bit - http://www.avrtester.tode.cz/upload/ttester_en.pdf (http://www.avrtester.tode.cz/upload/ttester_en.pdf) - but I'd like to see how it works by watching someone doing it.

The documentation mentions disconnecting the leads for a certain test and only connecting a cap after a certain prompt so I don't want to do it wrong.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on July 31, 2014, 05:07:49 am
http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/)
click on link to download the "GNU tarball". You'll need the GNU tools tar and gzip or something like 7-Zip to extract the files. Look at the file ttester_eng110k.pdf.
Thanks a lot, I didn't knew that this directory is existing  ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 31, 2014, 01:14:19 pm
The documentation mentions disconnecting the leads for a certain test and only connecting a cap after a certain prompt so I don't want to do it wrong.

It's pretty simple. Short circuit the three probe pins/leads and start the calibration (actually adjustment). After a few tests you'll be asked to remove the short circuit and some more tests are run. Then the tester displays the cap symbol and you connect a cap (film cap 220nF - 1µF recommended) to probes #1 and #3. That's the procedure for the k-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on July 31, 2014, 01:26:06 pm
The main difference between the k and m firmwares is that the k-firmware includes support for ESR measurement and the m-firmware has a simple menu system and a PWM tool.

Is the above statement still valid?

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dentaku on July 31, 2014, 02:04:41 pm
The documentation mentions disconnecting the leads for a certain test and only connecting a cap after a certain prompt so I don't want to do it wrong.

It's pretty simple. Short circuit the three probe pins/leads and start the calibration (actually adjustment). After a few tests you'll be asked to remove the short circuit and some more tests are run. Then the tester displays the cap symbol and you connect a cap (film cap 220nF - 1µF recommended) to probes #1 and #3. That's the procedure for the k-firmware.

OK, seems simple enough.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dentaku on July 31, 2014, 02:51:18 pm
The documentation mentions disconnecting the leads for a certain test and only connecting a cap after a certain prompt so I don't want to do it wrong.

It's pretty simple. Short circuit the three probe pins/leads and start the calibration (actually adjustment). After a few tests you'll be asked to remove the short circuit and some more tests are run. Then the tester displays the cap symbol and you connect a cap (film cap 220nF - 1µF recommended) to probes #1 and #3. That's the procedure for the k-firmware.

I'm not sure which firmware I have but the Version 1.11k May 27, 2014 .PDF I found says...

"A capacitor with any capacity between 100nF and 20F connected to pin 1 and pin 3 is required
for the last task of calibration. To indicate that, a capacitor symbol is shown between the pin number
1 and 3, followed by the text " >100nF". You should connect the capacitor not before this text is
shown. With this capacitor the o set voltage of the analog comparator will be compensated for better
measurement of capacity values. Additionally the gain for ADC measurements using the internal
reference voltage will be adjusted too with the same capacitor for better resistor measurement results
with the AUTOSCALE ADC option. If the menu option is selected for the tester and the selftest is
not started as menu function, the calibration with the external capacitor is only done for the rst
time calibration. The calibration with the external capacitor can be repeated with a selftest call as
menu selection.
The zero o set for the ESR measurement will be preset with the option ESR ZERO in the
Make le. With every self test the ESR zero values for all three pin combinations are determined.
The solution for the ESR measurement is also used to get the values of resistors below 10 with a resolution of 0:01."
Title: Re: $20 LCR ESR Transistor checker project
Post by: robimarko on July 31, 2014, 07:33:27 pm
Hi,
finally spare amtega 328 arrived,where can I find compiled 1.11k firmware ready for flashing?
Tried to find it myself but no luck so far
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 31, 2014, 08:57:20 pm
The main difference between the k and m firmwares is that the k-firmware includes support for ESR measurement and the m-firmware has a simple menu system and a PWM tool.

Is the above statement still valid?

No, the current major differences are a frequency counter and support of ST7565 based LCD modules (k-firmware). The next m-firmware version will include the frequency counter too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 31, 2014, 09:01:07 pm
Hi,
finally spare amtega 328 arrived,where can I find compiled 1.11k firmware ready for flashing?
Tried to find it myself but no luck so far

Please see http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/) or one of the other mega328 subdirectories for different hardware setups.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 31, 2014, 09:06:56 pm
I'm not sure which firmware I have but the Version 1.11k May 27, 2014 .PDF I found says...

That's the long explanation ;) I'm pretty sure that your clone runs the k-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dentaku on July 31, 2014, 10:31:45 pm
I'm not sure which firmware I have but the Version 1.11k May 27, 2014 .PDF I found says...

That's the long explanation ;) I'm pretty sure that your clone runs the k-firmware.

I just connected all three mini-grabbers together and it's firmware 1.10K

I went through all 7 tests and used one of those 200nF X2 caps. I tested some caps I already tried out this morning and the ESR readings are much lower now.
One that was 0.36ohm this morning is now 0.05ohm.

Next I ran the seven tests again but this time I used a 10uF Nichicon electrolytic.
I think I'm maybe getting more realistic numbers now. A 224uf 100V cap that measured Vloss= 1.3%, ESR=0.7ohm this morning now measures Vloss= 1.4%, ESR=0.4ohm
Title: Re: $20 LCR ESR Transistor checker project
Post by: ion on August 01, 2014, 05:15:37 pm
I just got one of these testers and tried to update the firmware using these files:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/)

I successfully flashed the .hex and .eep files using avrdude, but the tester doesn't working any more.  The LCD just displays solid blocks for the first row.  Did I use the right files for this tester?:

http://www.ebay.com/itm/2014-Atmega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-/181442767546 (http://www.ebay.com/itm/2014-Atmega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-/181442767546)
(note: the IC is actually a TQFP 328P)

I wasn't too worried as I had made a backup of the original firmware before updating, but when I tried to restore these avrdude wouldn't recognise the format.  I'm attaching the files and would appreciate any advice on what is wrong with them.


Also, I tried to use the makefile through WinAVR but I kept getting an error.  Does the makefile work on the .hex/.eep files linked above or do I need to download some other files?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 01, 2014, 09:12:45 pm
I went through all 7 tests and used one of those 200nF X2 caps. I tested some caps I already tried out this morning and the ESR readings are much lower now.
One that was 0.36ohm this morning is now 0.05ohm.

Next I ran the seven tests again but this time I used a 10uF Nichicon electrolytic.
I think I'm maybe getting more realistic numbers now. A 224uf 100V cap that measured Vloss= 1.3%, ESR=0.7ohm this morning now measures Vloss= 1.4%, ESR=0.4ohm

Have you noticed that the difference is about 0.3 Ohms for both measurements? The self-adjustment has measured a resistance of 0.15 Ohms for the probe leads (2 in series = 0.3 Ohms) and the tester uses that offset to auto-zero any resistance measurement. The cap is used to determine the offset of the internal bandgap voltage reference and the offset of the analog comparator. It's purpose is to hold a voltage for a few ms. The type isn't important, as long as the cap is able to keep the voltage constant (low internal losses).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 01, 2014, 09:30:59 pm
I successfully flashed the .hex and .eep files using avrdude, but the tester doesn't working any more.  The LCD just displays solid blocks for the first row.  Did I use the right files for this tester?:

Yes, those are the correct files! The most common issue is a wrong setting for the ISP programmer. In a few cases additional bypass caps were needed (please see ttester.pdf in the documentation sub-folder).

Quote
Also, I tried to use the makefile through WinAVR but I kept getting an error.  Does the makefile work on the .hex/.eep files linked above or do I need to download some other files?

You need the complete source code in the "trunk" directory.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ion on August 01, 2014, 11:06:37 pm
I haven't done much programming of micros using the command line so I always end up using the same settings that worked in the past.  Is there anything wrong with this command?

Code: [Select]
avrdude -c arduino -C ../etc/avrdude.conf -p atmega328p -P com6 -b19200 -U eeprom:w:TransistorTester.eep -U flash:w:TransistorTester.hex

Both the flash and eeprom say verified after they're written.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ion on August 02, 2014, 11:17:53 am
... In a few cases additional bypass caps were needed (please see ttester.pdf in the documentation sub-folder).

I added the bypass caps, similar to the picture in this post: https://www.eevblog.com/forum/testgear/14399/msg221946/#msg221946 (https://www.eevblog.com/forum/testgear/14399/msg221946/#msg221946)

Still no luck - when I press the button the LCD light up with solid blocks on the first row.  I does go off when I let go of the button now, but that has to do with the firmware or fuses as I noticed the change before adding the caps.

I managed to load the backup flash and eeprom data by specifying it as raw data, but I'm not surprised it didn't work as I downloaded it as hex.  I still can't understand why it won't upload it in the same format as I read it from the chip.

I tried compiling both the k- and m-firmware.  They don't give me any errors writing to the micro but it still won't work.

Anyone knows what else it could be?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 02, 2014, 02:44:17 pm
I haven't done much programming of micros using the command line so I always end up using the same settings that worked in the past.  Is there anything wrong with this command?

Code: [Select]
avrdude -c arduino -C ../etc/avrdude.conf -p atmega328p -P com6 -b19200 -U eeprom:w:TransistorTester.eep -U flash:w:TransistorTester.hex

Both the flash and eeprom say verified after they're written.

Seems to be fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 02, 2014, 03:00:34 pm
Still no luck - when I press the button the LCD light up with solid blocks on the first row.  I does go off when I let go of the button now, but that has to do with the firmware or fuses as I noticed the change before adding the caps.

Anyone knows what else it could be?

Another idea would be to change the BOD setting in the e-fuse. The default setting of the Makefile is 0xfc (4.3V). Please set the e-fuse to 0xfd (2.7V) and try again. Especially with some hardware options the supply voltage might not rise fast enough for the MCU and the MCU will detect that as a brown-out and resets (and keeps doing that as long as you press the push button).
Title: Re: $20 LCR ESR Transistor checker project
Post by: ion on August 02, 2014, 08:07:52 pm
Another idea would be to change the BOD setting in the e-fuse. The default setting of the Makefile is 0xfc (4.3V). Please set the e-fuse to 0xfd (2.7V) and try again. Especially with some hardware options the supply voltage might not rise fast enough for the MCU and the MCU will detect that as a brown-out and resets (and keeps doing that as long as you press the push button).

Just tried that, still doesn't work.  0xfd gets changed to 0x5 which I believe is the same setting (for that matter 0xfc gets changed to 0x4).  The e-fuse setting it came with was 0x7 (BOD disabled?), and that doesn't work either.

The only difference I've noticed is that with BOD settings below 4.3V, the LCD and LED stay on after I let go of the button.  They do time out eventually (~70s).

Edit:  Just noticed the LED only turns on after I let go of the button and turns off again if I hold the button down.  Not sure if it's supposed to do this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 02, 2014, 08:51:07 pm
The only difference I've noticed is that with BOD settings below 4.3V, the LCD and LED stay on after I let go of the button.  They do time out eventually (~70s).

At least some progress ;) That means that the MCU is running and after a few test cycles the tester powers off as intended. The next step is to check the LCD module. Contrast? Which pin of the LCD is connected to which pin of the ATmega? If you got another LCD module, you could try that one.

Quote
Edit:  Just noticed the LED only turns on after I let go of the button and turns off again if I hold the button down.  Not sure if it's supposed to do this.

That's ok, it's designed that way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ion on August 02, 2014, 10:40:08 pm
... Which pin of the LCD is connected to which pin of the ATmega?

I think I've spotted the problem - most of the pins don't match the schematic:

RS - PD7
E - PD5
D4 - PD4
D5 - PD3
D6 - PD2
D7 - PD1

The do seem to match the pinout for the stripboard version though!  I'll try to load that version in the morning (I've learned not to work on electronics when I'm tired!).  Loading the wrong version shouldn't have caused any damage right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: nessatse on August 03, 2014, 10:08:30 am
Just completed my own version (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg470219/#msg470219 (https://www.eevblog.com/forum/testgear/)), and I must congratulate Karl-Heinz and Markus on this magnificent project.  An example of true engineering.  :-+

I have however picked up a small problem with the 1.13m version.  It seems that resistors in the range between approximately 1.5k and 3k are incorrectly identified as double diodes.  I verified this using a 4k7 trimpot and stepping through its range.  It does not matter which pins I use, at about 1.5k it starts identifying as a double diode almost all the way to about 3k.  I loaded the 'k' version of the software and it works perfectly throughout the range.

I cannot discount the possibility that there is something wrong with my hardware, but I think the likelihood is low, since it works perfectly for every other component I have thrown at it so far.

I have started looking at the source to try and figure out where it is going wrong, but that may take a while.  Any suggestions?


Edit: Added image.  Two diodes with cathodes going to the same pin?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 03, 2014, 11:12:43 am
The do seem to match the pinout for the stripboard version though!  I'll try to load that version in the morning (I've learned not to work on electronics when I'm tired!).  Loading the wrong version shouldn't have caused any damage right?

The ATmega should have survived the different pinout. The only issue would be the test button, if the ATmega's pin is set to high output and is short circuited by the BJT when the test button is pressed. But the ATmega is able to take some pain ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ion on August 03, 2014, 12:31:23 pm
The do seem to match the pinout for the stripboard version though!  I'll try to load that version in the morning (I've learned not to work on electronics when I'm tired!).  Loading the wrong version shouldn't have caused any damage right?

The ATmega should have survived the different pinout. The only issue would be the test button, if the ATmega's pin is set to high output and is short circuited by the BJT when the test button is pressed. But the ATmega is able to take some pain ;)

Well, it did survive.  Just loaded the stripboard version of the latest firmware and it's working great (https://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif)

Thanks for all the help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 03, 2014, 02:22:10 pm
I have however picked up a small problem with the 1.13m version.  It seems that resistors in the range between approximately 1.5k and 3k are incorrectly identified as double diodes.  I verified this using a 4k7 trimpot and stepping through its range.  It does not matter which pins I use, at about 1.5k it starts identifying as a double diode almost all the way to about 3k.  I loaded the 'k' version of the software and it works perfectly throughout the range.

I can reproduce the problem and will look into it. Thanks for reporting!

Quote
I have started looking at the source to try and figure out where it is going wrong, but that may take a while.  Any suggestions?

It's the diode detection.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hdlg_zhangyu on August 03, 2014, 09:32:30 pm
Hi Madires,
Display problem solved.
I don't know what changes was brought to the most recent mega328_st7565 trunk version, i modified the makefile:
CD_ST7565_RESISTOR_RATIO = 5
CFLAGS += -DFONT_6X8
I don't know why CFLAGS += -DFONT_8X16 always gave me an: "avrdude: ERROR: address 0x8010 out of range at line 2049 of ./TransistorTester.hex" message

and the display is working properly now. However, there's a minor problem with the display, the left side character is only partially displayed, is there anyway to fix it?

Thanks for your help!


I tried all values and seems only LCD_ST7565_RESISTOR_RATIO = 7 gave me a faint display, with other values, there is no display at all.
Is there anything else i should look at?
Thanks.

While the meter still can be turned on/off after flashing the firmware, there is no display. I set the LCD_ST7565_RESISTOR_RATIO = 7,  and then i was able to see some faint display. I am wondering what parameters in the makefile should be set to make it working properly?

That value selects the resistor divider of the module's internal voltage regulator. For most ST7565 displays 4 or 7 work fine but you could also try other values from 0 up to 7.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 03, 2014, 10:24:51 pm
I have however picked up a small problem with the 1.13m version.  It seems that resistors in the range between approximately 1.5k and 3k are incorrectly identified as double diodes.  I verified this using a 4k7 trimpot and stepping through its range.  It does not matter which pins I use, at about 1.5k it starts identifying as a double diode almost all the way to about 3k.  I loaded the 'k' version of the software and it works perfectly throughout the range.

Please edit semi.c and change in function CheckDiode()

Code: [Select]
    U1_Zero /= 50;            /* 2% */
    U1_Rh += U1_Zero;         /* 102% */

into

Code: [Select]
    U1_Zero /= 10;            /* 10% */
    U1_Rh += U1_Zero;         /* 110% */

5% (/= 20) might be also sufficient.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 03, 2014, 10:52:39 pm
I don't know why CFLAGS += -DFONT_8X16 always gave me an: "avrdude: ERROR: address 0x8010 out of range at line 2049 of ./TransistorTester.hex" message

The ATmega328 has only 32k flash ;)

Quote
and the display is working properly now. However, there's a minor problem with the display, the left side character is only partially displayed, is there anyway to fix it?

That's strange! Seems to be related to the font based positioning. Could you please delete all object files and recompile the firmware. Maybe something got stuck when you tried the 8x16 font.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hdlg_zhangyu on August 03, 2014, 11:55:56 pm
No luck recompiled the files   |O
 
I don't know why CFLAGS += -DFONT_8X16 always gave me an: "avrdude: ERROR: address 0x8010 out of range at line 2049 of ./TransistorTester.hex" message

The ATmega328 has only 32k flash ;)

Quote
and the display is working properly now. However, there's a minor problem with the display, the left side character is only partially displayed, is there anyway to fix it?

That's strange! Seems to be related to the font based positioning. Could you please delete all object files and recompile the firmware. Maybe something got stuck when you tried the 8x16 font.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hdlg_zhangyu on August 04, 2014, 12:18:15 am
modified the lcd-routines.c
set the cursor at each line start with (x,1), and the problem is fixed.
Will this change have any negative effects? e.g. alter the display at end of each line?



No luck recompiled the files   |O
 
I don't know why CFLAGS += -DFONT_8X16 always gave me an: "avrdude: ERROR: address 0x8010 out of range at line 2049 of ./TransistorTester.hex" message

The ATmega328 has only 32k flash ;)

Quote
and the display is working properly now. However, there's a minor problem with the display, the left side character is only partially displayed, is there anyway to fix it?

That's strange! Seems to be related to the font based positioning. Could you please delete all object files and recompile the firmware. Maybe something got stuck when you tried the 8x16 font.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 04, 2014, 04:17:03 pm
modified the lcd-routines.c
set the cursor at each line start with (x,1), and the problem is fixed.
Will this change have any negative effects? e.g. alter the display at end of each line?

Great! I don't think it will cause any new problems.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nessatse on August 04, 2014, 05:39:48 pm


Quote from: nessatse on Yesterday at 11:08:30 (https://www.eevblog.com/forum/index.php?topic=14399.msg490259#msg490259)
I have however picked up a small problem with the 1.13m version.  It seems that resistors in the range between approximately 1.5k and 3k are incorrectly identified as double diodes.  I verified this using a 4k7 trimpot and stepping through its range.  It does not matter which pins I use, at about 1.5k it starts identifying as a double diode almost all the way to about 3k.  I loaded the 'k' version of the software and it works perfectly throughout the range.



Please edit semi.c and change in function CheckDiode()

Code: [Select] (https://www.eevblog.com/forum/javascript:void(0);)    U1_Zero /= 50;            /* 2% */
    U1_Rh += U1_Zero;         /* 102% */

into

Code: [Select] (https://www.eevblog.com/forum/javascript:void(0);)    U1_Zero /= 10;            /* 10% */
    U1_Rh += U1_Zero;         /* 110% */

5% (/= 20) might be also sufficient.


Thanks! It works with both 5% and 10%!  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: dentaku on August 04, 2014, 08:34:54 pm
I just tried to measure two 10000uF 50V Nichicon caps with my MK-168 tester (firmware 1.10K) and they both keep measure no bigger than 5986uF

Is this the limit of these testers?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 04, 2014, 08:45:01 pm
I just tried to measure two 10000uF 50V Nichicon caps with my MK-168 tester (firmware 1.10K) and they both keep measure no bigger than 5986uF

Is this the limit of these testers?

The theoretical limit is 100mF and I've tested up to 22mF successfully with several testers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dentaku on August 04, 2014, 09:12:46 pm
I just tried to measure two 10000uF 50V Nichicon caps with my MK-168 tester (firmware 1.10K) and they both keep measure no bigger than 5986uF

Is this the limit of these testers?

The theoretical limit is 100mF and I've tested up to 22mF successfully with several testers.

Yup. I think these two caps might be quite bad. They both measure way too low uF-wise and around 4ohm or more ESR.

I just tried the other capacitor test (C+ESR@TP1:3) you get when you hold down the button and I like it better for testing a bunch of caps because it just keeps testing endlessly. The big caps give me about the same numbers with that test too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dentaku on August 05, 2014, 01:03:36 pm
I just tried to measure two 10000uF 50V Nichicon caps with my MK-168 tester (firmware 1.10K) and they both keep measure no bigger than 5986uF

Is this the limit of these testers?

The theoretical limit is 100mF and I've tested up to 22mF successfully with several testers.

I just did a test and you're right, it can easily do 10mF because I connected two 4700uF caps in parallel and it reads C=10.7mF and ESR=0.04ohm

This give me more confidence that those 10000uF caps are bad. Maybe I can resurrect the Onkyo receiver I removed them from :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on August 15, 2014, 02:21:46 am
I have a question about the "Button" connection for the Zener expansion option. Should the gate of T4 be tied directly to PD7, or is there supposed to be a button switch between the two, or something else?

Attached is the schematic from the ttester.pdf manual.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 15, 2014, 07:24:53 pm
I have a question about the "Button" connection for the Zener expansion option. Should the gate of T4 be tied directly to PD7, or is there supposed to be a button switch between the two, or something else?

Yes, please connect the gate of T4 directly to PD7.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on August 18, 2014, 02:36:55 am
knowing what you all know about the testers available on e----, if you had your choice on which one to buy and it can be updated and will work, which one would you buy?
I would appreciate a particular one and not just anyone will work. I don't want to guess and get the wrong one or one that does not work or can't be updated.

Thanks
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 18, 2014, 12:56:16 pm
knowing what you all know about the testers available on e----, if you had your choice on which one to buy and it can be updated and will work, which one would you buy?
I would appreciate a particular one and not just anyone will work. I don't want to guess and get the wrong one or one that does not work or can't be updated.

Basically any clone with an ATmega328 and a standard 2x16 LCD display will work fine. If you're looking for a particular recommendation please read a few posts back and you'll find several links, pictures and comments on specific models.

PS: Firmware 1.14m was released a few days ago with some minor improvements, a fix for the resistor issue (1k5-3k) and the frequency counter option. There's also an adapter PCB (DIY-style, Eagle files) for the rotary encoder and frequeny counter input stage in the hardware sub-directory in the SVN.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on August 19, 2014, 02:58:49 am
The only thing I would recommend is that you purchase one with a DIP socketed 328.  That way you can buy a spare 328, program it up to the latest level and swap it in to test it.  If the new 328 does not work, just revert back to the old 328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlessandroAU on August 21, 2014, 07:14:47 pm
Does anyone have any experience with these variations that are popping up on ebay?

I don't really have any reference standard to compare it to but it seems to measure and identify any passive I can throw at it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: andrewwong2000 on August 21, 2014, 09:40:29 pm
Hey Alessandro

That's the "LCR T3" design.

Any chance you can read the flash and EEPROM and email to me ?

These ones use an older version of the firmware but I'm trying to figure out that display so it can be upgradeable.

That one you have has a 6pin ISP pin pad but it's reversed on the component side :)



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Title: Re: $20 LCR ESR Transistor checker project
Post by: v0yAgEr on August 23, 2014, 11:56:04 pm
Hi everyone,
Can someone please confirm that mk-168 unit is indeed m328 and supports firmware upgrades? I really want to buy one, but I want to make sure I got that covered first.
Thanks!

Chinese MK-168 Electronic Component Tester review/demo [1/2] (https://www.youtube.com/watch?v=b3dPBnYixs4#ws)
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on August 24, 2014, 01:00:27 am
Hi everyone,
Can someone please confirm that mk-168 unit is indeed m328 and supports firmware upgrades? I really want to buy one, but I want to make sure I got that covered first.
Thanks!

Chinese MK-168 Electronic Component Tester review/demo [1/2] (https://www.youtube.com/watch?v=b3dPBnYixs4#ws)

The video doesn't show what's under the LCD, so you can't tell from the video alone. The board also seems to be single sided--most singled sided versions of the board don't seem to have a programming header. Since it has "168" in the name, my guess is it uses the ATmega168 rather than Atmega328. I would look for another variant.
Title: Re: $20 LCR ESR Transistor checker project
Post by: v0yAgEr on August 24, 2014, 06:45:39 am
Hi everyone,
Can someone please confirm that mk-168 unit is indeed m328 and supports firmware upgrades? I really want to buy one, but I want to make sure I got that covered first.
Thanks!

Chinese MK-168 Electronic Component Tester review/demo [1/2] (https://www.youtube.com/watch?v=b3dPBnYixs4#ws)

The video doesn't show what's under the LCD, so you can't tell from the video alone. The board also seems to be single sided--most singled sided versions of the board don't seem to have a programming header. Since it has "168" in the name, my guess is it uses the ATmega168 rather than Atmega328. I would look for another variant.

Thanks for the reply!
If not that unit, then Im looking for something like this:
Flashable m328, and would really like to have a model with probes for in-circuit testings. Any recommendations?
Title: Re: $20 LCR ESR Transistor checker project
Post by: omgfire on August 24, 2014, 07:06:45 am
Hi everyone,
Can someone please confirm that mk-168 unit is indeed m328 and supports firmware upgrades? I really want to buy one, but I want to make sure I got that covered first.
Thanks!
https://www.eevblog.com/forum/beginners/what's-your-favorite-little-inexpensive-esr-etc-tester/msg470124/#msg470124 (https://www.eevblog.com/forum/beginners/what's-your-favorite-little-inexpensive-esr-etc-tester/msg470124/#msg470124)
Title: Re: $20 LCR ESR Transistor checker project
Post by: v0yAgEr on August 24, 2014, 10:22:24 am
Great! Ordering now...
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on August 26, 2014, 02:50:38 am
I bought a couple of these testers... the fish8840 version with the nice graphics LCD.  Yeah,  probably not as upgrade friendly as the character LCD units,  but I'm a sucker for pretty pictures (but it doesn't draw pictures for SCR's and TRIACs).  They work very well.  So far it has properly identified everything I've thrown at it (except some big SCRs and TRIACs that it can't drive the gate hard enough.  Component values measurements are in the .2% accuracy range.  All in all,  the best 20 bucks you can spend...

Both units had a problem where they would not turn on with a fresh battery installed...  the screen would just flash once and then go off.  A few of simple fixes for this...  use a used battery,  a low ohm resistor in series with the battery (2 ohms worked for me), or replace the 78L05 regulator with an LM2936 ultra low power LDO regulator... same pinouts as the 78L05 and it also drops a few mA from the operating current...  that was my ultimate solution to the problem.

The other problem is the battery voltage divider is connected permanently across the battery.  The OFF current is 180 uA...  will drain the battery in a couple of months.  I moved the input of the voltage divider resistors from the battery connection to the input of the voltage regulator (i.e. after the power-switch transistor).  This reduces the OFF current to well below 1 micro-amp.

One really useful addition to the firmware would be the ability to measure the Rds ON resistance of FETs...
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on August 28, 2014, 06:49:59 am
Great! Ordering now...

I just ordered one of these myself from Amazon after seeing the teardown. Which firmware should I use on this? There seems to be so many versions of these and the firmware, I’m a little confused. Edit: After looking around, since this uses an AT328P and standard 20x2 LCD, I guess the m328 build is what I’m after?

Another question, after watching the YouTube video you linked, this seems to show the battery voltage on startup. Is there a regulator onboard? I’d like to power this from a small LiPo battery with a tiny LiPo -> 5V boost converter. Is that battery test feature part of the “official” firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Wh1sper on August 28, 2014, 12:51:15 pm
Does anyone have any experience with these variations that are popping up on ebay?

I don't really have any reference standard to compare it to but it seems to measure and identify any passive I can throw at it.

I do own this one without case.
It measure quite well not so exact like my other selfmade one. I guess the resictors are not so high quality ones.

I wished there were some more information about the LCD Hardware .. Controller.. etc.
Downside is the software isn't open any more :-(
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on August 28, 2014, 01:19:32 pm
Downside is the software isn't open any more :-(
You mean Transistor Tester is not an open source anymore?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 28, 2014, 02:24:56 pm
Downside is the software isn't open any more :-(
You mean Transistor Tester is not an open source anymore?

No worries! The official Transistor Tester firmware (k and m version) is open source!!! Unfortunately some clone vendors modify the source and claim ownership while violating the copyright of the original authors. It doesn't make much sense to try stopping them, because that would require a lot of money for lawyers. Therefore my advice is to buy only hardware compatible clones, since those can be upgraded to the current firmware version. If you buy a clone with a modified hardware/firmware, you might never get any update from the vendor. And a self-made tester is best one anyway ;)

PS: The next m-firmware version will have a squarewave signal generator (up to 2MHz for 8MHz MCU clock) operated by the rotary encoder supporting dynamic turning velocity.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Wh1sper on August 28, 2014, 05:23:29 pm
Downside is the software isn't open any more :-(
You mean Transistor Tester is not an open source anymore?
No no, only the Chinese modifier don't publish their modifications.
That's what a meant.
What a dissipation of human brain power.
Imagine those Chinese guys (or girls?) would contribute their improvements and / or modifications.......
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on August 30, 2014, 07:20:03 am
So, my MK-168 unit came in today. The build quality is pretty nice overall; it uses an AT328P in a socket, with no footprint for an ICSP header. Looking at the board it seems to have been designed late last year. Some markings on the board: M168_V2.20, M8/168/328_9V_V2.20, 2013.10.16, EZM Electronics Studio.

The one real problem I found was C3 and R11 only being soldered on one side. (Looks like the missing solder was on the ground side, which even took my iron a few seconds to heat up, so I suspect whatever worker made this board didn’t have their iron hot enough.)

Another thing I noticed was the lack of a Zener diode, which I thought was required for a voltage reference? The other thing of note is SMD capacitors C1 (missing), C6, C7 and C8 on the back. There’s plenty of board space on the front, so I thought that was a weird decision. The last oddity is what appears to be a bodge resistor connecting pin 2 of the ATmega to VCC.

The package came with what you’d expect, the unit in a case, three test leads and a ZIF/SMD adapter. In addition to the standards the seller also threw in a power cable for rigging up your own external supply and an extra power connector (not sure what’s up with that).

Here’s full resolution versions of the attached pictures if you want to examine the front or back of the board in detail: http://img.timb.us/index.php?f=TrannyTaster (http://img.timb.us/index.php?f=TrannyTaster)
Title: Re: $20 LCR ESR Transistor checker project
Post by: dentaku on August 30, 2014, 11:59:40 am
So, my MK-168 unit came in today. The build quality is pretty nice overall; it uses an AT328P in a socket, with no footprint for an ICSP header. Looking at the board it seems to have been designed late last year. Some markings on the board: M168_V2.20, M8/168/328_9V_V2.20, 2013.10.16, EZM Electronics Studio.

The one real problem I found was C3 and R11 only being soldered on one side. (Looks like the missing solder was on the ground side, which even took my iron a few seconds to heat up, so I suspect whatever worker made this board didn’t have their iron hot enough.)

Another thing I noticed was the lack of a Zener diode, which I thought was required for a voltage reference? The other thing of note is SMD capacitors C1 (missing), C6, C7 and C8 on the back. There’s plenty of board space on the front, so I thought that was a weird decision. The last oddity is what appears to be a bodge resistor connecting pin 2 of the ATmega to VCC.

The package came with what you’d expect, the unit in a case, three test leads and a ZIF/SMD adapter. In addition to the standards the seller also threw in a power cable for rigging up your own external supply and an extra power connector (not sure what’s up with that).


I have exactly the same one with all the same markings. I just opened it up to make sure it's soldered right and I don't have the bodge resistor on pin 2, C1 is unpopulated and C3 and R11 are soldered just fine and I see no zener.

I'm guessing the jack came with the power cord so they just included it. I've never used it with a battery before so it's nice to be able to plug it in.

I like the ZIF adapter for testing large amounts of capacitors because it's much quicker and less fiddly than mini grabbers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on August 30, 2014, 12:52:36 pm
After doing some reading, it seems C1 being unpopulated is correct. Yeah, I love the ZIF socket. Between that and the SMD pads (I sorted through a drawer of random FETs tonight, so fast) I think using the leads will be rare.

The ZIF doesn't scream quality to me, but it's by no means bad either. (I've seen much worse on much more expensive gear.) I figure I can always buy a new socket if it breaks.


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Title: Re: $20 LCR ESR Transistor checker project
Post by: RLSprouse on August 30, 2014, 05:39:20 pm

Another thing I noticed was the lack of a Zener diode, which I thought was required for a voltage reference? The other thing of note is SMD capacitors C1 (missing), C6, C7 and C8 on the back. There’s plenty of board space on the front, so I thought that was a weird decision. The last oddity is what appears to be a bodge resistor connecting pin 2 of the ATmega to VCC.


I assume the "bodge resistor" you refer to is the little surface mount package.  I believe that is on pin 27, not pin 2, if I remember how to count pins on a DIP.
Title: Re: $20 LCR ESR Transistor checker project
Post by: andrewwong2000 on August 31, 2014, 10:51:52 am
Thought Id share..

I built 3 of Frenchie's Transistor Tester boards to practice my first go at 0603 SMD soldering, plus have a bit of fun.

Great little board that fits neatly behind a LCD display

Thanks to Markus, Karl Heinz and Frenchie !(http://tapatalk.imageshack.com/v2/14/08/31/33be50b04de769e1631c1ccc65bc9362.jpg)


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Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on August 31, 2014, 06:29:33 pm
Why is there an Atmega88 and not a 328 on Frenchies board? And which resistors should be 0.1% ones? Why use 0.1% ones in the first place when the software calibrates itself and there's a voltage reference on board?
Title: Re: $20 LCR ESR Transistor checker project
Post by: radioFlash on August 31, 2014, 08:01:21 pm
R1-R6 on the schematic should be .1%. They are the 680 and 470k resistors.


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Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on August 31, 2014, 08:13:51 pm
But why, if the tester calibrates against a precision voltage reference?
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on August 31, 2014, 08:56:52 pm
No worries! The official Transistor Tester firmware (k and m version) is open source!!! Unfortunately some clone vendors modify the source and claim ownership while violating the copyright of the original authors. It doesn't make much sense to try stopping them, because that would require a lot of money for lawyers. Therefore my advice is to buy only hardware compatible clones, since those can be upgraded to the current firmware version. If you buy a clone with a modified hardware/firmware, you might never get any update from the vendor. And a self-made tester is best one anyway ;)

PS: The next m-firmware version will have a squarewave signal generator (up to 2MHz for 8MHz MCU clock) operated by the rotary encoder supporting dynamic turning velocity.
OK, thanks for response. In order to thank authors I decided to build it myself, even when it will came out not as good as bought one, I feel proud using it  8) (and I did, I use it now very often), without giving money to Chinese for a thing, that they didn't invented   >:( I'll like to try m-version, however, with such stuff I'm dealing with having an inductance meter is very helpful. Seems like I need to think about making another one for m-version exlusively, hmmm...
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on August 31, 2014, 10:01:09 pm

But why, if the tester calibrates against a precision voltage reference?

It doesn't calibrate against a precision reference as I understand it. It simply uses the ADC's reference input which is either VCC or 1.5V.

The 2.5V precision reference is optional. From my understanding of the PDF linked on page 1, it's only used for measuring the battery voltage accurately.

Either way, the more accurate the resistor, the more accurate the calibration.


(Incidentally, the Chinese MK-168 I got uses 0.1% resistors, which shocked the shit out of me. Well, unless they're just painting a purple band on some cheapies!)


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Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on August 31, 2014, 10:04:51 pm


Another thing I noticed was the lack of a Zener diode, which I thought was required for a voltage reference? The other thing of note is SMD capacitors C1 (missing), C6, C7 and C8 on the back. There’s plenty of board space on the front, so I thought that was a weird decision. The last oddity is what appears to be a bodge resistor connecting pin 2 of the ATmega to VCC.


I assume the "bodge resistor" you refer to is the little surface mount package.  I believe that is on pin 27, not pin 2, if I remember how to count pins on a DIP.

Spot on. I was looking at the board with the chip out of the socket when I wrote that.

So this is where the precision reference should go. Lucky I've got about 6 REF5025's in a sealed bag around here somewhere. Time to customize!


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Title: Re: $20 LCR ESR Transistor checker project
Post by: markce on August 31, 2014, 10:19:44 pm
I've got a MK168 as well. It was amazingly accurate in both R end C measuments, but no zener in place.
Looked it up, and it's only used as added function in calibration mode. The voltage regulator used on this
board nice and much better than an ordinary 78l05. Given the construction and the accuracy, I'll not mod it
anywhere soon. Pleased with it as it is.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on September 01, 2014, 01:53:27 am
Yeah, I was just going through the README in Markus’ firmware and it says this:

Quote
The external 2.5V voltage reference should be only enabled if it's at least
10 times more precise than the voltage regulator. Otherwise it would make
the results worse. If you're using a MCP1702 with a typical tolerance of
0.4% as voltage regulator you really don't need a 2.5V voltage reference.

The regulator used in the MK-168 is the AMS1117-5V (http://www.advanced-monolithic.com/pdf/ds1117.pdf), which isn’t quite as good as the MCP1702 and others, but like you said, more than acceptable I think. I might still install the reference for the hell of it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 01, 2014, 05:34:02 pm
It doesn't calibrate against a precision reference as I understand it. It simply uses the ADC's reference input which is either VCC or 1.5V.

The 2.5V precision reference is optional. From my understanding of the PDF linked on page 1, it's only used for measuring the battery voltage accurately.

The optional external 2.5V reference is used to determine the offset of Vcc (5V). That offset has an impact on the self-adjustment of the internal bandgap reference and all measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on September 02, 2014, 08:49:04 am
Right. I was just stating that the optional 2.5V Ref wasn't used as the ADC's reference input or anything.

(And of course by battery accuracy I meant VCC.)


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Title: Re: $20 LCR ESR Transistor checker project
Post by: Scaramanga on September 02, 2014, 10:10:32 am
Hello everyone!

I just bought one of these , version 2.4 2013/07/01

i just wanted to ask:

I saw people in the first pages installing decoupling caps near by the chip, while others don't. What are the benefits of it?
Sorry if i sound silly but i'm not familiar with µC world
Thanks in advance

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 02, 2014, 05:19:53 pm
I saw people in the first pages installing decoupling caps near by the chip, while others don't. What are the benefits of it?
Sorry if i sound silly but i'm not familiar with µC world

The decoupling caps keep the voltage of the power supply stable if the load, i.e. the current draw of the MCU, changes. You can read more about that at https://en.wikipedia.org/wiki/Decoupling_capacitor for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scaramanga on September 03, 2014, 06:29:01 pm
ok thanks for your response  :-+
I'm new at electronics, after thinking about it i don't think i will put more money on this gadget. I'd better spend my time & money into learning more about electronics  rather than trying to modify this low-cost gadget :P
i just removed the zener as suggested & i'll leave it as it is. I'll calibrate it if ever i find a low-tolerance film capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: moemoe on September 03, 2014, 07:00:54 pm
If anyone here should be interested, I'm running a centralized order on my variant of the board. Price per board is 3.50€, shipping (worldwide) 3,10€ or 5,05€ for >2 boards.

It's designed to fit into the http://www.reichelt.de/SP-6000-SW/3/index.html?&ACTION=3&LA=446&ARTICLE=33838&artnr=SP+6000+SW (http://www.reichelt.de/SP-6000-SW/3/index.html?&ACTION=3&LA=446&ARTICLE=33838&artnr=SP+6000+SW) Strapubox 6000, equipped with a http://www.mouser.de/ProductDetail/ELECTRONIC-ASSEMBLY/EA-DOGM162W-A/?qs=sGAEpiMZZMv8dIMJ2cKI/LMZh%252b6hoZs2 (http://www.mouser.de/ProductDetail/ELECTRONIC-ASSEMBLY/EA-DOGM162W-A/?qs=sGAEpiMZZMv8dIMJ2cKI/LMZh%252b6hoZs2) EA DOMG Display (mostly because it's much smaller than a normal 2x16 Display).

All Data is available on https://github.com/maugsburger/avr-component-tester (https://github.com/maugsburger/avr-component-tester) and some images on the first posts here: http://www.mikrocontroller.net/topic/343407 (http://www.mikrocontroller.net/topic/343407) and http://www.mikrocontroller.net/topic/314097 (http://www.mikrocontroller.net/topic/314097)

In opposite to most china versions it can test zener diodes up to 30V, too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 04, 2014, 01:27:23 pm
i just removed the zener as suggested & i'll leave it as it is. I'll calibrate it if ever i find a low-tolerance film capacitor.

It doesn't have to be a low-tolerance film capacitor, any film cap >100nF is fine. I use an 1µF MKT for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on September 04, 2014, 02:27:50 pm
So I built my reference last night! The REF5025 requires a low ESR cap between 1 and 10uF on the output for stability. To keep things nice and compact I dug through my box of donor boards and found a nice 10uF Tantalum SMD on an old motherboard. With a bit of work I was able to solder it to the output lead and ground ring of the SOIC breakout board I was using. I also added a 10uF ceramic across the input and output leads for good measure.

Here it is with a 555 for comparison:
(http://tapatalk.imageshack.com/v2/14/09/04/924a01c916fdf07a9fc0d13d7ee1f890.jpg)

Plus the obligatory close up shot:
(http://tapatalk.imageshack.com/v2/14/09/04/7802d79f2972751ea6fa4ddb1d32a2be.jpg)

I'll mount it to the top of the MK-168 board with some double sided tape and tap GND and VCC directly from two components in front of it, then run a small lead directly to the reference input.

I know this is a bit overkill, but I've got a ton of these REF5025's leftover from a client project awhile back. (These are the high grade versions, too!)


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Title: Re: $20 LCR ESR Transistor checker project
Post by: Scaramanga on September 04, 2014, 05:46:56 pm

It doesn't have to be a low-tolerance film capacitor, any film cap >100nF is fine. I use an 1µF MKT for example.

ah i see

so the quality factor is about the reactance/esr at given frequency

is a mkp capacitor from fluo lamp ok ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on September 05, 2014, 12:35:22 am
Is there an easy way to disable continuous mode with Markus’ firmware? I find it’s a bit wasteful for me, since I’m not testing a string of components at a time. Also, I’ve got to say that this firmware feels a lot slower than the version in the trunk directory. Maybe it’s something in my settings?

Edit: I set #define CYCLE_MAX to 1 in config.h, but it still seems to go more than once sometimes (I know if I hit the button after a measurement it’ll go again, but I don’t touch anything and it’ll go again once and awhile it seems; mainly after I’ve just measured a component).

On another note, I got my reference installed. Works great!

(http://img.timb.us/MK-168_REF5025_1.jpg)

(http://img.timb.us/MK-168_REF5025_2.jpg)

That big capacitor that’s folded over next to the reference board is a 10uF I added to help filter the output of the voltage regulator. Turns out they have *no* capacitor directly on the output! (I’ve got it soldered to the pin of a resistor which is the first thing the regulator’s output connects to [first solder connection coming from the regulator’s tab in the second picture].) This should help keep the regulator’s output a lot more stable.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on September 05, 2014, 01:03:26 am
That big capacitor that’s folded over next to the reference board is a 10uF I added to help filter the output of the voltage regulator. Turns out they have *no* capacitor directly on the output!

If you are using an LDO  or low quiescent current regulator,  they pretty much require caps on the input and output or else they turn into dandy oscillators.  Also the output cap cannot have too high OR LOW of an ESR value.   And there may be limits on the capacitance that they require (again can't be too high or low).  Always check the data sheet when using an LDO or low quiescent current type of regulator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on September 05, 2014, 01:35:00 am
That big capacitor that’s folded over next to the reference board is a 10uF I added to help filter the output of the voltage regulator. Turns out they have *no* capacitor directly on the output!

If you are using an LDO  or low quiescent current regulator,  they pretty much require caps on the input and output or else they turn into dandy oscillators.  Also the output cap cannot have too high OR LOW of an ESR value.   And there may be limits on the capacitance that they require (again can't be too high or low).  Always check the data sheet when using an LDO or low quiescent current type of regulator.

Yup, exactly. That’s why I was surprised there wasn’t one. They were filtering the input from the DC Jack, the input to the LDO and the pins between VCC and GND, but that’s about it. I checked the datasheet for the AMS1117 and it requires one, hence adding the 1uF electrolyte.

TI actually makes some “cap free” LDOs, and a bunch that are stable with ceramic outputs, which can save on the expense of buying tantalums.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on September 05, 2014, 05:06:58 am
Hmmm, my tester seems to be off by an order of a magnitude on capacitors with the 1.14m software. 100uF caps are reading 10uF! Any idea what could be causing this?

It helps if you set the fuse bits for an 8MHz Crystal instead of the internal 1MHz resonator! (http://img.timb.us/emoticon/ughh.gif)

So, my actual and real problem is that I can’t get it to measure inductors at all. :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 06, 2014, 10:18:47 am
is a mkp capacitor from fluo lamp ok ?

Haven't tried one yet, but it should be fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 06, 2014, 10:24:21 am
Is there an easy way to disable continuous mode with Markus’ firmware? I find it’s a bit wasteful for me, since I’m not testing a string of components at a time.

Please press the push button when powering on a little bit longer (>0.3s). For powering off it's the same procedure.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 06, 2014, 10:32:39 am
It helps if you set the fuse bits for an 8MHz Crystal instead of the internal 1MHz resonator!

So, my actual and real problem is that I can’t get it to measure inductors at all. :(

The internal RC oscillator is 8MHz too, but the clock prescaler is set to 8 by default. Are you using an ATmega 168 or 328?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on September 06, 2014, 06:12:13 pm

It helps if you set the fuse bits for an 8MHz Crystal instead of the internal 1MHz resonator!

So, my actual and real problem is that I can’t get it to measure inductors at all. :(

The internal RC oscillator is 8MHz too, but the clock prescaler is set to 8 by default. Are you using an ATmega 168 or 328?

Right, but I had the fuse bits on the Mega328 chip set to the defaults, which is internal @ 1MHz. So I had uploaded the hex and eep with make upload, but forgot to do a make fuses afterwards.

That's why the thing was running so dog slow and not measuring things correctly.

So I did get it to measure a large (500uH) inductor last night. But it's seeing my smaller (4.7uH) ones as capacitors. Is there some sort of limit on the size of inductors it can measure?


Sent from my Smartphone
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 06, 2014, 08:33:34 pm
So I did get it to measure a large (500uH) inductor last night. But it's seeing my smaller (4.7uH) ones as capacitors. Is there some sort of limit on the size of inductors it can measure?

Yes, the lower limit is about 100µH.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on September 06, 2014, 08:37:19 pm

So I did get it to measure a large (500uH) inductor last night. But it's seeing my smaller (4.7uH) ones as capacitors. Is there some sort of limit on the size of inductors it can measure?

Yes, the lower limit is about 100µH.

Thanks! Can you go into more detail on why it's limited to that? I'd be interested in helping to add support for lower and more precise inductor measurements.


Sent from my Smartphone
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on September 06, 2014, 10:37:28 pm
My Chinese version with the graphics display does a fairly decent job on inductors starting out around 20 uH
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on September 07, 2014, 12:20:52 am
Hi:
Could I get anyones thoughts on this meter?
Has anyone purchased this one and been able to update it and how did you do it or is this one not to be purchased. I was looking at the ones with the larger display, but I believe it was mentioned that you cannot update it with the files mentioned here.
http://www.ebay.com/itm/291041497713?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/291041497713?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT)   Thanks for any help.
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: MickM on September 07, 2014, 05:07:44 am
Hi amtpdb;
   I bought one of as a gift.
The AVR is locked by the fusebits.
AVRDUDE will read it ok, but the file is length 0.

Nevertheless it is a good clone, and does ESR

Mick M
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on September 07, 2014, 05:15:12 am
Hi amtpdb;
   I bought one of as a gift.
The AVR is locked by the fusebits.
AVRDUDE will read it ok, but the file is length 0.

Nevertheless it is a good clone, and does ESR

Mick M

Thanks Mick
Is there anything I should know before I buy it to change? Can you put a header on it easy enough to change the program and did you change the program? Did you change the atmega out? Is there one that you would consider other then this one now that you purchased it? I am a newbe, do you need to change out the resistor or anything?
I appreciate your getting back so quickly.
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2014, 10:30:12 am
Thanks! Can you go into more detail on why it's limited to that? I'd be interested in helping to add support for lower and more precise inductor measurements.

Based on the hardware design the only feasable method for measuring inductance is to track the current change of the inductor when a current is applied. To measure low inductances a high test current is required but the MCU's limit is 20mA. In "safe" mode (about 7mA, limited by the 680 Ohms probe resistor) the tester can measure down to about 100µH. But there's also an "unsafe" mode which overloads the MCU's I/O pin for a short period of time and allows a measurement down to 10µH. The unsafe mode is entered if the tester doesn't detect an inductor in the safe mode and the resistance of the DUT is less than 40 Ohms. So far we haven't seen any issues with that, but the measurements in the low inductance range are not very accurate.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on September 07, 2014, 12:21:48 pm
amtpdb;

I bought 2 of these also.  Under the LCD is a DIP socketed 328P.  There is no connector to program it on the board.  You would have to remove it to modify the program.

This is the BEST design because you can buy a second 328P and program it.  Test it on the board  and if it does not work, reinsert the original 328P
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2014, 12:32:44 pm
Some changes for v1.15m to improve the inductance measurement a little bit more. In inductance.c in function MeasureInductance() in the "process counters" section please change:

Code: [Select]
Offset = -4;                /* subtract processing overhead */
to
Code: [Select]
Offset = -3;                /* subtract processing overhead */

Remove or comment out the following line:
Code: [Select]
    Counter += (CPU_FREQ / 2000000);         /* add half of cycles for rounding */

And change
Code: [Select]
  if (Counter <= 500) Flag = 2;         /* signal "inductance too low" */
to
Code: [Select]
  if (Counter <= 100) Flag = 2;         /* signal "inductance too low" */

The changes above will be included in the next release.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on September 07, 2014, 12:52:05 pm

Some changes for v1.15m to improve the inductance measurement a little bit more. In inductance.c in function MeasureInductance() in the "process counters" section please change:

Code: [Select]
Offset = -4;                /* subtract processing overhead */
to
Code: [Select]
Offset = -3;                /* subtract processing overhead */

Remove or comment out the following line:
Code: [Select]
    Counter += (CPU_FREQ / 2000000);         /* add half of cycles for rounding */

And change
Code: [Select]
  if (Counter <= 500) Flag = 2;         /* signal "inductance too low" */
to
Code: [Select]
  if (Counter <= 100) Flag = 2;         /* signal "inductance too low" */

The changes above will be included in the next release.

Thanks, I'll give this a go today and report back!

So, one issue I've run into with reprogramming my Mega328 chips after flashing this firmware is the fact I can't reprogram them! After some head scratching I realized (after some Googling) that it's because the fuse bits are set for an 8MHz crystal and the MCU won't start at all (even for programming) without one in place.

This is about the dumbest fycking thing I've ever seen! Why the hell wouldn't Atmel have designed the chip to default to a "safe mode" using the internal oscillator during programming?

Since I don't have any 8MHz crystals laying around I'm just using male to female jumper straps to go from the xtal ports on the socket to the chip's pins during programming.

(For the record, I'm an MSP430 and ARM programmer mainly, so the concept of setting these type of things via fuses is very alien to me. It seems especially dumb to have clock settings done this way since you can basically lock yourself out of the chip unless you happen to have a HV programmer laying around. I much prefer setting the clock speed via software registers, which has the added advantage of dynamic frequency selections to save power!)


Sent from my Smartphone
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2014, 01:31:37 pm
Since I don't have any 8MHz crystals laying around I'm just using male to female jumper straps to go from the xtal ports on the socket to the chip's pins during programming.

Some ISP programmers provide a clock signal for those cases.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timb on September 07, 2014, 01:34:05 pm
Yeah, I've only got a Bus Pirate and hand-built ArduinoISP Shield (with 16MHz crystal installed). I guess I could generate an 8MHz clock with my function generator? Still a pain the ass though.


Sent from my Smartphone
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on September 13, 2014, 03:41:05 pm
Am I mistaking or is the MCP1700 rated at 6V input, but connected to the 9V battery?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 14, 2014, 12:30:17 pm
Am I mistaking or is the MCP1700 rated at 6V input, but connected to the 9V battery?

The recommended LDO voltage regulator is a MCP1702 which supports an input voltage up to 13.2V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on September 16, 2014, 10:37:06 am
Thank you, I thought so. I have another set of question, if you're a not fed up already:

As I was skimming through the svn repository, I was a bit con-f-used by the following passage in the Makefile:

Quote
# The WITH_UART option enables the software UART  (TTL level output at Pin PC3, 26).
# If the option is deselected, PC3 can be used as external voltage input with a
# 10:1 resistor divider.
#CFLAGS += -DWITH_UART

# With option TQFP_ADC6 or/and TQFP_ADC7 you can use the additional pins of the TQFP or
# the QFN package for external analog input. You should install a 10:1 voltage dividers
# on the selected pin(s).
# If both pins are defined, both voltages are measured with the voltage measure function.
# But for zener diode measurement the ADC6 pin is used, if both pins are defined.
CFLAGS += -DTQFP_ADC6
CFLAGS += -DTQFP_ADC7

# For ATmega8/168/328 processor the option WITH_VEXT can only be set, if the PC3 pin
# is not used for serial output (WITH_UART option).
# For ATmega644/1284 processor the UART has a separate pin.  Therefore the external input
# at pin ADC3 can be enabled separate by setting the WITH_UART option.
CFLAGS += -DWITH_VEXT

So you can measure Zeners or a voltage on ADC6 and additionally another external voltage on ADC7. Do you have to set -DWITH_VEXT for that? I assume not as VEXT says it "can only be set if the PC3 pin is not used." It would be annoying having to abstain from UART to measure voltages.

PC3 gives UART output. If you don't set  -DWITH_UART, you can set -DWITH_VEXT and get an extra voltage input, right? Does that make three  extra voltage inputs, when  -DTQFP_ADC6 and  -DTQFP_ADC7, -DWITH_VEXT are set and -DWITH_UART is not?

Why is there even -DWITH_VEXT and -DWITH_UART? Wouldn't one of them suffice if you can't use VEXT with UART enabled? If you disable UART and VEXT, does PC3 do nothing?

Finally, why is the voltage reference only used for measuring the battery voltage? I'd imagine the whole thing would be more accurate if you calibrated against the optional external voltage reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 17, 2014, 05:42:44 pm
So you can measure Zeners or a voltage on ADC6 and additionally another external voltage on ADC7. Do you have to set -DWITH_VEXT for that? I assume not as VEXT says it "can only be set if the PC3 pin is not used." It would be annoying having to abstain from UART to measure voltages.

Yes, you should set WITH_VEXT if you're using ADC6 and/or ADC7 together with WITH_UART. Just the combination of WITH_VEXT and WITH_UART without TQFP_ADC6 or TQFP_ADC7 set doesn't work. TQFP_ADC6 and TQFP_ADC7 are switches for re-defining the pins used for the external voltage measurement.

Quote
PC3 gives UART output. If you don't set  -DWITH_UART, you can set -DWITH_VEXT and get an extra voltage input, right? Does that make three  extra voltage inputs, when  -DTQFP_ADC6 and  -DTQFP_ADC7, -DWITH_VEXT are set and -DWITH_UART is not?

No, either you got PC3 or ADC6/ADC7.

Quote
Why is there even -DWITH_VEXT and -DWITH_UART? Wouldn't one of them suffice if you can't use VEXT with UART enabled? If you disable UART and VEXT, does PC3 do nothing?

Both are options. If you don't set any of them, both are disabled and PC3 is unused.

Quote
Finally, why is the voltage reference only used for measuring the battery voltage? I'd imagine the whole thing would be more accurate if you calibrated against the optional external voltage reference.

No, the external voltage reference is used to determine the offset of Vcc (5V). That offset is used for all measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 18, 2014, 12:15:47 am
Why is there even -DWITH_VEXT and -DWITH_UART? Wouldn't one of them suffice if you can't use VEXT with UART enabled? If you disable UART and VEXT, does PC3 do nothing?

I'm afraid I might be at least partially responsible for that by virtue of suggesting that when I have no use for serial output, I would rather not waste the microcontroller's resources on generating extra data and noise on the PC3 pin. Prior to this option being available in the make file, I had to go into the source and comment out the #define lines for VEXT because unsetting WITH_UART would result in the device trying to measure voltage every time I accidentally held the test button in a little longer. Very annoying when you have no zener extension.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlessandroAU on September 21, 2014, 07:34:21 pm
Hey Alessandro

That's the "LCR T3" design.

Any chance you can read the flash and EEPROM and email to me ?

These ones use an older version of the firmware but I'm trying to figure out that display so it can be upgradeable.

That one you have has a 6pin ISP pin pad but it's reversed on the component side :)



Sent from my iPhone using Tapatalk

I tired to read the chip using my tl866. I can get the chip ID fine, but when I try to read from it just appears blank. Some form of copy protection?
Title: Re: $20 LCR ESR Transistor checker project
Post by: pol098 on September 22, 2014, 08:53:54 pm
In case anyone is interested in the graphics versions: they are described and sold within China on a Web site in Chinese only:
http://fish8840.taobao.com/ (http://fish8840.taobao.com/) I prefer to open it in Google Chrome, which offers to translate it automatically, or on a right-click. I don't know whether the many sources of these devices buy from fish8840 (in which case they'd be all be of equal quality) or make their own copies.

Presumably fish8840 is the originator of the Chinese hardware versions (although they themselves may be imitated!), and weiweitm adapted the software. The reason for production of a graphics version given is that a text-only display in Latin characters is difficult for Chinese people, which makes sense; there are traditional and simplified Chinese, and English-language versions. There are two versions, an older one with a green display, and a later one with a slightly larger blue display; both are sold, with the blue one a little more expensive. The pictures don't show a crystal visible on the board; it could be there but hidden. As far as I can tell the later board was released in March 2014; the only software appears to be weiweitm's version 2.1 (with no mention of providing source code). I don't know if there is any provision at all for software updates (socketed chip, header, any intention to produce downloadable updates). There is a picture of an elegantly cased version, branded Yiwanjia, but no indication (such as price) that it exists.

Foreigner Markus F is acknowledged. The translation is difficult to understand in detail; I think Translate's "shelves without shell" are uncased boards!

Web pages of the two hardware versions (Chinese):
Larger screen, blue, backlit 25/3/2014, software shows as 2.1 on pictures:
http://item.taobao.com/item.htm?spm=a1z10.5.w4002-2323427594.16.IhvBUf&id=36323329572 (http://item.taobao.com/item.htm?spm=a1z10.5.w4002-2323427594.16.IhvBUf&id=36323329572)
Smaller green graphics screen version:
http://item.taobao.com/item.htm?spm=a1z10.5.w4002-2323427594.19.IhvBUf&id=37659767669 (http://item.taobao.com/item.htm?spm=a1z10.5.w4002-2323427594.19.IhvBUf&id=37659767669)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 23, 2014, 11:51:50 am
Foreigner Markus F is acknowledged. The translation is difficult to understand in detail; I think Translate's "shelves without

Evidently the firmware is based on Karl-Heinz' source code. So much for proper credits. >:(
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 24, 2014, 08:15:35 am
I suspect that they are simply ignorant of the fact that someone other than "Foreigner Markus F." needs to be credited. Maybe if you or K.-H. contacted them and told them what needs to be done, this could be easily corrected. Just a thought.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on September 24, 2014, 03:27:52 pm
I bought one of the blue testers http://www.ebay.co.uk/itm/New-Transistor-NPN-PNP-MOSFET-Diode-Tester-Capacitor-ESR-Resistor-Meters-UK-Ship-/271551234681 (http://www.ebay.co.uk/itm/New-Transistor-NPN-PNP-MOSFET-Diode-Tester-Capacitor-ESR-Resistor-Meters-UK-Ship-/271551234681) the other day and its a great piece of kit for the price but I had to carry out some modifications to get it to behave.

1.
It would sometimes display "VCC=x.xV" underneath the battery voltage and according to ttester_eng110k.pdf this should only happen if there is a voltage reference installed, which this one does not have. The voltage it would show changed every measurement along with the test result, a 2.2k pull-up resistor from VCC to pin 27 fixed this.

Quote
Missing precision voltage reference Usually the software should detect the missing voltage reference with the unconnected pin PC4. In this case no VCC=x.xV message should appear in row 2 of the LCD on power on. If this message appear without the reference, you should connect a 2:2k resistor to the PC4 input and VCC.
It was almost like it was switching between the internal reference and what ever pin 27 was floating at, for example the battery voltage would randomly go from reading 8.5v to 7v and then 9v. The test results were only accurate when the uC detected no reference was installed.

2.
The AMS1117-5.0 voltage regulator was missing bypass capacitors on its output so I paralleled up a 100nF and 22uF as per the datasheets recommendation. Looking on my oscilloscope I noticed a slightly cleaner output and a much better transient response. Not sure if this makes any difference to measurements though.

3.
C1 was missing on the AREF pin so I installed a 1nF as per the manuals suggestion (I have firmware version 1.11k).

4.
On mine the wire to the green front cover connector had a dry solder joint so I redid it, on closer inspection each connector has a small hole on the end for the wires to thread through but for some reason they were ignored during manufacturing.

5
The track routing for AGND at pin 22 took a separate and very scenic route around the PCB before it met up with pin 7 and the uC's decoupling capacitor, effectively isolating it from said capacitor. So I soldered a 100nF ceramic directly across pins 20 and 22 in an attempt to reduce the effects of the long trace on the analog sections supply rails.

This image shows the additional capacitor and the long route from AGND to the regulator and factory decoupling cap on pin 8 GND.

(https://i.imgur.com/Jg24EXq.jpg)

Too anyone who has one of these, have you noticed that the ESR measurements tend to change depending on which way around you have the probes? Seems to be related to the temperature of the capacitor and my fingers heating it slightly, the warmer the cap the lower the ESR reading.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pol098 on September 24, 2014, 06:39:06 pm
... Maybe if you or K.-H. contacted them and told them what needs to be done, this could be easily corrected ...

It might even be interesting for somebody (I think it would have to be someone who knows Chinese) to contact the people making the Chinese graphics devices and software, welcome their activity, and suggest that they could add their contributions to the shared software, that they would get useful feedback from here (e.g. Alex1's recent detailed contribution should be helpful to them), and that a system could be set up to distribute updates? They could even sell pre-programmed ATmega328s to those who don't want to do it themselves.

I hope this doesn't step on the toes of the legitimate developers here, not my intention, just a "more the merrier" idea.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on September 24, 2014, 06:46:43 pm
I just purchased the one listed below. Does anyone have any suggestions on what should be done to make it more accurate or better? By this I see that some of you replaced resistors and caps, reprogrammed the chip (where is the latest update?).
Thanks for any help. I have been following this thread for some time but still  don't know too much about electronics but want to learn! That is one reason I purchase this item.
Thanks

http://www.ebay.com/itm/291041497713?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/291041497713?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 25, 2014, 05:29:06 pm
It might even be interesting for somebody (I think it would have to be someone who knows Chinese) to contact the people making the Chinese graphics devices and software, welcome their activity, and suggest that they could add their contributions to the shared software, that they would get useful feedback from here (e.g. Alex1's recent detailed contribution should be helpful to them), and that a system could be set up to distribute updates? They could even sell pre-programmed ATmega328s to those who don't want to do it themselves.

That's a good idea! I always encourage contributors and users to send bug reports, add-ons, modifications and so on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on September 25, 2014, 11:44:11 pm
@madires Looking on a scope during a capacitance test it seems that this tester will apply a high reverse voltage directly across the capacitor during one half of the cycle, which for an electrolytic is bad.

Should it be placing such a reverse voltage across the capacitor?

Below shows my scope which is DC coupled to the output of the tester with a 1200uF capacitor connected across it. Shouldn't this cause the capacitor to break down during one half of the test cycle?

(https://i.imgur.com/utMEORC.png)

2v/div 500ms/div
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on September 26, 2014, 01:06:30 am
It's not long enough or high enough of a voltage/current to do any damage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on September 26, 2014, 01:13:25 am
It's not long enough or high enough of a voltage/current to do any damage.

But wouldn't it be safer to limit the test voltage to something under a capacitors reverse breakdown voltage of 1.5v?
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on September 26, 2014, 01:19:57 am
It's not long enough or high enough of a voltage/current to do any damage.

But wouldn't it be safer to limit the test voltage to something under a capacitors reverse breakdown voltage of 1.5v?

You can't do that with a processor/circuit that is using 5V digital I/O pins.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on September 26, 2014, 02:21:17 am
You can't do that with a processor/circuit that is using 5V digital I/O pins.

What about if one lead of the tester was designated as positive so that it could always be connected to the positive side of the capacitor by the user, or would the way the test works break that?
Title: Re: $20 LCR ESR Transistor checker project
Post by: SeanB on September 26, 2014, 04:40:20 am
LONG term reverse voltage will damage an electrolytic, but a short term ( less than 1 second) non repetitive pulse will have no effect. Repetitive reverse pulses will destroy it, asa they average out as a long term reverse voltage. Remember a non polarised electrolytic is subjected to a reverse voltage on each foil, and they last decades in service.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on September 26, 2014, 07:18:38 am
Fair enough then if its just long term reverse polarity that does damage.

I was just having a :scared: moment thinking that I might have just done something stupid on an appliance I am repairing for a friend.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 26, 2014, 11:14:33 am
@madires Looking on a scope during a capacitance test it seems that this tester will apply a high reverse voltage directly across the capacitor during one half of the cycle, which for an electrolytic is bad.

Should it be placing such a reverse voltage across the capacitor?

Below shows my scope which is DC coupled to the output of the tester with a 1200uF capacitor connected across it. Shouldn't this cause the capacitor to break down during one half of the test cycle?

What you saw seems to be some test for another component. During the capacitance measurement the polarity of an electrolytic cap might be reversed, but the current is limited to 7mA and 10ms pulses for the first phase (high capacitance) and is limited to 10µA for the second phase (low capacitance). During the first phase a voltage of more than 300mV across the cap will end the test. The test for small capacitance limits the voltage to the internal bandgap reference (ATmega168/328: 1.1V). The ESR measurement creates pulsed forward and reverse voltages for a few µs each, also limited to 7mA. If you're concerned about running the other tests you could run the tester's in-circuit ESR measurement via the menu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on September 27, 2014, 10:48:04 am
What you saw seems to be some test for another component.

During the first phase a voltage of more than 300mV across the cap will end the test.

So it shouldn't be doing the test displayed on the waveform? The atmega328 has version 1.11k according to the end of the self calibration routine.

If you're concerned about running the other tests you could run the tester's in-circuit ESR measurement via the menu.

What is the procedure to access this menu?

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on September 27, 2014, 12:26:06 pm
The atmega328 has version 1.11k according to the end of the self calibration routine.
Latest version should be 1.10k.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on September 27, 2014, 12:39:05 pm
The atmega328 has version 1.11k according to the end of the self calibration routine.
Latest version should be 1.10k.

It definitely says 1.11k.

What you saw seems to be some test for another component. During the capacitance measurement the polarity of an electrolytic cap might be reversed, but the current is limited to 7mA and 10ms pulses.

During the first phase a voltage of more than 300mV across the cap will end the test. The test for small capacitance limits the voltage to the internal bandgap reference (ATmega168/328: 1.1V).
[/b]

This definitely doesn't look right then.

Some waveforms taken during a capacitor test, all 2 volts and 1 second a division.
From top to bottom is 10uF, 1500uF (reads 1222uF) and then 2200uF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 27, 2014, 02:00:16 pm
So it shouldn't be doing the test displayed on the waveform? The atmega328 has version 1.11k according to the end of the self calibration routine.

The tester runs several checks to detect the component type and the capacitor check is done at the end. What you saw isn't probably part of the capacitance measurement but some other test done before the capacitance check.

Quote
What is the procedure to access this menu?

For the k-firmware it's a long key press (>500ms).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on September 27, 2014, 02:24:29 pm
The tester runs several checks to detect the component type and the capacitor check is done at the end. What you saw isn't probably part of the capacitance measurement but some other test done before the capacitance check.

Would your "m" firmware 1.15m act any differently?

Quote
For the k-firmware it's a long key press (>500ms).

I can't seem to access it at all and holding down the button for too long gives a timeout error. Maybe the Chinese have started to disable that menu by modifying the code before flashing the uC.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 27, 2014, 04:06:08 pm
Would your "m" firmware 1.15m act any differently?

A little bit different, but mostly the same.

Quote
I can't seem to access it at all and holding down the button for too long gives a timeout error. Maybe the Chinese have started to disable that menu by modifying the code before flashing the uC.

The menu was added in 1.10k and is enabled with the WITH_MENU option in the Makefile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 27, 2014, 11:45:21 pm
I can't seem to access it at all and holding down the button for too long gives a timeout error. Maybe the Chinese have started to disable that menu by modifying the code before flashing the uC.

Sometimes it's just a matter of timing.

"Timeout!" should probably say "Shutting down..." or something similar instead, by the way. It describes the event perfectly, but not the action that's being taken.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on September 28, 2014, 01:57:31 am
Yeah its definitely not been enabled on this unit.

I've spent a good 30 minutes finger blasting the test button for different intervals but nothing comes up.

I am wondering since I don't have the correct hardware to program the atmega328, would it be possible to use an arduino uno to do the job of programmer instead?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 28, 2014, 04:48:54 am
I don't have an Arduino, but I'd be surprised if you couldn't. Have a look at this: Programming AVR with Arduino (https://www.youtube.com/watch?v=_ZL-YNOH_jA#ws).
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on September 28, 2014, 07:53:31 am
Yes, every Arduino can be used as an in-system programmer (ISP) for Atmegas. The board of your tester must have a programming header, though. If it doesn't, you need to botch wire directly onto the pins your tester's microcontroller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on September 29, 2014, 01:39:54 am
Hi:
I purchased this meter:http://www.ebay.com/itm/291041497713?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
and purchased a  ATmega328P-PU with Arduino UNO bootloader.
I went through the postings here and found postings as to what to burn on the chip. Not quite up on this as a few mentioned opened several file and options and I have no idea which one to pick and if there is anything else to do? Also there has been mention of the fuses to set. On my pick programmer I knew where to set these.  I downloaded WinAVR and don't quite know where  to set them if I could find them!
Any help would be appreciated.
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: Richard Crowley on September 29, 2014, 02:48:40 am
You have not explained WHAT you are attempting to do?
The kit comes with a pre-programmed microcontroller, so WHY do think you want to re-blast the firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on September 29, 2014, 02:58:00 am
I want to make sure it is updated.
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on September 29, 2014, 06:24:55 am
Connect all three testpoints toghether with a wires, then press the button on your tester. This will start a selftest. Follow the instructions on the LCD (at some point you might have to disconnect the wires again and/or put a capacitor on the test points). At the end of the selftest your unit will display its firmware version, e.g. "1.10k". Then you'll see if it is up to date.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on September 29, 2014, 06:58:28 am
Hi:
It's 1.11

I have an atmel328p and trying to use WinAVR with a Sparkfun  Pocket avr programmer. I am new to this and need or would like some help if you can.
Thanks
Don

I pulled out the Make file and loaded it into WinAVR and I think that is the one to use?
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on September 29, 2014, 07:48:21 am
There's two versions of the software. Latest Markus version would be 1.15m (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/). Karl-Heiz's firmware has the version 1.11k.

I never used winavr, but with Avrdude and GNUmake installed you can do it all from command line. First you need to know your hardware. The most important stuff being:

You have an atmega328p so -> PARTNO=m328p
What type of LCD do you use?
Is there a crystal on your board?
Do you have a bunch of transistors in your battery power circuit?
Is there a voltage divider measuring the battery voltage?
The pocket avr programmer is based on the usbtiny so -> PROGRAMMER=usbtiny and PORT=usb

According to that, you'll need to set the Makefile options. Did you read the Makefile (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/) and the documentation (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/?view=tar)? You'll also need to be more specific about your problems. We can't really guide you through what to do, if you just say 'I don't know winavr'. Try it, and then tell us, what did and didn't work. Be very careful with the fuse bits or you risk bricking your controller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 29, 2014, 09:47:51 am
Then most likely you have Markus' firmware. Latest version would be 1.15m (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/). Karl-Heiz's firmware has the version 1.10k.

Just a small hint ;) Karl-Heinz' trunk version (current version under development) is 1.11k.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amtpdb on September 29, 2014, 06:23:56 pm
Thanks for getting back.
I'll give it a try and see what happens.
Thanks again.
Don
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on October 03, 2014, 10:06:31 am
I don't have an Arduino, but I'd be surprised if you couldn't. Have a look at this: Programming AVR with Arduino (https://www.youtube.com/watch?v=_ZL-YNOH_jA#ws).
Thanks I will have a look into it.

That's a good idea! I always encourage contributors and users to send bug reports, add-ons, modifications and so on.

How about having a buzzer that gives a small chime when the component is done being tested like on the peak atlas series. I'm guessing all it would need is for one of the chips outputs to pulse high once or twice for a couple hundred milliseconds.

http://youtu.be/8EXcN9kUwUc?t=15m28s (http://youtu.be/8EXcN9kUwUc?t=15m28s) its from 15:28 if the youtube autotime function doesn't work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2014, 11:27:22 am
How about having a buzzer that gives a small chime when the component is done being tested like on the peak atlas series. I'm guessing all it would need is for one of the chips outputs to pulse high once or twice for a couple hundred milliseconds.

Could be useful for large electrolytic caps when the tester needs some time for the measurement. For all other components the tests are quite fast. If you like to have a buzzer please design an add-on and write the code driving the buzzer. That would be a good way to start with MCUs ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hutale on October 07, 2014, 08:06:09 pm
There is an LCR 2.9 bridge, meter kit with video found at http://youtu.be/ZQ33AR1ffFI (http://youtu.be/ZQ33AR1ffFI) and doc at http://lcr.is-best.net/en/ (http://lcr.is-best.net/en/) . This is a LCR/RLC/in-circuit C/ESR meter measuring L/C/R/Z/Rs/ESR/X/Q/D/Phase angle with 100Hz/1kHz/10kHz sine test signals, base on auto-balancing bridge technique. Maybe you are interested in it too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Richard Crowley on October 07, 2014, 08:38:29 pm
All three of those gadgets on Dr. Le Hung's website look interesting to me.
But he doesn't appear to be actively selling them.  Or at least there is no indication on his web pages.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on October 08, 2014, 10:06:22 am
All three of those gadgets on Dr. Le Hung's website look interesting to me.
But he doesn't appear to be actively selling them.  Or at least there is no indication on his web pages.

He does have a "get one" page but it looks like you need to email him about purchasing one.

http://lcr.is-best.net/en/build.htm (http://lcr.is-best.net/en/build.htm)
Title: Re: $20 LCR ESR Transistor checker project
Post by: diogoc on October 09, 2014, 01:47:31 pm
It is possible to use the open source code in this chinese copy with graphic display?
http://www.aliexpress.com/item/Small-LCD-Transistor-Tester-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/1882283481.html (http://www.aliexpress.com/item/Small-LCD-Transistor-Tester-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/1882283481.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on October 09, 2014, 07:56:10 pm
It is possible to use the open source code in this chinese copy with graphic display?
http://www.aliexpress.com/item/Small-LCD-Transistor-Tester-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/1882283481.html (http://www.aliexpress.com/item/Small-LCD-Transistor-Tester-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/1882283481.html)

Not without a lot of work and possible board modifications.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 09, 2014, 11:56:54 pm
...possible board modifications.

What do you have in mind?
Title: Re: $20 LCR ESR Transistor checker project
Post by: diogoc on October 10, 2014, 07:43:04 am
The schematic should be similar, so only need a firmware with fonts and graphics compatible with that lcd
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 10, 2014, 12:18:42 pm
It is possible to use the open source code in this chinese copy with graphic display?
http://www.aliexpress.com/item/Small-LCD-Transistor-Tester-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/1882283481.html (http://www.aliexpress.com/item/Small-LCD-Transistor-Tester-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/1882283481.html)

The k-firmware supports ST7565 compatible displays, but I don't know which controller the display of that clone got.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 11, 2014, 12:59:13 am
That LCD looks small... could it be a Nokia? There was an early attempt (https://translate.google.com/translate?sl=ru&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fvrtp.ru%2Findex.php%3Fshowtopic%3D16451%26st%3D330&edit-text=&act=url) to use such a display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: andrija on October 13, 2014, 06:28:00 am
I bought the graphical LCD version from EBay (fish...) that I stumbled upon while doing some other shopping and before I knew what it was and where it originated from. Now that I've read good part of this thread, I don't think I want to mess around with mine. I wouldn't mind buying another one, though, with the intention of being able to update its firmware. Looking at the documentation of the original project, there is a version for ATMega644 or 1284; there are schematics in that pdf and everything. Has crystal measurements (I think), DC-DC for Zener (again, I think), input protection with rail-to-rail zeners and tons of more parts than the one I've got, which doesn't have much more than a few R, a few C and uC and screen. But no one seems to be talking about it (ATMega644)? Does this actually exist (there seems to be code for it)? Can I buy it? Or do I need to design a PCB for it myself (if the software already exist, that's a viable option for me).
Title: Re: $20 LCR ESR Transistor checker project
Post by: diogoc on October 13, 2014, 08:53:41 am
That LCD looks small... could it be a Nokia? There was an early attempt (https://translate.google.com/translate?sl=ru&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fvrtp.ru%2Findex.php%3Fshowtopic%3D16451%26st%3D330&edit-text=&act=url) to use such a display.

Is not a nokia lcd because this have a resolution of 128x64.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 13, 2014, 07:00:28 pm
Looking at the documentation of the original project, there is a version for ATMega644 or 1284; there are schematics in that pdf and everything. Has crystal measurements (I think), DC-DC for Zener (again, I think), input protection with rail-to-rail zeners and tons of more parts than the one I've got, which doesn't have much more than a few R, a few C and uC and screen. But no one seems to be talking about it (ATMega644)? Does this actually exist (there seems to be code for it)? Can I buy it? Or do I need to design a PCB for it myself (if the software already exist, that's a viable option for me).

I haven't seen any clone with an ATmega644 yet, so you're welcome to make a PCB yourself ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: a1976888 on October 14, 2014, 05:12:36 pm
Hi,
I was looking for a cheap ESR meter to make in circuit capacitor tests.
Could someone who bought any of these tell me if this function is usable in real word repairing tasks, please ?
Which model did you buy ?
Thanks!

PS : Wonderful project !  :clap:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on October 14, 2014, 09:37:15 pm
I was looking for a cheap ESR meter to make in circuit capacitor tests.
Could someone who bought any of these tell me if this function is usable in real word repairing tasks, please ? Which model did you buy ? Thanks!

The ESR measurement can be used to tell you if the capacitor is failing even if the capacitance measures within spec. As for in-circuit testing your mileage may vary, it's highly dependent on the circuit your testing. This will not discharge your capacitor prior to testing. Nor do they offer input protection (at least last time I looked).

These $20 meters measure resistance and semiconductors as well as capacitance and ESR. They aren't really a replacement for the handheld meters (DER EE DE-5000 - great value) or more expensive proper bench top LCR meters which may offer larger measurement ranges and more accuracy. More expensive meters may be able to take 4 wire measurements for better accuracy.

In addition to capacitance value and ESR (equivalent series resistance) there is also Q (quality factor) which is its efficiency at frequency or inverse of D (dissipation factor). There is also IR (insulation resistance) which is the capacitors ability to withstand current leakage.  Using deduction combined with a multimeter and capacitance/ESR meter should get you through 95% of situations.

There is no best Chinese ESR meter as there is negative aspects in all of them. such as no programming header, no crystal, no external power, less accurate, bad connector design, shortcuts. So take your pick it's only $20.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on October 14, 2014, 09:55:11 pm
PS : Wonderful project !  :clap:

FYI the project is actually on this German website:
http://www.mikrocontroller.net/articles/AVR_Transistortester (http://www.mikrocontroller.net/articles/AVR_Transistortester)

When you buy a Chinese $20 clone in most cases your really buying the project where it was at a few years ago. You can modify and upgrade them if you have the skill, but the reason why they are so popular is they are dirt cheap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: i4004 on October 15, 2014, 01:52:53 am
All three of those gadgets on Dr. Le Hung's website look interesting to me.
But he doesn't appear to be actively selling them.  Or at least there is no indication on his web pages.

He does have a "get one" page but it looks like you need to email him about purchasing one.

http://lcr.is-best.net/en/build.htm (http://lcr.is-best.net/en/build.htm)

yeap, about 55eur in europe for meters (55eur each)..dunno about reflow controller....that would be about 70$ but dunno how much more for shipping to usa or elsewhere...ask him...he's a good guy.

the soldering on the meter pics i got looks very nice...
Title: Re: $20 LCR ESR Transistor checker project
Post by: a1976888 on October 15, 2014, 12:38:43 pm
I was looking for a cheap ESR meter to make in circuit capacitor tests.
Could someone who bought any of these tell me if this function is usable in real word repairing tasks, please ? Which model did you buy ? Thanks!

The ESR measurement can be used to tell you if the capacitor is failing even if the capacitance measures within spec. As for in-circuit testing your mileage may vary, it's highly dependent on the circuit your testing. This will not discharge your capacitor prior to testing. Nor do they offer input protection (at least last time I looked).

These $20 meters measure resistance and semiconductors as well as capacitance and ESR. They aren't really a replacement for the handheld meters (DER EE DE-5000 - great value) or more expensive proper bench top LCR meters which may offer larger measurement ranges and more accuracy. More expensive meters may be able to take 4 wire measurements for better accuracy.

In addition to capacitance value and ESR (equivalent series resistance) there is also Q (quality factor) which is its efficiency at frequency or inverse of D (dissipation factor). There is also IR (insulation resistance) which is the capacitors ability to withstand current leakage.  Using deduction combined with a multimeter and capacitance/ESR meter should get you through 95% of situations.

There is no best Chinese ESR meter as there is negative aspects in all of them. such as no programming header, no crystal, no external power, less accurate, bad connector design, shortcuts. So take your pick it's only $20.

Thanks for your clear answer.
I think that limitations you pointed out are ok for 20$.
I already have a DMM with capacitance measurement capabilites but I thinks that deduction plus capacitance measure are not enough to surely identify bad caps. It's the reason why I think I need at least en ESR meter to do that. And in circuit testing would be a really nice feature...

As per Chinese ESR meter I'd like to buy a model that could be upgraded with project improvements. No external power, accuracy and shortcuts would be no problem as I could fix them by myself. But crystal and programming header would be nice (or at least a socket 328)...

This one look nice (crystal, socket, large display, upgradable?) :
http://www.aliexpress.com/item/12864-LCD-GM328-transistor-tester-ESR-meter-Cymometer-square-wave-generator-Free-shipping/2052241237.html (http://www.aliexpress.com/item/12864-LCD-GM328-transistor-tester-ESR-meter-Cymometer-square-wave-generator-Free-shipping/2052241237.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: a1976888 on October 15, 2014, 12:40:46 pm
PS : Wonderful project !  :clap:

FYI the project is actually on this German website:
http://www.mikrocontroller.net/articles/AVR_Transistortester (http://www.mikrocontroller.net/articles/AVR_Transistortester)

When you buy a Chinese $20 clone in most cases your really buying the project where it was at a few years ago. You can modify and upgrade them if you have the skill, but the reason why they are so popular is they are dirt cheap.

Are you talking about lacks of hardware or software ?

Thanks for the project link !
Title: Re: $20 LCR ESR Transistor checker project
Post by: andrija on October 29, 2014, 04:12:09 am
I am looking at the extended version schematics with ATmega644 and there are a few things I don't get. First, why do they say the DC-DC converter should be on a separate board? I am not even sure how would that work as they don't specify what exactly should be on that other board, I guess the whole section with the "button" and battery being the only inputs and TP5 (external test) being output; but why? Second, what do they mean by "button" annotation? Just a name for that connection point or is there supposed to be something else there?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 29, 2014, 05:00:34 pm
I am looking at the extended version schematics with ATmega644 and there are a few things I don't get. First, why do they say the DC-DC converter should be on a separate board? I am not even sure how would that work as they don't specify what exactly should be on that other board, I guess the whole section with the "button" and battery being the only inputs and TP5 (external test) being output; but why?

The idea is to keep the switching noise away from the test pins. It doesn't need to be another PCB, just have it separated from the main circuit. I've got two boards with DC-DC converters on the same PCB and got no issues so far (one board with a DC-DC converter module and the second one with a classic boost converter). Also I really recommend to have a dedicated LDO for the DC-DC converter. Otherwise it would cause some trouble to the 5V of the main circuit (voltage drop when button is pressed and triggering the MCU's brown-out-detection).

Quote
Second, what do they mean by "button" annotation? Just a name for that connection point or is there supposed to be something else there?

Seems to be just an annotation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: andrija on November 01, 2014, 12:52:14 am
Thanks, I concur with what you are saying. Regarding separate regulator for the DC-DC, the extended schematics does have its own MCP1702-5 so it should be ok.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on November 18, 2014, 03:41:57 pm
I have noticed something interesting about the tester. I have mine set to show me several measurements in a row. When I just turn it on normally, the measurement results stay on for a short while, and then another measurement is performed. If I go to the menu and choose Transistor to go back to normal operation, the result stays on the screen longer! Or at least it feels like it stays longer. How much longer, I don't know, seems somewhat random. I actually like this bug. I think there should be an easy way to be able to tell the tester to have the result on the screen for a longer or shorter time (a menu option, along with turning on and off nano for caps?).

Has anyone else noticed this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2014, 05:59:06 pm
I have noticed something interesting about the tester. I have mine set to show me several measurements in a row. When I just turn in on normally, the measurement results stay on for a short while, and then another measurement is performed. If I go to the menu and choose Transistor to go back to normal operation, the result stays on the screen longer! Or at least it feels like it stays longer. How much longer, I don't know, seems somewhat random. I actually like this bug. I think there should be an easy way to be able to tell the tester to have the result on the screen for a longer or shorter time (a menu option, along with turning on and off nano for caps?).

Please try to press the test button a little bit longer when powering on the tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on November 18, 2014, 06:18:27 pm
What for?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2014, 06:52:43 pm
What for?

For a longer display period.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on November 18, 2014, 07:02:21 pm
I didn't know about that, thanks. Undocumented feature? Doesn't seem to make a difference in my case though. Hard to do, too, because if I hold it a fraction of a second too long it just goes into the menu. Using 1.11k r355 by the way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2014, 07:44:13 pm
I didn't know about that, thanks. Undocumented feature? Doesn't seem to make a difference in my case though. Hard to do, too, because if I hold it a fraction of a second too long it just goes into the menu. Using 1.11k r355 by the way.

IIRC it's 300ms for the extended display period and 600ms for the menu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on November 18, 2014, 08:20:30 pm
Thank you, that really helps. I finally managed to get the timing right. :-/O Looks like half the time I tend to press the button longer when I exit the menu than I do when turning on the device. It sure feels like a bug though if you don't know that it's a feature.

Oh, and there's really no need to "QFT" each of my posts. I rarely make such significant changes to them that would warrant it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: icpart on November 22, 2014, 06:27:54 am


As per Chinese ESR meter I'd like to buy a model that could be upgraded with project improvements. No external power, accuracy and shortcuts would be no problem as I could fix them by myself. But crystal and programming header would be nice (or at least a socket 328)...

This one look nice (crystal, socket, large display, upgradable?) :
http://www.aliexpress.com/item/12864-LCD-GM328-transistor-tester-ESR-meter-Cymometer-square-wave-generator-Free-shipping/2052241237.html (http://www.aliexpress.com/item/12864-LCD-GM328-transistor-tester-ESR-meter-Cymometer-square-wave-generator-Free-shipping/2052241237.html)
I bought this tester and when it arrives I can do  short review here in the forum. Also I want to make some test with it for software upgrade and 16x2 LCD Panel.
Title: Re: $20 LCR ESR Transistor checker project
Post by: janengelbrecht on November 22, 2014, 06:35:59 am
I Have this one http://www.aliexpress.com/item/frss-shipping-5pcs-latest-Version-Mega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter/1778135807.html (http://www.aliexpress.com/item/frss-shipping-5pcs-latest-Version-Mega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter/1778135807.html) same software execpt for display part. Would appriciate information on how to to upgrade firmware :) I Have the old software for a 2 line alphanumeric display. But my hardware is with a graphical LCD display (newer version!): here it is - feel free to collect it : https://app.box.com/s/rj03grtur3xonxi7mzud (https://app.box.com/s/rj03grtur3xonxi7mzud)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 22, 2014, 04:49:33 pm
I Have this one http://www.aliexpress.com/item/frss-shipping-5pcs-latest-Version-Mega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter/1778135807.html (http://www.aliexpress.com/item/frss-shipping-5pcs-latest-Version-Mega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter/1778135807.html) same software execpt for display part. Would appriciate information on how to to upgrade firmware :) I Have the old software for a 2 line alphanumeric display. But my hardware is with a graphical LCD display (newer version!): here it is - feel free to collect it : https://app.box.com/s/rj03grtur3xonxi7mzud (https://app.box.com/s/rj03grtur3xonxi7mzud)

If the display is ST7565 compatible you can use the k-firmware. Otherwise you got bad luck and have to stick with the cloner's firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: briselec on December 03, 2014, 08:32:48 pm
nothing obvious at mikrocontroller.net site. i dont speak german and like many diy hobbyists not good with code suppositories. 

I want to know where I can get code suppositories.
That would make me a genuine smart arse   :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on December 03, 2014, 08:45:01 pm
Grave diggin' are we? April 1st.
Title: Re: $20 LCR ESR Transistor checker project
Post by: magnetus on December 12, 2014, 09:55:00 pm
can anyone help me please?

i got a Chinese transistor tester and tried to update it using the k-firmware now no screen wont display anything. i got the transistor tester 2014-07 by fish8840

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: andrija on December 12, 2014, 10:19:40 pm
can anyone help me please?

i got a Chinese transistor tester and tried to update it using the k-firmware now no screen wont display anything. i got the transistor tester 2014-07 by fish8840

thanks

As explained earlier in the thread, many Chinese testers - and the one you mentioned in particular, which I also have myself - use different hardware with which they supply their own, customer, modified firmware. You CAN'T use the vanilla "official" firmware with that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: magnetus on December 13, 2014, 12:47:36 am

[/quote]

As explained earlier in the thread, many Chinese testers - and the one you mentioned in particular, which I also have myself - use different hardware with which they supply their own, customer, modified firmware. You CAN'T use the vanilla "official" firmware with that.
[/quote]

thanks for the input. I installed a HD4480 LCD and it works ok now.
now this display is 16x2
can i use a 20x4?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 13, 2014, 11:14:27 am
thanks for the input. I installed a HD4480 LCD and it works ok now.
now this display is 16x2
can i use a 20x4?

Yes, but the extra screen estate is used for displaying debugging information mostly (if enabled). AFAIR, supporting 20x4 text displays for the UI is on the to-do list. If you like to have a graphical display, get a ST7565 compatible one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 22, 2014, 12:32:48 am
Sorry to be asking about a rather old posting in this lengthy thread. I have a board that is almost identical to the one shown in the picture from the posting below. The only difference I can see is the binding posts that mine doesn't have.

I replaced the zener with the 2.5V reference and everything works OK. When I replaced the 78L05 with the recommended LDO regulator, the board still works, but now reports that the 9V battery is low, at 7V. Yes, I did take into account the different pinout between parts.

Other than the added bypass caps, I don't see from the picture that any other part changes were made. Can anyone tell me why the LDO isn't working like it should? For now, I have put the 78L05 back.


Here is my early version of the new Tester with some modifications.
The 10-pin ISP header is soldered, but one side of the frame must be cut out
to match the room left for the header.
The original potentiometer has been replaced to a exemplar with higher resistance
(10k) to save power.
Two blocking capacitors of 100nF each are additionally mounted near the ATmega.
The D1 zener diode is replaced by a precision voltage reference like LM4040AIZ2.5 .
If you don't have a precision voltage reference, you should remove the zener diode at least.
I had also replaced the original 78L05 regulator by my preferred MCP1702-5002 regulator,
because this regulator can also save quiescent current.
Regards, Karl-Heinz
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 22, 2014, 02:06:59 am
Is it also getting warm? Whenever a regulator does this to me, it's usually because it doesn't like the capacitors on its input or output. The great thing about 78L05 is that it's stable under the same conditions that would make other ones oscillate like crazy. HTH
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 22, 2014, 03:16:40 am
I bought the graphical LCD version from EBay (fish...)

I think I bought the same thing. This is what I ordered: http://www.ebay.com/itm/111329306664. (http://www.ebay.com/itm/111329306664.) What I received has the same circuit board, but the LCD is mounted a bit differently. I'm pretty sure that it is an ST7565, as the backside of the display board is marked with SPI signal names.

I already have one of the 16x2 LCD testers that I bought some time ago. Although listed as having an ATmega328P, it actually has an ATmega168 (SMD). The part number was sanded off and the lock bits were set (jerks). After soldering on an ICSP header, I manged to erase the chip and update it to 1.11k.

So, I decided to go for broke and see about updating the graphic version that I just got. It also needed a header (out the back of the board for the correct pinout), but this one did not appear to be locked. I made a backup of the firmware, then flashed the ST7565 1.11K firmware.

Things didn't go so well this time. I do get text on the screen, but it looks mirrored and upside down. It also looks too large and ghosted. Obviously, there are some differences between the standard firmware and/or hardware and what this Chinese guy made. I can't go back to the original firmware, because AVRDUDE says the file is corrupt.

If anyone figures out how to update this board, please let me know.
Title: Re: $20 LCR ESR Transistor checker project
Post by: johnh on December 22, 2014, 05:29:56 am
This listing (111329306664.) has been removed, or this item is not available.

        Please check that you've entered the correct item number
        Listings that have ended 90 or more days ago will not be available for viewing.



Do have a image of the item you bought
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 22, 2014, 05:36:27 am
The period shouldn't be part of the link:

111329306664 (http://www.ebay.com/itm/111329306664)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 22, 2014, 05:37:56 am
I probably mis-copied the item number. I attached a picture. It doesn't show in the Preview. Hopefully you can view it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 22, 2014, 05:41:07 am
The period shouldn't be part of the link:

111329306664 (http://www.ebay.com/itm/111329306664)

Thank you. My mistake. The listing of the one with the blue circuit boards is where I ordered from. What I received has red boards, as the picture I just posted. What I have has the blue backlight and white characters. From what I read here, that is supposed to be newer than the one with the green LCD.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 22, 2014, 05:43:35 am
Is it also getting warm? Whenever a regulator does this to me, it's usually because it doesn't like the capacitors on its input or output. The great thing about 78L05 is that it's stable under the same conditions that would make other ones oscillate like crazy. HTH

I didn't think about checking the temperature when I had the LDO installed. I have since put a 78L05 back. I may leave it this way for a while. I have other projects that need attention. I did replace the voltage reference, so that should be an improvement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 22, 2014, 12:57:37 pm
I replaced the zener with the 2.5V reference and everything works OK. When I replaced the 78L05 with the recommended LDO regulator, the board still works, but now reports that the 9V battery is low, at 7V. Yes, I did take into account the different pinout between parts.

Have you checked the battery voltage and Vcc (+5V) with a DMM?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 22, 2014, 01:11:42 pm
Things didn't go so well this time. I do get text on the screen, but it looks mirrored and upside down. It also looks too large and ghosted. Obviously, there are some differences between the standard firmware and/or hardware and what this Chinese guy made. I can't go back to the original firmware, because AVRDUDE says the file is corrupt.

If the display got any ID you could try to get the datasheet and check if the display needs some additional or special setup. The problem with the modified clones is that the firmware isn't published. Therefore I recommend to stay away from clones with graphic displays unless they are fully ST7565 compatible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on December 22, 2014, 03:15:12 pm
The period shouldn't be part of the link:

111329306664 (http://www.ebay.com/itm/111329306664)
The first picture shows that this tester does not give the user a correct representation of the transistor under test.
It shows a BJT transistor but the Vf is 1.27 volts.  This indicates a darlington transistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 23, 2014, 06:05:59 am
I replaced the zener with the 2.5V reference and everything works OK. When I replaced the 78L05 with the recommended LDO regulator, the board still works, but now reports that the 9V battery is low, at 7V. Yes, I did take into account the different pinout between parts.

Have you checked the battery voltage and Vcc (+5V) with a DMM?

No, I didn't think of that when I had the LDO installed. I'll check the voltage when I put an LDO back in, later.

Title: Re: $20 LCR ESR Transistor checker project
Post by: JacquesBBB on December 29, 2014, 11:24:04 pm
So, I decided to go for broke and see about updating the graphic version that I just got. It also needed a header (out the back of the board for the correct pinout), but this one did not appear to be locked. I made a backup of the firmware, then flashed the ST7565 1.11K firmware.

Things didn't go so well this time. I do get text on the screen, but it looks mirrored and upside down. It also looks too large and ghosted. Obviously, there are some differences between the standard firmware and/or hardware and what this Chinese guy made. I can't go back to the original firmware, because AVRDUDE says the file is corrupt.

I have bought a slightly different one, that has the advantage of having a atmega328p on a socket
http://www.ebay.fr/itm/181534623115?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 (http://www.ebay.fr/itm/181534623115?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)
I even put a zif support so I can change the processor  easily. I have thus saved the original 328p and
I am playing with a new one and my programmer. 

I have  dowloaded the software from
http://www.mikrocontroller.net/svnbrowser/transistortester/ (http://www.mikrocontroller.net/svnbrowser/transistortester/)

and I am trying to configure the Makefile for my board, but with moderate success up to now.
I have been using  several options, but the one that  seems to work is mega328_st7565
although I have   the same problem of display :  reverse screen, with large and faded fonts.

The screen is marked 12864-1602_V1.1 (2014.08.01)  from EZM Electronics Studio

Can anybody help ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: JacquesBBB on December 30, 2014, 12:00:11 am
Some progress this will be useful for mojoe :

In the makefile, one  needs to comment the two line s

#CFLAGS += -DLCD_ST7565_H_FLIP=1
#CFLAGS += -DLCD_ST7565_V_FLIP=1

Also the font is better with

CFLAGS += -DFONT_6X8

I have still to correct the contrast

done with
LCD_ST7565_RESISTOR_RATIO = 5
instead of
LCD_ST7565_RESISTOR_RATIO = 4

 and to make it understand that the screen is much larger, or essentially to
add a new line at the end of each line.
Apart from that, it seems to work, with the proper graphics, although I have not fully tested it, and compared with the
original firmware.

Title: Re: $20 LCR ESR Transistor checker project
Post by: JacquesBBB on December 30, 2014, 01:29:34 pm
Here is an update on my experience in using the
mega328_st7565   firmware  from Karl-Heinz Kubbeler v.1.11k on a
ebay cheap ESR meter.

After the modification of the Makefile as I mentioned before,
the  display is OK, but different from the original.

The nice thing of the board I have, is that I could just squeeze a zif socket on the original one.
This was extremely useful for testing various versions of the firmware.

In the attached  pictures, you have in the first three pics the New firmware that I   uploaded,
and in the next two the original firmware display, which is also supposed to be 1.11k,
according to the seller.

The last picture show the setting of the zif socket.

As you see,  the font is the same, but there is a blank line spacing in the original firmware.
I did not find any option to add these blank lines, which makes the output nicer.
Does anybody knows what to do to add these lines, and in general to
make better use of the large LCD display ? 

On the opposite, the "show data" item is missing in the original firmware,
but the version is visible in the selftest : also 1.11k

The nice thing is that I will now be able to upgrade the firmware, and to calibrate the  meter which is a
large improvement with respect to my previous one based on an atmega168 SMD  (with sanded brand).


 
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 31, 2014, 05:41:45 am
Hey, thanks for posting. I'll have to try what you did on mine and see if it works. Good work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 31, 2014, 06:01:40 am
Since you still have the original firmware, could you read it and post it somewhere so I have a copy? As I mentioned before, what I read from the SMT chip on mine is somehow corrupt and I can't flash it back with avrdude.

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on January 02, 2015, 12:27:56 am
Some progress this will be useful for mojoe :

Thanks to your posting, I now have my Fish8840 tester working again. Some of my makefile settings are different than yours.

makefile options:

FLAGS += -DLCD_ST7565_H_OFFSET=4
CFLAGS += -DLCD_ST7565_H_FLIP=1
# CFLAGS += -DLCD_ST7565_V_FLIP=1
CFLAGS += -DFONT_6X8
CFLAGS += -DBAT_NUMERATOR=66 (I measured the battery voltage and it matches with the displayed voltage with this)

To get the double-spaced lines, look in the file lcd-routines.c:

Change:
lcd_set_cursor(1,0)
lcd_set_cursor(2,0)
lcd_set_cursor(3,0)

To:
lcd_set_cursor(2,0);
lcd_set_cursor(4,0);
lcd_set_cursor(6,0)

The only anomaly I have is that although 3 is the best LCD contrast value that works, it really is a bit too light. It seems as though I need a 2.5 or so. The original firmware had the screen contrast set higher.

Joe
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on January 02, 2015, 02:09:52 am
One more anomaly. The transistor symbol in the lower right corner of the display is too low. Part of it is cut off. I tried setting the line spacing back to single and it makes no difference. There must be another setting to position the symbol. I just have to find it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on January 02, 2015, 02:36:16 am
Here is an update on my experience in using the
mega328_st7565   firmware  from Karl-Heinz Kubbeler v.1.11k on a
ebay cheap ESR meter.

When you test a diode or cap, do you get a graphic symbol in the lower right for it, or do you get the character symbol on the first line? For transistors, I get the graphic symbol. For two-terminal devices, I get the character symbol.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JacquesBBB on January 02, 2015, 09:56:05 am
When you test a diode or cap, do you get a graphic symbol in the lower right for it, or do you get the character symbol on the first line? For transistors, I get the graphic symbol. For two-terminal devices, I get the character symbol.

For both the original and the  compiled firmware, I  have diodes, resistors, and capacitors graphics on the first line,
and transistors and mosfets with the graphic.

Thanks for  the lcd lines fix. It works, and now I have the same display as in the original firmware. I do not have to fix the battery voltage, as it is pretty close to the measure (8.6 instead of 8.7).

As you see in my pictures, the graphics is the same in the compiled firmware and the original one.

I believe that  the are some harware differences in the boards, and most probably mine is intended to be very
close to the original design. I did not check the values of the components, but it looks like.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 07, 2015, 06:24:30 pm
That board looks exactly like the one with 1602. They just slapped a large display on an old design, I think. If it comes with 10-microfarad aluminum caps, it might benefit from replacing those, but otherwise it does follow the original design fairly closely.

I can't quite make it out on the pictures, but I think the offset may need to be set to 0 instead of 4. This type of display benefits from larger fonts, in my experience, but I'd like to make the icons fit in with the larger font... Maybe I'll learn to do that someday.



By the way, I've got another puzzle. I have a coil that's about 7.1 Ohm as measured with a DMM. My TT measures the resistance as 7.1 Ohm correctly. Then I insert a resistor in series to the remaining test point. It measures the resistor correctly, but suddenly thinks that the coil is about 19 Ohm!  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 08, 2015, 12:07:16 pm
By the way, I've got another puzzle. I have a coil that's about 7.1 Ohm as measured with a DMM. My TT measures the resistance as 7.1 Ohm correctly. Then I insert a resistor in series to the remaining test point. It measures the resistor correctly, but suddenly thinks that the coil is about 19 Ohm!  |O

Is the second resistor about 19 - 7.1 = 11.9 Ohms? Does that happen also for any other two resistors?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 08, 2015, 06:05:34 pm
No, that would be too easy! It's 100 kilohm. Also tried with 500. Same result. Tried with two different testers, one with 1602 and one with 7565 display. Sometimes the coil's resistance is shown first, sometimes the other resistor's resistance is shown first, seemingly at random.

Seems to happen only with coils, but I don't have small value resistors to check at the moment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RedOctobyr on January 11, 2015, 11:46:16 pm
Whew, this is quite a thread! Read through the whole thing, though that doesn't mean I understood all of it. Tons of great info! Thank you to Karl-Heinz, madires, and everyone who has contributed to this amazing tool/project!

By the way, thank you to the people who mention something like a hardware difference, and then explain the ramifications of the difference :) Just saying that one has a crystal, or doesn't have a 2.5V reference, etc, doesn't tell some of us what that really means, or why it's good/bad. Those kinds of explanations are appreciated  :-+

I just ordered mine, I went with this one:
http://www.ebay.com/itm/251334183807?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/251334183807?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

It's supposed to have the M328 chip, on a socket. I don't know if it can take an ISP header. It has the 2-line display, which should help with firmware compatibility. It lists an 8MHz crystal.

Now for the embarrassingly-easy question (I'm new at all this). One thing I'd like to use it for is in-circuit ESR testing. So I'll need some kind of pointed probes which can also plug into the tester. Presumably into the ZIF socket. Is there anything that's recommended for that?

I'm sure this is incredibly basic, which is why it never even comes up. But I'd like to order other things I'll need, while this is being shipped. And normal multimeter probe bananas will be too fat to plug in, unless I cut their ends off. There is one version (the one with a case) which includes leads, but I don't see much discussion of them apart from that.

As I understand it, I should have an appropriate capacitor available for use during calibration. And I will need to re-read some things to better understand what would be needed to update the firmware (no idea what mine will have, but almost certainly an old version; the listing says 2013 software).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2015, 01:40:53 pm
Now for the embarrassingly-easy question (I'm new at all this). One thing I'd like to use it for is in-circuit ESR testing. So I'll need some kind of pointed probes which can also plug into the tester. Presumably into the ZIF socket. Is there anything that's recommended for that?

I'm sure this is incredibly basic, which is why it never even comes up. But I'd like to order other things I'll need, while this is being shipped. And normal multimeter probe bananas will be too fat to plug in, unless I cut their ends off. There is one version (the one with a case) which includes leads, but I don't see much discussion of them apart from that.

Maybe some multimeter probes soldered to a pin header matching the ZIF socket. Add some heat shrink and have fun.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2015, 03:24:03 pm
No, that would be too easy! It's 100 kilohm. Also tried with 500. Same result. Tried with two different testers, one with 1602 and one with 7565 display. Sometimes the coil's resistance is shown first, sometimes the other resistor's resistance is shown first, seemingly at random.

Seems to happen only with coils, but I don't have small value resistors to check at the moment.

Thanks! I'm able to reproduce that issue with the k-firmware. For a 1mH coil the difference is minimal but for a 15mH coil it's 142 Ohms (with a 1k and 100k resistor).

Update: The issue seems to occur if the resistance of the coil is < 10 Ohms.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 12, 2015, 09:10:07 pm
Thank you for looking into this. BTW, unrelated, but might be something for Karl-Heinz to look at for the next update, there's a new (I think) icon for bipolar transistors with a protection diode. If I use a transistor without a diode and add a diode to it in the "wrong" direction, this is reflected inline, but the icon remains the same. Kind of strange to look at. Not that it's a normal condition, of course, but still...

It's supposed to have the M328 chip, on a socket. I don't know if it can take an ISP header. It has the 2-line display, which should help with firmware compatibility. It lists an 8MHz crystal.

Now for the embarrassingly-easy question (I'm new at all this). One thing I'd like to use it for is in-circuit ESR testing. So I'll need some kind of pointed probes which can also plug into the tester. Presumably into the ZIF socket. Is there anything that's recommended for that?

I'm sure this is incredibly basic, which is why it never even comes up. But I'd like to order other things I'll need, while this is being shipped. And normal multimeter probe bananas will be too fat to plug in, unless I cut their ends off. There is one version (the one with a case) which includes leads, but I don't see much discussion of them apart from that.

As I understand it, I should have an appropriate capacitor available for use during calibration. And I will need to re-read some things to better understand what would be needed to update the firmware (no idea what mine will have, but almost certainly an old version; the listing says 2013 software).
That one looks just like the one I have, seems pretty popular. It has no ISP header nor pads for it. But the chip is removable, so the header is not really needed all that much if you're just going to update the firmware once in a blue moon.

I don't see why someone would buy a "naked" version now that ones with a case are available. I bought it for the sole purpose of mercilessly experimenting with the hardware, but if I needed one for just testing components, I'd get one with a case for sure. The one you mentioned is  the one with a blue case (http://item.taobao.com/item.htm?spm=a1z10.1-c.w4004-737437924.12.q4COnL&id=17620914059), right? I believe it's very similar internally to what you have ordered. A quick overview of what's available on the famous auction site has shown that these also might come with leads: Mega328 Transistor Tester Diode Triode inductor Capacitance ESR Meter LCR LED (http://www.ebay.com/itm/Mega328-Transistor-Tester-Diode-Triode-inductor-Capacitance-ESR-Meter-LCR-LED-/281549885699?pt=LH_DefaultDomain_0&hash=item418dae5103) and ATmega328 version inductor-capacitor ESR Transistor tester meter Digital lcd (http://www.ebay.com/itm/ATmega328-version-inductor-capacitor-ESR-Transistor-tester-meter-Digital-lcd-/111553911569?pt=LH_DefaultDomain_0&hash=item19f9219b11). If I were to get one for everyday use, it would probably be this: M328 transistor tester can be measured LCR / transistor / MOSFET / SCR (http://www.ebay.com/itm/M328-transistor-tester-can-be-measured-LCR-transistor-MOSFET-SCR-/321595001808?pt=LH_DefaultDomain_0&hash=item4ae08e4bd0) (spelling and grammatical errors are courtesy of the sellers). It can take leads and also has the frequency option. Doesn't seem to come with leads though.

This is not something I'd recommend someone to do, but for quick makeshift test leads that fit into a ZIF socket I use flexible breadboard jumpers (http://www.amazon.com/Solderless-Breadboard-Jumper-Cable-Qty75/dp/B0043LTD3M).

I'd go with what madires (https://www.eevblog.com/forum/profile/?u=25360) advised for now. I would try to use leads that are as short as possible to minimize stray capacitance and lead resistance.

As for the capacitor, as I understand it, your only concern should be that it's above 100nF and has the least possible amount of leakage. Nothing too special is required for calibration, which is one of the reasons I like this project so much.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RedOctobyr on January 13, 2015, 12:59:30 am
madires, hapless, thank you both for the feedback. hapless, that last tester you linked to (with frequency functions) looks pretty nice. But I'll start with what I ordered, and see how that works for me. I'm guessing it'll be fine for my current purposes.

If I may ask, since mine is apparently like yours, are there modifications that I should plan on doing to it? I don't know if this design is missing something important. ESR/capacitance checking is what I forsee for uses at the moment, for trying to help troubleshoot issues.

I'll probably try multimeter leads to start, maybe cutting down their length if needed. The mention of flexible breadboard jumpers made me realize maybe I could use some similar small cables I have sitting around, thanks  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Halfdead on January 13, 2015, 07:34:40 am
Has anyone else had their tester die?
 :-BROKE

I think the ATMEGA328P in my unit died, the unit draws over 200mA when turned on and the display doesn't power on properly, the display goes to nearly full brightness when you power the unit on and then dims very low nearly instantly after.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 13, 2015, 01:00:54 pm
Update: The issue seems to occur if the resistance of the coil is < 10 Ohms.

I've discussed that with Karl-Heinz. The cause of the issue is the ESR measurement which is also used to measure resistances less than 10 Ohms in the k-firmware. The measurement method doesn't deliver valid results for inductors. If an inductor is detected the low resistance measurement is skipped. And since the check for inductors is performed only if one single component is tested, an inductor and a resistor connected to all three probes are detected as two resistors. In that case the low resistance measurement is run and you'll see the wrong resistance value for the inductor. The m-firmware uses a different method for low resistance measurements (dedicated function) which also runs fine for inductors, but I don't know if Karl-Heinz will add it to the k-firmware (flash size constraints).
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 13, 2015, 05:02:59 pm
Interesting. So, if I use a low-value wirewound potentiometer and insert all three leads, it will not show the correct results? This is definitely something to be aware of.

How does your function compare to the ESR one in terms of resolution and accuracy? If he decides not to include it, I might just have to make a franken-firmware. I don't compile with UART and I enable the use of EEPROM, so should have enough memory for the modification. I'm also trying to figure out why the code for the frequency generator (function switch_frequency) is so lengthy while looking somewhat repetitive. Maybe folding it into a smaller function will free up some flash, too...

Has anyone else had their tester die?
 :-BROKE

I think the ATMEGA328P in my unit died, the unit draws over 200mA when turned on and the display doesn't power on properly, the display goes to nearly full brightness when you power the unit on and then dims very low nearly instantly after.
Is anything getting hot on the board? If the chip is removable, remove it and power on the unit. If it behaves the same way without the chip, check the regulator and its output capacitor.

If I may ask, since mine is apparently like yours, are there modifications that I should plan on doing to it? I don't know if this design is missing something important. ESR/capacitance checking is what I forsee for uses at the moment, for trying to help troubleshoot issues.
It should work well out of the box, but I would advise replacing those 10-microfarad capacitors with something better. On the output side of the regulator you may want to put a tantalum capacitor of about twice as much capacitance, and the one blocking the battery can be about 10 times higher. Mine are 47 and 100 respectively, but 47 might be a little overkill. This will improve the stability of the regulator and make the results a little more repeatable. Other than that, all modifications are totally optional. I like having a 2.5V voltage reference and a 1nF cap on the aref pin. Neither seems to affect the numbers too much for me though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Halfdead on January 14, 2015, 09:23:11 am
I removed the ATMEGA328P and the current drawn goes down to about 7 mA which seems reasonable and the display is now at full brightness but displaying gibberish as to be expected.


I think it's just a dead ATMEGA328P, but I've no idea how it died or where to get replacement firmware that's compatible with this unit.

Has anyone else had their tester die?
 :-BROKE

I think the ATMEGA328P in my unit died, the unit draws over 200mA when turned on and the display doesn't power on properly, the display goes to nearly full brightness when you power the unit on and then dims very low nearly instantly after.
Is anything getting hot on the board? If the chip is removable, remove it and power on the unit. If it behaves the same way without the chip, check the regulator and its output capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2015, 12:35:37 pm
Interesting. So, if I use a low-value wirewound potentiometer and insert all three leads, it will not show the correct results? This is definitely something to be aware of.

The displayed values for the potentiometer will be fine. Only if you add an inductor of a few mH or more the tester will show the wrong resistance value for that inductor. But if you got just the inductor connected to the probes the resistance diplayed will fine again.

How does your function compare to the ESR one in terms of resolution and accuracy? If he decides not to include it, I might just have to make a franken-firmware. I don't compile with UART and I enable the use of EEPROM, so should have enough memory for the modification. I'm also trying to figure out why the code for the frequency generator (function switch_frequency) is so lengthy while looking somewhat repetitive. Maybe folding it into a smaller function will free up some flash, too...

The resolution is the same (0.01 Ohms) and accuracy seems to be about the same also. If you use the optional functions I'd recommend to add a rotary encoder for a more convenient UI. In case you got a tester with text display you can run the m-firmware anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 14, 2015, 05:24:45 pm
Thanks, I actually have a couple of encoders lying in front of me just asking to be connected. Looks like the test button's behavior is automatically modified when the resistor dividers are connected.  8)

TBH, I don't remember what happened. I tried the m-firmware, liked it, then found something that I couldn't live without in k-firmware and switched back.  :-// That was before I even started reading the forums. The problem is probably long gone by now.

I think I'm going to try to lift the function from m-firmware and transplant it into k (unless K.-H. beats me to it, which he probably will if he decides to use it). I wonder if there's a way to contribute back without the use of a versioning system? Maybe by posting diff files somewhere?

Interesting. So, if I use a low-value wirewound potentiometer and insert all three leads, it will not show the correct results? This is definitely something to be aware of.

The displayed values for the potentiometer will be fine. Only if you add an inductor of a few mH or more the tester will show the wrong resistance value for that inductor. But if you got just the inductor connected to the probes the resistance diplayed will fine again.
I see. Thanks for clarifying.

I removed the ATMEGA328P and the current drawn goes down to about 7 mA which seems reasonable and the display is now at full brightness but displaying gibberish as to be expected.


I think it's just a dead ATMEGA328P, but I've no idea how it died or where to get replacement firmware that's compatible with this unit.
This would mostly depend on the display and layout of the board. How about attaching pictures of what you have?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mafiawarsfourlife4 on January 21, 2015, 05:48:25 pm
In case anyone is interested in the graphics versions: they are described and sold within China on a Web site in Chinese only:
http://fish8840.taobao.com/ (http://fish8840.taobao.com/) I prefer to open it in Google Chrome, which offers to translate it automatically, or on a right-click. I don't know whether the many sources of these devices buy from fish8840 (in which case they'd be all be of equal quality) or make their own copies.

Presumably fish8840 is the originator of the Chinese hardware versions (although they themselves may be imitated!), and weiweitm adapted the software. The reason for production of a graphics version given is that a text-only display in Latin characters is difficult for Chinese people, which makes sense; there are traditional and simplified Chinese, and English-language versions. There are two versions, an older one with a green display, and a later one with a slightly larger blue display; both are sold, with the blue one a little more expensive. The pictures don't show a crystal visible on the board; it could be there but hidden. As far as I can tell the later board was released in March 2014; the only software appears to be weiweitm's version 2.1 (with no mention of providing source code). I don't know if there is any provision at all for software updates (socketed chip, header, any intention to produce downloadable updates). There is a picture of an elegantly cased version, branded Yiwanjia, but no indication (such as price) that it exists.

Foreigner Markus F is acknowledged. The translation is difficult to understand in detail; I think Translate's "shelves without shell" are uncased boards!

Web pages of the two hardware versions (Chinese):
Larger screen, blue, backlit 25/3/2014, software shows as 2.1 on pictures:
http://item.taobao.com/item.htm?spm=a1z10.5.w4002-2323427594.16.IhvBUf&id=36323329572 (http://item.taobao.com/item.htm?spm=a1z10.5.w4002-2323427594.16.IhvBUf&id=36323329572)
Smaller green graphics screen version:
http://item.taobao.com/item.htm?spm=a1z10.5.w4002-2323427594.19.IhvBUf&id=37659767669 (http://item.taobao.com/item.htm?spm=a1z10.5.w4002-2323427594.19.IhvBUf&id=37659767669)
i need to repair this transistor tester and i dont know where to start?any help would be great.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RedOctobyr on January 23, 2015, 01:50:44 am
I just ordered mine, I went with this one:
http://www.ebay.com/itm/251334183807?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/251334183807?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

...
And I will need to re-read some things to better understand what would be needed to update the firmware (no idea what mine will have, but almost certainly an old version; the listing says 2013 software).

Mine arrived today, ordered 11 days ago. I'm pleasantly surprised, I was expecting it to take longer.

Another nice surprise, it has FW 1.11k. That version appears to be dated January 5th, 2015, from what I can see, and my unit was ordered about a week after that. I'm glad they're at least loading current firmware, so I don't have to worry about doing that right away.

I tested some capacitors and resistors that I had sitting around, very cool! A 100 Ohm 2% resistor measured as 98.7 Ohms. I did the calibration routine, using a 10uF capacitor. The readings didn't seem to change meaningfully after the calibration; perhaps it was calibrated before shipping.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on January 23, 2015, 02:20:27 am
Is there anywhere FW 1.11k can be downloaded?

Never mind, found it. Currently 1.16
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 23, 2015, 11:49:35 am
Is there anywhere FW 1.11k can be downloaded?
1.11k is the current version under development and can be found at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) (click "Download GNU tarball" at the bottom).

Never mind, found it. Currently 1.16
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)
That's 1.16m and it supports text displays only. The UI is a little bit different, some tests and measurements are done in a different way, functionality is nearly the same and it offers a few small extras, like detection of TRIACs' MT1 and MT2.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on January 23, 2015, 04:34:25 pm
I've ordered one of the text versions, the graphics seemed unnecessary.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rob77 on January 23, 2015, 07:45:53 pm
had one atmega644 in DIP40 around...got no other real use for it.. so I’ve built the tester myself with that atmega644 and lm336-2.5 reference and a mc34063 step up to 30V + 1mA current source  for zener testing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: malch on January 28, 2015, 03:33:57 am
I got the one someone recommended. It works with USB power and no battery. [I had to try it right away]

https://www.youtube.com/watch?x-yt-ts=1422327029&x-yt-cl=84838260&v=UbOMqA2AOIk&feature=player_embedded (https://www.youtube.com/watch?x-yt-ts=1422327029&x-yt-cl=84838260&v=UbOMqA2AOIk&feature=player_embedded)


I think I should have bought one with a 9 volt battery and larger screen, now that I have it in my hand.

Does this use a rechargeable lithium battery?

edit jan 29: Seller replied yes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pixel26 on January 28, 2015, 03:19:45 pm
Hi,

I just buy a transistor tester 328p:

(http://image.noelshack.com/fichiers/2015/05/1422457535-giuiiu.png)

And i read earlier in this topic, it was possible to flash with this firmware "mega328_st7565" for a better accuracy.

 I really do not know where to enter in Avrdude, can you help for for the fuse parameters please ? I use a Usbasp.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pixel26 on January 29, 2015, 10:25:32 pm
Hi,

I found what I needed:

Hfuse: 0xD9
Efuse: 0xFC
Lfuse: 0xF7

But for efuse my tester not want this new value, i leave on 0x04.

I also had to change the makefile. My screen is displayed nothing, the values that I changed:


-For blank screen:

LCD_ST7565_RESISTOR_RATIO = 5
CFLAGS += -DFONT_6X8

-For the display back normal to 180 ° I desactivate:

CFLAGS += -DLCD_ST7565_H_FLIP=1
CFLAGS += -DLCD_ST7565_V_FLIP=1

-And for the measurement of the battery voltage, i change value "133" by "66":

CFLAGS += -DBAT_NUMERATOR=66


I noticed that the tester with the backlight consume +- 115 ma !!!  And cutting its power supply consume +- 15ma, much better  :-+


That is, if it can help others.


Ps: sorry for my bad english, I hope so this is a minimum comprehensible  :)




Title: Re: $20 LCR ESR Transistor checker project
Post by: Mr Smiley on January 30, 2015, 05:05:55 am
Hi,

I found what I needed:

Hfuse: 0xD9
Efuse: 0xFC
Lfuse: 0xF7

But for efuse my tester not want this new value, i leave on 0x04.


I had the same confusing problem with the efuse, asking it to be set to 0xfc gave an error saying it was now showing 0x04.

I went to one of the many on line fuse calculators and put in 0xfc which gave an indication of which fuses where being set. I then put in a value of 0x04 and the result was that the same fuses were set for for 0x04 as they were for 0xfc  :-/O

 :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: jimmc on January 30, 2015, 03:27:06 pm
The problem is that the five high bits which are not implemented are being set to '1' by the fuse calculator and read as '0' by the AVRDude.
AND either with 07 (0000 0111) to mask off the unused bits and they're the same

xxxx x100
1111 0100     FC
0000 0100     04

Jim
Title: Re: $20 LCR ESR Transistor checker project
Post by: Danielw on January 30, 2015, 04:10:13 pm
What would normally blow up if you by accident connect a charged cap on this? I thought it was the atmega but I tried connect 3,3v direcly to ISP connector and it started up. It is the FISH8840 version I've got.

It does not start up with 9v connected.

Edit: It just started up by itself! :o But stuck at 'testing' and shuts off after only 1-3 sek. Hmmm...

Best regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 31, 2015, 02:17:13 pm
What would normally blow up if you by accident connect a charged cap on this? I thought it was the atmega but I tried connect 3,3v direcly to ISP connector and it started up. It is the FISH8840 version I've got.

It does not start up with 9v connected.

The Vcc pin of the ISP header is directly connected to the circuit's Vcc. Please see the schematic in Karl-Heinz' documentation at http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/) (click "Download GNU tarball" at the bottom).
Title: Re: $20 LCR ESR Transistor checker project
Post by: mmatic on February 02, 2015, 10:15:38 am
Which one is best buy right now?

This one on the link below?
http://www.ebay.com/itm/251334183807?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/251334183807?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pukje on February 02, 2015, 01:13:10 pm
This weekend i installed winavr, and compiled the source. My hex output has a larger size,
I tested the makefile in the mega328 directory.
The precompiled version is 65783 bytes, my compiled version is 77859 bytes.
( I used the make all option in the programmers notepad).

After that i compiled the software on my centos machine, and that hex file was
also bigger then the original, this hex file was 77622 bytes.
My tester is in the mail, i orderd him last week, so i can't test the hex file
at this moment.

What i'm a doing wrong ???

Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on February 03, 2015, 03:40:29 am
Which one is best buy right now?

This one on the link below?
http://www.ebay.com/itm/251334183807?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/251334183807?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

I ordered from this listing (http://www.ebay.com/itm/171467739124?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT).

It was packed well, shipped quickly and arrived in Seattle less than a week after I ordered it. Its based on the same EZM Studios board as the one you linked to, but fitted with a larger graphical display, which, as I understand it, is supported by the mainline firmware. I haven't tried  yet, but I have another ATMega on the way to experiment with.

I think its advantages of the EZM Studios variants  are that it is relatively close to stock hardware and software, with the hidden modes already enabled, has a socketed MCU, and most of the components are through-hole for easier tweaking. I think the main downside is that the SMD contact pattern isn't great, and some people have suggested replacing the caps.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JacquesBBB on February 03, 2015, 04:48:32 pm
@eas

It seems that you have the same board as mine.
In this case, you can compile the  setting of the Makefile  that is described  in my previous posts
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/799/
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/800/
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/801/

and in mojoe  post to get the screen right
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/804/

In summary   :

In the makefile,

comment the two line s
#CFLAGS += -DLCD_ST7565_H_FLIP=1
#CFLAGS += -DLCD_ST7565_V_FLIP=1

The font is better with
CFLAGS += -DFONT_6X8

Correct the contrast with
LCD_ST7565_RESISTOR_RATIO = 5
instead of
LCD_ST7565_RESISTOR_RATIO = 4

and  To get the double-spaced lines,  in the file lcd-routines.c:

Change:
lcd_set_cursor(1,0)
lcd_set_cursor(2,0)
lcd_set_cursor(3,0)

To:
lcd_set_cursor(2,0);
lcd_set_cursor(4,0);
lcd_set_cursor(6,0)

Jacques
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on February 03, 2015, 07:47:49 pm
@eas

It seems that you have the same board as mine.
[...]

Yes, thanks! I've already made note of all those posts, but it will be very helpful for others. 

Someone contacted me privately asking about how the GM328 compared to other versions I tried. I'm part way through editing a video and blog post on just that topic, but I thought I'd add a little more here:

That meter is my favorite of the three I've tried. In casual inspection, it seems to correctly identify every component I've tried, where as the others I tried have had trouble with some depending on the orientation.

I also tried the largest screen Fish8840 version, and this 91Make version (http://www.ebay.com/itm/261457669748?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT). In retrospect, the largest screen is pointless, in my opinion, and the graphics for components are too "heavy," which makes them hard to make sense of, a problem for the diagrams of simple BJTs and even more so small signal MOSFET.

I like the graphics/ui on the 91Make version best of all, but the firmware seems somewhat dated, doesn't have the full feature set enabled, and the hardware isn't hack friendly -- all surface mount, and to make use of, what I assume are the holes for the programming header, will require either pogopins, or detaching the LCD mounted directly to the PCB.

I plan to compile the latest open source firmware and install it on the Fish8840 tester, taking advantage of what Moejoe learned.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 03, 2015, 10:33:01 pm
I also tried the largest screen Fish8840 version, and this 91Make version (http://www.ebay.com/itm/261457669748?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT). In retrospect, the largest screen is pointless, in my opinion, and the graphics for components are too "heavy," which makes them hard to make sense of, a problem for the diagrams of simple BJTs and even more so small signal MOSFET.
The firmware that you compile will have considerably "lighter" graphics. As for the value of the graphical screen, there are at least two advantages: You can choose any size font (try CFLAGS += -DFONT_8X16 if you need glasses to read the screen), and you can use any character set, which becomes a huge issue with text displays that have no international characters (I want to give one of these as a gift to someone who speaks no English and would have to bend over backwards to get a 16x2 display that supports the characters from the right alphabet).
Title: Re: $20 LCR ESR Transistor checker project
Post by: coromonadalix on February 16, 2015, 11:33:57 pm
noob questions

Under Windows 8.1 x64     how can i compile the makefile,  i know nothing about this ???  what softwares do i have to install, WinAvr ? AvrDude ? Atmel studio ?

i have a atmega8 based tester, the first post image model ...   (avr rc crystal), updated to an mega328 model with 16x2 lcd  with the 1.11k trunk / mega328 section   works ok

i have read a lot of this thread  ... 

Wanted to use the 1.16m version, (since its supposed to be text only version),  but it stalls when displaying  zenner voltage / something ??? display show 16.5 volts, the button powers up the tester,  but it doesn't shutdown unless i remove the 9v cell


Found this : http://www.avrtester.tode.cz/index.php?p=firmware (http://www.avrtester.tode.cz/index.php?p=firmware)    already compiled hex and eep files   may help you guys
Title: Re: $20 LCR ESR Transistor checker project
Post by: samnmax on February 17, 2015, 11:21:58 am
Just a warning for anyone buying one of those chinese clones, the one that says "MTester V2.07" "By Efan &HaoQixin". I bought one from ebay for 15€, and it didn't work very well, it was slow and crashed with some components. Poking around with the scope I found that the crystal oscillator was not used!  :o

I soldered the ISP pins and connected to the Bus Pirate, avrdude said ATmega328P low fuse was 0x62 (default value). That means: "use internal RC oscillator" and "divide clock by 8"  :palm:

I tried to change the fuse but it was locked. I had to extract a copy of the flash and eeprom, erase the chip, set the fuse (I think I used 0xF7) and upload eeprom and flash again.

Afterwards, it worked fine! Somebody must have forgotten to program the fuse. Other than that I think it's very useful for its price.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2015, 01:24:49 pm
Under Windows 8.1 x64     how can i compile the makefile,  i know nothing about this ???  what softwares do i have to install, WinAvr ? AvrDude ? Atmel studio ?
The Makefile is used by the 'make' tool to build the firmware, it's some kind of special script. Atmel Studio supports external Makefiles (see GCC Project options and configuration tab).

Wanted to use the 1.16m version, (since its supposed to be text only version),  but it stalls when displaying  zenner voltage / something ??? display show 16.5 volts, the button powers up the tester,  but it doesn't shutdown unless i remove the 9v cell
To exit the m-firmware's zener tool please push the test button twice (two short presses). There's a readme file in the source package explaining the differences to the k-firmware including the UI.

BTW: 1.17m was realeased two days ago (several minor improvements and fixes).
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 18, 2015, 01:16:12 am
[...]I had to extract a copy of the flash and eeprom[...]

Would you mind sharing them? I'd like to try this firmware on my EZMStudio device. Really wish they'd publish the sources.
Title: Re: $20 LCR ESR Transistor checker project
Post by: samnmax on February 18, 2015, 07:10:12 pm
[...]I had to extract a copy of the flash and eeprom[...]

Would you mind sharing them? I'd like to try this firmware on my EZMStudio device. Really wish they'd publish the sources.

No problem, here they are.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 19, 2015, 05:04:54 pm
Much appreciated, thank you. From the looks of it, I am not the only one interested in them. I did a quick test and the firmware seems to work (shuts down the tester because the voltage is too low), but I get nothing on the screen, so it will need some modifications  :-/O, which, unfortunately, I won't be able to get started on for at least a month. If I manage to get this firmware to work on my tester, I will post the changed files.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gtroc71 on February 23, 2015, 07:47:09 pm
Could this device be run from an A23 12v battery?
Would like to make as compact as possible
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: JacquesBBB on February 23, 2015, 08:05:43 pm
Could this device be run from an A23 12v battery?

As there is a 5V linear regulator on these boards (AS1117 5.0 V on mine), it will not be very efficient
to power it with 12V. Everything above 7V is wasted.
9V is much more adapted.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 23, 2015, 08:11:00 pm
Could this device be run from an A23 12v battery?
Would like to make as compact as possible

I think so, but that battery won't last long (about 1/10 of a 9V one). And you should disable the LCD backlight.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gtroc71 on February 24, 2015, 02:02:39 am
Thank you so much Jacques and Madires.
Appreciate your fast response
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on February 24, 2015, 12:23:33 pm
Wow,
Looks like I have been slacking here. And a lot of catching up to do. Had forgotten all about this thread.
I have 2 of these now but one is dead. Maybe I will have a go at learning to update the firmware in mine and repairing the dead one.
So much to go back and read |O
I did not even know about the self calibrate lol.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on February 25, 2015, 03:57:37 pm
This was my first one I purchased.  And my first fail  |O
While testing some 100uf caps at 350 volts one of the caps did not get enough discharge time. When I connected the test leads the tester failed to come on. At least this is what I think happened.

(http://gokarters.com/smf/index.php?action=dlattach;topic=2454.0;attach=1541;image)

In the pic you can see a programmer I purchased a few months back and have yet to use it.
So I think my first attempt is to grab the schematic of this tester and install a header on the board.
I will attempt to communicate with the processor.

Been a long time (1990) since I have even attempted to read and program Atmel chips.  And even then it was a complete different beast back then.
At least this may give me a chance to learn a few things.

(http://gokarters.com/smf/index.php?action=dlattach;topic=2454.0;attach=1543;image)


As said in my above post I have a lot of catching up to do. And a lot of back reading. If anyone would like to give some pointers I am all ears :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on February 25, 2015, 06:23:56 pm
Well perhaps I was wrong about the controller being dead. After installing the pin header I was able to read the contents from the Atmega 168 chip.

After doing this I noticed something that was not happening before.  When ever I connected the battery to the device and hit the test button nothing happened. No display no red LED.
But now when I hit the test button for a couple of seconds I get a message on the LCD.

"BAT 4.8V empty"

I know my battery is good and test at 9 volts. So I but my DMM across the battery leads and when you hit the test button the voltage drops from 9 to 4 volts.

Looks like I need to check some on board components and see if any are failing.

(http://gokarters.com/smf/index.php?action=dlattach;topic=2454.0;attach=1545;image)

Perhaps I should had started another thread instead of tying this one up.


Edit to say, looks like I can read the chip but when I programmed the chip I just get a black bar now when I press the test button.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 26, 2015, 10:42:25 am
I did a quick test and the firmware seems to work (shuts down the tester because the voltage is too low), but I get nothing on the screen, so it will need some modifications  :-/O, which, unfortunately, I won't be able to get started on for at least a month. If I manage to get this firmware to work on my tester, I will post the changed files.

Looks like I won't be doing that after all. Had a little time on my hands and tried it out. The firmware is for strip-grid layout, which is not a problem, but the way it displays information seemed to look good from the screenshots, but up close and personal, I didn't like it at all. So I see no reason to try hacking it. On the other hand, I like the fact that they tried to use the screen in a more logical way for a graphical LCD. Something to think about when I actually get to do some coding.

Markus, Karl-Heinz, neither of you answered previously. If I make changes, is there a way to submit them to you without the use of SVN?

Edit to say, looks like I can read the chip but when I programmed the chip I just get a black bar now when I press the test button.

Does it turn off as soon as the button is released?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 26, 2015, 11:00:42 am
Markus, Karl-Heinz, neither of you answered previously. If I make changes, is there a way to submit them to you without the use of SVN?

Send them directly to Karl-Heinz via email ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on February 26, 2015, 12:03:54 pm


Does it turn off as soon as the button is released?
Yes, The string of bars are only present while holding the test button.
As said before this is my first attempt at programming so this is a new learniing curve for me. I am using Extreme AVR burner and dont think I am doing it right. I read something in the "testers" manual about having to set fuse bytes. So with that I am sure I am doing something wrong.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 27, 2015, 12:51:09 am
Send them directly to Karl-Heinz via email ;)

Will do, thanks!

Yes, The string of bars are only present while holding the test button.
As said before this is my first attempt at programming so this is a new learniing curve for me. I am using Extreme AVR burner and dont think I am doing it right. I read something in the "testers" manual about having to set fuse bytes. So with that I am sure I am doing something wrong.

You need to burn both flash and EEPROM for the tester to work. Looks like flash didn't get programmed that time. I wouldn't recommend messing with fuse bits until you figure out what most of them do.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on February 27, 2015, 01:18:43 am

You need to burn both flash and EEPROM for the tester to work. Looks like flash didn't get programmed that time.

I really think you are correct. Although the program says it is doing both somehow I do not think it is.

Quote
I wouldn't recommend messing with fuse bits until you figure out what most of them do.
Agreed and I have not touched those settings yet.

Back in the early 90's is the last time I have even played with any Atmels. And even then it was just a flash. So I am a complete noob when it comes to them. Since this tester is dead I thought perhaps this would be a good learning tool on the programming and learn a bit on how these testers work.  Even if I brick the chip I have the equipment and the knowledge to replace them.

I did notice something about the tester. The dead one has a 8MHz crystal on board and the new one has no crystal.  Both testers are identical other than the missing crystal.

Overthe next few days as time allows I plan to do a bit of reading up on AVR programming and watch a few YT vids.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 27, 2015, 01:19:46 pm
Quote
I wouldn't recommend messing with fuse bits until you figure out what most of them do.
Agreed and I have not touched those settings yet.
You need to set the fuse bits only once for a brand new ATmega. The Makefile includes the logic to select the correct fuse settings and to call avrdude. For the k-firmware you simply call 'make fuses', 'make fuses-crystal' or 'make fuses-crystal-lp' based on the clock source. For the m-firmware it's just a 'make fuses'.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on February 27, 2015, 06:57:25 pm

You need to set the fuse bits only once for a brand new ATmega. The Makefile includes the logic to select the correct fuse settings and to call avrdude. For the k-firmware you simply call 'make fuses', 'make fuses-crystal' or 'make fuses-crystal-lp' based on the clock source. For the m-firmware it's just a 'make fuses'.

Thanks for that bit of info madires.
Have not used avrdude yet. The only program I have tried is Extreme AVR. If I remember correctly I think avrdude is a dos base program. Atleast that is what I remember from Youtube.
I will try and do some more reading and YT vids over the short week end.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dadler on February 27, 2015, 07:06:31 pm
I got one of these boxes off ebay, but the cheap 2mm banana jacks drove me nuts. So I swapped in some shrouded 4mm jacks to be able to use my Fluke leads:

(https://dl.dropboxusercontent.com/s/mbps3ujuh50e5kz/mk-168_37.jpg)
(https://dl.dropboxusercontent.com/s/pxzez43m2bgt59j/mk-168_35.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on February 27, 2015, 08:54:40 pm
I have the same unit, where did you find the shrouded connectors?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on February 27, 2015, 10:38:04 pm
Thats looks pretty nice.
Thinking about ordering another one of these. Maybe that one.

Anyway been serching for more info on programing.  Read till my head hurts.
Sure wish there were some yourtube videos on this tester and programming it.  :-//
Know more about how would be nice, like do you program flash first or hex?  Have not been able to find this info. But I am sure I will  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: dadler on February 27, 2015, 10:48:37 pm
I have the same unit, where did you find the shrouded connectors?

I got them at the corner electronics store. They are just standard Pomona shrouded jacks. I can get the part number if you want.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 28, 2015, 11:22:55 am

Anyway been serching for more info on programing.  Read till my head hurts.
Sure wish there were some yourtube videos on this tester and programming it.  :-//
Know more about how would be nice, like do you program flash fist or hex?  Have not been able to find this info. But I am sure I will  ;D

It's programmed like any other ATmega via ISP. A quick search for "flashing atmega" at youtube lists a lot of videos. If you got an avrdude compatible ISP programmer and the make tool, a "make upload" will do the job.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 10, 2015, 03:53:43 am
If anyone has the latest m328p hex file for the M168 version (2x16 LCD) I'd appreciate it if you could attach a copy here.

edit: I found this, which contains a hex file. Is it the correct one?
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 10, 2015, 12:26:42 pm
If anyone has the latest m328p hex file for the M168 version (2x16 LCD) I'd appreciate it if you could attach a copy here.

edit: I found this, which contains a hex file. Is it the correct one?
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/)

If your tester has an ATmega168, please compile the firmware for the ATmega168. The pre-compiled ATmega328 firmware is too large for the ATmega168 (16kB flash). The ATmega328 got 32kB flash.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 10, 2015, 01:45:06 pm
It's got a 328p.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 10, 2015, 02:40:50 pm
It's got a 328p.

Ok, then it's the correct firmware. If you read the Makefile you'll see the enabled features.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 10, 2015, 05:56:51 pm
Will the hex file set the config fuses correctly? I'm also using an Arduino in arduinoisp mode to program a blank ATmega328p, any hint using avrdude would be appreciated.

I'm a PIC programmer, AVR's are alien to me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 10, 2015, 07:53:42 pm
Will the hex file set the config fuses correctly? I'm also using an Arduino in arduinoisp mode to program a blank ATmega328p, any hint using avrdude would be appreciated.

No, the hex doesn't include fuse settings. But you could use avrdude to set the fuses if required (actually just for a brand new ATmega). If the ATmega already runs a tester firmware you don't need to re-write the fuses.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 10, 2015, 08:40:12 pm
I ran the make file, it created a hex file. The fuse settings are still 00 00 00 so they're not getting set. I'm also not able to program the eeprom.
Quote
avrdude -c arduino -p m328p -P /dev/cu.usbmodem1411 -U flash:w:TransistorTester.hex:a -U eeprom:w:TransistorTester.eep:a

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.00s

avrdude: Device signature = 0x1e950f
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
         To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: reading input file "TransistorTester.hex"
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: writing flash (23832 bytes):

Writing | ################################################## | 100% 3.83s

avrdude: 23832 bytes of flash written
avrdude: verifying flash memory against TransistorTester.hex:
avrdude: load data flash data from input file TransistorTester.hex:
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: input file TransistorTester.hex contains 23832 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 3.06s

avrdude: verifying ...
avrdude: 23832 bytes of flash verified
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (14 bytes):

Writing | ################################################## | 100% 0.06s

avrdude: 14 bytes of eeprom written
avrdude: verifying eeprom memory against TransistorTester.eep:
avrdude: load data eeprom data from input file TransistorTester.eep:
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: input file TransistorTester.eep contains 14 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 0.03s

avrdude: verifying ...
avrdude: verification error, first mismatch at byte 0x0000
         0xff != 0x14
avrdude: verification error; content mismatch

avrdude: safemode: Fuses OK (H:00, E:00, L:00)

avrdude done.  Thank you.

Here's the TransistorTester I'm using.
(http://image4.pushauction.com/0/0/24b1a674-60a7-4d1b-80d4-58f42c015155/0f9bb578-8822-d4ce-7faf-de3d9eac290d.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 11, 2015, 09:40:16 am
I ran the make file, it created a hex file. The fuse settings are still 00 00 00 so they're not getting set. I'm also not able to program the eeprom.

Didn't you use the pre-compiled firmware? Anyway, a few posts ago I explained how to use the Makefile to set the fuses. But since you've got an error while verifying the EEPROM, there's another issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jimmc on March 11, 2015, 11:35:03 am
I've got the same (Banggood) version, the original fuse settings were...
L   0xFF
H   0xD9
E   0x04
LB   0x3F

I enabled  the brownout detection using...
(I know that there have been problems reported when using brownout detection but if the power glitches I'd prefer to know and fix it - No problems so far.)
L   0xFF
H   0xD9
E   0x07
LB   0x3C

I used the precompiled .hex & .eep files.

Jim
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 11, 2015, 01:20:49 pm
I've got the same (Banggood) version, the original fuse settings were...
L   0xFF
H   0xD9
E   0x04
LB   0x3F

I enabled  the brownout detection using...
(I know that there have been problems reported when using brownout detection but if the power glitches I'd prefer to know and fix it - No problems so far.)
L   0xFF
H   0xD9
E   0x07
LB   0x3C

I used the precompiled .hex & .eep files.

Jim

What version did you find? 1.17m?

Would you mind attaching the .hex & .eep files here?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 11, 2015, 05:36:33 pm
Would you mind attaching the .hex & .eep files here?

There's a nice site (http://www.avrtester.tode.cz/index.php?p=firmware (http://www.avrtester.tode.cz/index.php?p=firmware)) with firmware files for most versions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 12, 2015, 02:04:52 am
Thanks, I tried FW1.11M328 but it displays rubbish after the power on screen? Could this be because of incorrect fuse settings? Seems the Flash and eprom program fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 12, 2015, 11:48:54 am
Thanks, I tried FW1.11M328 but it displays rubbish after the power on screen? Could this be because of incorrect fuse settings? Seems the Flash and eprom program fine.

It's possible. The fuses set the clock source (internal RC, external quartz or external resonator) and the clock prescaler. I assume the firmware is compiled for an external quartz and 8MHz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 12, 2015, 02:56:45 pm
Thanks, I tried FW1.11M328 but it displays rubbish after the power on screen? Could this be because of incorrect fuse settings? Seems the Flash and eprom program fine.

Flashed a firmware with a language that your display does not support?
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 12, 2015, 03:34:58 pm
Thanks, I tried FW1.11M328 but it displays rubbish after the power on screen? Could this be because of incorrect fuse settings? Seems the Flash and eprom program fine.

Flashed a firmware with a language that your display does not support?

Possibly, I used the EN folder, but it does say testing... on the powerup screen. Now I've got to build an HV programmer to reset the fuses! puddles of fun.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 12, 2015, 04:11:16 pm
Why would you want to do that? Simply try flashing a different firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 12, 2015, 04:14:28 pm
Why would you want to do that? Simply try flashing a different firmware.

I've flashed pretty much any firmware I could find including the eeprom. Some power up with a bat & test screen but subsequent screens are garbage text. This is on a new ATMega328p, I didn't refresh the original with 1.05.

If anyone has an eep & hex combo (upload here) that works on a banggood board I'd be happy to try it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 12, 2015, 04:36:04 pm
I'd like to suggest two things. First, if you don't have much money to put into a decent AVR ISP programmer, just get the cheapest one from eBay. There is no need for HV to program fuses unless your chip refuses to be programmed via ISP, and it beats trying to get Arduino to do something that it doesn't like doing. Second, "garbage text" doesn't tell much. Images could help a bit in such cases.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 12, 2015, 05:48:04 pm
I'd like to suggest two things. First, if you don't have much money to put into a decent AVR ISP programmer, just get the cheapest one from eBay. There is no need for HV to program fuses unless your chip refuses to be programmed via ISP, and it beats trying to get Arduino to do something that it doesn't like doing. Second, "garbage text" doesn't tell much. Images could help a bit in such cases.

I'm a PIC programmer with PIC tools, if this was a PIC based project I'd have it working by now. I've even considered porting it!

Here's the rub, there are several modifications to the original design, crystal, LCD- GLCD display, voltage reference, HV zener, rotary encoder, Mega8, 168, 328... the list goes on. This makes it a little daunting to anyone unfamiliar with AVR programming. Worse yet are 99% of the programmers for ATMEL are the LV serial variety, so if you mess up the fuse settings well that's that. I've messed up a couple of 328p when trying to set the fuses. This command -U efuse:w:0xfc:m would set the lfuse to 0x04 go figure.

I think the Arduino is a nifty bit of kit, simple IDE to setup & install, cross platform, and a no brainer workflow. On the other hand I have no real interest or use for ATMEL micro controllers or wish to blow $85 CDn on an AVR Dragon for what will amount to a one off endeavour. I simply want to upgrade a banggood clone to 1.11k or possible 1.17m (is one better than the other?). I'm using a bit pirate as a programmer. I might pick up a USBTiny programmer as they're supposed to work with OS X.

Seems I'm not the only person that had problems upgrading the firmware on an MK168. Based on this thread alone looks like most folks don't get it working without some help.

I've tried the files in the UK & EN directories (EN english? UK english? err what) FW 1.11K latest from this site. http://www.avrtester.tode.cz/index.php?p=firmware (http://www.avrtester.tode.cz/index.php?p=firmware) But without knowing what options were chosen it makes it tough to know if it'll work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 12, 2015, 07:13:08 pm
Here's the rub, there are several modifications to the original design, crystal, LCD- GLCD display, voltage reference, HV zener, rotary encoder, Mega8, 168, 328... the list goes on. This makes it a little daunting to anyone unfamiliar with AVR programming.

Not sure I understand how one follows from the other. The software options need to match your hardware, but that's how it would have been with any microcontroller. So, you simply use, for example the st7565 firmware if you have an st7565-based screen. Pretty straightforward in most cases.

I simply want to upgrade a banggood clone to 1.11k or possible 1.17m (is one better than the other?).

They are a little different, but it's best to try both first-hand to see which one you like better.

Seems I'm not the only person that had problems upgrading the firmware on an MK168. Based on this thread alone looks like most folks don't get it working without some help.

Which I find very strange. They seem to be just a rather vanilla implementation of the circuit, so the firmware from mikrocontroller.net, whether m or k, should just work if the flash and EEPROM are programmed correctly. Hopefully, you're not flashing M168 firmware into your 328p?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 12, 2015, 09:10:15 pm
I've flashed pretty much any firmware I could find including the eeprom. Some power up with a bat & test screen but subsequent screens are garbage text. This is on a new ATMega328p, I didn't refresh the original with 1.05.

For a brand new ATmega you have to set the fuses, since the default setting is to use the internal RC as clock source and the 1:8 prescaler, resulting in an 1MHz MCU clock.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 12, 2015, 09:20:27 pm
I've flashed pretty much any firmware I could find including the eeprom. Some power up with a bat & test screen but subsequent screens are garbage text. This is on a new ATMega328p, I didn't refresh the original with 1.05.

For a brand new ATmega you have to set the fuses, since the default setting is to use the internal RC as clock source and the 1:8 prescaler, resulting in an 1MHz MCU clock.

Wouldn't the LCD work normally though?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 12, 2015, 09:35:04 pm
Yes. Just slower.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 12, 2015, 09:46:19 pm
What's the difference between the EN & UK versions? Spelling?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 12, 2015, 10:00:55 pm
EN is supposed to be English. UK... I have no clue. Ukrainian? I doubt that it stands for United Kingdom.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 12, 2015, 11:26:33 pm
Well I'll be, I was using the wrong UK firmware. 1.11K flashed no problem, thank you.

I'll still have to get the fuses working but that can wait, I'll flash the original chip tonight.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 13, 2015, 05:44:04 am
I've flashed pretty much any firmware I could find including the eeprom. Some power up with a bat & test screen but subsequent screens are garbage text. This is on a new ATMega328p, I didn't refresh the original with 1.05.

For a brand new ATmega you have to set the fuses, since the default setting is to use the internal RC as clock source and the 1:8 prescaler, resulting in an 1MHz MCU clock.

I got it working, it's an excellent bit of kit and I'm gobsmacked that you're the Markus that designed the thing :-+

My noob level AVR experience got me into trouble as I had to get the hang of avrdude plus a bus pirate pressed into service as a programmer and sort out which firmware worked with the banggook kit.

Did I mention it's a great addition to the handy as anything tool collection.
(http://www.electro-tech-online.com/imgcache/4956-JunebugMongoose.jpg)
FYI: a few years back I designed the Junebug kit, a PICkit2 programmer tutor, so I'm not completely...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 13, 2015, 11:19:10 am
I got it working, it's an excellent bit of kit and I'm gobsmacked that you're the Markus that designed the thing :-+

Great! And nope, I'm the Markus who does the m-firmware. The Markus who did the original design abandoned the project. Karl-Keinz (k-firmware) took over and I joined in.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jimmc on March 13, 2015, 01:40:56 pm
Glad you got it working, I had used 1.11k from http://www.mikrocontroller.net/svnbrowser/transistortester/#dirlist (http://www.mikrocontroller.net/svnbrowser/transistortester/#dirlist) but I couldn't find the revision I had used (360?).

I believe there is now a version 1.12k (latest is always under 'trunk') but I haven't tried it yet.

Jim
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on March 13, 2015, 02:10:06 pm
Nice going.
As far as my project I have given up on it  for the moment.
Just do not know much about AVR programming and got to see if I can find a better noob training video.
I do know I was not sending anything to my chip.  Read somewhere on this thread about the file size was too large. So that is most  likely my problem.
So think mine in blank and giving me just a bar when the test button is pressed.

Not sure if I even have the correct programmer
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 13, 2015, 04:39:53 pm
Nice going.
As far as my project I have given up on it  for the moment.
Just do not know much about AVR programming and got to see if I can find a better noob training video.
I do know I was not sending anything to my chip.  Read somewhere on this thread about the file size was too large. So that is most  likely my problem.
So think mine in blank and giving me just a bar when the test button is pressed.

Not sure if I even have the correct programmer

It looks like a USBTiny. If it's not a 328p get a 328p before you begin.
Assuming you're using an ATMega328p, from your command prompt try.
 avrdude -c usbtiny -p m328p
Title: Re: $20 LCR ESR Transistor checker project
Post by: jimmc on March 13, 2015, 07:31:23 pm
Nice going.
As far as my project I have given up on it  for the moment.
Just do not know much about AVR programming and got to see if I can find a better noob training video.
I do know I was not sending anything to my chip.  Read somewhere on this thread about the file size was too large. So that is most  likely my problem.
So think mine in blank and giving me just a bar when the test button is pressed.

Not sure if I even have the correct programmer

I'm an AVR newbie too, I found that AVRDudess (http://blog.zakkemble.co.uk/avrdudess-a-gui-for-avrdude/ (http://blog.zakkemble.co.uk/avrdudess-a-gui-for-avrdude/)) GUI for AVRDude made my life much easier.
I did have problems installing LibUSB until I used Zadig (http://zadig.akeo.ie/ (http://zadig.akeo.ie/)) which sorted the installation for me. (Windows 8.1)

Jim
Title: Re: $20 LCR ESR Transistor checker project
Post by: coromonadalix on March 13, 2015, 08:45:24 pm
With windows 8.1  for me    the usbtiny v3 dongle works best, it has the 6 and 10 pins connectors, avrdude and avrdudess are great.

Had many troubles with Atmel products ( i have avr dragon, isp mkII, stk500  etc ...)  passed windows 8,  the damned drivers signatures ....  are a pain.

Be careful,  flashing some mega 328 with no crystal  may give errors ... depending of the programmed fuses,    learned the hard way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 15, 2015, 05:29:41 pm
I got it working, it's an excellent bit of kit and I'm gobsmacked that you're the Markus that designed the thing :-+

Great! And nope, I'm the Markus who does the m-firmware. The Markus who did the original design abandoned the project. Karl-Keinz (k-firmware) took over and I joined in.

Do you have any documentation on your version of the firmware? Is it an enhanced K firmware or something alltogether different?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 16, 2015, 10:58:24 am
Great! And nope, I'm the Markus who does the m-firmware. The Markus who did the original design abandoned the project. Karl-Keinz (k-firmware) took over and I joined in.

Do you have any documentation on your version of the firmware? Is it an enhanced K firmware or something alltogether different?

The distribution package includes a readme file describing all the differences. The functionality of both firmwares is quite similar. but there are differences on how things are done. And the m-firmware lacks support of graphical LCDs (might change). The m-firmware measures caps down to 5pF for example, or is able to distinguish MT1 and MT2 of a detected TRIAC.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on March 16, 2015, 06:07:21 pm

And the m-firmware lacks support of graphical LCDs (might change). The m-firmware measures caps down to 5pF for example, or is able to distinguish MT1 and MT2 of a detected TRIAC.

Well, if you find yourself with a little time on your hands,  how about adding the graphics support (with pretty device pictures),   the ability to measure FET on resistance,  and a scope/logic analyzer mode?  I'd buy you a beer...
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 24, 2015, 06:53:23 pm
Great! And nope, I'm the Markus who does the m-firmware. The Markus who did the original design abandoned the project. Karl-Keinz (k-firmware) took over and I joined in.

Do you have any documentation on your version of the firmware? Is it an enhanced K firmware or something alltogether different?

The distribution package includes a readme file describing all the differences. The functionality of both firmwares is quite similar. but there are differences on how things are done. And the m-firmware lacks support of graphical LCDs (might change). The m-firmware measures caps down to 5pF for example, or is able to distinguish MT1 and MT2 of a detected TRIAC.

I'm going to give your firmware a try, mind posting a link to the distribution package? The sites I've found are all in German.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2015, 07:11:19 pm
I'm going to give your firmware a try, mind posting a link to the distribution package? The sites I've found are all in German.

You'll find the source at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/) or pre-compiled versions at http://www.avrtester.tode.cz/index.php?p=firmware (http://www.avrtester.tode.cz/index.php?p=firmware) for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BlueBill on March 26, 2015, 02:02:09 pm
I've tried 1.17m

It seems somewhat different, it seems to be in continuous auto test mode and it doesn't begin a calibrate when I connect all three leads on power up. Also I haven't found any other test modes (holding down the switch on the k firmware). Does it need the rotary switch?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 26, 2015, 05:29:41 pm
I've tried 1.17m

It seems somewhat different, it seems to be in continuous auto test mode and it doesn't begin a calibrate when I connect all three leads on power up. Also I haven't found any other test modes (holding down the switch on the k firmware). Does it need the rotary switch?

Please read the README file in the distribution archive. Everything is explained there. Power on the tester with a long key press (>0.3s) for the auto-hold mode. For the menu short circuit all three probes or press the test button two times (short key presses). And it doesn't require a rotary encoder, besides for the squarewave generator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sasa_mm on March 27, 2015, 12:23:24 am
Hello
I bought on ebay this esr meter
(http://lygte-info.dk/pic/ComponentTesters/Fish8840V2.1/DSC_7173.jpg)

everything is working ok except for the measurement of capacity and ESR
If I measuring small value capacitors <10uF readings are quite accurate but when I measure 100uF results are about 200uF (5 capatitors new and used) esr 0.20-0.40ohm
for 1000uF readings are 600-700uF,
470uF readings 0nF vloss around 1% esr no readings
1500, 2200uF readings 0nF

for all test I used brand new and used capatitators
Can someone help me to fix it? I try calibrate (connect pins 1 2 3 go trough test mode....)
thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on March 28, 2015, 12:19:16 pm
Most probably is the wrong setting of fuses. The correct values should be:
lfuse:0xff hfuse:0xd9 efuse:0x04

In the annex is backup original firmware of my tester (v2.1) and compiled firmware v1.12k revision 424 (Karl-Heinz Kübbeler).

Note
The problem could be a bad value C16. The correct value must be 1nF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sasa_mm on March 29, 2015, 03:18:52 pm
thanks for your response
I measured the c16 and its value is 1nF.
I'm new at this, to do new firmware I need USBASP interface?
like this
http://www.ebay.com/itm/USBASP-USBISP-AVR-Programmer-Adapter-10-Pin-Cable-USB-ATMEGA8-ATMEGA128-Arduino-/310506909410?pt=LH_DefaultDomain_0&hash=item484ba76ee2 (http://www.ebay.com/itm/USBASP-USBISP-AVR-Programmer-Adapter-10-Pin-Cable-USB-ATMEGA8-ATMEGA128-Arduino-/310506909410?pt=LH_DefaultDomain_0&hash=item484ba76ee2)
on ebay I can find that can flash ATmega328P or this one can?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on March 30, 2015, 08:05:19 am
Yes. I use exactly this type of USBasp programmers. In practice, you can use any ISP programmer intended for programming AVR MCU's.

The attached picture documents connection USBasp to board of my tester with the ISP connector.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Muxr on April 01, 2015, 03:13:38 pm
I got one of these for $15 off Ebay. So far it's been doing the right thing on any component I tried. I am actually kind of impressed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on April 01, 2015, 08:35:26 pm
How about a link to the seller's page.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Muxr on April 02, 2015, 04:52:37 am
How about a link to the seller's page.
here you go: http://www.ebay.com/itm/281476169022?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/281476169022?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on April 03, 2015, 11:37:53 am
Freshly compiled and tested version 1.12k revision 444 for Fish8840 Tester. To download at the end of the first post on the forum:
AVR Component Tester (RLC/ESR & Semiconductors Tester) (http://svetelektro.com/Forum/avr-component-tester-rlc-esr-semiconductors-tester-t30285.html)
or here  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on April 03, 2015, 03:51:40 pm
Which of the testers are that?, I found another one described here:
http://techobsessed.net/2015/01/fish8840-avr-transistor-tester-review/ (http://techobsessed.net/2015/01/fish8840-avr-transistor-tester-review/)

Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on April 03, 2015, 05:13:54 pm
My tester I bought here:
Ebay item: 281477820303 (http://www.ebay.com/itm/281477820303)

It is precisely this:
Review: Component Tester Fish8840 (http://lygte-info.dk/review/ComponentTester%20Fish8840%20UK.html)

Note:
These devices are sold by many vendors with different display panel. However, the motherboard is identical - see attached pictures.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on April 03, 2015, 05:42:55 pm
"Fish8840 Tester" version I preferred due to the easy implementation of other types of LCD (characters or graphics). Supplementing of few parts (LCD & ISP connector, trimer 10k) and changing one resistor on mainboard LCD (LED resistor) can be used classic 16x2 character LCD. Further adjustments can be with supplemented precision voltage source (R19, U3) and fix the connection of the voltage divider (R8, R15) for battery voltage measurement. A lot of useful information can be found in the official manual (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar) (by Karl-Heinz Kübbeler).
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on April 04, 2015, 09:03:49 am
My tester I bought here:
Ebay item: 281477820303 (http://www.ebay.com/itm/281477820303)

It is precisely this:
Review: Component Tester Fish8840 (http://lygte-info.dk/review/ComponentTester%20Fish8840%20UK.html)

Note:
These devices are sold by many vendors with different display panel. However, the motherboard is identical - see attached pictures.

I'm pretty sure all of those originated from Fish8840's TaoBao store.

The yellow "T-4" transistor tester Muxr linked to comes from 91Make's TaoBao, which is also the source of the inexpensive AD584 voltage reference boards, and the slightly more expensive plexi-encased versions that have been mentioned elsewhere on the forum before.

I like the presentation of the information on the 91Make version the best, but I like the "EZM Electronics Studio" GM328 (http://www.ebay.com/itm/GM328-transistor-tester-ESR-table-LCR-frequency-meter-square-wave-genera/171467739124) most because it is, as I understand it, closest to the original design, and open source firmware, plus the MCU is socketed and most of the components are through-hole for easier modification. There are variants with both a graphical display and a 2-line display.

I should probably finish the video I started editing comparing the three...but I probably won't.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on April 04, 2015, 01:46:10 pm
I've owned two of these testers now. The first was a Fish8840, which I stupidly killed with a (not very) charged capacitor. My current one is a "Yellow T-4", I got the up-market one with the plexiglass case, but the board looks identical to the cheap ones. I could never think of an easy way of casing the Fish8840 due to the separate display board needing either a stepped front panel or extending the ZIF socket and buttons.

A couple of observations. I agree that the Yellow "T-4" screen layout does seem to be the easiest to read (aging eyes) it also has an external 2.5V reference on board, even if it is only a TL431 rather than anything more exotic, I couldn't find one on the Fish8840 PCB. The battery voltage reading on the T-4 seems to start low on the "T-4" and slowly creep up over subsequent presses of the test button, no idea why that would be. The "T-4" has a slightly amusing representation of a Zener when connected between pins 1 and 3... It shows it as two opposite polarity diodes in SERIES rather than parallel.

The first thing I did after buying the second tester was to fit the relay input protection mod as detailed in the official manual. I hadn't realised just how sensitive the inputs would be to a capacitor that had been unsoldered and sitting for several days (charge recovery).
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on April 04, 2015, 03:31:56 pm
@Gyro:
I sent a personal message.
Title: Re: $20 LCR ESR Transistor checker project
Post by: intrax on April 11, 2015, 03:14:25 pm
What about this one:

http://m.ebay.com/itm/251791049879?nav=SEARCH (http://m.ebay.com/itm/251791049879?nav=SEARCH)

Power through rechargable batt. or usb and suitable for in circuit testing…

Any comments?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Towger on April 11, 2015, 03:52:21 pm
I am still waiting for the Free Electron version...
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on April 11, 2015, 03:58:29 pm
What about this one:
http://m.ebay.com/itm/251791049879?nav=SEARCH (http://m.ebay.com/itm/251791049879?nav=SEARCH)
Power through rechargable batt. or usb and suitable for in circuit testing…
Any comments?
All of this testers are just only different variations of the PCB - based on the standard wiring diagram (http://www.mikrocontroller.net/articles/Datei:TransistorTesterVC1.png) ;) This tester includes rechargeable battery - it is only one difference.  Images on ebay documented use of the original software by Karl-Heinz Kübbeler. In recent posts on the official discussion forum (http://www.mikrocontroller.net/topic/248078?page=7#4086662) you will find also some information.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yekuku on April 16, 2015, 11:16:13 pm
I got this one :  LCR-T5 Mega328 (http://www.banggood.com/LCR-T5-Mega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-p-945644.html) but I am having some issues...
(http://img.banggood.com/images/2014/xiemeijuan/09/SKU162928/SKU162928-1.jpg)
Unit seems to operate well but when testing electrolytic capacitors the screen flickers and gets upside down and mirrored.
Could it be a buggy factory firmware or a component issue? Did anybody else had the same problem?

Title: Re: $20 LCR ESR Transistor checker project
Post by: Richard Crowley on April 17, 2015, 04:57:47 am
Are you careful to fully discharge large capacitors before trying to test them?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yekuku on April 17, 2015, 09:06:54 am
Are you careful to fully discharge large capacitors before trying to test them?
Yes, all caps are properly discharged.
It looks to me like  a firmware / LCD screen compatibility issue. Any suggestions ?
The screen looks like this :
(http://i177.photobucket.com/albums/w211/yekuku/30f79999-6111-4a69-8e27-b3db3f8c31aa_zpswbwrajfm.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on April 18, 2015, 10:07:10 am
I'd suggest beefing up the supply decoupling as these boards seem to have minimal amounts, try a 10uF on the regulator output as a starting point and additional 100n's as close as you reasonably can to the chip.
Title: Re: $20 LCR ESR Transistor checker project
Post by: aRGee on April 18, 2015, 07:46:42 pm
Hi to all ! did anybody of you try to add a Rotary encoder to one of the chinese clones with a graphical display ? I tried a Rotary switch with my homemade tester with M-firmware and a 2*16 line display , it worked fine. When I tried the chinese clone with graphic display (the one from EZM electronics and discrete components) I didn't succeed, I tried a lot of combinations of PD1,PD2 and PD3 inputs of the atmega328.  Maybe somebody has an idea ?? Robert.

ps : I changed the 680R/470K resistors for the 0.1% types and also replaced the voltage regulator for a mcp1702-5002 and I got an accuracy of 0.1% back when measuring a precision resistor
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on April 19, 2015, 02:08:48 pm
Hello,
I bought this one on eBay. The software version is 1.11. I've got the documentation on the website of the developpers but I don't find what exactly are the information displayed for transistors: what are IC0 and ICs?
Thanks
Denis
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on April 20, 2015, 08:45:42 pm
Quote from: tom666
In the annex is backup original firmware of my tester (v2.1)
Thank you very mch! How did you get it?

What about this one:
http://m.ebay.com/itm/251791049879?nav=SEARCH (http://m.ebay.com/itm/251791049879?nav=SEARCH)
Any comments?
Feel free for a little look inside here:
http://www.mikrocontroller.net/topic/248078?page=7#4086662 (http://www.mikrocontroller.net/topic/248078?page=7#4086662)
FW from 15.04.2015:
http://www.mikrocontroller.net/topic/248078?page=7#4092967 (http://www.mikrocontroller.net/topic/248078?page=7#4092967)

Quote from: aRGee
When I tried the chinese clone with graphic display (the one from EZM electronics and discrete components) I didn't succeed, I tried a lot of combinations of PD1,PD2 and PD3 inputs of the atmega328.
I do not know EZM, only Fish and new LiIon, but the rotary must be activated in the makefile.
IMHO you need a special compiled version of your own, no standard-hex.
In some makefiles the rotary is pre activated.

Quote from: aRGee
I changed the 680R/470K resistors for the 0.1% types and also replaced the voltage regulator for a mcp1702-5002 and I got an accuracy of 0.1% back when measuring a precision resistor
.1% resistors are no bad idea but the LDO alone isn't the hack... you need to offer an external voltage reference.
My choose was a LT1009C, it's precision is 0.2%. So the overall prec should be better than 0.5%.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on April 21, 2015, 03:41:15 am
Hello,
I bought this one on eBay. The software version is 1.11. I've got the documentation on the website of the developpers but I don't find what exactly are the information displayed for transistors: what are IC0 and ICs?
Thanks
Denis

Vf forward
Vt threshold
S source
D drain
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on April 21, 2015, 05:44:59 am
Thanks Shock,
With BJT transistors the device indicates ICE0 and ICEs (forgot the ´E' in my previous post). Those values are most of the time 0.00mA with small signls transistors, and non zero for power transistors.  Probably collector-emitter currents, but in which conditions? There are also the current gain hFE and a voltage Uf (base-emitter).
For MOS and FET, the device indicates only two voltages: Vt and Uf and a capacity.
The user manual explains very well the measurement principles, but not the results.
Denis
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on April 21, 2015, 07:43:56 am
Gixy you can find all the acronyms with diagrams here
http://www.onsemi.com/pub_link/Collateral/AN1628-D.PDF (http://www.onsemi.com/pub_link/Collateral/AN1628-D.PDF)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on April 21, 2015, 09:54:30 am
Excellent document Shock, I appreciate.
ICEo (not ICE0) and ICEs are then leakage currents under reverse voltages. I found also this document from the device's developpers.
This device is really impressive!
Denis

Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on April 21, 2015, 10:42:08 am
Quote
.1% resistors are no bad idea but the LDO alone isn't the hack... you need to offer an external voltage reference.
My choose was a LT1009C, it's precision is 0.2%. So the overall prec should be better than 0.5%.

Having said that, it's worth just checking the accuracy of the cheapo TL431 reference on the board (if fitted) before swapping it - the one on mine reads a nice stable 2.501V  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Evil Lurker on April 23, 2015, 12:15:26 am
I'm debating on getting one of the Chinese "GM328 fish clone" testers.

Anyone know where I could land an unpopulated PCB so that I can use my own precision components?



Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on April 23, 2015, 04:54:05 am
Still be more economical to buy one and remove parts you dont want.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 23, 2015, 12:21:10 pm
Anyone know where I could land an unpopulated PCB so that I can use my own precision components?

There are several PCB layouts in the forum at http://www.mikrocontroller.net/topic/248078 (http://www.mikrocontroller.net/topic/248078) (mostly German) and from time to time someone organizes an aggregated order. But I haven't seen any shop selling bare PCBs yet. You can also find two PCBs in the firmware repo for DYI-ing (one is veroboard based, and the other one is for through-hole parts). There's also an rotary encoder / frequency counter adapter for character LCDs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mikronauts on April 25, 2015, 02:54:51 am
Hi - I just found this thread due to the Hackaday post.

Great little tool!

Wifey won't like it, but I think I'll build one this weekend. I don't have the requisite 0.1% 680R and 470K resistors, but I am certain I will find some relatively easily by measuring and sorting my 1% resistors.

I have all the other parts in my lab, and I ordered two 128x64 LCD's for later builds.

I downloaded the tarball, and I am now reading the v1.12k manual.

A big thank you to Markus and Karl-Heinz for your work on this.

Bill

---
http://Mikronauts.com (http://Mikronauts.com)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on April 25, 2015, 11:59:07 am
For owners of this tester which is offered on ebay under the designation as "LCR-T3" or "LCR-T4 Transistor Tester" I offer a way to update firmware. Devices have identical G-LCD (ST7565), but slightly different PCB. Update works on both versions of this tester. However, attention should be given to the fact that the ISP connector from the parts is mirrored. For this purpose I have pieced together a simple detachable :) adapter enabling the MCU to program without arranging the auxiliary ISP connector (see attached pictures). Many thanks to Roland Elmiger (hb9gaa) from the official discussion forum for providing the schematic diagram (http://www.mikrocontroller.net/topic/248078?page=6#3784106).
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on April 27, 2015, 05:06:19 am
I found this one GM328A firmware V1.12 with input port protection and 0.1% resistors. Menu has Transistor, Frequency, f-Generator,10-bit PWM, C=ESR@TP1:3, rotary encoder, Self Test, Contrast, Show Data, Switch Off           

U3 (V05) & D1 (KK 1450) may be similar to the protect circuit attached. Voltage regulators, 5V (AMS1117-5.0) & 3V3 (AMS1117-3.3) for LCD, U4 voltage reference TL431

http://www.ebay.com.au/itm/Latest-12864-LCD-Transistor-Tester-Capacitance-ESR-Meter-LCR-GM328A-Test-Clip-/321735790147?pt=LH_DefaultDomain_0&hash=item4ae8f28e43 (http://www.ebay.com.au/itm/Latest-12864-LCD-Transistor-Tester-Capacitance-ESR-Meter-LCR-GM328A-Test-Clip-/321735790147?pt=LH_DefaultDomain_0&hash=item4ae8f28e43)

http://www.ebay.com.au/itm/311343672563? (http://www.ebay.com.au/itm/311343672563?)

edit: added photo of component side of PCB.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on April 27, 2015, 07:45:49 am
Do these also have the function generator option in menu?
I found this one that advertise that feature, also claims to be V1.12. with input port protection and 0.1% resistors.
Can not find photo of component side of PCB.

bid ?

http://www.ebay.com.au/itm/Latest-12864-LCD-Transistor-Tester-Capacitance-ESR-Meter-LCR-GM328A-Test-Clip-/221755223038?pt=LH_DefaultDomain_0&hash=item33a1a42bfe (http://www.ebay.com.au/itm/Latest-12864-LCD-Transistor-Tester-Capacitance-ESR-Meter-LCR-GM328A-Test-Clip-/221755223038?pt=LH_DefaultDomain_0&hash=item33a1a42bfe)
[...]

For what it is worth, the function generator was enabled in the v1.11k firmware installed on the through-hole version from the same manufacturer early this year.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on April 27, 2015, 08:14:10 am
I thinking of getting the LCR-T3 above, can anyone confirm if has frequency generator too?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on April 27, 2015, 10:00:35 am
After updating the software (currently v1.12k) and extensions the hardware (see the official manual) will work:
- measurement of zener voltage above 4 Volt
- measure the voltage to 50V
- frequency generator
- frequency measurement
- 10-bit PWM
- using of a rotary pulse encoder with a push button for easier control of the menu function.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on April 27, 2015, 10:21:27 am
Thanks Tom666, I go ahead and get one, seem to be the best version, 6 pin ISP, external voltage reference, components all clearly marked with values, smd, compact design single pcb, no hardware faults (unlike fish). Latest firmware.

edit: After seeing component side of GM328, I bought the GM328 as it has protection and all same features above.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 27, 2015, 10:34:36 am
Since we're talking about the function generator (squarewave), would you be interested in a sinusodial signal too? I haven't looked into the details yet, but I think it would be possible with the help of an external low-pass filter (2 components) attached to the probe pins temporarily. I can't say anything about the frequency range yet, but it would be far less than the squarewave. BTW, what do you think about the squarewave generator (requires a rotary encoder) of the m-firmware? Is the user interface ok? Haven't got any feedback about that so far.
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on April 27, 2015, 11:30:30 am
I'd rather like to see a new reference design of the board that incorporates all features, e.g. encoder, zener and generator into it in a modular way.

I started to do such a design but due to time constraints didn't get any further than the attached schematic (which is missing the relay and diode input protection feature).

The sinusoidal wave gen would be okay to have, but I had no use-case so far.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on April 27, 2015, 11:52:08 am
Is this a true function generator capable of at the very minimum triangle or is this just square wave?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 27, 2015, 12:11:08 pm
Is this a true function generator capable of at the very minimum triangle or is this just square wave?

Just square wave.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on April 27, 2015, 01:24:19 pm
Thanks. Although unable to get latest versions working I am very happy with the original firmware and greatly appreciate the effort you put into this. But a little disappointed to see the term "function generator" used here which at the least would generally include triangle or sine.. This kind of stretching might be expected from Ebay chinese liars but IMO better to refer to it as "square wave generator" or "signal generator" to not get peoples hopes up. Anyway, thanks again for the wonderful design. It proved to be an invaluable tool here.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Richard Crowley on April 27, 2015, 01:41:04 pm
To be fair the use of the term "function generator" was introduced by a user, and none of the Ebay sellers appear to claim any sort of "function generator" feature.  The latest firmware revision appears to have frequency-controllable square wave generation, and @madires speculated about using an additional (external) low-pass filter to generate other wave shapes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on April 27, 2015, 02:23:03 pm
Yea, its unfortunate that bad terminology catches on so easily.

And it's true the Ebay sellers are more honest in their description of this particular product. What I was referring to was them calling NE555 boards and the like "function generators". Makes it very difficult to locate actual function generators which may not show up for many pages later. Also really aggravating when they call things like cheap OOK rx "super-heterodyne". Totally fraudulent and again makes it impossible to tell what is what.

BTW unlikely a square wave can be converted into anything useable with a filter. At least not over any useful range or circuit less complicated than an op amp or dds based generator. Speaking of which I think dedicating a few pins to general purpose SPI bus would make it very easy to implement a high performance AD9850 or AD9833 generator (12mhz!) for couple dollars with very few parts.

It would also be nice to add an LM311 for nanohenry and pf capability. Kinda like those Ebay cheapo testers that have extreme accuracy. Specially considering the comparator circuit is also very simple and costs pennies.



Title: Re: $20 LCR ESR Transistor checker project
Post by: Richard Crowley on April 27, 2015, 02:41:29 pm
But description "inflation" and misrepresentation is a time-honored tradition on Ebay.  It happens in all categories, not just electronics.  One must develop a high degree of "Ebay-fu" to find what you are really looking for, and filter out the "commercial puffery" and downright misinformation from the sellers.  And, of course many of the sellers having a tenuous grasp of the English language doesn't help, either.

And remember that just as there is the "$20 LCR/diode/transistor tester", there are similar products which actually ARE function generators.  For example...

"2014 Newest DDS Function Signal Generator Module Board Sine Square Sawtooth"
http://www.ebay.com/itm/2014-Newest-DDS-Function-Signal-Generator-Module-Board-Sine-Square-Sawtooth-/221636591065 (http://www.ebay.com/itm/2014-Newest-DDS-Function-Signal-Generator-Module-Board-Sine-Square-Sawtooth-/221636591065)

(http://i.ebayimg.com/00/s/NzIwWDk2MA==/z/rZkAAOSwkNZUjt4-/$_12.JPG)
And many others........
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 27, 2015, 02:49:28 pm
Thanks. Although unable to get latest versions working I am very happy with the original firmware and greatly appreciate the effort you put into this. But a little disappointed to see the term "function generator" used here which at the least would generally include triangle or sine.. This kind of stretching might be expected from Ebay chinese liars but IMO better to refer to it as "square wave generator" or "signal generator" to not get peoples hopes up. Anyway, thanks again for the wonderful design. It proved to be an invaluable tool here.

I was referencing another user, but I understand you. Just to make things clear, the k-firmware uses the term "Frequency Generator" and the m-firmware uses "Signal Generator". But I'll change it to "Square Wave Signal Generator" in the m-firmware to be absolutely clear.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 27, 2015, 02:53:54 pm
BTW unlikely a square wave can be converted into anything useable with a filter. At least not over any useful range or circuit less complicated than an op amp or dds based generator. Speaking of which I think dedicating a few pins to general purpose SPI bus would make it very easy to implement a high performance AD9850 or AD9833 generator (125mhz!) for couple dollars with very few parts.

No, the idea is to use some math plus PWM to create the signal. The purpose of the low-pass filter should be obvious by now ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on April 27, 2015, 03:14:41 pm
Oh yes, that makes much more sense. I was thrown off by Richards mention of "external filter". And IMO "Frequency Generator" and "Signal Generator" are perfectly accurate for square wave so no need to change that. I was just hoping we posters could avoid the "f" word (LOL) for square only.

And BTW in addition to the LC meter posted I do have one of those Atmega16 based function generators in Richards link. It's hard to believe you can actually buy those units fully assembled for 10 bucks or so. And can attest from experience they both perform even better than expected. Along with the semiconductor tester here it's hard to believe anything else would be needed by the average hobbyist or even most professionals. Modern marvels, specially considering what these things cost!

I will however continue to pine away for all these in one compact hand held unit. Maybe DMM type case. I know this can be done because a lot of the circuitry is common all 3 devices and source is available for many different platforms.  Maybe one day (or year) I will roll up my sleeves and give it a try.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pmsr on April 27, 2015, 08:36:17 pm
Does anyone know if the LCR-T5 version on Ebay is the same as the LCR-T4, just with a case? Are there other differences? Thinking of ordering this one and having a go at Tom666's v1.12k r453 EN firmware on it.

/Pedro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on April 28, 2015, 01:09:23 pm
No it's certainly a different PCB as it has the Lipo charger circuit and boost regulator on the back - there's a photo of the PCB somewhere. It looks as if the LCD aspect ratio is different too, which would be a s/w compatibility issue if so.

The T4 in a case is this one (not sure if there are any others):

http://www.ebay.co.uk/itm/Pocketable-12864-Transistor-Tester-Capacitance-ESR-Diode-Triode-Triac-MOS-Meter-/261548717202?pt=LH_DefaultDomain_3&hash=item3ce584b492 (http://www.ebay.co.uk/itm/Pocketable-12864-Transistor-Tester-Capacitance-ESR-Diode-Triode-Triac-MOS-Meter-/261548717202?pt=LH_DefaultDomain_3&hash=item3ce584b492)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on April 28, 2015, 07:07:05 pm
Gixy you can find all the acronyms with diagrams here
http://www.onsemi.com/pub_link/Collateral/AN1628-D.PDF (http://www.onsemi.com/pub_link/Collateral/AN1628-D.PDF)
+1 for the article. :-+ Thx!
Title: Re: $20 LCR ESR Transistor checker project
Post by: pmsr on April 29, 2015, 05:36:16 pm
The T4 in a case is this one (not sure if there are any others):

http://www.ebay.co.uk/itm/Pocketable-12864-Transistor-Tester-Capacitance-ESR-Diode-Triode-Triac-MOS-Meter-/261548717202?pt=LH_DefaultDomain_3&hash=item3ce584b492 (http://www.ebay.co.uk/itm/Pocketable-12864-Transistor-Tester-Capacitance-ESR-Diode-Triode-Triac-MOS-Meter-/261548717202?pt=LH_DefaultDomain_3&hash=item3ce584b492)

Thanks, Gyro. I can see now it is the same as the one on 91make.taobao.com, right down to the "multifuction" spelling error. Ordering it and will post pictures when I receive it.

/Pedro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on April 30, 2015, 11:56:09 am
@pmsr  You're welcome it seems you can tell a lot from the spellings  :) for instance the Fish888 based ones have "unknow component".

@Tom666  Many thanks for posting the V1.12k software for the T4. Any chance that you have a backup of the original T4 V2.07 in case I need to go back for the easier (read LARGE  :'( ) graphics?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on April 30, 2015, 01:09:47 pm
@Tom666  Many thanks for posting the V1.12k software for the T4. Any chance that you have a backup of the original T4 V2.07 in case I need to go back for the easier (read LARGE  :'( ) graphics?
I like to help :) A backup of the original firmware found in the posts by "samnmax" (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg612663/#msg612663).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on April 30, 2015, 02:23:38 pm
Great, thanks, I missed that one.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on May 02, 2015, 11:13:24 pm
hello, a bit offtopic, anybody have the lcr-t4 with plastic case?, can share the parts and measures of the plastic case needed for replicate it? i have no see the case alone for sale on the net.

thank you in advance.

best regards.

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on May 03, 2015, 08:56:29 am
Although it is not a Chinese box for LCR-T4, but can serve as inspiration :)
- Case for LCR-T4 Component Tester (http://www.thingiverse.com/thing:797733)
- Case for LCR-T4 Component Tester (http://www.thingiverse.com/thing:562715)
- Case for LCR-T3 Component Tester (http://www.thingiverse.com/thing:694790)
&
- Others (http://www.thingiverse.com/search?q=Transistor+Tester&sa=)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on May 03, 2015, 12:55:13 pm
Wow, nice case design! - 3d printed I assume  :o

Yes, I took the easy route of buying a T4 in the plastic (plexiglass?) case. I don't think I'd try to replicate it as it's all held together with tabs and slots - quite a precision job, even the display window is flush fitted with no visible glue line. No machining marks visible. Also the side panels taper with bottom thinner than the top. Top, bottom and T4 pcb are held by threaded brass spacers, again close tolerance. Not sure how much the tooling would have cost considering so few listings on ebay.

Anyway, photo attached. You can just see the small input protection relay below the zif socket (Needs 'the battery at bottom variant' to allow space - 2 types are listed on ebay). I have also added a small Off button top left of the yellow one to turn off immediately without waiting for the timeout - useful in 1-3 C/esr and R/L continuous measuring modes.

@tom666 As you can see, new 1.12k s/w loaded, nice bold text and added functions. No need to worry about the old backup now.  ;D Thanks

(http://)
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on May 03, 2015, 04:41:35 pm
Thank you very much for the very interesting responses :)

Best regards.

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on May 04, 2015, 07:07:29 am
Wow, nice case design! - 3d printed I assume  :o

Yes, I took the easy route of buying a T4 in the plastic (plexiglass?) case. I don't think I'd try to replicate it as it's all held together with tabs and slots - quite a precision job, even the display window is flush fitted with no visible glue line. No machining marks visible. Also the side panels taper with bottom thinner than the top. Top, bottom and T4 pcb are held by threaded brass spacers, again close tolerance. Not sure how much the tooling would have cost considering so few listings on ebay.

Looks like it may be a case from "100MHz (http://100mhz.taobao.com)." They seem to specialize in those tabbed acrylic cases.
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 07, 2015, 01:06:44 pm
I have some confusion about what is the best model of this component tester to buy among all.Which is you advice?Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on May 07, 2015, 06:08:31 pm
I have some confusion about what is the best model of this component tester to buy among all.Which is you advice?Thanks.
"Best" is relative to your requirements, as best as you can articulate them.

A few questions:

My favorite is the GM328 from EZM electronics studios because: It seems to use recent versions of the mainline firmware with minimal modifications, and good through-hole components, so it is ready to use without modification. On the other hand it has a socketed MCU, allowing you to try different firmwares easily, and through-hole components make it easier to modify if you so desire.  The main downside is that the configuration is a little awkward for putting in a case and the pads for testing SMD devices don't accommodate a lot of different orientations.

My next favorite is probably the versions from 91Make (T-4, etc). In their favor is that their custom firmware version makes the better use of graphical displays than the mainline firmware, and other proprietary forks. It also doesn't suffer from the battery-wasting power supply design of the Fish8840 variants. The single board should be easier to mount in an enclosure, and, people have managed to reprogram it without much trouble, but this comes at the expense of the nice UI design of the original firmware. The SMD pads also allow for more flexibility in component positioning than the GM328 (but not as much as the Fish8840). The main downside for use as-is is that the firmware doesn't have the mainline firmware's full set of features enabled.

Other people probably have their own take, and we may be able to give a better recommendation if you can clarify your requirements a bit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 07, 2015, 06:37:04 pm


A few questions:
  • Are you willing to tinker with the device at all?

Sure, I'm a geek... :)

 
Quote
  • If yes, how much? Once to install a recent version of the firmware, or on an ongoing basis?


I want to experiment different versions

Quote
  • Do you want it to come wrapped in a case, with test leads, etc?

I can add case later  as well test leads

Quote
  • How important is testing surface mount components?

Not really, I can always use my tweezer.
 

Quote
My favorite is the GM328 from EZM electronics studios because: It seems to use recent versions of the mainline firmware with minimal modifications, and good through-hole components, so it is ready to use without modification. On the other hand it has a socketed MCU, allowing you to try different firmwares easily, and through-hole components make it easier to modify if you so desire.  The main downside is that the configuration is a little awkward for putting in a case and the pads for testing SMD devices don't accommodate a lot of different orientations.

Yes, a PCB with though-hole component would be fine even if I could program the MCU in-circuit.Do you mean this?

eBay auction: #251653350287

Quote
My next favorite is probably the versions from 91Make (T-4, etc). In their favor is that their custom firmware version makes the better use of graphical displays than the mainline firmware, and other proprietary forks. It also doesn't suffer from the battery-wasting power supply design of the Fish8840 variants. The single board should be easier to mount in an enclosure, and, people have managed to reprogram it without much trouble, but this comes at the expense of the nice UI design of the original firmware. The SMD pads also allow for more flexibility in component positioning than the GM328 (but not as much as the Fish8840). The main downside for use as-is is that the firmware doesn't have the mainline firmware's full set of features enabled.

Could you post link of both, please?
Anyway some years ago I bought this version, it came with firmware 1.05k onboard.It works quite well but it as some nasty bugs, for example ESR measurements are totally wrong compared to the right ones of my Bob Parker Blue tester.I see on Markus F. repository that newer firmwares have been released.So, it would be possible to upgrade it and , if yes, to which version?[/list]
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on May 07, 2015, 09:34:56 pm
Quote
My favorite is the GM328 from EZM electronics studios because: It seems to use recent versions of the mainline firmware with minimal modifications, and good through-hole components, so it is ready to use without modification. On the other hand it has a socketed MCU, allowing you to try different firmwares easily, and through-hole components make it easier to modify if you so desire.  The main downside is that the configuration is a little awkward for putting in a case and the pads for testing SMD devices don't accommodate a lot of different orientations.

Yes, a PCB with though-hole component would be fine even if I could program the MCU in-circuit.Do you mean this?

eBay auction: #251653350287
Yeah, that's the one.

Quote
My next favorite is probably the versions from 91Make (T-4, etc). In their favor is that their custom firmware version makes the better use of graphical displays than the mainline firmware, and other proprietary forks. It also doesn't suffer from the battery-wasting power supply design of the Fish8840 variants. The single board should be easier to mount in an enclosure, and, people have managed to reprogram it without much trouble, but this comes at the expense of the nice UI design of the original firmware. The SMD pads also allow for more flexibility in component positioning than the GM328 (but not as much as the Fish8840). The main downside for use as-is is that the firmware doesn't have the mainline firmware's full set of features enabled.

Could you post link of both, please?
[/quote]
Kind of a hassle for me to find links right now on my mobile. I think other people have described and linked to both of these in the last few pages.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on May 08, 2015, 10:01:40 am
Quote from: caius
Quote from: eas
My next favorite is probably the versions from 91Make (T-4, etc). ...
Could you post link of both, please? ...
for example:
Update firmware for LCR-T3 & LCR-T4 Tester by 91make (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867)
Correction to my original post:
G-LCD are identical but PCBs have slightly different dimensions.


eBay auction: #371301439496 - LCR-T3 Tester by 91make
eBay auction: #311331001449 - LCR-T4 Tester by 91make

Quote from: caius
Anyway some years ago I bought this version, it came with firmware 1.05k onboard. It works quite well but it as some nasty bugs, for example ESR measurements are totally wrong compared to the right ones of my Bob Parker Blue tester. I see on Markus F. repository that newer firmwares have been released.So, it would be possible to upgrade it and , if yes, to which version?
I recommend to update the firmware through the ISP connector. Setting the fuses for M168 you have in the attached image. File contains firmware (final v1.09k for M168) will work without recommended hardware changes (see the official manual). Is set so as not by trouble with the message "CELL".
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 08, 2015, 12:06:56 pm

for example:
Update firmware for LCR-T3 & LCR-T4 Tester by 91make (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867)
Correction to my original post:
G-LCD are identical but PCBs have slightly different dimensions.


eBay auction: #371301439496 - LCR-T3 Tester by 91make
eBay auction: #311331001449 - LCR-T4 Tester by 91make

Thanks you Tom for your explanations.So, at the end your advice is to get an LCR-T3 or LCR-T4 instead of the GM328 with though-hole components?

Quote
I recommend to update the firmware through the ISP connector. Setting the fuses for M168 you have in the attached image. File contains firmware (final v1.09k for M168) will work without recommended hardware changes (see the official manual). Is set so as not by trouble with the message "CELL".

OK, I will upgrade it to v1.09k.Regarding the hardware changes, I guess you refer to the ones mentioned in this manual:

http://radioskot.ru/_fr/6/ttester_eng105k.pdf (http://radioskot.ru/_fr/6/ttester_eng105k.pdf)

I'll figure out if my PCB need these changes by comparing its layout with the one showed in the manual.

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 08, 2015, 01:40:58 pm
Quote from: caius
So, at the end your advice is to get an LCR-T3 or LCR-T4 instead of the GM328 with though-hole components?
It is difficult to decide - it's all a matter of taste :) In the case of damage MCU I think will be easier maintainable GM328 - but it has a slightly larger PCB size. The advantage GM328 is also the possibility of using classical character LCD.]

OK, I will think about and decide.

 
Quote
You do not need to make any correction of hardware. Use only firmware which I uploaded here ;)

I'm just trying it.Since I'm using a TL866CS programmer, the  configuration of efuse is a bit different, I can change only three bits.Is 0xF9 the same of 0x01?
I could use my Arduino Mega2550 and AVRdude to program the ATmega168 but I'm bit lazy now :)
Besides, I can't see how to program the EEPROM of the MCU with my TL866CS.
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on May 08, 2015, 01:51:26 pm
Extended fuse F9 = 01 :) because some numerical values containing undefined bits.
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 08, 2015, 02:25:10 pm
Quote from: caius
I can't see how to program the EEPROM of the MCU with my TL866CS.
Code memory = TransistorTester.hex
Data memory = TransistorTester.eep
Config = Fuses

OK, thanks.
A question : if ATMEGA168 EEPROM size is 512 bytes, how could I program 2KB of data of the .EPP file?
Anyway my programmer doesn't recognize MCU, I double-checked ICSP diagram and it's right.There are two GND points on tester ICSP header but I connected only one to the programmer, I don't think it's due this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on May 08, 2015, 02:37:08 pm
File contents is in hex format (http://en.wikipedia.org/wiki/Intel_HEX).
Just plug only one GND. Check the presence Vcc (5V)while programming.
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 08, 2015, 03:00:38 pm
File contents is in hex format (http://en.wikipedia.org/wiki/Intel_HEX).
Just plug only one GND. Check the presence Vcc (5V)while programming.

I have not yet tried to program it since programmer doesn't recognize ATmega168 even reading it (ID error).There is something wrong for sure, I suspect the programmer itself, I'm powering the MCU through it (it can deliver up to 120mA on the ICSP VCC pin).Part name on chip is scratched off but it shoud be a ATmega168.
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 08, 2015, 07:04:08 pm
OK, I succesfully programmed the ATmega168 on my transistor tester with Arduino as ISP and AVRdude, all went fine.
I noticed that the 1.09k firmware adds some new features like reverse leakage current (ir) measurements and Vloss measurement, are these reliable?
Besides,it seems that with this firmware valid test points for capacitors are only TP1 and TP3.If you use TP1 and TP2 you get "no unknown or damaged part" message, if you use TP2 and TP3 you get wrong measurements.Do you confirm this?
Thanks again for you help.

P.S.
With this firmware ESR measurement is more accurate but there is always a difference of .7 Ohms compared to my Bob Parker ESR meter.
Is there anything  I can do on the hardware to improve it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on May 09, 2015, 07:19:05 am
I think it will be a problem with the connection TP2 on the MCU port.
Check that the value of R2 to R7 are correctly (680, 470k) and their connection to the TP1 to TP3 (mainly TP2).
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 09, 2015, 08:50:46 am
I think it will be a problem with the connection TP2 on the MCU port.
Check that the value of R2 to R7 are correctly (680, 470k) and their connection to the TP1 to TP3 (mainly TP2).

I check connection and resistors values and they are OK.I think it's something releted to this 1.09K firmware or I really need to modify hardware.I look at this manual:

http://radioskot.ru/_fr/6/ttester_eng105k.pdf (http://radioskot.ru/_fr/6/ttester_eng105k.pdf)

Can the hardware changes be made also on my PCB revision or are they already inplemented?Layout is quite different as well as silkscreening of components.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on May 09, 2015, 11:48:32 am
Correction of the Chinese version testers (Booster edition 2.x) you will find since version 1.06k of user guide (attached pdf file contained a specific section of this manual).

The only one difference is that your version does not contain 8MHz crystal. Then it should be added blocking capacitor 100nF directly to the MCU pins. Other error is (this does not affect the functionality) the use of zener diode D1 instead of a source of precision 2.5V reference voltage. If you would like to use the new features it is appropriate to replace the MCU for ATmega328.

Despite these minor deficiencies, I think the tester should work after upgrade firmware without hardware modifications.
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 09, 2015, 03:02:46 pm
The only one difference is that your version does not contain 8MHz crystal. Then it should be added blocking capacitor 100nF directly to the MCU pins. Other error is (this does not affect the functionality) the use of zener diode D1 instead of a source of precision 2.5V reference voltage. If you would like to use the new features it is appropriate to replace the MCU for ATmega328.

Ok, I'll try an ATmega328.I presume that with this more capable MCU I can try latest firmware, which one in particular?.Are the fuses values the same you suggested me for 1.09k upgrade??
Anyway I could measure (out-of-circuit) on my revision Booster Edition 2.3 PCB two 160nF capacitors instead of 100nF ones silkscreened on Booster 2.2.I will replace these with correct values as well as put a 100nF by-pass capacitor across VCC and GND of MCU and replace diode D1 with a precise shunt voltage reference.

P.S.
A quick question:
Are the GM328 and T3/t4 component testers based on same schematics of mine?
Thank you again for you help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on May 09, 2015, 05:03:59 pm
For MCU M328 you can use the latest version of the software. For example, the final v1.11k or development version 1.12k (author Karl-Heinz Kübbeler). You can also use the alternative version of the software by Markus Reschke (current v1.17m).

Everything is available in the SVN repository:
https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)

Setting fuses for M328 (applies to all versions of software):
RC operation, CLK 8MHz
lfuse:0xe2 hfuse:0xd9 efuse:0xfc (0x04)

8MHz crystal - full swing crystal
lfuse:0xf7 hfuse:0xd9 efuse:0xfc (0x04)

8MHz crystal - low power
lfuse:0xff hfuse:0xd9 efuse:0xfc (0x04)

"GM328" is identical with standard schematics diagram, but the "T4" have different mapping of MCU ports with the G-LCD - connection as "strip grid board" (using of MCU ports PD1 to PD4).

Clone of GM328 (by Dietrich L.):
https://www.mikrocontroller.net/topic/345717#3856301 (https://www.mikrocontroller.net/topic/345717#3856301)

Schematics diagram of LCR-T3 & LCR-T4 (by Roland Elmiger):
https://www.mikrocontroller.net/topic/248078?page=6#3784106 (https://www.mikrocontroller.net/topic/248078?page=6#3784106)
Title: Re: $20 LCR ESR Transistor checker project
Post by: kubi48 on May 09, 2015, 05:23:36 pm
The version 1.11k and also the developer version 1.12k can also be used with a mega168. Of course not all features like support of graphical display or the menu functions are available for the mega168. For 1.11k and 1.12k version shorter current pulses are used for the ESR measurement. So the ESR can be measured for lower capacity values like 100nF. The ESR result  of the TransistorTester match to a 10kHz measurment, not to a 100kHz result, which is often used. If you try to compile the source for a mega168 target, you should use a new avr-gcc revision like 4.8.2 , because the code optimizing of newer versions is better. Otherwise the code may not match to the 16k flash memory.
If you wish to use the full selftest with a mega168, you must deselect one of two hFE measurement approches first (NO_COMMON_COLLECTOR_HFE or NO_COMMON_EMITTER_HFE).
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 09, 2015, 07:31:21 pm
The version 1.11k and also the developer version 1.12k can also be used with a mega168. Of course not all features like support of graphical display or the menu functions are available for the mega168. For 1.11k and 1.12k version shorter current pulses are used for the ESR measurement. So the ESR can be measured for lower capacity values like 100nF. The ESR result  of the TransistorTester match to a 10kHz measurment, not to a 100kHz result, which is often used. If you try to compile the source for a mega168 target, you should use a new avr-gcc revision like 4.8.2 , because the code optimizing of newer versions is better. Otherwise the code may not match to the 16k flash memory

OK, thanks for explanation

Quote

If you wish to use the full selftest with a mega168, you must deselect one of two hFE measurement approches first (NO_COMMON_COLLECTOR_HFE or NO_COMMON_EMITTER_HFE).

I just noticed that self-test in not implemented in V1.09K like in the old V1.05K
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 09, 2015, 09:35:13 pm
For MCU M328 you can use the latest version of the software. For example, the final v1.11k or development version 1.12k (author Karl-Heinz Kübbeler). You can also use the alternative version of the software by Markus Reschke (current v1.17m).

Everything is available in the SVN repository:
https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)

Setting fuses for M328 (applies to all versions of software):
RC operation, CLK 8MHz
lfuse:0xe2 hfuse:0xd9 efuse:0xfc (0x04)

8MHz crystal - full swing crystal
lfuse:0xf7 hfuse:0xd9 efuse:0xfc (0x04)

8MHz crystal - low power
lfuse:0xff hfuse:0xd9 efuse:0xfc (0x04)

"GM328" is identical with standard schematics diagram, but the "T4" have different mapping of MCU ports with the G-LCD - connection as "strip grid board" (using of MCU ports PD1 to PD4).

Clone of GM328 (by Dietrich L.):
https://www.mikrocontroller.net/topic/345717#3856301 (https://www.mikrocontroller.net/topic/345717#3856301)

Schematics diagram of LCR-T3 & LCR-T4 (by Roland Elmiger):
https://www.mikrocontroller.net/topic/248078?page=6#3784106 (https://www.mikrocontroller.net/topic/248078?page=6#3784106)

Thank you for your exhustive explanation, I can say you are a real expert of these component testers  :)
According you, which could be the next step of hardware/software development?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on May 09, 2015, 10:59:11 pm
Mainly many thanks to deserve Mr. Markus Frejek, Mr. Karl-Heinz Kübbeler (kubi48) and Mr. Markus Reschke (madires).
I only collect the information available on the Internet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: zomi on May 10, 2015, 05:24:36 pm
Tom, have one of the fish8840 and trying to change the lcd..
Broke the original one ..

Added the trimmer..
and changed the resistor..
But I just get a display full of blocks..

Do I need to reprogram it to work properly ?


try the mod you showed here.

https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg644091/#msg644091
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on May 11, 2015, 07:28:38 am
Quote from: zomi
... have one of the fish8840 and trying to change the lcd..
Added the trimmer..
and changed the resistor..
But I just get a display full of blocks..
Do I need to reprogram it to work properly?

Yes, you need to use firmware designed for character 2x16 LCD:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/)
Fuses:
lfuse:0xf7 hfuse:0xd9 efuse:0xfc (0x04)

Note:
For battery voltage measurement (divider R8, R15) you can modify in Makefile this settings to:
CFLAGS += -DBAT_NUMERATOR=66
CFLAGS += -DBAT_DENOMINATOR=33
In principle, however, you can use the firmware from that folder without editing Makefile - value of Vbat will not be OK.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Anks on May 14, 2015, 07:17:45 am
Could anyone clarify if this tester can do ESR in circuit and if there are any modifications or specific firmware that has to be made/used.

The specific tester in question is this http://www.ebay.co.uk/itm/Mega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-LCR-T3-/121595483585?pt=LH_DefaultDomain_3&hash=item1c4fa7d5c1 (http://www.ebay.co.uk/itm/Mega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-LCR-T3-/121595483585?pt=LH_DefaultDomain_3&hash=item1c4fa7d5c1)

Any help much appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on May 14, 2015, 08:55:14 am
It is necessary to make a firmware upgrade:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867)
or
https://www.mikrocontroller.net/topic/248078?goto=4120737#4105488 (https://www.mikrocontroller.net/topic/248078?goto=4120737#4105488)

Use the actual version from the SVN archive designed for this type of tester (LCR-T3):
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/)
Fuses:
lfuse:0xf7 hfuse:0xd9 efuse:0xfc (0x04)

I recommend to read the manual:
https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: nassosxlvbros on May 15, 2015, 07:42:59 am
Hi to all from Athens!
After reading a lot for this tester I decide to get one!  :)
So I bought this tester,4 days ago,plug in a 9V battery and worked fine....Suddently after a dozen of measures refuses to power on (only the green LCD light goes on when I press  test button)...I left it,check battery,connections,bad solderings etc,but all seems OK.,then I put it away....Next day worked well for some time, but after  4-5 measurements stops again....
What is going on ???
Title: Re: $20 LCR ESR Transistor checker project
Post by: nassosxlvbros on May 15, 2015, 07:52:01 am
coil measurement....and after that,tester is dead.... :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on May 15, 2015, 08:10:10 am
I found this one GM328A firmware V1.12 with input port protection and 0.1% resistors. Menu has Transistor, Frequency, f-Generator,10-bit PWM, C=ESR@TP1:3, rotary encoder, Self Test, Contrast, Show Data, Switch Off           

U3 (V05) & D1 (KK 1450) may be similar to the protect circuit attached. Voltage regulators, 5V (AMS1117-5.0) & 3V3 (AMS1117-3.3) for LCD, U4 voltage reference TL431

got my tester today and have updated my original post with more details above. Its Hardware PCB ver 1.11

One thing i have noticed is the red LED seems a bit point less, it always on and only goes off when button is pressed. Is there any other purpose for it?
Think I may just remove it if it has no other use, Back light is bright enough to let me know its on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on May 15, 2015, 09:16:43 am
Unfortunately the Red LED is part of the power switching circuit - it's in the collector circuit of T1 which holds the power on once the button is released. Check the schematic in the official AVR ttester manual.

If you simply remove the LED then the tester will turn off as soon as you release the button. Shorting it should work, but the current path is still there.

The T3 and T4 testers have been a bit more economical by connecting the LCD backlight LED in this circuit position (though I think they've lowered R7 a bit to give it more current) instead of simply powering it off the 5V rail.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on May 15, 2015, 09:41:31 am
Thanks for the info, I checked the circuit, My R7 is 2k2  and circuit recommends 3k3 so that should help reduce current and dim the LED. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on May 15, 2015, 09:54:16 am
Next day worked well for some time, but after  4-5 measurements stops again.... What is going on ???

Did you discharge that big cap before testing again? Although it hasn't happened with me this is said to damage the unit. Another reason to avoid the slick but more expensive units with soldered in MCU. Socket versions are getting hard to find now but ordered with a few spare Mega328 chips can be a life saver.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nassosxlvbros on May 15, 2015, 10:38:39 am
Next day worked well for some time, but after  4-5 measurements stops again.... What is going on ???

Did you discharge that big cap before testing again? Although it hasn't happened with me this is said to damage the unit. Another reason to avoid the slick but more expensive units with soldered in MCU. Socket versions are getting hard to find now but ordered with a few spare Mega328 chips can be a life saver.

Of course I discharge every cap before measure.Tester does this even when I test resistors.....any ideas?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2015, 12:59:06 pm
Hi to all from Athens!
After reading a lot for this tester I decide to get one!  :)
So I bought this tester,4 days ago,plug in a 9V battery and worked fine....Suddently after a dozen of measures refuses to power on (only the green LCD light goes on when I press  test button)...I left it,check battery,connections,bad solderings etc,but all seems OK.,then I put it away....Next day worked well for some time, but after  4-5 measurements stops again....
What is going on ???

When powering on, does the display show the battery status briefly?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on May 15, 2015, 01:00:01 pm
Only a couple of things I can think of-

1. Beef up the supply decoupling after (and possibly before) the 5V regulator, add a 10uF if there isn't one already. Inductors and high value capacitors might put additional strain on the 5V rail regulation.

2. Check the pullup on the reset pin and associated track to the programming header footprint.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on May 15, 2015, 02:03:24 pm
what's your battery voltage with backlight on ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: nassosxlvbros on May 15, 2015, 02:08:44 pm
Quote
When powering on, does the display show the battery status briefly?

When I push the test button (and tester works) yes,it shows first the battery voltage at 9-9,1 Volts...when trying to light up (no working mode hehehe...)only the green backlight of the display lights up and the upper line shows the 16 black (er,greyish) squares.... |O

Quote
what's your battery voltage with backlight on ?

9 Volts are always there.... either with a battery or from regulated power supply.Working or not,voltage is rock steady at 9volts...
Title: Re: $20 LCR ESR Transistor checker project
Post by: opty on May 15, 2015, 02:13:08 pm
... Another reason to avoid the slick but more expensive units with soldered in MCU. Socket versions are getting hard to find now but ordered with a few spare Mega328 chips can be a life saver.

I totally agree.

It's a pity there doesn't seem to be version that is both with socket and ISP header..

Opty
Title: Re: $20 LCR ESR Transistor checker project
Post by: paulie on May 15, 2015, 02:23:24 pm
Bahhh.. It only takes 10 seconds to solder a row of single header pins to bottom of the board. Fortunately, except for reset, they all ISP pins are nicely grouped together there. My biggest complaint is putting the contrast adjust where it's impossible to access with display installed. A simple hole under the trimmer or using rt angle version would have avoided that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2015, 09:22:12 pm
When I push the test button (and tester works) yes,it shows first the battery voltage at 9-9,1 Volts...when trying to light up (no working mode hehehe...)only the green backlight of the display lights up and the upper line shows the 16 black (er,greyish) squares.... |O

Looks like a bad solder joint.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on May 15, 2015, 09:37:19 pm
Black Squares on LCD is micro not working.  It not sending data  to LCD. Do you have 5V on regulator and micro ? You could check if crystal is oscillating, but they very reliable and most likely you have zapped your micro.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nassosxlvbros on May 15, 2015, 11:10:58 pm
I check everything lot of times,5volts are there (pins 7,20 ) when I press the button,stops when I release...Some times is working Ok some times not. Board is checked for everything wrong under the microscope,all solderings,joints,etc are perfect,all parts are OK,double and triple checked...

when it refuses to power on shows this pic:

Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on May 16, 2015, 12:06:26 am
I check everything lot of times,5volts are there (pins 7,20 ) when I press the button,stops when I release...Some times is working Ok some times not. Board is checked for everything wrong under the microscope,all solderings,joints,etc are perfect,all parts are OK,double and triple checked...

Were you always testing properly discharged capacitors? Make sure the button isn't bouncing perhaps capture it on the scope. Swap the battery.

Send it back if you can but if you can't, I'd resolder everything, then try soldering the test points directly to the component. In this case a resistor is probably the most simple test. Check the display connections as well. Then it's likely to be a faulty micro, design or software issue possibly caused by timing. But it's cheaper/faster to either get another one to rule out its inherent and then to perform a comparative test with duplicate components.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nassosxlvbros on May 16, 2015, 12:17:33 am
Battery is fresh always,my power supply noise free also.Caps are discharged every single time....The only thing that remains is the microcontroller...faulty chip or something else... :-// I already order another tester because is a much cheaper choice... |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: MickM on May 16, 2015, 04:21:25 am
Hi;
  The very first thing that the software does on reset is set a pin to keep itself powered on.
If this does not happen then the CPU is not running.
Black bars on the LCD also mean the CPU is not talking to it.

So check for clock at the crystal pins ( I think it's around 1v distorted sine wave).
Look at the reset pin.
Look at power and ground pins, look for ripple.
If your CPU is socketed, unplug it, check the pins then plug it back in.
Look at the address and data lines - are they changing?

You may have a bad pcb, with a short.
Try freezing/heating it.
I had a cap meter that was under etched at the power socket.
Can you program a new chip ?
If smd chip can you change it?

I built a couple, then out of curiosity bought one.
They were all through-hole.

Mick M
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 16, 2015, 04:49:20 am
I check everything lot of times,5volts are there (pins 7,20 ) when I press the button,stops when I release...Some times is working Ok some times not. Board is checked for everything wrong under the microscope,all solderings,joints,etc are perfect,all parts are OK,double and triple checked...

when it refuses to power on shows this pic:

In my experience, you can have solder joints that look absolutely perfect, but make intermittent contact. I would take out the chip and look carefully to make sure that pins are not bent. Next, I would examine the socket because sometimes flux gets inside the holes. After that, insert the chip carefully, making sure that every pin is inside a hole in the socket. This can sometimes be more challenging that it sounds. If all else fails, I would reflow or resolder, beginning with the microcontroller's socket. HTH.

By the way, your phone's camera doesn't seem to be able to take sharp pictures at such close distances.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nassosxlvbros on May 16, 2015, 09:06:50 am
Thanks for the answers!
Sorry for bad the pics,but my mobile don;t like close pics...I'll try a trick on this.
Here some pics fron the pcb.
As you can see everything is clear.The 1nF cap between pins 20-21 is an extra option from me. R15 replaced,but nothing happens..

Title: Re: $20 LCR ESR Transistor checker project
Post by: nassosxlvbros on May 16, 2015, 09:13:04 am
And after all night stay today is working....I don't know for how long of course....
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on May 16, 2015, 09:50:30 am
I reseat the micro chip its too far to the right in the pic. make sure its centered in the socket. If you can replace socket with a machined type even better.

I think thats a poor quality socket and is causing your intermittent failures. every thing else is soldered so should be ok. Having good photos does help us to know what your dealing with.
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: FabioLucca on May 16, 2015, 01:57:32 pm
Hello, I rode the circuit in the simplest way, used a Funduino (AVR 328p 16MHz) removed the LED connected to pin PB5 and changed the capacitor connected to the AREF 1nF, so far so sure, but he is indicating random capacitances including without probes of 100uF  or more 800uF order, besides giving error at the end of "ADJUSTMENT".
Interpreting SELFTEST or ADJUSTMENT data to find the problem?

I used the version "ComponentTester-1.17m" created by Markus Frejek/Karl-Heinz Kübbeler found in https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/) course confurada agreement.
Resistors (680R and 470k) 1% tolerance
LM4040cim 2.5V 0,5% tolerance

OBS .: Text translated by google translator of Portuguese.

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 16, 2015, 03:15:56 pm
Hello, I rode the circuit in the simplest way, used a Funduino (AVR 328p 16MHz) removed the LED connected to pin PB5 and changed the capacitor connected to the AREF 1nF, so far so sure, but he is indicating random capacitances including without probes of 100uF  or more 800uF order, besides giving error at the end of "ADJUSTMENT".
Interpreting SELFTEST or ADJUSTMENT data to find the problem?

Are you powering the tester with a SMPSU? Please try a battery or a linear regulated PSU.

I used the version "ComponentTester-1.17m" created by Markus Frejek/Karl-Heinz Kübbeler found in https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/) course confurada agreement.
Resistors (680R and 470k) 1% tolerance
LM4040cim 2.5V 0,5% tolerance

k-firmware: Karl-Heinz
m-firmware: madires (also a Markus) ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: FabioLucca on May 16, 2015, 04:04:38 pm
Bingo! It worked, it worked perfectly!
Thanks madires!
Title: Re: $20 LCR ESR Transistor checker project
Post by: nassosxlvbros on May 17, 2015, 01:06:05 pm
Yesterday tester makes the same....worked for a dozen times and then stops....As I don't have the necessaries to replace the chip and reproggram it, I must order another meter and waiting ........ :( :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: intrax on May 26, 2015, 09:44:04 pm
thank you for a most enjoyable read. I just took mine apart to see what Atmega was onboard. The lying swine has sent me a 168 not a 328 as stated in this auction.

http://www.ebay.co.uk/itm/181718729730?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.co.uk/itm/181718729730?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

Time to send him an rude email I think. Not happy at this at all.

To Markus and Karl, very impressed with what you have done, as the saying goes Vorsprun… .. :urch Technik indeed.
What seller is your most gracious animal comment referring to? I am curious. .
Title: Re: $20 LCR ESR Transistor checker project
Post by: zomi on May 29, 2015, 11:06:38 am
Thanks tom.

Got it programmed and working ..

Just stuck on how to use makefile.
Wasn't able to sort the battery reading out.

And could someone update me, on the new firmware it has a batch mode enabled from the start.

Title: Re: $20 LCR ESR Transistor checker project
Post by: nassosxlvbros on June 06, 2015, 07:36:45 pm
Update with good news!  :)
Today I receive a new meter kit from Banggood.For a $12.99 was a nice deal.The kit includes everything and a white box.So I asseble it and worked at once.After assembly, I check the "old" chip in the new pcb.It worked just fine.I measure a dozen of caps,about 50 resistors,some leds and 20 transistors.Every time meter powers up correctly.So I check again the old pcb.Measuring Vcc pins (1,7,20) and voila! a wrong smd cap at pin 1 was faulty!! The voltage on ths pin was 1,33V instead of 5 Volts.So I remove the bad cap and meter comes to life again!  :-+ 
Title: Re: $20 LCR ESR Transistor checker project
Post by: pol35 on June 08, 2015, 09:33:42 pm

hello
this tester can do ESR in circuit ?


http://www.ebay.com.au/itm/311343672563 (http://www.ebay.com.au/itm/311343672563)

Is a good esr?
Some recommended seller ? link?

thanks
a greeting
Title: Re: $20 LCR ESR Transistor checker project
Post by: JacquesBBB on June 08, 2015, 09:56:48 pm
hello
this tester can do ESR in circuit ?
http://www.ebay.com.au/itm/311343672563 (http://www.ebay.com.au/itm/311343672563)

Is a good esr?
Some recommended seller ? link?

Beware,  ESR in circuit can be troublesome.
https://www.eevblog.com/forum/beginners/how-to-blow-a-esr-meter/msg679338/#msg679338 (https://www.eevblog.com/forum/beginners/how-to-blow-a-esr-meter/msg679338/#msg679338)

I would recommend in this case to buy a version with the Atmega328  in DIP form on a socket.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on June 09, 2015, 11:13:13 am
Has any one wired a rotary encoder instead of push button?
I have just tried it, it physically fitted in same place,push button of rotary encoder fitted same pcb holes as push button, other unused holes of push button took the outer pins CLK & DATA of encoder, I wired the the centre GND to the GND plane after scratch clear some bare PCB copper.
2 10K SMD resisors connected to CLK and DATA to pullup of 5V and CLK and DATA connected to PD1 and PD3 via series 1K resistors as instructed in TTESTER
manual.
I have attached photos, but have remove the wires going to PD1 PD3, so you can see the silver solder vias for PD1 & PD3 connections. I plan to use 1K smd and kynar wire, this was just a quick test.

Does the software recognize rotary encoder by default ? or do You need to config the option in software and reflash firmware.
It is using firmware 1.12k

Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on June 09, 2015, 02:07:13 pm
Looks like I need to add  CFLAGS += -DWITH ROTARY SWITCH=2 in the make file.
I have downloaded the GNU tarball from for my model board.
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_GM328/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_GM328/)

Is this all i need to run make file just the transistertester.hex and transistertester.eep ?

Will need to do more reading on how to do this, if anyone know a good tutorial or website for more info ?
but its after midnight now so i save this for another night. :)
At least I know its not my hardware at fault.
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on June 09, 2015, 03:50:39 pm
You will need to go through the options adjust them for your hardware. Some testers e.g. use a different divider ratio. Afterwards, you should calibrate your tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on June 10, 2015, 02:37:59 am
 :-DD LOL, I have gone through the make file, need info on actually how to create firmware and flash it.
once i can flash it it be easy to change ratio etc to get it working.
I will try and read out firmware and fuses first and save it if i can, so have a know starting point.

Only experince i have is programing Arduino Nano. (just starting to learn)
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on June 10, 2015, 11:38:05 am
Found this stand alone ISP programmer, uses micro SD card for loading and saving files.
supports FAT16 and FAT32 file systems
-can read, write, verify flash and eeprom memory
-can read, write, verify fusebits and lockbits
-write and read to BIN, HEX, and TXT files
-can set default values of fusebits, erase memories

https://youtu.be/tg67HWwBRlY (https://youtu.be/tg67HWwBRlY)

Website has full write up about design and use.

http://mdiy.pl/uprog-maly-szybki-przenosny-programator-avr-z-sd/?lang=en (http://mdiy.pl/uprog-maly-szybki-przenosny-programator-avr-z-sd/?lang=en)

Plans and firmware in download at end of website.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 10, 2015, 01:22:32 pm
Nice stand-alone programmer! I've started with the BusPirate (quite slow) and switched to an inexpensive Diamex ALL-AVR which supports ISP, PDI and TWI in all flavours. And it survived several low caffeine situations, like ISP header reversed by 180 degrees. If you just need ISP you'll find tons of cheap programmers on the shopping platform of your choice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on June 10, 2015, 02:37:33 pm
Can you point me to a tutorial how to setup avrdude  and winavr and how to use make file to recompile , i am lost in how to setup all this.
I have flashed a Arduino nano to be an ArduinoISP.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on June 10, 2015, 05:26:51 pm
Shortly :)

You must download the complete folder trunk:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?view=tar)

For edit and compilation you can use WinAVR:
http://sourceforge.net/projects/winavr/files/latest/download?source=files (http://sourceforge.net/projects/winavr/files/latest/download?source=files)

Compilation (after editing the Makefile) will run the command "make" (from the command line in the appropriate folder).

For flashing MCU (ATmega328p) using the official ArduinoISP sketch you can use for example this following commands:

For writing only Flash:
Code: [Select]
avrdude -c avrisp -p m328p -P COM3 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a
For writing only Fuses (L=F7, H=D9, E=04):
Code: [Select]
avrdude -c avrisp -p m328p -P COM3 -b 19200 -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m
For writing Flash + Fuses (L=F7, H=D9, E=04):
Code: [Select]
avrdude -c avrisp -p m328p -P COM3 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m
Note:
For proper operation it is important to use a baud rate of 19200 and set the correct number of the communication port for Arduino (-P COMx).
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on June 12, 2015, 05:53:55 am
Quote from: firepower
Thanks for the info, problem I'm having is how to start compile. Have win avr installed. And downloaded the complete trunk files. Do I open a file in winavr ? Main.c? Never done this before, and more I research the more I learn I don't know,  :palm:, I keep looking but any tips from those more experienced may save me a lot of confusion. Only experience I have is programming 8088 and 8051 in asm about 20 years ago.

reading this tutorial

http://www.8051projects.net/files/public/1242392126_2569_FT22383_avr_tutorial.pdf (http://www.8051projects.net/files/public/1242392126_2569_FT22383_avr_tutorial.pdf)

You only need to edit the Makefile included in the appropriate directory. In your case, it is a folder mega328_GM328. For editing use Programmers Notepad - part of the WinAVR.

Then (after editing Makefile) directly from the folder mega328_GM328 you execute compile with the command make - just from the command line you write the command make and press Enter.

The appropriate folder will be added newly compiled files TransistorTester.hex and TransistorTester.eep.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on June 12, 2015, 05:55:01 am
Thanks tom666, I kind of worked it out, i have been thinking i have to compile in an ide or something. but re-reading your earlier post i did exactly as you typed, I can run make now using programmers notepad in winAVR to do the edit,  Now attempting to flash. :-+

Thanks again for explaining again the steps. you have been a big help.  :clap:
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on June 12, 2015, 07:25:55 am
I was able to flash it but it gave error of 103% used and flash failed, reflashed unedited hex and eep. and it working again.
enabling rotary encoder cause it to exceed size of micro rom :(

was not able to save original rom. if anyone has GM328A V1.12 rom can you please upload.

I modified the make file and have rotary encoder working  :-+
had to remove terminal mode and tests 1-7 and store fonts and graphics in eeprom





 
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on June 12, 2015, 08:54:03 am
WinAVR using an old version of AVR-GCC (4.3.3). You must use a newer AVR-GCC (4.8.1 or later).

Unless you have installed the latest version of the Arduino IDE, so just copy and rewrite everything, including subfolders of c:\Program Files (x86)\Arduino\hardware\tools\avr\*.* to folder c:\WinAVR-20100110\.

Attached freshly compiled firmware (CFLAGS += -DWITH_ROTARY_SWITCH=2):
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on June 12, 2015, 09:55:32 am
Thanks again Tom , i will copied arduino avr to win avr, I can run make and flash AVR now.  it made a masssive difference 103% reduced to 85%

Here is the mod wiring on the back of the PCB for the rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lmantuano on June 19, 2015, 01:33:07 pm
G'day!

just joined and already selfishly asking for help (have spent 2 hrs searching though)...  bought and received this :

http://www.ebay.com/itm/261712659541 (http://www.ebay.com/itm/261712659541)

can't get it to work with the onboard AA battery,  won't turn on but with USB power works ok. 

Anyone out there with - or without - the same problem?

thanx

lm
Title: Re: $20 LCR ESR Transistor checker project
Post by: arnonh on June 19, 2015, 01:42:50 pm
I think it is not for normal AA but for cylindrical lithium batteries that have higher voltage i think they are called  18650
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on June 19, 2015, 01:53:57 pm
Quote
just joined and already selfishly asking for help (have spent 2 hrs searching though)
.

Don't worry, that's what just about everyone else's first post was too. :)
Apart from arnonh, who used his first post to help you!  ;D

There seems to be a procedure shown in the 5th photo in the ebay listing for some sort 'battery activating' procedure by shorting a couple of pads with a pair of tweezers.

I must admit, I've thought it was a lithium battery too when I've been glancing through the listings. That same photo seems to make reference to charging. If it was supplied with the Tester and is plain blue like the one in the photo, it probably is a Lithium Ion.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lmantuano on June 20, 2015, 12:25:18 am
OK,  SOLVED, thank you all for your input...
How..?   looked at more ebay listings (searched "M328 tester") and found the answer... AA size 3.7v Battery 14500 - not very common size (imagine putting one or 4/6 of these, by mistake, in place of 1.5/1.2v AAs...!).. 
Since I don't have one, I've tried with an external, more standard, 18650.  I "activated" the battery (shorted two pins as per instructions from yet a diff ebay seller) and all is good!! 
Cute little device, seems to work well, uses SMD 328 but there's no ISP connections..  looks real pretty next to my Quad DSO and Arduino bits and pieces.. Happy!
Grazie, ciao
Luigi M
Title: Re: $20 LCR ESR Transistor checker project
Post by: rr100 on June 20, 2015, 05:11:28 am
USB and LiIon (I presume with charging), I wonder what's next...
Title: Re: $20 LCR ESR Transistor checker project
Post by: lmantuano on June 20, 2015, 05:47:20 am
USB for alternate powering and onboard battery charging..  no data lines connections from what I can see..

Found a flat (rectangular) Li-Ion 1000mAh battery which is the same length of an AA, but 1/3 thinner, fits well and securely in the batt holder, got it charged via USB and works perfectly.

One trick/hint, each time the batt is removed and re-installed, one needs to short the two pads (as shown in the ebay listings) to "re-activate" the batt.. I've actually soldered a micro-switch in that location..

On a slightly diff subject, the Karl-Heinz manual, talks about replacing a certain Zener with the appropriate 2.5v volt-ref diode, as in the original design.. I'm looking into that and, if anyone had practical experience re that, I'd love to hear it..

lm
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 20, 2015, 07:42:06 am
On a slightly diff subject, the Karl-Heinz manual, talks about replacing a certain Zener with the appropriate 2.5v volt-ref diode, as in the original design.. I'm looking into that and, if anyone had practical experience re that, I'd love to hear it..

The TransistorTester supports an optional 2.5V voltage reference connected to PC4. It's used to measure the offset of Vcc and will increase the accuracy. A LT1004 or LM4040 would be fine. Some of the Chinese clones got a simple zener as voltage reference, which makes things worse than better. If you got such a clone remove the zener anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on June 20, 2015, 08:00:00 am
Quote from: lmantuano
On a slightly diff subject, the Karl-Heinz manual, talks about replacing a certain Zener with the appropriate 2.5v volt-ref diode, as in the original design ...

This applies only to older Chinese testers with text display panel. Your tester contains a 2.5V reference.

Quote from: lmantuano
... but there's no ISP connections ...

Your tester has the ability to program the MCU via the ISP. See attached picture from the official discussion forum:
http://www.mikrocontroller.net/topic/248078?page=7#4087263 (http://www.mikrocontroller.net/topic/248078?page=7#4087263)
Title: Re: $20 LCR ESR Transistor checker project
Post by: lmantuano on June 20, 2015, 01:39:18 pm

Excellent, so the ISP connection is done with unused pins from the display daughter board...  better start learning about ISP and programmers then...

thank you all again

lm
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on June 20, 2015, 08:44:50 pm
Anyone have any idea what might be causing mine to display an underscore at the end of the text?

The attached photos demonstrate what is happening, that underscore is always present after the last character.
Title: Re: $20 LCR ESR Transistor checker project
Post by: f1rmb on June 20, 2015, 09:09:19 pm
Hi,

Anyone have any idea what might be causing mine to display an underscore at the end of the text?

The attached photos demonstrate what is happening, that underscore is always present after the last character.

It's just the LCD cursor.

Cheers.
---
Daniel
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on June 20, 2015, 09:18:48 pm
Hi,

Anyone have any idea what might be causing mine to display an underscore at the end of the text?

The attached photos demonstrate what is happening, that underscore is always present after the last character.

It's just the LCD cursor.

Cheers.
---
Daniel

What would cause it to be displayed? It doesn't blink and on other units I've seen that are the same as this one it doesn't show up.
Title: Re: $20 LCR ESR Transistor checker project
Post by: f1rmb on June 20, 2015, 09:40:12 pm
Hi,

Anyone have any idea what might be causing mine to display an underscore at the end of the text?

The attached photos demonstrate what is happening, that underscore is always present after the last character.

It's just the LCD cursor.

Cheers.
---
Daniel

What would cause it to be displayed? It doesn't blink and on other units I've seen that are the same as this one it doesn't show up.

Maybe you may give us more details, e.g what is the firmware version running on your tester.

Cheers.
---
Daniel
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on June 20, 2015, 09:46:07 pm
Hi, its running version 1.11k which is what it came with. Would it be a software thing or can the cursor showing up be hardware related?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 20, 2015, 10:00:59 pm
Hi, its running version 1.11k which is what it came with. Would it be a software thing or can the cursor showing up be hardware related?

I think that there's a problem with the initialization of the LCD module which causes the cursor to be displayed. The cursor should be disabled by default. It's just a single bit in the "display on/off" command.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on June 20, 2015, 10:13:36 pm
I think that there's a problem with the initialization of the LCD module which causes the cursor to be displayed. The cursor should be disabled by default. It's just a single bit in the "display on/off" command.

Hi, so there could be something wrong with the LCD module itself? The LCD board has "1602a v2.0" on the back of it if that makes a difference.

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 20, 2015, 10:35:54 pm
Hi, so there could be something wrong with the LCD module itself? The LCD board has "1602a v2.0" on the back of it if that makes a difference.

Or maybe a flipped bit in the firmware. You could check that with another character display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alex1 on June 20, 2015, 10:48:29 pm
Hi, what does a "flipped bit" mean? Does it mean something went wrong when they flashed the chip with the firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 20, 2015, 11:08:24 pm
Hi, what does a "flipped bit" mean? Does it mean something went wrong when they flashed the chip with the firmware?

Yes, something like that. A flipped bit is a bit which should be 0 but changed into 1 for whatever reason, or vice versa.
Title: Re: $20 LCR ESR Transistor checker project
Post by: coromonadalix on June 21, 2015, 02:22:58 am
Some lcd  dont have u3 the 8 pins soc ic, usually an tc7660 dc dc  converter and caps ...   for the contrast voltage (normally pin 3 of the lcd)  had a few problems in the past until i found that some lcd need an negative voltage, some don't    ....

Maybe thats your problem ??
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 21, 2015, 10:23:38 am
Some lcd  dont have u3 the 8 pins soc ic, usually an tc7660 dc dc  converter and caps ...   for the contrast voltage (normally pin 3 of the lcd)  had a few problems in the past until i found that some lcd need an negative voltage, some don't    ....

Maybe thats your problem ??

I don't think so. Have you seen his pictures a few posts ago? The contrast is fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on June 21, 2015, 11:36:34 am
Quote from: Alex1
Anyone have any idea what might be causing mine to display an underscore at the end of the text?
The attached photos demonstrate what is happening, that underscore is always present after the last character.

I may be wrong. But underscore indicates the uncalibrated tester. This applies to firmware by Karl-Heinz Kübbeler.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 21, 2015, 02:23:02 pm
I may be wrong. But underscore indicates the uncalibrated tester. This applies to firmware by Karl-Heinz Kübbeler.

Ah, I missed that feature (was added in v1.10k).
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on June 24, 2015, 08:32:38 am
I get a C at the end of "testing...C" is that also mean uncalibrated?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on June 24, 2015, 09:30:35 am
Quote from: firepower
I get a C at the end of "testing...C" is that also mean uncalibrated?

I recently received from the author of software this answer:
The character "C" is output on line 2 of the tester, when the capacity measurement begin. It helps a little to analyse, where the time is wasted for the measurement cycle.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 24, 2015, 12:44:01 pm
Quote from: firepower
I get a C at the end of "testing...C" is that also mean uncalibrated?

I recently received from the author of software this answer:
The character "C" is output on line 2 of the tester, when the capacity measurement begin. It helps a little to analyse, where the time is wasted for the measurement cycle.

The measurement of caps with a large µF value needs some time. To indicate that that tester hasn't crashed and that the user should be patient, the 'C' is displayed. Since the capacitance measurement is time critical, a progress bar or whatever wouldn't be easy to implement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JohnPen on June 24, 2015, 08:29:16 pm
Having done the stupid thing of turning down the contrast on my nice new tester I can no longer see anything to bring it back up.  It has the 1.12K s/w and is a GM328 model. Has anyone any suggestions how to recover??
John
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on June 25, 2015, 02:39:46 am
Do you have an AVR ISP, could try erasing eerom that stores the setting , that should default it. Or program default values. I have same model GM328A with smd micro, but have updated my firmware from factory original. When I get home I go through the menu and see how many button presses is needed to get to contrast menu.

Thanks for info about C tom666 and madires

Long press menu:
Transistor
Frequency
f-Generator
10-bit PWM
C+ESR@TP1:3
R+L
Capacitor
Rotary encoder
Selftest
Contrast
Show data
Switch Off
Then Back to Transistor.

Try long press, 9 short presses, long press then many short until  display contrast comes back
It usually dark > light > black > dark etc
Title: Re: $20 LCR ESR Transistor checker project
Post by: JohnPen on June 25, 2015, 12:43:59 pm
Thanks for the info Firepower.  I eventually managed to step correctly to the Contrast  menu item and managed to recover the display.  Because I had problems getting the count right with the appropriate button duration press I cheated a little by using a scope to identify the frequency generator menu setting (pin 1 and 2 for scope) and then the 10 PWM  to get close enough to be sure of getting Contrast.  I had found pressing the button my duration's didn't always get me where I thought I was on the invisible menu!  One thing is certain I am not touching contrast again.  I am a bit surprised that a Master Reset doesn't bring it back to a default display setting it must start there at the very first power up.

Thanks John
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 08, 2015, 06:58:58 pm
I finished mine today. And it works great!
I had some issues with a few shorts on the pcb due to the nature of it's fabrication but I sorted that out (with one fried transistor only) and I loaded both firmwares. I will have to play some more with them, but so far I like it.
I testes some germanium diodes and I have a big Vf compared to my multimeter (~0.6V vs ~0.25) but the rest of the parts check out ok.
I didn't manage to install 0.1% 680R and 470K resistors, I will upgrade those in the future.
I did use a 1702-5002 regulator and lt1004-2.5 voltage reference.
I was interested mainly in having a transistor tester for matching transistors, but the extra features are handy.
I still need to put some conformal coating on the back of the pcb so it doesn't oxidise but I'll do that after I upgrade the resistors.
So far good job and a big thank you to the creators!
Title: Re: $20 LCR ESR Transistor checker project
Post by: montarbo on July 09, 2015, 03:37:12 pm
I finished mine today. And it works great!
I had some issues with a few shorts on the pcb due to the nature of it's fabrication but I sorted that out (with one fried transistor only) and I loaded both firmwares. I will have to play some more with them, but so far I like it.
I testes some germanium diodes and I have a big Vf compared to my multimeter (~0.6V vs ~0.25) but the rest of the parts check out ok.
I didn't manage to install 0.1% 680R and 470K resistors, I will upgrade those in the future.
I did use a 1702-5002 regulator and lt1004-2.5 voltage reference.
I was interested mainly in having a transistor tester for matching transistors, but the extra features are handy.
I still need to put some conformal coating on the back of the pcb so it doesn't oxidise but I'll do that after I upgrade the resistors.
So far good job and a big thank you to the creators!


Nice work.
Mind sharing the PCB file in PDF with 1:1 scale and part list. Thanks ahead.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 09, 2015, 05:05:10 pm
Just a brief update about the m-firmware. There will be two editions in the future. The current firmware, supporting ATmega168/328 with a 2x16 HD44780 character display, will be called classic edition. The second edition (no name yet) supports the ATmega328 with character and graphic displays. For the start, HD44780 and ST7565R drivers are included. The UI automatically adapts to the available number of lines. Later on I'll add support for ATmega644/1284, fancy pinout and additional display controllers. If you like to support the development, I would appreciate samples of LCD modules with other controllers. V1.18m of both editions will be released within the next week or so.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on July 09, 2015, 06:55:31 pm
Later on I'll add support for ATmega644/1284, fancy pinout and additional display controllers.

Are there pcb's available for these?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 09, 2015, 08:01:40 pm
Later on I'll add support for ATmega644/1284, fancy pinout and additional display controllers.

Are there pcb's available for these?

Not yet, AFAIK.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 10, 2015, 01:52:05 am
I finished mine today. And it works great!
I had some issues with a few shorts on the pcb due to the nature of it's fabrication but I sorted that out (with one fried transistor only) and I loaded both firmwares. I will have to play some more with them, but so far I like it.
I testes some germanium diodes and I have a big Vf compared to my multimeter (~0.6V vs ~0.25) but the rest of the parts check out ok.
I didn't manage to install 0.1% 680R and 470K resistors, I will upgrade those in the future.
I did use a 1702-5002 regulator and lt1004-2.5 voltage reference.
I was interested mainly in having a transistor tester for matching transistors, but the extra features are handy.
I still need to put some conformal coating on the back of the pcb so it doesn't oxidise but I'll do that after I upgrade the resistors.
So far good job and a big thank you to the creators!


Nice work.
Mind sharing the PCB file in PDF with 1:1 scale and part list. Thanks ahead.

I attached the brd file. I think you should find the parts with values in it.
One piece of advice, I used 2.5mm pitch non polarised caps. If you want to use 5mm ones just be sure they have longer leads.
I can't even remember how I started this project, I may have gotten the eagle project and modify it.
Also do size the contrast resistor according to your LCD. (it's noted as 470ohms in the project, RLCD2)
Anyway, have fun.
PS I can't remember what the second set of connectors is for (Pin 26). I don't care, I really need this gizmo to test transistors mostly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on July 10, 2015, 07:21:33 am
I like to do things as simple as possible and so I decided for this variant of tester. This is a version of my PCB design in minimal form (VSCT = Very Simple Componet Tester  :)).

Features of Tester are preserved and identical to the standard version, but without auxiliary power circuit - it is necessary to use manual switching power on and off. I recommend compile software with blocked the auto power off (#CFLAGS += -DPOWER_OFF) - disable auto power off.

Crystal and 2.5V reference voltage source (which may to some extent contribute to improvements in measurement precision) has been omitted.

LCD contrast trimmer 10k was replaced by 2k7 resistor connected between the GND and the LCD contrast adjustment pin.

I chose commonly available LDO stabilizer 78L05.

Fuse setting:
ATmega168, ATmega168p:
lfuse:0xe2 hfuse:0xdc efuse:0x01 (0xf9)

ATmega328, ATmega328p:
lfuse:0xe2 hfuse:0xd9 efuse:0x04 (0xfc)
Title: Re: $20 LCR ESR Transistor checker project
Post by: montarbo on July 11, 2015, 12:44:05 pm
I think you should find the parts with values in it.

Well thanks a lot for sharing the brd file, any chance to get one with top view? just to get the parts list would be appreciated.

BR
Title: Re: $20 LCR ESR Transistor checker project
Post by: bob808 on July 11, 2015, 12:45:12 pm
Just enable all the layers :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: montarbo on July 11, 2015, 09:46:08 pm
Just enable all the layers :)


Thanks again for the info, but there is a problem with this file, can you double check the GND, which layer should it be.
As of I save it as PDF the whole gnd is missing, same in Eagle. In your pic the traces go between the GND while in the attached file its missing. (http://)

Title: $20 LCR ESR Transistor checker project
Post by: bob808 on July 12, 2015, 09:09:23 am
Press on the Ratsnest button before exporting.
Also when you are looking at the board as you open my file, you are basically seeing the board from the top layer. All the traces are on the backside of the board. So take that into account when you are printing the layout.
Title: Re: $20 LCR ESR Transistor checker project
Post by: montarbo on July 12, 2015, 12:13:53 pm
Thanks a ton for all the info, I've never used Eagle before, that's why i asked for the pdf file at first place. But now I'm trying to work with Eagle´, better late than never!!

You mean i should chose the mirrored version when exporting to pdf?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 12, 2015, 12:49:45 pm
You mean i should chose the mirrored version when exporting to pdf?

You would need the mirrored output only for the top layer, in case it's a double sided PCB.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on July 12, 2015, 01:17:00 pm
For you montarbo:
Title: Re: $20 LCR ESR Transistor checker project
Post by: montarbo on July 12, 2015, 02:10:52 pm
Thanks ALL for help and great work.

BR
Title: Re: $20 LCR ESR Transistor checker project
Post by: wd5gnr on July 12, 2015, 11:02:19 pm
Thingiverse has a nice "bento box" for the exact model I have (GM328A). Here's my build of it: http://www.thingiverse.com/make:147679 (http://www.thingiverse.com/make:147679)

(https://thingiverse-production-new.s3.amazonaws.com/renders/cc/84/2c/5f/7b/IMG_0278_preview_featured.JPG)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vic2r on July 13, 2015, 03:27:15 pm
For owners of this tester which is offered on ebay under the designation as "LCR-T3" or "LCR-T4 Transistor Tester" I offer a way to update firmware (v1.12k r453 EN). Devices have identical PCB, but slightly different G-LCD with matching operation thanks to compatibility with the driver ST7565. Update works on both versions of this tester. However, attention should be given to the fact that the ISP connector from the parts is mirrored. For this purpose I have pieced together a simple detachable :) adapter enabling the MCU to program without arranging the auxiliary ISP connector (see attached pictures). Many thanks to Roland Elmiger (hb9gaa) from the official discussion forum for providing the schematic diagram (http://www.mikrocontroller.net/topic/248078?page=6#3784106).

Do you still have the schematic for this design sir, 'cause all i see on the link to the diagram is 16x2 lcd only.  :-// I translated it to english and read it all again then look for the  Roland Elmiger (hb9gaa)name and there is none, now my head is banging on a brick wall  |O  If you still have it or someone has it, can someone please upload it on jpg file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on July 14, 2015, 06:25:56 am
Do you still have the schematic for this design sir, 'cause all i see on the link to the diagram is 16x2 lcd only.  :-// I translated it to english and read it all again then look for the  Roland Elmiger (hb9gaa)name and there is none, now my head is banging on a brick wall  |O  If you still have it or someone has it, can someone please upload it on jpg file.

Link to registered users:
https://www.mikrocontroller.net/topic/248078?page=14#3784106 (https://www.mikrocontroller.net/topic/248078?page=14#3784106)

Link to unregistered users:
https://www.mikrocontroller.net/topic/248078?page=6#3784106 (https://www.mikrocontroller.net/topic/248078?page=6#3784106)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Overtuner on July 15, 2015, 08:08:16 am
Later on I'll add support for ATmega644/1284, fancy pinout and additional display controllers.
sounds good. based on the schematics from Karl-Heinz and Nick L. (Docu chapter 2.7)?
I would suggest some more circuitry
- what about a DC boost converter to 40volts (some simple LT3467 stuff)
- integrated LiPo charger/booster
- and if so, recharging by USB - so what, put a cheap USB/UART- Bridge onboard for future use with external piece of Software...
- Display. think about those cheap (10$) ST7735R based 1.8inch TFT (https://www.adafruit.com/products/618)

I could also design a pcb - especially I'm thinking about a size, which will fit in a nice case (http://www.bopla.de/en/enclosure-technology/product/bos-streamline.html). I hate those 'naked' stuff on my bench  8)
cheers
Lutz
Title: Re: $20 LCR ESR Transistor checker project
Post by: Overtuner on July 25, 2015, 01:56:34 pm
ok, a quick'n dirty prototype is born.

- based on a chinese T4
- built into a Hammond case 1553D-BAT
- with rotary encoder
- with 2mm Banana Jacks
- Textool socket (desoldered from original) glued into top cover


and - there's a lot of space in those type of box.
I created a eagle .lbr with the PCB Layout from Hammond's datasheet. stay tuned ;-)

Lutz
Title: Re: $20 LCR ESR Transistor checker project
Post by: Overtuner on July 25, 2015, 08:03:09 pm
Later on I'll add support for ATmega644/1284, fancy pinout and additional display controllers. If you like to support the development, I would appreciate samples of LCD modules with other controllers. V1.18m of both editions will be released within the next week or so.

do You need one of those cheep ILI9341 based new 2.2inch TFT (http://www.elecfreaks.com/store/22-tft-lcd-tft0122sp-p-672.html) - I've one over...

I'm sure, I will use them for my new layout, the fit almost perfectly in the case  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 26, 2015, 10:33:21 am
do You need one of those cheep ILI9341 based new 2.2inch TFT (http://www.elecfreaks.com/store/22-tft-lcd-tft0122sp-p-672.html) - I've one over...

I'm sure, I will use them for my new layout, the fit almost perfectly in the case  ;D

I've sent you a PM.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lordhex on July 27, 2015, 02:04:47 am
Hello,

I've purchased a similar Transistor Tester from -- http://www.amazon.com/gp/product/B00OOQC2E8psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00 (http://www.amazon.com/gp/product/B00OOQC2E8psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00) -- GM328 LCD Display Transistor Tester using the latest 2014 version V1.11 software, Atmega328 chip based on this project. Somehow I went into the "Contrast" menu then I've pressed the test button and it took
the "Contrast" all the way down  |O , now I cannot see anything on the display  |O |O |O.
Would anyone be able to tell me how to reset it back to default?
I've searched all the forums since this morning and could not find any answer
to my question. There are lots of Chinese knock offs and I'm not sure which one is which.

Many thanks in advance.
Catalin
Title: Re: $20 LCR ESR Transistor checker project
Post by: JohnPen on July 27, 2015, 08:09:22 am
I had the same problem Catalin.  If you look on page 72 of this thread you will see the advice from Firepower and also my solution to locating the correct menu selection to bring the contrast back up again.  It seems strange that the module doesn't have a factory type rest as when initially 'fired up' it works!
John
Title: Re: $20 LCR ESR Transistor checker project
Post by: rstor22 on July 27, 2015, 02:24:13 pm
Would these AVR Transistor testers (such as the ones found on eBay) test leakage (Igss and Idss)  for JFETs ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: lordhex on July 28, 2015, 01:45:33 am
I had the same problem Catalin.  If you look on page 72 of this thread you will see the advice from Firepower and also my solution to locating the correct menu selection to bring the contrast back up again.  It seems strange that the module doesn't have a factory type rest as when initially 'fired up' it works!
John

Thank you so much John for replying to my problem.
For the life of me, I cannot get into that menu tried the "blind" method, also tried to see (with an oscilloscope) where the signals are sent to the LCD from the Atmega could not find much. I have to say I don't know anything about microcontrollers, I'm more of an audio/video/Linux/Mac kind of guy.

Much appreciated any help you can offer. I've attached a picture with the culprit.
Thank you,
Catalin

Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on July 28, 2015, 07:59:12 am
ok, a quick'n dirty prototype is born.

- based on a chinese T4
- built into a Hammond case 1553D-BAT
- with rotary encoder
- with 2mm Banana Jacks
- Textool socket (desoldered from original) glued into top cover


and - there's a lot of space in those type of box.
I created a eagle .lbr with the PCB Layout from Hammond's datasheet. stay tuned ;-)

Lutz

Do you want to share it? Please, would be very nice to hace it too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Overtuner on July 28, 2015, 08:48:31 am
Do you want to share it? Please, would be very nice to hace it too.
of course. all the stuff I create is open source  ;D

I had found a .lbr with other hammond boxes somewhere in the web (unfortunately I don't remember where)
and added the 1553D Variant.

at the moment I'm playing around with the circuitry for my "new" moel of ttester, but quite in early beta state and not finished yet.
m1284, 2.2inch TFT (maybe 2.4 inch with Touch), FT232RL, Lipo with charger(MCP73831), lipo to 5V boost, 3v3 for display, 5v to 40V boost, micro-USB, mini-sd-card, encoder, ...

cheers
Lutz


Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on July 28, 2015, 10:32:37 am
Do you want to share it? Please, would be very nice to hace it too.
of course. all the stuff I create is open source  ;D

I had found a .lbr with other hammond boxes somewhere in the web (unfortunately I don't remember where)
and added the 1553D Variant.

at the moment I'm playing around with the circuitry for my "new" moel of ttester, but quite in early beta state and not finished yet.
m1284, 2.2inch TFT (maybe 2.4 inch with Touch), FT232RL, Lipo with charger(MCP73831), lipo to 5V boost, 3v3 for display, 5v to 40V boost, micro-USB, mini-sd-card, encoder, ...

cheers
Lutz

Oh, that's going to be a nice improvement!

Are those ESR meters cheap to get one and use it for the case?

Are you basing your design on the Markus' Microcontroller.net (https://www.mikrocontroller.net/svnbrowser/transistortester/) one? What firmware are you using?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 28, 2015, 01:27:43 pm
at the moment I'm playing around with the circuitry for my "new" moel of ttester, but quite in early beta state and not finished yet.
m1284, 2.2inch TFT (maybe 2.4 inch with Touch), FT232RL, Lipo with charger(MCP73831), lipo to 5V boost, 3v3 for display, 5v to 40V boost, micro-USB, mini-sd-card, encoder, ...

Sounds very interesting! It seems I have to think about how to add touch screen support to the firmware ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Overtuner on July 28, 2015, 06:07:51 pm
Sounds very interesting! It seems I have to think about how to add touch screen support to the firmware ;)
oh-yeah!  8)
hope, I'll get the 2.4" samples with touch (ILI9341 based) next few days and can ship them to you...

and: also the cheap chinese non-touch 2.2inch and 1.8inch tft's have 99% the same controller....
Title: Re: $20 LCR ESR Transistor checker project
Post by: JohnPen on July 28, 2015, 08:25:58 pm
Hi Catalin,

The method I used was as follows:

I eventually managed to step correctly to the Contrast  menu item and managed to recover the display.  Because I had problems getting the count right with the appropriate button duration press I cheated a little by using a scope to identify the frequency generator menu setting (pin 1 and 2 for scope) and then the 10 PWM  to get close enough to be sure of getting Contrast.  I had found pressing the button my duration's didn't always get me where I thought I was on the invisible menu!

My module is identical to your one in the picture you attached. The pins 1 and 2 were those on the ZIF socket where you insert components you wish to test. If you get your button pushing right you should see a 100Khz signal on a scope from the signal generator selection. (This gives one some confidence in one's button pressing accuracy!) The next short push should get you a Pulsed output visible on the scope.  Then it is 6 more short pushes to reach Contrast. Follow this with a long press then repeated short presses to hopefully bring the contrast back up.  It didn't work the first time I tried but button pushing with no visible responses isn't easy hence the scope to try and help.

Best of luck Contrast adjustment is now a no go area!

John
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on July 28, 2015, 10:23:14 pm
For owners of this tester which is offered on ebay under the designation as "LCR-T3" or "LCR-T4 Transistor Tester" I offer a way to update firmware (v1.12k r453 EN). Devices have identical PCB, but slightly different G-LCD with matching operation thanks to compatibility with the driver ST7565. Update works on both versions of this tester. However, attention should be given to the fact that the ISP connector from the parts is mirrored. For this purpose I have pieced together a simple detachable :) adapter enabling the MCU to program without arranging the auxiliary ISP connector (see attached pictures). Many thanks to Roland Elmiger (hb9gaa) from the official discussion forum for providing the schematic diagram (http://www.mikrocontroller.net/topic/248078?page=6#3784106).

Hello Tom666 and every other member!

I am new on this forum and not too experienced, but I try. I own one of these referred to by Tom666 and am trying to flash it with an Arduino Uno via the Avrisp connection. I made myself a cable and everything seems to be communicating, but when I send the avrdude commands, I get a message the following messages:

C:\WinAVR-20100110\bin>avrdude -c avrisp -p m328p -P COM6 -b 19200 -e -U flash:w
:"TransistorTester.hex":a -U eeprom:w:"Transistor.eep":a -U lfuse:w:0xF7:m -U hf
use:w:0xD9:m -U efuse:w:0x04:m -v

avrdude: Version 5.10, compiled on Jan 19 2010 at 10:45:23
         Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/ (http://www.bdmicro.com/)
         Copyright (c) 2007-2009 Joerg Wunsch

         System wide configuration file is "C:\WinAVR-20100110\bin\avrdude.conf"


         Using Port                    : COM6
         Using Programmer              : avrisp
         Overriding Baud Rate          : 19200
         AVR Part                      : ATMEGA328P
         Chip Erase delay              : 9000 us
         PAGEL                         : PD7
         BS2                           : PC2
         RESET disposition             : dedicated
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page
      Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  Max
W   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ---
-- ---------
           eeprom        65     5     4    0 no       1024    4      0  3600  36
00 0xff 0xff
           flash         65     6   128    0 yes     32768  128    256  4500  45
00 0xff 0xff
           lfuse          0     0     0    0 no          1    0      0  4500  45
00 0x00 0x00
           hfuse          0     0     0    0 no          1    0      0  4500  45
00 0x00 0x00
           efuse          0     0     0    0 no          1    0      0  4500  45
00 0x00 0x00
           lock           0     0     0    0 no          1    0      0  4500  45
00 0x00 0x00
           calibration    0     0     0    0 no          1    0      0     0
 0 0x00 0x00
           signature      0     0     0    0 no          3    0      0     0
 0 0x00 0x00

         Programmer Type : STK500
         Description     : Atmel AVR ISP
         Hardware Version: 2
         Firmware Version: 1.18
         Topcard         : Unknown
         Vtarget         : 0.0 V
         Varef           : 0.0 V
         Oscillator      : Off
         SCK period      : 0.1 us

avrdude: stk500_program_enable(): protocol error, expect=0x14, resp=0x50
avrdude: initialization failed, rc=-1
         Double check connections and try again, or use -F to override
         this check.

avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51

avrdude done.  Thank you.

Can anybody help, please!

Thank you all and what a great forum!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on July 28, 2015, 10:27:21 pm
Oh and I forgot, another question.

When you program the Yellow transistor tester, does it have to be powered by the 9V battery or it gets its power from the ISP connection?

Many thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on July 29, 2015, 01:41:06 am
Well, what do you know, I finally found my problem and thought I should share it with others in case you come across the same problem.

Using the Arduino Uno as an AVRISP loader, you connect all pins of the ISP on the Uno to the ISP of the Yellow Transistor Tester, except for Reset that you plug from the ISP of the Transistor Tester to pin (hole) #10 of the digital side of the Uno, and voilà it works just fine!

Thanks again to all that have read me and best regards,

Raymond
Title: Re: $20 LCR ESR Transistor checker project
Post by: amirtebyan on July 30, 2015, 04:01:10 am
Hi
I want to add voltmeter with auto detection of positive and negative voltages (-30 ~ +30 or -50 ~ +50)
I found this circuit useful
(http://www.cq.cx/pics/int-read--15-15-v.png)
for this circuit :
 Vadc = (Vmeasured + 15)/6, which means that Vadc goes from 0 to 5 V as Vmeasured goes from -15 to +15 V, which is what we want.

for more detail : http://www.cq.cx/interface.pl#6 (http://www.cq.cx/interface.pl#6)

What is your ideas about using this circuit (connecting Vext in tester to Vmeasured and using buffer circuit in Vext line for protection)?

(http://www.eecs.tufts.edu/~dsculley/tutorial/opamps/opAmpBuffer.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Overtuner on July 30, 2015, 05:43:33 am
Hi
I want to add voltmeter //
a simple voltage measurement is already implemented.
see section 2.2.3 (Measurement of zener voltage above 4 Volt) in Karl-Heinz Kuebbeler's reference manual

//with auto detection of positive and negative voltages (-30 ~ +30 or -50 ~ +50)
well - for negative and /or AC measurement there's a need for more circuitry.
If there's reallly a need for this, I'd look at some schematics of well known and tested "classic" multimeters and "steal" some ideas  ::)

Title: Re: $20 LCR ESR Transistor checker project
Post by: amirtebyan on July 30, 2015, 06:12:50 am
Hi
I want to add voltmeter //
a simple voltage measurement is already implemented.
see section 2.2.3 (Measurement of zener voltage above 4 Volt) in Karl-Heinz Kuebbeler's reference manual

thank you for your response.

Yes I read that section but he say:
"You can only measure positiv DC voltages up to 50V. You have also to respect the correct polarity."

I want to add voltmeter  feature like digital voltmeters to Tester. (when I change two prob a negative sign shown.)

well - for negative and /or AC measurement there's a need for more circuitry.

Do you think This circuit isn't sufficient for that purpose?


 can you please explain more about other circuits?
thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on July 31, 2015, 02:29:35 pm
Hello,

A question for Madires:

What are the features of the version 1.18M - are they listed anywhere? Is the ST7565 display version available and will it work with the Mega_T4_T5_st7565 version of the transistor Tester?

Also, does the 1.18M version have the Esr in circuit function?

Finally, how does it compare to the 1.12K version - major differences?

Many thanks,

Raymond
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 31, 2015, 03:48:44 pm
What are the features of the version 1.18M - are they listed anywhere? Is the ST7565 display version available and will it work with the Mega_T4_T5_st7565 version of the transistor Tester?

Also, does the 1.18M version have the Esr in circuit function?

Finally, how does it compare to the 1.12K version - major differences?

The "trendy edition" supports the ST7565R controller, but I haven't tested it with the clone you've mentioned, because I don't got that one. The features are about the same and in-circuit ESR checks are supported too. The source code archive includes a readme file with all details.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 01, 2015, 08:49:02 pm
Hello Everyone,

I am in deep trouble, as I had programmed my T3_T4_ST7585 transistor tester with Tom666 compilation and instructions. I thought it was great!

So I decided to compile and upload vers 1.18m of Madires (trendy edition)...all I got was a blank screen, nothing. So i tried re uploading the Tom666 version, but avrdude gives me all sorts of error messages, saying it can't read the Lfuse so it is aborting, device is not right device, etc. etc.

Have I bricked my transistor tester?

Any help would be most appreciated! Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on August 01, 2015, 08:58:27 pm
Most likely you screwed up the fuse bits, and the controller now is set for use with an external crystal. Try to connect a crystal to reprogram the fuse bits properly or connect a function generator to the XTAL1 bin on the controller. Avrdude has the -B option to specify the SPI clock rate. For a 500kHz rescue clock, an appropriate example might be `avrdude -c usbtiny -p attiny861 -B250 -U hfuse:w:0xBITS:m -U lfuse:w:0xBITS:m`, look up the proper fuse bits for the software and your controller. Use that (maybe with the -f force option). It that doesn't work, you need a high voltage programmer. If that again doesn't work, you bricked it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 01, 2015, 09:06:26 pm
I am in deep trouble, as I had programmed my T3_T4_ST7585 transistor tester with Tom666 compilation and instructions. I thought it was great!

The "trendy edition v1.18m" supports  ST7565R and HD44780, not ST7585. The k-firmware does neither. Sorry!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 01, 2015, 10:44:28 pm
Most likely you screwed up the fuse bits, and the controller now is set for use with an external crystal. Try to connect a crystal to reprogram the fuse bits properly or connect a function generator. Avrdude has the -B option to specify the SPI clock rate. For a 500kHz rescue clock, an appropriate example might be `avrdude -c usbtiny -p attiny861 -U hfuse:w:0xBITS:m -U lfuse:w:0xBITS:m`, look up the proper fuse bits for the software and your controller. Use that (maybe with the -f force option). It that doesn't work, you need a high voltage programmer. If that again doesn't work, you bricked it.

Can you maybe point me in the right direction, how do I connect a crystal? I am using an Arduino Uno as a avrsip programmer...I have a few crystals that I can try , but not sure where and how to connect it?

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 01, 2015, 10:46:52 pm
I am in deep trouble, as I had programmed my T3_T4_ST7585 transistor tester with Tom666 compilation and instructions. I thought it was great!

The "trendy edition v1.18m" supports  ST7565R and HD44780, not ST7585. The k-firmware does neither. Sorry!

But the k firmware that Tom666 posted worked perfectly. How do I ressurect my "bricken" transistor tester? I have a copy of the original firmware that came with it, but avrdude refuses to let me do anything??

Tks
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 01, 2015, 10:49:47 pm
Most likely you screwed up the fuse bits, and the controller now is set for use with an external crystal. Try to connect a crystal to reprogram the fuse bits properly or connect a function generator. Avrdude has the -B option to specify the SPI clock rate. For a 500kHz rescue clock, an appropriate example might be `avrdude -c usbtiny -p attiny861 -U hfuse:w:0xBITS:m -U lfuse:w:0xBITS:m`, look up the proper fuse bits for the software and your controller. Use that (maybe with the -f force option). It that doesn't work, you need a high voltage programmer. If that again doesn't work, you bricked it.

I have the proper fuse bits that Tom666 posted earlier on for this transistor tester. Not sure what a function program generator is and a high voltage programmer either?

Please help! Thank u!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 01, 2015, 10:52:22 pm
Here is the last command I sent with avrdude:

C:\WinAVR-20100110\bin\trunk\mega328_T3_T4_st7565>avrdude -c avrisp -p m328p -P
COM5 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"Transistor.eep
":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m -v -F

avrdude: Version 6.1, compiled on Mar 13 2014 at 00:09:49
         Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/ (http://www.bdmicro.com/)
         Copyright (c) 2007-2014 Joerg Wunsch

         System wide configuration file is "C:\WinAVR-20100110\bin\avrdude.conf"


         Using Port                    : COM5
         Using Programmer              : avrisp
         Overriding Baud Rate          : 19200
         AVR Part                      : ATmega328P
         Chip Erase delay              : 9000 us
         PAGEL                         : PD7
         BS2                           : PC2
         RESET disposition             : dedicated
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page
      Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  Max
W   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ---
-- ---------
           eeprom        65    20     4    0 no       1024    4      0  3600  36
00 0xff 0xff
           flash         65     6   128    0 yes     32768  128    256  4500  45
00 0xff 0xff
           lfuse          0     0     0    0 no          1    0      0  4500  45
00 0x00 0x00
           hfuse          0     0     0    0 no          1    0      0  4500  45
00 0x00 0x00
           efuse          0     0     0    0 no          1    0      0  4500  45
00 0x00 0x00
           lock           0     0     0    0 no          1    0      0  4500  45
00 0x00 0x00
           calibration    0     0     0    0 no          1    0      0     0
 0 0x00 0x00
           signature      0     0     0    0 no          3    0      0     0
 0 0x00 0x00

         Programmer Type : STK500
         Description     : Atmel AVR ISP
         Hardware Version: 2
         Firmware Version: 1.18
         Topcard         : Unknown
         Vtarget         : 0.0 V
         Varef           : 0.0 V
         Oscillator      : Off
         SCK period      : 0.1 us

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.05s

avrdude: Device signature = 0x00ffff
avrdude: Expected signature for ATmega328P is 1E 95 0F
avrdude: safemode: Verify error - unable to read lfuse properly. Programmer may
not be reliable.
avrdude: safemode: To protect your AVR the programming will be aborted

avrdude done.  Thank you.

Tks,

Raymond
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 02, 2015, 12:46:24 am
Well here I am again.

Read this in another forum:

"As someone mentioned, the first chip you may be able to fix by passing -B10 to avrdude. In order to program an AVR, the programmer has to be running at a slower speed than the chip you're programming is running. The fuses you have set cause the chip to run at 1Mhz using the internal clock, and -B10 will cause it to go slower (the defaults are suitable for programming a chip that is running faster than 4MHz)."

So i passed a -B10 command to avrdude and voila! it got my transistor tester back. The fuses were reset and I was able to reflash it with Tom666's compiled version of 1.12K.

Now for Madires: how do I get version 1.18m working on this transistor tester?

Many thanks to all of you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 02, 2015, 11:03:33 am
But the k firmware that Tom666 posted worked perfectly.

Is the ST7585 compatible with the ST7565R? I haven't checked the datasheet for the ST7585. Or have you messed up the 6 with the 8?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 02, 2015, 01:37:39 pm
Hello Madires,

No, I think you are right, I did mix up the 6 and the 8. The ST7565R is a 65 x 132 Dot Matrix LCD controller/driver, while the ST7585 is a 66 x 102 Dot Matrix LCD controller/driver.

Somehow, (I think it might be Tom666) got the ST7585 to work with the 1.12K version of Karl Heinz. I'm really not experienced enough to port that code in the version 1.18m, do I guess we'll have to wait for if ever someone with knowledge and experience succeeds in doing it.

As you mentionned Madires, the features of ver. 1.12K and 1.18m are very similar, however I would have liked to compare. I am getting next week a more standard (2 line display) transistor tester in kit form (I have to solder it first) and I think I will try the 1.18m version on that one once it is completed. It is the kit format from Banggood.com.

Best regards,

Raymond

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 03, 2015, 11:35:41 am
Somehow, (I think it might be Tom666) got the ST7585 to work with the 1.12K version of Karl Heinz. I'm really not experienced enough to port that code in the version 1.18m, do I guess we'll have to wait for if ever someone with knowledge and experience succeeds in doing it.

You don't to have port any code, just check the settings of the working k-firmware's Makefile and config.h and adapt the corresponding #defines in the m-firmware's config.h. There are several settings for the LCD module and maybe the pin assignment needs some tweaks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 03, 2015, 02:38:25 pm
... how do I get version 1.18m working on this transistor tester? ...

Attached files contain compiled software for your T3, T4 tester with ST7565 controller (not ST7585). It was necessary to make the following modifications to the source code (files "config.h" and "ST7565R_SPI.c"):
- edit mappings ports of MCU and LCD
- cosmetic changes (LCD_FLIP_Y, LCD_CONTRAST, LCD_OFFSET_X)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 03, 2015, 02:58:40 pm
Attached files contain compiled software for your T3, T4 tester with ST7565 controller (not ST7585). It was necessary to make the following modifications to the source code (files "config.h" and "ST7565R_SPI.c"):
- edit mappings ports of MCU and LCD
- cosmetic changes (LCD_FLIP_Y, LCD_CONTRAST, LCD_OFFSET_X)

Thanks! I'll add your config.h settings to the next version. The change in ST7565R_SPI.c isn't necessary, simply put a "//" in front of "#define LCD_OFFSET_X" to disable the display offset in the x direction.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 04, 2015, 01:52:36 am
Thank you very much Tom666!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 04, 2015, 01:58:48 am
Question Tom666:

There is a file in the compiled version with 3 sets of fuses. I'm sort of worried about playing around with fuses, so do I need to change any fuses, or can I just upload the trendy 1.18m Hex and EEp files to get it going?

Thank you,

Raymond
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 04, 2015, 05:08:25 am
Do not modify fuses - leave the original values. Only write flash and eeprom.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 04, 2015, 03:02:07 pm
Questions for Madires:

Hello. I tested the version 1.18m on the T3_T4 ST 7565 tester and it seems to work well. However 2 questions:

1) Is it normal that for some capacitors, there is no ESR value shown (example 470uf capacitor, brand new) ?
2) For the ESR in circuit mode from the menu, is there a way to have it the tester to probe without having to press the button?

Also, my probes are soldered on pins 1 and 3, so I guess if I change the Esr in circuit function to use pin 3 instead of pin 2, that should be ok?

Many thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 04, 2015, 09:19:05 pm
1) Is it normal that for some capacitors, there is no ESR value shown (example 470uf capacitor, brand new) ?

Have you run the self-adjustment? When the tester measures an ESR value lower than the internal resistance of the probe pins, the ESR value is considered invalid.

2) For the ESR in circuit mode from the menu, is there a way to have it the tester to probe without having to press the button?

Not at the moment.

Also, my probes are soldered on pins 1 and 3, so I guess if I change the Esr in circuit function to use pin 3 instead of pin 2, that should be ok?

Yes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 09, 2015, 12:49:09 am
Hello everyone,

Just got this tester in kit form from BangGood:

http://www.banggood.com/86-Plastic-Shell-DIY-Meter-Tester-Kit-For-Capacitance-ESR-Inductance-p-956240.html (http://www.banggood.com/86-Plastic-Shell-DIY-Meter-Tester-Kit-For-Capacitance-ESR-Inductance-p-956240.html)

Pretty good kit, but it doesn't have the latest release of the firmware. I saw on that there seems to be a realease 508 of Karl Heinz's v 1.12K here:

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/?pathrev=508 (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/?pathrev=508)

So my question is which version do I use, do I simply use the default directory for this 2 line display tester?

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 09, 2015, 03:49:13 am
Sorry, but I have another question for this BangGood transistor tester.

How can I make a backup copy of the flash and eeprom ...I've tried with AVRDUDE with the following commands:

avrdude -c avrisp -p m328p -P COM5 -b 19200  -U flash:r:"TransistorTesterbk.hex":i
avrdude -c avrisp -p m328p -P COM5 -b 19200  -U flash:r:"TransistorTesterbk.hex":a
avrdude -c avrisp -p m328p -P COM5 -b 19200  -U flash:r:"TransistorTesterbk.hex"

But I either get a file with 71 bytes in it or 0..I can't dump the flash memory...haven't tried the EEprom yet.

Any help would be appreciated.

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 09, 2015, 10:52:58 am
So my question is which version do I use, do I simply use the default directory for this 2 line display tester?

Use the folder "mega328".

How can I make a backup copy of the flash and eeprom ...

It's unnecessary, because is used the firmware by Karl-Heinz Kübbeler. I think, these testers are currently sold with older revision of a test version 1.12k. Some time ago it was used old v1.05k.

However, if you want, try the following command:
Code: [Select]
avrdude -c avrisp -p m328p -P COM5 -b 19200 -U flash:r:"TransistorTester.hex":a -U eeprom:r:"TransistorTester.eep":a
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 09, 2015, 11:22:24 am
Thank you for the info Tom666.

I was just wanting to have a backup of the installed firmware before flashing it. Also I am trying to test ans ISP connector that I made for this transistor tester as there is none on the board.

I tried your command with the following and here is what it tells me...also creates a file of 0 bytes:

avrdude -c avrisp -p m328p -P COM5 -b 19200 -U flash:r:"TTesterbk.hex":a

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.05s

avrdude: Device signature = 0x1e950f
avrdude: reading flash memory:

Reading | ################################################## | 100% 24.49s

avrdude: writing output file "TTesterbk.hex"
avrdude: error opening TTesterbk.hex: No such file or directory
avrdude: output file TTesterbk.hex auto detected as invalid format
avrdude: invalid output file format: -1
avrdude: write to file 'TTesterbk.hex' failed

avrdude: safemode: Fuses OK (E:07, H:D9, L:FF)

avrdude done.  Thank you.

Not sure why it won't read the flash and save it? It does say on the BangGood tester (for which the screen is on) Bat. 4.7V empty! Could that have anything to do with it, because it seems to read the chip Ok?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 09, 2015, 04:29:43 pm
You need to define the format (Intel Hex).

The corrected command is:
Code: [Select]
avrdude -c avrisp -p m328p -P COM5 -b 19200 -U flash:r:"TransistorTester.hex":i -U eeprom:r:"TransistorTester.eep":i
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 09, 2015, 07:20:16 pm
Hi Tom666,

No still no success...I think that the reading of the flash is locked, could that be?

I finally decided to flash with version 1.12K (latest) and all went well. When I try and read the new flashed firmware, still the same problem, can't read it?

Many thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 09, 2015, 11:20:26 pm
@madires
Hi,
I tried the trendy 1.18m on a Chinese clone with ST7565 graphic LCD. The device was delivered with a 1.11k version.
I had to modify config.h not to flip X and Y on LCD and got it to work... quite:
- probing of resistances, capacitors and transistors work
- there is nothing graphic on the display, except basic for C and R, but not for transistors
- after probing, seem to be a loop which restarts the whole cycle every 5 seconds or so
- self test requires short circuit but nothing happens when shorted
I flashed the .hex made on a RaspberryPi 2 with avrdude by SPI bus.
Is it definitely due to different hardware?
Thx
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 10, 2015, 10:03:27 pm
Well, the behaviour described in my previous post seems normal according to the documentation... 1.18m supports graphic displays but does not display graphics :-(

I then switched to the 1.12k version (GM_328 device). The self-test function doesn't work well: it does not recognize that the probes are shorted, and displays two resistors of 0.00 Ohms between pins 1, 2 and 3! By selecting selftest in the menu, it says "short probes!" as they are already shorted and waits half a minute (even if I press the start button) then starts testing. Values are significantly different than those of the 1.11k version (for example -67 -67 -67 instead of -4 -4 -4 for T2) ???

Switched back to 1.11k...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 11, 2015, 04:11:39 pm
I tried the trendy 1.18m on a Chinese clone with ST7565 graphic LCD. The device was delivered with a 1.11k version.
I had to modify config.h not to flip X and Y on LCD and got it to work... quite:
- probing of resistances, capacitors and transistors work
- there is nothing graphic on the display, except basic for C and R, but not for transistors
- after probing, seem to be a loop which restarts the whole cycle every 5 seconds or so
- self test requires short circuit but nothing happens when shorted
I flashed the .hex made on a RaspberryPi 2 with avrdude by SPI bus.
Is it definitely due to different hardware?

Yep, Trendy 1.18m doesn't support the fancy pinout yet (I've written about this a few posts ago). It's the first release supporting graphic displays and the fancy pinout will be added the next release or two. The short circuit method might fail because of an un-self-adjusted tester. You can trigger the menu also by two short key presses (please read the README file!).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 11, 2015, 06:44:23 pm
Hello Madires,
I always read manuals, and behaviour is the same when accessing selftest by the menu... I just missed your limitation a few posts ago, sorry. At the moment I've switched to the "k" version.
Today I tried to recompile the 1.12k from the trunk repository, same problem.  Then I tried the 1.12k version given by tom666 on the mikrocontroller.net site, and this one works perfectly well! I'm wondering from which sources this version has been generated, as the zip file contained only hex and eep. Can you help Tomas?
Thanks in advance :-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: amirtebyan on August 11, 2015, 06:48:19 pm
Hi

I want to use ST7920 lcd in serial mode.
but this two pics from tester doc says different thing.
my uC is atmega328p-au

(http://oi61.tinypic.com/359ac90.jpg)(http://oi60.tinypic.com/ohldkz.jpg)

how should i connect this lcd to atmega328?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 11, 2015, 08:06:48 pm
I want to use ST7920 lcd in serial mode.
but this two pics from tester doc says different thing.
my uC is atmega328p-au

how should i connect this lcd to atmega328?

The circuit diagram is the correct one. The RST pin is defined in config.h but not used currently AFAICS.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 12, 2015, 07:49:35 am
@Tom666
Hi Tomas,
Which sources/makefile do you use to generate your GM_328 1.12k version? I tried to use the rev508 of the Mikrocontroller.net repository with no success, whereas yours work perfectly (rev464, I'll try rev502 you posted recently). Thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 12, 2015, 12:53:19 pm
Hi,
I used a folder ".../trunk/mega328_GM328/".

The attached file contains a compiled version of the firmware for GM328 tester (v1.12k r508) and myself edited "Makefile". The functionality of the firmware is no tested.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 12, 2015, 01:58:19 pm
Strange, I tried to use the .hex in the /trunk directory and to recompile it with the makefile found in the same directory: in both cases bad functionning. I examined your makefile and saw that the main difference is that you comment the flag DWITH_UART: does only that explain the behaviour?
Anyway, I'll try both your .hex and your makefile and try to conclude.
Thanks Tomas
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 12, 2015, 11:13:08 pm
I tried the 1.12k_R508 version, with the .hex file compiled by Tom666 and one compiled by myself, with same results: bad functionning. The 1.12k_R464 .hex file provided by Tom666 is working perfectly.I didn't try the R502 version. My conclusion is that the source files of R508 have problems, at least for GM328. I'll try to alert Karl-Heinz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 13, 2015, 11:28:02 am
The answer from Karl-Heinz:

> An update with 1.12k version has been made possible only with the R464 revision

The newer Software additionally output a LCD-CE signal at pin PD5.
Unfortunally the GM328 has connected this signal to a grounded
ChipEnable (CE) input of the graphic controller. So the high signal of
the PD5 output is
shorted to GND. At the graphic board you should cut the useless
connection to pin 6 of the connector strip to prevent a shorted output.
Best regards,
Karl-Heinz

Good to know!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 13, 2015, 06:42:47 pm
Hi Karl,
I removed two pins on the LCD connector (3 and 6) and now the last
version of software works normally!
The pin 3 was also connected to ground, and as it is the cursor of the
contrast potentiometer (not working as it is a software function for
this display), when turned off completely it was generating also a short
circuit... Usual Chinese engineering.
Once more Vielen Dank :-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on August 13, 2015, 08:50:04 pm
...Usual Chineese engineering...
Oh please...
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 15, 2015, 03:49:52 pm
Interesting DIY kit of tester with G-LCD and operated with rotary encoder:
http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter/381351024208 (http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter/381351024208)
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

Case for this tester:
http://www.ebay.com/itm/Graphics-Version-Transistor-Tester-Case-Enclosure-Shell-Housing-Box-For-DIY-/231644539682 (http://www.ebay.com/itm/Graphics-Version-Transistor-Tester-Case-Enclosure-Shell-Housing-Box-For-DIY-/231644539682)
http://www.banggood.com/Supporting-Shell-For-DIY-M12864-Graphics-Version-Transistor-Tester-Kit-p-989949.html (http://www.banggood.com/Supporting-Shell-For-DIY-M12864-Graphics-Version-Transistor-Tester-Kit-p-989949.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: johnka on August 16, 2015, 11:29:22 pm
I found these boards on banggood and I'm thinking to buy one of these.
Which one should I prefer? 16x2 or 128x64 screen? Which one has the latest firmware and which one follows the original schematic with good quality components? Could I reflash the firmware by downloading the latest one from Karl-Heinz's repo? (I have a USBasp and an Arduino which could be used as ISP programmer.)
Also I'm thinking to make one myself. For start I could use a 16x2 LCD that I already have and a ATMEGA328. Do I need an external crystal oscillator? Some boards on ebay have one and some others don't. What fuses should I use on my microcontroller?
Title: Re: $20 LCR ESR Transistor checker project
Post by: newDIY on August 17, 2015, 04:35:03 am
I found these boards on banggood and I'm thinking to buy one of these.
Which one should I prefer? 16x2 or 128x64 screen? Which one has the latest firmware and which one follows the original schematic with good quality components? Could I reflash the firmware by downloading the latest one from Karl-Heinz's repo? (I have a USBasp and an Arduino which could be used as ISP programmer.)
Also I'm thinking to make one myself. For start I could use a 16x2 LCD that I already have and a ATMEGA328. Do I need an external crystal oscillator? Some boards on ebay have one and some others don't. What fuses should I use on my microcontroller?

I cannot answer your questions about the bangood board.  You would probably need to find someone who has that specific board to answer those detailed questions.

From what I have been reading, the external 8 MHZ crystal oscillator is needed. 

If you want to build a board, you can checkout the original Tester development site (in German) at: www.mikrocontroller.net/topic/248078 (http://www.mikrocontroller.net/topic/248078)  They have PCB board layouts and AVR code.  I would give you some links on that site, but google Chrome is not in the mood to translate German tonight.

There are also some PCB board designs in this EEVblog thread as well.

Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 17, 2015, 08:50:53 am
I found these boards on banggood and I'm thinking to buy one of these.
Which one should I prefer? 16x2 or 128x64 screen? Which one has the latest firmware and which one follows the original schematic with good quality components? Could I reflash the firmware by downloading the latest one from Karl-Heinz's repo?

The quality of the components is the same. In principle, no matter which device you buy, because the only difference is in the used type of LCD and control. Both devices are identical to the basic schematic diagram and can therefore use the official software from Mr. Karl-Heinz.

Also I'm thinking to make one myself. For start I could use a 16x2 LCD that I already have and a ATMEGA328. Do I need an external crystal oscillator? Some boards on ebay have one and some others don't. What fuses should I use on my microcontroller?

8MHz external crystal to a certain extent it contributes to a more accurate test results, but you omit it. MCU will clocked with internal 8 MHz RC oscillator - the difference is not critical. It is important to choose the most accurate values of resistors 680 and 470K (tolerance of 0.1%).

In the attached files you will find materials for tester in minimized form. Does not include auxiliary power circuit, external crystal and a source of reference voltage 2.5V. Features of this tester are preserved and are identical with the standard version. It is advisable to use firmware with blocked function "Auto Power Off" (DPO = Disable Power Off).

Setting fuses for ATmega328 and ATmega328p (int. RC 8MHz):
lfuse:0xe2 hfuse:0xd9 efuse:0x04 (0xfc)

Note:
The materials can be downloaded as well from this discussion forum (svetelektro.com):
http://svetelektro.com/modules.php?name=Forums&file=viewtopic&f=18&t=30285&p=548740#p548740 (http://svetelektro.com/modules.php?name=Forums&file=viewtopic&f=18&t=30285&p=548740#p548740)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 17, 2015, 03:13:54 pm
Hello all, I received this tester yesterday and so far I'm happy with it for $22 prime Amazon.
http://www.amazon.com/gp/product/B00OOQC2E8?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00#Ask (http://www.amazon.com/gp/product/B00OOQC2E8?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00#Ask)

It came preloaded with 1.12 and all the features work, the signal generator, PWM, and frequency counter was a bonus that I didn't expect. It's running the 328 chip and has the 8 MHz crystal also with a nice display. But it's missing the SPI for updating it, the good he's is I can remove the chip.

I have a friend coming to visit in October who ordered a different one from eBay, I need to look at the internals but I think it might be able to do more then it does now if I update it.
Then I realized I've never got into the programming part of these chips, I'm planning on using AVRDude and figured it's time to buy a programer now with this running the 328, my LED flashlights I build using the amtel tiny, and my 3D printers using the 1280/2560 chips. It would only be needed for the printers if I brick one to recover the boot loader. I'm also testing soldering station that are using the 328 chip and found some bug, they fixed it but now I have to wait on the slow boat from China for the new chip. If I had a programer they could have just emailed me the code to compile and I would have been back to testing again.

So my question is what would be a recommended programer that can do these style of chips? I'm trying to keep the price down on a budget and currently don't have a need to program PIC chips, just the different variety of amtel chips.
I see a lot of different kinds on Amazon, I try to stay off of eBay, just a preference. The only one I confirmed to do all these chips so far is about $70, but even if I get two $10 programmers because I know the 1280/2560 chips might need a programer just for that class I would rather do that for $20 and maybe a interface board for easy plug and program, then unplug.

Any suggestions are welcomed, thank you.

Oh, and after reading a few pages of this it looks like theirs is a 1.18 now so I guess I don't have the latest. Anything worth updating for fro the 1.12 to the 1.18?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 17, 2015, 04:25:56 pm
So my question is what would be a recommended programer that can do these style of chips? I'm trying to keep the price down on a budget and currently don't have a need to program PIC chips, just the different variety of amtel chips.
I see a lot of different kinds on Amazon, I try to stay off of eBay, just a preference. The only one I confirmed to do all these chips so far is about $70, but even if I get two $10 programmers because I know the 1280/2560 chips might need a programer just for that class I would rather do that for $20 and maybe a interface board for easy plug and program, then unplug.

The Diamex ALL-AVR (about 30 Euros) supports SPI, PDI and TWI. For SPI you could also use an Arduino or a BusPirate. All three work fine with avrdude.

Oh, and after reading a few pages of this it looks like theirs is a 1.18 now so I guess I don't have the latest. Anything worth updating for fro the 1.12 to the 1.18?

There are two firmwares (besides some Chinese mods). The commonly used one is the k-firmware by Karl-Heinz (1.12k) and there's also the m-firmware (1.18m) comming in two flavours (classic for character displays, trendy for character and graphic displays). You can get both firmwares at http://www.mikrocontroller.net/svnbrowser/transistortester/ (http://www.mikrocontroller.net/svnbrowser/transistortester/) and the README file in the m-firmware's archive explains the differences between both.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 17, 2015, 08:45:04 pm
Thanks madires, but the shipping may be a deal breaker. It looks like a nice unit, but also looks like it's mainly sold in Germany and my German is rusty. I haven't spoke it since high school.
I think I need to give the one back I bought, and get the EZM Electronic one from page 63 since it looks like the closest Chinese made one to the intended specs and had the SPI pin wholes ready to flash.
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/930/
Is this the closest to actual specs for what the software was intended to operate? Or is their another I have not seen yet?

The yellow one from LCR-T4 also being made by SainSmart looks like it's also following close to specs, but he one I have now is a EZM and it's clean, good solder joints and no mess. That just means I have to get it from eBay.

I've attached a  the picture of the one I bought fromEZM and it works great, looks nice on the display and all but 5 frequencies work on my RIGOL SD1054Z. The only problem is that even it I buy your recommended programer if it was available to ship to me in English I would still need another board to plug the chip into. I would hate to return something that works, so maybe I'll keep it as a backup.

Does anyone know what this trip pot is installed for on the one in the picture? It's under the bottom left corner of the LCD. Maybe it was for contrast before the setting was moved to a software adjustable?
But it doesn't seem to effect anything, the PWM, square wave signal, transistor meter, frequency counter and all are not effected by me changing this pot?????
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 18, 2015, 12:02:29 am
Hello everyone,

I have the yellow tester that Tom666 mentionned in an earlier post (T3_T4 ST 7565 tester). When I go into the function menu and select Frequency, it shows me Frequency f = 0HZ, and a second later a blank screen. It seems to be locked on the blank screen because whatever I do (press the button short press, long press, etc.) nothing happens. I have to disconnect the battery to be able to restart the tester.

I am running version 1.12k release 508.

Is there something wrong with the function Frequency or is it just my tester?

Many thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 18, 2015, 05:16:07 am
@rddube
For the pot read my last message a few posts above.
Title: Re: $20 LCR ESR Transistor checker project
Post by: wasyoungonce on August 18, 2015, 07:50:32 am
Thanks madires,.......................I've attached a  the picture of the one I bought fromEZM and it works great,........................

This is the one I have....no programming port....Sigh! I missed that.  Mine does not have the pot.  Just putting mine in a case now.   Guess I'll have to parallel program update it using my TL866 but I think I need an external crystal and are a little unsure.  Think my firmware is 1.11 or 1.12...sorry don't know as I've removed the LCD to lower it and the ZIF socket atm.  I'll post back when done in the case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 18, 2015, 09:38:03 am
I have the yellow tester that Tom666 mentionned in an earlier post (T3_T4 ST 7565 tester). When I go into the function menu and select Frequency, it shows me Frequency f = 0HZ, and a second later a blank screen. It seems to be locked on the blank screen because whatever I do (press the button short press, long press, etc.) nothing happens. I have to disconnect the battery to be able to restart the tester.

I am running version 1.12k release 508.

Is there something wrong with the function Frequency or is it just my tester?

Seems to be the frequency counter which requires a small hardware add-on. The square wave generator is "f-Generator".
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 18, 2015, 02:24:31 pm
I tested the current revision 508 (v1.12k) on my LCR-T3 tester and everything works normally even without the add-on frequency measurement. For the power supply I use the 9V battery.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amirtebyan on August 18, 2015, 07:19:10 pm
hi

does atmega2560 version support all feature like atmega328 version?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 18, 2015, 08:09:02 pm
@rddube
For the pot read my last message a few posts above.
Odd, mine may still have the pod on the board. But I read your previous posts and the pic I put up was from a sales page. If I take a picture of my actual one I received pin 6 is not soldered to the display, it's a dead link. In fact I took a jumper wore and put it in pin six and it acted as an antenna for the frequency counter. I think the counter only read up to 1 or 2Mhz so the only thing I had to test it with was my house. It picked up the electrical field at 60Hrz and I knew it worked. My scope will to the same sometimes when my probe is not properly grounded.

I need to check pin three also to make sure they didn't wire that one, thanks,
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 18, 2015, 08:12:23 pm
Thanks madires,.......................I've attached a  the picture of the one I bought fromEZM and it works great,........................

This is the one I have....no programming port....Sigh! I missed that.  Mine does not have the pot.  Just putting mine in a case now.   Guess I'll have to parallel program update it using my TL866 but I think I need an external crystal and are a little unsure.  Think my firmware is 1.11 or 1.12...sorry don't know as I've removed the LCD to lower it and the ZIF socket atm.  I'll post back when done in the case.

Mine is also missing the programming pins, but my local electronics place had UNO on sale for $5, so I grabbed one, I'll remove the chip and add a ZIF socket and just use the UNO board to program it for now. I think it will work, I've never messed with uno avr before, but sound logical.
If not, I will still get to tinker and learn :-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 18, 2015, 08:14:39 pm
hi

does atmega2560 version support all feature like atmega328 version?

According to the 106 page off I read a few nights ago, the answer is yes. The reason is the 2560 has enough room for the extra code to support the other features unlike the smaller chips.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 19, 2015, 12:49:20 am
@Gixy

No, my display is working fine for everything on the transistor tester...only the function menu Frequency blanks after a second or 2 into the menu and then the tt is frozen...only way to get it back to work is to unplug battery.

When I unplug battery and start the tt, it works just fine. Can't get the function Frequency to work however.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 19, 2015, 07:23:50 am
Mine is also missing the programming pins, but my local electronics place had UNO on sale for $5, so I grabbed one, I'll remove the chip and add a ZIF socket and just use the UNO board to program it for now. I think it will work, I've never messed with uno avr before, but sound logical.
If not, I will still get to tinker and learn :-)

It will not work!
The only option is to use the Arduino as an AVR ISP programmer. But you'll need some an AVR ISP adapter, which will be used to interconnect the Arduino and the AVR MCU.

The necessary information you will find here:
https://www.arduino.cc/en/Tutorial/ArduinoISP (https://www.arduino.cc/en/Tutorial/ArduinoISP)

Instead a breadboard you can use this development kit:
http://www.ebay.com/itm/ATmega8-ATmega48-Development-Board-AVR-Board-Parts-and-Components-DIY-New-Kit-/391132515152 (http://www.ebay.com/itm/ATmega8-ATmega48-Development-Board-AVR-Board-Parts-and-Components-DIY-New-Kit-/391132515152)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 19, 2015, 08:18:06 am
No, my display is working fine for everything on the transistor tester...only the function menu Frequency blanks after a second or 2 into the menu and then the tt is frozen...only way to get it back to work is to unplug battery.
When I unplug battery and start the tt, it works just fine. Can't get the function Frequency to work however.

As I wrote above (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg734194/#msg734194), everything works normally.

The attached file contains the software that I tested:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 19, 2015, 08:30:38 am
Mine is also missing the programming pins, but my local electronics place had UNO on sale for $5, so I grabbed one, I'll remove the chip and add a ZIF socket and just use the UNO board to program it for now. I think it will work, I've never messed with uno avr before, but sound logical.
If not, I will still get to tinker and learn :-)

It will not work!
The only option is to use the Arduino as an AVR ISP programmer. But you'll need some an AVR ISP adapter, which will be used to interconnect the Arduino and the AVR MCU.

The necessary information you will find here:
https://www.arduino.cc/en/Tutorial/ArduinoISP (https://www.arduino.cc/en/Tutorial/ArduinoISP)

Instead a breadboard you can use this development kit:
http://www.ebay.com/itm/ATmega8-ATmega48-Development-Board-AVR-Board-Parts-and-Components-DIY-New-Kit-/391132515152 (http://www.ebay.com/itm/ATmega8-ATmega48-Development-Board-AVR-Board-Parts-and-Components-DIY-New-Kit-/391132515152)

Sorry Tom,  I should have been a little more clear in that. I was going to put the ZIF socket on the bread board and use the uno I bought to program it, so the uno would be the ISP using IDE. Like in your breadboard picture. Then I also found out I could have bought 2 UNO's to make it even easier and no bread boarding, but that takes away some of the fun.

But since then I've been doing a lot of reading and would really like the option to to bootloader also without buying an expensive MK II or other type. I have a raspberry pi and found that you can use AVRDude on pi with the gpio pins out to the breadboard. This sound like a better option since I think AVRDude on Pi will let me do just about any avr chip. Some of the cheaper programmers like the tiny can not program the mega chips like the 2560, were I think the Pi programming will not have that limitation.

No I just need to confirm what Pi to use. I have a B and the new one with the quad core and more memory. But everyone I've seen do it so far is using the older Pi and I have to wonder if their is a reason for this.
I'm leaning to get the Pi to be my all in one programer and after confirming a few things on the breadboard, then move it to a permanent PCB with a switch and a few voltage regulators to switch between 3.3V and 5V in case I ever start using any 3.3V projects also. I just want to make the solution the most robust to cover the most I can with a single setup.
Maybe the only downfall of the AVRDude Pi solution would be not able to read the debug, but I'm sure I can figure something out for that also?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 19, 2015, 09:05:42 am
@Scottjd

OK, but It would be better and cheaper solution by buying the USBasp (http://www.ebay.com/itm/USBASP-USBISP-AVR-Programmer-Adapter-10-Pin-Cable-USB-ATMEGA8-ATMEGA128-Arduino-/310506909410) and this AVR ISP adapter (http://www.ebay.com/itm/ATmega8-ATmega48-Development-Board-AVR-Board-Parts-and-Components-DIY-New-Kit-/391132515152) - total price is US$1.87 + US$1.87. The USBasp programmer can also program the ATmega2560 (see. the list of the supported MCUs).

Supported processors by programmer USBasp:

Mega Series
ATmega8      ATmega8A   ATmega48   ATmega48A   ATmega48P
ATmega48PA   ATmega88   ATmega88A   ATmega88P   ATmega88PA
ATmega168   ATmega168A   ATmega168P   ATmega168PA   ATmega328
ATmega328P   ATmega103   ATmega128   ATmega128P   ATmega1280
ATmega1281   ATmega16   ATmega16A   ATmega161   ATmega162
ATmega163   ATmega164   ATmega164A   ATmega164P   ATmega164PA
ATmega169   ATmega169A   ATmega169P   ATmega169PA   ATmega2560
ATmega2561   ATmega32   ATmega32A   ATmega324   ATmega324A
ATmega324P   ATmega324PA   ATmega329   ATmega329A   ATmega329P
ATmega329PA   ATmega3290   ATmega3290A   ATmega3290P   ATmega64
ATmega64A   ATmega640   ATmega644   ATmega644A   ATmega644P
ATmega644PA   ATmega649   ATmega649A   ATmega649P   ATmega6490
ATmega6490A   ATmega6490P   ATmega8515   ATmega8535   

Tiny Series
ATtiny12   ATtiny13   ATtiny13A   ATtiny15   ATtiny25
ATtiny26   ATtiny45   ATtiny85   ATtiny2313   ATtiny2313A

Classic Series
AT90S1200   AT90S2313   AT90S2333   AT90S2343   AT90S4414
AT90S4433   AT90S4434   AT90S8515
AT90S8535         

CAN Series
AT90CAN128         

PWM Series
AT90PWM2   AT90PWM3
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 19, 2015, 10:37:24 am
@scottjd
If you have a Pi (any one), you can program your Atmega. There are a lot of tutorials to do that, one of them is https://projects.drogon.net/raspberry-pi/gertboard/ It uses the Gertboard but you can use a breadbord with the minimum required components. It also uses a modified version of avrdude which allows to use gpio pins. Works very well here.
@Tom666
As I wrote earlier, GM328 is working with 1.12k rev508 only if you remove the short to ground of pin 3 of the display board. You should also verify that the cursor of the pot is not linked to ground by pin 6 of display board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 19, 2015, 11:53:30 am
@Gixy

So, if I understand it well :), rddube mentioned in his last posts problem with the LCR-T4 tester (not with the variant GM328).

Apparently there arose a problem in communication :-//

... I have the yellow tester that Tom666 mentionned in an earlier post (T3_T4 ST 7565 tester). When I go into the function menu and select Frequency, it shows me Frequency f = 0HZ, and a second later a blank screen. It seems to be locked on the blank screen because whatever I do (press the button short press, long press, etc.) nothing happens. I have to disconnect the battery to be able to restart the tester.
I am running version 1.12k release 508.
Is there something wrong with the function Frequency or is it just my tester? ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 19, 2015, 01:32:04 pm
@Scottjd

OK, but It would be better and cheaper solution by buying the USBasp (http://www.ebay.com/itm/USBASP-USBISP-AVR-Programmer-Adapter-10-Pin-Cable-USB-ATMEGA8-ATMEGA128-Arduino-/310506909410) and this AVR ISP adapter (http://www.ebay.com/itm/ATmega8-ATmega48-Development-Board-AVR-Board-Parts-and-Components-DIY-New-Kit-/391132515152) - total price is US$1.87 + US$1.87. The USBasp programmer can also program the ATmega2560 (see. the list of the supported MCUs).

Supported processors by programmer USBasp:

Mega Series
ATmega8      ATmega8A   ATmega48   ATmega48A   ATmega48P
ATmega48PA   ATmega88   ATmega88A   ATmega88P   ATmega88PA
ATmega168   ATmega168A   ATmega168P   ATmega168PA   ATmega328
ATmega328P   ATmega103   ATmega128   ATmega128P   ATmega1280
ATmega1281   ATmega16   ATmega16A   ATmega161   ATmega162
ATmega163   ATmega164   ATmega164A   ATmega164P   ATmega164PA
ATmega169   ATmega169A   ATmega169P   ATmega169PA   ATmega2560
ATmega2561   ATmega32   ATmega32A   ATmega324   ATmega324A
ATmega324P   ATmega324PA   ATmega329   ATmega329A   ATmega329P
ATmega329PA   ATmega3290   ATmega3290A   ATmega3290P   ATmega64
ATmega64A   ATmega640   ATmega644   ATmega644A   ATmega644P
ATmega644PA   ATmega649   ATmega649A   ATmega649P   ATmega6490
ATmega6490A   ATmega6490P   ATmega8515   ATmega8535   

Tiny Series
ATtiny12   ATtiny13   ATtiny13A   ATtiny15   ATtiny25
ATtiny26   ATtiny45   ATtiny85   ATtiny2313   ATtiny2313A

Classic Series
AT90S1200   AT90S2313   AT90S2333   AT90S2343   AT90S4414
AT90S4433   AT90S4434   AT90S8515
AT90S8535         

CAN Series
AT90CAN128         

PWM Series
AT90PWM2   AT90PWM3

Ho Tom, thanks. I already have the AVR breakout board or all the parts for it. The only difference for the schematics I've seen is it runs a 16Mhz  oscillator Crystal, not an 8 that the lot provided.
I also managed to get a couple authentic ftdi chip programmers that were on clearance for $5 that will do either 3.3V or 5V. So I'm sure at this point I can flash the chip.
But the reason I'm looking at using the Pi is because I believe I would be able to flash the boot loader also on blank chips. That may be the only difference with the writer you recommended not being able to write the bootloader?

I deal a lot with 3D printers and you would be amazed on how many people flash it with the wrong hex and overwrite the bootloader.
So I think the Pi and modded avrdude 6.1 or higher will give me this option to help people fix their boards that run the 1280 or 2560.

I have both pi's the model Band the new version 2 with the quad A7 processor and more memory.
So I'm just trying to worn out the details, I can't find anyone that had done it with the new Pi yet? But I would rather use the new one for obvious reasons to compile and make faster.
I guess I'll start with the new one, if it does not work then go back to the model B that other have used.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 19, 2015, 01:50:07 pm
@scottjd
If you have a Pi (any one), you can program your Atmega. There are a lot of tutorials to do that, one of them is https://projects.drogon.net/raspberry-pi/gertboard/ It uses the Gertboard but you can use a breadbord with the minimum required components. It also uses a modified version of avrdude which allows to use gpio pins. Works very well here.
@Gixy
Thanks, I've been reading up on the Pi as an avr programer all night. Just trying to decide what Pi to use, the Model B or the new Pi2 I got a couple months ago. I've never booted it yet so I may use the Pi2.
If you run the Pi can you confirm that you can also write bootloaders on blank or bad flashed chips. I know the bad flash ones will need the switch for erase chip first in the AVRDude syntax line before writing the new bootloader if it's possible from a Pi?

FYI: I also confirmed the one I received does not have pin 3 and pin 6 connected. They cut the trace and still left the potentiometer on the board. I guess I'll unsolder it and use it for another project..

Thanks,
Scott
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 19, 2015, 02:50:34 pm
... But the reason I'm looking at using the Pi is because I believe I would be able to flash the boot loader also on blank chips. That may be the only difference with the writer you recommended not being able to write the bootloader? ...

It is a very simple operation (writing the bootloader) with the USBasp.
For example, through the Arduino IDE:
http://tutorial.cytron.com.my/2011/12/19/burning-arduino-bootloader-with-avr-usbasp/ (http://tutorial.cytron.com.my/2011/12/19/burning-arduino-bootloader-with-avr-usbasp/)

... I deal a lot with 3D printers and you would be amazed on how many people flash it with the wrong hex and overwrite the bootloader.
So I think the Pi and modded avrdude 6.1 or higher will give me this option to help people fix their boards that run the 1280 or 2560. ...

Rewriting bootloader would not be possible, if are properly writen the lock bits of the MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gixy on August 19, 2015, 05:20:06 pm
Hi Scott,
I also have both Pis : model B and Pi2. They can write .hex files in Atmega, with or without bootloader. The 'gpio' programmer makes bit-banging on 4 serial lines, simply flashing an .hex file. You can afterwards use the bootloader with an ordinary serial interface, but with little or no interest as you're obliged to have the previous programmer to flash the bootloader the first time.
If the lock bits are set, only 'parallel' programmers can reset the device. In all other cases you can re-flash the fuses.
Out of factory the Atmega are configured with internal RC oscillator. You can then put the device on a breadboard without any crystal circuit. If you then configure the fuses to crystal oscillator, further programming will require the crystal on the breadboard (or on the target board if you're using ISP).
Denis
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 19, 2015, 08:27:18 pm
@Tom
I couldn't look at the link about bootloader with IDE, the site reached max bandwidth.
But if I had to guess this is about using IDE to restore a bootloader if you over wrote with AVRDude.
From what I understand, this could take hours to do?

I'm not sure if Makerbot writes the proper locks on the MCU, I do know someone else that does it with a smart programer so I believe it might be possible. I have a board that has a bad fet on the 3.3V rail so it like to make magic smoke with the stepper controllers. But everything else works, so I was going to pull the locks and stuff once I got the Pi set up with AVRDude, then I would know more.

@Denis
For some reason I got the impression that using the Pi would be more like using a smart programer without having to spend the $60, but if it's just using the SPI to bit bang then it's basically the same as using the FTDI chip USB to serial interface programmers I have.

I think the guy I know that currently fixes Makerbot boards will put a new 1280/2560 chip on the board so I'm assuming it's a blank unlocked chip. He uses a smart programer like the one from digikey or mouser. I just got a reword SMD statin n and have been practicing on mounting these chips and doing removals so I guess that was my thought in direction and didn't want to spend another $60-$80 on a smart programer.

But if a parallel programer is needed then I'm out of luck, I have a USB to serial 9 pin for the Mac, and Windows 10 Asus tablet I use for my microscope, and the Pi's running another flavor of Debian. I haven't decided on what I'm going to set up the new Pi2 with yet.but no more parallel machines, I may have a pic card, but I don't have a full desktop to lug it into anyway.

So if Pi is just doing bitbang then what is the advantage of using it if any over just running IDE on my MacBook Pro Retina?
Even with bitbang wouldn't I be able to put a bootloader in a completely unlocked blank chip and then set the fuses and locks at the end? Or will that still need a smart programer?

I was going to sell my 22" Samsung 1080P monitor, had it lacked in the box and all but decided to break it out just for the Pi2 and rearranged my whole work bend to accomadate for this screen. After I realized I probably could have just found the IP on my Cisco ASA that is handling my DHCP calls and used the win10 tablet to ssh into it with putty. But sleep is unknown in the last 48, long story why. Let's just say bad side effects from a blood infusion last week is keeping me awake so I've done a lot of reading. In fact, I never touched a FTDI programer or arduino until yesterday and everything I know is from the last 24 hours.

I also noticed that IDE on the Mac is using AVRDude in the background for the programming, so IDE is just a sketch editor, compiler and AVRDude does the flashing?

So what is the advantage (if any) of running the full raw AVRDude over using IDE besides being able to use some switches like -F for ignoring the signature of a chip? And even that could be fixed in the conf file.

Currently I know you can use one arduino to act as an AVR with IDE also, and I bought 3. I have the mini pro and for programming it needs the FTDI interface. I have the Uno R3, and the Mega R3. So between them all if I was to wipe a chip I could recover it from another with the correct jumper pins between  two of them. My local electronics place was having a sale, I think it cost me $4 for mini pro, $5 for the UNO, $10 for the MEGA, and $5 for the FTDI programer. $24 US for all. They also had spark fun UNO kits build your own that need the programer as well but they were marked down to $5 and it included the 328 chip. I figured it would be fun to build two of them and give them away and use the third for parts since it had everything I needed to breadboard for the Pi interface, then after I confirm it worked I was going to solder it all in place with a ZIF DIP 28 pin I already own also for easy chip flashing.

Sorry if I side tracked the thread a little, this is mostl likely my last questions and I need to try to get some sleep. So I guess when I figure out what the advantage using the Pi, if any, then I can decide if I will move forward with the Pi as a programer or just bread board something to use one of the others as a AVR programer using IDE. Is using Pi any faster then using a FTDI interface basic board?

I was also looking at the atiny adafruit smart programer but it has limit like not being able to flash the 1280/2560 chips. How much faster is the smart programmers, are they worth the money, or the $20 to build one from adafruit?

My apologies if I got any if the terminology incorrect up front, as I mentioned I've only studied these randomly in my free time over the last 38 hours or so. I lost could how long I've been awake.
Also thanks for the information and explanations, you guys have managed to answer some questions I was not able to get or understand after reading many, many tutorials and watching YouTube videos. I guess most tutorial explain the basics, but I'm looking for a deeper understanding before I decide on how I want to build my flash hex setup. I also eventually would like to use this setup for probing things like2 old linksys WRT54G routers and see if I can extract the firmware from the eeprom or controller chip being used. This would be for learning reasons only for now but eventually will be put to use for other Linux embedded running devices.

Thanks,
Scott
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 20, 2015, 08:49:56 am
... But if I had to guess this is about using IDE to restore a bootloader if you over wrote with AVRDude.
From what I understand, this could take hours to do?

I'm not sure if Makerbot writes the proper locks on the MCU, I do know someone else that does it with a smart programer so I believe it might be possible. ...

... For some reason I got the impression that using the Pi would be more like using a smart programer without having to spend the $60 ...
... I guess that was my thought in direction and didn't want to spend another $60-$80 on a smart programer ...
... But if a parallel programer is needed then I'm out of luck ...
... Or will that still need a smart programer? ...
... How much faster is the smart programmers, are they worth the money, or the $20 to build one from adafruit? ...

@Scott
There is no reason to use the expensive equipments. Burning the bootloader is a matter of a few seconds.

For successful writing bootloader you must perform the following essential steps:

1. Unlock bootloader section
2. Set fuses
3. Erase
4. Program bootloader into microcontroller
5. Lock the bootloader section so that it cannot be erased

For example, you can use from the command line directly the AVRDude.

Burn Arduino Mega 2560 bootloader with the USBasp (http://www.fischl.de/usbasp/)

first step - unlock fuses, erase, verify:
avrdude -c usbasp -p m2560 -B 0.5 -U lock:w:0x3F:m -U efuse:w:0xFD:m -U hfuse:w:0xD8:m -U lfuse:w:0xFF:m -e -v

the second step - write the bootloader, set the lock fuse, verify:
avrdude -c usbasp -p m2560 -B 0.5 -U flash:"stk500boot_v2_mega2560.hex":a -U lock:w:0x0f:m -v

It's all ;)

FYI:
There are two "major" groups of memory protection bits:
- The Memory Protection Lock Bits refer to two bits, LB2 and LB1.
- The Bootloader Lock Bits refer to four bits: BLB12, BLB11, BLB02, and BLB01.

The Memory Protection Lock Bits define what you're allowed to do using external programming hardware such as ISP or HVPP.
If LB1 is programmed, then you can no longer add new data the existing content in Flash or EEPROM using an external programmer.
If LB2 is programmed, then you can no longer read back existing Flash or EEPROM content using an external programmer.
The combination (LB1 = unprogrammed, LB2 = programmed) is invalid.
You can use an external programmer to totally erase everything (Flash, EEPROM... everything) in one fell swoop. In that case, you will be free to re-program the chip again with no restrictions.

The Bootloader Lock Bits are further subdivided into two "minor" groups:
- BLB02 and BLB01: the "Application section" bootloader protection.
If BLB01 is programmed, then the bootloader cannot use the SPM instruction to write new data in the Application section of Flash.
If BLB02 is programmed, then the application cannot use the LPM instruction. (And therefore constant data tables, initializers, etc will be broken in C.)
- BLB12 and BLB11: the "Bootloader section" bootloader protection.
If BLB11 is programmed, then the bootloader cannot use the SPM instruction to overwrite itself.
If BLB12 is programmed, then the bootloader cannot use the LPM instruction. (And therefore it will be impossible to verify the success of subsequent bootloader upgrades.)

Best regards
Tomas
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 20, 2015, 12:14:29 pm
I also noticed that IDE on the Mac is using AVRDude in the background for the programming, so IDE is just a sketch editor, compiler and AVRDude does the flashing?

So what is the advantage (if any) of running the full raw AVRDude over using IDE besides being able to use some switches like -F for ignoring the signature of a chip? And even that could be fixed in the conf file.

Yep, avrdude is the common tool to program AVR's fuses, flash and EEPROM. It doesn't matter if you run it directly in a shell or via the IDE. I prefer a simple "make upload" to program flash and EEPROM , or "make fuses" to set the fuse bits. Someone else might prefer a fancy GUI. Another useful option for avrdude is "-B <bitclock>" in case you have to deal with a clock problem. I don't know if most IDEs support that option.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 20, 2015, 07:12:50 pm
No, my display is working fine for everything on the transistor tester...only the function menu Frequency blanks after a second or 2 into the menu and then the tt is frozen...only way to get it back to work is to unplug battery.
When I unplug battery and start the tt, it works just fine. Can't get the function Frequency to work however.

As I wrote above (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg734194/#msg734194), everything works normally.

The attached file contains the software that I tested:

Thank you Tom..I'll give it a try and let you know if all is fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 21, 2015, 01:47:28 am
No, my display is working fine for everything on the transistor tester...only the function menu Frequency blanks after a second or 2 into the menu and then the tt is frozen...only way to get it back to work is to unplug battery.
When I unplug battery and start the tt, it works just fine. Can't get the function Frequency to work however.

As I wrote above (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg734194/#msg734194), everything works normally.

The attached file contains the software that I tested:

Thank you Tom..I'll give it a try and let you know if all is fine.

Well Tom666 is my savior again! It works just fine with your version. I looked at my version which I compiled with a recent version of GCC as you recommended in one of your previous posts, used the makefile in the directory and I get a hex file which is a few bytes  less than you:

Your hex file: 81 222 bytes
My hex file :  81 210 bytes

Both eep files are 56 bytes. My version of avr-gcc is 4.8.1

So I wonder why I don't compile to the same file size as yours and why some functions (like frequency) don't work properly?

Many thanks again Mr. Tom!
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 21, 2015, 09:20:15 am
... My version of avr-gcc is 4.8.1
So I wonder why I don't compile to the same file size as yours and why some functions (like frequency) don't work properly? ...

Try my updated WinAVR-20100110 (http://expirebox.com/download/08d5ff687d07aa7139234319bb90f584.html) - link expires after 48 hours.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 21, 2015, 12:34:28 pm
Both eep files are 56 bytes. My version of avr-gcc is 4.8.1

So I wonder why I don't compile to the same file size as yours and why some functions (like frequency) don't work properly?

The developers of the avr-gcc are improving the optimizations. Usually, a current version generates smaller code than an older version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 21, 2015, 01:32:29 pm
The problem is somewhere else, because my updated version of the WinAVR-20100110 is also used the AVR-GCC v4.8.1.

rddube has a probably a some bug in his version 4.8.1 and then the result of the compilation is a error in the final hex file (problem with the function of the frequency measurement).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 22, 2015, 08:48:26 am
Hi Scott,
I also have both Pis : model B and Pi2. They can write .hex files in Atmega, with or without bootloader. The 'gpio' programmer makes bit-banging on 4 serial lines, simply flashing an .hex file. You can afterwards use the bootloader with an ordinary serial interface, but with little or no interest as you're obliged to have the previous programmer to flash the bootloader the first time.
If the lock bits are set, only 'parallel' programmers can reset the device. In all other cases you can re-flash the fuses.
Out of factory the Atmega are configured with internal RC oscillator. You can then put the device on a breadboard without any crystal circuit. If you then configure the fuses to crystal oscillator, further programming will require the crystal on the breadboard (or on the target board if you're using ISP).
Denis

@Tom and @Denis

Guys,
      I was finally able to sit down today and set up my new Pi2, I also bought a "build you own" UNO kit that was clearance at the local electronics store for $3. I bought it because I thought it would be fun to solder together and also it didn't have a programming FTDI or any programming chip on it. So I thought it would be a good test platform to try using Pi AVRDude with.
All went well, I have not programmed anything yet, but I was able to read the AVR and current locks.
Next I want to breadboard it, then use the dev PCB I found and set it up so I can change chips from the 328/128 to AtTiny chips with a couple of changes to some jumpers and use a ZIF DIP socket to be a little easier. I wanted to thank you for your input and help.
Now I just need to figure out what commands to use to make a backup hex file of a chip, assuming it may need some lock bits changed first, then backed up.

Oh, and now I can pull my component tester 328 and plug it into this uno board and flash it with the v1.18.
My friend got his today also, it's a SMD 328P, but his also has a 10 pin program header on the board. His firmware won't even let him bring up a menu to see what version it's currently running. So I think I will update his also after I check pins 6 and the other for contrast to the display to make sure it won't short out. If it's wired we may cut the traces and then update the firmware, but I need to get a closer look at it first to be sure.

Thanks again for the help guys,
Scott
Title: Re: $20 LCR ESR Transistor checker project
Post by: Scottjd on August 22, 2015, 09:00:59 am
I also noticed that IDE on the Mac is using AVRDude in the background for the programming, so IDE is just a sketch editor, compiler and AVRDude does the flashing?

So what is the advantage (if any) of running the full raw AVRDude over using IDE besides being able to use some switches like -F for ignoring the signature of a chip? And even that could be fixed in the conf file.

Yep, avrdude is the common tool to program AVR's fuses, flash and EEPROM. It doesn't matter if you run it directly in a shell or via the IDE. I prefer a simple "make upload" to program flash and EEPROM , or "make fuses" to set the fuse bits. Someone else might prefer a fancy GUI. Another useful option for avrdude is "-B <bitclock>" in case you have to deal with a clock problem. I don't know if most IDEs support that option.

I usually prefer command line VS GUI. I find you can do more with command line. Both the UNO's I bought to play with. One is a R3 with a onboard programming chip, and one was a self build kit without a program chip that I figured would be a good test for AVRDude, and it was. But for some reason both of them look to have authentic mega328p chips, but I get a signature not match error if I try to update the bootloader with the IDE. Trying to dig around the MAC app to figure out were I could a the -F switch was painful. It's was much easier to just add it to the command line from the Pi and run again, and all works now.
Scott
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 22, 2015, 10:52:55 am
... My version of avr-gcc is 4.8.1
So I wonder why I don't compile to the same file size as yours and why some functions (like frequency) don't work properly? ...

Try my updated WinAVR-20100110 (http://expirebox.com/download/08d5ff687d07aa7139234319bb90f584.html) - link expires after 48 hours.

Eureka Tom! I get exactly the same result as you, so it is probably something wrong with my version of WinAVR-20100110. My hex file is now 81 222 bytes, just like yours!

What is confusing, is that the already compiled version of the hex file in the directory mega328_t3_t4_St7564 (compiled by Karl Heinz I think?) for release 508 is 81 304 bytes ??

Looks now like there is a 510 revision out.....

Thank you again Tom!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on August 22, 2015, 10:55:01 am
Where can one find the changelog for the different revisions of version 1.12k (508, 509 and now 510) ?

Does anyone know?

Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on August 22, 2015, 11:30:17 am
Where can one find the changelog for the different revisions of version 1.12k (508, 509 and now 510) ?

Not sure of changelog, but if you know how subversion work, you'd know that the revisionnumber are an global number for the whole three, so if they, as in revision 509 only modifies documentation, you have an increase there, does not mean that there are code changes.

Here you see what have changed in the three for the varios commits:
https://www.mikrocontroller.net/svnbrowser/transistortester?view=revision&revision=508 (https://www.mikrocontroller.net/svnbrowser/transistortester?view=revision&revision=508)
https://www.mikrocontroller.net/svnbrowser/transistortester?view=revision&revision=509 (https://www.mikrocontroller.net/svnbrowser/transistortester?view=revision&revision=509)
https://www.mikrocontroller.net/svnbrowser/transistortester?view=revision&revision=510 (https://www.mikrocontroller.net/svnbrowser/transistortester?view=revision&revision=510)

In 510, there are some changes in config.c and lcd-routines.c (click the link "text-changed" to see what it is), and the rest is changes to documentation.

Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 22, 2015, 04:41:32 pm
... What is confusing, is that the already compiled version of the hex file in the directory mega328_t3_t4_St7564 (compiled by Karl Heinz I think?) for release 508 is 81 304 bytes ?? ,,,

The difference in the size of the final hex file is due to the fact that Karl-Heinz compiles (he works under Linux) with the AVR-GCC 4.8.2.

Where can one find the changelog for the different revisions of version 1.12k (508, 509 and now 510) ? ...

As mentioned above, some of the current revisions involve changes in the documentation, or to add support for other types of LCD.

Log of /Doku/trunk (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/?view=log)
Log of /Software/trunk (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?view=log)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Trilitheum on September 01, 2015, 01:31:17 pm
Hi, I recently purchased the newer DIY kit from Banggood:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

Some of the screen characters are corrupt and I suspect the initial flash was done incorrectly, it does appear to measure accurately and the menus respond.
I have another mega328 on order in case the chip is damaged. I could go back to Banggood but it would be much faster to just re-flash the chip instead of waiting for them to send out a new one.

I know Tom666 posted that the layout is the same as the original and the official firmware can be used:

I found these boards on banggood and I'm thinking to buy one of these.
Which one should I prefer? 16x2 or 128x64 screen? Which one has the latest firmware and which one follows the original schematic with good quality components? Could I reflash the firmware by downloading the latest one from Karl-Heinz's repo?

The quality of the components is the same. In principle, no matter which device you buy, because the only difference is in the used type of LCD and control. Both devices are identical to the basic schematic diagram and can therefore use the official software from Mr. Karl-Heinz.

My questions is which branch directory is the correct build for this board and LCD? The main /mega328, /mega328 GM328?

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 01, 2015, 03:30:32 pm
Hi, I recently purchased the newer DIY kit from Banggood:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)
...
My questions is which branch directory is the correct build for this board and LCD? The main /mega328, /mega328 GM328?

Based on the available information, I recommend to try the directory "mega328_st7565".
Title: Re: $20 LCR ESR Transistor checker project
Post by: Trilitheum on September 01, 2015, 03:49:30 pm
Thanks, will do.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Trilitheum on September 02, 2015, 01:35:34 am
Hmm, didn't work the display is unreadable. Going to try some others.

mega328_wei_st7565/ Appears to display properly, but it's reporting the voltages wrong, looks like half.
Its data layout and font are much different than the original firmware, I am wondering if the creator wrote a custom firmware for these.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firepower on September 02, 2015, 02:56:06 am
go through the make file, there are lots of setting to customise it, one option is to set divider for battery voltage, if thats what is incorrect.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 02, 2015, 11:21:25 am
Hmm, didn't work the display is unreadable. Going to try some others.

mega328_wei_st7565/ Appears to display properly, but it's reporting the voltages wrong, looks like half.
Its data layout and font are much different than the original firmware, I am wondering if the creator wrote a custom firmware for these.

@Trilitheum
Try this actual firmware (v1.12k revision 521) from the attached file (it also includes a modified Makefile).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Trilitheum on September 02, 2015, 12:46:00 pm
Thanks, will try it as soon as I get home.

I'm new to compiling, but I am going to try to get the make file to compile locally as well, figured it will be a good thing to know how to do.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 02, 2015, 04:32:11 pm
Thanks, will try it as soon as I get home.

It's OK, what I here upload (mega328_st7565_kit_v1.12k_r521.zip)?

I'm new to compiling, but I am going to try to get the make file to compile locally as well, figured it will be a good thing to know how to do.

All necessary information you will find in the official manual contained in the SVN repository (http://www.mikrocontroller.net/svnbrowser/transistortester/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Trilitheum on September 03, 2015, 12:17:01 am
Hi, yes that one is better. Thanks!
 
Just a quick question, how did you determine the correct Fuses?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 03, 2015, 06:43:10 am
I used the recommended values of the fuses by the author of the original software (Karl-Heinz Kübbeler) contained in the file "setup.mk".
Title: Re: $20 LCR ESR Transistor checker project
Post by: ulix on September 04, 2015, 08:24:34 am
Hi,
I finished my transistor tester. Sometimes when i test caps it shows me n-d-mos, between pin 1 and 2. Between 1 and 3 it's ok! Is this normal?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 04, 2015, 02:13:57 pm
Hi,
I finished my transistor tester. Sometimes when i test caps it shows me n-d-mos, between pin 1 and 2. Between 1 and 3 it's ok! Is this normal?

No, it shouldn't do that. What kind of caps triggers that issue?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 04, 2015, 05:20:40 pm
Sometimes when i test caps it shows me n-d-mos, between pin 1 and 2. Between 1 and 3 it's ok! Is this normal?

Potential problems:
- faulty port of the MCU
- wiring error

What is the result of the selftest (T1 to T7 values)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ulix on September 04, 2015, 09:08:28 pm
T1 Ref= 1067mV
RHf=872
T2 +RL- 12 13 23 1 1 -4
T3 +RH- 12 13 23 -12 -9 -1
T4 Isolate Probe -12 -9 -1
T5 RH- 0 0 0
T6 -6 -5 -5
T7 RH/RL -1 -1 -1
Ri_Hi=22.5Ohm
Ri_lo=19.7Ohm

The Values change a little, when performing more then once.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 05, 2015, 09:17:10 am
Hi,
I think the self test result is acceptable.
Try therefore to rewrite the firmware and fuses contained in the attached file.
If the issue will no resolved, I guess that is faulty the MCU.

Edit:
Capacitors should always be discharged before measuring!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Protoncek on September 05, 2015, 11:47:55 am
Hello to all!

I've read some pages of this thread but didn't find my problem:
i have chinese GA328 tester with graphic LCD and DIP mega328. FW is 1.11k.
Now...when i make small changes in makefile (change lang to slovene) and i compile it, i get WAY bigger hex file than needed - about 105%, so logically i can't burn it into my mega. Fun thing is that even if i compile a pre-made file, say mega238_st7565 wihtout ANY changes in makefile, i also get too big hex file. What am i doing wrong? I have Windows 10 and WinAVR20100110. For make to work in win10 i've had to replace one file: msys-1.0.dll in folder Utils/bin, otherwise i get compile error no matter what.

I tried FW posted earlier (GM328_EZM_v1.12k_r508_EN) and works, but it's mirrored, so i would have to change that. Also fonts are maybe too big, it could be smaller. And, since i was the one who made SLOVENE translation, it would be really nice to have it in my local language.

And - where do you guys find these latest FW's ? latest on repository i'm aware of is 1.11...
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 05, 2015, 02:51:05 pm
... I've read some pages of this thread but didn't find my problem:
... when i make small changes in makefile (change lang to slovene) and i compile it, i get WAY bigger hex file than needed - about 105%
... if i compile a pre-made file, say mega238_st7565 wihtout ANY changes in makefile, i also get too big hex file. What am i doing wrong? ...

You read this discussion forum very little or absentmindedly :)
It's a notorious problem with the AVR-GCC (using an older version).
This problem has been being solved (several times) in the official discussion forum (http://www.mikrocontroller.net/topic/248078), but also (for example) here:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg692100/#msg692100 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg692100/#msg692100)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg736515/#msg736515 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg736515/#msg736515)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg736815/#msg736815 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg736815/#msg736815)

... And - where do you guys find these latest FW's ? latest on repository i'm aware of is 1.11 ...

The latest version of the software (v1.12k) is still available as a test version. You'll find it here:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Protoncek on September 05, 2015, 03:41:38 pm
Damn...sorry, i don't have any good explanation, how i missed that...i guess i didn't pay much attention on posts regarding "arduino" (since i don't work with it), and now i see that solution is exactly there... i apologize for that.i use WinAVR mainly for making hex fromready-made C programs. Otherwise my strong point is Bascom (sorry...  :-//  )

Many thanks for the tip! I hope i'll manage to solve it.
Thanks for test version of FW also!

I must say that i use this tester more or less daily and it proved a great tool. Up to now i've had simple 2x16 LCD. After i saw that GLCD is possible i wanted to build a new one from scratch, but i saw that ready-made from china is cheaper...
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 05, 2015, 04:11:41 pm
...
After i saw that GLCD is possible i wanted to build a new one from scratch, but i saw that ready-made from china is cheaper ...

If I may advise, so definitely I recommend this KIT:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

Seller can send this KIT directly from the EU - before ordering to be selected "EU Warehouse".

Here we solved the software for this tester:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg745437/#msg745437 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg745437/#msg745437)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 05, 2015, 04:59:38 pm
Please, help me. I don't know identify the connector (type or manufacturer) on the attached pictures.
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Protoncek on September 05, 2015, 06:09:28 pm
OK, i've got it running, although not without struggle. First time after copying i've got some errors while compiling (some dll's not found...?). Then i uninstalled WInAVR, updated arduino and after that IF YOUR'RE WINDOWS 10 user, it's necesarry to copy/overwrite one file: msys-1.0.dll. Without it you'll get a ton of errors while compiling.

Now i already have my tester in Slovenian.

Many thanks again, Tom!

EDIT: I found one "odd" behaviour: when i measure capacitor and i connect it on pins 1 and 3 tester automatically goes into permanent measuring mode, consequently it never goes off. This doesn't happen if i connect it on pins 1-2 or 2-3. Is this behaviour ment to be this way?
(FW is v1.12)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 06, 2015, 03:40:39 pm
I found one "odd" behaviour: when i measure capacitor and i connect it on pins 1 and 3 tester automatically goes into permanent measuring mode, consequently it never goes off. This doesn't happen if i connect it on pins 1-2 or 2-3. Is this behaviour ment to be this way? (FW is v1.12)

This is a new feature of the version 1.12k - separately measuring C and R. This mode is automatically activated if you have connected these passive components on the test points 1 and 3. Read more in the official manual (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Protoncek on September 06, 2015, 04:45:06 pm
Great. Once i'll get used to connect these components properly, i guess it will become very usefull function.
I guess the easiest way to shut down from this state is remove component and press test button, which will result in "no component" and shut down.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on September 07, 2015, 09:22:25 am
Tacking on a pushbutton to ground the Reset pin makes a very convenient 'Off' button.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 07, 2015, 12:00:00 pm
Exactly this is also used for forced power off in the Fish8840 tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on September 09, 2015, 02:12:32 am
Please, help me. I don't know identify the connector (type or manufacturer) on the attached pictures.
Thanks

Hi Tom666,

Tried searching with fotoforensics ans google image with no luck. What is the connector for and what is it installed on..maybe that would help lookup some other sources.
Tks,

Raymond
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 09, 2015, 07:57:06 am
Hi Raymond,
thank you very much for your efforts and willingness to help me in the search. The connector is part of the tester case sold here (http://www.banggood.com/Supporting-Shell-For-DIY-M12864-Graphics-Version-Transistor-Tester-Kit-p-989949.html). This connector I really like as an alternative to ZIF socket.
Thanks again.

bye
Tomas
Title: Re: $20 LCR ESR Transistor checker project
Post by: Trilitheum on September 09, 2015, 03:41:12 pm
Hi, I have the tester kit and I checked the white connector and there are no identifying marks on it at all.
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 10, 2015, 03:32:21 am
hello to all, i recently buy a mk-328 tester, it comes loaded with 1.11k with no menu enabled (dont know if menu is usefull in this model because it have a case), somebody can lead me to a prebuilt 1.12k firmware or tell me which version of the svn trunk is the right one?

photos:

http://www.mikrocontroller.net/topic/248078?page=7#4109458 (http://www.mikrocontroller.net/topic/248078?page=7#4109458)

any help will be really appreciated.

best regards

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 10, 2015, 07:27:54 pm
According to the available information, you should use folder "mega328_st7565".
Try the attached file contains a compiled software (v1.12k r521} with a modified file "Makefile".

Setting of fuses for the ATmega328p:
lfuse:0xf7 hfuse:0xd9 efuse:0x04 [0xfc]
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 11, 2015, 01:28:40 am
thank you very much! i wil try it and publish results as soon as possible,


best regards


Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on September 12, 2015, 11:17:48 am
Please, help me. I don't know identify the connector (type or manufacturer) on the attached pictures.
Thanks

Hi Tom666,

Made numerous searches, spent a few hours and this is a very difficult connector to find! I ended up on digikey which allows to search in many ways and although I didn't find the exact one, here on this page there are similar connectors:

http://www.digikey.com/product-search/en?pv88=24&FV=fff40016%2Cfff802f9&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25 (http://www.digikey.com/product-search/en?pv88=24&FV=fff40016%2Cfff802f9&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25)

But don't stop on that page if you go to "product index", you can do all sorts of searches. I'll keep looking, but if we are a few of us, maybe someone will stumble upon it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on September 12, 2015, 12:11:50 pm
Hi Tom666,

I could find the wanted socket on aliexpress.com:
http://www.aliexpress.com/item/10pcs-Transistor-Triode-testing-socket-aging-test-seat-high-power-tube-test-socket-For-TO92-TO220/32353462427.html?spm=2114.01020208.3.9.jp3y0P&ws_ab_test=201407_4,201444_5,201409_4 (http://www.aliexpress.com/item/10pcs-Transistor-Triode-testing-socket-aging-test-seat-high-power-tube-test-socket-For-TO92-TO220/32353462427.html?spm=2114.01020208.3.9.jp3y0P&ws_ab_test=201407_4,201444_5,201409_4)
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on September 12, 2015, 02:32:00 pm
Hi Tom666,

I could find the wanted socket on aliexpress.com

I gotta love this forum. Is there no question that cannot be answered here?  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 12, 2015, 02:48:00 pm
Many thanks, gentlemen :-+ :clap:

Best regards
Tomas
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on September 13, 2015, 01:10:13 am
Hi Tom666,

I could find the wanted socket on aliexpress.com:
http://www.aliexpress.com/item/10pcs-Transistor-Triode-testing-socket-aging-test-seat-high-power-tube-test-socket-For-TO92-TO220/32353462427.html?spm=2114.01020208.3.9.jp3y0P&ws_ab_test=201407_4,201444_5,201409_4 (http://www.aliexpress.com/item/10pcs-Transistor-Triode-testing-socket-aging-test-seat-high-power-tube-test-socket-For-TO92-TO220/32353462427.html?spm=2114.01020208.3.9.jp3y0P&ws_ab_test=201407_4,201444_5,201409_4)

Hey, great job Willem52! Also found it can be purchased in lot of 2 on here:

http://pt.aliexpress.com/item/2pcs-Transistor-Triode-Test-Socket-Ageing-Test-Socket-Ceramics-Body-TO92-TO220-TO3P/32355460406.html?spm=2114.01020208.3.18.uMn5yC&ws_ab_test=201407_2,201444_6,201409_2 (http://pt.aliexpress.com/item/2pcs-Transistor-Triode-Test-Socket-Ageing-Test-Socket-Ceramics-Body-TO92-TO220-TO3P/32355460406.html?spm=2114.01020208.3.18.uMn5yC&ws_ab_test=201407_2,201444_6,201409_2)

I think it is Aliexpress in Portugal?

Regards,

Raymond
Title: Re: $20 LCR ESR Transistor checker project
Post by: nowlan on September 13, 2015, 03:18:29 am
Is easier to buy the case with the socket already?
http://www.banggood.com/Supporting-Shell-For-DIY-M12864-Graphics-Version-Transistor-Tester-Kit-p-989949.html (http://www.banggood.com/Supporting-Shell-For-DIY-M12864-Graphics-Version-Transistor-Tester-Kit-p-989949.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on September 13, 2015, 04:13:34 am
Help please:

I have a voltage regulator like the one pictured, brand new. When I insert it in the transistor tester (I have 2 of them and the both give same results), I get a message "Part damaged or unkown ?? ".

Does the transistor tester recognize this type of voltage regulator or is there something wrong with my tt's ?

(http://www.kpcomponents.ca/images/KIA7812API.jpg)

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 13, 2015, 05:29:44 am
just a question, the frequency counter function in firmware 1.12k supports analog signals or just digital?

best regards

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on September 13, 2015, 06:34:41 am
The Transistor Tester is not capable of detecting
78xx, 79xx or LM 3xx voltage regulators, for example.
Even so, it is a highly versatile tool! It had better be called
"Component Tester". Anyhow.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 13, 2015, 08:29:14 am
just a question, the frequency counter function in firmware 1.12k supports analog signals or just digital?

I think that what is important is the sufficient level of the test signal. For best input sensitivity it is necessary to set the supplement as described in the manual (2.2.4 Frequency measurement).

Works firmware that I uploaded for you in the previous post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg751644/#msg751644)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on September 13, 2015, 12:32:31 pm
Does the transistor tester recognize this type of voltage regulator or is there something wrong with my tt's ?

I am far from qualified to say, but would think it very challenging to automatically detect and test a LM78xx voltage regulator within the scope of everything else this design does, without causing damage to components it already tests for. There are at least 3 challenges that I can think of off the top:

The 78xx series needs a supply voltage 2.5v higher than the regulated voltage, so in the case of the LM7812 pictured, it would have to apply 14.5 volts to the input. Not only does that have to come from the 9v battery, it can't cause damage to the low voltage devices this is designed to test.

The 78xx series come in a TO-220 case but are really more of a 3 terminal IC than a component. I don't know exactly what the transistor count is, but it's a busy little block diagram in the datasheet.

The 78xx series require a couple of external components to function properly. I think those would have to be switched into the circuit during the detection/test phase to properly test the output.

Of course, given all the challenges the designers have already overcome, I would never say "never"! But for the moment, maybe you are better to whip up a discrete test circuit of your own. Don't forget to add a heat sink to that thing if you draw more than 500mA while testing, or the thermal overload protection may shut it down, making it appear to fail the test.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 13, 2015, 01:36:17 pm
Hello, friends! I ask forgiveness for my English in advance. I use the translator. For determination of parameters of voltage reference diodes and power conditioners there is a finishing of the hardware of a tester. Here one of possible diagrams which is developed and checked by the participant of the forum Vrtp.ru dear Ocela.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 13, 2015, 04:46:52 pm
Hi,
some time ago I drew attention to this great kit:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

This tester is supplied with an earlier revision of the software v1.12k by Karl-Heinz Kübbeler.

Is used the G-LCD display with the controller ST7565 (in the standart SPI mode).

For other owners of this great kit I offer in the attached file recent version 1.12k (revision 523). It also includes a modified file "Makefile" for this tester. I tested this firmware.

Setting of the fuses [ATmega328p]:
lfuse:0xf7 hfuse:0xd9 efuse:0x04 [0xfc]

Note:
For reduce power consumption I recommend to change the series resistor for the LED backlight G-LCD to 680 ohm (the original value is 220 ohm). A further reduction in consumption could be achieved by replacing the 7550-1 to the Low Drop LDO (eg MCP1702-5002).

Bye
Tomas
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 14, 2015, 03:56:12 am
just a question, the frequency counter function in firmware 1.12k supports analog signals or just digital?

I think that what is important is the sufficient level of the test signal. For best input sensitivity it is necessary to set the supplement as described in the manual (2.2.4 Frequency measurement).

Works firmware that I uploaded for you in the previous post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg751644/#msg751644)?

thank you, no yet, i have no experience in programming microcontrollers, i am trying learn to use avrdude, unless you can please point me with the right instrucctions (commands) for backup the existing firmware and flash the new one you kindly provide to me, by the way already have an usbasp and installed already avrdude in linux and windows.

thank you in advance.

best regards

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on September 14, 2015, 04:48:43 am
Hello, friends! I ask forgiveness for my English in advance. I use the translator. For determination of parameters of voltage reference diodes and power conditioners there is a finishing of the hardware of a tester. Here one of possible diagrams which is developed and checked by the participant of the forum Vrtp.ru dear Ocela.

Is this a separate tester, just for regulators such as the LM78xx series? Or is it a new feature added to the transistor tester?

(Just wondering how wrong I was!  ;) )
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 14, 2015, 06:54:50 am
Is this a separate tester, just for regulators such as the LM78xx series? Or is it a new feature added to the transistor tester?
(Just wondering how wrong I was!  ;) )
No, it not a separate tester. The basic firmware from Karl-Heinz Kübbeler with function of measurement of voltage reference diodes is used. Changes are made only in the tester hardware  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 14, 2015, 11:49:37 am
i am trying learn to use avrdude, unless you can please point me with the right instrucctions (commands) for backup the exiting firmware and flash the new one you kindly provide to me, by the way already have an usbasp and installed already avrdude in linux and windows.

Commands for Windows

Writing Flash + EEPROM + Fuses:
avrdude -c usbasp -p m328p -B 0.5 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

Reading Flash + EEPROM:
avrdude -c usbasp -p m328p -B 0.5 -U flash:r:"TransistorTester_Backup.hex":i -U eeprom:r:"TransistorTester_Backup.eep":i

Another option is to use a GUI for AVRDUDE. I recommend AVRDUDESS (http://blog.zakkemble.co.uk/avrdudess-a-gui-for-avrdude/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on September 14, 2015, 12:26:02 pm
No, it not a separate tester. The basic firmware from Karl-Heinz Kübbeler with function of measurement of voltage reference diodes is used. Changes are made only in the tester hardware  :D

Well then. I guess I was almost completely wrong. How extensive are the hardware changes? Is this fork being made available in the same way as the original Karl-Heinz transistor tester?
Title: Re: $20 LCR ESR Transistor checker project
Post by: quantalume on September 14, 2015, 04:25:22 pm
Hi,
some time ago I drew attention to this great kit:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

This tester is supplied with an earlier revision of the software v1.12k by Karl-Heinz Kübbeler.

Is used the G-LCD display with the controller ST7565 (in the standart SPI mode).

For other owners of this great kit I offer in the attached file recent version 1.12k (revision 523). It also includes a modified file "Makefile" for this tester. I tested this firmware.

Setting of the fuses [ATmega328p]:
lfuse:0xf7 hfuse:0xd9 efuse:0x04 [0xfc]

Note:
For reduce power consumption I recommend to change the series resistor for the LED backlight G-LCD to 680 ohm (the original value is 220 ohm). A further reduction in consumption could be achieved by replacing the 7550-1 to the Low Drop LDO (eg MCP1702-5002).

Bye
Tomas

It is indeed a great kit! Does one need to change the fuses from how they are supplied with the kit in order to run the new firmware?

Thanks for the suggestions for reducing power consumption. One could also increase the resistor value for the power LED as it's blinding in its current state.

Do you know of a case for this unit?  The case you linked to in the message where you introduced this kit (reply #1144, page 77) appears to be for a different design.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 14, 2015, 04:39:24 pm
How extensive are the hardware changes? Is this fork being made available in the same way as the original Karl-Heinz transistor tester?
Hi! Any tranzistortester it is simple to finish most. In the simplified look the converter DC-DC having on an output 35-40V for testing of voltage reference diodes and chips of stabilizators 78xx is necessary. The principle of such measurement explained Karl-Heinz Kübbeler in the instruction to the instrument on page 11. Maybe I badly explain? Excuse for my English. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on September 14, 2015, 05:12:17 pm
Many thanks, gentlemen :-+ :clap:

Best regards
Tomas

Here they can be bought individually, but I think rather expensive? What do you think?

http://www.ebay.com/itm/Transistor-Triode-Test-Socket-Ageing-Test-Socket-Ceramics-Body-TO92-TO220-TO3P-/311360707052 (http://www.ebay.com/itm/Transistor-Triode-Test-Socket-Ageing-Test-Socket-Ceramics-Body-TO92-TO220-TO3P-/311360707052)

Tom666, why do you feel this is a much better connector than the zif socket? Should I change mine on my transistor tester? Tks
Title: Re: $20 LCR ESR Transistor checker project
Post by: klunkerbus on September 14, 2015, 05:52:28 pm
rddube, the ZIF socket doesn't work out very well if you're installing the banggood tester with the 128x64 display into the plastic case that banggood offers for it.  (see http://www.banggood.com/Supporting-Shell-For-DIY-M12864-Graphics-Version-Transistor-Tester-Kit-p-989949.html (http://www.banggood.com/Supporting-Shell-For-DIY-M12864-Graphics-Version-Transistor-Tester-Kit-p-989949.html) ) That could be one reason. 

I just assembled my tester and case, and I think I'd prefer the ZIF socket.  I've already been struggling to insert thin leads into the 5-pin socket without bending them. The contact fingers also look extremely cheap, and I won't be surprised if the contacts loose their grip with use.  For packages like TO-220, the 5-pin socket probably works great. 

On the eBay part, the higher cost might make sense if it was truly a ceramic body, but the listing pictures don't convince me. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 14, 2015, 07:00:16 pm
Does one need to change the fuses from how they are supplied with the kit in order to run the new firmware?

In principle there is no need, but I recommend use a values of the software author.

One could also increase the resistor value for the power LED as it's blinding in its current state.

Not recommended, it can then be a problem with the auxiliary power circuits.

The case you linked to in the message where you introduced this kit (reply #1144, page 77) appears to be for a different design.

The case, to which I post link is definitely designed for this kit. Please, see you the pictures carefully to the seller's site. ZIF socket for this case will not be used.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 14, 2015, 07:06:05 pm
The case you linked to in the message where you introduced this kit (reply #1144, page 77) appears to be for a different design.

The case, to which I post link is definitely designed for this kit. Please, see you the pictures carefully to the seller's site. ZIF socket for this case will not be used.

Exactly.

Quantalume, if you're going to use that case, don't install the ZIF socket on the PCB. Instead, use the socket that is supplied with the case. (i.e., It's not like cases for the other tester kits where the ZIF socket passes through an opening.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 14, 2015, 07:14:19 pm
Tom666, why do you feel this is a much better connector than the zif socket? Should I change mine on my transistor tester?

In terms of design could be easier mounting on the case compared to ZIF socket. But I have some doubts about the quality of this connector.
Title: Re: $20 LCR ESR Transistor checker project
Post by: quantalume on September 14, 2015, 07:28:23 pm
Exactly.

Quantalume, if you're going to use that case, don't install the ZIF socket on the PCB. Instead, use the socket that is supplied with the case. (i.e., It's not like cases for the other tester kits where the ZIF socket passes through an opening.)

OK, I see how it works now. Too bad I already soldered the ZIF socket.  |O  Nothing a solder sucker can't fix I suppose.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 14, 2015, 08:22:18 pm
OK, I see how it works now. Too bad I already soldered the ZIF socket.  |O  Nothing a solder sucker can't fix I suppose.

Yep. All part of the DIY fun.  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: quantalume on September 15, 2015, 02:54:44 pm
Tom666, why do you feel this is a much better connector than the zif socket? Should I change mine on my transistor tester?

In terms of design could be easier mounting on the case compared to ZIF socket. But I have some doubts about the quality of this connector.

Could one cut the case to allow the ZIF socket to be used instead? I also see that there are only two binding posts. Could a third post be squeezed in and still leave room for the battery?
Title: Re: $20 LCR ESR Transistor checker project
Post by: giovannirat on September 15, 2015, 07:33:49 pm
As soon as i will get the case i try to cut it for the ZIF socket.

Thank you tom666 for providing the actual software. Works great.

Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on September 16, 2015, 01:03:14 am
Tom666, why do you feel this is a much better connector than the zif socket? Should I change mine on my transistor tester?

In terms of design could be easier mounting on the case compared to ZIF socket. But I have some doubts about the quality of this connector.

Could one cut the case to allow the ZIF socket to be used instead? I also see that there are only two binding posts. Could a third post be squeezed in and still leave room for the battery?

I plan to investigate the same questions when mine arrives this week.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 16, 2015, 01:44:38 am
I plan to investigate the same questions when mine arrives this week.

I'm looking forward to seeing everyone's case mods. I ordered one of the testers with the encoder, but not the case (yet).
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 16, 2015, 06:58:55 am
As soon as i will get the case i try to cut it for the ZIF socket.

Very elegant solution :-+ :clap:
Thank you for the inspiration.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 17, 2015, 07:02:26 pm
Just a quick update on the m-firmware. Currently I'm working on a driver for ILI8341/ILI8342 based colour LCD modules and larger fonts. I'll also try to add the fancy pinout in the next version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 18, 2015, 04:24:17 pm
Hello,

I need help guys in figuring out whats wrong, i have one of these LCR ESR Transistor checker with case, very handy gadget, till one day i accidentaly dropped it, screen cracked so i looked for a replacement 12864 lcd module, bought a bigger size lcd bec i cant find exact size, and when i hooked it up to the characters are inverted, photos attached, thanks in advance...

LCD module link
http://www.aliexpress.com/item/JLX12864G-378B-PC-12864-lattice-COG-type-serial-and-optionally-3-3v-5V-optional/32278219453.html (http://www.aliexpress.com/item/JLX12864G-378B-PC-12864-lattice-COG-type-serial-and-optionally-3-3v-5V-optional/32278219453.html)

Transistor Tester link
http://www.aliexpress.com/item/Multi-functional-LCD-Display-Digital-ESR-Meter-Transistor-Tester-Diode-Thyristor-Capacitance-LCR-Tester-Grey-Plastic/32423335203.html?spm=2114.01020208.8.78.y2luTw (http://www.aliexpress.com/item/Multi-functional-LCD-Display-Digital-ESR-Meter-Transistor-Tester-Diode-Thyristor-Capacitance-LCR-Tester-Grey-Plastic/32423335203.html?spm=2114.01020208.8.78.y2luTw)

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 18, 2015, 04:31:41 pm
I need help guys in figuring out whats wrong, i have one of these LCR ESR Transistor checker with case, very handy gadget, till one day i accidentaly dropped it, screen cracked so i looked for a replacement 12864 lcd module, bought a bigger size lcd bec i cant find exact size, and when i hooked it up to the characters are inverted, photos attached, thanks in advance...

You need to compile the firmware with options set to match your display. There are options to flip x and y.
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 18, 2015, 04:59:45 pm
I need help guys in figuring out whats wrong, i have one of these LCR ESR Transistor checker with case, very handy gadget, till one day i accidentaly dropped it, screen cracked so i looked for a replacement 12864 lcd module, bought a bigger size lcd bec i cant find exact size, and when i hooked it up to the characters are inverted, photos attached, thanks in advance...

You need to compile the firmware with options set to match your display. There are options to flip x and y.

Oh :), thanks very much @madires, ive been doing back reading & thanks to your hard work guys there are firmwares that i can try to work on to, just woried though bec my minipro TL866A (Converted from CS to A Thanks to this forum :-+) cannot read this through ICSP, gonna give it a try tomorow, Thanks again  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 19, 2015, 10:15:00 am
FYI

Hello friends,
recently, the author of the software (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) (Karl-Heinz Kübbeler (kubi48)) working intensively on its improvement :clap: :-+ Proof of this is a new function that extend the testing of small capacitors (<100pF) by use of a sampling mode for the ADC converter. Extend the resolution of measurement is about 0.01pF. To enable this new functionality is necessary to enable in the Makefile this setting "WITH_SamplingADC = 1". It is designed only for M328 and higher MCUs.

Bye
Tomas
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 19, 2015, 11:34:42 am
I need help guys in figuring out whats wrong, i have one of these LCR ESR Transistor checker with case, very handy gadget, till one day i accidentaly dropped it, screen cracked so i looked for a replacement 12864 lcd module, bought a bigger size lcd bec i cant find exact size, and when i hooked it up to the characters are inverted, photos attached, thanks in advance...

You need to compile the firmware with options set to match your display. There are options to flip x and y.

Oh :), thanks very much @madires, ive been doing back reading & thanks to your hard work guys there are firmwares that i can try to work on to, just woried though bec my minipro TL866A (Converted from CS to A Thanks to this forum :-+) cannot read this through ICSP, gonna give it a try tomorow, Thanks again  :)

Hello guys, i just flashed my Fish8840 with case tester with "ComponentTester-trendy-1.18m" by Markus, just as @madires said that i have to look for options how to flip the display to work with my LCD module replacement, so i edited config.h, after flashing the display worked properly but the tester is measruring the battery voltage as 16volts and it goes into a probe loop, so now i will try flashing my tester with other firmwares on this thread and il report back, thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 19, 2015, 12:26:22 pm
Original voltage divider for battery voltage measurement is 10k and 3.3k.
By contrast, the tester Fish8840 used divider with values 47K and 47K.

Note:
Please, use the "quotes" wisely.
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 19, 2015, 12:48:20 pm
Thanks @tom666 :), found a working firmware for my Fish8840 tester here:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)

I dont know why but the 680ohm resistor inline with the MISO pin opened up, Thanks for the guidance guys :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 19, 2015, 12:53:54 pm
Edit:
Use this actual firmware for the Fish8840 Tester:
Fish8840_v1.12k_r554.zip (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=172182)
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 19, 2015, 01:14:43 pm
@tom666, the new firmware you provided works  :-+, nice bold like font too, il do further testing after i replace the open 680ohm ressitor and report back thanks a lot.... :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 19, 2015, 01:47:04 pm
I'm glad :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 19, 2015, 02:23:28 pm
Friends, Karl-Heinz Kübbeler added the very useful and significant changes to fresh audits of a firmware!
Changes concerned the accuracy of samplings of capacities to 100pf. One of participants of the forum mikrocontroller.net suggested to add in makefile a line "WITH_SamplingADC = 1" that increases permission in this range to 0,01pf. Measurement needs to be done on TP1-TP3 pins.
One more addition - the author realized correction of indications of "big" capacities in the additional menu! There was a "Cap correction" point. Values can be changed from-2.0% to +8.0%. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 20, 2015, 08:51:30 am
Hello, fully tested the newest firmware from tom666 for my fish8840 tester and its realy great  :-+, i have another tester waiting to be picked up in the post, its also fish8840 but with black case, thanks guys...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2015, 03:30:35 pm
Friends, Karl-Heinz Kübbeler added the very useful and significant changes to fresh audits of a firmware!
Changes concerned the accuracy of samplings of capacities to 100pf. One of participants of the forum mikrocontroller.net suggested to add in makefile a line "WITH_SamplingADC = 1" that increases permission in this range to 0,01pf. Measurement needs to be done on TP1-TP3 pins.

The additional measurement for low capacitance was submitted by PA3FWM. There will be also one for low inductance (based on a resonant circuit with a parallel known C). The problem is that the firmware with both new features and support for a graphic LCD module will exceed the flash size limit of the ATmega328. The classic HD44780 testers should be fine (for some time). Anyway, we're heading to the 644/1284 to allow new features and options. On my todo list is support for touchscreens which requires some additional I/O pins, the 328 doesn't have.

BTW, the low capacitance measurement is very sensible to probe wires and ZIFs/test sockets. Karl-Heinz mentioned that the difference between an opened and closed ZIF is about 0.6pF and that probe wires are a no-go.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on September 20, 2015, 04:54:14 pm
Sorry for taking the thread off topic for a short detour on the immediate local road but I've been watching this thread for a while as it progresses toward 100 pages....

Any chance that this particular product might be a reasonable contender?

http://www.ebay.com/itm/New-Small-12864-LCD-Transistor-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/171815404897?_trksid=p2046732.c100040.m2060&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140107095009%26meid%3D4bf4a0d9d5fe4256add580abc3381565%26pid%3D100040%26rk%3D1%26rkt%3D4%26sd%3D171815404897 (http://www.ebay.com/itm/New-Small-12864-LCD-Transistor-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/171815404897?_trksid=p2046732.c100040.m2060&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140107095009%26meid%3D4bf4a0d9d5fe4256add580abc3381565%26pid%3D100040%26rk%3D1%26rkt%3D4%26sd%3D171815404897)

Or is there something similar (already built, not a kit) that might be a better gift for a student to use as a simple component tester?  Just looking for something that gives hands-on experience / feedback / measurements on a variety of components.  Thx
Title: Re: $20 LCR ESR Transistor checker project
Post by: Overtuner on September 20, 2015, 05:03:32 pm
The problem is that the firmware with both new features and support for a graphic LCD module will exceed the flash size limit of the ATmega328. The classic HD44780 testers should be fine (for some time). Anyway, we're heading to the 644/1284 to allow new features and options. On my todo list is support for touchscreens which requires some additional I/O pins, the 328 doesn't have.
644/1284 because of the 20MHz clock? - well done, it improves the felt speed with higher resolution displays on old-school-8bit-mcu's  8)
the bad thing with them ist the restriction to TQFP-44.

Quote
BTW, the low capacitance measurement is very sensible to probe wires and ZIFs/test sockets. Karl-Heinz mentioned that the difference between an opened and closed ZIF is about 0.6pF and that probe wires are a no-go.
to solve this, I'd recommend to "duplicate" the circuitry for the three test pins, one set on ZIF, the other on wires.
most well designed self-made testers have already a ZIF (or other 3pin) socket AND probe wires on 2mm banana jacks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on September 20, 2015, 06:27:37 pm
Quote
the bad thing with them ist the restriction to TQFP-44.

??
As far as I can see there are DIL40 644s and 1284s.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on September 21, 2015, 05:37:03 am
not sure if these were posted previously; if not they might be helpful

Battery Life Improvement Mod:
https://www.youtube.com/watch?v=gx55Gza0zGE (https://www.youtube.com/watch?v=gx55Gza0zGE)

General Review:
https://www.youtube.com/watch?v=Z705XVfkb5w (https://www.youtube.com/watch?v=Z705XVfkb5w)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Overtuner on September 21, 2015, 09:44:59 am
Quote
the bad thing with them ist the restriction to TQFP-44.

??
As far as I can see there are DIL40 644s and 1284s.

of course, yes.
but who wants to have such large bricks of plastics?  ;D

if I had a wish for free - a mega256, with 25MHz, integrated USB like the U4 - within a TQFP-64  ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 21, 2015, 10:15:16 am
not sure if these were posted previously; if not they might be helpful

Some information (about Fish8840 Tester) has been already published some time ago.
For example:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg639330/#msg639330 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg639330/#msg639330)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg643885/#msg643885 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg643885/#msg643885)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg644055/#msg644055 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg644055/#msg644055)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg644091/#msg644091 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg644091/#msg644091)

In the attached pdf document you will find extracted part from the official manual:
https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/)

Another option is upgrade to the software by Karl-Heinz Kübbeler:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)

Backup of the original firmware in case of restoring the original software is available here:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg639330/#msg639330 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg639330/#msg639330)

Bye
Tomas
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 21, 2015, 12:44:42 pm
Hello :( , aftr a month of waitng i got my 2nd tester from the post office, and when bad luck strikes yay  :( another cracked screen  :palm:

another LCD hunting and i hope this time il get the correct dimensions....
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on September 21, 2015, 12:50:09 pm
Isn't the 12864 LCD fairly standard in size?
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 21, 2015, 01:30:44 pm
No @neslekkim, these testers with case (Fish8840) use 12864 lcd,s with dimensions of 46mmx29mm LxW to propperly fit on the viewing window of the case, a ST7565 Driver and a 12 pin flex flat bar solder connection directly soldered on the atmega328 pcb. there are many 12864 lcd modules on ebay and aliexpress but im having trouble finding the right connector and dimension.
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on September 21, 2015, 02:20:04 pm
No @neslekkim, these testers with case (Fish8840) use 12864 lcd,s with dimensions of 46mmx29mm LxW to propperly fit on the viewing window of the case, a ST7565 Driver and a 12 pin flex flat bar solder connection directly soldered on the atmega328 pcb. there are many 12864 lcd modules on ebay and aliexpress but im having trouble finding the right connector and dimension.

Ah, without the frame, I have the earlier types which uses the types with pinheader, but maybe this would be close?
http://www.ebay.com/itm/271760155514 (http://www.ebay.com/itm/271760155514)

And I would guess that if you send a message to the seller about yours, maybe he would provide you new display?

Do you have link to the two you bought?
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 21, 2015, 02:40:28 pm
Here you go @neslekkim
http://www.aliexpress.com/item/Multi-functional-LCD-Backlight-Transistor-Tester-Diode-Thyristor-Capacitance-ESR-Meter-Tester-LCR-with-Grey-Plastic/32322667293.html (http://www.aliexpress.com/item/Multi-functional-LCD-Backlight-Transistor-Tester-Diode-Thyristor-Capacitance-ESR-Meter-Tester-LCR-with-Grey-Plastic/32322667293.html)

and the firmware posted by tom666 on page 84 works great on this  :-+

Title: Re: $20 LCR ESR Transistor checker project
Post by: ralphd on September 21, 2015, 03:48:29 pm
Friends, Karl-Heinz Kübbeler added the very useful and significant changes to fresh audits of a firmware!
Changes concerned the accuracy of samplings of capacities to 100pf. One of participants of the forum mikrocontroller.net suggested to add in makefile a line "WITH_SamplingADC = 1" that increases permission in this range to 0,01pf. Measurement needs to be done on TP1-TP3 pins.

The additional measurement for low capacitance was submitted by PA3FWM. There will be also one for low inductance (based on a resonant circuit with a parallel known C). The problem is that the firmware with both new features and support for a graphic LCD module will exceed the flash size limit of the ATmega328. The classic HD44780 testers should be fine (for some time). Anyway, we're heading to the 644/1284 to allow new features and options. On my todo list is support for touchscreens which requires some additional I/O pins, the 328 doesn't have.

Have you tried avr-gcc 4.9.2 or 5.0 with LTO?  10-20% code size reductions with LTO are fairly common.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 21, 2015, 04:55:13 pm
Have you tried avr-gcc 4.9.2 or 5.0 with LTO?  10-20% code size reductions with LTO are fairly common.

Not yet. My current avr-gcc version is 4.8.1. But thanks for the hint!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 21, 2015, 04:59:21 pm
644/1284 because of the 20MHz clock? - well done, it improves the felt speed with higher resolution displays on old-school-8bit-mcu's  8)

The ATmega168/328 also runs up to 20MHz. And the k & m firmwares support 16MHz for quite a while.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 21, 2015, 05:07:12 pm
and the firmware posted by tom666 on page 84 works great on this  :-+

The attached file contains firmware that I recommend use. This version (v1.12k r554) is without a new features (WITH_SamplingADC = 1), because this new method of measurement is currently in constant and intensive development.
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 21, 2015, 05:44:29 pm
 :)Ok, gonna flash this one tomorow thanks  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: giovannirat on September 21, 2015, 06:01:46 pm
@tom666   it would be great if you could provide the software  M328_ST7565_KIT_v1.12k_r523  in this actual version r554 ........ :clap:

Thank you....
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on September 21, 2015, 06:37:32 pm
Is this:

http://www.ebay.com/itm/New-Small-12864-LCD-Transistor-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/171815404897?_trksid=p2046732.c100040.m2060&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140107095009%26meid%3D4bf4a0d9d5fe4256add580abc3381565%26pid%3D100040%26rk%3D1%26rkt%3D4%26sd%3D171815404897 (http://www.ebay.com/itm/New-Small-12864-LCD-Transistor-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/171815404897?_trksid=p2046732.c100040.m2060&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140107095009%26meid%3D4bf4a0d9d5fe4256add580abc3381565%26pid%3D100040%26rk%3D1%26rkt%3D4%26sd%3D171815404897)

The same as the item below in terms of functionally?  Just repackaged inside the case?

http://www.aliexpress.com/item/Multi-functional-LCD-Backlight-Transistor-Tester-Diode-Thyristor-Capacitance-ESR-Meter-Tester-LCR-with-Grey-Plastic/32322667293.html (http://www.aliexpress.com/item/Multi-functional-LCD-Backlight-Transistor-Tester-Diode-Thyristor-Capacitance-ESR-Meter-Tester-LCR-with-Grey-Plastic/32322667293.html)

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 21, 2015, 06:41:36 pm
Yes elctro fan, theyre basicaly the same, the tester with case has no smd test pads though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 21, 2015, 06:46:52 pm
Oh, il gonna post PCB photos of tester with case tomorow. :) "Dont turn it On...Tear it appart" hehehe
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 21, 2015, 07:10:10 pm
@tom666   it would be great if you could provide the software  M328_ST7565_KIT_v1.12k_r523  in this actual version r554.

Here you are firmware v1.12k revision 555 for this great kit (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on September 21, 2015, 07:15:46 pm
Yes elctro fan, theyre basicaly the same, the tester with case has no smd test pads though.

Thanks - are you pretty sure the display is the same?  Are there any eBay sellers you have seen with the case and the same display and parts inside?  Thanks again, EF
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 21, 2015, 07:53:07 pm
Is this:

http://www.ebay.com/itm/New-Small-12864-LCD-Transistor-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/171815404897?_trksid=p2046732.c100040.m2060&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140107095009%26meid%3D4bf4a0d9d5fe4256add580abc3381565%26pid%3D100040%26rk%3D1%26rkt%3D4%26sd%3D171815404897 (http://www.ebay.com/itm/New-Small-12864-LCD-Transistor-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/171815404897?_trksid=p2046732.c100040.m2060&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140107095009%26meid%3D4bf4a0d9d5fe4256add580abc3381565%26pid%3D100040%26rk%3D1%26rkt%3D4%26sd%3D171815404897)

The same as the item below in terms of functionally?  Just repackaged inside the case?

http://www.aliexpress.com/item/Multi-functional-LCD-Backlight-Transistor-Tester-Diode-Thyristor-Capacitance-ESR-Meter-Tester-LCR-with-Grey-Plastic/32322667293.html (http://www.aliexpress.com/item/Multi-functional-LCD-Backlight-Transistor-Tester-Diode-Thyristor-Capacitance-ESR-Meter-Tester-LCR-with-Grey-Plastic/32322667293.html)

Thanks

@EF, both of these testers use 12864 LCDs, they're both from fish8840, both are on firmware 2.1 mod by wieweitm, i dont know about the dimensions of the lcd of the tester without case but for the tester with case it needs to be 46mmx29mm LxW to fit on the viewing window of the tester, the lcd has no header connectors so the flex cable is directly soldered to the MCU pcb and the display is white chars on black background, both testers have 2 tac switches, the MCU section of both testers basically same, the power section of my tester has unpopulated area and it looks like a dc in jack and lithium battery charging ckt. both runs on 9v batt, il post photos tomorow  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 21, 2015, 09:09:02 pm
i am trying learn to use avrdude, unless you can please point me with the right instrucctions (commands) for backup the exiting firmware and flash the new one you kindly provide to me, by the way already have an usbasp and installed already avrdude in linux and windows.

Commands for Windows

Writing Flash + EEPROM + Fuses:
avrdude -c usbasp -p m328p -B 0.5 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

Reading Flash + EEPROM:
avrdude -c usbasp -p m328p -B 0.5 -U flash:r:"TransistorTester_Backup.hex":i -U eeprom:r:"TransistorTester_Backup.eep":i

Another option is to use a GUI for AVRDUDE. I recommend AVRDUDESS (http://blog.zakkemble.co.uk/avrdudess-a-gui-for-avrdude/).

I did the backup command as you said (copy paste), but the resulted files seems too small: eeprom 2477 bytes and flash 13 bytes!, wont go any further till you give me some advice please, by the way the fuses as reported by avrdudess are: L 0xF7, H 0xDC, E 0x07, LB 0x3C

thank you in advance.

best regards

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on September 21, 2015, 09:24:10 pm
Is this:

http://www.ebay.com/itm/New-Small-12864-LCD-Transistor-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/171815404897?_trksid=p2046732.c100040.m2060&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140107095009%26meid%3D4bf4a0d9d5fe4256add580abc3381565%26pid%3D100040%26rk%3D1%26rkt%3D4%26sd%3D171815404897 (http://www.ebay.com/itm/New-Small-12864-LCD-Transistor-Capacitance-ESR-Meter-Diode-Triode-MOS-LCR-NPN/171815404897?_trksid=p2046732.c100040.m2060&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140107095009%26meid%3D4bf4a0d9d5fe4256add580abc3381565%26pid%3D100040%26rk%3D1%26rkt%3D4%26sd%3D171815404897)

The same as the item below in terms of functionally?  Just repackaged inside the case?

http://www.aliexpress.com/item/Multi-functional-LCD-Backlight-Transistor-Tester-Diode-Thyristor-Capacitance-ESR-Meter-Tester-LCR-with-Grey-Plastic/32322667293.html (http://www.aliexpress.com/item/Multi-functional-LCD-Backlight-Transistor-Tester-Diode-Thyristor-Capacitance-ESR-Meter-Tester-LCR-with-Grey-Plastic/32322667293.html)

Thanks

@EF, both of these testers use 12864 LCDs, they're both from fish8840, both are on firmware 2.1 mod by wieweitm, i dont know about the dimensions of the lcd of the tester without case but for the tester with case it needs to be 46mmx29mm LxW to fit on the viewing window of the tester, the lcd has no header connectors so the flex cable is directly soldered to the MCU pcb and the display is white chars on black background, both testers have 2 tac switches, the MCU section of both testers basically same, the power section of my tester has unpopulated area and it looks like a dc in jack and lithium battery charging ckt. both runs on 9v batt, il post photos tomorow  :)

papabol_24, Thanks

a few more questions...

Perhaps the LCD is the same size but the case covers part of it?  No problem, but are the graphical displays (for example that show the transistor layouts) the same on the non-case and the cased units?  (Seems like they should be but I haven't seen any detailed photos of the display in a cased unit.)

Also, if they are both running on firmware 2.1 mod by wieweitm why is there so much interest in upgrading the firmware?  (Just to keep current with future changes, or something else?)

Thanks again, EF
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on September 21, 2015, 10:13:37 pm
Hi, I have a couple of these MK-168 devices I bought a long time back...

(http://i.imgur.com/h9ofcgS.jpg)

They both have ATmega168's in sockets. I have 328's I can swap them with.

Without going through 80 pages what would the experts in this device recommend as firmware upgrades for this 2x16 LCD version? for 168 and 328? Also any particular hardware mods for this recommended?  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 22, 2015, 06:28:06 am
Hello EF, as long as its a 12864lcd same ST7565 driver it will render the graphics properly regardless of the lcd size, :) weiweitms 2.1 version for me is very basic compared to the latest firmwares found on this thread for the fish8840, the v1.12k r554 firmware has added features like freq gen, freq counter, contrast adjustment, PWM gen that i didnt find on wieweitms.
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on September 22, 2015, 09:10:01 am
Hello, Photos of both of my testers  :) sorry for late post, im at work  :)


(http://i.imgur.com/OZ3RQ7E.jpg)

(http://i.imgur.com/nPn1orz.jpg)

white tester pcb

(http://i.imgur.com/Zf1uoE7.jpg)

black tester pcb

(http://i.imgur.com/qbwKG7W.jpg)

black tester pcb top view

(http://i.imgur.com/nCqOUBW.jpg)

as you can see both of my testers has unpopulated areas for other ckts compared to this tester by 91make

(http://i.imgur.com/rlaJLDB.jpg)

lcd module dimensions and connector photo

(http://i.imgur.com/RigbTmm.jpg)



Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 22, 2015, 01:53:53 pm
Without going through 80 pages what would the experts in this device recommend as firmware upgrades for this 2x16 LCD version? for 168 and 328? Also any particular hardware mods for this recommended?  :-+

Replacing the 168 with a 328 is a good idea. For the firmware you can choose between the current k and m firmwares. Both are available at http://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/) ("trunk" for the k-firmware, "Markus" for the m-firmware). There's also a docs directory with Karl-Heinz' great documentation including some hints about Chinese clones and recommended hardware changes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 22, 2015, 02:45:57 pm
I did the backup command as you said (copy paste), but the resulted files seems too small: eeprom 2477 bytes and flash 13 bytes!, wont go any further till you give me some advice please, by the way the fuses as reported by avrdudess are: L 0xF7, H 0xDC, E 0x07, LB 0x3C

Content of the MCU is locked.
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 22, 2015, 05:15:32 pm
I did the backup command as you said (copy paste), but the resulted files seems too small: eeprom 2477 bytes and flash 13 bytes!, wont go any further till you give me some advice please, by the way the fuses as reported by avrdudess are: L 0xF7, H 0xDC, E 0x07, LB 0x3C

Content of the MCU is locked.

thank you, there is something i can do?  as i understand backup is not possible, but i can still flash new firmware?


best regards

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on September 22, 2015, 07:33:03 pm
I did the backup command as you said (copy paste), but the resulted files seems too small: eeprom 2477 bytes and flash 13 bytes!, wont go any further till you give me some advice please, by the way the fuses as reported by avrdudess are: L 0xF7, H 0xDC, E 0x07, LB 0x3C

Content of the MCU is locked.

thank you, there is something i can do?  as i understand backup is not possible, but i can still flash new firmware?


best regards

Pio
My '168 was locked. I couldn't make a backup, but I could erase it and flash the new firmware no problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 22, 2015, 07:53:57 pm
I did the backup command as you said (copy paste), but the resulted files seems too small: eeprom 2477 bytes and flash 13 bytes!, wont go any further till you give me some advice please, by the way the fuses as reported by avrdudess are: L 0xF7, H 0xDC, E 0x07, LB 0x3C

Content of the MCU is locked.

thank you, there is something i can do?  as i understand backup is not possible, but i can still flash new firmware?


best regards

Pio
My '168 was locked. I couldn't make a backup, but I could erase it and flash the new firmware no problem.



thank you, you recomend first erase then flash, or the invoved erase in flash procedure is sufficent?


best regards

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on September 22, 2015, 08:05:55 pm
thank you, you recomend first erase then flash, or the invoved erase in flash procedure is sufficent?


best regards

Pio
In order to flash you have to erase the chip, so really that bit is normally done automatically by the programmer. Technically you can flash without erasing the chip but that just results in nonsense merged bits, so just forget that ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 22, 2015, 08:29:20 pm
thank you, you recomend first erase then flash, or the invoved erase in flash procedure is sufficent?


best regards

Pio
In order to flash you have to erase the chip, so really that bit is normally done automatically by the programmer. Technically you can flash without erasing the chip but that just results in nonsense merged bits, so just forget that ;)

thank you,  i will try the firmware Tom666 post for me, hope it works as Tom666 request i will report if it works correctly.

thank you again

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 22, 2015, 09:17:09 pm
just a question, the frequency counter function in firmware 1.12k supports analog signals or just digital?

I think that what is important is the sufficient level of the test signal. For best input sensitivity it is necessary to set the supplement as described in the manual (2.2.4 Frequency measurement).

Works firmware that I uploaded for you in the previous post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg751644/#msg751644)?

i already flashed the firmware you kindly post for me (erase the chip and then flash, the mcu was locked as you said), i wish to report the results: the display is upside down, and a bit displaced to one side, the characters looks incomplete  (maybe because is upside down). the contrast is dim (dont know if the defaults are defined in the makefile ) everything else works as should be.

the attached photo is with the contrast adjusted via the menu.


thank you again.

best regards

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 23, 2015, 08:47:07 am
i already flashed the firmware you kindly post for me (erase the chip and then flash, the mcu was locked as you said), i wish to report the results: the display is upside down, and a bit displaced to one side, the characters looks incomplete  (maybe because is upside down). the contrast is dim (dont know if the defaults are defined in the makefile ) everything else works as should be.

You need to flip x and y in the Makefile and recompile the firmware. The offset you see is 4 pixels. That's caused by the display's controller, which uses 132 columns internally while the LCD only got 128. After flipping x and y the offset should be gone. Otherwise there's also a setting for that offset.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 23, 2015, 04:48:58 pm
yo0,try this firmware for the tester. I hope everything will work!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 23, 2015, 05:01:18 pm
In the last audits of a firmware the author added the new mode of measurement of inductance. It is necessary for operation of this mode in case of calibration (Selftest mode) there will be a parameter "Cap for L meas?" - the condenser for measurement of L.
in case of which it is necessary on T1 - T3 to connect capacity =10nF to 20nF which in case of measurement needs to be connected further parallel to the measured inductivity
In case of measurement on T1 - the inductivity T3 with parallely connected condenser is displayed:
1 - 3  0.02- - resistance in Ohm.
600nH if 10.7nF - inductivity in mH (millihenry) µH (microhenry) of nH (nanohenry) with if capacity added parallely in nF (nanofarad).
1985kHz Q=2.5 - frequency (resonant or the frequency of a circuit) in kHz (kilohertz) and Q (good quality of L).
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 23, 2015, 07:01:48 pm
yo0,try this firmware for the tester. I hope everything will work!

thank you very much!, works as intended, just i having trouble with calibration, as i understand i need a 10-20 nf cap, need to find one :(

and the font you choose looks great!!

you plan to release new versions this model in the future?


best regards

Pio


Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 23, 2015, 07:21:11 pm
yo0, I am glad that at you the firmware earned! :)
You can use for calibration any capacity from 10nF above, it is only desirable that it was high quality.
If fresh firmwares for your clone are necessary, I will help!
I collect and I compile firmwares for different clones, on Yandex resource a disk I have a space for them. You can look at them according to the link
https://yadi.sk/d/yW8xa5NJgUo5z
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 23, 2015, 08:08:22 pm
yo0, I am glad that at you the firmware earned! :)
You can use for calibration any capacity from 10nF above, it is only desirable that it was high quality.
If fresh firmwares for your clone are necessary, I will help!
I collect and I compile firmwares for different clones, on Yandex resource a disk I have a space for them. You can look at them according to the link
https://yadi.sk/d/yW8xa5NJgUo5z

thank you very much again, i already bookmaked your repository, i will visit it for any update.

thank you again!

best regards

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: nbritton on September 24, 2015, 04:53:54 am
Can someone post an executive summary of this 87 page thread? I would like to know how I can build one or where I can pickup one of these devices.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 24, 2015, 05:31:38 am
There are so many to choose from. Some are assembled, some are in kit form.

Here's a high-level summary of some of the variations:


There are many other details, but hopefully this will get you oriented.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on September 24, 2015, 06:51:12 am

Here's a high-level summary of some of the variations:

6. With or without ISP connector.

In the case of non-socketed processors you will need the ISP connector for flashing.

Since I wanted to help development of this thing, I went for the GM 328. It has a socketed processor.
So it is easy to flash externally and replace if damaged. Can easily happen when connecting
large capacitors which are still charged. A protection circuit would prohibit measurements
on other components.

Yours Messtechniker

Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 24, 2015, 06:00:53 pm
Thanks for the additional info, Messtechniker.

I got my kit today (socketed 328 with graphical LCD and rotary switch). Weekend project!
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 28, 2015, 12:40:51 am
hello, somebody know the unpopulated parts of this tester pcb are intended for?


best regards


Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: quantalume on September 28, 2015, 03:27:10 pm
some are socketed DIP (easy to replace if you fry it because you forget to discharge a cap before testing), others are SMD.

This is a very good point. In fact, I would not recommend anyone buy a version without either a socketed controller or protection on the input pins.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 28, 2015, 04:11:25 pm
hello, somebody know the unpopulated parts of this tester pcb are intended for?

yo0, these details are necessary to provide a supply and illumination for displays of different types. If everything works for you, there is no need to solder them
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on September 28, 2015, 10:09:52 pm
hello, somebody know the unpopulated parts of this tester pcb are intended for?

yo0, these details are necessary to provide a supply and illumination for displays of different types. If everything works for you, there is no need to solder them

thank you for the info!


Pio

Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on October 01, 2015, 03:17:44 am
Don't know if this one has been nominated in the tester + frequency generator category:
http://www.amazon.com/gp/product/B00OOQC2E8/ref=pd_luc_rh_top_sim_03_03_t_img_lh?ie=UTF8&psc=1 (http://www.amazon.com/gp/product/B00OOQC2E8/ref=pd_luc_rh_top_sim_03_03_t_img_lh?ie=UTF8&psc=1)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 01, 2015, 07:16:58 am
Don't know if this one has been nominated in the tester + frequency generator category:
http://www.amazon.com/gp/product/B00OOQC2E8/ref=pd_luc_rh_top_sim_03_03_t_img_lh?ie=UTF8&psc=1 (http://www.amazon.com/gp/product/B00OOQC2E8/ref=pd_luc_rh_top_sim_03_03_t_img_lh?ie=UTF8&psc=1)
Any tester with a new firmware from Karl-Heinz Kübbeler contains this function of the generator
Title: Re: $20 LCR ESR Transistor checker project
Post by: wasyoungonce on October 01, 2015, 08:24:06 am
Don't know if this one has been nominated in the tester + frequency generator category:
http://www.amazon.com/gp/product/B00OOQC2E8/ref=pd_luc_rh_top_sim_03_03_t_img_lh?ie=UTF8&psc=1 (http://www.amazon.com/gp/product/B00OOQC2E8/ref=pd_luc_rh_top_sim_03_03_t_img_lh?ie=UTF8&psc=1)

Yeah I have one...from fleabay  works ok but no in circuit programming port.
Here it is.... in a feable box.  Had to remove the display SIL header and lower the display (so it wasn't too high wrt the ZIF socket), butcher the box and heat bend the zif socket actuator arm to fit.

What can I say...it works, no prizes though.


Title: Re: $20 LCR ESR Transistor checker project
Post by: amirtebyan on October 01, 2015, 09:59:45 am
Hi guys:
My english is not very good.

I have some problems with my tester.
I use 1.12k ver with graphic lcd st7920 and atmega2560.

1_ some times When no component connected and i press test key a capacitor in range of micro farad is shown.

2_ When "not calibrated" massage is shown on lcd i do calibration prosses and after finishing it this massage shown again.

3_ when i connect any inductor and press test button lcd dosen't show any thing and i should reset microcontroller for back to normal opration. This happen some times when i connect larg capacitor to tester like 2200 uf .

Do you know the reason?

Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on October 01, 2015, 10:26:05 am
yo0, I am glad that at you the firmware earned! :)
You can use for calibration any capacity from 10nF above, it is only desirable that it was high quality.
If fresh firmwares for your clone are necessary, I will help!
I collect and I compile firmwares for different clones, on Yandex resource a disk I have a space for them. You can look at them according to the link
https://yadi.sk/d/yW8xa5NJgUo5z

with open programming spl7 extension schemes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 01, 2015, 11:42:26 am
with open programming spl7 extension schemes.

Diagrams in the spl7 format open the sPlan7.0 program. Link to this software:
http://abacom-online.de/uk/html/demoversionen.html (http://abacom-online.de/uk/html/demoversionen.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 01, 2015, 12:11:58 pm

1_ some times When no component connected and i press test key a capacitor in range of micro farad is shown.

2_ When "not calibrated" massage is shown on lcd i do calibration prosses and after finishing it this massage shown again.

3_ when i connect any inductor and press test button lcd dosen't show any thing and i should reset microcontroller for back to normal opration. This happen some times when i connect larg capacitor to tester like 2200 uf .


Do you power the tester with a battery or a switching mode power supply?
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on October 01, 2015, 01:16:17 pm
with open programming spl7 extension schemes.

Diagrams in the spl7 format open the sPlan7.0 program. Link to this software:
http://abacom-online.de/uk/html/demoversionen.html (http://abacom-online.de/uk/html/demoversionen.html)

Thank!  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: amirtebyan on October 01, 2015, 01:50:30 pm
Do you power the tester with a battery or a switching mode power supply?

I use switching power supply with 9v 1000mA output.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 01, 2015, 01:59:26 pm
Do you power the tester with a battery or a switching mode power supply?

I use switching power supply with 9v 1000mA output.

Please try a battery or a linear regulated power supply.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amirtebyan on October 01, 2015, 02:13:12 pm
Please try a battery or a linear regulated power supply.

Thanks I will try it.

I have another questions to
1- When I connect capacitors like 2200uF and 100uF are shown  much lower (1.7mF and 79uF). what is the reason?
2- I use atmega2560 and i set clock source 8Mhz internal rc oscillator , is it ok? how should i set the other fuese?


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 01, 2015, 04:01:14 pm
1- When I connect capacitors like 2200uF and 100uF are shown  much lower (1.7mF and 79uF). what is the reason?

I'd think it's caused by normal tolerances.

Quote
2- I use atmega2560 and i set clock source 8Mhz internal rc oscillator , is it ok? how should i set the other fuese?

For a higher accuracy I'd recommend an external crystal. The fuse settings are in the setup.mk file (included by Makefile).
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on October 02, 2015, 12:09:38 am
1- When I connect capacitors like 2200uF and 100uF are shown  much lower (1.7mF and 79uF). what is the reason?

Check what's the tolerance for those capacitors. For example, if they're 10%, then the 2200uF can be from 1980-2420uF (2200+-220uF). Looks like those two are a little over 20%, which might be close enough for 20% caps if your tester is a little out of calibration.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on October 02, 2015, 03:46:05 pm
Questions about the rotary encoder option:

I've got the simple 2 line, through-hole version of the tester, with an ATmega328P:
http://www.ebay.com/itm/M328-Transistor-Tester-Capacitor-ESR-Inductance-Resistor-LCR-Meter-NPN-PNP-MOS/281538451480 (http://www.ebay.com/itm/M328-Transistor-Tester-Capacitor-ESR-Inductance-Resistor-LCR-Meter-NPN-PNP-MOS/281538451480)
It came with firmware v1.11k but I compiled and installed v1.18m, which I think I like better.

I'm planning to replace the test switch with a rotary encoder. However, examining the documents and schematics shows that, by default, the k firmware uses PD1 and PD3 for the encoder signals whereas the m firmware uses PD2 and PD3. I haven't determined if the phase on PD3 matches.

Is there a good reason for this difference or is it just that the code was developed independently?

Would there be any problem if I change "#define ENCODER_A PD2" to "#define ENCODER_A PD1" in the m firmware's config.h file and then recompile?

There are now versions of the tester being sold with a rotary encoder as standard. On these units, which processor pins are used, and which is assigned phase A and phase B?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 02, 2015, 04:27:50 pm
It came with firmware v1.11k but I compiled and installed v1.18m, which I think I like better.

I'm planning to replace the test switch with a rotary encoder. However, examining the documents and schematics shows that, by default, the k firmware uses PD1 and PD3 for the encoder signals whereas the m firmware uses PD2 and PD3. I haven't determined if the phase on PD3 matches.

Is there a good reason for this difference or is it just that the code was developed independently?

Would there be any problem if I change "#define ENCODER_A PD2" to "#define ENCODER_A PD1" in the m firmware's config.h file and then recompile?

There are now versions of the tester being sold with a rotary encoder as standard. On these units, which processor pins are used, and which is assigned phase A and phase B?

In an older k-firmware version the default I/O pins used for the rotary encoder were also PD2/PD3 and were changed to PD1/PD3 later on. The m-firmware has kept the original I/O pins. Of course you can change the I/O pins in config.h as long as they belong to the same port. I got no idea about the A/B pinout of the Chinese clones. In case it's reversed, simply reverse the I/O pins config.h, problem solved ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on October 02, 2015, 06:15:13 pm
Of cource you can change the I/O pins in config.h as long as they belong to the same port.
OK, thanks.

Quote
I got no idea about the A/B pinout of the Chinese clones. In case it's reversed, simply reverse the I/O pins config.h, problem solved ;)
I only asked this because if it turns out there is a consistent way that these clones are being wired, I may as well wire mine the same.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 02, 2015, 09:51:07 pm
As I prepare to assemble one of these from a kit with a plastic housing, it occurs to me that it might be useful to have an easy way to store and switch between separate sets of calibration data; one set for use with the ZIF socket, the other for use with test leads.

Does this sound useful to anyone else? Is anyone aware of a patch that already does this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on October 02, 2015, 10:44:46 pm
it occurs to me that it might be useful to have an easy way to store and switch between separate sets of calibration data; one set for use with the ZIF socket, the other for use with test leads.

The m-firmware only stores one set of calibration data but you can temporarily re-calibrate without the new data being saved after power off (unless you want override the previous data and save the new).

So you could save calibration data for the ZIF socket and when you wanted to use the test leads, short them out and do a temporary calibration.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2015, 11:59:55 am
As I prepare to assemble one of these from a kit with a plastic housing, it occurs to me that it might be useful to have an easy way to store and switch between separate sets of calibration data; one set for use with the ZIF socket, the other for use with test leads.

Does this sound useful to anyone else? Is anyone aware of a patch that already does this?

I think it's a nice idea and will put it on my to-do list.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 03, 2015, 05:29:54 pm
As I prepare to assemble one of these from a kit with a plastic housing, it occurs to me that it might be useful to have an easy way to store and switch between separate sets of calibration data; one set for use with the ZIF socket, the other for use with test leads.

Does this sound useful to anyone else? Is anyone aware of a patch that already does this?

I think it's a nice idea and will put it on my to-do list.
Cool, thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on October 08, 2015, 10:14:41 pm
I wired up a rotary encoder to my tester. I then tried to compile v1.18m firmware with the rotary encoder option (HW_ENCODER) but without the frequency counter option (HW_FREQ_COUNTER). When I executed make I got the following error:
Code: [Select]
extras.c: In function ‘SquareWave_SignalGenerator’:
extras.c:335:34: error: ‘T1_Prescaler_table’ undeclared (first use in this function)
       Prescaler = MEM_read_word(&T1_Prescaler_table[Index]);
                                  ^

After investigating the problem, I think it's due to the following code segments in variables.h:
Code: [Select]
  #if defined (HW_FREQ_COUNTER) || defined (SW_SIGNAL_GEN)
    /* Timer1 prescalers and corresponding bitmasks */
    const uint16_t T1_Prescaler_table[] MEM_TEXT = {1, 8, 64, 256, 1024};
    const uint8_t T1_Bitmask_table[] MEM_TEXT = {(1 << CS10), (1 << CS11), (1 << CS11) | (1 << CS10), (1 << CS12), (1 << CS12) | (1 << CS10)};
  #endif

Code: [Select]
  #if defined (HW_FREQ_COUNTER) || defined (SW_SIGNAL_GEN)
    /* Timer1 prescalers and corresponding bitmasks */
    extern const uint16_t T1_Prescaler_table[];
    extern const uint8_t T1_Bitmask_table[];
  #endif

Since HW_FREQ_COUNTER is not defined, then SW_SIGNAL_GEN needs to be defined in order to create the tables. However, there is no mention of SW_SIGNAL_GEN anywhere else in the code. I believe the two instances of SW_SIGNAL_GEN should be changed to SW_SQUAREWAVE. When I made these changes the code compiled without errors and my tester appears to be functioning properly with it.

P.S. If there's somewhere other than this thread where it would be more appropriate to submit bug reports and discuss software issues, please let me know.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on October 09, 2015, 04:54:21 am

P.S. If there's somewhere other than this thread where it would be more appropriate to submit bug reports and discuss software issues, please let me know.


A good place is:
https://www.mikrocontroller.net/topic/248078?page=8 (https://www.mikrocontroller.net/topic/248078?page=8)
Its a veeeeeeeeeeeery long thread mostly in German but also with some English and
Karl-Heinz Kübbeler (kubi48) is your man (who works very hard on
the firmware of this thing).

Yours Messtechniker
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 09, 2015, 06:25:26 am
If there's somewhere other than this thread where it would be more appropriate to submit bug reports and discuss software issues, please let me know.

You should probably get an answer in this thread, because the author of the m-version of the software is user "madires (https://www.eevblog.com/forum/profile/?u=25360)".
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 09, 2015, 12:17:34 pm
I wired up a rotary encoder to my tester. I then tried to compile v1.18m firmware with the rotary encoder option (HW_ENCODER) but without the frequency counter option (HW_FREQ_COUNTER). When I executed make I got the following error:
Code: [Select]
extras.c: In function ‘SquareWave_SignalGenerator’:
extras.c:335:34: error: ‘T1_Prescaler_table’ undeclared (first use in this function)
       Prescaler = MEM_read_word(&T1_Prescaler_table[Index]);
                                  ^

Since HW_FREQ_COUNTER is not defined, then SW_SIGNAL_GEN needs to be defined in order to create the tables. However, there is no mention of SW_SIGNAL_GEN anywhere else in the code. I believe the two instances of SW_SIGNAL_GEN should be changed to SW_SQUAREWAVE. When I made these changes the code compiled without errors and my tester appears to be functioning properly with it.

Yes, that's an error. It should be
Code: [Select]
  #if defined (HW_FREQ_COUNTER) || defined (SW_SQUAREWAVE)
in variables.h. It's already fixed in both v1.19m editions (not released yet). BTW, I'm the right person to send bug reports to, regarding the m-firmware  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 09, 2015, 12:51:52 pm
A good place is:
https://www.mikrocontroller.net/topic/248078?page=8 (https://www.mikrocontroller.net/topic/248078?page=8)
Its a veeeeeeeeeeeery long thread mostly in German but also with some English and
Karl-Heinz Kübbeler (kubi48) is your man (who works very hard on
the firmware of this thing).

... in case of the k-firmware. But we both forward bug reports and what have you to each other.

Some updates about the upcoming v1.19m:
- bug fixes
- updated Czech texts (thanks to Kapa)
- display driver for ILI9341/ILI9342 (trendy edition)
- performance improvements for graphic LCDs (trendy edition)
  A 320x240 ILI9341 is quite restrained when driven via bit-bang SPI, but a 16MHz crystal helps a little bit ;)

I've planned to add the fancy pinout in this release too but had/have to deal with a bereavement, a broken heart and a flu. Why do bad things happen all at once? So I ask you all if I should release v1.19m soon without the fancy pinout or if you are patient to wait another month or so?
Title: Re: $20 LCR ESR Transistor checker project
Post by: onlooker on October 09, 2015, 12:58:49 pm
I am toying one of such thing. What should be the correct way to detect a bjt with internal diode between C-E such as 13003?

Apparently, mine will display both PNP and NPN depending on the way the bjt is seated in the lock socket and either way showed a sensible hfe about 15.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 09, 2015, 01:43:42 pm
I am toying one of such thing. What should be the correct way to detect a bjt with internal diode between C-E such as 13003?

Apparently, mine will display both PNP and NPN depending on the way the bjt is seated in the lock socket and either way showed a sensible hfe about 15.

Which firmware (k or m) and which version do you run?
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on October 09, 2015, 01:46:43 pm
So I ask you all if I should release v1.19m soon without the fancy pinout or if you are patient to wait another month or so?

It depends if any of the "bug fixes" are important.

Since my tester only has a 2x16 character display and thus uses the classic firmware compiled for English, none of the enhancements you mentioned seems to be of any concern to me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 10, 2015, 10:41:10 am
One little enhancement (because it's not really a bug fix) I've been waiting for is the symbol for hfe shown as Greek beta rather than B. This can be configurable in case a certain display has something else in that position, but the cheapest of the Chinese English displays have it at 226 (decimal). Been editing Transistortester.h for a long time to do this.

I've planned to add the fancy pinout in this release too but had/have to deal with a bereavement, a broken heart and a flu. Why do bad things happen all at once? So I ask you all if I should release v1.19m soon without the fancy pinout or if you are patient to wait another month or so?

Work may be able to help with the other two, but the flu? Health is more important. I'm sure waiting a few weeks for a new release won't hurt anyone. Not as much as complications from the flu can, anyway. Get well soon!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 10, 2015, 11:53:46 am
It depends if any of the "bug fixes" are important.

Since my tester only has a 2x16 character display and thus uses the classic firmware compiled for English, none of the enhancements you mentioned seems to be of any concern to me.

I got following for the classic edition so far:
- Updated Czech texts, thanks to Kapa.
- Fixed variable management bug in config.h.
- Optimized functions for NVRAM management (values stored in EEPROM).

#2 is the error you've spotted.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 10, 2015, 11:58:39 am
One little enhancement (because it's not really a bug fix) I've been waiting for is the symbol for hfe shown as Greek beta rather than B. This can be configurable in case a certain display has something else in that position, but the cheapest of the Chinese English displays have it at 226 (decimal). Been editing Transistortester.h for a long time to do this.

That seems to be the k-firmware. I've forwarded your suggestion to Karl-Heinz.

Quote
Work may be able to help with the other two, but the flu? Health is more important. I'm sure waiting a few weeks for a new release won't hurt anyone. Not as much as complications from the flu can, anyway. Get well soon!

Thanks! Work helps, indeed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 10, 2015, 10:21:53 pm
One little enhancement (because it's not really a bug fix) I've been waiting for is the symbol for hfe shown as Greek beta rather than B. This can be configurable in case a certain display has something else in that position, but the cheapest of the Chinese English displays have it at 226 (decimal). Been editing Transistortester.h for a long time to do this.

That seems to be the k-firmware. I've forwarded your suggestion to Karl-Heinz.

You're right, sorry for the confusion. I use both versions and sometimes I'm thinking of one while talking about the other. Thanks for forwarding it! I should have also included that I think an asterisk looks worse than an x for displaying the "times" symbol...

I've got one for you, too though.  :P When the tester shows that it detected multiple diodes (like 4), the message preceding that says that no component is found. That's rather contradictory: It knows that something is connected, yet says otherwise.
Title: Re: $20 LCR ESR Transistor checker project
Post by: onlooker on October 11, 2015, 12:06:29 am
I am toying one of such thing. What should be the correct way to detect a bjt with internal diode between C-E such as 13003?

Apparently, mine will display both PNP and NPN depending on the way the bjt is seated in the lock socket and either way showed a sensible hfe about 15.

Which firmware (k or m) and which version do you run?

Thanks for replying. I bought mine recently from Ebay due to this thread. But, I may have missed some info here or missed the level of relevance since I only read a very small part of this long thread.

By the seller, my tester is:

Quote
1. 2013 latest M328 version of the software ,more functions.Chip: Atmega328.
2. 128*64 big Backlight LCD display,only 2mA when stand by.

When starting up,  it shows "MTester v2.07...by Efan &Haoqixin"
Title: Re: $20 LCR ESR Transistor checker project
Post by: ralphd on October 11, 2015, 12:09:55 am
A good place is:
https://www.mikrocontroller.net/topic/248078?page=8 (https://www.mikrocontroller.net/topic/248078?page=8)
Its a veeeeeeeeeeeery long thread mostly in German but also with some English and
Karl-Heinz Kübbeler (kubi48) is your man (who works very hard on
the firmware of this thing).

... in case of the k-firmware. But we both forward bug reports and what have you to each other.

Some updates about the upcoming v1.19m:
- bug fixes
- updated Czech texts (thanks to Kapa)
- display driver for ILI9341/ILI9342 (trendy edition)
- performance improvements for graphic LCDs (trendy edition)
  A 320x240 ILI9341 is quite restrained when driven via bit-bang SPI, but a 16MHz crystal helps a little bit ;)

I've planned to add the fancy pinout in this release too but had/have to deal with a bereavement, a broken heart and a flu. Why do bad things happen all at once? So I ask you all if I should release v1.19m soon without the fancy pinout or if you are patient to wait another month or so?
You could use my asm SPI code.
http://nerdralph.blogspot.ca/2015/03/fastest-avr-software-spi-in-west.html (http://nerdralph.blogspot.ca/2015/03/fastest-avr-software-spi-in-west.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ralphd on October 11, 2015, 01:46:48 am
The BOM is about $3 with the 1602 LCD and atmega328 accounting for $2.5 of that.  Strangely I can't find them for less than $10.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 11, 2015, 04:38:40 am
The BOM is about $3 with the 1602 LCD and atmega328 accounting for $2.5 of that.  Strangely I can't find them for less than $10.
Um, why do you expect to?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ralphd on October 11, 2015, 06:38:42 am
The BOM is about $3 with the 1602 LCD and atmega328 accounting for $2.5 of that.  Strangely I can't find them for less than $10.
Um, why do you expect to?
Because things like Pro Minis sell for about 25% over their BOM cost.

http://m.aliexpress.com/item/32229454220.html (http://m.aliexpress.com/item/32229454220.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 11, 2015, 08:12:42 am
Less specialized / more general -> higher volume -> better economies of scale / more competition -> lower margins
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on October 11, 2015, 11:59:57 am
No, it not a separate tester. The basic firmware from Karl-Heinz Kübbeler with function of measurement of voltage reference diodes is used. Changes are made only in the tester hardware  :D

Well then. I guess I was almost completely wrong. How extensive are the hardware changes? Is this fork being made available in the same way as the original Karl-Heinz transistor tester?

Hi indiman!

About your "fork" and  explain more detailed your modifications

I'm  very interested on your modification, thanks a lot!

You can use your native language if others could translate it. Please, it would be greatly
* Can you say what's your native language?

- Some suggestions:
* How it measures 78xx and other voltage/current ICs, procedure and limitations.
* Manufacturing considerations: Layout, interferences, recommended shielding, connectors, other advices.



About possible future additions and improvements

- Are there possibilities of having a better firmware integration?
- Can other features be added easily without going into feature creep? 74xx and 40xx testing like in minipro, for example.

My reasons to build this device and contribute by making it in KiCad


I have and use TONS of salvaged parts

- A device like this might be really useful to check salvaged parts.
- It would save me time at the end.

I'm a cursed idealist, unable to change that. I'm a unadaptable person by nature.

- I'm an extreme copyleft believer:
* FOSS, OSHW and Open Access are just parts of it. I want to promote it very actively in every place.


Suggestion: Making your improved design a collaborative OSHW project and using KiCad (FOSS)

- Do you use KiCad? What about sharing schematics over GitHub? ;)
* I could try to recreate your design in KiCad, submit it at GitHub and ask others about bugs and improvements. I'm awful at EDA, so please be polite and constructive ;)

- Would you consider switching to KiCad 4 RC1/RC2/nightly?
* Maybe someone could help you by translating it to your native language. I'm doing to translate it to Spanish by using Transifex.com (very easy).

Other reasons: I have ADHD, economical issues, etc. (https://www.eevblog.com/forum/index.php?topic=46204.0)

-----
About language

Can you say us where are you from and what's your native language?

- The first part is optional, but you are free to say it it but depending on your situation.
- I'm from Spain, so Spanish.

Maybe some of us could assist you with communication and even help you at English:

- My English is very far from perfect:
* I consider to have very good English reading skills.
* I think to have enough good written English skills if not writing it too fast or very tired.
* My speaking English is awful, but slowly improving.

I emphasize with you a lot. I had the same problem when starting to use Linux in the early 2000:
- I did my first hard baby steps when Linux kernel and other software needed to be compiled by hand (configure && make && make install):
* There weren't nice source based package repositories and sometimes you needed to use bleeding edge software for certain functionalities. * Debian was a mess at packages, Red Hat okaish but had issues too.
- I had lots issues but that ironically made it a funny challenge.
- I asked my issues over IRC by using online translators and dictionaries, but I was lots jess skilled than you:
* Fortunately some Mexican people helped me to explain my issues to others and act as interpreters.
* Despite my lack of proper formal English learning because school was awfully bad at teaching it and I hated to assist, I improved by practice.

- These days I use Archlinux and Linux Mint. I'm considering to switch back to Gentoo or similar, i just need to realize a twisted plan and get new hardware:
* I liked the extreme configurability of ebuilds.
* I need to consider the viability to use remote hardware to accelerate compiling.


Kind regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2015, 12:13:57 pm
I've got one for you, too though.  :P When the tester shows that it detected multiple diodes (like 4), the message preceding that says that no component is found. That's rather contradictory: It knows that something is connected, yet says otherwise.

The original idea was to give a hint about possible diodes when no component was identified. Since the output of the pinout for more than 2 diodes would be a nightmare, the Show_Fail() function is simply used for that too, to save a few bytes flash memory. I'll look into it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2015, 12:17:43 pm
When starting up,  it shows "MTester v2.07...by Efan &Haoqixin"

Sorry, that's a modified firmware. You have to ask the seller for a current one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2015, 12:21:34 pm
You could use my asm SPI code.
http://nerdralph.blogspot.ca/2015/03/fastest-avr-software-spi-in-west.html (http://nerdralph.blogspot.ca/2015/03/fastest-avr-software-spi-in-west.html)

I'll have a look. Thanks for the hint!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 11, 2015, 04:36:03 pm

Do you use KiCad? If so, what about sharing schematics over GitHub? ;)

What's your language? Maybe some of us could assist you with communication. I'm from Spain.


No, I use for drawing of electric circuits and design of printed circuit boards of the program from ABACOM (SPLan 7.0 and Sprint-Layout 6.0). Link to this software:
http://abacom-online.de/uk/html/demoversionen.html (http://abacom-online.de/uk/html/demoversionen.html)
What specifically interests you according to this diagram? I will try to answer questions. My native language Russian! :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kalvin on October 11, 2015, 04:48:09 pm
Would there be any idea to add another Atmega328p to be used as an LCD driver? That would leave more room for the actual measurement application in the main Atmega328p. The two processors would communicate over SPI bus, and the SPI bus could be unidirectional thus making things quite simple. The BOM would not suffer too much either. Not sure how much this would complicate the actual code, though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on October 11, 2015, 05:22:01 pm

Do you use KiCad? If so, what about sharing schematics over GitHub? ;)

What's your language? Maybe some of us could assist you with communication. I'm from Spain.


No, I use for drawing of electric circuits and design of printed circuit boards of the program from ABACOM (SPLan 7.0 and Sprint-Layout 6.0). Link to this software:
http://abacom-online.de/uk/html/demoversionen.html (http://abacom-online.de/uk/html/demoversionen.html)
What specifically interests you according to this diagram? I will try to answer questions. My native language Russian! :D

I modified the post after you replied, sorry.

Another smart Russian guy. Nice!

sPlan is proprietary and for Windows. I want to use KiCad. I'm a very long time Linux user.

Can you export the project in some compatible formats please? Netlist, IDF, DXF.

Is the PCB routing so hard to make? I might try to do the export with and ask for help out there.

Are you brave enough to try latest KiCad too? ;)

Kind regards!

PS: To all the involved parties in this project: Would you accept some good
Spanish food as donation? Wine or others. Send PM! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2015, 06:57:04 pm
Would there be any idea to add another Atmega328p to be used as an LCD driver? That would leave more room for the actual measurement application in the main Atmega328p. The two processors would communicate over SPI bus, and the SPI bus could be unidirectional thus making things quite simple. The BOM would not suffer too much either. Not sure how much this would complicate the actual code, though.

That wouldn't solve the problem, because we still would have to use a bit-bang SPI to interface the display. With an ATmega 644 or 1284 there are more I/O pins which could be used for the test resistors to free up the hardware SPI, which in turn could be used to drive the graphic LCD. The 644 example in Karl-Heinz' documentation does exactly that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kalvin on October 11, 2015, 07:32:43 pm
Would there be any idea to add another Atmega328p to be used as an LCD driver? That would leave more room for the actual measurement application in the main Atmega328p. The two processors would communicate over SPI bus, and the SPI bus could be unidirectional thus making things quite simple. The BOM would not suffer too much either. Not sure how much this would complicate the actual code, though.

That wouldn't solve the problem, because we still would have to use a bit-bang SPI to interface the display. With an ATmega 644 or 1284 there are more I/O pins which could be used for the test resistors to free up the hardware SPI, which in turn could be used to drive the graphic LCD. The 644 example in Karl-Heinz' documentation does exactly that.

Maybe I expressed my intention a bit poorly. I will try to be more specific this time.

The would be two Atmega328's:

1. The main Atmega328 "Main MCU" running the measurement application without actual display code.
2. The display controller Atmega328 "Display MCU" driving the LCD (or whatever display).

- There is a simple, unidirectional serial bus from the Main MCU to the Display MCU.
- The Main CPU will be a master, and the Display MCU will be a slave.
- There are specific, simple messages passed from the Main MCU to the Dispaly MCU.

    For example, the message might contain following information:
        - Component test
        - Transistor
        - Pin 1 E
        - Pin 2 B
        - Pin 3 C
        - NPN
        - Gain=200
        -etc.

Thus, the Main MCU will just send simple messages to the Display MCU, and the Display MCU
application will decide how to display that information. This would free quite a lot of code memory
from the Main MCU for the measurement and extra algorithms. The Display MCU would contain all
code displaying the measurement information, fonts, graphical bitmaps and language data.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on October 11, 2015, 07:34:14 pm
Would there be any idea to add another Atmega328p to be used as an LCD driver? That would leave more room for the actual measurement application in the main Atmega328p. The two processors would communicate over SPI bus, and the SPI bus could be unidirectional thus making things quite simple. The BOM would not suffer too much either. Not sure how much this would complicate the actual code, though.

That wouldn't solve the problem, because we still would have to use a bit-bang SPI to interface the display. With an ATmega 644 or 1284 there are more I/O pins which could be used for the test resistors to free up the hardware SPI, which in turn could be used to drive the graphic LCD. The 644 example in Karl-Heinz' documentation does exactly that.

Why not go MIPS or ARM? Or it would overcomplicate, more expensive and require rewriting code?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2015, 07:46:15 pm
Why not go MIPS or ARM? Or it would overcomplicate, more expensive and require rewriting code?

The ATmegas run with 5V which is the ideal voltage for testing components. 3.3V is simply too low, i.e. we would have to add external switching for a higher voltage, external ADC and so on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 11, 2015, 08:19:50 pm
@Circuiteromalaguito, Kalvin, et al:

This, of course, is just my opinion, but...

Every now and then someone comes who wants to add lots of bells and whistles to the existing schematic. The charm of the original tester was in the simplicity of its hardware. Take that away, and you are left with something other than the transistor tester that we are all discussing in this thread. Sure, you can do everything that you suggest, but what reason is there not to do it as a separate project? Then you can use, say, ARM and a voltage converter, and do many other interesting things... but I believe you're trying to horseshoe this particular project into something that it's not.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on October 12, 2015, 06:07:53 am
You could use my asm SPI code.
http://nerdralph.blogspot.ca/2015/03/fastest-avr-software-spi-in-west.html (http://nerdralph.blogspot.ca/2015/03/fastest-avr-software-spi-in-west.html)

Very nice, thanks for info. Assembly was one of my favorite classes when I was in school but I haven't hardly touched it since.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on October 12, 2015, 06:55:42 am
@Circuiteromalaguito, Kalvin, et al:

This, of course, is just my opinion, but...

Every now and then someone comes who wants to add lots of bells and whistles to the existing schematic. The charm of the original tester was in the simplicity of its hardware. Take that away, and you are left with something other than the transistor tester that we are all discussing in this thread. Sure, you can do everything that you suggest, but what reason is there not to do it as a separate project? Then you can use, say, ARM and a voltage converter, and do many other interesting things... but I believe you're trying to horseshoe this particular project into something that it's not.

Fully agree with this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 12, 2015, 07:50:47 am
@hapless:
I agree :-+ I have the same opinion.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on October 12, 2015, 10:38:25 am
I partially disagree.

If the addons are simple enough and provide extra features... Why not?

If you like it simpler, just fork. If you want more features, fork. The most popular fork wins: Open Source evolutionary way ;)

I have over 500x 74xx 40xx 45xx ICs tó test, some of them unlabeled.

I just found devices like this one but with IC TTL CMOS support too.

http://www.ebay.com/bhp/ic-tester
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 12, 2015, 01:08:59 pm
I have over 500x 74xx 40xx 45xx ICs tó test, some of them unlabeled.

I just found devices like this one but with IC TTL CMOS support too.

http://www.ebay.com/bhp/ic-tester (http://www.ebay.com/bhp/ic-tester)

A tester for logic gates is a complete different story. Some universal programmers can do that too but the Transistor Tester won't support that. My opinion about future developments is that we'll keep the simple 328 Transistor Tester as a basic version (inexpensive and easy to build) and add new options/features to a 644/1284 advanced version (more flash, RAM and I/O pins). And I'd like to keep maintaining the code feasable.
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on October 12, 2015, 01:15:00 pm
It shouldn't be the "eierlegende Wollmichsau", I like it for it's simplicity. When I was starting out in electronics, I could build a useful tool with the things I had in hand and learn something in the process. Cramming it with features would make it too complicated for beginners and make it actually less useful. The free hardware point was valid. If you want something more powerful based on the original software, nothing is stopping you from building it.

The only thing I think that is a bit overdue is a new reference design for the board that is well tested and maybe incorporates some of the more useful add-ons such as the rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnatGoSplat on October 12, 2015, 07:47:25 pm
I have a Chinese tester from 2012 with the 2x16 display and an Atmega8L and no crystal.  Figured I'd goof around with it because I can't leave well enough alone.  Mine has no programming pins on the board, but the chip is socketed.  I downloaded the newest firmware (1.12k) that says it works with the Atmega8, and used a TL866 to flash TransistorTester.hex into CODE and TransistorTester.eep into DATA.  It boots up, displays "Version 1.12k", but doesn't detect devices and after awhile of "Testing..." it goes to "Timeout!"  I had backed up the original firmware, so I wrote those back in and all is well again on the original firmware, but what did I do wrong with flashing 1.12k?  I have a hunch I need to change some fuses to tell the software the configuration of my hardware, but I'm not familiar with microcontroller programming and I don't know how to translate the hex codes I see for fuses into the named checkboxes on the TL866 fuse setting screen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on October 12, 2015, 09:07:02 pm
The checkboxes you tick in the TL866 Miniprog settings are all representative of binary bits which all add up to a hex nibble (0-F), byte (00-FF), or word (0000-FFFF)... I don't have mine in front of me but I recall when you tick the checkboxes the combined value in bytes is also displayed. So if you have been told to set the fuses to a certain 0xFF or whatever take a look for that, or just add up the bits 1 2 4 8 16 32 ... etc
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on October 13, 2015, 04:22:02 am
I have over 500x 74xx 40xx 45xx ICs tó test, some of them unlabeled.

I just found devices like this one but with IC TTL CMOS support too.

http://www.ebay.com/bhp/ic-tester (http://www.ebay.com/bhp/ic-tester)

A tester for logic gates is a complete different story. Some universal programmers can do that too but the Transistor Tester won't support that. My opinion about future developments is that we'll keep the simple 328 Transistor Tester as a basic version (inexpensive and easy to build) and add new options/features to a 644/1284 advanced version (more flash, RAM and I/O pins). And I'd like to keep maintaining the code feasable.


Are there plans for a 1284 version?

Are there some standalone 74xx 45xx 40xx checker using a similar hardware? I did see one for PIC published on EPE.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 13, 2015, 06:33:15 am
I have a hunch I need to change some fuses to tell the software the configuration of my hardware, but I'm not familiar with microcontroller programming and I don't know how to translate the hex codes I see for fuses into the named checkboxes on the TL866 fuse setting screen.

Program the tester from fuses, as on the picture below. They for the internal generator of the chip on 8MHz. IntelHex need to load the TransistorTester.eep file in DataMemory as.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 13, 2015, 07:49:22 am
I have a Chinese tester from 2012 with the 2x16 display and an Atmega8L and no crystal. ... I have a hunch I need to change some fuses to tell the software the configuration of my hardware, but I'm not familiar with microcontroller programming and I don't know how to translate the hex codes I see for fuses into the named checkboxes on the TL866 fuse setting screen.

Hi GnatGoSplat,
the recommended setting of the fuses for ATmega8 (Int. RC 8MHz) by software author (KHK) is:
lfuse:0x24 hfuse:0xd9

Bye
Tomas
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 13, 2015, 09:51:11 am
The only thing I think that is a bit overdue is a new reference design for the board that is well tested and maybe incorporates some of the more useful add-ons such as the rotary encoder.

A forum member has planned to create a nice PCB with all hardware options included. So I haven't looked into a new reference PCB yet. Meanwhile there's a simple adapter in the SVN for the rotary encoder and the frequency counter which is inserted between the PCB and the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 13, 2015, 10:00:05 am
Are there plans for a 1284 version?

Please see Karl-Heinz' current documentation ;) There's a circuit for the 644/1284.

Quote
Are there some standalone 74xx 45xx 40xx checker using a similar hardware? I did see one for PIC published on EPE.

I've seen some on ebay, but they seem all to have the same basic design. I got no idea if those are PIC or ATmega.
Title: Re: $20 LCR ESR Transistor checker project
Post by: djQUAN on October 13, 2015, 05:14:02 pm
I bought this a few months back and works well (didn't come with the li ion cell) and just stumbled upon this thread. Still back reading now at P24.

Works pretty well. I chose this over the large LCD types as I can replace the LCD if necessary.
Usb charging with onboard 14500 li ion cell
Uses the 328 uC 1.11k FW and a TL431 voltage reference with an option for trimming but not used.

There appears to be a 6p inline ISP header but I currently don't have an AVR programmer so I'm sticking with the old FW for now.

edit: menu is enabled in mine so the additional functions can be used
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kalvin on October 13, 2015, 07:47:08 pm
@Circuiteromalaguito, Kalvin, et al:

This, of course, is just my opinion, but...

Every now and then someone comes who wants to add lots of bells and whistles to the existing schematic. The charm of the original tester was in the simplicity of its hardware. Take that away, and you are left with something other than the transistor tester that we are all discussing in this thread. Sure, you can do everything that you suggest, but what reason is there not to do it as a separate project? Then you can use, say, ARM and a voltage converter, and do many other interesting things... but I believe you're trying to horseshoe this particular project into something that it's not.

I am great admirer of the minimalist design. No need to make things too complicated. And if the 1284-based version is available, then my suggestion is obsolete of course.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ralphd on October 14, 2015, 01:58:14 am
You could use my asm SPI code.
http://nerdralph.blogspot.ca/2015/03/fastest-avr-software-spi-in-west.html (http://nerdralph.blogspot.ca/2015/03/fastest-avr-software-spi-in-west.html)

I'll have a look. Thanks for the hint!
If your firmware has serial output on PC3, my soft uart is the smallest around, and the only one with no jitter (difference between the timing of 1 vs 0 bits)
https://github.com/nerdralph/nerdralph/tree/master/avr/libs/bbuart
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on October 14, 2015, 06:56:40 am
You could use my asm SPI code.
http://nerdralph.blogspot.ca/2015/03/fastest-avr-software-spi-in-west.html (http://nerdralph.blogspot.ca/2015/03/fastest-avr-software-spi-in-west.html)

I'll have a look. Thanks for the hint!
If your firmware has serial output on PC3, my soft uart is the smallest around, and the only one with no jitter (difference between the timing of 1 vs 0 bits)
https://github.com/nerdralph/nerdralph/tree/master/avr/libs/bbuart (https://github.com/nerdralph/nerdralph/tree/master/avr/libs/bbuart)
You've developed some pretty cool stuff. That soft UART is something I could use on a tiny85  :-+ Bookmarked
Title: Re: $20 LCR ESR Transistor checker project
Post by: djQUAN on October 14, 2015, 09:39:26 am
After reading stuff around here, a good reference is said to be beneficial so I checked my unit.

It was using a TL431 which measured 4.9xx volts on the Vref pin. Swapped it out for a LM336-2.5 and added a trimmer on the unpopulated space so I could set it to exactly 2.500V.

Redid a self cal test and I'm not sure which measurements it helped. But it still worked. Oh well  :phew:
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnatGoSplat on October 14, 2015, 03:16:15 pm
Macbeth, indman, and tom666, thanks very much for the help, it makes sense now and I got it going.

Hi GnatGoSplat,
the recommended setting of the fuses for ATmega8 (Int. RC 8MHz) by software author (KHK) is:
lfuse:0x24 hfuse:0xd9

I used the firmware you attached and also set the fuses exactly as shown.  It now seems to work perfectly with one slight issue is the display of the result goes away very quickly before it shuts off.  Is there a way to increase this delay?
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on October 14, 2015, 03:51:17 pm
In case it's of use to anyone, here are some photos of how I replaced the test switch with a rotary encoder on my tester.

My unit is one of the popular 2 x 16 character display designs with through-hole components and a socketed 328p processor. The board is marked EZM Electronics Studio, M328_9V_V3.1, 2013.09.25

I removed the original test switch, drilled holes and cut lands out of the ground plane. The resistors are size 0603. I also rotated the LED and moved the + terminal so it would be further from the encoder and visible when I added a 20mm knob.

The orange capacitors on the processor pins aren't part of the encoder circuit. They are the recommended 1nF capacitor on AREF, plus additional 100nF capacitors on Vcc and AVcc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 14, 2015, 04:16:48 pm
I used the firmware you attached and also set the fuses exactly as shown.  It now seems to work perfectly with one slight issue is the display of the result goes away very quickly before it shuts off.  Is there a way to increase this delay?

Delays can be adjusted by modifying the file "config.h".

It is this part of the code (the time is specified in milliseconds):
// LONG_WAIT_TIME is the time for displaying the successfull test result
#ifndef LONG_WAIT_TIME
#define LONG_WAIT_TIME 28000
#endif

// MIDDLE_WAIT_TIME is used for display the next parameter for Show data menu function
#define MIDDLE_WAIT_TIME 15000

// SHORT_WAIT_TIME is the time for displaying a unknown component message
#ifndef SHORT_WAIT_TIME
#define SHORT_WAIT_TIME 8000
#endif
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 14, 2015, 05:09:45 pm
MLXXXp: Thanks for showing your mod!  I have the graphical version of that tester and it would be nice to upgrade it.

I mostly built my bangood kit (with case and rotary encoder) over the weekend. I prepared by doing a 4-wire measurement of the provided 0.1% 470K and 680 Ohm resistors. All were within spec, but I still paired them up so each was as close to the ideal ratio as possible. The value of this exercise is questionable, but I did it for fun.

I've paused to consider what I'm going to do about the test socket and leads. My current plan is to modify the case to shoehorn in three 2mm banana jacks rather than 2 4mm. Then I'm going to mount the DIP ZIF socket on a piece of protoboard and bolt/solder three 2mm banana plugs to the other side along one edge. It will be similar to the MK168/MK328. If I like the result, I'll probably have a small PCB made with some SMD test pads.

Parts are on order from China. At least some of them will be here within a week or so. I'll share details of my success (or failure!) once they arrive.

The other alternative I'm considering is to use some IC sockets as a riser to mount the ZIF socket onboard as giovannirat did and cut the case for it. Then, I'd make up an adapter that will allow 3 test leads.

Question: What, if any, downsides are there to replacing the 8MHz crystal with a 16MHz (and reflashing the MCU appropriately)? I figured the extra clock speed could help with UI responsiveness/refresh. Battery life might suffer, but I'd be ok with that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 14, 2015, 05:16:49 pm
Question: What, if any, downsides are there to replacing the 8MHz crystal with a 16MHz (and reflashing the MCU appropriately)? I figured the extra clock speed could help with UI responsiveness/refresh. Battery life might suffer, but I'd be ok with that.

A 16MHz crystal increases the accuracy and measurement range of some measurements, and also increases the top frequency of the squarewave generator. The only downside is that you have to build a new firmware with the MCU frequency set to 16MHz ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: 9a4wy on October 15, 2015, 12:37:59 pm
I have this one from ebay....
It has  1.07 FW
Could I flash it with new FW and what version please??
tnx...Kristian
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 15, 2015, 12:46:06 pm
I have this one from ebay....
It has  1.07 FW
Could I flash it with new FW and what version please??

Yes, 1.12k or 1.19m classic edition. Please see http://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/) and go to "trunk" for the current k-firmware or "Markus" for the m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 15, 2015, 01:31:06 pm
I have this one from ebay....
It has  1.07 FW
Could I flash it with new FW and what version please??

Specifically, in the case of using the k-version you can use directly the contents (files "TransistorTester.hex" and "TransistorTester.eep") of these folders:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328/?view=tar)
or
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/?view=tar)

Setting of fuses for ATmega328:
lfuse:0xf7 hfuse:0xd9 efuse:0x04 (0xfc)
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on October 18, 2015, 09:20:48 am
I need a reliable fish8840 scheme, you can help me
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on October 18, 2015, 09:44:25 am
I've paused to consider what I'm going to do about the test socket and leads. My current plan is to modify the case to shoehorn in three 2mm banana jacks rather than 2 4mm. Then I'm going to mount the DIP ZIF socket on a piece of protoboard and bolt/solder three 2mm banana plugs to the other side along one edge. It will be similar to the MK168/MK328. If I like the result, I'll probably have a small PCB made with some SMD test pads.


If you are successful please post pictures when you are done. Anything has to be better than the crappy socket supplied with the case. I installed my first tester into the case last week and had all kinds of problems with the supplied 5 hole socket. I was was trying to join the socket to the 2 mini banana terminals to the PCB (like the pictures on banggood for the case) and one of the socket's gold colored leads snapped right off. After some effort I was able to MacGuyver it back together and as soon as I got that one fixed one of the leads on the other side snapped off. I managed to get that one fixed and the whole thing assembled, but I went ahead and ordered one of the replacement sockets listed a couple of pages back because I really don't expect my fixes to hold for too long. While waiting for that to arrive I decided its not worth trying to even install. Due to a screw up on my initial order I got a second tester and case and had been planning to just not even use the case but I saw some pictures of a user that modified a different version of the tester/case to use the ZIF socket and think it would be worth trying. If I am ever successful in doing something similar I will probably disassemble the first one and just use it without the case. I was thinking it might be nice to have just the PCB mounted to my desk near all my parts for quick checking.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 18, 2015, 10:27:28 am
I need a reliable fish8840 scheme, you can help me
Fish8840 has many options of execution. You can see diagrams for several clones on my resource according to the link https://yadi.sk/d/yW8xa5NJgUo5z
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 18, 2015, 11:39:37 am
I need a reliable fish8840 scheme ...

This tester (by Fish8840) (http://lygte-info.dk/review/ComponentTester%20Fish8840%20UK.html) is consistent with standard electric connection. It is used with the G-LCD display (ST7565 controller). The difference is in the power supply circuit. See picture from the official manual (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar) - there you'll find a lot of useful information about this tester.

Connecting (SPI mode) the G-LCD display with the MCU is as follows:
PD0 - LCD-REST
PD1 - LCD-RS
PD2 - LCD-SCLK
PD3 - LCD-SID


Note:
The advantage of this tester is a simple way of adaptation for 16x2 character LCD.

Edit:
I edited and exported the wiring diagram (by indman) to its original state.
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on October 18, 2015, 06:38:02 pm
I need a reliable fish8840 scheme ...

This tester (by Fish8840) (http://lygte-info.dk/review/ComponentTester%20Fish8840%20UK.html) is consistent with standard electric connection. It is used with the G-LCD display (ST7565 controller). The difference is in the power supply circuit. See picture from the official manual (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar) - there you'll find a lot of useful information about this tester.

Connecting (SPI mode) the G-LCD display with the MCU is as follows:
PD0 - LCD-REST
PD1 - LCD-RS
PD2 - LCD-SCLK
PD3 - LCD-SID


Note:
The advantage of this tester is a simple way of adaptation for 16x2 character LCD.

Edit:
I edited and exported the wiring diagram (by indman) to its original state.


If I know him, but without modifying the original circuit   C20 + not to Q1
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 18, 2015, 06:53:10 pm
If I know him, but  C20 + not to Q1

Everything is OK.
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on October 18, 2015, 06:57:08 pm
I do not want to be indiscreet, but I only see Q1 to C18 and U5
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 18, 2015, 07:17:27 pm
On the PCB are two positions for C20 (the same is for C18) and it is therefore possible to use either a THT electrolytic capacitor or the tantalum capacitor.
In this case, on the position C20 and C18 is mounted tantalum capacitor.

Edit:
In the wiring diagram is reversed C20 and C18. In the Annex is a corrected circuit diagram :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 19, 2015, 06:40:52 am
tom666, thanks for corrections on the diagram C20 and C18! :D I upgrade the clone of Fish8840 with the big blue display - changed and added some elements in the diagram for correct operation of new firmwares from the author. Changes are selected in the red color on the diagram. The diagram in high quality can be downloaded at the link https://yadi.sk/d/yW8xa5NJgUo5z
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 19, 2015, 06:53:28 am
I've paused to consider what I'm going to do about the test socket and leads. My current plan is to modify the case to shoehorn in three 2mm banana jacks rather than 2 4mm. Then I'm going to mount the DIP ZIF socket on a piece of protoboard and bolt/solder three 2mm banana plugs to the other side along one edge. It will be similar to the MK168/MK328. If I like the result, I'll probably have a small PCB made with some SMD test pads.


If you are successful please post pictures when you are done. Anything has to be better than the crappy socket supplied with the case.
I plan to. If shipping on the 2mm sockets is as fast as it was on my last order from the same seller, I should have the parts by next weekend.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on October 19, 2015, 07:24:35 am
I've paused to consider what I'm going to do about the test socket and leads. My current plan is to modify the case to shoehorn in three 2mm banana jacks rather than 2 4mm. Then I'm going to mount the DIP ZIF socket on a piece of protoboard and bolt/solder three 2mm banana plugs to the other side along one edge. It will be similar to the MK168/MK328. If I like the result, I'll probably have a small PCB made with some SMD test pads.


If you are successful please post pictures when you are done. Anything has to be better than the crappy socket supplied with the case.
I plan to. If shipping on the 2mm sockets is as fast as it was on my last order from the same seller, I should have the parts by next weekend.

I've got some 2mm sockets laying around, really wish I would have thought to do the 3x2mm like you are saying. I will probably do that on the second case/tester I've got. Thanks for the great ideas.
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on October 19, 2015, 10:27:23 am
In this new scheme Fish8840. Already the reference TL431 is not used?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 19, 2015, 11:11:20 am
The voltage reference 2.5V is not used in the original version. It can be additionally fitted (parts U3 and R19) :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on October 19, 2015, 11:13:21 am
Thank  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 19, 2015, 11:13:51 am
In this new scheme Fish8840. Already the reference TL431 is not used?
No, it is the old diagram. After numerous experiments I came to a conclusion that application of TL431 doesn't lead to noticeable improving of parameters of a tester. It is more important to deliver the high-quality power supply voltage of the processor (Vcc=5.000V).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 19, 2015, 11:24:47 am
I changed a firmware for Fish8840BlueDisplay a little - added a homepage with the version and revision of audit. It decelerates start a little, but is more evident and it is convenient!
Attention! This firmware only for a board, in which divider of a supply of R15/R8 = 10k/3.3k!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 19, 2015, 12:43:31 pm
In this new scheme Fish8840. Already the reference TL431 is not used?
No, it is the old diagram. After numerous experiments I came to a conclusion that application of TL431 doesn't lead to noticeable improving of parameters of a tester. It is more important to deliver the high-quality power supply conditioner of the processor (Vcc=5.000V).

Yup, a MCP1702 is a much better investment than a TL431. A dedicated voltage reference makes sense when you're using something like a 78L05 or if the voltage reference is more than 10 times as accurate as the voltage regulator (MCP1702 is 0.4%).
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on October 19, 2015, 03:20:47 pm
Right now I'm trying to program Elnec ISP  smartprog2 and gives me VCC failure
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on October 19, 2015, 06:40:37 pm
This looks awesome! I'm a newbie to this thread, wondering if someone could point me to the most recent hardware to buy. I found this:

http://www.ebay.com/itm/M328-Transistor-Tester-Capacitor-ESR-Inductance-Resistor-LCR-Meter-NPN-PNP-MOS/281538451480 (http://www.ebay.com/itm/M328-Transistor-Tester-Capacitor-ESR-Inductance-Resistor-LCR-Meter-NPN-PNP-MOS/281538451480)

Is it the right one?

I tried to register at aliexpress but depending on the page, either it shows only google play and app store buttons, or when I actually can fill in a registration form, it does not like any of the fields; they all give validation errors.

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 19, 2015, 07:04:41 pm
I recommend this kit:
http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/381351024208 (http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/381351024208)
or
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

or set with the cabinet:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on October 19, 2015, 07:25:52 pm
I recommend this kit:
http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/381351024208 (http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/381351024208)
or
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

or set with the cabinet:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)

Seconded. Recently got this one and so far seems to be great. Its already go the encoder instead of push button switches, the 0.1% resistors where it matters and a voltage reference (instead of zener diode), although the general consensus seems to be it would be better to use a ldo voltage regulator like a MCP1702 instead of the 7805 that this kit comes with. If using the MCP1702-5002 you don't need the voltage reference. Of course if you have a MCP1702 you can go ahead and use that if you want, or order one online. They are only $0.52 on mouser.com.

Edit: Also it has the nice display and seems to support all the newer features that have been added to the firmware recently.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on October 19, 2015, 08:00:36 pm
I recommend this kit:
http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/381351024208 (http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/381351024208)
or
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

or set with the cabinet:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)

awesome, thanks!  Can you tell me where / if the source code is available? I tried searching on github & didn't find it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 20, 2015, 04:18:59 am
Got one of those with the case more out of curiosity than anything else since I keep hearing about it. It's actually smaller than it looks in the pictures, especially the display. The socket leads needed to be carefully bent and the two pairs at the ends of it connected together. Used heat-shrink tubing to insulate them just in case they decided to touch each other when I wasn't looking  :D. I simply used some spare resistor leads to connect it to the main board, but the angle at which they connect is not pretty. The two banana plugs became frequency counter inputs. When soldering in 10K resistors, I measured them and made sure that the combination at the frequency input provided roughly 2.4V, as it says in the manual. Another reason to measure is that I wanted to make the divider for battery voltage testing to be as close to 10K/3.3K as possible.

The firmware that this thing came with was horrible: It would crash randomly at the end of measurement and the tester would sit there sucking about 60mA from the battery until it was disconnected, but no such symptoms were seen after reflashing.

I wonder what I can do about the voltage reference though. It is not nearly as precise as I would like. Would measuring it and changing the expected voltage in software be equivalent to trimming or does it absolutely have to be precise?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 20, 2015, 04:21:11 am
awesome, thanks!  Can you tell me where / if the source code is available? I tried searching on github & didn't find it.

http://www.mikrocontroller.net/svnbrowser/transistortester/ (http://www.mikrocontroller.net/svnbrowser/transistortester/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 20, 2015, 06:54:03 am
awesome, thanks!  Can you tell me where / if the source code is available? I tried searching on github & didn't find it.

In this thread you'll find plenty of information (I put them there as "tom_pin" :)):
http://forum.banggood.com/forum-topic-92191.html (http://forum.banggood.com/forum-topic-92191.html)
and
http://forum.banggood.com/forum-topic-92191.html?page=2 (http://forum.banggood.com/forum-topic-92191.html?page=2)

Videos (not mine):
Soldering (https://www.youtube.com/watch?v=cvPgaKA1kW4)
Review (https://www.youtube.com/watch?v=EhRwuYe5qFE)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 20, 2015, 07:35:08 am
I wonder what I can do about the voltage reference though. It is not nearly as precise as I would like. Would measuring it and changing the expected voltage in software be equivalent to trimming or does it absolutely have to be precise?

The 2.5V reference is used only to check and calibrate the VCC voltage, but is not required. The merits of using the 2.5V ref. source (for example LM4040 AIZ2.5 [0.1%], TL431, LT1004 CZ-2.5 [0.8%], LM385-2.5, LM336Z-2.5 [0.8%]) only makes sense if it is 10 times more accurate than LDO 5V regulator, as otherwise this may lead to inferior results of the measurement. If is the 78L05 replaced with low-drop LDO MCP1702T (with typical deviation of 0.4%) is the 2.5V reference unnecessary! Another benefit of using low-drop voltage regulator (for example MCP1702-5002, LP2950CZ-5.0, LE50CZ) is to reduce power consumption and lower voltage drop with the ability to work with a little lower input voltage than standard 78L05 stabilizer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 20, 2015, 08:18:07 am
... a voltage reference (instead of zener diode) ...

The zener diode is used only in one type of tester (D1 on the attached picture), which is also sold in the variant without 8MHz crystal. Other types of testers (those that use the 2.5V reference source) use typically the TL431 in designs SMD or THT.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 20, 2015, 03:31:21 pm
I wonder what I can do about the voltage reference though. It is not nearly as precise as I would like. Would measuring it and changing the expected voltage in software be equivalent to trimming or does it absolutely have to be precise?

The 2.5V reference is used only to check and calibrate the VCC voltage, but is not required. The merits of using the 2.5V ref. source (for example LM4040 AIZ2.5 [0.1%], TL431, LT1004 CZ-2.5 [0.8%], LM385-2.5, LM336Z-2.5 [0.8%]) only makes sense if it is 10 times more accurate than LDO 5V regulator, as otherwise this may lead to inferior results of the measurement. If is the 78L05 replaced with low-drop LDO MCP1702T (with typical deviation of 0.4%) is the 2.5V reference unnecessary! Another benefit of using low-drop voltage regulator (for example MCP1702-5002, LP2950CZ-5.0, LE50CZ) is to reduce power consumption and lower voltage drop with the ability to work with a little lower input voltage than standard 78L05 stabilizer.

True, but doesn't answer my question, I'm afraid. Even an MCP1702T can be off by enough that calibration against a known reference would be beneficial, even if it's just a lowly TL431 that we're checking against. TL431 is adjustable, so it can be trimmed to be significantly more precise than any voltage regulator (easily by an order of magnitude). But I'm asking whether the same result can be achieved by a simple change in the software. Something tells me that it should be the case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 20, 2015, 03:47:07 pm
True, but doesn't answer my question, I'm afraid. Even an MCP1702T can be off by enough that calibration against a known reference would be beneficial, even if it's just a lowly TL431 that we're checking against. TL431 is adjustable, so it can be trimmed to be significantly more precise than any voltage regulator (easily by an order of magnitude). But I'm asking whether the same result can be achieved by a simple change in the software. Something tells me that it should be the case.

For the m-firmware you can set the voltage of the 2.5V reference via UREF_25 in config.h and for the k-firmware you have to change a value in Calibrate_UR.c, IIRC.
Title: Re: $20 LCR ESR Transistor checker project
Post by: torch on October 20, 2015, 04:14:45 pm
I've planned to add the fancy pinout in this release too but had/have to deal with a bereavement, a broken heart and a flu. Why do bad things happen all at once? So I ask you all if I should release v1.19m soon without the fancy pinout or if you are patient to wait another month or so?

I am sorry to hear of your misfortunes. Unfortunately, sometimes bad things happen to good people, please accept my condolences.

As for waiting: take all the time you want. I for one am having trouble following all the improvements and changes as they seem to come so fast. I could use the pause to catch up!!!  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 20, 2015, 04:45:05 pm
For the m-firmware you can set the voltage of the 2.5V reference via UREF_25 in config.h and for the k-firmware you have to change a value in Calibrate_UR.c, IIRC.

Thank you. What's funny is that I was actually looking at it and then got thrown off by the comment talking about "typical" and "datasheet". Could you elaborate on why you both have 2495mV as a default value there? I know that some (older?) vrefs are set to that instead of 2500mV, but we are all talking about precision references @2.5V here, and yet the software expects 2.495V by default?
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on October 20, 2015, 05:36:47 pm
awesome, thanks!  Can you tell me where / if the source code is available? I tried searching on github & didn't find it.

http://www.mikrocontroller.net/svnbrowser/transistortester/ (http://www.mikrocontroller.net/svnbrowser/transistortester/)

awesome! thanks for the software link. I ordered my hardware last night... expected delivery a few weeks from China.

in the meantime while reviewing the source code, is it supposed to be open source for community contributions or not? Every file has this text:

Quote
(c) 2012-2015 by Markus Reschke (madires@theca-tabellaria [dot] de)

that certainly does not sound very "open".

See:  http://opensource.org/licenses (http://opensource.org/licenses)

it would be a shame to have something so cool be protected by copyrights.

I would willing to contribute if indeed it is open source.....

Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 20, 2015, 05:56:32 pm
in the meantime while reviewing the source code, is it supposed to be open source for community contributions or not? Every file has this text:
Quote
(c) 2012-2015 by Markus Reschke (madires@theca-tabellaria [dot] de)
that certainly does not sound very "open".
See:  http://opensource.org/licenses (http://opensource.org/licenses)
it would be a shame to have something so cool be protected by copyrights.
I would willing to contribute if indeed it is open source.....

I think that if you use it only for personal use, it's all okay :)

For this kit I recommend using software by Karl-Heinz Kübbeler (I have successfully tested):
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?view=tar (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?view=tar)

You can directly use the contents from this folder:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 20, 2015, 05:57:05 pm
Thank you. What's funny is that I was actually looking at it and then got thrown off by the comment talking about "typical" and "datasheet". Could you elaborate on why you both have 2495mV as a default value there? I know that some (older?) vrefs are set to that instead of 2500mV, but we are all talking about precision references @2.5V here, and yet the software expects 2.495V by default?

That value is based on the typical voltage of some voltage reference we're using. You could check out the datasheet of the reference you got or measure the voltage with a accurate DMM (5.5 digits or better).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 20, 2015, 06:08:24 pm

Thank you. What's funny is that I was actually looking at it and then got thrown off by the comment talking about "typical" and "datasheet". Could you elaborate on why you both have 2495mV as a default value there? I know that some (older?) vrefs are set to that instead of 2500mV, but we are all talking about precision references @2.5V here, and yet the software expects 2.495V by default?
Excuse for volume presentation, I hope that the theory will be clear!
In the program by default  reference voltage for ADC 5v (external voltage on AVCC).
In case of detection on  input analog-to-digitial converter(ADC) less 1v the reference switches to internal reference supply source 1.1v.
Affect on internal reference 1.1v we can't (only if to select the processor with its minimum low value).
External reference 5v on AVCC (accuracy) depends on us!
  The source of sample voltage as reference supply source for ADC in this program doesn't work at PC4, and serves for correction of value of the reference voltage 5v the result of operation of ADC accepted in case of calculation. In firmwares of both authors correction is carried out on a formula:
  V5_calc=v5_avcc*v25Uref_pasport/V_izm_ADC PC4, where:
- V5_calc - calculated value of reference voltage 5v the result of operation of ADC  accepted in case of calculation.
- V5_avcc - value of voltage 5v on AVCC (the constant changed by the user)
- V25Uref_pasport - passport value of voltage of the REF (the constant changed by the user at Markus Reschke, at Karl-Heinz Kübbeler - in a code)
- V_izm_ADC PC4 - (real) voltage measured by ADC on PC4
  where the constants  V25Uref_pasport and V5_avcc are (in mV)?

At Markus Reschke in the config.h file:
#define UREF_VCC 5001
#define UREF_25 2495

At Karl-Heinz Kübbeler in the config.h files
#define U_VCC 5000
and  Calibrate_UR.c (value 2495)
ADCconfig.U_AVCC = (unsigned long) (ADCconfig.U_AVCC (unsigned long) * 2495) / mv2500;

Now, taking into account constants the formula assumes an air: V5_calc=5000*2495/V_izm_ADC PC4.
From a formula it is visible that 2495/V_izm_ADC PC4 coefficient of correction of an error of operation of ADC and in case of =2495 it is equal  1.0, according to V5_calc=5000*1=5000!
  If it is very simple, that, then when the REF on 2495mV and real voltage will be connected to PC4 on AVCC will be 5000mV!

PRACTICAL RECOMMENDATIONS!
- to select AVCC and REF for parameters the close to AVCC=5000mV and URef=2495mv or in case of assembly of a firmware to enter the real
values of voltage of AVCC and URef.
- in case of less exact AVCC to use more exact REF, otherwise it is no need also an ear REF, otherwise it is no need and will worsen result!
Good results with MCP1702-5002 with specification of V5_avcc without REF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 20, 2015, 06:18:32 pm
that certainly does not sound very "open".

See:  http://opensource.org/licenses (http://opensource.org/licenses)

it would be a shame to have something so cool be protected by copyrights.

I would willing to contribute if indeed it is open source.....

Haven't you read the README explaining the license issue? The whole project is OSHW but without a proper license so far. Also a copyright doesn't contradict an open source license. The problem will be fixed in about 2.5 months ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 20, 2015, 07:04:09 pm
@indman
Although I already had my answer by the time you posted, I appreciate your effort. For the benefit of other readers, I'd recommend changing "tension" to "voltage" everywhere in your post.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 20, 2015, 07:47:12 pm
in the meantime while reviewing the source code, is it supposed to be open source for community contributions or not? Every file has this text:

Quote
(c) 2012-2015 by Markus Reschke (madires@theca-tabellaria [dot] de)

that certainly does not sound very "open".

See:  http://opensource.org/licenses (http://opensource.org/licenses)

it would be a shame to have something so cool be protected by copyrights.

I would willing to contribute if indeed it is open source.....

Most open source licenses absolutely depend on copyright. Did you actually read any of the popular licenses mentioned on the page you linked to? For most/all of them, the rights granted under the license are granted by the copyright holder, whose identity is also stated in the license.

When I looked at the licensing for this project a while back, I found that it was kind of a morass. The original project, now dormant, project has a vague statement about being free for non-commercial use. The currently maintained forks have added significant new functionality, but it wasn't clear to me if they are technically derived from the original sources. In practice, Chinese sellers are making their own derivatives and selling them.

I'm not a lawyer, but it seems to me that the original author could try asserting his copyright at some point, but he only owns the copyright on the code he's written, or that has been transferred to him by the authors (and I don't think any has), so, in practice, about all he could do is make things difficult for the currently maintained forks. He could do so for any reason, but there don't seem to be many good reasons. He wouldn't be entitled to the code they authored, though he could try to strong-arm them into transferring copyright. It wouldn't be cheap and easy though, and there wouldn't be much payoff without spending even more to go after the Chinese sellers. That would be even more costly though, and the upside is, again, limited.

The people maintaining the current forks could pull their own hijinks, but they'd be opening up an even bigger can of worms, and again, with uncertain but limited payoff.

So, I think the best strategy for someone who likes the project and has the skills to contribute, is to do so, and retain copyright on your contributions. In doing so, you'll improve the project for yourself and others, and you'll add to the legal tangle that will make it difficult and expensive for anyone who wants to try and close or seize control of the project.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 20, 2015, 07:56:55 pm
that certainly does not sound very "open".

See:  http://opensource.org/licenses (http://opensource.org/licenses)

it would be a shame to have something so cool be protected by copyrights.

I would willing to contribute if indeed it is open source.....

Haven't you read the README explaining the license issue? The whole project is OHSW but without a proper license so far. Also a copyright doesn't contradict an open source license. The problem will be fixed in about 2.5 months ;)
Excellent!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 20, 2015, 08:06:50 pm
@indman
Although I already had my answer by the time you posted, I appreciate your effort. For the benefit of other readers, I'd recommend changing "tension" to "voltage" everywhere in your post.
Thanks, I corrected! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on October 20, 2015, 09:51:08 pm
that certainly does not sound very "open".

See:  http://opensource.org/licenses (http://opensource.org/licenses)

it would be a shame to have something so cool be protected by copyrights.

I would willing to contribute if indeed it is open source.....

Haven't you read the README explaining the license issue? The whole project is OHSW but without a proper license so far. Also a copyright doesn't contradict an open source license. The problem will be fixed in about 2.5 months ;)

Indeed, I read every word of the readme, as found in the root of the transistortester-trunk.tar.gz file, as shown below (nothing with regards to copyright):

Quote
This directory contains the program source for all TransistorTester versions.
To build the programming files for your ATmega microcontroller
please change to one of the following subdirectories:
mega8, default, mega328, mega168_strip_grid, mega328_strip_grid, mega328_dogm and mega328_strip_grid_dogm

The mega8 subdirectory contains the Makefile to build the programming data for a ATmega8 microcontroller.
The default subdirectory contains the Makefile to build the programming data for a ATmega168 controller.
The mega328 subdirectory contains the Makefile to build the programming data for a ATmega328 controller.
The subdirectories with the _strip_grid ending contains the Makefiles for the different connection
of the LCD used for the strip grid board and can not be used with the normal connection of the LCD.
You can find the programming data and the matching Makefile for the DOGM style LCD in the subdirectories
with dogm ending (mega328_dogm and mega328_strip_grid_dogm).

All subdirectories hold the Makefile the compiled data TransistorTester.hex and TransistorTester.eep!
The .hex data must be loaded to the flash memory and the .eep data must be loaded to the EEprom memory.
With the Linux operating system or with WinAVR the data can be loaded with the program avrdude to the
memory of the ATmega, controled with the Makefile. The connected ISP programmer must be supported by the program avrdude.
The data can also be loaded with any other program to the ATmega without control of the Makefile.

You can also create a own subdirectory and copy any of the Makefiles of the other directories to this
own subdirectory. Now you can set other options in this Makefile copy in your directory and try to build
your own TransistorTester programming data in this directory.

Please tell me, if you have problems with my software or if you have found errors.
You can send me a Email to kh_kuebbeler [at] web [dot] de or answer to my www.mikrocontroller.net (http://www.mikrocontroller.net) thread.

Good luck
Karl-Heinz Kübbeler


However, I think I did find the README you are referring to... in that was uploaded in a ZIP that was attached to message post here:
https://www.eevblog.com/forum/testgear/%2420-lcr-esr-transistor-checker-project/msg723065/#msg723065 (https://www.eevblog.com/forum/testgear/%2420-lcr-esr-transistor-checker-project/msg723065/#msg723065)

That says:
Quote
* License

The original author hasn't provided any information about the licence
under which the firmware is distributed. He only stated that it's open
source and any commercial user should contact him. Unfortunately we (
Karl-Heinz and I) haven't found any way to contact him. To remedy
this problem I will choose an open source license at 2016-01-01, if the
original author doesn't contact us to state his wishes until that date.
Since the source code of this firmware version is a major rewrite with
tons of new code and features, I think that this approach is justified.


* What's different?

Karl-Heinz has done a really great documentation of the tester. I recommend
to read it. Therefore I'll tell you just about the major differences to the
official release:

- user interface
  No worries! 
- adaptive component discharge function
- resistance measurement
  + dedicated method for resistances <10 Ohms (instead of using ESR check)
- capacitance measurement
  + starts at 5pF
  + additional method for caps from 4.7µF up to 47µF
  + correction/compensation method
- diodes
  + detection logic
- BJTs
  + V_f is interpolated for a more suitable (virtual) I_b based on hFE
- TRIACs
  + detection of MT1 and MT2
- structured source code
- some more I couldn't think of right now

There are more details in the sections below.
...(snip rest of readme)...

But as I found this in a zip file on this forum, not sure how that would apply to the source found here:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)

sorry I still don't see any license/copyrights in the tar.gz file.... all the readme's seem to be only compile instructions. Here's a list of all the readme's in there:

ComponentTester\trunk\ReadMe.txt
ComponentTester\trunk\mega328_T3_T4_st7565\ReadMe.txt
ComponentTester\trunk\ST7735\ReadMe.txt
ComponentTester\trunk\mega328_fish8840_OC\ReadMe.txt
ComponentTester\trunk\default\ReadMe.txt
ComponentTester\trunk\mega328_fish8840\ReadMe.txt
ComponentTester\trunk\mega168_strip_grid\ReadMe.txt
ComponentTester\trunk\mega328_wei_st7565\ReadMe.txt
ComponentTester\trunk\ILI9163\ReadMe.txt
ComponentTester\trunk\mega328_GM328\ReadMe.txt

Note a single instance of "license" or "copyright" mentioned. Certainly nothing saying "This program is free software; you can redistribute it".... but also nothing saying that it you can't... again, not even a copyright note.

I'm not trying to be difficult here, just trying to understand as a newbie to this topic before I get involved.  :)

All things considered... posting all that code on the public internet without even a "copyright" would seem to imply public domain.  ???


edit: changed email addresses to de-spider the [at] and [dot] for kh_kuebbeler
Title: Re: $20 LCR ESR Transistor checker project
Post by: ralphd on October 20, 2015, 10:55:39 pm
For the m-firmware you can set the voltage of the 2.5V reference via UREF_25 in config.h and for the k-firmware you have to change a value in Calibrate_UR.c, IIRC.

Thank you. What's funny is that I was actually looking at it and then got thrown off by the comment talking about "typical" and "datasheet". Could you elaborate on why you both have 2495mV as a default value there? I know that some (older?) vrefs are set to that instead of 2500mV, but we are all talking about precision references @2.5V here, and yet the software expects 2.495V by default?
The original TI 431 and many clones are 2.495V.
I like the cheap Wing Shing 0.3% parts.
http://nerdralph.blogspot.ca/2015/08/cheap-tl431-voltage-references.html (http://nerdralph.blogspot.ca/2015/08/cheap-tl431-voltage-references.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on October 21, 2015, 12:50:09 am
as I wait for my PC board to ship from China, I was poking around the dangerous prototypes forum for what appears to be the same Transistor Checker, and found this:

http://dangerousprototypes.com/forum/viewtopic.php?f=19&t=3260&start=375#p41127 (http://dangerousprototypes.com/forum/viewtopic.php?f=19&t=3260&start=375#p41127)

or more specifically, this link to the PDF manual (from 2012) that I thought might be of interest to share here:

http://www.mikrocontroller.net/attachment/143988/TTester_096k.pdf (http://www.mikrocontroller.net/attachment/143988/TTester_096k.pdf)

How similar is the current code base to that manual?

I'm looking forward to receiving my hardware! :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 21, 2015, 06:34:52 am
How similar is the current code base to that manual?

Software from version 0.96k to the current development version 1.12k achieve significant progress. Many new features were added.
I will mention, for example:
- f-Generator
- frequency measurement
- ability to control with rotary encoder
- 10-bit PWM generator
- measurement capacitors in the circuit
- separate measurement of capacitance and resistance
- DC voltage measurement
- etc.

Some features require add a hardware accessory.
Many important, useful and especially fresh information you will find here: ;)
http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar)
It is a file "tester.pdf" contained in the archive from the link.
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on October 21, 2015, 09:03:43 am
This new TransistorTester ESR PWM, uses Atmega328 or 328P?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on October 21, 2015, 09:44:06 am
Can you tell me where / if the source code is available? I tried searching on github & didn't find it.
https://github.com/svn2github/transistortester
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 21, 2015, 09:52:18 am
https://github.com/svn2github/transistortester

Is it a mirror of the official SVN repository (http://www.mikrocontroller.net/svnbrowser/transistortester/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 21, 2015, 10:21:58 am
This new TransistorTester ESR PWM, uses Atmega328 or 328P?

This kit comes with the ATmega328P. But in most other testers is also used the ATmega328P.
You can use any. Just M328P consumes lower power than M328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on October 21, 2015, 12:14:28 pm
Can you tell me where / if the source code is available? I tried searching on github & didn't find it.
https://github.com/svn2github/transistortester
That's very cool. Thank you.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on October 21, 2015, 12:19:45 pm
How similar is the current code base to that manual?

Software from version 0.96k to the current development version 1.12k achieve significant progress. Many new features were added.
I will mention, for example:
- f-Generator
- frequency measurement
- ability to control with rotary encoder
- 10-bit PWM generator
- measurement capacitors in the circuit
- separate measurement of capacitance and resistance
- DC voltage measurement
- etc.

Some features require add a hardware accessory.
Many important, useful and especially fresh information you will find here: ;)
http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar)
It is a file "tester.pdf" contained in the archive from the link.
wow, cool. Thanks for info.

I am really looking forward to my board delivery now! If only China had Amazon prime 2day delivery...  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 21, 2015, 01:14:02 pm
However, I think I did find the README you are referring to... in that was uploaded in a ZIP that was attached to message post here:
https://www.eevblog.com/forum/testgear/%2420-lcr-esr-transistor-checker-project/msg723065/#msg723065 (https://www.eevblog.com/forum/testgear/%2420-lcr-esr-transistor-checker-project/msg723065/#msg723065)

That says:
Quote
* License

The original author hasn't provided any information about the licence
under which the firmware is distributed. He only stated that it's open
source and any commercial user should contact him. Unfortunately we (
Karl-Heinz and I) haven't found any way to contact him. To remedy
this problem I will choose an open source license at 2016-01-01, if the
original author doesn't contact us to state his wishes until that date.
Since the source code of this firmware version is a major rewrite with
tons of new code and features, I think that this approach is justified.

But as I found this in a zip file on this forum, not sure how that would apply to the source found here:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)

Yep, that's the README of the m-firmware. It should be in each release package. AFAIK the k-firmware doesn't got any detailed information about copyright or a license. But it's not PD. It's OSHW without a standard license as explained in the m-firmware's README. The m-firmware is a different story because it is a complete rewrite. In January I'll choose a standard license for the m-firmware (presumably EUPL) for a proper legal framework. I can't speak for Karl-Heinz, but he seems to be not interested very much in such topics.

We both got no problems with Chinese clones as long as the manufacturers provide a link to the project's web page to the seller, especially for the documentation. And they should also provide their modified code and schematics. Most owners of the Transistor Tester got a Chinese clone and ask here or in the mikrocontroller.net forum for support. Karl-Heinz tries to track the major clones but there are simply too much meanwhile. The problem with the Chinese manufacturers is that they don't provide any support and a few people in the forums, like tom666 for example (don't be angry with me if I missed someone), do a great job to mitigate that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on October 21, 2015, 10:00:43 pm
Haven't you read the README explaining the license issue? The whole project is OHSW but without a proper license so far. Also a copyright doesn't contradict an open source license. The problem will be fixed in about 2.5 months ;)

:-\ (grumble,grumble its not OHSW, it's OSHW... It's a typo... let it go...  :=\

...information about copyright or a license. But it's not PD. It's OHSW without a standard license as explained in the m-firmware's README.

Ok.. that did it  |O You triggered my pedantic petulant perturbed inner grammar and spelling nazi.  :rant:

It is NOT fecking OHSW (Those feckin' Occupation Health Safety & Welfare do-gooders, shiny arsed jobsworths all of them. Elfin safety my arse!)
It is OSHW (Open Source Hardware)

 ;) :-/O
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on October 22, 2015, 12:01:39 am
Ok.. that did it  |O You triggered my pedantic petulant perturbed inner grammar and spelling nazi.  :rant:

It is NOT fecking OHSW
...
It is OSHW (Open Source Hardware)

Thank you! My pedantic petulant perturbed inner grammar and spelling nazi level was nearing preposterous levels.

Then again, perhaps madires' firmware actually is OHSW (Open Hearted SoftWare). :-DD

Edit: I had to correct my own typos. D'oh!
Title: Re: $20 LCR ESR Transistor checker project
Post by: 9a4wy on October 22, 2015, 11:10:27 am
I have this one from ebay....
It has  1.07 FW
Could I flash it with new FW and what version please??
tnx...Kristian
AVR ISP MKII can't conect to MCU...is it possible that SPI is locked in this chinese clone??
I have to find someone with AVR DRAGON or similar to try "parallel programming"...what do you think guys?
K
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 22, 2015, 12:29:05 pm
I have this one from ebay....
It has  1.07 FW
Could I flash it with new FW and what version please??
tnx...Kristian
AVR ISP MKII can't conect to MCU...is it possible that SPI is locked in this chinese clone??
I have to find someone with AVR DRAGON or similar to try "parallel programming"...what do you think guys?
K

Haven't seen any clones with SPI disabled so far, only with the memory lock bits set.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnatGoSplat on October 22, 2015, 07:09:20 pm
I would like to upgrade to the graphical version, but I also would like a case and 3 probes instead of ZIF.  There are a few with just 2 probes, but I really prefer 3.
So far, I've only found this one. http://www.ebay.com/itm/141709205814?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/141709205814?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
It's a bit more expensive, but I'm willing to spend a little more for case and probes.  However, no rotary encoder on that one.  I've never used a graphical version, what do I gain with the rotary encoder?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 23, 2015, 07:35:42 am
GnatGoSplat,MK-328 it is qualitative a collected clone with protection of measuring ports. But the encoder isn't set. It can be connected to this diagram according to the instruction from the author and to program a new firmware. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 23, 2015, 10:28:00 am
...  I've never used a graphical version, what do I gain with the rotary encoder?

The main advantage is a quicker way to control (especially motion) in the menu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 23, 2015, 12:31:45 pm
...  I've never used a graphical version, what do I gain with the rotary encoder?

The main advantage is a quicker way to control (especially motion) in the menu.

... and the optional squarewave generator in the m-firmware requires one for changing the frequency. Doing that with a single push button would be a nightmare.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnatGoSplat on October 23, 2015, 01:40:54 pm
Thanks, I do very much like the idea of a squarewave generator.  :-+
I'd better get one with rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nbritton on October 24, 2015, 02:24:47 am
Which one of these should I get? I have salvaged component bins filled with like 10,000 various unknown components, I need to sort through all of these. I can easily budget a few hundred dollars for something that can help get me organized. There are so many different variants of this project that I have no idea which one to get. How do you make sure you get one with the latest firmware, and which ones don't auto turn off after a few seconds, and can be powered by a AC adapter?
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on October 24, 2015, 03:39:24 am
Which one of these should I get? I have salvaged component bins filled with like 10,000 various unknown components, I need to sort through all of these. I can easily budget a few hundred dollars for something that can help get me organized. There are so many different variants of this project that I have no idea which one to get. How do you make sure you get one with the latest firmware, and which ones don't auto turn off after a few seconds, and can be powered by a AC adapter?

Pretty sure none of them come with the latest firmware. Especially with how quickly the the newer firmwares have been coming out. But thats one of the things that is so great about these, you can grab which firmware you want and build and install on your device. Which also means you can change things like auto turn off and many other features to however you want them (options can be set in the Makefile/fuses).

http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

This seems to be one of the newer ones and contains most of the recommended hardware, but since it comes as parts if you want to switch any parts out you can. I have 2 of these I have really been enjoying them. They also seem to be one of the more frequently discussed in this thread as of late. If you don't want to have to build your own firmware, the K version of the firmware already has prebuilt binaries that will work with the kit without any modifications.

Edit1: If you look in the mikrocontroller.net repo Software/trunk/mega328_st7565_kit/ directory, the TransistorTester.eep and TransistorTester.hex files are the prebuilt files ready to be installed on the mega328p that comes with the kit listed. These will work as is without any modification, of course if you want to change any options the Makefile is already there, all you have to do is rebuild it and install it on the tester.

Edit2: Pointed to correct firmware directory for kit in edit1
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 24, 2015, 03:40:14 am
The 2mm plugs and jacks I ordered arrived. I cut a piece of plastic to cover the original holes in the case and drill for the 2mm jacks. It looks like there will be plenty of room for three across.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=178027;image)

I'm gluing it on now. I'll probably wait until I have the protoboard I'm going to mount the ZIF socket on before I finalize the position of the jacks and drill new holes for them.

Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on October 24, 2015, 03:45:43 am
The 2mm plugs and jacks I ordered arrived. I cut a piece of plastic to cover the original holes in the case and drill for the 2mm jacks. It looks like there will be plenty of room for three across.

I'm gluing it on now. I'll probably wait until I have the protoboard I'm going to mount the ZIF socket on before I finalize the position of the jacks and drill new holes for them.

That looks nice, thanks for the pic.

Edit: Removed quoted picture
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on October 24, 2015, 09:21:44 am
Edit: If you look in the mikrocontroller.net repo Software/trunk/mega328_st7565/ directory, the TransistorTester.eep and TransistorTester.hex files are the prebuilt files ready to be installed on the arduino 328p that comes with the kit listed. These will work as is without any modification, of course if you want to change any options the Makefile is already there, all you have to do is rebuild it and install it on the tester.

Correct directory for this kit with G-LCD (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html) is mega328_st7565_kit (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar).
The reason for this difference is the specific setting for LG-LCD (see attached picture).

Notes:
* MCU ATmega328P is not "Arduino 328p". Arduino is the hardware platform based on a MCU ATmega (from Atmel Corporation).
* "CustomEngineerer" (but also other users), please do not use unnecessarily button "Quote".
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on October 24, 2015, 05:44:20 pm
Correct directory for this kit with G-LCD (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html) is mega328_st7565_kit (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar).
The reason for this difference is the specific setting for LG-LCD (see attached picture).

Notes:
* MCU ATmega328P is not "Arduino 328p". Arduino is the hardware platform based on a MCU ATmega (from Atmel Corporation).
* "CustomEngineerer" (but also other users), please do not use unnecessarily button "Quote".

You are correct. I should not try to answer stuff like this late at night. I have corrected my post above so as not to mislead people. And by unnecessarily use quote button, I assume you mean including the original picture (or any other media) in the reply? If so, I agree. Normally I try to remove those from my replies, just missed it. I have gone back and removed it now. Thanks for the corrections.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 24, 2015, 10:57:29 pm
There's also no need to quote the post immediately above yours unless you have reason to believe that it will be changed and thus make your reply seem less relevant.

@eas:
That looks like a very clean cut. May I ask what you used to cut that piece of plastic and how you're going to attach it (what kind of glue?)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 25, 2015, 08:16:27 am
The cut was a mess. I hacked it out of the case for a crappy wall-wart with some beefy side cutters (the first reasonably thick, non-clear plastic I could scrounge up). I cleaned up and squared off the edges with a couple files and contoured them.

I glued it with general purpose, non-corrosive (probably not important in this application) silicone adhesive because I figured I could rip it off if I decided I needed to start over. I crosshatched the backside and the surface of the case with an Xacto blade to try to provide better grip.

Before gluing it, I used the piece itself as a template for cutting a notch in the label.

Protoboard came today. I cut a piece and drilled it for the 2mm bannana plugs I got. I sacrificed one of them and clamped it in a drill chuck to use as a crude to cut threads in the holes. I'll post some photos once I have to finish it all up tomorrow.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 25, 2015, 05:38:38 pm
I see, thanks. I've been having a bit of difficulty cutting out rectangular plastic parts: Plastic always wants to have a curved edge, it seems...

Yeah, pictures are always good  :-+.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on October 26, 2015, 05:11:50 am
Looks good eas. A file fixes many a wonky cutting job.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 26, 2015, 05:11:59 am
I finished the case mod and assembly of my AVR transitor tester kit (http://techobsessed.net/2015/10/avr-transistor-kit-and-case-mod/). I'm pretty happy with the result. My protoboard skills need work, but I don't think I'm going to bother with making a PCB.

(http://d112tss1dzpest.cloudfront.net/wp-content/blogs.dir/22/files/2015/10/IMG_9139-e1445835793841-225x300.jpg?323d81) (http://techobsessed.net/2015/10/avr-transistor-kit-and-case-mod/)

Detail photos on my blog (http://techobsessed.net/2015/10/avr-transistor-kit-and-case-mod/)

Title: Re: $20 LCR ESR Transistor checker project
Post by: quantalume on October 26, 2015, 02:46:43 pm
eas, I like what you have done with your tester. Thanks for providing the eBay links to the plugs/jacks in your blog post. Do you note any parasitic reactances associated with the new wiring?
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on October 26, 2015, 05:48:42 pm
I haven't, but I didn't spend much time looking.

I did note that during the calibration using the ZIF socket, it detected a 0.02 Ohm difference between the highest and lowest resistance test points, which works out to ~10% of the ~0.20 Ohm average resistance detected. I haven't compare this to any of the ebay units I have (an EZM GM328, a Fish8840, and a 91Make "T4"). Nevermind, I misinterpreted and misremembered.

Any suggestions on how to better investigate?

I must say, this is my favorite of all the units. I like the rotary encoder, having a compact case, and the flexibility of test leads or socket. I think I may mod this further to allow in-system-programming without opening the case. The socketed AVR is less useful when I have to take out 3 sets of screws to swap it. Actually, the tedious part is mounting the board back in the case, since one has to slip standoffs under the board and keep them there until there is something to hold them in place. This fussyness could be remedied with some hot-glue, but I'd rather just have something I can access via the battery compartment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ebswift on November 02, 2015, 07:41:41 am
I bought one of the graphical units with the case and after checking it out, bought 7 more through work, they are very nice (I used the first one to check the resistor values to build the others).  Now, something that would be a cool mod is having fine grained control over the frequency generator along with amplitude to use as a lab teaching tool, has anyone been looking into that?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2015, 10:17:00 am
I bought one of the graphical units with the case and after checking it out, bought 7 more through work, they are very nice (I used the first one to check the resistor values to build the others).  Now, something that would be a cool mod is having fine grained control over the frequency generator along with amplitude to use as a lab teaching tool, has anyone been looking into that?

I'd shop for a DDS signal generator. The Transistor Tester generates a PWM and a swarewave based on the MCU's internal timers. So there are fequency steps based on the prescaler and counter value, i.e. non-continous frequency selection. The m-firmware allows you to select any supported frequency (sqarewave) using a rotary encoder. Add a potentiometer and you got an output level control ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 04, 2015, 08:24:50 pm
for inspiration ;)
Today I found this interesting video with a great idea - Audio Cassette Box as housing for the LCR-T3 Tester :-+

https://www.youtube.com/watch?v=Alj_dA-5L6w (https://www.youtube.com/watch?v=Alj_dA-5L6w)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 04, 2015, 08:25:47 pm
I've just released trendy 1.19m with fancy pinout for 3-pin semiconductors, driver for ILI9341/ILI9342, color display support and some bug fixes: http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on November 04, 2015, 09:18:07 pm
for inspiration ;)
Today I found this interesting video with a great idea - Audio Cassette Box as housing for the LCR-T3 Tester :-+
[/url]

Oh, wow. Hadn't thought of that. Thanks for posting, tom.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nbritton on November 05, 2015, 10:54:37 am
Which one of these should I get? I have salvaged component bins filled with like 10,000 various unknown components, I need to sort through all of these. I can easily budget a few hundred dollars for something that can help get me organized. There are so many different variants of this project that I have no idea which one to get. How do you make sure you get one with the latest firmware, and which ones don't auto turn off after a few seconds, and can be powered by a AC adapter?

Pretty sure none of them come with the latest firmware. Especially with how quickly the the newer firmwares have been coming out. But thats one of the things that is so great about these, you can grab which firmware you want and build and install on your device. Which also means you can change things like auto turn off and many other features to however you want them (options can be set in the Makefile/fuses).

http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

This seems to be one of the newer ones and contains most of the recommended hardware, but since it comes as parts if you want to switch any parts out you can. I have 2 of these I have really been enjoying them. They also seem to be one of the more frequently discussed in this thread as of late. If you don't want to have to build your own firmware, the K version of the firmware already has prebuilt binaries that will work with the kit without any modifications.

Edit1: If you look in the mikrocontroller.net repo Software/trunk/mega328_st7565_kit/ directory, the TransistorTester.eep and TransistorTester.hex files are the prebuilt files ready to be installed on the mega328p that comes with the kit listed. These will work as is without any modification, of course if you want to change any options the Makefile is already there, all you have to do is rebuild it and install it on the tester.

Edit2: Pointed to correct firmware directory for kit in edit1

Ok, thanks for your advice. I bought one and just finished assembling it. It says it is running version 1.12. How do I update it? The only AVR gear that I have are three Arduino Uno R3.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 05, 2015, 01:54:52 pm
... How do I update it? The only AVR gear that I have are three Arduino Uno R3.

Tutorial "How to use the Arduino as ISP Programmer (In-System Programmer)":
https://www.arduino.cc/en/Tutorial/ArduinoISP (https://www.arduino.cc/en/Tutorial/ArduinoISP)

The attached picture documenting my Arduino Duemilanove associated with the ATmega ISP Adapter (http://www.ebay.com/itm/ATmega8-ATmega48-ATMEGA88-Development-Board-AVR-NO-Chip-DIY-Kit-/281685097325).

I used official ArduinoISP sketch and this following commands:

For writing only Flash
avrdude -c avrisp -p m328p -P COM3 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a

For writing only Fuses (L=F7, H=D9, E=04)
avrdude -c avrisp -p m328p -P COM3 -b 19200 -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

For writing Flash + Fuses (L=F7, H=D9, E=04)
avrdude -c avrisp -p m328p -P COM3 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

Note:
For proper operation it is important to use a baud rate of 19200 and set the correct number of the communication port for Arduino.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on November 05, 2015, 11:20:10 pm
I've just released trendy 1.19m with fancy pinout for 3-pin semiconductors, driver for ILI9341/ILI9342, color display support and some bug fixes: http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)

Nice! What are the hardware requirements? What's the most future-proof PCB and controller for this version? I got lost in this!

I see you are using Subversion, what about switching to Git? Why do you put tarballs instead using the nice features of software versioning and revision control systems? That way, modifications would be easier to follow :D

If you get insterested about switcing to Git: Would you consider making a mirror at GitHub?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 06, 2015, 10:42:45 am
... What are the hardware requirements? ...

You can find the required information in the files "Readme", the "config.h" and the "Makefile".

Hardware is identical with the standard circuit diagram. To control is possible to use a rotary encoder connected to the ports PD2, PD3.
Supported MCU: ATmega328 or ATmega328P (1MHz, 8MHz or 16MHz)
Supported Displays: HD44780 (character display - 4 bit parallel), ST7565R (graphic display 128x64 - SPI), ILI9341/ILI9342 (graphic display 240x320 or 320x240 - SPI)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 06, 2015, 12:18:44 pm
I see you are using Subversion, what about switching to Git? Why do you put tarballs instead using the nice features of software versioning and revision control systems? That way, modifications would be easier to follow :D

If you get insterested about switcing to Git: Would you consider making a mirror at GitHub?

Karl-Heinz manages the SVN and I'd like to keep the m-firmware in the central repo. One stop shopping ;) I'm using git for another project already, but taking care about multiple mirrors wouldn't be one of my favourite tasks. Luckily someone else already does: https://github.com/svn2github/transistortester
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on November 06, 2015, 06:28:15 pm
... What are the hardware requirements? ...

You can find the required information in the files "Readme", the "config.h" and the "Makefile".

Hardware is identical with the standard circuit diagram. To control is possible to use a rotary encoder connected to the ports PD2, PD3.
Supported MCU: ATmega328 or ATmega328P (1MHz, 8MHz or 16MHz)
Supported Displays: HD44780 (character display - 4 bit parallel), ST7565R (graphic display 128x64 - SPI), ILI9341/ILI9342 (graphic display 240x320 or 320x240 - SPI)


Are these more powerful MCUs to be pin compatible then?

So using an ATmega328P + ILI9342 or ILI9341 is the way to go?

I see you are using Subversion, what about switching to Git? Why do you put tarballs instead using the nice features of software versioning and revision control systems? That way, modifications would be easier to follow :D

If you get insterested about switcing to Git: Would you consider making a mirror at GitHub?

Karl-Heinz manages the SVN and I'd like to keep the m-firmware in the central repo. One stop shopping ;) I'm using git for another project already, but taking care about multiple mirrors wouldn't be one of my favourite tasks. Luckily someone else already does: https://github.com/svn2github/transistortester

Oh, that's nice. It's a lot easier to look at the modifications. Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: ON1DQD on November 08, 2015, 01:07:00 am
for inspiration ;)
Today I found this interesting video with a great idea - Audio Cassette Box as housing for the LCR-T3 Tester :-+

https://www.youtube.com/watch?v=Alj_dA-5L6w (https://www.youtube.com/watch?v=Alj_dA-5L6w)

I have exactly the same device, can anyone point me to the latest firmware for it?

Thanks in advance!
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 08, 2015, 07:59:42 am
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867)

You can directly use the actual version (by Karl-Heinz Kübbeler) from the SVN archive designed for this type of tester:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/)
Fuses:
lfuse:0xf7 hfuse:0xd9 efuse:0xfc (0x04)

I recommend to read the manual:   
https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/)

Alternatively, a trendy software from Markus Reschke (madires):
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg723065/#msg723065 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg723065/#msg723065)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on November 09, 2015, 09:10:21 am
Is torch, the originator of this thread, still around?

It seems this well-developed (i.e., long :o) thread would benefit from the addition of a summary section in the very first post to collect all the requisite and related info (or links thereto) in one place and then updated as new versions of hardware/software come out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on November 09, 2015, 11:28:32 am
Is torch, the originator of this thread, still around?

It seems this well-developed (i.e., long :o) thread would benefit from the addition of a summary section in the very first post to collect all the requisite and related info (or links thereto) in one place and then updated as new versions of hardware/software come out.

Would be nice to have all the information in one place and something to show what software goes with what hardware.
I still have this non-working unit that I think only needs reprogramming.

(http://gokarters.com/smf/index.php?action=dlattach;topic=2454.0;attach=2024;image)

I am not very good when it comes to programming and need a noob tutorial. 

When power is applied and button is pressed you only get a bar across the screen.
I have tried to go through this thread to collect information but get pulled in other directions lol.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 09, 2015, 01:02:45 pm
When power is applied and button is pressed you only get a bar across the screen.

That's the case when the display isn't initialized. There are several posts in this thread about flashing the ATmega. An Arduino works as programmer too ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on November 09, 2015, 02:59:39 pm
When power is applied and button is pressed you only get a bar across the screen.

Does the microcontroller (or anything else) get warm while the screen is on?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on November 09, 2015, 03:22:01 pm


That's the case when the display isn't initialized. There are several posts in this thread about flashing the ATmega. An Arduino works as programmer too ;)

I will search back through the threads and see what I can find. If I can ever learn this I will post a YT video showing how.





Does the microcontroller (or anything else) get warm while the screen is on?

From the beginning.  I picked the unit up to test a transistor one day. I noticed it did nothing. Screen did not come on and I did not feel any heat in the controller.  The day before I had checked some HV caps. Was thinking that perhaps one was not discharged. I ordered a second unit.

Many months later I took the bad unit out and tried to read the controller. Then I tried writing the programs to it. But not knowing what I was doing may have corrupted the controller. Again I am a total noob at trying to do this. But after my failure I noticed that when I press the button I get a bar across the screen now. So it does show some sort of life. Perhaps it is toast. I am not sure.

I continued to play with it and this came up :
"BAT 4.8V empty"
I tried to program again and only get the “bar” now. I put it aside till I could learn more about it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on November 09, 2015, 05:41:01 pm
Assuming you are using a fresh battery, it sounds like either there is a problem with the voltage divider used to read the battery voltage, or the new firmware you installed isn't configured with the right divider ratio for calculating battery voltage (see BAT_NUMERATOR in the makefile).
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 10, 2015, 09:53:19 am
From the beginning.  I picked the unit up to test a transistor one day. I noticed it did nothing. Screen did not come on and I did not feel any heat in the controller.  The day before I had checked some HV caps. Was thinking that perhaps one was not discharged. I ordered a second unit.

According to the above information, I guess that is damaged MCU (it must be replaced). For flashing just use any ISP programmer (for example the USBasp).

On this type of tester is appropriate to make the following changes:
- the addition of the blocking capacitor between AVCC and GND (resolve the problem with error message "Cell")
- replacement the zener diode D1 with the source of the precision voltage 2.5V
This adjustment is described in the official manual. In the attached pdf file is the extracted relevant section of the manual.

Procedure for flashing a firmware into MCU (ATmega328P) with the USBasp programmer:

Required hardware:
- USBasp (price around US $1.87)

Required Software (download links below):
- USBasp Driver
- AVRDUDE
- Firmware

1. Unzip the downloaded files into a separate directory and then perform the installation USBasp driver.
2. Then connect (through the ISP cable) the USBasp programmer with the ISP connector on the tester.
3. Navigate to the folder with the unpacked software and perform this following command from command line:
avrdude -c usbasp -p m328p --B 4.0 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m
This command (also includes a section for writing fuses) can be copied and saved as e.g. "flash.bat" and stored in a prepared folder. In the future you can simplify this flashing of the firmware by the usage of "flash.bat".

Links:
USBasp - Driver:
http://www.fischl.de/usbasp/usbasp-windriver.2011-05-28.zip (http://www.fischl.de/usbasp/usbasp-windriver.2011-05-28.zip)
or
http://www.protostack.com/download/USBasp-win-driver-x86-x64-v3.0.7.zip (http://www.protostack.com/download/USBasp-win-driver-x86-x64-v3.0.7.zip)

AVRDUDE:
http://download.savannah.gnu.org/releases/avrdude/avrdude-6.1-mingw32.zip (http://download.savannah.gnu.org/releases/avrdude/avrdude-6.1-mingw32.zip)

Firmware:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/?view=tar)

USBasp - How to install driver on Windows 8:
http://letsmakerobots.com/node/36841 (http://letsmakerobots.com/node/36841)

USBasp - How to install driver on Windows 8.1:
http://openchrysalis.wordpress.com/2014/09/26/installing-usbasp-driver-software-in-windows-8-1/ (http://openchrysalis.wordpress.com/2014/09/26/installing-usbasp-driver-software-in-windows-8-1/)

USBasp - User Guide:
http://www.protostack.com/download/Users%20Guide%20(AC-PG-USBASP-UG-V2.0).pdf (http://www.protostack.com/download/Users%20Guide%20(AC-PG-USBASP-UG-V2.0).pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on November 10, 2015, 12:17:57 pm
From the beginning.  I picked the unit up to test a transistor one day. I noticed it did nothing. Screen did not come on and I did not feel any heat in the controller.  The day before I had checked some HV caps. Was thinking that perhaps one was not discharged. I ordered a second unit.

According to the above information, I guess that is damaged MCU (it must be replaced). For flashing just use any ISP programmer (for example the USBasp).


Now that was an excellent post!

I too think the MCU could be bad. Perhaps it is just corrupt.
I have that same programmer here on my desk already.

Below is a pic on what this one does when you press the button.
Also my programmer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on November 10, 2015, 05:27:45 pm
I Have a tester just like that with a similar problem. I had to replace the Microcontroller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on November 10, 2015, 05:46:06 pm
I Have a tester just like that with a similar problem. I had to replace the Microcontroller.

Think I will order a few of those controllers and give it a go also.

I just bought one of the new tester kit from banggood. Really like the way it works. I just uploaded a video on it.

I uploaded my video and put a thread here not to tie this one up:
https://www.eevblog.com/forum/other-blog-specific/diy-m12864-graphics-version-transistor-tester-kit-lcr-esr-pwm/new/#new (https://www.eevblog.com/forum/other-blog-specific/diy-m12864-graphics-version-transistor-tester-kit-lcr-esr-pwm/new/#new)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on November 10, 2015, 08:03:32 pm
Graham
Thanks for the reply on this. Great to know someone is close that knows a bit about these. I am headed out the door atm but reply back on this. Seems I can really use your help and perhaps you can teach this old dog a new trick. From previous test I think you are correct on it being a ATMega168. Would be nice to have it upgraded.
Really appreciate the information. Will get back with you.
Thanks   :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: 9a4wy on November 11, 2015, 12:55:57 pm

Could someone compile hex+eep files from 1.19m for me??
I have no tool for this now  :(
tnx
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 11, 2015, 01:35:19 pm

Could someone compile hex+eep files from 1.19m for me??
I have no tool for this now  :(

Please see http://www.avrtester.tode.cz/index.php?p=firmware (http://www.avrtester.tode.cz/index.php?p=firmware) (scroll down a little bit) for the classic edition.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 9a4wy on November 11, 2015, 08:00:20 pm
uhhh...
tnx very much....I feel dumb now :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on November 11, 2015, 08:16:13 pm
uhhh...
tnx very much....I feel dumb now :(

Dont feel dumb. This stuff can be difficult.
I cant even get the driver installed that tom666 posted  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on November 12, 2015, 02:08:55 am
Spent the last 2 hours on the laptop I am trying to set this up on for programming.
Giving up on it. will try on a windows 7 machine this week end. Instructions for drivers says you have to disable driver signature enforcement for win 8.1.  When I get to that page pc freezes up and cannot do anything.  Other than that pc runs fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlxDroidDev on November 12, 2015, 05:32:08 am
This is one great thread.

I am reading through everything (from page 1) and deciding if I order one ($23 on DX, but will end up costing $55 due to taxes) or build my own. I haven't read everything yet, but has anyone here had success with a homemade tester?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 12, 2015, 08:19:45 am
I haven't read everything yet, but has anyone here had success with a homemade tester?

Some time ago I made the following variants of this tester (see attached pictures). The simpler (SCT v1.7) does not contain auxiliary power circuit. Switching on and off is complemented through a separate switch.

Many references can be found on this discussion forum (these are links after text "Podklady k vyrobe (DIY):"):
http://svetelektro.com/Forum/avr-component-tester-rlc-esr-semiconductors-tester-t30285.html (http://svetelektro.com/Forum/avr-component-tester-rlc-esr-semiconductors-tester-t30285.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 12, 2015, 11:38:54 am
I am reading through everything (from page 1) and deciding if I order one ($23 on DX, but will end up costing $55 due to taxes) or build my own. I haven't read everything yet, but has anyone here had success with a homemade tester?

Yup, please see http://www.mikrocontroller.net/svnbrowser/transistortester/Hardware/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Hardware/Markus/) for some inspiration ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: lmester on November 12, 2015, 06:54:18 pm
I just finished one of these kits. I noticed a few problems with it.

First the n (Nano) character is corrupted. See pictures. I'm guessing that the character data in the ATmega is corrupted.

After performing a few tests I also noticed that the ATMega is pulling the 2.5v voltage reference to ground. (Pin 27) It will briefly rise to the normal 2.5v level when taking a measurement. Also, if you boot it up directly into the menu the reference will stay at 2.5v until you've completed a measurement. Has anyone else seen this behavior?

I usually work with Microchip PIC's and don't have a programmer for the ATmega. I've ordered a cheap USBasp programmer from Ebay. I'm going to see if a reflash fixes any of the problems.


Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on November 13, 2015, 09:12:45 am
@tom666

hello tom, can u pls compile me a flipped fw of fish8840? thank you very much
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 13, 2015, 09:20:41 am
I just finished one of these kits. I noticed a few problems with it.

First the n (Nano) character is corrupted. See pictures. I'm guessing that the character data in the ATmega is corrupted.

This cosmetic mistake I also registered.
The problem was solved by flashing a new firmware. On "banggood" I published instructions for updating firmware for this tester.
You can find it as 17 post at this link:
http://forum.banggood.com/forum-topic-92191.html?page=2 (http://forum.banggood.com/forum-topic-92191.html?page=2)

After performing a few tests I also noticed that the ATMega is pulling the 2.5v voltage reference to ground. (Pin 27) It will briefly rise to the normal 2.5v level when taking a measurement. Also, if you boot it up directly into the menu the reference will stay at 2.5v until you've completed a measurement. Has anyone else seen this behavior?

It's all right.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 13, 2015, 09:35:33 am
can u pls compile me a flipped fw of fish8840?
This is an original LCD or exchanged?
From which folder (SVN repositories) did you use the firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on November 13, 2015, 09:38:37 am
Hello tom, this is a new unit from the seller that sent me the broken lcd  :) ive used the fw that u gave me on page 84, its the Fish8840_v1.12k_r554.zip

thank you :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on November 13, 2015, 12:53:21 pm
Hello Tom, the text is still flipped  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 13, 2015, 01:28:33 pm
So try this
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on November 13, 2015, 01:41:59 pm
Thanks tom it works now, one question pls? why is that when i compile fw using the make file that u give i always get a bigger hex file?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 13, 2015, 01:55:55 pm
This is a problem of the older version of the compiler.

It was discussed several times here:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg747575/#msg747575 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg747575/#msg747575)
Title: Re: $20 LCR ESR Transistor checker project
Post by: papabol_24 on November 13, 2015, 01:57:35 pm
Oh ok thanks again tom,  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on November 14, 2015, 12:47:27 am
So decided to get back on this one tonight. Got some software loaded on a win 7 machine and read the mcu. Got a read. Was doing a few things and picked the tester up. The MCU was very hot. Guess this confirms that it is bad.   :palm:  Now to order some, and do a swap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlxDroidDev on November 14, 2015, 01:01:04 am
So decided to get back on this one tonight. Got some software loaded on a win 7 machine and read the mcu. Got a read. Was doing a few things and picked the tester up. The MCU was very hot. Guess this confirms that it is bad.   :palm:  Now to order some, and do a swap.

If you wee able to read something from it (for example, its fuses, using avrdude) after it cooled down, it's probably not damaged (yet). These Atmegas can take a lot of beating.

Check for any short-circuit that might be causing its pins to source more than 40mA. If that's what's happening, any other MCU you replace that with, will also be damaged.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on November 14, 2015, 01:50:27 am

If you wee able to read something from it (for example, its fuses, using avrdude) after it cooled down, it's probably not damaged (yet). These Atmegas can take a lot of beating.

Check for any short-circuit that might be causing its pins to source more than 40mA. If that's what's happening, any other MCU you replace that with, will also be damaged.

I had it under the scope earlier, no short circuit found. Not to say that there may not be  a component elsewhere that is shorted. Like I have said in a previous post I think a high voltage cap I tested may had been the culprit that caused the unit to fail.

Now as far as the read I got. Using Extreme burner.
This is my  second attempt ever with a programmer to read/write to a atmel chip. So I have know idea what I am seeing.
I did verify that it was actually doing something by clicking read with and without the header plugged in. Without being plugged in I got fails. With plugged in I got success.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on November 14, 2015, 11:00:26 am
These things are REALLY easy to blow up when testing a capacitor, particularly a HV one that you think is discharged but has recovered some charge - go on, ask me how I know  ::)

The symptoms when I did it were MCU getting hot and a tendency to identify everything as a mosfet! It still drove the display fine, presumably one or more MCU input protection diodes had fused.

When I replaced it, the first thing I did was to implement input protection - I used the relay option that shorts all the inputs together while not actively testing (as documented in the ttester.pdf for the 'k' version software). In my view this is a 'must have' modification.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2015, 11:06:09 am
This is my  second attempt ever with a programmer to read/write to a atmel chip. So I have know idea what I am seeing.
I did verify that it was actually doing something by clicking read with and without the header plugged in. Without being plugged in I got fails. With plugged in I got success.

If the read was successful you should be able to find a lot of known strings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2015, 11:10:12 am
When I replaced it, the first thing I did was to implement input protection - I used the relay option that shorts all the inputs together while not actively testing (as documented in the ttester.pdf for the 'k' version software). In my view this is a 'must have' modification.

Another solution is to add a SRV05?4. The m-firmware supports the protection relay also (HW_RELAY in config,h).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on November 14, 2015, 11:18:47 am
Quote
The m-firmware supports the protection relay also (HW_RELAY in config,h)

My apologies madires, I am only familiar with the other version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on November 14, 2015, 11:23:09 am
These things are REALLY easy to blow up when testing a capacitor, particularly a HV one that you think is discharged but has recovered some charge - go on, ask me how I know  ::)

The symptoms when I did it were MCU getting hot and a tendency to identify everything as a mosfet! It still drove the display fine, presumably one or more MCU input protection diodes had fused.

When I replaced it, the first thing I did was to implement input protection - I used the relay option that shorts all the inputs together while not actively testing (as documented in the ttester.pdf for the 'k' version software). In my view this is a 'must have' modification.

I would love to have the best design done in KiCad, with the latest hardware and all kind of recommendations+additions. It could be the "trendy" hardware branch ;)

I'll look about it if nobody does it earlier and I that happens quite common, I'm slow like a turtle. This will be my first "complex" project in my vocational school.

It ca  be an interesting way to convince my teacher to be the rebel guy that uses KiCad instead OrCAD 9.2. Yes, THAT old and only ONE fscking UNDO LEVEL! Even old KiCad from 2013 is less messy than this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on November 14, 2015, 12:00:59 pm
OrCAD 9.2? There's a blast from the past. It can do one thing I've not seen other software do - auto routing single sided boards with jumper links.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on November 14, 2015, 09:49:40 pm
OrCAD 9.2? There's a blast from the past. It can do one thing I've not seen other software do - auto routing single sided boards with jumper links.

OFFTOPIC WARNING
It's slightly less cumbersome to use than KiCad in the behavior of the wires, the rest is worse. It's full of windows too.

It has built-in simulation. I don't care about that so much, I hope to not get mad with SPICE model assignation when using KiCad.

Anyway, my computer isn't fast enough to run the EDA apps fluidly.
I need to be the classroom rebel and fight alone, there's no escape: No money for a faster computer, mine's an old workstation that was fast when bought but not anymore. Bloatware and lack of money sucks. I tried to "sin" by installing Windows, but there were severe issues that made impossible to finish the process.

Today I tried to run Circuit Wizard 1.5 on a local Internet cafe with Windows 10 and it worked worse than in Wine. I'm amazed!
END OF OFFTOPIC

I plan to try to replicate the best design under KiCad and publish it in GitHub, of course!
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on November 15, 2015, 11:34:00 pm
This is one great thread.

I am reading through everything (from page 1) and deciding if I order one ($23 on DX, but will end up costing $55 due to taxes) or build my own. I haven't read everything yet, but has anyone here had success with a homemade tester?

yes! complete success! :)

fwiw - I ordered mine here:

http://www.ebay.com/itm/381351024208 (http://www.ebay.com/itm/381351024208)

and it was only 4.99 shipping to USA (and apparently also to Brazil?)

(thanks again to whoever it was that recommend that link to me on this forum!)

In addition to all the nice detailed photos there, don't miss the "installation instructions" link:

https://www.dropbox.com/sh/uo7nr7xet09esbu/AAAMAjU0sE2hFqCXe0VAsGM_a?dl=0 (https://www.dropbox.com/sh/uo7nr7xet09esbu/AAAMAjU0sE2hFqCXe0VAsGM_a?dl=0)

but in case the link stops working, I've attached the file. There's definitely useful information there. (oops, the file is 3.5MB, and we can only upload 1MB here)

It was cool that the M328 also came pre-programmed. Assembly was really rather easy, and the device seems to work quite well. It is very cool.  :) Bravo!

I'm looking forward to digging into the source code.

http://www.mikrocontroller.net/svnbrowser/transistortester/ (http://www.mikrocontroller.net/svnbrowser/transistortester/)

https://github.com/svn2github/transistortester (https://github.com/svn2github/transistortester)

Enjoy!



Title: Re: $20 LCR ESR Transistor checker project
Post by: Datman on November 19, 2015, 03:55:44 pm
Hi all
I've received yesterday my GM328A V1.20 2015.05 EZM Electronics studio
http://www.ebay.com/itm/New-All-in-1-Component-Tester-Transistor-Diode-Capacitance-ESR-Meter-Inductance-/321511426333? (http://www.ebay.com/itm/New-All-in-1-Component-Tester-Transistor-Diode-Capacitance-ESR-Meter-Inductance-/321511426333?)

Do you think I have any chance of mounting a indented rotary encoder instead of the pushbutton?
Does anyone know where can I find the original source code and, if needed for the encoder, an appropriate code?

Thanks!
Gianluca
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on November 19, 2015, 05:25:18 pm
Bottom-line, yes you can, but you will need to adjust the firmware. You will find documentation, links to the different firmwares and a schematic of the base unit linked in this thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 19, 2015, 06:00:29 pm
I've received yesterday my GM328A V1.20 2015.05 EZM Electronics studio

Do you think I have any chance of mounting a indented rotary encoder instead of the pushbutton?
Does anyone know where can I find the original source code and, if needed for the encoder, an appropriate code?

Here you will find the answer (read also the following posts):
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg690137/#msg690137 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg690137/#msg690137)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Datman on November 20, 2015, 11:03:21 am
Uhmm... After a few posts, discussion has gone to batteries... :-(
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 20, 2015, 11:54:15 am
OK, so once again :) :
1. Is necessary to connect the encoder to MCU ports PD1 and PD3 as recommended.
2. Edit the file "Makefile" (CFLAGS += -DWITH_ROTARY_SWITCH=2 - enable encoder) and make compilation. This refers to the folder mega328_GM328.
3. Then this modified firmware flash to the MCU

That is all
Title: Re: $20 LCR ESR Transistor checker project
Post by: con-f-use on November 20, 2015, 04:10:42 pm
That is all

You forgot:

[4] Pray, you got the other Makefile options right for your specific tester (graphic display, resistor-devider-ratio, etc.).
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on November 20, 2015, 05:10:13 pm
Do you think I have any chance of mounting a indented rotary encoder instead of the pushbutton?
I have one with a 16 x 2 display but the way I added a rotary encoder may be of some use to you.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg777509/#msg777509 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg777509/#msg777509)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 20, 2015, 05:59:51 pm
You forgot:

[4] Pray, you got the other Makefile options right for your specific tester (graphic display, resistor-devider-ratio, etc.).

I did not forget ;)

Folder mega328_GM328 (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_GM328/) contains the firmware designed directly for his GM328 (http://www.ebay.com/itm/New-All-in-1-Component-Tester-Transistor-Diode-Capacitance-ESR-Meter-Inductance-/321511426333) tester. It need only set control with the rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on November 22, 2015, 08:23:07 pm
my transistor checker project kit arrived from China a couple of weeks ago. assembly went very smoothly and it works!  now my extra ATMEGA328P chips have arrived, so I was about to download the source code to start playing, when ta-da! I realized there's no JTAG, ISP, or any other pins available on the board for doing any sort of in-place, on-chip debugging.  :palm:

does anyone have a suggestion of how I might be able to compile & step through code with the '328 in place? I have both a bus pirate and AVR programmer on hand & hoping not to have to order an expensive emulator. can GDB / OpenOCD be used for this? I've not been able to find any information on how how this might be wired up.

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on November 22, 2015, 09:43:54 pm
https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/)

Download the complete tarball. Look for the PDF file it contains (ttester.pdf).
Find the solution in the circuit diagram on page 10.

Yours - Messtechniker
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on November 22, 2015, 10:17:13 pm
https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/)

Download the complete tarball. Look for the PDF file it contains (ttester.pdf).
Find the solution in the circuit diagram on page 10.

Yours - Messtechniker

aha! an ISP header in next version! most excellent. :) thanks for the tip. I was just poking though the '328 data sheet to see if those pins were directly exposed. now to solder one onto my board. I appreciate your response!  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on November 23, 2015, 12:41:44 am
update: ok, so the bus pirate apparently cannot program the '328 via OpenOCD/JTAG. I had forgotten that when I first played with my bus pirate and adapted this wiki:

https://github.com/gojimmypi/PiOCD/wiki/Using-a-Raspberry-Pi-with-a-Bus-Pirate-as-a-JTAG-Dongle-to-Linksys-BEFSR41-Router-V2 (https://github.com/gojimmypi/PiOCD/wiki/Using-a-Raspberry-Pi-with-a-Bus-Pirate-as-a-JTAG-Dongle-to-Linksys-BEFSR41-Router-V2)

specifically this note:

http://arduino.stackexchange.com/questions/3822/does-atmega-328-2560-chips-support-jtag-type-programmer-and-hardware-debugger (http://arduino.stackexchange.com/questions/3822/does-atmega-328-2560-chips-support-jtag-type-programmer-and-hardware-debugger)

I was however, able to get my AVR Pocket Programmer to actually program the TTester in place (see attached for my wiring diagram) from the Arduino IDE, however there's apparently no ability to actually step though code on the Raspberry Pi version if the IDE. Even if there was, I have no idea of where to start on getting the Arduino IDE to compile the transistor tester source. I'm able to successfully compile the Transistor checker using:

Code: [Select]
make -f Makefile

... but have yet to make the leap on getting that compiled code sent to the '328.... let alone actually single-step debugging.

Any further hints would be greatly appreciated :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on November 23, 2015, 06:29:39 am
Any further hints would be greatly appreciated :)

Coming up:

You may wish to look here:
https://www.mikrocontroller.net/topic/248078?page=8 (https://www.mikrocontroller.net/topic/248078?page=8)

Its a terribly long thread over 8 pages to date. But it contains a lot of valuable information
(some in English; brushing up your German could help though :)
And if in doubt, Karl-Heinz Kübbeler there is your (extremely helpful) man.
He does a lot of software development for the Transistor Tester
(which really is a multi-component tester).

Yours - Messtechniker
Title: Re: $20 LCR ESR Transistor checker project
Post by: Datman on November 23, 2015, 10:46:02 am
I haven't much time for it... :-(
I have my work and other projects in progress for fun...
My transistor tester has a graphic display and a SMD 328P, then I can't easily take apart the original uC for making experiments with one of the DIP uC I have! If i make something wrong I do it on the original uC! I could desolder the uC, of course, but I haven't another one and I can't put it on the Arduino board without an adapter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 23, 2015, 12:42:03 pm
update: ok, so the bus pirate apparently cannot program the '328 via OpenOCD/JTAG.

The bus pirate works great with avrdude. A little bit slow, but reliable. The ATmegas are programmed using ISP (http://www.atmel.com/images/doc0943.pdf (http://www.atmel.com/images/doc0943.pdf)).

BTW, I'm working on an IR RC test & decode feature right now (TSOP receiver module connected to the three test pins).
Title: Re: $20 LCR ESR Transistor checker project
Post by: johnka on November 26, 2015, 12:35:03 am
I'm thinking to build a transistor tester since I have most of the components but instead of a 16x2 lcd I'd prefer a graphic display 128x64.
Could I use one of these? link1 (http://www.ebay.com/itm/12864-Character-LCD-Display-Module-128x64-Dots-Graphic-Matrix-Green-Backlight-/281836554261?hash=item419ec48815:g:JG4AAOSwMpZUqh1C) link2 (http://www.ebay.com/itm/12864-Dots-Matrix-Graphic-LCD-Display-Screen-FOR-ESR-METER-Transistor-Tester-T4-/231696281399?hash=item35f22caf37:g:LYYAAOSwVL1WAETT) link3 (http://www.ebay.com/itm/12864-Character-LCD-Display-Module-128x64-Dots-Graphic-Matrix-Blue-Backlight-/281841925208?hash=item419f167c58:g:nyoAAOSw14xWMIRM)
I think the second is used on chinese boards with yellow pcb. Do the other two use the same interface to connect?
Also could I use a rotary encoder if I use one of these displays?
Title: Re: $20 LCR ESR Transistor checker project
Post by: lmester on November 26, 2015, 01:44:55 am
I recently got a cheap case for my tester. Nice case. The PCB fit without problems. I did notice that the contacts in the test socket were very tight. Impossible to plug in a small lead. It just bent. I had to loosen the contacts slightly. This test socket may be the weak point of this case. I have a box full of mystery components to test. Time to see if the socket holds up.

Also, if you plan on using this case don't install the zif socket. You'll need to remove it. I'd already installed it before I found this case. The zif leads are a little large for the PCB holes. It was a real pain to remove it. I had to use my SMD hot air gun to heat up the joints while pulling on the socket with pliers. A vacuum desoldering tool & solder wick wouldn't get it loose.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Shock on November 26, 2015, 02:09:47 am
Nice but you didn't link where the case is from and what transistor tester version you have (some extra photos of the inside will help).
Title: Re: $20 LCR ESR Transistor checker project
Post by: lmester on November 26, 2015, 07:08:40 am

The case was purchased from  banggood.com SKU273392. Also available from others. Ebay etc. See reply #1494 (page 100) for pics of the tester board and a bug that this version has. I'm still waiting for my AVR programmer to arrive from China... :=\

Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 26, 2015, 08:21:20 am
Nice but you didn't link where the case is from and what transistor tester version you have (some extra photos of the inside will help).

It is a well-known and popular DIY kit of the tester with graphic LCD display and control with a rotary encoder, which was here several times mentioned:
* DIY Kit (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)
* Case (http://www.banggood.com/Supporting-Shell-For-DIY-M12864-Graphics-Version-Transistor-Tester-Kit-p-989949.html)
* Set = DIY Kit + Case (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 26, 2015, 08:47:46 am
See reply #1494 (page 100) for pics of the tester board and a bug that this version has.

I registered this bug on one tester. This error is caused by a defective firmware. Flashing MCU with a functional firmware the problem is resolved.
Firmware upgrade process, I published here (http://forum.banggood.com/forum-topic-92191.html?page=2) (post #17).
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on November 26, 2015, 07:09:06 pm
There have been a few mods to allow use of the case and the ZIF socket.

One forum member cut the case to allow the ZIF socket and used an extra IC socket or two between the ZIF socket and the PCB as a riser to provide adequate clearance between the top of the case and the locking lever.

I used 2mm banana jacks to expose three of the test connections (http://techobsessed.net/2015/10/avr-transistor-kit-and-case-mod/), and then mounted the ZIF socket on a small piece of protoboard with 2mm banana plugs sticking out the back. I cut a small piece of scrap plastic to cover the original holes in the case.  This lets me easily switch between test leads and the ZIF socket. I've been using the test leads most of the time though, because I've been doing a lot of in-circuit checks of old capacitors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on November 27, 2015, 10:22:44 am
Gearbest - well known from MTBR as genuine YINDING dealer - sells this graphical DIY kit for $16.85 (http://www.gearbest.com/kits/pp_228313.html).

Newbies will find some useful instructions (http://www.instructables.com/id/AVR-Transistor-Tester/?ALLSTEPS) on instructables.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 27, 2015, 01:13:58 pm
An update about the IR remote control test and decode feature for the m-firmware. PDM, PWM and Bi-Phase demodulation works fine and I've also added a few common protocols:
- NEC (normal and extended)
- JVC
- Matsushita
- Sony SIRC (12, 15 and 20 bit)
- standard RC-5

There is a ton of protocols and I'd like to know if there any more common ones which I should add too. Please let me know!

PS: Never though that an universal IR RC could be so handy for testing IR protocols  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: johnka on November 27, 2015, 02:35:56 pm
Gearbest - well known from MTBR as genuine YINDING dealer - sells this graphical DIY kit for $16.85 (http://www.gearbest.com/kits/pp_228313.html).

Newbies will find some useful instructions (http://www.instructables.com/id/AVR-Transistor-Tester/?ALLSTEPS) on instructables.

Does this kit follow the original schematic?
Is there any way to power it from USB? What modifications should be done on the circuit?

Could anyone explain what are the conflicts between graphic displays and extra functions (rotary encoder, frequency counter e.t.c)?
The manual says: "In most cases the additional functions like rotary encoder or frequency counter are easier to build with the board versions for a character display, because the required data signals are routed to the display connector."
Does it refer to physical difficulty to solder extra wires on the same pins where the display is connected?
I want to build my own tester using the additional features and a graphic display. Would that be possible with this display?

ebay link (http://www.ebay.com/itm/128X64-128-64-Dots-Matrix-Graphic-LCD-Module-Display-Screen-Green-Backlight-LCM-/141825231502)
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on November 27, 2015, 06:15:22 pm
An update about the IR remote control test and decode feature for the m-firmware. PDM, PWM and Bi-Phase demodulation works fine and I've also added a few common protocols:
- NEC (normal and extended)
- JVC
- Matsushita
- Sony SIRC (12, 15 and 20 bit)
- standard RC-5

There is a ton of protocols and I'd like to know if there any more common ones which I should add too. Please let me know!

PS: Never though that an universal IR RC could be so handy for testing IR protocols  ;)
You have the major ones that I have seen used here in the US.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on November 28, 2015, 04:16:38 am
See reply #1494 (page 100) for pics of the tester board and a bug that this version has.

I registered this bug on one tester. This error is caused by a defective firmware. Flashing MCU with a functional firmware the problem is resolved.
Firmware upgrade process, I published here (http://forum.banggood.com/forum-topic-92191.html?page=2) (post #17).

Hi.

I have one of the China import Transistor Testers, and it seems to work quite well:

http://www.ebay.com/itm/381351024208 (http://www.ebay.com/itm/381351024208)

I'm trying to compile the source code onto a new ATMega128, but upon upload and startup, the red power LED is on, the LCD screen illuminates, but nothing is displayed. Perhaps I am using the wrong config.h settings? (see attached).

I've tried both this upload command:

Code: [Select]
make
avrdude -b 19200 -c avrispmkII -p m328p -v -U flash:w:ComponentTester.hex

as well as this one, from the banggood forum, above:

Code: [Select]
make
avrdude -c avrispmkII -p m328p -B 4.0 -e -U flash:w:"ComponentTester.hex":i -U eeprom:w:"ComponentTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

The chip is exactly the same ATMEGA328P-PU and I am able to burn a bootloader and upload a sample "blink" app from my Arduino.

But I simply cannot seem to make a successful burn of the Transistor tester. Any ideas?

clearly I'm a newbie at this.  :) any suggestions on getting the program to compile and upload correctly would be greatly appreciated.

Title: Re: $20 LCR ESR Transistor checker project
Post by: lmester on November 28, 2015, 07:12:04 am
Gearbest - well known from MTBR as genuine YINDING dealer - sells this graphical DIY kit for $16.85 (http://www.gearbest.com/kits/pp_228313.html).


I purchased this kit from Gearbest on October 30'th. It has a firmware problem. See reply #1494 (page 100). My tester reports firmware version 1.12k. The nano "n"  character is corrupted on the display. Other than this corrupted character, I've  found no  problems with it.

Unless Gearbest is now shipping  this kit with a corrected firmware version, you'll need to re-flash the chip.

I'm still waiting for my cheap Chinese USBASP AVR programmer. I should've spent another buck or two and purchased a programmer from a US seller.  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 28, 2015, 11:03:08 am
I'm trying to compile the source code onto a new ATMega128, but upon upload and startup, the red power LED is on, the LCD screen illuminates, but nothing is displayed. Perhaps I am using the wrong config.h settings? (see attached).

The lit LED indicates that the firmware is running, so you got a display issue. Based on your config.h the LCD should be a ST7565 type. Can you verify that? If it's a ST7565, please check the I/O pins used to connect the LCD. When it's another type you could try the k-firmware (a few more LCD types supported) or send me the LCD/tester and I'll write a driver.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 28, 2015, 11:20:41 am
I have one of the China import Transistor Testers, and it seems to work quite well:
http://www.ebay.com/itm/381351024208 (http://www.ebay.com/itm/381351024208)

I'm trying to compile the source code onto a new ATMega128, but upon upload and startup, the red power LED is on, the LCD screen illuminates, but nothing is displayed. Perhaps I am using the wrong config.h settings? (see attached).

I've tried both this upload command:
Code: [Select]
make
avrdude -b 19200 -c avrispmkII -p m328p -v -U flash:w:ComponentTester.hex

as well as this one, from the banggood forum, above:
Code: [Select]
make
avrdude -c avrispmkII -p m328p -B 4.0 -e -U flash:w:"ComponentTester.hex":i -U eeprom:w:"ComponentTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

The chip is exactly the same ATMEGA328P-PU and I am able to burn a bootloader and upload a sample "blink" app from my Arduino.
But I simply cannot seem to make a successful burn of the Transistor tester. Any ideas?

The problem is the used software (by Markus Reschke - "m" vesrion). For this type of tester I recommend you to use the version of the software from Karl-Heinz Kübbeler ("k" version). You can directly use the current development version from this link (folder already contains the compiled firmware):
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar)

For writing firmware to the MCU you can use only this command:
Code: [Select]
avrdude -c avrispmkII -p m328p -B 4.0 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 28, 2015, 11:38:47 am
The problem is the used software (by Markus Reschke - "m" vesrion). For this type of tester I recommend you to use the version of the software from Karl-Heinz Kübbeler ("k" version). You can directly use the current development version from this link (folder already contains the compiled firmware):
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar)

So it's a ST7565 but with standard I/O pins. The T3/T4 uses different pins. Please try

Code: [Select]
#define LCD_RESET        PD0            /* port pin used for /RES */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
//#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 28, 2015, 12:38:31 pm
Many questions :)

Does this kit follow the original schematic?

The scheme is identical to the original wiring. Missing just auxiliary circuit for measuring the frequency (voltage divider and an input capacitor). These elements are contained on the PCB.

Is there any way to power it from USB? What modifications should be done on the circuit?

It can be used DC-DC step-up converter. I recommend to ensure good filtration for the output voltage.

For example:
www.ebay.com/itm/2A-booster-board-DC-DC-step-up-module-input-2-24V-to-5-9-12-28V-Replace-XL6009-/131475227779 (http://www.ebay.com/itm/2A-booster-board-DC-DC-step-up-module-input-2-24V-to-5-9-12-28V-Replace-XL6009-/131475227779)

Could anyone explain what are the conflicts between graphic displays and extra functions (rotary encoder, frequency counter e.t.c)?

If they are for connecting display used MCU ports PD0, PD1, PD2, PD3 and PD5, everything is all right - this also applies for popular DIY KIT with graphic display and rotary encoder.
The problem has the LCR-T3 and LCR-T4 tester that uses ports PD1 to PD5. Port PD4 is reserved for measuring of the frequency and accordingly this function can not be used.
Other problem of these testers (LCR-T3 and LCR-T4 tester) are not adapted level of data signal MCU and G-LCD (5V vs 3.3V). Way of solving this problem you will find in the manual:
http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar)

The manual says: "In most cases the additional functions like rotary encoder or frequency counter are easier to build with the board versions for a character display, because the required data signals are routed to the display connector."
Does it refer to physical difficulty to solder extra wires on the same pins where the display is connected?

See attached picture from manual.

I want to build my own tester using the additional features and a graphic display. Would that be possible with this display?
ebay link (http://www.ebay.com/itm/128X64-128-64-Dots-Matrix-Graphic-LCD-Module-Display-Screen-Green-Backlight-LCM-/141825231502)

I don't Recommend. The reason is power supply by a 3V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 28, 2015, 12:56:23 pm
So it's a ST7565 but with standard I/O pins. The T3/T4 uses different pins. Please try

Code: [Select]
#define LCD_RESET        PD0            /* port pin used for /RES */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
//#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */

I know about this option, but because the user "gojimmypi" is not versed in the problem, so I recommended him version of the software, which is identical with the original version of the firmware (v1.12k).
Title: Re: $20 LCR ESR Transistor checker project
Post by: johnka on November 28, 2015, 01:44:20 pm
@tom666 Thanks for all your replies.
What display besides the 16x2 would you suggest so I could use the additional features?
The 3V display I posted above would be ok with a 3.3V regulator?
The roatry encoder is fine to be connected on the same pins used with the display? If the issue is only the frequency counter I could sacrifice that.
I want to build my own because I haven't find one that compines the additional features with input protection and a nice display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 28, 2015, 03:00:21 pm
What display besides the 16x2 would you suggest so I could use the additional features?

For example JLX12864G-378 (see attached pictures and datasheet).

The 3V display I posted above would be ok with a 3.3V regulator?

Only 3.3V power supply, however, will not solve the problem with diferent levels of data signals between MCU and G-LCD.

The roatry encoder is fine to be connected on the same pins used with the display?

Encoder can be connected to the ports PD1 and PD3 in parallel to the display.

I want to build my own because I haven't find one that compines the additional features with input protection and a nice display.

This tester contains a protection circuit:
http://www.ebay.com/itm/12864-GM328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-/331646342507 (http://www.ebay.com/itm/12864-GM328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-/331646342507)
Title: Re: $20 LCR ESR Transistor checker project
Post by: johnka on November 28, 2015, 04:14:51 pm
For example JLX12864G-378 (see attached pictures and datasheet).

Is this (http://www.banggood.com/12864-Screen-For-DIY-M12864-Graphics-Version-Transistor-Tester-Kit-p-1008517.html) the JLX12864G-378?
What protocol does it use to communicate? What column should I loook for on the manual's tables?

This tester contains a protection circuit:
http://www.ebay.com/itm/12864-GM328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-/331646342507 (http://www.ebay.com/itm/12864-GM328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-/331646342507)

I've seen this model and I've seen a post some pages back with a rotary encoder modification on this tester. The display looks like the 3V version we are talking about. How did they solve the voltage levels difference on data singals?
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on November 28, 2015, 04:21:08 pm
madires and tom666: thank you SO MUCH for your assistance!  :)  I think I'm getting closer, but not quite there.

I have one of the China import Transistor Testers, and it seems to work quite well:
http://www.ebay.com/itm/381351024208 (http://www.ebay.com/itm/381351024208)

I'm trying to compile the source code onto a new ATMega128, but upon upload and startup, the red power LED is on, the LCD screen illuminates, but nothing is displayed. Perhaps I am using the wrong config.h settings? (see attached).

I've tried both this upload command:
Code: [Select]
make
avrdude -b 19200 -c avrispmkII -p m328p -v -U flash:w:ComponentTester.hex

as well as this one, from the banggood forum, above:
Code: [Select]
make
avrdude -c avrispmkII -p m328p -B 4.0 -e -U flash:w:"ComponentTester.hex":i -U eeprom:w:"ComponentTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

The chip is exactly the same ATMEGA328P-PU and I am able to burn a bootloader and upload a sample "blink" app from my Arduino.
But I simply cannot seem to make a successful burn of the Transistor tester. Any ideas?

The problem is the used software (by Markus Reschke - "m" vesrion). For this type of tester I recommend you to use the version of the software from Karl-Heinz Kübbeler ("k" version). You can directly use the current development version from this link (folder already contains the compiled firmware):
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar)

For writing firmware to the MCU you can use only this command:
Code: [Select]
avrdude -c avrispmkII -p m328p -B 4.0 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

a sharp eye! yes, thanks for the correction: the target is ATMEGA328P-PU as noted in the commands, but incorrectly stated in my text as a  x128.

further, the already compiled code at your link code DOES upload and work perfectly! however I'm still not able to compile my own and upload that.


The problem is the used software (by Markus Reschke - "m" vesrion). For this type of tester I recommend you to use the version of the software from Karl-Heinz Kübbeler ("k" version). You can directly use the current development version from this link (folder already contains the compiled firmware):
The problem is the used software (by Markus Reschke - "m" vesrion). For this type of tester I recommend you to use the version of the software from Karl-Heinz Kübbeler ("k" version). You can directly use the current development version from this link (folder already contains the compiled firmware):
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar)

So it's a ST7565 but with standard I/O pins. The T3/T4 uses different pins. Please try

Code: [Select]
#define LCD_RESET        PD0            /* port pin used for /RES */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
//#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */


So this was sounding very promising... but still no-go. Same problem of LED-on, display illuminated, but nothing shown. Here's the section of config.h, with the entire file attached.

Code: [Select]
/*
 * Chinese clone T3/T4 with ST7585 display
 * - thanks to tom666 @ EEVblog forum
 */

//#if 0
#define LCD_ST7565R_SPI
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD4            /* port pin used for /RES */
#define LCD_A0           PD3            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD1            /* port pin used for SI (LCD's data input) */
// #define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
#define FONT_8X8_V                      /* 8x8 font, vertically aligned */
#define SYMBOLS_24X24_V                 /* 24x24 symbols, vertically aligned */
//#endif


So we know that the "mega328_st7565_kit" is what I have... but the question is: how is that version compiled?

again - thanks very much for your help! 
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 28, 2015, 04:28:43 pm
Code: [Select]
/*
 * Chinese clone T3/T4 with ST7585 display
 * - thanks to tom666 @ EEVblog forum
 */

//#if 0
#define LCD_ST7565R_SPI
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD4            /* port pin used for /RES */
#define LCD_A0           PD3            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD1            /* port pin used for SI (LCD's data input) */
// #define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
#define FONT_8X8_V                      /* 8x8 font, vertically aligned */
#define SYMBOLS_24X24_V                 /* 24x24 symbols, vertically aligned */
//#endif


I see, you haven't changed the I/O pins. Please change

Code: [Select]
#define LCD_RESET        PD4            /* port pin used for /RES */
#define LCD_A0           PD3            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD1            /* port pin used for SI (LCD's data input) */

to

Code: [Select]
#define LCD_RESET        PD0            /* port pin used for /RES */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on November 28, 2015, 04:58:29 pm
...
The problem is the used software (by Markus Reschke - "m" vesrion). For this type of tester I recommend you to use the version of the software from Karl-Heinz Kübbeler ("k" version). You can directly use the current development version from this link (folder already contains the compiled firmware):
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar)

For writing firmware to the MCU you can use only this command:
Code: [Select]
avrdude -c avrispmkII -p m328p -B 4.0 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

aha! I think I missed that point when I went off changing config.h - Do you know where I can find the source "k" version? this link:

http://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/)

seems to have only the "m" (Markus) source code, but the trunk data does have source code by kubi48  (I missed that earlier; lame, I know).  :palm:

so when I go to the mega328_st7565_kit directory and do a make, I get this error, perhaps just missing some files?

Code: [Select]
root@raspberrypi:~/transistortester/mega328_st7565_kit# make
avr-gcc  -Wall -DWITH_MENU -DNO_ICONS_DEMO -DSHORT_UNCAL_MSG -DSamplingADC_CNT -DWITH_ROTARY_SWITCH=2 -DFOUR_LINE_LCD -DLCD_ST7565_H_FLIP=0 -DLCD_ST7565_H_OFFSET=0 -DLCD_ST7565_V_FLIP=1 -DVOLUME_VALUE=37 -DFONT_8X15 -DICON_TYPE=3 -DBIG_TP -DINVERSE_TP -DWITH_SELFTEST -DAUTO_CAL -DWITH_AUTO_REF -DREF_C_KORR=12 -DREF_L_KORR=40 -DC_H_KORR=0 -DRMETER_WITH_L -DCAP_EMPTY_LEVEL=4 -DAUTOSCALE_ADC -DREF_R_KORR=3 -DESR_ZERO=20 -DNO_AREF_CAP -DPULLUP_DISABLE -DANZ_MESS=25 -DPOWER_OFF -DBAT_CHECK -DBAT_OUT=150 -DBAT_POOR=6400 -DBAT_NUMERATOR=133 -DBAT_DENOMINATOR=33 -mcall-prologues -DLCD_ST_TYPE=7565 -DLCD_ST7565_RESISTOR_RATIO=4 -DF_CPU=8000000UL -DMHZ_CPU=8 -mmcu=atmega328p -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT lcd_hw_4_bit.o -MF dep/lcd_hw_4_bit.o.d  -DSamplingADC -c  ../lcd_hw_4_bit.S
In file included from ../config.h:984:0,
                 from ../lcd_hw_4_bit.S:7:
../font.h:48:42: fatal error: fonts/8x15_vertikal_LSB_1.h: No such file or directory
compilation terminated.
Makefile:368: recipe for target 'lcd_hw_4_bit.o' failed
make: *** [lcd_hw_4_bit.o] Error 1


thanks again! the help is super appreciated!
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on November 28, 2015, 05:13:18 pm
Code: [Select]
/*
 * Chinese clone T3/T4 with ST7585 display
 * - thanks to tom666 @ EEVblog forum
 */

//#if 0
#define LCD_ST7565R_SPI
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD4            /* port pin used for /RES */
#define LCD_A0           PD3            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD1            /* port pin used for SI (LCD's data input) */
// #define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
#define FONT_8X8_V                      /* 8x8 font, vertically aligned */
#define SYMBOLS_24X24_V                 /* 24x24 symbols, vertically aligned */
//#endif


I see, you haven't changed the I/O pins. Please change

Code: [Select]
#define LCD_RESET        PD4            /* port pin used for /RES */
#define LCD_A0           PD3            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD1            /* port pin used for SI (LCD's data input) */

to

Code: [Select]
#define LCD_RESET        PD0            /* port pin used for /RES */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */

DOH!  :palm: sorry, another lame oversight on my part. time to take a break... BUT... I have success! (uh, well, in a sortta comical way).

so here's that section of my config.h

Code: [Select]
/*
 * Chinese clone T3/T4 with ST7585 display
 * - thanks to tom666 @ EEVblog forum
 */

//#if 0
#define LCD_ST7565R_SPI
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD0            /* port pin used for /RES */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
// #define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
#define FONT_8X8_V                      /* 8x8 font, vertically aligned */
#define SYMBOLS_24X24_V                 /* 24x24 symbols, vertically aligned */
//#endif

it works a bit differently than the software it shipped with (the mega328_st7565_kit code, that I've yet to successfully compile), but at least now I have this version working with a variety of messages displayed and no "main menu".... but the really crazy thing: is I need to look in a mirror to properly see what it says! lol. everything is reversed. perhaps just a bit more fine tuning of the config.h?

thanks again - I owe you a beer. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 28, 2015, 05:40:56 pm
so when I go to the mega328_st7565_kit directory and do a make, I get this error, perhaps just missing some files?

Code: [Select]
root@raspberrypi:~/transistortester/mega328_st7565_kit# make
avr-gcc  -Wall -DWITH_MENU -DNO_ICONS_DEMO -DSHORT_UNCAL_MSG -DSamplingADC_CNT -DWITH_ROTARY_SWITCH=2 -DFOUR_LINE_LCD -DLCD_ST7565_H_FLIP=0 -DLCD_ST7565_H_OFFSET=0 -DLCD_ST7565_V_FLIP=1 -DVOLUME_VALUE=37 -DFONT_8X15 -DICON_TYPE=3 -DBIG_TP -DINVERSE_TP -DWITH_SELFTEST -DAUTO_CAL -DWITH_AUTO_REF -DREF_C_KORR=12 -DREF_L_KORR=40 -DC_H_KORR=0 -DRMETER_WITH_L -DCAP_EMPTY_LEVEL=4 -DAUTOSCALE_ADC -DREF_R_KORR=3 -DESR_ZERO=20 -DNO_AREF_CAP -DPULLUP_DISABLE -DANZ_MESS=25 -DPOWER_OFF -DBAT_CHECK -DBAT_OUT=150 -DBAT_POOR=6400 -DBAT_NUMERATOR=133 -DBAT_DENOMINATOR=33 -mcall-prologues -DLCD_ST_TYPE=7565 -DLCD_ST7565_RESISTOR_RATIO=4 -DF_CPU=8000000UL -DMHZ_CPU=8 -mmcu=atmega328p -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT lcd_hw_4_bit.o -MF dep/lcd_hw_4_bit.o.d  -DSamplingADC -c  ../lcd_hw_4_bit.S
In file included from ../config.h:984:0,
                 from ../lcd_hw_4_bit.S:7:
../font.h:48:42: fatal error: fonts/8x15_vertikal_LSB_1.h: No such file or directory
compilation terminated.
Makefile:368: recipe for target 'lcd_hw_4_bit.o' failed
make: *** [lcd_hw_4_bit.o] Error 1

For the compilation you need to download the complete source code from this link:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?view=tar)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 28, 2015, 06:02:26 pm
Is this (http://www.banggood.com/12864-Screen-For-DIY-M12864-Graphics-Version-Transistor-Tester-Kit-p-1008517.html) the JLX12864G-378?

Just like that :)

What protocol does it use to communicate?

SPI:
http://web.engr.oregonstate.edu/~traylor/ece473/lectures/spi.pdf (http://web.engr.oregonstate.edu/~traylor/ece473/lectures/spi.pdf)

How did they solve the voltage levels difference on data singals?

You can use serial resistors or a chip like the 4050:
http://www.nxp.com/documents/data_sheet/HEF4050B.pdf (http://www.nxp.com/documents/data_sheet/HEF4050B.pdf)
http://www.ti.com/lit/ds/symlink/cd4049ub-mil.pdf (http://www.ti.com/lit/ds/symlink/cd4049ub-mil.pdf)

Other documents:
http://www.nxp.com/documents/application_note/AN240.pdf (http://www.nxp.com/documents/application_note/AN240.pdf)
http://www.daycounter.com/Circuits/Level-Translators/Level-Translators.phtml (http://www.daycounter.com/Circuits/Level-Translators/Level-Translators.phtml)
https://www.sparkfun.com/products/12009 (https://www.sparkfun.com/products/12009)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 28, 2015, 06:14:27 pm
it works a bit differently than the software it shipped with (the mega328_st7565_kit code, that I've yet to successfully compile), but at least now I have this version working with a variety of messages displayed and no "main menu".... but the really crazy thing: is I need to look in a mirror to properly see what it says! lol. everything is reversed. perhaps just a bit more fine tuning of the config.h?

Add the following line to your configuration:
Code: [Select]
#define LCD_FLIP_X
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on November 28, 2015, 07:18:53 pm
it works a bit differently than the software it shipped with (the mega328_st7565_kit code, that I've yet to successfully compile), but at least now I have this version working with a variety of messages displayed and no "main menu".... but the really crazy thing: is I need to look in a mirror to properly see what it says! lol. everything is reversed. perhaps just a bit more fine tuning of the config.h?

Add the following line to your configuration:
Code: [Select]
#define LCD_FLIP_X

success!  8) this worked perfectly, although I did need to also add:
Code: [Select]
#define LCD_OFFSET_X                    /* enable x offset of 4 dots */

such that my final config section for display looks like this:
Code: [Select]
/*
 * Chinese clone T3/T4 with ST7585 display
 * - thanks to tom666 @ EEVblog forum
 */

//#if 0
#define LCD_ST7565R_SPI
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD0            /* port pin used for /RES */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
// #define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_OFFSET_X                    /* enable x offset of 4 dots */
#define LCD_FLIP_X                      /* enable horizontal flip */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
#define FONT_8X8_V                      /* 8x8 font, vertically aligned */
#define SYMBOLS_24X24_V                 /* 24x24 symbols, vertically aligned */
//#endif


cool! so that's the "M" version, freshly compiled and working well, thanks a LOT for your help! Now on to the "K" version it shipped with... let's see if I can get that to work. :)

(hmm... on that topic, are there any plans to eventually merge the "K" and "M" versions?)

edit: added "m" version glory pic. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 28, 2015, 07:44:07 pm
@gojimmypi
instead #define LCD_OFFSET_X use #define LCD_OFFSET_Y

Edit:
instead #define LCD_FLIP_X use #define LCD_FLIP_Y
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 28, 2015, 08:03:35 pm
@gojimmypi
instead #define LCD_OFFSET_X use #define LCD_OFFSET_Y

Can't remember that there's such an option ;) BTW, for the rotary encoder PD1 and PD3 seem to be used, so gojimmypi could change

Code: [Select]
#define ENCODER_A        PD2       /* rotary encoder A signal */

to

Code: [Select]
#define ENCODER_A        PD1       /* rotary encoder A signal */

and check if that helps with the encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: johnka on November 28, 2015, 08:15:34 pm
I will get this (http://www.ebay.com/itm/12864-GM328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-/331646342507) tester but I also ordered one of these (http://www.ebay.com/itm/141825231502) displays to build my own adding all the additional features (rotary encoder, frequency counter e.t.c) with protection input.
COuld someone help me how to connect this display on the mcu? It has SDA(SI), SCL, A0, RST and CS pins. Is it ST7565 SPI?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 29, 2015, 10:20:29 am
@gojimmypi
instead #define LCD_OFFSET_X use #define LCD_OFFSET_Y

@gojimmypi
Sorry, I made a mistake in my post.
I thought this method for correction of text on G-LCD:
instead #define LCD_FLIP_X use #define LCD_FLIP_Y

Code: [Select]
//#if 0
#define LCD_ST7565R_SPI
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD0            /* port pin used for /RES */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
// #define LCD_CS        PD5      /* port pin used for /CS1 (optional) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_OFFSET_X                    /* enable x offset of 4 dots */
#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
#define FONT_8X8_V                      /* 8x8 font, vertically aligned */
#define SYMBOLS_24X24_V                 /* 24x24 symbols, vertically aligned */
//#endif
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2015, 11:52:28 am
I will get this (http://www.ebay.com/itm/12864-GM328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-/331646342507) tester but I also ordered one of these (http://www.ebay.com/itm/141825231502) displays to build my own adding all the additional features (rotary encoder, frequency counter e.t.c) with protection input.
COuld someone help me how to connect this display on the mcu? It has SDA(SI), SCL, A0, RST and CS pins. Is it ST7565 SPI?

Possibly some compatible controller, there's a hint in the parameters picture ;) I'd recommend to buy a few LCDs in case you want to try if the controller's SPI is 5V tolerant. Otherwise you need to add a level shifter, e.g. a 74HC4050.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gojimmypi on November 29, 2015, 11:18:19 pm
so when I go to the mega328_st7565_kit directory and do a make, I get this error, perhaps just missing some files?

Code: [Select]
root@raspberrypi:~/transistortester/mega328_st7565_kit# make
avr-gcc  -Wall -DWITH_MENU -DNO_ICONS_DEMO -DSHORT_UNCAL_MSG -DSamplingADC_CNT -DWITH_ROTARY_SWITCH=2 -DFOUR_LINE_LCD -DLCD_ST7565_H_FLIP=0 -DLCD_ST7565_H_OFFSET=0 -DLCD_ST7565_V_FLIP=1 -DVOLUME_VALUE=37 -DFONT_8X15 -DICON_TYPE=3 -DBIG_TP -DINVERSE_TP -DWITH_SELFTEST -DAUTO_CAL -DWITH_AUTO_REF -DREF_C_KORR=12 -DREF_L_KORR=40 -DC_H_KORR=0 -DRMETER_WITH_L -DCAP_EMPTY_LEVEL=4 -DAUTOSCALE_ADC -DREF_R_KORR=3 -DESR_ZERO=20 -DNO_AREF_CAP -DPULLUP_DISABLE -DANZ_MESS=25 -DPOWER_OFF -DBAT_CHECK -DBAT_OUT=150 -DBAT_POOR=6400 -DBAT_NUMERATOR=133 -DBAT_DENOMINATOR=33 -mcall-prologues -DLCD_ST_TYPE=7565 -DLCD_ST7565_RESISTOR_RATIO=4 -DF_CPU=8000000UL -DMHZ_CPU=8 -mmcu=atmega328p -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT lcd_hw_4_bit.o -MF dep/lcd_hw_4_bit.o.d  -DSamplingADC -c  ../lcd_hw_4_bit.S
In file included from ../config.h:984:0,
                 from ../lcd_hw_4_bit.S:7:
../font.h:48:42: fatal error: fonts/8x15_vertikal_LSB_1.h: No such file or directory
compilation terminated.
Makefile:368: recipe for target 'lcd_hw_4_bit.o' failed
make: *** [lcd_hw_4_bit.o] Error 1

For the compilation you need to download the complete source code from this link:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?view=tar)

Well, I don't know what happened there, as indeed there were many files missing. The tree was created, many files in sub-directories... but not all. weird. after I re-downloaded, and re-extracted, all the files are indeed present and I am able to compile! but I've spent hours trying to figure out why this "k" version does not work. As you may recall from prior threads,  I was able to get the "m" version working and uploaded with a few config.h tweaks (many thanks again to tom666 and madires) to get the display working properly.

However with this "k" version, things are much worse: the LED and display illuminate only when the rotary switch is pressed, then both go immediately dark. This is super weird, as the pre-compiled files upload and work perfectly - the same as the software that it shipped with. But I'm not able to reproduce this by doing my own compile.

If at all possible, would you mind kindly taking a peek at my make/avrdude log file (attached).  In short, I'm simply running "make" from the "mega328_st7565_kit" directory, then uploading with avrdude.

I've poured over the config and make files, and have found nothing obvious. I even did apt-get upgrade / apt-get update, and booted fresh. Still no-go.

Perhaps later this week I'll be better equipped to do some debugging, as I have an Atmel AVR Dragon in the mail! I'm open to suggestions if anyone has some ideas for reading material and/or online tutorials.

My last debugger was from quite some time ago, and was a genuine "emulator": hardware that actually replaced the CPU and connected to the PC via some rather expensive hardware. And the only thing I debugged was assembly language. How times have changed! I'm really looking forward to my Dragon. I hope it works well, as I almost spent the extra $$ to get the ICE.

Thanks again for all the help. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ryanna on November 30, 2015, 10:40:51 am
Hi,

Just bought this MK-168 Transistor Tester Iam using it normaly to test diodes and capacitors, and its working, but now i remember ever since it arrived its asking for calibration and i just short out the 3 clips and it work again, i used it about 3-5 times only then when i try to use it again when it test the battery voltage it shows 8 to 8.2 volts only and shows "Cell"  288mv 0mv 0mv, then it stay there and turns off, i suspect the battery is low so i changed it to new one but still the battery test shows only about 8.3-8.5V although my battery is new and reads 9.2on my voltmeter so its seems its now showing the correct battery status, but my problem is i cannot use it and it show only up to ""Cell"  288mv 0mv 0mv, page then it turn off i cannot use it, i tried checking the pcb for cold solder joints and check resistors and other component and all seems okay,

Please see attached photos when the leads are disconnected and when the lead are connected only 288mv 0mv 0mv, any body if you know or have idea how to solve this problem please advice.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on November 30, 2015, 11:25:16 am
@Ryana, I have a couple of those MK168's and they both have that issue with 9V batteries - I just assumed there is a reverse protection diode in circuit which would give a 0.6-0.7v drop.

I had an issue when I tried to use the calibration feature on one of them. I didn't have the correct capacitor to hand and ever since instead of giving the "Invalid/no component" message it reports back a capacitor when all the leads are disconnected. I flashed one of the newer firmwares and it's been ok since. Try flashing a fresh firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 30, 2015, 01:50:48 pm
@ryanna
I guess the MCU ports are damaged, which may be a result of testing the charged capacitors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ryanna on November 30, 2015, 03:06:16 pm
@Ryana, I have a couple of those MK168's and they both have that issue with 9V batteries - I just assumed there is a reverse protection diode in circuit which would give a 0.6-0.7v drop.

I had an issue when I tried to use the calibration feature on one of them. I didn't have the correct capacitor to hand and ever since instead of giving the "Invalid/no component" message it reports back a capacitor when all the leads are disconnected. I flashed one of the newer firmwares and it's been ok since. Try flashing a fresh firmware.


@Macbeth and tom666, thanks for the reply, do you have any link where you get the firmware that you use, also how can i flash it can i do it onboard or do i have to but a programming jig?I have no experience flashing firmware please guide me.

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on November 30, 2015, 05:03:59 pm
@ryanna

Procedure for flashing firmware:

Required hardware:
- USBasp programmer (http://www.ebay.com/itm/USBASP-USBISP-AVR-Programmer-Adapter-10-Pin-Cable-USB-ATMEGA8-ATMEGA128-Arduino-/310506909410) (price around US $1.87)
- AVR Development Board (http://www.ebay.com/itm/ATMEGA8-ATMEGA48-ATMEGA88-Development-Board-AVR-NO-Chip-DIY-Kit-/291550040876) (price around US $1.55) - or other AVR ISP adapter

Note:
Alternatively, it can use USBasp with a breadboard (for example 400 pin) - see attached picture.

Required Software (download links below):
- USBasp Driver
- AVRDUDE
- Firmware

1. Unzip the downloaded files into a separate directory and then perform installation of the USBasp driver.
2. Then remove MCU from the socket and insert it into the AVR ISP adapter.
3. Through the ISP cable connect the USBasp programmer with the ISP connector on the AVR ISP adapter.
4. Navigate to the folder with the unpacked software and perform this following command from command line:
   avrdude -c usbasp -p m328p -B 4.0 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m
   This command (also includes a section for writing fuses) can be copied and saved as e.g. "flash.bat" and stored in a prepared folder. In the future you can simplify this flashing of the firmware by the usage of "flash.bat".
5. After, if MCU is successfully burned, fit it back into the socket of the tester.
6. The first time the tester is suitable to calibrate. The procedure can be found in the manual.

Links:
USBasp - Driver:
http://www.fischl.de/usbasp/usbasp-windriver.2011-05-28.zip (http://www.fischl.de/usbasp/usbasp-windriver.2011-05-28.zip)
or
http://www.protostack.com/download/USBasp-win-driver-x86-x64-v3.0.7.zip (http://www.protostack.com/download/USBasp-win-driver-x86-x64-v3.0.7.zip)

AVRDUDE:
http://download.savannah.gnu.org/releases/avrdude/avrdude-6.1-mingw32.zip (http://download.savannah.gnu.org/releases/avrdude/avrdude-6.1-mingw32.zip)

Firmware:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/?view=tar)

USBasp - How to install driver on Windows 8:
http://letsmakerobots.com/node/36841 (http://letsmakerobots.com/node/36841)

USBasp - How to install driver on Windows 8.1:
http://openchrysalis.wordpress.com/2014/09/26/installing-usbasp-driver-software-in-windows-8-1/ (http://openchrysalis.wordpress.com/2014/09/26/installing-usbasp-driver-software-in-windows-8-1/)

USBasp - User Guide:
http://www.protostack.com/download/Users%20Guide%20(AC-PG-USBASP-UG-V2.0).pdf (http://www.protostack.com/download/Users%20Guide%20(AC-PG-USBASP-UG-V2.0).pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: onlooker on December 01, 2015, 03:21:28 am
I just made/modified a case to hold my tester. My crafting skill may need improvement, but, the case is cheap,  functional and easy to make. In fact, it is not just a case; it includes the needed power management circuitry (a over kill).

The original case was a USB power bank case for 4x18650 ($2.50 on ebay). One resistor was changed to have it output 8.5V and connecting to the tester. A flat cell Li battery from a old camera is used here as the power source. The two pictures below show some details.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=184863)

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=184865)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ryanna on December 01, 2015, 07:47:04 am
@tom666 thanks, ok i try buy those things first,one more question, if my case is what you said that i damaged the port can i buy a new ATMEGA and flash the software?

Thanks

Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on December 01, 2015, 09:34:34 am
@ryanna
In your case it will certainly be better to replace the MCU (http://www.ebay.com/itm/1pc-New-100-Original-ATMEGA328P-PU-Microcontrolle-r-With-ARDUINO-UNO-Bootloader-/281745599565).
Title: Re: $20 LCR ESR Transistor checker project
Post by: MorseMan on December 05, 2015, 03:51:01 pm
I noticed an odd 'event' on an MK-168 that I recently aquired.

While testing a capacitor the tester produced a screenfull of repeating characters.

The capacitor was 2u2, and had a fairly high esr, and I wondered if this 'bug' was peculiar to the MK-168 or maybe other testers/firmwares exhibit the same flaw.

In the process of trying out some comparison tests I came across other limitations (some may already be known about, but I thought I would add them for completeness of the report.

As a reference device I used an LCR-300 from Voltcraft. The $20 testers included an MTester with V2.07 firmware, an MK-168 with V1.07K firmware, and a Fish4480 with V2.2 firmware.

Using a 2u2 capacitor with a 1k Ohm preset in series I obtained the following results:

Preset @ zero Ohms >>> LCR-300 ESR 2.1R, MTester ESR 2.4R, MK-168 ESR 2.5R, Fish4480 ESR 2.5R

Preset @ 102.26 Ohms >>> LCR-300 ESR 104.3R, MTester ESR 16R, MK-168 ESR 93R, Fish4480 ESR 95R

Preset @ 151.17 Ohms >>> LCR-300 ESR 152.8R, MTester EST 17R, MK-168 ESR 130R, Fish4480 ESR 130R

Preset @ 198.35 Ohms >>> LCR-300 ESR 200R, MTester ESR 17R, MK-168 ESR 140R*, Fish4480 ESR 140R

Even when higher values were tried the MTester never read more than 17R max ESR. The MK-168 and the Fish4480 seemed to top-out at 140R. Only the Voltcraft instrument continued to give accurate readings even when the preset was set at its maximum, but then you would expect that due to it being a 'professional' instrument.

It was at settings above approx 160R that the MK-168 started to show a screenfull of rubbish.

Now, I accept that these units are cheap hobby-class devices, and for such basic hardware I think they do a tremendous job. I also accept that if a capacitor has a highish ESR these units would highlight that fact sufficiently to cause the person concerned to replace/reject the capacitor concerned.

My two 'puzzles' are:

1) Has the MTester been limited to show a maximum ESR of 17R for any technical reason,

2) How come the MK-168 goes crazy when presented with high ESRs?

Just curious!  :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 05, 2015, 04:49:16 pm
As a reference device I used an LCR-300 from Voltcraft. The $20 testers included an MTester with V2.07 firmware, an MK-168 with V1.07K firmware, and a Fish4480 with V2.2 firmware.

I don't know on which k-firmware versions the MTester and Fish4480 firmwares are based, but 1.07k is about 3 years old. The current ones are 1.12k and 1.19m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on December 05, 2015, 08:29:05 pm
@MorseMan,

You state you are testing a variable resistor in series with a capacitor. That is a circuit, not a component. Remember the old computer adage "Garbage in / Garbage out".

I can see you are trying to "emulate" an ESR, but that is simply not how it works in the real world. Those sorts of ESR are unheard of!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 06, 2015, 05:06:24 pm
Some news about the upcoming IR check feature in the m-firmware. I've managed to add support for multi frame/packet protocols too. So far, following protocols are supported:
  - JVC
  - Kaseikyo (aka Japanese Code, 48 bit)
  - Matsushita/Emerson
  - Motorola
  - NEC (standard & extended)
  - RC-5 (standard)
  - Samsung (32 bit Toshiba)
  - Sharp
  - Sony SIRC (12, 15 & 20 bit)

And for testing I've confiscated the RCs of three neighbours. ;D One was actually quite happy about that because he thought one of his RCs was broken.

Any more wishes for protocols?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 06, 2015, 11:13:26 pm
Sounds cool. I don't have any specific requests at the time, but...

Ever heard of the HiFi Remote website?

http://hifi-rem.ipower.com/jp1/lookup/ (http://hifi-rem.ipower.com/jp1/lookup/)

Take your pick, it lists quite a few protocols, including some rare ones.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 07, 2015, 01:45:20 pm
Sounds cool. I don't have any specific requests at the time, but...

Ever heard of the HiFi Remote website?

http://hifi-rem.ipower.com/jp1/lookup/ (http://hifi-rem.ipower.com/jp1/lookup/)

Take your pick, it lists quite a few protocols, including some rare ones.

Yup, I've stumbled about that one too ;) http://www.hifi-remote.com/wiki/index.php?title=DecodeIR (http://www.hifi-remote.com/wiki/index.php?title=DecodeIR) has a nice list. Also http://www.mikrocontroller.net/articles/IRMP (http://www.mikrocontroller.net/articles/IRMP) and http://www.sbprojects.com/knowledge/ir/index.php (http://www.sbprojects.com/knowledge/ir/index.php) . And there's http://lirc.sourceforge.net/remotes/ (http://lirc.sourceforge.net/remotes/) for individual RCs. I've also found a two part Elektor article (from 2001) about IR RC protocols.

Something which bothers me a little bit is that some protocols are actually identical besides a few µs difference in pulse/pause timing, but the start pulses (AGC burst) are far off. Could be caused by different carrier frequencies. The timing of most protocols is based on the carrier frequency, which makes sense. You just need to have one oscillator and derive all timings/clocks from that one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 07, 2015, 07:10:32 pm
Yes, all sorts of "fun" with those... ;D And then there's also the PT2262 chip. I was actually tempted to make an IR transmitter with it (since there is an IR version of it out there). You can find its datasheet at the bottom of this page:

http://www.enide.net/webcms/index.php?page=2262-2272-codec (http://www.enide.net/webcms/index.php?page=2262-2272-codec)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 07, 2015, 07:46:21 pm
You'll find v1.20m in the repos. Happy flashing!
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on December 08, 2015, 10:27:45 pm
The transistor checker is now an oscilloscope  :-DD  :-//

http://www.ebay.com/itm/Multi-Tester-for-Resistance-Capacitance-Frequency-DDS-Generator-Oscilloscope-/331726001725?hash=item4d3c69163d:g:kE4AAOxypthRw~on (http://www.ebay.com/itm/Multi-Tester-for-Resistance-Capacitance-Frequency-DDS-Generator-Oscilloscope-/331726001725?hash=item4d3c69163d:g:kE4AAOxypthRw~on)


 :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 09, 2015, 12:14:22 am
April jokes now?  :-//

You'll find v1.20m in the repos. Happy flashing!

Didn't I post with a "thank you" yet? Well, thank you! And that's no joke.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 09, 2015, 11:53:22 am
The transistor checker is now an oscilloscope  :-DD  :-//

http://www.ebay.com/itm/Multi-Tester-for-Resistance-Capacitance-Frequency-DDS-Generator-Oscilloscope-/331726001725?hash=item4d3c69163d:g:kE4AAOxypthRw~on (http://www.ebay.com/itm/Multi-Tester-for-Resistance-Capacitance-Frequency-DDS-Generator-Oscilloscope-/331726001725?hash=item4d3c69163d:g:kE4AAOxypthRw~on)

Nice find, but definitively no Transistor Tester. IIRC, someone already suggested a scope feature for the graphic LCD version of the tester :) 
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 09, 2015, 11:55:18 am
You'll find v1.20m in the repos. Happy flashing!

Didn't I post with a "thank you" yet? Well, thank you! And that's no joke.

You're welcome!
Title: Re: $20 LCR ESR Transistor checker project
Post by: wguibas on December 09, 2015, 02:49:35 pm
HI, been following this thread and just updated to windows 10.  If I try to make file I get errors.  I read back about 20 pages ago about msys-1.0 possibly causing this?  I found the file in winavr/utils/bin directory what am I supposed to replace it with or do?

(https://wayneg.smugmug.com/Electronics/i-39g7fx5/1/XL/dos-XL.jpg)

If I make the same directory on windows 7 I don't get the error.  I did get a hex file of 56K is that correct?

Thanks in advance for the help
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 09, 2015, 03:30:36 pm
If I make the same directory on windows 7 I don't get the error.  I did get a hex file of 56K is that correct?

The filesize seems to be right, but I can't help you with the Win10 problem. Sorry! Win10 free zone ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on December 09, 2015, 04:53:41 pm
 wguibas,
Are you trying to run it as administrator?
Title: Re: $20 LCR ESR Transistor checker project
Post by: wguibas on December 10, 2015, 12:15:42 am
I tried administrator now , same errors.  Before I upgraded to windows 10 I copied the drive.  If I put the windows 7 drive in it works fine, no errors.

run under administrator prompt
(https://wayneg.smugmug.com/Electronics/i-WpBfw5R/0/XL/admin%20test-XL.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on December 10, 2015, 09:18:06 am
@wguibas

Try this
The attached zip file contains a "MSYS-1.0.dll" that should be used to overwrite the original file that is located in the folder (for example) C:\WinAVR-20100110\utils\bin.
Title: Re: $20 LCR ESR Transistor checker project
Post by: wguibas on December 10, 2015, 03:51:41 pm
Thank You Tom666, worked like a charm!!

(https://wayneg.smugmug.com/Electronics/i-sjpmnSs/0/L/good%20make-L.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: majsta on December 13, 2015, 08:54:47 pm
Ok had hard time to program this thing:
Since I didn't have programmer I have decided to build myself one based on that schematics.
So like tom666 proposed on #939 I connected this device. For VCC I have used power from USB. But problem was PonyProg or At-prog were unable to detect properly Atmega328P. Then I tried AVRDude and that either didn't worked. I have selected ponyser but there was a problem device was not detected. So I looked at avrdude.conf and find out that in ponyser RESET was inverted for some reason????
Quote
reset = ~3;
so changing to:
Quote
reset = 3;
did the trick.
Now simply with AVRdudeGUI or in command line like:
Quote
avrdude -p ATMEGA328P -c ponyser -P COM1  -U flash:w:"C:\TransistorTester.hex":i

and then
Quote
avrdude -p ATMEGA328P -c ponyser -P COM1  -U eeprom:w:"C:\TransistorTester.eep":i

I hope that this could help someone. It is my first post here on this forum but I was reading a lot here lately, now was the time to write something :)



Update: Does this works for in-circuit testings of capacitors since I m getting some strange values with latest svn revision. Can someone please explain this to me. tnx



Title: Re: $20 LCR ESR Transistor checker project
Post by: avrank on December 14, 2015, 09:12:36 am
Please help me,
How to make measurements 10uh coil, can be displayed 30uH and not 0.03mH. Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on December 14, 2015, 03:59:42 pm
Please help me,
How to make measurements 10uh coil, can be displayed 30uH and not 0.03mH. Thanks.

Well, here goes:
1.) Do the full selftest with a 15 nF capacitor also at hand.
2.) Insert coil at 1 and 3.
3.) Insert 15 nF capacitor in parallel also at 1 and 3.
4.) Press the button.
5.) See what you get. See pic. enclosed

Yours - Messtechniker
Title: Re: $20 LCR ESR Transistor checker project
Post by: MatthewEveritt on December 14, 2015, 06:31:52 pm
Not sure if anyone's pointed this out yet (search didn't show anything obvious), but I just noticed that you can use ground leads from scope probes as make-shift test clips.
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=187297;image)
I don't like to say how long the ZIF socket will last doing this, so use at your own risk, the clips are pretty chunky.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 15, 2015, 10:01:04 pm
I am getting ready to buy one of these AVR component testers. Does anybody who follows the Mikrocontroller topic know if there are any group buys happening? Perhaps an updated design, with the hardware extensions built-in. Unfortunately, I can't read German.
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on December 16, 2015, 01:48:08 am
I am getting ready to buy one of these AVR component testers. Does anybody who follows the Mikrocontroller topic know if there are any group buys happening? Perhaps an updated design, with the hardware extensions built-in. Unfortunately, I can't read German.

 That would be useful. The only ones I come across are the completed Asian versions that lack full documentation of what they actually ship.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 16, 2015, 03:04:03 am
There is a Chinese fellow, Zhq, over in the Mikrocontroller forum (https://www.mikrocontroller.net/topic/248078?page=8#4383561) who has developed a very fancy tester. I hope he makes it available for sale. However, I suspect it would no longer fit in the "cheap" category.

(https://www.mikrocontroller.net/attachment/276745/QQ__20151209124243.jpg)

Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 16, 2015, 03:10:47 am
I searched online for a suitable device to buy, and this one seemed like the best option:
eBay item: 221952423890  seller: kiss_buyer  cost: 15.97 USD

Pros:Cons:
Did anybody else find any similar gems?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on December 16, 2015, 04:30:49 am
That's the one I got. It seemed to be the most feature-filled and the rotary encoder is much more friendly for accessing the menu. Although you have to assemble the kit, that also means you can verify the components or more easily make modifications (add test leads, use a different socket, make a custom enclosure, etc.).
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 16, 2015, 04:49:27 am
Thanks. How do you flash yours, bitseeker?
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on December 16, 2015, 05:50:04 am
Timesbeing,
Google Chrome will automatically translate any page for you. It is not 100% accurate but it will give you a very good idea of what is going on.
The nice thing about the Component tester mentioned above with the AVR processor in the DIP package is that you can use a programmer such as the TL866 to reprogram it. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: avrank on December 16, 2015, 06:38:40 am
Please help me,
How to make measurements 10uh coil, can be displayed 30uH and not 0.03mH. Thanks.

Well, here goes:
1.) Do the full selftest with a 15 nF capacitor also at hand.
2.) Insert coil at 1 and 3.
3.) Insert 15 nF capacitor in parallel also at 1 and 3.
4.) Press the button.
5.) See what you get. See pic. enclosed

Yours - Messtechniker

Thank you Mr. Messetechniker
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 16, 2015, 07:29:17 am
@casinada

Yes I tried translating. It's difficult to read. I would have to browse through all the topics. It's very easy to miss something, and there may be other German sites that I'm not even aware of. I want to be sure, so I asked here. Plus, everybody else can benefit from the answer too. That's what forums are for. :)

> you can use a programmer such as the TL866 to reprogram it.
I don't do THAT much programming. $50 seems like a lot to spend to flash a $15 gizmo. I think there some available on eBay for a few bucks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on December 16, 2015, 09:37:39 am
@timelessbeing

You can simply use to programming the MCU the following hardware:
- USBasp programmer (http://www.ebay.com/itm/USBASP-USBISP-AVR-Programmer-Adapter-10-Pin-Cable-USB-ATMEGA8-ATMEGA128-Arduino-/310506909410) (price around US $1.87)
- AVR Development Board (http://www.ebay.com/itm/ATMEGA8-ATMEGA48-ATMEGA88-Development-Board-AVR-NO-Chip-DIY-Kit-/291550040876) (price around US $1.55) - or other AVR ISP adapter

Alternatively, you can use USBasp with a breadboard.

For inspiration:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 16, 2015, 10:02:19 am
Dík, Tome.
I just won an eBay auction of the USBasp programmer for $1.25 US.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on December 16, 2015, 07:29:01 pm
Thanks. How do you flash yours, bitseeker?

I haven't reprogrammed mine yet. Instead of reflashing the original, I'm going to buy some new 328 for the newer firmware. That way I also have spares just in case I blow one up by forgetting to discharge a cap (yet another reason I chose this model, with the socketed microcontroller).

As far as programmers, there are many options, as others have posted, above. I have an Arduino Uno, which can also be used as an ISP.

e.g.,
http://www.instructables.com/id/Turn-Your-Arduino-Into-an-ISP/?ALLSTEPS (http://www.instructables.com/id/Turn-Your-Arduino-Into-an-ISP/?ALLSTEPS)

If you have to buy a programmer, try the USBasp.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on December 17, 2015, 12:15:59 am
I searched online for a suitable device to buy, and this one seemed like the best option:
eBay item: 221952423890  seller: kiss_buyer  cost: 15.97 USD

Pros:
  • socketed ATMega328
  • 128x64 backlit graphical display with support standoffs
  • Rotary encoder
  • Square wave gen, PWM, frequency counter
  • 8Mhz external crystal oscillator
  • Very reasonable price
  • Top-rated eBay seller
Cons:
  • assembly required
  • I don't see pads for programming the MCU in-place, which means I would need a socketed programmer like this one (http://www.ebay.com/itm/291550040876), right?

Did anybody else find any similar gems?

A number of us have built that one recently and been quite happy with it.

The main complaint has been that the optional case doesn't accommodate the ZIF socket provided with the PCB kit, and the socket provided with the case is sub par. I think the simplest solution I've seen posted is to stack one or two IC sockets to elevate the ZIF socket and then cut the case to accommodate it. I fitted the case with three 2mm banana sockets that I could use with test leads, or with a ZIF socket mounted on protoboard with banana plugs sticking out the bottom.

Also, some, including me, have seen corrupted characters, which is solved by flashing new firmware.

I think the lack of programming pins/pads is a bigger annoyance than it is with some of the other testers with a socketed MCU since the display is screwed down over it. I plan to bodge on some programming leads and expose a connection through the battery compartment so I can reprogram mine without having to disassemble the case and display
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 17, 2015, 01:40:35 am
I was thinking the same thing, just add some leads to put a programming socket into the battery compartment, but what stops me from doing it is the fact that it will add some stray capacitance. With wires moving around inside the case, it will be variable and somewhat difficult to cancel out.

Cons:
  • assembly required
  • ...

When did this become one of the cons for an electronics hobbyist?  :o
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 17, 2015, 10:29:11 am
I won't bother with a case. It doesn't feel right. I do like the idea of having 2 or 4 mm sockets though. That would make it more versatile, and easy to use with existing leads.

I hadn't thought about the screen blocking the MCU. Oh well, hopefully I won't be flashing too often. I'll just see how it goes.

When did this become one of the cons for an electronics hobbyist?  :o
Don't get me wrong. I love building up electronics. But in this case, I would rather spend my time either using the tester to identify parts to use for my projects, or making improvements on the tester. I like the idea of a compact pre-assembled board with a low profile surface mount parts. It's going to be a hassle obtaining through hole 0.1% resistors for the probe circuit. Maybe I'll just bodge in SMCs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 17, 2015, 11:05:46 am
One of participants of the forum mikrocontroller.net suggested to add in makefile a line "WITH_SamplingADC = 1" that increases permission in this range to 0,01pf. Measurement needs to be done on TP1-TP3 pins.

The additional measurement for low capacitance was submitted by PA3FWM.
Is this documented somewhere? Will it be enabled by default in future version?

There will be also one for low inductance (based on a resonant circuit with a parallel known C). The problem is that the firmware with both new features ... will exceed the flash size limit of the ATmega328... we're heading to the 644/1284 to allow new features and options.
Any updates on this? I assume that upgrading won't be achieved by simply swapping the MCUs, and would require redesigning the hardware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 17, 2015, 12:07:12 pm
The additional measurement for low capacitance was submitted by PA3FWM.
Is this documented somewhere? Will it be enabled by default in future version?

Please see Karl-Heinz' excellent documentation ( https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf ). The feature is an option and can be enabled in the Makefile of the k-firmware. Currently I have no plans for adding it to the m-firmware, because I think it's a feature for a precision bench multimeter and would require a 4 wire measurement for proper results.

Quote
There will be also one for low inductance (based on a resonant circuit with a parallel known C). The problem is that the firmware with both new features ... will exceed the flash size limit of the ATmega328... we're heading to the 644/1284 to allow new features and options.
Any updates on this? I assume that upgrading won't be achieved by simply swapping the MCUs, and would require redesigning the hardware?

The 644/1284 has a few pins more than the 328 ;) There's a circuit in the documentation, but I don't know if that is going to be the new standard one. I think we need some discussion of the use of the additional I/O pins. It would be good to have a fixed internal SPI bus with a few /CS lines for display, touchscreen and some new option, maybe also a I2C.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on December 17, 2015, 12:20:38 pm
It's going to be a hassle obtaining through hole 0.1% resistors for the probe circuit.

This DIY KIT with 128x64 G-LCD already contains 0.1% precision resistors (680 and 470k).
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on December 17, 2015, 11:35:08 pm
I won't bother with a case. It doesn't feel right. I do like the idea of having 2 or 4 mm sockets though. That would make it more versatile, and easy to use with existing leads.

I hadn't thought about the screen blocking the MCU. Oh well, hopefully I won't be flashing too often. I'll just see how it goes.

I had a previous model without a case (or rotary encoder). I got tired of being extra careful with it.

The screen is relatively easy to remove. I don't think it would be an excessive hassle for the occasional firmware update. It probably would be if you were doing development, or in the habit of installing nightly builds.

It's going to be a hassle obtaining through hole 0.1% resistors for the probe circuit.

This DIY KIT with 128x64 G-LCD already contains 0.1% precision resistors (680 and 470k).

Ah yes, I meant to mention that. It comes with precision resistors, and, at least in my case, they were all well within spec.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on December 18, 2015, 12:03:11 am
It's going to be a hassle obtaining through hole 0.1% resistors for the probe circuit.

This DIY KIT with 128x64 G-LCD already contains 0.1% precision resistors (680 and 470k).

Ah yes, I meant to mention that. It comes with precision resistors, and, at least in my case, they were all well within spec.

In the kit I got, all but one was within spec (680.80?). But, the ratios still work out fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on December 18, 2015, 12:14:59 am
I searched online for a suitable device to buy, and this one seemed like the best option:
eBay item: 221952423890  seller: kiss_buyer  cost: 15.97 USD

Anyway, if you do decide to get this model, it's a good price for it. The best deal I found was a short-lived sale on Banggood at $14.93 back in September.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 18, 2015, 09:16:05 am
Thanks for answering all my questions guys. :-+
The hardware is on its way. I'll report back with any interesting updates.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Intel on December 18, 2015, 03:47:13 pm
Hello,

I bought the LCR-T4 version from ebay and now I'm trying to modify it to run on 18650 battery but I need to adjust battery voltage settings. I uploaded the .hex file from "mega328_T3_T4_st7565" and it seems to be working. Then I tried adjusting BAT_POOR setting and compiling, but it does not fit in size even with default makefile:

Code: [Select]
8 MHz operation configured.
AVR Memory Usage
----------------
Device: atmega328p

Program:   37102 bytes (113.2% Full)
(.text + .data + .bootloader)

Data:        464 bytes (22.7% Full)
(.data + .bss + .noinit)

EEPROM:       46 bytes (4.5% Full)
(.eeprom)

I'm using latest WinAVR (from year 2010 lol). Tried atmel gnu toolchain but it gave me errors when compiling. Any ideas why it gets so large?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 18, 2015, 03:59:45 pm
I bought the LCR-T4 version from ebay and now I'm trying to modify it to run on 18650 battery but I need to adjust battery voltage settings. I uploaded the .hex file from "mega328_T3_T4_st7565" and it seems to be working. Then I tried adjusting BAT_POOR setting and compiling, but it does not fit in size even with default makefile:

I'm using latest WinAVR (from year 2010 lol). Tried atmel gnu toolchain but it gave me errors when compiling. Any ideas why it gets so large?

Please try a recent version of avr-gcc (better optimization)!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 18, 2015, 04:15:29 pm
Quick update on the m-firmware:
- Bug: The test button won't exit the IR detector when the IR receiver module is removed too early (endless loop).
  This is already fixed for the next version.
- IR detector: Trendy edition will support standard RC-6.
- Trendy edition will support two profiles for self-adjustment values (load & save), e.g. for two sets of probes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on December 18, 2015, 06:05:06 pm
Tried atmel gnu toolchain but it gave me errors when compiling. Any ideas why it gets so large?

If you do upgrade the AVR-GCC (I recommend to version 4.8.1) then try this fix of the compilation error (applies to Win 8, 8.1 & 10):
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg818096/#msg818096 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg818096/#msg818096)

Note:
Check the version of the compiler with command "avr-gcc --version".
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on December 18, 2015, 07:34:00 pm
Quick update on the m-firmware:
- Trendy edition will support two profiles for self-adjustment values (load & save), e.g. for two sets of probes.
Thanks for implementing this!  I'll have to give it a try soon.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on December 18, 2015, 07:42:48 pm
- Trendy edition will support two profiles for self-adjustment values (load & save), e.g. for two sets of probes.

That's excellent, madires. I haven't looked if there's room hardware- or software-wise, but it would be neat to have a toggle/slide switch connected to a pin on the 328 that would tell it which profile to use.  :-/O
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 18, 2015, 10:02:38 pm
Quick update on the m-firmware:
- Trendy edition will support two profiles for self-adjustment values (load & save), e.g. for two sets of probes.
Thanks for implementing this!  I'll have to give it a try soon.

I think, v1.21m is going to be a "happy new year" release  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 18, 2015, 11:11:37 pm
A number of us have built that one recently and been quite happy with it...

Is there pre-compiled firmware for my device (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg822554/#msg822554)?

Is it "mega328_st7565_kit" in the trunk directory?

It would be nice to use until I get familiar with compiling and all the make options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 19, 2015, 12:00:57 pm
Is there pre-compiled firmware for my device (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg822554/#msg822554)?

Is it "mega328_st7565_kit" in the trunk directory?

Yup!
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on December 19, 2015, 01:48:43 pm
Is there pre-compiled firmware for my device (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg822554/#msg822554)?
Is it "mega328_st7565_kit" in the trunk directory?
It would be nice to use until I get familiar with compiling and all the make options.

Detailed instructions by Tom66 you'll find at BG's forum:

DIY M12864 Graphics Version - FW and Updates (http://forum.banggood.com/forum-topic-92191.html?page=2)
Where can I get a programmed Atmel 328 ? (http://forum.banggood.com/forum-topic-99203.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Intel on December 19, 2015, 01:50:43 pm
I bought the LCR-T4 version from ebay and now I'm trying to modify it to run on 18650 battery but I need to adjust battery voltage settings. I uploaded the .hex file from "mega328_T3_T4_st7565" and it seems to be working. Then I tried adjusting BAT_POOR setting and compiling, but it does not fit in size even with default makefile:

I'm using latest WinAVR (from year 2010 lol). Tried atmel gnu toolchain but it gave me errors when compiling. Any ideas why it gets so large?

Please try a recent version of avr-gcc (better optimization)!
Tried atmel gnu toolchain but it gave me errors when compiling. Any ideas why it gets so large?

If you do upgrade the AVR-GCC (I recommend to version 4.8.1) then try this fix of the compilation error (applies to Win 8, 8.1 & 10):
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg818096/#msg818096 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg818096/#msg818096)

Note:
Check the version of the compiler with command "avr-gcc --version".

I managed to compile with avr-gcc 4.8.2 within size limits. However, finding binaries for that took a while and I couldn't find any newer ones. It seems that the only option getting avr-gcc for windows is to compile it from sources?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on December 19, 2015, 04:04:48 pm
Newest Toolchain from Atmel:

Atmel AVR 8-bit Toolchain 3.5.0 - Windows (http://www.atmel.com/System/BaseForm.aspx?target=tcm:26-64142)

Although I didn't test, still using 3.4.5.1522
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on December 19, 2015, 05:01:26 pm
It seems that the only option getting avr-gcc for windows is to compile it from sources?

For the purposes of updating the WinAVR you need download and unpack the contents of the Atmel AVR Toolchain 3.4.4 or 3.4.5 (contains compiler 4.8.1) to a directory with installed WinAVR.
In terms of efficiency compile I recommend using the compiler version 4.8.1, because the current version 4.9.2 (Toolchain 3.5.0) generates a larger files.

Atmel AVR Toolchain for Windows (direct download links):
* Toolchain 3.4.4 (http://www.atmel.com/images/avr8-gnu-toolchain-installer-3.4.4.24-win32.any.x86.exe) (contains compiler 4.8.1)
* Toolchain 3.4.5 (http://www.atmel.com/images/avr8-gnu-toolchain-installer-3.4.5.30-win32.any.x86.exe) (contains compiler 4.8.1)
* Toolchain 3.5.0 (http://www.atmel.com/images/avr8-gnu-toolchain-installer-3.5.0.85-win32.any.x86.exe) (contains compiler 4.9.2 - NOT recommended)

Notes:
- Self-extracting archives (downloaded exe files) can be extracted using WinRAR (http://www.rarlab.com/download.htm).
- Alternatively for the updating you can use the contents of the Arduino IDE (https://downloads.arduino.cc/arduino-1.6.7-windows.zip).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on December 19, 2015, 05:18:13 pm
In terms of efficiency compile I recommend using the compiler version 4.8.1, because the current version 4.9.2 (Toolchain 3.5.0) generates a larger files.
Is there not some command-line option to generate the smaller files like the earlier compiler?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on December 19, 2015, 05:26:51 pm
I don't compared with other optimization settings and options. Do you have any idea?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on December 19, 2015, 05:37:04 pm
Comparison of the compilers (standart settings):

avr-gcc 4.8.1:
TransistorTester.hex [77311b]
TransistorTester.eep [142b]

avr-gcc 4.9.2:
TransistorTester.hex [77671b]
TransistorTester.eep [142b]
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 19, 2015, 06:27:04 pm
Comparison of the compilers (standart settings):

avr-gcc 4.8.1:
TransistorTester.hex [77311b]

I'd compare the binary firmware. ;) The hex file is the ASCII encoded firmware including address information.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on December 19, 2015, 06:33:43 pm
Sure. But also the size of the file in binary form was bigger ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MickM on December 19, 2015, 09:57:54 pm
Hi;
  I have built several of these.
What I would like to know is the recommended pinout for ATMega644/1284 version.
As the firmware has outgrown the 328.

I could not find any hardware info on the larger versions.
I would like to stick with PTH parts for convenience, if possible.
It's nice to be able to pop the part out.

Is there a version for Arduino Mega 2560?

Thanks
   Mick M.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on December 20, 2015, 11:28:43 am
M328 can be still used even with all the new features.
All the other required information you will find in the official manual (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf).

Specifically these chapters:
2.7 Extented circuit with ATmega644 or ATmega1284 (page 28)
2.8 Buildup of a tester with ATmega1280 or Arduino Mega (page 30)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MickM on December 21, 2015, 05:40:31 pm
Thanks tom666;
   now I can use my old Sarduino for something.

Mick M.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on December 22, 2015, 01:21:50 am
M328 can be still used even with all the new features.
All the other required information you will find in the official manual (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf).

Specifically these chapters:
2.7 Extented circuit with ATmega644 or ATmega1284 (page 28)
2.8 Buildup of a tester with ATmega1280 or Arduino Mega (page 30)

Manual? Damn! That's better than most thesis I did read! It explains things better than all books on my vocational school.

Great work!

I did read about graphical LCD. Are there plans to to support color displays?

I'm sorry, these days my mind isn't in right shape. Maybe or was in the document.

What about discussing limitations /bugs in hardware and possible fixes?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 22, 2015, 11:40:20 am
I did read about graphical LCD. Are there plans to to support color displays?

The k-firmware supports ST7735, but just uses a fixed set of fg/bg colors IIRC. The m-firmware supports ILI9341/ILI9342 and uses a few colors.

BTW, LCD samples are welcome ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on December 22, 2015, 02:35:45 pm
I did read about graphical LCD. Are there plans to to support color displays?

The k-firmware supports ST7735, but just uses a fixed set of fg/bg colors IIRC. The m-firmware supports ILI9341/ILI9342 and uses a few colors.

BTW, LCD samples are welcome ;)
Can you provide a wishlist? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 22, 2015, 03:39:34 pm
BTW, LCD samples are welcome ;)
Can you provide a wishlist? :)

The m-firmware supports HD44780, ST7565 and ILI9341/ILI9342 at the moment. So any other LCD controller would be interesting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on December 22, 2015, 08:58:02 pm
I've installed ComponentTester-classic-1.20m firmware on my 2 X 16 tester. I decided to see if a Sharp GP1U587X IR module (http://www.mekatronix.com/downloads/docs/gp1u58x.pdf) would work with the new IR RC detector feature. When the tester is powered up with the module attached, and it probes to determine what kind of device is plugged in, it displays just the diode symbol followed by the number 6 (see attached photo).

I know the tester won't properly detect the module, since it's not a discrete component, but what does a diode symbol followed by 6 say that it thinks it is?  ???

P. S. In case anyone cares, this module doesn't work with the tester. It's specified to require 4.7V to 5.3V but the current that it draws through the 680 ohm resistor drops Vs on probe pin 2 to only 3.7V. It would be nice to have an IR mode option that provides Vs from one of the pins (PC0-2) directly attached to the probe pins for this case (with proper warnings about shorting the pin included in the documentation).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 22, 2015, 10:48:15 pm
I've installed ComponentTester-classic-1.20m firmware on my 2 X 16 tester. I decided to see if a Sharp GP1U587X IR module (http://www.mekatronix.com/downloads/docs/gp1u58x.pdf) would work with the new IR RC detector feature. When the tester is powered up with the module attached, and it probes to determine what kind of device is plugged in, it displays just the diode symbol followed by the number 6 (see attached photo).

It thinks that there are 6 diodes.

Quote
P. S. In case anyone cares, this module doesn't work with the tester. It's specified to require 4.7V to 5.3V but the current that it draws through the 680 ohm resistor drops Vs on probe pin 2 to only 3.7V. It would be nice to have an IR mode option that provides Vs from one of the pins (PC0-2) directly attached to the probe pins for this case (with proper warnings about shorting the pin included in the documentation).

In IR.c in function IR_Detector() please change

Code: [Select]
  ADC_PORT = 0;                         /* pull down directly: */
  ADC_DDR = (1 << TP1);                 /* probe-1 */
  /* pull up probe-2 via Rl, pull down probe-3 via Rh */
  R_DDR = (1 << (TP2 * 2)) | (2 << (TP3 * 2));    /* enable resistors */
  R_PORT = (1 << (TP2 * 2));              /* pull up probe-2, pull down probe-3 */

to

Code: [Select]
  ADC_PORT = (1 << TP2);
  ADC_DDR = (1 << TP1) | (1 << TP2);
  R_DDR = (2 << (TP3 * 2));
  R_PORT = 0;

to get Vcc just limited by the MCU's internal resistance (around 20 Ohms).
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on December 23, 2015, 12:27:10 am
It thinks that there are 6 diodes.

6 diodes across which probe pins?

Quote
In IR.c in function IR_Detector() please change [...]

Thanks for the code changes. I'll try them out as soon as I get some time (which might take a few days). If it works, would you consider making this configurable using a define in config.h or by some other easier means?
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: avrank on December 23, 2015, 08:33:27 am
Please help me,..
when I compile files with settings makefile "with sampilngADC", an error message appears on the image. But if no "with sampling ADC", no problem.     I compile with winavr2010. What is the problem ? And What should I do? Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 23, 2015, 11:38:30 am
6 diodes across which probe pins?

Across all three probe pins. The diode output function only supports up to 2 diodes. Any more diodes are displayed as you've already seen.

Quote
Thanks for the code changes. I'll try them out as soon as I get some time (which might take a few days). If it works, would you consider making this configurable using a define in config.h or by some other easier means?

No problem, I'd go for the #define switch.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on December 23, 2015, 02:48:06 pm
Thanks for the code changes. I'll try them out as soon as I get some time
madires,
I've tested your code changes to provide direct 5V to the IR sensor. The GP1U587X module now works, but not very well. Some remotes work fine. For others the remote has to be held very close to the sensor and at a certain angle or else I get garbage codes, and for a few I just always get random codes. I don't think the problems have anything to do with the tester. I'm guessing it's because my module has a band pass centre frequency of 56.8kHz, so it isn't very sensitive for remotes with lower carrier frequencies.

Because of this problem, I won't be using the GP1U587X module, so for me the change is no longer important. It's up to you if you want to add a #define and code for it.

I also have tried a VS1838B IR module (http://electronilab.co/wp-content/uploads/2015/05/vs1838b.pdf). It works fine, both without and with the code change.

Thanks for your help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 25, 2015, 03:32:21 pm
I've tested your code changes to provide direct 5V to the IR sensor. The GP1U587X module now works, but not very well. Some remotes work fine. For others the remote has to be held very close to the sensor and at a certain angle or else I get garbage codes, and for a few I just always get random codes. I don't think the problems have anything to do with the tester. I'm guessing it's because my module has a band pass centre frequency of 56.8kHz, so it isn't very sensitive for remotes with lower carrier frequencies.

Thanks for the feedback! I think you're right, most IR RCs use a 36 or 38kHz carrier. I've tested the decoder with about 20 or so RCs and an universal one using a 38kHz TSOP (2.5V-5.5V). One interesting thing I've found is that most no-name stuff uses the NEC protocol.

Quote
Because of this problem, I won't be using the GP1U587X module, so for me the change is no longer important. It's up to you if you want to add a #define and code for it.

I'll add a #define switch for it, in case someone has a 5V only IR receiver module. I should also add a remark about the supply voltage in the documentation.

Quote
I also have tried a VS1838B IR module (http://electronilab.co/wp-content/uploads/2015/05/vs1838b.pdf). It works fine, both without and with the code change.

Thanks for your help.

You're welcome!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 01, 2016, 06:09:57 pm
I've just released "Happy New Year" 1.21m ;)

Changes for Trendy:
- licensed under EUPL v1.1
- two adjustment profiles
- IR detector: RC-6, bugfix and support for 5V-only modules

Changes for Classic:
- licensed under EUPL v1.1
- IR detector: bugfix and support for 5V-only modules
- will most likely only receive bug fixes in the future (hint: upgrade to Trendy Edition!)

Presumably the next major step will be an ATmega 664/1284 board and support for 664/1284 in the m-firmware. And touchscreen of course.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on January 02, 2016, 07:28:23 am
Why changing to EUPL? Weekday about license compatibility?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 02, 2016, 12:47:05 pm
Why changing to EUPL? Weekday about license compatibility?

Actually it's not a change. There was no license before. And EUPL is pretty simple and straight forward.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on January 04, 2016, 08:39:14 am
Why changing to EUPL? Weekday about license compatibility?

Actually it's not a change. There was no license before. And EUPL is pretty simple and straight forward.

Severe license incompatibilities, especially the GPL variants.


https://joinup.ec.europa.eu/software/page/eupl/eupl-compatible-open-source-licences (https://joinup.ec.europa.eu/software/page/eupl/eupl-compatible-open-source-licences)
https://joinup.ec.europa.eu/community/eupl/news/eupl-or-gplv3-comparison-table-main-characteristics-and-differences (https://joinup.ec.europa.eu/community/eupl/news/eupl-or-gplv3-comparison-table-main-characteristics-and-differences)
http://www.gnu.org/licenses/license-list.en.html#EUPL (http://www.gnu.org/licenses/license-list.en.html#EUPL)

You can go "the french way" and relicense to CeCILL v2 (http://www.cecill.info/licences/Licence_CeCILL_V2-en.html), then you can relicense to GPLv2 and then you can relicense  it to GPLv3. To me as long time wannabe geek and bureaucracy hater, this seems like in the Brazil movie!

I think this license is quite problematic if someone wants to do a fork and add some functionality, like SCPI support (crazy idea, but I'm sure there are saner ones to do in more complex AVR chips).

Why did you choose that license? It seems done to make wet dreams to bureaucrats and politicians, but not so practical in the FLOSS community.

I don't want to offend you. I'm an expert at nothing, but I had to deal with license violations in the Free Software and reported some of them. In fact, I just reported one a few hours ago.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on January 05, 2016, 06:28:50 am
Hi, I am brand new to this forum but an old EE.  I finally decided to order one of these testers.  I would like to use a rechargeable battery instead of the 9V one.  I am planing on using an 18650 Li-Ion with one of these cheap USB PowerBank (<$1 on eBay and I have plenty of these batteries).  These PowerBanks have a small charger for the Li-Ion and a step-up PWM for the 5V output.  My idea is to use the circuit to charge the battery and to replace the linear 5V regulator on the tester.  A fully charged battery will probably last me over a year if it wouldn't self discharge before that.

My question is, the tester monitors the battery voltage on PC5, does it do anything with that information, like shutting down everything if it thinks that the battery voltage is low (Li-Ion is ~3.7V)?  Would I need to reprogram the AVR, or the battery voltage monitoring is just for the user information.

Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 05, 2016, 07:15:37 am
@upsss
Before compiling the new firmware you have to make the necessary changes in the "Makefile":
# To adjust the warning-level and poor-level of battery check to the capability of a
# low drop voltage regulator, you can specify the Option BAT_POOR=5400 .
# The unit for this option value is 1mV , 5400 means a poor level of 5.4V.
# The warning level is 0.8V higher than the specified poor level (>5.3V).
# The warning level is 0.4V higher than the specified poor level (>2.9V, <=5.3V).
# The warning level is 0.2V higher than the specified poor level (>1.3V, <=2.9V).
# The warning level is 0.1V higher than the specified poor level (<=1.3V).
# Setting the poor level to low values is not recommended for rechargeable Batteries,
# because this increase the danger for deep discharge!!
CFLAGS += -DBAT_POOR=2800
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on January 05, 2016, 08:29:47 am
@tom666, so what exactly happens when the battery reaches the "poor level", does the system shuts down?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on January 05, 2016, 09:01:23 am
I am planing on using an 18650 Li-Ion with one of these cheap USB PowerBank (<$1 on eBay and I have plenty of these batteries).  These PowerBanks have a small charger for the Li-Ion and a step-up PWM for the 5V output.  My idea is to use the circuit to charge the battery and to replace with it the linear 5V regulator on the tester.
Yes, you can.
what exactly happens when the battery reaches the "poor level", does the system shuts down?
No, but it doesn't start ;)

All what you need is to get familiar with the makefile options.
Hardware specific there are three point for voltage monitoring:
- voltage divider
- battery/input voltage
- regulator output voltage/VCC

If you connect the LiIon with battery input and the booster output to VCC there is no need for a seperated protection board.

Note:
I've built two testers from DIY M12864 Tester, the 7550 has a drop of 0.1 V only.
I selected a booster for 5.135 V output, connected to BatIn and VCC is 4.99 V, when testing it drops to 4.89 V ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 05, 2016, 04:25:01 pm
@tom666, so what exactly happens when the battery reaches the "poor level", does the system shuts down?

The tester displays a "battery low" message and powers off. For a Li-Ion battery you would have to change/remove the voltage divider (just a single resistor I assume) and the code for the battery check. Simple job.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on January 05, 2016, 04:45:29 pm
Thanks guys, that is exactly what I needed to know.  In the meantime I will probably cheat (I am a hardware guy) and change proportionally the PC5 voltage divider while I order a programmer and learn how to reprogram this thing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 05, 2016, 09:26:00 pm
For a Li-Ion battery you would have to change/remove the voltage divider (just a single resistor I assume) and the code for the battery check.

I do not understand why? How then will test the voltage of the Li-Ion battery?
The voltage divider is needed and there is no reason to change the values of the divider (resistors 10k and 3k3). Attached picture is only for inspiration (power from 2xAA battery or from the USB port).
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on January 05, 2016, 10:05:23 pm
@tom666, you are right if you are going to reprogram the AVR then the sensing voltage divider should stay the same.  What I will do temporarily until I reprogram it, I will change the lower resistor from 3.3k to 15k and that will "fool" the AVR to think that the 3.7V battery is actually 9V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on January 06, 2016, 12:30:01 am
@madires

Sorry if I'm stubborn and boring with that.

Did you read my message about the license?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on January 06, 2016, 04:17:52 am
@madires

Sorry if I'm stubborn and boring with that.

Did you read my message about the license?

I would prefer he doesn't waste his time on utterly shit banal bureaucratic legalese crap and get on with just doing what all hobbyists and enthusiasts have done forevermore. Especially as we already know the fucking Chinese are not in the least bothered with this shit for a $10 transistor tester.

Stop harassing people with your version of what you think is the correct version of open source - go and make something fucking interesting and useful instead, maybe? Then apply your own preferred license to it.  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 06, 2016, 11:11:41 am
For a Li-Ion battery you would have to change/remove the voltage divider (just a single resistor I assume) and the code for the battery check.

I do not understand why? How then will test the voltage of the Li-Ion battery?
The voltage divider is needed and there is no reason to change the values of the divider (resistors 10k and 3k3). Attached picture is only for inspiration (power from 2xAA battery or from the USB port).

The Li-Ion battery got 3.7V which is less than 5V. So you can monitor the battery directly (just protected by a series resistor). Also I would change the ok/weak/low levels to match the Li-Ion battery.

The circuit you've attached doesn't have the MCU controlled power management. If you take the original circuit, adjust some resistor values and insert the boost converter behind the power switching PNP you'll get a nice Li-Ion powered unit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 06, 2016, 11:23:07 am
@madires

Sorry if I'm stubborn and boring with that.

Did you read my message about the license?

Yes, I have. And I'll stay with the EUPL, because that license is exactly what I want.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlessandroAU on January 06, 2016, 12:19:35 pm
Anyone buy one of these from eBay?

http://www.ebay.com.au/itm/381439312402?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com.au/itm/381439312402?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 06, 2016, 12:37:18 pm
The Li-Ion battery got 3.7V which is less than 5V. So you can monitor the battery directly (just protected by a series resistor). Also I would change the ok/weak/low levels to match the Li-Ion battery.

I agree. However, it should make a small modifications in the source code. Otherwise (if used standard voltage divider), just only make the appropriate adjustments in the Makefile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 06, 2016, 04:14:55 pm
I would like to use a rechargeable battery instead of the 9V one.  I am planing on using an 18650 Li-Ion with one of these cheap USB PowerBank (<$1 on eBay and I have plenty of these batteries).  These PowerBanks have a small charger for the Li-Ion and a step-up PWM for the 5V output.  My idea is to use the circuit to charge the battery and to replace the linear 5V regulator on the tester.

Attached pictures (inspired with the Fish8840 tester) contain two possible solutions for the supply with the Li-Ion battery and adjustable voltage boost module. This circuits could be supplemented with a charging module.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on January 07, 2016, 01:22:42 am
With my idea, the Power Bank circuit for <$1 incorporates the charger and the 5v output into one tiny circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on January 09, 2016, 07:08:56 pm
Is the Transistor/Component Tester code easy to port to other similar platforms?

There are interesting chips from Silicon Labs that are 8051 based, too. I causally got for free a C8051F063 one.

I have no clue about programming, but it seems to provide nice ADC and DAC features.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on January 10, 2016, 02:02:01 am
Is the Transistor/Component Tester code easy to port to other similar platforms?

There are interesting chips from Silicon Labs that are 8051 based, too. I causally got for free a C8051F063 one.

I have no clue about programming, but it seems to provide nice ADC and DAC features.

I have only a slight clue about programming, but I'm guessing that, no, it isn't easy to port, since it takes advantage of particulars of AVR hardware. On the other hand, the documentation is quite detailed. A port sounds like a good way to learn something about embedded programming...
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on January 10, 2016, 04:16:47 pm
@Macbeth
@madires

I'm sorry, I didn't want to annoy at all. The real issue is that mixing codes from different licenses is a real mess, that's all. I didn't want to annoy people, just provide feedback.


Is the Transistor/Component Tester code easy to port to other similar platforms?

There are interesting chips from Silicon Labs that are 8051 based, too. I causally got for free a C8051F063 one.

I have no clue about programming, but it seems to provide nice ADC and DAC features.

I have only a slight clue about programming, but I'm guessing that, no, it isn't easy to port, since it takes advantage of particulars of AVR hardware. On the other hand, the documentation is quite detailed. A port sounds like a good way to learn something about embedded programming...


Thanks for the info!

I had a very wrong idea about AVR and 8051. I did think this would be a lot simpler, just like porting an x86 OS to another x86 machine. But thinking about that, there should be "drivers" for the peripherals and such.

I can get more of those chips. If anyone is interested in research about that, he'll get them for free ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 11, 2016, 05:41:40 am
I want to add a relay to the tester to protect it from charged capacitors. Should I include a series resistor to limit the discharge current?
I know that when the "screwdriver method" is used with high energy caps, there is a visible arc, and then damage to the surface of the piece of metal used. Maybe the arcing would eventually destroy the relay contacts, or possibly weld them shut. I think a 1R3 resistor would do the trick.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 11, 2016, 02:36:49 pm
I want to add a relay to the tester to protect it from charged capacitors. Should I include a series resistor to limit the discharge current?
I know that when the "screwdriver method" is used with high energy caps, there is a visible arc, and then damage to the surface of the piece of metal used. Maybe the arcing would eventually destroy the relay contacts, or possibly weld them shut. I think a 1R3 resistor would do the trick.

The relay is just a crude protection. A series resistor limits the current but increases the discharge time, and the delay might be long enough to destroy the MCU. The question is more likely to be whether the MCU or the relay is cheaper. I'd suggest to have a simple process in place to measure the voltage with a DMM and discharge the cap with a resistor before using the Transistortester. This is a good advice anyway when repairing a device.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 12, 2016, 03:45:49 am
How can the rotary encoder be connected to the same pins as the display (PD1/3) without interfering with it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on January 12, 2016, 08:14:34 am
I want to add a relay to the tester to protect it from charged capacitors. Should I include a series resistor to limit the discharge current?
I know that when the "screwdriver method" is used with high energy caps, there is a visible arc, and then damage to the surface of the piece of metal used. Maybe the arcing would eventually destroy the relay contacts, or possibly weld them shut. I think a 1R3 resistor would do the trick.

The relay is just a crude protection. A series resistor limits the current but increases the discharge time, and the delay might be long enough to destroy the MCU. The question is more likely to be whether the MCU or the relay is cheaper. I'd suggest to have a simple process in place to measure the voltage with a DMM and discharge the cap with a resistor before using the Transistortester. This is a good advice anyway when repairing a device.
+1 , without protection an ESR meter would not last long in a real repair scene.  I have burnt a Russian cute tiny ESR 4 times and last time it became non-repairable.  Same to my capacitance meter.  Make it able to withstand 600V, even at 50V, I can retire my Bob Parker ESR.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2016, 09:30:05 pm
How can the rotary encoder be connected to the same pins as the display (PD1/3) without interfering with it?

Careful selection of resistors ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 12, 2016, 10:06:43 pm
Ah. So the 328 and the display respond to different voltage thresholds then?
I still don't understand how the MCU can perform two actions simultaneously on the same pins (such as when scrolling though a menu): receive rotary encoder signals, and send display signals.
Unless ... they are carefully interleaved?

Are there any benefits to connecting the 7565 CS (CE) pin to PD5? The board which came with my kit simply connects it to ground.
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on January 13, 2016, 05:18:02 am
I have a tester listed at

http://www.ebay.com/itm/MK-328-TR-ESR-transistor-inductance-capacitance-resistance-ESR-Tester-/121593935597 (http://www.ebay.com/itm/MK-328-TR-ESR-transistor-inductance-capacitance-resistance-ESR-Tester-/121593935597)

Unfortunately i dropped it and with the impact the LCD FPC tore and came off. I ordered an LCD from

http://www.ebay.com/itm/171324266047?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/171324266047?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

I am not sure but I think this is based on ST7567 . Physically it is an exact fit.

I soldered it carefully.

On pressing the TEST button the backlight comes ON and goes OFF after some time. Nothing is displayed.

I suspect the firmware is corrupt. Can anyone point me to the correct tester.hex and eeprom.hex files for this model ?

The PCB has the following text printed :

EZM Electronics Studio
 MK_328_V1.0
 2014.07.14

Thanks in advance.

And also thanks for a great thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 13, 2016, 08:23:15 am
All the pre-compiled firmware is listed here (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) or here (https://github.com/svn2github/transistortester/tree/master/Software/trunk). You must download the entire directory via the link at the bottom. (Resources provided by Karl-Heinz Kubbeler and others)

I'm not sure which ROM is the correct one, but your unit looks similar to the GM328, and T3/4/5 ST7565 devices. Hopefully someone else will recognize it and chime in. Failing that, the source code is there for you to modify and compile yourself.

Even though your LCD module may be similar physically, there may be differences in pinout or interface. I would double-check those before assuming your firmware is corrupt. Check your datasheet. Karl-Heinz wrote some very detailed documentation (http://www.avrtester.tode.cz/upload/ttester_en.pdf) which you may want to take a look at.

Hope that helps.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 13, 2016, 11:28:42 am
@micro88
Maybe it will help (parts of leanid indman archive (https://yadi.sk/d/yW8xa5NJgUo5z)).

MK-328 Tester:
https://yadi.sk/d/yW8xa5NJgUo5z/Mk-328/Foto (https://yadi.sk/d/yW8xa5NJgUo5z/Mk-328/Foto)
https://yadi.sk/d/yW8xa5NJgUo5z/Mk-328/Firmware (https://yadi.sk/d/yW8xa5NJgUo5z/Mk-328/Firmware)

However, before using the new firmware I recommend to carefully check the LCD connection with the MCU. Especially shortcut between the data signal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 13, 2016, 11:59:24 am
Ah. So the 328 and the display respond to different voltage thresholds then?
I still don't understand how the MCU can perform two actions simultaneously on the same pins (such as when scrolling though a menu): receive rotary encoder signals, and send display signals.
Unless ... they are carefully interleaved?

The mode of the MCU's I/O pins is switched between input (polling the rotary encoder) and output (display output).

Quote
Are there any benefits to connecting the 7565 CS (CE) pin to PD5? The board which came with my kit simply connects it to ground.

If the rotary encoder is connected in parallel to specific LCD pins it might cause some interference. In that case you should drive the LCD's /CS (there are switches in the source code). PD1/PD3 are fine for the rotary encoder without any need for driving /CS.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on January 13, 2016, 12:22:05 pm
I want to add a relay to the tester to protect it from charged capacitors. Should I include a series resistor to limit the discharge current?
I know that when the "screwdriver method" is used with high energy caps, there is a visible arc, and then damage to the surface of the piece of metal used. Maybe the arcing would eventually destroy the relay contacts, or possibly weld them shut. I think a 1R3 resistor would do the trick.

The relay is just a crude protection. A series resistor limits the current but increases the discharge time, and the delay might be long enough to destroy the MCU. The question is more likely to be whether the MCU or the relay is cheaper. I'd suggest to have a simple process in place to measure the voltage with a DMM and discharge the cap with a resistor before using the Transistortester. This is a good advice anyway when repairing a device.
+1 , without protection an ESR meter would not last long in a real repair scene.  I have burnt a Russian cute tiny ESR 4 times and last time it became non-repairable.  Same to my capacitance meter.  Make it able to withstand 600V, even at 50V, I can retire my Bob Parker ESR.

In few days i'll receive the M12864 from Bangood and I was also thinking to add a relay to protect the inputs...
At page 11 of the excellent firmware documentation (http://www.avrtester.tode.cz/upload/ttester_en.pdf (http://www.avrtester.tode.cz/upload/ttester_en.pdf)) is it clearly described how to add protections with relay or diodes.
Personally I prefer the relay and since the contacts are normally closed, when the charged capacitor is connected, the spark should occur at the capacitor lead touching the probes and not at the relay contacts.

Or, since I ordered also the case, I will glue on a side a small piece of metal and will discharge the capacitors on it before the measurement :)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on January 13, 2016, 01:10:05 pm
@micro88
Maybe it will help (parts of leanid indman archive (https://yadi.sk/d/yW8xa5NJgUo5z)).

MK-328 Tester:
https://yadi.sk/d/yW8xa5NJgUo5z/Mk-328/Foto (https://yadi.sk/d/yW8xa5NJgUo5z/Mk-328/Foto)
https://yadi.sk/d/yW8xa5NJgUo5z/Mk-328/Firmware (https://yadi.sk/d/yW8xa5NJgUo5z/Mk-328/Firmware)

However, before using the new firmware I recommend to carefully check the LCD connection with the MCU. Especially shortcut between the data signal.

Thanks a lot tom666. I tried loading that firmware. Now I am getting some black horizontal and vertical dotted lines on the screen when I press the TEST button. As you said I will check the LCD connections carefully.

Thanks once again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on January 13, 2016, 10:22:28 pm
I want to add a relay to the tester to protect it from charged capacitors. Should I include a series resistor to limit the discharge current?
I know that when the "screwdriver method" is used with high energy caps, there is a visible arc, and then damage to the surface of the piece of metal used. Maybe the arcing would eventually destroy the relay contacts, or possibly weld them shut. I think a 1R3 resistor would do the trick.

The relay is just a crude protection. A series resistor limits the current but increases the discharge time, and the delay might be long enough to destroy the MCU. The question is more likely to be whether the MCU or the relay is cheaper. I'd suggest to have a simple process in place to measure the voltage with a DMM and discharge the cap with a resistor before using the Transistortester. This is a good advice anyway when repairing a device.
+1 , without protection an ESR meter would not last long in a real repair scene.  I have burnt a Russian cute tiny ESR 4 times and last time it became non-repairable.  Same to my capacitance meter.  Make it able to withstand 600V, even at 50V, I can retire my Bob Parker ESR.
Oh, advices and procedures. My favorite way of breaking things. I'm working on avoiding it, trying to workaround that bug on me ;)


That's how I break DMMs, so I dream to have a good one of those that advices me to not use the incorrect sockets and even blocking them physically. But I don't understand why DMMs can't use some solid state switching for that (added resistance?) [emoji14]

Would a fine way be too complex to implement? Foolproof, absent minded people that forget things quite often ;)

I asked in the German forum about newer hardware project files. It would be nice to do an Open Hardware contest for it. I myself would like to try to do it both in OrCAD and KiCad, if my mind gets in better shape ;)

What would be the better AVR to be supported?
I want to add a relay to the tester to protect it from charged capacitors. Should I include a series resistor to limit the discharge current?
I know that when the "screwdriver method" is used with high energy caps, there is a visible arc, and then damage to the surface of the piece of metal used. Maybe the arcing would eventually destroy the relay contacts, or possibly weld them shut. I think a 1R3 resistor would do the trick.

The relay is just a crude protection. A series resistor limits the current but increases the discharge time, and the delay might be long enough to destroy the MCU. The question is more likely to be whether the MCU or the relay is cheaper. I'd suggest to have a simple process in place to measure the voltage with a DMM and discharge the cap with a resistor before using the Transistortester. This is a good advice anyway when repairing a device.
+1 , without protection an ESR meter would not last long in a real repair scene.  I have burnt a Russian cute tiny ESR 4 times and last time it became non-repairable.  Same to my capacitance meter.  Make it able to withstand 600V, even at 50V, I can retire my Bob Parker ESR.
Oh, advices and procedures. My favorite way of breaking things. I'm working on avoiding it, trying to workaround that bug on me ;)


That's how I break DMMs, so I dream to have a good one of those that advices me to not use the incorrect sockets and even blocking them physically. But I don't understand why DMMs can't use some solid state switching for that (added resistance?) [emoji14]

Would a fine way be too complex to implement? Foolproof, absent minded people that forget things quite often ;)

I asked in the German forum about newer hardware project files. It would be nice to do an Open Hardware contest for it. I myself would like to try to do it both in OrCAD and KiCad, if my mind gets in better shape ;)

What would be the better AVR to be supported?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2016, 11:57:48 am
I asked in the German forum about newer hardware project files. It would be nice to do an Open Hardware contest for it. I myself would like to try to do it both in OrCAD and KiCad, if my mind gets in better shape ;)

What would be the better AVR to be supported?

The ATmega 664 or 1284. There's a circuit in Karl-Heinz' documentation but I think it would be a good idea to change some I/O pins to be more flexible with future extensions and options. My idea is to have a complete port just for the display which allows to have a SPI with 2 or 3 /CS and an interrupt input. That would be nice for a graphics LCD, touchscreen and some other SPI device (SD card, GPIO?).
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on January 14, 2016, 10:16:08 pm
I asked in the German forum about newer hardware project files. It would be nice to do an Open Hardware contest for it. I myself would like to try to do it both in OrCAD and KiCad, if my mind gets in better shape ;)

What would be the better AVR to be supported?

The ATmega 664 or 1284. There's a circuit in Karl-Heinz' documentation but I think it would be a good idea to change some I/O pins to be more flexible with future extensions and options. My idea is to have a complete port just for the display which allows to have a SPI with 2 or 3 /CS and an interrupt input. That would be nice for a graphics LCD, touchscreen and some other SPI device (SD card, GPIO?).


OH, NICE!

Did you look at this?

https://www.youtube.com/watch?v=CmaFNkuQgNQ (https://www.youtube.com/watch?v=CmaFNkuQgNQ)
https://www.youtube.com/watch?v=CTH_VzWOI1Y (https://www.youtube.com/watch?v=CTH_VzWOI1Y)
https://www.youtube.com/watch?v=j810jJO3k-0 (https://www.youtube.com/watch?v=j810jJO3k-0)
https://www.youtube.com/watch?v=bTg2oSPBGUw (https://www.youtube.com/watch?v=bTg2oSPBGUw)
https://www.youtube.com/watch?v=3mOs3BuY7OY (https://www.youtube.com/watch?v=3mOs3BuY7OY)
https://www.youtube.com/watch?v=x-u-OlXEIR8&spfreload=10 (https://www.youtube.com/watch?v=x-u-OlXEIR8&spfreload=10) https://www.youtube.com/watch?v=Tz8Jzf2PFog (https://www.youtube.com/watch?v=Tz8Jzf2PFog)  https://www.youtube.com/watch?v=COznTZYp8K4&spfreload=10 (https://www.youtube.com/watch?v=COznTZYp8K4&spfreload=10)  https://www.youtube.com/watch?v=bTg2oSPBGUw (https://www.youtube.com/watch?v=bTg2oSPBGUw)   http://www.drviragopete.com/electronic-parts-testing-service.php (http://www.drviragopete.com/electronic-parts-testing-service.php)  http://www.tauntek.com/LogICTester-low-cost-logic- (http://www.tauntek.com/LogICTester-low-cost-logic-)
chip-tester.htm https://www.youtube.com/watch?v=Y7aORrJmPE4&spfreload=10 (https://www.youtube.com/watch?v=Y7aORrJmPE4&spfreload=10) https:
//www.youtube.com/watch?v=IeZEP1OKqy8
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 15, 2016, 06:24:38 am
@timofonic and other users
Please, do not use complet quotes unnecessarily!
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on January 16, 2016, 01:55:37 pm
@tom666

Happy to inform that I finally got the tester to work by repairing a broken PCB track. I also used the makefile from your link and compiled the required firmware for MK-328 model of the tester.

Thanks a million for your help.

Cheers and best wishes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 16, 2016, 08:09:32 pm
@micro88

I am very happy that it works again :)

Best regards
Tom
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on January 21, 2016, 07:23:09 pm
Hi, will this encoder work with this tester?  It doesn't say that it has a switch but I think all of them have one and I can see it has 5 pins. http://www.ebay.com/itm/Rotary-Encoder-Module-Brick-Sensor-Development-Board-Test-For-Arduino-New-GU-/371451401545?hash=item567c3a9549:g:hIoAAOSwVL1WCV1O (http://www.ebay.com/itm/Rotary-Encoder-Module-Brick-Sensor-Development-Board-Test-For-Arduino-New-GU-/371451401545?hash=item567c3a9549:g:hIoAAOSwVL1WCV1O)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2016, 03:17:03 pm
Hi, will this encoder work with this tester?  It doesn't say that it has a switch but I think all of them have one and I can see it has 5 pins. http://www.ebay.com/itm/Rotary-Encoder-Module-Brick-Sensor-Development-Board-Test-For-Arduino-New-GU-/371451401545?hash=item567c3a9549:g:hIoAAOSwVL1WCV1O (http://www.ebay.com/itm/Rotary-Encoder-Module-Brick-Sensor-Development-Board-Test-For-Arduino-New-GU-/371451401545?hash=item567c3a9549:g:hIoAAOSwVL1WCV1O)

Should be fine! And note the two 10k resistors already on the PCB.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on January 22, 2016, 04:56:38 pm
Thanks, one more thing.  Do you or anyone else know, does this one have the code builtin for the rotary encoder or I have to re flash the AVR?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2016, 05:40:27 pm
Thanks, one more thing.  Do you or anyone else know, does this one have the code builtin for the rotary encoder or I have to re flash the AVR?

I'd assume that you have to compile the firmware with the rotary encoder option enabled and re-flash.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ryanna on January 23, 2016, 10:49:09 am
Hi Tom666,

My parts just arrived and iam trying to follow your instructions but iam having problems, i think i need the hex and eep files also some errors in setting clk please see attaced photos, can you help me find the problem or files needed.

Thanks,

@ryanna

Procedure for flashing firmware:

Required hardware:
- USBasp programmer (http://www.ebay.com/itm/USBASP-USBISP-AVR-Programmer-Adapter-10-Pin-Cable-USB-ATMEGA8-ATMEGA128-Arduino-/310506909410) (price around US $1.87)
- AVR Development Board (http://www.ebay.com/itm/ATMEGA8-ATMEGA48-ATMEGA88-Development-Board-AVR-NO-Chip-DIY-Kit-/291550040876) (price around US $1.55) - or other AVR ISP adapter

Note:
Alternatively, it can use USBasp with a breadboard (for example 400 pin) - see attached picture.

Required Software (download links below):
- USBasp Driver
- AVRDUDE
- Firmware

1. Unzip the downloaded files into a separate directory and then perform installation of the USBasp driver.
2. Then remove MCU from the socket and insert it into the AVR ISP adapter.
3. Through the ISP cable connect the USBasp programmer with the ISP connector on the AVR ISP adapter.
4. Navigate to the folder with the unpacked software and perform this following command from command line:
   avrdude -c usbasp -p m328p -B 4.0 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m
   This command (also includes a section for writing fuses) can be copied and saved as e.g. "flash.bat" and stored in a prepared folder. In the future you can simplify this flashing of the firmware by the usage of "flash.bat".
5. After, if MCU is successfully burned, fit it back into the socket of the tester.
6. The first time the tester is suitable to calibrate. The procedure can be found in the manual.

Links:
USBasp - Driver:
http://www.fischl.de/usbasp/usbasp-windriver.2011-05-28.zip (http://www.fischl.de/usbasp/usbasp-windriver.2011-05-28.zip)
or
http://www.protostack.com/download/USBasp-win-driver-x86-x64-v3.0.7.zip (http://www.protostack.com/download/USBasp-win-driver-x86-x64-v3.0.7.zip)

AVRDUDE:
http://download.savannah.gnu.org/releases/avrdude/avrdude-6.1-mingw32.zip (http://download.savannah.gnu.org/releases/avrdude/avrdude-6.1-mingw32.zip)

Firmware:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/?view=tar)

USBasp - How to install driver on Windows 8:
http://letsmakerobots.com/node/36841 (http://letsmakerobots.com/node/36841)

USBasp - How to install driver on Windows 8.1:
http://openchrysalis.wordpress.com/2014/09/26/installing-usbasp-driver-software-in-windows-8-1/ (http://openchrysalis.wordpress.com/2014/09/26/installing-usbasp-driver-software-in-windows-8-1/)

USBasp - User Guide:
http://www.protostack.com/download/Users%20Guide%20(AC-PG-USBASP-UG-V2.0).pdf (http://www.protostack.com/download/Users%20Guide%20(AC-PG-USBASP-UG-V2.0).pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 23, 2016, 04:42:49 pm
@ryanna
Hi,
warning "cannot set SCK period ..." is associated with an older version of the firmware. But it should not have a negative impact for the programming process.
The latest firmware and the updating procedure are available on:
http://www.fischl.de/usbasp/ (http://www.fischl.de/usbasp/)

Files "TransistorTester.hex" and "TransistorTester.eep" (included in the archive at the following link) must be placed in the folder with the program avrdude. In your case, it is the directory "C:\esrmeter\".
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/?view=tar (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_2X16_menu/?view=tar)
Title: Re: $20 LCR ESR Transistor checker project
Post by: demetris on January 23, 2016, 08:16:33 pm
Hello guys,
I have an m168 with smd parts i was able to flash 1.21m classic but capacitors are only shown capacitance NO ESR values.
I only care for inline circuit measurements of capacitors and maybe some offline too plus if* possible transistors/mosfets.
Tried the 1.11k but prints cell! and is unusable.
I tried edit config.h in ComponentTester-classic-1.21m but there is no define SW_ESR option for < 32kB Flash
Please help me out if possible, my equipment is the standard mcu atmega168 with the classic 2x16 screen
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 23, 2016, 08:38:39 pm
I tried edit config.h in ComponentTester-classic-1.21m but there is no define SW_ESR option for < 32kB Flash
Please help me out if possible, my equipment is the standard mcu atmega168 with the classic 2x16 screen

Simply add "#define SW_ESR" at the bottom of config.h. You also need to change MENU_ITEMS from 5 to 6 in function PresentMainMenu() in user.c. But I don't know if the firmware will be small enough for the ATmega168.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 23, 2016, 09:56:11 pm
I have an m168 with smd parts ...
Tried the 1.11k but prints cell! and is unusable.
... my equipment is the standard mcu atmega168 with the classic 2x16 screen

If you own tester as shown in the attached picture, you need make for eliminate the problem with the message "cell!" modification of the hardware as recommended by the software author (Karl-Heinz Kübbeler). Modification consists in adding the additional blocking capacitor 100nF between Pin 18 (AVCC) and Pin 21 (GND) the MCU. Detail info can be found in the official manual (the relevant part of the manual is attached). However, if you want to fully exploit the capabilities of the software I recommend replacing the MCU (M328).
Title: Re: $20 LCR ESR Transistor checker project
Post by: demetris on January 23, 2016, 10:30:45 pm
@tom666
Yes that is exactly my pcb, thank you for your  help on this.
Am not good at soldering so i cannot change the mcu as it has very small connections.
@madires
Are you sure is MENU_ITEMS 5->6 and not 5->8?
As i can see in user.c says define SW_ESR MenuID[Item] = 8; and next:
#ifdef SW_ESR
    case 8:              /* ESR tool */
      ESR_Tool();
      break;
    #endif

i have compiled it and hex is 45.9 kB (45909 bytes) is ok right?
These are my settings in config.h
//#define HW_ENCODER
//#define ENCODER_PULSES   2
//#define HW_REF25
#define UREF_25           2495
//#define HW_RELAY
//#define HW_ZENER
//#define HW_FREQ_COUNTER
and finally:
#define SW_ESR
Is here anything that needs to be enable/disable and its not?
Thank you for the help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ryanna on January 24, 2016, 10:11:57 am
Hi Tom,

Thanks but iam not able to open the second link, it give me time out error, do you have other links?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 24, 2016, 01:23:23 pm
@ryanna
Hi,
mirror of the SVN archive is at:
https://github.com/svn2github/transistortester

Attached zip file contains only the contents of the appropriate directory "mega328_2X16_menu".
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 24, 2016, 03:04:21 pm
Are you sure is MENU_ITEMS 5->6 and not 5->8?
As i can see in user.c says define SW_ESR MenuID[Item] = 8; and next:

Code: [Select]
#ifdef SW_ESR
    case 8:              /* ESR tool */
      ESR_Tool();
      break;
    #endif

6 is correct. 8 is just an internal ID to identify the menu item.

Quote
i have compiled it and hex is 45.9 kB (45909 bytes) is ok right?

The compiler gives you the actual size of the binary firmware which shouldn't exceed 16k for ATmega 168. If it does you'd need to disable something else. The hex file is always larger because it's the firmware encoded in Intel format.

Quote
These are my settings in config.h

Code: [Select]
//#define HW_ENCODER
//#define ENCODER_PULSES   2
//#define HW_REF25
#define UREF_25           2495
//#define HW_RELAY
//#define HW_ZENER
//#define HW_FREQ_COUNTER
and finally:
#define SW_ESR

Is here anything that needs to be enable/disable and its not?
Thank you for the help.

That looks fine!
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on January 25, 2016, 03:43:34 pm
Hello again,

I have been trying to compare the performance of two different testers purchased from ebay China.

The MK328 which I managed to repair as mentioned earlier and the other is GM328A purchased from
http://www.ebay.com/itm/Digital-GM328A-Transistor-Tester-ESR-Meter-Frequency-Square-Wave-Generator-V2PP-/201479185670?hash=item2ee9186506:g:U24AAOSwbdpWYnJc (http://www.ebay.com/itm/Digital-GM328A-Transistor-Tester-ESR-Meter-Frequency-Square-Wave-Generator-V2PP-/201479185670?hash=item2ee9186506:g:U24AAOSwbdpWYnJc)

I tested a 2N3055 power transistor on both with emitter on 1, base on 2 and collector on 3
The results differed . The GM328A detected the pinout correctly while the MK328 shows interchanged collector and emitter.
Also hfe shown differs by a factor of 2.

I am trying to figure out why the MK328 is showing wrong pinout.

I have attached the results displayed.

Any comments are welcome with thanks in advance.

Cheers.

 

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 25, 2016, 04:13:10 pm
I am trying to figure out why the MK328 is showing wrong pinout.

Which firmware versions do the testers run?
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on January 26, 2016, 03:15:16 am
@madires

Both testers show 1.12k after selftest.

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 26, 2016, 03:44:51 pm
Both testers show 1.12k after selftest.

The version with the symbol at the top left is a little bit more recent (1.12k is the current version under development) but I have no idea why C and E are swapped.
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on January 26, 2016, 04:16:46 pm
I tested a few other transistors and found that some of them like BC547 and SL100 show similar behavior on both the testers. While for some transistors like 2N3055 the MK328 swaps the collector and emitter. Will post here if I am able to resolve it.

Thanks once again.
Best regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on January 26, 2016, 05:31:06 pm
Are you sure the battery on both testers is good?  In any case, I would verify the input and output voltage on the 5V regulator on both units while testing.  If the differential voltage is less than 2V, I would replace the battery.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 26, 2016, 05:40:24 pm
I tested a few other transistors and found that some of them like BC547 and SL100 show similar behavior on both the testers. While for some transistors like 2N3055 the MK328 swaps the collector and emitter. Will post here if I am able to resolve it.

Have you run the self-adjustment on both testers? One possible cause could be detection process for BJTs. It's run for C-E and C-E while the correct pinout is determined by the higher hFE.
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on January 27, 2016, 03:43:39 am
@madires and @upsss

I have run the self test on both the testers. In fact there is no problem with the GM328A. Also the batteries used are new and 5V measures 4.98V. The only hardware change which I made to MK328 is that I had to remove the connection of the TL431 regulator to pin PC4 of the processor because I found that if I keep it connected the output of TL431 goes to zero. So I concluded that there is something wrong with PC4 which is loading the TL431 .

May be I should replace the Atmega328. I shall try that once I get a good hot air gun and a new smd chip.

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: speedy29 on January 28, 2016, 05:34:13 pm
Help, I need to figure out which os install on ATMEL 328, since I was spoiled the processor.
Attaching photos of the device
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 29, 2016, 07:04:29 am
@speedy29
In the attached file you can find the necessary :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: speedy29 on January 29, 2016, 08:32:56 am
Grazie ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on January 29, 2016, 08:50:54 am
Di niente :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on January 29, 2016, 04:05:23 pm
@madires

Hola.

I'm sorry a lot for my spasm!

Thanks a lot to you and the rest of the Component (can we call it this way?) Tester Team.

How much people collaborate on in this great project? i Are you all the from Germany?

You can ignore my stupid questions, I'm sure they can be foolish for people enough skilled in electronics. I would love to do versatile abs and smart projects like this someday! Perfect to make the life easier ofr both professionals and I aficionados and economical. Electronics needs more great DIY stuff like this!

I appreciate your incredible effort if all of you!

I'm sure you are busy to reply stupid things.

Did you see that component tester that showed waveforms?

About the (transistor) component tester :

If having a bigger uC:

- Do transistors and certain components have known characteristics that could be identified to know the model despite the code might be erased?

- Could the data sheets be transcribed and redone in saved in a database and compare the results to show the possible model?
* Of course, by crowdsourcing this daunting job of collecting information and using a converter to the very low overhead file format.

 I know it's a crazy and probably impossible idea, but I'm curious about how difficult would be to achieve that by community contributions.

Do you think the IC tester from Chinese would be easy to replicate? I suppose the software would be more difficult than the hardware.


Danke!
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on January 29, 2016, 04:24:58 pm
Just received and assembled my DIY M12864 from Banggood!!!!
It is great and I'm really impressed by its capabilities, hats off to everyone who contributed to this amazing project  :clap: :clap: :clap:

It came with and old k firmware and to upgrade it I've added the ICSP connector (see pictures).

I've noticed a difference in the measurement using different firmware:

The 1.12k 523 and 1.12k 555 seems to be fine and the 220nF that came with the kit measure 217.2nF ESR=.29?
The 1.12k 629 (latest) it measure all the capacitors way low and the 220nF became 165.7nF ESR=.11?

I'm performing the calibration each time I load a new firmware but i think I'm doing something wrong.

It could be the fuses?? please see the attached picture.

I've noticed also that it fails to identify TRIACs is this a known bug??

Thanks
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 29, 2016, 04:46:37 pm
How much people collaborate on in this great project? i Are you all the from Germany?

Karl-Heinz (k-firmware) and me (m-firmware), plus a few helping with support (like tom666), donating hardware (PCBs or clones) and providing some code ideas. Karl-Heinz and I are Germans.

Quote
If having a bigger uC:

- Do transistors and certain components have known characteristics that could be identified to know the model despite the code might be erased?

- Could the data sheets be transcribed and redone in saved in a database and compare the results to show the possible model?
* Of course, by crowdsourcing this daunting job of collecting information and using a converter to the very low overhead file format.

 I know it's a crazy and probably impossible idea, but I'm curious about how difficult would be to achieve that by community contributions.

Do you think the IC tester from Chinese would be easy to replicate? I suppose the software would be more difficult than the hardware.

It might be possible to determine a class like small signal or power transistor, but nothing specific. The tester can't distinguish a BJT built for RF applications from a general purpose small signal one, for example. Detecting or testing ICs is a completely different story. You would need several voltages for power supply and signals. Some universal programmers can do that. Additional I/O pins would be used more likely for a frequency counter prescaler and some other hardware options, but not for testing ICs. And it's essential to have a 5V MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 29, 2016, 04:56:40 pm
I've noticed a difference in the measurement using different firmware:

The 1.12k 523 and 1.12k 555 seems to be fine and the 220nF that came with the kit measure 217.2nF ESR=.29?
The 1.12k 629 (latest) it measure all the capacitors way low and the 220nF became 165.7nF ESR=.11?

I don't see any possible cause for that. Maybe Karl-Heinz got an idea.

Quote
I've noticed also that it fails to identify TRIACs is this a known bug??

None at all or a few specific ones? Some TRIACs can't be detected because the tester's trigger voltage/current is too low.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on January 29, 2016, 05:24:08 pm
How much people collaborate on in this great project? i Are you all the from Germany?

Karl-Heinz (k-firmware) and me (m-firmware), plus a few helping with support (like tom666), donating hardware (PCBs or clones) and providing some code ideas. Karl-Heinz and I are Germans.

Quote
If having a bigger uC:

- Do transistors and certain components have known characteristics that could be identified to know the model despite the code might be erased?

- Could the data sheets be transcribed and redone in saved in a database and compare the results to show the possible model?
* Of course, by crowdsourcing this daunting job of collecting information and using a converter to the very low overhead file format.

 I know it's a crazy and probably impossible idea, but I'm curious about how difficult would be to achieve that by community contributions.

Do you think the IC tester from Chinese would be easy to replicate? I suppose the software would be more difficult than the hardware.

It might be possible to determine a class like small signal or power transistor, but nothing specific. The tester can't distinguish a BJT built for RF applications from a general purpose small signal one, for example. Detecting or testing ICs is a completely different story. You would need several voltages for power supply and signals. Some universal programmers can do that. Additional I/O pins would be used more likely for a frequency counter prescaler and some other hardware options, but not for testing ICs. And it's essential to have a 5V MCU.
Thanks a lot for your charm and learning message! I don't deserve it...

Only two are the main brains of this project? I'm impressed!

Would you both consider in promoting it to attract newcomers? Are you using German in the project?

Would you consider to have a dedicated project site with collaborators summarizing three project in blog posts? :)

So making that would be a very complex and big beast, very probably lots of research, brainstorming, design, prototyping and an expensive BoM. Would you a good filtered SMPS simplify it or there are lots more to take into account?

Am I right in something? Feel free to comment it if you want, I want to learn :)

What can be the reason of not adding IC testing? Too much complexity? Too much pins? Do you consider it out of the scope of the project and would be better to be a separate project? More interest in checking analog components?

I sorry, my ignorance made me unable to understand it! And I just learned a tiny amount of it! I wasn't enough aware of the complexity of specialized electronics, I'm starting to understand this is a current universe!

Thanks for your reasonings: They are inspirational, motivational and didactic. I must study a lot harder!

This reminds me to Inductive Chain Learning, Constructivism and Active Learning :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on January 31, 2016, 03:32:06 pm
I've noticed a difference in the measurement using different firmware:

The 1.12k 523 and 1.12k 555 seems to be fine and the 220nF that came with the kit measure 217.2nF ESR=.29?
The 1.12k 629 (latest) it measure all the capacitors way low and the 220nF became 165.7nF ESR=.11?

I don't see any possible cause for that. Maybe Karl-Heinz got an idea.

Quote
I've noticed also that it fails to identify TRIACs is this a known bug??

None at all or a few specific ones? Some TRIACs can't be detected because the tester's trigger voltage/current is too low.

Hi madires, thank you for the feedback :)
I made few tests flashing different firmware but I'm getting the same strange values with the latest build.
Tomorrow I'll make some other attempts…

Note the usual repository
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)
is no longer available and now I'm using the mirror on
https://github.com/svn2github/transistortester (https://github.com/svn2github/transistortester)

Regarding the Triacs, i tested 4 similar variants and got the same result:

Model   ohm
BTA06  75.5
BTA12 100.3
BTB12  69.6
BTB16 83.6

Most probably current/voltage are too low.

Edit:
Do you happen to have the m-firmware compiled for the M12864 Banggood kit??
In the next days I'll put together the toolchain to built it.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 01, 2016, 11:55:08 am
Regarding the Triacs, i tested 4 similar variants and got the same result:
Model   ohm
BTA06  75.5
BTA12 100.3
BTB12  69.6
BTB16 83.6

Most probably current/voltage are too low.

Yes, I can confirm that BTA12 or BTA16 aren't detected. TIC206 or Z0402 are fine.


Edit:
Do you happen to have the m-firmware compiled for the M12864 Banggood kit??
In the next days I'll put together the toolchain to built it.

I've put the display setup into config.h, but I have no feedback yet. You also have to change the I/O pins for the rotary encoder in config.h (ENCODER_A, ENCODER_B) from PD2/PD3 to PD1/PD3.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 01, 2016, 02:57:57 pm
Hi madires,
    I modified the config.h uncommenting the M12864 DIY display section, commenting the previously selected one and changing the ENCODER_A from PD2 to PD1.

The result is strange, the eep file is too big..., please see files below(I had to rename the ComponentTester.eep to ComponentTester_eep.hex, forum restriction file format...).

Out of curiosity, is it possible to get the results of the tests on the UART??

Thanks
Mauro

Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 02, 2016, 11:21:37 am
On the documentation I found the option to enable the UART!!
Tomorrow I'll have few minutes to play with it.
Will let you know :)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 02, 2016, 03:21:23 pm
Hi madires,
    I modified the config.h uncommenting the M12864 DIY display section, commenting the previously selected one and changing the ENCODER_A from PD2 to PD1.

The result is strange, the eep file is too big..., please see files below(I had to rename the ComponentTester.eep to ComponentTester_eep.hex, forum restriction file format...).

Out of curiosity, is it possible to get the results of the tests on the UART??

What's strange exactly? The hex files are always larger than the binaries because they are encoded in Intel format. The compiler's ouput gives you the real size:

Code: [Select]
AVR Memory Usage
----------------
Device: atmega328

Program:   23944 bytes (73.1% Full)
(.text + .data + .bootloader)

Data:        184 bytes (9.0% Full)
(.data + .bss + .noinit)

EEPROM:      739 bytes (72.2% Full)
(.eeprom)

The m-firmware doesn't support the soft UART (yet?).
Title: Re: $20 LCR ESR Transistor checker project
Post by: i_cant_read on February 02, 2016, 07:29:12 pm
Hi everyone!
Someone might have asked that already in this threat but what is in your opinion the best one out of those many versions?
Thanks for your replies! :)
Greetings,
Jannis
Title: Re: $20 LCR ESR Transistor checker project
Post by: opty on February 02, 2016, 08:01:18 pm
Hi everyone!
Someone might have asked that already in this threat but what is in your opinion the best one out of those many versions?
Thanks for your replies! :)
Greetings,
Jannis

!!!MOST important read ttester.pdf and other info!!! from
http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/)

-> ttester.pdf 2.5 Chinese clones
and some hints on modding (better voltage ref; docoupling cap; etc.)

Then in my opinion (without particular order)
* ATMega328 (some have 168); I prefer socketed atmega just in case I need to replace (never actually happened ;) )
* SPI area for in socket updating (although not that necessary if proc is in socket)
* 16x2 lcd - you don't need those fancy clones; just use standard software (and upgrades) from http://www.mikrocontroller.net (http://www.mikrocontroller.net)
* watch our for cheap mods
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 02, 2016, 11:43:47 pm
SOLVED_1!!! "Different values with different firmwares"
Thank you madires, answering to my latest question you gave me the hint to clear the mistery of the incorrect measurement with different firmware versions:
I'm using the TL866A to upload the firmware and I wasn't  noticing that by default it loads correctly the .hex files as INTEL HEX, but the .eep files as BINARY!!!
Basically I was loading garbage on the data memory and only by accident the older versions where measuring correctly  :palm:

SOLVED_2!! "m-firmware .eep file too big"
Same as before, loading the .eep file as INTEL HEX it actually fit on the eeprom and the m-firmware is now up and running  :-+
I noticed that the text alignament on the screen is not perfect and there are some dots on the left of the screen (see attachment).
I'll verify the config.h and make file...

SOLVED_3!! "TRIACs not identified"
Just to prove the point I tested some other TRIACS and found one that is correctly identified (no PN  :( )

ON Going "UART"
Is it too late to do it now...

I attached a picture of the case I modified to accomodate the ZIF.
I hate the white connector that came with the enclosure and I much prefer the ZIF!!
Yes I made my custom faceplate  :)

Thanks
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on February 03, 2016, 12:14:02 am
First I want to thanks the hero here that are improving the tester almost non-stop.  I better don't mention names as likely I shall left out some.
I bought 3 LCR ESR testers so far.  There is a LCR-T6 just released that has the IR receivers.   I have not updated and upgraded my sets as I was and still waiting for the best time to do the upgrade   :-DD .  But the LCR-T6 still does not have the encoder and likely without the relay so I am going to skip. 
Has anyone modified a LCR-T5 or LCR-T4 or any other china $20 tester to include the encoder and the relay protection?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 03, 2016, 01:11:48 pm
SOLVED_2!! "m-firmware .eep file too big"
Same as before, loading the .eep file as INTEL HEX it actually fit on the eeprom and the m-firmware is now up and running  :-+
I noticed that the text alignament on the screen is not perfect and there are some dots on the left of the screen (see attachment).
I'll verify the config.h and make file...

Glad you found the cause. Please try to enable or disable "#define LCD_OFFSET_X" in the M12864 section in config.h. The ST7565 uses 132 columns internally while the display has just 128 columns. The option above shifts the display output by 4 pixels which is often needed when the output is vertically flipped.
Title: Re: $20 LCR ESR Transistor checker project
Post by: demetris on February 03, 2016, 07:48:27 pm
@all_share can you share some info on the protection relay you are talking about?
Will it help with charged capacitors not blowing out the tester/soc?
Title: Re: $20 LCR ESR Transistor checker project
Post by: garnix on February 03, 2016, 09:28:00 pm


I attached a picture of the case I modified to accomodate the ZIF.
I hate the white connector that came with the enclosure and I much prefer the ZIF!!
Yes I made my custom faceplate  :)


May I ask how you fixated the ZIF on the case? Just glued it on? And then you just soldered some wires to the PCB?

I ordered the same board and case, so I might do a similar modification ;-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Seekonk on February 03, 2016, 09:39:52 pm
I just bought one of these $12 wonders to use at my camp which is 12V.  Tested a capacitor and the value was close, but the ESR read 18 ohms.  Choose a lot of different value caps (other than electrolytics) and it is still 18 ohms.  Place a 51 ohm resistor in series with the cap and it is still reads 18 ohms. Actually, this is about what I expected.  I think it is a very handy device.  Just don't take the numbers too seriously.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on February 03, 2016, 10:48:27 pm
I just bought one of these $12 wonders to use at my camp which is 12V.  Tested a capacitor and the value was close, but the ESR read 18 ohms.  Choose a lot of different value caps (other than electrolytics) and it is still 18 ohms.  Place a 51 ohm resistor in series with the cap and it is still reads 18 ohms. Actually, this is about what I expected.  I think it is a very handy device.  Just don't take the numbers too seriously.
Or consider you have a faulty unit!  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 03, 2016, 11:18:30 pm
@madires:
Yep, commenting the line #define LCD_OFFSET_X , the LCD allignament is fine, thank you!!

@demetris:
At page 11 of the excellent firmware documentation (http://www.avrtester.tode.cz/upload/ttester_en.pdf (http://www.avrtester.tode.cz/upload/ttester_en.pdf)) is it clearly described how to add protections with relay or diodes.

@garnix:
NO GLUE/WIRES THANK YOU!!!!  :) :) See attached few pictures of the super easy mod.
I have to say that even though I like to have the possibility to easily replace the ZIF also with something different like an SMD adapter, I think I will lower it and cut the edge of the case like the LCR-T6 (see picture)

See attached the list of all the changes I made so far on the config.h to have my M12864 DIY KIT (Banggood) working almost perfectly with the m-firmware.
I wrote almost perfectly, because the "Adjustment" option fail and I dont know why. I'll do some other tests....
Now I'm going back to the k-firmware to play with the UART :)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Seekonk on February 04, 2016, 04:30:31 pm
I just bought one of these $12 wonders to use at my camp which is 12V.  Tested a capacitor and the value was close, but the ESR read 18 ohms.  Choose a lot of different value caps (other than electrolytics) and it is still 18 ohms.  Place a 51 ohm resistor in series with the cap and it is still reads 18 ohms. Actually, this is about what I expected.  I think it is a very handy device.  Just don't take the numbers too seriously.
Or consider you have a faulty unit!  :-//

I contend that any ESR reading of a capacitor below 1uF with these devices is bogus.
Again, I measured a .33uf capacitor with a 51 ohm resistor.  It read 2.2 ohms without
the resistor and 14 ohms with the resistor.  On another machine it read 1 ohm and 53
ohms respectivly as it should.  I invite everyone to make similar tests with a variety
of capacitor values.  I suggest these programs surpress ESR readings on the display
beyond certain values since they have no relation to reality.
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on February 04, 2016, 05:26:29 pm
I just bought one of these $12 wonders to use at my camp which is 12V.  Tested a capacitor and the value was close, but the ESR read 18 ohms.  Choose a lot of different value caps (other than electrolytics) and it is still 18 ohms.  Place a 51 ohm resistor in series with the cap and it is still reads 18 ohms. Actually, this is about what I expected.  I think it is a very handy device.  Just don't take the numbers too seriously.
Or consider you have a faulty unit!  :-//

I contend that any ESR reading of a capacitor below 1uF with these devices is bogus.
Again, I measured a .33uf capacitor with a 51 ohm resistor.  It read 2.2 ohms without
the resistor and 14 ohms with the resistor.  On another machine it read 1 ohm and 53
ohms respectivly as it should.  I invite everyone to make similar tests with a variety
of capacitor values.  I suggest these programs surpress ESR readings on the display
beyond certain values since they have no relation to reality.

 As long as this thread had been going for I'm surprised not recalling anyone ever validating the basic accuracy of the capacitance, resistance, ESR and Beta measurement results compared to other test equipment. Anyone recall testing and quantifying the accuracy?

Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on February 05, 2016, 06:09:40 am
I contend that any ESR reading of a capacitor below 1uF with these devices is bogus.
Again, I measured a .33uf capacitor with a 51 ohm resistor.  It read 2.2 ohms without
the resistor and 14 ohms with the resistor.  On another machine it read 1 ohm and 53
ohms respectivly as it should.  I invite everyone to make similar tests with a variety
of capacitor values.  I suggest these programs surpress ESR readings on the display
beyond certain values since they have no relation to reality.

A quick testing with 2 of the cheap testers (both M12864 - http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)) and an Agilent U1733C (@10kHz). The first column of values is from a M12864 with K firmware v1.12k r555. The second column of values is M12864 with M firmware v1.20m-trendy. Third column of values is the Agilent U1733C at 10kHz test frequency. Values are close enough for me.

                             M12864-K     M12864-M     U1733C
1uF Eloctro            3.6ohm        3.61ohm        3.813ohm
0.47uF Electro       4.1ohm        3.91ohm        4.218ohm
0.47uF Electro       3.8ohm        4.09ohm        4.068ohm
0.33uF Tantalum   3.5ohm        2.68ohm        3.522ohm
0.10uF Tantalum   9.7ohm        NoEsr            10.236ohm
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on February 05, 2016, 06:27:58 am
From the K firmware manual (ttester.pdf, pg42).

"You should not expect very good accuracy of measurement results, especially the ESR measurement and the results of inductance measurement are not very exact."

There is also a lot of other good information in the manual for how the testers actually test the ESR (as well as all other measurements) and what to expect.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on February 05, 2016, 06:40:28 am
I suggest these programs surpress ESR readings on the display beyond certain values since they have no relation to reality.

I'm pretty sure madires or someone else confirmed this many pages back in this thread. Quick search didn't find it, but really remember this being discussed.

Edit: Also supposed to suppress the ESR reading if the measured value is lower than internal resistance of the pins.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on February 05, 2016, 08:37:36 am
I suggest these programs surpress ESR readings on the display beyond certain values since they have no relation to reality.

I'm pretty sure madires or someone else confirmed this many pages back in this thread. Quick search didn't find it, but really remember this being discussed.

Edit: Also supposed to suppress the ESR reading if the measured value is lower than internal resistance of the pins.
Just for the laymen still unable to process that amazing project:

Why is  limited?
How would get improved? Would make it substantially more expensive?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 05, 2016, 01:06:46 pm

A quick testing with 2 of the cheap testers (both M12864 - http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)) and an Agilent U1733C (@10kHz). The first column of values is from a M12864 with K firmware v1.12k r555. The second column of values is M12864 with M firmware v1.20m-trendy. Third column of values is the Agilent U1733C at 10kHz test frequency. Values are close enough for me.

                             M12864-K     M12864-M     U1733C
1uF Eloctro            3.6ohm        3.61ohm        3.813ohm
0.47uF Electro       4.1ohm        3.91ohm        4.218ohm
0.47uF Electro       3.8ohm        4.09ohm        4.068ohm
0.33uF Tantalum   3.5ohm        2.68ohm        3.522ohm
0.10uF Tantalum   9.7ohm        NoEsr            10.236ohm

Wow thank you so much.
The result is quite impressive for a 17Euro circuit and surely good enough for my needs.
Again, kudos to the developers  :clap: :clap:
Anyway as always with all the test measurement tools, a bit of judgement on the measured values is needed depending on the specific component/situation/implementation of the measure...   

In this days I made some tests enabling the UART on the K-firmware and it works really well.
I was thinking to write a small Processing sketch to display the measurement on a big PC panel :)

I also need to test this supercap https://www.maxwell.com/images/documents/bcseries_ds_1017105-4.pdf (https://www.maxwell.com/images/documents/bcseries_ds_1017105-4.pdf)  (see page 3) and I will read the K-firmware documentation to verify if this can be achieved. Was this already discussed??

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2016, 01:49:40 pm
I also need to test this supercap https://www.maxwell.com/images/documents/bcseries_ds_1017105-4.pdf (https://www.maxwell.com/images/documents/bcseries_ds_1017105-4.pdf)  (see page 3) and I will read the K-firmware documentation to verify if this can be achieved. Was this already discussed??

The theoretical limit for capacitance is 100mF but I'd say the working limit is about 20mF. Goldcaps can't be measured at all (mostly detected as a diode or two anti-parallel diodes).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2016, 02:20:06 pm
I suggest these programs surpress ESR readings on the display beyond certain values since they have no relation to reality.

I'm pretty sure madires or someone else confirmed this many pages back in this thread. Quick search didn't find it, but really remember this being discussed.

Edit: Also supposed to suppress the ESR reading if the measured value is lower than internal resistance of the pins.

The m-firmware measures the ESR only for caps >180nF and any problem with the measurement will suppress the display of the ESR value. IIRC there is also a lower capacitance limit for the k-firmware. And it uses two different timings which improves the ESR measurement for small capacitances.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Seekonk on February 05, 2016, 02:42:48 pm
Just for reference for anyone else, this version isn't very good.  http://www.ebay.com/itm/271972464770?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/271972464770?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 05, 2016, 03:37:43 pm
I also need to test this supercap https://www.maxwell.com/images/documents/bcseries_ds_1017105-4.pdf (https://www.maxwell.com/images/documents/bcseries_ds_1017105-4.pdf)  (see page 3) and I will read the K-firmware documentation to verify if this can be achieved. Was this already discussed??

The theoretical limit for capacitance is 100mF but I'd say the working limit is about 20mF. Goldcaps can't be measured at all (mostly detected as a diode or two anti-parallel diodes).

Not studied yet the issue, but since this could be handy for a project, I was thinking to make a specific firmware function.
At page 3 of the datasheet i linked, there is the method to measure C and ESR of this beasts.
Is this a similar method implemented in the m and k firmware? (I'll read the documentation....)

The only limitation I can see is the time it will take the test, but this is not an issue for my needs.
Is there something else that will require a hardware change?

Thanks
     Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on February 05, 2016, 05:46:57 pm
Just for reference for anyone else, this version isn't very good.  http://www.ebay.com/itm/271972464770?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/271972464770?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

Actually it's not bad with updated f/w. It's known in this thread as the LCR-T4, check from post #939 approx. It's very cheap and easy to mount (Display quite close to the PCB). It does benefit from some more supply decoupling caps and maybe a change of reference IC (although the TL431 on board is ok). It's not a good choice if you want to start adding encoders for additional functions however.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on February 08, 2016, 03:34:46 pm
@Gyro, I have this exact tester which I payed $11 for it on AliExpress.  I am curious why do you say "It's not a good choice if you want to start adding encoders"?  I have one of this rotary encoders on order and I am planning to install it.  Once I get all the parts I am also planning to replace the 9V battery with a rechargeable Li-Ion and add a protection relay.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 08, 2016, 04:04:39 pm
The only limitation I can see is the time it will take the test, but this is not an issue for my needs.
Is there something else that will require a hardware change?

Just the 30 odd Ampere test current :) The tester can deliver 7mA (safely).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on February 08, 2016, 04:18:37 pm
@Gyro, I have this exact tester which I payed $11 for it on AliExpress.  I am curious why do you say "It's not a good choice if you want to start adding encoders"?  I have one of this rotary encoders on order and I am planning to install it.  Once I get all the parts I am also planning to replace the 9V battery with a rechargeable Li-Ion and add a protection relay.

Nothing specific, only that it is smd rather than through-hole like some of the others and very compact. There seem to be other ebay boards available now that include encoders, frequency inputs / outputs, voltage measurement etc. Some boards have Li-Ion psu built in too.

As my post hopefully conveyed, I like this board, I use it myself (together with a protection relay), but I have no need to extend it to additional functions or alternate power sources so haven't explored ease of expansion further than the relay. It's a good basic, accurate board and also cheap to replace if needed. I have no idea what Seekonk's issue with it was.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nowlan on February 09, 2016, 01:57:15 am
Not sure if this one is related, but looks to be junk.
https://www.youtube.com/watch?v=dD7kwy7FBwg (https://www.youtube.com/watch?v=dD7kwy7FBwg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 09, 2016, 08:09:17 am
He doesn't tear it apaaat, so I can't tell if it's AVR based, but it's likely unrelated. It only does L, C, and ESR.

However, at 9:00, the guy pulls out a Frejek AVR-Transistortester clone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Seekonk on February 09, 2016, 08:44:29 am
I have no idea what Seekonk's issue with it was.

My board was indeed a T4 version.  First cap I tested was 130pf.  It was really close, but I knew the 18 ohm ESR had no relation to anything.  I just wondered when it would start reading correctly.   People just tend to believe anything that is digital.  I have issues when they display a parameter that they know is inaccurate or has more digits than can be justified.  As a stock meter it appears you can do a lot better for just a little more money.  It looks like more effort is going into the encoder versions if you want to update the purchase.

It takes far too much effort to slog through this thread.   The unmodified performance of the various versions was buried a long time ago. Seems like that a performance comparison would a good separate thread to make a sticky out of.  I went for cost since I just needed inductance measurements at my camp.  It looks like a lot of effort has gone into modifying these.  Just suggesting people do a reality check with their standard versions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 09, 2016, 10:01:16 pm

Tutorial "How to use the Arduino as ISP Programmer (In-System Programmer)":
https://www.arduino.cc/en/Tutorial/ArduinoISP (https://www.arduino.cc/en/Tutorial/ArduinoISP)

The attached picture documenting my Arduino Duemilanove associated with the ATmega ISP Adapter (http://www.ebay.com/itm/ATmega8-ATmega48-ATMEGA88-Development-Board-AVR-NO-Chip-DIY-Kit-/281685097325).

I used official ArduinoISP sketch and this following commands:

For writing only Flash
avrdude -c avrisp -p m328p -P COM3 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a

For writing only Fuses (L=F7, H=D9, E=04)
avrdude -c avrisp -p m328p -P COM3 -b 19200 -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

For writing Flash + Fuses (L=F7, H=D9, E=04)
avrdude -c avrisp -p m328p -P COM3 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

Note:
For proper operation it is important to use a baud rate of 19200 and set the correct number of the communication port for Arduino.

Tom, correct me if I'm wrong, but I think you have a mistake here. I believe when using the ArduinoISP sketch to do your programming, you should use "-c arduino" parameter for AVRDUDE. The "avrisp" should be used for the official Arduino brand programmers (https://www.arduino.cc/en/Main/ArduinoISP). Maybe by chance, this method works anyway. I don't know.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 09, 2016, 10:12:51 pm
@ Seekonk
The most important hardware to look for (in terms of accuracy) are precision regulators or voltage references, and precision resistors (0.1%) on the test points. To my knowledge, no Chinese clones have regulators/references with sub 1% precision. But it's easy enough to upgrade yourself. It seems the firmware is more important, and can be easily updated on any model. The other things (graphical display, rotary encoder, ZIF socket) are sort of luxuries, and it's up to the user if they feel it's worth it. In my opinion, they are, and cost very little.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 10, 2016, 04:30:22 am
For writing only Fuses (L=F7, H=D9, E=04)
avrdude -c avrisp -p m328p -P COM3 -b 19200 -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

Pardon me if I'm mistaken, but I think the efuse value you give is incorrect.
According to the Atmel datasheet (Table 29-12), 4.3V Brown Out Detection is:
BOD Level 2 = unprogrammed, BOD Level 1 = programmed, BOD Level 0 = programmed, or 100
Therefore, the entire extended fuse byte would be 1111 1100 or 0xFC

EDIT: I just tested it myself and even though it doesn't follow the datasheet, the MCU doesn't seem to care if the first 5 bits are 0s or 1s. In other words, 1111 1100 and 0000 0100 do the same thing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 10, 2016, 08:38:45 am
Everything is fine. Because some numerical values refer to fuses containing undefined bits. Value FC set this bits to '1' and value 04 set this undefined bits to '0'. Depending on the target device these fuse bits will be read either as '0' or '1' (may result in the verification error).
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 10, 2016, 09:25:40 am
Tom, correct me if I'm wrong, but I think you have a mistake here. I believe when using the ArduinoISP sketch to do your programming, you should use "-c arduino" parameter for AVRDUDE. The "avrisp" should be used for the official Arduino brand programmers (https://www.arduino.cc/en/Main/ArduinoISP).

Everything should be okay because Arduino as ISP is very similar to the STK500 1.x.
Title: Re: $20 LCR ESR Transistor checker project
Post by: speedy29 on February 10, 2016, 08:29:10 pm
@tom666
Programmer arrived, processor successfully written with avrdude program.
With extreme burn program, I had problems in the schivere Fuse.

Thank you...  :-+

P.S. I should also repair a FISH8840, you put the backup without merged, those are standard for 328P?   ::)
And 'possible to obtain the complete string to perform a backup with avrdude?
Grazie
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 10, 2016, 10:01:02 pm
@speedy29

Attached zip file contains the original firmware for Fish8840. It is of course possible to use the k-version software from the SVN repository (directory mega328_fish8840).

Fuse settings fot M328P:
lfuse:0xf7 hfuse:0xd9 efuse:0x04 (0xfc)

To backup the firmware, you can use the following command:
Code: [Select]
avrdude -c usbasp -p m328p -B 0.5 -U flash:r:"TransistorTester.hex":i -U eeprom:r:"TransistorTester.eep":iHowever, if the contents of the MCU is locked, so you're out of luck.
Title: Re: $20 LCR ESR Transistor checker project
Post by: speedy29 on February 11, 2016, 05:04:37 pm
Thank you.
Up I had already downloaded from your old 3d, and I asked you about merged, thanks.
As for ilo backup, they are aware of the possibility to read lock.
Thank you. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 12, 2016, 02:28:38 pm
The only limitation I can see is the time it will take the test, but this is not an issue for my needs.
Is there something else that will require a hardware change?

Just the 30 odd Ampere test current :) The tester can deliver 7mA (safely).

I think I need to better detail my initial intention...
We don't need to push 30A on the capacitor to measure C and ESR
It will be fine to use 2 or 3 amps to perform the measure safely in few minutes.
I made some tests with a constant current PSU (set at 2V and 2A) and an oscilloscope, and for the purpose of my project I can verify my 350F Ultracaps easily and precisely.

Just to prove the concept of using my M12864 to automate the measure, the idea was to just have a specific firmware function to control a constant current source ,a dummy load (for the discharge) and read the values of C and ESR with the M12864.
Of course I will need to add external hardware to provide the extra current/sink, and modify the firmware to extend the measure time, but theoretically should work.

In this days I made the last mod on the case, adding a slot for the ICSP and another to easily connect to the UART, to the Frequency counter and to the PWM/square wave output (see picture)  :).

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: speedy29 on February 13, 2016, 07:28:25 am
@ tom666
question, but the backups you've attached it to the device with graphic display, like the one I am attaching?
Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 13, 2016, 09:16:52 am
@speedy29
Yes, it's backup firmware from Fish8840 tester with the graphic display (http://lygte-info.dk/review/ComponentTester%20Fish8840%20UK.html).
Title: Re: $20 LCR ESR Transistor checker project
Post by: speedy29 on February 13, 2016, 09:26:32 am
Tom, as they say in Italian, "if you're not, have to invent".   :-+

Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 13, 2016, 10:35:58 am
Sorry, I don't understand this Italian proverb :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 13, 2016, 06:22:35 pm
Perhaps it's the equivalent of the old saying, "Necessity is the mother of invention."
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on February 13, 2016, 06:27:01 pm
Or more likely...'If you didn't exist, it would be necessary to invent you!' (it's a compliment  :) )
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 13, 2016, 06:37:15 pm
Ah, I can see that now. It's a great compliment indeed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: speedy29 on February 13, 2016, 09:31:09 pm
Or more likely...'If you didn't exist, it would be necessary to invent you!' (it's a compliment  :) )
  :-+
Yes,  It's a great compliment indeed.
Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: avrank on February 16, 2016, 08:55:52 am
Please help me,
I use a yellow board t3 t4, and compile file M, but the display is still not perfect as in the picture. What's wrong ? Thankyou.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on February 16, 2016, 12:51:34 pm
I have an older EZM Electronic Studio version bought from eBay a couple of years ago (see picture below).  It uses a Mega328 DIP IC, seems not to have a ICSP connector, and after calibration, reports software vn1.07k

I'm looking at doing any upgrades that may be worthwhile but should I just go buy one of the newer ones for $20?

I believe I can upgrade the firmware but which version is recommended and what improvements does it have?
With no ICSP, do I take the Mega328 out of its socket and program like that?
What components are worth upgrading?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on February 16, 2016, 01:49:09 pm
What components are worth upgrading?
0.1% Resistors onboard but no precision voltage ref, perhaps you may add one.
If there is enough space you can switch the tactile for an encoder.
If you like to test small capacities and/or inductives with actual K-Firmware you need to change the crystal for 16MHz too.
Please refer to the actual ducuments on github/mikrocontroller.net.


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 16, 2016, 02:34:24 pm
Please help me,
I use a yellow board t3 t4, and compile file M, but the display is still not perfect as in the picture. What's wrong ? Thankyou.

I can read "PWM" and "ESR". The other lines seem to be the same gibberish. That could mean that the items got the same broken pointer. When you enter the PWM tool, do you get a nice list of the frequencies or more gibberish?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 16, 2016, 06:18:02 pm
Hi,frends! Karl-Heinz Kübbeler and Pieter-Tjerk de Boer added possibility of check and testing of crystal and ceramic resonators in new revision(actual 638th) of an insertion! I tested all resonators which I have and was very pleased with this new function.Definition of resonators with a frequency from 1 MHz to 13 MHz is possible!
But for its work it is necessary to establish in tester hardware crystal with a frequency of 16 MHz. It is obligatory! And also it is necessary to add in the makefile the line CFLAGS + = - DWITH_XTAL and change line OP_MHZ = 16
Title: Re: $20 LCR ESR Transistor checker project
Post by: avrank on February 17, 2016, 03:25:34 am
Please help me,
I use a yellow board t3 t4, and compile file M, but the display is still not perfect as in the picture. What's wrong ? Thankyou.

I can read "PWM" and "ESR". The other lines seem to be the same gibberish. That could mean that the items got the same broken pointer. When you enter the PWM tool, do you get a nice list of the frequencies or more gibberish?

When enter the PWM, text display is good, as shown below mr...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2016, 02:03:34 pm
I can read "PWM" and "ESR". The other lines seem to be the same gibberish. That could mean that the items got the same broken pointer. When you enter the PWM tool, do you get a nice list of the frequencies or more gibberish?

When enter the PWM, text display is good, as shown below mr...

Could be some garbage in the EEPROM. I'd try to re-flash the firmware and the eeprom.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlxDroidDev on February 18, 2016, 01:14:13 pm
After a 62 days wait for delivery, I finally got mine last night. It is a M12864, exactly like this one:

(http://img.banggood.com/images/2014/xiemeijuan/09/SKU263599SKU273392/SKU263599-4.jpg)

It uses an 8Mhz crystal and all resistors are 1%.
It was assembled and tested and works great! I also dumped the firmware (v1.17) and EEPROM that came with it so I have a copy and can safely play with updates.

Now my questions:
- is my board compatible with the latest firmware (641) on svn? Are there any modifications required?
- if not, what is the latest firmware I can install on my board?

Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 18, 2016, 04:02:48 pm
@AlxDroidDev

It was here several times already mentioned.

Your tester is an identical copy of the original concept and is therefore compatible with the k-version (Karl-Heinz Kübbeler aka kubi48) and m-version (Markus Reschke aka madires) of the software.

Your dump (v1.17 ???) is probably useless, because the contents of the MCU is standard locked. Basically it does not matter, because the author of this software is Karl-Heinz Kübbeler. Therefore, without any modifications you can be applied directly his original software (directory mega328_st7565_kit (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/?view=tar)).

However, I recommend carefully studied the official manual (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar) ;)

:phew:

Note:

... It uses an 8Mhz crystal and all resistors are 1%. ...

Interesting, because all kits of this tester, that went through my hands contained the precise (0.1%) value of the test resistors 680 and 470k.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlxDroidDev on February 18, 2016, 05:33:20 pm
Thank you, @Tom.

Do you think I should set the lock bits after flashing a new firmware ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 18, 2016, 05:41:38 pm
You need to set only the standart fuses:
Code: [Select]
lfuse:0xf7 hfuse:0xd9 efuse:0x04 (0xfc)
Title: Re: $20 LCR ESR Transistor checker project
Post by: avrank on February 19, 2016, 06:31:13 am
Please help me,
I use a yellow board t3 t4, and compile file M, but the display is still not perfect as in the picture. What's wrong ? Thankyou.

I can read "PWM" and "ESR". The other lines seem to be the same gibberish. That could mean that the items got the same broken pointer. When you enter the PWM tool, do you get a nice list of the frequencies or more gibberish?

When enter the PWM, text display is good, as shown below mr...

Thank you sir ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on February 19, 2016, 09:33:42 pm
I have an older EZM Electronic Studio version bought from eBay a couple of years ago

I have the exact same unit.  I've made a few modifications:
I try to keep mine up to date with the latest M-firmware.

I used to remove the processor to program it, but then I made a cable for my USBASP programmer, using IC test clips (http://www.ebay.com/itm/10pcs-New-5-Color-Mini-Grabber-SMD-IC-Test-Clip-Hook-Probe-Jumper-/261225257375). With the display removed, I clip them to R4, R5, R6 and R7 for the signals, and on C6 for power.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 20, 2016, 06:30:17 am
Markus,

I have the ST7565 kit tester. The rotary encoder is connected to PD1 and PD3. How do I configure this in your software please?

Also, did you write code to support the extra ADC pins of the m328 QFP package? And if not, do you plan to?

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on February 20, 2016, 08:34:49 am
I thinking about this:

http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/181998165302?hash=item2a5fef9d36:g:z2gAAOSw5dNWoH5f (http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/181998165302?hash=item2a5fef9d36:g:z2gAAOSw5dNWoH5f)

Is the rotary encoder a good solution?It requires custom firmware for an upgrade?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 20, 2016, 12:58:22 pm
@caius

A rotary encoder is used for easier menu navigation and control functions of the tester. For this DIY KIT of the tester can be used directly to original k-version software without any modifications - either way, this Chinese clone contains exactly this firmware (v1.12k) ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on February 20, 2016, 01:09:14 pm
@caius

A rotary encoder is used for easier menu navigation and control functions of the tester. For this DIY KIT of the tester can be used directly to original k-version software without any modifications - either way, this Chinese clone contains exactly this firmware (v1.12k) ;)

OK, thanks for explanation.Is v1.12K the latest and best firmware available?Which are issues(I know there are)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 20, 2016, 01:31:30 pm
@caius

Currently is it the most appropriate version of software. K-version is under development and testing, but so far everything is working normally. If you know of any bugs, please give some information. I recommend carefully studied the official manual!
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on February 20, 2016, 01:34:55 pm
@caius

Currently is it the most appropriate version of software. K-version is under development and testing, but so far everything is working normally. If you know of any bugs, please give some information. I recommend carefully studied the official manual!

OK, I'll get the kit and test the assembled unit reporting feedback.Thanks for you help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 20, 2016, 01:40:41 pm
@caius
Off topic:
Please, do not use unnecessarily the button quote :)
Just use only the reply ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on February 20, 2016, 01:43:44 pm
I was going to use the reply button but then I thought someone would not have understood mine was a reply to your post  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 20, 2016, 02:18:18 pm
@caius
OT: If the question or reply is immediately after the post msg, it is not unnecessary to use the quote. Some users have also problem with this :(

Note:
Button "Quote" should not be used to the last post - but it would have to set the administrator of this discussion forum.
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on February 20, 2016, 02:22:19 pm
OK, roger  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 20, 2016, 02:35:49 pm
I have the ST7565 kit tester. The rotary encoder is connected to PD1 and PD3. How do I configure this in your software please?

Everything is in config.h ;) Enable the rotary encoder option (#define HW_ENCODER), set pulses/detents (#define ENCODER_PULSES   2) and adjust the encoder I/O pins (#define ENCODER_A   PD1). And there's a dedicated section for the M12864's display.

Quote
Also, did you write code to support the extra ADC pins of the m328 QFP package? And if not, do you plan to?

Not yet, but if an interesting hardware option for one of the extra pins comes up ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on February 20, 2016, 02:37:02 pm
LCR-TC now in color, and shall probably sell for 50usd on ebay.  Not an owner yet, I can't show more.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 20, 2016, 02:41:55 pm
OK, roger  :)

Sorry. I did not intend to touch you somehow :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on February 20, 2016, 02:50:10 pm
No, you are perfectly right!We have to respect the netiquette all the time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 20, 2016, 02:54:16 pm
LCR-TC now in color, and shall probably sell for 50usd on ebay.  Not an owner yet, I can't show more.

That modified firmware has nice graphics. Unfortunately the author doesn't provide the source code and ignores that the firmware is open source. :-- But we have color support too. And I think I'm able to add touch screen support for an ATmega 664/1284 version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlxDroidDev on February 20, 2016, 06:18:14 pm
I got mine working with Trendy 1.21m!

I want to thank Markus for the superb job he`s done with the firmware, and specially thank him for supporting all the hardware that others have developed around his initial project. He's done such a great work, I don't even care about losing 7x1 to Germany!

I also want to thank tom666 for the huge amount of help he`s been giving everyone and the time and effort he's put into this forum.

Guys, you are awesome!
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 20, 2016, 08:36:18 pm
Not yet, but if an interesting hardware option for one of the extra pins comes up ...

 :-BROKE

Oscilloscope input of course.  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 20, 2016, 08:48:20 pm
Sorry. I did not intend to touch you somehow :)

Tom, this is a poor choice of the word "touch". We understand what you mean, but in another situation, it might sound criminal.

Use instead: I did not intent to piss you off/irritate you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 20, 2016, 09:50:39 pm
I want to thank Markus for the superb job he`s done with the firmware, and specially thank him for supporting all the hardware that others have developed around his initial project. He's done such a great work, I don't even care about losing 7x1 to Germany!

Actually, there are two Markus'. Markus F. is the original author but abandoned the project. I'm Markus R. and writing the m-firmware. And there's also Karl-Heinz who does the k-firmware and leads the project. It's a lot of fun and I'm happy (I bet Karl-Heinz too) that people like what we've achieved so far.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 21, 2016, 05:11:30 am
Everything is in config.h ;)

I was looking for the pin options under the "Hardware options" section where you enable the R.E. and set pulses. Now I see it under the "port and pin assignments" section. Thank you.

I'm having a problem with some random pixels now. They don't appear with the 'K' FW.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 21, 2016, 02:15:48 pm
I'm having a problem with some random pixels now. They don't appear with the 'K' FW.

Looks like to be the 4 pixel offset. Please enable "#define LCD_OFFSET_X" in the display section and try again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 21, 2016, 08:46:54 pm
The offset is turned on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: biohazrd on February 21, 2016, 09:14:01 pm
Is anyone aware if this (http://smile.amazon.com/OSOYOO-Mega328-Transistor-Tester-Capacitance/dp/B015WAYINM/ref=pd_cp_147_4?ie=UTF8&refRID=0MMDYXRMQ89Q3F3P17JJ) is a compatible version? I'd like to pick one up and check the resistor tolerance (although I'm not the best SMD solderer)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 21, 2016, 09:15:37 pm
You actually need to comment that line to remove the offset as madires already point it to me.
In my previous post (https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg858999/#msg858999)
You can find the following list of all changes you need to make on the config.h to have the m-firmware working correctly with M12684 DYI Kit


Config.h Changes to work with M12684 DIY KIT (Banggood)

Section:
/*
 *  M12864 DIY Transistor Tester
 *  - ST7585 display
 *  - rotary encoder at PD1/3
 */
Uncomment entire secion and comment other LCD sections

Change to
//#define LCD_OFFSET_X
#define LCD_CONTRAST     5 


Section:
/* **********************************
 *   Hardware options
 * ********************************** */
Uncomment
#define HW_ENCODER
#define HW_REF25

This should be already
#define UREF_25           2495 //Tipical output of TL431AA (you shuld measure it?)


Section:
/* **********************************
 *   port and pin assignments
 * ********************************** */
Change to
#define ENCODER_A        PD1       /* rotary encoder A signal */

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 21, 2016, 11:11:10 pm
In this days I played a bit with the UART output on my M12864 DIY Kit with k-firmware.
The idea is to log on a PC all the measurement and visualize the results on a big Processing display (see attachment).
To simplify the Processing sketch, I added a "new_line" = ("\r\n") at the end of each line of text sent to the UART.
In this way the text on the serial output is much more readable also on a serial terminal and helps me a lot to identify the position of the text and visualize it correctly.
This is the list of all changes I made so far.
Hope this is helpful for someone.

main.c
…………..
    #ifdef WITH_UART
       //uart_putc(' ');      // start of next value                      //MAURO Removed
       uart_newline();                                            //MAURO Added
    #endif
…………..
    #ifdef WITH_UART
       //uart_putc(0x03);   // ETX, start of new measurement  //Mauro Removed
       uart_newline();                                       //MAURO Added
    #endif

**********************
lcd-routines.c
Replaced every uart_putc(' '); with uart_newline();    //MAURO Added

In the "switch(temp1) {" inside the lcd-routines.c the following line were missing causing a corruption in the UART output.
I think this is the biggest bug I can find in this amazing firmware  :)

    case LCD_CHAR_INDUCTOR1:
    case LCD_CHAR_INDUCTOR2:
       uart_putc('L');
       break;

At the moment I don't know where I need to add the uart_newline();  to wrap the text of the Selection menu  :-//
Now it looks like this:

Selection:
 Switch off     >Transistor      Frequency       Transistor     >Frequency       f-Generator     Frequency      >f-Generator     10-bit PWM      f-Generator    >10-bit PWM      C+ESR@TP1:3     10-bit PWM     >C+ESR@TP1:3     1-RR-LL-3       C+ESR@TP1:3    >1-RR-LL-3       1-||-3           1-RR-LL-3      >1-||-3           C(uF)-correction 1-||-3          >C(uF)-correction Selftest        C(uF)-correction>Selftest        Contrast        C(uF)-correction>Selftest        Contrast        C(uF)-correction>Selftest        Contrast        C(uF)-correction>Selftest        Contrast

And I would like to have it like this:

Selection:
Switch off     
>Transistor     
Frequency       

Transistor     
>Frequency       
f-Generator     

Help Help  :scared:

In the mean time I made the last modification to the case  :-DMM

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on February 22, 2016, 02:15:21 am
LCR-TC now in color, and shall probably sell for 50usd on ebay.  Not an owner yet, I can't show more.

That modified firmware has nice graphics. Unfortunately the author doesn't provide the source code and ignores that the firmware is open source. :-- But we have color support too. And I think I'm able to add touch screen support for an ATmega 664/1284 version.

Soon it shall be LCR-TTC or LCR-TCT :-)  I am glad, I did not get every version that came out. 

My first tester is from a French company, MW Instruments, now defunct.  The unit is able to do opto-coupler testing.  And for the unit to know the "opto-coupler" testing mode, an adapter board need to be attached before powering on.  The various parameters of the coupler are displayed after testing, including the CTR.  Is this a possibility for the your software? 

The layout for the adapter board is attached.  The adapter board is connected by the 3 testing leads to MW tester, and in specific order.

Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 22, 2016, 05:22:01 am
@Mauroh
Thank you very much for that. Disabling the offset fixed the problem.

Uncomment
#define HW_REF25

Since this kit came with 3% regulator, and only 1% reference, this option probably won't make a significant difference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 22, 2016, 05:38:45 am
I discovered some strange things ....

I was checking my fuses:

Code: [Select]
avrdude -c arduino -p m328p -P /dev/tty.usbserial -b 19200 -U lfuse:r:-:h -U hfuse:r:-:h -U efuse:r:-:h -U lock:r:-:h

avrdude: Device signature = 0x1e950f
avrdude: reading lfuse memory:
0xf7
avrdude: reading hfuse memory:
0xd9
avrdude: reading efuse memory:
0x4
avrdude: reading lock memory:
0x3f

avrdude: safemode: Fuses OK (H:04, E:D9, L:F7)

That last line worries me because it contradicts the read fuse values. Is that a bug in AVRDUDE?

Writing the lock byte fails:

Code: [Select]
avrdude -P /dev/tty.usbserial -c arduino -p m328p  -b 19200 -B 20 -U lock:w:0xff:m

avrdude: reading input file "0xff"
avrdude: writing lock (1 bytes):

Writing |                                                    | 0% 0.00s ***failed; 
Writing | ################################################## | 100% 0.16s

avrdude: 1 bytes of lock written
avrdude: verifying lock memory against 0xff:
avrdude: load data lock data from input file 0xff:
avrdude: input file 0xff contains 1 bytes
avrdude: reading on-chip lock data:

Reading | ################################################## | 100% 0.02s

avrdude: verifying ...
avrdude: verification error, first mismatch at byte 0x0000
         0x3f != 0xff
avrdude: verification error; content mismatch

And setting the efuse fails too:

Code: [Select]
avrdude -P /dev/tty.usbserial -c arduino -p m328p -b 19200 -B 20 -U efuse:w:0xFC:m
avrdude: reading input file "0xfc"
avrdude: writing efuse (1 bytes):

Writing |                                                    | 0% 0.00s ***failed; 
Writing | ################################################## | 100% 0.16s

avrdude: 1 bytes of efuse written
avrdude: verifying efuse memory against 0xfc:
avrdude: load data efuse data from input file 0xfc:
avrdude: input file 0xfc contains 1 bytes
avrdude: reading on-chip efuse data:

Reading | ################################################## | 100% 0.02s

avrdude: verifying ...
avrdude: verification error, first mismatch at byte 0x0000
         0x04 != 0xfc
avrdude: verification error; content mismatch

I tried different bit clocks and it doesn't make a difference. Am I missing something?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on February 22, 2016, 08:53:48 am
Writing the lock byte fails and setting the efuse fails too.

It's a problem of undefined bits. For example, the value FC for efuse set this bits to '1' and value 04 set this undefined bits to '0'. Depending on the target device these fuse bits will be read either as '0' or '1'. Therefore, it may cause errors in verification. This same applies to the lock bits, because the upper two bits in the byte are unused.

Note:
I have not noticed the other problems - I recommend updating the program AVRDUDE (http://download.savannah.gnu.org/releases/avrdude/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 22, 2016, 12:50:31 pm
Since this kit came with 3% regulator, and only 1% reference, this option probably won't make a significant difference.

The voltage reference is a TL431A that should be 2% and the critical resistors at the inputs are 0.1% not 1% as all the others on the board.
It will not change the world but it is better  :)

The unit is able to do opto-coupler testing.  And for the unit to know the "opto-coupler" testing mode, an adapter board need to be attached before powering on.  The various parameters of the coupler are displayed after testing, including the CTR.  Is this a possibility for the your software? 

See attached the picture with my version of the opto-coupler adapter  :)
Yes, it is really ugly but worked with all the opto-coupler I tested so far (4 and 6 pins), not tried with optotriacs.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlxDroidDev on February 22, 2016, 01:19:32 pm
Quote
Writing the lock byte fails and setting the efuse fails too.

It's a problem of undefined bits. For example, the value FC for efuse set this bits to '1' and value 04 set this undefined bits to '0'. Depending on the target device these fuse bits will be read either as '0' or '1'. Therefore, it may cause errors in verification. This same applies to the lock bits, because the upper two bits in the byte are unused.

Note:
I have not noticed the other problems - I recommend updating the program AVRDUDE (http://download.savannah.gnu.org/releases/avrdude/).

Actually, I had the same problem, but only when using the latest version of avrdude.exe and avrdude.conf, both downloaded from the site above.

When using the version of avrdude (.exe and .conf ) that comes with Arduino 1.6.7, I have absolutely no problems, including setting efuse.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 22, 2016, 05:51:50 pm
My first tester is from a French company, MW Instruments, now defunct.  The unit is able to do opto-coupler testing.  And for the unit to know the "opto-coupler" testing mode, an adapter board need to be attached before powering on.  The various parameters of the coupler are displayed after testing, including the CTR.  Is this a possibility for the your software? 

Could be. I have to check if it's feasable.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 23, 2016, 08:33:05 am
Writing the lock byte fails and setting the efuse fails too.
It's a problem of undefined bits....
I think it might have to do with the device. When I was flashing a QFP m328p, it didn't care if the upper bits were 0 or 1. This problem started when I tried flashing a DIP package.
It seems logical to me that high bits should be left as '1' since, in Atmel's own words, bits "can be left unprogrammed (“1”) or can be programmed (“0”) to obtain the additional features". Even online fuse calculators (here (http://eleccelerator.com/fusecalc/fusecalc.php?chip=atmega328p), here (http://www.engbedded.com/fusecalc/)) display the undefined bits as '1'. Oh well.


I recommend updating the program AVRDUDE.
I had the same problem, but only when using the latest version of avrdude.exe ... When using the version of avrdude (.exe and .conf ) that comes with Arduino 1.6.7, I have absolutely no problems...
I am using AVRDUDE 6.0.1, because that's what came with CrossPack (toolchain for Mac OS). The AVRDUDE that is packaged with my Arduino IDE (1.6.1) is also 6.0.1.  The latest version is 6.3.

I'll do some more testing with the undefined bits, and try to find some different AVRDUDE binaries (but I'm not keen on downgrading).


The voltage reference is a TL431A that should be 2% and the critical resistors at the inputs are 0.1% not 1% as all the others on the board. It will not change the world but it is better  :)
My kit came with a "Wing Shing" brand 431 reference. (datasheet (http://data.datasheetlib.com/pdf1/140/48/1404808/wing-shing-computer-components-tl431a_553243decf.pdf)). Grade A = 1% (allegedly, page 3). Its precision is in the same order of magnitude as the regulator. As has been discussed in this topic (and like the config.h comment says), there's no significant improvement from enabling #define HW_REF25, unless the reference is 10x more precise. I plan to order some MCP1702's, so the 431 will be useless anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 23, 2016, 09:05:38 am
Code: [Select]
avrdude -c arduino -p m328p -P /dev/tty.usbserial -b 19200 -U lfuse:r:-:h -U hfuse:r:-:h -U efuse:r:-:h -U lock:r:-:h

avrdude: Device signature = 0x1e950f
avrdude: reading lfuse memory:
0xf7
avrdude: reading hfuse memory:
0xd9
avrdude: reading efuse memory:
0x4
avrdude: reading lock memory:
0x3f

avrdude: safemode: Fuses OK (H:04, E:D9, L:F7)

That last line worries me because it contradicts the read fuse values. Is that a bug in AVRDUDE?

Confirmed. Bug #45115. Fixed in avrdude 6.1
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 23, 2016, 09:06:56 am
My kit came with a "Wing Shing" brand 431 reference. Grade A = 1%

My typo on the 431, yes it is 1%

Quote
there's no significant improvement from enabling #define HW_REF25, unless the reference is 10x more precise.
I plan to order some MCP1702's, so the 431 will be useless anyway.

Agree

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 23, 2016, 02:23:19 pm
My first tester is from a French company, MW Instruments, now defunct.  The unit is able to do opto-coupler testing.  And for the unit to know the "opto-coupler" testing mode, an adapter board need to be attached before powering on.  The various parameters of the coupler are displayed after testing, including the CTR.  Is this a possibility for the your software? 

Could be. I have to check if it's feasable.

After reading a few datasheets of opto couplers I think the CTR could be measured with some caveats. The main problem is current. Considering the LED's voltage drop the tester could drive it with about 5mA using Rl (680 Ohms). But the collector curent will become a problem, since the tester can't provide more than 7mA in a safe way. Though, we could overload the MCU's pin briefly. So an external test adapter with an additional current limiting resistor for the LED (aiming for 1mA) could solve that issue. Or a second resistor for the collector, i.e. the MCU provides full current limited by its internal resistance and the additional resistor limits the maximum current to some acceptable value. Or maybe both to support also couplers with a darlington output stage. But the optimal LED current seems to be around 5-10mA. Either we'd have an optimal LED driver current and a CTR range of maybe up to 500% or a not so ideal drive current and a CTR range of up to 5000%. Any suggestions?
Title: Re: $20 LCR ESR Transistor checker project
Post by: iamdarkyoshi on February 23, 2016, 04:18:08 pm
I have a similar one but it uses a graphical LCD. It was a really nice unit. But now it does not work. Maybe a repair thread in the future
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 23, 2016, 10:25:35 pm
After reading a few datasheets of opto couplers I think the CTR could be measured with some caveats.

This is what I got testing few optocouplers with the actual firmware.

Motorola 4N33   CTR 500% Darlingron
BJT-NPN
hFE=10
Ie=5.2mA
Ube=1.03V     
Pin 1=B 2=E 3=C


Lite-On 817B   CTR 130-260%
BJT-NPN
hFE=1
Ie=3.9mA
Ube=1.09V
Pin 1=B 2=E 3=C


QTC 4N35   CTR 100%
BJT-NPN
hFE=0
Ic=0uA
Ube=807mV
Pin 1=B 2=E 3=C

Not bad for a PASS/FAIL test and the measured "hFE" gives a reasonable indication of the order of magnitude of the CTR.
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on February 24, 2016, 04:43:57 am
After reading a few datasheets of opto couplers I think the CTR could be measured with some caveats. The main problem is current. Considering the LED's voltage drop the tester could drive it with about 5mA using Rl (680 Ohms). But the collector curent will become a problem, since the tester can't provide more than 7mA in a safe way. Though, we could overload the MCU's pin briefly. So an external test adapter with an additional current limiting resistor for the LED (aiming for 1mA) could solve that issue. Or a second resistor for the collector, i.e. the MCU provides full current limited by its internal resistance and the additional resistor limits the maximum current to some acceptable value. Or maybe both to support also couplers with a darlington output stage. But the optimal LED current seems to be around 5-10mA. Either we'd have an optimal LED driver current and a CTR range of maybe up to 500% or a not so ideal drive current and a CTR range of up to 5000%. Any suggestions?

Maybe can tap out the VCC, and push some complexity to the adapter board?  So far, I am an armchair user for these testers, and got not much knowledge on the working.  Please be kind with me :-)

Two pages from the MW tester, one is the base circuit, and one of the opto-coupler test adapter.  I hope many more type of opto-coupler can be tested, as more and more are using those with built-in drivers.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 24, 2016, 01:21:16 pm
Not bad for a PASS/FAIL test and the measured "hFE" gives a reasonable indication of the order of magnitude of the CTR.

We can do better than that ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 24, 2016, 02:06:41 pm
Two pages from the MW tester, one is the base circuit, and one of the opto-coupler test adapter.  I hope many more type of opto-coupler can be tested, as more and more are using those with built-in drivers.

Thanks for the PDFs! At the moment I think that the approach with 5mA I_f and a brief pin overload for I_c is the best option. Maybe I find a solution to support also high CTRs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: speedy29 on February 24, 2016, 07:00:01 pm
@speedy29

Attached zip file contains the original firmware for Fish8840. It is of course possible to use the k-version software from the SVN repository (directory mega328_fish8840).

Fuse settings fot M328P:
lfuse:0xf7 hfuse:0xd9 efuse:0x04 (0xfc)


Fully functional.

 Thank you again
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 28, 2016, 12:12:56 am
Karl-Heinz made a new build of the k firmware (656) that support 2 decimal places for the hFE!!!
I tested some optocouplers with great and consistent results.

Thank you Karl-Heinz  :clap:

Toshiba P181 GB Datasheet CTR 100-600   (3 different devices)
BJT-NPN    hFE=2.71   Ie=4.4mA  Ube=1.07V
BJT-NPN    hFE=1.96   Ie=4.1mA  Ube=1.08V
BJT-NPN    hFE=2.12   Ie=4.2mA  Ube=1.08V

Sharp PC817A  Datasheet CTR 80-160  (2 different devices)
BJT-NPN    hFE=.64     Ie=3.4mA  Ube=1.11V
BJT-NPN    hFE=.84     Ie=3.6mA  Ube=1.10V

Liteon 816A Datasheet CTR 80-160   (2 different devices)
BJT-NPN    hFE=1.01   Ie=3.7mA  Ube=1.11V
BJT-NPN    hFE=.84     Ie=3.6mA  Ube=1.10V

Motorola 4N33 Datasheet CTR > 500    (2 different devices)   
BJT-NPN    hFE=6.00   Ie=4.9mA  Ube=1.05V
BJT-NPN    hFE=10.4   Ie=5.2mA  Ube=1.04V

QTC 4N35 Datasheet CTR 100         
BJT-NPN    hFE=.83     Ie=3.6mA  Ube=1.09V

Kento JC817 Datasheet CTR 50-600      
BJT-NPN    hFE=1.51   Ie=4.0mA  Ube=1.09V

Liteon 817B Datasheet CTR 50-600   (3 different devices)
BJT-NPN    hFE=1.23   Ie=3.8mA  Ube=1.10V
BJT-NPN    hFE=1.38   Ie=3.9mA  Ube=1.10V
BJT-NPN    hFE=1.28   Ie=3.9mA  Ube=1.09V

Sharp PC123E Datasheet CTR 50-600  (4 different devices)
BJT-NPN    hFE=.95    Ie=3.7mA  Ube=1.10V
BJT-NPN    hFE=.75    Ie=3.5mA  Ube=1.10V
BJT-NPN    hFE=.95    Ie=3.7mA  Ube=1.10V
BJT-NPN    hFE=.82    Ie=3.6mA  Ube=1.10V

MOC3041 OptoTriac               
BJT-NPN    hFE=326   Ic=2.8mA  Ube=821mV
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 28, 2016, 03:38:34 pm
Karl-Heinz made a new build of the k firmware (656) that support 2 decimal places for the hFE!!!
I tested some optocouplers with great and consistent results.

The results look promising. Have you cross-checked some CTRs by a manual measurement, i.e. lab PSU (5V), series resistor for the LED (around 5mA, 750 Ohms) and a DMM? The hFE measument for the common emitter circuit is done using the 470k resistor as base (opto coupler:LED) resistor. Those few µA are too low for driving the LED. So the hFE measurement for the common collector circuit (emitter follower) using the 680 Ohms base resistor delivers the value. But the emitter resistor is also a 680 Ohms one, which brings the LED's drive current down to about 2.8mA (LED's cathods and BJT's emitter are connected). Hmm, the datasheets of opto couplers depict common emitter test circuits. Just trying to figure out the best way to measure the CTR.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 01, 2016, 11:46:15 am
I'll try to make few tests an let you know.
For the moment I think it is great even though it under estimate the values of devices with large CTR.

I don't want change topic, but in this days I made several tests with supercapacitors (350F) and studied the documentation of the k-firmware:
As stated several times without external hardware we are out of luck to measure the capacitance of that beasts, but since the actual transistor tester identify the supercapacitors as a low resistance, the ESR measurement routine is used to get the measurement (that has a better resolution).
This means that for supercapacitors the actual transistor tester measure just the ESR (displaying -RR-LL-) without even considering to measure the capacitance.
This is great and already helped me out to test some leaking supercapacitors inside a complex electrical mechanical device (not easy to take apart and too much effort just to check the supercaps  :phew:)

Do you know which is the best way to report firmware bugs? I think i'll have to use my few German words  :scared:

Small bug:
In the "switch(temp1) {" inside the lcd-routines.c the following line were missing causing a corruption in the UART output.

    case LCD_CHAR_INDUCTOR1:
    case LCD_CHAR_INDUCTOR2:
       uart_putc('L');
       break;

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 01, 2016, 12:50:19 pm
Do you know which is the best way to report firmware bugs? I think i'll have to use my few German words  :scared:

I'll forward your bug report to Karl-Heinz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 01, 2016, 01:41:24 pm
Vielen dank  :-+
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2016, 03:26:27 pm
Some update on the opto coupler check for the m-firmware. It's going to be a tool in main menu because I think a dedicated measurement provides more accurate results. It also allows to tell a BJT or Triac type apart. And adding support for other types might be also possible. The CTR measurement using the I/O pin overloading seems to work fine. For several standard opto couplers with BJT output I get reasonable values matching manual measurements. For example the BJT's hFE measurement shows 1 while the CTR is 260% (PC817). I've also tested Darlington opto couplers (4N32) with success. The hFE is 9 while the CTR is 2070% (I/O pin current is 71mA!). The way the CTR is measured decreases the LED's I_f with an increasing I_e, which provides us with a larger headroom for the maximal possible CTR. For the Darlington type above I_f decreases from 5mA to about 3.5mA. Let's see what the outcome of Mauro's manual measurements is going to be. I'm curious about that. And I have to get some MOCs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: aknaydenov on March 03, 2016, 08:44:46 am
Hello people,

I stupidly killed my MEGA 328P ESR meter I gout from ebay, by forgetting to discharge a capacitor before measuring it. Do you have any idea if I can get somewhere spare programmed ICs? Or the code? If I manage to get a colleague to program it for me?

Thanks and best regards,
Alexander
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 03, 2016, 10:34:23 am
I stupidly killed my MEGA 328P ESR meter I gout from ebay, by forgetting to discharge a capacitor before measuring it. Do you have any idea if I can get somewhere spare programmed ICs? Or the code? If I manage to get a colleague to program it for me?

For the ATmega 328P you could go to the next best electronics shop and for the firmware please see https://github.com/svn2github/transistortester/tree/master/Software and choose trunk (k-firmware) or Markus (m-firmware), whichever you prefer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: aknaydenov on March 04, 2016, 05:57:30 pm
Thank you for the quick reply! I will read a bit and learn how to do the programming.
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on March 05, 2016, 03:43:06 am
@aknaydenov,

Here you will find an excellent video regarding editing and compiling of firmware. Look into the HELP folder.
Also a lot of precompiled firmware for many of the models available on ebay etc.

https://yadi.sk/d/yW8xa5NJgUo5z

You may put here the ebay link from where you purchased it so that people can help you identify the correct firmware.

These guys at eevblog are really helpful. I wish them all good.

Cheers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 05, 2016, 02:14:00 pm
micro88, thanks for the reference. However, I'm wary of downloading from miscellaneous locations, especially file sharing sites.

This repository is well organized and the inclusion of photos for model identification is a nice touch. Can anyone else vouch for this collection?
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on March 05, 2016, 02:42:14 pm
I had dropped and damaged my MK-328 tester . I used the firmware files from this repository to retrieve it successfully.
Have not tried the other models since I don't have those .
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 05, 2016, 03:08:55 pm
Can anyone else vouch for this collection?
This storage was created by me and am responsible for his contents. You have to me questions? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 05, 2016, 04:14:56 pm
Thanks indman. No questions at this time. I hadn't seen this source before, so I was being cautious. As I mentioned, it's nicely organized and the photos are helpful for identifying the various models.
Title: Re: $20 LCR ESR Transistor checker project
Post by: luma on March 06, 2016, 07:30:41 pm
@aknaydenov,

Here you will find an excellent video regarding editing and compiling of firmware. Look into the HELP folder.
Also a lot of precompiled firmware for many of the models available on ebay etc.

https://yadi.sk/d/yW8xa5NJgUo5z
What a great resource!  I'm waiting for the shipment of what appears to be the "M328Kit" variant and this should be helpful in getting the latest firmware setup.   I might have missed something (I often do), but I had to navigate through each of the model's folders to find photos in order to identify which board I'm using.  If I might make a suggestion - a main-page picture of the various boards might be helpful to visually identify which variant we're dealing with.

Thanks for putting this together and sharing it here.
Title: Re: $20 LCR ESR Transistor checker project
Post by: luma on March 06, 2016, 08:47:00 pm
Now that I'm re-reading things, I'm not 100% sure I've identified the correct variant.  I ordered this thing (http://www.ebay.com/itm/231859041626), which is sold as the M12864.  I've seen mention of it elsewhere in this thread.  Where would I find the firmware for this specific unit?
Title: Re: $20 LCR ESR Transistor checker project
Post by: i_cant_read on March 06, 2016, 10:50:34 pm
Hey folks,

I got that DIY M12864 kit from Banggood(http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html))
As pretty much all Testers came it with an old firmware. I am a completly beginner when it comes to µC so please dont expect me to know everything already^^
I am having difficulties with updating the firmware. I think i read somewhere that folder called mega328_st7565_kit is the right one. I am using a USBtiny as a programmer.
So i opend up cmd and gave it the direction where i saved the .hex and .eep then i typed in:
avrdude -c usbtiny -p atmega328p -U flash:w:TransistorTester.hex \ -U eeprom:w:TransistorTester.eep
it did everything without an error but when i put the µC back into the socket, give it power and pressing the encoder the display lights up but it only shows that big black square(every pixel lights up).
so what did i do wrong or forgot to do? hope you guys can help me^^

EDIT: I might have found what i forgot, when putting the µC on breadboard, it needs a external 8MHz crystal right?^^ dang it, totally forgot that, or isnt that the problem?
Title: Re: $20 LCR ESR Transistor checker project
Post by: demetris on March 06, 2016, 10:56:33 pm
Maybe you should check the fuses too
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 06, 2016, 11:08:35 pm
Let's see what the outcome of Mauro's manual measurements is going to be. I'm curious about that. And I have to get some MOCs.

Hi Markus, I think i'm missing something...
I made few measurement, but first of all I think I need to understand which is the setup that will give us the most useful results.

I verified with LTSpice which is the configuration to perform the manual measurements emulating the M12864 (see attachment) but even though for simple optocouplers like PC123, 4N35 or L817, as expected I manual measured a CTR really close to the one measured by my M12864 Kit, I don't know how the M12864 is measuring the darlington. Where are coming from the 71mA you are mentioning??

BTW this are the measurement so far:

Model     If                     Ic                     CTR                   hFE M12864
PC123   0.005702985   0.006419403   112.5621565   0.92
PC123   0.005704478   0.005997015   105.1282051   0.69
PC123   0.005702985   0.006285075   110.2067522   0.78
PC123   0.005702985   0.006316418   110.7563465   0.95
PC123   0.005704478   0.006316418   110.7273679   0.83
4N35    0.005704478   0.00571791     100.2354788   0.75
4N35    0.005698507   0.005491045   96.35935045   0.68
4N35    0.0057             0.005908955   103.6658811   0.83
4N35    0.005704478   0.00569403     99.81684982   0.75
4N35    0.005704478   0.005459701   95.70905285   0.65
L817B   0.005689552   0.006843284   120.2780693   1.33
L817B   0.005704478   0.006934328   121.559393     1.31
L817B   0.005685075   0.007050746   124.022053     1.25
L817B   0.005698507   0.006953731   122.0272394    1.25
L817B   0.00568806     0.007010448    123.2484912   1.11

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 06, 2016, 11:29:37 pm
avrdude -c usbtiny -p atmega328p -U flash:w:TransistorTester.hex \ -U eeprom:w:TransistorTester.eep

You can choose one of the following firmware variants:

m-firmware (it need to be compiled but worth it)
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)

k-firmware (already compiled even though to enable specific options you will have to rebuild it anyway)
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)


The complete string to program also the fuses should be:

avrdude -c usbtiny -p m328p -B 0.5 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: i_cant_read on March 06, 2016, 11:42:32 pm
avrdude -c usbtiny -p atmega328p -U flash:w:TransistorTester.hex \ -U eeprom:w:TransistorTester.eep

avrdude -c usbtiny -p m328p -B 0.5 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

Mauro

Hi thank you for the string^^
When i try using it tho, this message shows up:
 initialization failed, rc=-1
         Double check connections and try again, or use -F to override
         this check.

i didnt connected a external crystal so is that why this message pops up? dont have the capacitors on hand for it and its too late to desolder the 2 from the board, so going to do that tomorrow
just wanted to know if thats the error^^
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on March 07, 2016, 02:27:27 am
Yes, if the fuses are set for an external crystal as they probably are if you have a crystal in your tester, you will also need a crystal and 22pF capacitors to program it on a bread board.
Graham


i didnt connected a external crystal so is that why this message pops up? dont have the capacitors on hand for it and its too late to desolder the 2 from the board, so going to do that tomorrow
just wanted to know if thats the error^^
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 07, 2016, 09:51:43 am
If I might make a suggestion - a main-page picture of the various boards might be helpful to visually identify which variant we're dealing with.
Hi! I have already realized your offer. You can look at result. Thanks! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 07, 2016, 11:18:26 am
Hi Markus, I think i'm missing something...
I made few measurement, but first of all I think I need to understand which is the setup that will give us the most useful results.

I verified with LTSpice which is the configuration to perform the manual measurements emulating the M12864 (see attachment) but even though for simple optocouplers like PC123, 4N35 or L817, as expected I manual measured a CTR really close to the one measured by my M12864 Kit, I don't know how the M12864 is measuring the darlington. Where are coming from the 71mA you are mentioning??

Thanks for the measurements, Mauro! The common collector based hFE measurement is your circuit diagram with R1 = 680,  R2 = 0 and R3 = 680. If I_b is very low (assuming a Darlington) R1 is changed to 470k, which won't light the LED obviously. The issue with that test circuit is that the LED's current is limited by two times 680 Ohms and I_e causes a voltage drop across R3 too. So the LED's current will decrease even more, resulting in a quite low current. Most opto couplers got their optimal CTR around 5mA I_f. That explains why the hFE values are mostly lower than your measured CTR values. But they give a usable indication.

A Darlington output stage makes the mismatch worse, because the output current is limited by R3 (I = 5V / 680 Ohms =  7mA). For a high CTR the tester can't get proper values. When removing R3 and just using the MCU's internal pin driver resistance (20 Ohms) things become better but the pin will be overloaded. The example with 71mA is an opto coupler with a CTR of around 2000% at an I_f of about 3.5mA (3.5mA * 20 = 70mA).
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 07, 2016, 04:02:47 pm
The common collector based hFE measurement is your circuit diagram with R1 = 680,  R2 = 0 and R3 = 680.

Do you mean that the firmware is using PC2 as output for the collector current?
PB0 for the Led current trough R1 680 and you are reading the voltage on PC1 to calculate the current on the emitter?
The difference between If and Ie will give us Ic to calculate the CTR...

As you can see on my LTSpice diagram I was considering only the PBx as possible outputs...

If I_b is very low (assuming a Darlington) R1 is changed to 470k, which won't light the LED obviously. The issue with that test circuit is that the LED's current is limited by two times 680 Ohms and I_e causes a voltage drop across R3 too. So the LED's current will decrease even more, resulting in a quite low current. Most opto couplers got their optimal CTR around 5mA I_f. That explains why the hFE values are mostly lower than your measured CTR values. But they give a usable indication.

Yes, this is also my assumption on the measurements.

A Darlington output stage makes the mismatch worse, because the output current is limited by R3 (I = 5V / 680 Ohms =  7mA). For a high CTR the tester can't get proper values. When removing R3 and just using the MCU's internal pin driver resistance (20 Ohms) things become better but the pin will be overloaded. The example with 71mA is an opto coupler with a CTR of around 2000% at an I_f of about 3.5mA (3.5mA * 20 = 70mA).

Again I think this is what I'm missing:
Do you mean that the firmware is using PC2 as output for the collector current or we need to remove R3 on my diagram that means R5 on the M12864 schematic??

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: i_cant_read on March 07, 2016, 05:12:53 pm
avrdude -c usbtiny -p atmega328p -U flash:w:TransistorTester.hex \ -U eeprom:w:TransistorTester.eep

avrdude -c usbtiny -p m328p -B 0.5 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

Mauro

hi its me again, i now installed a 8MHz crystal+22pF capacitors when programming, but it still shows the same error message as before when i try your code :/

EDIT: alright its working now :) was probably a loose connection or something because after i rewired everything it worked. the ttester is working now~ thank you very much for your help :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 07, 2016, 05:17:44 pm
Do you mean that the firmware is using PC2 as output for the collector current?
PB0 for the Led current trough R1 680 and you are reading the voltage on PC1 to calculate the current on the emitter?
The difference between If and Ie will give us Ic to calculate the CTR...

The pin numbers are relative ;) The firmware uses the ADC port pin which it thinks it's the collector and sets the pin to output mode and high level. Yes, the LED's current is measured using R1 as a current shunt, but the relation between If and Ie is the CTR.

Again I think this is what I'm missing:
Do you mean that the firmware is using PC2 as output for the collector current or we need to remove R3 on my diagram that means R5 on the M12864 schematic??

Yes, and R2 and R3 are both disabled. Anyway, there's still the resistance of the MCU's pin driver which is around 20 Ohms. That internal resistance is measured by the self-adjustment and considered where it matters. In the case of the CTR measurement the internal resistance (R3) is used a current shunt. Since it's facing Gnd it will give us the benefit of a low voltage below the internal bandgap reference, i.e. we get an ADC resolution of 1mV instead of the standard 5mV (5V Vcc used as reference).
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 08, 2016, 12:34:42 am
Ok, now it make sense  :)

I measured some darlingtons with VLed=VC=5V, RLed=680, RE=0 and RC=20. (cathode and emitter shorted)
This is what I got:

Model   If                   Ic           CTR                    hFE M12864
4N33   0.005722388   0.085   1485.393845   7.64
4N33   0.005679104   0.0825   1452.693824   5.98
4N33   0.005697015   0.1065   1869.400052   10.3
4N33   0.005695522   0.0895   1571.409853   7.34
4N33   0.005725373   0.088   1537.017727   6.54
4N33   0.00571791   0.0875   1530.2793   7.15

With the same setup I measured also a 4N35.

Model   If                   Ic           CTR                    hFE M12864
4N35   0.005714925   0.009   157.4823714   0.83

This one with RC=680 gave me a CTR of 110

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 08, 2016, 10:36:03 am
I measured some darlingtons with VLed=VC=5V, RLed=680, RE=0 and RC=20. (cathode and emitter shorted)

Thanks for the additional measurements!

With the same setup I measured also a 4N35.

Model   If                   Ic           CTR                    hFE M12864
4N35   0.005714925   0.009   157.4823714   0.83

This one with RC=680 gave me a CTR of 110

The common collector hFE measurement also uses RE=680 Ohms (shared with the LED's cathode). That's why the hFE has to be taken with caution. Another point to remember is that the CTR has a non-linear relation to If. The CTR has a peak at some If and also changes with the ambient temperature. Lot's of fun :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 08, 2016, 02:30:26 pm
The common collector hFE measurement also uses RE=680 Ohms (shared with the LED's cathode). That's why the hFE has to be taken with caution. Another point to remember is that the CTR has a non-linear relation to If. The CTR has a peak at some If and also changes with the ambient temperature. Lot's of fun :)

Yes, that's why I played a bit with LTSpice, plotting the curves to verify the expected CTR with my setup.
It was really easy to slightly change the CTR just placing a finger on the component during the measurements :)
Since for the darlingtons test, current is quite high and the component self heat a bit, I left the components settle for few seconds to have a stable reading.

Yes it was fun :-DMM

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: luma on March 08, 2016, 03:06:40 pm
Hi! I have already realized your offer. You can look at result. Thanks! :)

Wow man, that's very helpful.  Thanks for making this happen, this resource will be useful for a beginner like me!
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 13, 2016, 06:52:54 pm
Hi, I need some help.  I have one of this testers, I wired to it a rotary encoder with a programmer and I am trying to reflash it. 

I found here this firmware called mega328_st7565_kit and my understanding was that it is the latest firmware with the encoder enabled.  The flashing goes smoothly without any problems.  However, the tester doesn't work, I have blank screen. 

I guess this firmware is wrong.  Can someone please provide a link for the correct firmware with the rotary encoder enabled.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: gorgamin on March 13, 2016, 09:01:42 pm
Hi, I need some help.  I have one of this testers, I wired to it a rotary encoder with a programmer and I am trying to reflash it. 

I found here this firmware called mega328_st7565_kit and my understanding was that it is the latest firmware with the encoder enabled.  The flashing goes smoothly without any problems.  However, the tester doesn't work, I have blank screen. 

I guess this firmware is wrong.  Can someone please provide a link for the correct firmware with the rotary encoder enabled.

Thanks

Check the guide by tom666 here:

https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/ (https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/msg892975/#msg892975)

Use the "Flash K-version (v1.12kr647)" firmware.


Can I ask for a schematic and part number of the rotary encoder you used?

Let me know how it goes^^
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 13, 2016, 09:53:48 pm
@gorgamin, I am getting closer.  I flashed my tester with firmware v1.12k_r453_EN and now my tester is working (v. 1.12k) but the rotary encoder still doesn't work.  I don't know if this version has the encoder enabled or not.  Do you have a link for the v1.12kr647 firmware?  Does anyone has a link to firmware version that the encoder is enabled?

This is the encoder I am using http://www.aliexpress.com/item/Rotary-Encoder-Module-Brick-Sensor-Development-for-arduino-Dropshipping-KY-040/32598943217.html (http://www.aliexpress.com/item/Rotary-Encoder-Module-Brick-Sensor-Development-for-arduino-Dropshipping-KY-040/32598943217.html), I just removed it from the board it came with and mounted it with the required resistors on my tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 14, 2016, 02:45:08 am
@Tom666 Hi,

I updated my tester with firmware v1.12k_r453_EN I found in one of your earlier posts here and it seems to work great.  Now I am trying to add a rotary encoder to it as you can see in the pictures above.  I am wondering if you have a complied version of this firmware with the rotary encoder enabled.  In any case, I would like the Makefile for it so I can play with it and learn how to compile it myself with some other changes.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: tino_so on March 14, 2016, 03:32:02 am
I am also thinking of adding an encoder to one of the testers I have. I found some pre-compiled versions here, I think most would have the encoder available by default:

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)

One can use the "download tar ball" link at the bottom of the page to get the code, so you can brew your own, or drill in to one of the folders that have a version that may match your hardware, all ready to go and try to load it with avrdude, to see how it works.

This is the project page:

http://www.mikrocontroller.net/articles/AVR_Transistortester (http://www.mikrocontroller.net/articles/AVR_Transistortester)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 14, 2016, 07:28:55 am
I tried several of the compiled firmware version from that archive, my tester worked but not the rotary encoder.  If you find any of the compiled firmware that works with this LRC-T4 tester and the encoder, I would appreciate to know which one worked.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on March 14, 2016, 08:26:02 am
... I am wondering if you have a complied version of this firmware with the rotary encoder enabled.  In any case, I would like the Makefile for it so I can play with it and learn how to compile it myself with some other changes.

Try this freshly compiled version (rotary encoder is enabled on the ports PD1 and PD3):
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on March 14, 2016, 08:51:51 am
Can I ask for a schematic and part number of the rotary encoder you used?

See attached picture from the official manual (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/).

Rotary encoder can be purchased on eBay:
http://www.ebay.com/itm/141887440223 (http://www.ebay.com/itm/141887440223)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 14, 2016, 09:03:08 am
... I am wondering if you have a complied version of this firmware with the rotary encoder enabled.  In any case, I would like the Makefile for it so I can play with it and learn how to compile it myself with some other changes.

Try this freshly compiled version (rotary encoder is enabled on the ports PD1 and PD3):
Hi Tom, thanks a lot! Works perfectly now!!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on March 14, 2016, 10:41:13 am
I mounted version 659 - 7565 kit and will not work now does not work with the previous fw 627.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 14, 2016, 12:18:32 pm
I mounted version 659 - 7565 kit and will not work now does not work with the previous fw 627.

Which clone do you got? Which firmware version was running before?
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on March 14, 2016, 01:31:02 pm
 mega328_st7565_kit/ Rev 659.
Rev627 had before install new Rev659 and now nothing works

(http://img.banggood.com/images/2014/xiemeijuan/07/SKU263599/DSMD.jpg)


Buffer Rev.659

Buffer content from address: 00000000h, to address: 0000010Fh
Address        +0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +A +B +C +D +E +F   0123456789ABCDEF
-------------------------------------------------------------------------------
0000000000 2D C6 00 00 3D C6 00 00 3B C6 00 00 39 C6 00 00     -Æ..=Æ..;Æ..9Æ..
0000000010 37 C6 00 00 0C 94 1D 27 33 C6 00 00 0C 94 B0 0C     7Æ...”.'3Æ...”°.
0000000020 2F C6 00 00 2D C6 00 00 0C 94 3F 1D 0C 94 01 27     /Æ..-Æ...”?..”.'
0000000030 0C 94 0F 27 0C 94 19 1D 23 C6 00 00 21 C6 00 00     .”.'.”..#Æ..!Æ..
0000000040 0C 94 DB 26 1D C6 00 00 1B C6 00 00 19 C6 00 00     .”Û&.Æ...Æ...Æ..
0000000050 17 C6 00 00 0C 94 B1 0C 13 C6 00 00 11 C6 00 00     .Æ...”±..Æ...Æ..
0000000060 0F C6 00 00 0D C6 00 00 B2 00 A9 00 A0 00 10 08      .Æ...Æ..².©. ...
0000000070 40 7E 01 01 3E 01 01 3E 01 01 3E 01 01 7E 40 40      @~..>..>..>..~@@
0000000080 18 00 07 20 08 08 08 F8 00 00 00 20 60 A0 3F A0       ... ...ø... ` ?
0000000090 60 20 02 02 02 FF 02 02 02 10 10 10 1F 00 00 00       ` ...ÿ..........
00000000A0 07 08 FF DB BD B5 B5 CB FF 07 08 FF BB 9D AD AD       ..ÿÛ½µµËÿ..ÿ»--
00000000B0 B3 FF 07 08 FF FF F7 FB 81 FF FF 10 10 05 08 F8          ³ÿ..ÿÿ÷ûÿÿ....ø
00000000C0 78 38 58 88 09 10 03 08 1C 3E 7F 0D 08 07 10 FF      x8Xˆ.....>.....ÿ
00000000D0 81 81 81 F1 E1 C1 FF 40 40 40 47 43 41 0D 08 01      ñáÁÿ@@@GCA...
00000000E0 10 FF FF 11 08 03 10 F1 E1 C1 47 43 41 0E 00 08      .ÿÿ....ñáÁGCA...
00000000F0 20 21 21 12 20 60 E0 E0 E0 FE FE 04 02 01 00 01      !!. `àààþþ.....
0000000100 03 7F 7F 21 C2 C4 C4 C0 40 94 84 00 07 03 01 02     ...!ÂÄÄÀ@”„.....

Buffer Rev. 627

Buffer content from address: 00000000h, to address: 0000010Fh
Address        +0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +A +B +C +D +E +F    0123456789ABCDEF
-------------------------------------------------------------------------------
0000000000 74 72 61 6E 73 69 73 74 6F 72 74 65 73 74 65 72        transistortester
0000000010 2F 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       /...............
0000000020 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       ................
0000000030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       ................
0000000040 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       ................
0000000050 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       ................
0000000060 00 00 00 00 30 30 30 30 37 35 35 00 30 30 30 30       ....0000755.0000
0000000070 30 30 30 00 30 30 30 30 30 30 30 00 30 30 30 30      000.0000000.0000
0000000080 30 30 30 30 30 30 30 00 31 32 36 35 31 33 35 36      0000000.12651356
0000000090 32 34 36 00 30 30 31 35 33 36 36 00 35 00 00 00      246.0015366.5...
00000000A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       ................
00000000B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       ................
00000000C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       ................
00000000D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       ................
00000000E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       ................
00000000F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00       ................
0000000100 00 75 73 74 61 72 00 30 30 76 69 65 77 76 63 00       .ustar.00viewvc
Title: Re: $20 LCR ESR Transistor checker project
Post by: jayesjay on March 14, 2016, 02:11:35 pm
I'm desperate! How can I reset the display contrast? The screen lights up, but the contrast is nil so no characters appear - the checker is now useless.

I have an implementation of the transistor checker with one push button - it was working fine until I played with the contrast control. It went down through 38 or so, and now there is no display of black characters on the bright screen.

I have tried disconnecting the battery for several minutes. Pressing the button after reconnecting, the display is unchanged.
I apologise if I have hit the wrong forum, or thread, but I am new here, it's a big forum, and I am desperate!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 14, 2016, 03:42:57 pm
mega328_st7565_kit/ Rev 659.
Rev627 had before install new Rev659 and now nothing works

Could you please a little bit more specific. Is the LED lit when powered on? Does the display show anything?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 14, 2016, 03:48:17 pm
I'm desperate! How can I reset the display contrast? The screen lights up, but the contrast is nil so no characters appear - the checker is now useless.

Several posts ago there's a recipe to enter the contrast menu. Otherwise you can flash a new firmware (will set the contrast's default value).
Title: Re: $20 LCR ESR Transistor checker project
Post by: klaus11 on March 14, 2016, 03:55:01 pm
mega328_st7565_kit/ Rev 659.
Rev627 had before install new Rev659 and now nothing works

Could you please a little bit more specific. Is the LED lit when powered on? Does the display show anything?

Yes Led powerd on, shows hundreds of scribbles
Title: Re: $20 LCR ESR Transistor checker project
Post by: jayesjay on March 14, 2016, 04:00:57 pm
Thanks for prompt response.

The display lights up, as normal when test button is pressed. The characters on the screen, which should be "black" are missing as the contrast has been adjusted, in error, to be very low.

This happened when I tried out more functions (component test) than I normally use via the display.
I pressed the test button to get the menu. Scrolled down with short presses to get to contrast, and then a long press to activate this.
A number appeared, something like 38. I pressed the test button and noticed that the number changed one way, I can't remember if it increased or decreased only by 3 or 4 and the contrast suddenly went from OK to nil.

In vain I tried disconnecting the battery and leaving the module for a while. I don't think that would help as I assume some digital word has been set in memory.

As I had taken a note of the menu items, I have tried the long press, so the menu should be there, and short pressed to hopefully arrive at the 9th item, contrast, on that menu. But since I don't know how the test button is used to make the contrast adjustment. I can't see how that can help.

I don't think I have the capability to revamp software, although I could do simple things like shorting a pin.

The forum is telling me I have two new posts to read, but I can't see how to get to them, so I will post tghis anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jayesjay on March 14, 2016, 05:29:20 pm
I've done some more testing. I noted the results of a search which brought up some ideas - basically either re-flashing firmware - no, I can't go down that route - or trying to locate the contrast item in the menu by trying presses. I have done that, but with no result.
 According to my list, the menu items are, when enabled on the display: MENU/Switch off/Transistor/Frequency/F-generator/10-bit.../C+ESR.../Rotary encoder/Selftest/Contrast/Showdata/switch off.....

Further, in the absence of a convenient scope (big one upstairs!), I put a amplifier input across pins 1 and 2, (line in) and listened to the sound as I went through the menu. I got a series of short burps for each menu position, and no tones which I hoped would be output at the appropriate menu item. Or are they out of the audio range?  I would expect output signal after one long press/ 3  and 4 short presses, (and contrast after 4 more short presses.

Considering a new unit is less than £10, it's got to the stage where maybe it isn't worth any more effort. I really don't need the item, I bought it as it is a nice item for its price.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Godzil on March 14, 2016, 06:42:23 pm
I've bought one of the chinese clone with a case and I'm really happy with it, just for the fun, I may try to add French as a language in the code repository.. :)

Oh and I've notices a funny misspell in the chinese case warning about caps: "

"Attention: Allways be shure to discharge capacitors"

and instantly though, haha Chinglish is always so fun, unless I see the original and official documentation of the tester... To find that they cut and past that from this documentation :D

I don't know who to tell, but the documentation is full of "shure". I'm not sure that it's correct... :D (it should be corrected)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jayesjay on March 14, 2016, 11:04:12 pm
My son says he can flash the firmware - he has the gear. Where can he get  the program from?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 15, 2016, 12:47:33 pm
Yes Led powerd on, shows hundreds of scribbles

Have you also updated the EEPROM?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 15, 2016, 10:52:27 pm
Hi, I need some expert help.  So far I mastered the flashing of new firmware on my tester (LCR-T4).  Now I am trying to figure out how to compile the firmware.

I am using the transistortester-trunk.tar.gz as the source code and the WinAVR-2010110 for the compiler.  Recently I received from Tom666 new firmware version LCR-T3,4_v1.12k_r660_ENC13 with the rotary encoder enabled and that firmware works perfectly on my tester with a rotary encoder.

I was trying to recompile the firmware with the Makefile that was included with the above firmware as an exercise.  During the compilation the program was 105.6% full and the new hex file size is 96KB compare to the original hex file of 83KB.  When I try to flash the new firmware I created I am getting Error: address0x8010 out of range at line 2049.  Any idea what is wrong?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on March 16, 2016, 07:35:42 am
During the compilation the program was 105.6% full and the new hex file size is 96KB compare to the original hex file of 83KB.

You need update a compiler:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg825078/#msg825078 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg825078/#msg825078)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 16, 2016, 06:47:36 pm
Hi Tom, it works perfectly now!  You have been a great help! 

I wish there would be some sort of a "sticky" to answered common problems and questions.

Give a Man a Fish, and You Feed Him for a Day. Teach a Man To Fish, and You Feed Him for a Lifetime!
Title: Re: $20 LCR ESR Transistor checker project
Post by: nowlan on March 17, 2016, 12:35:53 pm
Hello, considering getting one of these ESR kits to build. Had a look on bangGood, and there are a few to choose from.
Can someone recommend the darling? Is bangGood best bet, or aliexpress/ebay offer better ones or prices?


M328 LCD 12864 Transistor Tester DIY Kit Diode Triode Capacitance LCR ESR Meter $22.85au
http://www.banggood.com/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-p-1041588.html (http://www.banggood.com/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-p-1041588.html)

DIY M12864 Graphics Version Transistor Tester Kit LCR ESR PWM $25.67 (cant see difference)
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

DIY M12864 Graphics Version Transistor Tester Kit LCR ESR PWM With Case $31.58
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)
is the case worth $9 more. Seem to recall allignmnt issues.

GM328A Transistor Tester Graphic Wave Signal LCRRLCPWMESR Meter Inductance $20.44
http://www.banggood.com/GM328A-Transistor-Tester-Graphic-Wave-Signal-LCRRLCPWMESR-Meter-Inductance-p-997582.html (http://www.banggood.com/GM328A-Transistor-Tester-Graphic-Wave-Signal-LCRRLCPWMESR-Meter-Inductance-p-997582.html)

DIY Multifunction Transistor Tester Kit For LCR ESR Transistor PWM Signal Generator M328 $15.53
http://www.banggood.com/DIY-Meter-Tester-Kit-For-Capacitance-ESR-Inductance-Resistor-NPN-PNP-p-929603.html (http://www.banggood.com/DIY-Meter-Tester-Kit-For-Capacitance-ESR-Inductance-Resistor-NPN-PNP-p-929603.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Votality on March 17, 2016, 01:19:15 pm

Hello, considering getting one of these ESR kits to build. Had a look on bangGood, and there are a few to choose from.
Can someone recommend the darling? Is bangGood best bet, or aliexpress/ebay offer better ones or prices?


M328 LCD 12864 Transistor Tester DIY Kit Diode Triode Capacitance LCR ESR Meter $22.85au
http://www.banggood.com/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-p-1041588.html (http://www.banggood.com/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-p-1041588.html)

DIY M12864 Graphics Version Transistor Tester Kit LCR ESR PWM $25.67 (cant see difference)
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

DIY M12864 Graphics Version Transistor Tester Kit LCR ESR PWM With Case $31.58
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)
is the case worth $9 more. Seem to recall allignmnt issues.

GM328A Transistor Tester Graphic Wave Signal LCRRLCPWMESR Meter Inductance $20.44
http://www.banggood.com/GM328A-Transistor-Tester-Graphic-Wave-Signal-LCRRLCPWMESR-Meter-Inductance-p-997582.html (http://www.banggood.com/GM328A-Transistor-Tester-Graphic-Wave-Signal-LCRRLCPWMESR-Meter-Inductance-p-997582.html)

DIY Multifunction Transistor Tester Kit For LCR ESR Transistor PWM Signal Generator M328 $15.53
http://www.banggood.com/DIY-Meter-Tester-Kit-For-Capacitance-ESR-Inductance-Resistor-NPN-PNP-p-929603.html (http://www.banggood.com/DIY-Meter-Tester-Kit-For-Capacitance-ESR-Inductance-Resistor-NPN-PNP-p-929603.html)


Glad I'm not the only one bewildered by all the variants. Question is which one is the best.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 17, 2016, 05:02:40 pm
There are several other variants actually and you can decide to build it following the schematic online or just buy a fully assembled device, you can have it with input protection or color display...
The best is the one that better fit your need.
Yes, I hate when someone use this sentence... If I knew my needs I was not writing on a forum...  :)

Seriously, to keep it simple, the first 3 you linked are the same. I choose the one with the case, as for me it worth it and the entire unit is very nice.
The last one is just an old version with 2 row LCD (I don't like this).
All the above are DIY but really easy to put together and all the components are really easy to replace (also the microcontroller) that you will easily destroy with a not discharged cap  :-BROKE BTW you can add input protection.

The remaining one is fully assembled, all the parts are SMD but it do not have the encoded that is nice to have to easily navigate trough the menus.

Again it is up to you to decide, but i'm really happy with this:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 17, 2016, 05:10:01 pm
I would pick this one if you can build it, it's a real KIT. 

M328 LCD 12864 Transistor Tester DIY Kit Diode Triode Capacitance LCR ESR Meter $22.85au
http://www.banggood.com/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-p-1041588.html (http://www.banggood.com/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-p-1041588.html)

If you cannot built it then look for one already assembled with a Rotary Encoder.  You can find all of them on AliExpress a few dollars cheaper.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 17, 2016, 05:11:06 pm
I'm surprised that there are so many on Banggood now. I got mine there some time ago and there was only one seller of the 12864 version. It was on sale at the time, so I bought it there rather than the other usual locations. I prefer the rotary input for better usability than a single pushbutton.

I initially wrote what mauroh did, but he hit the Post button before I did, so I'm trimming out the rest of what I had here.

(snip)

Regarding the case for the 12864, I didn't get it because I'm not keen on its aesthetics and dimensions. Personal preference, I'd say.

Finally, I'd stick with models that have a socketed Atmega328 microcontroller just in case you fry it, unless you're adept at replacing SMD ICs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 17, 2016, 06:59:20 pm
At first glance I was not taking the case, because with the case you will lose the green ZIF socket an the SMD pads, but I managed to keep the ZIF easily cutting the case and now I can use the super useful tweezers (bought separately) also for in-circuit testing and for SMD parts.

For the SMD components with 3 pins I made a simple adapter with a cutter but someone made a better adapter.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 17, 2016, 07:51:40 pm
Where did you find the blank adapter boards?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 17, 2016, 08:30:53 pm
Not my design, I found it on an old post of the german forum where the autors of the current firmwares are really actives:

http://www.mikrocontroller.net/topic/343407 (http://www.mikrocontroller.net/topic/343407)

As I stated my version is much more "doggy", see picture  :-+

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: kapuchy on March 20, 2016, 01:41:47 pm
Hi everyone,
I am going to use "Atmega328P 5V 16 MHz Arduino Pro Mini" as 2x16 LCD tester with these steps:
- remove original AREF capacitor and use smaller value 1 nF,
- connect LCD module, test button + resistor (PD7) , 2,5 V reference (PC4) and 6 resistors 1%,
- rebuild Markus 1.21 classic project to 16 MHz clock (WinAVR 20100110).

Should I do something additional?
Should I use ISP programmer (ISP connector + USBasp) or original Arduino bootloader via USB/RS232 TTL dongle?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 20, 2016, 02:53:10 pm
I am going to use "Atmega328P 5V 16 MHz Arduino Pro Mini" as 2x16 LCD tester with these steps:
- remove original AREF capacitor and use smaller value 1 nF,
- connect LCD module, test button + resistor (PD7) , 2,5 V reference (PC4) and 6 resistors 1%,
- rebuild Markus 1.21 classic project to 16 MHz clock (WinAVR 20100110).

Should I do something additional?
Should I use ISP programmer (ISP connector + USBasp) or original Arduino bootloader via USB/RS232 TTL dongle?

You could also use 1.21m trendy edition. Anyway, you need an ISP programmer since the Arduino boot loader will be overwritten. There's an Arduino version of some older m-firmware and a shield (Ardutester), but I don't know if that project is still alive. Maybe also add a rotary encoder?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 21, 2016, 08:33:32 am
I just added a relay for input protection on my LCR-T4 tester.   Upon careful examination of the suggested circuit in the originator's manual, I see a major design flaw of the relay driving circuit. 

The relay is driven with a bipolar transistor from the TL431 2.5v reference voltage through a 4.7k resistor.  The transistor base current would be (2.5-0.7)/4.7k=0.38mA.  To drive the transistor into saturation, the transistor collector current would be only 0.38*10=3.8mA.  You cannot find a 5v relay that will operate at <4mA!  The most sensitive small dip relay that I could find had a coil resistance of 167ohm which will draw 30mA at 5v.   Most other small relays I found, drew more than twice that.  Even if you could find a 5v relay that drew <4 mA then you could not sink the additional 0.38mA from the 2.5v reference and keep it within specs.  The TL431 needs a minimum of 1mA and without the extra base drive it barely meets it (2.5/2.2k=1.14mA).

Your best bet for the relay driver is using a small N Channel MOSFET like 2N7000 driven from the 5v.  If you insist on using a bipolar transistor as a driver, then drive it also from the 5v and not from the 2.5v reference and use a base resistor of 1k not 4.7k which will support relays that draw up to 45mA.  If your relay draws more than 45mA then you will have to decrease the base resistor even more.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on March 21, 2016, 08:53:41 am
Edited now that I am fully awake.....
The MCU obviously cannot pull PC4 up to 5V with the TL431 attached, so my original explanation was incorrect. I was a little to quick to explain that the suggested circuit works just fine as designed and my explanation was not correct. 

As Marcus pointed out, the error in your calculation is the hfe of the NPN. I don't think you could find a gp NPN with an hfe of only 10 and surely not a BC547.
A look at the data sheet indicates that typical characteristics would be that a collector current of 60 mA  would require a base current of a little more than 250uA

If your relay requires this much current you might want to consider connecting the collector to Ubat instead of Vcc as it is possible that the relay load would pull Vcc down during the measurement and significantly impact the measurement accuracy.

I have this installed as designed on three different testers and all works just fine with a gp NPN.. I think I used PN2222 or 2N3904 which can drive most any small, common relay.
Graham
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 21, 2016, 11:33:34 am
I just added a relay for input protection on my LCR-T4 tester.   Upon careful examination of the suggested circuit in the originator's manual, I see a major design flaw of the relay driving circuit. 

The relay is driven with a bipolar transistor from the TL431 2.5v reference voltage through a 4.7k resistor.  The transistor base current would be (2.5-0.7)/4.7k=0.38mA.  To drive the transistor into saturation, the transistor collector current would be only 0.38*10=3.8mA.

It won't work if your NPN only got a hFE of 10. A BC547A has 110-220, the B version has 200-450. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 21, 2016, 04:28:26 pm
The hFE you are talking about is NOT for VCE(sat).  The hFE of 100-450 is specified at VCE of 5v-10v depends on who is the manufacturer of this BC547. 

The hFE for VCE(sat) on this BC547 is specified at 20, most common transistors in the US like 2N3904 and PN2222, the hFE for VCE(sat) is always specified at 10.  Even if you use hFE as 20, you still don't have sufficient base current to activate the relay.
Title: Re: $20 LCR ESR Transistor checker project
Post by: spiderb on March 21, 2016, 05:19:54 pm
Hi all
I have the banggood DIY kit and have played with the Xtal test software.
I enabled 16 mz and it worked ok, I had changed the Xtal on the board
If I enable the WITH_XTAL option it starts up after programming but wont start after turning the power off
It will sometimes start after repeated presses of the button but sometimes the display is corrupted
If I disable the WITH_MENU option and leave the Xtal option enabled
it starts up every time, but I have noticed the screen for no component found
is corrupt, reading "N" on the top line and "damaged part" on the second line and the big question mark
The software came from the main site and was compiled and loaded with WinAvr-20100110
from the Yadi disk site.

I realise this is beta software and was wondering if anyone else had the same issues

Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 21, 2016, 05:54:12 pm
The hFE you are talking about is NOT for VCE(sat).  The hFE of 100-450 is specified at VCE of 5v-10v depends on who is the manufacturer of this BC547. 

The hFE for VCE(sat) on this BC547 is specified at 20, most common transistors in the US like 2N3904 and PN2222, the hFE for VCE(sat) is always specified at 10.  Even if you use hFE as 20, you still don't have sufficient base current to activate the relay.

Rule of thumb:
  I_b = I_e / hFE (non saturated)
  for saturation use 2 or 3 times I_b

Example (relay 40mA, hFE 200):
  40mA / 200 = 0.2mA
  2 * 0.2mA = 0.4mA

Please breadboard it and check what happens.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 21, 2016, 06:29:44 pm
With all due respect, "rule of thumb" are not part of any manufactures specs.  That is why EVERY bipolar transistor has a VCE(sat) specified at a specific Ic and Ib.  BTW, I am an EE with over 30 years of hardware design experience and I never heard this rule of thumb.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 22, 2016, 01:45:29 pm
With all due respect, "rule of thumb" are not part of any manufactures specs.  That is why EVERY bipolar transistor has a VCE(sat) specified at a specific Ic and Ib.  BTW, I am an EE with over 30 years of hardware design experience and I never heard this rule of thumb.

I'm looking at Fairchild's datasheet of the BC546/547/548/549/550 right now. Figure 1 depics the diagram of V_CE vs. I_C. There's a curve for I_B = 0.4mA. Let's go for I_C = 40mA (our relay) and we'll find a V_CE of about 0.7V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 22, 2016, 10:55:45 pm
Any curves on datasheets are typical and are not guaranteed at all.  Any solid design should be based on clearly specified parameters, especially the saturation region of a bipolar transistor which is very murky on these charts.  My point also is that it really doesn't cost you anything extra to do it right.  Sorry if I am being a little harsh.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on March 23, 2016, 12:55:16 am
With all due respect, "rule of thumb" are not part of any manufactures specs.  That is why EVERY bipolar transistor has a VCE(sat) specified at a specific Ic and Ib.

Which are listed as typical values, not absolute, guaranteed values, and can vary from transistor to transistor of the same batch.


Any curves on datasheets are typical and are not guaranteed at all.

As are most values listed on the datasheet. You sound like you think saturation is a single specific operating point, controlled by a single specific input value.


My point also is that it really doesn't cost you anything extra to do it right.

Says he who is not doing the work. Others have stated that the design works for them. If you can't figure it out you are free to implement it however you like on your board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Meth on March 24, 2016, 01:34:41 pm
I've had one of these for a while now and they are just great - thanks to all involved!
The unit I bought was a GM328A pre-built unit with the larger display for under £12 delivered, performed the rotary encoder mod and flashed the open source software.

I've got a couple of request for features that might be useful - I did build them in to my own unit but it would be nice if they were officially supported.
These may be supported but weren't in the build I'm currently running (~550)
1) Pull the SVN revision out to the screen at either boot or in the menu system - the software changes so quickly I forget which version I'm running!
2) When measuring a potentiometer display not only the wiper position but also the full range, or the difference between the two.

Thanks again!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2016, 02:12:03 pm
I've got a couple of request for features that might be useful - I did build them in to my own unit but it would be nice if they were officially supported.

Please send your modifications to Karl-Heinz (his email address is on the first page of his excellent documentation) for the k-firmware or to me for the m-firmware.

And a quick update on the m-firmware. I've tested several TRIAC type opto couplers and the detection works fine so far. Even a MOC3043 with the zero crossing circuit and a low inhibit voltage of about 5V is no problem. For BJT types the t_on/t-off delays are measured. Not very accurate, but it gives an indication. I think I'll release 1.22m at the weekend. Sorry, no hidden easter eggs :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Meth on March 24, 2016, 02:42:06 pm
No problem, I'll try and sort out a patch in the next few days.
For reference I've just taken some screen shots of what you see.

Edit: going to back to the source it looks like the potentiometer shows like that in the standard code anyway - the change I'd made (which I don't have a picture for) was to add the total resistance on the next line below.
I'll submit it anyway and leave it to Karl-Heinz's discretion :)

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 24, 2016, 07:11:15 pm
Welcome to the forum, Meth. I like your enhancements. Looking forward to seeing them incorporated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on March 25, 2016, 01:14:09 pm
Hi, guys! It has been a long time since my last post since I was very happy with the tester  ;D But, today I wanted to make it work from a single Li-Ion cell. I built a simple boost converter (3.7V-5V), and it works just fine; however the software I'm using complains about battery voltage being too low (3.8V) and won't even start the testing procedure. So, the question - is there any .hex available that will allow me to use the 3.7V cell?
 I'm not very good at programming, so I can't go and change the low battery threshold myself. I tried, but failed immediately  |O
P.S. I did hardware "hack" (sent a 2.5V to pin 28), works just fine. But that way I don't know what is battery voltage at a time. So, I ask for your help  :-[
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 25, 2016, 02:22:21 pm
For the k-firmware you can change the threshold voltage in the Makefile by changing BAT_POOR. For the m-firmware it's in config.h (also BAT_POOR).
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on March 25, 2016, 02:48:06 pm
I tried to do so. I'm using 'k' software with atmega328 and 16x2 LCD, so I went and opened Makefile in: trunk/mega328. I opened Makefile in Programmer's Notepad, changed BAT_POOR to 2900 (CFLAGS += -DBAT_POOR=2900). After I pressed "Make All" it did compile fine (exit code=0) so I flashed the uC, but it doesn't work, there's nothing on the screen. What did I do wrong? Maybe I need to include some files (.c or .h) before pressing "Make All"?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 25, 2016, 03:57:02 pm
Is the LED lit? Is there some brief output on the display or nothing at all? Does the tester stay powered on?
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on March 25, 2016, 04:35:12 pm
There's nothing appearing on the screen even for a split second. Maybe the project has been changed to accommodate large graphical displays so it won't work now with my boring 16x2 LCD? By the way in my build data bits 4-7 of the LCD are connected to PD0-PD3 on the Mega328, is this correct?  Yes, LED is lit and the device stays on. I can't even run a Proteus simulation, every .hex refuses to work
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on March 25, 2016, 04:55:49 pm
Please excuse me being a complete idiot  :-[ I used the wrong fuses, now it works excellent. I can't really be embarrassed any more, you guys (Karl and Markus) paid so much time&effort into making this and you did a GREAT job making it simple to modify, yet I still managed to fail, D'OH!
Title: Re: $20 LCR ESR Transistor checker project
Post by: kapuchy on March 25, 2016, 06:09:24 pm
Changing hex code isn't necesssary, you can also change value of one resistor (1:2 divider instead of 1:4 for battery voltage measurement)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrJohnnny on March 25, 2016, 09:30:45 pm
I'm aware of that, I did exactly the same to make it work (I mentioned about putting 2.5V (Vcc/2) onto PC5 of the Mega328 above). But that will give me bullshit readings, so I decided to do it the proper way  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hendrick on March 26, 2016, 01:56:52 am
I think I'll release 1.22m at the weekend.

B-but I just managed to flash to 1.21m...

I have some questions regarding compiling the m-firmware for the DIY M12864 kit (the red one with the rotary encoder):

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 26, 2016, 10:30:13 am
Yes and yes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ttcole1254 on March 26, 2016, 10:46:57 pm
I just got one of these, believe it is a clone but seems to work nonetheless.

I found a problem though when attempting to measure capacitors of any size. The larger the capacitor, the larger off it seems to be. It reads extremely high.

I tested a 1000 microfarad cap, got 3254 microfarads with 0.02 ohm ESR and 1.4% voltage loss
An 0.47 mic cap reads 520.5 nano, 10 ohm ESR and 2% VLoss.

The lower you go, the more accurate it becomes. An 0.01 mic cap reads 10.64 nano with a VLoss of 1%.

I attempted the self test procedure, and the values are a little better, but still way off on the larger capacitors. These caps were sitting in a drawer and were fully dead, so that couldn't have been it. I tested all resistors on the back, and found a 100k resistor was actually doing 55k. Replaced it with a new 100k, and the readings didn't change. Resistors test correctly, showing 1011 ohms for a 1000 ohm resistor attached. Not sure what the problem could be now, but I can always return it for a new one. Figured I would try and fix it first :P

Edit: Another thing because I know the crystal can affect the readings. It says 8 MHz, but I have no way to test that. No version number appears when booting it up, just "MTester" at the top.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on March 27, 2016, 03:36:20 am
Yes and yes.
Impressive !!!  :clap: :clap: :clap:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 27, 2016, 12:02:46 pm
I tested a 1000 microfarad cap, got 3254 microfarads with 0.02 ohm ESR and 1.4% voltage loss
An 0.47 mic cap reads 520.5 nano, 10 ohm ESR and 2% VLoss.

There's something wrong with your tester. The error normally increases to about 5% above 100µF.

Edit: Another thing because I know the crystal can affect the readings. It says 8 MHz, but I have no way to test that. No version number appears when booting it up, just "MTester" at the top.

It's a modified firmware version without the source code being available :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: ttcole1254 on March 27, 2016, 01:01:25 pm
Yeah I was worried it was a clone when no version appeared anywhere, not even in the self test. Shame something's wrong with it because the circuit is relatively simple as far as the component count, and all the resistors check out on a multimeter. Guessing it's either something wrong with the atmega or possibly a software glitch due to it being a modded clone. Also reflowed all solder on the board thinking it could've just been a bad connection somewhere.

It does have the ISP port and I do have an arduino uno I could use to program it. But if I do change the firmware and it doesn't fix it, I have no chance at returning it. Do any of you know where I could buy a new one running a non-modded firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 27, 2016, 05:22:22 pm
The semi-DIY versions typically come with unmodified/somewhat unmodified firmware these days. Here, for instance, is a popular version that's not too bad:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)
I still recommend reflashing as soon as you get it.

Reflowing these things is something I would do only as an act of desperation because, in my experience, resistors, while harder to destroy by heat than other components, tend to drift in value permanently when heated too much, and that's not good for the "precision" measurement resistors that are probably not so precise to begin with.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 27, 2016, 07:25:09 pm
Yeah I was worried it was a clone when no version appeared anywhere, not even in the self test. Shame something's wrong with it because the circuit is relatively simple as far as the component count, and all the resistors check out on a multimeter. Guessing it's either something wrong with the atmega or possibly a software glitch due to it being a modded clone. Also reflowed all solder on the board thinking it could've just been a bad connection somewhere.

Could be also wrong fuse bits, like using the internal RC oscillator instead of the external crystal. Component-wise there's not much to screw up, besides damaging the MCU by a charged cap.

It does have the ISP port and I do have an arduino uno I could use to program it. But if I do change the firmware and it doesn't fix it, I have no chance at returning it. Do any of you know where I could buy a new one running a non-modded firmware?

Actually any clone not running that MTester firmware. But it doesn't matter since you can flash one of both "official" firmwares as long as the display is supported.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hendrick on March 29, 2016, 04:49:17 am
Some questions about the m-firmware (I have the DIY M12864 kit, red pcb):
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 29, 2016, 05:02:12 am
Sounds like a bad or dirty encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 29, 2016, 10:16:55 am
Is the calibrating capacitor included in the kit not needed for the self-test/adjustment with the m-firmware?

For the m-firmware's self-adjustment you would check the cap three times at least (normal measurement) and then run the self adjustement. It's explained in the README file.

It seems my rotary encoder isn't responsive, when I rotate it slowly, it cycles through the menu but changing to the next menu item doesn't take the same number of turns, e.g. it might change after 1 turn but some times as many as 4 or more turns are needed. If I rotate it faster in a clockwise direction (at a constant rate), it cycles downwards through the menu but also it may decide to go upwards or even up then down again. Is this a firmware or hardware issue?

Have you set ENCODER_PULSES in config.h correctly? During the development of the rotary encoder support I've tested mostly ALPS encoders and I haven't got any feedback about issues with specific manufacturers or types yet. The algorithm detects Gray code violations and skips bad steps. A dodgy encoder maybe?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on March 29, 2016, 03:12:56 pm
Hello people.

for anybody using the EZM GM328A model, i have been running a thread for it here.
http://www.badcaps.net/forum/showthread.php?t=50720 (http://www.badcaps.net/forum/showthread.php?t=50720)

 :-/O   8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 03, 2016, 08:03:34 pm
Here is my final version.
Original LCR-T4 clone + Rotary Encoder + Protection Relay + Li-Ion battery + Charger with protection circuit + 5V Sep-Up Converter + Banana Sockets + Case.   Total cost <$20 (not including the battery) + at least a day of work, yes I am retired.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 03, 2016, 10:24:36 pm
is that the firmware i posted?
i asked for feedback on that so i could finetune it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 03, 2016, 10:54:25 pm
No, I ended up compiling my own.  I tried yours and had some problem, I don't remember now the problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 04, 2016, 04:53:49 am
Hi, I am having a problem with my tester and the rotary encoder, I don't know if that is a common problem.

If I am in the Menu selection and I turn fast the encoder it will sometimes lock the processor.  Turning the encoder fast back and forth locks it almost every time.  The display will be cleared and no matter what, I cannot turn off the tester.  The only way to turn it off is to remove the power or reset the processor.  Otherwise the tester works fine. 

I am wondering, is there a solution for it or just don't turn the encoder fast and add a reset switch (my battery is not accessible).
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 04, 2016, 06:38:46 am
can you upload your makefile.
and are you using PD1 & PD3 with the correct resistors?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 04, 2016, 06:58:28 am
Yes I am using PD1 & PD3, all my resistors are fine and the rotary encoder works OK.  Did you try to rotate your encoder back and forth fast? 

I had to rename my Makefile to Makefile.txt, it wouldn't let me attach a file without an extension.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 04, 2016, 05:05:54 pm
if i rotate the encoder fast, it just exit's from the menu.
i think that's intentional - something else to remove!

of course i/m not using the same encoder because yours looks like some type of arduino addon.
i'll go read your makefile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 04, 2016, 05:16:47 pm
well if your unit works - other than that issue,
i suspect what was wrong with the code i supplied was the encoder was running backwards, also the contrast was different (the questions i asked!).

the only other thing i noticed was the setting:
Quote
# The PULLUP_DISABLE option disable the pull-up Resistors of IO-Ports.
# To use this option a external pull-up Resistor (10k to 30k)
# from Pin 13 to VCC must be installed!
#CFLAGS += -DPULLUP_DISABLE
try enabling that option - you do have that pullup resistor.
the text refers to a dil package, on smd it's pin11
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 04, 2016, 06:05:46 pm
I just recompiled with the CFLAGS += -DPULLUP_DISABLE and I still have the same problem, if anything it is maybe worst.  I also noticed that I have the same problem not only when I am in the Menu selection mode but also in the regular testing mode. 

I am not sure, did you try to rotate your encoder back and forth fast?  Does your tester use the 328P SMD processor?  I noticed that all the testers sold with the encoder don't use the SMD processor.  I added my encoder to the SMD tester version.  As far as the encoders from China, I think they are all the same, mine was just assembled on a small board for the Arduino.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 04, 2016, 06:17:28 pm
interesting.
so i tried "back and forth fast" and it still exit's the menu,
but it also enters the menu from the regular screen!

and yes, i'm using an smd 328p mcu.

the chinese encoders are not all the same btw.
when i went to buy one i noticed that there are atleast 2 from different manufacturers on ebay.
one has a blue base section and the metal section looked very cheaply made,
the other is bright green and is much better quality IMO.
so i got the green one - it was about twice the cost btw - but still next to nothing. :)

i dont think the encoder can be blamed for a software lockup though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 04, 2016, 07:01:52 pm
I guess my encoder is the "cheap" one, $0.53 on Aliexpress.  BTW, mine also sometime would enter into the Menu mode from the regular screen when turning fast the encoder.  Just to make sure, I also tried to compile with encoder type "1" and the processor locked up immediately as soon as I turned it.

Hopefully some of the experts here will chime in with some ideas.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 04, 2016, 07:16:06 pm
The rotary encoder is in parallel with two display signals. Do you know which display signals?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 04, 2016, 07:20:29 pm
Yes, PD1 and PD3, on the Graphics display it goes to SI and S0.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 04, 2016, 07:30:52 pm
hey, does that rotary-pcb have the "button" totally isolated from the rotary function?
the pcb has 5 pins, but you should need 6.

once you get this fixed btw, you need to swap out the crystal for a 16MHz one - then you can enable the resonator&crystal testing function  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 04, 2016, 07:42:04 pm
Yes, PD1 and PD3, on the Graphics display it goes to SI and S0.

Serial In and Serial Out?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 04, 2016, 07:44:29 pm
no, he's linked to SI and A0
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 04, 2016, 07:47:50 pm
Of course I had to isolate the switch, one leg was grounded.  I should know what I am doing, I am only an EE.  Also I had to add the 2 series 1k resistors, the 2 10k pull ups were already on the board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 04, 2016, 07:50:14 pm
hey, does that rotary-pcb have the "button" totally isolated from the rotary function?
the pcb has 5 pins, but you should need 6.

A mechanical rotary encoder with push button usually has 5 pins, two for the push button and three for A, B and C(ommon).
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 04, 2016, 07:51:50 pm
hey, does that rotary-pcb have the "button" totally isolated from the rotary function?
the pcb has 5 pins, but you should need 6.

A mechanical rotary encoder with push button usually has 5 pins, two for the push button and three for A, B and C(ommon).

yes, but the pcb included pullup resistors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 04, 2016, 07:54:11 pm
Sorry the PD1 and PD3 goes to SI & A0 at least that what is says on the schematic.  I actually wired it directly to the processor pin 1 & 31
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 04, 2016, 08:15:45 pm
try desoldering one of the wires and see if you can still crash the cpu
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 04, 2016, 09:47:08 pm
in "config.h" is this:

Quote
// number of rotation steps to identify a fast rotation of rotary switch
#define FAST_ROTATION 10

try changing it to 100 or something to effectivly disable it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 04, 2016, 11:05:18 pm
I give up, it didn't make any difference.  Can you attach your eep, hex and makefiles maybe my source is somehow corrupt?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 04, 2016, 11:35:22 pm
try this.
i made some changes.
(to a lot more than the makefile)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 05, 2016, 12:09:20 am
Thanks but I cannot use your files as is because I am using now a Li-Ion battery.   Is that the firmware you are using now and it doesn't lock up when you rotate fast the encoder?  BTW, does you tester have the same graphics display as mine, maybe that is the problem.  Can you recompile it again with CFLAGS += -DBAT_POOR=3000 so I can try it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 05, 2016, 12:25:24 am
with 3v poor
 8)

to answer your questions,
i'm not using a T4,
the GM328A uses different pinouts, but the same display.
no crashes / lockups.

there is code to detect fast spins, maybe it's the problem - so i sabotaged it in the test file. :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 05, 2016, 02:00:08 am
Ok, I tried your version and the smallest movement of the encoder even not in the menu selection locks up the processor. 

Obviously there is some fundamental difference between your tester and mine.  I think I need some help from someone that is intimately familiar with the software.  I need to find out whether there is a bug with the software or something is wrong with my tester.  Like I said, except for the fast rotation of the encoder everything including the encoder itself is working fine.

Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 05, 2016, 02:34:29 am
have you tried compiling the trendy software from madires?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 05, 2016, 02:51:16 am
Do you have a link for this trendy software?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 05, 2016, 06:21:59 am
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/)

top folder is the trendy,
bottom folder is the K version your using.

before that, check your resistors on the encoder board with a meter.
i have a feeling they could be the cause.
Title: Re: $20 LCR ESR Transistor checker project
Post by: spiderb on April 05, 2016, 01:43:04 pm
I have several of these gadjets and my advice would be to try running it off a battery or a linear power supply. They do not like switch mode powers supplies at all
bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: Martini on April 05, 2016, 05:39:43 pm

Hello, considering getting one of these ESR kits to build. Had a look on bangGood, and there are a few to choose from.
Can someone recommend the darling? Is bangGood best bet, or aliexpress/ebay offer better ones or prices?


M328 LCD 12864 Transistor Tester DIY Kit Diode Triode Capacitance LCR ESR Meter $22.85au
http://www.banggood.com/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-p-1041588.html (http://www.banggood.com/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-p-1041588.html)

DIY M12864 Graphics Version Transistor Tester Kit LCR ESR PWM $25.67 (cant see difference)
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

DIY M12864 Graphics Version Transistor Tester Kit LCR ESR PWM With Case $31.58
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)
is the case worth $9 more. Seem to recall allignmnt issues.

GM328A Transistor Tester Graphic Wave Signal LCRRLCPWMESR Meter Inductance $20.44
http://www.banggood.com/GM328A-Transistor-Tester-Graphic-Wave-Signal-LCRRLCPWMESR-Meter-Inductance-p-997582.html (http://www.banggood.com/GM328A-Transistor-Tester-Graphic-Wave-Signal-LCRRLCPWMESR-Meter-Inductance-p-997582.html)

DIY Multifunction Transistor Tester Kit For LCR ESR Transistor PWM Signal Generator M328 $15.53
http://www.banggood.com/DIY-Meter-Tester-Kit-For-Capacitance-ESR-Inductance-Resistor-NPN-PNP-p-929603.html (http://www.banggood.com/DIY-Meter-Tester-Kit-For-Capacitance-ESR-Inductance-Resistor-NPN-PNP-p-929603.html)


Glad I'm not the only one bewildered by all the variants. Question is which one is the best.
I would add this one (http://www.aliexpress.com/item/New-Arrival-LCR-T4-ESR-Meter-Transistor-Tester-Diode-Triode-Capacitance-SCR-Inductance-New/32642022484.html) with the bigger screen and the push button for $9.35 assembled.
I actually saw this on aliexpress before finding this thread here.

I'd prefer a kit rather than an assembled unit but I also prefer to spend $9 rather than 15 (I know it's close to nothing in both cases but $9 is closer to nothing  ;D).
Is that one hackable into using a rotary encoder?
Will it display Vloss?


Or do you have another option (a complete kit available for a cheap-ish price) to propose?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 05, 2016, 06:01:45 pm
T4 is barebones design with no input protection.

the GM328A is much better - input protection is fitted and it has a set of flyleads for off-board testing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 05, 2016, 06:15:52 pm
I have several of these gadjets and my advice would be to try running it off a battery or a linear power supply. They do not like switch mode powers supplies at all
bill
I am very familiar with switch mode regulators.  The output of my step-up 5v regulator has less than 50mv p.p switching noise and I even bypassed the 5v right on the encoder. 

To eliminate anything else, I reverted back to the battery power and the 7805 regulator and I still have the same problem, turning the encoder back and forth, not even fast locks the processor.  Other than this problem, my tester including the encoder work fine.

I would like to hear from other people that have or added the rotary encoder and don't exhibit this problem.

Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 05, 2016, 06:53:09 pm
if your resistors are wrong, you could overload the pd1/3 pins when they are outputs.
that could drag the voltage down in the mcu and glitch it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: spiderb on April 05, 2016, 07:02:10 pm
I have the banggood diy and the clone with two switches on and I have found they do not like switch mode psus.  both have encoders fitted, both work fine on battery but play up on psus. What i have found is that it is better to run them on battery when programming them as both have fallen over after being programmed on psus even though they verified without error YMMV

bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 05, 2016, 10:11:16 pm
I have the banggood diy and the clone with two switches on and I have found they do not like switch mode psus.  both have encoders fitted, both work fine on battery but play up on psus. What i have found is that it is better to run them on battery when programming them as both have fallen over after being programmed on psus even though they verified without error YMMV

bill

i power them through the programmer cable.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on April 05, 2016, 10:24:31 pm
Two things...

Hope this helps. They are great little devices and incredibly functional and accurate considering their cost. The author has done a magnificent job of squeezing the most out of a little 8 bit processor.

Graham


I am very familiar with switch mode regulators.  The output of my step-up 5v regulator has less than 50mv p.p switching noise and I even bypassed the 5v right on the encoder. 


I would like to hear from other people that have or added the rotary encoder and don't exhibit this problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on April 05, 2016, 10:41:55 pm
If the pins are loaded down on output then the display would be affected.

Incorrect resistors could increase or decrease current flow when the pins are reading the encoder and may be causing a drop in VCC but since the encoder works OK at slow speeds, I think a wiring issue on the encoder PCB is not so likely.
On the other hand, I would certainly try a different encoder (only - no PCB) and test it before going about the changes to code that you are suggesting/trying.
The Fast_Rotation is almost necessary as it is the only way to escape from the automatic continuous test mode of capacitors and resistors on TP1-TP3 and from the Voltage measuring mode.

Graham

if your resistors are wrong, you could overload the pd1/3 pins when they are outputs.
that could drag the voltage down in the mcu and glitch it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 06, 2016, 12:53:32 am
@GBowes, thanks for your response.  Well, I am making some progress but still don't have a good solution.  The key to the problem is, I found out by accident that problem is NOT that the processor or the software are locking up but the display controller is latching up, disabling the display and at the same time the software jumps to the menu selection.  Once you are in the menu selection, the only way to exit it is to select the "Switch off" but since the display is blank, I was stuck.  If you keep clicking the switch, eventually you will hit the "Switch off" position and that is how I found out that the processor and the software was actually still running.

Looking at my display, I found out that the display controller is designed for 3.3v and they simply drop the Vcc with two series diodes.  Now I am not surprise that I am having this problem.  I believe everyone else that is using this tester, this display controller and this encoder will experience this problem.   And yes, I disabled the internal pull-ups on the processor (CFLAGS += -DPULLUP_DISABLE).

I was convinced that if I power the encoder from 3.3v that it will solve the problem but the improvement was minimal.  I also tried a second encoder I had (the same manufacturer) and I got basically the same results.  It looks like there is another manufacturer for these encoders, I might give it a try.  Maybe someone else has a better idea.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on April 06, 2016, 02:03:08 am
I doubt another encoder will be different. They are just make or break switches.

I was going to mention your diodes in an earlier thread as I considered them far more important than your concern about the NPN versus MOSFET but didn't want to get embroiled in a battle over definitions.
Those diodes on paper would drop 5.0V to about 3.4 - 3.6 which would probably be OK for the display. I have one of those units (the only one to which I did not add any hardware extensions) and the voltage to the display is closer to 4.1V so I expect the display to die an early death. The diodes drop very little voltage at the current levels of the LCD. Disabling the pullups helps mitigate the potential damage to the signal lines but still is far from ideal solution and I believe that you also need to add a pullup resistor to PD0. On another unit I had (which came with a 3.3V regulator on the LCD board), I added an HC4050 to translate the 5.0/3.3 v signal levels.

To your current problem... I cannot think of a good solution. I know that the author does not recommend this model due to the difficulty accessing some of the connections of the display interface. He has tested one of these and may have some suggestions that might help you get the encoder working properly.

Graham



Looking at my display, I found out that the controller is designed for 3.3v and they simply drop the Vcc with two series diodes.  Now I am not surprise that I am having this problem.  I believe everyone else that is using this tester, this display controller and this encoder will experience this problem.   And yes, I disabled the internal pull-ups on the processor (CFLAGS += -DPULLUP_DISABLE).

I was convinced that if I power the encoder from 3.3v that it will solve the problem but the improvement was minimal.  I also tried a second encoder I had (the same manufacturer) and I got basically the same results.  It looks like there is another manufacturer for these encoders, I might give it a try.  Maybe someone else has a better idea.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 06, 2016, 02:40:54 am
The only reason I am considering trying a different encoder manufacture is that I was really surprised that powering the encoder with 3.3v didn't solve the problem.  I would really like to hear from anyone that has this particular tester with the rotary encoder working without any problems. 

As far as powering the LCD, I might add another diode in series with the 2 existing.  Better yet I think I still have some of these 3 junction diodes in a DO41 package I used many years ago which I believe are obsolete now. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 06, 2016, 06:47:33 am
i still think the problem is related to the resistors, maybe not what they have printed on them.
they should limit the current to a point that wont effect the display.

they should be on vcc btw, not 3.3v - they are interacting wih the 5v device.
you dont want them bleeding low current 5v back to your 3.3v source.

as for the display, i would replace the diodes with a 3.3v LDO powered from the 5v rail.
something like a 1117

the display inputs are supposed to be 5v tolerant on the datasheet i had someplace.

btw, thanks for bringing my attention to the fast-rotation menu entry/exit function - i didnt know about that.
i am now removnig it from the menu in my build.  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on April 06, 2016, 09:39:49 am
Are the plans for a new schematic? I'll try to do it in KiCad, plus the PCB. I won't promise about being good enough, it will be my first try on KiCad and I didn't do one in tons of months.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 06, 2016, 11:40:56 am
Those diodes on paper would drop 5.0V to about 3.4 - 3.6 which would probably be OK for the display. I have one of those units (the only one to which I did not add any hardware extensions) and the voltage to the display is closer to 4.1V so I expect the display to die an early death. The diodes drop very little voltage at the current levels of the LCD. Disabling the pullups helps mitigate the potential damage to the signal lines but still is far from ideal solution and I believe that you also need to add a pullup resistor to PD0. On another unit I had (which came with a 3.3V regulator on the LCD board), I added an HC4050 to translate the 5.0/3.3 v signal levels.

The internal pullup resistors should be disabled anyway. The control/signal lines for the display are set up at startup as output (high or low, based on the defaults required). Since the rotary encoder is is parallel with two display signals, the firmware changes the two I/O pins from output mode to input mode for polling the encoder and after that back to output again. The high level for the display signal lines is 5V!

Yes, using a 3.3V LDO and a level shifter, like the 74HC4050, is the best way to connect a 3.3V display. Some displays may have 5V tolerant inputs, but series resistors (2.7k) for limiting the current might be a good advice. I've added level shifters to all the 3.3V graphic displays I use and I haven't seen any problems with a rotary encoder in parallel so far.

When the display is screwed up by the rotary encoder in parallel, one could try to add some sort of level shifting for the two display signal lines involved.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 06, 2016, 12:17:16 pm
Are the plans for a new schematic? I'll try to do it in KiCad, plus the PCB. I won't promise about being good enough, it will be my first try on KiCad and I didn't do one in tons of months.

I've started with a schematic for the ATmega 644/1284 based version. But it's going to be more like a dev-kit, i.e. it will be a modular design allowing to add different kinds of displays and hardware options. I think the main PCB will have the input protection, Zener test (30V boost converter), rotary encoder, 2.5V voltage reference, fixed self-adjustment cap, a switchable parallel cap for SamplingADC (new hw option) and a connector for additional modules (display, frequency counter, ...).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on April 06, 2016, 09:47:32 pm
Since I have written some PC software for the TT
- see German Site:
https://www.mikrocontroller.net/topic/248078?page=9  (https://www.mikrocontroller.net/topic/248078?page=9)
(search the veeeeeeeeeeeery long page for "Messtechniker") -
it would simplify matters if we could communicate via the serial
interface in both directions. i.e. RxD and TxD. Prefably SCPI style
or through a specific caommand set now that the ATmega 644/1284
provides much more memory compared to the "old" 328 the
memory of which is utilized to almost 100%.

Yours - Messtechniker
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 07, 2016, 09:12:48 am
it would simplify matters if we could communicate via the serial interface in both directions.

+1  :-+
Kudos for your software!! And thank you for sharing it.
I tested it few weeks ago when you posted it on the german forum.
The only thing I wish to have on this kind of tools is to be multi-platform

I made a really simple one with processing only to use it on win and mac.
To keep the PC software stupid simple I modified the k firmware to add at the beginning of each sting sent to the serial port the number of the line and a terminator at the end of each sting.

How do you recognize the start/end of each sting/measure?
Have you implemented several conditions to distinguish the parts of the measurements?

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: gcardinal on April 07, 2016, 10:01:08 am
Thanks for this great project! Im looking for this SMD breakout - or maybe source files for it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 07, 2016, 10:44:51 am
Hi Marcus,
   I loaded the new 1.22m firmware and I'm very happy with it. Thank you!!
I kept all the optocouplers used for the previous CTR manual measurement in the same order and this is the results with the 1.22m firmware.


Model     If                     Ic                     CTR                   hFE M12864       CTR M12864
                                                                                       k firmware 656    m firmware 1.22m
PC123   0.005702985   0.006419403   112.5621565   0.92                    167
PC123   0.005704478   0.005997015   105.1282051   0.69                    118
PC123   0.005702985   0.006285075   110.2067522   0.78                    139
PC123   0.005702985   0.006316418   110.7563465   0.95                    169
PC123   0.005704478   0.006316418   110.7273679   0.83                    143
4N35    0.005704478   0.00571791     100.2354788   0.75                     132
4N35    0.005698507   0.005491045   96.35935045   0.68                     118
4N35    0.0057             0.005908955   103.6658811   0.83                     146
4N35    0.005704478   0.00569403     99.81684982   0.75                     131
4N35    0.005704478   0.005459701   95.70905285   0.65                     116
L817B   0.005689552   0.006843284   120.2780693   1.33                     234
L817B   0.005704478   0.006934328   121.559393     1.31                     224
L817B   0.005685075   0.007050746   124.022053     1.25                     208
L817B   0.005698507   0.006953731   122.0272394    1.25                    211
L817B   0.00568806     0.007010448    123.2484912   1.11                    173
4n33                                                                                                          1724
4n33                                                                                                          2261
4n33                                                                                                          1892
4n33                                                                                                          1463
4n33                                                                                                          1681
4n33                                                                                                          1806

The only issues (things I don't like but not actual bugs) I found so fare are:

1)
For the ESR measurement you selected the test poits 1 and 2 while on the k firmware are 1 and 3
My issue is that on the M12864 I can't use the banana plugs anymore to perform the measures, because this are connected to TP1 and TP3
My main use of the banana plugs are with the tweezers that are really useful

2)
I keep the TT inside my bag and I find it always on.
On the display I found "done!" or "No component found!" and it stay there forever.
Also turning the encoder to enter the menu, after I select Exit it appear "done!" but it stay there forever.
 
I replicated the issue pushing the encoder during a measure without components and instead of perform 5 measure and than power off it stops at "No component found!"

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 07, 2016, 10:49:42 am
it would simplify matters if we could communicate via the serial
interface in both directions. i.e. RxD and TxD. Prefably SCPI style
or through a specific caommand set now that the ATmega 644/1284
provides much more memory compared to the "old" 328 the
memory of which is utilized to almost 100%.

The ATmega664's PD1 (TXD0) is already assigned for serial output and PD0 (RXD0) is unused. You're not the only one with an idea about a bidirectional serial port (possibly a serial2usb adapter). So we could try to add some sort of command set for control and reading results later on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on April 07, 2016, 11:01:07 am
The only thing I wish to have on this kind of tools is to be multi-platform #

On platforms other than Windows you'd have to use an emulator like "Wine", for example.

I made a really simple one with processing only to use it on win and mac.
To keep the PC software stupid simple I modified the k firmware to add at the beginning of each sting sent to the serial port the number of the line and a terminator at the end of each sting.

Also throught about doing this. But decided instead inspite of the parsing difficultires
to stay compatible with the standard firmware. You might ask Kubi in the
German forum to include your fimware mod in the k firmware.
I would then adapt my progs accordingly.

How do you recognize the start/end of each sting/measure?

I simply select a suitable (unique) character in the string to split it for further
string processing. Certainly not ideal because I am forced to used different
splitting characters depending on the type of component.

Have you implemented several conditions to distinguish the parts of the measurements?

No. Is too diffucult or impossible when simply relying on what the Transistor Tester
currently spits out. Hence my request for duplex serial communication for the larger ATMEGAs.

Therefore wrote separate progs for each component. Currently these progs are
BJT, JFET, MOSFET, OPTO and RES. The prog CAP for capacitors being the last on my list
will be available soon. Still needs to simmer a bit. :)

Yours - Messtechniker

Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 07, 2016, 11:47:38 am
You might ask Kubi in the German forum to include your fimware mod in the k firmware.
I would then adapt my progs accordingly.

That will be great!!
Since I think others around the world have implemented something that use the actual serial output, my idea was to have an option on the makefile to select the different serial format standard/mauro/...

Is too diffucult or impossible when simply relying on what the Transistor Tester
currently spits out. Hence my request for duplex serial communication for the larger ATMEGAs.

Therefore wrote separate progs for each component. Currently these progs are
BJT, JFET, MOSFET, OPTO and RES. The prog CAP for capacitors being the last on my list
will be available soon. Still needs to simmer a bit. :)

We basically followed the same path arriving to different conclusions :)
My actual program visualize on a PC screen the same output of the TT but to perform evaluations on the measures a lot of parsing is needed and slowed me a bit

Well done  :-+
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 07, 2016, 11:58:09 am
I kept all the optocouplers used for the previous CTR manual measurement in the same order and this is the results with the 1.22m firmware.

Thanks for the measurements! I think I should add the output of I_f for a better understanding of the CTR value. Since the LED's cathode and the BJT's emitter are connected to one probe they share the voltage drop across the current shunt. If I_e increases the voltage drop increases too, and therefore I_f will decrease. Unfortunately the CTR is non-linear.

Quote
1)
For the ESR measurement you selected the test poits 1 and 2 while on the k firmware are 1 and 3
My issue is that on the M12864 I can't use the banana plugs anymore to perform the measures, because this are connected to TP1 and TP3
My main use of the banana plugs are with the tweezers that are really useful

That's an easy fix :) I'll change it to 1-3 to be compatible with the k-firmware.

Quote
2)
I keep the TT inside my bag and I find it always on.
On the display I found "done!" or "No component found!" and it stay there forever.
Also turning the encoder to enter the menu, after I select Exit it appear "done!" but it stay there forever.

Is there a blinking cursor at the bottom right of the display? To switch off the tester please press the button for 0.3s at least. It will show a "bye" and power off.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 07, 2016, 01:03:35 pm
Thanks for the measurements! I think I should add the output of I_f for a better understanding of the CTR value. Since the LED's cathode and the BJT's emitter are connected to one probe they share the voltage drop across the current shunt. If I_e increases the voltage drop increases too, and therefore I_f will decrease. Unfortunately the CTR is non-linear.

You are welcome, and thank you for the implementation of this function.
Can't wait to see a Chinese clone with the 644 for 17$ where we can have all the options enabled by default without any flash/processor limit  :popcorn:

Quote
Is there a blinking cursor at the bottom right of the display? To switch off the tester please press the button for 0.3s at least. It will show a "bye" and power off.

Yes, forgot to mention the ">" cursor on the right-low corner.
If it goes in this state it will never self power off.
The problem is that if it goes in this state in the bag it will drain the battery.
Is it possible to have an optional self power off after x minutes of inactivity?

I think I will just add a switch on the battery.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: kenabi on April 16, 2016, 06:08:57 pm
so i snagged one of the black case fish8840 models ( http://www.ebay.com/itm/131539364479 (http://www.ebay.com/itm/131539364479) ) and it j ust gives me the blank screen of doom. tossed a resistor in there, still blank screen. anyone have a way to fix this? not seeing much in the thread about this model.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 16, 2016, 06:31:39 pm
If it's dead on arrival ask the seller for a refund. If the LED is lit after powering on it might be the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kenabi on April 16, 2016, 06:38:59 pm
lcd lights up, it just doesn't show any text. powers off after x seconds. any way to test?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 16, 2016, 06:43:25 pm
Bad contrast setting? You could check it with a compatible display, a DSO or Logic Analyzer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kenabi on April 16, 2016, 06:54:11 pm
don't have a display, only got one of those cheap diy dso kits, and no LA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stryker on April 16, 2016, 09:28:42 pm
Thanks for this great project! Im looking for this SMD breakout - or maybe source files for it?
Actually I'd go for one of those too - and put mine in an enclosure.  Can anyone recommend a SMT breakout other than this if they're using one, and where did you find it? 

Thanks
Title: $20 LCR ESR Transistor checker project
Post by: timb on April 16, 2016, 09:40:24 pm
Hey guys, just grabbed one of these MK-328 units on eBay to replace my trusty MK-128 (which has worked flawlessly for over a year now, but I really wanted a graphic LCD). Does anyone know what branch/compile options I should use for this unit? (I'm wondering about its particular display, etc.)

I haven't been following development, so I'm not sure what's changed. I'm trying to read back through the thread but it's a lot of pages. :)

http://www.ebay.com/itm/321936118996
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 16, 2016, 10:18:44 pm
With so many variations, it may be prudent to check inside and verify the display controller that's in your particular embodiment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kenabi on April 16, 2016, 11:01:10 pm
uses a Lx-12864TS spi lcd module, no visible chips on it, 12 contact flex cable, can't even find who makes it. from left (when staring at side of board the avr is soldered to) contact 1 and 6 are ground, contact 2 is +5v when tester is 'on', board trace is marked 3v3. riiight.
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on April 17, 2016, 01:08:31 pm
@timb

I think you can use the Makefile given at https://yadi.sk/d/yW8xa5NJgUo5z/Mk-328/Firmware  to get yourself started.

Best regards.



Title: Re: $20 LCR ESR Transistor checker project
Post by: Melkocha on April 20, 2016, 11:01:03 pm
Hi folks!
I have built a model T4 and it is costing me too much to make it work.
The problem is the following:
I turn it on and, after of first screen -without connecting anything- and after 18 seconds appears on display:
"Cell!" and, below: 1. 08V   0mV  1. 43V,  then began the routine of testing T1, T2, etc.
It the same if I connect any component to any TP.
If I put a LED does not see it is flashing and does so only when the message "short Probes!" appear.
I tried several firmwares, particularly from mid last year.
I have checked the circuit and it seems to be correct.
Can be the value of CAP EMPTY LEVEL?
Anyone have any suggestions?
Thanks in advance!
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on April 21, 2016, 06:34:30 am
Probably damaged input ports of the MCU (result of measurement the charged capacitor).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Melkocha on April 21, 2016, 01:17:39 pm
Probably damaged input ports of the MCU (result of measurement the charged capacitor).
Thanks Tom, but I made sure not generate this problem and, however, I changed the chip: The result was exactly the same.
In these tests, very sporadically, the tester seems to work and appears the legend of "no component...", and in others, the values of the second line change: 0 mV appears in third place, etc.

1) Any other suggestions?
2) What mean 3 values ??in the second line below "Cell!"?
Thank you again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 21, 2016, 01:28:44 pm
Do you mind to post some picture of your assembled tester?
In case someone can spot something wrong
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: bingo600 on April 21, 2016, 02:01:37 pm
I just got this one
http://www.ebay.de/itm/152011732946 (http://www.ebay.de/itm/152011732946)

Does anyone have a pointer to the firmware that fits this one (source + makefile)

TIA

/Bingo
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrjoda on April 21, 2016, 04:09:48 pm
i bought T4, it works somehow, so... i made bad decision(after hour) :D i flash it with new firmware and... suprise ! it does not work again !  of course, it works but it measure totaly bullshits, i try all released versions of FW, fuse as recommended (f7,d9,fc (04 gives me verification error)). Calibration shows some number, it pass when ask me to connect cap i connect it, measure exact value and after that, when calibration is complete, measurement wont work, it missdetect almost everythink as capacitor, at random pins with thousands of uF and F... For example, when i connect 100nF cap between 1 and 2, its shows capacitor between 3 a and 2 and capacity 3654uF BUT if i reconnect cap when this shit is turn on to 3 and 2, it measure correct value. When i press buton, again missdetect.

 With original firmware was values pretty close to reality :)


any suggestion ?

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 21, 2016, 04:52:33 pm
Have you also updated the EEPROM?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrjoda on April 21, 2016, 07:17:42 pm
yes, HEX + EEPROM + fuses,
classic tools USBASP + AVR Extreme Burner
Title: Re: $20 LCR ESR Transistor checker project
Post by: Melkocha on April 21, 2016, 09:56:24 pm
Hi folks!
I have built a model T4 and it is costing me too much to make it work.
The problem is the following:
I turn it on and, after of first screen -without connecting anything- and after 18 seconds appears on display:
"Cell!" and, below: 1. 08V   0mV  1. 43V,  then began the routine of testing T1, T2, etc.
It the same if I connect any component to any TP.
If I put a LED does not see it is flashing and does so only when the message "short Probes!" appear.
I tried several firmwares, particularly from mid last year.
I have checked the circuit and it seems to be correct.
Can be the value of CAP EMPTY LEVEL?
Anyone have any suggestions?
"Probably damaged input ports of the MCU (result of measurement the charged capacitor)."
Thanks Tom, but I made sure not generate this problem and, however, I changed the chip: The result was exactly the same.
In these tests, very sporadically, the tester seems to work and appears the legend of "no component...", and in others, the values of the second line change: 0 mV appears in third place, etc.

1) Any other suggestions?
2) What mean 3 values in the second line below "Cell!"?

Another clue:
The values of Ri_Lo = Ri_Hi = .0 Ohms

What do you think?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 22, 2016, 09:20:03 am
yes, HEX + EEPROM + fuses,
classic tools USBASP + AVR Extreme Burner

Do you power your tester with a battery or a PSU (linear or switching mode)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrjoda on April 22, 2016, 08:46:26 pm
i tried both, 9V battery with 8,5V and linear PSU set to 9,5V. Nothing change. When i get my camera back i will shoot a video. I will capture process of calibration and i try measure something. I checked all resistors and values are correct (measured with fluke 187). Reference is 2,4953V stable,  supply 4,9863V stable.

I will put here a calibration numbers later.



is there any repository with original software from china ? i rushed and i did not read values before replacing firmware  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: TJM on April 23, 2016, 08:18:06 am
A month ago I bought MK-328 from ebay, since then I used it a lot to test hundreds of new "old stock" transistors. One day the battery died, it was already late and I did not have replacement, so I used an old 9V NiMH rechargeable battery, which worked fine for a while, then suddenly the display faded and the tester switched off. The next day I put in a fresh 9V battery and noticed two things: the unit lost  its calibration - but I did it following the on screen procedures and everything went back to normal except a second thing - i think it had LCD contrast settings stored somewhere in memory, at the moment I have to look at it with an angle because the screen is dark.
Does anyone know how to fix it ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on April 23, 2016, 12:32:52 pm
I wander if its a low volatage issue ?
I leave mine in a box with the battery disconnected and have no issues .
So maybe keeping track of batteries voltage and not using if below ? what ever ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 23, 2016, 12:45:53 pm
Enter the menu and adjust the contrast. From the documentation (k-firmware):

Quote
Contrast This function is available for display controllers, which can adjust the contrast level with
software. The value can be decreased by a very short key press or left turn with the rotary
encoder. A longer key press (>0.4s) or a right turn of the rotary encoder will increase the value.
The function will be finished and the selected value will be saved nonvolatile in the EEprom
memory by a very long key press (>1.3s).
Title: Re: $20 LCR ESR Transistor checker project
Post by: richfiles on April 25, 2016, 06:52:57 am
Has anyone tried this (assumed to be) recent Chinese revision? They are calling it a 2016 EZM328 (GM328R) transistor tester.
http://www.ebay.com/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/272165236396 (http://www.ebay.com/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/272165236396)

It costs a little bit more, but the unit has a socketed DIP ATmega328, A rotary encoder/test button, graphic display, headers for frequency and flying test leads, the standard ZIF socket we've seen on most of these units, and claims to have a precision reference source. The listing says it's using "the 2016 version of the latest V1.12K software".

Has anyone purchased one of these units yet, and if so, does it really have an actual voltage reference, or just a zener? Is it worth the few bucks premium over other testers? I do like the fact that it uses through hole components (good for modding), and the new screen configuration makes it no bigger than many of the SMD versions. How hard is modding these Chinese units to support things like the input protection feature I've seen elsewhere on this thread?

I'm strongly considering purchasing one.


I'm still skimming things (81 pages is a LOT :o), but I'm genuinely curious if anyone has come up with a PC board that unifies all the options that are possible. Input protections, higher zener testing, support for ATmega 644 or 1284, etc? I saw a unit with built in protection quite a few pages back, but it used the text LCD, and I just like the graphic LCD too much!

These devices remind me of a more advanced version of the transistor tester on my old DMM. It was a Radio Shack 22-174 and it had a three terminal transistor tester that did not require you to know the part or pinout, You just inserted the part any way, pressed the test button, and it told you if it was PNP or NPN, told you the pin configuration, and gave an hfe measurement. Obviously, not as advanced as this unit, as it only did those two types of transistors, but this was also made way back in the 1990s.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 25, 2016, 11:08:48 am
Has anyone tried this (assumed to be) recent Chinese revision? They are calling it a 2016 EZM328 (GM328R) transistor tester.
http://www.ebay.com/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/272165236396 (http://www.ebay.com/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/272165236396)

Looks like a nice clone, but the ISP header is missing, as usual. I think it would be more easy to add the relay based protection than the SRV05-4 (SMD). Since the clone got a 2.5V reference you just need a resistor, NPN, a tiny relay (e.g. Fujitsu FTR-B3 4.5V), freewheeling diode and some wire.

Quote
I'm still skimming things (81 pages is a LOT :o), but I'm genuinely curious if anyone has come up with a PC board that unifies all the options that are possible. Input protections, higher zener testing, support for ATmega 644 or 1284, etc? I saw a unit with built in protection quite a few pages back, but it used the text LCD, and I just like the graphic LCD too much!

There's no such board yet. I'm working on a modular dev board with ATmega644 and most (all?) options. If someone likes to help, it should be simple to fork a graphic LCD board and a character LCD board for users. Seems I should move from Eagle Freeware to Kicad to overcome the board size limits.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jleg on April 25, 2016, 02:12:17 pm
Has anyone tried this (assumed to be) recent Chinese revision? They are calling it a 2016 EZM328 (GM328R) transistor tester.
http://www.ebay.com/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/272165236396 (http://www.ebay.com/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/272165236396)

It costs a little bit more, but the unit has a socketed DIP ATmega328, A rotary encoder/test button, graphic display, headers for frequency and flying test leads, the standard ZIF socket we've seen on most of these units, and claims to have a precision reference source. The listing says it's using "the 2016 version of the latest V1.12K software".

if you don't mind a bit of soldering, i'd go for this one:
http://www.ebay.com/itm/M328-LCD-12864-DIY-Transistor-Tester-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/161913228003?hash=item25b2c7cae3:g:pvwAAOSwf-VWZ~zL (http://www.ebay.com/itm/M328-LCD-12864-DIY-Transistor-Tester-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/161913228003?hash=item25b2c7cae3:g:pvwAAOSwf-VWZ~zL)

This one does have a VRef, and 0.1% Rs - and flashing latest firmware is also possible, if you have some socket with ISP headers for the Atmega...
Title: Re: $20 LCR ESR Transistor checker project
Post by: richfiles on April 25, 2016, 11:04:11 pm
I got no problem with soldering, but man do i hate inverted LCDs!  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: macboy on April 26, 2016, 03:24:23 pm
Has anyone tried this (assumed to be) recent Chinese revision? They are calling it a 2016 EZM328 (GM328R) transistor tester.
http://www.ebay.com/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/272165236396 (http://www.ebay.com/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/272165236396)

It costs a little bit more, but the unit has a socketed DIP ATmega328, A rotary encoder/test button, graphic display, headers for frequency and flying test leads, the standard ZIF socket we've seen on most of these units, and claims to have a precision reference source. The listing says it's using "the 2016 version of the latest V1.12K software".

if you don't mind a bit of soldering, i'd go for this one:
http://www.ebay.com/itm/M328-LCD-12864-DIY-Transistor-Tester-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/161913228003?hash=item25b2c7cae3:g:pvwAAOSwf-VWZ~zL (http://www.ebay.com/itm/M328-LCD-12864-DIY-Transistor-Tester-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-/161913228003?hash=item25b2c7cae3:g:pvwAAOSwf-VWZ~zL)

This one does have a VRef, and 0.1% Rs - and flashing latest firmware is also possible, if you have some socket with ISP headers for the Atmega...
I bought that kit from a different seller (http://www.ebay.com/itm/321944016234) and finally assembled it last night. Worked on the first go. This is an excellent value, and is fully featured: graphic LCD, rotary encoder, ZIF testing socket, socketed DIP ATMega328 chip (easy to re-program or replace), TL431 VREF, etc.  The PCB is high quality, with good sized component holes (not too tight or loose) and pads, nice red soldermask, and with all component valued silkscreened on - I didn't use any reference other than the silkscreen to fully assemble the kit.  I didn't mind the work of soldering it together, that was half the reason I bought it, just to spend some quality time with my soldering iron.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on April 29, 2016, 06:27:08 pm
it would be nice if they included a programming header - or atleast the pads for it!
you dont want to have to pull the chip every time there is a software update.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on April 30, 2016, 12:46:21 am
Sometimes it is handy to have a few processors around labeled with the different firmware versions, in that case you can go back to the one it was working right :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 30, 2016, 06:38:51 pm
These devices remind me of a more advanced version of the transistor tester on my old DMM. It was a Radio Shack 22-174 and it had a three terminal transistor tester that did not require you to know the part or pinout, You just inserted the part any way, pressed the test button, and it told you if it was PNP or NPN, told you the pin configuration, and gave an hfe measurement. Obviously, not as advanced as this unit, as it only did those two types of transistors, but this was also made way back in the 1990s.

I still like it better than any other DMM despite it being the most inaccurate (even the "free" [not-so-free after shipping and taxes] Harbor Freight meter is a lot more accurate). Couldn't find another DMM with automatic pinout detection. Attaching a picture of it measuring a 2N2222 so people would see what we're talking about. The problem is that it doesn't always properly identity leads, which causes it to show the wrong type and HFE. This is what initially prompted me to look for an alternative, and how I found the device that this thread is about.


I'm curious, with the same hardware available in a case, why do so many people insist on buying it without the case? The price difference is usually not that great.
Title: Re: $20 LCR ESR Transistor checker project
Post by: richfiles on May 01, 2016, 12:10:39 am
Shame Radio Shack hasn't sold that model for years, nor came up with an updated model, nor continued to be a viable hobbyist business...

I hate that I popped mine.  :'( :-BROKE
I was measuring current through some LED strips and it got really late... I immediately knew I screwed up when I did it... I was tired, and had the wires & knob in the wrong places.

One of (among many) of the problems with that meter, is it only does NPN and PNP type transistors. Doesn't handle FET of any kind. These Atmel based testers are a next generation of test versatility. Given the low cost of these component testers, I'm genuinely surprised no company has tried to do the automatic component identifier/tester as a next gen meter selling gimmick. Personally, I WOULD buy a cheap crappy DMM just to have a proper ASIC based tester around for that and nothing else. Besides, if one of those testers got packed into a multimeter, Dave would have to shit on it for being a multimeter with a transistor tester!  ;) :-DD

 As to why people buy the bare boards vs the case? I dunno. I looked at the cases, and I honestly did not like a single one's configuration. I literally thought "I could do better, and it probably won't feel like cheap and plasticky Chinese crap" With a home brew case, you also have room to add on extras, like input protection, rechargeable batteries, etc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirKnowsALot on May 03, 2016, 01:43:13 pm
I know I'm late to the party (typical for me), but I've read every post on this thread to get caught up.  This is an amazing community of very helpful people such as Markus, Tomas, and many others.

I bought this tester eBay auction: #http://www.ebay.com/itm/221961865013 and found it does a poor job at capacitance/inductance measurement, which is what brought me to this forum.  Based on what I read, I believe this to be a LCR-T4 12864LCD unit with unversioned Chinese firmware, although it does not match precisely any tester photo I've seen on this thread.  I hope to reflash with M- or K-firmware and solve my issues, and I think mega328_st7565_kit is the right branch, correct?

I've attached a photo of the back which shows the ISP connector I added.  One notable difference I found was that on my unit, the ISP arrangement was CORRECT.  I just plugged my USBISP with 10-to-6-pin adapter straight into my header and was able to pull the EEPROM, code, and fuse info from it.  At least I think.  I've included it here also, as it may help someone.  (Note MTester.bin->MTester.hex and MTester.eep->EEPROM.hex to make forum happy). edit: I guess I converted the code from Intel hex to binary at some point

If I rebuild code, how do I know that I have the build flags properly set?  Although this looks like a standard design, can I irreversibly damage it with improper options selected?  Could I reflash with my code+eeprom data to get back to where I started?  I thought I read somewhere that code pulled from the tester is not usable due to locking.  Since I did get something, would it not be valid?

Since I'm willing to forego the new, cool functions (rotary, func-gen, etc.), I hope this can be a smooth experience. 

Please forgive any newbie mistakes I've made.  Any of your expert advice is welcome.   :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 03, 2016, 05:31:38 pm
I bought this tester eBay auction: #http://www.ebay.com/itm/221961865013 and found it does a poor job at capacitance/inductance measurement, which is what brought me to this forum.  Based on what I read, I believe this to be a LCR-T4 12864LCD unit with unversioned Chinese firmware, although it does not match precisely any tester photo I've seen on this thread.  I hope to reflash with M- or K-firmware and solve my issues, and I think mega328_st7565_kit is the right branch, correct?

Seems to be a slightly modified PCB of the T4 clone. For the k-firmware the best bet would be mega328_T3_T4_st7565 and for the m-firmware there's a display profile in the config.h file. The firmware you've downloaded from the clone looks fine. It got a lot of known strings ;) So I'd guess, you could re-flash it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rescator on May 03, 2016, 06:13:02 pm
Hello,

I bought this tester Aliexpress :

http://fr.aliexpress.com/item/Hot-ESR-T4-Mega328-Digital-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-LCR/32579382733.html. (http://fr.aliexpress.com/item/Hot-ESR-T4-Mega328-Digital-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-LCR/32579382733.html.)

I am very disappointed because it does not recognize field effect transistors (tested: 2N3819 and MPF102) These are seen as bipolar NPN with a very high gain (between 100 000 and 510 000!)

The low value inductors (2.2 nH) appear as resistors (maybe normal ?)

Do you have the same phenomena ?

What can I do ? change firmware ?

thanks for your advices

Gerard
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 03, 2016, 09:13:02 pm
I am very disappointed because it does not recognize field effect transistors (tested: 2N3819 and MPF102) These are seen as bipolar NPN with a very high gain (between 100 000 and 510 000!)

The low value inductors (2.2 nH) appear as resistors (maybe normal ?)

A 2N3819 shouldn't be any problem, but the standard inductance measurement starts at about 10µH. Unfortunately that clone runs a modified firmware, so I can't say anything about it. You could try the firmware mentioned in the post above.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on May 04, 2016, 12:22:43 am
The low value inductors (2.2 nH) appear as resistors (maybe normal ?)
2.2nH has an impedance of 0.000014 ohms at 1kHz. Yes I think not recognizing it as an inductor is very normal.

A 25mm wire loop (single turn) has a 10nH inductance. Every time you test anything, you make a loop. If it could see inductances that low, it would be seeing every resistor as an inductor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 04, 2016, 01:14:02 am
[...]
I am very disappointed because it does not recognize field effect transistors (tested: 2N3819 and MPF102) These are seen as bipolar NPN with a very high gain (between 100 000 and 510 000!)

The low value inductors (2.2 nH) appear as resistors (maybe normal ?)

Do you have the same phenomena ?

What can I do ? change firmware ?

thanks for your advices

Gerard

Nobody knows exactly what's in the Chinese firmware (other than the the people who actually release it, and they don't seem to be too fond of sharing). For this reason alone I think it is a good idea to reflash with an "official" firmware.

Older firmware versions detected all inductors as resistors. Even older firmware could not read inductance value, either. This is normal. Flashing with a newer version should fix it.

You may want to try to read in and make a copy of the firmware that the tester came with first (not always possible, but worth a try). It's always good to have a copy.


[...]
If I rebuild code, how do I know that I have the build flags properly set?  Although this looks like a standard design, can I irreversibly damage it with improper options selected?  Could I reflash with my code+eeprom data to get back to where I started?  I thought I read somewhere that code pulled from the tester is not usable due to locking.  Since I did get something, would it not be valid?
[...]

Read the manual. It includes build options. Try to change what makes sense changing for your particular tester based on the description of the things that can be changed. If something doesn't work as desired, undo, rebuild, reflash.

The code you read should be valid. The problem with locking is actually being able to read it.

It would be difficult to do any damage just by flashing, but make sure your fuses don't deny SPI access and don't remap the RST pin. It is also not impossible to exceed the number of times you can write to the programmable memory, but that should not be a problem in most cases. Reflashing these devices is a pretty safe operation overall.


A 25mm wire loop (single turn) has a 10nH inductance.

It does?
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on May 04, 2016, 02:31:21 am
A 25mm wire loop (single turn) has a 10nH inductance.

It does?
Yes. To get a 2.2nH inductance, that is a single turn with a 10mm diameter. Basically at that level, all wiring looks like an inductor. It is all way below the possible range of the $20 LCR circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rescator on May 05, 2016, 09:02:29 am
Hello, thank you for all your answers.

I also have a big doubt on the firmware version installed.
When starting the tester, the version is not specified on the splash screen.

I do not know what firmware and which version to choose to replace

I study the problem before any change !

Gerard
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 05, 2016, 10:56:32 am
BTW, the optional Sampling ADC method in the current k-firmware is able to measure down to about 300nH (8MHz crystal). With a 16 MHz crystal you could push the limit further.
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirKnowsALot on May 05, 2016, 08:34:03 pm
Seems to be a slightly modified PCB of the T4 clone. For the k-firmware the best bet would be mega328_T3_T4_st7565 and for the m-firmware there's a display profile in the config.h file. The firmware you've downloaded from the clone looks fine. It got a lot of known strings ;) So I'd guess, you could re-flash it.
I tried reflashing with 1.12k_r453 prebuilt by Tomas (https://www.mikrocontroller.net/topic/248078?goto=4120737#4105488 (https://www.mikrocontroller.net/topic/248078?goto=4120737#4105488)) which turned the backlight on but nothing more.  I was able to flash the code I originally extracted back and at least it works again.  When I get some more time I will look more closely at the makefile and build my own version.  It is good to know that if you can get the original code out of the tester you can use it for disaster recovery.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on May 05, 2016, 11:22:09 pm
Quote from: SirKnowsALot
I tried reflashing with 1.12k_r453 prebuilt by Tomas (https://www.mikrocontroller.net/topic/248078?goto=4120737#4105488 (https://www.mikrocontroller.net/topic/248078?goto=4120737#4105488)) which turned the backlight on but nothing more.  I was able to flash the code I originally extracted back and at least it works again.

display contrast is a mess in the makefiles,

try changing the makefile to read
Quote
CFLAGS += -DVOLUME_VALUE=50

that's the optimal setting for the GM328A tester, and it uses the same display as the T4

Title: Re: $20 LCR ESR Transistor checker project
Post by: enut11 on May 06, 2016, 10:26:28 am
Hi All. I have a similar device that has proven to be very useful and well as accurate. I powered mine from 2 cell LiPo pack as it draws about 30mA when testing.
Unfortunately, I was testing some caps for a project when I zapped it with a 25v electro that had been sitting in the drawer for weeks, fully charged. Now my tester keeps rebooting. So sad.
I found it so useful that I ordered another one from HK at just under $20AU.
http://www.ebay.com.au/itm/322055635297?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com.au/itm/322055635297?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
enut11
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 06, 2016, 07:06:08 pm
I like EZM's versions. U3 there may be able to protect the device next time you do that. But the old device may still be salvageable if you can replace the MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JacquesBBB on May 06, 2016, 09:02:05 pm
In mine, I put the MCU on a zif socket. This is more easy to change the firmware, and was very useful to just  change the MCU in 10 seconds when I zapped mine.
https://www.eevblog.com/forum/beginners/how-to-blow-a-esr-meter/msg679338/#msg679338 (https://www.eevblog.com/forum/beginners/how-to-blow-a-esr-meter/msg679338/#msg679338)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on May 06, 2016, 09:10:49 pm
That's a nifty idea for frequently taking the mcu in/out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JacquesBBB on May 07, 2016, 02:09:00 am
I did that because at the begining i had to make modifs of the code for this model to have the proper display. The zif socket just fitted.
Title: Re: $20 LCR ESR Transistor checker project
Post by: morbid80 on May 08, 2016, 02:21:29 am
I tried reflashing with 1.12k_r453 prebuilt by Tomas (https://www.mikrocontroller.net/topic/248078?goto=4120737#4105488 (https://www.mikrocontroller.net/topic/248078?goto=4120737#4105488)) which turned the backlight on but nothing more.  I was able to flash the code I originally extracted back and at least it works again.  When I get some more time I will look more closely at the makefile and build my own version.  It is good to know that if you can get the original code out of the tester you can use it for disaster recovery.

i got a similar tester like yours.lcr-T3. if u manage to build a working firmware for this model, do share it with us. still waiting for my programmer from aliexpress
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirKnowsALot on May 08, 2016, 12:29:00 pm
Will do.  I rebuilt code from mega328_T3_T4_st7565 which resulted in the same issue, and I tried to build m-firmware (I'm not sure I did it correctly, but it compiled) and I still got the backlight-only result. 

I thought I would next trace out the circuit to see if it deviates from the standard design somehow.

I extend the challenge and invitation to anyone with this same tester (http://www.ebay.com/itm/221961865013 (http://www.ebay.com/itm/221961865013)) to share any experience.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 08, 2016, 12:59:36 pm
Is the display of your tester ST7565 compatible? Maybe it got some other controller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rescator on May 08, 2016, 02:15:04 pm
Hello,

@SirKnowsAlot
I think I have the same tester.
I do not know which version of firmware. The splashscreen does not indicate the version number. (view the photo)
The operation is about right, except for the test with J-FET (tested: 2N3819 and MPF 102)

I think the only solution is to change the firmware, but I do not know which to choose.
I read in detail www.mikrocontroller.net (http://www.mikrocontroller.net) about the transistortester, but it's not clear to me  :scared:

I think I'll just change tester model !  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirKnowsALot on May 08, 2016, 09:58:11 pm
Yes that is my exact tester.
I'm afraid that my interest in this tester has just disappeared--I was attempting to reflash and Windows' command line retrieval screwed me over.  I think my efuse data was scrambled and now my tester will not respond to avrdude.
This was the tail-end of the command that was sent:
Code: [Select]
... -U lfuse:w:0x04:m -U hfuse:w:0xD9:m -U efuse:w:0x04:mD9:m -U efuse:w:0x04:m

avrdude responded with:
Code: [Select]
avrdude: reading input file "0x04:mD9"
avrdude: invalid byte value (0x04:mD9) specified for immediate mode
avrdude: write to file '0x04:mD9' failed
avrdude: safemode: Fuses OK

I think that the first efuse parameter must have ruined my AVR.  I was using the command retrieval in order to eliminate entering the long command string and didn't notice the corrupted parameter. |O

I hoped that I could just go back and reprogram the fuses, but the device will not respond to avrdude at all.  Even with -F option.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on May 09, 2016, 01:05:18 am
What on earth is "mD9" ? I suggest you double check your command line...

e.g.

... -U lfuse:w:0x04:m -U hfuse:w:0xD9:m -U efuse:w:0x04:mD9:m -U efuse:w:0x04:m
Title: Re: $20 LCR ESR Transistor checker project
Post by: onlooker on May 09, 2016, 01:08:15 am
Fuse messing up happened to me too. I just bought a new atmega328p (about $1) to replace it. To prepare for more mess ups, one can also buy an AVR high voltage parallel programmer that can reprogram/correct fuses for about $17.   
Title: Re: $20 LCR ESR Transistor checker project
Post by: kenabi on May 09, 2016, 03:48:10 am
on my fish8840 (the one with the case) whats the pin that outputs the contrast signal? trying to track this down from the lcd in isn't working, as frankly nothing seems to do anything beyond shutting the thing off when i try to apply a pot between any pins and ground. if i can figure out which one is actually the contrast pin from the avr and trace outwards maybe i can get somewhere.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 09, 2016, 09:49:51 am
The contrast of a graphic LCD is set by a command usually, and not via a dedicated pin like V0 for HD44780 compatible displays. k and m-firmware allow to change the contrast for graphic LCDs via the main menu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirKnowsALot on May 09, 2016, 11:44:43 am
What on earth is "mD9" ? I suggest you double check your command line...
As I indicated in my post, I was using the command-line retrieval in the DOS box and it added the extra characters.  Because I wasn't paying close attention to what I was doing, I sent the command without correcting it.

The moral here is to be very careful when programming your AVR.
Title: Re: $20 LCR ESR Transistor checker project
Post by: richfiles on May 15, 2016, 03:29:55 am
You know, a fun component to measure is a piezo disc (it'll show up as a capacitor). You get to listen in on the test! ;D

Just got my tester yesterday. It's marked as an EZM328 V1.10. It has a really good looking graphic LCD, an encoder, SMT pads, and sockets for both tester and function gen. The best part is the through hole construction and socketed micro controller. Feels very hackable! Construction quality feels VERY good too! Only one little spot of flux was missed. the rest of the board is perfectly clean, and I see no bad solder joints.
Title: Re: $20 LCR ESR Transistor checker project
Post by: at2marty on May 15, 2016, 03:51:59 pm

I bought one of these (http://www.ebay.com/itm/141767800169) and put it together yesterday.  The firmware that shipped with it was shown as Version 1.12k.  However, I wanted to customize the firmware so I downloaded the latest release of the software, changed a couple of options in the Makefile in the Software/trunk/mega328_st7565_kit directory, compiled and uploaded to a spare Mega 328p that I had.  After spending some time playing with it, so far I'm impressed.  For just under $20 it seems to be a handy little device.

The following is the system that I used to build the firmware.

Linux Operating System
avr-gcc 4.8.1
avrdude 6.1

I programmed it using an stk500 programmer, though there are less expensive options available.
Title: Re: $20 LCR ESR Transistor checker project
Post by: morbid80 on May 19, 2016, 07:12:37 am
great news for those who have the new version Chinese LCR-T3/T4 ( slightly different board with 2 extra contact holes on the front) like mine. i found a useful tips from a buyer (1FebSA) on banggood product review, suggesting to use mega328_st7565_kit firmware instead, and modify CFLAGS += -DLCD_ST7565_V_FLIP=0 (value 1 -> 0) in the makefile.
 voila, my tester is now running on latest K firmware 1.12k.

attached is the transistortester HEX and EEP file. i suggest to set manually your contrast value after flashing. mine was set to 105.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on May 19, 2016, 09:38:05 am
Those holes look as if they're for substituting a through-hole crystal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: morbid80 on May 19, 2016, 12:13:01 pm
managed to flash a working M firmware 1.22m too, by using ST7565R, SPI LCD interface setting in the config.h file( need to uncomment #define LCD_FLIP_Y , and lcd _contrast set to 14 ).
however the display seems a little bit off, maybe the font size is big.
i keep getting 'battery? 3: 4mV' message during probing. can i know what is the cause?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 19, 2016, 01:02:53 pm
The problem with the display offset can be fixed by en/dis-abling LCD_OFFSET_X. 'battery? 3: 4mV' means, that the tester measured 4mV at probe pin #3 without any voltage applied. Please run the self-adjustment (see the readme for the procedure) and if that doesn't help increase CAP_DISCHARGED from 2 to 4.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rescator on May 19, 2016, 06:35:29 pm
Hello,

@morbid80

Thank you so much for sharing the solution.
It works fine on my tester identical to yours.

I tried to change several settings of the Makefile, without success. Now it's OK  :-+

Thanks again  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: caius on May 19, 2016, 10:55:11 pm
Hi all,
in your opinion which is the best DIY kit available at the moment?I thinking about this to replace my old M128 tester:

http://www.ebay.com/itm/321944016234 (http://www.ebay.com/itm/321944016234)
Title: Re: $20 LCR ESR Transistor checker project
Post by: johnka on May 30, 2016, 11:37:51 am
I got the GM328A v1.20 2015.05 from ebay. It came with 1.12k firmware. I removed the push button and install a rotary encoder like on this (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg690137/#msg690137) post from @firepower.
I tried to reflash it with a USBasp by editing the Makefile on mega328_GM328 folder. After powering it up there is something like scrolling text on the screen and it shuts down after 3 sec even with a component attached on probes. I even tried to flash with the default TransistorTester.hex there was in mega328_GM328 folder without any luck.
What should I do to fix it? Has anyone kept the original firmware of the GM328? What should I change in the Makefile?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2016, 12:05:19 pm
Anything about a low battery voltage? In that case, and if the battery is ok, you might have to check the voltage divider for measuring the battery voltage. Some clones use non-standard values for the resistors, but that can be adjusted in the source code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: johnka on May 30, 2016, 12:58:40 pm
Yes the voltage divider was wrong but it was not causing th problem. The resistors on the voltage divider on my board are 33K and 2.2K so I changed the voltage divider option to:
CFLAGS += -DBAT_NUMERATOR=352
CFLAGS += -DBAT_DENOMINATOR=22

edit: That was causing fasle battery reading at start (it was reading 34V so I changed them back to 133 and 33)

The problem is present even without the battery connected (when I have the USBasp connected in the ISP header pins.

edit: I had forget a -U parameter while flashing and the eeprom data were not loaded. After that it got fixed. The rotary encoder seems to work fine. Now I have to calibrate it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hansibull on May 30, 2016, 09:23:55 pm
Does anyone have any experience with the transistor tester with a color LCD? It's using the latest version (1.22), and got a built in IR receiver for protocol decoding. A picture from AliExpress (http://www.aliexpress.com/item/Transistor-tester-LCR-TC-finished-full-color-graphic-display/32664678347.html) indicates it can measure zener breakdown voltages above 4.7v as well!


(http://i.imgur.com/9thzVBM.jpg)

I haven't found any pics of the circuit board, and not a single review either.. Here's the Ebay link: http://www.ebay.com/itm/121959157850 (http://www.ebay.com/itm/121959157850)

Why should/shouldn't I buy this tester? Are there any better ones on the market that comes in a case as well?  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on May 30, 2016, 11:12:38 pm
Does anyone have any experience with the transistor tester with a color LCD? It's using the latest version (1.22), and got a built in IR receiver for protocol decoding. A picture from AliExpress (http://www.aliexpress.com/item/Transistor-tester-LCR-TC-finished-full-color-graphic-display/32664678347.html) indicates it can measure zener breakdown voltages above 4.7v as well!


(http://i.imgur.com/9thzVBM.jpg)

I haven't found any pics of the circuit board, and not a single review either.. Here's the Ebay link: http://www.ebay.com/itm/121959157850 (http://www.ebay.com/itm/121959157850)

Why should/shouldn't I buy this tester? Are there any better ones on the market that comes in a case as well?  :)
Color? What?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hansibull on May 31, 2016, 08:59:05 am
Color? What?

Yep, color LCDs have been supported since software version 1.19! It looks like a really decent tester for ~43$.

Code: [Select]
v1.22m 2016-03
- Added opto coupler check with display of the LED's V_f, the CTR and t_on/
  t_off delays (BJT types). 

v1.21m 2016-01
- Licensed under the EUPL V.1.1
- Improved storage managment of adjustment values and added support for
  two adjustment profiles.
- Added detection and decoding of RC-6 to IR detector. Solved issue with
  test button when the IR receiver module is removed too early. Added
  configuration switch to disable current limiting resistor for Vs in case
  of a 5V only IR receiver module.

v1.20m 2015-12
- Added IR RC detector and decoder function (requires TSOP IR receiver
  module).
- Changed MainMenu() to reduce RAM usage.

v1.19m 2015-11
- Implemented a fancy pinout displaying symbols and probe numbers for 3 pin
  semiconductors.
- Added color support.
- Changed ShowDiode() to output the number of diodes directy (not via
  Show_Fail() anymore) when more than 3 diodes are found (hint by
  hapless@eevblog).
- Extended LCD_ClearLine() in all display drivers to clear the remaining
  space of the current line to speed up things, especially for graphic
  displays The idea is to display the text first and then to clear the
  remaining space, instead of clearing the complete line and then printing the
  text.
- Added display driver for ILI9341/ILI9342 based modules. Thanks to
  Overtuner @ EEVblog forum for providing two LCD modules.
- Fixed problem with µ/micro character in font files.
- Fixed character issue (when larger than 8x8) in LCD_Char() for ST7565R.
- Updated Czech texts, thanks to Kapa.
- Fixed a minor issue in MenuTool(), when rolling over from last to first
  item.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on June 01, 2016, 02:27:25 pm
Color? What?

Yep, color LCDs have been supported since software version 1.19! It looks like a really decent tester for ~43$.

Code: [Select]
v1.22m 2016-03
- Added opto coupler check with display of the LED's V_f, the CTR and t_on/
  t_off delays (BJT types). 

v1.21m 2016-01
- Licensed under the EUPL V.1.1
- Improved storage managment of adjustment values and added support for
  two adjustment profiles.
- Added detection and decoding of RC-6 to IR detector. Solved issue with
  test button when the IR receiver module is removed too early. Added
  configuration switch to disable current limiting resistor for Vs in case
  of a 5V only IR receiver module.

v1.20m 2015-12
- Added IR RC detector and decoder function (requires TSOP IR receiver
  module).
- Changed MainMenu() to reduce RAM usage.

v1.19m 2015-11
- Implemented a fancy pinout displaying symbols and probe numbers for 3 pin
  semiconductors.
- Added color support.
- Changed ShowDiode() to output the number of diodes directy (not via
  Show_Fail() anymore) when more than 3 diodes are found (hint by
  hapless@eevblog).
- Extended LCD_ClearLine() in all display drivers to clear the remaining
  space of the current line to speed up things, especially for graphic
  displays The idea is to display the text first and then to clear the
  remaining space, instead of clearing the complete line and then printing the
  text.
- Added display driver for ILI9341/ILI9342 based modules. Thanks to
  Overtuner @ EEVblog forum for providing two LCD modules.
- Fixed problem with µ/micro character in font files.
- Fixed character issue (when larger than 8x8) in LCD_Char() for ST7565R.
- Updated Czech texts, thanks to Kapa.
- Fixed a minor issue in MenuTool(), when rolling over from last to first
  item.
What color displays are supported at this moment?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 01, 2016, 04:00:44 pm
What color displays are supported at this moment?

The m-firmware supports ILI9341/ILI9342 color displays, and the source framework allows to add other displays easily.

BTW, the next release will have:
- user-defined data lines for HD44780
- user-defined resistor divider for battery voltage measurement
- output of If for opto couplers
- serveral changes to add support for ATmega664/1284

Currently I'm trying to cope with KiCad :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hansibull on June 01, 2016, 05:15:13 pm
What color displays are supported at this moment?

The m-firmware supports ILI9341/ILI9342 color displays, and the source framework allows to add other displays easily.

BTW, the next release will have:
- user-defined data lines for HD44780
- user-defined resistor divider for battery voltage measurement
- output of If for opto couplers
- serveral changes to add support for ATmega664/1284

Currently I'm trying to cope with KiCad :)

While your at it, please add support for the ATmega32 and ATmega324 as well. The ATmega324 are almost identical to the ATmega328p, except more IOs. The ATmega32 (Dirt cheap at Ebay or Ali) is just an older model of the 324 with 4 instead of 6 PWM pins ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on June 02, 2016, 10:46:32 pm
What color displays are supported at this moment?

The m-firmware supports ILI9341/ILI9342 color displays, and the source framework allows to add other displays easily.

BTW, the next release will have:
- user-defined data lines for HD44780
- user-defined resistor divider for battery voltage measurement
- output of If for opto couplers
- serveral changes to add support for ATmega664/1284

Currently I'm trying to cope with KiCad :)
Are u
You going to release the project files in kicad KiCad? You're my hero!

There's kicad-users mailing list. If you wish some features and/or want to discuss them and even submit patches, there's kicad-developers mailing list too. You can ask developers at #kicad at irc.freenode.net by using freenode webchat or any IRC client. There's http://kicad.info forums too.

I'm not sure if there's a German KiCad community z maybe there are some linked in kicad-pcb.org top. I'd you want to make one, I'm sure they'll assist you at that (I think there's German KiCad users and developers too).

KiCad needs more developers and is far from perfect, but it's an active project with a supportive community. And unlike other EDA tools, it's FOSS and actively developed too ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 03, 2016, 09:56:16 am
While your at it, please add support for the ATmega32 and ATmega324 as well. The ATmega324 are almost identical to the ATmega328p, except more IOs. The ATmega32 (Dirt cheap at Ebay or Ali) is just an older model of the 324 with 4 instead of 6 PWM pins ;)

The ATmega324 shouldn't be any problem since it's part of the ATmega664/1284 line, just less flash/RAM/EEPROM. The ATmega32 is a little bit different, e.g. no 1.1V bandgap reference. I can't promise anything but I'll have a look into the ATmega32.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 03, 2016, 10:29:22 am
Are you going to release the project files in KiCad?

Seems so :) The dev board for the ATmega644/1284 is a tad too large for Eagle Freeware and I'm quite hesitant to buy a Make Personal license. Eagle has screwed up the printing in Linux (enforcing cups) and wasn't interested in fixing it. It also lacks some features I would expect from a commercial tool. So I'm getting used to KiCad. The UI is inconsistent, the workflow could be more convenient, the lib handling (paths, which lib to use) is :scared:, the signal names for busses are very constrained, but it has some nice ideas and features.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on June 03, 2016, 02:47:19 pm


Are you going to release the project files in KiCad?

Seems so :) The dev board for the ATmega644/1284 is a tad too large for Eagle Freeware and I'm quite hesitant to buy a Make Personal license. Eagle has screwed up the printing in Linux (enforcing cups) and wasn't interested in fixing it. It also lacks some features I would expect from a commercial tool. So I'm getting used to KiCad. The UI is inconsistent, the workflow could be more convenient, the lib handling (paths, which lib to use) is :scared:, the signal names for busses are very constrained, but it has some nice ideas and features.

It would be amazing if you provide some kind of technical report/Review-review of KiCad based on your experience.

Chris Palvina is interested in UI(X) improvements and is doing some changes, for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on June 11, 2016, 12:10:19 pm
Has someone already tested (or seen) this Component Tester?
http://www.ebay.com/itm/2016-DIY-Transistor-Tester-LCR-Capacitance-ESR-meter-Frequency-PWM-Generator-/191869802386 (http://www.ebay.com/itm/2016-DIY-Transistor-Tester-LCR-Capacitance-ESR-meter-Frequency-PWM-Generator-/191869802386)
It is available as Kit or already assembled version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: micro88 on June 11, 2016, 02:55:40 pm
The ebay page mentions

This item is DIY kits ,need solder it by yourself
The english manual ,pls contact us , send to your email , thanks


So looks like it is a kit to be assembled.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 11, 2016, 08:51:20 pm
That looks pretty nice as far as having the various connectors, rotary encoder, and color display. Unfortunately, they don't provide a photo of the unassembled PCB to see what else it has. Good price too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 11, 2016, 11:03:58 pm
Note that if you don't want to put it together, the following seller appears to offer the option of a fully assembled unit. Just select it from the drop down list labeled "Model", above the Quantity field.

http://www.ebay.com/itm/2016-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator-/252405848389 (http://www.ebay.com/itm/2016-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator-/252405848389)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on June 12, 2016, 08:11:43 am
There are different sellers on Ebay and AliExpress who have DIY and / or assembled ones.

It has some protection components too (P6KE6V8A and SRV05-4), like my 2015 EZM tester also has).

A picture I found:
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 12, 2016, 09:18:08 pm
Thanks for finding that pic. That looks like a nice model to get. I already have an earlier version, but this is very tempting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on June 13, 2016, 11:01:19 am
I have one that is almost like that one.  It came from Banggood.com as a kit.

Here is a thread on my site about it.
http://gokarters.com/smf/index.php?topic=2494.0 (http://gokarters.com/smf/index.php?topic=2494.0)

This unit has always worked well until recently.  There is a strange character on the display. It shows up in random locations so don't think it is a display problem?
Not sure if it is software related or what could be causing it.  I am not comfortable trying to read the 328. I do have the hardware to do it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on June 13, 2016, 12:40:50 pm
That banggood device does not have the protection components and
uses another LCD screen. The one I mentioned has a 160x128 pixel color display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on June 13, 2016, 03:42:28 pm
To Radio Tech:

I have the same devise and had the same problem.
On my unit the Atmega328 was locked and I fix the issue reprogramming it with this specific firmware.

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on June 13, 2016, 05:09:31 pm
To Radio Tech:

I have the same devise and had the same problem.
On my unit the Atmega328 was locked and I fix the issue reprogramming it with this specific firmware.

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)

Mauro

Thank you very much Mauro.  :-+
As I was thinking the files were corrupt or something. I have never put the board in a case and may have set it on something.
Now I have to learn how to program it since you directed me to the files.  I have the hardware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on June 13, 2016, 05:22:01 pm
You have several option and maybe you already have one of this on hand:
- Arduino as ICSP
- USBasp
- TL866 or some other stand-alone programmer
- BusPirate
.....

It should be nice to extend this list and to include the instruction on how to use each alternative :)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on June 13, 2016, 05:27:42 pm
You have several option and maybe you already have one of this on hand:
- Arduino as ICSP
- USBasp
- TL866 or some other stand-alone programmer
- BusPirate
.....

It should be nice to extend this list and to include the instruction on how to use each alternative :)

Mauro

I have 2 of the - USBasp  devices. One is a plain-Jane model and the other has jumpers on it.
About as far as I ever got was to flash a LED on a bread board but even then was quite a while ago.  Really need to get up to date on this stuff.
Thanks again for the direction.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on June 13, 2016, 05:45:55 pm
If you search for Usbasp in this thread you will find several messages from tom666.
He wrote several times how to use the usbasp to update this Transistor Tester, with all links to the software and the exact command to use.

If you will search on my posts you will find some pictures on how to wireup the ICSP connector on your tester

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on June 13, 2016, 06:02:42 pm
Thank you. Will give them both a search.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on June 13, 2016, 06:09:15 pm
I found the posts:

tom666 USBasp
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893)


tom666 Arduino
https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/msg879842/#msg879842 (https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/msg879842/#msg879842)

my message with the ICSP connector on the banggood tester
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg854124/#msg854124 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg854124/#msg854124)

my tester in the case
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=202981 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=202981)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on June 13, 2016, 07:03:53 pm
Links take me to sub forums and not the post.
I will search in thread later tonight after work ";) .


EDIT>>>>Found them :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on June 13, 2016, 07:23:35 pm
Yes, unfortunately the char $ ends the link and you need to copy/paste the entire string to get the correct link

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 13, 2016, 08:32:11 pm
Hmm... Let me try.

tom666 USBasp
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893)

tom666 Arduino
https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/msg879842/#msg879842 (https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/msg879842/#msg879842)

Mauro's message with the ICSP connector on the banggood tester
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg854124/#msg854124 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg854124/#msg854124)

Mauro's tester in the case
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=202981 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=202981)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on June 13, 2016, 10:19:51 pm
Thanks  :-+  I corrected my previous post  :)
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on June 14, 2016, 12:16:41 am
Interesting information. I may be able to do this.

I like the way you added the header to the device for programming also. Could do it on the bread board but have to locate the missing 8MHz crystals I ordered  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: ogara on June 14, 2016, 10:20:41 am
I bought a LCR T4 Mtester last year, graphic display, yellow PCB but only started on it now.  It starts up with only Mtester logo msg, no other version or model numbers visible. 

Did a upgrade apparently without issue, need only to change to "CFLAGS += -DLCD_ST7565_V_FLIP=1".  This is from the "transistortester-master\Software\trunk\mega328_st7565_kit\Makefile", which I understand is the "K" firmware.

I also try to upgrade to the "M" trendy firmware specifically 'ComponentTester-trendy-1.22m' but only ended up with a blank display.  Did tried playing with the obvious settings in the config.h but no luck getting the right combo.  I find its settings layout more daunting but is my tester even compatible with m-firmware?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 14, 2016, 11:03:25 am
Yes, ST7565 is supported by the m-firmware:
Code: [Select]
/*
 *  Chinese clone T3/T4 with ST7565 display
 *  - thanks to tom666 @ EEVblog forum
 */

//#if 0
#define LCD_ST7565R_SPI
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD4            /* port pin used for /RES */
#define LCD_A0           PD3            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD1            /* port pin used for SI (LCD's data input) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
#define FONT_8X8_V                      /* 8x8 font, vertically aligned */
#define SYMBOLS_24X24_V                 /* 24x24 symbols, vertically aligned */
//#endif

If you need to flip the y direction:
Code: [Select]
#define LCD_FLIP_Y                      /* enable vertical flip */

And if you got a small x offset enable or disable:
Code: [Select]
#define LCD_OFFSET_X                    /* enable x offset of 4 dots */
Title: Re: $20 LCR ESR Transistor checker project
Post by: ogara on June 14, 2016, 12:04:33 pm
Thanks, I tried again, enabling/disabling all 3 ST7565 section with LCD_FLIP_Y but still no display .  Any other switches I can try?  I have also tried changing the contrast numbers around.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 14, 2016, 12:23:01 pm
Is the LED lit when the tester is powered on? Rotary encoder?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ogara on June 14, 2016, 01:03:58 pm
It doesn't have a led but the LCD backlight does come on for some seconds and no addons yet, still factory default. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 14, 2016, 01:58:16 pm
And you've also updated the EEPROM?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ogara on June 14, 2016, 03:01:58 pm
Yes both ComponentTester.hex & ComponentTester.eep, using a batch file to flash to avoid mistakes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on June 14, 2016, 07:30:17 pm
Hi i new too this site just came across it whilst searching for some build instructions for this tester i have just brought can anyone help with a link etc many thanks in advance

http://www.ebay.co.uk/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.co.uk/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

just had a thought are the resistor values etc marked on the pcb already? i usually buy this type of tester pre built but thought i would have a go at building a kit form one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 14, 2016, 09:24:28 pm
Welcome to the forums, vinceroger.

The PCB has all the parts identified on it. So, build instructions generally aren't needed. Here are some tips:

1. Put the lowest components on first (e.g., resistors) and work your way up (IC sockets, capacitors, transistors, connectors).
2. Before installing the microcontroller and screen, power up the tester and verify the voltages on the IC socket and LCD connector. This is your only opportunity to make sure that you won't fry anything.
3. Once everything is working, be sure to calibrate it. Your kit may include an extra capacitor for this purpose.

The listing below has a photo of the assembled PCB without the screen that might be useful for reference:

http://www.ebay.com/itm/272165236396 (http://www.ebay.com/itm/272165236396)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timofonic on June 14, 2016, 10:10:17 pm
@c4757p
@madires

What about the madires' feedback? Is an interesting project and he might provide some interesting feedback.

Even better: If submitted to GitHub, many people would fork or and provide interesting modifications.

It's a popular product /project too, a cool "Made with KiCad" logo in the schematics and PCB would be interesting too!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 15, 2016, 10:50:13 am
Yes both ComponentTester.hex & ComponentTester.eep, using a batch file to flash to avoid mistakes.

Still no output at all? That's strange! Maybe some 5V<->3.3V issue with the display? The mega328_st7565_kit's Makefile has LCD_SPI_OPEN_COL disabled. So it must be something else. Unfortunately I don't got that T4 clone. If the manufacturers would send me their clones it would make things much easier.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on June 17, 2016, 09:41:24 am
Welcome to the forums, vinceroger.

The PCB has all the parts identified on it. So, build instructions generally aren't needed. Here are some tips:

1. Put the lowest components on first (e.g., resistors) and work your way up (IC sockets, capacitors, transistors, connectors).
2. Before installing the microcontroller and screen, power up the tester and verify the voltages on the IC socket and LCD connector. This is your only opportunity to make sure that you won't fry anything.
3. Once everything is working, be sure to calibrate it. Your kit may include an extra capacitor for this purpose.

The listing below has a photo of the assembled PCB without the screen that might be useful for reference:

http://www.ebay.com/itm/272165236396 (http://www.ebay.com/itm/272165236396)

Well the kit has just arrived the bad news is the pcb has none of  the parts identified on it bacically its mark r1 r2 c1 c2 etc no instructions either in the package and the seller hasnt got any either i will try to upload a picture later but without knowing what value resitor/capacitor etc goes where im a bit stuck.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 17, 2016, 11:31:19 am
The transistor tester's circuit is fairly simple and the clones are all based on the basic circuit in Karl-Heinz' doumentation. Please see https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf for the circuit. Why don't the sellers just put a note with the project's URL into the bag?  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 17, 2016, 03:36:32 pm
Unfortunately, most of the sellers that carry the various testers based on the original design know little to nothing about them. So, I doubt they'd even know where to get a link to the project and its documentation.

@vinceroger: Sorry to hear that the silkscreen on the model you received was so sparse. As madires said, you'll be able to refer to the original schematics to identify which component fits where. There isn't a huge variety of components, which makes the task less daunting than it might at first appear to be.

Take a photo of the bare board (both sides) before you begin. If you get stuck, you can post your questions and the pic here. After you've finished building and testing it, if you're so inclined, it'd be great if you could post an updated version of the photo with the component values inserted. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: ogara on June 17, 2016, 03:56:38 pm
Still no output at all? That's strange! Maybe some 5V<->3.3V issue with the display? The mega328_st7565_kit's Makefile has LCD_SPI_OPEN_COL disabled. So it must be something else. Unfortunately I don't got that T4 clone. If the manufacturers would send me their clones it would make things much easier.

It works now, my bad, I must have set and left the contrast higher while editing the config.h file.  The (M12864 DIY Transistor Tester) section with LCD_FLIP_Y disabled works best.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on June 17, 2016, 04:41:15 pm
Unfortunately, most of the sellers that carry the various testers based on the original design know little to nothing about them. So, I doubt they'd even know where to get a link to the project and its documentation.

@vinceroger: Sorry to hear that the silkscreen on the model you received was so sparse. As madires said, you'll be able to refer to the original schematics to identify which component fits where. There isn't a huge variety of components, which makes the task less daunting than it might at first appear to be.

Take a photo of the bare board (both sides) before you begin. If you get stuck, you can post your questions and the pic here. After you've finished building and testing it, if you're so inclined, it'd be great if you could post an updated version of the photo with the component values inserted. :-+

Im just measuring all the resistor values in the kit and also seeing what the four transistor part numbers are the rest i have already figured out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 17, 2016, 04:54:00 pm
That's great. You're quick. By the way, what speed crystal did they use on that model? 8 or 16 MHz?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on June 17, 2016, 05:02:12 pm
That's great. You're quick. By the way, what speed crystal did they use on that model? 8 or 16 MHz?

its a 8 mhz crystal
transistors are 2x c945 p331 1x 4673 4c gf 2 1x ws tl431 928
resistors x6 10k   x2 1k   x2 27k    x3 470k    x1 470 ohm   1x 33k  x3 680 ohm   x1 100k  x1 560 ohm  x2 3.3k   x1 2.2k there is also x1 brown looking type resistor but it only has 1 black band dead centre of it ('0' Ohm jumper) ive now been advised but there are 23 resistors in this kit plus the odd brown one but only 21 resistors fitted too the pcb when assembled thanks guys for any help you can offer me in building this kit.
                       
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 17, 2016, 08:02:05 pm
EZM328A files for johnka
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 18, 2016, 12:19:14 am
there are 23 resistors in this kit plus the odd brown one but only 21 resistors fitted too the pcb when assembled                       

I'm not quite sure I follow. You listed 23 resistors and I see 23 spots on the PCB for them (R1 - R24 minus R11, which isn't there).
Title: Re: $20 LCR ESR Transistor checker project
Post by: onlooker on June 18, 2016, 01:29:55 am
The PCB showed 2 R1s. One of the 2 should be R11. It may be misprinted or damaged.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 18, 2016, 02:52:49 am
Good eye! I see it now. The R1 next to R10 is probably R11.

So, there are spots for all 23 resistors and the zero-ohm jumper.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on June 18, 2016, 07:57:25 am
yes sorry about the confusion (was one of those days yesterday nothing went rite) i misscounted the ebay picture now just re checked the kit all again yes there are 24 spots on my pcb and also 24 resistors fitted too the pcb on the ebay picture  just re counted my resistors again 23 plus 1 zero ohm (which isnt shown in any ebay pictures) but without a scmematic to show what value resitor goes where and where also too fit the zero ohm one on the pcb im a bit stuck.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 18, 2016, 05:29:46 pm
No worries. I was having a rough day yesterday, too. It happens. Glad to hear things are coming together. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 18, 2016, 07:42:32 pm
GM328r stuffing list.
-------------------------------
r1 - 680r sensing circuit
r2 - 470k sensing circuit
r3 - 680r sensing circuit
r4 - 470k sensing circuit
r5 - 680r sensing circuit
r6 - 470k sensing circuit
r7 - 10k reset pullup
r8 - 33k power control
r9 - 3k3 power control
r10 - 27k
r11 - 100k (says r1 but is next to r10)
r12 - 10k voltage divider for battery sense
r13 - 3k3 voltage divider for battery sense
r14 - 560r display related - led current limit
r15 - 27k
r16 - 0r jumper for AVCC
r17 - 2k2 from tl431 to vcc
r18 - 1k rotary encoder current limit
r19 - 1k rotary encoder current limit
r20 - 10k rotary encoder pullup
r21 - 10k rotary encoder pullup
r22 - 470r frequency input dropper
r23 - 10k frequency input voltage divider
r24 - 10k frequency input voltage divider

rv1 - 10k preset frequency input voltage divider

u3 = tl431

q1 - 4673 (bc557c)
q2 - c945 (bc547)
q3 - c945 (bc547)

c1 - 22pf for crystal
c2 - 22pf for crystal
c3 - 100nf
c4 - 10nf
c5 - 100uf 25v
c6 - 100uf 25v
c7 - 100nf
c8 - 100nf
c9 - 100nf frequency input DC blocker
---------------------------------------------------
 8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on June 18, 2016, 07:57:12 pm
Thanks again stj i will try to build this up probably monday/tuesday as not back home untill then thanks again for your time working this all out i will update the thread when built.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ogara on June 18, 2016, 08:00:07 pm
Looks like for the Chinese tester, upgrading from the 78L05 regulator is highly recommended.

MCP1702 is often mentioned but if I read the datasheet correctly, its load regulation @ 1% is quite poor if you compared to the xxx1117 @ 0.2% or the LP2950 @ 0.05%! 

Seeing how bad the display flickers with the default 78L05, should more focus be on picking a LDO replacement with better load regulation?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 18, 2016, 08:57:41 pm
it already uses a 1117 for the 5v.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 19, 2016, 09:54:16 pm
Seeing how bad the display flickers[...]

It should not be doing that. Are you providing enough power for the regulator to start doing its job?
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on June 20, 2016, 10:02:30 am
Okay,I'm seriously considering getting one of these and I'm between these two:

http://www.ebay.com/itm/2016-EZM328-GM328-transistor-tester-ESR-frequency-meter-square-wave-genera-/322041933144?hash=item4afb31ed58:g:eIQAAOSwYlJW6Tg8 (http://www.ebay.com/itm/2016-EZM328-GM328-transistor-tester-ESR-frequency-meter-square-wave-genera-/322041933144?hash=item4afb31ed58:g:eIQAAOSwYlJW6Tg8)

http://www.ebay.com/itm/Digital-LCD-GM328A-Transistor-Tester-Capacitance-LCR-ESR-Meter-MOS-PNP-NPN-V2PO-/221960020347?hash=item33add9217b:g:~bYAAOSwHQ9WYnAG (http://www.ebay.com/itm/Digital-LCD-GM328A-Transistor-Tester-Capacitance-LCR-ESR-Meter-MOS-PNP-NPN-V2PO-/221960020347?hash=item33add9217b:g:~bYAAOSwHQ9WYnAG)

I like the EZM ones ,they seem nicely assembled and I don't mind not having a case.

Of these two I posted ? prefer the thru-hole build.
It also states that it has the new 1.12 firmware.("official firmware"?) but the cheaper build(2nd link) is a newer board revision.
I'm not really sure of the differences between these two.(I admit I didn't read the whole thread ^-^)

Which of these two should I be going with?
(other options are welcome)

Thanks:)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hansibull on June 20, 2016, 10:24:38 am
I got my TC1 component tester with color LCD (http://www.ebay.com/itm/121959157850) in the mail today, and I'll have to say I'm impressed! It got a step-up circuit for measuring zener diodes with a higher breakdown voltage of 4.7v. The battery is a rechargeable 3.7v Litium ion battery, that can be charged with a micro USB cable. Here are some pictures of it! (Open the pics in a new tab for even higher resolution)

(http://imgur.com/Aw9sO5v.jpg)

(http://i.imgur.com/xxsvSyi.jpg)

(http://i.imgur.com/Y8AgDZz.jpg)

(http://i.imgur.com/XIpxH17.jpg)

(http://i.imgur.com/cCoi3xB.jpg)

(http://i.imgur.com/wUdwspD.jpg)

(http://i.imgur.com/NFGia6m.jpg)

(http://i.imgur.com/nWvFI44.jpg)

(http://i.imgur.com/h9z6gkG.jpg)

(http://i.imgur.com/QOeriYd.jpg)

(http://i.imgur.com/mSp5OoV.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 20, 2016, 10:32:28 am
Don't worry about the firmware! You can update it anytime with the current k or m firmware. Which clone to buy isn't a simple decision. The EZM328 is through-hole and got a rotary encoder. The GM328A has an unpopulated ISP header and the SRV05-4 based input protection. If you're going to use the extra features, the rotary encoder would be very handy.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on June 20, 2016, 10:46:17 am
Okay,so I should go with the GM328R.

Will I need to update the firmware once I get it?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 20, 2016, 11:09:30 am
No, you don't need to update the firmware, but you can if you wish ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on June 20, 2016, 11:21:19 am
I obviously have no clue about how to do that but I think I'll have to buy a build first,start using it and go from there..
I believe I also need to start reading this thread from the start..

I'm a bit worried about that input protection the -A model has and the -R hasn't but I think it will be just a matter of caution before testing.(properly discharge caps etc)

I think the thru hole EZM seems a nice starting point regardless..
Title: Re: $20 LCR ESR Transistor checker project
Post by: hansibull on June 20, 2016, 11:30:11 am
No, you don't need to update the firmware, but you can if you wish ;)

The tester with the color LCD (the one I posted a few posts ago); is it possible to refresh it with your firmware without any major code modifications? Do the tester need a rotary encoder in order to be able to navigate in a menu, or can I use long/short press?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 20, 2016, 12:33:58 pm
The m-firmware supports ILI9341/9342 compatible color displays. If the TC1 got one of those, it should work. I assume that the IR receiver module is connected to a dedicated pin, but it's easy to modify the code for that (could become a hardware option). The user interface works fine with a simple push button or a rotary encoder, besides one feature. The squarewave generator is only enabled if a rotary encoder is available, because you don't select a preset frequency in a short list, like in the k-firmware. The frequency is tuned with the rotary encoder, also considering how fast you turn it, for an easy access to the full frequency range.

@all: If you want more displays to be supported, please send me the display or tester clone with a hint about the display controller and I'll try to write a driver.
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on June 20, 2016, 12:42:40 pm
I am interested in one , but I see there is no provision for surface mount components ?
I find the need for testing with SMD , because of learning repair still and the difficulty of IDing these parts .
Looks good .
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 20, 2016, 01:10:08 pm
I've seen several clones with test pads for different SMD packages. And if you don't find one suitable for your needs, make one yourself ;) The circuit is quite simple.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hansibull on June 20, 2016, 01:20:37 pm
@all: If you want more displays to be supported, please send me the display or tester clone with a hint about the display controller and I'll try to write a driver.

The LCD in the transistor tester looks identically to my ST7735S LCD module (http://www.ebay.com/itm/262092980703), which is a typical 128x160 TFT LCD. I think many users would like the code to support the Nokia 5110 LCD (http://www.ebay.com/itm/400488314619), even if the screen is a bit small. It's neat and dirt cheap at Ebay or AliExpress!

Oh, while you're here; why don't you host your code at Github instead? It makes it much easier to get in touch with the users, fix bugs, get help (by pull requests)  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on June 20, 2016, 10:03:43 pm
I am interested in one , but I see there is no provision for surface mount components ?
I find the need for testing with SMD , because of learning repair still and the difficulty of IDing these parts .
Looks good .
For 2 pin SMD parts you much better off with one of these.  You can get them on eBay (tweezer probe ~$2.5) and of course you can use them in circuit testing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 21, 2016, 11:40:34 am
The LCD in the transistor tester looks identically to my ST7735S LCD module (http://www.ebay.com/itm/262092980703), which is a typical 128x160 TFT LCD. I think many users would like the code to support the Nokia 5110 LCD (http://www.ebay.com/itm/400488314619), even if the screen is a bit small. It's neat and dirt cheap at Ebay or AliExpress!

I've had a quick look at the ST7735 datasheet. Looks familiar :) And the PCD8544 seems to be quite simple. I just need some samples ;)

Quote
Oh, while you're here; why don't you host your code at Github instead? It makes it much easier to get in touch with the users, fix bugs, get help (by pull requests)  :)

There's a mirror at Github ( https://github.com/svn2github/transistortester (https://github.com/svn2github/transistortester) ) and the two forums (this one and mikrocontroller.net) work fine for user interaction and support.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 21, 2016, 12:26:10 pm
For 2 pin SMD parts you much better off with one of these.  You can get them on eBay (tweezer probe ~$2.5) and of course you can use them in circuit testing.

Those SMD tweezers are really handy. The only drawback is when you press them too hard. It's amazing how far a 0603 resistor can fly. More food for the vacuum cleaner :)

Just an example for SMD test pads (and a nice enclosure):
(http://www.radiodevices.ru/ct/ct10-b2.jpg)
(http://www.radiodevices.ru/kiddy/kiddy-b2.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 21, 2016, 05:17:14 pm
Wow, that's quite the variety of test pads. I hadn't seen an enclosure like that before.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stryker on June 21, 2016, 11:28:10 pm
Just an example for SMD test pads (and a nice enclosure):
Have you seen anything similar to that SMT enclosure elsewhere?  Their US distributor doesn't list the product on their site, and they have nobody nearer to Australia for their particular product. 

Thanx, Geoff
Title: Re: $20 LCR ESR Transistor checker project
Post by: Radio Tech on June 22, 2016, 01:02:28 am
A big thanks to the fine folks of this thread.

My tester from Banggood come up with some strange characters on the display. After reading a lot in this thread and direct help from mauroh and reading Mardires post and Tom666 I was able to get mine reprogrammed and back up and running.

I made a video of the reprogramming on my YouTube channel and posted it here in the forums:
https://www.eevblog.com/forum/other-blog-specific/55-lcr-esr-transistor-checker-error-and-reprogram/new/#new (https://www.eevblog.com/forum/other-blog-specific/55-lcr-esr-transistor-checker-error-and-reprogram/new/#new)

Attached is a pic of the problem.

Many thanks again to the wonderful folks of this forum. :-+
I learned a little today.


https://www.youtube.com/watch?v=J_LYhHUS26c (https://www.youtube.com/watch?v=J_LYhHUS26c)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 22, 2016, 11:34:13 am
Have you seen anything similar to that SMT enclosure elsewhere?  Their US distributor doesn't list the product on their site, and they have nobody nearer to Australia for their particular product. 

Unfortunately not, just PCBs with a few SMD test pads. Have you asked the US distributor? Maybe they'll add the testers to their stock if there's demand. It's a nice design, not copied yet by the Chinese clone manufactures.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on June 22, 2016, 12:58:05 pm
Actually there are some Chinese $20 LCR testers that come with adapter for SMT parts for a long while but not as well done and integrated as the russian units.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on June 23, 2016, 09:11:07 am
Hi everyone,
I have this tester, building the kit is OK and it works OK.

http://www.ebay.nl/itm/191869802386?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.nl/itm/191869802386?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

My question: When I like to update firmware,
which firmware I have to use?
I don't know the display type.
What are the config bits settings?

I can use an minipro TLC866 programmer.

Thanks for advice.

BTW  Great project, thanks to devellopers and everyone who makes it better.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 23, 2016, 10:39:26 am
You can choose between k and m-firmware. The display is a ST7565. You might want to read https://www.eevblog.com/forum/other-blog-specific/55-lcr-esr-transistor-checker-error-and-reprogram/ (https://www.eevblog.com/forum/other-blog-specific/55-lcr-esr-transistor-checker-error-and-reprogram/) and watch the video. There's also a post with the pre-compiled m-firmware and the fuse settings (in the avrdude command line). Your programmer should be fine for the DIP ATmega.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on June 23, 2016, 11:40:11 am
Thank you Madires, I wil try as soon as posible,
with an spare mega328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 24, 2016, 06:47:54 am
Hi, friends! madires, Pukker is a few not such tester as you told. The display is constructed on the ST7735 controller on TFT technology. It has permission of 160x128 pixels. Are installed the power voltage on 3.3V and the transformer of levels on HCF4050 on a reverse side of the display. The Chinese firmware works normally, but it is locked for reading. If to load to k-firmware svn 669, then the image will be turned by 90 degrees. I drew the diagram of this tester and to send Karl-Heinz Kubeller, and also corrected files of source codes for turn of the image sent. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on June 24, 2016, 07:46:26 am
Hi indman and madires, thanks for your information.
I tried the ST7565 software and that didn't work.
But I can read the software from the controller.
I have read it out, programmed in an other processor and that works fine.
Software version shows 1.12k
Used TLC866 programmer for reading and writing.
Attachment files are the originals form the tester.

Thanks for your attention.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 24, 2016, 10:03:52 am
Pukker,thanks for an original firmware, I checked, it well works. But she is brought together on older revision and therefore has no additional opportunities. There is no inductivity measurement by a resonant method, the generator with the fixed frequencies. A pleasant bonus in the Chinese firmware that it is possible to change randomly through the menu color of a font and background. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 24, 2016, 10:48:45 am
Hi, friends! madires, Pukker is a few not such tester as you told. The display is constructed on the ST7735 controller on TFT technology. It has permission of 160x128 pixels. Are installed the power voltage on 3.3V and the transformer of levels on CD4050 on a reverse side of the display.

Ah, so that specific kit has a ST7735 display with a level shifter which is nice. The m-firmware doesn't support the ST7735 yet, but writing the driver should be easy since the protocol looks very similar to the ILI9341. I just need samples ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on June 24, 2016, 10:49:01 am
Indman, yes it is an older version.
BTW, kit looks good, pcb is OK, all parts are complete,
replaced the 680 and 470 resistors with 0.1% types and
replace TL431 with LM4040AIZ.
As far I can check, the measurements are accurate and OK.
Display a little small, but good readability.
And standard with protection parts mounted.
When it would become updatable it would be all good.

ehh, I'am Dutch, Englisch is not my native language.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 24, 2016, 11:50:07 am
Still I will add that commands for ST7735 are suitable also for the ILI9163 controller.  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 24, 2016, 12:46:54 pm
Thanks for the hint!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 24, 2016, 04:28:38 pm
Karl-Heinz Kübbeler added support of the discussed M328KitTFT clone in new revision of SVN 680. You watch a firmware in the "mega328_color_kit" folder :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on June 24, 2016, 05:12:42 pm
Thank you indman for the hint,
Thank you Karl-Heinz Kübbeler for the great support.
Programmed already and working fine.  :-+
Thanks. Great project.

BTW Programmed directly with the data en code files from Karl-Heiz Kübbeler,
used the config settings as read from original en posted in post 2130

Ha, better I could not get it.
Received yesterday, build yesterday, today newest sofware.
Karl-Heinz Kübbeler couldn't have better timing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 24, 2016, 06:15:01 pm
that's it - i'm getting one of those TFT displays for my GM328A unit.  8)
a nice upgrade  :-/O
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on June 24, 2016, 09:15:14 pm
that's it - i'm getting one of those TFT displays for my GM328A unit.  8)
a nice upgrade  :-/O

Yes, but for about $ 12.- you have an complete kit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 25, 2016, 12:17:28 am
but i have a heavily moded GM328A already, and the TFT display is only about £2.30
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 28, 2016, 01:04:56 pm
While working on a driver for PCD8544 compatible displays I'm looking into UJTs (not PUTs), but I haven't found any at my favoured shops. Do you know any source or could spare a few?
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheSteve on June 28, 2016, 04:47:27 pm
Hi everyone,
I have this tester, building the kit is OK and it works OK.

http://www.ebay.nl/itm/191869802386?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.nl/itm/191869802386?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

My question: When I like to update firmware,
which firmware I have to use?
I don't know the display type.
What are the config bits settings?

I can use an minipro TLC866 programmer.

Thanks for advice.

BTW  Great project, thanks to devellopers and everyone who makes it better.

I picked up one of these as well to experiment with. I'm happy to test any other firmware if needed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 28, 2016, 06:10:16 pm
Hiya Steve,

Is this your first of these testers or just this particular variation?
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheSteve on June 28, 2016, 06:25:06 pm
Hiya Steve,

Is this your first of these testers or just this particular variation?

It is the first of a tester like this. I have other test equipment that can do all of the same stuff but for the price it just seems it is worth buying one to play with. We also use Atmel AVRs at work and have a product or two that drive small displays so there is the possibility of re-purposing these kits. We can't buy all of the parts used in the kit in small quantities for the price of the entire kit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 28, 2016, 06:37:30 pm
Yeah, it's a neat little unit. I have one of the prior generation versions. The one you got has lots of updates to the hardware and costs less than mine from last year.

I know what you mean about cost of parts. Economies of scale certainly make it worthwhile to buy modules and kits for one-off (or a few-off) solutions, even if you're just borrowing parts from them.

Since you have other test equipment (LCRs and whatnot), it'd be interesting to see how this compares as far as applicability for certain uses. Obviously, $10-20 is no replacement for $$$ devices, but knowing when it's good enough and when it's not would be useful for those considering getting a kit for home/hobby use or more.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on June 28, 2016, 10:09:56 pm
I've bought the kit and it is a complete with al parts you need.
For the price you can't buy al the components en pcb is very good.
Handy is the DC jack, so I can Use and 12 Volt adapter,
no worry of dead battery when I need the tester. ^-^
Replaced the 680 and 470 resistors with 0.1% types and
replace TL431 with LM4040AIZ.
For better accuracy.
Main purpose for me is the ESR check for capacitors,
wich works very well.
checked with capacitor and the result was 210 uF and ESR 0.06 ohm.
with a resistor of 0.1 ohm in series I get 209 uF and ESR 0.16 ohm.
I have an good Fluke meter with capacity test which is good,
but capacity is not only important to check, ESR is also an important value
Very handy for checking what for transistor type is this and what is the pinout.
New version of software works fine. Revision 680
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 29, 2016, 01:30:27 am
does this colour-kit have a schematic or decent foto's of both sides of the board without the display fitted?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 29, 2016, 02:04:50 am
It's based on the original schematic. Photos of the PCB were posted a few dozen messages ago.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 29, 2016, 03:46:40 am
i found the top image, but no underside shot.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheSteve on June 29, 2016, 04:43:15 am
I was sent these three files, they are instructions, schematic and parts location. - I have not yet verified the schematic matches the board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 29, 2016, 05:10:07 am
i found the top image, but no underside shot.

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg964111/#msg964111 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg964111/#msg964111)  :-/O
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 29, 2016, 05:15:31 am
i found the top image, but no underside shot.

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg964111/#msg964111 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg964111/#msg964111)  :-/O

wrong kit - that's the GM328R from EZM studio, i'm looking for the TFT kit with the red pcb. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 29, 2016, 05:21:38 am
I see. Unfortunately, that was the only one I saw both sides of. :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: stryker on June 29, 2016, 05:48:31 am
Actually there are some Chinese $20 LCR testers that come with adapter for SMT parts for a long while but not as well done and integrated as the russian units.
They do look well constructed - have you bought a russian kit, or from that seller? 
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 29, 2016, 07:20:15 am
stj,Look according to this link, here I have all information on this clone and the photo.
https://yadi.sk/d/SPMZccK-smKEf    ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on June 29, 2016, 08:12:32 am


wrong kit - that's the GM328R from EZM studio, i'm looking for the TFT kit with the red pcb. :)

So, I don't know about the EZM studio, this is mine (see attached)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 29, 2016, 10:40:30 pm
that's what i was after - thanks.
i wanted to see where the smd protection diodes were fitted.

i also see a big space along the top edge - perfect for a 10pin programming header - perfect.
well almost - they should have included it in the design along with a 16MHz crystal.  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 29, 2016, 10:41:50 pm
Yeah, I was a bit surprised that after including the protection diodes, etc., that they didn't use a 16 MHz crystal. Odd.
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on June 30, 2016, 06:30:18 am
that's what i was after - thanks.
i wanted to see where the smd protection diodes were fitted.

i also see a big space along the top edge - perfect for a 10pin programming header - perfect.
well almost - they should have included it in the design along with a 16MHz crystal.  :palm:

Glad to help  :) , it also had me fixing on solder point and cropping off a a piece that was bothering me LOL, the things you notice in photos.

That would have been nice indeed. Got it from a seller alicehappy on ebay, it took 38 days to get here from HK for around 13 US.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on June 30, 2016, 08:05:05 am
Actually there are some Chinese $20 LCR testers that come with adapter for SMT parts for a long while but not as well done and integrated as the russian units.
They do look well constructed - have you bought a russian kit, or from that seller?
I got 3 Chinese LCR meters now.  So the next one need to have a big improvement to justify for my space.  I did bought a ESR meter from the Russia seller before.  Form factor is good, but has no input protection and my 2nd carelessness of putting a 12-50V charged cap killed it totally.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on June 30, 2016, 09:57:11 am
Got my M328-KIT-CTFT working after getting a replacement M328p IC.
Indeed, they used the older 1.12k firmware.

I would like to see the newer versions with color settings too :)

Here some pictures I took when I got the kit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 30, 2016, 12:57:41 pm
I would like to see the newer versions with color settings too :)

That's something for the ATmega664 or 1284. I'll put in on the to-do list just below touch screens ;) With the ATmega 664 we have enough pins (and flash memory) for driving touch screen controllers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 30, 2016, 01:21:49 pm

I would like to see the newer versions with color settings too :)

Hi, friends! Karl-Heinz Kubeller made new revision of a firmware of SVN 681 for a clone of M328KitTFT which allows to set up font color and back color through the menu. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 30, 2016, 05:18:33 pm
Got my M328-KIT-CTFT working after getting a replacement M328p IC.
Indeed, they used the older 1.12k firmware.

I would like to see the newer versions with color settings too :)

Here some pictures I took when I got the kit.

Wow, a lot going on on the inputs. Makes me wonder how high the stray inductance and capacitance are on this one. Also, what's the power consumption? Something tells me that a regular 9V battery won't survive very long in it even if the crystal remains at 8MHz, let alone 16.
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on June 30, 2016, 05:26:11 pm
About 23.27 mA

Edit, modified with average
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 01, 2016, 02:41:05 pm
Backlit color LCD + MCU with <25mA average during testing? OK, color me impressed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jasonmrc on July 01, 2016, 09:54:31 pm
I was sent these three files, they are instructions, schematic and parts location. - I have not yet verified the schematic matches the board.

I bought the same kit and i was sent the same files. looking at the schematic , the battery is wired funny/ wrong . both terminals looks like they are being shorted ..

i am looking in designing a case for this little test equipment .. and print it later !
Title: Re: $20 LCR ESR Transistor checker project
Post by: jasonmrc on July 01, 2016, 10:19:05 pm

I would like to see the newer versions with color settings too :)

Hi, friends! Karl-Heinz Kubeller made new revision of a firmware of SVN 681 for a clone of M328KitTFT which allows to set up font color and back color through the menu. :-+

look here if you want the english version
https://github.com/svn2github/transistortester
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 02, 2016, 06:11:34 am
given the present space situation,
i wonder how much bytes extra are needed for the colour display.

also, i'm sure most of you have seen the one sold by TomTop with a multi-colour display - be nice to get the code from that!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 02, 2016, 10:45:06 am
given the present space situation,
i wonder how much bytes extra are needed for the colour display.

Not much (directly), but driving the display becomes slow because the firmware has to send a lot more of data. For a monochrome display it's a byte for 8 dots. For a color display it's a color value (12-18 bits) for each dot. And since color displays usually got more dots anyway, it becomes even more worse. That also requires a larger font which increases the firmware size indirectly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 02, 2016, 05:53:56 pm
well that's an issue, i am already at the point of limiting the font size to keep the serial port.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 03, 2016, 08:38:09 am
What would just upgrading to a 16MHz clock do...
It could help a lot in this situation, not?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 03, 2016, 11:16:37 am
Not a lot, it's just a factor of two :) If you like to get an impression about the issue please watch a full screen clear for an ILI9341 based LCD. Anyway, a 16MHz crystal will also help with several measurements (inductance, capacitance, frequency) and the squarewave gen. And both firmwares support 16MHz for a long time now. Actually I'm surprised that most clones still got 8MHz crystals.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 04, 2016, 07:17:25 am
i would like to see someone work out the delays needed to run the atmel at it's rated 20MHz myself :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 04, 2016, 01:29:00 pm
Hmm, let's see what we would have to adapt (m-firmware):
- ADC clock
- add a section for 20MHz in wait.s
- change ESR meaurement to support a variable ADC clock

I think, for the k-firmware it's going to be more work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 04, 2016, 08:00:25 pm
you could overclock AVR's a lot too - maybe 24 or even 32MHz but i bet the first thing to mess up is the ADC/DAC circuits :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 05, 2016, 08:26:12 pm
I've done some changes and the next version of the m-firmware should support 20MHz (haven't tested that yet). And I got the first ST7735 display today and surprisingly the driver I've already written works fine. There must be something wrong :) But I think I'll add a 10x16 font which would fit perfectly (the display has 128x160 pixels),
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on July 06, 2016, 06:51:31 pm
Not a lot, it's just a factor of two :) If you like to get an impression about the issue please watch a full screen clear for an ILI9341 based LCD. Anyway, a 16MHz crystal will also help with several measurements (inductance, capacitance, frequency) and the squarewave gen. And both firmwares support 16MHz for a long time now. Actually I'm surprised that most clones still got 8MHz crystals.
Do you mean that the 8Mhz crystal can be replaced by an 16Mhz without any change of hard- and software?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 06, 2016, 07:06:14 pm
Not quite. When you change the crystal to a 16MHz type you have to re-compile the firmware for 16MHz (please see the Makefile).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on July 06, 2016, 07:37:22 pm
OK. I'am not familiar enough with AVR Studio and that kind of stuff,
Once  :-\ I will try to make myself familiar with that stuff and try to work with that stuff.
Thanks for your answer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 06, 2016, 08:02:29 pm
OK. I'am not familiar enough with AVR Studio and that kind of stuff,
Once  :-\ I will try to make myself familiar with that stuff and try to work with that stuff.
Thanks for your answer.

Im just trying to understand this avrdude etc stuff myself, as i have two testers i want to upgrade to 16 mhz etc the fitting of parts im fine with i just wish i could find a easy to understand guide on how to programe these testers as we are not probably the only people struggling with the programming side of things.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 06, 2016, 08:17:16 pm
tom666 has posted guides with instructions for several programmers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 06, 2016, 08:42:10 pm
I will have a look at them thanks and stj has been giving me some help too regarding issues ive been having etc once my programmer arrives i will have a go at upgrading them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 08, 2016, 06:38:18 pm
More updates from the developer's bench :) Meanwhile I've also received a PCD8544 display (aka Nokia 3310/5110 or LPH7366) and it's running fine with a 6x8 font. The PCD8544 has only 84 pixels in the X direction, so we get 14 characters per line (actually we need 16 at least). I've tried some smart line wrapping with a 8x8 font (10 chars per line), but it's not really feasable without increasing the firmware's size considerably. And a 5x8 font is way too small. So I went for the 14 chars/line compromise. By shortening some strings it should be possible to adapt the output to that limit. What else do we got? Yes, PUTs and UJTs. Right now I'm working on the detection of both and an issue with some JFETs. When that's finished I'll release the new version of the m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirKnowsALot on July 08, 2016, 09:32:14 pm
In the latest installment of my saga where I borked the AVR by carelessly issuing a bad avrdude command (post 2031), I wanted to let the group know that I replaced the 328 chip (no small feat since it is a TQFP  :phew: ) and was able to program 1.12k code (thanks to morbid80 in post 2039).  This solved my original problem of incorrect readings on caps and inductors with the original (knock-off) code.

If I get some more courage, I may try some other versions...
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 08, 2016, 10:13:03 pm
More updates from the developer's bench :) Meanwhile I've also received a PCD8544 display (aka Nokia 3310/5110 or LPH7366) and it's running fine with a 6x8 font. The PCD8544 has only 84 pixels in the X direction, so we get 14 characters per line (actually we need 16 at least). I've tried some smart line wrapping with a 8x8 font (10 chars per line), but it's not really feasable without increasing the firmware's size considerably. And a 5x8 font is way too small. So I went for the 14 chars/line compromise. By shortening some strings it should be possible to adapt the output to that limit. What else do we got? Yes, PUTs and UJTs. Right now I'm working on the detection of both and an issue with some JFETs. When that's finished I'll release the new version of the m-firmware.

i dont know why your bothering wih tiny displays,
i have been thinking about bigger ones (resolution-wise)
maybe one of those 320x240 TFT ones sold on ebay for arduino's.
i have read that a lot of those support SPI bus although it's not present on the arduino-pins.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on July 08, 2016, 11:39:30 pm
i dont know why your bothering wih tiny displays,
i have been thinking about bigger ones (resolution-wise)
Because we could make a combined digital watch / component tester perhaps??  :-DD Oops, lets not forget Snake!
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 09, 2016, 02:42:29 am
...and Tetris! Breakout, too!

On a more serious note, I've see these testers made into SMD test tweezers, so small displays are not as useless as they may seem. In addition, in some parts of the world certain components are easier and cheaper to come by than others, not to mention that you may just want to get the tester to work with the components that you have in your junk box (even if that includes an old phone).

The SMD tester that I looked at was using a tiny 16x2 screen. I was unpleasantly surprised to find out that m-firmware no longer gets updated for it. The k-firmware still uses "-ww-" (looks very strange to me) for coils and has other little things that make me prefer m for 16x2 and k for graphical displays.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 09, 2016, 08:13:20 am
not to mention that you may just want to get the tester to work with the components that you have in your junk box (even if that includes an old phone).

nice theory, not so easy to do.
i have lots of displays from old phones - connecting to them would be damn-near impossible without a comercially made pcb to get the connector-pitch.

the ones on ebay are on an adapter pcb.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 09, 2016, 10:49:54 am
i have been thinking about bigger ones (resolution-wise)
maybe one of those 320x240 TFT ones sold on ebay for arduino's.
i have read that a lot of those support SPI bus although it's not present on the arduino-pins.

ILI9341/ILI9342 is supported since v1.19m. The upcoming release will also have a bug fix for that controller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 09, 2016, 11:17:02 am
The SMD tester that I looked at was using a tiny 16x2 screen. I was unpleasantly surprised to find out that m-firmware no longer gets updated for it. The k-firmware still uses "-ww-" (looks very strange to me) for coils and has other little things that make me prefer m for 16x2 and k for graphical displays.

No worries! The trendy edition still supports HD44780 based displays (16x2 or more lines). The main difference is that the trendy edition got a simple abstraction layer for displays while the classic edition only supports 16x2 character displays. So the firmware of the trendy edition is larger (IIRC something in the range of 500 to 1000 Bytes for the display abstraction layer). My original idea was to keep the old 16x2 only edition for having more space left for new features, but it turned out that the difference in size isn't significant enough to run two editions. Simpy update your 16x2 tester with the current trendy edition and you'll have all the new features  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 09, 2016, 07:02:58 pm
Thank you for the clarification. That's good news!  :-+

not to mention that you may just want to get the tester to work with the components that you have in your junk box (even if that includes an old phone).

nice theory, not so easy to do.
i have lots of displays from old phones - connecting to them would be damn-near impossible without a comercially made pcb to get the connector-pitch.

the ones on ebay are on an adapter pcb.


Not a theory. It's been done. Proprietary connectors are always a pain, of course, but different old phones have their display connected differently. With a little patience, a few of them can be used out of the box... er... phone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: maxcombor on July 09, 2016, 09:58:23 pm
Hello to all , sorry for bad english . I have mega328_color_kit version and problem with compiling , error for frequency ../make_frequency.c:11: warning: 'wish_freq' may be used uninitialized in this function , if I turn frequncy off in  makefile before compiling everything pass ok and hex is without frequency option . What I`m doing wrong . Or if someone can compile for me in linux , i need 16mhz version or maybe 20mhz to test with external oscilator (or download location for mixed win-avr) if is problem in Outdated WINAVR software. thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: maxcombor on July 10, 2016, 07:57:58 am
I found solution , problem is with old WinAvr version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on July 13, 2016, 09:09:43 am
Hi Marcus,
   I see you just released the new trendy 1.23m, thanks!!
I tried it on my M12864 DIY kit and it works fine.
I will use it in the next days and give you a feedback only if I will find something strange.
If everything will be fine I'll just enjoy it :)
Do you have something specific you need to verify?

For all the lazy people around here :) : Attached you can find the compiled files for the M12864 DIY kit  :popcorn:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 13, 2016, 01:28:21 pm
You're welcome!

Do you have something specific you need to verify?

Some feedback about checking PUTs and UJTs would be helpful. Also reports on the PCD8544 and ST7735 display drivers, in case someome got a clone with such a display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dwaine on July 13, 2016, 09:02:36 pm
I got my TC1 component tester with color LCD (http://www.ebay.com/itm/121959157850) in the mail today, and I'll have to say I'm impressed! It got a step-up circuit for measuring zener diodes with a higher breakdown voltage of 4.7v. The battery is a rechargeable 3.7v Litium ion battery, that can be charged with a micro USB cable. Here are some pictures of it! (Open the pics in a new tab for even higher resolution)

I just order one of these units too.     I was wondering what processor is in the device.  Can I use the newer software listed here with the TC1?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 14, 2016, 11:41:07 am
Hi a while ago i posted about a esr kit i had brought from ebay
http://www.ebay.co.uk/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/331873741389?hash=item4d45376a4d:g:rrsAAOSwtJZXU~VA (http://www.ebay.co.uk/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/331873741389?hash=item4d45376a4d:g:rrsAAOSwtJZXU~VA)
i have finally managed to build this kit up with the help of a few members on here and badcaps.net but now we are stuck basically this kit comes with a atmega328p ic which has no data on the chip mine was full of ff when read with my tl866 so all what i get when i power on this tester is a brief screen flash i have tried various firmware etc but none seem to get this tester to work i have enclosed a picture of the tester and the back of the screen its on a 8mhz crystal at the moment but i will update it too 16mhz soon so if anyone can help with the files i need to program this tester it will probably help a few members out as on bad caps alone two of us so far are looking for these files and if the ebay seller has sold a few of these kits others will need them too many thanks guys.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 14, 2016, 01:53:54 pm
That seems to be a ST7920 display. You can find the precompiled k-firmware for that at https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_st7920 but I don't know if the settings match your kit. Could be also a known kit but with a different display.

BTW, does anyone like to sponsor a ST7920 display for the m-firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 14, 2016, 04:10:21 pm
we have tried that firmware, we just get a blank screen do you have any ideas what we can try next?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 14, 2016, 04:25:14 pm
Have you double-checked all components (values, pinout)? Even if the display doesn't show anything the tester should stay powered on for some seconds.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 14, 2016, 04:41:21 pm
Hi yes tester does stay on ok  just with a blank screen  i have brought a identical pre built tester so have swopped the atmega328p over to my kit tester and it works fine so has to be the ic, i have tried reading the working atmega328p ic with my promini tl866 and all what happens when you read the chip is a screen of ff s so maybe the chips are data protected some how? i want to get the kit tester working as a spare and upgrade it etc and if we can find the firmware that works it will help others out too who have brought these kits.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 14, 2016, 05:19:28 pm
Here is a picture of my meter assembled, I have bought the same one as vinceroger.
It was impossible for me yesterday night to see the color bands so I measured the resistors and put them in according to stj's nice reverse engineered component schematic (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg964934/#msg964934).
That said it's of course possible some of the resistors are 0.1% while some could be 1%, so no warranties there :)

I now tested another firmware: mega328_st7565 (https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_st7565) but the screen was blank with that as well.
Do note that our LCD has 9 pins, I note that most other testers use LCD's with a parallel connection and much more pins?

The meter stays on for ca 4 seconds with these firmwares, but stj posted another few on the thread at badcaps.net (http://www.badcaps.net/forum/showthread.php?p=672116#post672116) and with that I got some scrolling text on the screen. (Picture attached).
The behavior with all tested firmwares seems the same though: one press and red LED comes on, backlight comes on then meter turns off after 4 seconds.
With a 5 second long press meter stays on forever and I need to pull the battery to get it to turn off.
I theorize the problem is the same with all firmwares, it's just that the problem is visible with some firmwares :/
As vinceroger mentioned though he bought both the "DIY" meter like me and one preassembled and both his meters work fine with the pre-programmed chip from the seller!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 14, 2016, 06:54:41 pm
Since the tester stays on it's clearly a display problem. The first thing is to identify the display controller and then the pinout.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 14, 2016, 08:45:03 pm
it's using PD0-3

that's about it so far. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 15, 2016, 07:54:56 pm
Since the tester stays on it's clearly a display problem. The first thing is to identify the display controller and then the pinout.
Hi a update so with the help of stj on badcaps.net we have some more information that may help you i have uploaded a picture ot the lcd used on this tester and some information regarding connectors etc ive also checked on the main pcb which pin from the screen connector goes to which pin on the atmega328p ic i hope this information helps
this is from the ribbon cable of the lcd to pcb connector
1 - lcd /CE (gnd)
2 - lcd RST
3 - lcd A0
4 - lcd SCL
5 - lcd SDA
6 - +5v
7 - gnd
8 - led anode
9 - led cathode
this is from main pcb screen connector to the atmega ic
pin 9 goes to pins 22 and 8 gnds
pin 8 goes nc?
pin 7 goes to pins 22 and 8 gnds
pin 6 goes to pin 7 vcc and pin 20 avcc
pin 5 goes to pin 5 pd3
pin 4 goes to pin 4 pd2
pin 3 goes to pin 3 pd1
pin 2 goes to pin 2 pdo
pin 1 goes to pins 8 and 22 gnd
now stj has gave us various firmwares to try but none seem to work can you help guys please remember these ics that came with these kits read as no data on them so will need both files
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 15, 2016, 08:34:07 pm
Based on the picture of the LCD module it should be a ST7920, In Karl-Heinz' documentation the ST7920 is stated as "serial" with only three I/O pins (REST = PD0 / B0 = PD2 / EN = PD5). The ST7920 got Reset, CS, SID and CLK, but they got different functions in parallel interface mode. I think the best idea is to check the source code for the functions of the three I/O pins and then to adapt the port pins to match the hardware. You might need to add some code to drive the CS.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 15, 2016, 09:05:18 pm
Based on the picture of the LCD module it should be a ST7920, In Karl-Heinz' documentation the ST7920 is stated as "serial" with only three I/O pins (REST = PD0 / B0 = PD2 / EN = PD5). The ST7920 got Reset, CS, SID and CLK, but they got different functions in parallel interface mode. I think the best idea is to check the source code for the functions of the three I/O pins and then to adapt the port pins to match the hardware. You might need to add some code to drive the CS.
I have never done coding myself so i will ask stj if he or per hansson can help, or if anyone on this site can help modify the coding etc it will be appreciated then we can test these meters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 15, 2016, 09:47:36 pm
per hansson has been testing some firmware hes found two that sort of work can anyone modify the first one or have the makefile for the second one ? thanks
Quote from: Per Hansson;672803
This firmware works but display is upside down and inverted:
https://www.mikrocontroller.net/topic/248078?goto=4270706#4270706 (https://www.mikrocontroller.net/topic/248078?goto=4270706#4270706)

This firmware works, display is also oriented correctly. But no MakeFile is included.
https://www.mikrocontroller.net/topic/345717?goto=4278544#4278544 (https://www.mikrocontroller.net/topic/345717?goto=4278544#4278544)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on July 16, 2016, 07:02:24 am
Based on the picture of the LCD module it should be a ST7920
I do not think so.
Although the pic is of bad quality I'm quite shure it's a display like the fish8840's, ST7565.

When I tried my first flash with K.-H.'s Software my fish showed the same result as described above.
The problem is the contrast, with the default values I coudn't see anything.

Please refer to the manual how to change the contrast on startup or change the default in the makefile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 16, 2016, 07:08:30 am
tests will continue when they are awake. :)
i already built a couple of test files.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 16, 2016, 08:04:57 am
cheers stj i will give the files a try asap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 16, 2016, 10:06:38 am
per hansson has been testing some firmware hes found two that sort of work can anyone modify the first one or have the makefile for the second one ? thanks

So we got confirmation on the controller and the pinout. The next step is to tweak the settings for the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 16, 2016, 10:11:50 am
stj is helping us over on badcaps.net here is the link too the thread
http://www.badcaps.net/forum/showthread.php?t=50720&page=21 (http://www.badcaps.net/forum/showthread.php?t=50720&page=21)
im not sure if you have some firmware we can try too madires?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 16, 2016, 10:15:35 am
Based on the picture of the LCD module it should be a ST7920
I do not think so.
Although the pic is of bad quality I'm quite shure it's a display like the fish8840's, ST7565.

Of course I could be wrong. I've read "LCM_12864_V1.30" on the silkscreen and a quick search for "LCM_12864" lists mostly ST7920 based modules. But you never know :)

Quote
When I tried my first flash with K.-H.'s Software my fish showed the same result as described above.
The problem is the contrast, with the default values I coudn't see anything.

A default setting for contrast is tricky. It will work for most displays but not all. Maybe I should add something about that in the README.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 16, 2016, 10:19:47 am
im not sure if you have some firmware we can try too madires?

The m-firmware supports the ST7565, but not the ST7920 yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 16, 2016, 10:26:56 am
Ive never done any coding etc so sorry if any of these questions sound daft in any way as per has found two files that do make the tester work up to a point can these be modifed to work?

This firmware works but display is upside down and inverted:
https://www.mikrocontroller.net/topic/248078?goto=4270706#4270706 (https://www.mikrocontroller.net/topic/248078?goto=4270706#4270706)

This firmware works, display is also oriented correctly. But no MakeFile is included.
https://www.mikrocontroller.net/topic/345717?goto=4278544#4278544 (https://www.mikrocontroller.net/topic/345717?goto=4278544#4278544)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 16, 2016, 11:06:27 am
Based on the controller there are several settings in the Makefile for the k-firmware, such like flipping x or y. If you got the Makefile, change what's wrong and recompile the firmware. Karl-Heinz' documentation explains all the settings and tom666 has posted several guides on programming the ATmega.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 16, 2016, 11:49:12 am
Thanks for your help guys stj has just uploades some files and ive just programmed the tester although the firware is diffrent compared too my prebuilt kit it seems too work ok so far i will run some tests later regarding my prebuilt unit and this kit  ive built and loaded the firmware on and see if they read the same etc
Title: Re: $20 LCR ESR Transistor checker project
Post by: eeadata on July 16, 2016, 05:44:53 pm
I bought this gm328 type color tft lcd transistor lcr / esr kit . I built it but it did not work. When i press encoder switch screen backligt comes on with a white background nothing more.

? am new to atmel stuff. Where to check first ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 16, 2016, 06:01:39 pm
probably needs programming, a lot of kits seem to be shipped wih blank controllers!!

try to get a refund from the seller or a replacement chip first.
unless everybody does, they will keep getting away with it!

it's not a GM328 btw, those are from EZ-Electronics studio's
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 16, 2016, 09:59:15 pm
I bought this gm328 type color tft lcd transistor lcr / esr kit . I built it but it did not work. When i press encoder switch screen backligt comes on with a white background nothing more.

? am new to atmel stuff. Where to check first ?

Have you got a link too the tester you brought too see if its the same one we have been having issues with.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eeadata on July 16, 2016, 11:18:47 pm
This One.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 17, 2016, 03:45:11 am
situation is now,
meter looks working but is reading ESR of 0.00
the fix for the display was NOT using the eeprom for fonts!!!  :scared:

here is a post i just made over at badcaps.
----------------------------------------------------------------------------------------------
this whole situation is bullshit - i am starting to think the atmel's are bad.
 here is the makefile for the latest test version

 to break the display output you just need to change
Quote
# The USE_EEPROM option specify where you wish to locate fix text and tables.
 # If USE_EEPROM is unset, program memory (flash) is taken for fix text and tables.
 #CFLAGS += -DUSE_EEPROM

that should not happen.
 using the eeprom is standard - that's why it didnt work for so long!!
----------------------------------------------------------------------------------------

so there you have it, maybe the kits arent shipping blank, but the chips are defective.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Dwaine on July 17, 2016, 06:30:10 am
I got my TC1 component tester with color LCD (http://www.ebay.com/itm/121959157850) in the mail today, and I'll have to say I'm impressed! It got a step-up circuit for measuring zener diodes with a higher breakdown voltage of 4.7v. The battery is a rechargeable 3.7v Litium ion battery, that can be charged with a micro USB cable. Here are some pictures of it! (Open the pics in a new tab for even higher resolution)

(http://imgur.com/Aw9sO5v.jpg)

(http://i.imgur.com/xxsvSyi.jpg)

(http://i.imgur.com/Y8AgDZz.jpg)

(http://i.imgur.com/XIpxH17.jpg)

(http://i.imgur.com/cCoi3xB.jpg)

(http://i.imgur.com/wUdwspD.jpg)

(http://i.imgur.com/NFGia6m.jpg)

(http://i.imgur.com/nWvFI44.jpg)

(http://i.imgur.com/h9z6gkG.jpg)

(http://i.imgur.com/QOeriYd.jpg)

(http://i.imgur.com/mSp5OoV.jpg)

Nice.  I ordered one off eBay.  Can you update it with the existing github code?  Or you stuck with the existing firmware loaded on the device.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 17, 2016, 08:02:34 am
@eeadata :
I had the same issue, but got a programmed and working IC replacement for free.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eeadata on July 17, 2016, 08:14:20 am
any one have programming hex files for this tester ? Maybe i can be it programmed here .
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 17, 2016, 09:46:30 am
you mean the colour-tft one? they are posted a few pages back.

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg969074/#msg969074 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg969074/#msg969074)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 17, 2016, 10:45:40 am
For those of you following along regarding my previous post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg983525/#msg983525).
In my Mcumall GQ-4X programmer I have the buffer tab for the code (the HEX file) and the data tab for the eeprom (the EEP file)
I noticed the problem now, the data tab goes up to 3FF which is 1024 bytes.
So anything after that gets clipped...
Now you might want to blame the programmer and rightly so but I'm not sure what is being done here.
Looking at the specs for the Atmega328P (http://www.atmel.com/devices/atmega328p.aspx?tab=parameters) it has a 32KB flash area, an EEPROM of 1024 bytes and a SRAM of 2KB.
Looking at the EEP files all the ones that did not work are in the range of 2.5KB, so obviously they where clipped by the programmer.
But then again it means the SRAM and EEPROM area is being combined so I'm not sure how that is supposed to work...
Any idea how avrdude handles it? Because I see it's just specifying the file and to send it to EEPROM: "-U eeprom:w:TransistorTester.eep".
But since that's 1024 bytes in the specification does it just fill over into the SRAM or what?
And isn't the SRAM itself volatile memory? Or did Atmega simply use flash for it to save on costs?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 17, 2016, 11:17:35 am
The HEX and EEP files are the firmware in Intel encoded format, not any direct binary image.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 17, 2016, 12:06:30 pm
Aww thanks!
When I open the firmware file for the flash my programmer asks if it should be in Intel encoded format which I answer yes to.
Next for the eeprom "data" window I simply used drag and drop.
It does not ask then about the format so I assumed it uses the same as for the flash.
Well turns out that is not what happens at all!
The files I've tested are named TransistorTester.hex for the flash and TransistorTester.eep for the EEPROM.
Well turns out if I rename the TransistorTester.eep to "Something.hex" it also does not ask about encoding format.
But it does then convert it to Intel encoded format!

And now while testing it some more to get some screenshots it always converts even the eep file to Intel hex without asking!
Murpy's law!!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 17, 2016, 12:16:46 pm
Aww thanks!
When I open the firmware file for the flash my programmer asks if it should be in Intel encoded format which I answer yes to.
Next for the eeprom "data" window I simply used drag and drop.
It does not ask then about the format so I assumed it uses the same as for the flash.
Well turns out that is not what happens at all!
The files I've tested are named TransistorTester.hex for the flash and TransistorTester.eep for the EEPROM.
Well turns out if I rename the TransistorTester.eep to "Something.hex" it also does not ask about encoding format.
But it does then convert it to Intel encoded format!

And now while testing it some more to get some screenshots it always converts even the eep file to Intel hex without asking!
Murpy's law!!!

I was having issues with my programer so i messaged a user on here who had the exact programer as mine this was his relpy
This is the picture with the correct settings for the programmer.
https://www.dropbox.com/s/zqacxby4ayngy2c/Fuses%20on%20TL866A.jpg?dl=0 (https://www.dropbox.com/s/zqacxby4ayngy2c/Fuses%20on%20TL866A.jpg?dl=0)

The only thing you need to do is to load the TransistorTester.hex in the "Code Memory" and the TransistorTester.eep in the "Data Memory"
Pay attention and use always "INTEL HEX" as File Format when you load the files. By default the TransistorTester.eep will be recognized as Binary and you have to change it during loading.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 18, 2016, 07:01:23 am
@madires

your 20MHz build for M328p is broken.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 18, 2016, 07:14:34 am
latest trendy build for GM328A/r units.

one day i may consider the trendy useable, but not while it interprets the button as up/down making it a bastard to actually use the menu's with an encoder!
 :palm:

K version has similar problems - but i patched most of that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 18, 2016, 09:00:56 am
@madires

your 20MHz build for M328p is broken.

Thanks for the feedback! I haven't tested it myself yet. Could you please a little bit more specific?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 18, 2016, 09:04:35 am
not really, stupid "programmers notepad" IDE wouldnt let me copy/paste from the feedback window. :(

in simple terms, it wouldnt build because of something missing.
take the zip i just posted, it has the changed configs in it. ( in the interests of "open-source"  :-+ )
use those and change it to 20MHz - that will give you what i was running.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 18, 2016, 09:16:36 am
latest trendy build for GM328A/r units.

one day i may consider the trendy useable, but not while it interprets the button as up/down making it a bastard to actually use the menu's with an encoder!
 :palm:

In case you haven't noticed it, in the m-firmware the menu is controlled differently for a push button and a rotary encoder:

Pushbutton only:
-  short key press for next item
-  long key press for running item

Rotary encoder:
- left/right for previous/next item
- key press for running item

If you enabled the rotary encoder you can't up/down the menu items with the button, unless you got a very poor rotary encoder creating right/left pulses when pressing the push button.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 18, 2016, 09:20:21 am
encoder works fine,
what i mean is - example.
i go to the contrast setting, use the encoder to get the value,
then press the button and the value changes instead of exiting or something.


what i did on the K firmware was add some "else" statements into the code for the encoder so if an encoder is enabled, some of the button functions are not used.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 18, 2016, 09:57:11 am
what i mean is - example.
i go to the contrast setting, use the encoder to get the value,
then press the button and the value changes instead of exiting or something.

I see. The common way to exit any tool/feature is to press the push button twice. It's the same for the rotary encoder to keep the UI consistent. I understand that some people would prefer a simple key press for exiting. Actually, you're the first one complaining about that. Implementing a single-push-exit  would require to write two versions of most tools/features, because the UI and actions (loop logic) are interwoven. And it's already hard enough to support all the different hardware options. I'll put it on the to-do list, but way down in the nice-to-have section.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 18, 2016, 10:59:06 am
in simple terms, it wouldnt build because of something missing.
take the zip i just posted, it has the changed configs in it. ( in the interests of "open-source"  :-+ )
use those and change it to 20MHz - that will give you what i was running.

So far it worked as intended ;) For 20MHz you need to adjust the ADC clock in config.h to 156250Hz:

Quote
//#define ADC_FREQ    125000
#define ADC_FREQ    156250

That's required because of the limited ADC clock prescaler, it supports only 2, 4, 8, 16, 32, 64 and 128. As I noted before, I haven't tested the 20MHz MCU clock rate yet, but I'd appreciate if someone does (less work for me :).

BTW, the current version under development supports JFETs with (very) low I_DSS, e.g. PN4117A, and also handles Germanium BJTs with high leakage current now. Those were detected as JFET when the leakage current was >700µA. Are there any p-channel JFETs with very low I_DSS? I've got only n-channel types.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 19, 2016, 06:53:03 pm
Do Germanium diodes still need to be cooled down?

Also, is there any noticeable advantage in going up to 20MHz from 16?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 19, 2016, 07:48:16 pm
Yes, cooling helps with problematic Germanium diodes. I haven't looked into this yet since I got only one of those for testing. The typical A118 and AA143 are detected correctly without cooling. The 20 MHz MCU clock could improve some measurements slightly in theory and it allows higher frequencies for the squarewave generator. It's still untested (but on my to-do list). Currently I don't see any particular reason for 20MHz. So don't get too excited ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: dimitrov2000 on July 20, 2016, 05:21:06 pm
Hi guys,
A little help here, please.
Just received my unit from China and it seems to work quite well for now.
There is only one thing that's driving me mad:
Where the heck I have to connect signal and ground to measure frequency?
When I activate the option from the menu the display says: 0 Hz, waiting for input signal.
Tried all the available 3 pins - no luck. Reading the original authors manual, says the frequency
is measured at pin 6 of the chip, followed by long, long explanation for the accuracy of the measurement...
No word about input socket or pins. I see at the oldest versions there are pins: "F-In" or something similar.
Here there is nothing. I doubt that I have to solder directly on pin 6, right?
Help please...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 20, 2016, 06:19:08 pm
Please read section "2.2.4 Frequency Measurement" in Karl-Heinz' documentation. There's a nice circuit you'll need for the frequency counter. The manufacturer of your clone enabled the frequency counter in the firmware without adding the necessary circuitry.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dimitrov2000 on July 21, 2016, 06:12:14 am
Thank you. I'll read it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 22, 2016, 07:17:48 pm
Yes, cooling helps with problematic Germanium diodes. I haven't looked into this yet since I got only one of those for testing. The typical A118 and AA143 are detected correctly without cooling.

After trying several ideas I've found a way to support Germanium diodes with very low Vf, when measured with Rh (470k). I think, it will also help with Germanium diodes with a high leakage current, but I don't got any of those for testing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bmht on July 22, 2016, 08:56:53 pm
Hello guys
This is my fist post here

My unit arrived from China and after assembly when I try to turn it on the LCD just flickers  or stays lit if I keep the rotary button pressed but nothin else on the screen.
I have measured the voltage between pins 7 and 22 and I got 5 volts.

I'm hoping that you guys if you know could lead me to a solution?
I do not know exacly wich is the firmware I would have to download for this specific model or how to do it
I got an USBASP and I would really appreciate if you guys could point me to a solution.
Sorry if my english is bad since it's not my mother language.
I post some images

(http://i65.tinypic.com/2d0grph.jpg)

(http://i63.tinypic.com/2vvu8om.jpg)

(http://i65.tinypic.com/j14rjq.jpg)

Here is the flicker

(http://i63.tinypic.com/2dwagc8.jpg)



Thanks
Belen
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 22, 2016, 09:03:15 pm
Does the display stay powered on for a few seconds after pressing the rotary encoder?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bmht on July 22, 2016, 10:14:58 pm
Does the display stay powered on for a few seconds after pressing the rotary encoder?
Dear madires
If I keep pressing the button it stays lit
other wise it turn of

a small press (like to turn it on) with turn on the display as soon as I remove the finguer from the button of the rotary encoder it turns off

I hope I made myself clear enough

Thanks
Belen
Title: Re: $20 LCR ESR Transistor checker project
Post by: bmht on July 23, 2016, 02:16:07 am
I will try to program the chip based on what I have already read with an USBASP

I got a question if anyone knows
it is really necessary to use a 8 Mhz Crystal for program the chip with the USBASP? The only one I got now is the one on the component tester and I have to desolder that to be able to program the chip, then solder back again again to test and so on.

Or I can desolder the Crystal and solder a 16 Mhz Crystal in the tester? I do have spare 16 Mhz Crystals.
But from where I live there is no electronics shops open for the weekend so I will have to wait until next Monday or go through the soldering desodering procedure.

Thanks
Belen

Title: Re: $20 LCR ESR Transistor checker project
Post by: bmht on July 23, 2016, 02:18:57 am
Sorry about this
I just looked that I removed the Atmel chip and the tester flickered the same just turn on the display while I had the rotary encoder button pressed.
So it's the same behavior with chip or without chip inserted

Maybe the chip is blank?
I will try to reprogram and let you all know about the results
Thanks anyhow
Belen
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydrawerk on July 23, 2016, 02:57:04 am
Well, I prefer a simple two-line LCD with a HD44780 controller. It can be easily replaced when broken. I hope that a LCD with HD44780 will be available almost forever.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dimitrov2000 on July 23, 2016, 05:14:20 am
"Often this problem is the reason, if the tester starts with the
button hold pressed, but switch o directly by releasing. The problem is enforced by a high
current background light for the LCD. The resistor R7 to the base of the PNP transistor T3 was
optimized with the value 27k
 too much to save power consuming. To improve the switching
with lower battery voltage or lower current ampli cation factor of the PNP transistor T3, you
should reduce the resistance to 3:3k." Quote from the 1.1.1 manual
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 23, 2016, 07:35:13 am
@bmht: As earlier written: It seems that some of these kits are delivered with a blank chip!
I wrote the seller what the effect was with it and I got a free replacement chip, which works.

To program the chip yourself, see the original readout program files here:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg969074/#msg969074
Title: Re: $20 LCR ESR Transistor checker project
Post by: bmht on July 23, 2016, 12:31:36 pm
Dear all

The tester doesn't turn not. When I press the rotary button the LCD lits and as soon as I release the button it turns off.
I tried to reprogram the chip using the files from mega328_st7565_kit (the last ones on the site).
TransistorTester.eep dated 4/21/2016
TransistorTester.hex dated 7/9/2016

but I do not know it it was success or not here is my result.

C:\AVR>avrdude -c usbasp -p m328p -F -B 4.0 -e -U flash:w:"TransistorTester.hex"
:i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U e
fuse:w:0x04:m

avrdude: set SCK frequency to 187500 Hz
avrdude: warning: cannot set sck period. please check for usbasp firmware update
.
avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

avrdude: Device signature = 0x1e950f
avrdude: erasing chip
avrdude: set SCK frequency to 187500 Hz
avrdude: warning: cannot set sck period. please check for usbasp firmware update
.
avrdude: reading input file "TransistorTester.hex"
avrdude: writing flash (29952 bytes):

Writing | ################################################## | 100% 20.10s

avrdude: 29952 bytes of flash written
avrdude: verifying flash memory against TransistorTester.hex:
avrdude: load data flash data from input file TransistorTester.hex:
avrdude: input file TransistorTester.hex contains 29952 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 15.55s

avrdude: verifying ...
avrdude: verification error, first mismatch at byte 0x0000
0x00 != 0x2d
avrdude: verification error; content mismatch

avrdude: safemode: lfuse changed! Was f7, and is now 8c
Would you like this fuse to be changed back? [y/n] n
avrdude: safemode: hfuse changed! Was df, and is now 0
Would you like this fuse to be changed back? [y/n] n
avrdude: safemode: efuse changed! Was 1, and is now 6
Would you like this fuse to be changed back? [y/n] n
avrdude: safemode: Fuses OK (E:01, HF, L:F7)

avrdude done. Thank you.

I got a spare blank chip. do you think I should try with that one? In case it doesn't work will I be able to reprogram my spare for use with arduino?

I'm sorry to be this cheap but where I live those chips are not easy to come by and bringing them in here is expensive.

Thank you all for your help
Belen
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strada916 on July 23, 2016, 01:05:06 pm
Looking at the error feedback. Looks like clock speed is not right.

I'm no expert. It's just what I see in your post.

Sent from my SM-G925I using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 23, 2016, 01:07:24 pm
http://www.badcaps.net/forum/showpost.php?p=674892&postcount=519 (http://www.badcaps.net/forum/showpost.php?p=674892&postcount=519)

replied to your other post.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dimitrov2000 on July 23, 2016, 01:45:50 pm
Please read section "2.2.4 Frequency Measurement" in Karl-Heinz' documentation. There's a nice circuit you'll need for the frequency counter. The manufacturer of your clone enabled the frequency counter in the firmware without adding the necessary circuitry.

Thanks man, I build the circuit and I'm just about to test as soon as I find good variable frequency source.
By the way, does anyone knows what is the variable potentiometer for?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strada916 on July 23, 2016, 01:49:51 pm
Please read section "2.2.4 Frequency Measurement" in Karl-Heinz' documentation. There's a nice circuit you'll need for the frequency counter. The manufacturer of your clone enabled the frequency counter in the firmware without adding the necessary circuitry.

Thanks man, I build the circuit and I'm just about to test as soon as I find good variable frequency source.
By the way, does anyone knows what is the variable potentiometer for?
Screen contrast?

Sent from my SM-G925I using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: dimitrov2000 on July 23, 2016, 01:51:59 pm
It seems no. I tried it very carefully but nothing happens.
I'm afraid to try it harder because it can be some calibration...
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on July 23, 2016, 01:55:12 pm
... I tried to reprogram the chip using the files from mega328_st7565_kit ...

For your tester (with TFT display) is designed firmware in the folder "mega328_color_kit".
You can use the firmware from the attached zip file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 23, 2016, 02:28:39 pm
It seems no. I tried it very carefully but nothing happens.
I'm afraid to try it harder because it can be some calibration...

All self-adjustment is done in software. The only reason for a potentiometer would be the display, if it doesn't got a software controlled contrast.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dimitrov2000 on July 23, 2016, 02:33:28 pm
It does have software contrast adjustment. That's why I wonder.
Judging by the trace in the unit's back (my second picture few posts above)
it seems to be related to the display. Maybe the background light,
but it does nothing....
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 23, 2016, 02:53:41 pm
it's an old design board - probably originally fitted with a character display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: maxcombor on July 23, 2016, 11:50:04 pm
To bmht answer , i was order three peaces , same like yours (all of them came with a same simptoms) and all 3 are with a blank atmega 328 ,reprogram with a "mega328_color_kit" firmware and all is ok .
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 24, 2016, 09:21:16 am
To bmht answer , i was order three peaces , same like yours (all of them came with a same simptoms) and all 3 are with a blank atmega 328 ,reprogram with a "mega328_color_kit" firmware and all is ok .

have you got a link to the firmware you found that worked ok for these testers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: maxcombor on July 24, 2016, 09:55:14 am
The official link is down from yesterday ???
Here in attachment you have all you need.
Title: Re: $20 LCR ESR Transistor checker project
Post by: maxcombor on July 24, 2016, 10:14:02 am
And if you like to cook your version here is complete trunk folder (last version), i`m changed to 16mhz and direction of rotary encoder ,works perfect. Because maximum single file size for upload is 1Mb  i was splited in three peaces ,just remove .jpg extension and open with winrar or winzip ,leave only trunk.z01 ,trunk.z02 , trunk.z03
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on July 24, 2016, 10:38:49 am
SVN repository (mirror on github):
https://github.com/svn2github/transistortester (https://github.com/svn2github/transistortester)
Download:
https://github.com/svn2github/transistortester/archive/master.zip (https://github.com/svn2github/transistortester/archive/master.zip)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on July 24, 2016, 11:25:01 am
Regarding the programming now we are seeing there are a lot of the kits being sold with blank ics theres going to be a lot of people unsure how to programme them, it would be great if someone had the time too upload a video/guide with step by step instructions on how to use avrdude/USBASP and add the hex files etc check the fuses and programme the ic solely to programme these esr testers as a lot of newbies like myself have probably never done programming, i have been looking for a good video guide with step by step instructions but have not found a good one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 24, 2016, 11:50:24 am
I think, such a how-to-program-my-transistor-tester video for beginners should be done by a beginner, because he's got the best point of view for the issues and things important to beginners. For me it's just plugging in the programming cable and a "make upload".
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 24, 2016, 01:02:29 pm
To get real cheap atmega328pu IC's, try:
http://www.aliexpress.com/item/Free-shipping-1pcs-LOT-NEW-ORIGINAL-ATMEGA328P-PU-ATMEGA328-Microcontroller-DIP28/32617642721.html?spm=2114.01010208.3.1.Bmwzel&ws_ab_test=searchweb201556_8,searchweb201602_2_10057_10056_10055_10037_10049_10033_10059_10032_10058_10017_405_404_10040_10060,searchweb201603_6&btsid=24595642-06bc-4553-b4b2-2c571ea87172 (http://www.aliexpress.com/item/Free-shipping-1pcs-LOT-NEW-ORIGINAL-ATMEGA328P-PU-ATMEGA328-Microcontroller-DIP28/32617642721.html?spm=2114.01010208.3.1.Bmwzel&ws_ab_test=searchweb201556_8,searchweb201602_2_10057_10056_10055_10037_10049_10033_10059_10032_10058_10017_405_404_10040_10060,searchweb201603_6&btsid=24595642-06bc-4553-b4b2-2c571ea87172)
or
http://www.aliexpress.com/item/Free-shipping-5pcs-LOT-NEW-ORIGINAL-ATMEGA328P-PU-ATMEGA328-Microcontroller-DIP28/32617609717.html?spm=2114.01010208.3.17.pZRTBj&ws_ab_test=searchweb201556_8,searchweb201602_2_10057_10056_10055_10037_10049_10033_10059_10032_10058_10017_405_404_10040_10060,searchweb201603_6&btsid=24595642-06bc-4553-b4b2-2c571ea87172 (http://www.aliexpress.com/item/Free-shipping-5pcs-LOT-NEW-ORIGINAL-ATMEGA328P-PU-ATMEGA328-Microcontroller-DIP28/32617609717.html?spm=2114.01010208.3.17.pZRTBj&ws_ab_test=searchweb201556_8,searchweb201602_2_10057_10056_10055_10037_10049_10033_10059_10032_10058_10017_405_404_10040_10060,searchweb201603_6&btsid=24595642-06bc-4553-b4b2-2c571ea87172)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on July 24, 2016, 01:02:54 pm
@vinceroger
LCR ESR Transistor checker error and reprogram (https://www.eevblog.com/forum/other-blog-specific/55-lcr-esr-transistor-checker-error-and-reprogram/new/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on July 24, 2016, 04:35:01 pm
To get real cheap atmega328pu IC's, try:
http://www.aliexpress.com/item/Free-shipping-1pcs-LOT-NEW-ORIGINAL-ATMEGA328P-PU-ATMEGA328-Microcontroller-DIP28/32617642721.html?spm=2114.01010208.3.1.Bmwzel&ws_ab_test=searchweb201556_8,searchweb201602_2_10057_10056_10055_10037_10049_10033_10059_10032_10058_10017_405_404_10040_10060,searchweb201603_6&btsid=24595642-06bc-4553-b4b2-2c571ea87172 (http://www.aliexpress.com/item/Free-shipping-1pcs-LOT-NEW-ORIGINAL-ATMEGA328P-PU-ATMEGA328-Microcontroller-DIP28/32617642721.html?spm=2114.01010208.3.1.Bmwzel&ws_ab_test=searchweb201556_8,searchweb201602_2_10057_10056_10055_10037_10049_10033_10059_10032_10058_10017_405_404_10040_10060,searchweb201603_6&btsid=24595642-06bc-4553-b4b2-2c571ea87172)
or
http://www.aliexpress.com/item/Free-shipping-5pcs-LOT-NEW-ORIGINAL-ATMEGA328P-PU-ATMEGA328-Microcontroller-DIP28/32617609717.html?spm=2114.01010208.3.17.pZRTBj&ws_ab_test=searchweb201556_8,searchweb201602_2_10057_10056_10055_10037_10049_10033_10059_10032_10058_10017_405_404_10040_10060,searchweb201603_6&btsid=24595642-06bc-4553-b4b2-2c571ea87172 (http://www.aliexpress.com/item/Free-shipping-5pcs-LOT-NEW-ORIGINAL-ATMEGA328P-PU-ATMEGA328-Microcontroller-DIP28/32617609717.html?spm=2114.01010208.3.17.pZRTBj&ws_ab_test=searchweb201556_8,searchweb201602_2_10057_10056_10055_10037_10049_10033_10059_10032_10058_10017_405_404_10040_10060,searchweb201603_6&btsid=24595642-06bc-4553-b4b2-2c571ea87172)
Both of these descriptions say "Free shipping" but it also includes the shipping costs on the page.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on July 24, 2016, 05:01:54 pm
It depends where you are. If you are in the United States as your flag indicates, there are no free shipping options. But if you live else where, there may be free shipping options. Just to double check I changed my country to 'Russian Federation' on the site, and there were 2 free shipping options, as well as 2 faster paid shipping options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 24, 2016, 06:05:48 pm
something very important.

dont follow the advice of any assholes with video's, blogs or websites that say to re-write the firmware in a chinese USBasp.

i'm getting sick of it, the firmware in the chinese programmers is newer and better than the old 2011 firmware.
the error message you see is simply because your trying to set the timing on firmware that auto-calibrates and does not need to be set - ignore the SCK error!
Title: Re: $20 LCR ESR Transistor checker project
Post by: maxcombor on July 24, 2016, 06:15:05 pm
For all beginners simpliest way is serial port programming with only 3 resistors and one jumper for reset pin, copy downloaded files in root c:\ (TransistorTester.hex and TransistorTester.eep ) I`m soldered pin header  from downside direct on atmega pins and program in three seconds .

In avrdude.conf change inverted reset to non-inverted

reset = 3

and with next 3 comands programm atmega

avrdude -p ATMEGA328P -c ponyser -P COM1  -U flash:w:"C:\TransistorTester.hex":i

avrdude -p ATMEGA328P -c ponyser -P COM1  -U eeprom:w:"C:\TransistorTester.eep":i

avrdude -p ATMEGA328P -c ponyser -P COM1 -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

Fusebits are for default 8Mhz version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 24, 2016, 06:33:32 pm
you forgot to set the fusebytes
 :o
Title: Re: $20 LCR ESR Transistor checker project
Post by: maxcombor on July 24, 2016, 08:40:09 pm
STJ , funny but on all 3 my peaces fuses and eeprom are programmed , but without flash . Corected commands in previous post.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 24, 2016, 09:13:04 pm
ah yes, but some people are changing the chip.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on July 24, 2016, 11:16:45 pm
It depends where you are. If you are in the United States as your flag indicates, there are no free shipping options. But if you live else where, there may be free shipping options. Just to double check I changed my country to 'Russian Federation' on the site, and there were 2 free shipping options, as well as 2 faster paid shipping options.
Then they need to change the description and remove the words "Free Shipping".
Title: Re: $20 LCR ESR Transistor checker project
Post by: maxcombor on July 25, 2016, 12:58:37 pm
User manual and shematic in pdf for mega328_color_kit , thanks bmht for photo. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on July 25, 2016, 01:34:54 pm
@maxcombor
There it was published :)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg972406/#msg972406 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg972406/#msg972406)

Or can be downloaded directly from the seller:
* User Manual (http://115.28.16.44:81/file/4586.pdf)
* Schematic Diagram (http://115.28.16.44:81/file/4586-1.pdf)
* Components (http://115.28.16.44:81/file/4586-2.pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: fitch on July 25, 2016, 07:32:13 pm
Hi all,
Add me to the list of owners.  Got my kit from eBay for $12.99 with free shipping.  Everything seems to work fine.

I have questions on building the firmware:

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on July 25, 2016, 09:45:04 pm
It depends where you are. If you are in the United States as your flag indicates, there are no free shipping options. But if you live else where, there may be free shipping options. Just to double check I changed my country to 'Russian Federation' on the site, and there were 2 free shipping options, as well as 2 faster paid shipping options.
Then they need to change the description and remove the words "Free Shipping".
Just because you are American?

I also don't get the free shipping option in the UK, but really - 11 pence for shipping from China? It's as good as free.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on July 26, 2016, 01:21:15 am
It depends where you are. If you are in the United States as your flag indicates, there are no free shipping options. But if you live else where, there may be free shipping options. Just to double check I changed my country to 'Russian Federation' on the site, and there were 2 free shipping options, as well as 2 faster paid shipping options.
Then they need to change the description and remove the words "Free Shipping".
Just because you are American?

I also don't get the free shipping option in the UK, but really - 11 pence for shipping from China? It's as good as free.
No, just because it is not truthful writing that it is free shipping when it isn't.

You are the first Brit I have interacted with who exhibited a very poor attitude.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on July 26, 2016, 06:16:35 am
Free shipping (for example) :)
http://www.ebay.com/itm/141666336329 (http://www.ebay.com/itm/141666336329)
http://www.ebay.com/itm/141975823733 (http://www.ebay.com/itm/141975823733)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on July 26, 2016, 07:09:00 am
Is the github repository up do date with regard to the k firmware?

GitHub repository is up do date.

I see that there are some version issues with avr-gcc.  I have a Window10 machine which is my first choice to build on, but I can also set up Linux in a VM.  Can I build the fw with AVR Studio?  Any way to use the arduino IDE?

To edit the source code and compile the firmware I recommend a use WinAVR (http://winavr.sourceforge.net/) with an updated version of the AVR-GCC (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg825078/#msg825078). After update the AVR-GCC (I recommend to version 4.8.1) is need to use fix of the compilation error ("MSYS-1.0.dll") (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg818096/#msg818096) - applies to Win 8, 8.1 & 10.
Title: Re: $20 LCR ESR Transistor checker project
Post by: fitch on July 26, 2016, 08:40:16 pm
@tom666
Thanks for the info.  I was going to install then update WinAVR, but the installation wanted to muck with my path, I decided I did not trust it.  Instead, I have an Ubuntu 16.04 installation running in a virtual machine, and was able to install gcc-avr and avr-libc.  This works fine, and I don't need to corrupt my Windows 10.

By the way, my tester uses an ATMEGA328P, and even though the gcc-avr installed was 4.9.2, everything built fine and fit inside the part.

Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on July 26, 2016, 09:53:24 pm
What is the age / evolution of this chip , I may have to look through my container of chips to be scraped , mostly older gear , thats why it occurred to me how long its been around ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 28, 2016, 06:54:32 pm
A quick update about running the tester at 20MHz. I've haven't tested every component and function yet, but it's running fine so far. If everything goes well, I'll release the new version in one or two weeks. It has several improvements for the semiconductor detection and a few bug fixes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 29, 2016, 07:47:29 am
Got a problem writing the efuse part, it is givng an error. The command issued is:
avrdude -c usbasp -p m328p -B 4.0 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

avrdude: reading input file "0x04"
avrdude: writing efuse (1 bytes):

Writing |                                                    | 0% 0.00s ***failed;
Writing | ################################################## | 100% 0.04s

avrdude: 1 bytes of efuse written
avrdude: verifying efuse memory against 0x04:
avrdude: load data efuse data from input file 0x04:
avrdude: input file 0x04 contains 1 bytes
avrdude: reading on-chip efuse data:

Reading | ################################################## | 100% 0.00s

avrdude: verifying ...
avrdude: verification error, first mismatch at byte 0x0000
         0xfc != 0x04
avrdude: verification error; content mismatch

avrdude: safemode: efuse changed! Was 4, and is now fc
Would you like this fuse to be changed back? [y/n]

Someone knowing what could be the cause of it?
The programmed 328p chip does however work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 29, 2016, 09:25:22 am
You can ignore that error. It's a known issue with an incorrect definition in avrdude's configuration file. From Karl-Heinz' documentation:
Quote
The program avrdude probably reports a error for setting the extended fuse efuse. The reading of unused
fuse bits is specified as ”1” for the ATmega, but the avrdude program mask the unused bits, so that
it expect a ”0” for all unused bits. Normally the efuse should be set to 0xfc, but avrdude read back
0x04 with the mask. You can change the file avrdude.conf to change the behaviour of avrdude or
you can set the efuse to 0x04.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 29, 2016, 02:24:28 pm
@Madires: Thank you very much for the explanation!
Title: Re: $20 LCR ESR Transistor checker project (separate frequency ports?)
Post by: ja421 on July 29, 2016, 07:51:59 pm
I have read thru most of the posts but didn't see / find an answer.
I have noticed that some of the ebay clones of the project have separate ports for frequency in/out and battery voltage test.
From my limited understanding, the regular ones can do these thru the regular zip socket using pins #1 & #2 (and selecting the proper menu item)

Is there a technical benefit to getting one with separate ports vs one that doesn't ?
For simple comparison, here's two links:

This has separate ports (bottom is frequency out and voltage test; top is frequency in) (http://"http://www.ebay.com/itm/2016-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator-/252405848389?var=&hash=item3ac48f9945:m:mu1rbjdppniuB3xJC5FDFOg")
This one re-uses it's regular pins for freq in/out, and voltage test (http://"http://www.ebay.com/itm/2016-GM328-transistor-tester-ESR-frequency-LCR-Diode-Capacitor-meter-squarer-DIY-/231968645451?hash=item360268a14b:g:o6kAAOSwmtJXU~Hd")

Just curious if one is better/more robust than the other...
Title: Re: $20 LCR ESR Transistor checker project (separate frequency ports?)
Post by: hapless on July 30, 2016, 12:36:43 am
Normally, they can't do that through the 1-2-3 socket. From the page for the one without frequency measurement input: "B. extensions (via menu selection, and the user may want to add a few components, suitable for DIY)." Read: It won't work until you add those "few components."

BTW, you may want to fix your links.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 30, 2016, 01:19:39 am
damn those chinese bastards, those sellers are calling the TFT kit a "GM328" or "GM328A"

that's going to lead to people flashing them with the wrong firmware!
i call them the "2578AY-AT" - it's printed on them!
Title: Re: $20 LCR ESR Transistor checker project
Post by: ja421 on July 30, 2016, 01:27:42 am
Thanks.  I guess I will try the 'real' version (I was having a problem finding a pcb, but I'll keep looking).
Appreciate your time & thoughts.

Any chance there is one ebay (or other) version that is considered 'better'?  I know better is subjective, but I'm going to be traveling in a small RV and am really looking for as few kit items as possible, so handling more options (ie: frequency counting/generation) is a plus...   
I have noticed a lot don't have ISP, and some have unsocketed MPU's ; which makes updating firmware harder, but not impossible... (I have read that some lock the memory?)

Anyway -- thanks. I'll keep looking around.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 30, 2016, 10:39:39 am
The output of the PWM or squarewave signal runs via the standard probe pins. Additional probe pins are required for the Zener test and the frequency counter. There are two versions of the frequency counter. A simple one with a few parts (ATmega328) and a more complex one with a prescaler and oscillator for crystals (ATmega644). Both are depicted in Karl-Heinz' documentation.

If you like to update the tester, you'll need the current k or m-firmware. The Chinese clone vendors don't provide any updates, AFAIK. And some lock the MCUs to prevent others to read the firmware. It's  |O, since the whole project is OSHW. Anyway, it's handy to have a copy of the original firmware, just in case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on July 30, 2016, 08:58:47 pm
There seems to be a million variations of this project, I already have the 2x16 one but am looking for better firmware.  Considering a graphic one but which one is best? Thanks  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ja421 on July 30, 2016, 09:32:14 pm
I had used a fish8840 version that worked well until I ran over it with a chair.  I have read some negative things about them, but it seemed to work ok for me. (I was able to update the firmware w/o issue)

My current one is a "gm328a" version from ezm electronics studio... All surface mount.  it, too, worked well for me, until...
I don't know if it was due to upgrading the firmware to current version, or the hardware, but I tested a diode that looked similar to one that was broken on a pcb (hoping to gleam some info to buy a similar diode) - however, I was able to test it once and got a reading; but after that, the diode failed all tests, using a dmm it registered as about a 1 ohm resistor in both directions... 

(Trashing a diode is another reason I'm looking for a new version...)
Both the versions I had, had the mpu soldered on, but had provisions for an ISP header (but no header) -- as I recall, both headers ended up being on the bottom, so it's not something you want to leave on the tester.  From what I can tell; you want a socketed chip so you can replace it if they locked the firmware... but I am a novice there...
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 30, 2016, 09:39:53 pm
it cant trash a diode, it cant supply enough current.
it can only just light an led.

you dont replace a locked chip btw, you erase the lock bits before you program it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ja421 on July 30, 2016, 09:49:57 pm
it cant trash a diode, it cant supply enough current.
OK -- so then it was complete coincidence that it was able to test the diode once & then the diode failed -- it's not surprising, I am expecting the board that we're working on to have other components fail as we fix the dead ones...
In that case the fish & gsm versions have worked great, up until I broke it or lost faith in it...

you dont replace a locked chip btw, you erase the lock bits before you program it.
I would have to look it up; but I read one where you needed to use a HV programmer to reset the lock/fuse bits; something not everyone has; but if it's just a matter of rewriting the lock bit, then any version is going to be upgradable...

Sorry I was so off the mark there -- didn't mean to mislead anyone.... thanks for educating me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 31, 2016, 02:02:54 am
no, to erase the lock bits you just send the global erase command.

you only need a high-voltage programmer if you accidentaly set the fusebits to disable the SPI debug port.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hansibull on July 31, 2016, 10:10:42 am
Quote
There seems to be a million variations of this project, I already have the 2x16 one but am looking for better firmware.  Considering a graphic one but which one is best? Thanks  :)

I'm very happy with the transistor tester with a color LCD (http://www.ebay.com/itm/252395864334)! It has a nice enclosure, large rechargeable Li-Ion battery that you can charge with a micro USB cable. It can also measure zener diodes up to 27v, because it has a built-in step-up converter (use the K/A area). It's a winner  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on July 31, 2016, 12:14:40 pm
@hansibull:

Is it possible to upgrade the firmware?
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 31, 2016, 02:55:26 pm
i just built this latest firmware for the TFT COLOUR KIT,
8 & 16MHz builds - enjoy.

BTW, i am refering to this kit as the "AY-AT" because that's printed on the pcb.
be carefull - some chinese bastards are calling them "GM328" and they arent!
Title: Re: $20 LCR ESR Transistor checker project
Post by: ja421 on July 31, 2016, 04:17:43 pm
@STJ -- do you have a link for the pb you bought?  I would rather build my own than buy a whole pre-made unit, but haven't found a pcb source...
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 31, 2016, 05:49:29 pm
@STJ -- do you have a link for the pb you bought?  I would rather build my own than buy a whole pre-made unit, but haven't found a pcb source...

i didnt buy it, i built it for a friend and built the latest firmware for it.
i dont really recomend the colour kit - it's slow and needs more memory.

if you want to build you own,
either get the EZ-Studios GM328r or the banggood kit with a case.
http://www.ebay.co.uk/itm/331873741389 (http://www.ebay.co.uk/itm/331873741389)
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on July 31, 2016, 09:42:09 pm
damn those chinese bastards ...

... some chinese bastards ...

Sorry, but I do not like this! :--
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 31, 2016, 11:57:19 pm
damn those chinese bastards ...

... some chinese bastards ...

Sorry, but I do not like this! :--

it's not because they are chinese - it's because of specific misleading behaviour.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 01, 2016, 05:37:45 am
Despite all this I do not like to use these terms!
Title: Re: $20 LCR ESR Transistor checker project
Post by: jjelec on August 02, 2016, 10:00:17 am
In reply to bmht post:2247
Hello, I built this same unit today and when turned on had exactly the same symptoms as yours(bmth).
I immediately thought that I must have been sent a empty micro.
But after checking all my work discovered that I had put the LED in back to front.*&%.
Got it out put it in the right way, switched on and presto all fixed!!.
I'm very happy with it, works well.
JJ :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on August 03, 2016, 02:34:54 pm
i just built this latest firmware for the TFT COLOUR KIT, 8 & 16MHz builds - enjoy.


Thank you STJ, the only thing I missed in the menu was the Rotary encoder test.  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 03, 2016, 09:37:07 pm
too bad, the extra flash needed for the colour function means sacrifices must be made.
unfortunatly i'v not been able to compile it with the crystal test function no matter how much unimportant stuff i disable  >:(
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 03, 2016, 11:02:53 pm
I'm not saying that it can be crammed into the firmware, but if it can, maybe a different (not necessarily newer) version of build tools will help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 04, 2016, 02:28:54 am
i think i already have the best version - for size.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dwaine on August 04, 2016, 02:41:37 am
@hansibull:

Is it possible to upgrade the firmware?
Mauro

I'm wondering the same thing.  Is it possible?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on August 04, 2016, 05:52:37 pm
i just built this latest firmware for the TFT COLOUR KIT, 8 & 16MHz builds - enjoy.

@STJ:  While testing the various  options in this software, I did see 2 strange errors
in the f-Generator table:  431.0345Hz showing here about 27.6KHz and 529.6610Hz
is showing about 33.9KHz on two different frequency counters. The rest of the
frequency table seems OK. I'm using the 8 MHz version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 04, 2016, 06:46:43 pm
hmm....

i would test that, but i only have one battery right now, so cant power the tester & the 8digit counter simultaniously.
 :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 04, 2016, 06:49:33 pm
o.k. - confirmed with a multimeter - i'll look into it.  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 04, 2016, 08:05:34 pm
fixed.
 :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 05, 2016, 01:35:45 pm
New m-firmware 1.24m:
- Measurement of self-discharge leakage current for caps > 4.7µF.
- Added type detection logic for BJTs with diode on the same substrate.
- Improved leakage current measurement to support currents in the nA range.
  The leakage will be shown for diodes and BJTs, when it's larger than 50nA.
- Improved the display of instrinsic/flyback diodes for transistors to check
  for the proper diode (pins and polarity).
- Fixed an error in the display of a BJT's flyback diode.
- Added a function for searching a specific diode and adapted several
  functions to use the new diode search instead of the old local search.
- Improved detection of diodes to support also Germanium types with very low
  Vf at low currents.
- Fixed problem with LCD_ClearLine(0) for ILI9341 and ST7735.
- Improved detection of depletion mode FETs to exclude Germanium BJTs with
  high leakage current. Added detection of FETs with low I_DSS. Added
  measurement of I_DSS.

The last point in the list is the most interesting feature of the new version. The tester detects problematic JFETs like the PN4171A, 2SK117 or 2SK170 now. And Germanium BJTs with a quite high leakage current shoudn't be identified as JFET anymore.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dwaine on August 06, 2016, 12:00:02 am
Quote
There seems to be a million variations of this project, I already have the 2x16 one but am looking for better firmware.  Considering a graphic one but which one is best? Thanks  :)

I'm very happy with the transistor tester with a color LCD (http://www.ebay.com/itm/252395864334)! It has a nice enclosure, large rechargeable Li-Ion battery that you can charge with a micro USB cable. It can also measure zener diodes up to 27v, because it has a built-in step-up converter (use the K/A area). It's a winner  :D

I just got my TC1 Tester.   Very nice unit.   It's running version 2.12k.  I'm going to open it up and see if there is a header to flash.  It has nice to have the rechargeable battery.

Been reading the pages, what's the latest version for k?

Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 06, 2016, 12:20:05 am
latest is 1.12k SVN r684
and it does NOT support multi-coloured display output.

so you should try to dump the atmel in that unit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dwaine on August 06, 2016, 01:19:49 am
latest is 1.12k SVN r684
and it does NOT support multi-coloured display output.

so you should try to dump the atmel in that unit.

I'll try it and see if I can get a dump
Title: Re: $20 LCR ESR Transistor checker project
Post by: kodi on August 06, 2016, 01:23:24 am
fixed.
 :-+
I assume this banggood kit source is referring to this:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html) ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 06, 2016, 03:08:42 am
yes,
i didnt test it though - i did personally test the other 2, but i obviously arent about to collect lots of testers.  ;D

Title: Re: $20 LCR ESR Transistor checker project
Post by: Dwaine on August 06, 2016, 07:21:32 am
latest is 1.12k SVN r684
and it does NOT support multi-coloured display output.

so you should try to dump the atmel in that unit.

Well I got two hours out of it.   Measured a capacitor and now it won't power up.   That was quick.  I think it's even a record for myself. :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 09, 2016, 03:04:43 pm
Now that more people got the color TFT units and had some time to play with them, how do they compare to the previous models?

From window shopping, what stands out in the new color TFT models to me is the nicer looking screens.  The input protections, DC jack and the extra connectors.  The DC voltage measurement and up to 30v zeners.

But...


Is there one kit that is considered the "best"?  Its going to be my first.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on August 09, 2016, 03:27:09 pm
Not all the newer testers have all the options.

So do not all have the input protection circuit, that is for me a must have.

I have The EZM GM328A and the "Mega328 Color-Kit" models.
Both do a good job.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 09, 2016, 04:17:16 pm

  • Is the slow display a real issue?
if it's your first - you wont really know any better,
if not then it will piss you off pretty fast.
it may be fixed by upgrading the clock from 8 to 16MHz with a new crystal - i will report on that when i get some more crystals.

  • Are you missing features due to Memory limitation?
yes, at the moment you cant enable the crystal / resonator test.
(that test only works if you upgrade the crystal to 16MHz anyway)

  • Delay in software updates or none?
software updates come from people like me and other forum members.

Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 09, 2016, 05:25:40 pm
ok guys I ordered the TFT version.  http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html (http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html)

 Mainly because of having DC jack and whatever protection its got.

stj, thank you for baking the various firmwares. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 09, 2016, 06:24:50 pm
...
  • Delay in software updates or none?
...

I recommend to carefully study the manual (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/?view=tar) (file ttester.pdf) from the official SVN repository (https://www.mikrocontroller.net/svnbrowser/transistortester/). Here you can also download the current k-variant of software by Karl-Heinz Kübbeler (kubi48) (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) and alternative m-variant of software by Markus Reschke (madires) (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/).

For your tester with TFT color display is designed k-firmware in the folder "mega328_color_kit (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/)". Content of this folder (files TransistorTester.hex and TransistorTester.eep) can be used directly for burning to the MCU. If you require any changes to the firmware settings, you can make before compiling the adjustments in the file "Makefile". Of course a lot of useful information can be found in the above-mentioned manuals.

Note
In theory it could work also with m-firmware (by madires) (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg998162/#msg998162) because this software also supports controller ST7735.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 09, 2016, 07:25:23 pm
tom,

Is there a comparison somewhere between k and m variant?  Perhaps I should have made my purchase with software in mind.

I take it if a variant supports my display in source code which you noted I have "ST7735" display, then I can compile it for my display?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 09, 2016, 07:42:50 pm
you can use both versions on any modern hardware.

modern as in using a cpu with atleast 32k flash.
no old ATMEGA8 / 168 hardware :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 10, 2016, 03:17:00 am
you can use both versions on any modern hardware.

modern as in using a cpu with atleast 32k flash.
no old ATMEGA8 / 168 hardware :)

and no multi-colored units?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 10, 2016, 03:43:03 am
K & M both handle tft colour displays.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 10, 2016, 04:10:59 am
I have a question about the VCC measured during self-adjustment of the m version. I measured it as 5.024V with a nicely adjusted DMM and set that in the config file. After the adjustment procedure, it gets set to 5.038V. Where should I look to correct this (i.e, I want the self-adjustment to measure correctly rather than just setting this manually)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: deanflyer on August 10, 2016, 10:37:11 am
I need a cheap ESR tester to test a load of capacitors on a faulty power supply board. This looks like a good option.

There are loads of these chinese units out there. Not bothered about programming (maybe later, just dont have the time at present).

This unit seems okay as its got banana plugs and the zif board you can plug in.

Any comments, or any other units I should be looking at?

eBay auction: #http://www.ebay.co.uk/itm/Portable-MK-328-Transistor-Tester-Diode-Capacitance-LCR-ESR-Meter-PNP-NPN-O04F-/361444775198?hash=item5427c9951e

(http://i.ebayimg.com/images/g/ZOUAAOSwcBhWZP31/s-l500.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 10, 2016, 11:37:45 am
I have a question about the VCC measured during self-adjustment of the m version. I measured it as 5.024V with a nicely adjusted DMM and set that in the config file. After the adjustment procedure, it gets set to 5.038V. Where should I look to correct this (i.e, I want the self-adjustment to measure correctly rather than just setting this manually)?

If you have enabled the external 2.5V reference in config.h, then the value set via UREF_VCC in config.h is adjusted accordingly to the external reference. In this case, measure also the voltage of the 2.5V reference and change UREF_25 in config.h too. Or disable the external reference to prevent the automatic adjustment of UREF_VCC. You might also need to tweak the values a little bit to reach your desired voltage, because the ATmega328 has a resolution of only 4.88mV with Vcc (5V) as reference. Another setting to play
with is ADC_SAMPLES. More samples will improve the measurement, but slow it down at the same time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 10, 2016, 03:33:53 pm
I need a cheap ESR tester to test a load of capacitors on a faulty power supply board. This looks like a good option.

There are loads of these chinese units out there. Not bothered about programming (maybe later, just dont have the time at present).

This unit seems okay as its got banana plugs and the zif board you can plug in.

Any comments, or any other units I should be looking at?
http://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=mk-328&_sacat=0 (http://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=mk-328&_sacat=0)

(http://i.ebayimg.com/images/g/ZOUAAOSwcBhWZP31/s-l500.jpg)

I think this MK-328 is one of the best units I've seen for everyday bench use.  Mega328p chip, three clip leads and nice case with brass inserts.  Looks like it even has input protection.  If you had posted a day sooner I would have bought this one for sure instead of the 328-color tft kit.  A member indman has a folder for mk-328 with teardown pics and few older firmwares https://yadi.sk/d/yW8xa5NJgUo5z (https://yadi.sk/d/yW8xa5NJgUo5z)

All the best.
Title: Re: $20 LCR ESR Transistor checker project
Post by: deanflyer on August 10, 2016, 03:46:35 pm
Cheers Flywheelz,

Unit ordered :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 10, 2016, 05:55:31 pm
If you have enabled the external 2.5V reference in config.h, then the value set via UREF_VCC in config.h is adjusted accordingly to the external reference. In this case, measure also the voltage of the 2.5V reference and change UREF_25 in config.h too. Or disable the external reference to prevent the automatic adjustment of UREF_VCC. You might also need to tweak the values a little bit to reach your desired voltage, because the ATmega328 has a resolution of only 4.88mV with Vcc (5V) as reference. Another setting to play with is ADC_SAMPLES. More samples will improve the measurement, but slow it down at the same time.

That's what puzzles me. I set the voltage of the reference after measuring it, too, so I see no reason for the small but persistent offset. I could adjust it to compensate, of course, but that would be cheating.  :( I tried different numbers of samples, but the default seems good enough. Anything else I could try? By the way, the bandgap offset voltage is also set high, 15mV up from my measured 5mV... possibly related?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 10, 2016, 06:05:55 pm
Seems so. Have you measured Vcc at the AVCC pin of the ATmega?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 10, 2016, 06:27:14 pm
It's connected directly to VCC. Did you mean AREF? Right now I'm getting 1077mV both with my DMM and with the self-adjustment measurement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Harm2k16 on August 10, 2016, 10:09:48 pm
Hi all,
I'amfollowing this topic for quite a while now, but i can't seem to find a solution for my MTester (LCR-T4 NoStripGrid, ATMega328P, 8MHz, FPC-12864B graphical display).
When i bought the unit, the display was buggy. So ordered a new one on eBay and replaced the 328P chip.
...but then what i tried, i can't seem to flash (read: get hold of) the appropriate software or software wich works with this tester.
The only thing i've found is (compiled) firmware on this site:

https://yadi.sk/d/yW8xa5NJgUo5z (https://yadi.sk/d/yW8xa5NJgUo5z)

...but this 8MHz firmware is in the Russian language, don't misunderstand me, i don't have anything against Russian, but i can't simple read it and don't understand it either.
No i have a question for you gentlemen/ladies; does anyone have ready compiled firmware for my/this tester in the English language?

(For clarity, on yadi.sk it's the LCR-T4(T3)NoStripGrid tester with a 8 MHz crystal and no rotary encoder, just a push-button switch.)

Please seeking help with this.
Thank you in advance.

(P.S. I use the "Extreme Burner AVR" from this site: http://extremeelectronics.co.in/avr-tutorials/gui-software-for-usbasp-based-usb-avr-programmers/ (http://extremeelectronics.co.in/avr-tutorials/gui-software-for-usbasp-based-usb-avr-programmers/) in combination with a USBASP hardware from LC-Studio (eBay)).
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 10, 2016, 10:32:31 pm
Could you be more specific about the firmware you tried to use other than the Russian one, and exactly how it didn't work (upside-down screen? immediate shutdown?)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 11, 2016, 12:58:05 am

The only thing i've found is (compiled) firmware on this site:

https://yadi.sk/d/yW8xa5NJgUo5z (https://yadi.sk/d/yW8xa5NJgUo5z)

...but this 8MHz firmware is in the Russian language, don't misunderstand me, i don't have anything against Russian, but i can't simple read it and don't understand it either.

they included the makefile - give me 5 min's
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 11, 2016, 01:11:32 am
T4
Title: Re: $20 LCR ESR Transistor checker project
Post by: jjelec on August 11, 2016, 05:11:09 am
Can someone please tell me the range of the frequency measurement feature.
And the accuracy, and is it affected by standard calibration.
My TFT colour version with 1.12 seems to be way out.
At 455KHz.
 :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 11, 2016, 05:46:30 am
firstly, it's only as good as the cpu clock.
i know some people replace one of the 22pf crystal caps with a variable capacitor and adjust it with a frequency counter.

second, AFAIK it's only good to 4-6MHz with the 8MHz crystal - maybe 10MHz if you have a 16MHz crystal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 11, 2016, 05:51:19 am
It's accurate enough for aligning IF coils, but you will need to really increase the amplitude of the signal somehow. The MCU's pin is likely not going to be sensitive enough. Not to mention that you'd probably be better off with something that can actually generate proper signals instead.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jjelec on August 11, 2016, 06:41:58 am
I was trying to use it to measure(check) output frequency old my old valve(tube) AM RF generator.
 Seems to work OK at IF frequency, but when checked against 3 fairly modern transistor radios, all peaked with
transistor testor showing approx 452KHz instead of 455KHz.
Of course there is a chance that all 3 radios are out, but I don't think so.
Plently of RF level going in, can back the level way down before tester stops sampling.
 I have nothing to calibrate with.
JJ
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 11, 2016, 07:07:05 am
It's not impossible that your tester is off, but I would say that unless one of those radios has a ceramic/SAW 455kHz filter, it's more likely that they are simply not tuned to 455kHz exactly, especially if they were all made on the same factory. They don't have to be.

To give you an idea of how accurate the tester can be out of the box, with no tweaking mine measures 100.0060Hz on a 100.0042Hz signal.

A cellular phone or a computer can generate a fairly accurate tone that you can test your TT's frequency counter with. It may not be too accurate, you should be able to tell if it's off by 3kHz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Harm2k16 on August 11, 2016, 09:18:56 am
T4

Sorry for my late reply (i have no Internet access at work (critical environment)), but the tester seems to be working right now. Thank you so much for taking the time to compile/translate new firmware!
You may ask why replace the 328P chip and not simply erase the thing, well i've tried to read the contents by means of varying the supply voltage (in the hope i would get some sort of "glitch" wich would then allow me to read the contents), but without success the 328P microcontroller didn't survive.
Before this, i've downloaded all firmware on wich i could lay my hands on regarding this T4- tester and tried it, i flashed so many different software that i forgot all those names, mostly got them from Russian sites (with strange names...).

I didn't came accross the original MTtester firmware on the Internet, i guess the Chinese developers didn't "leak" the firmware and/or released it for public.
Finally, here i got the tester from: http://www.aliexpress.com/store/group/Transistor-Tester/1962265_508645019.html?spm=2114.10010108.100008.2.HdoawM (http://www.aliexpress.com/store/group/Transistor-Tester/1962265_508645019.html?spm=2114.10010108.100008.2.HdoawM) they do have nice laser-cut acryllic cases for them.

Thanks again.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Harm2k16 on August 11, 2016, 09:45:23 am
Additional.
FIY: Someone send me the following files just this morning, they also contains different font-types, the DFONT_8x16thin is very nice one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 11, 2016, 02:10:59 pm
i always use 7x12 on monochrome displays because:
Quote
With a font width below 8 more than 16 characters can be shown in one display line.

it's a tool, functionality over style  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: linker3000 on August 11, 2016, 03:04:51 pm
Hi everyone,

I have a board marked EZM Electronics Studio M328_9V_V3.3 2014.10.22 I have flashed a spare 328P with two variants of the firmware with mixed results:

GM328_EZM_v1.12k_r541: Board is hard to turn on. Seems to perform most tests OK but often incorrectly identifies small signal transistors as JFETs

mega328_GM328 from current trunk: Board turns on but ditto with the small signal transistors.

With the original 328P and firmware, the transistors are detected correctly.

Am I using the right firmware and any thoughts on whether it's working as expected or what I can try (i have run a self test on both)

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: elcoma on August 11, 2016, 03:49:45 pm
Hello I have the same tester and found firmware for it on the BADCAPS forum.   (svn 684)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 11, 2016, 04:52:21 pm
Hello I have the same tester and found firmware for it on the BADCAPS forum.   (svn 684)

This should be the one thanks to stj this firmware is from the badcaps forum
Title: Re: $20 LCR ESR Transistor checker project
Post by: elcoma on August 11, 2016, 04:53:52 pm
badcaps forum: SVN 684 software
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 11, 2016, 06:48:19 pm
Hi! Very often there is a confusion with number of revision K-Firmware and M-Firmware. At present the freshest and last revision from Karl-Heinz has number 683! On a photo the example for determination of current issue is shown. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 11, 2016, 07:21:51 pm
all firmwares i build with an SVN reference are "K" firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lordstein on August 11, 2016, 09:45:30 pm
Hello, I bought the transistor tester banggood, also the tl866cs programmer (tl866cs mainly I use it to dump bios
) When buying transistors tester also buy a replacement atmega chip (programmed). I want to upgrade to the latest version of mandires,
I do not currently able to do a dump of the original firmware (possible or manufacturer has blocked reading) it shows the tl866 read but appears blank(ff).

(https://ag8rea-ch3302.files.1drv.com/y3mhWFwpfAx5MUOYQ1yeOdaIWlSVPVTP0-mFILs1JneUB47wSpwoTt8PH7QquHYkbKRA2LBOLc_rM2B_ExabspcsyTUPwjZls6XgnybNQyDvkRHx1zkwr9pPsWYkCLEm5RSHiqB95pQIUjZuZmssXhj6xKHYxVnZ7ZWkWyEPai5gCY?)


(https://cqqg7a-ch3302.files.1drv.com/y3mlfAS3wGG9wBe9se49Hzh6yIamXxbE05EAnCiBM4ezc3S5F7DicrZ7_NBXIjTfKbnETQ3XAFYltxGoAgnmu6Q7HHWXm_Aq5BhFlVAZENYAur_HHy5vMGFS0HIgcAi6K-RseE-RDZO8E5umZAAFDXbS1KBCcL6b_fI0JWJ-s8d-6o?)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 11, 2016, 09:57:57 pm
Hi! Very often there is a confusion with number of revision K-Firmware and M-Firmware. At present the freshest and last revision from Karl-Heinz has number 683! On a photo the example for determination of current issue is shown. :)

Let's try to shed some light on the process ;)

k-firmware: "trunk" is the current version under development (1.12k at the moment), and Karl-Heinz adds features, improvements and bug fixes, while pushing each change to the repository. The repo automatically increases the revision for each submission. When he thinks that it's time for a new version, he archives the current version, moves the archive to "tags" and increases the version in "trunk".

m-firmware: I'm releasing only finished versions and don't submit each change to the repo. But the repo will add a revision to the submission of a new m-firmware. That revison can be simply ignored.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 11, 2016, 11:40:39 pm
all firmwares i build with an SVN reference are "K" firmware.

I think you may have missed indman's point. As I understand, he's wondering how you managed to compile 684 while the latest current version is only 683. My guess is that 684 is a typo, right?

Hello, I bought the transistor tester banggood, also the tl866cs programmer (tl866cs mainly I use it to dump bios
) When buying transistors tester also buy a replacement atmega chip (programmed). I want to upgrade to the latest version of mandires,
I do not currently able to do a dump of the original firmware (possible or manufacturer has blocked reading) it shows the tl866 read but appears blank(ff).

I don't think you'll be able to find any microcontroller sold by banggood that is not locked for reading. You can simply erase whatever is there, then set fuses and flash the new firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 12, 2016, 01:34:55 am
no, it's not a typo.
when you grab the latest files with
Quote
svn checkout svn://mikrocontroller.net/transistortester/Software/trunk

the server gives you the latest version number.
i just ran it now - for you.
and it says:
Quote
Checked out revision 688.

however, some updates are just documentation or bootloaders for people using arduino boards etc.
so 688 is not actually going to be any different from my 684 zip's
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 12, 2016, 02:08:19 am
I see why there's confusion now. Visit this site with a web browser:
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?sortby=rev (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/?sortby=rev)

You will see then why our numbers are different. Both 684 and 688 are for m firmware (688 being the latest, 1.24), and the latest one for k is 683. The server assumes that there's only one project there, which is obviously not the case, so you can't rely on the latest revision number that it provides for you with checkout.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 12, 2016, 10:55:13 am
If you're looking for the latest k-firmware, check the revision of "trunk" at https://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/) and compare that to your local copy. You can do the same for the m-firmware ("Markus") to see if there's anything new, but the revision isn't relevant.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lordstein on August 12, 2016, 04:59:18 pm
all firmwares i build with an SVN reference are "K" firmware.

I think you may have missed indman's point. As I understand, he's wondering how you managed to compile 684 while the latest current version is only 683. My guess is that 684 is a typo, right?

Hello, I bought the transistor tester banggood, also the tl866cs programmer (tl866cs mainly I use it to dump bios
) When buying transistors tester also buy a replacement atmega chip (programmed). I want to upgrade to the latest version of mandires,
I do not currently able to do a dump of the original firmware (possible or manufacturer has blocked reading) it shows the tl866 read but appears blank(ff).

I don't think you'll be able to find any microcontroller sold by banggood that is not locked for reading. You can simply erase whatever is there, then set fuses and flash the new firmware.

ok thanks, i have two atmega 328p i erase both chip and installed the trunks version on chip #1 (no read regulators)  want install mandires on chip 2 but apparently not compiled
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 12, 2016, 05:50:40 pm
Markus provides his firmware as source code. If you tell me what kind of display controller your unit has and whether it has a voltage reference or not, I can compile it for you. Unless... Markus, you don't mind, do you?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 12, 2016, 07:01:26 pm
Be my guest ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 12, 2016, 07:09:24 pm
Thanks!  :)

To speed things up, I made a few assumptions about the tester and compiled the firmware. Unfortunately, I can't test it right now. If this doesn't work right, try to describe the problem in as much detail as you can, and I will adjust parameters and have another go at it.

Edit: There was a problem with icons not being displayed. Go to post 2379 to download a (hopefully) fixed version:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1003295/#msg1003295 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1003295/#msg1003295)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 12, 2016, 08:12:02 pm
If you're looking for the latest k-firmware, check the revision of "trunk" at https://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/) and compare that to your local copy. You can do the same for the m-firmware ("Markus") to see if there's anything new, but the revision isn't relevant.

Dear NickNI - participant of the Russian speaking forum VRTP.RU  created very evident illustrated assistant on use of SVN of an array. I translated this document into English. I think that it will be useful, especially to beginners! https://yadi.sk/d/NrdXtqc_uBCPZ (https://yadi.sk/d/NrdXtqc_uBCPZ)  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 12, 2016, 08:18:23 pm
Thanks for the effort. I suggest also posting a link to the original article as a courtesy to its original author.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 12, 2016, 08:27:11 pm
The original of this document in Russian is here https://drive.google.com/folderview?id=0B4yqyYy2DaakZzBVU3JDSXB6S1E&usp=sharing (https://drive.google.com/folderview?id=0B4yqyYy2DaakZzBVU3JDSXB6S1E&usp=sharing) :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: lordstein on August 12, 2016, 11:14:25 pm
Thanks!  :)

To speed things up, I made a few assumptions about the tester and compiled the firmware. Unfortunately, I can't test it right now. If this doesn't work right, try to describe the problem in as much detail as you can, and I will adjust parameters and have another go at it.

thanks for help me
i installed mandires
the screen show this when i test a kia 7812a (voltage regulator?)

(https://coryug-ch3302.files.1drv.com/y3mnUiURK_nW51kk2Ak0PgAfxz-5oDy9BjTjzhT0YOL-baJlajJDd3J8HhZAko6Sh-3BL7neLKp-uUiQknP-xK5GLq1YO4MHidOJaJhyukp7458cOkj_d1R9syqWe-mNznpg5sbOHk7Q6qYOtabD_dgSWhXS6s5b5CECBPuYxpZUYU?)

this is a a970 pnp transitor ( no diagram of bjt pnp transitor )

(https://dyryug-ch3302.files.1drv.com/y3mZOtYumwBOBlZXmHJ7EfPHdcFOxvRGqmRcYkD81bo70n7QR5KuBCLVwxvxOWi1QUvgO0FFOjnxHJVkczc_SoeOEGYRazR8yJ-jrMdRu3fl5NzRs2__neV34ci6URHz6oniPFm0KhNuU6JBa6SB2wdOFmkQYDc8PJkkHakbjG341c? width="256" height="144")

since i dont know which screen i have, i upload a photo from it, where i can search the type of screen?

(https://cyryug-ch3302.files.1drv.com/y3m63NLdQx0nEJcEyG-jDOQ93_bjNWW4JBT4Pw2O-GuP8HkLR6oP1RtF8Rfi3GcfhFQ4SBII-K3SHEE4kNODDUxMGCDPotAxeLRzZhlmVbzqjjvKJeYnP-9oPC4LXM6PFknoQymCpnbo9hCBa94zY8oca-6eJwRJMfP0I5aTQzrmfk?)

i used the same efuse config that i used for trunks firmware
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 13, 2016, 12:03:34 am
Yes, the tester can't correctly identify integrated circuits, including voltage regulators. This is normal.

As for the lack of icons... I think you found a small bug.

Code: (diff) [Select]
518c518
< #if defined (SYMBOLS_24X24_V) || defined (SYMBOLS_24X24_H) || defined (SYMBOLS_32X32_H)
---
> #if defined (SYMBOLS_24X24_VP) || defined (SYMBOLS_24X24_H) || defined (SYMBOLS_32X32_H)

Try the file that I've attached now.

Edit: Your screen's controller is ST7565 with SPI interface. I know that because that's what I compiled into the firmware, and it obviously worked.

Edit 2: Delay set to 5 seconds rather than 3, default contrast is now 5 and the encoder should work better thanks to a post (2396) by mauroh.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 13, 2016, 11:07:09 am
Yes, he did. Thanks for the report and bugfix!
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 13, 2016, 02:40:38 pm
Yes, the tester can't correctly identify integrated circuits, including voltage regulators. This is normal.

As for the lack of icons... I think you found a small bug.

Code: (diff) [Select]
518c518
< #if defined (SYMBOLS_24X24_V) || defined (SYMBOLS_24X24_H) || defined (SYMBOLS_32X32_H)
---
> #if defined (SYMBOLS_24X24_VP) || defined (SYMBOLS_24X24_H) || defined (SYMBOLS_32X32_H)

Try the file that I've attached now.

Edit: Your screen's controller is ST7565 with SPI interface. I know that because that's what I compiled into the firmware, and it obviously worked.


while it's nice that you included the license in that zip, you *should* have also included any files you changed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 13, 2016, 04:05:54 pm
Yes, he did. Thanks for the report and bugfix!

You're most welcome. :)

while it's nice that you included the license in that zip, you *should* have also included any files you changed.

I should have put the filename in the previous post (thought I did, but apparently was in too much of a hurry), but other than that, no, I should not have included the changed file in my archive. Markus will do that when he changes it in the SVN. I posted the simple change that I made, and it is absolutely trivial to make it for anyone who's looking at the source. Someone who cares only about the stuff that comes out after it was compiled should be able to read the license, the instructions, and have the necessary files to complete the task they set out to perform, that is, to flash the microcontroller. When you download a game, do you really want it to contain all the source code files that the last reviewer had changed? All you care about is the executable and any files that make it run. This is no different.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 13, 2016, 07:15:58 pm
your missing the point.
including any changed files helps people understand hardware they may not have in front of them.

and try to remember that this is OPEN SOURCE.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 13, 2016, 08:06:26 pm
How am I missing the point? The source is freely available, and my patch is out there for everyone to see. Including the file in the archive would thus have been redundant and also confusing for someone who had downloaded it just to flash it. I should also mention that if I were to submit this change as a file, it would not be the changed file, but the very text you see in my post inside a .diff file. So I guess I don't see your point. Do elaborate on what goes against someone's learning or open source in the way I did it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on August 13, 2016, 09:06:44 pm
STJ,
FWIW, I think Hapless has the correct approach for Open Source software. He passed out a simple correction that anyone could make to their own files. If they chaged it, they would understand the change.

On the other hand you released a "version" called svn 684 but only included two files. This version is in a version system that doesn't exist except on your machine.

As best I can tell comparing to my SVN copy, these files are NOT the same as those in the k version repository and if I incorporate them into my svn, I potentially create a problem down the road. If Karl-Heinz modifies his version of these two files I would lose your changes and may not know why. If he doesn't change them but references something that you have now removed from those files, my build would fail. Either way, I would probably report it as a bug when, in fact, it was the result of changes from you that I mistakenly thought were part of the same branch.

Open Source means the source is available and modifiable by anyone. You are free to create a proper branch and continue maintaining and distributing it but if you are going to modify Karl-Heinz version of the code it would be far better if you had done it as Hapless did (the author was informed of the bug and left up to him when to include it in his official release) or JUST distributed the recompiled versions that would get replaced the next time a build is done.

This, of course, is just my opinion, but while you may be an experienced programmer, you have obviously never dealt with serious software maintenance and distribution.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 13, 2016, 10:03:48 pm
the files i zipped are clearly marked "changed files"
of course they dont match the svn - you need to diff/compare them.
HOWEVER.
they do show people the correct settings for the hardware.
because the makefiles hosted by karl are generic and pretty bad.
(being polite about it)

they have badly configured contrast, incorrect included features etc.
i go to a lot of trouble to finetune those makefiles - display contrast, voltdrop from the battery etc.
it's only right that i share them afterwards for others to use.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 13, 2016, 11:35:43 pm
I don't know whether to laugh or cry, but it sure feels like I'm getting a degree in psychology or something of the sort here.  :o What I'm trying to say is that I have finally puzzled out what this is about. Basically, the idea is to include the changes done to the configuration file to match the hardware (unless I missed something again). I don't mind doing that, but don't see the point right now anyway. That's because I used mostly the defaults and simply enabled some of the features that I thought the hardware has. There was no tweaking, since I had no way of knowing at the time which exact tester the person asking for the firmware had. I think it would be a better idea for owners of different devices to share their specs and measured voltages and resistances, best contrast settings, and so on, so that tweaking any firmware (hey, who says there have to be only two, right?) to support those testers would be more straightforward. A forum is not the best place for such a collection of data, but a website with a database... why not?

Any takers?  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 14, 2016, 04:11:53 am
the hard part is getting people to answer questions like "what's the best contrast value".
they cant be bothered repying once the firmware works!
 >:(

then there is the curse of the devil's operating system - Win10

i have been getting a number of people recently who couldnt program the tester with AVRdude.
it looks like win10 cuts the command-line buffer short, possibly terminating it at a back-slash.

i have to get win10 victims to program the flash,eeprom and fuses in 3 seperate passes!  >:(
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on August 15, 2016, 02:15:52 pm
I bought the Banggood version:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)
( 'Orignal'   :-DD  Hiland DIY M12864 Graphics ... ) . I understand it's the 12864 LCD module.
I want to update its firmware.

- Can it be found in the "trunk" (k firmware)  ST7565 ?
Which of them  mega328_st7565, mega328_st7565_kit, mega328_T3_T4_st7565, mega328_T5_st7565, mega328_wei_st7565?

- Can it be found in the "Markus" (m firmware) ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on August 15, 2016, 04:40:41 pm
The Banggood tester firmware you can use:

https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=245484

See https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg997651/#msg997651
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on August 15, 2016, 05:32:17 pm
The Banggood tester firmware you can use:

https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=245484

See https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg997651/#msg997651
Thanks !
But I still wonder whether in the repository there's a 'k' ("trunk") or 'm' ("Markus") version for the 12864 LCD ?
( and whether the 12864 is the ST7565 ? )
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on August 15, 2016, 06:58:57 pm
The correct repository for the DIY Banggood tester is mega328_st7565_kit for the k version

For the m version you need to compile it by yourself changing the proper lines on the config file

I posted the compiled 1.23m few post back and here you can find also the latest 1.24m

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1003108/#msg1003108 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1003108/#msg1003108)


Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Harm2k16 on August 15, 2016, 07:58:03 pm
Hi STJ,
Me again... ;)
I'am trying to compile (how it's done, i'am an absolute n00b with this) the .hex and .eep files for my lcr-t4 tester with your original un-modified Makefile.
I've installed WinAVR (latest) and set-up the directories (maps) on my hdd with the files from the SVN- repository (downloaded the whole tarball).
It seems to be working, at least i see no errors, had to replace the msys-1.0 file in the utils\bin directory of winavr.

...but my output TransistorTester.hex- file is 103kB in size! Your files are a .hex- file of 83kB (8MHz version) and 89kB (16MHz version) in size.
(I've used your supplied Makefile to compile.)
How is this possible?
Any help, comments, e.t.c. is -dearly- appreciated.
TIA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on August 15, 2016, 08:21:45 pm
For the m version you need to compile it by yourself changing the proper lines on the config file
 ... here you can find also the latest 1.24m
Mauro
Many thanks Mauroh.
I think he fixed some display issue version v2 :

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1003295/#msg1003295 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1003295/#msg1003295)

Still, What are proper config.h lines to change to make it (and future repository 'm' versions) work with the banggood LCR ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 15, 2016, 08:57:46 pm
[...]I think he fixed some display issue version v2[...]

Yes, he thinks he did so, too. He can't be sure because of the lack of feedback, but, as stj mentioned a few posts ago, when something works, people tend to just grab it and disappear.  :D

[...]Still, What are proper config.h lines to change to make it (and future repository 'm' versions) work with the banggood LCR ?

The  configuration in config.h is not set in stone for any tester. In config_328.h, you need to set the display driver to
Code: (C) [Select]
/*
 *  M12864 DIY Transistor Tester
 *  - ST7565 display
 *  - rotary encoder at PD1/3
 */
by commenting out the corresponding #if 0 and #endif and uncommenting the currently commented ones, and in config.h you can choose some of the options that you want to be enabled, again, by uncommenting the corresponding #define statements. You'll want the encoder, the voltage reference, and the frequency counter because that is what the hardware is designed with, the rest is up to you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on August 15, 2016, 09:59:35 pm
List of all changes you need to make on the config.h to have the m-firmware working correctly with M12684 DIY Kit


Config.h Changes to work with M12684 DIY KIT (Banggood)

Section:
/*
 *  M12864 DIY Transistor Tester
 *  - ST7565 display
 *  - rotary encoder at PD1/3
 */
Uncomment entire secion and comment other LCD sections

Comment the following line to:
//#define LCD_OFFSET_X

Change the following line to:
//#define LCD_OFFSET_X
#define LCD_CONTRAST     5 


Section:
/* **********************************
 *   Hardware options
 * ********************************** */
Uncomment
#define HW_ENCODER
#define HW_REF25

This should be already
#define UREF_25           2495 //Tipical output of TL431AA (you shuld measure it?)


Section:
/* **********************************
 *   port and pin assignments
 * ********************************** */
Change to
#define ENCODER_A        PD1       /* rotary encoder A signal */

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 15, 2016, 10:08:40 pm
Hi STJ,
Me again... ;)
I'am trying to compile (how it's done, i'am an absolute n00b with this) the .hex and .eep files for my lcr-t4 tester with your original un-modified Makefile.
I've installed WinAVR (latest) and set-up the directories (maps) on my hdd with the files from the SVN- repository (downloaded the whole tarball).
It seems to be working, at least i see no errors, had to replace the msys-1.0 file in the utils\bin directory of winavr.

...but my output TransistorTester.hex- file is 103kB in size! Your files are a .hex- file of 83kB (8MHz version) and 89kB (16MHz version) in size.
(I've used your supplied Makefile to compile.)
How is this possible?
Any help, comments, e.t.c. is -dearly- appreciated.
TIA.

newer versions of gcc make larger files :(
the answer is to overwrite gcc with a slightly older version.
i use the one bundled with the ARDUINO IDE.
https://www.arduino.cc/download_handler.php?f=/arduino-1.6.10-windows.zip (https://www.arduino.cc/download_handler.php?f=/arduino-1.6.10-windows.zip)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 15, 2016, 10:53:05 pm
[...]
Section:
/* **********************************
 *   port and pin assignments
 * ********************************** */
Change to
#define ENCODER_A        PD1       /* rotary encoder A signal */

Mauro

Thanks, don't know how I missed that one. Corrected.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on August 16, 2016, 05:31:17 am
Mauroh,
Excellent ! - That's exactly what I needed.

One wonder though:
'hapless' says uncomment:
================
/*
 *  M12864 DIY Transistor Tester
 *  - ST7565 display
 *  - rotary encoder at PD1/3
 */

while mauroh says uncomment:
===================
/*
 *  M12864 DIY Transistor Tester
 *  - ST7585 display
 *  - rotary encoder at PD1/3
 */

What gives ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 16, 2016, 06:12:37 am
ST7565

there is no ST7585
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on August 16, 2016, 08:51:28 am
ST7565

there is no ST7585
Yes, there is. It's a 66x102 matrix LCD
https://www.crystalfontz.com/controllers/Sitronix/ST7585/306 (https://www.crystalfontz.com/controllers/Sitronix/ST7585/306)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on August 16, 2016, 09:47:12 am
Is it just a typo in my message, I will correct it. The ST7565 is the correct display for the BGDIY M12864.

My list is correct, but it actually refer to the 1.22m version.
For the 1.23m 1.24m you need to modify also the config_328.h where the LCD section is located now

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on August 16, 2016, 05:32:04 pm
FYI - for the 'banggood' version, the LCD display part # is JLX12864G-378

For whoever wants the datasheet - the manufacture (JLX) site:
http://jlxlcd.cn/china/productshow.asp?nClass=97&PClass=0&ID=280 (http://jlxlcd.cn/china/productshow.asp?nClass=97&PClass=0&ID=280)
(bottom of page)

JLX12864G-378-PC (with Chinese character library)
JLX12864G-378-PN (without Chinese character library)

HW Timing & Code examples included.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Harm2k16 on August 16, 2016, 07:14:25 pm
stj, thank you again! :)
I'll go on experimenting with this.
TY
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 18, 2016, 09:35:25 pm
Please, I need help.

I have put together this kit from http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.93.OBbTox (http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.93.OBbTox)  I had to solder the three protection smd parts myself.  Kit does not include test capacitor.

With 9v batt plugged in DC jack and encoder pressed down, there is 235mA draw from batt.  The T3 labeled 9012 gets hot  :-//.  0 volts on socket pin 7.  In circuit the 9012 and two 9014 transistors test good.  The 5v reg 7550A-1 shows shows some voltage drops on every pin in both ways.

I have dis-soldered the LED and surge suppressor but no help.

Any ideas?

Update:

Thanks to stj for pointing it out, I soldered the SRV05-05 front to back.  Once removed device worked!
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 18, 2016, 10:53:02 pm
@flywheelz:
This is probably caused by a short circuit at the output of the 7550. This may be a short circuit on the PCB, defective capacitor or damaged the 5V stabilizer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 18, 2016, 11:04:58 pm
I've pulled the 7550 and connected in directly to 9v bat and it puts out 5.05 volts.  Also, without 7550 the 9012 is runs cool and switches on providing 9v to VIN for 7550.

Where is 5V stabilizer?  I don't have schematic from seller but looking at ttester.pdf page 10.

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 18, 2016, 11:30:57 pm
did you test it with no atmel or display?

btw, i see you damaged the atmel socket! - i would have used a turned-pin type.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 19, 2016, 12:07:34 am
did you test it with no atmel or display?

btw, i see you damaged the atmel socket! - i would have used a turned-pin type.

No atmel or display testing for 5v on pin 7 first.

Yes one pin 22 was violated by dvm probe, I will bend it back with a needle  :-+  But the LED wasn't so lucky, ended up with one leg  :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 19, 2016, 12:56:07 am
first, check the resistance between ground and the input and output pins of the regulator - to see which side the mystery load is on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 19, 2016, 12:58:12 am
and make sure the 6pin diode-pack is on the right way!
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 19, 2016, 05:10:02 am
first, check the resistance between ground and the input and output pins of the regulator - to see which side the mystery load is on.

With 7550 removed - GND to Vout 20k ohms; GND to Vin 13.29k ohms.

and make sure the 6pin diode-pack is on the right way!

I can't make out any writings on 6 pin turd.  On the pcb I saw a white dot, I took it as pin 1 and on one side of the brick there is a small tab sticking out, I took it as pin 1. 

Is it on backwards?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 19, 2016, 05:38:20 am
@stj, I think you nailed it.  I can barely make out scratched "| VO5" with one eye and tongue at a right angle and that would mean I put it front to back.  I will have more time Fri evening and will try to remove the diodes pack and put 5v reg back.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 19, 2016, 06:17:36 am
all the kits i have seen, the SMD stuff was already fitted.
was yours different?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on August 19, 2016, 06:34:22 am
Where is 5V stabilizer?  I don't have schematic from seller but looking at ttester.pdf page 10.

Schematic from seller:
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 19, 2016, 03:04:12 pm
@stj, yes,  my kit came with smd parts unpopulated.  Link to seller and picture of what I got few posts back.

@tom, thank you. It matches except for my kit has no input reverse protection diode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 19, 2016, 03:28:18 pm
Does it matter which way I place the suppressor AK1521 diode? I remember flipping a coin when putting it on due to lack of markings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 19, 2016, 04:17:17 pm
Does it matter which way I place the suppressor AK1521 diode? I remember flipping a coin when putting it on due to lack of markings.

in stj post 6 post up theres a good picture you can zoom in on it looks like the part may have a white line/band on that goes towards the top of the tester
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 20, 2016, 12:06:27 am
We've made some progress!

The short was caused by the 6-pin diodes chip I've soldered incorrectly.  Once I removed it the tester is showing some life.  Thank you stj for pointing that out.

If I press in encoder for a second, the screen flashes white.

If I press and hold encoder, I see in green text:
Then it goes to:

Then:

When I let go, unit turns off.

What now??? :-//  Its like something atmel not latching something to run.

Do the MC5 6-pin chip and AK1521 suppressor required to run?

I made sure pin 22 I damage is ok.  But looking the board, pin 22 is not connected to GND as schematic shows.

Update:
Other thing its missing is the LED and that looks like its required for the current path for s9014.  Is it correct?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 20, 2016, 01:01:26 am
look at the schematic, there is a transistor or 2 that hold the power on.

and you DO need the led - it's not just for lighting up.
no led will cause this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 20, 2016, 01:22:01 am
I don't have any LEDs at the moment.  So I've soldered in a 3.3v zener the normal way instead of LED and now the unit stays on  :phew:  I think the original led had was1.8v forward voltage drop.  Do I need exact LED as original?

Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on August 20, 2016, 01:52:04 am
@stj: Good call on that TVS diode orientation.

@flywheelz: The LED is not critical. You could even leave the zener in but as the Vf is only about 0.65V, your current through that path will be higher (about 3-5 mA). I would suggest putting in any 3mm or 5mm red, wht, green LED. It is nice to have an indication that the device is on although it should power off after a timeout and you can also see the display.

Graham
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 20, 2016, 02:21:11 am
@stj: Good call on that TVS diode orientation.

@flywheelz: The LED is not critical. You could even leave the zener in but as the Vf is only about 0.65V, your current through that path will be higher (about 3-5 mA). I would suggest putting in any 3mm or 5mm red, wht, green LED. It is nice to have an indication that the device is on although it should power off after a timeout and you can also see the display.

Graham

I think the zener might be causing a problem.  The button is not registering after power-up.  I can't enter calib.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 20, 2016, 03:23:33 am
dont you have anything in the junk pile with an led?
smd would be nice - it wouldnt be sticking up so much.
i do like smd led's :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 20, 2016, 04:44:03 am
dont you have anything in the junk pile with an led?
smd would be nice - it wouldnt be sticking up so much.
i do like smd led's :)

I probably do but the first LEDs I saw staring at me that I could borrow was from the top board of B3606 that I blew up a week ago.  I plan to fix it too, waiting for parts.

I can not believe how hard it was to clean out the holes for donor LED to fit  :wtf:.  I think I would rather do smd over through hole any day of the week.

Anyways, once LED was in place the encoder button started working!  :-+

I want to thank everyone from the bottom of my heart that helped me with this ordeal, my first DIY kit.   :-+ :-+  And especially those that starred this project and keep on improving it.  :clap:

Check this out!  You can welcome me to the transistor tester family now, finally.  :popcorn:
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 20, 2016, 04:51:26 am
i hope you intend to put those protection diodes back!  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 20, 2016, 06:06:24 am
i hope you intend to put those protection diodes back!  ;D

I still have the AK1521 suppressor that I will put back but the the little 6 legged bastard that was the cause of all this ran off somewhere.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mpavlov on August 20, 2016, 03:53:08 pm
Does any one have the schematic of this version 
 http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

I received the kit but the seller did not provide schematic, BOM or instruction how to build it  :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: mpavlov on August 20, 2016, 05:27:12 pm
I received the schematic from the seller of the kit the problem is solved  :)!
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 20, 2016, 06:31:45 pm
Does any one have the schematic of this version 
 http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

I received the kit but the seller did not provide schematic, BOM or instruction how to build it  :(

Thanks to stj for his help heres the list i used
r1 - 680r sensing circuit
r2 - 470k sensing circuit
r3 - 680r sensing circuit
r4 - 470k sensing circuit
r5 - 680r sensing circuit
r6 - 470k sensing circuit
r7 - 10k reset pullup
r8 - 33k power control
r9 - 3k3 power control
r10 - 27k
r11 - 100k (says r1 but is next to r10)
r12 - 10k voltage divider for battery sense
r13 - 3k3 voltage divider for battery sense
r14 - 560r display related - led current limit
r15 - 27k
r16 - 0r jumper for AVCC
r17 - 2k2 from tl431 to vcc
r18 - 1k rotary encoder current limit
r19 - 1k rotary encoder current limit
r20 - 10k rotary encoder pullup
r21 - 10k rotary encoder pullup
r22 - 470r frequency input dropper
r23 - 10k frequency input voltage divider
r24 - 10k frequency input voltage divider

rv1 - 10k preset frequency input voltage divider

u3 = tl431

q1 - 4673 (bc557c)
q2 - c945 (bc547)
q3 - c945 (bc547)

c1 - 22pf for crystal
c2 - 22pf for crystal
c3 - 100nf
c4 - 10nf
c5 - 100uf 25v
c6 - 100uf 25v
c7 - 100nf
c8 - 100nf
c9 - 100nf frequency input DC blocker
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 20, 2016, 06:59:36 pm
In case anyone else gets this Color TFT kit from http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.93.7jYDZE (http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.93.7jYDZE)

The seller sent me the schematic, parts list and instruction in English.  I have attached them to this post: #2405 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1007286/#msg1007286)

Reading the instruction, it says the Transient Voltage Suppressors?TVS? P6KE6V8 has no polarity and can be soldered either way.  The component I've received has no markings.

As for SRV05-4 6-pin diodes array, if you can't read the markings, you will able to identify pin numbering using DMV diode test mode.  Put black lead on middle pin and red on any other pin except the other middle pin and you should see 1.413 Fv drop.  If correct, then black lead is pin #2 and pin #1 to the left of it.  If you didn't get 1.413 Fv drop, then the black lead is pin #5.  Across from #5 is #2 and #1 to the right it. 

The instruction say you could leave out the three SMD components if too hard to solder  :-DD.

The kit PCB is of high quality.  All the components worked.  Only negative is the P6KE6V8 has no markings and SRV05-05 has barely partial marking, if you put this on wrong, unit will not work and 9012 transistor will get hot when button pressed in, credit: stj.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mpavlov on August 20, 2016, 08:12:47 pm
Next problem where I can find the last firmware for the EZM328(GM328R)transistor tester kit ?  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 20, 2016, 08:24:26 pm
Next problem where I can find the last firmware for the EZM328(GM328R)transistor tester kit ?  |O

The one that worked on mine is what stj did for me.

EDIT! see below message i posted a wrong link sorry
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 20, 2016, 09:12:09 pm
no that's the buggy one - look back a page or 2 for the v2
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 20, 2016, 09:22:34 pm
no that's the buggy one - look back a page or 2 for the v2
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 20, 2016, 10:53:57 pm
dont you have anything in the junk pile with an led?
smd would be nice - it wouldnt be sticking up so much.
i do like smd led's :)

I took up the challenge!  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 21, 2016, 12:25:45 am
Nicely done, flywheelz. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 21, 2016, 02:01:36 am
not bad.

btw, did you notice the display needs a couple of thick plastic / paper washers under it to make it sit level on the posts!
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 21, 2016, 04:22:40 am
not bad.

btw, did you notice the display needs a couple of thick plastic / paper washers under it to make it sit level on the posts!

Not sure what you mean  :-// 

To me both pcb are parallel.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 21, 2016, 04:44:39 am
maybe that kit has different headers or spacers from the one here.

btw, what the hell is the microswitch for?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 21, 2016, 05:31:19 am

btw, what the hell is the microswitch for?

 :-DD

I found the encoder push button a bit to stiff hence the microswitch.  Yah its bodge job with hot snott but I like it.  Next I would like to install 3 pin header somewhere so I can hook up test clips.

Its not that there is something wrong with the encoder, its because of muscular dystrophy disability that is causing me to lose strength over time.  I have come to love microswitches  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 21, 2016, 06:27:35 am
put a knob on the encoder.

as for the 3pin socket, get a .1" (2.54mm) 3 pin right-angle socket, and just solder it to the pins of the main socket under the board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 21, 2016, 06:30:43 am
oh yes, get yourself a 16MHz crystal - the AY-AT tester is a slow bastard - it needs a boost :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 21, 2016, 11:28:17 am
BTW, has anyone tried the m-firmware with a 20MHz crystal? I'm curious about any feedback. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Quarlo Klobrigney on August 21, 2016, 03:15:33 pm
So, in the definitive, can the signal generator - freq counter version as seen in the 2nd picture below, (described as a color kit, but is not) use whatever LCD is in the real color tester as shown in the 1st picture, TC1? The TC1 has no rotaly encoder but can test Zener diodes up to 30V. (Like that's a real Textool socket!)
If so, what would be the color LCD part number to be retrofit the 2nd unit, or is there a unit that has a color LCD that I don't know about, that has ALL of the features of both? Secondly is the software able to be used to update either (I guess all 3 versions, bastardized included).
So i.e (e.g.) which one with the most bang for the buck. :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 21, 2016, 04:09:07 pm
you dont know what your talking about.
the kit IS a real colour lcd.

if you mean muliple-colours at the same time - it's just a software difference.
the built unit is probably using custom firmware based on Madires firmware because it can test IR remotes.
the zener tester high-voltage circuit has been around for a pretty long time but not fitted to most boards for safety.
50v+ on an exposed pcb is legally asking for trouble!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Quarlo Klobrigney on August 21, 2016, 04:20:05 pm
"you dont know what your talking about." 
Yes I do. But that's one of us....

"the kit IS a real colour lcd."
I thought that #2 was a monochrome LCD with a dark background and yellow text.

There are others I see with just the green or blue backlit screen with boring black text.
Hence the confusion.
So I ask will the #2 unit be able to display as the #1 unit in multiple colors and the same format? And can the #1 photo be adapted to include the rotary encoder, or is that software prohibitive?
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on August 21, 2016, 04:55:01 pm
BTW, has anyone tried the m-firmware with a 20MHz crystal? I'm curious about any feedback. ;)
Is there a config parameter in the m-firmware that sets the frequency ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 21, 2016, 05:01:48 pm
For 1.24m you just need to set FREQ in the Makefile. And you should have a 20MHz crystal ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 21, 2016, 05:42:53 pm
"you dont know what your talking about." 
Yes I do. But that's one of us....

"the kit IS a real colour lcd."
I thought that #2 was a monochrome LCD with a dark background and yellow text.

There are others I see with just the green or blue backlit screen with boring black text.
Hence the confusion.
So I ask will the #2 unit be able to display as the #1 unit in multiple colors and the same format? And can the #1 photo be adapted to include the rotary encoder, or is that software prohibitive?

the reason the colour kit is just 2 colours (foreground and background) is because the software is designed for a monochrome display.

whoever designed that cased unit tomtop sells has gone to a LOT of trouble with the firmware.
as for adding a rotary encoder, i'm not sure there is much point - i suspect they have left a lot of features out to save memory for the coloured display code.
it uses a different cpu too - atmega324pa
foto's
https://yadi.sk/d/yW8xa5NJgUo5z/??-1/Photo


i can tell you from experience with the kit that i cant enable every feature without running out of flash!
Title: Re: $20 LCR ESR Transistor checker project
Post by: mpavlov on August 22, 2016, 05:09:36 am
This version (GM328x ESR tester (SVN684) - v2(1).zip) of firmware does not works with my kit. I found GM328_EZM_v1.12k_r541.zip from https://www.mikrocontroller.net/topic/345717 (https://www.mikrocontroller.net/topic/345717) works but does not support the rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 22, 2016, 06:24:33 am
this one works - if you cant make it work then your programming it wrong.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 22, 2016, 11:42:05 am
this one works - if you cant make it work then your programming it wrong.
http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
I have just updated my tester to this version 16mhz and all does work fine inc rotary encoder
I used 3 seperate commands
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex

avrdude -c USBasp -p m328p -U eeprom:w:TransistorTester.eep

avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m



Title: Re: $20 LCR ESR Transistor checker project
Post by: alte on August 22, 2016, 01:17:00 pm
Please, I need help.

I have put together this kit from http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.93.OBbTox (http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.93.OBbTox)  I had to solder the three protection smd parts myself.  Kit does not include test capacitor.

With 9v batt plugged in DC jack and encoder pressed down, there is 235mA draw from batt.  The T3 labeled 9012 gets hot  :-//.  0 volts on socket pin 7.  In circuit the 9012 and two 9014 transistors test good.  The 5v reg 7550A-1 shows shows some voltage drops on every pin in both ways.

I have dis-soldered the LED and surge suppressor but no help.

Any ideas?

Update:

Thanks to stj for pointing it out, I soldered the SRV05-05 front to back.  Once removed device worked!

I have this same kit, which came with the SMD components pre-soldered , so it was pretty simple to assemble.
But it does not work  :'(  when I press the encoder button (long or short) the LED flashes briefly and the display backlight flickers, but that's all..
Power is present where you'd expect it, so the regulator works.
So I was thinking maybe the display is defective and I wanted to hook it up to an arduino to test.
I figured it must have a ST7735 driver, but I cannot get the pinout correct, it does not match the only ST7735 from config_328.h.
Does anyone know the pinout of the display ? The schematic matches what I measured, but what function is where..
AT328 pin                  disp.pin
PD0      2   LCD_?      2
PD1      3   LCD_?      3
PD2      4   LCD_?      5
PD3      5   LCD_?      4
PD5      11   LCD_?      6
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 22, 2016, 01:23:00 pm
Please, I need help.

I have put together this kit from http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.93.OBbTox (http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.93.OBbTox)  I had to solder the three protection smd parts myself.  Kit does not include test capacitor.

With 9v batt plugged in DC jack and encoder pressed down, there is 235mA draw from batt.  The T3 labeled 9012 gets hot  :-//.  0 volts on socket pin 7.  In circuit the 9012 and two 9014 transistors test good.  The 5v reg 7550A-1 shows shows some voltage drops on every pin in both ways.

I have dis-soldered the LED and surge suppressor but no help.

Any ideas?

Update:

Thanks to stj for pointing it out, I soldered the SRV05-05 front to back.  Once removed device worked!

I have this same kit, which came with the SMD components pre-soldered , so it was pretty simple to assemble.
But it does not work  :'(  when I press the encoder button (long or short) the LED flashes briefly and the display backlight flickers, but that's all..
Power is present where you'd expect it, so the regulator works.
So I was thinking maybe the display is defective and I wanted to hook it up to an arduino to test.
I figured it must have a ST7735 driver, but I cannot get the pinout correct, it does not match the only ST7735 from config_328.h.
Does anyone know the pinout of the display ? The schematic matches what I measured, but what function is where..
AT328 pin                  disp.pin
PD0      2   LCD_?      2
PD1      3   LCD_?      3
PD2      4   LCD_?      5
PD3      5   LCD_?      4
PD5      11   LCD_?      6
some of these testers are shipped out with no firmware on the atmega ic i myself have had this issue once new firmware installed on the ic all was fine,
Title: Re: $20 LCR ESR Transistor checker project
Post by: alte on August 22, 2016, 01:41:20 pm
Thanks, I could give that a try. I see a lot of firmware's in this thread ;), do you know which one I'd need for this specific tester ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 22, 2016, 02:04:08 pm
im not sure of the exact firmware needed sorry im sure someone will advise one to try shortly
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 22, 2016, 02:09:25 pm
Thanks, I could give that a try. I see a lot of firmware's in this thread ;), do you know which one I'd need for this specific tester ?

On page 93 post 2322 by stj has latest. Try the AY-AT
Title: Re: $20 LCR ESR Transistor checker project
Post by: alte on August 22, 2016, 02:27:13 pm
Thanks, I could give that a try. I see a lot of firmware's in this thread ;), do you know which one I'd need for this specific tester ?

On page 93 post 2322 by stj has latest. Try the AY-AT
Thanks, that seems to be the right one, I have some pictures and AY-AT is printed on het board.
I'm going to give it a try.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 22, 2016, 06:04:05 pm
AY-AT colour tft kit firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mpavlov on August 22, 2016, 06:06:32 pm
Hi vinceroger, stj,

Thank you for detail information, obvious I am doing something wrong when programming the chip with TL866.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 22, 2016, 06:11:53 pm
Hi vinceroger, stj,

Thank you for detail information, obvious I am doing something wrong when programming the chip with TL866.

I have this progrmmer myself try this (a member on this forum helped me with these instructions)
This is the picture with the correct settings for the programmer.
https://www.dropbox.com/s/zqacxby4ayngy2c/Fuses%20on%20TL866A.jpg?dl=0 (https://www.dropbox.com/s/zqacxby4ayngy2c/Fuses%20on%20TL866A.jpg?dl=0)

The only thing you need to do is to load the TransistorTester.hex in the "Code Memory" and the TransistorTester.eep in the "Data Memory"
Pay attention and use always "INTEL HEX" as File Format when you load the files. By default the TransistorTester.eep will be recognized as Binary and you have to change it during loading.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mpavlov on August 22, 2016, 08:31:40 pm
Hi vinceroger,

Thank you very much finally the tester works!   :-+

The problems was that I had programmed the  TransistorTester.eep like binary not hex.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 22, 2016, 08:37:41 pm
Hi vinceroger,

Thank you very much finally the tester works!   :-+

The problems was that I had programmed the  TransistorTester.eep like binary not hex.

Glad you have your tester working and yes i made that mistake too when i first used my programer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kapuchy on August 23, 2016, 10:18:38 am
My version works fine (transistors, capacitors, resistors) but results for small inductors are sometimes weird, for example 128 Mohm or 18 pF instead of 25 uH. There are photos attached. I do not know what is going on. Adjustment procedure: done and save. Shoud I use another power supply, firmware or better linear regulator? Sometimes it helps when I touch GND during "probing" appears.

Firmware version: Markus 1.24m trendy,
Microcontroller: Atmega 328P @ 16 Mhz crystal,
AREF capacitor = 1 nF,
2,5 VDC voltage "reference" = L1117-25C (I know should be LT1004)
Power supply: 12 VDC switched mode + 7805 linear regulator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 23, 2016, 01:54:30 pm
Yes, SMPSUs or DC/DC converters can cause strange results. Please try a linear power supply or an additional LC filter. One issue I've seen so far, is that a cap around 50µF is detected, despite no component is connected, while the tester is powered via a buck converter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 23, 2016, 08:00:36 pm
My version works fine (transistors, capacitors, resistors) but results for small inductors are sometimes weird, for example 128 Mohm or 18 pF instead of 25 uH. There are photos attached. I do not know what is going on. Adjustment procedure: done and save. Shoud I use another power supply, firmware or better linear regulator? Sometimes it helps when I touch GND during "probing" appears.

Firmware version: Markus 1.24m trendy,
Microcontroller: Atmega 328P @ 16 Mhz crystal,
AREF capacitor = 1 nF,
2,5 VDC voltage "reference" = L1117-25C (I know should be LT1004)
Power supply: 12 VDC switched mode + 7805 linear regulator.

Holy cow, all those wires...  :-+ In addition to what was said above, I would say that if you have any flux residue on the board, try to clean it off completely. That could help with the large resistance problem. Also, anchor down the wires that are anywhere near the probes. Their capacitance and inductance may be changing while measurement is in progress, thus making the tester think that it's looking at something other than what's really there. Lastly, a nice case might be able to isolate the probing conductors from the environment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alte on August 25, 2016, 09:10:00 am
Thanks, I could give that a try. I see a lot of firmware's in this thread ;), do you know which one I'd need for this specific tester ?

On page 93 post 2322 by stj has latest. Try the AY-AT
I had a bit of trouble to get avrdude to work, needed to hook up a crystal to be able to communicate with the 328. Once I could communicate I found the fuses for external crystal were indeed set, but flash was empty and there was some data in the eeprom.. Very strange, don't know what happened with that chip.
Then I could write the flash/eeprom/fuses and it verified ok. 
It did make a difference; only the backlight lit up and nothing else happened :'(  Then I found that there was only power to the chip and display while the button was pressed.
Turned out I swapped the 3k3 and 33k R7/R10 voltage divider resistors in the power circuit  :palm:
After fixing that (man it's difficult to desolder parts from a double sided PCB..) it's WORKING :-+
Thanks for your support guys !
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 25, 2016, 02:14:10 pm
Thanks, I could give that a try. I see a lot of firmware's in this thread ;), do you know which one I'd need for this specific tester ?

On page 93 post 2322 by stj has latest. Try the AY-AT
I had a bit of trouble to get avrdude to work, needed to hook up a crystal to be able to communicate with the 328. Once I could communicate I found the fuses for external crystal were indeed set, but flash was empty and there was some data in the eeprom.. Very strange, don't know what happened with that chip.
Then I could write the flash/eeprom/fuses and it verified ok. 
It did make a difference; only the backlight lit up and nothing else happened :'(  Then I found that there was only power to the chip and display while the button was pressed.
Turned out I swapped the 3k3 and 33k R7/R10 voltage divider resistors in the power circuit  :palm:
After fixing that (man it's difficult to desolder parts from a double sided PCB..) it's WORKING :-+
Thanks for your support guys !

I am glad you got it to work!  Yes I found the same thing about the double sided pcb, a real pain to desolder.  I ripped out a leg from LED trying to remove it.  When I put my AY-AT kit together, I put SRV05-04/MC5 front to back shorting VCC to GND :palm:

Yesterday, I was able to use avrdude with ArduinoISP wired directly to tester to flash SVN684 successfully.  I didn't use extra XTAL. 

Only thing I am missing is extra frequencies in f-gen.  Original firmware had 1mhz, 2mhz, and others...
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 25, 2016, 04:20:56 pm
Quote
Original firmware had 1mhz, 2mhz, and others...

if that's true then the original firmware must be seriously ancient.

the current official firmware has a variable oscillator, but it's very hard to use.
so my firmware has the older set-frequency code in it instead.
but i changed the available frequency's to usefull ones.

btw, i did put up a thread for several weeks asking people what frequency's would be usefull - not one reply!!
so i put the 50 & 60 Hz mains timebases and rectified derivatives in, together with a couple of tuning frequency's used by musicians.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 25, 2016, 05:07:52 pm
btw, i did put up a thread for several weeks asking people what frequency's would be usefull - not one reply!!

Was that a post in here or a separate thread?

Quote
so i put the 50 & 60 Hz mains timebases and rectified derivatives in, together with a couple of tuning frequency's used by musicians.

Those sound good.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 25, 2016, 05:40:07 pm
it was a seperate thread on a different forum.

the 50/60/100/120Hz is very usefull, because you can test stuff that normally gets timing pulses from a mains transformer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 25, 2016, 06:05:07 pm
it was a seperate thread on a different forum.

Ah, OK. That's why it didn't sound familiar.

Quote
the 50/60/100/120Hz is very usefull, because you can test stuff that normally gets timing pulses from a mains transformer.

Absolutely. There's also 400 Hz for some power systems (military?). Round numbers such as 1, 10, 100 kHz. I don't recall what the low end of the generator's range is, but there's 1 Hz for clock projects.

The U1252B I have uses the following presets for its frequency gen:

0.5, 1, 2, 5, 10, 15, 20, 25, 30, 40, 50, 60, 75, 80, 100, 120, 150, 200, 240, 300, 400, 480, 600, 800, 1200, 1600, 2400, 4800 Hz

It doesn't go very high, but it's interesting to see what they chose. I'm not sure why 1 kHz wasn't included.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 25, 2016, 06:33:02 pm
400Hz is 3phase, i'v never seen it used by any circuits though.

1Hz i wouldnt do.
the frequency's arent exact, they are divisions of the master clock.
and that's not exact either buy default.
although i'v seen testers with one or both of the 22pF crystal caps replaced by trimmers so the crystal could be tuned.
Title: INDEX
Post by: flywheelz on August 25, 2016, 06:40:45 pm
*Collection of Helpful information *
Firmware Building environment for Windows
Compiling the Firmware
Writing Firmware

Hardware
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 25, 2016, 07:01:59 pm
Quote
Original firmware had 1mhz, 2mhz, and others...

if that's true then the original firmware must be seriously ancient.

On start up it showed 1.12k

I think the list was 10Hz, 50Hz, 100Hz, 250Hz, 439.9956Hz, 441.9890Hz, 443.0170Hz, 1kHz, 2.5kHz, 5kHz, 10kHz, 25kHz, 50kHz, 100kHz, 153.8462kHz, 250kHz, 500kHz, 1mHz, 2mHz, 1000mHz
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 25, 2016, 07:38:51 pm

On start up it showed 1.12k


that does not mean anything, they have been labelled 1.12k for over a year.
that's why i use the SVN number.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 25, 2016, 07:41:55 pm
Hi, I am also trying to build myself.  I can't figure out what gcc related files I need grab from arduino zip and where to put them in Winavr folder to get it to work

I copied avr-gcc.exe, cc1.exe, device-specs folder, some dll... now its giving , make.exe: *** [lcd-routines.o] Error 1,  :wtf:

@stj, could you be more specific.
no i cant, but your not copying enough.
pm me your email - i'll archive my folder
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 25, 2016, 08:55:23 pm
[...] 1mHz, 2mHz, 1000mHz

I think that's 1MHz, 2MHz, but 1000mHz. Mega vs milli.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 25, 2016, 09:13:35 pm
Hi, I am also trying to build myself.  I can't figure out what gcc related files I need grab from arduino zip and where to put them in Winavr folder to get it to work

I copied avr-gcc.exe, cc1.exe, device-specs folder, some dll... now its giving , make.exe: *** [lcd-routines.o] Error 1,  :wtf:

@stj, could you be more specific.
no i cant, but your not copying enough.
pm me your email - i'll archive my folder

PM sent. But I think it might be working now...It compiles not exact file size as yours  but atleast it should fit... not sure about the dwarf errors.
Code: [Select]
BFD: Dwarf Error: mangled line number section.
BFD: Dwarf Error: mangled line number section.
BFD: Dwarf Error: mangled line number section.

8 MHz operation configured.
AVR Memory Usage
----------------
Device: atmega328p

Program:   31772 bytes (97.0% Full)
(.text + .data + .bootloader)

Data:        202 bytes (9.9% Full)
(.data + .bss + .noinit)

EEPROM:      888 bytes (86.7% Full)
(.eeprom)



> Process Exit Code: 0
> Time Taken: 00:58
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 25, 2016, 09:46:09 pm
my winavr is 20100110
i cant remember the arduino version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 25, 2016, 10:19:00 pm
my winavr is 20100110
i cant remember the arduino version.

I just compiler and flashed  svn690 with included Makefile in ../trunk/mega328_color_kit/  :-+  It boots up!  The f-Gen lets you select custom frequencies, wow  :clap:
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 26, 2016, 02:51:59 am
@madires,

I have mega328_color_kit "AY-AT" with LCD 7735.  Took trendy 1.24m for a drive.

To get LCD to work I had to change lines below.  One weird thing I see is on Start the LCD refreshes with multi color dots/sand.

In config_328.h:
1. From
Code: [Select]
#define LCD_ST7735_SPI
...
#define LCD_DC           PD3            /* port pin used for D/CX */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SDA          PD1            /* port pin used for SDA */
...
To
Code: [Select]
#define LCD_DC           PD1            /* port pin used for D/CX */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SDA          PD3            /* port pin used for SDA */

2. From
Code: [Select]
//#define LCD_FLIP_X                      /* enable horizontal flip */
#define LCD_FLIP_Y                      /* enable vertical flip */
To
Code: [Select]
#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y                      /* enable vertical flip */

And for Encoder changed:

3. From
Code: [Select]
#define ENCODER_A        PD2       /* rotary encoder A signal */To
Code: [Select]
#define ENCODER_A        PD1       /* rotary encoder A signal */


I also noticed in PWM and Square Wave modes it shows Pins 2-13.  I don't understand what it means  :-//

In variables.h
Code: [Select]
const unsigned char PWM_Probes_str[] EEMEM = "2-13"
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 26, 2016, 11:05:17 am
Thanks for the settings! I think, I'll add a dedicated file with the settings for the various tester versions/clones. So users just need to copy & paste. Back to your questions. The display isn't cleared directly at power up, because clearing the whole display is slow. That would interfere with the mode selection, which is based on how long you press the button when powering on. And it might irritate some users ("I've pressed the button, but nothing happens."). After the initial full clear only the lines used are cleared to speed up the process. "2-13" means that the signal is at probe/pin 2 and ground at probes/pins 1 and 3.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 27, 2016, 09:29:19 pm
The display isn't cleared directly at power up, because clearing the whole display is slow. That would interfere with the mode selection, which is based on how long you press the button when powering on. And it might irritate some users ("I've pressed the button, but nothing happens.").

The mode selection is done prior you do anything with the LCD so it should not interfere , I think.

Anyways, I've added command LCD_Clear() after line 1107: LCD_Init(); and this seem to solve the issue I saw with LCD 7735.  I don't notice any delay and screen stays black then text appear  :-+

changes in main.c
 
Code: [Select]

  1106: /* init LCD module */
  1107: LCD_Init();                           /* initialize LCD */
  1108: LCD_Clear();                          /* clear display */
  1109: LCD_NextLine_Mode(MODE_NONE);         /* reset line mode */
Title: Re: $20 LCR ESR Transistor checker project
Post by: ja421 on August 28, 2016, 12:23:16 am
On the color units (one just arrived, it wasn't supposed to be color); can the firmware be compiled as monochrome to regain some memory?  It is not put together, so I can't test it... Or can the display be swapped out for a mono display?  I don't think it's worth trying to send back (postage+time > what I paid for it), but don't want to bother putting it together if it's going to be crippled by lack of memory due to color display... tx
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 28, 2016, 12:25:55 am
the memory is tight, tens of bytes out.
so it may be o.k. with enough experimenting.

as it stands, the only option you cant fit in is the crystal test, and that needs a 16MHz crystal upgrade anyway.

btw, the monohrome stuff isnt much better - a case of "just fits" as opposed to "just over"
Title: Re: $20 LCR ESR Transistor checker project
Post by: ja421 on August 28, 2016, 12:33:34 am
aah; thanks.  I guess that's not as crippled as I thought it would be.
I can definitely live w/o a crystal test.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 28, 2016, 01:29:40 am
Maybe it my eyes but the AY-AT kit with color lcd 7735 that I got is not as crisp as monochrome displays (comparing screenshots).  Maybe its the fonts types or sizes not sure.  The screens physical dimensions are also smaller.  Finally, the slower refresh rate  :( but I got used to it.

The good thing is the color kits seem to be best bang for the buck.  You get the protection mod, encoder, dc jack and extra screw connectors already included.

When I compiled the latest k-firmware,  I get, "Program:   32550 bytes (99.3% Full)" and the m-firmware, "Program:   28158 bytes (85.9% Full)". 

@ja421,  Let us know who did a switch-a-roo on you.  Maybe you can file item not as discribed.  Regardless,  I hope the build go well.  These kits are super fun and freaking smart I tell ya.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 28, 2016, 01:50:44 am
Maybe it my eyes but the AY-AT kit with color lcd 7735 that I got is not as crisp as monochrome displays (comparing screenshots)
[/quote

maybe you left the protective film on the display :)
is there a small tab lower-right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 28, 2016, 02:39:53 am
Maybe it my eyes but the AY-AT kit with color lcd 7735 that I got is not as crisp as monochrome displays (comparing screenshots)
[/quote

maybe you left the protective film on the display :)
is there a small tab lower-right?

No, I took it off already.

What I need to do is get a unit with ST7565 screen and then compare it to ST7735.

btw, I've ordered 10 x SVR05-04 for $0.33 from Ali.  Will slap one back on my unit.  The original is still MIA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 28, 2016, 12:26:07 pm
The mode selection is done prior you do anything with the LCD so it should not interfere , I think.

LCD_BusSetup() is called before checking how long the push button is pressed.

Anyways, I've added command LCD_Clear() after line 1107: LCD_Init(); and this seem to solve the issue I saw with LCD 7735.  I don't notice any delay and screen stays black then text appear  :-+

changes in main.c
 
Code: [Select]

  1106: /* init LCD module */
  1107: LCD_Init();                           /* initialize LCD */
  1108: LCD_Clear();                          /* clear display */
  1109: LCD_NextLine_Mode(MODE_NONE);         /* reset line mode */

That's funny, because at the end of LCD_Init() LCD_Clear() is already called.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 28, 2016, 01:16:23 pm
On the color units (one just arrived, it wasn't supposed to be color); can the firmware be compiled as monochrome to regain some memory?  It is not put together, so I can't test it... Or can the display be swapped out for a mono display?  I don't think it's worth trying to send back (postage+time > what I paid for it), but don't want to bother putting it together if it's going to be crippled by lack of memory due to color display... tx

Color handling needs just a few bytes more in the firmware. And since color diplays mostly need 16bits per pixel instead of 1 bit any output is slowed down by that factor. What really impacts the firmware size is the font and the symbols. A smaller font/symbol size decreases the firmware.

The following is relevant for monochrome displays. A smaller font might create large gaps between lines on page-oriented displays. A page is an 8 bit high adressing area, i.e. you write a byte to address 8 pixels in a column. That could be solved by a display RAM buffer, but we don't got that luxury ;)

Most graphic displays are driven by SPI plus /CS, /RES and D/C. So chances are high that you can replace the color display with a monochrome one, if you prefer that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 28, 2016, 11:11:16 pm
The mode selection is done prior you do anything with the LCD so it should not interfere , I think.

LCD_BusSetup() is called before checking how long the push button is pressed.

Anyways, I've added command LCD_Clear() after line 1107: LCD_Init(); and this seem to solve the issue I saw with LCD 7735.  I don't notice any delay and screen stays black then text appear  :-+

changes in main.c
 
Code: [Select]

  1106: /* init LCD module */
  1107: LCD_Init();                           /* initialize LCD */
  1108: LCD_Clear();                          /* clear display */
  1109: LCD_NextLine_Mode(MODE_NONE);         /* reset line mode */

That's funny, because at the end of LCD_Init() LCD_Clear() is already called.

I have now removed the LCD_Clear() that I added expecting the display to show noise like before but it no longer is doing it.  I don't know what was going on before.  I will report back if it reappears.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 30, 2016, 01:38:52 am
@madires,

The weird issue is still there but only if I restart with the switch.  If restarting with SPI it doesn't show up.

https://youtu.be/EPsf8d41A60
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 30, 2016, 05:26:34 am
Is that with the extra LCD_Clear() or without it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 30, 2016, 06:10:50 am
Is that with the extra LCD_Clear() or without it?

The extra LCD_Clear() had no effect. I thought it did because I was doing SPI resets while testing the TT and was still connect to Arduino 5v rail effectively it never fully powered off.  I only see it when applying external power at DC jack.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 30, 2016, 06:18:42 am
maybe the display has a page-buffer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2016, 12:29:44 pm
@madires,
The weird issue is still there but only if I restart with the switch.  If restarting with SPI it doesn't show up.

The video was a great idea. :-+ It's not a bug, it' a feature. :) That "noise" is the uninitialized display RAM. Normally you would first clear the display/RAM and then turn the display output on. I'm doing it the other way around to give the user an immediate visual feedback when powering on. The video shows nicely how slow the initial LCD_Clear() is. For a ILI9341 (240 x 320) it takes about 2 or 3 seconds at 8MHz. Those LCD controllers don't got a fast built-in clear function and require you to send "black" (or whatever background color you prefer) for each pixel. Since the ST7735 isn't extremely slow, you could try and move the power-on section in LCD_Init() to the end. Maybe just LCD_Cmd(CMD_DISPLAY_ON), and removing MilliSleep(120).
Title: Index: $20 LCR ESR Transistor checker project
Post by: flywheelz on August 30, 2016, 03:51:00 pm


@madires,
The weird issue is still there but only if I restart with the switch.  If restarting with SPI it doesn't show up.

The video was a great idea. :-+ It's not a bug, it' a feature. :) That "noise" is the uninitialized display RAM. Normally you would first clear the display/RAM and then turn the display output on. I'm doing it the other way around to give the user an immediate visual feedback when powering on. The video shows nicely how slow the initial LCD_Clear() is. For a ILI9341 (240 x 320) it takes about 2 or 3 seconds at 8MHz. Those LCD controllers don't got a fast built-in clear function and require you to send "black" (or whatever background color you prefer) for each pixel. Since the ST7735 isn't extremely slow, you could try and move the power-on section in LCD_Init() to the end. Maybe just LCD_Cmd(CMD_DISPLAY_ON), and removing MilliSleep(120).

I followed your advice and we are noise free!   :-+

https://youtu.be/VzCNo60r0-E (https://youtu.be/VzCNo60r0-E)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 31, 2016, 12:33:00 am
TBH, for some reason it looks more attractive to me with the noise than without.  :-//

That SPI transfer looks painfully slow. Is this with an 8MHz crystal? Must be because it can't use the MCU's USART...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on August 31, 2016, 08:52:07 pm
Hmm... I wonder if instead of changing the colour for the whole field you can do a trick that we used back in the day on the BBC Micro in its monochrome MODE 0 or MODE 1 and was first used successfully on the original BBC Micro Elite ("Hi Res mono" for the game display, but "Lo Res colour" for the scanner/dashboard at the bottom of the screen). That alone was a marvel to me.

Basically it comes down to changing the mono colour pallette at a scan line interval. Of course there are no scan lines as such now, but you could easily separate say 3 obvious colour fields in the display and still get away with 1 bit rendering by applying the change at a couple of serial offsets?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 31, 2016, 09:25:28 pm
Nice idea, but I haven't seen any color LCD modules supporting a monochrome mode. Usually they have different color interface modes, like 12, 16 and 18 bits.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on August 31, 2016, 10:09:09 pm
@flywheelz and others,

[/quote]

I followed your advice and we are noise free!   :-+

[/quote]

Can you post that latest M version please?
Like to have a look at the M version, K version works OK BTW.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 01, 2016, 11:55:48 am
Please download 1.24m at https://github.com/svn2github/transistortester/tree/master/Software/Markus, and if you got the same clone (DIY Kit "AY-AT") as flywheelz, apply the changes he posted one page back.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 01, 2016, 03:52:54 pm
@flywheelz
Can you post that latest M version please?
Like to have a look at the M version, K version works OK BTW.

Thanks

Update:  I've removed the attachment because some testers got white screen.

Go HERE  (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1042941/#msg1042941)and get 1.25m with the fix compiled by jm_araujo.

Here is a compiled "Component Tester trendy v1.24m" firmware for mega328 color kit AY-AT with ST7735 lcd running @ 8MHz.  I have included the clean boot and what I called a magic lights versions.  Changed src files included. 

Features:


To get a Voltage reading, you have to press/hold switch.


Title: Re: $20 LCR ESR Transistor checker project
Post by: trex13 on September 01, 2016, 04:38:54 pm
Hi everybody,

Does anyone know why I can't download flash from working Chinese LCR-T4 tester using Arduino together with avrdude as ISP programmer ?

I have this version :

(https://ae01.alicdn.com/kf/HTB1JlmaKXXXXXbzXFXXq6xXFXXXg/2016-V2-68-ESR-T4-Mega328-Digital-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP.jpg_640x640.jpg)

I programmed my Arduino to act as ISP programmer, connected everything, run Avrdude from command prompt :

Code: [Select]
avrdude -c avrisp -p m328p -P COM3 -b 19200 -U flash:r:"MtesterFlash.bin":r -U eeprom:r:"MtesterEeprom.bin":r -U lfuse:r:"lfuse":r -U hfuse:r:"hfuse":r -U efuse:r:"efuse":r
At first it seemd OK, but later on I saw that flash file is empty while eeprom is OK but only 1KB in size :--:

Code: [Select]
C:\tester\noovi>avrdude -c avrisp -p m328p -P COM3 -b 19200 -U flash:r:"MtesterFlash.bin":r -U eeprom:r:"MtesterEeprom.bin":r -U lfuse:r:"lfuse":r -U hfuse:r:"hfuse":r -U efuse:r:"efuse":r

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: reading flash memory:

Reading | ################################################## | 100% 20.13s

avrdude: Flash is empty, resulting file has no contents.
avrdude: writing output file "Mtester207Flash.bin"
avrdude: reading eeprom memory:

Reading | ################################################## | 100% 3.33s

avrdude: writing output file "Mtester207Eeprom.bin"
avrdude: reading lfuse memory:

Reading | ################################################## | 100% 0.01s

avrdude: writing output file "lfuse"
avrdude: reading hfuse memory:

Reading | ################################################## | 100% 0.01s

avrdude: writing output file "hfuse"
avrdude: reading efuse memory:

Reading | ################################################## | 100% 0.01s

avrdude: writing output file "efuse"

avrdude: safemode: Fuses OK (E:FF, H:D7, L:FF)

avrdude done.  Thank you.

Having in mind that fuses are set like this : "E:FF, H:D7, L:FF" - Avrdude should be able to read flash

Does anyone have any idea?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 01, 2016, 05:02:12 pm
Reading the ATmega is disabled. But you can reset the fuses and program a new firmware. And the "original brand" is laughable. They've taken the orginal open source firmware and changed the display output. And the circuit is also open source.
Title: Re: $20 LCR ESR Transistor checker project
Post by: techie on September 01, 2016, 06:14:13 pm
Latest T3 / T4 schematics (Rev. 1d) courtesy of Roland Elmiger.

Note about flashing alternate software:
The latest pre-compiled version of Karl-Heinz software provided on "http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/" , v1.12k build 683, does not work (blank LCD screen) with the unmodified version of this tester.
This is due to a change in the Makefile made in March 2016:
line "#CFLAGS += -DPULLUP_DISABLE" was un-commented in build 661, making the LCD SPI interface open-drain with no pull-ups.
Hence, display data is not received by the LCD.

To restore proper operation on unmodified testers, make sure these options exist in the Makefile, and re-compile:
#CFLAGS += -DPULLUP_DISABLE
CFLAGS += -DLCD_SPI_OPEN_COL
CFLAGS += -DSTRIP_GRID_BOARD #(if it's a strip grid board - you made need to try both settings)

The LCD in these units requires +3V +/-10% VDD, while the Atmega runs on +5V VDD.  The PCB design includes two 1N4148 diodes in series from +5V VDD to the LCD VDD to attempt to drop the 5V down to something more reasonable for the LCD: ~3.6V, assuming 0.7V drop per diode. In reality, the LCD voltage is higher because of the small current drawn by the LCD, hence smaller diode drops.

Karl-Heinz suggests removing these two diodes and replacing them with a proper +3.3V LDO regulator, such as the MCP1703-3302.
He also recommends installing two additional pull-up resistors (10K - 30K) on the SCL and RST lines of the SPI bus between the Atmega and LCD.
They should pull-up to the +3.3V LCD supply.

If these hardware modifications are made, the compile Makefile options would be the same as the 683 build:
CFLAGS += -DPULLUP_DISABLE
CFLAGS += -DLCD_SPI_OPEN_COL
CFLAGS += -DSTRIP_GRID_BOARD #(if it's a strip grid board - you made need to try both settings)

Please see attached picture of suggested hardware mods from Karl-Heinz.

For owners of this tester which is offered on ebay under the designation as "LCR-T3" or "LCR-T4 Transistor Tester" I offer a way to update firmware. Devices have identical G-LCD (ST7565), but slightly different PCB. Update works on both versions of this tester. However, attention should be given to the fact that the ISP connector from the parts is mirrored. For this purpose I have pieced together a simple detachable :) adapter enabling the MCU to program without arranging the auxiliary ISP connector (see attached pictures). Many thanks to Roland Elmiger (hb9gaa) from the official discussion forum for providing the schematic diagram (http://www.mikrocontroller.net/topic/248078?page=6#3784106).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on September 01, 2016, 06:43:43 pm
Quote

Here is a compiled "Component Tester trendy v1.24m" firmware for mega328 color kit AY-AT with ST7735 lcd running @ 8MHz.  I have included the clean boot and what I called a magic lights versions.  Changed src files included. 

Features:
  • Enabled HW_Encoder
  • Enabled HW_REF25
  • Enabled HW_Zener
  • Enabled HW_FREQ_COUNTER
  • Disabled SW_IR_RECEIVER
  • Disabled SW_OPTO_COUPLER
  • Changed Menu label Zener to Voltage
To get a Voltage reading, you have to press/hold switch.

Thanks flywheelz,

Sorry to say but doesn't work for me, screen lights up, power stays on, but nothing on the display.
I have exact the tester as shown on your picture. Works OK with the K-version, svn 684
Maybe any tips, what can be wrong.

Thanks anyway for your effort.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 01, 2016, 07:57:33 pm
Have you compiled the firmware yourself or used the firmware provided by flywheelz? In the first case you need to change some pin and display settings (see flywheelz' post one page back).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on September 01, 2016, 08:47:08 pm
Have you compiled the firmware yourself or used the firmware provided by flywheelz? In the first case you need to change some pin and display settings (see flywheelz' post one page back).

I have used the firmware provided by flywheelz.
I don't have much knowledge about compiling and so on.
When I have time I hope to study that to.

Thanks for reply.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 01, 2016, 09:39:38 pm
there are several T4 variants around, some use "strip grid" and some dont.
and it pisses me off that they are all called T4
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 01, 2016, 09:48:55 pm
@Pukker
if you have SVN 684 then it probably came from me.
if so, it probably has the makefile in the zip - upload it for Flywheelz & others to use.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 01, 2016, 11:17:44 pm
hi !

im new and i need help :-)

http://www.ebay.at/itm/2016-EZM328-transistor-tester-ESR-frequency-meter-square-wave-genera-KITS-/172230778097?hash=item2819c11cf1:g:K8EAAOSwnNBXU~VH (http://www.ebay.at/itm/2016-EZM328-transistor-tester-ESR-frequency-meter-square-wave-genera-KITS-/172230778097?hash=item2819c11cf1:g:K8EAAOSwnNBXU~VH)

i am from austria and my english is not the best

i habe payd this but the chip is empty ;(

how can a download the hex ans eep file ?

thx Rudolf 
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 01, 2016, 11:18:45 pm
Thanks flywheelz,

Sorry to say but doesn't work for me, screen lights up, power stays on, but nothing on the display.
I have exact the tester as shown on your picture. Works OK with the K-version, svn 684
Maybe any tips, what can be wrong.

Thanks anyway for your effort.

I am surprised it did not work.  Maybe the kits are a little different.  If it powers on I am guessing the firmware is running but not talking to display correctly or on wrong data ports.  Try leave the tester powered on and if it turns off in about 30 seconds then firmware is running.

I will re test the previous files but in mean time you can try the attached firmware with default data ports 321.

Also check out this post, maybe it will get you compiling. *Collection of Helpful information * (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926)

edit:
I am new to fuses but the ones I used are : -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 01, 2016, 11:40:55 pm
hi !

im new and i need help :-)

http://www.ebay.at/itm/2016-EZM328-transistor-tester-ESR-frequency-meter-square-wave-genera-KITS-/172230778097?hash=item2819c11cf1:g:K8EAAOSwnNBXU~VH (http://www.ebay.at/itm/2016-EZM328-transistor-tester-ESR-frequency-meter-square-wave-genera-KITS-/172230778097?hash=item2819c11cf1:g:K8EAAOSwnNBXU~VH)

i am from austria and my english is not the best

i habe payd this but the chip is empty ;(

how can a download the hex ans eep file ?

thx Rudolf

code:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on September 02, 2016, 07:30:11 am
@Pukker
if you have SVN 684 then it probably came from me.
if so, it probably has the makefile in the zip - upload it for Flywheelz & others to use.

STJ

Yes that files came from you.
Works perfect.
Makefiles hereby. BTW, I didn't use them.

Thanks for willing to help.

Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 02, 2016, 05:40:35 pm
@Pukker,

I tried both the clean boot and the magic lights versions I posted on my unit and they work. 

Can you post pictures of your tester? 

Is it 8MHz or 16MHz? 

What fuses are you using?

@stj,
I also tried your svn684 v2 8MHz it worked fine.  I don't know really know why the 1.24m I compiled works on my AY-AT but not Pukker's.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 02, 2016, 05:50:26 pm
hi

Thanks for the software, problem view video

https://youtu.be/sUbec_VTAhI
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 02, 2016, 07:42:20 pm
i dont watch video's
(they hate my browser)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 02, 2016, 07:58:51 pm
i dont watch video's
(they hate my browser)
What the heck you still use Lynx from 1992?

From video, tester at menu, goes into "Transistor" by itself, shows a read of a 10.3ohm resistor then says "Timeout!" then turns off.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 02, 2016, 09:18:56 pm
hi

Thanks for the software, problem view video

https://youtu.be/sUbec_VTAhI

I have two of these testers im using the firmware you have downloaded and it works fine what are the fuse settings your using? what programmer are you using for the re programming,
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on September 02, 2016, 10:22:58 pm
@Pukker,

I tried both the clean boot and the magic lights versions I posted on my unit and they work. 

Can you post pictures of your tester? 

Is it 8MHz or 16MHz? 

What fuses are you using?

@stj,
I also tried your svn684 v2 8MHz it worked fine.  I don't know really know why the 1.24m I compiled works on my AY-AT but not Pukker's.

I've have exact the same unit as the picture in post 2506 from flywheelz
8Mhz crystal
Fuse used:
lfuse:w:0xF7
hfuse:w:0xD9
efuse:w:0x04

Thanks for reply.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 02, 2016, 10:23:55 pm
did you calibrate it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 02, 2016, 10:33:51 pm
hi

Thanks for the software, problem view video

https://youtu.be/sUbec_VTAhI (https://youtu.be/sUbec_VTAhI)

I have two of these testers im using the firmware you have downloaded and it works fine what are the fuse settings your using? what programmer are you using for the re programming,

(http://rudolf.heimat.eu/test/programmer.JPG)
(http://rudolf.heimat.eu/test/programmer1.JPG)

Flash and EEprom is ok, fuse not shure

Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 03, 2016, 12:41:32 am
@Rudolf_h,

Does the tester start automatically when you plug in battery?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 03, 2016, 12:44:04 am
did you calibrate it?

sry no ;.)

its work, but the hardwae must be bad

the led and the display is always on and the test buton and rotator not works 
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 03, 2016, 01:46:39 am
Have you checked the button to make sure there is no short in it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 03, 2016, 02:05:51 am
button is not shorted or he would start in the menu mode

it was a kit - probably a resistor is in the wrong place or something.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 03, 2016, 02:16:27 am
He does start in menu mode. And ends with "Timeout!"

Edit: I agree though, it could be something other than the button, but I think it's a good place to start.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 03, 2016, 03:27:21 am
Maybe Atmega pin 13 always grounded by switch on NPN transistor.

Disconnect battery then check pin 1 and 2 for short in pic attached.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 03, 2016, 12:44:00 pm
hi

Thanks for the software, problem view video

https://youtu.be/sUbec_VTAhI (https://youtu.be/sUbec_VTAhI)

I have two of these testers im using the firmware you have downloaded and it works fine what are the fuse settings your using? what programmer are you using for the re programming,

(http://rudolf.heimat.eu/test/programmer.JPG)
(http://rudolf.heimat.eu/test/programmer1.JPG)

Flash and EEprom is ok, fuse not shure

in your fuse settings lockbits i did not put anything in this section just the first three like you have set already and in extended fuse i set mine to 0x04
Thre is a good picture and zoomable so you can check the resistor colours etc in this thread post 349
 http://www.badcaps.net/forum/showthread.php?t=50720&highlight=esr+tester&page=18 (http://www.badcaps.net/forum/showthread.php?t=50720&highlight=esr+tester&page=18)
maybe worth double checking these are in the correct places too
u3 = tl431
q1 - 4673 (bc557c)
q2 - c945 (bc547)
q3 - c945 (bc547)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 03, 2016, 06:53:09 pm
@Rudolf_h,

Does the tester start automatically when you plug in battery?

yes its start auto and is in a loop

transistor have i new and the start button has no bridge .. sorry bad english

https://www.youtube.com/watch?v=2H5j5LHh0Jc&feature=youtu.be (https://www.youtube.com/watch?v=2H5j5LHh0Jc&feature=youtu.be)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 03, 2016, 07:10:19 pm
@Rudolf_h,

Does the tester start automatically when you plug in battery?

yes its start auto and is in a loop

transistor have i new and the start button has no bridge .. sorry bad english

https://www.youtube.com/watch?v=2H5j5LHh0Jc&feature=youtu.be (https://www.youtube.com/watch?v=2H5j5LHh0Jc&feature=youtu.be)

your video is set to private so we cant view it
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 03, 2016, 07:47:25 pm
@Rudolf_h,

Does the tester start automatically when you plug in battery?

yes its start auto and is in a loop

transistor have i new and the start button has no bridge .. sorry bad english

https://youtu.be/2H5j5LHh0Jc (https://youtu.be/2H5j5LHh0Jc)

the extendet is 0x04 ... xxxxx100 ignore the 5 bits

https://www.youtube.com/watch?v=2H5j5LHh0Jc&feature=youtu.be (https://www.youtube.com/watch?v=2H5j5LHh0Jc&feature=youtu.be)

your video is set to private so we cant view it
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 03, 2016, 07:52:29 pm
i have checkt resistor many times .. all ok and on the right place

no brocken or bridges copper 

now i have test pin 27 ( PC4 ) is always 2,5V on the pin
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 03, 2016, 08:02:27 pm
PC4 is the external 2.5V voltage reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 03, 2016, 09:11:32 pm
PC4 is the external 2.5V voltage reference.

sry my misstake wrong pin

when i press the test button must go pin 13 ( u1-13 ) to gnd ? is 0,6V presst or no presst test button

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 03, 2016, 09:30:32 pm
PD7 (pin 13) is pulled up by a 27k resistor, when the push button isn't pressed. When you press the push button, a transistor pulls down PD7 to gound.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 03, 2016, 09:35:28 pm
PD7 (pin 13) is pulled up by a 27k resistor, when the push button isn't pressed. When you press the push button, a transistor pulls down PD7 to gound.
can you upload a high resolution picture of your tester like in the link in the thread i posted earlier we maybe able to spot something your missing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 03, 2016, 09:49:55 pm
He is getting 0.6v at pin 13 at all times which is wrong.  As madires said it should be about 5v when the push button isn't pressed.  Perhaps that Q3 is wrong transistor S9014 but for that tester you need c945 with different pinout? 

What part number of Q3?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 03, 2016, 10:08:16 pm
He is getting 0.6v at pin 13 at all times which is wrong.  As madires said it should be about 5v when the push button isn't pressed.  Perhaps that Q3 is wrong transistor S9014 but for that tester you need c945 with different pinout? 

What part number of Q3?

first c945 and now bc547B


ok... i see ;-) 

original c945 
           BC547

in the GM328R stuffing list  q2& q3 - c945 ( bc547) !!

(http://rudolf.heimat.eu/test/pin.JPG)

not pin compatible
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 03, 2016, 10:17:34 pm
PD7 (pin 13) is pulled up by a 27k resistor, when the push button isn't pressed. When you press the push button, a transistor pulls down PD7 to gound.

thats the problem, the is 0,6v presst or no presst 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 03, 2016, 10:28:09 pm
PD7 (pin 13) is pulled up by a 27k resistor, when the push button isn't pressed. When you press the push button, a transistor pulls down PD7 to gound.
can you upload a high resolution picture of your tester like in the link in the thread i posted earlier we maybe able to spot something your missing.
(http://rudolf.heimat.eu/test/neu3.JPG)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rudolf_h on September 03, 2016, 11:19:26 pm
He is getting 0.6v at pin 13 at all times which is wrong.  As madires said it should be about 5v when the push button isn't pressed.  Perhaps that Q3 is wrong transistor S9014 but for that tester you need c945 with different pinout? 

What part number of Q3?

Thanks to all ;.)  |O |O

its works now Perfekt ;-) 

Transitor wrong i insert original and now  :D :D :D :D :D :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 04, 2016, 01:19:21 am
Good job Rudolf!  One more working tester for the team.  :-+  :popcorn:
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 04, 2016, 06:12:06 am
I want to upgrade my AtMega328p-PU (the DIP part) to the latest repository 'madires' FW, but the part is locked.

- Can the ISP be used to completely erase a locked device ? Or, that a parallel HV programmer must be used ?
- I have the TL866 parallel programmer. How do I load it with both the *.hex & *eep files ?

TIA
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 04, 2016, 06:24:21 am
I want to upgrade my AtMega328p-PU (the DIP part) to the latest repository 'madires' FW, but the part is locked.

- Can the ISP be used to completely erase a locked device ? Or, that a parallel HV programmer must be used ?
- I have the TL866 parallel programmer. How do I load it with both the *.hex & *eep files ?

TIA

Yes you can Erase and start fresh. 

I don't have any experience with TL866 but others here do.  Here is such a post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1009942/#msg1009942).  Also I remember something about opening files as "intel".
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 04, 2016, 06:57:40 am
Yes you can Erase and start fresh. 
Erase - Using ISP ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 04, 2016, 07:12:47 am
Yes you can Erase and start fresh. 
Erase - Using ISP ?

Yes. Should be no problem erasing unless they disabled ISP then you need HV programmer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 04, 2016, 07:33:04 am
I am always confused.

- Does "SPIEN=0" checked, mean ENABLE SPI serial programming ?
- Also as I recall, goofing around with the LOCK bits may (among other things) disable SPI programming.

OK anyways, I'll try. Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 04, 2016, 09:16:07 am
good and bad news

good news, lock bits cant effect spi.

bad news, some programmer software uses "0" instead of "1" and "1" instead of "0"
(and should be shot for it - several times in the head)

that's why it's best to use fusebyte values in hex rather than individual fuse states.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on September 04, 2016, 11:20:38 am

- Does "SPIEN=0" checked, mean ENABLE SPI serial programming ?


SPIEN=0 does mean enabled.

Although I guess anything is possible, I doubt that any programmers actually ask you to put in a '0' to mean a '1' (unprogrammed). In AVR chips, '0' is always programmed and '1' is always unprogrammed. This is a function of how the memory is made. The natural (unprogrammed) state is '1' hence the all FF's when looking at a blank chip.

I think stj is referring to the fact that some programmers try to make it easier to understand by using a check mark to mark a bit as programmed (i.e. value of bit = 0).
Where this can get confusing is when the chip manufacturer sometimes uses '0' (programmed) to mean enable that function (e.g. SPIEN=0 is SPI enabled) and at other times uses '0' to disable a function (e.g. RSTDISBL=0 is External Reset is Disabled). Note, that the actual function name from the datasheet often includes the function state ('EN', "DISBL', 'ON' etc) and when this is referenced, the choice of programmed or unprogrammed becomes clear.

The key to avoiding misunderstandings is to ALWAYS refer to the chip datasheet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 04, 2016, 12:18:55 pm
probably a good time to post this link.
http://www.engbedded.com/fusecalc (http://www.engbedded.com/fusecalc)
 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: kodi on September 04, 2016, 03:02:20 pm
Just quick question -I built the Banggood kit - namely this one  http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html). So at the first run I calibrated it and it all went ok, got few sample elements and everything was fine. However - today I was making an enclosure for this. And when I tested it it shows that there is 200-350pF capacitance between 1 and 3. I took it out of the enclosure and I am still getting same results. Is it possible I killed the the MCU by touching it or something?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 04, 2016, 03:28:25 pm
did you clean all the flux off?
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 04, 2016, 03:40:27 pm
probably a good time to post this link.
http://www.engbedded.com/fusecalc (http://www.engbedded.com/fusecalc)
 :)
Nice one !
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 04, 2016, 03:45:01 pm
Although I guess anything is possible, I doubt that any programmers actually ask you to put in a '0' to mean a '1' (unprogrammed). In AVR chips, '0' is always programmed and '1' is always unprogrammed. This is a function of how the memory is made. The natural (unprogrammed) state is '1' hence the all FF's when looking at a blank chip.
Look here (a snapshot at TL866 Programmer SW) - and see how it is confusing (0xFF == 0x00...)
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on September 04, 2016, 04:43:26 pm
Although I guess anything is possible, I doubt that any programmers actually ask you to put in a '0' to mean a '1' (unprogrammed). In AVR chips, '0' is always programmed and '1' is always unprogrammed. This is a function of how the memory is made. The natural (unprogrammed) state is '1' hence the all FF's when looking at a blank chip.
Look here (a snapshot at TL866 Programmer SW) - and see how it is confusing (0xFF == 0x00...)

NO!!!!!!! It is NOT saying 0xFF == 0x00

You left out of the quote from my post the following: "some programmers try to make it easier to understand by using a check mark to mark a bit as programmed (i.e. value of bit = 0). "
I was actually thinking of the TL866 when I wrote that.

Lets look specifically at the Lock Bit entries.

All the check boxes are currently UNCHECKED.
Next to the check box, the label says that the value WILL BE set to '0' (i.e. programmed) IF you check this box
In your image, all lock bit entries are UNCHECKED, meaning that the value of each bit is '1' (i.e. NOT Programmed
Therefore, down below in the config information, the value of all 8 bits of the lock byte are = 1 so the byte is equal to 0xFF.

Remember on the AVR chips a value of '0' in a bit is ALWAYS = 'Programmed' Only by knowing the function of that bit, can you tell whether or not it is enabled.
For example:
To ENABLE the lock bits (you DO NOT want to do this), you would check all those boxes which would set the Lock Fuse Byte to 0x00.
To ENABLE the SPI, you would check the SPIEN box which will set it to '0'
To DISABLE the external reset (you also DO NOT want to do this), you would check the RSTDISBL box which will set it to '0'

Hope this helps. The TL866 is absolutely correct. Our confusion comes from the fact that we tend to think of '1' as 'On and '-' as OFF. Because of the way flash memory is made in the AVR, they start off by making us remember that '1' is NOT Programmed and '0' is programmed. If that hasn't confused us enough, they then define some functions to be on when the chip is unprogrammed and others to be off. This is why it is important to pay attention to the complete function name which gives us a hint whether activating it will enable something or disable it.

[edit]
Note in the ATMega328 there are actually only 6 lock bits. Bit 6 and 7 of that byte are not used. There are also unused bits in the Extended Fuse Byte.
Some programmers may read an absent bit as a '0' but in an AVR it should actually be read as a '1'. This can cause verification errors which can be ignored. Again, you need to be familiar with the Datasheet.


Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 04, 2016, 05:46:33 pm
I didn't say that some programmers NOT try to make it easier to understand.
I said it is CONFUSING. At least me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kodi on September 04, 2016, 06:01:44 pm
did you clean all the flux off?
Yes - that's was my first thought. Board was cleaned before the first run with isopropyl alcohol.
Ok - just to be sure - I just blew some compressed air on it and it works again  :-//
Thanks for the help!
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 05, 2016, 07:36:29 am
I didn't say that some programmers NOT try to make it easier to understand.
I said it is CONFUSING. At least me.

It was confusing to me at first, too. Seemed totally backwards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: NiklasO on September 06, 2016, 08:56:51 pm
Attaching some pictures from inside of my newly delivered TC-1 (LCR-T6?) with full color screen.

Seems to be working great. The battery was really small so I changed it for a 1750 mAh one. Adds som weight. (I like it).

Other pics I found earlier:
https://yadi.sk/d/yW8xa5NJgUo5z/%D0%A2%D0%A1-1/Photo
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 07, 2016, 11:26:33 am
I've got this exact kit :
http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

and built it with the instructions i've found here.
But all I get is a blank screen.(no backlight)

When I press the encoder I just get the LCD to light up.
What could be wrong?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 07, 2016, 12:22:37 pm
I've got this exact kit :
http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

and built it with the instructions i've found here.
But all I get is a blank screen.(no backlight)

When I press the encoder I just get the LCD to light up.
What could be wrong?

A few of us have built these kits when there shipped some have no data on the atmrga ic so you have to reload the correct hex eep files
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 07, 2016, 01:24:04 pm
Doh!
So there is nothing wrong with the hardware?

Thing is I don't have an eeprom programmer at hand..
Do I have to get one of these TL866s  to do that?!


edit:I have an arduino uno board if that helps..
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 07, 2016, 01:41:30 pm
Doh!
So there is nothing wrong with the hardware?

Thing is I don't have an eeprom programmer at hand..
Do I have to get one of these TL866s  to do that?!


edit:I have an arduino uno board if that helps..

a few people have used arduino and avrdude etc ive not used arduino myself so cant help with programming it
or you could use one of these http://www.ebay.co.uk/itm/like/172308179849?lpid=122&chn=ps&googleloc=9045944&poi=&campaignid=620800750&device=c&adgroupid=27378723426&rlsatarget=pla-181480839426&adtype=pla&crdt=0 (http://www.ebay.co.uk/itm/like/172308179849?lpid=122&chn=ps&googleloc=9045944&poi=&campaignid=620800750&device=c&adgroupid=27378723426&rlsatarget=pla-181480839426&adtype=pla&crdt=0)
and solder some wires from the header too the ic and programe it that way
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 07, 2016, 01:57:33 pm
Thanks for your help but I'm not at all familiar with these things!

I've never used an eeprom programmer and I don't have have one here either so I'm probably going to gave to take it to the seller to send me a preprogrammed atmega (or refund me because I received something that does not work)


I'll buy this little gizmo in the meantime but without a step by step guide I think I'll only make things worse..
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 07, 2016, 02:28:08 pm
I would not get TL866 just for flashing the tester unless you plan to flash many other chips. Plus it's cost quite a bit.

Just like you I have Arduino Uno and have been using it to flash the tester without any issues. You only need to connect 6 wires and load ArduinoISP sketch on Arduino. I have solder pin headers right to the underside to the appropriate pins of Atmega. I have not tried to flash the Atmega on the breadboard which might need an external crystal and few caps, not sure. If you decide to go this route I can help you along.

Recently I ordered a $2 USBasp programmer that will replace the Arduino Uno.

Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 07, 2016, 03:01:44 pm
Thanks flywheels;  I'd be very glad if you assist me thru this process!

I only have the UNO though.(and 6 wires:p)

If I don't need to purchase anything else we can do this whenever you can.

I found this page that should get me started on the arduino side of things.
https://www.arduino.cc/en/Tutorial/ArduinoISP (https://www.arduino.cc/en/Tutorial/ArduinoISP)




Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 07, 2016, 04:02:03 pm
Thanks flywheels;  I'd be very glad if you assist me thru this process!

I only have the UNO though.(and 6 wires:p)

If I don't need to purchase anything else we can do this whenever you can.

I found this page that should get me started on the arduino side of things.
https://www.arduino.cc/en/Tutorial/ArduinoISP (https://www.arduino.cc/en/Tutorial/ArduinoISP)

http://www.instructables.com/id/Burning-the-Bootloader-on-ATMega328-using-Arduino-/ (http://www.instructables.com/id/Burning-the-Bootloader-on-ATMega328-using-Arduino-/)
post 552 in this thread may help too as we was helping another member use arduino
http://www.badcaps.net/forum/showthread.php?t=50720&highlight=esr+tester&page=28 (http://www.badcaps.net/forum/showthread.php?t=50720&highlight=esr+tester&page=28)
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 07, 2016, 04:37:07 pm
Thanks a ton vinceroger.!
I'll post back when I've got something.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 07, 2016, 04:51:23 pm
Thanks flywheels;  I'd be very glad if you assist me thru this process!

I only have the UNO though.(and 6 wires:p)

If I don't need to purchase anything else we can do this whenever you can.

I found this page that should get me started on the arduino side of things.
https://www.arduino.cc/en/Tutorial/ArduinoISP (https://www.arduino.cc/en/Tutorial/ArduinoISP)

Here is how to Wire it up, see attachments. 

Then, Start Arduino IDE and upload example ArduinoISP.  Disconnect Arduino from USB.  Connect Tester to Arduino then plug in the USB.

Next I installed latest WinAvr.  It will install avrdude for you or just get it alone.  Then I go to command prompt and type:
Code: [Select]
avrdude -c avrisp -p m328p -P COM3 -b 19200 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0x04:m
or for your tester might be
Code: [Select]
avrdude -c avrisp -p m328p -P COM3 -b 19200 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0xfc:m
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on September 07, 2016, 07:09:32 pm
I've got this exact kit :
http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

and built it with the instructions i've found here.
But all I get is a blank screen.(no backlight)

When I press the encoder I just get the LCD to light up.
What could be wrong?
I'm probably going to gave to take it to the seller to send me a preprogrammed atmega (or refund me because I received something that does not work)
That seller is a muppet, I bought mine from him, as did vinceroger on this site.
They all came unprogrammed and without component schematic.
First the seller sent me a link to the "correct" firmware: which was the wrong bloody firmware (a model with a completely different LCD so no display with it).
The seller even sent me a new Atmega, and guess what: Neither it was not programmed!
The good news is after programming with the firmware that stj posted a while back it works great!

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg997651/#msg997651 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg997651/#msg997651)
"GM328x ESR tester (SVN684) - v2"

in your fuse settings lockbits i did not put anything in this section just the first three like you have set already and in extended fuse i set mine to 0x04
Thre is a good picture and zoomable so you can check the resistor colours etc in this thread post 349
 http://www.badcaps.net/forum/showthread.php?t=50720&highlight=esr+tester&page=18 (http://www.badcaps.net/forum/showthread.php?t=50720&highlight=esr+tester&page=18)
I posted the same pictures here as well:)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg983525/#msg983525 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg983525/#msg983525)
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 07, 2016, 08:34:41 pm

That seller is a muppet, I bought mine from him, as did vinceroger on this site.
They all came unprogrammed and without component schematic.
First the seller sent me a link to the "correct" firmware: which was the wrong bloody firmware (a model with a completely different LCD so no display with it).
The seller even sent me a new Atmega, and guess what: Neither it was not programmed!
The good news is after programming with the firmware that stj posted a while back it works great!


I'm going to try the instructions as soon as the 22pF caps I ordered arrive!
I didn't have any in stock so I guess I'm going to have to wait.
I've just ordered them so it's going to take some time.

I've already sent a message to the seller about the issue ;I also asked for a refund or a ready built unit(without accessories etc)

I don't feel well asking for a refund and I avoid it if I can but since I haven't got what the listing stated (a working transistor tester) I think I am eligible for it.
My job was only to solder a bunch of components,not trying to guess what's wrong with or programming the friggin atmega!

I thought that proposing him to send me just the atmega was risky and here you are actually confirming my thoughts!

Funny thing is that yesterday I bought a dds function generator KIT from the same seller!
His/Hers feedback is very good; I didn't know better..
I'll let you guys know what happens.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 07, 2016, 08:47:52 pm
did you see post Reply #2574 on page 103 if you do it that way i dont think you need the extra capacitors?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 08, 2016, 01:12:14 am
you dont need any caps or crystal, they are already on the component tester pcb - just connect wires to the socket pins under the board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 04:49:49 pm
Okay,I wired the arduino directly to the tester socket underneath (6-wire pinout as shown in the instructables link).
I have arduino ide version 1.6.11 installed.
What should I do now?
I also copied my arduino folder from Program Files to Desktop in case I need to follow the instructables guide up to that point.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 05:22:36 pm
Thanks flywheels;  I'd be very glad if you assist me thru this process!

I only have the UNO though.(and 6 wires:p)

If I don't need to purchase anything else we can do this whenever you can.

I found this page that should get me started on the arduino side of things.
https://www.arduino.cc/en/Tutorial/ArduinoISP (https://www.arduino.cc/en/Tutorial/ArduinoISP)

Here is how to Wire it up, see attachments. 

Then, Start Arduino IDE and upload example ArduinoISP.  Disconnect Arduino from USB.  Connect Tester to Arduino then plug in the USB.

Next I installed latest WinAvr.  It will install avrdude for you or just get it alone.  Then I go to command prompt and type:
Code: [Select]
avrdude -c avrisp -p m328p -P COM3 -b 19200 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0x04:m
or for your tester might be
Code: [Select]
avrdude -c avrisp -p m328p -P COM3 -b 19200 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0xfc:m


Wow!
I just saw this post ::)
Trying it now..
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 08, 2016, 05:35:05 pm
what o.s. are you using btw?
because win10 is junk and needs special treatment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 08, 2016, 05:35:55 pm
the firmware files you have downloaded for your tester remember too un zip them what i had to do is once i unzipped the folder was move the files into the avr folder but not sure if you need to do this as your using arduino maybe another member will confirm where you need too place the firmware files
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 05:41:05 pm
what o.s. are you using btw?
because win10 is junk and needs special treatment.

Win7 (not that crap of os win 10).

I have so far :

a)Uploaded the arduino isp sketch (forgot to unwire the tester while doing so ;so I did it again without the 5v going to tester attached).
b)Downloaded the winavr and installed it.
I have the EZM tester from this listing : http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 08, 2016, 05:46:06 pm
The firmware you need for the tester is in post 2566
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 08, 2016, 05:47:47 pm
you dont need winavr
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 05:51:49 pm
I have the firmware; just don't know where to place the .eep and .hex files and how to send them to the tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 05:59:02 pm
I have the arduino connected and the files placed in my c:\ folder.
I opened a CMD window and copied this command
avrdude -c USBasp -P usb -p m328p -U flash:w:TransistorTester.hex \-U eeprom:w:TransistorTester.eep \-U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m

but it says it can't find the usbasp device..
Maybe I should call it usbisp?!(I really have no clue what I'm doing now..)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 08, 2016, 06:04:05 pm
Send the command in my previous post.  If you are using Arduino, you must use avrisp not usbasp. Also make sure that com port matches and baud 19200 unless you edited it the sketch.

The .hex and .eep files need to be in same directory where you open the command prompt.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 06:10:24 pm
The command stops reporting :

stk500_getsync():not in sync :resp 0x00 < 00 not 60
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 08, 2016, 06:14:23 pm
The command stops reporting :

stk500_getsync():not in sync :resp 0x66

If the command is correct then if could be wiring problem.

Does the testers back light come on when you plug in USB in Arduino?
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 06:16:12 pm
Yes the backlight turns on!
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 06:18:07 pm
The firmware files are on C:\
Should I place them elsewhere maybe?
My port is COM4 btw.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 08, 2016, 06:25:16 pm
The firmware files are on C:\
Should I place them elsewhere maybe?
My port is COM4 btw.

Make sure the tester is connected to Arduino, then plug in usb.

Start cmd.exe, type cd\, press ENTER.

Paste:
Code: [Select]
avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0x04:m
press ENTER.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 08, 2016, 06:27:19 pm
http://www.parkansky.com/arduino-error.htm (http://www.parkansky.com/arduino-error.htm)
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 06:46:27 pm
The firmware files are on C:\
Should I place them elsewhere maybe?
My port is COM4 btw.

Make sure the tester is connected to Arduino, then plug in usb.

Start cmd.exe, type cd\, press ENTER.

Paste:
Code: [Select]
avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0x04:m
press ENTER.

Still same error!
Problem is I don't have any wires going to pin 0!
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 08, 2016, 06:48:50 pm
The command stops reporting :

stk500_getsync():not in sync :resp 0x00 < 00 not 60

Something wrong with your Arduino.  I just disconnected the tester and issued:  avrdude -c avrisp -p m328p -P COM3 -b 19200

I get this,

Code: [Select]
C:\>avrdude -c avrisp -p m328p -P COM3 -b 19200

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.05s

avrdude: Device signature = 0x000000
avrdude: Yikes!  Invalid device signature.
         Double check connections and try again, or use -F to override
         this check.


avrdude done.  Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 06:50:07 pm
Maybe I need to erase the tester's chip first in case I accidentaly wrote something into it when I uploaded the sketch to the arduino?Or this procedure overwrites everything?
Maybe change something from arduino IDE like arduino as isp or something?
I checked for continuity and all the wires seem solid.
There's not much left except maybe a somehow damaged atmega..
My arduino is a clone btw..
Maybe just try re-uploading the sketch?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 08, 2016, 06:53:50 pm
The firmware files are on C:\
Should I place them elsewhere maybe?
My port is COM4 btw.

Make sure the tester is connected to Arduino, then plug in usb.

Start cmd.exe, type cd\, press ENTER.

Paste:
Code: [Select]
avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":i -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0x04:m
press ENTER.

Still same error!
Problem is I don't have any wires going to pin 0!

sorry yes just read the guides and look at pictures posted nothing connects too pin 0 have you used your clone tester before? maybe order a usbasp  from ebay there really cheap and do work but not sure how long shipping takes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 07:08:17 pm
I've used the clone only for a couple of simple sketches just to test it's working.nothing fancy..
I can upload sketches to it no problem so it shouldn't be defective..who knows though.

I'm going to order one of these usbasps,in fact I've just ordered one.Shipping's going to take a while.

I'm really curious what could be wrong here.The isp sketch I uploaded is this :
https://github.com/rsbohn/ArduinoISP/blob/master/ArduinoISP/ArduinoISP.ino

Just copied the text;verified and uploaded it to arduino.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 08, 2016, 07:34:44 pm
This video helped me regarding setting up avrdude etc and the programming side of things
https://www.youtube.com/watch?v=J_LYhHUS26c&index=81&list=WL (https://www.youtube.com/watch?v=J_LYhHUS26c&index=81&list=WL)
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 07:51:07 pm
Thanks!
I guess I'll wait for the usbasp to arrive (15-20 days)

I don't what's wrong with my arduino.

I tried flywheels avrdude -c avrisp -p m328p -P COM4 -b 19200 and I got the same error with no wires attached so it must be the arduino.

I don't know why it doesn't communicate properly with the avrdude command.
Thing is that I'm able to to upload sketches via the Arduino IDE .
If it was something wrong with the drivers or so ,wouldn't it be unable to work with the IDE as well?

If there was a way to send the files within the IDE maybe it could work but I don't know the way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 08, 2016, 08:00:25 pm
someone may have some idea whats wrong dont give up just yet double check your wires are on the correct pins on the atmega 328p etc as we have all made mistakes in the past. for my usbasp programmer ive also brought the socket and hard wired it to my ic pins so any time i want to update the firmware i can easily although i do have the tl 866 programmer too avrdude seems quicker.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 08:11:28 pm
Do u have a link for the socket?
Is this it?
http://www.ebay.com/itm/AVR-ATMEGA16-Minimum-System-Board-ATmega32-USB-ISP-USBasp-Programmer-For-ATMEL-/201622104604?hash=item2ef19d2a1c:g:w8sAAOSwzLlXhUNE (http://www.ebay.com/itm/AVR-ATMEGA16-Minimum-System-Board-ATmega32-USB-ISP-USBasp-Programmer-For-ATMEL-/201622104604?hash=item2ef19d2a1c:g:w8sAAOSwzLlXhUNE)

I might get a tl866 myself although whenever I need a 27cXXX or something a friend of mine just burns me one but tl866s are nice for the price and handy if you need an eprom in a hurry..
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 08, 2016, 08:21:01 pm
no thats the wrong one in that ebay link its just a small 10 pin socket the part you have already ordered plugs into it.i will see if i can find a link
http://uk.rs-online.com/web/p/idc-connectors/6257252/ (http://uk.rs-online.com/web/p/idc-connectors/6257252/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 08, 2016, 08:32:07 pm
Do u have a link for the socket?
Is this it?
http://www.ebay.com/itm/AVR-ATMEGA16-Minimum-System-Board-ATmega32-USB-ISP-USBasp-Programmer-For-ATMEL-/201622104604?hash=item2ef19d2a1c:g:w8sAAOSwzLlXhUNE (http://www.ebay.com/itm/AVR-ATMEGA16-Minimum-System-Board-ATmega32-USB-ISP-USBasp-Programmer-For-ATMEL-/201622104604?hash=item2ef19d2a1c:g:w8sAAOSwzLlXhUNE)

I might get a tl866 myself although whenever I need a 27cXXX or something a friend of mine just burns me one but tl866s are nice for the price and handy if you need an eprom in a hurry..

can you take you atmega ic out and put the files on a disk/usb stick then maybe a local computer shop in your area will burn the files to the ic cheap/free for you saves waiting too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 08, 2016, 10:52:33 pm
I managed to write the firmware. :)
My arduino was ok too, but I was an idiot and the isp sketch I kept uploading wasn't the correct one..

I tried Files>Examples>Arduino ISP and uploaded that and it worked!
It was in front of me the whole time.

Anyways,thanks for all the help!(especially flywheelz for the guide/commands)

Now I think I have to calibrate it..
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 09, 2016, 04:25:19 am
Good job!  Another one for the team  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 09, 2016, 08:09:41 am
Is there a YouTube video or a manual/guide on how to calibrate this thing?
I've found some videos on YT but they're for different firmware versions..
I shorted pins 1-2-3 and entered selftest mode but I get some random values along the way.
I then put a 320nF polyester cap (no 220nF as advised but said >200 so it should be ok) and then I'm not really sure what I was doing.
In the end the test completed and now I seem to have a functional unit but I think I may have to recalibrate it properly.

I followed the instructions here (seems to be pretty close to my version).
https://www.youtube.com/watch?v=mJKSffZfyJw (https://www.youtube.com/watch?v=mJKSffZfyJw)

Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 09, 2016, 08:30:48 am
There are also instruction on the calibration process on the ttester.pdf manual!
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 09, 2016, 10:32:51 am
you did it correctly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 09, 2016, 10:35:39 am
I managed to write the firmware. :)
My arduino was ok too, but I was an idiot and the isp sketch I kept uploading wasn't the correct one..

I tried Files>Examples>Arduino ISP and uploaded that and it worked!
It was in front of me the whole time.

Anyways,thanks for all the help!(especially flywheelz for the guide/commands)

Now I think I have to calibrate it..

Im glad you have managed too get your tester working they are good meters in my opinion,
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 09, 2016, 03:28:26 pm
Yeah, these simple and cheap testers are awesome! Sometimes I'm amazed how much we can achieve with the firmware. And it's still fun to add new features and improve measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 09, 2016, 05:43:07 pm
I agree with madires, amazing gadget!  The other thing that stands out from this project is a type of people that are involved in it.  Everyone from developers, fw cookers, helpers, etc, I would be honored to shake your hand for the job well done.


While testing, I found 1.12k svn690 seem to detect this JFET ok but 1.24m trendy having a bad day at the office.

datasheet
https://www.fairchildsemi.com/datasheets/MP/MPF102.pdf (https://www.fairchildsemi.com/datasheets/MP/MPF102.pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 09, 2016, 07:36:09 pm
If you're talking about the pinout, k and m-firmware differ. J-FETs are often symmetrical. The k-firmware will display the assumed Source and Drain pins, but they could be also vice versa. IIRC, Karl-Heinz explains that in the documentation. The m-firmware checks if the J-FET seems to be symmetrical and displays "x" for the Source and Drain pins to indicate that. A measurement of the Gate-Source and Gate-Drain capacitance would identify Source and Drain or a symmetrical J-FET reliably, but the Tester's circuit doesn't support that. It would require a DC bias and an AC based capacitance measurement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 09, 2016, 08:48:53 pm
If you're talking about the pinout, k and m-firmware differ. J-FETs are often symmetrical. The k-firmware will display the assumed Source and Drain pins, but they could be also vice versa. IIRC, Karl-Heinz explains that in the documentation. The m-firmware checks if the J-FET seems to be symmetrical and displays "x" for the Source and Drain pins to indicate that. A measurement of the Gate-Source and Gate-Drain capacitance would identify Source and Drain or a symmetrical J-FET reliably, but the Tester's circuit doesn't support that. It would require a DC bias and an AC based capacitance measurement.

Ohh  :palm:

Its another feature that I miss took as a bug or error, oops.

P.S. I am not sure why but 1.24m seems snappier to me than 1.12k @8MHz.  Can't wait to see how it will fly with 16MHz xtal.

Thanks for the explanation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 10, 2016, 01:22:33 am
A pack of 16MHz crystals came today.  Replace the 8 for 16 on my Color-kit AY-AT tester.  The holes were a biatch to clean out for the new crystal.

When I plugged in the battery, the tester started up just fine.  It seem to work normally with 8MHz fw build.  Feels faster refresh/test times.

Next, I've flashed a 16MHz fw but not seeing any difference  from 8MHz fw:-//.

Am I missing something?

Can I test the crystals with the tester?

Fuses are set to F7/D9/04.  I know some people set efuse to 0xfc, but my atmega can't take that, 0x04 works.

Update:
After more testing, with 8MHz fw and 16MHz xtal, the capacitance test values are doubled.  With 16MHz fw they are reported correctly  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 10, 2016, 02:51:21 am
Compiled 1.12k svn690 with xtal test and flashed it.  The original 8MHz crystal is detected as 8MHz exactly.  The ones I got today read as 14.6342KHz but sometimes not detected.  Is this limitations of tester or did I get crap crystals?
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 10, 2016, 03:57:10 am
I've got a MK-328 on it's way from HK, can't wait to have a play with it.

One question I have though, does anyone know where I can buy a AVR-ICSP 8 Pin cable to fit the Mini Pro TL866A? rather than knocking one up,
I would use this quite often and wondering if there is an off the shelf cable, buying the bits to make a cable costs more than buying a USBASP!
Title: Re: $20 LCR ESR Transistor checker project Stickey needed, where do I start?
Post by: jh15 on September 10, 2016, 04:11:12 am
thousands of posts, where and what do I buy?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 10, 2016, 04:30:07 am
Compiled 1.12k svn690 with xtal test and flashed it.  The original 8MHz crystal is detected as 8MHz exactly.  The ones I got today read as 14.6342KHz but sometimes not detected.  Is this limitations of tester or did I get crap crystals?

the crystal test is limited to about 12MHz, you cant test crystals running as fast or faster than the tester.
the 16MHz crystal makes the cap tests more accurate because of faster sampling though :)

so what did you NOT enable??
i couldnt build a hex for AY-AT with the crystal test without running out of room!
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 10, 2016, 04:49:33 am
stj,


Code: [Select]

CFLAGS += -DFONT_5X8
#CFLAGS += -DFONT_8X12thin
CFLAGS += -DWITH_XTAL
#CFLAGS += -DWITH_UART

Title: Re: $20 LCR ESR Transistor checker project Stickey needed, where do I start?
Post by: flywheelz on September 10, 2016, 05:08:39 am
thousands of posts, where and what do I buy?

Thousands of clones testers, to each his own.  Not knowing your need, I will list a few.  There are kits or already built versions.  Buy where you trust and price you like.
Well known as Banggood version
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)

Highly regarded as a nice choice GM328R.
http://www.ebay.co.uk/itm/331873741389 (http://www.ebay.co.uk/itm/331873741389)

Already built unit Nice case, zif board, 3 test clips, very good for bench/field use
http://www.banggood.com/MK-328-Transistor-Tester-Capacitor-ESR-Inductance-Resistor-Meter-LCR-NPN-PNP-MOS-p-1010347.html (http://www.banggood.com/MK-328-Transistor-Tester-Capacitor-ESR-Inductance-Resistor-Meter-LCR-NPN-PNP-MOS-p-1010347.html)

Fancy multi colored custom firmware, only one does higher voltage zener test,  Note: No multi color open-source firmware for this model
http://www.ebay.com/itm/2016-Transistor-Tester-TFT-Diode-Triode-Capacitance-Meter-LCR-ESR-NPN-PNP-MOSFET-/182170556129?hash=item2a6a3616e1:g:Ep8AAOSwnNBXX9D9 (http://www.ebay.com/itm/2016-Transistor-Tester-TFT-Diode-Triode-Capacitance-Meter-LCR-ESR-NPN-PNP-MOSFET-/182170556129?hash=item2a6a3616e1:g:Ep8AAOSwnNBXX9D9)

Russians favorite
http://www.ebay.com/itm/12864-Mega328-ESR-Transistor-Resistor-Diode-Capacitor-Mosfet-Tester-w-Test-hook-/321963237498?hash=item4af681207a:g:sBMAAOSwa-dWhWzn (http://www.ebay.com/itm/12864-Mega328-ESR-Transistor-Resistor-Diode-Capacitor-Mosfet-Tester-w-Test-hook-/321963237498?hash=item4af681207a:g:sBMAAOSwa-dWhWzn)

I purchased this one.  Color lcd AY-AT, slowish refresh rate, kit has some diode array input protection but this seller smds are not soldered, some other sellers got smds soldered already.
http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.56.J7yA7x (http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.56.J7yA7x)


Lately, some kits arrive with blank chips so you have to flash open source firmware  yourself.

Must read, all you ever wanted to know, the birth and the evelution of the infamous transistor tester and more
ttester.pdf manual (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jh15 on September 10, 2016, 05:36:34 am
Thank you, I have one of these, years ago didn't remember details, and wanted to figure it out, or buy another that I can trust.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 10, 2016, 05:39:06 am
narrow down your choice by saying if you want it ready-built, or if you want a kit.

if a kit, it's down to the banggood, the GM328r and the AY-AT
because you want the rotary encoder with it.

the AY-AT has the better display.
the banggood has an optional case - although that may be useable with the others with a bit of modding.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jh15 on September 10, 2016, 05:46:52 am
Great, plus I wanted to buy from the designer's source, wasn't sure if he was in the forum long ago.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 10, 2016, 08:48:16 am
Great, plus I wanted to buy from the designer's source, wasn't sure if he was in the forum long ago.

tough,
the original designer only had a 2line display and never made a comercial product.
and he is not on this forum, he is here:
https://www.mikrocontroller.net/topic/248078 (https://www.mikrocontroller.net/topic/248078)
and he based his on an even older design.
(it's called evolution.)
the chinese are the ones that adapted it for a graphic display, and then to colour.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 10, 2016, 09:23:22 am
I've got a MK-328 on it's way from HK, can't wait to have a play with it.

One question I have though, does anyone know where I can buy a AVR-ICSP 6 Pin cable to fit the Mini Pro TL866A? rather than knocking one up,
I would use this quite often and wondering if there is an off the shelf cable, buying the bits to make a cable costs more than buying a USBASP!

I have this tester too but mine does not have the conncetion or the hole in the case to fit the 6 pin lead but i could mod it if i wanted too but too programme my ic all i was doing was to remove the atmega 328p and flash the chip using the socket on the programmer which did work fine you just have to be carefull of the ic pins. I have not managed to find the lead hence have not done the mod to the cse etc i have brought a usbap and wired a header on to the ic pins which does the job just fine too.
Title: Re: $20 LCR ESR Transistor checker project Stickey needed, where do I start?
Post by: roli_bark on September 10, 2016, 09:43:20 am
I purchased this one.  Color lcd AY-AT, slowish refresh rate, kit has input protection but this one smds are not soldered
http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.56.J7yA7x (http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.56.J7yA7x)
Same from eBay - currently for a little cheaper price:
http://www.ebay.com/itm/2016-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator-/322186520645?var=&hash=item4b03d02845:m:m79XwjPQdDgykYr95zU8Nxw (http://www.ebay.com/itm/2016-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator-/322186520645?var=&hash=item4b03d02845:m:m79XwjPQdDgykYr95zU8Nxw)

Or even this:
http://www.ebay.com/itm/GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM-Signal-Generator-U3B6/391493964754?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D38828%26meid%3D7ef3a27bb0944d19a5135100595df01c%26pid%3D100005%26rk%3D4%26rkt%3D6%26sd%3D322186520645 (http://www.ebay.com/itm/GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM-Signal-Generator-U3B6/391493964754?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D38828%26meid%3D7ef3a27bb0944d19a5135100595df01c%26pid%3D100005%26rk%3D4%26rkt%3D6%26sd%3D322186520645)
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 10, 2016, 10:10:55 am
Beware that although this AY-AT kit comes with an optional external Supply Adapter connector (which is good to have), is seems to come WITHOUT the 9v Battery connector !
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2016, 10:16:42 am
Great, plus I wanted to buy from the designer's source, wasn't sure if he was in the forum long ago.

tough,
the original designer only had a 2line display and never made a comercial product.
and he is not on this forum, he is here:
https://www.mikrocontroller.net/topic/248078 (https://www.mikrocontroller.net/topic/248078)

You haven't read all posts of this thread  >:D Karl-Heinz has an account for this forum too, but isn't a regular poster.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 10, 2016, 12:14:16 pm
Beware that although this AY-AT kit comes with an optional external Supply Adapter connector (which is good to have), is seems to come WITHOUT the 9v Battery connector !

the one i got came with the battery clip.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 10, 2016, 12:52:55 pm
tough,
the original designer only had a 2line display and never made a comercial product.
and he is not on this forum, he is here:
https://www.mikrocontroller.net/topic/248078 (https://www.mikrocontroller.net/topic/248078)
and he based his on an even older design.
(it's called evolution.)
the chinese are the ones that adapted it for a graphic display, and then to colour.

Yes, the original project (by Markus Frejek) uses only two-line text LCD display. But an improved version of tester (Karl-Heinz Kübbeler) allows the use of graphic display and proof of this is a software repository and information in the manual (I recommend carefully studied the manual).
More or less all the chinese versions and clones are based on the software by Karl-Heinz Kübbeler.

Markus Frejek
http://www.mikrocontroller.net/articles/AVR-Transistortester (http://www.mikrocontroller.net/articles/AVR-Transistortester)

Karl-Heinz Kübbeler (kubi48)
http://www.mikrocontroller.net/articles/AVR_Transistortester (http://www.mikrocontroller.net/articles/AVR_Transistortester)
Karl-Heinz Kübbeler (kubi48) - forum
https://www.mikrocontroller.net/topic/248078 (https://www.mikrocontroller.net/topic/248078)

Markusa Reschke (madires) - alternative software
http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (http://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 10, 2016, 02:34:55 pm
sorry, but i do follow that forum.
the chinese added the graphic display on comercial products FIRST,
Karl Heinz added compatable drivers / fonts to the public code afterwards.

just like the chinese added colour before it was added to the public code.
infact the public code still does not have code for multi-colour images like the chinese TC-1 etc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2016, 03:31:03 pm
And none of the Chinese clone vendors who modified the open source firmware released or submitted their changes. No hints about the project's web page, no credits, no documentation and so on. :--
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 10, 2016, 04:03:34 pm
For whatever it's worth, here's the [pretty lousy] manual for the AY-AT kit:
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 10, 2016, 08:40:13 pm
The Chinese cloners also had to design the interface for the display, and I think they actually did a fairly decent job of it with their "M-Tester." Too bad they decided not to share.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 10, 2016, 08:48:06 pm
Yeah the M-Tester/TC1 looks very interesting, have been keeping an eye on eBay to get one to mess around with.
These use the Atmel 324, the full Colour display looks great! shame none of the other so called "Colour" versions have this chip, though I guess this is fairly new so hoping a few more clones pop up.



The Chinese cloners also had to design the interface for the display, and I think they actually did a fairly decent job of it with their "M-Tester." Too bad they decided not to share.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Quarlo Klobrigney on September 11, 2016, 02:33:08 am
For whatever it's worth, here's the [pretty lousy] manual for the AY-AT kit:
And in spelling but not grammar corrected Chingrish, here is a PDF of the doc file:
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 11, 2016, 05:46:21 am
and now FISH has a new colour model!!

http://www.ebay.com/itm/222210243721 (http://www.ebay.com/itm/222210243721)

it looks pretty nice, good price too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 11, 2016, 05:58:59 am
and now FISH has a new colour model!!

http://www.ebay.com/itm/222210243721 (http://www.ebay.com/itm/222210243721)

it looks pretty nice, good price too.
Just 'cosmetic' changes. All of the same ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: tom666 on September 11, 2016, 09:21:42 am
Please, don't forget that an important feature of the original concept is easy reproducibility in the amateur conditions with the !! freely available source code !! (with uses of the classic THT or SMD components - see attached pictures). Color display does not bring any added value! Serve only to increase sales.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 11, 2016, 09:50:49 am
colour display has better contrast actually, and also a higher resolution.

the fish unit is nice because the zif socket plugs in - and they do get worn.
also it looks like it may have a high voltage generator in it for testing zeners even though it's not mentioned.

i look forward to seeing what mcu they use - if it's got more than 32k of flash then it's automatically the best available so far.
even if it's only 32k, if they used a 44pin package over the 32pin one then it would probably be upgradeable.
i think the TC-1 is using a 44pin package.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 11, 2016, 12:56:21 pm
I'd like to test the function generator on mine but I wonder about something I read in the manual.


From the manual :"The frequency output is done with the 680 resistor at measurement port TP2"
So signal is TP2 and ground at TP1 but what about that resistor?

Should I attach this resistor between the scope and the tester or it's just that the tester has a 680r resistor at TP2 ?!
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 11, 2016, 01:18:26 pm
the tester has a 680ohm resistor inline with the signal that will limit the output current - that's what it means.

feel free to poke it with a scope, i already proded one with a frequency counter without any issues. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 11, 2016, 01:25:03 pm
colour display has better contrast actually, and also a higher resolution.

the fish unit is nice because the zif socket plugs in - and they do get worn.
also it looks like it may have a high voltage generator in it for testing zeners even though it's not mentioned.

i look forward to seeing what mcu they use - if it's got more than 32k of flash then it's automatically the best available so far.
even if it's only 32k, if they used a 44pin package over the 32pin one then it would probably be upgradeable.
i think the TC-1 is using a 44pin package.

TC-1 uses Atmega 324
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on September 11, 2016, 01:42:24 pm
Quote
Color display does not bring any added value!
They do add some value if you are using color wires that clip to your device-under-test.  You get to know which pin is what easily.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 11, 2016, 02:21:31 pm
Quote
Color display does not bring any added value!
They do add some value if you are using color wires that clip to your device-under-test.  You get to know which pin is what easily.

I agree with the comments regarding the "Full Colour" display versions, itching to get my hands on one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 11, 2016, 03:52:07 pm
Quote
Color display does not bring any added value!
They do add some value if you are using color wires that clip to your device-under-test.  You get to know which pin is what easily.

It should be fairly simple to add color coding for the probe/pin numbers. Any more votes for that neat idea?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 11, 2016, 04:11:36 pm
You got my vote for colored pins. I already soldered 3 pin header and received
 some push clips to add to my AY-AT tester to make some external leads.

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 11, 2016, 04:13:16 pm
It should be fairly simple to add color coding for the probe/pin numbers. Any more votes for that neat idea?
Nice idea.
But a more important question is whether there exists a 'config.h' (or other way to config a repository version) for the AY-AT and/or Fish full color kit ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 11, 2016, 04:42:12 pm
I've started a text file with descriptions for the various clones:

Code: [Select]
DIY Kit "AY-AT"
- with ST7735 color LCD module
- provided by flywheelz@EEVBlog


LCD module:

#define LCD_ST7735_SPI
#define LCD_COLOR                       /* color graphic display */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RES          PD4            /* port pin used for /RESX */
#define LCD_CS           PD5            /* port pin used for /CSX (optional) */
#define LCD_DC           PD1            /* port pin used for D/CX */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SDA          PD3            /* port pin used for SDA */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       160            /* number of vertical dots */
#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_ROTATE                      /* switch X and Y (rotate by 90°) */
#define FONT_10X16_H                    /* 10x16 font, horizontally aligned */
#define SYMBOLS_24X24_H                 /* 24x24 symbols, horizontally aligned */


Rotary Encoder:

#define ENCODER_A        PD1       /* rotary encoder A signal */
#define ENCODER_B        PD3       /* rotary encoder B signal */

It already lists:
- DIY Kit "AY-AT"
- M12864 DIY Transistor Tester
- Chinese clone T3/T4

If you got any other clone, please send me your settings for the m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 11, 2016, 05:13:55 pm
I don't understand:
Is this text file in a preliminary stage of gathering info of various clone out there,
or already part of some config parameters section that exists somewhere in the repository ?
If so, where ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 11, 2016, 05:36:07 pm
It's the first, just a list of required settings for some clones. It will be included in the next release.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 11, 2016, 05:47:40 pm
Nice, great effort !
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 11, 2016, 10:47:27 pm
Quote
Color display does not bring any added value!
They do add some value if you are using color wires that clip to your device-under-test.  You get to know which pin is what easily.

It should be fairly simple to add color coding for the probe/pin numbers. Any more votes for that neat idea?

I don't see why not. It would be a plus to balance out the slow refresh. BTW, almost by accident found a video showing the difference between HW SPI and bitbanging just to show that the screen itself is not really as slow as it seems to be:
https://www.youtube.com/watch?v=-eTXR8jsXOI (https://www.youtube.com/watch?v=-eTXR8jsXOI)

I've started a text file with descriptions for the various clones:

LOL, there goes my idea of a database. But something like this is long overdue, so I'm glad to see it anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 12, 2016, 06:40:13 am
I see that the Chinese AY-AT kit provides additional functions besides its being an LCR meter:
For example measure Temp (with the DS18B20 sensor), IR Decoding, and may be more.

Are these implemented in the repository ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 12, 2016, 08:51:09 am
It's the first, just a list of required settings for some clones. It will be included in the next release.
A wild wishful thinking: Any thoughts about a TFT 3.2" 240*320 Touch display option?

http://www.ebay.com/itm/3-2-inch-TFT-LCD-Display-Module-Touch-Panel-SD-Card-Cage-for-Arduino/171988190464?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20131003132420%26meid%3D763d8e3cb52e42cb8ab583bb834faf22%26pid%3D100005%26rk%3D1%26rkt%3D6%26sd%3D271201097446 (http://www.ebay.com/itm/3-2-inch-TFT-LCD-Display-Module-Touch-Panel-SD-Card-Cage-for-Arduino/171988190464?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20131003132420%26meid%3D763d8e3cb52e42cb8ab583bb834faf22%26pid%3D100005%26rk%3D1%26rkt%3D6%26sd%3D271201097446)

http://www.uctronics.com/download/lcd/3.2tft-(ssd1289).zip
 (http://www.uctronics.com/download/lcd/3.2tft-(ssd1289).zip)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 12, 2016, 10:39:08 am
It should be fairly simple to add color coding for the probe/pin numbers. Any more votes for that neat idea?

I don't see why not. It would be a plus to balance out the slow refresh. BTW, almost by accident found a video showing the difference between HW SPI and bitbanging just to show that the screen itself is not really as slow as it seems to be:

Yep, that's one reason why the ATmega644/1284 circuit has the hardware SPI reserved for the display and additional SPI based options. A lot of thought went into a port pin plan supporting several variations, options and future extensions. One USART and the I2C (TWI) are also reserved.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 12, 2016, 10:44:15 am
I see that the Chinese AY-AT kit provides additional functions besides its being an LCR meter:
For example measure Temp (with the DS18B20 sensor), IR Decoding, and may be more.

Are these implemented in the repository ?

The m-firmware has an IR decoder (requires a TSOP or similar IR receiver module) and supports following protocols:
  - JVC
  - Kaseikyo (aka Japanese Code, 48 bit)
  - Matsushita/Emerson
  - Motorola
  - NEC (standard & extended)
  - RC-5 (standard)
  - RC-6 (standard)
  - Samsung (32 bit Toshiba)
  - Sharp
  - Sony SIRC (12, 15 & 20 bit)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 12, 2016, 11:33:14 am
A wild wishful thinking: Any thoughts about a TFT 3.2" 240*320 Touch display option?

The m-firmware already supports the ILI9341/9342, and the touch screen (ADS7843) is on the to-do list, but has to wait until I've finished my 644/1284 dev board, because we need some extra I/O pins.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 12, 2016, 12:22:29 pm
Guys at the moment in using stj v2 firmware on my tester which is working fine and im gratefull for his time getting my tester and others working ,but as i have two of these testers is there anyone else who has made firmware for these that i can try this is the tester i have its 16 mhz.
http://www.ebay.co.uk/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/331873741389?hash=item4d45376a4d:g:rrsAAOSwtJZXU~VA (http://www.ebay.co.uk/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/331873741389?hash=item4d45376a4d:g:rrsAAOSwtJZXU~VA)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on September 12, 2016, 02:21:50 pm
Hi.

I have a LCR-T4 like this:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867)

I have compiled the latest version of the software (mega328_T3_T4_st7565 R690) using the "Programmers Notepad [WinAVR]" and the option #CFLAGS + = -DPULLUP_DISABLE and works really well.

I read that in this variant Chinese can not use the frequency meter incompatibility with the screen.

¿ How I can compile the firmware without the option "Frequency meter" in the menú ?.

Thanks and regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 12, 2016, 03:25:54 pm
The m-firmware has an IR decoder (requires a TSOP or similar IR receiver module) and supports following
Thanks for IR update.
- Is there a config parameter that enables/disables the IR decoder functionality ?
- Also, is there any readme file that describes the various variants in the k-firmware dir ("trunk") - e.g.:
arduino_m2560
arduino_uno
default
dep
ILI9163
mega168_1.9V
mega168_3.3V
mega168_strip_grid
mega328
mega328_1.9V
mega328_2X16_menu
mega328_3.3V
mega328_color_kit
mega328_dogm
mega328_fish8840
mega328_fish8840_OC
mega328_GM328
mega328_PCF8812
mega328_PCF8814
mega328_ssd1306I2C
mega328_ssd1306SPI
mega328_st7108
mega328_st7565
mega328_st7565_kit
mega328_st7920
mega328_strip_grid
mega328_strip_grid_dogm
mega328_T3_T4_st7565
mega328_T5_st7565
mega328_wei_st7565
mega644_LCD2004
mega644_ssd1306I2C
mega8
ST7735
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 12, 2016, 03:37:04 pm
AFAIK, you can't disable the frequency counter in the k-firmware when you've enabled the menu. The only way would be to change function_menu.c.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 12, 2016, 03:49:56 pm
Thanks for IR update.
- Is there a config parameter that enables/disables the IR decoder functionality ?
- Also, is there any readme file that describes the various variants in the m-firmware dir ("trunk") - e.g.:

To enable the IR decoder in the m-firmware edit config.h (uncomment "#define SW_IR_RECEIVER"). A few posts ago I've mentioned, that the next release wil include a text file with a list of settings for different clones. At the moment it includes only three clones. Since I don't buy every new clone, I'll need your help to add other clones too. If someone got a clone and is running the m-firmware, please send me your settings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on September 12, 2016, 04:10:37 pm
AFAIK, you can't disable the frequency counter in the k-firmware when you've enabled the menu. The only way would be to change function_menu.c.

This is beyond my limited knowledge.

Better leave it alone and just do not use that function.

Thank you very much and greetings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 12, 2016, 04:25:01 pm
...A few posts ago I've mentioned, that the next release wil include a text file with a list of settings for different clones. At the moment it includes only three clones. Since I don't buy every new clone, I'll need your help to add other clones too. If someone got a clone and is running the m-firmware, please send me your settings.
Thanks for the heads up.
My question was more on a need for a readme file for the variants in the k-firmware dir ("trunk").
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 13, 2016, 12:04:27 pm
MK-328 Has just arrived with me from China,

Really impressed with this so far, identified a load of ancient transistors and such. I ordered it with the additional PCB with ZIF socket, best of both worlds with leads and a socket.

Firmware states 1.12k but doesn't give actual version, have ordered a 16MHz crystal to fit to it, might fit a rotary encoder but not sure yet.

Just wondering what the correct latest firmware for this model is and whether it's worth fitting the 16MHz crystal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 13, 2016, 12:41:46 pm
anybody with an AY-AT kit, may be interested in what i just found.
http://www.ebay.co.uk/itm/182242949338 (http://www.ebay.co.uk/itm/182242949338)

 8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 13, 2016, 01:35:18 pm
MK-328 Has just arrived with me from China,

Really impressed with this so far, identified a load of ancient transistors and such. I ordered it with the additional PCB with ZIF socket, best of both worlds with leads and a socket.

Firmware states 1.12k but doesn't give actual version, have ordered a 16MHz crystal to fit to it, might fit a rotary encoder but not sure yet.

Just wondering what the correct latest firmware for this model is and whether it's worth fitting the 16MHz crystal.

1.12k is the latest version, but I assume you mean the revision ;) You can find the latest revision at https://github.com/svn2github/transistortester/tree/master/Software/trunk . The 16MHz crystal helps with the capacitance and inductance measurements, any frequency stuff and color displays. And if like to try a 20MHz crystal, there's the m-firmware. 8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 13, 2016, 02:14:47 pm
MK-328 Has just arrived with me from China,

Really impressed with this so far, identified a load of ancient transistors and such. I ordered it with the additional PCB with ZIF socket, best of both worlds with leads and a socket.

Firmware states 1.12k but doesn't give actual version, have ordered a 16MHz crystal to fit to it, might fit a rotary encoder but not sure yet.

Just wondering what the correct latest firmware for this model is and whether it's worth fitting the 16MHz crystal.

1.12k is the latest version, but I assume you mean the revision ;) You can find the latest revision at https://github.com/svn2github/transistortester/tree/master/Software/trunk . The 16MHz crystal helps with the capacitance and inductance measurements, any frequency stuff and color displays. And if like to try a 20MHz crystal, there's the m-firmware. 8)

Thanks for the reply :)

Yeah it doesn't state the revision, ah 20MHz sounds interesting will have a look for one and also the M-Firmware, I only have 25MHz crystals here at the moment so ordered a 16MHz, will get a 20MHz in too.
With the calibration, does it have to be 100nf or anything above? just looking for a cap here with 5-10% tolerance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 13, 2016, 02:21:39 pm
anybody with an AY-AT kit, may be interested in what i just found.
http://www.ebay.co.uk/itm/182242949338 (http://www.ebay.co.uk/itm/182242949338)

 8)
Nice. But the 9v battery looks like it's lying loose beneath...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on September 13, 2016, 02:25:22 pm
anybody with an AY-AT kit, may be interested in what i just found.
http://www.ebay.co.uk/itm/182242949338 (http://www.ebay.co.uk/itm/182242949338)

 8)

Yes, ordered that one and it looks nice.
one problem the handle of the zif-socket isn't accessible when it is closed,
also you can't use the SMD pads.
So I made an cut out in the case at the top where the SMD pad is and
also in het richt panel. Than it is OK.
BTW perfect fitting of het parts and looks nice.
I use an AC adapter, so the battery is no problem for me.
Connector for AC adapter fits perfect.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 13, 2016, 02:48:15 pm
anybody with an AY-AT kit, may be interested in what i just found.
http://www.ebay.co.uk/itm/182242949338 (http://www.ebay.co.uk/itm/182242949338)

 8)

Yes, ordered that one and it looks nice.
one problem the handle of the zif-socket isn't accessible when it is closed,
also you can't use the SMD pads.
So I made an cut out in the case at the top where the SMD pad is and
also in het richt panel. Than it is OK.
BTW perfect fitting of het parts and looks nice.
I use an AC adapter, so the battery is no problem for me.
Connector for AC adapter fits perfect.

Nicely done!

What did you use to get a nice cut?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 13, 2016, 03:30:31 pm
i would just cut the knob off of the socket lever and extend the shaft a bit with some tubing.

it looks like it has a divider to hold the battery away from the pcb btw.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on September 13, 2016, 04:23:41 pm
@ flywheelz
I used an mini iron-saw and a file to clean up.

@ stj
Yes, there is room for an battery,
the pcb has connections for it.
To access the battery you have to unscrew the bottomplate,
four screws.

"i would just cut the knob off of the socket lever and extend the shaft a bit with some tubing."
Yes is possible,
but no access to SMD pads then.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 13, 2016, 04:44:52 pm
With the calibration, does it have to be 100nf or anything above? just looking for a cap here with 5-10% tolerance.

It doesn't have to be a 100nF cap, any film cap between 100nF and 1µF is fine (larger values work too). The tolerance doesn't matter either.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 13, 2016, 07:44:39 pm
I have a bit of a problem I was wondering if help might attract :0 lol.

Yeah I bought one of these kits before I found out much about them.

I got this kit from ebay with no instructions on assembly. I suppose I could figure it out from a schematic but I would prefer if someone could point me too a drawing of parts placement or perhaps kit instructions?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 13, 2016, 08:08:32 pm
I have a bit of a problem I was wondering if help might attract :0 lol.

Yeah I bought one of these kits before I found out much about them.

I got this kit from ebay with no instructions on assembly. I suppose I could figure it out from a schematic but I would prefer if someone could point me too a drawing of parts placement or perhaps kit instructions?

i have two of these testers if you read back a few pages stj helped me with the parts list and what went where etc its all in this thread including the firmware too as most of these tester have come with no firmware anything you need too know just ask

edit here you go should help you
----------------------------------------
r1 - 680r sensing circuit
r2 - 470k sensing circuit
r3 - 680r sensing circuit
r4 - 470k sensing circuit
r5 - 680r sensing circuit
r6 - 470k sensing circuit
r7 - 10k reset pullup
r8 - 33k power control
r9 - 3k3 power control
r10 - 27k
r11 - 100k (says r1 but is next to r10)
r12 - 10k voltage divider for battery sense
r13 - 3k3 voltage divider for battery sense
r14 - 560r display related - led current limit
r15 - 27k
r16 - 0r jumper for AVCC
r17 - 2k2 from tl431 to vcc
r18 - 1k rotary encoder current limit
r19 - 1k rotary encoder current limit
r20 - 10k rotary encoder pullup
r21 - 10k rotary encoder pullup
r22 - 470r frequency input dropper
r23 - 10k frequency input voltage divider
r24 - 10k frequency input voltage divider

rv1 - 10k preset frequency input voltage divider

u3 = tl431

q1 - 4673 (bc557c)
q2 - c945 (bc547)
q3 - c945 (bc547)

c1 - 22pf for crystal
c2 - 22pf for crystal
c3 - 100nf
c4 - 10nf
c5 - 10uf 16v
c6 - 10uf 16v
c7 - 100nf
c8 - 100nf
c9 - 100n frequency input DC blocker

and post 349 in this thread has a good picture you can zoom in on and see the colours of the resistors if needed
http://www.badcaps.net/forum/showthread.php?t=50720&highlight=esr+tester&page=18 (http://www.badcaps.net/forum/showthread.php?t=50720&highlight=esr+tester&page=18)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheOnlyDocc on September 13, 2016, 08:52:26 pm
Hello,
a few days ago i ordered my first ESR Meter (http://www.ebay.de/itm/182153844649 (http://www.ebay.de/itm/182153844649) ) ~15€ inkl. case. Now i have read that it is possible to incrase the accuracy by changing the 8MHz crystall with a 16MHz one. But i do not know which new FW i have to use. Maybe someone can give me a hint. And if someone have any other helpfull tips i am open for informations. Hopefully the Kit will arrive in the next few weeks. So now i have the time to get parts (like the new 16MHz crystall) if needed.
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 13, 2016, 09:01:40 pm
vinceroger

Hey thanks! My first post and made to feel welcome thank you.

I'm sorry I had to bother I thought I had searched pretty well and had also given up on google fu. Thanks again

Monroe King
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 13, 2016, 09:33:09 pm
Hello,
a few days ago i ordered my first ESR Meter (http://www.ebay.de/itm/182153844649 (http://www.ebay.de/itm/182153844649) ) ~15€ inkl. case. Now i have read that it is possible to incrase the accuracy by changing the 8MHz crystall with a 16MHz one. But i do not know which new FW i have to use. Maybe someone can give me a hint. And if someone have any other helpfull tips i am open for informations. Hopefully the Kit will arrive in the next few weeks. So now i have the time to get parts (like the new 16MHz crystall) if needed.

that's the "AY-AT" kit - lots about it in previous posts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 13, 2016, 09:37:01 pm
vinceroger

Hey thanks! My first post and made to feel welcome thank you.

I'm sorry I had to bother I thought I had searched pretty well and had also given up on google fu. Thanks again

Monroe King

forget google,
use https://duckduckgo.com (https://duckduckgo.com)
and https://www.yandex.com/yandsearch? (https://www.yandex.com/yandsearch?)
and for chinese stuff: https://www.baidu.com (https://www.baidu.com)
:)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 13, 2016, 11:03:31 pm
Well I soldered up the board and plugged in the battery.

Pushed the test button and only the back light came on? I guess this means the 328 is not programmed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 14, 2016, 12:21:16 am
Well I soldered up the board and plugged in the battery.

Pushed the test button and only the back light came on? I guess this means the 328 is not programmed?

99.99% Yes.


Firmware, here. (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1021248/#msg1021248)


Program with Arduino, here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1021401/#msg1021401), or you can also use USBasp, but with command
Code: [Select]
avrdude -c USBasp -P usb -p m328p -e -U flash:w:TransistorTester.hex -U eeprom:w:TransistorTester.eep -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0x04:m
You could build simple programmer, here. (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg989880/?topicseen#msg989880)

Or perhaps you have TL866A which also can be used.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 14, 2016, 12:29:01 am
MAJOR bummer!

Let me see what programmers I have: Crap

lol
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 14, 2016, 04:58:40 am
Hello,
a few days ago i ordered my first ESR Meter (http://www.ebay.de/itm/182153844649 (http://www.ebay.de/itm/182153844649) ) ~15€ inkl. case. Now i have read that it is possible to incrase the accuracy by changing the 8MHz crystall with a 16MHz one. But i do not know which new FW i have to use. Maybe someone can give me a hint. And if someone have any other helpfull tips i am open for informations. Hopefully the Kit will arrive in the next few weeks. So now i have the time to get parts (like the new 16MHz crystall) if needed.
You can start here:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1016572/#msg1016572 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1016572/#msg1016572)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jleg on September 14, 2016, 08:44:24 am
i just also got a AY-AT kit - it came with a similar "manual" which already has been posted here, and additionally with a schematic - i added it below...

Btw, last words in that "manual" are

Quote
At last: For more information about the Transistortester, please visit http://www.mikrocontroller.net/articles/AVR-Transistortester (http://www.mikrocontroller.net/articles/AVR-Transistortester)

 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 14, 2016, 08:46:10 am
Well I soldered up the board and plugged in the battery.

Pushed the test button and only the back light came on? I guess this means the 328 is not programmed?

have you got a link to the one you brought from ebay as i emailed the seller and i know a few others have regarding no firmware being on these atmega328p ics if its the same seller im suprised they havnt stopped selling them as they did seem concerned when mentioned about the non firmware issue.

A good upgrade for these meters too once you get it working is swop the crystal to a 16 mhz one with the correct firmware too as it seems a lot more accurate then.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 14, 2016, 12:11:30 pm
Here is a link http://www.ebay.com/itm/331873736187?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/331873736187?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

I guess I might as well try the 16mhz now that I have to load firmware anyway Gezzzzzz.

Monroe
 Team Prometheus
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 14, 2016, 12:29:27 pm
Here is a link http://www.ebay.com/itm/331873736187?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/331873736187?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

I guess I might as well try the 16mhz now that I have to load firmware anyway Gezzzzzz.

Monroe
 Team Prometheus

Yes thats the same seller maybe worth you too sending them a email too say theres no firmware on the ic so basically you cant use it. (well you can once you upload the firmware etc ) have you got a programmer?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 14, 2016, 01:51:17 pm
I have sent a scathing email to the seller. I would not have minded so much if it had stated that the chip was not programmed in the ad.

Yeah, I have some programmers around here just didn't want to dig one out for this project.

Didn't want to figure out what IDE to use or any of that time consuming MESS!

I only program chips when I absolutely have too.

I'll get on it here in a few-

Hey if it had not been for you guy's I'd have been out of luck! So would this seller.

Monroe   
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 14, 2016, 03:07:54 pm
you wont need an IDE / compiler, we can give you the hex.
all you need is AVRdude programming software.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 14, 2016, 04:00:20 pm
"you wont need an IDE / compiler"

Uh hu  that sounds familiar :)

Ok I've got a USBTinyISP haven't used it since windblows 10 came out. Blew that off went for the XP machine in the shop I think the little programmer seems to work.

Now I gotta break out the soldering iron figure out what pins to hook up to. Looks like you guys just solder the header to the back side of the chip and power the board is this correct?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 14, 2016, 04:07:17 pm
"you wont need an IDE / compiler"

Uh hu  that sounds familiar :)

Ok I've got a USBTinyISP haven't used it since windblows 10 came out. Blew that off went for the XP machine in the shop I think the little programmer seems to work.

Now I gotta break out the soldering iron figure out what pins to hook up to. Looks like you guys just solder the header to the back side of the chip and power the board is this correct?

this may help
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 14, 2016, 04:49:02 pm
Looks like you guys just solder the header to the back side of the chip and power the board is this correct?

Thats what I did.  As soon as the programmer is plugged in the usb it will provide 5v to the testers and lcd back light will go on. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 14, 2016, 09:29:15 pm
Want to update you guys, 

When I was putting my AY-AT kit, I found out that I installed the protection 6-pin diode pack suppressor backwards due to poor markings on the chip causing VCC short GND  (credit: stj).  After removing the suppressor, the tester started working.  I lost the original suppressor and the replacement just arrived. 

Installed the replacement V05 suppressor without issues.  On first power-on, the LED turned on, tester enters the menu , then showed Bat. 8.3V OK, flashing Vext=0mV.  |O  I tried disconnecting the battery few times with no help.  I decided to remove the LCD.  As I was lifting the top right corner of the LCD the tester went into Testing...  I pushed the LCD back down and the tester is still working fine.   :wtf:  I am not sure what really happened.  The good thing is its working now :popcorn:

Thank you all.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 15, 2016, 12:36:05 am
Progress but no cigar yet :(

I flashed the 328 with the 8Mhz firmware from the zip file "GM328x ESR tester (SVN684) - v2.zip" vinceroger so kindly provided all I had to do was change usbasp to usbtiny and the flash seemed fine.

I connected the battery and hit the test button and the display and the led came on after about 5-10 seconds the display went dark on all pixels (backlight stayed on) and then a few seconds later the screen started flashing at 5-10hz on and off as well as the led.

I checked my solder joints no joy.

Any thoughts?

Monroe 
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 15, 2016, 12:48:13 am
Did you set the fuses and no errors in process?

Code: [Select]
-U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0x04:m
edit: Is the battery good under load?

edit2:  Did you see any image?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 15, 2016, 01:31:33 am
Battery good

No image

Here is the screenshot
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 15, 2016, 01:48:55 am
Fuses are wrong, you need to set, inverted on avrdude config file I believe.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 15, 2016, 04:36:57 am
...On first power-on, the LED turned on, tester enters the menu , then showed Bat. 8.3V OK, flashing Vext=0mV.  |O  I tried disconnecting the battery few times with no help.  I decided to remove the LCD.  As I was lifting the top right corner of the LCD the tester went into Testing...  I pushed the LCD back down and the tester is still working fine.   :wtf:  I am not sure what really happened.  The good thing is its working now :popcorn:
Looks like some of your solder joints is cold.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 15, 2016, 05:03:13 am
Battery good

No image

Here is the screenshot

Why are there backslashes on some of the avrdude options, remove them and try again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 15, 2016, 05:16:18 am
roli_bark, good possibility. I've looked but could not find any.

Monroe, I don't  even see it programming the fuses.  And the ones its reporting are wrong.  Also, for atmega328p it the efuse should be "efuse:w:0x04:m", for atmega324p its efuse:w:0xfc:m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 15, 2016, 05:18:22 am
ignore "TheBay",

your using win10 probably, it has a keyboard buffer bug.
you need seperate strings to work around it.

Quote
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c USBasp -p m328p -U eeprom:w:TransistorTester.eep
avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m

btw, get a real operating system!
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 15, 2016, 05:25:27 am
ignore "TheBay",

your using win10 probably, it has a keyboard buffer bug.
you need seperate strings to work around it.

Quote
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c USBasp -p m328p --U eeprom:w:TransistorTester.eep
avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m


btw, get a real operating system!
Ignore me?

And line 2 you have --U should be -U.

Windows 10 is a real OS  :P

Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 15, 2016, 05:30:11 am
ignore "TheBay",

your using win10 probably, it has a keyboard buffer bug.
you need seperate strings to work around it.

Quote
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c USBasp -p m328p --U eeprom:w:TransistorTester.eep
avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m


btw, get a real operating system!
Ignore me?

And line 2 you have --U should be -U.

Windows 10 is a real OS  :P

well spotted on the double-,
but dont tell people to remove seperators, if they mess up the fusebits they can lock the chip.

as for 10 - yea right!  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 15, 2016, 05:36:05 am
ignore "TheBay",

your using win10 probably, it has a keyboard buffer bug.
you need seperate strings to work around it.

Quote
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c USBasp -p m328p --U eeprom:w:TransistorTester.eep
avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m


btw, get a real operating system!
Ignore me?

And line 2 you have --U should be -U.

Windows 10 is a real OS  :P

well spotted on the double-,
but dont tell people to remove seperators, if they mess up the fusebits they can lock the chip.

as for 10 - yea right!  :-DD

Depends where the separaters are, eprom and fuse's were not getting invoked.

Can't say I've had any issues with 10, it's given some things a new lease of life. Use 10 day to day but Linux for anything a bit more technical where it's a lot more flexible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 15, 2016, 05:51:17 am
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c USBasp -p m328p -U eeprom:w:TransistorTester.eep
avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m

I guess the order of these 3 lines is important.
BTW - how do I do that (dealing with 3 phases of programming the MCU) with the TL866 programmer ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 15, 2016, 06:04:09 am
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c USBasp -p m328p -U eeprom:w:TransistorTester.eep
avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m

I guess the order of these 3 lines is important.
BTW - how do I do that (dealing with 3 phases of programming the MCU) with the TL866 programmer ?

Easy, load the hex in to CODE and eep in to DATA, set fuse's correctly and flash  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 15, 2016, 06:34:58 am
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c USBasp -p m328p -U eeprom:w:TransistorTester.eep
avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m

I guess the order of these 3 lines is important.
BTW - how do I do that (dealing with 3 phases of programming the MCU) with the TL866 programmer ?

Easy, load the hex in to CODE and eep in to DATA, set fuse's correctly and flash  :-+
I guess that the eep file must be first converted to hex ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 15, 2016, 06:39:39 am
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c USBasp -p m328p -U eeprom:w:TransistorTester.eep
avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m

I guess the order of these 3 lines is important.
BTW - how do I do that (dealing with 3 phases of programming the MCU) with the TL866 programmer ?

Easy, load the hex in to CODE and eep in to DATA, set fuse's correctly and flash  :-+
I guess that the eep file must be first converted to hex ?

I remember reading somewhere, load it as Intel format.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 15, 2016, 07:04:51 am
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c USBasp -p m328p -U eeprom:w:TransistorTester.eep
avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m

I guess the order of these 3 lines is important.
BTW - how do I do that (dealing with 3 phases of programming the MCU) with the TL866 programmer ?

Easy, load the hex in to CODE and eep in to DATA, set fuse's correctly and flash  :-+
I guess that the eep file must be first converted to hex ?

I remember reading somewhere, load it as Intel format.

Intel format for both files, just load the Hex in to CODE and EEP in to DATA. Check under the Code and Data tabs to see if they have both loaded.
Found this screen shot of the fuses on this forum, not sure whether you are doing ICSP or Using the Socket, but select what is appropriate for you.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=197737;image)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 15, 2016, 08:12:23 am
Thought i'd open my MK-328 and put some pictures up.

Differences with mine are, Green PCB but seems decent quality, no EZM Studios logo on the casing or inside, but exactly the same PCB layout and components.
Ignore the hot snot on the terminals, I put that there.

About to fit a 16mhz Crystal and debating fitting a rotary encoder...

(http://i1086.photobucket.com/albums/j457/thebayuk/EEVblog/20160915_090631_zpsf2hrg1s1.jpg) (http://s1086.photobucket.com/user/thebayuk/media/EEVblog/20160915_090631_zpsf2hrg1s1.jpg.html)
(http://i1086.photobucket.com/albums/j457/thebayuk/EEVblog/20160915_090557_zpsivticxkj.jpg) (http://s1086.photobucket.com/user/thebayuk/media/EEVblog/20160915_090557_zpsivticxkj.jpg.html)
(http://i1086.photobucket.com/albums/j457/thebayuk/EEVblog/20160915_091037_zpsdqdkuod5.jpg) (http://s1086.photobucket.com/user/thebayuk/media/EEVblog/20160915_091037_zpsdqdkuod5.jpg.html)


Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 15, 2016, 08:20:29 am
Thank you guys. Now I do remember the TL866 option already mentioned in this long thread.

That looks like a very nice kit. Especially its built-in ICSP connector.
And when you upgrade to a 16Mhz clock, don't forget to change relevant fuses.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 15, 2016, 09:23:31 am
16MHz clock uses the same fuses, just different hex.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 15, 2016, 10:14:51 am
Battery good

No image

Here is the screenshot

I also had issues on windows 10 but run the three seperate commands as stj has posted they worked fine for me
avrdude -c USBasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c USBasp -p m328p -U eeprom:w:TransistorTester.eep
avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 15, 2016, 12:54:28 pm
Just fyi I'm using XP as I posted earlier. My old shop machine runs XP because a lot of stuff I use runs on XP I've  got machines running 10 and 7 I can dual boot to Ubuntu. I have an old Audigy card in that XP system I sometimes use to output audio signals for testing.

Ok so I guess the string for avrdude that comes in the zip file I mentioned is not set to burn the fuses I guess supposing the fuses where already set on a pre programed chip.

Anyways I'll look into it today- This tester better be worth it lol!

It could be something not set because I'm using USBTinyISP rather than USBasp I donno yet. Headed to the shop here in a few.

Monroe
  Team Prometheus
Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 15, 2016, 01:03:03 pm
16MHz clock uses the same fuses, just different hex.
What is different in the hex for 16Mhz ?
You mean a "config.h" parameter somewhere ?

Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 15, 2016, 01:18:51 pm
yes, it's a flag in the makefile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 15, 2016, 02:17:42 pm
OK! Life

Now to find a 36pf cap to calibrate. I ran the 3 lines separate in order as suggested and that worked.

Thanks a bunch guys!

Monroe

Oh! What's the reasoning for going to 16 mhz? I happen to have some on hand.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 15, 2016, 02:43:37 pm
OK! Life

Now to find a 36pf cap to calibrate. I ran the 3 lines separate in order as suggested and that worked.

Thanks a bunch guys!

Monroe

Oh! What's the reasoning for going to 16 mhz? I happen to have some on hand.

Awesome!

From what I read, 16Mhz will give you better resolution and accuracy when measuring capacity and inductance.  You will also notice the device more peppier.

Btw, what fuses did you set?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 15, 2016, 02:58:14 pm
Thought i'd open my MK-328 and put some pictures up.

Thanks.

Quote
Differences with mine are, Green PCB but seems decent quality, no EZM Studios logo on the casing or inside, but exactly the same PCB layout and components.
Looks like a clone of a clone.  Regardless, I still find this unit the best looking and well thought out.  :P
Its easy to replace the ZIF board.  Build quality seem top notch and its design to be able to take some beating :box: 

Quote
About to fit a 16mhz Crystal and debating fitting a rotary encoder...
Upgrading the xtal is nice and easy.  As for the encoder, I think its useful if you plan spend a lot  of time in Freq/PWM Gen menus, for everything else a switch does a superb job. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 15, 2016, 03:19:53 pm
Fuses

avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m

They could have included a 36puff in the kit :(

Monroe
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 15, 2016, 03:27:43 pm
the kit comes with older firmware :)

you dont need the small cap, just let the test timeout.
it's only for reading small inductors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 15, 2016, 03:38:09 pm
Fuses

avrdude -c USBasp -p m328p -U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m

They could have included a 36puff in the kit :(

Monroe

Interesting, I thought 5 top most bits of efuse weren't used on m328p.

I get an error on mine.
Code: [Select]
avrdude: reading input file "0xfc"
avrdude: writing efuse (1 bytes):

Writing |                                                    | 0% 0.00s ***failed;
Writing | ################################################## | 100% 0.07s

avrdude: 1 bytes of efuse written
avrdude: verifying efuse memory against 0xfc:
avrdude: load data efuse data from input file 0xfc:
avrdude: input file 0xfc contains 1 bytes
avrdude: reading on-chip efuse data:

Reading | ################################################## | 100% 0.01s

avrdude: verifying ...
avrdude: verification error, first mismatch at byte 0x0000
         0xfc != 0x04
avrdude: verification error; content mismatch

avrdude: safemode: efuse changed! Was fc, and is now 4
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 15, 2016, 04:02:18 pm
STJ I see that your a major instigator of this firmware (that's your mark on the firmware right?) if so thanks a bunch for your time and work on the project (and hanging out helping folks implement it)

Looks like a nice bit of kit!

And thanks again to vinceroger for being the first to help me out.

Is there a quick and dirty manual for this model? Not that I really need one but some of the guys that work for me ya know? lol 

An error on fuses could be a bad chip.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 15, 2016, 04:11:04 pm
It should be fairly simple to add color coding for the probe/pin numbers. Any more votes for that neat idea?

done (for the next version) :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 15, 2016, 05:13:08 pm
@madires,

I have the AY-AT with upgraded 16Mhz xtal.  Recompiled "m" with FREQ = 16.  I've noticed something bizarre.  Testing 334k cap I get matching 330nF/0.45 \$\Omega\$ readings just as "k" reports.  However, with 224k cap, "m" says 215nF/2.27 \$\Omega\$ but "k" says 215nF/0.98 \$\Omega\$.  An error of magnitude of 2.  If I remember correctly, with 8Mhz xtal the readings of 224k cap matched "k".

p.s. Colors  :-+ Can't wait for next version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 15, 2016, 06:31:45 pm
I have the AY-AT with upgraded 16Mhz xtal.  Recompiled "m" with FREQ = 16.  I've noticed something bizarre.  Testing 334k cap I get matching 330nF/0.45 \$\Omega\$ readings just as "k" reports.  However, with 224k cap, "m" says 215nF/2.27 \$\Omega\$ but "k" says 215nF/0.98 \$\Omega\$.  An error of magnitude of 2.  If I remember correctly, with 8Mhz xtal the readings of 224k cap matched "k".

That's strange. If it would be some timing issue, all ESR measurements should be off by a factor of two. I'll look into it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 15, 2016, 07:04:03 pm
Thought i'd open my MK-328 and put some pictures up.

Thanks.

Quote
Differences with mine are, Green PCB but seems decent quality, no EZM Studios logo on the casing or inside, but exactly the same PCB layout and components.
Looks like a clone of a clone.  Regardless, I still find this unit the best looking and well thought out.  :P
Its easy to replace the ZIF board.  Build quality seem top notch and its design to be able to take some beating :box: 

Quote
About to fit a 16mhz Crystal and debating fitting a rotary encoder...
Upgrading the xtal is nice and easy.  As for the encoder, I think its useful if you plan spend a lot  of time in Freq/PWM Gen menus, for everything else a switch does a superb job.


Yeah I'd say it's a clone, but they are all pretty much clones of something so not bothered, PCB is an exact copy, same case, sticker fonts are identical and markings comparing it with another,
so who knows they might all even come out of the same place. Cost me £17 delivered with the ZIF, a lot of listings didn't have a ZIF included which I wanted.

I'll put a the 16mhz in when I get chance, loaded up the makefile today to have a play, will flash it when I fit the crystal.

Nah won't be using the frequency stuff on it, I can manage with the press and hold for the button, just always a case of upgraditis and tinkering, if I had an encoder here I'd put it in but not buying one just for that.

Not sure whether to go K or M firmware though, did see a post on here a while back with differences but I can't find it now  |O Screenshots of both firmwares I have been looking for too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 15, 2016, 08:01:29 pm
I've attached the README included with "m" firmware, created by Markus Reschke aka madires on here.  You can get a taste of what his firmware is like.

Title: Re: $20 LCR ESR Transistor checker project
Post by: roli_bark on September 16, 2016, 06:13:35 am
I've attached the README included with "m" firmware, created by Markus Reschke aka madires on here.  You can get a taste of what his firmware is like.
I see some discussions here mentioning the Atmega644/1284 as options. But I looked for & could find NO kits for it.

And BTW [flywheels] there're minor 2 typos in your 'readme.txt' - 664 should be 644...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 16, 2016, 10:02:20 am
I see some discussions here mentioning the Atmega644/1284 as options. But I looked for & could find NO kits for it.

And BTW [flywheels] there're minor 2 typos in your 'readme.txt' - 664 should be 644...

My bad ;) There aren't any ATmega644/1284 kits yet, just the circuit in Karl-Heinz' documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 16, 2016, 03:40:44 pm
I hope someone can prove me wrong, but I don't think we can expect any kits based on the ATmega644 series any time soon. It's a shame, but 324 is as good as it will ever get. :( That's because the Chinese cloners are trying to use the minimal part count (how many kits have a zener test circuit built in?). Not many of them will want to add four additional chips and two transistors that are hard if not impossible to find good equivalents of just for the sake of measuring crystals and frequencies, and they won't bother trying to understand which parts of the circuit can be safely removed. Not to mention that the processor itself is more expensive. It would have been better to publish a more bare-bones version of the circuit. That would've looked more attractive to them. Then the rest could have been shown as an add-on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 16, 2016, 03:43:27 pm
I hope someone can prove me wrong, but I don't think we can expect any kits based on the ATmega644 series any time soon. It's a shame, but 324 is as good as it will ever get. :( That's because the Chinese cloners are trying to use the minimal part count (how many kits have a zener test circuit built in?). Not many of them will want to add four additional chips and two transistors that are hard if not impossible to find good equivalents of just for the sake of measuring crystals and frequencies, and they won't bother trying to understand which parts of the circuit can be safely removed. Not to mention that the processor itself is more expensive. It would have been better to publish a more bare-bones version of the circuit. That would've looked more attractive to them. Then the rest could have been shown as an add-on.

I'm still waiting for a "kit" or "bare" 324 one to come up.

If the source is there for the 644 it won't be difficult to knock one up ourselves to be honest.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 16, 2016, 03:51:37 pm
The schematic is shown in the manual. I'm not a fan of all the jumpers, this being an MCU-based circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 16, 2016, 04:03:05 pm
jumpers?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 16, 2016, 04:14:48 pm
Have a look at the attached image.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 16, 2016, 05:34:50 pm
i wouldnt even bother with the frequency counter circuit.

i have an 8digit 2.5GHz counter from china that cost the same as the component tester!
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 16, 2016, 05:41:01 pm
i wouldnt even bother with the frequency counter circuit.
[...]

Ditto. I'm just saying that the way the circuit is presented at the moment, no Chinese cloner will want to try to implement it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on September 17, 2016, 03:46:30 am
i wouldnt even bother with the frequency counter circuit.
[...]

Ditto. I'm just saying that the way the circuit is presented at the moment, no Chinese cloner will want to try to implement it.

It is the business decision for them to make as they are taking the full risk on the volume run, inventory and betting that the sale will be there for some profit on this low price device to the hobbyists.  Anyone can go there and bet their money to chunk out a  version they think that can sell better.  For me, I am thankful that someone had taken the trouble and the risks to make this tester at a price that I can afford to buy a few.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 17, 2016, 07:07:32 am
Has anyone compared the transistor tester's accuracy regarding ESR measurements against the popular DER-EE DE-5000?

I mainly got the tester for testing ESR and vloss of capacitors but I'm thinking I should also buy the de-5000 for more accurate measurements.
I can't dispute the testers' readings since I only have that and nothing to compare it to.

If someone did a comparison and proved these instruments are close I could make do with just the tester for now since most capacitors I end up checking are suspicious anyways and therefore get replaced regardless of the readings.
But I'd love to see/read a comparison.

There was a youtube video I stumbled upon comparing four capacitor test devices including the tester and de-5000 but I believe the comparison was somewhat invalid since the tester was measuring at 100Hz and the DE-5000 at 120Hz.(if I remember correctly)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 17, 2016, 09:43:42 am
there was a comparison done with some other testers, it may have been on the other forum if it's not in this thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 17, 2016, 06:52:42 pm
Here is one post with comparing k to m to Agilent U1733C (@10kHz).
Link (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg860317/#msg860317)
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on September 17, 2016, 11:19:45 pm
I think I'll get a de-5000 anyways because it can do other stuff as well but I wanted to see if anyone bothered to compare it with a "proper" instrument.

From the post above it seems to perform well enough for straight capacitance.

I already tested some good (new) and bad caps and measurements seemed to be in the ballpark I guess, although I don't have anything other than a DMM and datasheets (for the new caps) to compare it to..

Overall I'm quite happy with this little gadget;for its price it's certainly a must have for anyone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 18, 2016, 12:47:32 am
I think I'll get a de-5000 anyways because it can do other stuff as well but I wanted to see if anyone bothered to compare it with a "proper" instrument.

From the post above it seems to perform well enough for straight capacitance.

I already tested some good (new) and bad caps and measurements seemed to be in the ballpark I guess, although I don't have anything other than a DMM and datasheets (for the new caps) to compare it to..

Overall I'm quite happy with this little gadget;for its price it's certainly a must have for anyone.

Not sure if you've seen this video about the DE-5000 and what it can do. <Link> (https://youtu.be/ivVSq0IiZGo)  WARNING: The information contained in this video could cause a person to go  :scared:

If you do decide to do a comparison, I would love to see it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 18, 2016, 02:23:19 am
[...]
WARNING: The information contained in this video could cause a person to go  :scared:
[...]

Especially when someone concedes that we're not living in the real world (at about 53:29)!  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kosti on September 18, 2016, 12:38:23 pm
Apology for the noob 1st post but I am a little confused on which fleabay item to purchased and which FW is to be used  :-//

I am looking for mainly an "in circuit ESR meter" to check caps on a GPU graphics card so am wondering what is the best method or unit to build or buy since there are a number of ESR options

[1]Grab this one from ebay http://www.ebay.com.au/itm/172230778097?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com.au/itm/172230778097?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
[2]Build one that I like from Jay_Diddy_B as there are 2 that I like but in particular the DMM
https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/ (https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/)
or
https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/150/ (https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/150/)
I believe there may have been a possibility for a kit from Jay but not seen any update for a while
[3]Grab this one from banggood http://www.banggood.com/it/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/it/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)
[4]Get this one http://www.ebay.com.au/itm/221923378500?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com.au/itm/221923378500?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT) but do not think this is capable of in circuit testing

Ideally if this project thread there is some great support so I am keen on an AIO unit, but again I am just not sure which what I should go and didnt want to bump older threads hence my query now in this thread

Any guidance is appreciated

PEACE
Kosti
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 18, 2016, 12:47:51 pm
Apology for the noob 1st post but I am a little confused on which fleabay item to purchased and which FW is to be used  :-//

I am looking for mainly an "in circuit ESR meter" to check caps on a GPU graphics card so am wondering what is the best method or unit to build or buy since there are a number of ESR options

firstly, you cant do in-circuit testing.
that's a myth from the days of CRT tv's when caps where not used in parallel with each other.

as for the best tester, i would say it's the TFT colour kit at the moment - unless you want one that's built.
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on September 18, 2016, 01:22:50 pm
Not that I know , but thought [ without trying ] that depending on in circuit , series / parallel , math is used , same as like batteries in series add voltage , in parallel add current ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 18, 2016, 01:53:29 pm
no.

lets say you have 3 caps in parallel.
if you multiply the esr by 3, you are assuming they are all the same.
when one may be bad.
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on September 18, 2016, 02:45:46 pm
Well again just basic math , if the math and the value marked on caps do not match , then looking at caps individually ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: retrolefty on September 18, 2016, 08:36:00 pm
no.

lets say you have 3 caps in parallel.
if you multiply the esr by 3, you are assuming they are all the same.
when one may be bad.

 You mean divide by 3, they are in parallel.

Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 18, 2016, 09:15:43 pm
no.

lets say you have 3 caps in parallel.
if you multiply the esr by 3, you are assuming they are all the same.
when one may be bad.

 You mean divide by 3, they are in parallel.

no, i mean lift them and test them individually.  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 18, 2016, 09:38:18 pm
I am looking for mainly an "in circuit ESR meter" to check caps on a GPU graphics card so am wondering what is the best method or unit to build or buy since there are a number of ESR options

Although in-circuit testing can be done, depending on the circuit layout, doing so may only be a hint that something may be incorrect, which will have to be followed up with out-of-circuit testing of individual components. However, in-circuit testing could just as well yield completely erroneous or misleading results, requiring out-of-circuit testing.

Regardless of the equipment, you need to know the circuit layout and the implications of how and what you're testing. For best results (and fewer headaches), test components out of circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on September 18, 2016, 09:48:37 pm
no.

lets say you have 3 caps in parallel.
if you multiply the esr by 3, you are assuming they are all the same.
when one may be bad.

 You mean divide by 3, they are in parallel.

no, i mean lift them and test them individually.  ;D
No, he really meant MULTIPLY the ESR by 3.  If you want to know the capacitance of each capacitor, assuming they are all identical then you would divide the total capacitance by 3.

If you have 3 identical capacitor in parallel with identical ESR, the ESR of one capacitor would be 3 times the parallel ESR (again assuming all 3 ESR are identical).  If you have 3 capacitors in parallel and one of them is bad (its ESR is high) then you cannot tell from the parallel ESR that you have a bad capacitor.  That is why you need to test each capacitor individually, out of circuit!
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 18, 2016, 10:26:43 pm
in reality it's more common to find an electrolytic with a ceramic in parallel with it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on September 18, 2016, 10:59:59 pm
If it is only one electrolytic in parallel with a ceramic (assuming the ceramic is not bad) then the measured ESR would be mostly the ESR of the electrolytic since the ESR of the ceramic would be at least an order of magnitude higher than a good electrolytic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 19, 2016, 12:40:27 am
in reality it's more common to find an electrolytic with a ceramic in parallel with it.

Linear power supplies, audio amplifiers etc have electrolytics in parallel.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monroe on September 19, 2016, 02:07:04 am
So far I really like this little tester and it was worth the effort.

I have a question OT: I have a LeCroy 9400A that I would like to upgrade to the FFT option however I do not have and do not want to buy a eprom burner for a 7256 eprom. I have 6 eproms that need to be burned if someone has a burner and would be willing to help me out?

Monroe
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kosti on September 19, 2016, 05:11:43 am
Hi All

Thanks for the reply people

Apology again can someone please point / link to me which unit [TFT colour kit] that was mentioned? I',m happy to build it and add this to my arsenal of tools to figure out this GPU issue however its impossible to obtain the schematic, but I suspect something is causing the GPU not to post to display, I could try the "other" myth of baking it but for now happy to try my hand in trying to check a few caps /trans etc see if this leads me to the defect. If it ends up being the GPU MPU itself so being it.

I was going to try and build the CRO method of adding in a 100khz signal but my freq gen is somewhere in storage and hasn't been used in like 20 years! I'm trying to get back into some basic fault finding and hope I can have a crack and resurrecting this paper weight

A link to the latest Kit and FW I should grab from ebay or another source would be appreciated chaps, :-+
PEACE
Kosti
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on September 19, 2016, 07:34:27 am
For example, the here so called 'AY-AT' color kit:
http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.56.J7yA7x (http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.56.J7yA7x)

AY-AT - K firmware: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=249731

AY-AT - M firmware: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=252428

Instructions attachments
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on September 19, 2016, 09:10:32 am
For example, the here so called 'AY-AT' color kit:
http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.56.J7yA7x (http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.56.J7yA7x)

AY-AT - K firmware: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=249731

AY-AT - M firmware: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=252428

Instructions attachments

Hi Willem52

What are the fuse settings for the M firmware?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kosti on September 19, 2016, 09:37:00 am
For example, the here so called 'AY-AT' color kit:
http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.56.J7yA7x (http://www.aliexpress.com/item/2016-DIY-kits-TFT-LCD-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square/32649811953.html?spm=2114.13010608.0.56.J7yA7x)

AY-AT - K firmware: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=249731

AY-AT - M firmware: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=252428

Instructions attachments

Thanks for taking the time to link these, I will look at grabbing one of them

Is this one the same of different since I don't use Aliexpress I found this one on ebay

http://www.ebay.com.au/itm/GM328A-LCD-Transistor-Tester-Diode-LCR-ESR-Meter-PWM-Square-Wave-Generator-M3M3-/311674321737?hash=item48913cbb49:g:sjgAAOSwCGVX3NDJ (http://www.ebay.com.au/itm/GM328A-LCD-Transistor-Tester-Diode-LCR-ESR-Meter-PWM-Square-Wave-Generator-M3M3-/311674321737?hash=item48913cbb49:g:sjgAAOSwCGVX3NDJ)

As for protection do you need to add in some diodes in the event some caps may still have charge?

PEACE
Kosti
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 19, 2016, 10:33:34 am
What are the fuse settings for the M firmware?

The same like for the k-firmware: -U hfuse:w:0xd9:m -U efuse:w:0xfc:m -U lfuse:w:0xf7:m
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on September 19, 2016, 12:49:14 pm
Is this one the same of different since I don't use Aliexpress I found this one on ebay

http://www.ebay.com.au/itm/GM328A-LCD-Transistor-Tester-Diode-LCR-ESR-Meter-PWM-Square-Wave-Generator-M3M3-/311674321737?hash=item48913cbb49:g:sjgAAOSwCGVX3NDJ (http://www.ebay.com.au/itm/GM328A-LCD-Transistor-Tester-Diode-LCR-ESR-Meter-PWM-Square-Wave-Generator-M3M3-/311674321737?hash=item48913cbb49:g:sjgAAOSwCGVX3NDJ)

As for protection do you need to add in some diodes in the event some caps may still have charge?

PEACE
Kosti

I think these are a clone of a clone. In this case a ready built one with SMD components.
This one has also the protection components like the 'AY-AT' does.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 19, 2016, 12:53:03 pm
it's also mislabeled "GM328A"
that guy needs his ass kicked hard, someone is going to re-flash it with the wrong firmware because of that - i just know it!

btw, DONT BUY IT.
look at the 10k resistor to the left of the encoder!!!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 19, 2016, 12:59:07 pm
this is the original.
http://www.ebay.com.au/itm/182221397168 (http://www.ebay.com.au/itm/182221397168)

and a case!
http://www.ebay.com.au/itm/112108340467 (http://www.ebay.com.au/itm/112108340467)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 19, 2016, 03:07:02 pm
it's also mislabeled "GM328A"
that guy needs his ass kicked hard, someone is going to re-flash it with the wrong firmware because of that - i just know it!

btw, DONT BUY IT.
look at the 10k resistor to the left of the encoder!!!!

That 10k resistor is priceless!  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: NiklasO on September 19, 2016, 05:36:41 pm
Thought i'd open my MK-328 and put some pictures up.

Differences with mine are, Green PCB but seems decent quality, no EZM Studios logo on the casing or inside, but exactly the same PCB layout and components.
Ignore the hot snot on the terminals, I put that there.

About to fit a 16mhz Crystal and debating fitting a rotary encoder...


I got the same one. You don't happen to have the latest m-firmware compiled (or the Makefile for m?) for this one or could someone compile it for me (8Mhz)? Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 19, 2016, 08:57:49 pm
Thought i'd open my MK-328 and put some pictures up.

Differences with mine are, Green PCB but seems decent quality, no EZM Studios logo on the casing or inside, but exactly the same PCB layout and components.
Ignore the hot snot on the terminals, I put that there.

About to fit a 16mhz Crystal and debating fitting a rotary encoder...


I got the same one. You don't happen to have the latest m-firmware compiled (or the Makefile for m?) for this one or could someone compile it for me (8Mhz)? Thanks!

I still haven't flashed mine as I'm trying to find the original firmware just in case I want to go back to it, either MK-328 or GM328 Firmware.

Does yours also not say EZM Electronic Studio? I think these may just be later versions as I looked at all the pictures of the ones sold on Banggood and none say EZM Electronic Studio on the customer review images.

Also the red boards were dated 2014.
Title: Re: $20 LCR ESR Transistor checker project
Post by: NiklasO on September 19, 2016, 09:13:15 pm
Thought i'd open my MK-328 and put some pictures up.

Differences with mine are, Green PCB but seems decent quality, no EZM Studios logo on the casing or inside, but exactly the same PCB layout and components.
Ignore the hot snot on the terminals, I put that there.

About to fit a 16mhz Crystal and debating fitting a rotary encoder...


I got the same one. You don't happen to have the latest m-firmware compiled (or the Makefile for m?) for this one or could someone compile it for me (8Mhz)? Thanks!

I still haven't flashed mine as I'm trying to find the original firmware just in case I want to go back to it, either MK-328 or GM328 Firmware.

Does yours also not say EZM Electronic Studio? I think these may just be later versions as I looked at all the pictures of the ones sold on Banggood and none say EZM Electronic Studio on the customer review images.

Also the red boards were dated 2014.

I have no EZM on board or case. Mine looks exactly like yours.

Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 19, 2016, 09:32:21 pm

I still haven't flashed mine as I'm trying to find the original firmware just in case I want to go back to it, either MK-328 or GM328 Firmware.


The Chinese are not relenting to give up the original firmware and they usually lock the chips  :--.  Have you tried contacting the seller, maybe offer exchange for a positive feedback?  In any case take pics of the "Menu" to see what they enabled so you can recreate later. 

The most refined and reliable firmware is the "k".   The automatic Capacitor test on pins 1 and 3 as great when you got a batch of caps to test.   I think most testers are based on "k".  On the other hand, the "m" is speedy, flashy, with extra features but might need some tweaking.

Above statement is my opinion.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hansibull on September 19, 2016, 10:34:55 pm
Does anybody know of it's possible to download the "Chinese" firmware somewhere?
I messed up big time with my transistor tester (The one with a case and color TFT (http://www.ebay.com/itm/182170556129)), and connected it to a circuit with charged capacitor. The result is a dead analog pin.

I tried dumping the firmware from the ATmega324PA using avrdude, but it kept telling me that the dumped binary file was empty, so they must have set the lock bits. I tried using Markus' firmware, but I'm struggling  to get it working properly. The original FW also looked a lot nicer on a color LCD.

I was thinking about ordering a new chip, replace the current one and reflash it with the original FW (hopefully). Is this a dead end?

The original firmware was "M-Tester v2.12k".
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 20, 2016, 12:22:57 am
Does anybody know of it's possible to download the "Chinese" firmware somewhere?
...
I tried using Markus' firmware, but I'm struggling  to get it working properly. The original FW also looked a lot nicer on a color LCD.

The "Chinese" firmware are closed ripoffs of the open-source original and open-source variations of the original. Those losers :box: lock the chip when they program them and don't contribute modifications (such as fancier color display output) back to the community from which they're benefiting. :rant: :wtf:

If you're having trouble getting it working with the "m" firmware, perhaps try the "k" firmware (the original, original) to see if that gets you up and running. Markus and others here with intimate understanding of the firmware are an invaluable resource, unlike the manufacturers and vendors who mass produce and distribute these devices.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 20, 2016, 12:33:53 am
Does anybody know of it's possible to download the "Chinese" firmware somewhere?
I messed up big time with my transistor tester (The one with a case and color TFT (http://www.ebay.com/itm/182170556129)), and connected it to a circuit with charged capacitor. The result is a dead analog pin.

I tried dumping the firmware from the ATmega324PA using avrdude, but it kept telling me that the dumped binary file was empty, so they must have set the lock bits. I tried using Markus' firmware, but I'm struggling  to get it working properly. The original FW also looked a lot nicer on a color LCD.

I was thinking about ordering a new chip, replace the current one and reflash it with the original FW (hopefully). Is this a dead end?

The original firmware was "M-Tester v2.12k".

I doubt you will ever get your hands on that firmware  :(.  It's the most heavily modified most beatiful UI of its kind.  You might need to settle with open source.  Maybe there is an unused pin you could use in place of the dead pin and modify the source code?

What kind of struggles are you having with getting open source to work?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dwaine on September 20, 2016, 03:06:34 am
Does anybody know of it's possible to download the "Chinese" firmware somewhere?
I messed up big time with my transistor tester (The one with a case and color TFT (http://www.ebay.com/itm/182170556129)), and connected it to a circuit with charged capacitor. The result is a dead analog pin.

I tried dumping the firmware from the ATmega324PA using avrdude, but it kept telling me that the dumped binary file was empty, so they must have set the lock bits. I tried using Markus' firmware, but I'm struggling  to get it working properly. The original FW also looked a lot nicer on a color LCD.

I was thinking about ordering a new chip, replace the current one and reflash it with the original FW (hopefully). Is this a dead end?

The original firmware was "M-Tester v2.12k".

I have the same unit and did the same thing.    My unit will not power up now, but it still will charge the battery.  I really like the unit and it was 16mhz clock.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hansibull on September 20, 2016, 06:01:33 am
Mine "boots" up, but the text is a little off screen (a few pixels in each axis), and it shuts off within 4 seconds, no matter what I configure it to be. If I power it with my USBtinyISP programmer, it stays on a little longer, enough to show what part it is for about a tenth of a second before the display just says "Bye". It stays like this until I remove the programmer, which is fair. Modifying CYCLE_DELAY and CYCLE_MAX does not change anything. I guess I'll have to desolder the LCD and reverse engineer the whole board to make sure all the wiring correspond to the firmware.

The QR code on the PCB links to http://91make.world.taobao.com (http://91make.world.taobao.com), but I've not been able to contact the seller (Chinese is not my strongest side).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on September 20, 2016, 09:01:37 am
Does anybody know of it's possible to download the "Chinese" firmware somewhere?
I messed up big time with my transistor tester (The one with a case and color TFT (http://www.ebay.com/itm/182170556129)), and connected it to a circuit with charged capacitor. The result is a dead analog pin.

I tried dumping the firmware from the ATmega324PA using avrdude, but it kept telling me that the dumped binary file was empty, so they must have set the lock bits. I tried using Markus' firmware, but I'm struggling  to get it working properly. The original FW also looked a lot nicer on a color LCD.

I was thinking about ordering a new chip, replace the current one and reflash it with the original FW (hopefully). Is this a dead end?

The original firmware was "M-Tester v2.12k".

I doubt you will ever get your hands on that firmware  :(.  It's the most heavily modified most beatiful UI of its kind.  You might need to settle with open source.  Maybe there is an unused pin you could use in place of the dead pin and modify the source code?

What kind of struggles are you having with getting open source to work?

I've posted the original firmware for the Color kit in this post.
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg969074/#msg969074
Post 2130.
Meaybe it wil help you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hansibull on September 20, 2016, 09:41:34 am
Does anybody know of it's possible to download the "Chinese" firmware somewhere?
I messed up big time with my transistor tester (The one with a case and color TFT (http://www.ebay.com/itm/182170556129)), and connected it to a circuit with charged capacitor. The result is a dead analog pin.

I tried dumping the firmware from the ATmega324PA using avrdude, but it kept telling me that the dumped binary file was empty, so they must have set the lock bits. I tried using Markus' firmware, but I'm struggling  to get it working properly. The original FW also looked a lot nicer on a color LCD.

I was thinking about ordering a new chip, replace the current one and reflash it with the original FW (hopefully). Is this a dead end?

The original firmware was "M-Tester v2.12k".

I doubt you will ever get your hands on that firmware  :(.  It's the most heavily modified most beatiful UI of its kind.  You might need to settle with open source.  Maybe there is an unused pin you could use in place of the dead pin and modify the source code?

What kind of struggles are you having with getting open source to work?

I've posted the original firmware for the Color kit in this post.
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg969074/#msg969074
Post 2130.
Meaybe it wil help you.

Does this got the same UI as the The transistor tester I have? Is it compiled for the ATmega328 or ATmega324?
(http://47.88.17.41/images/DF09BB9864594CBF969B9DD01A30186D.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 20, 2016, 11:30:29 am

I still haven't flashed mine as I'm trying to find the original firmware just in case I want to go back to it, either MK-328 or GM328 Firmware.


The Chinese are not relenting to give up the original firmware and they usually lock the chips  :--.  Have you tried contacting the seller, maybe offer exchange for a positive feedback?  In any case take pics of the "Menu" to see what they enabled so you can recreate later. 

The most refined and reliable firmware is the "k".   The automatic Capacitor test on pins 1 and 3 as great when you got a batch of caps to test.   I think most testers are based on "k".  On the other hand, the "m" is speedy, flashy, with extra features but might need some tweaking.

Above statement is my opinion.

Mine is based on 1.12k firmware, but I do like the Font, Layout of symbols and readability, I think it's been tweaked slightly.
I'd love to see some screen shots of M firmware but cannot find any anywhere.

I took some pictures of mine, testing a few items and also the "Hidden Menu"

http://imgur.com/a/xWu9n (http://imgur.com/a/xWu9n)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 20, 2016, 11:32:31 am
Does anybody know of it's possible to download the "Chinese" firmware somewhere?
I messed up big time with my transistor tester (The one with a case and color TFT (http://www.ebay.com/itm/182170556129)), and connected it to a circuit with charged capacitor. The result is a dead analog pin.

I tried dumping the firmware from the ATmega324PA using avrdude, but it kept telling me that the dumped binary file was empty, so they must have set the lock bits. I tried using Markus' firmware, but I'm struggling  to get it working properly. The original FW also looked a lot nicer on a color LCD.

I was thinking about ordering a new chip, replace the current one and reflash it with the original FW (hopefully). Is this a dead end?

The original firmware was "M-Tester v2.12k".

I doubt you will ever get your hands on that firmware  :(.  It's the most heavily modified most beatiful UI of its kind.  You might need to settle with open source.  Maybe there is an unused pin you could use in place of the dead pin and modify the source code?

What kind of struggles are you having with getting open source to work?

I've posted the original firmware for the Color kit in this post.
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg969074/#msg969074
Post 2130.
Meaybe it wil help you.

Does this got the same UI as the The transistor tester I have? Is it compiled for the ATmega328 or ATmega324?
(http://47.88.17.41/images/DF09BB9864594CBF969B9DD01A30186D.jpg)

All the devices I have seen with that UI seem to be based on the ATmega324.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2016, 11:40:21 am
I tried dumping the firmware from the ATmega324PA using avrdude, but it kept telling me that the dumped binary file was empty, so they must have set the lock bits. I tried using Markus' firmware, but I'm struggling  to get it working properly. The original FW also looked a lot nicer on a color LCD.

The m-firmware doesn't fully support the ATmega324/644/1284 yet, but I'm working on it. There are several changes in the code already, still a lot has to be adapted to allow the necessary port/pin variations. Also I want to use the additional possibilities by the 324/644/1284, like hardware SPI for displays. I've just finished a 324/644/1284 dev board and etched the first PCB (fresh out of the etching tank). A lot of work, a lot of fun ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: NiklasO on September 20, 2016, 11:40:54 am

I still haven't flashed mine as I'm trying to find the original firmware just in case I want to go back to it, either MK-328 or GM328 Firmware.


The Chinese are not relenting to give up the original firmware and they usually lock the chips  :--.  Have you tried contacting the seller, maybe offer exchange for a positive feedback?  In any case take pics of the "Menu" to see what they enabled so you can recreate later. 

The most refined and reliable firmware is the "k".   The automatic Capacitor test on pins 1 and 3 as great when you got a batch of caps to test.   I think most testers are based on "k".  On the other hand, the "m" is speedy, flashy, with extra features but might need some tweaking.

Above statement is my opinion.

Mine is based on 1.12k firmware, but I do like the Font, Layout of symbols and readability, I think it's been tweaked slightly.
I'd love to see some screen shots of M firmware but cannot find any anywhere.

I took some pictures of mine, testing a few items and also the "Hidden Menu"

http://imgur.com/a/xWu9n (http://imgur.com/a/xWu9n)

I used this one (trendy 1.22m) and it seems to work.
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg964239/?topicseen#msg964239

I can't compile with the config.h and Makefile from that one because the layout for the files has changed between 1.22 -> 1.24.
I can only power my device using the usbasp at 5V (need to buy some 9v batteries, hehe) and I only have 3.3, 5 or 12 volt power at home for the moment.
The text is good with the 1.22m but I can't post pictures using it because the unit does not like 4.5V - 5V from the usbasp. Getting some text and then "Bye!" because of low battery. ;) I know it is possible to make it accept 5V or lower if tweaking the Makefile or config.h but I don't know how really and as I said, cant use the config.h or Makefile for 1.24m.

Could someone please "port" the linked files to compile on 1.24m for my tester? I have found different Makefiles but I can't say I know what I am doing. One Makefile made it work but the text on screen was inverted and in the wrong position (at the bottom) and then I gave up.

Edit: I also have the LCD TFT-color unit you talk about above and I'm NOT messing with it. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2016, 11:58:33 am
The text is good with the 1.22m but I can't post pictures using it because the unit does not like 4.5V - 5V from the usbasp. Getting some text and then "Bye!" because of low battery. ;) I know it is possible to make it accept 5V or lower if tweaking the Makefile or config.h but I don't know how really and as I said, cant use the config.h or Makefile for 1.24m.

Could someone please "port" the linked files to compile on 1.24m for my tester? I have found different Makefiles but I can't say I know what I am doing. One Makefile made it work but the text on screen was inverted and in the wrong position (at the bottom) and then I gave up.

In the Makefile it's just the MCU type, clock and the programmer. Simply copy the values from your working one. The old config.h was split into a new config.h (MCU independant settings) and a config_328.h (MCU specific settings) with some minor changes. Take the old config.h and look for the settings in the new config.h/config_328.h and copy/change them. The battery low level can be set by BAT_POOR in config.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: NiklasO on September 20, 2016, 12:23:03 pm
The text is good with the 1.22m but I can't post pictures using it because the unit does not like 4.5V - 5V from the usbasp. Getting some text and then "Bye!" because of low battery. ;) I know it is possible to make it accept 5V or lower if tweaking the Makefile or config.h but I don't know how really and as I said, cant use the config.h or Makefile for 1.24m.

Could someone please "port" the linked files to compile on 1.24m for my tester? I have found different Makefiles but I can't say I know what I am doing. One Makefile made it work but the text on screen was inverted and in the wrong position (at the bottom) and then I gave up.

In the Makefile it's just the MCU type, clock and the programmer. Simply copy the values from your working one. The old config.h was split into a new config.h (MCU independant settings) and a config_328.h (MCU specific settings) with some minor changes. Take the old config.h and look for the settings in the new config.h/config_328.h and copy/change them. The battery low level can be set by BAT_POOR in config.h.

Thanks. Seems to be working now. Tried it last night but I think I was too tired. ;)

Looks about right? I have since picture taken removed IR detection

Edit: detects cap at 20pF when nothing connected (adjusted/selftest). I know I read something about that in this thread but can't find it again..
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 20, 2016, 01:01:02 pm
The text is good with the 1.22m but I can't post pictures using it because the unit does not like 4.5V - 5V from the usbasp. Getting some text and then "Bye!" because of low battery. ;) I know it is possible to make it accept 5V or lower if tweaking the Makefile or config.h but I don't know how really and as I said, cant use the config.h or Makefile for 1.24m.

Could someone please "port" the linked files to compile on 1.24m for my tester? I have found different Makefiles but I can't say I know what I am doing. One Makefile made it work but the text on screen was inverted and in the wrong position (at the bottom) and then I gave up.

In the Makefile it's just the MCU type, clock and the programmer. Simply copy the values from your working one. The old config.h was split into a new config.h (MCU independant settings) and a config_328.h (MCU specific settings) with some minor changes. Take the old config.h and look for the settings in the new config.h/config_328.h and copy/change them. The battery low level can be set by BAT_POOR in config.h.

Thanks. Seems to be working now. Tried it last night but I think I was too tired. ;)

Looks about right? I have since picture taken removed IR detection

Edit: detects cap at 20pF when nothing connected (adjusted/selftest). I know I read something about that in this thread but can't find it again..

Ah so you can remove menu items, I haven't got around to playing with the files yet. Half the stuff I don't want on there.
Can you take some more pictures of it testing items etc :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: NiklasO on September 20, 2016, 01:10:11 pm
The text is good with the 1.22m but I can't post pictures using it because the unit does not like 4.5V - 5V from the usbasp. Getting some text and then "Bye!" because of low battery. ;) I know it is possible to make it accept 5V or lower if tweaking the Makefile or config.h but I don't know how really and as I said, cant use the config.h or Makefile for 1.24m.

Could someone please "port" the linked files to compile on 1.24m for my tester? I have found different Makefiles but I can't say I know what I am doing. One Makefile made it work but the text on screen was inverted and in the wrong position (at the bottom) and then I gave up.

In the Makefile it's just the MCU type, clock and the programmer. Simply copy the values from your working one. The old config.h was split into a new config.h (MCU independant settings) and a config_328.h (MCU specific settings) with some minor changes. Take the old config.h and look for the settings in the new config.h/config_328.h and copy/change them. The battery low level can be set by BAT_POOR in config.h.

Thanks. Seems to be working now. Tried it last night but I think I was too tired. ;)

Looks about right? I have since picture taken removed IR detection

Edit: detects cap at 20pF when nothing connected (adjusted/selftest). I know I read something about that in this thread but can't find it again..

Ah so you can remove menu items, I haven't got around to playing with the files yet. Half the stuff I don't want on there.
Can you take some more pictures of it testing items etc :)

Yes. Removed some more stuff.. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 20, 2016, 01:25:45 pm
Quote! Edit: detects cap at 20pF when nothing connected (adjusted/selftest). I know I read something about that in this thread but can't find it again..

i can remember that thread too but cant find it what he did too solve it was to clean his board with ipa i think.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 20, 2016, 01:36:57 pm
Quote from: NiklasO

Yes. Removed some more stuff.. ;)

You mentioned the 20pF issue, what firmware did you compile? was it the M or K?
Title: Re: $20 LCR ESR Transistor checker project
Post by: NiklasO on September 20, 2016, 01:37:49 pm
Quote from: NiklasO

Yes. Removed some more stuff.. ;)

You mentioned the 20pF issue, what firmware did you compile? was it the M or K?

Just tried 1.24m for now. Waiting on delivery of 9V battery in like 10 minutes. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 20, 2016, 01:49:47 pm
Quote from: NiklasO

Yes. Removed some more stuff.. ;)

You mentioned the 20pF issue, what firmware did you compile? was it the M or K?

Just tried 1.24m for now. Waiting on delivery of 9V battery in like 10 minutes. ;)

Looking forward to seeing pictures of it in operation!
Title: Re: $20 LCR ESR Transistor checker project
Post by: NiklasO on September 20, 2016, 02:11:58 pm
Will take some pictures now when I have the correct battery. The 20pF reading is gone when using the right way to power the unit. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: NiklasO on September 20, 2016, 09:52:31 pm
Size comparison   ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dwaine on September 21, 2016, 05:25:02 pm
Mine "boots" up, but the text is a little off screen (a few pixels in each axis), and it shuts off within 4 seconds, no matter what I configure it to be. If I power it with my USBtinyISP programmer, it stays on a little longer, enough to show what part it is for about a tenth of a second before the display just says "Bye". It stays like this until I remove the programmer, which is fair. Modifying CYCLE_DELAY and CYCLE_MAX does not change anything. I guess I'll have to desolder the LCD and reverse engineer the whole board to make sure all the wiring correspond to the firmware.

The QR code on the PCB links to http://91make.world.taobao.com (http://91make.world.taobao.com), but I've not been able to contact the seller (Chinese is not my strongest side).

I'm just going to buy another one.  I really like the unit and it was pretty accurate.   They were not kidding when they say, "Discharge Capacitors".  I just plugged in a capacitor after just testing it.  It still had a charge in it.

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Back2Volts on September 22, 2016, 01:37:39 pm

I'm just going to buy another one.  I really like the unit and it was pretty accurate.   They were not kidding when they say, "Discharge Capacitors".  I just plugged in a capacitor after just testing it.  It still had a charge in it.

I am surprised nobody has thought of putting a strip of tinned PCB above the jacks, under the discharge warning.   
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 22, 2016, 01:47:23 pm
I am surprised nobody has thought of putting a strip of tinned PCB above the jacks, under the discharge warning.   

Please see below the pin header labeled DUT:
(http://www.radiodevices.ru/ct/ct10-b2.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on September 22, 2016, 02:14:14 pm
Dang I like that layout for SMD's ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 22, 2016, 05:49:43 pm

I'm just going to buy another one.  I really like the unit and it was pretty accurate.   They were not kidding when they say, "Discharge Capacitors".  I just plugged in a capacitor after just testing it.  It still had a charge in it.

I am surprised nobody has thought of putting a strip of tinned PCB above the jacks, under the discharge warning.   

Good shout that! On my MK-328 there is a slot cut out for something, I'll put a blank PCB behind there and cut the label through.

(http://i1086.photobucket.com/albums/j457/thebayuk/EEVblog/20160915_090557_zpsivticxkj.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 22, 2016, 07:11:27 pm
I am surprised nobody has thought of putting a strip of tinned PCB above the jacks, under the discharge warning.   

Good shout that! On my MK-328 there is a slot cut out for something, I'll put a blank PCB behind there and cut the label through.

(http://i1086.photobucket.com/albums/j457/thebayuk/EEVblog/20160915_090557_zpsivticxkj.jpg)

Good idea. That case has lots of space for stuff.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Back2Volts on September 23, 2016, 04:01:45 am
I am surprised nobody has thought of putting a strip of tinned PCB above the jacks, under the discharge warning.   

Please see below the pin header labeled DUT:
(http://www.radiodevices.ru/ct/ct10-b2.jpg)

Great device area design !
Title: Re: $20 LCR ESR Transistor checker project
Post by: almamater on September 23, 2016, 07:48:44 am
Hello, i bought this 2016 EZM328 transistor tester KIT:
(http://i.ebayimg.com/images/g/UJMAAOSwMNxXU~VP/s-l1600.jpg) (http://www.ebay.co.uk/itm/2016-EZM328-transistor-tester-ESR-frequency-meter-square-wave-genera-KITS-/172230778097?)
With V1.12K software and M328 chip.

How can we put the components at the right place? (example: match the resistors with the number\label @ the board: R1, R2, R3..etc).

Can i use the schematic "New Circuit of Transistor Tester" in the ttester.pdf (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf) manual (page 10)?


Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 23, 2016, 08:21:33 am
Hello, i bought this 2016 EZM328 transistor tester KIT:
(http://i.ebayimg.com/images/g/UJMAAOSwMNxXU~VP/s-l1600.jpg) (http://www.ebay.co.uk/itm/2016-EZM328-transistor-tester-ESR-frequency-meter-square-wave-genera-KITS-/172230778097?)
With V1.12K software and M328 chip.

How can we put the components at the right place? (example: match the resistors with the number\label @ the board: R1, R2, R3..etc).

Can i use the schematic "New Circuit of Transistor Tester" in the ttester.pdf (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf) manual (page 10)?
i have two of these testers if you read back a few pages stj helped me with the parts list and what went where etc its all in this thread including the firmware too as most of these tester have come with no firmware anything you need too know just ask

edit here you go should help you
----------------------------------------
r1 - 680r sensing circuit
r2 - 470k sensing circuit
r3 - 680r sensing circuit
r4 - 470k sensing circuit
r5 - 680r sensing circuit
r6 - 470k sensing circuit
r7 - 10k reset pullup
r8 - 33k power control
r9 - 3k3 power control
r10 - 27k
r11 - 100k (says r1 but is next to r10)
r12 - 10k voltage divider for battery sense
r13 - 3k3 voltage divider for battery sense
r14 - 560r display related - led current limit
r15 - 27k
r16 - 0r jumper for AVCC
r17 - 2k2 from tl431 to vcc
r18 - 1k rotary encoder current limit
r19 - 1k rotary encoder current limit
r20 - 10k rotary encoder pullup
r21 - 10k rotary encoder pullup
r22 - 470r frequency input dropper
r23 - 10k frequency input voltage divider
r24 - 10k frequency input voltage divider

rv1 - 10k preset frequency input voltage divider

u3 = tl431

q1 - 4673 (bc557c)
q2 - c945 (bc547)
q3 - c945 (bc547)

c1 - 22pf for crystal
c2 - 22pf for crystal
c3 - 100nf
c4 - 10nf
c5 - 10uf 16v
c6 - 10uf 16v
c7 - 100nf
c8 - 100nf
c9 - 100n frequency input DC blocker

and post 349 in this thread has a good picture you can zoom in on and see the colours of the resistors if needed
http://www.badcaps.net/forum/showthread.php?t=50720&highlight=esr+tester&page=18 (http://www.badcaps.net/forum/showthread.php?t=50720&highlight=esr+tester&page=18)
Title: Re: $20 LCR ESR Transistor checker project
Post by: almamater on September 23, 2016, 08:29:18 am
 :-+  :-+  :-+ uouu! Thank you so much! I searched in this thread.. and i did not found this info. Sorry, my bad.
Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 23, 2016, 08:53:33 am
:-+  :-+  :-+ uouu! Thank you so much! I searched in this thread.. and i did not found this info. Sorry, my bad.
Thank you

Build the kit up and let us know how you get on what a lot of people have found is that these testers dont come with firmware on the atmega 328p ic so we have to re programe it ourselves but you may be lucky once you have built it let us know how you get on you will also need to calibrate it too once built.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 23, 2016, 09:17:09 pm
It's alive. ;D The 324/644/1284 dev board is running a preliminary 1.25m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: PedroDaGr8 on September 24, 2016, 12:34:51 am
It's alive. ;D The 324/644/1284 dev board is running a preliminary 1.25m.

I can't wait for this to trickle out. I know this is a huge undertaking so I am waiting for this to complete before I buy one of these.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Nawual on September 24, 2016, 09:49:10 pm
Hi!,i want to buy one,any device?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: almamater on September 25, 2016, 10:11:15 am
Build the kit up and let us know how you get on what a lot of people have found is that these testers dont come with firmware on the atmega 328p ic so we have to re programe it ourselves but you may be lucky once you have built it let us know how you get on you will also need to calibrate it too once built.

Hello, it is done, I soldered all components, a few photos:
(http://s13.postimg.org/zejbjjv4j/IMG_0644.png) (http://postimg.org/image/zejbjjv4j/)
(http://s13.postimg.org/ma95t4doz/IMG_0634.png) (http://postimg.org/image/ma95t4doz/)
(http://s13.postimg.org/v6jxx24b7/IMG_0635.png) (http://postimg.org/image/v6jxx24b7/)
(http://s13.postimg.org/sqmpwybmb/IMG_0636.png) (http://postimg.org/image/sqmpwybmb/)
(http://s13.postimg.org/sf59k6v6b/IMG_0637.png) (http://postimg.org/image/sf59k6v6b/)
(http://s13.postimg.org/gejtjgnrn/IMG_0638.png) (http://postimg.org/image/gejtjgnrn/)
(http://s13.postimg.org/twqpvqzwz/IMG_0639.png) (http://postimg.org/image/twqpvqzwz/)
(http://s13.postimg.org/rtgao3043/IMG_0640.png) (http://postimg.org/image/rtgao3043/)
(http://s13.postimg.org/6l2m6nln7/IMG_0641.png) (http://postimg.org/image/6l2m6nln7/)
(http://s13.postimg.org/jqi4crfir/IMG_0642.png) (http://postimg.org/image/jqi4crfir/)
(http://s13.postimg.org/x8p0p1ro3/IMG_0643.png) (http://postimg.org/image/x8p0p1ro3/)

Differences:
The C5 and C6 capacitors, in the STJ list they are 10uF 16v caps, but i have received 100uF 25v. The seller gave me this PDF: Link  (http://115.28.16.44:81/file/4660.pdf)

Now is time to connect a 9v battery and see what happens!
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 25, 2016, 11:00:19 am
Build the kit up and let us know how you get on what a lot of people have found is that these testers dont come with firmware on the atmega 328p ic so we have to re programe it ourselves but you may be lucky once you have built it let us know how you get on you will also need to calibrate it too once built.

Hello, it is done, I soldered all components, a few photos:
(http://s13.postimg.org/zejbjjv4j/IMG_0644.png) (http://postimg.org/image/zejbjjv4j/)
(http://s13.postimg.org/ma95t4doz/IMG_0634.png) (http://postimg.org/image/ma95t4doz/)
(http://s13.postimg.org/v6jxx24b7/IMG_0635.png) (http://postimg.org/image/v6jxx24b7/)
(http://s13.postimg.org/sqmpwybmb/IMG_0636.png) (http://postimg.org/image/sqmpwybmb/)
(http://s13.postimg.org/sf59k6v6b/IMG_0637.png) (http://postimg.org/image/sf59k6v6b/)
(http://s13.postimg.org/gejtjgnrn/IMG_0638.png) (http://postimg.org/image/gejtjgnrn/)
(http://s13.postimg.org/twqpvqzwz/IMG_0639.png) (http://postimg.org/image/twqpvqzwz/)
(http://s13.postimg.org/rtgao3043/IMG_0640.png) (http://postimg.org/image/rtgao3043/)
(http://s13.postimg.org/6l2m6nln7/IMG_0641.png) (http://postimg.org/image/6l2m6nln7/)
(http://s13.postimg.org/jqi4crfir/IMG_0642.png) (http://postimg.org/image/jqi4crfir/)
(http://s13.postimg.org/x8p0p1ro3/IMG_0643.png) (http://postimg.org/image/x8p0p1ro3/)

Differences:
The C5 and C6 capacitors, in the STJ list they are 10uF 16v caps, but i have received 100uF 25v. The seller gave me this PDF: Link  (http://115.28.16.44:81/file/4660.pdf)

Now is time to connect a 9v battery and see what happens!

Hopefully yours will have the firmware on it already i have two of these testers one is all original as in 8 mhz crystal and original firmware the second one ive modded a bit has 16 mhz crystal a diffrent voltage regulator and a copy of the version 2 16 mhz firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: almamater on September 25, 2016, 11:38:10 am
Yes it have Firmware! ;D It says that i must calibrate first..
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 25, 2016, 11:46:34 am
Yes it have Firmware! ;D It says that i must calibrate first..

Thats great they may of sorted the issue out then too calibrate just put a capacitor to pin 1 and pin 3. This capacitor
should have a good quality factor and should have a capacity between 100nF and 20µF. It should
be a film capacitor. (copied from tester manual pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: almamater on September 25, 2016, 12:56:32 pm
Ok, the Firmware asks to short the probes (3), then to isolate them and dont asks for any capacitor..

With a multimeter and one 6800uF capacitor, i read ~6480uF. With this tester i read ~6600uF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 25, 2016, 01:11:57 pm
ok just checked my origanal tester try going into self test using rotery encoder with all three probes shorted then it will say issolate probs do that then after a few more tests it will say 1-3 100nf add the cap then and let test run
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 25, 2016, 04:10:22 pm
It's alive. ;D The 324/644/1284 dev board is running a preliminary 1.25m.

After testing most stuff I've released 1.25m:
- A lot of changes to support the ATmega 324/644/1284.
- Modified test resistor management to support variable port pins.
- Added software option for probe color coding.
- Centralized color management.
- Added file listing settings for various tester versions/clones.
- Fixed small issue with 24x24 VP symbol bitmap in config.h. Reported by
  lordstein@EEVblog and hapless@EEVblog.

I had a quick look into the ESR issue with the 220nF cap and 16MHz MCU clock. I got one tester with the same issue, but also two which are fine (328@20MHz and 644@16MHz). Some fringe case? :-//

For the next version I plan to add some 324/644/1284 specific features, like hardware SPI.
Title: Re: $20 LCR ESR Transistor checker project
Post by: milamber on September 25, 2016, 05:36:31 pm
Hi, I am using the AY-AT with "AY-AT ESR tester (SVN684) - v2.zip" with 16MHz Quarz.

The unit wants to calibrate nearly every second measurement / button press after turning it on. Even if I finish the calibration successfully, turn it off (without unpowering) and turn it on again.

Is that normal?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 25, 2016, 05:58:00 pm
Have you done the calibration as explained in Karl-Heinz' documentation?
Title: Re: $20 LCR ESR Transistor checker project
Post by: milamber on September 25, 2016, 07:32:09 pm
Have you done the calibration as explained in Karl-Heinz' documentation?
I only followed the instructions displayed on the device display: 
- short all 3 pins for calibration
- remove the wiring
wait for the calibration success message. Tried that several times because selftest was automatically issued again.

Now I RTFM, startet the calibration from the menu, added a 220nf and 22nf ceramic capacitor during test and everything seems to work fine.  :)
Thanks for the hint.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Nawual on September 25, 2016, 08:07:29 pm
Hello, i want to buy one but I can not decide, any suggestion?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 26, 2016, 03:55:55 am
Hello, i want to buy one but I can not decide, any suggestion?

Hi Nawual. Welcome to the forums. Here's a recent summary of the prevalent versions, which might help you narrow down what you like:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1023260/#msg1023260 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1023260/#msg1023260)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 26, 2016, 01:04:22 pm
I think, you've copied your old config_328.h. Replace "LCD_ST7735_SPI" with "LCD_ST7735" and add:
Code: [Select]
#define LCD_SPI_BITBANG                 /* bit-bang SPI interface */

Please see Clones for the settings. Those changes are made to support bit-bang and hardware SPI in the next version, simply by setting LCD_SPI_BITBANG or LCD_SPI_HARDWARE. The ATmega328 based testers can only use bit-bang SPI.

Edit: OP deleted his post, but my answer will stay, just in case someone else runs into the same issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 26, 2016, 01:15:45 pm
Hi, madires! Thank you for the new version! I deleted the post because itself dealt with a problem. Everything is normally compiled. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: packetbob on September 27, 2016, 03:18:04 am
I started reading this thread around the time flywheelz posted about the one he bought:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1007286/#msg1007286 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1007286/#msg1007286)

I thought it would be pretty handy so I ordered one from the same place...
Some how it managed to get to me less than 3 weeks after I ordered it....

Based on flywheelz experience I was paranoid about getting the SRV05-4 diode array correctly oriented. Mine had the smallest of little specs to indicate pin 1. I double it checked against what flywheelz mentions here about identifyign the pins:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1008486/#msg1008486 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1008486/#msg1008486)

It worked as soon as I powered it up. Then I decided that I should try some of the other firmware and boost the clock speed. So I replaced the 8 Mhz crystal with a 16 Mhz. I then followed flywheelz note in this message to wire up some header pins and use an Aruduino UNO as a programmer:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1021401/#msg1021401 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1021401/#msg1021401)

I then used the 16 Mhz version of the firmware I found here: (Updated with correct link 09/27/2016)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1009936/#msg1009936 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1009936/#msg1009936)

Everything seems to work like a charm. However since I figured that the existing ATMEGA328P chip may be marginal at the higher speed I used a new 328P that I had. This way I also had the working code on the original chip in the event I borked it all up. I did clean off the flux from soldering with isopropyl alcohol. And while I didn't think I needed a case for it I did end up mounting it on a piece of 1/4" MDF along with a clip to hold the battery and a piece of aluminum strip to short out caps before testing them. And some labels... And I bought a knob for the encoder...

Going forward, I need to read through the thread again to figure out what other versions of the software exist (it is a long thread) and play with them. I believe I am using stj's SVN684 right now.

I case you noticed the big ass'd transistor I am testing in the pictures. It is a 2N107. One of the first electronics projects I ever built was a small transistor amplifier back in the early 70's. It was based on a circuit that I believe I got from The Boy's Third Book of Radio and Electronics (by Alfred Morgan). Don't have the amplifier anymore but still have a couple working 2N107s (according to the testor!!!)

My thanks to everyone that added to this thread.....
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 27, 2016, 05:40:46 am
@packetbob,

Nice write up of your experience and your success story.  I like the simple platter you made for the little guy, neat  :-+

Is it possible you've mixed up the link to GM328x 16Mhz firmware?  I believe that unit has monochrome LCD and ours is AY-AT unit with TFT Color LCD.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alte on September 27, 2016, 02:59:50 pm
There is a case for the AY-AT on thingiverse; http://www.thingiverse.com/thing:1633951 (http://www.thingiverse.com/thing:1633951)
It's simple but a good fit and protects your tester form dust when not in use.
All credit goes to the designer  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on September 27, 2016, 10:20:37 pm
There is a case for the AY-AT on thingiverse; http://www.thingiverse.com/thing:1633951 (http://www.thingiverse.com/thing:1633951)
It's simple but a good fit and protects your tester form dust when not in use.
All credit goes to the designer  :-+

I guess its good for those with makerbot/3d printer but I tried to order it and they want $25.33  :-- no thanks.  Better and cheaper $6.88 to get [this one] (http://www.ebay.com/itm/Case-Shell-for-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-/112108340467?hash=item1a1a2d84f3:g:pfkAAOSw3ihXTUUV) but do need to modify it a little like [this] (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1025647/#msg1025647)  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: packetbob on September 28, 2016, 12:54:05 am
Is it possible you've mixed up the link to GM328x 16Mhz firmware?  I believe that unit has monochrome LCD and ours is AY-AT unit with TFT Color LCD.

You are correct...
I updated the link in my earlier post..
The firmware for the AY-AT that I used is at:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1009936/#msg1009936 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1009936/#msg1009936)

Thanks for catching that.....
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 28, 2016, 09:25:17 am
Hi, friends! For a tester of DIY Kit "AY-AT" it is necessary to change in config_328.h  line
#define LCD_RES PD4 on
#define LCD_RES PD0 
  According to the diagram of a tester the output 2 processors is connected to contact of RESET of the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 28, 2016, 09:49:07 am
That makes sense, since the frequency counter requires T0, which is PD4 in case of the ATmega328. I'll update the Clones file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 28, 2016, 10:00:02 am
Some ST7735 displays will work if to leave a line without changes
#define LCD_RES PD4. But there are displays which will have only the white screen in case of switching on.
My friend who has the same tester faced such problem.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 28, 2016, 11:01:45 am
Then we should keep "#define LCD_RES  PD0". If LCD_RES is set to PD4, which isn't connected to the LCD module, the pin doesn't contol anything, besides creating some additional heat in the bottom resistor of the frequency counter's input voltage divider. So setting PD0 would increase the run time of the battery ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 28, 2016, 11:12:31 am
So setting PD0 would increase the run time of the battery ;)

Very correct note! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: idwr on September 29, 2016, 04:03:14 am
I have AY-AT_ST7735   modul tester TFT.

an information in forum latest firmware:
mega328_color_kit_AY-AT_ST7735_trendy_1.24m

and we've tried, okay

but I have not found .....

DS1820 tester
IR tester
DHT11 tester

if anyone has already tried, firmware with DS/IR/DHT11 tester....?
thank you

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 29, 2016, 07:28:19 am
Please download the source ( https://github.com/svn2github/transistortester/tree/master/Software/Markus ) and read the README file. The firmware doesn't support the two sensors, but an IR receiver module and several RC protocols.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on September 29, 2016, 04:11:56 pm
I bought an already made GM328R from eBay which works but looks like it was made by a drunken Boy Scout on a Friday afternoon - all the components are mis-aligned.  Anyway it works.  I want to upgrade so a few quick questions:

1. Will the new firmware that madires just linked to (vn 1.25m I think), work on the GM2328R?
2. I have some 20 MHz but no 16 MHz Xtals, can I fit a 20 MHz Xtal and use the new (or another) firmware or would you recommend 16 MHz?
3. I just bought a TL866A programmer so I'm new to it, it starts to read the ATmega328 and then comes up with "read error code 31"; is this because the AVR is locked?
4. I think I can reprogram by erasing, then load the data and eeprom areas (as Intel hex), and then set the fuses, right?

Thanks for any help in advance.

BTW, I'm a self-employed hardware / PCB designer.  If someone sends me a schematic for the new circuit, I will design the PCB for the community.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 29, 2016, 04:46:22 pm
1. Will the new firmware that madires just linked to (vn 1.25m I think), work on the GM2328R?
2. I have some 20 MHz but no 16 MHz Xtals, can I fit a 20 MHz Xtal and use the new (or another) firmware or would you recommend 16 MHz?
3. I just bought a TL866A programmer so I'm new to it, it starts to read the ATmega328 and then comes up with "read error code 31"; is this because the AVR is locked?
4. I think I can reprogram by erasing, then load the data and eeprom areas (as Intel hex), and then set the fuses, right?

Should work if it got a supported display (I'd guess it's a ST7565) and the 20MHz crystal is also fine with the m-firmware. Some clone vendors lock the MCU, which is plain stupid since the firmware is open source. And yes, you need to perform a "chip erase" to reset the lock bits.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 29, 2016, 04:51:12 pm
I bought an already made GM328R from eBay which works but looks like it was made by a drunken Boy Scout on a Friday afternoon - all the components are mis-aligned.  Anyway it works.  I want to upgrade so a few quick questions:

1. Will the new firmware that madires just linked to (vn 1.25m I think), work on the GM2328R?
2. I have some 20 MHz but no 16 MHz Xtals, can I fit a 20 MHz Xtal and use the new (or another) firmware or would you recommend 16 MHz?
3. I just bought a TL866A programmer so I'm new to it, it starts to read the ATmega328 and then comes up with "read error code 31"; is this because the AVR is locked?
4. I think I can reprogram by erasing, then load the data and eeprom areas (as Intel hex), and then set the fuses, right?

Thanks for any help in advance.

BTW, I'm a self-employed hardware / PCB designer.  If someone sends me a schematic for the new circuit, I will design the PCB for the community.

i have this programmer as you say use intel hex for the files
This is the picture with the correct fuse settings for the programmer.
https://www.dropbox.com/s/zqacxby4ayngy2c/Fuses%20on%20TL866A.jpg?dl=0 (https://www.dropbox.com/s/zqacxby4ayngy2c/Fuses%20on%20TL866A.jpg?dl=0)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on September 29, 2016, 05:37:05 pm
I've posted a picture of mine, can someone please help me get the right hex files for the new vn m for a 20 MHz Xtal?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on September 29, 2016, 05:42:17 pm
I've posted a picture of mine, can someone please help me get the right hex files for the new vn m for a 20 MHz Xtal?

Thanks

I have two of these exact testers one original firmwre 8mhz crystal one 16 mhz and v2 firmware i will attach the firmware i used but not sure if it supports the 20mhz crystal maybe stj can advise as its his firmware files
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 29, 2016, 06:03:13 pm
the K firmware does not support 20MHz, the M (Madires) firmware does.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on September 29, 2016, 06:09:13 pm
Thanks for all the help guys.  I probably need to place a Digikey order in the next day or so so I've added some 16 MHz Xtals to the cart then I'll have 8, 16 and 20 MHz options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: fz on October 01, 2016, 03:19:36 am
Hi everyone,

A great forum! I purchased an AY-AT clone of this tester from http://www.ebay.com/itm/182153844649 (http://www.ebay.com/itm/182153844649) based on the recommendations here. It booted up fine after I put it together. I then did a dumb thing: I changed the frontcolor and it now doesn't display anything |O

I tried a few things, including setting the test to selftest mode, as suggested on the seller's the ebay site. But it was very hard to know what I was doing without the display:( My questions are 1) is there a way to reset the display settings on this thing, and 2) if not how can I get the display back?

Many thanks,

feng
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on October 01, 2016, 03:32:08 am
Try this with unit off.

Only other way is to reflash eeprom.

Update:  If above don't work, then try 5 clicks in step 2.  The idea is you enter the Fontcolor in the dark.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on October 01, 2016, 05:07:01 am
sounds like the code needs a patch to prevent the background and forground from being set to the same value or even wihin a couple of points either way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: milamber on October 01, 2016, 09:33:25 am
How are your experiences with the acryl case?
http://www.ebay.de/itm/112108340467?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.de/itm/112108340467?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

Is the ZIF socket lever still acceptably usable?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on October 01, 2016, 10:38:02 am
How are your experiences with the acryl case?
http://www.ebay.de/itm/112108340467?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.de/itm/112108340467?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

Is the ZIF socket lever still acceptably usable?

I havnt got this case but i would modify it so you can get too the lever easily and also the smd test pads on the pcb.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on October 01, 2016, 05:59:58 pm
How are your experiences with the acryl case?
http://www.ebay.de/itm/112108340467?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.de/itm/112108340467?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

Is the ZIF socket lever still acceptably usable?

I havnt got this case but i would modify it so you can get too the lever easily and also the smd test pads on the pcb.

See my post 2673, I've modified the case a little bit to acces the lever and the SMD pad.
You can make an longer handle to the lever, but I didn't like that.
I like the case when modified.
There is room for a 9 Volt battery.
Maybe I make an SPI interface in the case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: fz on October 01, 2016, 11:43:30 pm
Try this with unit off.
  • Press and Hold for 2 to 3 seconds, unit should turn on and get into Menu.
  • Rotate to Left (counter-clockwise) 4 Clicks
  • Press down once
  • Rotate Left few clicks until you see red
  • Press down once to go to next color
  • Press and Hold when done.

Many thanks, Flywheelz, it worked on the first try :-+ 4 clicks gets you to frontColor.

Only other way is to reflash eeprom.

Update:  If above don't work, then try 5 clicks in step 2.  The idea is you enter the Fontcolor in the dark.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on October 02, 2016, 05:59:21 pm
OK, big thanks to all here, I got my GM328R running on a 16 MHz crystal today. 

I used a TL866A programmer and that gave me issues because I have a Windows 10 PC that has USB 3.0 on the main board plus I have a USB 3.0 powered hub that is fussy about what it works with.  Anyway the TL866A didn't like being connected via the hub and gave me all sorts of weird error messages until I noticed that the TL866A App had a 'Hardware Error' message at the bottom; switching to a port connected directly to my PC's motherboard solved the TL866A issue and then I just erased the AVR and copied the files, .hex to code and .eep to data plus the fuse settings that vinceroger recommended and it worked just fine.

The Atmel datasheet says that CKSEL[3:1] should be 111 for 8-16 MHz but it didn't run when I set them to that so I stuck with 100, any ideas why that's the case?

Also the new calibration routine caught me out as it wanted a second capacitor (12-30 nF) after the >100 nF one.

I attached a picture to show my unit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on October 02, 2016, 08:01:09 pm
now test the new function by putting your old crystal into the test socket.  8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on October 02, 2016, 08:58:32 pm

The Atmel datasheet says that CKSEL[3:1] should be 111 for 8-16 MHz but it didn't run when I set them to that so I stuck with 100, any ideas why that's the case?


Glad to see you gt it running OK. I was going to suggest that there should have been no error on the TL866 even with a locked chip.

That reference in the datasheet is for using a low power crystal oscillator. The CKSEL for the Full Swing crystals that we use are in the following section.
I am also impressed that you looked at the datasheet. I find that most problems people encounter with microprocessors could have been avoided if the datasheet had been consulted.

Graham
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on October 02, 2016, 09:59:58 pm
Stj, I put a 4 MHz Xtal into the socket and it detected it correctly :D  I also saw 'STJ' at the end of the Vn credits

Graham, I'm an embedded design engineer and I read datasheets all the time but I obviously didn't read the ATMega328P one properly or I would have seen that there was a non-low-power oscillator section.

Ted
Title: Re: $20 LCR ESR Transistor checker project
Post by: pickit2 on October 03, 2016, 08:47:06 am
hi I got a kit but the FTF is not working it was damaged in the post.
While I am waiting for a replacement, I noticed it is not the same pinout, as most small displays on the market.
This is how the pins on the display connect to the tester, the display has no marking as to pin functions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2016, 09:24:19 am
Maybe a ST7735 based display. I've seen them with different pin headers (8 and 9 pins) and various pinouts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on October 03, 2016, 09:43:21 am
hi I got a kit but the FTF is not working it was damaged in the post.
While I am waiting for a replacement, I noticed it is not the same pinout, as most small displays on the market.
This is how the pins on the display connect to the tester, the display has no marking as to pin functions.

Hi have you got a link too the kit you purchased thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: pickit2 on October 03, 2016, 10:05:24 am
http://www.ebay.co.uk/itm/2016-GM328-Transistor-Tester-Diode-ESR-Meter-PWM-Square-Wave-Generator-J4L5-/371667707701?var=&hash=item56891f2735:m:mRtFR9MCmBteJw-J27eXjGA (http://www.ebay.co.uk/itm/2016-GM328-Transistor-Tester-Diode-ESR-Meter-PWM-Square-Wave-Generator-J4L5-/371667707701?var=&hash=item56891f2735:m:mRtFR9MCmBteJw-J27eXjGA)

I got the kit version on this. but from another seller, details are at workshop, This is the circuit sent by the seller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nour on October 04, 2016, 08:01:37 am
Hi,
I am very impressed by the amount of pages this thread have ^-^, but I am really very confused when it comes to find the thing that I am searching for.

I am looking for the schematic, eagle files, circuit diagram anything :-\ :-//
Can any one help and post those stuff on the the very first page or here after my reply(if there is any at all in this thread!!) of course I am talking about LC meter thing ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on October 04, 2016, 09:48:19 am
Hi,
I am very impressed by the amount of pages this thread have ^-^, but I am really very confused when it comes to find the thing that I am searching for.

I am looking for the schismatic, eagle files, circuit diagram anything :-\ :-//
Can any one help and post those stuff on the the very first page or here after my reply(if there is any at all in this thread!!) of course I am talking about LC meter thing ;D

what meter do you have?
Title: Re: $20 LCR ESR Transistor checker project
Post by: nour on October 04, 2016, 09:54:29 am
Hi,
I am very impressed by the amount of pages this thread have ^-^, but I am really very confused when it comes to find the thing that I am searching for.

I am looking for the schismatic, eagle files, circuit diagram anything :-\ :-//
Can any one help and post those stuff on the the very first page or here after my reply(if there is any at all in this thread!!) of course I am talking about LC meter thing ;D

what meter do you have?

I am sorry, what are you talking about?

I am asking about schematics for LC meter design,
Is there any thing like that in this thread?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on October 04, 2016, 10:24:27 am
Hi,
I am very impressed by the amount of pages this thread have ^-^, but I am really very confused when it comes to find the thing that I am searching for.

I am looking for the schismatic, eagle files, circuit diagram anything :-\ :-//
Can any one help and post those stuff on the the very first page or here after my reply(if there is any at all in this thread!!) of course I am talking about LC meter thing ;D

what meter do you have?

I am sorry, what are you talking about?

I am asking about schematics for LC meter design,
Is there any thing like that in this thread?

manual pdf link im sure this has a schematic in it
https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 04, 2016, 02:13:00 pm
I am asking about schematics for LC meter design,
Is there any thing like that in this thread?

https://github.com/svn2github/transistortester/tree/master/Hardware
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mek on October 04, 2016, 08:27:18 pm
Hi, all,
I just registered to ask about my problem with a Chinese clone of this meter. I bought this one (http://www.ebay.com/itm/231921097471?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT) from ebay recently. I wanted to measure ESR of a cap and forgot it was still charged (25V) which ruined the meter, it would not even turn on. I replaced the 7805 and now the meter turns on but displays bogus data - with no component to test inserted, it shows "Testing..." and after a longer while it shows it detected "BJT-NPN" with beta 1.5M or so, which is like :palm: and it is the same even if shorting pins 1-2-3.
I would like to fix the meter if possible. Does this look like the AVR is fried? I cannot replace it, it has 32 pins and is without a socket and in the smallest possible SMD package of course :(
I also knew that someday this happens that I forget to discharge capacitor before testing, but not that it will be anytime soon |O Ok, so I thought, is there no possible protection from such mistake? If it is, why is it not part of the original circuit? Or is it optional and the Chinese do not include it to cut cost and increase sales? Well, they were successful because I liked the meter and still need an LCR-ESR meter so I ordered another one (thank god they are so cheap).
What are my options in fixing this meter, can anyone suggest, please?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on October 04, 2016, 08:57:26 pm
Quote
What are my options in fixing this meter, can anyone suggest, please?
Wait for someone else to reply but couldn't you just buy a new ATMega328P chip and reprogram it, what else could be wrong?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on October 04, 2016, 09:07:16 pm
post internal foto's

you need to replace the atmel with hot air and obviously program the replacement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on October 05, 2016, 02:41:31 am
I would like to fix the meter if possible. Does this look like the AVR is fried? I cannot replace it, it has 32 pins and is without a socket and in the smallest possible SMD package of course :(

It does sound like the ATmega is fried and is the most common thing to go when connecting a charged capacitor. As stj said, you'll need a hot air station to replace the chip.

Quote
Ok, so I thought, is there no possible protection from such mistake? If it is, why is it not part of the original circuit? Or is it optional and the Chinese do not include it to cut cost and increase sales?

There is a way to protect the chip from such a mistake and, yes, it's an optional feature of the original design (and described in the documentation). Of course, it costs less not to include optional parts. However, just this year someone in China made a version that incorporates optional features including input protection.

Here's an example of one: http://www.ebay.com/itm/371667156523 (http://www.ebay.com/itm/371667156523)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 05, 2016, 08:46:01 am
Hi, madires! Checked operation of a tester of AY-AT ST7735 at a frequency of 20 MHz. All functions work much quicker, than with quartz 8 MHz. The generator is capable to give a signal with a frequency of 5 MHz, and the frequency counter can measure signal frequency to 10 MHz!  :-+ An example on photos which I apply. :)
There are problems in case of measurement of the low-impedance resistors and inductance. I will try to show them in the following post.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 05, 2016, 01:47:58 pm
There are problems in case of measurement of the low-impedance resistors and inductance. I will try to show them in the following post.

Unusual result of measurement of inductivity 240 µH at a frequency of quartz of 20 MHz. Also uncertainly the low-impedance resistors are defined. An example on a photo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 05, 2016, 03:27:43 pm
Thanks for the report! I'll check if I'm able to reproduce the issues.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jm_araujo on October 05, 2016, 11:34:10 pm
Hi, friends! For a tester of DIY Kit "AY-AT" it is necessary to change in config_328.h  line
#define LCD_RES PD4 on
#define LCD_RES PD0 
  According to the diagram of a tester the output 2 processors is connected to contact of RESET of the display.

I have a AY-AT kit and being a bit lazy installed this version: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1016572/#msg1016572 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1016572/#msg1016572) and didn't work, only got a white screen.

After seeing your message I decided to compile my own with the suggested change and it now works fine! My display must be the same as your friend's!
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on October 06, 2016, 01:37:36 am
Checked operation of a tester of AY-AT ST7735 at a frequency of 20 MHz. All functions work much quicker, than with quartz 8 MHz. The generator is capable to give a signal with a frequency of 5 MHz, and the frequency counter can measure signal frequency to 10 MHz!

Excellent. I guess I'll have to upgrade mine at some point.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 06, 2016, 06:38:48 am
Hi, friends! :D If it is interesting to you, then I on pages of the topic made comparing of the software from Karl-Heinz Kübbeler and
Markus Reschke. The forum is Russian-speaking, but I think that according to photos it will be clear without the translation. I hope that this information will help two dear authors of this project to improve operation of a tester. Once again big gratitude for huge work!
The topic contains only 3 pages, comparing of firmwares begins with the 2nd page (a post #703275). Link to the topic http://vrtp.ru/index.php?showtopic=26994&st=0 (http://vrtp.ru/index.php?showtopic=26994&st=0)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 06, 2016, 11:03:47 am
Nice side-by-side comparison! Thanks indman!
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on October 06, 2016, 02:22:46 pm
Just compiled and flashed Trendy 1.25m for my MK-328 and fitted a 16Mhz Crystal.
Removed options for "Rotary Encoder"

Just a quick question, is it correct that it cycles through the tests rather than display it on the screen and then switch off, also I have to double press the Test button to enter the menu is this right?

Video attached.

If anyone wants this compiled for the MK-328 please let me know and I'll attach it.

https://www.youtube.com/watch?v=A5aFFacIEFg (https://www.youtube.com/watch?v=A5aFFacIEFg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on October 06, 2016, 04:28:43 pm
Just compiled 1.12k from the latest SVN for MK-328 with 16Mhz and Crystal test if anyone wants me to attach it here please ask.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 06, 2016, 04:48:14 pm
Just a quick question, is it correct that it cycles through the tests rather than display it on the screen and then switch off, also I have to double press the Test button to enter the menu is this right?

The firmware has two operation modes. When you power the tester on with a short key press, it runs in continous mode and will power off after five misses. You can change CYCLE_MAX in config.h to change the number. With a long key press the tester runs in hold-mode, i.e. it stays on und requires you to press the button to continue. It's explained in the README. Yes, to enter the menu you create a short between all three probes or press the button twice. With a rotary encoder you also have the option to turn left for entering the menu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on October 06, 2016, 05:26:19 pm
Just a quick question, is it correct that it cycles through the tests rather than display it on the screen and then switch off, also I have to double press the Test button to enter the menu is this right?

The firmware has two operations modes. When you power the tester on with a short key press, it runs in continous mode and will power off after five misses. You can change CYCLE_MAX in config.h to change the number. With a long key press the tester runs in hold-mode, i.e. it stays on und requires you to press the button to continue. It's explained in the README. Yes, to enter the menu you create a short between all three probes or press the button twice. With a rotary encoder you also have the option to turn left for entering the menu.

Thanks for the reply, yeah it's all working perfectly.
Just trying out the K firmware as well, having a bit of a mess around with it today  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on October 06, 2016, 07:37:52 pm
Hi, friends! For a tester of DIY Kit "AY-AT" it is necessary to change in config_328.h  line
#define LCD_RES PD4 on
#define LCD_RES PD0 
  According to the diagram of a tester the output 2 processors is connected to contact of RESET of the display.

I have a AY-AT kit and being a bit lazy installed this version: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1016572/#msg1016572 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1016572/#msg1016572) and didn't work, only got a white screen.

After seeing your message I decided to compile my own with the suggested change and it now works fine! My display must be the same as your friend's!

Please can you post your compiled version. I have the same problem with the M Version.
I don't have experience with compiling.
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 07, 2016, 02:22:27 am
Hi, friends! :D If it is interesting to you, then I on pages of the topic made comparing of the software from Karl-Heinz Kübbeler and
Markus Reschke. The forum is Russian-speaking, but I think that according to photos it will be clear without the translation. I hope that this information will help two dear authors of this project to improve operation of a tester. Once again big gratitude for huge work!
The topic contains only 3 pages, comparing of firmwares begins with the 2nd page (a post #703275). Link to the topic http://vrtp.ru/index.php?showtopic=26994&st=0 (http://vrtp.ru/index.php?showtopic=26994&st=0)

From those pages, it looks like the m firmware has gained some cyrillic support while I wasn't looking (and it also looks like at least one of the fonts has the two halves of the resistor symbol interchanged)... interesting.  :popcorn:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 07, 2016, 10:06:10 am
I'd add the cyrillic font and texts in the firmware, if someone would send me the files. ;) Several users already asked for cyrillic support.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 07, 2016, 12:20:56 pm
If you do that, I feel I should mention that for complete support it might be a good idea to have units translatable as well. I know for a fact that in the former Soviet bloc SI units were not always used, and some (older) people there might be more comfortable with translated versions. I believe even the Greek letter mu for micro had its own (two cyrillic letters?) abbreviation. I also never understood why "Bat." and some other English-only strings is not translatable in either firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jm_araujo on October 07, 2016, 03:14:41 pm
Please can you post your compiled version. I have the same problem with the M Version.
I don't have experience with compiling.
Thanks.

Sure! It's attached. As I've changed my crystal to 20MHz and seems some people change theirs to 16MHz, I include compilations for the 3 different speeds.
My fuses are set as L:0xF7 H:0xD9 E:0x04

All the credits should go to flywheelz for making the changes for AY-AT, and indman for finding the LCD_RES bug.
And of course to madires for all the great work!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mek on October 07, 2016, 09:17:20 pm
post internal foto's

you need to replace the atmel with hot air and obviously program the replacement.
This is it. But even if I manage to replace the atmel, I cannot seem to find the program to flash. This Chinese clone of transistortester is not mentioned in the docs. Am I missing something?
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on October 07, 2016, 09:46:14 pm
Please can you post your compiled version. I have the same problem with the M Version.
I don't have experience with compiling.
Thanks.

Sure! It's attached. As I've changed my crystal to 20MHz and seems some people change theirs to 16MHz, I include compilations for the 3 different speeds.
My fuses are set as L:0xF7 H:0xD9 E:0x04

All the credits should go to flywheelz for making the changes for AY-AT, and indman for finding the LCD_RES bug.
And of course to madires for all the great work!!
Tks I tested 8Mhz it works.inductance seems not functional btw.nice job.tomorrow or monday I'll test the 20 MHz.
Best regards from France :)


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on October 07, 2016, 10:22:56 pm
post internal foto's

you need to replace the atmel with hot air and obviously program the replacement.
This is it. But even if I manage to replace the atmel, I cannot seem to find the program to flash. This Chinese clone of transistortester is not mentioned in the docs. Am I missing something?

the 2x6 holes left of the crystal are for programming,
now we know it's by "Fish8840" we can experiment with a few firmwares to get it right.

before that, who did that disgusting soldering, and messed with the 6 resistors under the cpu?
because that has to be fixed first.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Mek on October 08, 2016, 07:18:42 am
post internal foto's

you need to replace the atmel with hot air and obviously program the replacement.
This is it. But even if I manage to replace the atmel, I cannot seem to find the program to flash. This Chinese clone of transistortester is not mentioned in the docs. Am I missing something?

the 2x6 holes left of the crystal are for programming,
now we know it's by "Fish8840" we can experiment with a few firmwares to get it right.

before that, who did that disgusting soldering, and messed with the 6 resistors under the cpu?
because that has to be fixed first.
It was me. The resistors had strange values while measured in-circuit so I de-soldered some of them to measure out of circuit. Two were OK (according to their values), one was completely wrong so I replaced it with a standard 0.25watt one but that did not help in my problem. It's not visible in the picture, I took it out before taking the photo so the PCB is visible better (maybe I was too naive that only the smd resistors failed?). I only have a standard old 75w soldering gun and one micro-soldering station which has a thicker tip than I would like :-//

//edit: I fixed the resistors, there are no shorts but it didn't help...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on October 08, 2016, 11:48:53 am
Mek,

Ideally, you would use a hot air rework station to remove the Atmel chip but it can be done just with a soldering iron, here's how.

1. Either with some very small cutters or CAREFULLY with an X-Acto knife (you can push the knife tip inbetween two legs and the sharp edge will cut through a leg while the blunt edge pushes against the other pin), cut all the legs off the old Atmel chip LEAVING THEM SOLDERED TO THEIR PADS.
2. With tweezers and the soldering iron, carefully desolder each pin one at a time - don't pull hard with the tweezers, just wait for the solder to melt - it sounds couter-intuitive but you may need to add more solder to each pad/pin at this stage to make it easier for the heat to flow
3. After all pins are removed, use solder wick (that you've previously wiped with a flux pen) to remove the excess solder from the pads - don't pull at the solder wick if it gets stuck to the pads, wait for it to heat up so that it lifts on its own
4. Clean the area with a cotton swab and clear alcohol (I use vodka :D)
5. Put fresh solder on ONE PAD then position the new IC and solder that 1 pad making sure the IC is aligned properly INCLUDING PIN 1 being in the right place
6. Now add solder to a pin on the other side of the IC and check alignment, once alignment is good, solder the remaining pads
7. If any pads are bridged with solder, use the solder wick braid wiped with flux pen and carefully creep up on the pads with excess solder to soak up the excess

You need a good (temperature controlled) soldering iron set to 350 C for lead free solder.  It's also good to have some form of magnifier if you have old eyes like mine.  Leaded solder (if you have any) will use lower temperature (around 310 C) and will be easier to work with

Even if 1 pads lifts, you can usually make it work by soldering that pad last and/or repairing with a piece of wire.

Good luck
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on October 08, 2016, 12:47:32 pm
post internal foto's

you need to replace the atmel with hot air and obviously program the replacement.
This is it. But even if I manage to replace the atmel, I cannot seem to find the program to flash. This Chinese clone of transistortester is not mentioned in the docs. Am I missing something?

the 2x6 holes left of the crystal are for programming,
now we know it's by "Fish8840" we can experiment with a few firmwares to get it right.

before that, who did that disgusting soldering, and messed with the 6 resistors under the cpu?
because that has to be fixed first.
Tom66 has somefirmware posted for a fish8840 tester so this maybe of help i will attach what i found
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mek on October 08, 2016, 01:27:10 pm
Mek,

Ideally, you would use a hot air rework station to remove the Atmel chip but it can be done just with a soldering iron, here's how.

1. Either with some very small cutters or CAREFULLY with an X-Acto knife (you can push the knife tip inbetween two legs and the sharp edge will cut through a leg while the blunt edge pushes against the other pin), cut all the legs off the old Atmel chip LEAVING THEM SOLDERED TO THEIR PADS.
2. With tweezers and the soldering iron, carefully desolder each pin one at a time - don't pull hard with the tweezers, just wait for the solder to melt - it sounds couter-intuitive but you may need to add more solder to each pad/pin at this stage to make it easier for the heat to flow
3. After all pins are removed, use solder wick (that you've previously wiped with a flux pen) to remove the excess solder from the pads - don't pull at the solder wick if it gets stuck to the pads, wait for it to heat up so that it lifts on its own
4. Clean the area with a cotton swab and clear alcohol (I use vodka :D)
5. Put fresh solder on ONE PAD then position the new IC and solder that 1 pad making sure the IC is aligned properly INCLUDING PIN 1 being in the right place
6. Now add solder to a pin on the other side of the IC and check alignment, once alignment is good, solder the remaining pads
7. If any pads are bridged with solder, use the solder wick braid wiped with flux pen and carefully creep up on the pads with excess solder to soak up the excess

You need a good (temperature controlled) soldering iron set to 350 C for lead free solder.  It's also good to have some form of magnifier if you have old eyes like mine.  Leaded solder (if you have any) will use lower temperature (around 310 C) and will be easier to work with

Even if 1 pads lifts, you can usually make it work by soldering that pad last and/or repairing with a piece of wire.

Good luck
Thank you for this detailed how-to. I was planning to use my dremel to cut out the old chip, it might work better than a knife. Anyway, I have to get my hands on a new atmel first :o

Tom66 has somefirmware posted for a fish8840 tester so this maybe of help i will attach what i found
Thank you. I think this is is an older version (the original one says "2.1" on startup) but if no newer is available, it is worth a shot. I bought an avrdragon a while ago (never really got to experimenting with it) but I believe I can use it to push the firmware to the chip once I have it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 08, 2016, 04:25:17 pm
the resistor symbol interchanged)... interesting.  :popcorn:
It was the small error which is already corrected. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on October 08, 2016, 04:44:31 pm
...
4. Clean the area with a cotton swab and clear alcohol (I use vodka :D)
...

Hmm, I thought vodka was for the operator after a successful operation, not the patient. :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on October 08, 2016, 07:03:24 pm
Please can you post your compiled version. I have the same problem with the M Version.
I don't have experience with compiling.
Thanks.

Sure! It's attached. As I've changed my crystal to 20MHz and seems some people change theirs to 16MHz, I include compilations for the 3 different speeds.
My fuses are set as L:0xF7 H:0xD9 E:0x04

All the credits should go to flywheelz for making the changes for AY-AT, and indman for finding the LCD_RES bug.
And of course to madires for all the great work!!

Thank you jm_araujo,
Works fine, I used the 16 Mhz version.
Like to see the M-Version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on October 09, 2016, 04:46:49 pm
Hi, I stopped reading this forum about 6 months ago since I completed my tester.

What exactly is the advantage of increasing the crystal frequency, my original crystal is 8Mhz.  Is there one firmware version that is good for all the different crystals or do you need a specific version for each frequency? 

If you need a different firmware version for each frequency then which firmware version number corresponds for each frequency?

Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on October 09, 2016, 05:17:07 pm
16MHz does more accurate tests and can also test crystals and resonators upto about 10MHz

it is different firmware, it's included in any zips i post.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on October 09, 2016, 06:07:25 pm
Should an SCR be possible to read on the transistor tester?
Specifically a S2514NH. (Attached datasheet).
It shows up just as a 15ohm resistor. (I am suspecting something is wrong with the SCR).
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on October 09, 2016, 06:39:19 pm
This "tester" does not really test components, it simply tries to identify them, meaning that even if does correctly identify the component, there is still a chance that something might wrong with it.

Hi, I stopped reading this forum about 6 months ago since I completed my tester.

What exactly is the advantage of increasing the crystal frequency, my original crystal is 8Mhz.  Is there one firmware version that is good for all the different crystals or do you need a specific version for each frequency? 

If you need a different firmware version for each frequency then which firmware version number corresponds for each frequency?



The firmware version for different crystals stays the same. It is simply compiled with a different parameter for each frequency. If you change your crystal, you need a firmware compiled for it. Currently, only m firmware supports 20MHz, but both support 16 and 8, AFAIK.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on October 09, 2016, 09:07:57 pm
i was refering to the hex files being different.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on October 09, 2016, 09:34:48 pm
Should an SCR be possible to read on the transistor tester?
Specifically a S2514NH. (Attached datasheet).
It shows up just as a 15ohm resistor. (I am suspecting something is wrong with the SCR).

This device is capable of recognizing Thyristors IF the gate current is <~ 5-6mA.
Your SCR requires minimum 20mA so cannot be recognized. Your SCR could well be OK.

Graham
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 10, 2016, 12:37:49 pm
Hi! Tried to use other character set 32x32 instead of 24x24 symbols. Result on a photo. The big or small size can be set, changing value #define to SYMBOL_RESIZE in the ST7735.c file.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 10, 2016, 02:08:17 pm
Some more background info on the symbol sizes in the m-firmware ;) At the moment there are two bitmap sets, 24x24 (horizontal & vertical bit orders) and 32x32 (horizontal only). As larger the symbols as larger the firmware. Based on the display controller you have to select a bitmap with a specific bit order. ILI9341 and ST7735 need horizontal order, and ST7565 is page-wise vertical. For ILI9341 and ST7735 you can change SYMBOL_RESIZE in the driver source file to resize the symbols by that factor. I've choosen the defaults to match the display size. For the ST7735 you can choose between SYMBOLS_24X24_H (default) and SYMBOLS_32X32_H in the config_328.h and change the sizing factor (default: 2) via SYMBOL_RESIZE in ST7735.c.

In case someone likes to draw some nicer symbols, I've written a tool to convert the bitmaps from and to different bit orders, including page-wise grouping.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2016, 04:47:28 pm
There are problems in case of measurement of the low-impedance resistors and inductance. I will try to show them in the following post.

Unusual result of measurement of inductivity 240 µH at a frequency of quartz of 20 MHz. Also uncertainly the low-impedance resistors are defined. An example on a photo.

Currently I'm looking into the inductance measurement issue and found some error in the control logic, causing the delayed check to be run instead of the high current one for a <1mH inductor. The resulting mismatch worsens with the MCU frequency. This problem was introduced with the improvement of the measurement resolution in 1.16m. I'll also fine-tune the offsets.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 14, 2016, 09:58:27 am
Hi, madires! I well understand that measurement of inductivity is not the simple task. The result depends on the frequency of measurement, material of the core, diameter of a wire which wound the coil. I put some more photo, I hope that it will help you with the decision. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 17, 2016, 02:08:47 pm
A few posts ago flywheelz reported some funny ESR business with low value film caps and different MCU clock rates. I'm able to reproduce that and even have some extra fun. flywheelz measured a 220nF cap with 8 and 16 MHz clock rates and the 16MHz tester shows an ESR about twice the value of the 8MHz tester. For a complete desaster I've thrown in additionally a 20MHz tester which shows an ESR about 50% higher than the 8MHz tester. What I've also found is that the 16MHz tester can measure the ESR of low value film caps the 8MHz tester can't. For comparison I've checked all caps with a LCR meter and the ESR values are higher (3.2 @ 1kHz instead of 0.95 for example).

The measurement uses charge/discharge pulses while synchronizing them with the ADC. The 8 and 16MHz testers use the same ADC clock, while the 20MHz got a higher ADC clock, caused by the limited fixed prescalers. So the pulse length stays the same for 8 and 16 MHz clocks (besides the time for switching), but the 16MHz clock will create more harmonics when switching the pulse (a wink from Mr. Fourier). For the 20MHz clock the higher ADC clock seems to mitigate the problem. My guess is, that the switching harmonics of the MCU frequency in relation to the ADC clock creates the different ESR values for low value caps.

Edit: The 20MHz tester can also measure the ESR of low value caps the 8MHz tester can't.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on October 17, 2016, 05:21:19 pm
I have the EZM build with madires' firmware.
Since the unit is able to measure frequency,I'd like to try this.
I should connect the output of ,say, a function gen to the atmega pin pd4 (pin6) as stated in the manual or I could do that with the test leads?
Also what could be the maximum voltage I should apply ?


edit:I think I have to build this additional breakout circuit to measure frequency with my build..Just browsed thru the documentation and it's right there..

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 17, 2016, 06:42:46 pm
Yep, that's the circuit for the simple frequency counter. I wouldn't recommend to go above 5V peak.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2016, 04:53:53 pm
A quick update on the m-firmware. I'm still investigating the inductance measurement. The inductance values from the low current measurement are too high, and the values from the high current measurement are too low. And there are variations across the different MCU clocks. Besides this I've done following:
- Changed FrequencyCounter() to support also ATmega 324/644/1284.
- Fixed error in voltage reference handling for ATmega 324/644/1284.
- Improved detection of turning velocity of rotary encoder to cope with different values of pulses per step or detent.
- Added hardware SPI to all drivers for SPI based displays.

When I'll have solved the inductance puzzle I'll release the new version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on November 12, 2016, 10:57:32 am
Hi, I would like to know if you can use the IR-Sensor and IR-Decode function in an LCR-T4 like this:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867)

Thanks and best regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 12, 2016, 12:19:18 pm
Yes, simply select the IR detector in the menu and connect the IR receiver module to the probe pins as explained in the README file (m-firmware). Of course, the firmware should be compiled with SW_IR_RECEIVER enabled in config.h. If your IR receiver module requires 5V also enable SW_IR_DISABLE_RESISTOR.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on November 12, 2016, 12:38:54 pm
Thanks, that's why I could not find it since I use the trunk firmware.

It is possible to activate it for this trunk firmware ?.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 12, 2016, 02:41:40 pm
Sorry, the k-firmware doesn't support IR receiver modules (yet?).
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on November 13, 2016, 10:33:59 am
Thanks, I have since yesterday investigating how to compile the Markus version to work correctly with this Chinese LCR-T4.

These are the things I have had to change to work decently with my LCT-T4 with 16MHz xtal and installed Pull-UP resistors:

In the Makefile:

FREQ = 16

In the config.h file:

//#define HW_ENCODER
//#define ENCODER_PULSES     2
//#define SW_ENCODER
#define CYCLE_DELAY            12000
#define CYCLE_MAX               1

In the config_328.h file

#define LCD_RESET            PD4            /* port pin used for /RES */
#define LCD_A0                 PD3            /* port pin used for A0 */
#define LCD_SI                  PD1            /* port pin used for SI (LCD's data input) */
//#define LCD_OFFSET_X                       /* enable x offset of 4 dots */
//#define LCD_FLIP_Y                            /* enable vertical flip */
#define LCD_CONTRAST     15              /* default contrast (0-63) */

But I have found more inconveniences than advantages:

The measurement of quartz crystals is lost.
The square wave generator is lost by not having the rotary encoder.
The Spanish language is not available.
To enter the menu, the test leads must be short-circuited.
When you press to check a component, make two measurements.

I would like to know how to modify the last two things, that you can enter the menu with the test button and only take one measurement at a time.

Thank you for everything and greetings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 13, 2016, 01:19:13 pm
You can enter the menu also by pressing the button two times briefly. Please see the README file for the operation modes (continously/auto-hold). I think you're running the tester in continious mode, which doesn't require any button press for cycling. If you press the button, the tester skips the pause between two measurements. You could support the project by translating the text in variables.h into Spanish ;) The squarewave generator of the m-firmware allows you to use the full frequency range, not just a few fixed frequencies from a list. That's the reason for the rotary encoder. Doing that with just the push button would be a nightmare. The "Sampling ADC" is already on my to-do list, but I can't give you any time frame. Since the tester clones are cheap, I'd suggest to get a second one, maybe that nice kit with the rotary encoder. So you can have one for each firmware ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on November 13, 2016, 07:14:50 pm
Actually I have two identical units of the tester, one operative and one damaged in the process of repair (soon I will receive the components to repair it).

Once I have the second unit repaired I will proceed to install the firmware m, so I will have the best of both firmwares.

And I will try to add a rotary encoder even if I have to modify the box where I have it installed.

(http://es.zimagez.com/miniature/img20161105123104.jpg) (http://es.zimagez.com/zimage/img20161105123104.php)

Can you recommend a rotary encoder as small as possible to ask for it on Ebay?

Also I will look at the file variables.h to try to translate it into Spanish in case I can support the project.

I attach a Spanish translation of the file langSPANISH.h of the version k with some modifications in the texts in the measurement of crystals of quartz and in the option meter of frequency for that appears like "Not available".

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 13, 2016, 07:25:57 pm
I'd recommend an ALPS EC11 series rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 13, 2016, 07:38:48 pm
PM'd
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on November 14, 2016, 05:02:46 pm
Hi, thanks to your advice I already bought the rotary encoder, but it will take me a month and a half to come from China.

Meanwhile I will continue to learn and prepare the other components that are needed for installation.

According to the manual I only need two resistors from 10K to Vcc and two other resistors from 1K to PD1 and PD3.

But in some schemes I have seen an additional 100nF capacitors.

For this Chinese Yellow LCR-T4 I need exactly, just the four resistors and the rotary encoder?

In case you are supporting the project I have done the Spanish translation of the firmware m but replacing it with the English in the file variables.h.

So if this file is used to compile with the English language by default the meter will be in Spanish.

Attached file for interested parties.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2016, 06:01:58 pm
Thanks for the Spanish translation! I'll add it to the next release. Basically you only need the four resistors, since the debouncing is done in software. The caps could cause trouble, because the rotary encoder is in parallel with the LCD display (ATmega 328 based testers).
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 14, 2016, 09:46:22 pm
here is me fitting a rotary encoder inplace of the original push-button on a different tester.
it may give you an idea how to do it nicely.  :-/O

http://www.badcaps.net/forum/showthread.php?t=50720 (http://www.badcaps.net/forum/showthread.php?t=50720)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on November 15, 2016, 09:42:59 am
They are very good ideas, I had more or less something in mind, although in my case I will have to make some modifications since the circuit tracks are somewhat different, and it is possible that I also have to make some hole, but the idea is the same .

Thanks and best regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on November 16, 2016, 02:16:33 am
here is me fitting a rotary encoder inplace of the original push-button on a different tester.
it may give you an idea how to do it nicely.  :-/O

http://www.badcaps.net/forum/showthread.php?t=50720 (http://www.badcaps.net/forum/showthread.php?t=50720)

Is there a way to see the images for people who have not registered there? I, for one, would not want to go through the registration process just to look at pictures.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 16, 2016, 06:56:50 am
no, sorry.
i dont have them all on the pc now to re-upload here.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Seekonk on November 17, 2016, 04:59:39 pm
Just found something interesting.  I have a unmodified tester, forget the taobao version no encoder.  Just tried testing some vintage 1N55 diodes.  It returns as a small pf capacitor on one of the unconnected leads. All three of the diodes I tested read OK .417 on a DVM.  Schottky diodes test fine at .206V as well as silicon.  Can't imagine why it can't test germanium.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 17, 2016, 06:03:40 pm
The old firmware versions have a detection problem of some Germanium diodes with very low Vf or a high leakage current. A freezer spray might help. The current versions got some improvements (1.12k trunk, >= 1.24m), especially the m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: siri_ on November 19, 2016, 01:03:50 am
Hi allI  :-DMM

have one of those, and when I power it from a adjsutable power supply, it says "Bat. 10V OK". But i'm supllying it 9V, at least that's what's my multimeter (uni-t ut61E) says...

Is it something that could be a problem or it doesn't matter?

Thanks!

Title: Re: $20 LCR ESR Transistor checker project
Post by: MosherIV on November 19, 2016, 10:28:05 am
Quote
   have one of those, and when I power it from a adjsutable power supply, it says "Bat. 10V OK". But i'm supllying it 9V, at least that's what's my multimeter (uni-t ut61E) says...

Is it something that could be a problem or it doesn't matter?
No problem, it is ok and bear in mind that the values are for indication inly (ie could be way off as you have found)

They have used a cheap zener diode instead of a voltage reference, which leads to the inaccuracy.
Another way to word around it is to run the calibration routine.
(If you replace the zener diode with a voltage reference, you must run the calibration routine)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 19, 2016, 01:12:21 pm
If they've used a cheap zener as external reference all meassurements would be affected. Another cause could be the voltage divider for the battery voltage and some parts in the power section, i.e. a reverse voltage protection diode and a PNP. You can adjust the resistor values of the divider and the voltage offset in the source code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 19, 2016, 02:43:34 pm
that unit uses a TL431
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 19, 2016, 04:08:02 pm
I'd suggest to use a LM4040AIM3-2.5 (SOT-23) or LM4040AIZ-2.5 (TO-92). But that depends on the 5V LDO. The external voltage reference makes only sense if its tolerance is about 10 times better than the LDO's. A cheap TL431 got 1 or 2%.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 19, 2016, 06:46:18 pm
the regulator on that unit is a Holtek HT7550,
it's got good specs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on November 19, 2016, 08:00:49 pm
Hi allI  :-DMM

have one of those, and when I power it from a adjsutable power supply, it says "Bat. 10V OK". But i'm supllying it 9V, at least that's what's my multimeter (uni-t ut61E) says...

Is it something that could be a problem or it doesn't matter?

Thanks!

Sounds very much like a low accuracy resistor in the voltage divider. Does this also happen when you connect a battery?

No problem, it is ok and bear in mind that the values are for indication inly (ie could be way off as you have found)
[...]

I wouldn't say that. If it's way off, the automatic shutoff will not work right, and when running on rechargeable battery power it could mean discharging the battery beyond its limit or using the unit with voltages below the expected 5V on VCC.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on November 19, 2016, 09:00:49 pm
Hi, where can I find a compiled firmware for this tester with a 16MHz crystal?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on November 20, 2016, 09:00:20 am
Hi, where can I find a compiled firmware for this tester with a 16MHz crystal?

Thanks

It's not complicated, you can compile it yourself.

If you need it urgently I enclose one that I have compiled myself version k (698) for crystal of 16MHZ, English language, without Pull-UP resistors and with measurement of activated quartz crystals.

(http://es.zimagez.com/miniature/lcr-t4original16mhz.jpg) (http://es.zimagez.com/zimage/lcr-t4original16mhz.php)

Unzip with WinRar.

A greeting
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on November 21, 2016, 04:04:23 am
16MHz does more accurate tests and can also test crystals and resonators upto about 10MHz

I am in the process of upgrading my crystal to 16MHZ and I am still confused.  In the Karl-Heinz ver. 1.12k manual in the OP_MHZ configuration it says that "The 8 MHz operation is recommended for better resolution of capacity and inductance measurement", so what is it? 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gyro on November 21, 2016, 10:11:46 am
At the time that Karl-Heinz wrote that, the choice was 1MHz or 8MHz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on November 21, 2016, 04:40:11 pm
The 1.12k manual mentions all 3 frequencies, 1MHz, 8MHz and 16MHz with the quote I mentioned above!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 21, 2016, 06:46:42 pm
The measurements of inductance and low value caps is based on measuring time. As higher the MCU clock as higher the resolution of the time measurement. And it also impacts the range limits. With an 1 MHz MCU clock the inductance measurement's lower limit might be around 100µH. With 8 MHz it's about 10µH. These values are for the standard measurement method.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on November 21, 2016, 07:22:48 pm
So what is the resolution and accuracy of the measurements with 16MHz versus 8MHz clock?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 21, 2016, 08:49:17 pm
16 MHz provides twice the resolution of 8 MHz. Take the equations for the measurements and calculate the impact of the higher time resolution. The accuracy with 16 MHz might decrease a little bit in case the measured time is at the mid of a clock cycle of the 8 MHz clock (jitter).
Title: Re: $20 LCR ESR Transistor checker project
Post by: PointyOintment on November 21, 2016, 10:11:15 pm
Anybody know how these devices measure the reverse leakage current of diodes? I checked a diode with one last week and it said "Ir = 2 nA"! How??
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 22, 2016, 11:56:00 am
Very simple ;) A 470k ohms resistor as current shunt and an ADC resolution of about 1mV when using the 1.1V internal bandgap reference: 1mV / 470kOhms = 2nA
Title: Re: $20 LCR ESR Transistor checker project
Post by: ardhuru on November 24, 2016, 06:20:25 pm
Hi guys,

I'm new to AVRs, so please excuse me if I ask some stupid questions.

I wanted to make an absolutely minimal tester (USB powered, no LCD, UART output thru a USB-to-serial adapter, no crystal and Atmega8 based.

I chose ver 1.06k and compiled it for 8MHz, internal, uploaded it with an USBasp and all seemed well.

BUT, I find that the unit auto-repeats for a few cycles (during which it reads components very reliably), and then simply hangs.

I tried it on another Atmega8, very similar results; works for a few cycles, and then hangs. At this point, the only option is to interrupt the power, and then it works for a few cycles of testing again.

Could anybody point me in the right direction?

Many thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 24, 2016, 07:05:15 pm
Please use the trunk version (1.12k) and read Karl-Heinz' documentation (see POWER_OFF option).
Title: Re: $20 LCR ESR Transistor checker project
Post by: ardhuru on November 25, 2016, 07:13:33 am
A thousand thanks! Brilliant!

Instead of using an actual pullup, I just recompiled by enabling the internal pull-ups and it worked flawlessly.

Which brings up the question, why is it optional/configurable? Are there any advantages to disabling the internal pullups?

I havent tried the version 1.12k per your suggestion yet, as I need to fit the code into an Atmega8, with the UART enabled, (and disabling the LCD related code) and I already use up 99.9% flash space with ver 1.06k, so I suspect the 1.12k would not fit.

Thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ardhuru on November 25, 2016, 07:37:25 am
Okay, got the answer to that question in Chapter 5 of the manual. I havent seen much degradation in measurements, so I guess I'll stick with the internal pullups enabled.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lpc32 on November 27, 2016, 11:05:53 am
A few posts ago flywheelz reported some funny ESR business with low value film caps and different MCU clock rates. I'm able to reproduce that and even have some extra fun.
So what's the recommended version for decent ESR measurement?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 27, 2016, 01:48:43 pm
The latest k and m firmware versions ;) The issue is only related to film caps about 180 - 220nF, IIRC.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lpc32 on November 27, 2016, 02:50:22 pm
You mean newer versions fix the clock speed dependency?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 27, 2016, 03:46:49 pm
There's no fix for that yet (m-firmware). Unless you need to measure the ESR of a 180 - 220nF cap, you don't have to worry about this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lpc32 on November 29, 2016, 12:13:51 am
Thanks.

By the way, what were the changes in "trendy" vs "classic"? Is it now continuing on a single line based on just "trendy"?
And why, actually, does Karl-Heinz work on a separate branch instead of merging back to your mainline?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2016, 01:08:07 pm
When I started to add support for graphic displays, I've renamed the old firmware to "classic" and the new one became "trendy". The classic edition supports ATmega 168/328 and 2x16 HD44780 compatible displays. For the graphic displays I had to add an abstraction layer, which was too much for an 168. So the trendy edition was 328 only at first (now it's 328, 324, 644 & 1284). Of course, it still supports HD44780 based displays, up to 4*20. Since all clones got a 328 meanwhile, I've dropped the parallel releases after a while. So  "trendy" is the active one. I was thinking about going back to the former naming (just m-firmware), but I don't know if it might confuse users or not.

Regarding the k-firmware, it's the other way around. The control logic and things like the abstraction layer for displays are quite different, and merging both branches into one would take a huge effort. Anyway, competition creates progress ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: lpc32 on November 29, 2016, 05:21:05 pm
I think it would be less confusing to remove the "trendy" suffix, and just note somewhere clearly that 1.xx is the last version that supports the 168. BTW, if it's abstracted in the newer versions, can't one conditionally compile with just the segmented display code?

Competition can drive progress, but also hinder it, especially with small dev groups. :)

Quote
Regarding the k-firmware, it's the other way around.
Oh, sorry. I mixed you up with M.F.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2016, 06:09:31 pm
What do other users think about dropping the "trendy" suffix?

BTW, if it's abstracted in the newer versions, can't one conditionally compile with just the segmented display code?

The code for driving HD44780 based displays is the smallest anyway, since it doesn't got the character bitmaps, just a few symbols. Adding an #ifdef orgy to allow to skip the display abstraction layer would make the code much more muddled in my opinion. And the abstraction layer also takes care about muli-line displays. Otherwise we would need a second #ifdef orgy for 4*20 displays. Too much trouble for saving about 500-700 bytes, IIRC.
Title: Re: $20 LCR ESR Transistor checker project
Post by: milamber on November 29, 2016, 08:00:57 pm
Then we should keep "#define LCD_RES  PD0". If LCD_RES is set to PD4, which isn't connected to the LCD module, the pin doesn't contol anything, besides creating some additional heat in the bottom resistor of the frequency counter's input voltage divider. So setting PD0 would increase the run time of the battery ;)

@madires:
The "Clones" file in ComponentTester-trendy-1.25m.tgz is still showing the wrong "white screen" PD4 setting instead of PD0 for LCD_RES.
Ran into the problem today with my AY-AT.
Could you please correct that in the next version?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2016, 08:10:05 pm
Of course, it's already fixed in the Clones file for 1.26m, which will be released when I've sorted out the compensation for the inductance measurement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lpc32 on November 30, 2016, 04:25:20 pm
Too much trouble for saving about 500-700 bytes, IIRC.
I meant the reverse, excluding the pixel-display code to allow supporting the 168. I'm not familiar with the code, so thought it would be something like excluding the pixel-display source file, and maybe ifdefing a few lines in a header file.

But anyway, I was just curious. I don't know if people still need 168 support.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 30, 2016, 04:51:05 pm
You compile the firmware for a specific display controller anyway. When you choose the HD44780, just the code for that controller will be included, and not any code for graphic LCDs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: boffin on November 30, 2016, 06:16:44 pm
I was actually considering modifying the firmware to add a 'serial' option for the display, so that you just send it a command (test component) and it comes back with the results.  Part of a test system I was thinking about.

Anyone done anything similar?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 30, 2016, 07:05:18 pm
Not yet, but for the ATmega 324/644/1284 based circuit the RXD0 and TXD0 pins are reserved for a serial interface. Currently there's only a software UART in the k-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RoDiSK on November 30, 2016, 07:18:29 pm
Hi, I bought this ESR meter (http://rodi.sk/misc/avr-component-tester/),
-what is his mark ? M328 ? GM328 ?
-somewhere it is possible to download the latest software for 16MHz crystal ?

I bought it in aliexpress from store "All sea Store" and not everything is OK...
a) unpopulated SMD components :( (Seller has the pictures already mounted SMD)
b) 1x missing resistor 33 k? (1x more resistor 3.3 k?)

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 30, 2016, 08:18:46 pm
that's the "AY-AT" colour tft kit.

it has nothing to do with a GM328 which is completely different and does not use a colour display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: milamber on November 30, 2016, 08:27:28 pm
@RoDiSK: It's the AY-AT Version with 8 MHz oscillator.

The k-Version from Karl-Heinz (SVN 684) can be found here.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg997651/#msg997651 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg997651/#msg997651)
stj just provided (SVN 685):
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1081866/#msg1081866 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1081866/#msg1081866)

Just compiled the Markus Trendy Version 1.25 for you attached as 8MHz Version.
(And as 16MHz version, if you exchange the oscillator.)
Settings for TL866 Programmer are included.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RoDiSK on November 30, 2016, 10:30:01 pm
@stj & @milamber - thanks
oscilator is in socket and 16MHz is on way
Title: Re: $20 LCR ESR Transistor checker project
Post by: egil on December 02, 2016, 10:37:45 am
For anyone venturing into any of the ready made PCBs from China, I have made case designs suitable for 3D printing for several variants. If you do not have a 3D printer yourself, you can order 3D prints for various places. My designs are:

GM328A: https://www.thingiverse.com/thing:1920077 (https://www.thingiverse.com/thing:1920077)
M12864: http://www.thingiverse.com/thing:1580922 (http://www.thingiverse.com/thing:1580922)
LCR-T4: http://www.thingiverse.com/thing:797733 (http://www.thingiverse.com/thing:797733)
LCR-T3: http://www.thingiverse.com/thing:694790 (http://www.thingiverse.com/thing:694790)
Alphanumeric: http://www.thingiverse.com/thing:641003 (http://www.thingiverse.com/thing:641003)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 03, 2016, 04:31:48 pm
Back to the inductance measurement. It's a can of worms. I've checked several testers with different PCBs and MCU clocks and found some common pattern of deviations. The compensation logic for the high current check is done, I hope. For the low current check I've added a simple compensation, which still needs more investigation (I have to order some inductors above 10mH). The problem with the inductance measurement is that several things got an impact on the results, and some of them are tester specific. I've choosen compensation offsets which work fine with most of my testers. So please don't be surprised if your tester might need some tweaking.

For the new 1.26m we got following changes:
- Added compensation for inductance measurement (more work required).
- Added Spanish texts. Translation provided by pepe10000@EEVblog.
- Changed FrequencyCounter() to support also ATmega 324/644/1284.
- Fixed problem in inductance measurement logic. Reported by indman@EEVblog.
- Fixed error in voltage reference handling for ATmega 324/644/1284.
- Improved detection of turning velocity of rotary encoder to cope with different values of pulses per step or detent.
- Added hardware SPI to all drivers for SPI based displays.
Title: Re: $20 LCR ESR Transistor checker project
Post by: milamber on December 05, 2016, 07:42:00 pm
For the new 1.26m we got following changes:
- Added hardware SPI to all drivers for SPI based displays.
Compiled 1.26m for AY-AT 16MHz and the AY-AT settings from Clones.
@madires: BITBANG SPI takes 5 seconds for one screen refresh (about 10 times slower than in 1.25m). Can you confirm that with your displays?

Just trying to get Hardware SPI running. Compiled it with:
#define LCD_SPI_HARDWARE        /* bit-bang SPI interface */
#define LCD_SCL          PB5            /* port pin used for SCL & SPI HARDWARE @ SCK */
#define LCD_SDA         PB3            /* port pin used for SDA & SPI HARDWARE @ MOSI */
instead of
//#define LCD_SPI_BITBANG                 /* bit-bang SPI interface */
//#define LCD_SCL          PD2            /* port pin used for SCL & SPI BITBANG */
//#define LCD_SDA          PD3            /* port pin used for SDA & SPI BITBANG */
and rewired the display to PD2&PD3 pins to PB5&PB3 with the 328er@16MHz. Screen still white - maybe mixed something up with the wiring.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 05, 2016, 08:32:02 pm
I'll check the ST7735, but hardware SPI won't run with an ATmega 328 because of the circuit's pin assignment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 06, 2016, 02:15:27 pm
Hi, madires! Thanks for really lot of work in the new version!  :-+ Inductance measurement perfectly works, I didn't do any settings in addition.
Title: resistors vs. kit contents
Post by: ja421 on December 06, 2016, 04:44:04 pm
I received a new kit yesterday to replace an old one I destroyed (rolled over it with a chair).
I picked up one similar to this (http://www.ebay.com/itm/272234590655?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT).
The kit was missing a few parts, it contained only 1 capacitor for the crystal, but it was missing the crystal, and sent 2 33K resistors, but the board is marked 3K3.
Question is: Which should be right? Kit contents, or board silk screen?.  Sadly, no schematic from vendor, no response either (not really expected it).
Since the crystal is missing, would it be worth putting a 16mhz crystal in, instead of 8mhz? (I understand I'd need to load a different firmware.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 06, 2016, 05:10:15 pm
Compiled 1.26m for AY-AT 16MHz and the AY-AT settings from Clones.
@madires: BITBANG SPI takes 5 seconds for one screen refresh (about 10 times slower than in 1.25m). Can you confirm that with your displays?

I've checked the ST7735 and haven't seen any difference in display performance between 1.25m and 1.26m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 06, 2016, 07:31:01 pm
I didn't note any difference in the display speed of operation 1.25 and 1.26 too  :)
Title: $20 LCR ESR Transistor checker project
Post by: edy on December 06, 2016, 08:01:26 pm
I bought one of these types of devices a few years ago and it helped me test a number of components and fix a TV Power supply. I am not sure how reliable or accurate they are but it was cheap. Here is the video on it. Looks like it fits some of those ready made case designs above. Mine didn't come in a case... Which would have been nice  to house the 9V battery and also protection.

https://youtu.be/ZUq6QDuSbfY (https://youtu.be/ZUq6QDuSbfY)


Sent from my iPhone using Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: chick0n on December 06, 2016, 09:52:48 pm
Hi

I bought this one:

http://www.banggood.com/DIY-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-Meter-p-1056454.html?rmmds=myorder (http://www.banggood.com/DIY-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-Meter-p-1056454.html?rmmds=myorder)

It uses JLX12864G-086 Display Module, with UC1701x Controller.

What firmware Configuration can I use?

thanks!
Title: Re: resistors vs. kit contents
Post by: stj on December 06, 2016, 10:06:11 pm
I received a new kit yesterday to replace an old one I destroyed (rolled over it with a chair).
I picked up one similar to this (http://www.ebay.com/itm/272234590655?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT).
The kit was missing a few parts, it contained only 1 capacitor for the crystal, but it was missing the crystal, and sent 2 33K resistors, but the board is marked 3K3.
Question is: Which should be right? Kit contents, or board silk screen?.  Sadly, no schematic from vendor, no response either (not really expected it).
Since the crystal is missing, would it be worth putting a 16mhz crystal in, instead of 8mhz? (I understand I'd need to load a different firmware.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: coromonadalix on December 07, 2016, 02:25:45 am
would be nice to have a compilation for Example : an 128x64  graphic lcd based on ks0108 ???   they are cheap for 10$ on Ebay

bigger is better  loll 

I have a old mega 2560 sitting duck in my drawer ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 07, 2016, 11:35:58 am
It uses JLX12864G-086 Display Module, with UC1701x Controller.

What firmware Configuration can I use?

At first glance it seems to be compatible with the ST7565. So please try ST7565.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 07, 2016, 12:08:51 pm
would be nice to have a compilation for Example : an 128x64  graphic lcd based on ks0108 ???   they are cheap for 10$ on Ebay

bigger is better  loll 

I have a old mega 2560 sitting duck in my drawer ...

The k-firmware supports the ATmega 2560, but not KS0108 based LCDs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on December 07, 2016, 09:23:20 pm
I installed the 1.25m firmware on a 16 Mhz AY-AT board.  Seems to work well, but I haven't done much with inductors.

One thing that I noticed is that blue text on the black background is VERY difficult to read (particularly when the sign-on / bye splash screens flash by in under a second)  Perhaps a more contrasty color would a better choice.  People had a similar issue in Lady Heather and I changed the blue to a lighter, more violet palette... it's still not all that good, but I needed to display 14 more-or-less distinct colors and a shade of blue was needed.   White or yellow shows up quite well against black.

Also, any plans to implement the FET Rds-on and body diode Vf measurements that 1.12k does?
Title: Re: $20 LCR ESR Transistor checker project
Post by: chick0n on December 07, 2016, 11:08:56 pm
It uses JLX12864G-086 Display Module, with UC1701x Controller.

What firmware Configuration can I use?

At first glance it seems to be compatible with the ST7565. So please try ST7565.

"mega328_T3_T4_st7565" works, with slight Modifications.

But I cant get it calibrated.

When I short the 3 testports, it shows "self test?" then measures ohm between testports, then it shows "not calibrated!" again. No differences when I press the Button.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 07, 2016, 11:20:57 pm
when it says "self test?" press the button.
Title: Re: $20 LCR ESR Transistor checker project
Post by: chick0n on December 07, 2016, 11:41:16 pm
when it says "self test?" press the button.

It measures ohms, if I press the Button or not. then shows not calibrated
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 07, 2016, 11:56:53 pm
no, your not fast enough.
you short the 3 pins together, then turn it on.
it says "self test?" and you press the button quickly to go into calibration mode.

the only other time i have seen it constantly say it's not calibrated is when the eeprom was not programmed properly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 08, 2016, 07:58:34 am
Hi, madires! :)
Whether it is possible to make in your firmware the same mode of the continuous measurements, how at Karl-Heinz?
That is, that the display wasn't cleared every time in case of new measurement, and only the tested value changed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 08, 2016, 12:34:25 pm
One thing that I noticed is that blue text on the black background is VERY difficult to read (particularly when the sign-on / bye splash screens flash by in under a second)  Perhaps a more contrasty color would a better choice.  People had a similar issue in Lady Heather and I changed the blue to a lighter, more violet palette... it's still not all that good, but I needed to display 14 more-or-less distinct colors and a shade of blue was needed.   White or yellow shows up quite well against black.

You can change the color (COLOR_TITLE) in color.h easily, but I'll try some colors with more contrast.

Also, any plans to implement the FET Rds-on and body diode Vf measurements that 1.12k does?

I'll put it on the to-do list. With R_DS_on we have to be careful because the tester is limited to 5V, i.e. max. V_GS is 5V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 08, 2016, 12:49:55 pm
Whether it is possible to make in your firmware the same mode of the continuous measurements, how at Karl-Heinz?
That is, that the display wasn't cleared every time in case of new measurement, and only the tested value changed?

Do you mean the "resistor meter" and "capacitor meter" menu functions?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 08, 2016, 01:25:32 pm
Yes, madires, i mean LCR measurement mode - the capacitor, inductor, resistance. ;)
At Karl - Heinz it is most conveniently organized.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on December 08, 2016, 02:34:43 pm
With R_DS_on we have to be careful because the tester is limited to 5V, i.e. max. V_GS is 5V.

At the low channel currents used by the tester,  5V for Vgs will give a pretty good idea of the Rds of most FETs (even those that are spec'd for a 10+ volt Vgs... certainly good enough for sorting through devices.   Testing some high threshold devices with 1.12K was showing an Rds of 100 milliohms.   Checking them with 15 volts on the gate, an HP3458A showed a channel resistance of 95 milliohms.

Being able to check devices at sub-threshold gate voltage can be useful.  I built a 20,000 capacitive discharge amp spot welder with 18 IRFP2907's in parallel.  I bought 100 fets and matched them by comparing their channel resistance at Vgs=3V  I wanted the devices to turn on at the same time and chose those that were closest.  At 3V the 100 devices had Rds values from 30 to 3000 milliohms.

Title: Re: $20 LCR ESR Transistor checker project
Post by: chick0n on December 08, 2016, 06:09:18 pm
no, your not fast enough.
you short the 3 pins together, then turn it on.
it says "self test?" and you press the button quickly to go into calibration mode.

the only other time i have seen it constantly say it's not calibrated is when the eeprom was not programmed properly.

hmm...avrdude verifies the eeprom ok
Title: Re: $20 LCR ESR Transistor checker project
Post by: chick0n on December 09, 2016, 03:10:24 pm
no, your not fast enough.
you short the 3 pins together, then turn it on.
it says "self test?" and you press the button quickly to go into calibration mode.

the only other time i have seen it constantly say it's not calibrated is when the eeprom was not programmed properly.

Ok... I think I figured it out.

I think the Button of my Tester, is somehow connected to PC6 (Reset Pin) instead of PD7.


"Pauli" here, had the same Problem:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/250/

He Connected his Button to PC6, and wondered why his Tester didn`t react to Pressed Button after "Selftest?" question.

Can I Correct this in the Source-Code, or do I have to make Hardware-Modification?

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: chick0n on December 09, 2016, 05:34:45 pm
no, your not fast enough.
you short the 3 pins together, then turn it on.
it says "self test?" and you press the button quickly to go into calibration mode.

the only other time i have seen it constantly say it's not calibrated is when the eeprom was not programmed properly.

Ok... I think I figured it out.

I think the Button of my Tester, is somehow connected to PC6 (Reset Pin) instead of PD7.


"Pauli" here, had the same Problem:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/250/

He Connected his Button to PC6, and wondered why his Tester didn`t react to Pressed Button after "Selftest?" question.

Can I Correct this in the Source-Code, or do I have to make Hardware-Modification?

Thanks!

I measured it, and the button is connected to PD0. (What the heck??)

So I soldered a bridge from PD0 to PD7. Now everything Works.....

Better DONT buy this clone:
http://www.banggood.com/DIY-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-Meter-p-1056454.html (http://www.banggood.com/DIY-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-Meter-p-1056454.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on December 10, 2016, 04:14:51 pm
One thing that I noticed is that blue text on the black background is VERY difficult to read (particularly when the sign-on / bye splash screens flash by in under a second)  Perhaps a more contrasty color would a better choice.  People had a similar issue in Lady Heather and I changed the blue to a lighter, more violet palette... it's still not all that good, but I needed to display 14 more-or-less distinct colors and a shade of blue was needed.   White or yellow shows up quite well against black.

You can change the color (COLOR_TITLE) in color.h easily, but I'll try some colors with more contrast.

Also, any plans to implement the FET Rds-on and body diode Vf measurements that 1.12k does?

I'll put it on the to-do list. With R_DS_on we have to be careful because the tester is limited to 5V, i.e. max. V_GS is 5V.

I finally got the 1.26 tar.gz file to decompress properly and compile for my 16 MHz AY-AT (using WinAVR).  I changed the title color to white and it looks good.   I also edited the display routine in user.c to show capacitance in uF...  I'm a luddite geezer and hate those new fangled nanofarad thingies...  pF and uF only for me.

My configuration uses 98.1% of the flash capacity...  I suspect something got to go (probably the remote control tool) if the Rds and Vf measurements are added. 

I have a 10 watt "TV-B-GONE" flashlight that sequentially sends the OFF codes for most televisions.  There are a lot of codes that the tester could not identify... not surprising... there are a LOT of remote control formats out there.


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 10, 2016, 05:09:41 pm
My configuration uses 98.1% of the flash capacity...  I suspect something got to go (probably the remote control tool) if the Rds and Vf measurements are added. 

I assume that both won't increase the firmware much, because Vf is already measured by the diode check, and R_DS_on is just a simple calculation (measured values are already available also). No biggy ;)

I have a 10 watt "TV-B-GONE" flashlight that sequentially sends the OFF codes for most televisions.  There are a lot of codes that the tester could not identify... not surprising... there are a LOT of remote control formats out there.

Yup, tons of IR protocols. If you're interested in IR codes, there are a few web sites with lists or databases of IR codes. I've included the most common ones from the remote controls I've borrowed from my family and a few neighbours. IIRC, about the half uses the NEC protocol, expecially unknown brands.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 10, 2016, 07:43:23 pm
How low can they go?  <$5.77 shipped?

https://www.aliexpress.com/item/LCR-T4-Transistor-Tester-12846-LCD-M328-Tester-Newest-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP/32721881253.html (https://www.aliexpress.com/item/LCR-T4-Transistor-Tester-12846-LCD-M328-Tester-Newest-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP/32721881253.html)

Need a case?  $2.70

https://www.aliexpress.com/item/Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-LCR-T4-Transistor-Tester-LCD-Display-Mega328-Transistors-Diodes/32765181716.html? (https://www.aliexpress.com/item/Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-LCR-T4-Transistor-Tester-LCD-Display-Mega328-Transistors-Diodes/32765181716.html?)
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlxDroidDev on December 11, 2016, 03:36:45 am
I have a 10 watt "TV-B-GONE" flashlight that sequentially sends the OFF codes for most televisions.  There are a lot of codes that the tester could not identify... not surprising... there are a LOT of remote control formats out there.

Writing an Arduino sketch and schematics that receives IR codes and prints them on a LCD display isn't complicated at all. Let me me know if you want something like that.

Actually, the code that receives the IR data and prints it on a serial terminal is already as a sample in the IRremote library (http://github.com/shirriff/Arduino-IRremote) (by Ken Shirriff). It is the IRrecvDump sample and can be built on a breadboard.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on December 11, 2016, 03:53:58 am
I've done a lot of IR decoding / sending before.   The 10 watt TV-B-GONE flashlight will turn off TV's from a LONG way away.  I had it in my jacket pocket when I was in a hobby store that had a couple dozen TVs running... I switched it on, still in my pocket,  they all went off within 30 seconds.  >:D

I was just using it to play with the tester IR decoder function.   I think it sends around 50 different OFF codes in sequence.  The IR function is cute, but I'm not sure how useful it is.  If I don't run out of space, it will stay. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: deriterkeeg on December 11, 2016, 11:13:22 am
How low can they go?  <$5.77 shipped?

https://www.aliexpress.com/item/LCR-T4-Transistor-Tester-12846-LCD-M328-Tester-Newest-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP/32721881253.html (https://www.aliexpress.com/item/LCR-T4-Transistor-Tester-12846-LCD-M328-Tester-Newest-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP/32721881253.html)

Hi,
Thanks for the links but .... please read again bullet #5:
"5. 1602 lcd display uses LCD (12864 LCD with backlight) "
The pictures are exhibiting a graphic LCD ! !.

By the way, Thanks to all the contributors, especially to Madires.
regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 12, 2016, 05:37:42 am
Something tells me that whoever posted that doesn't really know what it means. Correct me if I'm wrong, but I'd say it's either 1602 or 12864, not both. The picture is probably (probably!) a better indication of what's actually for sale.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 12, 2016, 05:09:00 pm
How low can they go?  <$5.77 shipped?

https://www.aliexpress.com/item/LCR-T4-Transistor-Tester-12846-LCD-M328-Tester-Newest-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP/32721881253.html (https://www.aliexpress.com/item/LCR-T4-Transistor-Tester-12846-LCD-M328-Tester-Newest-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP/32721881253.html)

Hi,
Thanks for the links but .... please read again bullet #5:
"5. 1602 lcd display uses LCD (12864 LCD with backlight) "
The pictures are exhibiting a graphic LCD ! !.

By the way, Thanks to all the contributors, especially to Madires.
regards

This is one of the original $20 "LCR T4" versions and probably half of the people here purchased one of these over the years.  This is what I have done with mine, including replacing the 8MHz crystal with a 16MHz one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 13, 2016, 02:10:57 am
what is the relay for?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 13, 2016, 02:56:32 am
The relay DPDT is normally closed and it shorts all input, when you turn on the tester the relay opens.  Basically the relay protect all inputs if you insert a charged capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 13, 2016, 03:39:38 am
ah right,
i thought it was for the "small parallel cap" for inductance testing.
but couldnt see a film cap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 13, 2016, 06:40:28 am
That's an interesting idea. But how would it be controlled? Some of the controller's pins are already pulling double duty...
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 13, 2016, 07:19:58 am
i spoke by email about this with mr Heinz a while back, he thought re-using the pin that is connected to the voltage reference was one way, if i remember right.

i already have a fet driven relay mod on mine, but i switch the fet manually at the moment.
btw, if you put a relay near the socket you should use a metal-screened "telecom" type or it may effect the inductor with it's field.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 13, 2016, 11:54:12 am
The optional relay for discharging caps is driven by PC4 (ATmega 328), which is also the input for the optional external 2.5V reference. k and m-firmware support this (m: HW_DISCHARGE_RELAY in config.h). You'll find the old circuit plus an improved one in Karl-Heinz's documentation (section 2.2.1).
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 13, 2016, 12:19:29 pm
we arent talking about the relay for discharge,
we are talking about the parallel cap for small inductor testing.

i doubt the relay would be much good against a fully charged low impedence cap anyway - it would probably have it's contacts burned.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 13, 2016, 01:34:31 pm
Ok, so the idea is to use PC4 (ATmega328) to drive a relay for a parallel cap instead of the discharging relay. At the moment the driver function for the discharging relay is integrated in the k-firmware (no switchable option). That would need to become an option while adding another one for the parallel cap. The 324/664/1284 dev board has a relay plus cap already on board (driven by PC2).

PS: I'm no friend of the discharging relay also.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 13, 2016, 06:26:19 pm
Thanks to the forum I already have the rotary encoder installed and running on one of my LCR-T4.

I have made some photos in case someone is interested in making the modification that can serve as a guide.

Also included are photos of the 9V battery charger with constant current made with an LM317 and a still unfinished sub-coupler to measure optocouplers.

In order to operate in the correct direction the rotary encoder with the soldered cables in this way the following lines must be changed in the "config_328.h":

#define ENCODER_A        PD3
#define ENCODER_B        PD1

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: deriterkeeg on December 15, 2016, 12:27:42 pm
Something tells me that whoever posted that doesn't really know what it means. Correct me if I'm wrong, but I'd say it's either 1602 or 12864, not both. The picture is probably (probably!) a better indication of what's actually for sale.
Ok, buy it and tell us about your experience.
This kind of description is common. Who knows about the subject asks a question, others fall into the trap!
cheaper isn't the best.
regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 16, 2016, 03:35:55 pm
While checking my to-do list I've stumbled across CLDs/CRDs (current limiting diodes / current regulater diodes). A quick search shows that they are availiable up to about 5mA (high current ones up to 23mA), which can be handled by the transistor tester. Common types seem to be 1N5285 up to 1N5314. If you got some CLDs and like to support this project, I'd appreciate a few samples ;)

The next version of the m-firmware will be named just "Component Tester" without any hint about the edition to make things less complicated. So far I've added R_DS and Vf (body diode) for MOSFETs, and support for fixed IR receiver modules. Also I've moved the component symbol from the bottom to the right to have more lines for data (data on the left, symbol on the right).
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on December 16, 2016, 03:54:32 pm
While checking my to-do list I've stumbled across CLDs/CRDs (current limiting diodes / current regulater diodes).

Don't forget my favorite...  the tunnel diode  >:D  I actually use the beasties (plus very common in old Tek scopes).   They have the interesting property of exhibiting negative resistance above their current threshold point.   I don't think anybody makes them anymore.   I have to buy them from Russia. 

I think I have a local source of some CRDs.  I'll check today.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 16, 2016, 09:11:52 pm
Something tells me that whoever posted that doesn't really know what it means. Correct me if I'm wrong, but I'd say it's either 1602 or 12864, not both. The picture is probably (probably!) a better indication of what's actually for sale.
Ok, buy it and tell us about your experience.
This kind of description is common. Who knows about the subject asks a question, others fall into the trap!
cheaper isn't the best.
regards

Looks like you took it the wrong way. I was referring to the person who posted the listing. That description is not just common, it looks like a "standard" copy/pasted one that's used all over the place. Useless. The images are supposedly the only clue of what you're buying. If you think that that particular seller is selling something else, that's even worse.

While checking my to-do list I've stumbled across CLDs/CRDs (current limiting diodes / current regulater diodes). A quick search shows that they are availiable up to about 5mA (high current ones up to 23mA), which can be handled by the transistor tester. Common types seem to be 1N5285 up to 1N5314. If you got some CLDs and like to support this project, I'd appreciate a few samples ;)

The next version of the m-firmware will be named just "Component Tester" without any hint about the edition to make things less complicated. So far I've added R_DS and Vf (body diode) for MOSFETs, and support for fixed IR receiver modules. Also I've moved the component symbol from the bottom to the right to have more lines for data (data on the left, symbol on the right).

Wouldn't those diodes mess up at least some of the measurements if permanently installed? Is it even possible to compensate for a semiconductor at the input of a semiconductor tester?

As an aside, would it be a lot of work to print out everything after an underscore a couple of pixels lower than the rest and then to reset position at the null byte? I haven't looked at the code in a long time...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 16, 2016, 10:10:46 pm
Wouldn't those diodes mess up at least some of the measurements if permanently installed? Is it even possible to compensate for a semiconductor at the input of a semiconductor tester?

The CLDs won't be installed, they are going to be checked ;)

As an aside, would it be a lot of work to print out everything after an underscore a couple of pixels lower than the rest and then to reset position at the null byte? I haven't looked at the code in a long time...

Yes. Either we would have to add a low-height font to support displays with a fixed page size, or we would need a screen buffer for displays without a read function.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on December 16, 2016, 11:05:40 pm
While checking my to-do list I've stumbled across CLDs/CRDs (current limiting diodes / current regulater diodes).

I think I have a local source of some CRDs.  I'll check today.

I bought some 330 uA and 390 uA CRD's today.   K firmware does not see them.   1.26M firmware says they are diodes with If = 308 and 389 uA.   What does the number in (..) after the Vf mean?

I suspect the way to test for CRDs is to try driving them with different voltages and if the current stays (reasonably) constant that they are CRD's.

Madires, if you want to try them, PM me your address and I'll send them out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: deriterkeeg on December 17, 2016, 11:23:59 am
Looks like you took it the wrong way. I was referring to the person who posted the listing. That description is not just common, it looks like a "standard" copy/pasted one that's used all over the place. Useless. The images are supposedly the only clue of what you're buying. If you think that that particular seller is selling something else, that's even worse.
Apologies, I misled the sense of your former reply.
Being an intensive eBayer, as soon as a picture doesn't fit the description, I suspect the listing! 
I never bought on aliexpress yet. Considering good bargains, is it equivalent to eBay ?
Regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 17, 2016, 01:48:17 pm
I bought some 330 uA and 390 uA CRD's today.   K firmware does not see them.   1.26M firmware says they are diodes with If = 308 and 389 uA.   What does the number in (..) after the Vf mean?

The number in parentheses is Vf for the low current measurement (470k resistor, around 10µA). It's only displayed when the voltage is below 250mV, which mostly happens for Ge or Schottky diodes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 17, 2016, 04:59:51 pm
Hello, I installed the EC11 rotary encoder (20 steps 20 pulses according to distributor) in two units of the LCR-T4 those yellow color (Chinese clones) and with the firmware m everything works perfect, right, left, slow spin, normal spin, Quick spin etc.

But with the k firmware, it works fine but only with slow turns, if you turn the encoder at half speed or fast the screen fails, text lines jump, vertical streaks go out or it goes blank even though the tester keeps running.

Example:

(http://es.zimagez.com/miniature/img20161217173040.jpg) (http://es.zimagez.com/zimage/img20161217173040.php)

I have compiled the latest version available (Trunk 699) with the options:

CFLAGS += -DWITH_ROTARY_SWITCH=2
CFLAGS += -DCHANGE_ROTARY_DIRECTION

I have also put the Pull-UP resistances recommended in the manual and quartz crystal at 16MHZ (photos in post # 3006 a little higher).

It happens to me in the two units exactly the same, is that normal?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 17, 2016, 05:20:03 pm
That's strange! I've forwarded your report to Karl-Heinz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ja421 on December 17, 2016, 05:23:39 pm
do you really mean this:
Code: [Select]
CFLAGS += -DWITH_ROTARY_SWITCH=2( "=2" )?
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 17, 2016, 05:29:58 pm
do you really mean this:
Code: [Select]
CFLAGS += -DWITH_ROTARY_SWITCH=2( "=2" )?

Yes, =2, according to the make:

Quote
# If your encoder has the same count of pulses at any switch as indexed positions (detent) for every turn,
# you should set the WITH_ROTARY_SWITCH to 2 or 3.

I tested with 2 and with 3, and the result is the same, the LCD fails if the encoder is rotated to medium or fast speed.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kubi48 on December 17, 2016, 09:11:56 pm
The rotary encoder extension can only work correctly with the default pin setting, if the communication ports for the display are swiched to low (0V) and high level (5V). Because this board use a display controller, which don't tolerate 5V signals, the ATmega outputs are swiched to 0V only (Makefile option LCD_SPI_OPEN_COL). The high level is generated with pull-up resistors. I see only one workaround to use other port signals for the rotary encoder, which are not used for the display controller communication. Probably the PD5 signal is not used, but PD4 is used as LCD-Reset. The LCD-Reset signal is rised to high level at the program start. Probably this signal can also be generated with a RC combination. So you can use PD4 and PD5 for the rotary encoder.
Of course you must set the Makefile options ROTARY_1_PIN and ROTARY_2_PIN to change the software.
If you remove the Makefile option LCD_SPI_OPEN_COL, the rotary encoder will probably work correctly, but the supply voltage of the LCD controller can increase to a illegal value.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 17, 2016, 09:38:21 pm
The rotary encoder extension can only work correctly with the default pin setting, if the communication ports for the display are swiched to low (0V) and high level (5V). Because this board use a display controller, which don't tolerate 5V signals, the ATmega outputs are swiched to 0V only (Makefile option LCD_SPI_OPEN_COL). The high level is generated with pull-up resistors. I see only one workaround to use other port signals for the rotary encoder, which are not used for the display controller communication. Probably the PD5 signal is not used, but PD4 is used as LCD-Reset. The LCD-Reset signal is rised to high level at the program start. Probably this signal can also be generated with a RC combination. So you can use PD4 and PD5 for the rotary encoder.
Of course you must set the Makefile options ROTARY_1_PIN and ROTARY_2_PIN to change the software.
If you remove the Makefile option LCD_SPI_OPEN_COL, the rotary encoder will probably work correctly, but the supply voltage of the LCD controller can increase to a illegal value.

I have the power supply of the LCD controlled by an AMS1117 3.3, so I think it would not be a big problem.

The strange thing is that with firmware m works perfectly.

If you wish tomorrow I can do the test to remove the LCD_SPI_OPEN_COL to see what happens.

Thanks and best regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 17, 2016, 10:23:00 pm
Hello, I installed the EC11 rotary encoder (20 steps 20 pulses according to distributor) in two units of the LCR-T4 those yellow color (Chinese clones) and with the firmware m everything works perfect, right, left, slow spin, normal spin, Quick spin etc.

But with the k firmware, it works fine but only with slow turns, if you turn the encoder at half speed or fast the screen fails, text lines jump, vertical streaks go out or it goes blank even though the tester keeps running.

Example:

(http://es.zimagez.com/miniature/img20161217173040.jpg) (http://es.zimagez.com/zimage/img20161217173040.php)

I have compiled the latest version available (Trunk 699) with the options:

CFLAGS += -DWITH_ROTARY_SWITCH=2
CFLAGS += -DCHANGE_ROTARY_DIRECTION

I have also put the Pull-UP resistances recommended in the manual and quartz crystal at 16MHZ (photos in post # 3006 a little higher).

It happens to me in the two units exactly the same, is that normal?

Unfortunately it is "normal" with this particular tester.  I have exactly the same problem and I am also using exactly the same LCR-T4 version tester.  I reported this problem back in April on Page 78 staring with post 1926, a lot of advice but no solution.  After recently changing my crystal to 16MHz it looks like it is behaving a little better but still if I rotate the encoder anyway faster than about 1 click per second the display will get scrambled or most of the time the display will become blank and the only way to recover is to the reset the processor.  I gave up trying fixing it so I installed a reset switch so I can reset the darn thing without opening my box every time it happens.

On post 2997 you can see a picture of my tester.  This picture is before I installed the reset switch.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 18, 2016, 11:20:35 am
I have compiled the latest available version k (702) with the option:

#CFLAGS + = -DLCD_SPI_OPEN_COL

And everything works perfect, so far nothing has broken and measurements go well.
The rotary encoder can be rotated at any speed without affecting the screen.

In these days I will be attentive to the operation in case something strange happens to report it.

Many thanks to all for the help and greetings
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on December 18, 2016, 04:24:59 pm
Hi everybody,

Does someone have the latest K and M versions for AY-AT tester.
Don't have knowledge of compiling etc.
ehh, shame, and to lazy to learn,
maybe when I have lots of time.

Thanks anyway.
Pukker
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 18, 2016, 05:44:05 pm
K here:
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 18, 2016, 06:09:33 pm
I have compiled the latest available version k (702) with the option:

#CFLAGS + = -DLCD_SPI_OPEN_COL

And everything works perfect, so far nothing has broken and measurements go well.
The rotary encoder can be rotated at any speed without affecting the screen.

In these days I will be attentive to the operation in case something strange happens to report it.

Many thanks to all for the help and greetings

Hi, is this https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/) the version that you used which fixed the problem?  If it is not then please provide a link to it.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 18, 2016, 07:18:03 pm
Exactly:

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/)

I remind you that I have installed an AMS1117 3.3 for working voltage of LCD, resistors PULL-UP (attached image) and a crystal of 16MHZ.

I include image of another one that is in the process of assembly and improvements (even without putting the rotary encoder).

Good luck and I hope that works for you as well as me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: edavid on December 18, 2016, 08:30:32 pm
While checking my to-do list I've stumbled across CLDs/CRDs (current limiting diodes / current regulater diodes). A quick search shows that they are availiable up to about 5mA (high current ones up to 23mA), which can be handled by the transistor tester. Common types seem to be 1N5285 up to 1N5314. If you got some CLDs and like to support this project, I'd appreciate a few samples ;)

They are just JFETs with the gate and source shorted, so you can use your JFET collection to test your code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 18, 2016, 09:15:16 pm
Exactly:

[url]https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/[/url] ([url]https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/[/url])

I remind you that I have installed an AMS1117 3.3 for working voltage of LCD, resistors PULL-UP (attached image) and a crystal of 16MHZ.

I include image of another one that is in the process of assembly and improvements (even without putting the rotary encoder):

([url]http://es.zimagez.com/miniature/img20161218195913.jpg[/url]) ([url]http://es.zimagez.com/zimage/img20161218195913.php[/url])

Good luck and I hope that works for you as well as me.


Please clarify, your problem with the encoder rotation speed was fixed after you updated the firmware to version 702 or after you added the 3.3v regulator for the display with the external pull ups. 

At the time when I tried to fix this problem, I tried to lower the voltage to the LCD display by adding a third diode in series to the original two diodes (without any external pull up resistors) and that didn't make much of a difference.  My last firmware I used was whatever was the latest version about a month ago and I am not sure if that is the difference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 18, 2016, 09:31:41 pm
Exactly:

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/)

I remind you that I have installed an AMS1117 3.3 for working voltage of LCD, resistors PULL-UP (attached image) and a crystal of 16MHZ.

I include image of another one that is in the process of assembly and improvements (even without putting the rotary encoder):

(http://es.zimagez.com/miniature/img20161218195913.jpg) (http://es.zimagez.com/zimage/img20161218195913.php)

Good luck and I hope that works for you as well as me.

Please clarify, your problem with the encoder rotation speed was fixed after you updated the firmware to version 702 or after you added the 3.3v regulator for the display with the external pull ups. 

At the time when I tried to fix this problem, I tried to lower the voltage to the LCD display by adding a third diode in series to the original two diodes (without any external pull up resistors) and that didn't make much of a difference.  My last firmware I used was whatever was the latest version about a month ago and I am not sure if that is the difference.

The speed of rotation of the encoder was fixed when I changed the line:

#CFLAGS + = -DLCD_SPI_OPEN_COL

The regulator of 3.3v and the resistances were already set before, I just mentioned it as additional data in case it was useful.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 18, 2016, 09:48:21 pm
Sorry, I don't remember what was the default, you compiled with:

#CFLAGS + = -DLCD_SPI_OPEN_COL
or
CFLAGS + = -DLCD_SPI_OPEN_COL
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 18, 2016, 09:56:09 pm
Sorry, I don't remember what was the default, you compiled with:

#CFLAGS + = -DLCD_SPI_OPEN_COL
or
CFLAGS + = -DLCD_SPI_OPEN_COL

Original:

CFLAGS + = -DLCD_SPI_OPEN_COL

Fixed Encoder:

#CFLAGS + = -DLCD_SPI_OPEN_COL
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 18, 2016, 10:05:34 pm
What about the pull ups for the encoder?  They should be also pulled up to the 3.3v regulator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 18, 2016, 10:11:38 pm
What about the pull ups for the encoder?  They should be also pulled up to the 3.3v regulator.

No, I have the encoder PULL-UP connected to 5v, look at the photos from post #3006 for more information.

(http://es.zimagez.com/miniature/img20161213165707.jpg) (http://es.zimagez.com/zimage/img20161213165707.php)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 18, 2016, 11:15:23 pm
If you have the encoder pulled up to 5v, I think you are defeating the purpose of the 3.3v regulator.  I would just have to verify that these encoders are specified to function at 3.3v.

The entire problem stems from the fact that the processor is powered by 5v driving an LCD that is designed to operate at 3.3v.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 19, 2016, 06:36:44 am
If you have the encoder pulled up to 5v, I think you are defeating the purpose of the 3.3v regulator.  I would just have to verify that these encoders are specified to function at 3.3v.

The entire problem stems from the fact that the processor is powered by 5v driving an LCD that is designed to operate at 3.3v.

I have connected the encoder to 5v because this explains the manual in section 2.2.5.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=155911;image)

The regulator is only installed because in the forum it was advised to set it so that the LCD worked at the voltage specified by the manufacturer.

Certainly all the problems derive from using an LCD that works at 3.3v, I have thought of replacing it with another one but the expense and the fudge that has to be done does not compensate, better buy a new one with all the options available like the GM328 for example.

(http://www.kvintal.com.ua/UserFiles/Image/foto/Izmeritel/GM328TFT_2.jpg)

But as the electronica is my great hobby I prefer to modify the ones that I have to offer me the maximum benefits possible and to maximize them.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 19, 2016, 08:10:56 am
Very well Pepe, if Electronics is only a hobby for you then you are doing a great job.  For me Electronics in not only a great hobby but also my profession.

As far as the Karl's original manual, if you interface a processor that is powered with 5v to an LCD that is also powered by 5v then of course you would want to power the encoder with 5v.  I did a quick search and I could not find a detail spec for these encoders so I am not sure if they can function properly at 3.3v which could be a problem.

In our case, to eliminate the problems we were experiencing you would want all outputs from the processor going to the LCD to be open collectors and all pull ups including the encoder and the LCD power from a separate 3.3V regulator as you did.  When I get some more time I will fix it for good.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 19, 2016, 08:40:01 pm
It has also been my profession for more than 25 years, but now with the crisis I have been unemployed for 6 years, so now it is more a hobby, and having free time I can learn many more things.

When I solve it, I hope you will comment on the results, so it works very well for me at the moment.

I have only noticed a small fault and is that when you turn the encoder super-fast the tester restarts.

But under normal circumstances the encoder is never turned so fast.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 19, 2016, 10:37:25 pm
Sorry to hear that you have been unemployed for so long, here the economy is not that good either.  Hopefully with our new president it will improve significantly.   I am an EE with over 30 years of design experience and now finally retired.

It would be interesting to know if you can try powering the encoder with 3.3v instead of 5v and hopefully that will fix your last problem.  Simply move the white wire that goes to the input of your 3.3v regulator to the output of the regulator.  I still didn't find a detail spec of these encoders so I am not sure if they will function at 3.3v but you have nothing to loose.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 20, 2016, 06:45:54 am
the encoder is a physical switch, it will function at any low voltage
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 20, 2016, 07:11:32 pm
Sorry, that isn't true.   The encoder is a digital switch that produces 2 outputs that are 90 degree out of phase and the phase shift depends on the direction of rotation.  Like any other digital circuitry its Vcc has a certain spec.  As I said,  I could not find a detail spec to figure out if it will function properly at 3.3v.  If it uses TTL logic then it needs 5V, it it uses CMOS logic then 3.3v will be fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on December 20, 2016, 07:24:11 pm
These rotary encoders are used as digital switches.
But there is no digital logic inside of them. See also:
http://henrysbench.capnfatz.com/henrys-bench/arduino-sensors-and-input/keyes-ky-040-arduino-rotary-encoder-user-manual/#Keyes_Rotary_Encoder_Schematic (http://henrysbench.capnfatz.com/henrys-bench/arduino-sensors-and-input/keyes-ky-040-arduino-rotary-encoder-user-manual/#Keyes_Rotary_Encoder_Schematic)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 20, 2016, 07:51:58 pm
Please see http://www.robotroom.com/Counter5.html (http://www.robotroom.com/Counter5.html) for some nice tear-down pictures of a simple rotary encoder ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 20, 2016, 08:52:39 pm
Well, I stand corrected, you guys are right!  I just had to take one of these apart now, I guess this is NOT what I used to work with.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 20, 2016, 09:05:08 pm
At the moment I'm working on an alternative PWM generator especially for a rotary encoder and a display with more than 2 text lines. With a button press you can switch between frequency and ratio, while the rotary encoder changes the value. That way you don't have to select the frequency from a fixed list first. It works similar to the squarewave generator. BTW, would anyone interested in a dedicated servo test providing the proper PWM signal?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on December 21, 2016, 12:17:11 am
+1 for the servo tester, if present I'll add a separate/external power souce to provide the proper current/voltage to the servo under test.
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on December 21, 2016, 12:21:51 am
BTW, would anyone interested in a dedicated servo test providing the proper PWM signal?

I don't work with servos, but sounds like a useful tool. Use the rotary encoder to change pulse width and, hence, position.
Title: Re: $20 LCR ESR Transistor checker project
Post by: edavid on December 21, 2016, 05:31:51 am
BTW, would anyone interested in a dedicated servo test providing the proper PWM signal?

I don't see much need for it, since everyone with servos to test has probably bought one of these: http://www.ebay.com/itm/1pcs-multi-Servo-tester-3CH-ECS-speed-controler-Power-CHANNELS-CCPM-meter-/172214381958 (http://www.ebay.com/itm/1pcs-multi-Servo-tester-3CH-ECS-speed-controler-Power-CHANNELS-CCPM-meter-/172214381958)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on December 21, 2016, 10:01:08 am
It seems that they are selling the 'AY-AT color kit' now with extra functions added in the firmware.
https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32732193545.html?spm=2114.13010308.0.0.duTKII (https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32732193545.html?spm=2114.13010308.0.0.duTKII)

Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on December 21, 2016, 03:42:14 pm
At the moment I'm working on an alternative PWM generator especially for a rotary encoder and a display with more than 2 text lines. With a button press you can switch between frequency and ratio, while the rotary encoder changes the value. That way you don't have to select the frequency from a fixed list first. It works similar to the squarewave generator.

For brainstorming sake, it shall be good if there is an emulator for various type of PWM chips out there.  This can be helpful in troubleshoot switch mode power supply.   The supply works in a closed loop.  If the loop is broken, find the area that is broken is non-trivial.  As it is, it may not be possible for this checker.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 21, 2016, 04:10:45 pm
It would be interesting to know if you can try powering the encoder with 3.3v instead of 5v and hopefully that will fix your last problem.  Simply move the white wire that goes to the input of your 3.3v regulator to the output of the regulator.

Hi, I connected the rotary encoder to 3.3v to get out of doubt and the behavior has been the same.

When you rotate super-fast the meter will restart.

As I said before is not a serious problem since it is not necessary to rotate the encoder so fast.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 21, 2016, 06:09:03 pm
maybe it's glitching the power rail.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ja421 on December 21, 2016, 06:30:07 pm
It seems that they are selling the 'AY-AT color kit' now with extra functions added in the firmware.
I ordered this one, it arrived w/ incorrect & missing parts; as well as a blank atmega328p and no download for firmware...  (I ended up using M firmware & updated to 16mhz)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 22, 2016, 04:12:41 am
It would be interesting to know if you can try powering the encoder with 3.3v instead of 5v and hopefully that will fix your last problem.  Simply move the white wire that goes to the input of your 3.3v regulator to the output of the regulator.

Hi, I connected the rotary encoder to 3.3v to get out of doubt and the behavior has been the same.

When you rotate super-fast the meter will restart.

As I said before is not a serious problem since it is not necessary to rotate the encoder so fast.

A greeting.
Hi again,  I looked carefully at your board wiring and I see that you have external pool up resistors on pin 32 (PD2) and pin 2 (PD4) both tied to the 5v supply. 

I don't understand why you have the poll ups tied to the 5v and not to your 3.3v supply.  If you are going to have these external pull up tied to your 5v, you might as well use the processor's internal pull ups and use the CFLAGS + = -DLCD_SPI_OPEN_COL command.  The purpose of this command I think is so you can disable the internal pull ups and provide external pull ups exactly us as you did but not tied them to the 5v. 

In your case, since you powered the LCD display from your 3.3v regulator, you would want all inputs to the LCD display including the encoder swing to 3.3v only and not to 5v which is the real reason for all the problems that we are experiencing.

You did mentioned that once you disabled the internal pull ups with the # CFLAGS + = -DLCD_SPI_OPEN_COL command, that fixed most of your problems.  My only explanation for that is that probably the processor wasn't able to sink the current from both pull up the external and internal and that is why you had to disable the internal pulls ups.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on December 22, 2016, 10:51:45 am
It seems that they are selling the 'AY-AT color kit' now with extra functions added in the firmware.
I ordered this one, it arrived w/ incorrect & missing parts; as well as a blank atmega328p and no download for firmware...  (I ended up using M firmware & updated to 16mhz)
That seems to happen with some sellers, I had it too, but the seller sent me a programmed chip for free. As it should be.

>>> In my post I was referring to those new built-in firmware menu options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 22, 2016, 12:29:56 pm
I don't understand why you have the poll ups tied to the 5v and not to your 3.3v supply.

They are at 5v because so advises Karl-Heinz here:

https://www.mikrocontroller.net/topic/248078?page=single#4541666 (https://www.mikrocontroller.net/topic/248078?page=single#4541666)

Quote
You did mentioned that once you disabled the internal pull ups with the # CFLAGS + = -DLCD_SPI_OPEN_COL command, that fixed most of your problems.

If you have solved the spin problems, but that command does not disable PULL-UP, I think it only controls communications with the LCD.

To disable PULL-UP, use the command "CFLAGS + = -DPULLUP_DISABLE" and it is necessary to change it if you do not have these resistors as the screen would be blank using the firmware located at "https://www.mikrocontroller.net / Svnbrowser / transistortester / Software / trunk / mega328_T3_T4_st7565 / (https://www.mikrocontroller.net / Svnbrowser / transistortester / Software / trunk / mega328_T3_T4_st7565 /)".

A greeting.
Title: New User
Post by: madcat on December 23, 2016, 12:20:30 pm
Hi all,
i just bought this "AY-AT" type tester, still have no chance to assembly it yet.
gladly, it came with those SMD parts nicely soldered in place already.

what i read here, there's some users reported that they received wrong pieces of resistors (between 3.3k and 33k).
here what i received are : 2pcs of 3.3k  and 1pc of 33k (confirmed with DMM).
based at PCB labels, they supposed to be correct, don't they?


btw, i have listed all of the components i received, if there's anyone interested, i will post it here. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on December 23, 2016, 01:55:28 pm
See the long description of the 'AY-AT color kit' tester here:
https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32732193545.html?spm=2114.13010308.0.0.duTKII (https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32732193545.html?spm=2114.13010308.0.0.duTKII)

The components are listed there as well.
and see the attachments of:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)]$20-lcr-esr-transistor-checker-project/msg1007286/#msg1007286
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on December 23, 2016, 04:27:52 pm
thank you very much Willem52, those links are very informative.
i think the "transistor tester assembly instruction" pdf needs a little correction in the components table.
where 3.3k resistors marked R12, R7, but in number of component column listed as "1".  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on December 23, 2016, 05:47:13 pm
Well, the information now available is more than we can expect from most of the Chinese vendors 😎
Title: Re: $20 LCR ESR Transistor checker project
Post by: edavid on December 23, 2016, 05:55:24 pm
Here's a scan I made of the AY-AT PCB... in the image, the bottom side is flipped, which I find convenient when probing from the top side.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 23, 2016, 06:59:01 pm
Hi, I need some help.  I added the required hardware for testing Zener diodes on a T3-T4 tester.  What exactly do I have to change in the Make file to have the firmware work?  I am using firmware ver. 698.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 23, 2016, 07:49:51 pm
WITH_VEXT
EXT_NUMERATOR
EXT_DENOMINATOR
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 23, 2016, 08:53:08 pm
Thanks, I skipped the EXT_NUMERATOR and EXT_DENOMINATOR, it was driving me nuts. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 24, 2016, 12:23:14 am
WITH_VEXT
EXT_NUMERATOR
EXT_DENOMINATOR
I am sorry, still cannot get it to test zeners.  The voltage across the zener is the correct voltage, PC3 is 1/10 the zener voltage and the display is blinking unknown ...  Everything else is working fine, any ideas?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 24, 2016, 06:37:35 am
And it doesn't show the zener voltage while you're holding down the button?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on December 24, 2016, 09:48:27 am
Here's a scan I made of the AY-AT PCB... in the image, the bottom side is flipped, which I find convenient when probing from the top side.
thanks for the pic edavid. nice and clear.  :-+

what is still bugging my head is : why did some users who bought this AY-AT type tester complained when they received 2pcs of 3.3k and 1pc of 33k, said that it should be vice versa in numbers.
from the PCB label and PDFs given by Willem52 above, looks like AY-AT does need 2pcs of 3.3k and 1pc of 33k.

here's one of them :
Hi, I bought this ESR meter (http://rodi.sk/misc/avr-component-tester/),
-what is his mark ? M328 ? GM328 ?
-somewhere it is possible to download the latest software for 16MHz crystal ?

I bought it in aliexpress from store "All sea Store" and not everything is OK...
a) unpopulated SMD components :( (Seller has the pictures already mounted SMD)
b) 1x missing resistor 33 k? (1x more resistor 3.3 k?)

thanks

am i missing something here?  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on December 24, 2016, 01:44:23 pm
I checked my made pictures also and I see only 2 x 3K3 and 1 x 33K resistors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 24, 2016, 06:10:26 pm
And it doesn't show the zener voltage while you're holding down the button?
OK, I got it.  I didn't know I had to hold the button down for so long (>5 sec.).  It is kind of awkward, first the display blinks a few times Unknown..., then it goes into the encoder Selection mode, then it restarts again and only then it display the (Vext) Zener voltage. 

You have to remember, the original test current is very low so the displayed Zener voltage would be much lower than the typical Zener rating.  I have tripled the original maximum test current and it helped a little, however the actual Zener current would still be much lower because it depend on the tested Zener voltage and its power ratings.   Overall, I don't think it is worth the effort of adding the additional Zener testing circuitry.   An adjustable bench power supply with a current limiting resistor would give you better results.  I will post some pictures of my tester once I clean it up a little.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on December 25, 2016, 05:38:39 am
Here is my final tester, not much room left in the box.  If anyone is interested here is a quick tour.  The main tester is a T3-T4 board with a an Arduino rotary encoder, 16 MHz crystal and an input protection relay all powered by a 18650 Lithium battery.

Top left side is the lithium battery charger and protection circuit.  Bottom left side is the main 5V output step up converter (3.7v to 5v) which replaces the original 5v linear regulator.  Right side is the Zener testing 28V output step up converter (3.7v to 28v identical to the 5V output converter). 

Adding the 3rd converter caused initially some ringing on the 3.7v input which was the reason the display blinked a couple of times on turn on.  Adding an LC filter fixed the problem.  For a small plastic box with 3 separate PWM converters, everything is behaving quit nicely. 

The only problem I am still experiencing is inherent to this particular tester design as its processor powered by 5v drives directly the display controller which is designed to operate on 3.3v.  If I turn the encoder quickly, the display will sometime lockup.  The easiest way to recover from that was to add a reset switch which you can see at the bottom center of the board with a pin hole in the case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stolz on December 25, 2016, 02:43:49 pm
I am a newbie and would appreciate any help. I built an AY-AT transistor tester kit that I got on ebay (TOMTOPTECH).  This has firmware 1.12K and  8 MHz crystal. The unit does work and it completes the calibration sequence, but I am getting very inaccurate measurements and there is no repeatability when retesting the same component. Most resistors read incorrectly, however a 270 ohm and a 1.5K ohm did read correctly. Capacitors seem to always read a much lower value than expected. (This is actually my second attempt with this kit. The first one exhibited the same issues that I have described so the seller exchanged it for the one I just completed and unfortunately it also has the same problems.) I am a reasonably experienced kit builder so I don't think there is a problem with mis-located components or improper soldering. One thing that seems unusual was that during the calibration routine, the Ri-Hi value comes up as a smaller number than the Ri-Lo value, although I admit I have no idea what this means.

I had also previously built a  transistor tester from Banggood (ST7565 128x64) and that one has worked extremely well so I am using that as a reference point to judge the AY-AT which seems to be off by a mile. Can anybody suggest what the problem could be with the AY-AT and how to go about fixing it? 

If this involves changing the firmware, I did have to do that on my Banggood tester and I was successful (despite my lack of knowledge) based on the excellent instructions provided by generous contributors to this forum.  Thanks in advance for any help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 25, 2016, 04:11:47 pm
make sure you cleaned off the flux,
and dont trust the quality of the test socket.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 27, 2016, 02:10:54 am
I have an EZM MK-328 in the case. It looks like this one: http://i.ebayimg.com/images/g/ZOUAAOSwcBhWZP31/s-l500.jpg (http://i.ebayimg.com/images/g/ZOUAAOSwcBhWZP31/s-l500.jpg)

It originally had 1.12k firmware. I just tried to flash the latest K firmware and am having trouble. I have successfully flashed firmware on two different, older testers, so I know the procedure.

Using a USBASP, I flashed the firmware HEX file. I got a verification error. Now, when I try to re-flash or erase,  I get the following:

avrdude: error: program enable: target doesn't answer. 1
avrdude: initialization failed, rc=-1
         Double check connections and try again, or use -F to override
         this check.

When I use the -F option, I get this:

avrdude: error: program enable: target doesn't answer. 1
avrdude: initialization failed, rc=-1
avrdude: AVR device initialized and ready to accept instructions
avrdude: Device signature = 0x4c0000
avrdude: Expected signature for ATmega328P is 1E 95 0F

As I said, I have flashed other testers before with no trouble. What happened this time? How can I fix it?

Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 27, 2016, 03:04:45 am
Ok, I got it working again. Some research made me thing that it was a timing issue with the USBASP.

I'm not sure, but when I flashed the earlier component tester boards, the USBASP probably had the original Chinese firmware (which used to give a clock error). I later flashed the USBASP with the official firmware, which didn't give the clock error.

Just now, I flashed the USBASP with this firmware: https://github.com/bperrybap/usbasp/tree/1.06-alpha

I am now able to communicate with the EZM tester again. I am flashing it now. I hope I picked the correct firmware.

EDIT: I tried two different firmwares. Does anyone know which K firmware is correct?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Smelter on December 27, 2016, 01:02:52 pm
I bought a MK-328 in the middle of this year (to measure the coil of a relay) to further my project of a narrow boat monitor, that I was drawn into creating an Instructable for, as they were giving away LinkIt ONE cards. I'm now at the stage of making a working tachograph. I bought the Rigol DS1054Z (haven't we all) after Dave's rave review, and was looking for a frequency reference source to prove my work in progress design. Yesterday I switched on my MK-328 and held the switch down longer than needed and found the menu table listing a frequency generator!
24hrs later, after trawling this forum, and locating the manual for the 1.12k version of the software, I have a working test bed to make progress with without having to buy a separate signal generator.
Thanks to everyone here on the forum and the open source community for helping along this hobbyist.
Best wishes and a happy new year to all.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 27, 2016, 08:15:19 pm
I have tried four different firmwares, including two that purport to be MK-328 specific versions. All of them program and verify. When pressing the on/test button, all I get is the backlight on the LCD. From what I read here, this indicates that no firmware is programmed. However, like I said, I did get a 100% verify on the EEP and HEX files. I did also program the fuses with the recommended settings.

Any ideas? I'd like to get this tester working again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 28, 2016, 12:08:14 am
i dont know what pcb is in that unit, but try the GM328x firmware i post sometimes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 28, 2016, 03:45:01 am
Thanks for posting, but your firmware has the rotary encoder enabled. This model has no encoder.

Here is a link that shows the circuit board in this thing and a firmware that I tried.

No mater which firmware I flash, it acts like it isn't programmed. When flashing with USBASP at 3.3V, it wouldn't verify. Flashing at 5V does verify. I'm thinking that perhaps the uC chip is flakey.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 28, 2016, 11:33:18 am
my builds dont need the rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 28, 2016, 02:36:29 pm
I have tried four different firmwares, including two that purport to be MK-328 specific versions. All of them program and verify. When pressing the on/test button, all I get is the backlight on the LCD. From what I read here, this indicates that no firmware is programmed. However, like I said, I did get a 100% verify on the EEP and HEX files. I did also program the fuses with the recommended settings.

Any ideas? I'd like to get this tester working again.

Does the tester stay powered on (LED and/or display backlight lit) for a few seconds after pressing the button?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 28, 2016, 04:54:27 pm
No, the backlight only stays lit while the button is pressed.

It looks like I forgot the link in my previous post: https://yadi.sk/d/yW8xa5NJgUo5z/Mk-328/
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 28, 2016, 05:09:12 pm
Then it might be an erased or bad MCU. The first thing the firmware does is setting PD6 high to keep the tester powered on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jbnl on December 28, 2016, 06:55:36 pm
Goodday,

I have this banggood tester M12864 and the processor is broken. I have found out that it is the ST7565 display so i downloaded the software from https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565/) and programmed it into a new processor.
The problem is that with the Galep III programmer i use i only can open a Hex file and i don't know what to do with the eep file.

When i program the processor and put it back and push the rotaty it turns on again and the display light up. but no text, it looks like the contrast is not setup right maybe because i did not programmed the eep file.
Now is my question the hex file from the svn browser contain that the complete file with the eep file, if now how can i program that with the galep III ?
I see something happens now on display but the contrast is max/low so not readable. How can help me with this ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 28, 2016, 07:23:59 pm
The eep file needs to be written into the MCU's EEPROM and it contains a lot of text, tables and settings, like the contrast for the LCD.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 28, 2016, 08:01:42 pm
the eep file is HEX format.
just rename it to eeprom.hex or something.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jbnl on December 28, 2016, 08:19:22 pm
Thanks, then i will find out in the galep software how i can put the eep at the right place. Thanks for the info !!
I will let you know if it works, i will try tomorrow.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on December 29, 2016, 12:39:45 am
For the Banggood M12864 I always used this firmware:

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)

Regarding the eep file, can you plese post a screenshot of the software you are using to program the Atmega328p after you selected the device to be programmed?
Are you sure that there isen't a tab or a sub-menù where you can select/program the eeprom content of the MCU?

The programmer should be able to program the flash memory of the MCU and the internal eeprom at the same time. You should find also the menu/tab to set the proper fuses

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: jbnl on December 29, 2016, 06:26:47 am
I have managed to program the mpu, i opened first the hex file and later on the eep file in a new section and copy and past the data on the main field on the right adress for the eeprom.
Now is it working again but very slow, but this was a other hex i found.
So now i will try the version from the trunk mentioned above.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jbnl on December 29, 2016, 06:46:10 am
I have tryed the mega328_st7565_kit file and it is working but the unit is very slow.
The x-tal is 8 Mhz.
Any idea's ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 29, 2016, 11:12:10 am
Possibly the fuse settings, i.e. the 1:8 clock divider (the MCU is running at 1MHz).
Title: Re: $20 LCR ESR Transistor checker project
Post by: jbnl on December 29, 2016, 11:29:30 am
Aha oke and what are the correct fuse settings ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 29, 2016, 11:59:18 am
For an 8MHz crystal it's:
- lfuse f7
- hfuse d9
- efuse fc
Title: Re: $20 LCR ESR Transistor checker project
Post by: jbnl on December 29, 2016, 12:31:48 pm
Super Super thanks for all the help, it works again !!!
Thanks all for all the help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 29, 2016, 12:35:07 pm
For an 8MHz crystal it's:
- lfuse f7
- hfuse d9
- efuse fc

Hello, and the fuses for Mega328P with 16 MHz crystal?

A greeting
Title: Re: $20 LCR ESR Transistor checker project
Post by: milamber on December 29, 2016, 01:08:26 pm
Possibly the fuse settings, i.e. the 1:8 clock divider (the MCU is running at 1MHz).
Ich think so, too. When I first programmed 1.26m, I did the same by mistake...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 29, 2016, 01:11:05 pm
Hello, and the fuses for Mega328P with 16 MHz crystal?

... are the same, because the clock divider stays 1:1.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jbnl on December 29, 2016, 01:29:05 pm
Yes that was the problem, now it works.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on December 29, 2016, 03:11:58 pm
I have tried four different firmwares, including two that purport to be MK-328 specific versions. All of them program and verify. When pressing the on/test button, all I get is the backlight on the LCD. From what I read here, this indicates that no firmware is programmed. However, like I said, I did get a 100% verify on the EEP and HEX files. I did also program the fuses with the recommended settings.

Any ideas? I'd like to get this tester working again.
Why don't you just post what your fuse settings are?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on December 29, 2016, 09:08:13 pm
Fuse settings are what Madres just posted a bit ago.

I suspect the uC is flakey. I ordered a replacement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on December 29, 2016, 10:51:06 pm
If it's in a socket, the problem could also be purely mechanical, like a bent pin or bad solder joint.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mmagin on January 10, 2017, 03:00:37 am
So, I got one of these cheap on ebay ($10), without a case, but with a ZIF socket.  This is a prettycute knock-off, TFXTDOL:

Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 10, 2017, 03:37:36 am
TFXTDOL to you as well, brave Terran!

For those who may not know, 3M™ Textool™ is (most likely) what this was supposed to be an identical copy of.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on January 10, 2017, 07:30:44 am
Yeah, I saw TFXTDOL the other day on someone else's tester. Almost as good as the PIAOET and BOLEX watches I've seen. :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: softfoot on January 10, 2017, 01:12:01 pm
I have recently bought one of the M328 based testers (see attached pic) but wish to update the firmware.

The problem is that I cannot figure out what the LCD controller is - the display is 128x64 and the existing firmware
displays graphical device outlines.

Can anyone tell me which LCD controller is used ?? and/or suggest which schematic is used for it ??

TIA
Best regards,
Dave

UPDATE!! I guessed it was an ST7565 but when I tried the firmware pre-compiled for that it only worked partially (the display was scrambled) however the code in the GM328 directory worked - I suppose that makes sense given the name of the box is M328 ;-)

Anyway, all tweaked and tested - works very well given the price.

Dave
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on January 10, 2017, 01:27:59 pm
Hi,
First of all thanks to the Author for making such great tool and making it public.
Had alot of bumps in making the hardware and after that i messed up the fuses, so had to use high voltage programming.
I built the stripe board. Flashed the firmware but it will only work while the button is pressed.

Pictures of the build and the high voltage programmer for resetting the fuses are attached,
and here is video of the tester in action

https://youtu.be/lUo0CBGCzDQ

And yes i know, the solder job is bad, the components are all cheap Chinese ones.


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 10, 2017, 03:00:23 pm
I have recently bought one of the M328 based testers (see attached pic) but wish to update the firmware.

The problem is that I cannot figure out what the LCD controller is - the display is 128x64 and the existing firmware
displays graphical device outlines.

Can anyone tell me which LCD controller is used ?? and/or suggest which schematic is used for it ??

I'd guess it's a ST7565.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 10, 2017, 03:10:00 pm
Had alot of bumps in making the hardware and after that i messed up the fuses, so had to use high voltage programming.
I built the stripe board. Flashed the firmware but it will only work while the button is pressed.

Please see https://github.com/svn2github/transistortester/tree/master/Hardware/strip_grid for the strip grid board design. It seems that your board hasn't got all the components for the power section. I see just one TO92. Or have you modified the circuit for a fixed 5V supply?

Edit: I stand corrected, I see 3 TO92 ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on January 10, 2017, 03:38:36 pm
It has all components except the REF1 and R15 (R15 is replaced with R16 47K)

T3 was BC558C now replaced with A94 (transistor)

IC2 is 78L05

T1 and T2 are  (BC548) (could not find 547)

The LED never turns on, tried to short it and it was the same, will only work when button is pressed. The 78L05 gives correct 5V and so does PD6 when button pressed, but as soon as i let go of button it turns off.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 10, 2017, 04:00:55 pm
Mea culpa, missed the other two TO92s. Please check the power section again. The LED should turn on when the push button is pressed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on January 10, 2017, 06:58:53 pm
hmm, i am trying to figure it out,
could you please recheck the stripe board version, i think it has error on T3
the pinout of T3 on stripe board using Row Colum
B J is the collector
A I is the Base
B H is the Emitter

according to schematic Collector should have 9+ from battery, but there is no connection
R10 (33k) should be on Collector and Base , but on the stripe board its on Emitter and Base

getting more confused now xd
will try more in the morning. I maybe wrong cause i am no electronics expert.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on January 10, 2017, 07:25:01 pm
this will happen if you fit the led the wrong way around.
someone learned this the other week while building a kit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on January 11, 2017, 12:48:51 am
Clever repackaging?
http://www.banggood.com/LCR-TN-Multifunction-Tester-TC-V2_12k-TFT-Display-With-Electronic-Tweezers-p-1117485.html?rmmds=preorder (http://www.banggood.com/LCR-TN-Multifunction-Tester-TC-V2_12k-TFT-Display-With-Electronic-Tweezers-p-1117485.html?rmmds=preorder)
The tweezers look like made out of PCB
Zener testing to 30V
Rechargeable
IR
Is it worth $35 ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 11, 2017, 11:56:42 am
Nice! Transistortester Tweezers. It's the modified k-firmware "M-Tester".



Dear Transistortester Cloners and Sellers!

We don't mind if you produce and sell clones of the Transistortester. It provides an inexpensive great little tool for electronics enthusiasts and beginners, but PLEASE note the links to the project's webpage, source repo and documentation. You would add more value by giving users that information to be able to update the firmware and to understand all the features. If you do any modifications to the firmware, please send us a copy for the repo. And if you would send us your Transistortester clones, we would be able to keep the firmware as compatible as possible. Don't forget, this an OSHW project!

Best regards,
 Transistortester team

Project's webpage: https://www.mikrocontroller.net/articles/AVR_Transistortester (https://www.mikrocontroller.net/articles/AVR_Transistortester)
SVN repo: https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)
GIT repo: https://github.com/svn2github/transistortester (https://github.com/svn2github/transistortester)
English documentation: https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf)
German documentation: https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/german/ttester.pdf (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/german/ttester.pdf)
Russian documentation: https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/russian/ttester.pdf (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/russian/ttester.pdf)
German forum (English is also fine): https://www.mikrocontroller.net/topic/248078 (https://www.mikrocontroller.net/topic/248078)
English forum: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/ (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 11, 2017, 05:27:03 pm
Someone really ought to translate that into Chinese and post it all over their DIYer forums since most of the clones seem to be from there these days.

Haven't we seen a 1602 clone inside a pair of SMD tweezers earlier?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 11, 2017, 11:50:00 pm
I hope someone in here can help me.
I bought a lcr t4 China model, and tryed to flash the 1,12k version to it.
But all i have now when i push the botton is a screen with nothing other then light in it.
Tryed to set a diode in it, and it flash it when i click the botton.
So iam thinking iam missing something in the flashing here?? (btw iam all new to this avr.)
If someone coulde help me with building the files and getting them flashed the right way.
I might even have fucked up in something with the lfuse, hfuse or efuse.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2017, 11:42:22 am
Have you programmed the firmware from https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_T3_T4_st7565 ? Another common problem is the default contrast, i.e. it might have to be changed for your display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 12, 2017, 02:23:39 pm
Have you programmed the firmware from https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_T3_T4_st7565 ? Another common problem is the default contrast, i.e. it might have to be changed for your display.
Yea i did, where do i adjust the contrast?? I cant get the makefile to workm in the avrdude programmer program.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2017, 02:36:31 pm
The default contrast is set in the Makefile (VOLUME_VALUE). But you need avr-gcc and all supporting packages or some IDE (Atmel Studio for example) to compile the firmware. avrdude is the tool to program the firmware and to set the fuse bits.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 12, 2017, 02:38:24 pm
The default contrast is set in the Makefile (VOLUME_VALUE). But you need avr-gcc and all supporting packages or some IDE (Atmel Studio for example) to compile the firmware. avrdude is the tool to program the firmware and to set the fuse bits.
Any guides in this??
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 12, 2017, 03:06:55 pm
I got wimavr.
So what do i do from here ??
Any way you can help me with it ??
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2017, 03:17:06 pm
Somewhere in this thread there are some guides on using different IDEs. Sorry, I'm running a linux based tool chain.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 12, 2017, 03:32:33 pm
This is the 1 i got.
Are the display the st7565??
what are the 2 solder pads for under the screen??
Title: Re: $20 LCR ESR Transistor checker project
Post by: jleg on January 12, 2017, 04:46:37 pm
I got wimavr.
So what do i do from here ??
Any way you can help me with it ??

there's quite a nice manual, also containing WinAVR instructions:
https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 12, 2017, 05:23:43 pm
i keep getting this error in programmers notepad when i try to makefile.
avr-objcopy -O ihex -R .eeprom -R .fuse -R .lock -R .signature  TransistorTester.elf TransistorTester.hex
avr-objcopy -j .eeprom --set-section-flags=.eeprom="alloc,load" --change-section-lma .eeprom=0 --no-change-warnings -O ihex TransistorTester.elf TransistorTester.eep || exit 0
      0 [main] sh 1776 sync_with_child: child 6252(0x180) died before initialization with status code 0xC0000142
  45005 [main] sh 1776 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
make.exe: [TransistorTester.eep] Error 128 (ignored)
avr-objdump -h -S TransistorTester.elf > TransistorTester.lss
      0 [main] sh 5276 sync_with_child: child 6392(0x178) died before initialization with status code 0xC0000142
  35625 [main] sh 5276 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
make.exe: *** [TransistorTester.lss] Error 128
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 12, 2017, 05:34:09 pm
I got this version working just the screen is the wrong way.
can any make me the files from this info ???
For the version 1,12.
I cant seem to get programmers notepad to work proberly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on January 12, 2017, 06:03:20 pm
I got this version working just the screen is the wrong way.
can any make me the files from this info ???
For the version 1,12.
I cant seem to get programmers notepad to work proberly.

Try this to see if it works for you.

Mega328_T3_T4_st7565 v1.12 k (702), Xtal=8MHZ, Font=8x16, No Resistor Pull-Ups Installed, With Rotary Check.

(http://es.zimagez.com/miniature/captura545.jpg) (http://es.zimagez.com/zimage/captura545.php)

Unzip with WinRar.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 12, 2017, 06:18:22 pm
I got this version working just the screen is the wrong way.
can any make me the files from this info ???
For the version 1,12.
I cant seem to get programmers notepad to work proberly.

Try this to see if it works for you.

Mega328_T3_T4_st7565 v1.12 k (702), Xtal=8MHZ, Font=8x16, No Resistor Pull-Ups Installed, With Rotary Check.

(http://es.zimagez.com/miniature/captura545.jpg) (http://es.zimagez.com/zimage/captura545.php)

Unzip with WinRar.

A greeting.
display just light up for 1sec and nothing else., ty for the try.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 12, 2017, 06:24:20 pm
can you try to compile this for me ??
Code: [Select]
###############################################################################
# Makefile for the project TransistorTester
###############################################################################

## General Flags
PROJECT = TransistorTester
TARGET = $(PROJECT).elf
VPATH = ..:../bitmaps
CC = avr-gcc

CPP = avr-g++

CFLAGS = -Wall

# ********************** Änderbare Flags zur Configuration des Transistortesters
# ********************** config options for your Semiconductor tester
# Every changing of this Makefile will result in new compiling the whole
# programs, if you call make or make upload.

# Select your Part-No. for avrdude :
# atmega8  : m8
# atmega168: m168 or m168p
# atmega328: m328 or m328p
# atmega1280: m1280 // see config.h for different port setting
# atmega2560: m2560 // see config.h for different port setting
PARTNO = m328p

# The WITH_MENU option enables a dialog to choose some additional functions.
# Currently a frequency measurement at ATmega Pin PD4, a frequency generator at TP2 ,
# the external voltage measurement and C+ESR measurement can be selected. Of course you can also return to
# the normal transistor tester function and switch off the tester.
CFLAGS += -DWITH_MENU
#
# For ATmega328 the menu function "rotary encoder check" is only enabled with the WITH_ROTARY_CHECK option.
CFLAGS += -DWITH_ROTARY_CHECK

# With the menu item "Show data" the used icons and the font data are displayed for
# graphical displays after the presentation of calibration data.
# You can switch off the presentation of the icons and the font data by setting
# the option NO_ICONS_DEMO to save flash memory and display time.
#CFLAGS += -DNO_ICONS_DEMO

# The menu function can be easier controlled with a incremental encoder (rotary switch).
# Both switches of the rotary switch can be connected with 1 kOhm resistors to PD1 and PD3.
# The common contact of the two switches must be connected to GND.
# You must also connect both switch contacts with two 10 kOhm resistors to VCC (pull up).
# The best choise is a incremental encoder with Push Button. The button can be connected
# parallel to the start key of the Transistor Tester.
# A define of the WITH_ROTARY_SWITCH enable the support for this extension.
# If your encoder has the same count of pulses at any switch as indexed positions (detent) for every turn,
# you should set the WITH_ROTARY_SWITCH to 2 or 3.
# If your encoder has twice the count of indexed positions, you should set the WITH_ROTARY_COUNT to 1.
# For rotary encoder without indexed position or with an indexed position at every change of
# the state of any switches (four times the count of pulses) you can set the
# WITH_ROTARY_COUNT to 5 for getting the best resolution.
# You can also use two separate push-buttons for Up and Down instead ot the rotary encoder.
# You must set the WITH_ROTARY_SWITCH to 4 for the UP/DOWN push-buttons.
CFLAGS += -DWITH_ROTARY_SWITCH=2
# the option CHANGE_ROTARY_DIRECTION changes the rotary direction by swap of switches
#CFLAGS += -DCHANGE_ROTARY_DIRECTION
# The best solution for connecting the rotary switch is PD1 and PD3, because this setting can be used
# with character and ST7565 LCD. But the first draft has used PD2 instead of PD1.
# To return to the old setting, you can override the PD1 default setting with the following setting:
# CFLAGS += -DROTARY_2_PIN=PD2

# Select your language:
# Available languages are: LANG_BRASIL, LANG_CZECH, LANG_DUTCH, LANG_ENGLISH, LANG_GERMAN, LANG_HUNGARIAN, LANG_ITALIAN,
#                          LANG_LITHUANIAN, LANG_POLISH, LANG_RUSSIAN , LANG_SLOVAK, LANG_SLOVENE, LANG_SPANISH, LANG_UKRAINIAN
UI_LANGUAGE = LANG_ENGLISH

# The LCD_CYRILLIC option is necessary, if you have a display with cyrillic characterset.
# This lcd-display don't have a character for Ohm and for µ (micro).
# Russian language requires a LCD controller with russian characterset and option LCD_CYRILLIC!
#CFLAGS += -DLCD_CYRILLIC

# The LCD_DOGM option must be set for support of the DOG-M type of LCD modules with ST7036 controller.
# For this LCD type the contrast must be set with software command.
#CFLAGS += -DLCD_DOGM

# Can be used with a 4x20 character display for better using the additional space.
# Additional parameters, which are shown only short in row 2, will be shown in row 3 and 4 with this option.
CFLAGS += -DFOUR_LINE_LCD
#CFLAGS += -DLCD_LINE_LENGTH=20

# Some character display types have a different DD_RAM start adress for line 1.
# Usually the DD_RAM start address for line 1 is 0.
# You can specify a different start address with the option DD_RAM_OFFSET
#DD_RAM_OFFSET=128

# The PAGE_MODE activates a moving line cursor for menu function selection together with FOUR_LINE_LCD
# and WITH_ROTARY_SWITCH.
# Without the PAGE_MODE option, the line cursor is fixed to line 3 and the text moves.
#CFLAGS += -DPAGE_MODE


# The LCD_ST7565 option must be set to support a 128x64 LCD graphics display
# with ST7565 controller. It is controlled with a 1-bit interface (SPI or I2C)
# The normal ST7565 controller will be supported by setting the WITH_LCD_ST7565 to 1 or 7565.
# The special action for a simular SSD1306 controller can be activated by
# setting the WITH_LCD_ST7565 variable to 1306.
WITH_LCD_ST7565 = 1
#WITH_LCD_ST7565 = 1306

# Normally the ST7565 controller is connected with a SPI 4-wire interface, but
# you can enable a I2C interface with address 0x3c for the SSD1306 controller
# by setting the LCD_INTERFACE_MODE to 2.
# The SCL signal is available at PD5 (LCD-E, LCD-6), the SDA signal at PD2 (LCD-D6, LCD-13).
# A pull up resistor of about 4.7k is required for both signals to 3.3V.
# Please check, if your display module can also tolerate a 5V signal level.
# For the ST7920 controller you can select the serial interface by setting the LCD_INTERFACE_MODE to 5 .
# ST7920-RW <--> PD2 , ST7920-E <--> PD5 , ST7920-PSB <--> GND , ST7920-RS <--> VCC , ST7920-RST <--> VCC
# For the PDF8814 controller you can also select a 3 for the 3-line serial interface with RS (D/C) as first bit.
# The RS (data/command) signal at PD1 is used as chip enable SCE.
#CFLAGS += -DLCD_INTERFACE_MODE=2

# With the option LCD_SPI_OPEN_COL the data signals of the SPI interface are not switched to VCC.
# With option LCD_SPI_OPEN_COL the signals are switched to GND only, for high signals the pullup resistors
# of the ATmega are used. For the RESET signal a external pull-up resistor is required, if the
# option PULLUP_DISABLE is set. For the other signals the internal pullup resistors of the ATmega
# are temporary used, even if option PULLUP_DISABLE is set.
CFLAGS += -DLCD_SPI_OPEN_COL

# The I2C Address can be preset to a address of 0x3d instead of 0x3c by setting the constant LCD_I2C_ADDR.
#CFLAGS += -DLCD_I2C_ADDR=0x3d

# If LCD_ST7565 option is used: Set the resitor ratio for the internal
# voltage regulator. Supported value range: 0..7.
# Good values are e.g. 4 or 7. If unsure just have a try.
LCD_ST7565_RESISTOR_RATIO = 4

# If LCD_ST7565 option is set to 1: Flip the display's horizontal direction.
#CFLAGS += -DLCD_ST7565_H_FLIP=1
# With LCD_ST7565_H_OFFSET you can specify a horizontal pixel offset to the display window.
# The controller knows 132 horizontal pixel, the window shows only 128 pixel.
# OFFSET values can vary for the connected display type to 0, 2 or 4.
CFLAGS += -DLCD_ST7565_H_OFFSET=0
# If LCD_ST7565 option is set to 1: Flip the display's vertical direction
#CFLAGS += -DLCD_ST7565_V_FLIP=1
# The contrast value can be predefined with the constant VOLUME_VALUE
# for ST7565 controller the value can be between 0 and 63, for the SSD1306 0 to 255 can be selected.
CFLAGS += -DVOLUME_VALUE=48

# You can specify a Y start line (vertical address) for the display output with the option LCD_ST7565_Y_START.
# If your output start in the middle of the display, you can specify a Y_START of 32
#CFLAGS += -DLCD_ST7565_Y_START=32

# If option WITH_LCD_ST7565 is present one of the following fonts should be
# choosen. With a font width below 8 more than 16 characters can be shown in one display line.
#CFLAGS += -DFONT_5X8
#CFLAGS += -DFONT_6X8
#CFLAGS += -DFONT_8X8
#CFLAGS += -DFONT_7X12
#CFLAGS += -DFONT_8X12thin
#CFLAGS += -DFONT_8X14
#CFLAGS += -DFONT_8X15
CFLAGS += -DFONT_8X16
#CFLAGS += -DFONT_8X16thin

# There are also different 24x32 pixel icons for presentation of the transistor symbols available.
# you can select a special type with setting the ICON_TYPE.
# Currently you can select 1 or 3 for one of two thin layouts for the icons.
# You can also select two thick layouts for the icons by setting the ICON_TYPE to 2 or 0 (0=old style).
CFLAGS += -DICON_TYPE=3

# option BIG_TP makes the 123 for the test pins (beside the icon) bigger
CFLAGS += -DBIG_TP
# option INVERSE_TP inverse the 123 for the test pins (black on white)
# the option INVERSE_TP disable the option BIG_TP because a frame is required
CFLAGS += -DINVERSE_TP

# Option STRIP_GRID_BOARD selects different board-layout, do not set for standard board!
# The connection of LCD is totally different for both versions.
CFLAGS += -DSTRIP_GRID_BOARD

# The WITH_SELFTEST option enables selftest function (only for mega168 or mega328) including the calibration.
# Normally the mega168 uses selftest without T1 to T7 to enable both hFE measurements.
CFLAGS += -DWITH_SELFTEST
# You can enable the extended tests T1 to T7 for the atmega168 by selecting the  NO_COMMON_COLLECTOR_HFE  option.
# The T1 to T7 tests are usefull to find problems with your tester.
# You can also disable the extended tests T1 to T7 with the option NO_TEST_T1_T7 to accelerate the calibration
# for the atmega328 and atmega168.
#CFLAGS += -DNO_TEST_T1_T7

# FREQUENCY_50HZ enables a 50 Hz frequency generator for up to one minute at the end of selftests.
#CFLAGS += -DFREQUENCY_50HZ

#CFLAGS += -DNO_COMMON_COLLECTOR_HFE
#CFLAGS += -DNO_COMMON_EMITTER_HFE

# AUTO_CAL will enable the autocalibration of zero offset of capacity measurement and
# also the port output resistance values will be find out in SELFTEST section.
# With a external capacitor a additionally correction of reference voltage is figured out for
# low capacity measurement and also for the AUTOSCALE_ADC measurement.
# The AUTO_CAL option is only selectable for mega168 and mega328.
CFLAGS += -DAUTO_CAL

# The tester reports the uncalibrated state with a message after testing a part.
# Normally a long text is shown, which explains the steps of calibration.
# You can prevent the long explanation by setting the SHORT_UNCAL_MSG option.
# With this option set, only a hint of one line is shown.
#CFLAGS += -DSHORT_UNCAL_MSG

# You can extend the measurement feature by use of a sampling mode for the ADC converter
# to extend the resolution of capacity measurement to about 0.01pF.
# Setting the WITH_SamplinADC to 1 enables this feature for capacity values below 100pF.
WITH_SamplingADC = 1

# Option WITH_XTAL enables additional Xtal / Ceramic resonator tests.
# Option can be set only together with SamplingADC=1 and OP_MHZ=16
#CFLAGS += -DWITH_XTAL
# Option WITH_UJT enables additional tests for UJT (UniJunction Transistor)
#CFLAGS += -DWITH_UJT
# Option WITH_PUT enables additional tests for PUT (Programmable Unijunction Transistor)
#CFLAGS += -DWITH_PUT

# The WITH_AUTO_REF option enables reading of internal REF-voltage to get factors for the Capacity measuring.
CFLAGS += -DWITH_AUTO_REF
# REF_C_KORR corrects the reference Voltage for capacity measurement (<40uF) and has mV units.
# Greater values gives lower capacity results.
CFLAGS += -DREF_C_KORR=12
# REF_L_KORR corrects the reference Voltage for inductance measurement and has mV units.
CFLAGS += -DREF_L_KORR=40
# C_H_KORR defines a correction of 0.1% units for big capacitor measurement.
# Positive values will reduce measurement results.
CFLAGS += -DC_H_KORR=0


# The WITH_UART option enables the software UART  (TTL level output at Pin PC3, 26).
# If the option is deselected, PC3 can be used as external voltage input with a
# 10:1 resistor divider.
#CFLAGS += -DWITH_UART

# With option TQFP_ADC6 or/and TQFP_ADC7 you can use the additional pins of the TQFP or
# the QFN package for external analog input. You should install a 10:1 voltage dividers
# on the selected pin(s).
# If both pins are defined, both voltages are measured with the voltage measure function.
# But for zener diode measurement the ADC6 pin is used, if both pins are defined.
#CFLAGS += -DTQFP_ADC6

# For ATmega8/168/328 processor the option WITH_VEXT can only be set, if the PC3 pin
# is not used for serial output (WITH_UART option).
# For ATmega644/1284 processor the UART has a separate pin.  Therefore the external input
# at pin ADC3 can be enabled separate by setting the WITH_UART option.
#CFLAGS += -DWITH_VEXT

#
# If you want to measure Inductors with the resistance meter, you must specify
# the RMETER_WITH_L  option. The measurement cycle time slow down with this option
# for resistors below 2.1kOhm. Resistors below 10 Ohm are measured additionally
# with the ESR measurement methode, which takes also a longer time.
CFLAGS += -DRMETER_WITH_L

# The CAP_EMPTY_LEVEL  defines the empty voltage level for capacitors in mV.
# Choose a higher value, if your Tester reports "Cell!" by unloading capacitors.
CFLAGS += -DCAP_EMPTY_LEVEL=4

# The AUTOSCALE_ADC option enables the autoscale ADC (ADC use VCC and Bandgap Ref).
CFLAGS += -DAUTOSCALE_ADC
CFLAGS += -DREF_R_KORR=3

# The ESR_ZERO value define the zero value of ESR measurement (units = 0.01 Ohm).
#CFLAGS += -DESR_ZERO=29
CFLAGS += -DESR_ZERO=20

# NO_AREF_CAP tells your Software, that you have no Capacitor installed at pin AREF (21).
# This enables a shorter wait-time for AUTOSCALE_ADC function.
# A capacitor with 1nF can be used with the option NO_AREF_CAP set.
CFLAGS += -DNO_AREF_CAP

# The OP_MHZ option tells the software the Operating Frequency of your ATmega.
OP_MHZ = 8

# Restart from sleep mode will be delayed for 16384 clock tics with crystal mode.
# Operation with the internal RC-Generator or external clock will delay the restart by only 6 clock tics.
# You must specify this with "CFLAGS += -DRESTART_DELAY_TICS=6", if you don't use the crystal mode.
#CFLAGS += -DRESTART_DELAY_TICS=6

# The USE_EEPROM option specify where you wish to locate fix text and tables.
# If USE_EEPROM is unset, program memory (flash) is taken for fix text and tables.
#CFLAGS += -DUSE_EEPROM

# Setting EBC_STYPE will select the old style to present the order of Transistor connection (EBC=...).
# Omitting the option will select the 123=... style.  Every point is replaced by a character identifying
# type of connected transistor pin (B=Base, E=Emitter, C=Collector, G=Gate, S=Source, D=Drain).
# If you select EBC_STYLE=321 , the style will be 321=... , the inverted order to the 123=... style.
#CFLAGS += -DEBC_STYLE
#CFLAGS += -DEBC_STYLE=321

# Setting of NO_NANO avoids the use of n as prefix for Farad (nF), the mikro prefix is used instead (uF).
# CFLAGS += -DNO_NANO

# With graphical displays the layout of pins is usually shown in long style " Pin  1=E 2=B 3=C"
# With the NO_LONG_PINLAYOUT option the short style "Pin 123=EBC" is used
#CFLAGS += -DNO_LONG_PINLAYOUT

# The PULLUP_DISABLE option disable the pull-up Resistors of IO-Ports.
# To use this option a external pull-up Resistor (10k to 30k)
# from Pin 13 to VCC must be installed!
CFLAGS += -DPULLUP_DISABLE

# The ANZ_MESS option specifies, how often an ADC value is read and accumulated.
# Possible values of ANZ_MESS are 5 to 200 .
CFLAGS += -DANZ_MESS=25


# The POWER_OFF option enables the power off function, otherwise loop measurements infinitely
# until power is disconnected with a ON/OFF switch (CFLAGS += -DPOWER_OFF).
# If you have the tester without the power off transistors, you can deselect POWER_OFF .
# If you have NOT selected the POWER_OFF option with the transistors installed,
# you can stop measuring by holding the key several seconds after a result is
# displayed. After releasing the key, the tester will be shut off by timeout.
# Otherwise you can also specify, after how many measurements without found part
# the tester will shut down (CFLAGS += -DPOWER_OFF=5).
# The tester will also shut down with found part,
# but successfull measurements are allowed double of the specified number.
#  You can specify up to 255 empty measurements (CFLAGS += -DPOWER_OFF=255).
#CFLAGS += -DPOWER_OFF=5
CFLAGS += -DPOWER_OFF

# Option BAT_CHECK enables the Battery Voltage Check, otherwise the SW Version is displayed instead of Bat.
# BAT_CHECK should be set for battery powered tester version.
CFLAGS += -DBAT_CHECK

# The BAT_OUT option enables Battery Voltage Output on LCD (if BAT_CHECK is selected).
# If your 9V supply has a diode installed, use the BAT_OUT=600 form to specify the
# threshold voltage of your diode to adjust the output value.
# This threshold level is added to LCD-output and does not affect the voltage checking levels.
CFLAGS += -DBAT_OUT=150

# To adjust the warning-level and poor-level of battery check to the capability of a
# low drop voltage regulator, you can specify the Option BAT_POOR=5400 .
# The unit for this option value is 1mV , 5400 means a poor level of 5.4V.
# The warning level is 0.8V higher than the specified poor level (>5.3V).
# The warning level is 0.4V higher than the specified poor level (>2.9V, <=5.3V).
# The warning level is 0.2V higher than the specified poor level (>1.3V, <=2.9V).
# The warning level is 0.1V higher than the specified poor level (<=1.3V).
# Setting the poor level to low values is not recommended for rechargeable Batteries,
# because this increase the danger for deep discharge!!
CFLAGS += -DBAT_POOR=6400

# You can set a upper battery voltage limit in mV units for battery operation mode.
# The operation time of additional functions is limited with the battery operation mode.
# Above the voltage limit "DC_PWR" the tester changes the operation mode to the
# "DC_Pwr_Mode", where time limits of the additional functions are switched off.
# The "DC_Pwr_Mode" is also started, if the battery voltage is detected below 0.9V
# regardless to the state of the DC_PWR option.
# CFLAGS += -DDC_PWR=9500

# Voltage divider for battery voltage measurement  10k / 3.3k = 133/33
CFLAGS += -DBAT_NUMERATOR=133
CFLAGS += -DBAT_DENOMINATOR=33
# Voltage divider for the external zener voltage measurement 180k / 20k = 10/1
#CFLAGS += -DEXT_NUMERATOR=10
#CFLAGS += -DEXT_DENOMINATOR=1

# The sleep mode of the ATmega168 or ATmega328 is normally used by the software to save current.
# You can inhibit this with the option INHIBIT_SLEEP_MODE .
INHIBIT_SLEEP_MODE = 0


# Select your programmer type, speed and port, if you wish to use avrdude.
# setting for DIAMEX ALL_AVR, Atmel AVRISP-mkII
PROGRAMMER=avrispmkII
BitClock=1.0
PORT=usb
# setting for USBasp
#PROGRAMMER=usbasp
#BitClock=20
#PORT=usb
# setting for ARDUINO MEGA, requires bootloader
#PROGRAMMER=wiring
#PORT = /dev/ttyACM0
#BitClock=5.0
#AVRDUDE_BAUD = -b 115200 -D
# ********************** end of selectable options

include setup.mk

########### Compile only Assembler source available
lcd_hw_4_bit.o: lcd_hw_4_bit.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

wait1000ms.o: wait1000ms.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

swuart.o: swuart.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

########### Compile  Assembler source only, is time critical
GetESR.o: GetESR.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

########### Compile C or Assembler , Assembler saves more than 400 bytes flash
GetRLmultip.o: GetRLmultip.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

UfAusgabe.o: UfAusgabe.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

RvalOut.o: RvalOut.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

PinLayout.o: PinLayout.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

RefVoltage.o: RefVoltage.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

i2lcd.o: i2lcd.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

ReadADC.o: ReadADC.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

sleep_5ms.o: sleep_5ms.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

wait_for_key_ms.o: wait_for_key_ms.c $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

get_log.o: get_log.S $(MKFILES)
$(CC) $(INCLUDES) $(CFLAGS) -c  $<

include finish.mk
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on January 12, 2017, 06:37:32 pm
I've made another compilation for you to try.

In a few minutes I do the compilation you asked for and I upload it.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on January 12, 2017, 06:44:27 pm
Compilation you asked for.

(http://es.zimagez.com/miniature/compilation2.jpg) (http://es.zimagez.com/zimage/compilation2.php)

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 12, 2017, 07:04:33 pm
Compilation you asked for.

(http://es.zimagez.com/miniature/compilation2.jpg) (http://es.zimagez.com/zimage/compilation2.php)

A greeting.
None off them works.
Well ty for the try.
guess i will be stuck at the 1.11k i got working with display upside/down.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on January 12, 2017, 07:12:57 pm
I'm sorry it did not work for you.

If you need me to compile any other tomorrow i can do it.

Good luck and regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 13, 2017, 06:12:57 am
None off them works.
Well ty for the try.
guess i will be stuck at the 1.11k i got working with display upside/down.

Try the attached files. If they work but have the wrong orientation, take a picture of what's on the screen. This is based on the one you claim worked.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 13, 2017, 04:45:17 pm
None off them works.
Well ty for the try.
guess i will be stuck at the 1.11k i got working with display upside/down.

Try the attached files. If they work but have the wrong orientation, take a picture of what's on the screen. This is based on the one you claim worked.
This work but screen wrong way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on January 13, 2017, 05:01:44 pm
I think hapless has come up with the version you need.

I've taken the liberty of creating a compilation like hapless but with the screen rotated horizontally to see if it serves you.

(http://es.zimagez.com/miniature/mega328st7565v112k702hflip1.jpg) (http://es.zimagez.com/zimage/mega328st7565v112k702hflip1.php)

Greetings
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 13, 2017, 05:33:47 pm
To me, it looks like maybe we're trying too hard: perhaps no flipping is required at all. Here's an "unflipped" version. Makefile included.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Demmacs on January 13, 2017, 05:47:50 pm
To me, it looks like maybe we're trying too hard: perhaps no flipping is required at all. Here's an "unflipped" version. Makefile included.
TYVM both, this 1 works like a charm :)
finaly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 13, 2017, 06:00:22 pm
You're welcome, I'm glad it works.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chai on January 15, 2017, 11:26:27 am
For those with the AY-AT model, which way does the diode go? Is the part number upside down or right side up?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on January 15, 2017, 04:33:39 pm
You can find examples (pictures) in this thread of the protection diode P6KE6V8A (editted)

More help with assembling in the description of:
https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32732193545.html?spm=2114.13010308.0.0.duTKII (https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32732193545.html?spm=2114.13010308.0.0.duTKII)

Info from this thread: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1029919/#msg1029919

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 15, 2017, 05:01:58 pm
The TVS' are available in two versions:
- A for unidirectional
- CA for bidirectional

For a P6KE6V8CA the polarity wouldn't matter, but a P6KE6V8A needs some attention (cathode pointing to Vcc).
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on January 15, 2017, 11:14:24 pm
Digging through the 100+ pages but can't find two of my answers. Did find the some upgrading info and may try that.

I think my display ( de-laminated from the glass) is an ST7576 SPI LCD on a GM328 Tester. It has 12864-1602-v1.1 in the back. Vaguely remember 1.11 firmware when I bought it.

Is it an ST7576 SPI LCD? Where can I get an inexpensive display to resolder to the board?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chai on January 16, 2017, 03:44:17 am
The protection diode P6KE6V8 is bidirectional. Polarity does not matter in this case.

More help with assembling in the description of:
https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32732193545.html?spm=2114.13010308.0.0.duTKII (https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32732193545.html?spm=2114.13010308.0.0.duTKII)

Wow. This is way more info than the ebay listing I bought mine from. Thanks.

For people who ordered one with an acrylic case: Did yours come with a small white plastic tube? What is that for?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on January 16, 2017, 04:47:06 am
lol
that aliexpress seller soldered the test socket in the wrong way around!
 :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: edavid on January 16, 2017, 05:28:51 am
For people who ordered one with an acrylic case: Did yours come with a small white plastic tube? What is that for?

To extend the handle of the ZIF socket.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 16, 2017, 11:17:22 am
I think my display ( de-laminated from the glass) is an ST7576 SPI LCD on a GM328 Tester. It has 12864-1602-v1.1 in the back. Vaguely remember 1.11 firmware when I bought it.

Is it an ST7576 SPI LCD? Where can I get an inexpensive display to resolder to the board?

The ST7576 drives up to 66x102 pixels. Your display is most likely a ST7565 and you can get that from the usual sources of cheap electronic parts ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on January 16, 2017, 04:52:37 pm
Mea culpa, missed the other two TO92s. Please check the power section again. The LED should turn on when the push button is pressed.

finally fixed it, there was a short after R8.
Will try get it on proper PCB, also i have salvaged this LD29150 low drop voltage regulator, it has Inhibit (ttl level on off ?),
what will be the best way to use it ?
should i use the fish type PSU with this regulator and mosfet removed ? directly tie the Gate to inhibit ?

also i have the TL431 (TJ431), should i use it or the internal reference is better than it ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 16, 2017, 05:55:03 pm
The maximium voltage for the inhibit input is 20V. So you could connect it to the power supply via a resistor possibly. A TL431 as voltage reference doesn't make much sense, better use something like a LM4040.
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on January 18, 2017, 10:55:15 pm
So I'm playing around with compiling, I'm using Win AVR to compile, without changing a thing my compiled hex file comes to 101kb for the ST7735 from trunk, the compiled hex for download is 80kb, just looking for a pointer on why this is so? Any help would be appreciated. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on January 18, 2017, 11:24:15 pm
use the gcc from the arduino ide.
it's older and makes smaller code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on January 18, 2017, 11:33:24 pm
Thank you, will give that a shot!  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on January 19, 2017, 07:05:47 am
Is this a new Version?
It measures Temperature, Humidity and test infrared if you test the right sensor (modes 14, 15, 16 ??)
http://www.ebay.com/itm/Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Frequency-Signal-Generator-/172198005211?hash=item2817cd09db:g:aOsAAOSw2xRYPnuL (http://www.ebay.com/itm/Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Frequency-Signal-Generator-/172198005211?hash=item2817cd09db:g:aOsAAOSw2xRYPnuL)

 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on January 19, 2017, 07:17:05 am
That looks like the AY-AT version. It's fully loaded.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 19, 2017, 01:15:05 pm
News from the developer's bench. I've ordered a bunch of coils in the range of 4.7 up to 150mH to tackle the compensation for high value inductors. I'm also waiting for a few servos for testing the new servo checker. The alternative PWM generator with variable frequency and duty cycle for testers with rotary encoder is working fine. The display of MOSFETs includes R_DS and Vf of the body diode. The IR RC detector/decoder can handle a fixed IR receiver module (either probes or fixed). And some PCF8574 based LCD backpacks are on their way to me after a Duncan sent me his modifications for driving such a backpack. But this needs more work to support compatibility with other future extensions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on January 20, 2017, 01:28:02 am
Just wanted to say thanks again stj, that works a treat! Went from 111% to 95.8%, world of difference!  :-+  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 20, 2017, 11:48:16 am
Is this a new Version?
It measures Temperature, Humidity and test infrared if you test the right sensor (modes 14, 15, 16 ??)
http://www.ebay.com/itm/Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Frequency-Signal-Generator-/172198005211?hash=item2817cd09db:g:aOsAAOSw2xRYPnuL (http://www.ebay.com/itm/Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Frequency-Signal-Generator-/172198005211?hash=item2817cd09db:g:aOsAAOSw2xRYPnuL)

 :)

Makes we wonder, what functionality did they remove to fit all that new code in?
Title: Re: $20 LCR ESR Transistor checker project
Post by: muxx on January 20, 2017, 09:59:48 pm
hi everyone

is anyone having problems with mis-detecting BJT as N-JFET? I put a BC548 in and it's detected as N-JFET with all parameters as zeroes.

I have a meter from "EZM Electronics Studio", supported by the mainline FW, with hardware very close to the original meter.
used to work OK, but with the upgrade to 1.12 there's this problem now.
LRC testing is OK. calibration performed.

thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 20, 2017, 10:18:25 pm
What revision? How many times has it happened and how many different transistors have you tried? It can happen during normal operation if
Title: Re: $20 LCR ESR Transistor checker project
Post by: muxx on January 20, 2017, 11:39:41 pm
> What revision?

1.12k
built from source
avr-gcc (GCC) 4.8.1
avr-libc 1.8.0+Atmel3.4.5-1

> you hold the transistor by the leads

use ZIF socket every time.

> there's flux on the circuit board

no, programmed AVR externally, no flux on PCB

> the power supply is low or unstable or noisy

tried two 9V 6LR61 batteries

> the transistor is bad

tried ~20 transistors (more than one specimen of some):

A952, 2N5401, C557, B772 - detected as BJT PNP.

MPS2222, C3421, TPT5609, BD139, 2SC460, 2SC1740 -- "N-JFET Id=0uA@Vg=0mV", then pin configuration.

this "Id=0uA@Vg=0mV" doesn't seem right either.

I think only NPN transistors are mis-detected.

all of the transistors I tried were previously correctly detected by the same meter, but different AVR and FW (stock from EZM).

here's the schematic:

https://www.mikrocontroller.net/topic/345717#3856301 (https://www.mikrocontroller.net/topic/345717#3856301)

thanks for your help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 21, 2017, 12:11:16 am
Since you're saying that everything used to work well, it would make sense to me that the problem would be with the firmware. I haven't used that toolchain version in a long time. Download the latest revision (currently it's 708) of the firmware and compile it with toolchain version 3.5.4. We'll look for other possible causes if that doesn't fix it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: muxx on January 22, 2017, 11:29:43 pm
hi

thanks for your help again.

I started with flashing the pre-built binary from SVN (r710): the result is exactly the same as above.

then I did a bit of a binary search of revisions and discovered that r500 works, but r501 doesn't. again I tried the pre-built binaries (they work) and also rebuilt myself, using 3.4.5, and it also works. so the regression (for this particular board) seems to be caused by this commit:

Code: [Select]
------------------------------------------------------------------------
r501 | kubi48 | 2015-06-03 23:53:36 +0100 (Wed, 03 Jun 2015) | 1 line

LCD_INTERFACE_MODE auch bei Textdisplay

this is bizarre. is there a developers forum/IRC? I could probably investigate further if someone held my hand.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 23, 2017, 12:01:08 am
No problem, but I'm sorry you're still having issues. What you're describing is beyond strange. At this point I would try programming a different MCU with r710.

This is, more or less, the developers' forum. They both come here from time to time. Karl-Heinz is usually more active on the German forum at mikrocontroller.net (http://www.mikrocontroller.net/topic/248078). I'm not aware of a way to chat with either of them, but maybe you could try the email listed on the front page of the manual to set up an IRC session. This forum also allows us to send private messages, but there's no guarantee that they will see it if you decide to send one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 23, 2017, 11:14:57 am
Actually both are quite responsive ;) I'm a little bit puzzled about the problem, since we would see a lot of reports about such an issue. A while ago an user had a strange problem too, and after trying different things it turned out that his version of the compiler caused the problem (the way it did some optimizations). A later version fixed that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheOnlyDocc on January 23, 2017, 01:18:00 pm
Hello,
i have a question. I was assembling this kit
(https://s23.postimg.org/3ykiwnn2z/JD600002.jpg) (https://postimg.org/image/t4lh3hod3/)bild upload (https://postimage.org/index.php?lang=german)
until i got to the two marked Resistors. On the PCB it says 3K3 (3,3Kohm) but i can only find two  33,3Kohm resistors in my set. Is this ok or is 3,3Kohm the right value?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 23, 2017, 02:13:10 pm
The 3k3 mystery :) Please download the attachements in https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1007286/#msg1007286 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1007286/#msg1007286).
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheOnlyDocc on January 23, 2017, 03:06:48 pm
So i downloaded and read the PDF´s but all i can find is that this resistors should be 3,3kohm and not 33,3kohm. If i am wrong please correct me!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on January 23, 2017, 04:00:09 pm
The resistors should be like the printed circuit board labels marked.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheOnlyDocc on January 23, 2017, 04:09:57 pm
Dam! My order from Mouser is already on its way. And i do not have a 3,3kohm resistor here (only in SMD 0805 size). Mhhh have to check if i can get the two resistors at a lokal shop.
Title: Re: $20 LCR ESR Transistor checker project
Post by: edavid on January 23, 2017, 04:27:57 pm
Dam! My order from Mouser is already on its way. And i do not have a 3,3kohm resistor here (only in SMD 0805 size). Mhhh have to check if i can get the two resistors at a lokal shop.

Did you actually measure the resistors?  It's easy to misread the color code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 23, 2017, 06:12:04 pm
Dam! My order from Mouser is already on its way. And i do not have a 3,3kohm resistor here (only in SMD 0805 size). Mhhh have to check if i can get the two resistors at a lokal shop.

So why not just use the SMD components instead? Solder it to one of the vias and extend the other end with a piece of lead clipped from a through-hole resistor. No wait, no need to go to the local store to buy overpriced parts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheOnlyDocc on January 23, 2017, 06:24:42 pm
(https://s24.postimg.org/4asktuwed/IMG_20170305_00063.jpg) (https://postimg.org/image/3y16noe4h/)Bilder hochladen (https://postimage.org/index.php?lang=german)

If i can use the SMD resistors i will definitely use them. I thougt i can not use them because they are only 1/8W and the original resistors are 1/4W.
Title: Re: $20 LCR ESR Transistor checker project
Post by: edavid on January 23, 2017, 06:29:27 pm
If i can use the SMD resistors i will definitely use them. I thougt i can not use them because they are only 1/8W and the original resistors are 1/4W.

If you look at the schematic, you'll see that 1/8W is fine.  (If it wasn't, you could put 4 of them in series parallel to make a 1/2W resistor.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheOnlyDocc on January 23, 2017, 06:48:23 pm
Perfect! And thanks! Will start my Iron right away  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on January 23, 2017, 08:23:11 pm
Don't forget to measure the 33K resistors, if you haven't already. They could have been incorrectly marked, but the correct resistance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 23, 2017, 09:21:02 pm
TheOnlyDocc posted a picture showing a resistance measurement of 33.29k \$\Omega\$. One big problem with posting pictures to forums is that not everyone is always able to view them.

Edit: Hm. This forum doesn't seem to like Greek letters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on January 23, 2017, 10:10:33 pm
Interesting. I don't see any photos in his post. Maybe they're linked from elsewhere, not uploaded to the forum.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 23, 2017, 10:46:10 pm
Now that you mention it... The image is loading for me from postimg.org (https://s24.postimg.org/4asktuwed/IMG_20170305_00063.jpg).
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 24, 2017, 12:43:47 am
I replaced the 7550 regulator in my ST7565 kit tester with a MCP1702 precision regulator, which is more precise than the included TL431 reference.

What should I do now? Remove the 431? disconnect pin PC4 altogether? Or is it enough just to change config.h

EDIT: I just found this in the manual: "If you don’t install the precision voltage reference and you don’t add the relay extension, you should install a pull up resistor R16 to PC4 with a higher resistance value (47k?). This helps the software to detect the missing voltage reference."
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 24, 2017, 11:14:43 am
Yep, the firmware measures the voltage at PC4 and if it's around 2.5V it assumes it's the external voltage reference. The pull-up resistor makes sure that PC4 is outside the expected voltage range, and 100k or 220k would be fine also. The m-firmware behaves the same way, but HW_REF25 (config.h) controls if the code get's included or not.
Title: Re: $20 LCR ESR Transistor checker project
Post by: joystik on January 24, 2017, 05:31:11 pm
Hi guys.

Question: Is there a kit that uses open source firmware and capable of testing zener diodes?
Could you point me in the right direction?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on January 24, 2017, 08:25:41 pm
You can add to any of these kits a simple PWM step up converter with 28V output from eBay for less than $1.  You will also need a small MOSFET as a switch to turn it on plus a few resistors as a voltage divider, current limit and you can test Zeners up to 28v.  You can see a picture of my tester in post #3069.     
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 25, 2017, 06:30:10 pm
Hi guys.

Question: Is there a kit that uses open source firmware and capable of testing zener diodes?
Could you point me in the right direction?

I'm not aware of any kits that do this, but there are ready-made testers with HV for this purpose.

As an aside, it's probably not worth trying to build a zener tester extension for this if it's not already there (although, to each his own). All you need is a power supply with high enough voltage (or even just a simple Joule Thief circuit), a resistor, and a voltmeter. Too easy, and if you have a good meter, possibly more precise, too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: joystik on January 27, 2017, 07:11:02 pm
Thaks for the responses.

I recently got the Color M-Tester model TC-1 and connected a charged cap (by accident :-[). It wouldnt turn on, and an IC, which is unmarked, got really hot. So I opened it and unsoldered the battery(LiPo).

When I soldered it back on, it now turns on but all the tests, even with no test component, return a Cell value of 4.8 to 4.95V.
Do you think theres any hope of fixing it or should I just scrap it and buy a new one?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 27, 2017, 07:15:11 pm
For starters, remove the unmarked chip and see if the tester begins to behave again. I'm assuming it's the protection IC that we're talking about, not the microcontroller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: joystik on January 27, 2017, 07:53:39 pm
For starters, remove the unmarked chip and see if the tester begins to behave again. I'm assuming it's the protection IC that we're talking about, not the microcontroller.

The picture shows the IC im talking about. Its marked U4. U5 also got hot, but now its fine.
I removed the IC, but the unit wont power, so i soldered back on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on January 27, 2017, 08:11:52 pm
Sorry, I was thinking of another tester, one with much fewer ICs in it. In your case, (someone, please correct me if I'm wrong), looks like U1 is the problem. In other words, getting a new tester might not be a bad idea at least until you have a chip like that to replace it with and we have firmware that runs on it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 28, 2017, 02:04:45 am
An eBay seller sent me an HC-05 (cheap Bluetooth module for AVR, www.hc01.com/en (http://www.hc01.com/en)) by mistake. I wonder if it would be possible to use it to send some output from the TT to a smartphone for display. There is an Android app (https://play.google.com/store/apps/details?id=project.bluetoothterminal) specifically for using the HC-05.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jazer on January 28, 2017, 04:01:31 am
This kind of device is handy already, and can generally sniff out an electrolytic vs. ceramic, for example (vloss and esr).

Does anybody know of a reliable means of non-destructively determining the polarity of an electrolytic, in cases where the markings are vague or lost. Any idea of that could be added to the algorithm?
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on January 28, 2017, 04:17:39 am
Does anybody know of a reliable means of non-destructively determining the polarity of an electrolytic, in cases where the markings are vague or lost. Any idea of that could be added to the algorithm?

The traditional way to determine cap polarity it to apply the rated voltage in each direction and the one where the cap explodes is the wrong way.   >:D  but you're no fun and mentioned that "non-destructively" thing.   With the voltage and current available to the tester I doubt you can find a reliable way that would work for all caps... particularly in a reasonable amount of time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 28, 2017, 03:23:15 pm
An eBay seller sent me an HC-05 (cheap Bluetooth module for AVR, www.hc01.com/en (http://www.hc01.com/en)) by mistake. I wonder if it would be possible to use it to send some output from the TT to a smartphone for display. There is an Android app (https://play.google.com/store/apps/details?id=project.bluetoothterminal) specifically for using the HC-05.

I think it would be a nice idea for the ATmega 644/1284 based tester (more flash memory and a hardware serial port). With the current 328 flash is tight.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 28, 2017, 03:30:19 pm
Does anybody know of a reliable means of non-destructively determining the polarity of an electrolytic, in cases where the markings are vague or lost. Any idea of that could be added to the algorithm?

I'd gladly add such a feature if there would be a reliable method to determine the polarity.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Housedad on January 28, 2017, 05:56:23 pm
So many revisions and makers I'm not sure which one to get.  Any recommendations?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 28, 2017, 08:54:57 pm
Look around, because this is the most common question on this thread, and it's been answered numerous times.

https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg864913/#msg864913
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on January 30, 2017, 06:03:01 am
It's not exactly for electrolytic capacitors :
This one detects the outside shield of the capacitor (cool)
https://www.youtube.com/watch?v=BnR_DLd1PDI (https://www.youtube.com/watch?v=BnR_DLd1PDI)

This guy claims that his circuit detects the polarity of the electrolytic capacitor:
https://www.youtube.com/watch?v=GGGQL1c4aEE (https://www.youtube.com/watch?v=GGGQL1c4aEE)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on January 31, 2017, 11:41:02 am
An eBay seller sent me an HC-05 (cheap Bluetooth module for AVR, www.hc01.com/en (http://www.hc01.com/en)) by mistake. I wonder if it would be possible to use it to send some output from the TT to a smartphone for display. There is an Android app (https://play.google.com/store/apps/details?id=project.bluetoothterminal) specifically for using the HC-05.

On the K firmware, you just need to enable the UART on the firmware and you are good to go,see attached pictures.

I use the serial output to log some measurement and I made a small Processing sketch to display the measurements on a PC monitor.
To simplify the code, I changed the firmware to send on the UART the line number of each text string and a "new_line" = ("\r\n") at the end of each line.

I posted some detail one year ago in the following message and I hope Karl-Heinz will add this changes in the main firmware  :)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg875362/#msg875362 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg875362/#msg875362).
Now I fugured out how to wrap the text of the Selection menu...

If someone is interested I attached the custom firmware for the M12864 DIY Kit and the Processing sketch.
I'm also developing a small android app to log the measurements on a phone  :-+.
If you improve the Processing sketch (at the moment it can handle correctly only some of the measurements), or you are developing an app, please share it so this can become a nice addition to this super useful tool.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 31, 2017, 01:24:51 pm
Awesome! I'm thinking about writing a virtual display driver which would send everything via a serial connection, e.g. a bluetooth module. It's just an idea.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on January 31, 2017, 02:55:28 pm
Thank you Markus!!
I look forward to see this working on the m firmware  :-+
As I wrote, having the line number added to each text string sent to the UART and a fix line terminator will semplify alot all the developments of the PC/Mobile Apps.
I think should be good to have the same serial output format on the k and m firmware to use the same apps with both.
Do you know if Karl-Heinz follow this thread or I have to write in the german forum?
I know you are both really busy and doing a greate job, but I would like to know at least if he is interested in adding this changes to the main release.

Have a nice day
    Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 31, 2017, 03:33:27 pm
Please send him an email with the link to your post.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rastro on January 31, 2017, 03:48:33 pm
Is there any way for the component checker be adapted to identify the "foil side" of an un-polarized capacitor?

It seems important to know the orientation of the foil side so it can be attached to the low impedance side to help diminish noise pickup.

This is mentioned in Mr Carlson's Lab video:
https://www.youtube.com/watch?v=BnR_DLd1PDI (https://www.youtube.com/watch?v=BnR_DLd1PDI)

-rastro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 01, 2017, 09:03:08 am
i finally got some time to assembly this AY-AT tester. it was fun enough for me as soldering-newbie.  :)
but when powered it up, it didn't function normally.
after displays "turn-off, transistor & frequency" menu at first start (rotary encoder works for turn it on, but not functioning at this stage), it goes to "V-ext" measurement automatically and stays there until the power jack is unplugged.

does anyone has experienced this problem or have any clue about it?
here's some pics i took :
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 01, 2017, 11:48:27 am
Is there any way for the component checker be adapted to identify the "foil side" of an un-polarized capacitor?

It seems important to know the orientation of the foil side so it can be attached to the low impedance side to help diminish noise pickup.

This is mentioned in Mr Carlson's Lab video:

Could be possible, but would require to earth the circuit's ground. The tester can measure down to 1mV and swap polarity on a DUT. And the ADC should be fast enough to sample 50/60Hz hum.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 01, 2017, 11:57:22 am
i finally got some time to assembly this AY-AT tester. it was fun enough for me as soldering-newbie.  :)
but when powered it up, it didn't function normally.
after displays "turn-off, transistor & frequency" menu at first start (rotary encoder works for turn it on, but not functioning at this stage), it goes to "V-ext" measurement automatically and stays there until the power jack is unplugged.

does anyone has experienced this problem or have any clue about it?

If the ATmega came pre-programmed, I'd suggest to check the circuitry for the rotary encoder, e.g. the resistors, any shorts or bad encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 01, 2017, 04:42:03 pm
Is there any way for the component checker be adapted to identify the "foil side" of an un-polarized capacitor?

It seems important to know the orientation of the foil side so it can be attached to the low impedance side to help diminish noise pickup.

This is mentioned in Mr Carlson's Lab video:

Could be possible, but would require to earth the circuit's ground. The tester can measure down to 1mV and swap polarity on a DUT. And the ADC should be fast enough to sample 50/60Hz hum.

How about just using one of the pins to generate a signal and using that pin's connector as a sleeve into which a capacitor would be inserted? No need for grounding then and no need to use one's body as an antenna, but I wonder if it's going to be strong enough to be measured while weak enough not to penetrate the foil too strongly so that the difference on the pins can be measured reliably.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 01, 2017, 05:34:35 pm
i finally got some time to assembly this AY-AT tester. it was fun enough for me as soldering-newbie.  :)
but when powered it up, it didn't function normally.
after displays "turn-off, transistor & frequency" menu at first start (rotary encoder works for turn it on, but not functioning at this stage), it goes to "V-ext" measurement automatically and stays there until the power jack is unplugged.

does anyone has experienced this problem or have any clue about it?

If the ATmega came pre-programmed, I'd suggest to check the circuitry for the rotary encoder, e.g. the resistors, any shorts or bad encoder.

please excuse my stupid question as i'm a newbie, but how to check for bad encoder?
does it by in-circuit check or i have to desolder it first?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rastro on February 01, 2017, 05:45:55 pm
Is there any way for the component checker be adapted to identify the "foil side" of an un-polarized capacitor?

It seems important to know the orientation of the foil side so it can be attached to the low impedance side to help diminish noise pickup.

This is mentioned in Mr Carlson's Lab video:

Could be possible, but would require to earth the circuit's ground. The tester can measure down to 1mV and swap polarity on a DUT. And the ADC should be fast enough to sample 50/60Hz hum.

How about just using one of the pins to generate a signal and using that pin's connector as a sleeve into which a capacitor would be inserted? No need for grounding then and no need to use one's body as an antenna, but I wonder if it's going to be strong enough to be measured while weak enough not to penetrate the foil too strongly so that the difference on the pins can be measured reliably.

Couldn't the test look for noise level (predominately 50/60Hz) differences between the two pins connected to the component even without a ground reference?   
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 02, 2017, 05:57:03 pm
please excuse my stupid question as i'm a newbie, but how to check for bad encoder?
does it by in-circuit check or i have to desolder it first?

Check the encoder's button for short circuit first. Desolder if there is continuity across its pins when it's not pressed.

Couldn't the test look for noise level (predominately 50/60Hz) differences between the two pins connected to the component even without a ground reference?   

The original design (not the one I proposed) relies on grounding to create shielding effect and attenuate the noise you pick up. Without proper grounding, your device's ground may make an even better antenna than your body, so the results would be wrong or inconclusive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 03, 2017, 08:19:31 am
please excuse my stupid question as i'm a newbie, but how to check for bad encoder?
does it by in-circuit check or i have to desolder it first?

Check the encoder's button for short circuit first. Desolder if there is continuity across its pins when it's not pressed.

continuity only occurs between two big pins at side of the encoder (holder pins?). no continuity at 5 other pins.
if the encoder pressed, the two pins at top, which facing toward the LCD, has continuity.

is that looks ok?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 03, 2017, 08:47:24 am
Seems fine. Someone else had a similar problem and solved it (in post 2546 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1018470/#msg1018470)) by changing transistors. Make sure that your transistors are all soldered with the correct pins in the right places. If they are, maybe one is faulty.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 04, 2017, 10:53:56 am
thank you. i'll check the transistors.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: 1413 on February 04, 2017, 11:15:59 am
The thermal protection of 7550 kicks in and makes noise on the Vcc. You will find it hot when use 12v source but quite warm with 9v source. I use 2x 3.7 Li-ion battery connect in series, but found it troublesome with recharge circuit.
I am on process of modifying firmware based on 1.12k to work with single 3.7 li-ion without need of DC-DC step up circuit. Already got some progresses. But now I want to change xtal to 16MHz for the TFT draws faster.

PS: Picture below is my firmware *development kit*  LOL, which 8 ic sockets stack on each other for easy removing the atmega328p
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 04, 2017, 11:46:12 am
The thermal protection of 7550 kicks in and makes noise on the Vcc. You will find it hot when use 12v source but quite warm with 9v source. I use 2x 3.7 Li-ion battery connect in series, but found it troublesome with recharge circuit.
I am on process of modifying firmware based on 1.12k to work with single 3.7 li-ion without need of DC-DC step up circuit. Already got some progresses. But now I want to change xtal to 16MHz for the TFT draws faster.

With 3.7V the tester won't be able to check as much components as with 5V. Just saying ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 04, 2017, 03:24:52 pm
The thermal protection of 7550 kicks in and makes noise on the Vcc. You will find it hot when use 12v source but quite warm with 9v source. [...]

Sounds like your LDO is oscillating. Try adding capacitors or change the regulator to something like LM7805 for stable operation. Thermal protection would shut off the circuit, not add noise to it. It wouldn't be much of a protection if it just sat there making noise. This is one of those cases where it makes much more sense to change the hardware than the software.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 1413 on February 04, 2017, 03:55:20 pm
The thermal protection of 7550 kicks in and makes noise on the Vcc. You will find it hot when use 12v source but quite warm with 9v source. I use 2x 3.7 Li-ion battery connect in series, but found it troublesome with recharge circuit.
I am on process of modifying firmware based on 1.12k to work with single 3.7 li-ion without need of DC-DC step up circuit. Already got some progresses. But now I want to change xtal to 16MHz for the TFT draws faster.

With 3.7V the tester won't be able to check as much components as with 5V. Just saying ;)
Make sense :D

Anyway, I recompiled the firmware with F_CPU = 16Mhz.

Turn out 7550 sucks as V-Out to be 6v!!! That's why m328p acted weird when I changed 8Mhz to 16Mhz crystal.

I still have no idea why just simple replacement of xtal can make change in voltage.

So, I bend middle leg of 78L05 to the side (into 2-3-1) and replace the trouble maker 7550. Now it gets 4.93v VCC on the TFT screen and similar value on my voltmeter.

Finally it works at 16Mhz, and noticeably faster in rendering text on the screen.

Edit: with extra cable to the TFT, it sometimes misses / misplaces some dots, thus the data sent to TFT is not integrity.

Sounds like your LDO is oscillating. Try adding capacitors or change the regulator to something like LM7805 for stable operation. Thermal protection would shut off the circuit, not add noise to it. It wouldn't be much of a protection if it just sat there making noise. This is one of those cases where it makes much more sense to change the hardware than the software.
Yeah, you're right. It also heat up fast because of differentiate in input voltage and output voltage, as it has to take out 7v out of 12v and transfer it into heat. Maybe 7v different is too much for 7550.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on February 04, 2017, 10:47:19 pm
I have been using an 18650 Li-Ion battery (which lasts for ever) with exactly the same charging/protection board and step up converter as you are. 

The only thing I set the step up converter to 5V output and eliminated completely the on board original 5V linear regulator so everything is powered from the step up 5V output without any problems.  Se my original post, #3069.

Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on February 05, 2017, 05:47:31 pm
I find this tool highly useful for measuring ESR even in circuit but one thing that really bothers me is those grabber leads.

While they're okay for out of circuit component testing they're a pain for in circuit quick measurements.

Mine does not have a case so banana terminals is not an option.

I'm thinking to  buy a cheap set of multimeter probes cut off the shrouded banana plugs and solder the leads directly to the 1 and 3 pins of the tester.
Re-calibrating the tester to zero out any resistance/capacitance of the longer wires should do the trick ,right?
Another problem is that the pin holes are too small to fit a 12-14awg wire so I'll have to improvise a bit there..


Has anybody tried something similar?
I think that some kind smd tweezers or needle type leads would really make things easier for repair jobs..
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on February 05, 2017, 06:31:15 pm
I find this tool highly useful for measuring ESR even in circuit but one thing that really bothers me is those grabber leads.

While they're okay for out of circuit component testing they're a pain for in circuit quick measurements.

Mine does not have a case so banana terminals is not an option.

I'm thinking to  buy a cheap set of multimeter probes cut off the shrouded banana plugs and solder the leads directly to the 1 and 3 pins of the tester.
Re-calibrating the tester to zero out any resistance/capacitance of the longer wires should do the trick ,right?
Another problem is that the pin holes are too small to fit a 12-14awg wire so I'll have to improvise a bit there..


Has anybody tried something similar?
I think that some kind smd tweezers or needle type leads would really make things easier for repair jobs..

Something like that ?:

(http://es.zimagez.com/miniature/img20170203123138.jpg) (http://es.zimagez.com/zimage/img20170203123138.php)

(http://es.zimagez.com/miniature/img20170205192505.jpg) (http://es.zimagez.com/zimage/img20170205192505.php)

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stecor on February 06, 2017, 09:53:01 am
Hello All, thanks for the great wealth of info thus far.

I also have a T4 Chinese clone, which I "upgraded" with a rotary encoder and upgraded the firmware to 1.12k (using a custom ISP cable connected to an USBASP adapter).

The clone has SMT resistors with 1% accuracy, the PCB is okay-ish, including a 2.5% Voltage ref and it's compliant to the newer version of the schematic.

I have the following questions:
1. After downloading the trunk, I could use the default MEGA328-T3-T4 .hex and .eep to upload the firmware, and it sort of works:
- the tester is now functional including the rotary encoder I added.
- calibration can be performed successfully, but:
Issues/Concerns:
Issue 1: Capacitor ESR is off - e.g. capacitors I used to read with a 0.1 - 0.2 ohm ESR now show as 0.00 Ohm ESR
Adding a .7 Ohm resistor in series with a 0.00 ESR capacitor yields a .35 Ohm ESR (that is off by .35 Ohm!!!).

Calibration was performed multiple times with both a "known good" very low ESR 2500 uF electrolytic as well as a 2uF ceramic (unknown quality). Really crappy caps (which used to read 2-3 Ohm, still show up with appreciable ESR, albeit I believe smaller)

Issue 2: Sometimes (especially when turning the rotary encoder during a measurement) I get the "Not Calibrated" message. If I restart the meter, the calibration is OK. Going in the menu, I can see the calibration data

2. I looked at the software, and in the Makefile, I could see the following config: CFLAGS += -DNO_AREF_CAP which is basically saying there is no 1nF cap at Aref. My board has one, so I would like to comment out the above. I could take the cap out, but it seems like a good thing to have, so would rather keep it, even if it slows down measurement some.

Issue is that, building the project with WinAvr yields 107% !!!! Flash utilization, thus I cannot flash the FW. I used the -O3 and -Os options, but no dice.
I have also downloaded the updated Atmel AVR toolchain and updated my WinAvr to the latest toolset, however in that case, I get an error related to EEPROM defines (__eerd_m328 or similar). I believe this is due to the EEPROM access functions.

Thus, please can you help me with the following:

1. Help troubleshoot the cause of the ESR discrepancy I see with the meter
2. Please point me in the right direction in order to compile the FW successfully (within the 32k of Flash available :) )


Thank you!!!

If I can provide any additional info, please let me know, thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 06, 2017, 11:33:03 am
If the 2.5v reference is just a TL431, please replace it with a LM4040 or LM285. If the 5V LDO is a MCP1702-5002 or another one with similar specs remove the TL431 without replacing it. The Transistor Tester is no precision instrument, but a resistor with 0.7 Ohms is measured correctly in most cases if the tester is adjusted. The best cap for the adjustment procedure is a film cap with 220nF up to a few µF. Are there any contact issues with the ZIF or probe leads? Those could cause low measurement values to be off a little bit. The issue with the rotary encoder is strange, since the check for an adjusted tester is based on a value stored in the EEPROM. The external cap at the AREF pin is recommended and its capacitance has an inpact on some timing of the ADC when switching voltage references. For a 1nF cap the k-firmware doesn't require to be told about that in the Makefile. But it's also fine to enable it. Older versions of avr-gcc are known to create large binaries. There are several posts in this thread about this and you'll find recommended versions in those posts. Could you please post the exact compiler error regarding the EEPROM functions?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 06, 2017, 01:24:40 pm
Seems fine. Someone else had a similar problem and solved it (in post 2546 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1018470/#msg1018470)) by changing transistors. Make sure that your transistors are all soldered with the correct pins in the right places. If they are, maybe one is faulty.
so i've desoldered the transistors and checked them with DMM.
9012 & 9014 looks fine (refers to some how to check transistor is bad/good videos on youtube).
as 7550 and TL431 are not transistors, i don't know how to check them.

i didn't desolder TL431 yet, but with 7550 i have these readings with DMM (diode test function):
* Vin  --> Vout  = 1070 ohm
* Vout --> Vin   = 560 ohm
* Vout --> GND   = 0L
* GND  --> Vout  = 825 ohm
* Vin  --> GND   = 740 ohm
* GND  --> Vin   = 0L

could that readings be used to tell if 7550 is bad/good?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stecor on February 06, 2017, 01:39:59 pm
If the 2.5v reference is just a TL431, please replace it with a LM4040 or LM285. If the 5V LDO is a MCP1702-5002 or another one with similar specs remove the TL431 without replacing it. The Transistor Tester is no precision instrument, but a resistor with 0.7 Ohms is measured correctly in most cases if the tester is adjusted. The best cap for the adjustment procedure is a film cap with 220nF up to a few µF. Are there any contact issues with the ZIF or probe leads? Those could cause low measurement values to be off a little bit. The issue with the rotary encoder is strange, since the check for an adjusted tester is based on a value stored in the EEPROM. The external cap at the AREF pin is recommended and its capacitance has an inpact on some timing of the ADC when switching voltage references. For a 1nF cap the k-firmware doesn't require to be told about that in the Makefile. But it's also fine to enable it. Older versions of avr-gcc are known to create large binaries. There are several posts in this thread about this and you'll find recommended versions in those posts. Could you please post the exact compiler error regarding the EEPROM functions?


Thank you! I appreciate your taking time taking to noobs like me ;)

First of all, yep, you nailed it completely - the ZIF went partially bad... I did not notice it right away, but the "main" 1-2-3 set (the one that is used most frequently) has a bent contact, hence the higher resistance value. Re-doing the tests in the un-damaged pins cleared the issues. I need to source a proper ZIF socket now.

Thanks for the guidance on regulators - unfortunately, both are less than stellar - the 2.5 reference is a 431, and the 5V is an 78L05. I guess next step is replacing them both.

On the compiler issue, I did get an issue with Avast (I use the free version) and it did complain about potentially malicious content during the install, so I simply disabled the AV shield and re-did the install - and marvel of marvels - it works beautifully... compiles with no issues @95% or so.

On the precision matter you mentioned, I still think it's a pretty useful tool. Unless I am grossly mistaken, you are the Markus that forked the trunk, so thank You, Karl-Heinz and the other Markus too :)  The main use case for me is capacitance & ESR (mostly ESR) and for capacitance I find it accurate enough for my needs by comparing to the other meters I have. ESR is the Godsend, since this is what I bought it for. BTW - if it would be possible to measure ESR at different frequencies, that would again be pretty useful - 100KHz to 1MHz would be awesome!!! :)


Thanks again and have a great day!



Title: Re: $20 LCR ESR Transistor checker project
Post by: Stecor on February 06, 2017, 01:51:14 pm
so i've desoldered the transistors and checked them with DMM.
9012 & 9014 looks fine (refers to some how to check transistor is bad/good videos on youtube).
as 7550 and TL431 are not transistors, i don't know how to check them.

i didn't desolder TL431 yet, but with 7550 i have these readings with DMM (diode test function):
* Vin  --> Vout  = 1070 ohm
* Vout --> Vin   = 560 ohm
* Vout --> GND   = 0L
* GND  --> Vout  = 825 ohm
* Vin  --> GND   = 740 ohm
* GND  --> Vin   = 0L

could that readings be used to tell if 7550 is bad/good?

TL431 is a ref voltage supply, so you can easily check it in circuit - provided you have a decent voltmeter - you simply measure the voltage between PD4 and ground; it should be pretty close to 2500mV - WITH the tester working (when shut down, the voltage is 0...). Obviously, a 1% DMM is a must there... I am not sure what the 7550 is, but if it's the supply regulator, again, you can check the Vcc rail voltage... 5000mV +/- 1% and you should be fine.

As Madires mentioned above, you may wish to look for a better spec supply regulator and/or reference supply.

Title: Re: $20 LCR ESR Transistor checker project
Post by: 1413 on February 06, 2017, 02:29:42 pm
Issue is that, building the project with WinAvr yields 107% !!!! Flash utilization, thus I cannot flash the FW. I used the -O3 and -Os options, but no dice.
I have also downloaded the updated Atmel AVR toolchain and updated my WinAvr to the latest toolset, however in that case, I get an error related to EEPROM defines (__eerd_m328 or similar). I believe this is due to the EEPROM access functions.

I use the cygwin + avr compiler comes with arduino ide for compiling and Avrdudess for fuse burning and firmware uploading
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 06, 2017, 03:55:27 pm
so i've desoldered the transistors and checked them with DMM.
9012 & 9014 looks fine (refers to some how to check transistor is bad/good videos on youtube).
as 7550 and TL431 are not transistors, i don't know how to check them.

i didn't desolder TL431 yet, but with 7550 i have these readings with DMM (diode test function):
* Vin  --> Vout  = 1070 ohm
* Vout --> Vin   = 560 ohm
* Vout --> GND   = 0L
* GND  --> Vout  = 825 ohm
* Vin  --> GND   = 740 ohm
* GND  --> Vin   = 0L

could that readings be used to tell if 7550 is bad/good?

The voltage regulator is an IC, and the way to tell if it's working is to measure the voltage at its output. It should be around 5V. Now that you have all the transistors out of the circuit, put back the regulator and short out the holes of where the emitter and collector of your 9012 would be. If I'm not mistaken, that's your T3. The tester should turn on and go through a normal test cycle. It should not go into menu or show Vext. It will not react to any button presses in this state. Let me know how it goes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 06, 2017, 04:08:28 pm
2. I looked at the software, and in the Makefile, I could see the following config: CFLAGS += -DNO_AREF_CAP which is basically saying there is no 1nF cap at Aref. [...]

The name is misleading. This is how it should be for as long as you don't have the commonly used 100nF capacitor there. Could as well have been something like -DMUCH_SMALLER_THAN_100nF_OR_NO_AREF_CAP. If you get rid of that flag, it would assume 100nF (i.e., you'll be shooting yourself in the foot).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 07, 2017, 11:03:18 am
so i've desoldered the transistors and checked them with DMM.
9012 & 9014 looks fine (refers to some how to check transistor is bad/good videos on youtube).
as 7550 and TL431 are not transistors, i don't know how to check them.

i didn't desolder TL431 yet, but with 7550 i have these readings with DMM (diode test function):
* Vin  --> Vout  = 1070 ohm
* Vout --> Vin   = 560 ohm
* Vout --> GND   = 0L
* GND  --> Vout  = 825 ohm
* Vin  --> GND   = 740 ohm
* GND  --> Vin   = 0L

could that readings be used to tell if 7550 is bad/good?

The voltage regulator is an IC, and the way to tell if it's working is to measure the voltage at its output. It should be around 5V. Now that you have all the transistors out of the circuit, put back the regulator and short out the holes of where the emitter and collector of your 9012 would be. If I'm not mistaken, that's your T3. The tester should turn on and go through a normal test cycle. It should not go into menu or show Vext. It will not react to any button presses in this state. Let me know how it goes.
ok, i've put back 7550 to its place and leave 9014 (2pcs) and 9012 out of circuit, then short out the holes of emitter and collector of 9012 (it should be the outer legs of 9012, right?) but nothing happens, it doesn't turn on.  :-//

i just noticed that the board has top & bottom traces. does that mean the solder tin should goes through bottom-up on each component's pin?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 07, 2017, 05:48:28 pm
I'm really scratching my head here. Yes, those should be the two outer holes. Can you measure voltage across the component marked P6KE6V8 while the short is in place?

i just noticed that the board has top & bottom traces. does that mean the solder tin should goes through bottom-up on each component's pin?

Only if your board is damaged or poorly made. Normally, the vias conduct from top to bottom even when no component is inserted.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 08, 2017, 04:57:08 am
I'm really scratching my head here. Yes, those should be the two outer holes. Can you measure voltage across the component marked P6KE6V8 while the short is in place?
if you meant this smd diode component (pic attached), it just marked "AK" on mine. (cheaper one?  :palm:)
with 9012 holes shorted, i got 4.96v measured on that diode.
while at 7550 pins, i got Vin = 8.03v , Vout = 4.96v.
input power source was at 8.50v.

just to make it clearer, the 2 pcs of 9014 transistor should be out-of-circuit also while doing this measurement, right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 08, 2017, 05:24:55 am
Your socket is covering the silk-screened markings. It's the right part though. But now I'm completely lost. Vcc is correct, so you should at least be seeing the backlight come on. Wait, please tell me you are doing this with the LCD connected. Otherwise you can't tell if the tester is on or off, much less whether it goes through the normal routine or not!

just to make it clearer, the 2 pcs of 9014 transistor should be out-of-circuit also while doing this measurement, right?

Doesn't matter. But keep them out for now.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 08, 2017, 05:58:52 am
Your socket is covering the silk-screened markings. It's the right part though. But now I'm completely lost. Vcc is correct, so you should at least be seeing the backlight come on. Wait, please tell me you are doing this with the LCD connected. Otherwise you can't tell if the tester is on or off, much less whether it goes through the normal routine or not!
you've nailed on that one.
yes, i was not put the LCD connected, just watched for the red LED was not turned on.  :palm:

ok now with LCD connected i got Battery&VCC measurement display at start, then it displays:
* "Cell!" with some numbers in mV

for some seconds, it displays blinking "Short Probes!"

*update :
it actually gives some different displays when the input jack is disconnected-reconnected.
now it displays "No, unknown, or damaged part?" although i put 1Mohm resistor on pin 1-3 of the zif socket.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 08, 2017, 07:36:57 am
You can remove the short and put all transistors back in. What kind of flux are you using?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 08, 2017, 12:01:28 pm
You can remove the short and put all transistors back in. What kind of flux are you using?
when i was about to resolder the transistors back, i noticed that i've carelessly lifted the top side trace of right pin (3rd pin) of 9014 next to 7550 (see pic below...  :palm:).
however, it seem that it doesn't have top side traces connected to it, only its bottom side has. the bottom side is fine though.
but when the tester was turned on, it still displayed Battery&Vext measurement like before..  :palm:

is it possible that the lifted trace caused the problem?


about the flux, i used a non-brand liquid flux in pen applicator (bought in local store) when assembled the tester. it made the solder tin melted fast, but it less shinny after it cool down.
when i desoldered and soldered back, i use lotfett brand (i don't know it is original or not.. it is in hard plastic container), it is in paste-form and the solder tin result is shinny.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jleg on February 08, 2017, 04:38:12 pm
about the flux, i used a non-brand liquid flux in pen applicator (bought in local store) when assembled the tester. it made the solder tin melted fast, but it less shinny after it cool down.
when i desoldered and soldered back, i use lotfett brand (i don't know it is original or not.. it is in hard plastic container), it is in paste-form and the solder tin result is shinny.

i once got quite frustrated, because it seemed each project i was working on had strange issues of all kinds. After some "deeper investigation" i discovered, that my used "non-brand flux pen" sequested something which had only a few ohms resistance, even if applied to a paper and fully dried..  :o
After "fixing" this my success rate went up again!  8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 08, 2017, 07:12:38 pm
It's difficult to tell from the photo... it just looks like brown spot, but it's possible that the transistor leg isn't connected to the top of the board at all. But only you know the answer ... test the continuity with you multimeter.

Also, the yellow capacitor in front of it looks like it has a dry joint. In the other previous photos you posted, there is too much solder on resistors etc. You should search around Youtube for some soldering tutorials. Maybe Dave has some too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on February 08, 2017, 09:57:22 pm
It does look like quite a few solder joints are not as they should be. Are you using solder with lead/flux core? It should look more cone shaped rather than balls and if lead based it should be shiny. You want to make sure to heat up the pad and the lead, but not too hot, there is not a lot of mass on the board, so if using leaded solder probably 270-290 Celsius should be sufficient.  I only used flux on the SMD components for mine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 09, 2017, 02:25:53 am
Don't forget though that you're looking at the side opposite to where soldering was done. There's likely a good electrical connection despite the way it looks from the top.

is it possible that the lifted trace caused the problem?

No, you said it yourself, the trace is not connected on the top of the board.

about the flux, i used a non-brand liquid flux in pen applicator (bought in local store) when assembled the tester. it made the solder tin melted fast, but it less shinny after it cool down.
when i desoldered and soldered back, i use lotfett brand (i don't know it is original or not.. it is in hard plastic container), it is in paste-form and the solder tin result is shinny.

i once got quite frustrated, because it seemed each project i was working on had strange issues of all kinds. After some "deeper investigation" i discovered, that my used "non-brand flux pen" sequested something which had only a few ohms resistance, even if applied to a paper and fully dried..  :o
After "fixing" this my success rate went up again!  8)

This. To me it seems like your no-name brand flux contains some acid which is somewhat conductive. You need to wash, clean and dry your board really-really well. You've tested the transistors, so the there are only two things I can think of now that could be causing the problems you're experiencing: conductive flux or bad ATMega. I think it's the flux. Clean your board inside and out, then clean it again. I hope this helps.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on February 10, 2017, 06:49:49 pm
I have a couple firmware questions. 

1) My understanding is that the accuracy of the measurements depends on the accuracy of external 2.5V Reference voltage (assuming you have one), is that correct?

2) If you don't have an external voltage reference then the firmware is using the Vcc as a reference voltage.  Dose the software automatically checks the voltage on the reference voltage pin or you have to change the firmware and tell it that you don't have an external voltage reference?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 10, 2017, 07:08:58 pm
Yes, the firmware (k and m) uses the external 2.5V reference to determine the offset of Vcc (5V). Therefore the reference should be much more accurate than the 5V voltage regulator. But you don't need to have the external reference, you could also have an accurate LDO or measure the output voltage of the voltage regulator and adjust the value in the firmware. The presence of the external reference is checked by the firmware. If there's none the tester assumes that Vcc is 5V. The m-firmware has additionally a configuration switch for enabling the external reference (disabling it, saves a few bytes flash).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 11, 2017, 05:35:06 am
i once got quite frustrated, because it seemed each project i was working on had strange issues of all kinds. After some "deeper investigation" i discovered, that my used "non-brand flux pen" sequested something which had only a few ohms resistance, even if applied to a paper and fully dried..  :o
After "fixing" this my success rate went up again!  8)

It's difficult to tell from the photo... it just looks like brown spot, but it's possible that the transistor leg isn't connected to the top of the board at all. But only you know the answer ... test the continuity with you multimeter.

Also, the yellow capacitor in front of it looks like it has a dry joint. In the other previous photos you posted, there is too much solder on resistors etc. You should search around Youtube for some soldering tutorials. Maybe Dave has some too.

This. To me it seems like your no-name brand flux contains some acid which is somewhat conductive. You need to wash, clean and dry your board really-really well. You've tested the transistors, so the there are only two things I can think of now that could be causing the problems you're experiencing: conductive flux or bad ATMega. I think it's the flux. Clean your board inside and out, then clean it again. I hope this helps.
hi, i'm sory i had quite busy time i wasn't able to sit in front of my computer these few days.
thank you very much for all your comments & suggestions, it really helps in my learning curve about soldering.
yes, i also think that the problem caused by my limited soldering experience and tools i used. lesson learned.  :)

btw, in order to wash the board, is it ok to just dip it in isoprophyl alcohol (with ATMega chip removed) and brush it?
or is it better to desolder all the components first, wash the board clean and re-solder the components back?
Title: Re: $20 LCR ESR Transistor checker project
Post by: 1413 on February 11, 2017, 03:55:47 pm
btw, in order to wash the board, is it ok to just dip it in isoprophyl alcohol (with ATMega chip removed) and brush it?
or is it better to desolder all the components first, wash the board clean and re-solder the components back?

Just use isopropyl alcohol, tooth brush and tissue to remove any residues or flux. Don't need to desolder anything.

I only use extra flux to help remove excess solder from solder bridges or fix overheated solder joints since apply heat too long will burn the flux. Otherwise, the amount of flux inside the solder wire is enough. But of-course, I would clean up the remain flux after finish soldering.
Title: Re: $20 LCR ESR Transistor checker project
Post by: avrishuvorlaz on February 12, 2017, 04:06:38 am
To me, it looks like maybe we're trying too hard: perhaps no flipping is required at all. Here's an "unflipped" version. Makefile included.

Mr hapless, master of LCR firmwares, I used your "TransistorTester (as above, but no flipping).zip" on my device which was originally on the "Mtester" firmware, and it works a treat... but one thing I have noticed is this - the characters seem to be shifted too far to the right by 0.5-1 characters - do you know how I would resolve this? The typeface is nice and bold - maybe a little TOO bold, at the expense of the chars flowing off the right hand side of the LCD.

Here is the exact model I own, together with the graphics overflow (right hand side of LCD) shown - I bought from "comecome28" on eBay, this listing: http://www.ebay.co.uk/itm/112259073834 (http://www.ebay.co.uk/itm/112259073834)

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-9/16711815_10155026937607937_6794219227385603171_n.jpg?oh=dbaabafac774497952df01f4f0c52372&oe=5900C1F5)

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-9/16729155_10155026937682937_3137555683562381927_n.jpg?oh=0d6fcfb8426cc751192c8bde8d6dba1a&oe=5949AFD2)

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-9/16711495_10155026937732937_4922224851098282844_n.jpg?oh=eb930d2922babcba094ea24154c1de5f&oe=5939E6F6)

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-9/16708229_10155026937857937_2327228873337651422_n.jpg?oh=5f426ee8505dac244f4568322e88b113&oe=5935FA62)

Thanks Sir.  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 12, 2017, 06:52:32 am
Just use isopropyl alcohol, tooth brush and tissue to remove any residues or flux. Don't need to desolder anything.

I only use extra flux to help remove excess solder from solder bridges or fix overheated solder joints since apply heat too long will burn the flux. Otherwise, the amount of flux inside the solder wire is enough. But of-course, I would clean up the remain flux after finish soldering.
hi, thank you for the tips.
i have brushed it with IPA, top&bottom side of it, and have some progress after that.   :-+

the tester now is able to do :
  * selftest works (shows v1.12 at the end)
  * LEDs & diode test works
  * capacitor test is quite accurate with 5-10% tolerance
  * BJT NPN transistor test works
  * rotary encoder works a little awkward at menu selection (rotate left goes down, rotate right goes up - i don't know it is normal or not, but it works)

what's not working :
  * testing IRF9540N P-mosfet (new stock one) recognized as dual-diode with wrong pin numbers, and different result when the transistor put reversed. (see attached pics)
  * testing N-mosfet recognized as dual-diode too.
  * unable to test 100K & 1M ohm resistor, result as "no, unknown or damaged part"

what do you think guys?
based on what's working and not working, is my tester still has problem? or it has functioning as it is?


*UPDATE*
just noticed that the tester failed to detect base, emitter and collector of D965 BJT NPN transistor (see 3rd pic).
according to D965 datasheet, pin 2 is collector, while the tester gives result that pin 2 is emitter.   :palm:
maybe my tester is still not work normally?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 12, 2017, 12:08:49 pm
Mr hapless, master of LCR firmwares, I used your "TransistorTester (as above, but no flipping).zip" on my device which was originally on the "Mtester" firmware, and it works a treat... but one thing I have noticed is this - the characters seem to be shifted too far to the right by 0.5-1 characters - do you know how I would resolve this? The typeface is nice and bold - maybe a little TOO bold, at the expense of the chars flowing off the right hand side of the LCD.

It's the horizontal offset LCD_ST7565_H_OFFSET. In case it's set to 4, change it to 0, or vice versa. That is caused by the way the LCD is connected to the controller and if horizontal flip is enabled or not. The controller supports 132 pixels but the display has only 128.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 12, 2017, 02:16:40 pm
Meanwhile I've got a few cheap and crappy RC servos for testing the servo check function. Based on them the best range for the pulse length seems to be 0.5 - 2.5 ms (instead of 1 - 2 ms). Do you got similar experience? I've also received some PCF8574 based LCD backpacks which work fine. The new m-firmware version will have a simple I2C framework supporting the ATmega's TWI and bit-bang I2C. So we can add more I2C clients. While investigating LCD backpacks I saw also some MCP23008 based ones. A good opportunity if you like to sponsor the m-firmware ;) Or do you got any other I2C wishes?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 12, 2017, 08:54:11 pm
Mr hapless, master of LCR firmwares, [...]

Heh, that's very kind of you, but there are people around here who are much more deserving of the title...

[...] I used your "TransistorTester (as above, but no flipping).zip" on my device which was originally on the "Mtester" firmware, and it works a treat... but one thing I have noticed is this - the characters seem to be shifted too far to the right by 0.5-1 characters - do you know how I would resolve this? The typeface is nice and bold - maybe a little TOO bold, at the expense of the chars flowing off the right hand side of the LCD.

The fonts are monospaced, so it's the width of the characters that matters, otherwise bold ones can be the same width as the thin ones. It's more of a matter of taste. As madires pointed out, the problem is with the offset that was deliberately used so that the exact same issue would be fixed for devices that have their screens rotated 180 degrees. I'm attaching a build that should fix this for you, but it doesn't use the exact same Makefile, so please let me know if I accidentally broke something.

Note: I made some (very few) slight changes to the output of the code. They are not even worth mentioning, but don't be surprised if you see that "Version1.13" now has a space in it or that "4 * ->|-" shows as "4 x ->|-".

[...]
i have brushed it with IPA, top&bottom side of it, and have some progress after that.   :-+
[...]
maybe my tester is still not work normally?

I'm very happy that it's finally starting to work, but you need to need to give it at least one more go with water (try to dry it as quickly as possible!) and then alcohol. Clean very thoroughly. You'll probably also want to clean between the pins of the MCU, too (just in case). Just make sure it's completely dry before powering up the board, and, of course, be gentle enough not to damage anything while you're at it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: avrishuvorlaz on February 12, 2017, 11:22:15 pm
Mr hapless, master of LCR firmwares, [...]

Heh, that's very kind of you, but there are people around here who are much more deserving of the title...

[...] I used your "TransistorTester (as above, but no flipping).zip" on my device which was originally on the "Mtester" firmware, and it works a treat... but one thing I have noticed is this - the characters seem to be shifted too far to the right by 0.5-1 characters - do you know how I would resolve this? The typeface is nice and bold - maybe a little TOO bold, at the expense of the chars flowing off the right hand side of the LCD.

The fonts are monospaced, so it's the width of the characters that matters, otherwise bold ones can be the same width as the thin ones. It's more of a matter of taste. As madires pointed out, the problem is with the offset that was deliberately used so that the exact same issue would be fixed for devices that have their screens rotated 180 degrees. I'm attaching a build that should fix this for you, but it doesn't use the exact same Makefile, so please let me know if I accidentally broke something.

Note: I made some (very few) slight changes to the output of the code. They are not even worth mentioning, but don't be surprised if you see that "Version1.13" now has a space in it or that "4 * ->|-" shows as "4 x ->|-".

[...]
i have brushed it with IPA, top&bottom side of it, and have some progress after that.   :-+
[...]
maybe my tester is still not work normally?

I'm very happy that it's finally starting to work, but you need to need to give it at least one more go with water (try to dry it as quickly as possible!) and then alcohol. Clean very thoroughly. You'll probably also want to clean between the pins of the MCU, too (just in case). Just make sure it's completely dry before powering up the board, and, of course, be gentle enough not to damage anything while you're at it.

Ah, thank you, Sir, you are very kind. How does one know which way is the "normal" orientation of the LCD, and which way is 180 deg rotated? Mine has the ribbon coming out of the top edge, as most I have seen seem to, and the backlight LED is to the right of the display when the ribbon is uppermost.

I'll give that newer firmware you've built a whirl, thanks. Out of interest, how do I go about compiling my own? Additionally, could you send me the source of the flipped/working one which I referred to in my last post, since there seems to be one billion different variants, builds, modified versions etc... it's all a little confusing, hah!

Thanks yet again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 13, 2017, 12:38:53 am
Meanwhile I've got a few cheap and crappy RC servos for testing the servo check function. Based on them the best range for the pulse length seems to be 0.5 - 2.5 ms (instead of 1 - 2 ms). Do you got similar experience? I've also received some PCF8574 based LCD backpacks which work fine. The new m-firmware version will have a simple I2C framework supporting the ATmega's TWI and bit-bang I2C. So we can add more I2C clients. While investigating LCD backpacks I saw also some MCP23008 based ones. A good opportunity if you like to sponsor the m-firmware ;) Or do you got any other I2C wishes?

Hi Markus, this is a great news  :-+

Regarding the servo check function, AFAIK the center position should be for a pulse width of 1.5ms, the lowest and highest value varies for each servo.
The cheap servo checker available on ebay has 3 functions:
- center
  It provide a signal with 1.5ms pulse width every 20ms. This is very useful setting up the RC models
- manual
  Rotating the knob it provide the signal depending by the position of the knob from 1 to 2 ms
- Auto
  It sweep between the min and max pulse width continuously from 1 to 2 ms

Mauro
Title: Compiler help needed
Post by: avrishuvorlaz on February 13, 2017, 05:58:32 am
Please read - I wish to help with the development of this product.

I am experienced with Linux, Windows & macOS, I have no problem understanding concepts such as "$PATH", "ls", I am VERY much a command line person in regards to Unix OS' specifically.

Okay, I have Windows 7 and I have installed WINAVR, and I have also gone to:

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) and clicked "Download GNU tarball" - I have it downloaded and extracted with 7-zip etc...

#1 I know what a "Makefile" is, in essence, but...
#2 Once unarchived, which DIR do I go into, and which file do I edit for my customisations, please?
#3 From which folder do I run "make", once I have edited my "Makefile", and saved it, from the above?

If you'd give me a "starters guide" (I tried searching this thread, it's a NIGHTMARE to find what I need!) I would very much appreciate it, and can then start helping people. I am a VERY fast learner, I just need a "kick start" guide to what DIR, what commands etc - I know how to flash the firmware etc, it's just the configurations I need explained to me, and how to "make".

WINAVR is in my "PATH" by the way, so that's all setup as default.

Thanks so much! :)


<UPDATE>

I think I've worked it out:

Say I want to edit the options and compile the firmware for the "mega328_T3_T4_st7565" variant, I simply:

1/ Go to where that folder is, in my case "C:\Users\Myname\Desktop\transistortester-trunk.tar\transistortester-trunk\trunk\mega328_T3_T4_st7565" and edit the "Makefile" for the options I want.

2/ Open  a CMD window in that "C:\Users\Myname\Desktop\transistortester-trunk.tar\transistortester-trunk\trunk\mega328_T3_T4_st7565" DIR, and run "make" ... right?

3/ Flash the freshly built .eep and .hex into my T4 and test, rinse and repeat until it works as desired.



Ah, once I had worked that out, I went to: https://github.com/svn2github/transistortester/tree/master/Software/trunk (https://github.com/svn2github/transistortester/tree/master/Software/trunk)

... and read:

This directory contains the program source for all TransistorTester versions.
To build the programming files for your ATmega microcontroller
please change to one of the following subdirectories:
mega8, default, mega328, mega168_strip_grid, mega328_strip_grid, mega328_dogm and mega328_strip_grid_dogm

The mega8 subdirectory contains the Makefile to build the programming data for a ATmega8 microcontroller.
The default subdirectory contains the Makefile to build the programming data for a ATmega168 controller.
The mega328 subdirectory contains the Makefile to build the programming data for a ATmega328 controller.
The subdirectories with the _strip_grid ending contains the Makefiles for the different connection
of the LCD used for the strip grid board and can not be used with the normal connection of the LCD.
You can find the programming data and the matching Makefile for the DOGM style LCD in the subdirectories
with dogm ending (mega328_dogm and mega328_strip_grid_dogm).

All subdirectories hold the Makefile the compiled data TransistorTester.hex and TransistorTester.eep!
The .hex data must be loaded to the flash memory and the .eep data must be loaded to the EEprom memory.
With the Linux operating system or with WinAVR the data can be loaded with the program avrdude to the
memory of the ATmega, controled with the Makefile. The connected ISP programmer must be supported by the program avrdude.
The data can also be loaded with any other program to the ATmega without control of the Makefile.

You can also create a own subdirectory and copy any of the Makefiles of the other directories to this
own subdirectory. Now you can set other options in this Makefile copy in your directory and try to build
your own TransistorTester programming data in this directory.

Please tell me, if you have problems with my software or if you have found errors.
You can send me a Email to kh_kuebbeler@web.de or answer to my www.mikrocontroller.net (http://www.mikrocontroller.net) thread.

Good luck
Karl-Heinz Kübbeler


So it seems I was on the right track?


I did a test "make" from the folder named above, and also saw the "107%" error for the main .hex, which was mentioned elsewhere due to inefficiencies in a new(?) toolchain, etc, as seen here:

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-9/16708437_10155029909112937_1227650508477908531_n.jpg?oh=9e08e59cf32a1dacf9aeff8639c84844&oe=5908CE63)

How do I fix that? Clearly I can't fit 107% of something into 100% of program space, hah! :P


I saw "AVR Studio" mentioned somewhere - I take it that is not a pre-requisite? Not a problem if it is, but I get a hunch it's not needed.

See, I am a fast learner! :P

Cheers for your assistance, take it easy, I'll come back in about 10 hours or so. Sleep time now... zzzzzz
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on February 13, 2017, 06:13:27 am
Madcat,
i have a bag of n-mosfets i puchased from ebay that show as double diodes and that is bcause they are  :(
there are all sort of fake components out there so be careful.
Before start testing unknown components make sure you test a set of known good components.  :)
Title: Re: Compiler help needed
Post by: timelessbeing on February 13, 2017, 07:41:51 am
I tried searching this thread, it's a NIGHTMARE to find what I need!

I should remind everybody, if you are responding to a post immediately before (or even a ¡few before) yours, there is no need to 'Quote' their entire post. This makes the forum more difficult to read. Especially, when a post three pages long and full of pictures, gets quoted over and over again. Please use 'Reply' instead. Also if you're responding to just one particular sentence, you can trim out everything else.

(I realize that one of the problems is that the reply button is only at the top and bottom of the page. On other forums I've seen it conveniently placed at the end of each post. I think I might mention it to the mods.)
Title: Re: Compiler help needed
Post by: timelessbeing on February 13, 2017, 08:01:14 am
So it seems I was on the right track?

I did a test "make" from the folder named above, and also saw the "107%" error for the main .hex

I think you are on the right track.

Where did you get your toolchain? What is your compiler version?

The oversized hex files has been brought up a few times. It's always caused by one of two problems. Either the wrong format (Intel) is being specified to AVRDUDE. I don't think that's your case since you're using a makefile. Yes, the other cause is using the wrong version of compiler (AVR-GCC). The solution that people suggested was either using an older version, or using the one included with the Arduino IDE (free one, not AVR Studio). I have been using the latest build (6.2.0) without problem. Since you are familiar with Linux, try cloning the 'gcc-avr' repository.

Here's a link with details (http://maxembedded.com/2015/06/setting-up-avr-gcc-toolchain-on-linux-and-mac-os-x/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 13, 2017, 10:44:57 am
Hi Mauro!

Regarding the servo check function, AFAIK the center position should be for a pulse width of 1.5ms, the lowest and highest value varies for each servo.
The cheap servo checker available on ebay has 3 functions:
- center
  It provide a signal with 1.5ms pulse width every 20ms. This is very useful setting up the RC models
- manual
  Rotating the knob it provide the signal depending by the position of the knob from 1 to 2 ms
- Auto
  It sweep between the min and max pulse width continuously from 1 to 2 ms

At the moment the servo check starts with a 1.5ms pulse and you can turn the rotary encoder to change the pulse length down to 0.5ms or up to 2.5ms. A short button press resets the pulse back to 1.5ms. Of course the pulse length is displayed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 13, 2017, 01:33:39 pm
That should be more than enough and actually better than the cheap servo tester, since you'll know the position of the motor for each value of the puse width  :-+
Anyway a better servo tester should support analog and digital servo:

50Hz   analog servo                   signal period 20ms
125Hz digital for steering gear   signal period 8ms
250Hz digital servo                    signal period 4ms

On some hobby model forums I read someone complaining on the min/max pulse width that should be within 800-2200uS to avoid damage on some servo, but do not quote me on this.

I know the purpose of this ESR/LCR/transistor tester..... is changing a bit, but since we are adding something useful let's do it at best!!! :)

Also the Auto sweep is important because you can test the speed responce of the servo, changing the sweep time.

Mauro
Title: Re: Compiler help needed
Post by: imidis on February 13, 2017, 02:20:15 pm

See, I am a fast learner! :P

Cheers for your assistance, take it easy, I'll come back in about 10 hours or so. Sleep time now... zzzzzz
Thank you for making me laugh!   :)

As someone else said, switching tool chains works for that. I used on linux the one that comes with the arduino ide, on windows too. Works much better size wise. Then the fun begins tweaking and playing!
Title: Re: Compiler help needed
Post by: avrishuvorlaz on February 13, 2017, 10:54:16 pm
I tried searching this thread, it's a NIGHTMARE to find what I need!

I should remind everybody, if you are responding to a post immediately before (or even a ¡few before) yours, there is no need to 'Quote' their entire post. This makes the forum more difficult to read. Especially, when a post three pages long and full of pictures, gets quoted over and over again. Please use 'Reply' instead. Also if you're responding to just one particular sentence, you can trim out everything else.

(I realize that one of the problems is that the reply button is only at the top and bottom of the page. On other forums I've seen it conveniently placed at the end of each post. I think I might mention it to the mods.)

Yes, it was around 6-7am and I was about to go to bed, so pedantically picking apart quote tags wasn't at the forefront of my mind, and thanks for reminding me, it is annoying when people do this - I hold my hands up!
Title: Re: Compiler help needed
Post by: avrishuvorlaz on February 13, 2017, 11:01:39 pm
So it seems I was on the right track?

I did a test "make" from the folder named above, and also saw the "107%" error for the main .hex

I think you are on the right track.

Where did you get your toolchain? What is your compiler version?

The oversized hex files has been brought up a few times. It's always caused by one of two problems. Either the wrong format (Intel) is being specified to AVRDUDE. I don't think that's your case since you're using a makefile. Yes, the other cause is using the wrong version of compiler (AVR-GCC). The solution that people suggested was either using an older version, or using the one included with the Arduino IDE (free one, not AVR Studio). I have been using the latest build (6.2.0) without problem. Since you are familiar with Linux, try cloning the 'gcc-avr' repository.

Here's a link with details (http://maxembedded.com/2015/06/setting-up-avr-gcc-toolchain-on-linux-and-mac-os-x/).

Okay, I am using Windows 10 right now, and have added Arduino IDE's bin to my path, and "avr-gcc" works fine from any location, but where is "make" - is that part of Arduino IDE, or will I have to install WinAVR too? (I know WinAVR adds all binaries to my PATH environment, as it should.)

I never quite know what is encompassed under "toolchain" when people refer to it; does "toolchain" include "make" executables too, because if Arduino IDE contains a "toolchain" (well I know it contains "avr-gcc.exe" etc) then it doesn't appear to include "make.exe".

~{EDITED}~

Okay, I managed to find a suitable "make.exe" copy @ ftp://ftp.equation.com/make/32/make.exe - I put it on my Desktop for the moment, to test it, and added that location to my PATH - it now builds fine, at only 93.2% program space :)

Thank you :)
Title: Re: Compiler help needed
Post by: imidis on February 13, 2017, 11:20:02 pm

Okay, I managed to find a suitable "make.exe" copy @ ftp://ftp.equation.com/make/32/make.exe - I put it on my Desktop for the moment, to test it, and added that location to my PATH - it now builds fine, at only 93.2% program space :)


I have installed WinAVR on my windows system then I just reference the arduino avr-gcc in the path within the makefile, alternatively you can add it in environment variables on the windows system.

Title: Re: $20 LCR ESR Transistor checker project
Post by: avrishuvorlaz on February 14, 2017, 01:32:23 am
Mr hapless, master of LCR firmwares, [...]

Heh, that's very kind of you, but there are people around here who are much more deserving of the title...

[...] I used your "TransistorTester (as above, but no flipping).zip" on my device which was originally on the "Mtester" firmware, and it works a treat... but one thing I have noticed is this - the characters seem to be shifted too far to the right by 0.5-1 characters - do you know how I would resolve this? The typeface is nice and bold - maybe a little TOO bold, at the expense of the chars flowing off the right hand side of the LCD.

The fonts are monospaced, so it's the width of the characters that matters, otherwise bold ones can be the same width as the thin ones. It's more of a matter of taste. As madires pointed out, the problem is with the offset that was deliberately used so that the exact same issue would be fixed for devices that have their screens rotated 180 degrees. I'm attaching a build that should fix this for you, but it doesn't use the exact same Makefile, so please let me know if I accidentally broke something.

Note: I made some (very few) slight changes to the output of the code. They are not even worth mentioning, but don't be surprised if you see that "Version1.13" now has a space in it or that "4 * ->|-" shows as "4 x ->|-".

[...]
i have brushed it with IPA, top&bottom side of it, and have some progress after that.   :-+
[...]
maybe my tester is still not work normally?

I'm very happy that it's finally starting to work, but you need to need to give it at least one more go with water (try to dry it as quickly as possible!) and then alcohol. Clean very thoroughly. You'll probably also want to clean between the pins of the MCU, too (just in case). Just make sure it's completely dry before powering up the board, and, of course, be gentle enough not to damage anything while you're at it.

You've fixed the "falling off the right-hand edge" issue, thank you!

(Attached as ZIP): As a nitpicker, I have edited some of the rather vague parts of the menu, in "Transistortester.h" - I didn't like the menu being called "Selection:" - "Main Menu:" looks far better in my opinion. I have also called the function generator "Square Wave Func Gen" as it describes it more precisely, and I have reduced the typeface to the lowest size - it really didn't need to be all that big, unless your eyesight is poor. I am just playing around with my new toy. :) - please have a play with it.

I've now permanently soldered a header on my tester for my USBASP, whereas before I was just holding it onto the pads firmly with one hand, whilst typing with the other. Because the solder side of the header pins (I soldered the header so it stick out of the BACK side of the PCB, obviously) fouls the light diffuser at the back of the LCD, I have raise the LCD module up around 3-4mm with some self-adhesive foam pads.

Sorry to the pedants, I can't work out who is which quote, so I just clicked "quote" - it's not my job to fix bugs or missing features in forum functionality, you'll have to forgive and put up with quotes of quotes of quotes until someone rectifies this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 14, 2017, 07:22:05 am
@vrishuvorlaz I wasn't picking on you. It's just something I noticed in general, and you provided a good opportunity to bring it up, since you were complaining about being able to find information. Quoting something that was said on a previous page, as you just did, is justified because that's exactly what it's for. But don't defend laziness or blame somebody else, because it's inexcusable. There's no bug. If you are replying to the most recent post, then the reply button is right under your nose. No scrolling required. I'm not pedantic, I simply think we should be courteous to all the other users of the forum who might need help, like you. I don't think think this needs further explaining.

EDIT: Do you see the new 'Reply' button there next to 'Quote'. Dave liked the idea and added it.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 14, 2017, 07:33:56 pm
+1 for the newly added and handy reply link. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: avrishuvorlaz on February 15, 2017, 03:21:33 am
@vrishuvorlaz I wasn't picking on you. It's just something I noticed in general, and you provided a good opportunity to bring it up, since you were complaining about being able to find information. Quoting something that was said on a previous page, as you just did, is justified because that's exactly what it's for. But don't defend laziness or blame somebody else, because it's inexcusable. There's no bug. If you are replying to the most recent post, then the reply button is right under your nose. No scrolling required. I'm not pedantic, I simply think we should be courteous to all the other users of the forum who might need help, like you. I don't think think this needs further explaining.

EDIT: Do you see the new 'Reply' button there next to 'Quote'. Dave liked the idea and added it.  :-+

 Thank you, I understand - I couldn't work out which was which quote ID - I *REALLY* dislike messy quotes. Finally Dave has added a per-message "reply" button, that's nice yes, what took so long? It's a basic forum feature, shouldn't be seen as some miraculous "upgrade".  :-//

Let's say Dave were reviewing V 0.1 of a PSU board, and it didn't have enough spacing between live and neutral and VERY thin traces, and then a week later he was sent a fixed version with those issues resolved, I wouldn't expect him to congratulate the designer - it was inevitable that this should be fixed; same applies to the "reply" button. But anyway, thanks Dave - finally - I shall thank you - certainly better late than not at all. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: avrishuvorlaz on February 15, 2017, 03:59:08 am
Thankfully the maker of my LCR-T4 tester had the good sense to mark the ISP port for programming - the legend is UNDER the LCD, you just need to de-solder the LCD backlight LED and lift... and you see it. I've also taken a photo of the LCD ribbon cable on my model, for what it matters - it may help someone:

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-0/s480x480/16602981_10155035368312937_3449018022215142594_n.jpg?oh=82e8534d5fb7ec4cf548e04cd0ffb228&oe=593034B4)

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-9/16708292_10155035368412937_5288216375682011198_n.jpg?oh=839a019200606fee00c857aacbb2217d&oe=59033DA0)

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-9/16729414_10155035368377937_8638236556260210213_n.jpg?oh=971226770214825db0b4c00b099de610&oe=59027AD6)

Out of interest, how does one find out what type of LCD/driver chip/interface is used, per tester variant, please? Thanks.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 15, 2017, 06:01:34 pm
Anyway a better servo tester should support analog and digital servo:

50Hz   analog servo                   signal period 20ms
125Hz digital for steering gear   signal period 8ms
250Hz digital servo                    signal period 4ms

Ok, I've added those frequencies and also 333Hz for some high speed servos. The UI will be similar to the deluxe PWM generator.

Also the Auto sweep is important because you can test the speed responce of the servo, changing the sweep time.

Let's see if I'm able to find a way to add that too...
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 15, 2017, 06:25:18 pm
This is great!!!  :-+
I have few spare servo and ESC from my RC helicopters/multicopters secondary hobby ready to test the new firmware  :)
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on February 15, 2017, 07:40:53 pm
Thankfully the maker of my LCR-T4 tester had the good sense to mark the ISP port for programming - the legend is UNDER the LCD, you just need to de-solder the LCD backlight LED and lift... and you see it..
What is even nicer is that he made it so a standard socket can be attached to the back. Note that the labels you see on the top side are actually mirror image of a standard 6 pin ISP connector

Graham
Title: Re: $20 LCR ESR Transistor checker project
Post by: MickM on February 15, 2017, 10:25:42 pm
Hi;
  I have a Sarduino ( http://spaceagerobotics.com/blog/projects/sarduino/ (http://spaceagerobotics.com/blog/projects/sarduino/) ),
and a Sanguino (http://sanguino.wikidot.com/ (http://sanguino.wikidot.com/)) in my junk drawer.
( abandoned for 2560 Mega )

Basically just breakout boards for an ATmega644/1284.
I have built several testers based on the Atmega328, and want to expand it.
I would like to incorporate the various adapters, ( opto, options etc)
Is there up to date docs on this?
What else should I add?

Has anyone done this?, any hints?

Oh I also ordered one of these:
https://www.newegg.com/Product/Product.aspx?Item=9SIABV75251610&nm_mc=TEMC-RMA-Approvel&cm_mmc=TEMC-RMA-Approvel-_-Content-_-text-_- (https://www.newegg.com/Product/Product.aspx?Item=9SIABV75251610&nm_mc=TEMC-RMA-Approvel&cm_mmc=TEMC-RMA-Approvel-_-Content-_-text-_-)

It's a "IC Transistor Tester Detect Meter Maintenance Digital led Tester MOS PNP NPN "
It tests 74xx and 4xxx chips.

I watched this video, and went searching.
https://www.youtube.com/watch?v=vmL4bZlsFu0 (https://www.youtube.com/watch?v=vmL4bZlsFu0)

MickM

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: avrishuvorlaz on February 16, 2017, 03:34:33 am
Thankfully the maker of my LCR-T4 tester had the good sense to mark the ISP port for programming - the legend is UNDER the LCD, you just need to de-solder the LCD backlight LED and lift... and you see it..
What is even nicer is that he made it so a standard socket can be attached to the back. Note that the labels you see on the top side are actually mirror image of a standard 6 pin ISP connector

Graham

Yeah, it's very nice that it's a standard ISP layout, but then it would be no big deal if it wasn't.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 16, 2017, 10:53:34 am
Basically just breakout boards for an ATmega644/1284.
I have built several testers based on the Atmega328, and want to expand it.
I would like to incorporate the various adapters, ( opto, options etc)
Is there up to date docs on this?

Karl-Heinz' documentation would be the best place to start. It includes two circuits for the 644/1284 and most options. I'll attach the schematic of my 644/1284 dev board. The nice thing besides the additional I/O pins is that we can use hardware I2C and SPI. The pin assignment of the 328 based tester doesn't permit that. The basic pin assignment for the 644/1284 is:

Port A: ADC
- PA0: Probe #1
- PA1: Probe #2
- PA2: Probe #3
- PA3: V external (Zener)
- PA4: 2.5V reference
- PA5: V battery
- PA6: unused
- PA7: Probe for fixed 100nF cap for auto-adjustment

Port D: resistors and serial
- PD0: RXD0
- PD1: TXD0
- PD2: TP1 R_Low
- PD3: TP1 R_High
- PD4: TP2 R_Low
- PD5: TP2 R_High
- PD6: TP3 R_Low
- PD7: TP3 R_High

Port C: controls and I2C
- PC0: I2C (SCL)
- PC1: I2C (SDA)
- PC2:
  + frequency counter: 16:1 divider
  + parallel cap for SamplingADC
- PC3:
  + frequency counter: Input Select P0
  + rotary encoder A
- PC4:
  + frequency counter: Input Select P1
  + rotary encoder B
- PC5: Rh for fixed 100nF cap (auto-adjustment)
- PC6: power control
- PC7: push button

Port B: HD44780 display
- PB0: frequency counter: f in
- PB1: unused
- PB2: RS
- PB3: E
- PB4: D4
- PB5: D5
- PB6: D6
- PB7: D7

Port B: SPI display
- PB0: frequency counter: f in
- PB1: unused
- PB2: /Reset
- PB3: Data/Command
- PB4: /CS
- PB5: MOSI
- PB6: MISO
- PB7: SCK

There are also ideas to extend the B port with one or two 74HC595 for driving displays and other things.

It's a "IC Transistor Tester Detect Meter Maintenance Digital led Tester MOS PNP NPN "
It tests 74xx and 4xxx chips.

That's a completely different tester. Some do also a few OPamps and other ICs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2017, 04:46:49 pm
This is great!!!  :-+
I have few spare servo and ESC from my RC helicopters/multicopters secondary hobby ready to test the new firmware  :)

By using a second timer plus ISR I was able to add the sweep function. When in sweep mode the tester displays the sweep time (for sweeping the PWM pulse from 1ms to 2ms).
Title: Re: $20 LCR ESR Transistor checker project
Post by: MickM on February 17, 2017, 11:26:47 pm
Hi;
 Thank you Madires.
Yes I have the docs, but there seems to be lots of scattered tidbits, and adapters out there.
I will be using Eagle which has size limits.
So daughter boards it is, the port info is great.

The other tester is indeed  a different beast.
I have never seen a portable one, ( so cheap too ), and just thought that I would share it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 18, 2017, 04:55:00 am
Yep, the firmware measures the voltage at PC4 and if it's around 2.5V it assumes it's the external voltage reference. The pull-up resistor makes sure that PC4 is outside the expected voltage range, and 100k or 220k would be fine also. The m-firmware behaves the same way, but HW_REF25 (config.h) controls if the code get's included or not.
What is the procedure if not using the voltage reference, but relay extension is used? No pull-up resistor?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 18, 2017, 09:07:43 am
What is the procedure if not using the voltage reference, but relay extension is used? No pull-up resistor?

A pull-up resistor at PC4 (ATmega 328) and the BJT's base resistor should be replaced by a higher value. The MCU uses PC4 as input for measuring the reference voltage and as open collector output for switching the relay. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: mateusps on February 18, 2017, 01:43:19 pm
I'm having some trouble getting my AY-AT tester to work, it keeps displaying the message "Probing" "Battery? 1: 4996v" (using the Trendy 1.25 firmware) - The original chinese firmware was similar, but stuck in the 'short probes!' message. I've tried with another atmega328 but the result is the same :(
Any clues on how to fix this?

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 18, 2017, 02:36:55 pm
I'm having some trouble getting my AY-AT tester to work, it keeps displaying the message "Probing" "Battery? 1: 4996v" (using the Trendy 1.25 firmware) - The original chinese firmware was similar, but stuck in the 'short probes!' message. I've tried with another atmega328 but the result is the same :(
Any clues on how to fix this?

The tester tries to tell you that it measures 5V on probe pin #1 while it expects 0V. Possibly caused by some short.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mateusps on February 18, 2017, 06:50:34 pm
Hi madires,
I tried to power on the tester with the atmega pins relative to the test points 1/2/3 lifted. It still displaying "battery?" but now is around 1800mV
Even with this pins lifted and some components removed, 5v still preset on the TP 1.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Strada916 on February 18, 2017, 06:54:57 pm
You might want to take a photo showing the soldering

Sent from my D6503 using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 18, 2017, 07:10:43 pm
I tried to power on the tester with the atmega pins relative to the test points 1/2/3 lifted. It still displaying "battery?" but now is around 1800mV
Even with this pins lifted and some components removed, 5v still preset on the TP 1.

With the resistors for probe #1 removed and the MCU pins lifted you could check for any shorts. I'm not sure but the 1800mV might be ok when the MCU pin (PC0 for probe #1) is floating.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mateusps on February 18, 2017, 07:32:31 pm
Thanks madires! I'm still looking for shorts on the board.

@Strada916

I've posted hi res photos on imgur and a video

http://imgur.com/a/p5uXU (http://imgur.com/a/p5uXU)

https://www.youtube.com/watch?v=Vz7LN1SbkMs (https://www.youtube.com/watch?v=Vz7LN1SbkMs)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strada916 on February 18, 2017, 07:51:48 pm
Some of the joints need a little more solder. Otherwise it's ok.

Sent from my D6503 using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 19, 2017, 05:34:42 am
A pull-up resistor at PC4 (ATmega 328) and the BJT's base resistor should be replaced by a higher value. The MCU uses PC4 as input for measuring the reference voltage and as open collector output for switching the relay.

I used 22K for my base resistor. If I use 220K for the pull-up, that will allow 21uA to always flow to my BJT, which I think will turn it on a little bit. Can I use a higher value pull-up? Like 5 meg to make sure the transistor stays off when it's not needed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 19, 2017, 12:49:51 pm
I used 22K for my base resistor. If I use 220K for the pull-up, that will allow 21uA to always flow to my BJT, which I think will turn it on a little bit. Can I use a higher value pull-up? Like 5 meg to make sure the transistor stays off when it's not needed?

The relay is operated in reversed logic, i.e. the relay short circuits the probes when not switched on. For switching the relay you want to drive the BJT into saturation. Therefore the pull-up resistor plus the base resistor in series have to pass enough current to do that. At the same time you have to make sure that the voltage at the connection of both resistors (PC4) is not around 2.5V to prevent the tester from thinking it's an external 2.5V reference (k-firmware). And the pull-up resistor should be as high as possible to limit the current through the MCU when PC4 is switched to low.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 1413 on February 19, 2017, 09:51:47 pm
For those who have the same kit like mine, which is known as AY-AT kit, I fixed user interface here and there for best use with rotate encoder. Almost all functions leave untouched

- Based on version 1.26m
- Press down and hold -> menu
- When icon power on/off appears on bottom right corner, rotate left -> restart, rotate right -> menu, press button -> turn off
- Change Zener to Vext because this kit doesn't have the hardware to do it.
- If you want zener measurement, use external voltage
- Update makefile to work with USBtinyISP

Thanks madires for a wonderful job
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 20, 2017, 01:46:59 pm
I'm very happy that it's finally starting to work, but you need to need to give it at least one more go with water (try to dry it as quickly as possible!) and then alcohol. Clean very thoroughly. You'll probably also want to clean between the pins of the MCU, too (just in case). Just make sure it's completely dry before powering up the board, and, of course, be gentle enough not to damage anything while you're at it.
i'm not confident enough to clean it with water yet, especially with rotary encoder, zif&atmel socket, and DC jack is still soldered onboard. does it safe to do that (clean with water)?

Madcat,
i have a bag of n-mosfets i puchased from ebay that show as double diodes and that is bcause they are  :(
there are all sort of fake components out there so be careful.
Before start testing unknown components make sure you test a set of known good components.  :)
thank you for the information. i didn't know that those fake components exist in ebay. must be more aware when buy them next time.
but in my case, i think it is my tester which have false reading about the mosfets, because i've run some manual tests on them with DMM (refers to some youtube tutorials), my mosfets really are mosfets, not dual-diode, and they acts as they should in circuit.

is it possible that i have some customized firmware in my atmega chip that not functions normally as the original one?
or maybe i need to redo the soldering and clean each of the components from old flux residue that might unreachable when i cleaned them while still soldered onboard, like the bottom of zif&atmel sockets?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on February 21, 2017, 05:54:04 am
or maybe i need to redo the soldering and clean each of the components from old flux residue that might unreachable when i cleaned them while still soldered onboard, like the bottom of zif&atmel sockets?

If nothing else works, you may have to. But I would do so only as a last resort.

is it possible that i have some customized firmware in my atmega chip that not functions normally as the original one?

If you didn't flash it yourself, the answer is, "Who knows!" But I think in this case it's unlikely.

i'm not confident enough to clean it with water yet, especially with rotary encoder, zif&atmel socket, and DC jack is still soldered onboard. does it safe to do that (clean with water)?

I'm not telling you to put it into a bucket of water and leave it there overnight. Use a little on a toothbrush. Tap water is somewhat alkaline in most places. This will help neutralize the acid. Then you immediately clean the same spot with alcohol. I have not had any electronic components rust on me just yet after this.

I never quite know what is encompassed under "toolchain" when people refer to it; does "toolchain" include "make" executables too, because if Arduino IDE contains a "toolchain" (well I know it contains "avr-gcc.exe" etc) then it doesn't appear to include "make.exe".

That's because it's different for different projects. For our purposes, the default definition of a toolchain would probably be whatever Atmel thinks it is.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on February 22, 2017, 03:12:57 pm
after did 3-passes of IPA "bath", brushed it with toothbrush concentrated at bottom of zif&atmel sockets body, i think my tester is working normally now! yeaahhh!
now it able to detect mosfets&transistors correctly, quite precise at capacitor, resistor&voltage measurements.  :-+

thank you to all who helped me solved my problem. this community is awesome!   :clap:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on February 22, 2017, 10:47:16 pm
For those who have the same kit like mine, which is known as AY-AT kit, I fixed user interface here and there for best use with rotate encoder. Almost all functions leave untouched

- Based on version 1.26m
- Press down and hold -> menu
- When icon power on/off appears on bottom right corner, rotate left -> restart, rotate right -> menu, press button -> turn off
- Change Zener to Vext because this kit doesn't have the hardware to do it.
- If you want zener measurement, use external voltage
- Update makefile to work with USBtinyISP

Thanks madires for a wonderful job

Hi 1413,
Can you post the compiled files please.
8 and or 16 Mhz.
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 23, 2017, 08:20:47 pm
Please find 1.27m in the SVN. Besides several smaller improvements the new version has an alternative PWM gen for testers with a rotary encoder, a servo checker and support for PCF8574 based LCD packpacks. The I2C framework allows to add other I2C clients quite easily. BTW, I've dropped the edition name, so it's just 1.27m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 24, 2017, 03:03:11 pm
Hi Markus I just compiled the 1.27m for my M12684 DIY Kit and noticed something strange on the Servo test function:
If I select 50Hz sweep mode I see on the display:
Servo
*2944ms
  50Hz <->

I don't have a servo connected, but looking at the output signal is doing some sweep...
If I turn the rotary encoder slowly of one step, the sweep speed jumps to 89.21ms, if I go back up it reach 2944ms after some random increments.
I guess the firmware is trying to change the sweep speed dividing it in half, in half again and so on, but looks like it jumps alot.
M'I wrong?

Within next Monday I should perform some tests with the morors I have and will give you some feedback.
Thank you so much

BTW, I tryed also the Opto Coupler test function ant it is really cool!!

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 24, 2017, 03:42:39 pm
If I turn the rotary encoder slowly of one step, the sweep speed jumps to 89.21ms, if I go back up it reach 2944ms after some random increments.

The change should be related to the turning speed of the encoder. In extras.c in function Servo_Check() there's following code:
Code: [Select]
    /* consider rotary encoder's turning velocity */
    Step = 1;
    if (Enc.Velocity > 1)          /* larger step */
    {
      Step <<= Enc.Velocity;       /* 2^velocity */
    }

Enc.Velocity is in the range of 1 to 7 based on the turning speed. You could try to replace the code above with something like this:
Code: [Select]
   Step = Enc.Velocity;

Do you got that issue just with the servo check or also with other tests?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 25, 2017, 05:17:50 am
If anybody needs, Electronics Goldmine has some authentic TEXTOOL gold plated ZIF sockets for $2.
http://www.goldmine-elec-products.com/prodinfo.asp?number=G22009 (http://www.goldmine-elec-products.com/prodinfo.asp?number=G22009)
It's cam lock, rather than lever lock, which might work better for people who want enclosures.
(http://www.goldmine-elec-products.com/images/G22009B.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 25, 2017, 06:22:18 am
That cam lock is pretty neat. I suppose one could 3D print a knob to fit in it for use in an enclosure.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 1413 on February 25, 2017, 10:59:37 am
For those who have the same kit like mine, which is known as AY-AT kit, I fixed user interface here and there for best use with rotate encoder. Almost all functions leave untouched

- Based on version 1.26m
- Press down and hold -> menu
- When icon power on/off appears on bottom right corner, rotate left -> restart, rotate right -> menu, press button -> turn off
- Change Zener to Vext because this kit doesn't have the hardware to do it.
- If you want zener measurement, use external voltage
- Update makefile to work with USBtinyISP

Thanks madires for a wonderful job

Hi 1413,
Can you post the compiled files please.
8 and or 16 Mhz.
Thanks.

Open readme.txt for how to compile in windows 10.
Anyway, I attach the compiled hex and epp files
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 25, 2017, 07:13:46 pm
Since the ST7735 isn't extremely slow, you could try and move the power-on section in LCD_Init() to the end. Maybe just LCD_Cmd(CMD_DISPLAY_ON), and removing MilliSleep(120).

Hi, madires!
Once again I want to thank you for excellent operation!
Would like to pay attention to some questions in operation of a firmware to AY-AT kit.
The display in case of start has a garbage. If to use your council which I quoted then this problem disappears.
I very much liked the fact that you offset symbols of elements on lateral face. It will allow to use a font with higher resolution for displays 128x64!
I used in case of compilation of a firmware symbols with permission 30x32.
It well looks on the display with permission 160x128.
One more request to you - whether add options will be involved in config.h which I marked on a screenshot?
Title: Re: $20 LCR ESR Transistor checker project
Post by: javagerms on February 25, 2017, 08:38:16 pm

i got the EZM LCR meter. but I'm puzzled.
the LCD pcb has 9 holes, but i got only 8 male pins connector.  on the main pcb, it has 9 female slots.
so should align on the left or to the right.
thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on February 25, 2017, 09:14:27 pm

pen readme.txt for how to compile in windows 10.
Anyway, I attach the compiled hex and epp files

Yes, you are right, I have to learn compiling myself,
but, very thanks for your great and usefull help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 26, 2017, 12:23:32 pm
One more request to you - whether add options will be involved in config.h which I marked on a screenshot?

I'll add a configuration switch for the ST7735 initialization. HW_ADJUST_CAP and  HW_CAP_RELAY are two hardware options for the ATmega 664/1284 based circuit. The first one is a fixed film cap plus 470k resistor for the adjustment procedure. And the latter is for connecting a fixed cap in parallel to the test pins when using SamplingADC. So you don't have to connect a cap manually. But both options aren't implemented yet in the m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: cfoek on February 26, 2017, 03:19:00 pm
Thankfully the maker of my LCR-T4 tester had the good sense to mark the ISP port for programming - the legend is UNDER the LCD, you just need to de-solder the LCD backlight LED and lift... and you see it. I've also taken a photo of the LCD ribbon cable on my model, for what it matters - it may help someone:

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-0/s480x480/16602981_10155035368312937_3449018022215142594_n.jpg?oh=82e8534d5fb7ec4cf548e04cd0ffb228&oe=593034B4)

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-9/16708292_10155035368412937_5288216375682011198_n.jpg?oh=839a019200606fee00c857aacbb2217d&oe=59033DA0)

(https://scontent-otp1-1.xx.fbcdn.net/v/t1.0-9/16729414_10155035368377937_8638236556260210213_n.jpg?oh=971226770214825db0b4c00b099de610&oe=59027AD6)

Out of interest, how does one find out what type of LCD/driver chip/interface is used, per tester variant, please? Thanks.

hello , I also bought this tester have you successful flashing the hex and epp files ?
mine flash successful use hex and epp from http://www (http://www) mikrocontroller net/ , but when i push the button display blank only with led turn on

if you successeful flash this tester what firmware did u use and what program did you use ?

oh i use sinaprog 2.1 with usbavr china clone 

thanks

Edit :
ups sorry did not read carefully on your post on previous page , i will try  on your firmware that u post (mega328_T3_T4_st7565_SmallerTypeface_Menu_edits)

will report back thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 26, 2017, 05:40:39 pm
In most cases it's some other LCD controller or the default contrast needs to be changed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: waspinator on February 26, 2017, 06:57:52 pm
has there been any effort to write an open source firmware for these type of modules?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 26, 2017, 07:22:36 pm
Both firmware versions (k & m) support a multitude of display controllers, all open source.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on February 27, 2017, 06:36:04 am
Hi, is there some sort of a detailed description of the differences/advantages/disadvantages between the k & M version of the firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 27, 2017, 11:25:01 am
Just a brief one in the m-firmware's readme file. It's an ever changing story ;) Maybe someone would like to create and maintain a comparison chart.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 28, 2017, 02:12:24 pm
Hi Markus,
    in this days I was a little busy, but I prepared the setup to verify the servo checker function.
As you can see in the attached pictures, I'm comparing the behaviour of the super cheap servo tester with the new function you implemented on the m firmware.

As you suspected I have the same issue also with the PWM and Square Wave function that are also implemented differently from the 1.25m (this was working fine with this 2 functions).

Changing  Step <<= Enc.Velocity; with Step = Enc.Velocity;  It helps a bit during the sweep mode, but It looks like there is something wrong in the evaluation of the rotation speed and no matter how I rotate slow or fast the encoder, it jumps a lot.
In manual mode each step of the encoder it change the "position" of 0.01ms and it is painful to use...

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 28, 2017, 05:32:48 pm
What type of rotary encoder do you got? With detents? How many Gray code pulses per detent or step?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 01, 2017, 01:45:51 pm
Hi! :)
If it is interesting to someone, then I added the schematic diagram for TC-1 clone.
On the diagram not all elements are designated and there can be small errors, excuse!
https://yadi.sk/d/wtrds6Nt3EaQXY
Several versions of the schematic diagram for Fish8840(Box) are also added
https://yadi.sk/d/DM5MA--L3E48as
All thanks to the participant of the Russian-speaking forum mr.sleska!
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 01, 2017, 01:53:38 pm
Hi Markus,
    my encoder is the standard one that comes with the Banggood DIY Kit:
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html?rmmds=detail-top-buytogether (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html?rmmds=detail-top-buytogether)
It has detents, with 20 steps/turn.

I connected a logic analizer to the PD1 and PD3 where the encoder is connected/configured and attached you can see the pulses I get for each step during a full rotation and for a single step.
As you can see for each step I got one pulse, than  the firmware send something to the display.

Just as a comparison I attached also the same acquisition for a full rotation of the encoder scrolling the menu on the k firmware.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 01, 2017, 03:48:25 pm
Mauro, could you please add a few lines of code to Servo_Check() in extras.c for debugging. Look for
Code: [Select]
      Flag &= ~UPDATE_PULSE;            /* clear flag */
    }

    /* PWM frequency/period */

and insert between "Flag &= ~UPDATE_PULSE;" and the curly bracket:

Code: [Select]
      Flag &= ~UPDATE_PULSE;            /* clear flag */
LCD_Space();
DisplayValue(Enc.Velocity, 0 , 0);
    }

That should display the rotary encoder's turning speed of the previous turn (1-7) behind the pulse length (or sweep time). 1 is slow and 7 is very fast. Which speed values do you get?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mateusps on March 01, 2017, 09:37:46 pm

The tester tries to tell you that it measures 5V on probe pin #1 while it expects 0V. Possibly caused by some short.

Finally found the short :phew:

https://youtu.be/4AN6rInz5s8?t=269

Title: Re: $20 LCR ESR Transistor checker project
Post by: Tech_JA on March 01, 2017, 10:14:39 pm
Great job!  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 02, 2017, 10:01:21 am
Hey mateusps,
     you should add some music to that video with a dramatic voice over and you will get a mini thriller, at least it wasn't the butler Mr.Bad Soder  :)
 Nice job finding the short  :-+


Markus:
   I added the Enc.Velocity and also the displayed Velocity jumps a lot. I get
1    moving the encoder one step at a time and waiting a second before the next step 
5-6 moving the encoder really slowly without pause

I also noticed that it jumps more going on one direction and a bit less in the other.

If you need I'll try to put toghether a video but not at the mateusps level :)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2017, 11:40:59 am
Ok, so we know now that there's an issue with the detection of the turning speed with that particular rotary encoder. What have you set for ENCODER_PULSES in config.h?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 02, 2017, 02:38:18 pm
#define ENCODER_PULSES   2

I tryed 1 but than it jumps scrolling the main menu.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2017, 06:16:50 pm
Could you please also try ENCODER_PULSES 4?
Title: Re: $20 LCR ESR Transistor checker project
Post by: asadullah mir on March 03, 2017, 02:28:28 pm
Hi Guys,   
I just found this thread and am very keen to build a tester for my lab. I have read past the first 15 pages and I am not sure which is the latest version correct to build. At 133 pages it is a long thread.  Can someone point me in the right direction, please?.  The full thread is too long to go through and I will probably miss the correct info/design.
I am familiar with MCS-51 I claim to be a pro there :P but know nothing about the AVR processor. :-[
I have a  "stamp board" with an "ATmega128" chip mounted on it and all the pins brought out including the  AVR programming header I also have a programmer for this board.
I will design/etch my own PCB for the circuitry ( using the stamp as a daughter board no sweat.

Will the Atmega128 at 16 MHz do? Is the 128  compatible with the 328 etc?

Thanks for any help.

73
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 03, 2017, 04:50:00 pm
The ATmega 128 isn't supported by the firmware yet and is has only a 2.56V bandgap reference. Please use a 328 or 664/1284. For the current circuit please see Karl-Heinz' documentation at https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf .
Title: Re: $20 LCR ESR Transistor checker project
Post by: asadullah mir on March 04, 2017, 03:08:56 pm
That is disappointing. I have no use for these two boards I have had for a while.
I wonder if some worthwhile project exists to make good use of.
I have worked with the 8051 family for a long time and (Zilog earlier)  now am in the process of switching most of my work to Cortex stm32F10x family, as well as switching to C.
I know nothing about the AVR family though I understand they are good stuff.
Title: Re: $20 LCR ESR Transistor checker project
Post by: asadullah mir on March 05, 2017, 01:58:15 pm
Ok, the first link may not be the same thing, but the second one sure sounds like it. I think. It's in German, but here's google's translation effort:

http://translate.google.ca/translate?sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&eotf=1&u=http%3A%2F%2Fwww.mikrocontroller.net%2Farticles%2FAVR-Transistortester (http://translate.google.ca/translate?sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&eotf=1&u=http%3A%2F%2Fwww.mikrocontroller.net%2Farticles%2FAVR-Transistortester)


I built one last week, the fun part was persuading an Arduino to do the job of an AVR programmer :)
Have you posted the code using the  arduino which I am hoping is based on the cortex? Would love to make a working copy.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on March 05, 2017, 02:05:14 pm
Sorry, it makes no sense to me to quote and reply to a message of 4 years ago.
It seems a lot better to me to try to send a PM to the original poster.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vidmo on March 05, 2017, 04:06:18 pm
So I just wanted to brag, that I changed LCD in T4 version (that I broke before, because of that ridicules ribbon cable...) I covered it in my new blog (http://www.hackit.pl/2017/03/transistor-tester_5.html). I had to change (and rebuild) firmware, because image was mirrored, but now it's fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 05, 2017, 04:23:33 pm
Hi, madires! I have a question on use of IR detector fixed.
In the config_328.h file there are such settings
* IR detector/decoder
 * - fixed module
 */#define IR_PORT PORTC/*port data register */
#define IR_DDR DDRC/*port data direction register */
#define IR_PIN PINC/*port input pins register */
#define IR_DATA PC6/*data signal */

I understand that it is settings for the ATMega324/644 processor?
If it is possible, then explain in more detail how to set up ports in these lines? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 05, 2017, 05:18:41 pm
The option for the fixed IR receiver module uses a dedicated pin instead of the probes/test pins. For example, if the IR module's data output would be connected to PB2, you would have to set:
Code: [Select]
#define IR_PORT          PORTB     /* port data register */
#define IR_DDR           DDRB      /* port data direction register */
#define IR_PIN           PINB      /* port input pins register */
#define IR_DATA          PB2       /* data signal */

The ATmega type doesn't matter. It could be also a 328. PC6 is just a placeholder. BTW, if someone got the clone with the fixed IR receiver module, I'd like to know which MCU pin is used for the data line.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 05, 2017, 06:58:33 pm
Madires, thanks for the response! I already gave the reference to the diagram of a clone TC-1 in the message #3303, i hope that it will help you
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 05, 2017, 08:43:48 pm
So it's PD3 then (that's where encoder often goes)  :(.

I don't have one of those, but just wanted to point out that, from the videos of the way it works, it looks to me like they are using an interrupt to jump to the IR measurement screen when signal is detected. Not a bad idea if they are able to reliably screen out false triggers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 05, 2017, 09:08:40 pm
No, different pin assignments for ATmega 328 and 324/644/1284 ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 05, 2017, 09:18:13 pm
Isn't PD3 still INT1 on 324?

If you're talking about encoder placement, I was talking about 328. If you were to use that same pin, it would have to be in put where encoders go now in kits.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 05, 2017, 09:41:15 pm
Yes, INT1 is PD3 on the 328 and 324/644/1284. But neither k nor m-firmware use interrupts for the rotary encoder. And the IR detector/decoder in the m-firmware also doesn't use a pin change interrupt. So they can use any I/O pins.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 05, 2017, 09:45:27 pm
And we're in agreement. I guess I just don't know how to make my point. Maybe I'll try to find the words again later.  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 06, 2017, 12:57:02 pm
Hi Markus,
    I tryed ENCODER_PULSES 4 and while the sweep mode is improved, the manual one is too slow an I need to rotate the encoder several times to reach the min/max rotation.
In this days I was too busy and didn't had time to look at the firmware by myself.
I'll try again in the following days.
BTW the basic functionality to test the servos are there and it is just a matter of twick it a bit to improve the user experience.

Thank you
       Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 06, 2017, 02:13:11 pm
Thanks for checking! So "ENCODER_PULSES 2" seems to be correct for your rotary encoder. The next step is to investigate why the turning speed is so high (function TestKey()).
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 06, 2017, 06:30:21 pm
Hi, which is the latest firmware version from here https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/) do I need for this tester?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 06, 2017, 08:08:17 pm
Are you sure about the GM328? The rotary encoder isn't enabled for mega328_GM328/. Maybe it's mega328_color_kit/.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 06, 2017, 08:12:13 pm
That looks like an AY-AT, no?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 06, 2017, 08:28:09 pm
Are you sure about the GM328? The rotary encoder isn't enabled for mega328_GM328/. Maybe it's mega328_color_kit/.

Sorry, I am not sure the correct "name" of the tester.  That was the description on an Aliexpress listing (it may be inaccurate) but the picture is of the actual tester I have.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 06, 2017, 08:38:38 pm
Take a look at the silkscreen on the PCB. If it's the "AY-AT", it'll have those letters somewhere on there (I don't recall exactly where). But from the photo it sure looks like it with the rotary encoder and screw terminals.
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on March 06, 2017, 08:42:17 pm
If it helps that's what mine looks like and I use the mega328_color_kit
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 06, 2017, 08:44:11 pm
Yes, it does say on the the PCB 2578AY-AT
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 06, 2017, 08:51:09 pm
Very good. Confirmed. As madires and imidis said, you can use the mega328_color_kit.

If you want a manual and schematics for it, see the following post:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg990421/#msg990421 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg990421/#msg990421)
Title: Re: $20 LCR ESR Transistor checker project
Post by: linux-works on March 09, 2017, 04:03:13 am
@upsss:

I just bought that one.

(https://c2.staticflickr.com/4/3853/32924123460_1a57bfdece_z.jpg)

here is the makefile diffs for that model; I built the firmware and it looks great ;)

(https://c1.staticflickr.com/1/587/32924239450_c38b454aaf_z.jpg)

also, here is the command to upload using the old adafruit usbisp dongle:

Code: [Select]
sudo avrdude -c usbtiny -B 1.0 -p m328p -P usb -U flash:w:./TransistorTester.hex:a -U eeprom:w:./TransistorTester.eep:a
Title: Re: $20 LCR ESR Transistor checker project
Post by: linux-works on March 09, 2017, 04:07:56 am
@upsss:

you soldered the zif socket in the wrong way ;(

the lever is supposed to be on the right side!

Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 09, 2017, 06:34:55 am
@linux-works, thanks but that is not an actual picture of my tester.  My original picture was from the website I bought my tester, they installed the socket wrong. 

I installed my socket the right way, I also added an ISP connector, Banana Jacks, replaced the crystal with 16MHz and I use a Li-Ion battery which I charged through the DC connector.
Title: Re: $20 LCR ESR Transistor checker project
Post by: linux-works on March 09, 2017, 12:49:15 pm
nice case!  so funny - I was wondering HOW to solve the lever problem with my own plastic case.

would you be willing to share the design files for that case?  I'm planning on making some for myself and friends on the local laser cutter at my hackerspace.

I like the opening you notched out, kind of, for the lever.

nice job!  good photo, too ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 09, 2017, 01:15:52 pm
My very first tester with the rotary encoder and frequency counter options:
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=297782;image)

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=297784;image)

Title: Re: $20 LCR ESR Transistor checker project
Post by: linux-works on March 09, 2017, 01:37:50 pm
we almost need a sub-forum for this topic ;)

would love to see what people have done for cases, for this.  I'm thinking of making some and still collecting ideas.

looks like the banana jack idea is popular so I will add that to my to-do list.  was also thinking of having it be Qi rechargeable via simple credit-card style adapters like these:

https://images-na.ssl-images-amazon.com/images/I/61V8AbhnLNL._SL1200_.jpg (https://images-na.ssl-images-amazon.com/images/I/61V8AbhnLNL._SL1200_.jpg)

you get a simple 5v out from the micro usb connector.  cut it off, tap into it and go into a TP4056 lipo charger board, then use any 3.7v lipo battery.  that's the charging side.

then, you need a step-up, such as this: https://www.amazon.com/Control-Converter-Module-Charger-0-9V-5V/dp/B01FDD3AYQ (https://www.amazon.com/Control-Converter-Module-Charger-0-9V-5V/dp/B01FDD3AYQ)

that will get you back to 5v from the lipo.  after that, you don't need the 5v regulator chip anymore in the circuit.

not sure how clean the psu output will be - might need some filtering.

put the Qi coil on the very bottom of the case and use thin plastic to cover it.  1/8" is ok but thinner is even better.  then you simply lay the box into a Qi cradle and that's the charging solution.  this cradle is nice since it lets you center the coil on the sender side:

https://www.amazon.com/gp/product/B0177SPJP8/ (https://www.amazon.com/gp/product/B0177SPJP8/)

it has a knob on the back that lets you raise/lower the coil, so once you build your coil rx into your box, you align the 2 coils with the knob on the stand.  it works pretty well and is good fun for DIY.

(https://images-na.ssl-images-amazon.com/images/I/41b2LKiCb8L.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 09, 2017, 04:38:59 pm
Great idea. I've made a new thread for enclosure and other physical mods and included upsss, madires, and pepe10000's recent case photos as examples to get started.

https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/ (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/)

Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 09, 2017, 04:56:39 pm
nice case!  so funny - I was wondering HOW to solve the lever problem with my own plastic case.

would you be willing to share the design files for that case?  I'm planning on making some for myself and friends on the local laser cutter at my hackerspace.

I like the opening you notched out, kind of, for the lever.

nice job!  good photo, too ;)

I didn't design the case, I bought it from Aliexpress.  Take a look at post 3069 this was my original tester which I built more than a year ago.  What I ended up doing there was bend the lever up.  As far as the LCR T4 tester, I never liked it, it doesn't work properly with a rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 09, 2017, 05:43:10 pm
@bitseeker, thanks for starting the new thread I too think it is a great idea.  I added already some more pictures. 

For some reason your link doesn't work properly.  I tried to add another link and it does the same thing, for some reason it goes to the top of the forum.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 09, 2017, 06:27:50 pm
Thanks, upsss. I fixed the link. It has to have a slash at the end of the URL to work properly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: IvoS on March 09, 2017, 08:56:20 pm
Hello, I just got my kit as well. Using AT328P chip and color display.
Could the firmware be burned as HEX file using this
http://www.ebay.com/itm/like/122355661168?lpid=82&chn=ps&ul_noapp=true (http://www.ebay.com/itm/like/122355661168?lpid=82&chn=ps&ul_noapp=true)
MiniPro programmer? Help is appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 09, 2017, 09:04:55 pm
Presumably yes. "AVR" indicates that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: IvoS on March 09, 2017, 09:29:59 pm
Actually, more accurate question would be how do I make the hex file out of the firmware files? Is there someone with MiniPro programmer willing to share a hex file (project file) for mega328P?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rrinker on March 10, 2017, 01:55:26 am
 Mine is like the last couple pictured, it came with an 8MHz crystal. What is involved with changing it to 16MHz? Swap the crystal and reflash the firmware with the proper fuse settings? Anything else need to be altered?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 10, 2017, 03:21:31 am
They all come with a standard 8MHz crystal.  All you have to do is replace the crystal with a 16MHz, edit the Makefile, compile and and reflash it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: linux-works on March 10, 2017, 05:44:20 am
I have a minipro but didn't use it.  I used an adafruit tinyisp, which is kind of old, but is really just an atmel style chip programmer.  you supply your own zif socket for that.

to answer your question, to convert the 'firmware files' to a hex file - that's called compiling.  you would have to install the 'tool chain' (gcc, and all the rest) to run 'make' and create the binary hex file.

if you already have hex, then you should be able to import it into minipro and burn as usual.  maybe I'll try that when I have time and see if there are any issues.
Title: Re: $20 LCR ESR Transistor checker project
Post by: StormJunkie on March 10, 2017, 10:53:38 am
Sure can't beat the price on this little tester.  Any advice on getting one?  Bangood? 
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 10, 2017, 11:17:21 am
Hello, I just got my kit as well. Using AT328P chip and color display.
Could the firmware be burned as HEX file using this
http://www.ebay.com/itm/like/122355661168?lpid=82&chn=ps&ul_noapp=true (http://www.ebay.com/itm/like/122355661168?lpid=82&chn=ps&ul_noapp=true)
MiniPro programmer? Help is appreciated.

I don't know your skills so do not be offended if I tell you something you already know:

Why you need to upgrade the firmware?
If you have just received the tester enjoy it. If it works do not rush on burning a new firmware.

If I got it correctly you have this tester:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=297098;image (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=297098;image)

This tester can be upgraded with 2 different firmwares the m-firmware and the k-firmware

For the k-firmware, each time a new version is released in the following folded you will find the files already compiled for your specific hardware:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/)

To load this firmware with your TL866 programmer on the ATmega328 you need to load the .HEX file as INTEL HEX in the Code memory, the .epp file as INTEL HEX in the Data memory and then you need to set the proper fuses as shown in the attached picture.

For the m-firmware (madires is the author of this amazing variant!!!), each time a new version is released in this folder you will find the updated sources.
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)

As stated by linux-works if you want to customize the k firmware enabling some optional functions or you want to try the m firmware you need to modify in the sources few files (Makefile and/or config.h...) and compile it with the proper tools.

Here you can fing a nice guide to build the firmware
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926)

Or look for the posts of tom666 in this thread, he posted so many usefull informations.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 10, 2017, 11:30:47 am
Sure can't beat the price on this little tester.  Any advice on getting one?  Bangood?

I like this variants:

My personal choise (the color one was not available and I like to have the tester in the case)
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html?rmmds=search (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html?rmmds=search)

This the current runner.
http://www.banggood.com/DIY-Mega328-Transistor-Tester-Kit-Capacitance-Inductance-ESR-Meter-Diode-Triode-With-Case-p-1129565.html?rmmds=search (http://www.banggood.com/DIY-Mega328-Transistor-Tester-Kit-Capacitance-Inductance-ESR-Meter-Diode-Triode-With-Case-p-1129565.html?rmmds=search)

I like also this
http://www.banggood.com/3_5inch-Colorful-Display-Multi-functional-TFT-Backlight-Transistor-Tester-p-1083042.html?rmmds=search (http://www.banggood.com/3_5inch-Colorful-Display-Multi-functional-TFT-Backlight-Transistor-Tester-p-1083042.html?rmmds=search)

Mauro

Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 10, 2017, 06:07:13 pm
Can't beat this price, $10 including shipping!  I got mine with an acrylic case for $15.

https://www.aliexpress.com/item/Multifunctional-Tester-GM328-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator/32781120613.html? (https://www.aliexpress.com/item/Multifunctional-Tester-GM328-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator/32781120613.html?)
Title: Re: $20 LCR ESR Transistor checker project
Post by: IvoS on March 10, 2017, 07:55:19 pm
Thank you "mauroh", you provided very useful information, I don't have to browse all 134 pages.
Many thanks. Thank you "linux-works" for the info as well.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rrinker on March 10, 2017, 08:54:09 pm
They all come with a standard 8MHz crystal.  All you have to do is replace the crystal with a 16MHz, edit the Makefile, compile and and reflash it.

 Perfect. I have everything I need but some spare 16Mhz crystals. Think I'll get a few spare ATMega328s too. Thanks.

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on March 11, 2017, 04:43:54 am
You can get like 10 crystals for less than $1 on eBay.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Melkocha on March 11, 2017, 01:50:32 pm
Hi Madires & Co.

I want to update my version 1.12 K in model T4 with your latest firmware.

Is it mature? (I know that never it is, but I mean if work well the functions that includes  ;)

What other features has built-in? (Test IR, servos,... what more?)

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 11, 2017, 02:54:22 pm
The m-firmware is mature since the first version ;) Let's see what else we got:
- dedicated optocoupler test
- CLDs
- MT1/MT2 detection for TRIACs
- FETs with low I_DSS
- less trouble with depletion mode FETs vs. Germanium BJTs with high leakage current
- two adjustment profiles
- support for 20MHz MCU clock
- bitbang & hardware I2C and SPI for displays

@Mauroh: I've ordered a bunch of the cheapest rotary encoders I could find, including EC11 fakes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Melkocha on March 11, 2017, 03:21:49 pm
The m-firmware is mature since the first version ;) Let's see what else we got:
- dedicated optocoupler test
- CLDs
- MT1/MT2 detection for TRIACs
- FETs with low I_DSS
- less trouble with depletion mode FETs vs. Germanium BJTs with high leakage current
- two adjustment profiles
- support for 20MHz MCU clock
- bitbang & hardware I2C and SPI for displays

Wow, thanks you Madires! Amazing work!

Is this firmware available for the hardware version T4?
Is it necessary to make any changes on the PC Board? (In this case, could you show the link?)
Did I read days ago about tests on servos? Are present?

Thanks again!

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 11, 2017, 03:34:42 pm
IIRC the settings for the T4 clone are listed in the "Clones" file. You don't have to mod your tester, unless you like to add some hardware options. The servo check was added in the last version (1.27m).
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on March 24, 2017, 03:19:58 pm
Hi.

I'm having some problems with the latest firmware revisions k (722 and 723) in measuring medium-low resistors value with my LCR-T4-H testers.

However with 729 and previous revisions work perfectly.

I attached some photos of the problem in question.

Is someone else going on?

Thank you and greetings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stevelup on March 24, 2017, 04:00:34 pm
Received mine today. It's the colour LCD version with encoder. I bought it with the laser-cut acrylic case.

£12 ish and just 13 days for delivery from Aliexpress. Impressed!

Will assemble it tomorrow. Intention is to test it as supplied, then swap the 8MHz crystal for a 16MHz one and load the latest firmware.

Title: Re: $20 LCR ESR Transistor checker project
Post by: linux-works on March 25, 2017, 09:53:56 pm
what is needed in order to power this directly from a 5v source?

I'm looking at the schematic for the m328 (graphical unit) and it has 3 transistors in the psu area.  I'm not 100% sure why they are all there, and if I should remove any or just direct wire my 5v supply to the output of the regulator chip and ignore everything before it (?)

I'm going to use a lipo 3.7v -> 5v step-up and don't have the option to supply 9v to the unit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 26, 2017, 08:03:29 am
The PNP switches the power (pass transistor), one NPN driven by the MCU is switching the pass transistor and the second NPN is the button feedback for the MCU. One way would be to replace the 5V regulator by the boost converter and adjust some resistor values in the power circuitry. And add a LC filter to the boost converter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 26, 2017, 08:06:21 am
These are great little testers.  I am looking for a DIY kit with M328, basic graphics LCD and rotary encoder, 2016 V1.12 software, and a PCB that has an ISP port so I can update it in the future.  Anybody recommend a decent seller ?

Plesae see the post just above your's ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pishta on March 27, 2017, 02:13:03 am
I just built the "EZM328 V1.10 '2016' model" based on the DIP Atmega 328 and was wondering if there was a firmware update to this model (FW says 1.12K). This one has the rotary encoder and the 3 prong probe plug in left side and no battery terminals on the bottom. Also has Frequency input/output (?) as a plug on upper right. It uses a 12864 9 pin green backlit (BL = pin 9) monochrome display, but they only gave me 8 header pins! They also shorted me 4 standoff screws.  Designer labeled as "EZM Electronic Studios" although it was never silk screened in white ink as mine was possibly a scrap board buyout as it has a silkscreen error on the board, showing 2 R1 resistor location call out (Its an R10 misprint). Works fine, but some other versions have better "graphics" for components.  They sent me the kit with no assembly instructions but directed me to this link for callouts. http://115.28.16.44:81/file/4660.pdf (http://115.28.16.44:81/file/4660.pdf)
(https://www.forabodiesonly.com/mopar/attachments/component_tester-page-001-jpg.1715032118/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 27, 2017, 08:45:11 am
The current k-firmware under development (1.13k) is available at https://github.com/svn2github/transistortester/tree/master/Software/trunk, Karl-Heinz' excellent documentation at https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf, and the m-firmware (1.27m) at https://github.com/svn2github/transistortester/tree/master/Software/Markus.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on March 27, 2017, 02:37:37 pm
The problem persists in firmware k revision 725.

It continues to measure impedance capacitance and frequency when you measure medium-low resistance value.

I return to the 719 revision that works perfect.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Experimenter on March 28, 2017, 11:17:37 am
Hi All,

I was looking for an ESR meter and found this thread. This is an excellent device, thanks to the continuous support of the developers!

My goal is to be able to check capacitors in the power supply circuits. These caps may be quite large at times (2700uF and larger). Is there a way to do it with this meter?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 28, 2017, 11:32:26 am
Should work fine. I've tested caps up to 20mF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Experimenter on March 28, 2017, 11:48:46 am
Oh, that's great!

Reading through the manual, it says it can measure up to 10mF, which should be plenty for my needs!

Thanks for confirming this!

Now, another question: has someone thought of building an SMD-components version of this one? Looking at Ebay / Aliexpress / Banggood offers, there seem to be already built versions available, but I couldn't find a setup that I like (I want a rotary encoder in there, and preferably an ISP header to be able to update the firmware easily). There are also kits available, but they come with through-hole components. I don't have anything against that, but I'm so used to SMD during the last few years that I am starting to think of building an SMD-components version myself...
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on March 28, 2017, 03:05:27 pm
There are many SMD Variants but it seems that they realized that people like the bigger components better for easier hackability.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Experimenter on March 28, 2017, 06:01:37 pm
Well, that explains why kits use through-hole components. On the other hand, SMD variants are cheaper to make (the components are cheaper)...

Anyway, I think I'll start with a kit (or a ready-made board) from China. And if I will miss some features, I'll work on my own PCB then.

Right now I'm debating between this kit: https://www.aliexpress.com/item/Multifunctional-Tester-GM328-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator/32781120613.html (https://www.aliexpress.com/item/Multifunctional-Tester-GM328-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator/32781120613.html)

And this pre-assembled board: https://www.aliexpress.com/item/LCD-GM328A-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator-SMT/32722907639.html (https://www.aliexpress.com/item/LCD-GM328A-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator-SMT/32722907639.html)

There's also a "newer" board (link updated!!!): https://www.aliexpress.com/item/2016-Top-Sale-Multifunctional-LCD-GM328B-Transistor-Tester-Diode-Capacitance-ESR-Frequency-Meter-Generator-PWM-Signal/32768594864.html (https://www.aliexpress.com/item/2016-Top-Sale-Multifunctional-LCD-GM328B-Transistor-Tester-Diode-Capacitance-ESR-Frequency-Meter-Generator-PWM-Signal/32768594864.html)
But it doesn't have the encoder (which I believe is a downside). And I'm not sure if it has any advantages over the previous two...
Title: Re: $20 LCR ESR Transistor checker project
Post by: stevelup on March 28, 2017, 06:25:23 pm
I bought from the same seller as your first link (along with the laser cut enclosure).

I can confirm that all the bits were there, and it worked first time.

I've since changed the crystal to a 16MHz one and loaded the latest firmware.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on March 28, 2017, 07:43:24 pm
@Experimenter
I believe the last link you gave is not the right one (link is the same as the previous one).

The use of an digital encoder makes the control of the device much more easier...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Experimenter on March 28, 2017, 08:52:46 pm
@Experimenter
I believe the last link you gave is not the right one (link is the same as the previous one).
Ooops! You're right, that was a copy-paste error. Sorry!
Link is updated.

The use of an digital encoder makes the control of the device much more easier...
Yeah, that's exactly why I want it! :)
I learned that on some other projects, and I find this thing really great for menu navigation and so on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 29, 2017, 09:15:54 am
I'm having some problems with the latest firmware revisions k (722, 723 and 725) in measuring medium-low resistors value with my LCR-T4-H testers.
However with 719 and previous revisions work perfectly.

Hi pepe10000,
I tried to replicate the issue with my M12864 kit, but on my tester I can’t see any difference.
The FW Ver. 725 works the same as the 719 regarding the resistance measure.

As far as I can tell from your pictures, you have a custom made enclosure (3d printed? nice BTW), possibly you are running wires from the PCB to the mini banana connectors and the tester is running on rechargeable  battery with a step up converter....
My guess is that the extra wires and/or the converter are messing up the measurements on the new version (slightly different).

Try removing the wires to the mini banana connectors (on the PCB side) and power it with a 9V battery

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on March 29, 2017, 10:24:57 am
Hi.

Thanks for the possible indications of the problem, but I have three units of this tester and the evidence indicates that the causation could be another.

In the second tester I tested I did not have DC-DC converters, it is powered by a rechargeable Ni-Mh battery and has no bananas.

I have also tested putting the resistance in different combinations 1-2, 2-3, 1-3 and the result is the same.

Attached photos of him.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: linux-works on March 30, 2017, 01:46:41 am
the rotary is not very useful, to be honest.  on graphic displays, at least, the screen refresh time is too slow.  up/down arrow buttons would be far superior to the rotary in THIS case.

Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 30, 2017, 05:17:15 am
I wouldn't say that. Monochrome displays don't really have that problem, and color displays can work slightly faster with an upgraded crystal. As for buttons in place of an encoder, IIRC firmware support for them is there. Just add them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: linux-works on March 30, 2017, 04:09:56 pm
close-ups of my Qi wireless charger build:

(https://c1.staticflickr.com/3/2949/32926764123_36eba2c195_b.jpg)

(https://c2.staticflickr.com/4/3948/32926756173_5d014bc7d0_b.jpg)

I divided the battery area in half; top half has this board (charger and up-verter to convert 3.7v to 5v)

https://www.amazon.com/gp/product/B00WDPQ8CE/ (https://www.amazon.com/gp/product/B00WDPQ8CE/)

bottom half of the compartment is where I have a quadcopter battery, 500mah, 3.7v.

the Qi charging coil is this item (but there are MANY like it; this one is just typical):

https://www.amazon.com/gp/product/B0199NI5XW (https://www.amazon.com/gp/product/B0199NI5XW)

cut off the micro-usb plug, find which connections are plus and minus and then just wire to the pads on the small charger pcb.  I removed the large usb port on the board since its not needed and just gets in the way; there are wires from that output to the place on the tester board that would get 5v from the regulator chip.


Title: Re: $20 LCR ESR Transistor checker project
Post by: ElectronicCat on March 31, 2017, 10:26:36 pm
I recently bought one of these on eBay as a kit as it was slightly cheaper and I thought it'd be fun to assemble. I finished assembling it the other day and tested it and everything seemed to work fine. Measured a few inductors and capacitors and they all read within the specified precision. However, when I picked it up again today and turned it on I noticed some weird glitches on the screen (See attached). I don't think it's the screen or dry joints as it appears to effect the same portion of text each time. I'm thinking ESD issue with the microcontroller? I can't exactly just reprogram it as it came pre-programmed without the source code. I've tried disconnecting the battery for some time but upon reconnecting and turning it on again it has the same issue. I've ran the display test program which shows it can display all the characters just fine, so I don't think there's an issue with the display itself. Anyone got any ideas?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 01, 2017, 12:03:41 am
Reprogram it. The source code is open, and precompiled versions are freely available, too. Nobody knows what the Chinese "manufacturers" flash into these things and how they do it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElectronicCat on April 01, 2017, 09:10:47 am
Reprogram it. The source code is open, and precompiled versions are freely available, too. Nobody knows what the Chinese "manufacturers" flash into these things and how they do it.
Any idea where I could get the source from? Also I'm assuming there's a bunch of different versions, as these come in various styles with different screens and features. I don't really want to brick it by flashing the wrong code only to have it not work with the hardware, and then not be able to find the original.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 01, 2017, 10:01:47 am
I've posted the links just one page back ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on April 01, 2017, 12:34:20 pm
You could of course also buy a spare Atmega CPU for a buck, that way you can keep the current (buggy) Chinese firmware.
Or ask the seller for a new one based on the corruption, sometimes they are very careful about their positive feedback...
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElectronicCat on April 01, 2017, 03:11:52 pm
I've posted the links just one page back ;)
Thanks, how do I identify which version I have? It's got an ATMega 328P, LCD is a JLX12864G-378 and the only other number seems to be on the PCB '1982-HS' and 'K132571BSJH'
You could of course also buy a spare Atmega CPU for a buck, that way you can keep the current (buggy) Chinese firmware.
Or ask the seller for a new one based on the corruption, sometimes they are very careful about their positive feedback...
Yea good call. I'm not sure I can be bothered to wait for a new one to arrive from China, I'll just order a new one so I can keep the old one if it doesn't work. Oddly I don't seem to have any spare DIP packaged 328s in my parts drawers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ebclr on April 01, 2017, 04:08:47 pm
A nice update

(http://avalandonline.net/ebay/images/EC6313/317757ef-a8b1-4445-ac35-917a6449c90e.JPG)

http://www.ebay.com/itm/LCR-TN-Multifunction-Tester-TC-V2-12k-TFT-Display-With-Electronic-Tweezers-/272561079648?hash=item3f75e80560:g:l7UAAOSw4A5YqGjb (http://www.ebay.com/itm/LCR-TN-Multifunction-Tester-TC-V2-12k-TFT-Display-With-Electronic-Tweezers-/272561079648?hash=item3f75e80560:g:l7UAAOSw4A5YqGjb)

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 01, 2017, 05:00:06 pm
Thanks, how do I identify which version I have? It's got an ATMega 328P, LCD is a JLX12864G-378 and the only other number seems to be on the PCB '1982-HS' and 'K132571BSJH'

I'd guess it's a ST7565. A picture of the tester (not just of the display) would help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 01, 2017, 05:10:26 pm
To ElectronicCat:
If I got it correctly you have this:

http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html?rmmds=search (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html?rmmds=search)

The sources and already compiled firmware are here
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)

Ciao
    Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElectronicCat on April 01, 2017, 06:28:43 pm
To ElectronicCat:
If I got it correctly you have this:

http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html?rmmds=search (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html?rmmds=search)

The sources and already compiled firmware are here
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)

Ciao
    Mauro
I'd guess it's a ST7565. A picture of the tester (not just of the display) would help.
I bought it from here (http://www.ebay.co.uk/itm/162259446114). Thanks Mauro, that looks like the one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on April 01, 2017, 06:44:52 pm
A nice update

(http://avalandonline.net/ebay/images/EC6313/317757ef-a8b1-4445-ac35-917a6449c90e.JPG)

http://www.ebay.com/itm/LCR-TN-Multifunction-Tester-TC-V2-12k-TFT-Display-With-Electronic-Tweezers-/272561079648?hash=item3f75e80560:g:l7UAAOSw4A5YqGjb (http://www.ebay.com/itm/LCR-TN-Multifunction-Tester-TC-V2-12k-TFT-Display-With-Electronic-Tweezers-/272561079648?hash=item3f75e80560:g:l7UAAOSw4A5YqGjb)

Here is a detailed review of this tester  https://www.youtube.com/watch?v=K-5zZfc1XkE (https://www.youtube.com/watch?v=K-5zZfc1XkE)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rrinker on April 03, 2017, 10:11:37 pm
 Question, before I attempt to upgrade my firmware. How do I tell which of the two color displays I have? The display panel itsel has no markings that are visible, and the only chips visible are a 4050 and an adjustable regulator, no controller/driver to be seen, without possibly prying off the LCD and polarizer. I'm assuming it won't actually hurt anything to just try one, and if it doesn't work, change the config file and try the other.
 My particular unit is one from KKmoon, got it through Amazon. It has the PWM output, frequency counter, and volt input. Works great except I have upgraded to a 16MHz crystal and while the resistor values are pretty spot on, all caps read 2x value and of course the output of the PWM is 2x what is selected - I pick 1MHz and my scope reads 2MHz. Exactly as expected. While I'm at it I figured I would try the latest firmware - I have some spare ATmegas328p's so I will leave the one it came with alone for now and burn a different one. I followed some links posted earlier in this thread and I'm pretty sure I have all the right options selected in the make and config files except for the LCD. The rest of my toolchain works, I've been messing around with ATTiny85's in addition to stock Arduinos and I was able to reset the fuses on the original chip to get it to boot under the 16MHz clock, just with the expected timing errors.

Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 04, 2017, 12:49:55 am
If no one identifies it from the description given, photos are helpful.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on April 04, 2017, 09:14:49 am
If the unit is this one (it is marked on the pcb: AY-AT):
https://www.amazon.com/KKmoon-MRH1631426738275XW-Multifunctional-Transistor-Capacitance/dp/B01HCXG9YS/ref=pd_sbs_469_t_2?_encoding=UTF8&psc=1&refRID=GNM9Z55C9HEKWVJ5RCJ7 (https://www.amazon.com/KKmoon-MRH1631426738275XW-Multifunctional-Transistor-Capacitance/dp/B01HCXG9YS/ref=pd_sbs_469_t_2?_encoding=UTF8&psc=1&refRID=GNM9Z55C9HEKWVJ5RCJ7)

you can use the ready made firmware of STJ:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1093923/#msg1093923

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 04, 2017, 10:30:30 am
The most common color display used by clones is the ST7735 (128x160) or something compatible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElectronicCat on April 04, 2017, 05:41:30 pm
Bit of an update. I received the blank ATMega 328 today and programmed it with the precompiled st7565_kit firmware. Stuck it in the transistor tester and it turns on, the LED works and the display backlight comes on but it doesn't display any information. I tried the other st7565 versions from the repository, st765, T5_st7565 and T3_T4_st7565 but they all had pretty much the same result. After sticking the original factory programmed IC back in it still works, albeit with the corrupted display data. Anyone got any ideas?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 04, 2017, 06:23:34 pm
Have you also programmed the EEPROM?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElectronicCat on April 04, 2017, 07:41:28 pm
Have you also programmed the EEPROM?
D'oh, I just noticed I forgot to include it in the avrdude command. Just flashed with the ST7565_kit firmware and the display works now, although it takes a few seconds to come on, and it seems to only measure capacitors (off by a factor of 10). It doesn't seem to detect anything else and the rotary encoder doesn't seem to work very well. As soon as I manage to get into the menu it seems to turn itself off. I'll try with the other ST7565 firmware for now, unless anyone has any ideas?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 04, 2017, 07:44:17 pm
Erm... Have you set the fuses?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElectronicCat on April 04, 2017, 08:26:53 pm
Do they have to be set to anything in particular? I think avrdude said something about setting them automatically and I said 'yes'. Command I'm using is avrdude -P /dev/ttyUSB0 -b 19200 -c avrisp -p atmega328 -U flash:w:TransistorTester.hex -U eeprom:w:TransistorTester.eep. Also got back from testing all the firmware again, st7565_kit is the only one that give any kind of screen output.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 04, 2017, 11:10:19 pm
At the very least, the clock needs to be redirected from internal to quartz (and its speed set according to the crystal's frequency). Try adding this to the command:
-U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0xfc:m

Note: I'm pretty sure that this is safe to do. Still... Use at your own risk, and check that these values don't disable SPI programming or the RESET line. Not responsible for bricked MCUs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rrinker on April 05, 2017, 12:03:37 am
 Yes, you can do just the fuses - that's what I did to the 328 that came with my tester after I swapped the 8MHz crystal for a 16MHz. It wouldn't boot, I set JUST the fuses, then it would boot but naturally all cap values were off by x2 as was the output of the function gen feature.

 Rather than make 2 posts - I just installed the K firmware for my AY-AT model using the 16MHz files. I have 2 brand new 328s, first one took the Flash and EEPROM no problem, but it just would not accept the efuse setting of 0xFC. So I tried the second one - same deal. Flash writes and verifies, EEPROM writes and verifies, but it will not accept efuse 0xFC. The one that came with my tester had no problem setting efuse. A little investigation says some 328's seem picky about setting bits that aren't actually used (maybe fakes? Maybe mine are fake?). The ACTUAL fuse setting when you use 0xFC is 0x04, so I set it to 0x04, it took that. First one, I got the whole screen to light up when pressing the encoder but it wouldn't start. The second one - success. Booted up, warned that it was not calibrated, etc. Ran through the cal (the original one wanted a 1000nF, this one asks for a 100nF). Kept showing the 100nF as 59nF. But resistors were right on, and other caps like a 220uF were within tolerance. I checked more ot the 100nF's in the bag - all came up 58 or 59nF. Double You Tee Eff? I don't have any others besides an assortment of ceramics and an assortment of electrolytics - testing a few others and they were fairly close, probably within tolerance. Then I remember, the BM235 DOES have a cap tester. So I tested one of these supposed 104's - it read 59nF. So what I really have are some dodgy as capacitors. Guess that'll learn me to buy cheap Chinese assortment sets. I tried a few at random and they generally match the marked value within tolerance, just this 104's are ALL way low.
 Checked the function gen - up to the 400 and change KHz setting it's dead on per my scope, and only slightly off on the higher ones. 50, 60, and 100 are 50.00, 60.00, and 100.00. So it is the right firmware for a 16MHz crystal. Guess I need to get myself some fairly precision caps of the right values to truly calibrate it. Resistors are dead on, it detected the proper Vf for an LED I tossed on, and had no problem with an NPN BJT or an IRF540 N channel MOSFET. Looks like I have a winner. And it probably was ok with an 8MHz clock with the original firmware as well, it's those joke caps that were leading me astray.

Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 05, 2017, 03:07:29 am
Well, at least now you know you can have some confidence in the tester. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: tomas1808 on April 05, 2017, 04:03:29 am
I am thinking about making/buying one of these.

Which chinese model is considered best and/or easy to mod to original specs?

Or should I just make my own tester using the official schematic?

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 05, 2017, 04:37:15 am
How much research have you done on this? :horse: Just curious.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElectronicCat on April 05, 2017, 08:49:04 am
Ok, I've set just the fuse values and that seemed to fix it. The extended calibration caught me out a bit and I had to dig around for the specified capacitor values but got them eventually, and then after calibration it seemed to work fine again. Thanks for the help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rrinker on April 05, 2017, 01:56:39 pm
Well, at least now you know you can have some confidence in the tester. :-+

At least for resistors and capacitors. I don't have a proper transistor tester to see if the values it is giving me are accurate, but it clearly can properly distinguish types at least. I guess this means back over to the TEA thread and start looking for a transistor tester - there may be a new acronym to add to the list too, something about having at least two of everything to validate the results, and even better, three so there is a tie breaker.  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 05, 2017, 02:04:57 pm
I know what you mean. I've got more Transistor Testers than scopes. It's such a pleasure to see them all agreeing on a component :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 05, 2017, 06:05:53 pm
I guess this means back over to the TEA thread and start looking for a transistor tester - there may be a new acronym to add to the list too, something about having at least two of everything to validate the results, and even better, three so there is a tie breaker.  :-DD

DEEP, DMM, and TEST (https://www.eevblog.com/forum/chat/test-equipment-anonymous-(tea)-group-therapy-thread/) are related afflictions, but don't specifically define use cases. So, you might have a bit of any of them. :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: tomas1808 on April 06, 2017, 12:29:49 am
Quote
How much research have you done on this? :horse: Just curious.

Enough to conclude that asking would be the best way to go. I've searched for certain keywords on the print version of this thread but got nothing. It would take much less time building the thing than reading a thread the size of a small book.

I guess I was wrong about the asking part.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 06, 2017, 12:52:00 am
Tomas, the AY-AT model is one of the latest and probably most feature complete version. But it depends if you need all that. Hence, there is no single best choice for everyone.

Start reading from this post forward:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1156384/#msg1156384 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1156384/#msg1156384)

It's significantly less than a book and will give you some recommendations from which to make a choice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tomas1808 on April 06, 2017, 02:29:29 am
Thanks bitseeker, that's exactly what I was looking for.

I'm still considering making my own though. I will share my design if I manage to do it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Housedad on April 06, 2017, 04:44:23 pm
so I finally got my bench, test gear, and spare parts together and went to the bench last night to play.   First thing was to take the tester (an AY-AT) and try it out on some of the Chinese spare parts to see how good/bad they were.  I have a wall wart for the power and proceeded to plug it in.   Screen lights up, dims, and the smell of blue smoke is in the air.  I quickly unplugged it, but it was too late.   I had plugged in the wrong wall wart.  It was 12VAC.  It fried the 10uf Cap which shorted the first 9012 transistor, cooking it.  I used the Microscope to see the 9012 and cap had micro bubbles on the surface.  Naked eye would never have seen it. Dmm showed shorts.  Desoldered, replaced, put the right wall wart into it, (12vDC) and it powered right up. 

I would never have guessed that the first thing I would do at that bench would be to fix my own mistake!
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 06, 2017, 06:06:36 pm
Well, Housedad, now that that's out of the way, onward and upward! :-/O
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 06, 2017, 11:20:12 pm
Well, if I had eyes rolling around naked on my new bench, I'd probably mix up my power supplies, too.   :D But if there's a danger of this happening again (and with two small power supplies that can plug into the same jack, there usually is), I would carefully break the trace from the positive lead of the socket and solder in a diode. Just in case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Housedad on April 07, 2017, 12:50:45 am
Good Idea.  I think I will do that soon.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on April 07, 2017, 02:19:26 am
I color code all my wall wart connectors with colored zip ties and put a zip-tie style cable marker with the voltage on them at the cable end.   I use a matching colored marker pen on or near the device power jacks.  It's way to easy to screw things up when you have 5/6/9/12/19/24/48 volt wall warts with 2.1mm barrel plugs on them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on April 07, 2017, 06:18:10 am
hi,
i just bought some blank atmega328p chips to try 16mhz crystal upgrade on the AY-AT model.
does the chip programming can be done on arduino uno board with usbasp programmer?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 07, 2017, 08:40:33 am
You can use the Arduino as ISP programmer (there's a sketch for that included in the IDE) with avrdude. usbasp is also an ISP programmer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElectronicCat on April 07, 2017, 08:43:52 am
hi,
i just bought some blank atmega328p chips to try 16mhz crystal upgrade on the AY-AT model.
does the chip programming can be done on arduino uno board with usbasp programmer?
Do you mean using the Arduino as the programmer (using ArduinoISP sketch) and a breadboard or using a USBasp programmer on an arduino with a blank chip? The former is definitely possible, but you'll need a crystal oscillator set up at the same frequency on the breadboard or wherever you program it. The latter I think should also work, provided the crystal is the same frequency but I've never tried it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 07, 2017, 08:45:13 am
If I got it correctly, since the tester don't have an ICSP connector...
Yes, you can sit the Atmega in an Arduino and use the usbasp connected to the ICSP connector to flash the firmware.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 07, 2017, 10:16:20 am
Thanks bitseeker, that's exactly what I was looking for.

I'm still considering making my own though. I will share my design if I manage to do it.

The current hardware design is available assembled and as DIY Kit for less than 10$...
If you really want to design your own, consider at least to use a bigger microcontroller.

The current firmwares M and K are using almost all the resources of the Atmega328p and with all the option enabled you will run out of flash and/or GPIOs.

The current firmwares supports already the Atmega644 and I think madires is working on a Atmega1284 hardware (looking forward for that!!).

Since I like all the options that require additional hardware like IR decoder, Zener Tester, tachometer, SuperCAP Tester.... I was thinking to use an ArduinoMega2560 board and build a custom shield with a color LCD and all the hardware to support all the firmware option.

Or alternatively design a ESP32-WROOM-32 based board.
It has a lot of horse power, bluetooth, WiFi and enough GPIO to connect all possible hardware options   :)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on April 07, 2017, 10:31:07 am
sorry for not being clear.  :)

yes, Mauro got my question right.
i mean put the blank atmega328p chip on arduino uno, and program it using usbasp.
if i remember correctly, arduino uno board also has 16mhz crystal onboard, though i don't really know if it has relevancy in programming process or not.

thank you all.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: linux-works on April 07, 2017, 02:03:06 pm
I'm hoping that this project can get ported over to the 'blue pill' ARM board.  those are now like $5 each or less and they have 128k of flash, plus 10 12-bit a/d ports!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 07, 2017, 03:55:09 pm
The problem with another MCU family is Vcc. We need 5V! For a MCU running at 3.3V or so we would have to add external switching, i.e. for each test resistor and probe pin. That would also imply an external ADC, unless the internal one supports voltages above Vcc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 07, 2017, 06:11:29 pm
Since I like all the options that require additional hardware like IR decoder, Zener Tester, tachometer, SuperCAP Tester.... I was thinking to use an ArduinoMega2560 board and build a custom shield with a color LCD and all the hardware to support all the firmware option.

Yes! I was thinking the same thing, a shield for the Arduino Mega 2560. I have one ready to become a host to such a shield. And a 3.5" color LCD shield to go on top.

Quote
Or alternatively design a ESP32-WROOM-32 based board.
It has a lot of horse power, bluetooth, WiFi and enough GPIO to connect all possible hardware options   :)

Isn't that only 3.3V?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 07, 2017, 07:07:42 pm
Yes, 3.3V only but I love it.
Didn't know that was an issue, I'll read the documentation...
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: ebclr on April 09, 2017, 01:15:12 am
In fact 3.3V can be nice, because will force to use a driver, and a high voltage driver with 10 / 20 vcc range will permit a new range of components to be tested, or even better a variable voltage driver

Title: Re: $20 LCR ESR Transistor checker project
Post by: qu1ck on April 09, 2017, 01:58:00 am
I believe I made the perfect tester for me.
The banggood m328 kit for $18 that comes with the case is pretty good, it even comes with 0.1% measurement resistors unlike some other kits. I just wasn't happy with their included front panel. Why waste a perfectly functional zif panel?
Also I wanted to get rid of the 9v power and use li-ion battery pack instead.
Here is the result:
http://imgur.com/a/39QZE (http://imgur.com/a/39QZE)
I forgot one modification on the picture. The resistor between 9012 base and power led anode, 3.3k one should be replaced with 1k. This is needed to keep the 9012 base current at 2-3ma. Without it I had significant voltage drop across emitter-collector.
Also put some capacitance on the step-up module input as seen on the pictures, I used 100uF. It is not needed if you use high frequency converter IC, but mine seems to be 2.5khz and without that cap voltage on the collector of 9012 was sagging slightly every time the mosfet of the boost converter was on.

The 2mm banana jacks are also a nice addon.

The precompiled firmware 1.13k with lower battery cut-off (3.1v) can be found here along with avrdude command and modified makefile http://s000.tinyupload.com/?file_id=01021722150636328454 (http://s000.tinyupload.com/?file_id=01021722150636328454)
Title: Re: $20 LCR ESR Transistor checker project
Post by: steffenmauch on April 09, 2017, 09:57:57 am
Can someone tell me what the limiting factor regarding measuring lower inductance is?
Thus, measuring 1uH e.g.

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 09, 2017, 10:37:50 am
In fact 3.3V can be nice, because will force to use a driver, and a high voltage driver with 10 / 20 vcc range will permit a new range of components to be tested, or even better a variable voltage driver

Higher and variable voltages and currents would be great to check more components and to measure more parameters. The downside is that the circuit would grow significantly and the firmware too. The current simple circuit hits the sweet spot of cost, simplicity and functionality. I don't have any idea if there will be some kind of Tester+ in the future. For the moment we concentrate on the classic ATmega 328 and the 644/1284s.

BTW (m-firmware), I've reworked the velocity sensing for the rotary encoder and added a way to finetune it. Right now I'm adding support for up/down push buttons as alternative to a rotary encoder, possibly with a speed-up function similar to the encoder's turning velocity.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 09, 2017, 10:55:24 am
Can someone tell me what the limiting factor regarding measuring lower inductance is?
Thus, measuring 1uH e.g.

The limiting factors for the inductance measurement are time resolution and current, which allow measurements down to about 10µH. The sampling ADC method (LC tank) can measure down to 100nH or so.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ebclr on April 09, 2017, 06:29:30 pm
while people have time and resources to do this

https://www.youtube.com/watch?v=5ax89hl4bz4 (https://www.youtube.com/watch?v=5ax89hl4bz4)


People,  Time and resource to do a tester + will appear, I am very interested in port the tester to ESP32, but need some help from other  people who share the same goal
Title: Re: $20 LCR ESR Transistor checker project
Post by: rrinker on April 09, 2017, 09:42:00 pm
hi,
i just bought some blank atmega328p chips to try 16mhz crystal upgrade on the AY-AT model.
does the chip programming can be done on arduino uno board with usbasp programmer?
Do you mean using the Arduino as the programmer (using ArduinoISP sketch) and a breadboard or using a USBasp programmer on an arduino with a blank chip? The former is definitely possible, but you'll need a crystal oscillator set up at the same frequency on the breadboard or wherever you program it. The latter I think should also work, provided the crystal is the same frequency but I've never tried it.

 Yes, this works quite well actually. I was doing some stuff with ATTiny85's so I built a shield witht he circuit on it and a socket for the 8 pin MCUs, but I also used it to load new firmware on the ATMega 328P for my tester, just ran some wires over to a breadboard, and plugged in a 16MHz crystal with a pair of 22pF caps. The Arduino as ISP sketch to load on the Uno is included in the IDE. You can then use the Arduino IDE to load code into the downstream micro, or if you have object files you can just push them with Avrdude. I cheated and used AvrdudeSS to use the GUO to control it. For a programmer you actually pick AVRISP and by default it operated at 19200 bps. The sketch even has allowances to set up some indicator LEDs, which I did with my shield, there's a heartbeat LED, a programming LED to show data flow, and an error LED to indicate a problem.

Title: Re: $20 LCR ESR Transistor checker project
Post by: macinblack on April 10, 2017, 10:52:10 am
Hi guys, I want to buy one cheap LCR until 20€, it this LCR (LCR-T1) the best: https://goo.gl/w7WKWQ (https://goo.gl/w7WKWQ) ? Thanks  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 10, 2017, 12:12:53 pm
That was answered one page back ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ebclr on April 10, 2017, 10:00:43 pm
Same but cheaper free shipping

https://pt.aliexpress.com/item/2017-LCR-TC1-Transistor-Tester-TFT-Diode-Triode-Capacitance-Meter-LCR-ESR-NPN-PNP-MOSFET/32783823366.html?spm=2114.02010208.3.2.q2CArZ&ws_ab_test=searchweb0_0,searchweb201602_2_10152_10065_10151_10068_10136_10137_10060_10138_10062_10153_10141_10056_10055_10054_10059_124_10099_10103_10102_10096_10148_10147_10052_10053_10142_10107_10050_10143_10051_10084_10083_10080_10082_10081_10110_10111_10112_10113_10114_10037_10032_10078_10079_10077_10073_10070_10123_10124,searchweb201603_6,afswitch_1,ppcSwitch_5&btsid=a8e89a6c-7ba4-4ef5-a037-7814472ec88a&algo_expid=150ba60d-b0b9-40e4-91ea-7d4eb476716d-0&algo_pvid=150ba60d-b0b9-40e4-91ea-7d4eb476716d
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 11, 2017, 01:12:42 pm
It is awesome!!
I tested the servo function on the m-firmware by madires...
It is possible to increase the pulse width by 0.01ms for each step of the rotary encoder  :-+

Just for fun I speed up an old HDD at 10200RPM with an ESC connected to the Transistor Tester and measured the speed with a laser-oscilloscope tachometer  :popcorn:

Thank you Markus for the great job (hope you don't mind I mentioned in the video description, If you prefer I can change it).

Mauro

https://www.youtube.com/watch?v=Ao8sUe7O9Ts (https://www.youtube.com/watch?v=Ao8sUe7O9Ts)

https://www.youtube.com/watch?v=c8YGUXi89fI (https://www.youtube.com/watch?v=c8YGUXi89fI)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 11, 2017, 08:36:03 pm
I've just released 1.28m. Highlights:
- Russian
- rotary encoder's velocity sensing reworked
- support of fixed cap for self-adjustment
- increase/decrease push buttons as alternative for rotary encoder (including speed-up functionality)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on April 11, 2017, 08:53:33 pm
I've just released 1.28m. Highlights:
- Russian
- rotary encoder's velocity sensing reworked
- support of fixed cap for self-adjustment
- increase/decrease push buttons as alternative for rotary encoder (including speed-up functionality)

Tested on an LCR-T4-H and all O.K.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: macinblack on April 11, 2017, 10:39:49 pm
That was answered one page back ;)

Thanks, I ordered one. Where can I find the last firmware? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 12, 2017, 03:34:04 am
I've just released 1.28m. Highlights:
- Russian

Windows-1251 with no conversion table for 1602, cemented inside a font?  :o  :-//

BTW, what tool was used to create the fonts originally?
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on April 12, 2017, 07:30:18 am
I got the AY-AT version of the tester. It came with the 1.12K firmware version.
I was able to program the 1.13K version using the HEX and EEP files downloaded from the software repository.
Next I wanted to try the 1.27m version but I couldn't compile anything on my windows 10 computer using WinAvr. I tried FlyWheelz instructions but they didn't work. I gave up and used a Windows 7 32 bit computer where I had all the software but hadn't used for a long time. I was able to modify the K code and compile it successfully but it was creating very big code that wouldn't fit on the Atmega 328P.
After more reading and searches on the internet I downloaded Cygwin (64 bit in my case), installed on the windows 10 machine and modified the computer path to include the cygwin64\bin folder. I was able to compile without any problems :) and most of the code generated fits on the microcontroller. Finally I was able to compile the 1.27m firmware and today the 1.28m for the AY-AT board.
I found some discrepancies with the different firmware versions:
I like how the K versions show more information when testing components such as transistors. Is it possible to modify the m version to include that information?
The m version code is more organized and easier to follow.
When testing a PN4117A the only firmware that shows correct information is on the m versions. At least from version 1.25m and up ( I haven't tested older versions)
The 1.12K version thinks that is a double diode. The 1.13K version thinks that is a transistor. The 1.28m version thinks that is an N-channel JFET with Idss=75ua. I know that Marcus code can detect JFETs with very low Idss. :)
 I also have a Peak DCA75 and it detect the part as a double diode. :( I haven't contacted them to see if they can modify the code to recognize the JFETs with low Idss.
Thank you to Markus and Karl for continuing the work of Markus Frejek and for being so available to help the comunity. :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on April 12, 2017, 07:49:42 am
The repository of the software is here:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2017, 09:13:24 am
And there's a mirror on github: https://github.com/svn2github/transistortester
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2017, 09:37:11 am
Windows-1251 with no conversion table for 1602, cemented inside a font?  :o  :-//

BTW, what tool was used to create the fonts originally?

Be my guest ;) Neither do I speak Russian nor do I have a HD44780 compatible LCD with a Russian font. If someone sends me a font_HD44780_cyrillic.h I'll happily add it to the source. I don't know which tool was used to create the 8x16 Cyrillic font. Maybe indman got an idea.

PS: I can provide a tool (linux) to convert bitmap fonts between different alignments and bit orders.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 12, 2017, 09:51:53 am
I can't find the link to the website with the archive pictures of most Transistor Tester variants....
The current firmware reporitory and mirror use a folder name that sometimes is difficult to match with the actual hardware specially when all the clone manufacturer use the same name for totally different hardware.

es:
Hardware                   
M12864 AKA Bangood DIY Kit         -> Folder name mega328_st7565_kit

AY-AT AKA DIY Color kit, GM328...-> Folder name mega328_color_kit

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2017, 10:13:03 am
I like how the K versions show more information when testing components such as transistors. Is it possible to modify the m version to include that information?

Basically yes. It's open source ;) Code and suggestions are welcome!

Quote
The m version code is more organized and easier to follow.

Sorry, my fault. ;D

Quote
When testing a PN4117A the only firmware that shows correct information is on the m versions. At least from version 1.25m and up ( I haven't tested older versions)
The 1.12K version thinks that is a double diode. The 1.13K version thinks that is a transistor. The 1.28m version thinks that is an N-channel JFET with Idss=75ua. I know that Marcus code can detect JFETs with very low Idss. :)
 I also have a Peak DCA75 and it detect the part as a double diode. :( I haven't contacted them to see if they can modify the code to recognize the JFETs with low Idss.

Wow! I had no idea that even the commercial product got a problem with that. Low I_DSS JFETs are supported since 1.24m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2017, 10:18:01 am
I can't find the link to the website with the archive pictures of most Transistor Tester variants....
The current firmware reporitory and mirror use a folder name that sometimes is difficult to match with the actual hardware specially when all the clone manufacturer use the same name for totally different hardware.

Do you mean https://yadi.sk/d/yW8xa5NJgUo5z ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 12, 2017, 02:32:18 pm
Windows-1251 with no conversion table for 1602, cemented inside a font?  :o  :-//

BTW, what tool was used to create the fonts originally?

Be my guest ;) Neither do I speak Russian nor do I have a HD44780 compatible LCD with a Russian font. If someone sends me a font_HD44780_cyrillic.h I'll happily add it to the source. I don't know which tool was used to create the 8x16 Cyrillic font. Maybe indman got an idea.

PS: I can provide a tool (linux) to convert bitmap fonts between different alignments and bit orders.

It just so happens that I have recently acquired one such device. They are a little on the expensive side where I live.

I don't really care about the origins of the Russian font. I was talking about a tool to create and edit the original fonts that are included. I don't normally work with fonts, so to view and edit them, I just manually decode and encode the data. But that's not a good idea for editing multiple glyphs. Any tool would be better than doing it by hand. I'm OS-agnostic, but allergic to multiple libraries that go out of date and fail to compile as soon as kernel gets updated...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2017, 03:46:56 pm
An internet search for "MCU font editor" lists several free editors ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 12, 2017, 03:50:51 pm
Yep. Each of which has its own idea of how to present its output. That's why my question still stands: Which one did you use?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2017, 04:05:45 pm
GLCD Font Creator
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 12, 2017, 04:12:11 pm
Thank you. I'll see what I can come up with.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on April 12, 2017, 06:37:29 pm
Testing the PN4117A with the AY-AT tester
1.- PN4117A JFET with 1.28m firmware
2.-PN4117A JFET with 1.12K firmware
3.-PN4117A JFET with 1.13K firmware
4.- PN4117A JFET with DCA75 from PeakElec
5.- PN4117A Data Sheet
In this case the only test that got it right is the m firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on April 12, 2017, 07:04:42 pm
Testing 2N7000 with the AY-AT tester
1.- 2N7000 with 1.28m firmware
2.- 2N7000 with 1.12K firmware
3.- 2N7000 with 1.13K firmware
4.- 2N7000 Data Sheet
In this case the 1.28m firmware doesn't show the diode between Drain and Source.
Added the compiled code for the AY-AT version.

Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 12, 2017, 08:29:07 pm
Your picture shows that it detects a diode. Look at the end of the "123" line. Or are you saying that you expected it to be drawn connected to the MOSFET?
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on April 12, 2017, 09:42:12 pm
Yes, I see that and the diode forward voltage as well but it would be nice to show the right symbol  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on April 13, 2017, 02:42:17 am
Interesting. It looks like you can use a junction FET as a low gain transistor - I had never thought of trying that.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=307697)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 13, 2017, 03:15:46 am
Be my guest ;) Neither do I speak Russian nor do I have a HD44780 compatible LCD with a Russian font. If someone sends me a font_HD44780_cyrillic.h I'll happily add it to the source. I don't know which tool was used to create the 8x16 Cyrillic font. Maybe indman got an idea.

PS: I can provide a tool (linux) to convert bitmap fonts between different alignments and bit orders.

Check out the attachment. I also included a slightly different translation; whether it is better or worse than what was there before, I don't know. I just used this as a sanity check to see that the text changes on the screen when changed within that file. Feel free to discard it if you want. If some characters are incorrectly mapped, I'd be happy to fix that.

The LUT took me by surprise though: Why are you not mapping it the other way around? The way it's done, only the first part of a large font can be used. No Unicode.  :'( I'll dig a little further into the code to maybe get the answer. Meanwhile, this was a nice little diversion for the evening. Will work on "real" fonts later in the week, hopefully. That's when that tool you were talking about may come in handy.

P.S.: The file is saved with Unicode + BOM encoding. Only comments make use of this. If it is a problem, feel free to save it in any other encoding. That shouldn't break any functionality. I can also rework the comments to contain only Latin/ASCII symbols, if need be. Just let me know.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 13, 2017, 11:19:10 am
Thanks for the Cyrillic LUT! I've choosen that design to keep the font data, i.e. the bitmaps for graphic LCDs, as small as possible while being able to use a standard character set in the source. Most 8 bit character sets keep the ASCII part and add the additional characters in the upper address space. The HD44780's international font has a lot of ISO 8859-1 characters but not the same addressing. Old versions of the firmware had to use "wrong" characters for German umlauts to match the HD44780's character set. And there are also the custom characters/symbols in the lower address space. While adding support for graphic LCDs the LUT solved three problems :)

BTW, in case someone wants to add another European language with special characters, please add the special characters to the LUT in  font_HD44780_int.h. At the moment it only includes ASCII and German umlauts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mek on April 20, 2017, 08:43:50 pm
post internal foto's

you need to replace the atmel with hot air and obviously program the replacement.
This is it. But even if I manage to replace the atmel, I cannot seem to find the program to flash. This Chinese clone of transistortester is not mentioned in the docs. Am I missing something?
Hey, I am back. I scourged the new pages of this topic to see if anybody encountered this Chinese clone but was surprised that I am still the only one :-[
I now have a new atmega328 (sadly, only in PDIP package as SMD is unavailable around here), however, my concern is that the HW of this clone is customized for the LCD and not compatible with the open source software. The LCD only has 12 contacts on flex cable and is marked "LX-12864TS Z". AFAIK, the other documented graphical LCDs have 14 contacts. This LCD is pretty much unknown to google, no docs, nothing.
The clone is made by fish8840 but all clones when I search for it, look totally different than mine.
So now I am not sure what to do (to reiterate: the original AVR is probably fried as cause of charged capacitor testing and now the tester measures wrong values). Maybe I could replace whole PCB and DIY a new one, reusing only the LCD and use PDIP atmega328.
Does this LCD sound familiar to anyone?
Also, I would like to try downloading existing firmware from the original AVR, to see if it is possible that the protection fuse bits would not be set. I was able to connect via ISP connector but unfortunately, the stupid auto-off functionality turns the chip off before I can do anything. Can I force it on somehow?

//edit: attaching pictures
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gino_09 on April 20, 2017, 09:20:17 pm
Hi all I' new (newbie). I have gm328 with tft/lcd color display. I have try last firmware but I not see colored symbol or lines. Have cristal 8 MHz. Do I have to modify make file? Which is the correct firmware?  Thanks and congratulation for the great work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on April 21, 2017, 12:00:54 am
Gino,
Please post pictures of your tester. There are many color display versions :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: qu1ck on April 21, 2017, 05:40:39 am
Mek

I can see on the pictures that there are 2 more wires aside from the ribbon cable that go to the LCD and the red one has marking LED. I'll bet it's just backlight power and your screen is same as 14 pin variants.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gino_09 on April 21, 2017, 05:52:52 am
@casinada

I'have this model
http://www.ebay.it/sch/i.html?&_from=R40&_trksid=p4712.m570.l1313.TR0.TRC0.H0.TRS0&_nkw=122312989617 (http://www.ebay.it/sch/i.html?&_from=R40&_trksid=p4712.m570.l1313.TR0.TRC0.H0.TRS0&_nkw=122312989617)
i can set only back and front color .......

Another question
i set fuse 0xff 0xd9 0x04 it's correct?

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on April 21, 2017, 06:39:52 am
@casinada

I'have this model
http://www.ebay.it/sch/i.html?&_from=R40&_trksid=p4712.m570.l1313.TR0.TRC0.H0.TRS0&_nkw=122312989617 (http://www.ebay.it/sch/i.html?&_from=R40&_trksid=p4712.m570.l1313.TR0.TRC0.H0.TRS0&_nkw=122312989617)
i can set only back and front color .......

Another question
i set fuse 0xff 0xd9 0x04 it's correct?

Thanks.
Have you tested something like mosfet?
I have exactly your tester,used ver 1.28 posted here a few posts before it works normal.
See the photo (https://uploads.tapatalk-cdn.com/20170421/5957eaf3f51ad5831e4279392cd3da0e.jpg)


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on April 21, 2017, 09:04:37 am
@casinada

I'have this model
http://www.ebay.it/sch/i.html?&_from=R40&_trksid=p4712.m570.l1313.TR0.TRC0.H0.TRS0&_nkw=122312989617 (http://www.ebay.it/sch/i.html?&_from=R40&_trksid=p4712.m570.l1313.TR0.TRC0.H0.TRS0&_nkw=122312989617)
i can set only back and front color .......

Another question
i set fuse 0xff 0xd9 0x04 it's correct?

Thanks.

i think i have the same type as yours, that is 'AY-AT' type, and yes, AFAIK you only able to set front&back color for that tester with the original firmware (1.12k). maybe the 'M' firmware has multiple colors display?
about the fuse, i think the correct one is : lfuse=0xF7, hfuse=0xD9, efuse=0x04.
but i could be wrong.. experts confirmation is needed for this information.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on April 21, 2017, 09:14:13 am
I am an expert.the fuses have nothing to do with color.
just write casinada version posted here 1.28 and test like I said.
anyway,look my cfg bits attached just for check
low fuse F7, high fuse D9, extended fuse FC, lock fuse FF, calibration fuse FFFFFFA8 (eXtreme burner)
did you did it like I supposed?
best regards,
pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 21, 2017, 10:18:44 am
Just in case someone is confused by efuse 0x04/0xfc. Using the default configuration file avrdude reads efuse 0xfc as 0x04. You can simply ignore that or change 0xfc to 0x04, or alternatively change avrdude's configuration file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madcat on April 21, 2017, 10:31:33 am
ooops sory.. i just had my time to edit my post earlier.. but apparently it was posted after you replied.  :palm:
no, i didn't say that the color has anything to do with the fuses.
i just try to answer your "another" question about setting the fuse, which all i know is using the one i posted earlier.
i'm sorry if it didn't help.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 21, 2017, 11:40:44 am
And regarding colors, the k-firmware has a function to change the pen and background colors. The m-firmware uses a few colors more which can be set in colors.h (before compiling the firmware).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gino_09 on April 21, 2017, 12:29:33 pm
Load 1.28 m-firmware AY-AT, color now ok but response very very slow and rotary not run i can set only pwm.

Any idea?
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on April 21, 2017, 01:30:01 pm
Load 1.28 m-firmware AY-AT, color now ok but response very very slow and rotary not run i can set only pwm.

Any idea?
Thanks
If you put inside the right quartz - I used 8 MHz - it should be fine otherwise you have to check quartz,encoder,maybe voltage issues...
First check your quartz.mine is ok
Best regards,Pierre


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 21, 2017, 01:34:47 pm
Possibly wrong clock prescaler (lfuse), something like /8 instead of /1.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jleg on April 21, 2017, 02:27:20 pm
So now I am not sure what to do (to reiterate: the original AVR is probably fried as cause of charged capacitor testing and now the tester measures wrong values). Maybe I could replace whole PCB and DIY a new one, reusing only the LCD and use PDIP atmega328.
well, i once also made the "mistake" trying to *repair* a broken LCD on my tester - only to find out later that complete new units became incredible cheap meanwhile...  ::)
http://www.ebay.com/itm/LCR-T4-Resistance-Capacitor-Diode-SCR-Transistor-ESR-Meter-Tester-9V-128-64-LCD-/191958490359?hash=item2cb19e1cf7:g:zyAAAOSw5ClXxnfh (http://www.ebay.com/itm/LCR-T4-Resistance-Capacitor-Diode-SCR-Transistor-ESR-Meter-Tester-9V-128-64-LCD-/191958490359?hash=item2cb19e1cf7:g:zyAAAOSw5ClXxnfh)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on April 21, 2017, 04:32:19 pm
Hi madires. I have  this  http://www.banggood.com/DANIU-3_5inch-Colorful-Display-Multi-functional-TFT-Backlight-Transistor-Tester-p-1083042.html (http://www.banggood.com/DANIU-3_5inch-Colorful-Display-Multi-functional-TFT-Backlight-Transistor-Tester-p-1083042.html) which has a faulty micro and I was wondering if there
is any work supporting it? It uses an atmega 324pa. I've already searched online but it looks like the info is top secret..
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 21, 2017, 04:53:31 pm
Both firmwares (k & m) support the ATmega324 (and 644/1284). If it's toast I'd recomment to replace it with a 644 which got twice the flash memory, EEPROM and RAM.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on April 21, 2017, 05:29:06 pm
Thanks madires for the quick reply. I've already got a cheap 324 installed but I'm wondering if the ir code tester and zener tester functions would be supported in the  k or m versions ?
or how difficult it would it be to add them.? I'm not good at coding and I suppose I am just looking for something already compiled to flash to micro...I know lazy  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 21, 2017, 06:03:31 pm
k: zener check
m: zener check and IR detector/decoder
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on April 21, 2017, 06:49:36 pm
Thanks madires. I'll have a play with it and see what I can come up with  :)
Title: Mega328 / LCR/T4 - changed to always on?
Post by: esrtester on April 21, 2017, 06:51:29 pm
I wonder if anybody can tell me whether the cheapo Mega328 / LCR/T4 type push button testers can be jumpered to always on?

I watched a YouTube video where somebody did a quick test of 2 different capacitors before the tester turned off - and it read both capacitors

I believe some of these testers have a row of jumpers and changing the shorting wire to another pair of jumpers changes the switch off time - anybody tried a tester without a jumper at all?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 21, 2017, 07:39:35 pm
If you run the m-firmware and power on the tester with a long key press, it will be in auto-hold mode, i.e. it will stay powered on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: esrtester on April 21, 2017, 07:49:18 pm
That's really good news - but how do you know which of the testers are running m-firmware - not seen any reference to firmware version in any of the advertisements on ebay, amazon, banggood, etc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 21, 2017, 08:17:35 pm
Simply program the MCU with the version you like ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: esrtester on April 21, 2017, 08:30:03 pm
Now it's getting complicated

I want to buy one ready made that will stay on and read ESR on caps on circuit boards

Reading loose components and identifying/testing them would be a bonus - but I could buy a second one for that if necessary

Anybody on here selling m-firmware testers?

Flashing chips is not my thing
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gino_09 on April 22, 2017, 10:01:13 am
My little contribution: Italian translation m-firmware. (If not acceptable delete as well).

--------------
Please read next two posts with correct file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 22, 2017, 02:38:23 pm
Grazie! I'll add it to the source. Some strings are a little be too long (max. 14 characters for menu items and 16 for other stuff to keep everything within the typical 16 char/line range).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gino_09 on April 22, 2017, 04:28:18 pm
Grazie! I'll add it to the source. Some strings are a little be too long (max. 14 characters for menu items and 16 for other stuff to keep everything within the typical 16 char/line range).

Correct.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 22, 2017, 10:21:09 pm
About "Accoppiatore opt". Would it be saying something different if it were optocoppia or optoisolatore instead? Also, do any of the words you used usually need an accented letter? Lastly, what encoding do you usually use for Italian when using a localized Italian operating system?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gino_09 on April 23, 2017, 11:50:41 am
Optocoppi or optoisolatore are good
https://it.m.wikipedia.org/wiki/Optoisolatore
But i think "Accoppiatore opt" is generic. There is no accented letter in traslation.
Encoding iso 8859-1 web utf-8
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 23, 2017, 09:57:33 pm
Got it. Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 24, 2017, 09:17:40 am
Correct.

Meraviglioso!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 24, 2017, 09:25:48 am
Would someone like to sponsor one or two ST7920 based LCDs?
Title: Re: $20 LCR ESR Transistor checker project
Post by: esrtester on April 24, 2017, 10:04:15 am
I like the black on white one http://www.buydisplay.com/default/catalogsearch/result/?cat=&q=ST7920 (http://www.buydisplay.com/default/catalogsearch/result/?cat=&q=ST7920)
Title: Re: $20 LCR ESR Transistor checker project
Post by: free on April 24, 2017, 02:36:10 pm
Does anyone have a backup of the original English version 2.07 of the LCR-T5 Mtester?
Thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gino_09 on April 24, 2017, 05:04:55 pm
Hi
Help..
Can anyone post zip with modified files (config and make)  for AY-AT DIY Color kit m-firmware?
I must resolve fuse problem and i think I'm wrong
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 24, 2017, 06:11:42 pm
The settings for the AY-AT DIY Color kit are listed in the "Clones" file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on April 24, 2017, 07:14:03 pm
A little bit of progress with the TC1. It appears to be using an ST7735s lcd driver ic display, see attached data sheet for the display. using
modified settings in the config_644.h see attached file I am able to get a brief display using spi bit banging..
In order to get it to make a measurement I have to press the button a second time before it times out, but it all displays very fast before "bye" and then powers off.
I'm Not sure how to keep it from timing out? the zener and ir test doesn't appear to be working either. There is an 8p soic unmarked chip U4 that appears to connected to the
power management side of things..well that's as far as I have managed to get...  :-BROKE
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on April 24, 2017, 07:26:42 pm
This is for the AY-AT with 1.28m firmware.
Note that I use an external programmer (TL866) so all the programming commands are disabled.
The fuses for the 328P as mentioned elsewhere:
LFuse: 0XF7
HFuse:0XD9
EFuse:0X04 (0XFC)
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on April 25, 2017, 09:37:54 am
Grazie! I'll add it to the source. Some strings are a little be too long (max. 14 characters for menu items and 16 for other stuff to keep everything within the typical 16 char/line range).

Correct.

Hello, I'm new at this.
Where and how is this file placed in the ESR tester?
Since I want to put it in Spanish

Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 25, 2017, 10:10:44 am
I'm Not sure how to keep it from timing out? the zener and ir test doesn't appear to be working either. There is an 8p soic unmarked chip U4 that appears to connected to the
power management side of things..well that's as far as I have managed to get...  :-BROKE

Do you got a circuit diagram for that clone?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 25, 2017, 10:14:51 am
Where and how is this file placed in the ESR tester?
Since I want to put it in Spanish

Spanish texts are included since v1.26m (UI_SPANISH) and the k-firmware also supports Spanish.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on April 25, 2017, 10:29:30 am
Where and how is this file placed in the ESR tester?
Since I want to put it in Spanish

Spanish texts are included since v1.26m (UI_SPANISH) and the k-firmware also supports Spanish.

I had the LCR-T4 which without realizing it spoiled it without realizing it when putting a capacitor without discharge.
Now I have bought another LCR-T4 and a GM328, and when I receive them upgrade to the latest version possible and be in Spanish language.

What are the latest versions for such devices?

Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 25, 2017, 10:56:29 am
The latest firmware versions are 1.13k (trunk) and v1.28m. You can get them from https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/) or https://github.com/svn2github/transistortester (https://github.com/svn2github/transistortester).
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on April 25, 2017, 12:02:58 pm
Unfortunately I've no schematic, but it is the same as this device that Dwaine posted with good photos  :-+  https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg985243/?topicseen#msg985243

U4 pins 7 and 8 go to PD1 & 2 on the micro
pin 1 & 4 is SW & Gnd
pin 5 & 6 go to P1 & P2

from the manual, see attachment.
2.7   Power off
The Multifunction Tester with automatic shutdown and manual shutdown.
?   Automatic shutdown
When the component detection completed or IR decoding completed and after reaching the automatically shut down time, the tester automatically shut down.
Automatic shutdown time can be set by the hardware jumpers, timeout support for 10s, 15s, 20s and 25s. Factory set to 20s.
 
These are the other pinouts

#define TP_ZENER         PA4       /* test pin with 10:1 voltage divider */
#define TP_REF           PA3       /* test pin with 2.5V reference and relay */
#define TP_BAT           PA5       /* test pin with 4:1 voltage divider */  This goes through a 1meg R only ?
 
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 25, 2017, 12:47:30 pm
At first glance I see a 16 MHz crystal (FREQ = 16 in Makefile). That would explain the fast display output. Please check to which MCU pin the IR receiver module's data line is connected. For the fixed IR receiver you need to enable HW_IR_RECEIVER (config.h) and set IR_PORT and so on (config_644.h). The timeout jumpers are something new. PD0 and PD1 are a serial port (reserved for serial communications), and PD2 is normally the 680 Ohms test resistor for probe #1. Seems to be a circuit with several modifications. With a little bit of reverse engineering we might be able to get that clone running.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on April 25, 2017, 01:01:47 pm
Hello madires. Here are the the files that I modified and used, there may well be errors...
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on April 25, 2017, 01:17:57 pm
config_644.h
/*
 *  IR detector/decoder
 *  - fixed module
 */

#define IR_PORT          PORTD     /* port data register */
#define IR_DDR           DDRD      /* port data direction register */
#define IR_PIN           PIND      /* port input pins register */
#define IR_DATA          PD3       /* data signal */

config.h

/*
 *  fixed IR remote control detection/decoder
 *  - requires IR receiver module, e.g. TSOP series
 *  - module is connected to fixed I/O pin
 *  - see IR_PORT for port pin (config-<MCU>.h)
 *  - uncomment to enable
 */

#define HW_IR_RECEIVER
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gino_09 on April 26, 2017, 11:56:37 am
m-firmware 1.28

Is it normal that by analyzing a component after the measurement there is no stop on the result,
but the test resumes cyclically?

Is it correct that the self-test does not require the insertion of a capacitor?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 26, 2017, 02:34:18 pm
The m-firmware supports two operations modes which are selected at power-on by the duration you press the test button. A short button press selects the continious mode (automatic cycling) and a long button press (>300ms) selects the auto-hold mode (tester waits for confirmation to continue). And yes, the self-test doesn't require a capacitor. But before running the self-adjustement you should check a film cap (220nF up to a few µF) at least three times. There's also a hardware option for a fixed adjustment cap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on April 26, 2017, 02:54:18 pm
This is for the AY-AT with 1.28m firmware.
Note that I use an external programmer (TL866) so all the programming commands are disabled.
The fuses for the 328P as mentioned elsewhere:
LFuse: 0XF7
HFuse:0XD9
EFuse:0X04 (0XFC)

Is this file for 8 or 16 Mhz?
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gino_09 on April 26, 2017, 06:46:51 pm
This is for the AY-AT with 1.28m firmware.
Note that I use an external programmer (TL866) so all the programming commands are disabled.
The fuses for the 328P as mentioned elsewhere:
LFuse: 0XF7
HFuse:0XD9
EFuse:0X04 (0XFC)

Is this file for 8 or 16 Mhz?
Thanks.

8 mhz
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on April 26, 2017, 09:57:21 pm
Do you have the 16 Mhz version maybe?
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rabbi_josiah on April 30, 2017, 04:55:25 pm
ok will try for a third time
i bought from fuzzbay a tester for $11.88
these are the two manuals they emailed me but due to size i will have to do this twice
they are in english chinese style lol
Title: Re: $20 LCR ESR Transistor checker project
Post by: rabbi_josiah on April 30, 2017, 06:50:13 pm
same board as your but different LCD screen
hope my pdf file helps anyone
Title: Re: $20 LCR ESR Transistor checker project
Post by: rabbi_josiah on April 30, 2017, 07:22:05 pm
my tester bought on eBay auction: # http://www.ebay.com/itm/111990329664?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/111990329664?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT) for $11.88 has different screen but the same board and m388 ic here is the asembly manual they sent via email to me


https://drive.google.com/file/d/0B10V3WQ_LRjGeEdYRTlKVGdkYUE/view?usp=sharing (https://drive.google.com/file/d/0B10V3WQ_LRjGeEdYRTlKVGdkYUE/view?usp=sharing)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on May 01, 2017, 07:16:02 am
Josiah,

This tester is here named as Color TFT Kit and also AY-AT.
This model is described in this forum part over and over.
However the thread is quite long already...

It starts about here:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/2050/ (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/2050/)

The screen is the same you showed, if there are differences they are minor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rabbi_josiah on May 01, 2017, 07:27:36 am
thank you very much good sir have been attempting to obtain manual then the vendor provided one was trying to share and looking through that posts seem as if the units were not the same
here is the link to show what i bought
http://www.ebay.com/itm/111990329664?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.com/itm/111990329664?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)
again just trying to be helpful with my discovery even how ever missplaced
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 01, 2017, 10:29:01 am
Nice to see LCD modules with level shifters. BTW, I'm changing all display drivers to support a common SPI framework (similar to the I2C framework). That way other SPI driven stuff can be added easily in the future. To keep the configuration simple the SPI bus can be set in the display section (just a few lines more for each display) or in a separate section. Another benefit is that the SPI bus and the control signals, like /CS, can be on different ports.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rabbi_josiah on May 01, 2017, 02:12:58 pm
well you just spoke greek not german lol
have no clue what SPI framework is at this time
i am just beginning in my electronics hobby and figured a good way for me to learn is to build
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on May 01, 2017, 04:42:22 pm
A good start is half the work...
Like Google, Wikipedia can be a good companion to search in.

https://en.m.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus (https://en.m.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on May 01, 2017, 05:55:44 pm
It starts about here:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/2050/

Willem,

When there is punctuation or other symbols, such as a dollar sign, in a URL, the forum gets confused when making it into a link. To fix it, edit the post and move the URL's end tag [/url] to the correct location (after the final slash).

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/2050/ (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/2050/)

To prevent the error when initially writing a post, select the URL with your mouse and then click the Insert Hyperlink button (looks like a globe with a document in front of it). That will explicitly set the URL start and end tags around the selection so that the forum can't mess it up.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rabbi_josiah on May 01, 2017, 07:43:19 pm
excellent post reminding me of the url language problem hyperlinking with certain html or swhtml so thanks for the intel
Title: Re: $20 LCR ESR Transistor checker project
Post by: rabbi_josiah on May 01, 2017, 07:46:15 pm
 |O
 :-//
WOW as a computer nerd should have known that none wow getting old :-BROKE i not for sissys right  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gino_09 on May 02, 2017, 08:41:44 pm
Is possible add Ir reciver function like chinese firm on m or k firmware? Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 03, 2017, 09:34:25 am
From the m-firmware's README file:

Supported protocols:
  - JVC
  - Kaseikyo (aka Japanese Code, 48 bit)
  - Matsushita/Emerson
  - Motorola
  - NEC (standard & extended)
  - RC-5 (standard)
  - RC-6 (standard)
  - Samsung (32 bit Toshiba)
  - Sharp
  - Sony SIRC (12, 15 & 20 bit)
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on May 03, 2017, 10:48:29 am
have anyone seen any of the testers with atmega644 or 1280?
or pcb's available?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 03, 2017, 12:55:48 pm
One of the clones got an ATmega 324, but I haven't seen any with a 644 or 1284. There's a PCB for the 644 circuit in Karl-Heinz's documentation (https://drive.google.com/drive/folders/0B4yqyYy2DaakZzBVU3JDSXB6S1E (https://drive.google.com/drive/folders/0B4yqyYy2DaakZzBVU3JDSXB6S1E)) and I've posted the schematic for a 644/1284 dev board a few weeks ago. If anyone is interested in the dev board I could post the KiCad files (optimized for DYI, mostly through-hole, no onboard display but easy to add).
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 04, 2017, 05:55:02 am
I've accidentally found something that I thought might be interesting. Velleman is, apparently, selling something that can identify, and I quote, "SCR, JFET, E-IGBT, D-IGBT, E-MOS, D-MOS, resistor, coil, capacitor, diode, transistor." Sound familiar? But it's an option for one of their portable DSOs, apparently. Looks like k firmware from the picture.

Here it is: https://www.vellemanprojects.eu/products/view/?id=435690 (https://www.vellemanprojects.eu/products/view/?id=435690)

Title: Re: $20 LCR ESR Transistor checker project
Post by: kripton2035 on May 04, 2017, 05:59:05 am
whaou ... and the display is quite well ... loking the same as something we already know ... no ? ;)
(https://www.vellemanprojects.eu/images/products/0/hps141_toep.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: FatuousJeffrey on May 04, 2017, 07:54:19 pm
Hey all.  First post.

Has anyone been able to build firmware that works with this color tester by Fish8840? I added the 6 pin header and am able to read and write flash with no problems.  Just can't seem to find a combination that works with this one.

I'm also looking for a backup of the original firmware. I seem to have misplaced mine  :-//

(http://2319.systems/images/tt1.jpg)
(http://2319.systems/images/tt2.jpg)
(http://2319.systems/images/tt3.jpg)
(http://2319.systems/images/tt4.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 05, 2017, 10:40:56 am
In the trunk directory (k-firmware) of the repo are the hex files for the older version with a ST7565 based display (mega328_fish8840 and mega328_fish8840_OC). I'd guess the color display is a ST7735.
Title: Re: $20 LCR ESR Transistor checker project
Post by: PointyOintment on May 05, 2017, 01:04:13 pm
Hi everybody. I'm having a problem with the kit (https://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html) I just assembled. It's reading a reasonably large capacitance (hundreds of microfarads) most of the time, with nothing connected, and also behaving erratically some of the time. The firmware version is listed in "show data" as 1.12k.

Once I got it all put together (apart from the ZIF socket, because I think I want to change its pinout first), I powered it up using a bench power supply set to 8.8 V to make sure it worked. It turned on just fine, but showed a capacitor connected. I don't remember for sure now, but I think it was shown as between 1 and 3. I restarted it many times and reran the transistor test and C+ESR@TP1:3 test through the menu many times as well. Every time, it showed a reasonably large capacitor, with a seemingly random value usually around 200–300 ?F, but sometimes as low as 90 ?F or as high as 700 ?F. Sometimes it was between 1 and 3, sometimes between 2 and 3. I don't remember seeing it between 1 and 2. About half the time, it also listed a Vloss value, ranging from 0.7% to 14% IIRC. The included 220 nF calibration capacitor didn't seem to have any effect—it's much smaller than the random variation between the readings. (With the ZIF socket not yet installed, I was putting it into the holes and holding it at an angle so it made contact.)

I ran the calibration procedure ("selftest") and it measured the 220 nF capacitor fine there (as 210 nF), but back in normal testing, it was the same as before.

I tried running it using another bench power supply, suspecting noisy power, and it worked correctly about 40% of the time. I then tried an alkaline 9 V battery that was working fine in another (non-graphical) tester, and it still read erroneously (though I only tried it once, and then considered the noise idea disproven, so put the battery back where it came from). I also tried swapping in the chip from the non-graphical tester, but it uses a different LCD interface (as well as the LCD being non-graphical), so it didn't show anything onscreen.

Around the time I put the correct chip back in, it started behaving strangely. Specifically, it would start up straight into the menu, then exit the menu back to the transistor test, go into the menu on its own, advance menu item on its own, and go back and forth between menu and frequency generator on its own (when I was trying to test the FG). I suspected a faulty switch in the encoder, but I haven't tested for that yet. It seems to have stopped that behavior now. Actually, it seemed kind of like it did that more the more it had been powered on/used recently.

The board is still a bit messy with flux residue, but I don't see how that could cause false readings of large capacitance. Wrong resistance readings, sure, but it doesn't seem to see resistance as dominant unless I short the terminals. I also looked at the circuitry between the terminals and the microcontroller, and it looks like there are only some resistors between them, certainly no large and failing capacitors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 05, 2017, 01:49:15 pm
Please re-check the probe circuit including the test resistors. Someone else had strange readings too and he found that his PCB had a bridge between two inputs (poor etching by the PCB manufacturer).
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 05, 2017, 11:41:23 pm
And someone else found the wonders of acid flux and just how badly it can mess things up when used to assemble measurement instruments. Clean that flux residue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sarahMCML on May 06, 2017, 02:59:12 am
PointyOintment
The same advice would seem to carry over to solder with 'water wash' flux. I built the same unit as you a few days ago, and although it worked fine on resistors, diodes and transistors, capacitors were way out!
What gave me a clue to my fix was the spurious 5-6Mohm resistance values that were appearing between the unused terminal and one or other of the caps terminals. The idea of strays made me check the solder type, since it was a reel I'd been given and hardly used before. Sure enough, it was the type that needed to have the water soluble flux removed!
A careful scrub with warm water and a toothbrush under the tap (on the solder side only), and a couple of hours in the oven at 80C did the trick and it now works a treat!
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on May 06, 2017, 04:12:32 pm
Good news.

In revision 728 of the "k" firmware on my LCR-T4-H, low value resistor measurement starts to work fine again.

Most of the time it shows the correct value of the resistance.

Only a few times it marks resistance + inductance + capacity + frequency at the same time as passed the revisions 722-723-725.

Every day I like these little gadgets more.

A greeting.

P.S. If Karl reads this post or someone wants to let you know it would be fine if he adds a space to line 351 of the Transistortester.h file to show the better version ("Version 1.13k").
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 11, 2017, 11:27:58 am
Hi, madires! I made the new big test of measurement of inductance. Photos can be watched here http://vrtp.ru/index.php?showtopic=26994&view=findpost&p=704718 (http://vrtp.ru/index.php?showtopic=26994&view=findpost&p=704718) . For AY-AT(20MHz crystall) of a clone I changed settings of the inductor.c file. Also the enkoder works with the "define ENCODER_PULSES 2" setup better.
The question - is a problem with measurement of big inductance (Henry), it gives in to the decision? :D :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on May 12, 2017, 04:54:26 am
I know it probably was discussed somewhere on this thread: If I'm not interested in Frequency measurement or signal generation, what is the difference between using 8, 16, or 20MHz when testing components besides being faster?
I have the crystals  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 12, 2017, 06:02:54 am
Hi, madires!
I have a question - whether it is possible to add an inductance icon on the display on the right how it is made for transistors or thyristors?  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: kripton2035 on May 12, 2017, 06:27:59 am
being somewhat lazy, I don't want to search throught the 140+ pages of this thread ...
is there some repository where I can get the different firmwares with their caracteristics ?
right now I'm searching for the zener measuring option that seems to exists ?
thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on May 12, 2017, 07:00:04 am
You need a circuit modification to test Zener diodes of more than 4 Volts as described in the manual page 12 :) or you can purchase one that has the capability:
http://www.ebay.com/itm/LCR-T6-TFT-Transistor-Tester-Zener-Diode-Triode-Detector-Capacitance-Meter-8C0E-/401011374698?hash=item5d5e23fa6a:g:NOoAAOSwhcJWH4yh (http://www.ebay.com/itm/LCR-T6-TFT-Transistor-Tester-Zener-Diode-Triode-Detector-Capacitance-Meter-8C0E-/401011374698?hash=item5d5e23fa6a:g:NOoAAOSwhcJWH4yh)
 :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 12, 2017, 10:19:15 am
The question - is a problem with measurement of big inductance (Henry), it gives in to the decision?

I've tested inductors up to 150mH, don't have any higher values.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 12, 2017, 10:23:10 am
I know it probably was discussed somewhere on this thread: If I'm not interested in Frequency measurement or signal generation, what is the difference between using 8, 16, or 20MHz when testing components besides being faster?
I have the crystals  :-//

Faster display output, especially for color displays, slighty lower range limit for inductors and other time related measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 12, 2017, 10:25:46 am
being somewhat lazy, I don't want to search throught the 140+ pages of this thread ...
is there some repository where I can get the different firmwares with their caracteristics ?
right now I'm searching for the zener measuring option that seems to exists ?
thanks.

And my lazy answer ;) https://github.com/svn2github/transistortester
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 12, 2017, 10:45:47 am
I have a question - whether it is possible to add an inductance icon on the display on the right how it is made for transistors or thyristors?  :D

Yes, it's possible. It could be done by using LCD_FancySemiPinout(), but the the symbol would waste flash memory (just a rectangular region inside a square, 50% wasted). Another approach would be to add rectangular symbols for 2-pin components (more efficient) and a display function for that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 12, 2017, 11:10:19 am
Madires, thanks for the response! It would be excellent if you added a feature for show of icons with 2 pin components in the following revision of a firmware!  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: technogeeky on May 12, 2017, 06:44:08 pm
I am getting consistently incorrect results with my GMA328 unit. All capacitor results seem to be systematically low. For instance, my known > 100 nF test capacitor was about 202 nF. The GMA328 always reports about 160 nF. Other capacitors seem to have the same systematic error. In addition, inductors seem to be systematically low. I measured a bunch of inductors of unknown value, and nearly all of them read 0.1uH or whatever the minimum value is, or just read as a resistor. Resistors seem to measure correctly.

Self-test and the more complete self-test do not seem to change this behavior.

Is there any way to investigate this further? The main difference between the schematic and my unit are that the transistors are all cheap versions of the original (e.g. they use 9014, 9012, etc). The voltage reference is a TL431. I don't have any ZIF socket or anything; I am going straight into three 22AWG silicone test leads. They are somewhat long (10 inches or so), but I calibrated that into the self-test.

The fuse configuration seems correct.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 12, 2017, 07:38:09 pm
8 or 16 MHz? Which 5V regulator?
Title: Re: $20 LCR ESR Transistor checker project
Post by: technogeeky on May 12, 2017, 07:50:44 pm
8 or 16 MHz? Which 5V regulator?


8 MHz. 1550. The fuses appear correct.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 12, 2017, 08:10:38 pm
Could be something like a clock or comparator issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on May 13, 2017, 08:41:05 am
Question:
I compiled Version 1.28m AY-AT Color and enabled the External reference. The Selftest or Show Values show Vref=1088 and not my entered Value of 2498.
Am I missing something?
*
 *  2.5V voltage reference for Vcc check
 *  - default pin: PC4 (ATmega 328)
 *  - should be at least 10 times more precise than the voltage regulator
 *  - see TP_REF for port pin (config-<MCU>.h)
 *  - uncomment to enable and also adjust UREF_25 below for your voltage
 *    reference
 */
#define HW_REF25
/*
 *  Typical voltage of 2.5V voltage reference (in mV)
 *  - see datasheet of the voltage reference
 *  - or use >= 5.5 digit DMM to measure the voltage
 */
#define UREF_25           2498

Also when I place a short between Pins 1 and 2 it measures 0 ohms  :-+ , when I place a short between Pins 2 and 3 it measures 0 ohms  :-+ but when I place a short between pins 1 and 3 it measures 20pf between pins 2 and 3.

I changed the Crystal to 20MHz   :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 13, 2017, 09:33:59 am
Is there any way to investigate this further?

Show results of the T1-T7 tests
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 13, 2017, 10:36:07 am
Question:
I compiled Version 1.28m AY-AT Color and enabled the External reference. The Selftest or Show Values show Vref=1088 and not my entered Value of 2498.
Am I missing something?

Vref is the MCU's internal bandgap reference (around 1.1V).

Also when I place a short between Pins 1 and 2 it measures 0 ohms  :-+ , when I place a short between Pins 2 and 3 it measures 0 ohms  :-+ but when I place a short between pins 1 and 3 it measures 20pf between pins 2 and 3.

The resistor check looks for a resistor in both directions. If the measurements of both directions differ too much the firmware assumes that there's something wrong. The capacitor check is run afterwards. In most cases a missed low value resistor is caused by a bad connection. Wiggle the leads a little bit and try again.

BTW, how do you power the tester?
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on May 13, 2017, 08:52:26 pm
I tried with both a 9V battery and a battery eliminator (power supply with a 9V battery connector).
I assumed that when the external reference is enabled, vref would be the external reference shown.
Is it possible to enable and disable the reference by software to be able to compare them instead of having to recompile the firmware?  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 14, 2017, 10:01:55 am
Ok! I've asked because sometimes a SMPSU might cause some issue. The external reference is used to get the offset of Vcc (5V). That's the reason why the reference should be more accurate (an order of magnitude) than the voltage regulator, and why its "fixed" voltage isn't displayed. The external reference is used when  HW_REF25 is set and the firmware detects a voltage around 2.5V. So you could also program using solder :) Adding a menu function and some control logic for a software switch should be straight forward. Be my guest ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on May 14, 2017, 01:25:51 pm
I tried with both a 9V battery and a battery eliminator (power supply with a 9V battery connector).
I assumed that when the external reference is enabled, vref would be the external reference shown.
Is it possible to enable and disable the reference by software to be able to compare them instead of having to recompile the firmware?  :)
Off course no,you have to recompile


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 14, 2017, 05:40:39 pm
Just soldered a display adapter board for an ILI9342 based display with touch screen :) Let's see if I'm able to add touch screen support to the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on May 14, 2017, 11:54:05 pm
I haven't programmed seriously for 20 years but I'm becoming dangerous again daily  :)
Is it possible that with the 20MHz crystal the tester has hard time measuring resistance lower than 0.1 ohms? It has not problem detecting the shorts for calibration.  :-//
I will go to a 16MHz crystal so I can test the K versions of the firmware as well (I prefer the m version)   :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: johwaa on May 15, 2017, 05:08:52 am
I'm working on a version of the board that drives a couple of relays connected to PC3 and PD5 (which weren't used in the version of the board that I purchased). For some reason, PC3 wants to come on regardless of what I am doing with it. Is it being driven in the assembler code?

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2017, 07:56:31 am
I haven't programmed seriously for 20 years but I'm becoming dangerous again daily  :)

Duck and cover?  >:D

Is it possible that with the 20MHz crystal the tester has hard time measuring resistance lower than 0.1 ohms? It has not problem detecting the shorts for calibration.  :-//

I haven't noticed anything like that, but I'll check a few resistors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2017, 08:04:52 am
I'm working on a version of the board that drives a couple of relays connected to PC3 and PD5 (which weren't used in the version of the board that I purchased). For some reason, PC3 wants to come on regardless of what I am doing with it. Is it being driven in the assembler code?

PC3 is the analog inut for the Zener or external voltage option for an ATmega328 based tester. If that option isn't enabled in the firmware, the pin should be in HiZ mode. Which firmware are you using?
Title: Re: $20 LCR ESR Transistor checker project
Post by: johwaa on May 16, 2017, 02:38:06 am
I'm working on a version of the board that drives a couple of relays connected to PC3 and PD5 (which weren't used in the version of the board that I purchased). For some reason, PC3 wants to come on regardless of what I am doing with it. Is it being driven in the assembler code?

PC3 is the analog inut for the Zener or external voltage option for an ATmega328 based tester. If that option isn't enabled in the firmware, the pin should be in HiZ mode. Which firmware are you using?

I'm using 1.27, and I noticed the Zener option and made sure that it was commented out. The version of the tester that I bought is this one:
http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-Meter-DIY-Kit-Square-Signal-Generator-US-46CI/141767800169?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649 (http://www.ebay.com/itm/M328-LCD-12864-Transistor-Tester-Meter-DIY-Kit-Square-Signal-Generator-US-46CI/141767800169?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649)

PD5 was also unused, so I'm using it for my "Fail" relay.

I've removed the tests for inductors, transistors, and resistors in the software. All that I am looking for is capacitance.

What this version of the tester does is to check the quality of the connection of a microphone where it connects to the wiring harness in the Headliner assembly (for a car). If the capacitor is between 100 micro-farads and 200 micro-farads I consider it a good connection. If the connection is bad, the result will be a higher capacitance, not higher resistance.

I re-created the board by hand and created a project in KiCad (with my relays) from it. From there, Hackvana made the boards for me (great resource!). I've built one board, and it works fine with the exception of the relays. It's just that the pesky relay off of PC3 keeps coming on.

I can post the code and the KiCad schematic now, the PCB layout will have to wait until I fix the footprints for most of the components (I got them wrong and the resistors and most of the capacitors don't fit correctly, once I fix it, I can post that too).

Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on May 16, 2017, 06:03:36 am

Is it possible that with the 20MHz crystal the tester has hard time measuring resistance lower than 0.1 ohms? It has not problem detecting the shorts for calibration.  :-//

I haven't noticed anything like that, but I'll check a few resistors.

The same thing happens to me in the LCR-T4-H and in the AY-AT.

In resistors less than 1 Ohm indicates missing component or marks a few picofarads.

A greeting.

P.S. In both I have installed 16 Mhz quartz crystals.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 16, 2017, 09:57:40 am
I re-created the board by hand and created a project in KiCad (with my relays) from it. From there, Hackvana made the boards for me (great resource!). I've built one board, and it works fine with the exception of the relays. It's just that the pesky relay off of PC3 keeps coming on.

How do you drive the relays?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 16, 2017, 10:07:37 am
The same thing happens to me in the LCR-T4-H and in the AY-AT.

In resistors less than 1 Ohm indicates missing component or marks a few picofarads.

A greeting.

P.S. In both I have installed 16 Mhz quartz crystals.

I've put it on my to-do list. A quick check with a 20 MHz tester and resistors < 0.1 Ohms confirms the issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 16, 2017, 10:10:26 am
For AY-AT(20MHz crystall) of a clone I changed settings of the inductor.c file. Also the enkoder works with the "define ENCODER_PULSES 2" setup better.

Could you please try "ENCODER_PULSES 4"?
Title: Re: $20 LCR ESR Transistor checker project
Post by: johwaa on May 16, 2017, 10:24:00 am
I re-created the board by hand and created a project in KiCad (with my relays) from it. From there, Hackvana made the boards for me (great resource!). I've built one board, and it works fine with the exception of the relays. It's just that the pesky relay off of PC3 keeps coming on.

How do you drive the relays?

The Atmega pins drive a transistor which in turn drives the relays.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 16, 2017, 10:51:13 am
The Atmega pins drive a transistor which in turn drives the relays.

NPN with base resistor?
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on May 16, 2017, 10:55:48 am
For AY-AT(20MHz crystall) of a clone I changed settings of the inductor.c file. Also the enkoder works with the "define ENCODER_PULSES 2" setup better.

Could you please try "ENCODER_PULSES 4"?

I tested on an AY-AT with quartz crystal of 16 Mhz with ENCODER_PULSES 4 and I noticed that it is better with ENCODER_PULSES 2.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 16, 2017, 11:41:05 am
Could you please try "ENCODER_PULSES 4"?
Hi, madires! :) I checked this mode, but I liked operation of an enkoder with digit 2 more.
 I reported about a problem with determination of resistance below 0.1 Ohms also earlier. It doesn't depend on crystal frequency. The great influence is exerted by quality of test contacts and a reliable clamp of the checked detail. But even, if to satisfy these conditions, the tester determines the low-impedance resistance not always.
Title: Re: $20 LCR ESR Transistor checker project
Post by: johwaa on May 17, 2017, 05:40:51 am
The Atmega pins drive a transistor which in turn drives the relays.

NPN with base resistor?

I think so, but I'll post the schematic tomorrow. It's on my work laptop, and I don't have it handy at the moment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 17, 2017, 09:20:36 am
I reported about a problem with determination of resistance below 0.1 Ohms also earlier. It doesn't depend on crystal frequency. The great influence is exerted by quality of test contacts and a reliable clamp of the checked detail. But even, if to satisfy these conditions, the tester determines the low-impedance resistance not always.

Of course the contact resistance might prevail, which causes some fun quite often. It's not a 4-wire measurement with gold plated kelvin probes. But I check all possibilities to be sure. Sometimes two (or even more) different problems add up. A few posts ago I've explained the forward and backward measurements for the resistor check. For values below 0.1 Ohms it allows a deviation of 500%. For example, when I put a 82mOhms resistor into a tester with a ZIF one direction measures 0.03 and the other one 0.08.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strada916 on May 17, 2017, 09:32:43 am
It would be unrealistic to try and measure sub 1 ohm on a device such as this. Just my 2c worth.

Sent from my SM-G900I using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 17, 2017, 11:33:57 am
Sometimes two (or even more) different problems add up.

Yes! The main problem with the  measurement low impedance is, that the resolution of the ADC
is unsufficient to get a 0.01 Ohm resolution.
The measurement current is only about 7mA, so 0.01 Ohm will only result to 0.07mV .
The ADC resolution with 1.1V voltage reference is about 1.07mV .
Other problem is that the tester sometimes doesn't define such low resistance at all! ???
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 17, 2017, 09:18:25 pm
Didn't realize there were so many naysayers around. Just sayin'. You're basically denying that what's already working can work, and that's after the person who made it work has told you how he's going to make it work even better.  |O Nobody's trying to defy the laws of physics here, but some amazing things can be done with a few tricks and a firm belief in success. Words of discouragement don't help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on May 17, 2017, 11:28:10 pm
We all know the limitations of the hardware. It is a nice little device :) They have done a great job with the software and greatly expanded its use. I couldn't ask for more. The only thing is to make it more reliable, of course, sometimes is due to the hardware problems like socket connection to the microcontroller, long testing wires, cheap ZIF socket, noisy power source, questionable sourced components, and it still manages to give decent results. There are lots of different hardware versions to add to the software complexity.
Probably we should define better the limits of the device so each time we go and measure something we can get similar results. :)  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: johwaa on May 18, 2017, 07:59:10 am
The Atmega pins drive a transistor which in turn drives the relays.

NPN with base resistor?

Yup, and I'm using a 2.2k resistor. BTW, I fixed the footprint, and re-laid out the board, zipped it all up and uploaded it to here. It hasn't been posted as of yet however. And I just realized that I forgot to fix my relay driver... Sigh...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 19, 2017, 06:14:53 pm
I've changed the measurement function for low value resistors (saving a few bytes and it should also help with inductors) and the tolerance logic in the resistor check function (replaced the 500% tolerance for <0.1Ohms with a better method applied to resistors <2Ohms) to cope with probe contact issues and low value resistors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on May 20, 2017, 04:01:32 am
Newbie to this thread, so some fundamental questions about the "$20 LCR ESR Transistor checker project".

What's the operating freq. of the project meter as of this writing?

Where can I find the schema and BOM?

Great project idea, BTW!
Title: Re: $20 LCR ESR Transistor checker project
Post by: jh15 on May 20, 2017, 04:18:15 am
i agree, don't want to sift through 4000 posts
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 20, 2017, 10:12:47 am
Usually the last 10 pages will give you all the links and latest news. Every two pages someone asks for firmware and documentation while excusing for not reading all 144+ pages >:D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 20, 2017, 10:23:55 am
What's the operating freq. of the project meter as of this writing?

Where can I find the schema and BOM?

Great project idea, BTW!

MCU clock is 8 or 16 MHz, optionally 20 MHz with m-firmware. Documentatiion is avaliable at https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf for example. There's also a directory with PCBs for the tester and hardware options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on May 20, 2017, 02:09:56 pm
What's the operating freq. of the project meter as of this writing?

Where can I find the schema and BOM?

Great project idea, BTW!

MCU clock is 8 or 16 MHz, optionally 20 MHz with m-firmware. Documentatiion is avaliable at https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf) for example. There's also a directory with PCBs for the tester and hardware options.

That repository (https://github.com/svn2github/transistortester (https://github.com/svn2github/transistortester)) also contains the two principle open source versions of the software. The trunk contains the version from Karl-Heinz Kübbeler based on the work of Markus Frejek. The other branch by Markus Reschke (madires in this forum) is in the "Markus" folder in the repository.

They function slightly differently and have some different options, so it is worth testing both.

You do not need to install the full Atmel development software to compile.

For Windows, you will need WinAVR to program the processor, and this includes a complete GCC compiler.
WARNING*** For some people installing WinAVR, their PATH system variable gets overwritten. It is a very good idea getting a copy of your current path before installing WinAVR. You can do this with the DOS command
PATH > path.txt

https://sourceforge.net/projects/winavr/ (https://sourceforge.net/projects/winavr/)
This post then recommends you update this to one of two particular versions of the compiler.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg825078/#msg825078 (https://www.eevblog.com/forum/testgear/)

I did originally try compiling with the latest GCC for the smaller Atmega168 processor and the code wouldn't fit in the processor's space. When I changed to the recommended versions, it just fitted.

Compiling the code yourself is worth it as you are able to turn on and off the features you want, and possible tweak some constants. For both versions, you usually only have to edit the config.h file. Markus's config.h file is very well self-documented, so it might be the easier version to try first.

I hope that is an accurate summary.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Sredni on May 22, 2017, 02:52:31 pm
Last week I assembled my first transistor tester (bought the kit on Amazon). It appears to be working  but there are a few strange things going on. Maybe you can help me in troubleshooting it? It's the kit in a red PCB board with

  k1036038s
  2578AY-AT

It's the same layout as shown in the attached picture (taken from the net, probably this very forum).
It came with firmware version 1.12k and a spare 7550 (for which I was unable to find a datasheet) and I have already done the calibration procedure twice - from the menu.

Here are the oddities, in no particular order:

0 - After hours of non use, battery voltage is reported lower than what it actually is: at startup it says "Battery 8.9V while the actual battery with no load is 9.2 V (IIRC). This could be just a loading effect, but it is worth mentioning it. See also point 4

1 - When I repeat the measure of a resistance I get increasingly lower values. A 12.5k resistor is given as 12100 ohm the first time, 11980 ohm the second time, 11648, 11245, 10956, 10437, ... (I am making up the values right now, but that's the trend - with the resistor untouched and only subsequent pressing of the knob I went down under 9k with no fixed point in sight). And this is bad.

2 - The same is going on for caps, but I could attribute that to the fact the the measuring procedure is charging them a bit 9316 pF, 9281pF, 8953pF, 8619pF, 8307pF,... and these are actual values just measured with the time between them due to typing the numbers in this post.(http://)

3 - The spare 7550 is not identified. Is this normal for this firmware version?

4 - I just noticed that battery value too is getting lower at each pushing of the knob, only to come back to 8.9V if I leave it off for a long time.

What do you think?
there mus be a cap somewhere that is not discharging?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strada916 on May 22, 2017, 03:39:40 pm
Last week I assembled my first transistor tester (bought the kit on Amazon). It appears to be working  but there are a few strange things going on. Maybe you can help me in troubleshooting it? It's the kit in a red PCB board with

  k1036038s
  2578AY-AT

It's the same layout as shown in the attached picture (taken from the net, probably this very forum).
It came with firmware version 1.12k and a spare 7550 (for which I was unable to find a datasheet) and I have already done the calibration procedure twice - from the menu.

Here are the oddities, in no particular order:

0 - After hours of non use, battery voltage is reported lower than what it actually is: at startup it says "Battery 8.9V while the actual battery with no load is 9.2 V (IIRC). This could be just a loading effect, but it is worth mentioning it. See also point 4

1 - When I repeat the measure of a resistance I get increasingly lower values. A 12.5k resistor is given as 12100 ohm the first time, 11980 ohm the second time, 11648, 11245, 10956, 10437, ... (I am making up the values right now, but that's the trend - with the resistor untouched and only subsequent pressing of the knob I went down under 9k with no fixed point in sight). And this is bad.

2 - The same is going on for caps, but I could attribute that to the fact the the measuring procedure is charging them a bit 9316 pF, 9281pF, 8953pF, 8619pF, 8307pF,... and these are actual values just measured with the time between them due to typing the numbers in this post.(http://)

3 - The spare 7550 is not identified. Is this normal for this firmware version?

4 - I just noticed that battery value too is getting lower at each pushing of the knob, only to come back to 8.9V if I leave it off for a long time.

What do you think?
there mus be a cap somewhere that is not discharging?
I'll be looking at the documentation for these testers(look at repository manual) and reading the section. "Chinese clones"
Check the power up circuit. eIt can be draining the battery?
I'd also check the battery voltage with a known meter whilst the unit is powered up.

Edited. Reread comment. Disregard y first sentence.


Sent from my SM-G900I using Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on May 22, 2017, 03:48:14 pm
It came with firmware version 1.12k and a spare 7550 (for which I was unable to find a datasheet).

www.e-ele.net/DataSheet/HT75XX-1.pdf (http://www.e-ele.net/DataSheet/HT75XX-1.pdf)

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 22, 2017, 04:15:42 pm
4 - I just noticed that battery value too is getting lower at each pushing of the knob, only to come back to 8.9V if I leave it off for a long time.

What do you think?
there mus be a cap somewhere that is not discharging?

Please power the tester with a lab PSU and check again. Also observe the current draw.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on May 23, 2017, 12:14:47 am
Last week I assembled my first transistor tester (bought the kit on Amazon). It appears to be working  but there are a few strange things going on. Maybe you can help me in troubleshooting it? It's the kit in a red PCB board with

  k1036038s
  2578AY-AT

I have attached the documentation for the board. I think the circuit is pretty right, except I don't think your board has diode D1 from the battery.
Quote

0 - After hours of non use, battery voltage is reported lower than what it actually is: at startup it says "Battery 8.9V while the actual battery with no load is 9.2 V (IIRC). This could be just a loading effect, but it is worth mentioning it. See also point 4
The battery voltage is measured after going through transistor T1. There could be a small voltage drop across it. Also if you compile your own code, you can calibrate the battery voltage. I did some notes on this a few posts back. Since you have a socket, it is a really good idea to have a spare processor IC (or a few). It is probably a good idea anyway getting some 16MHz crystals of ebay, and modifying the code for 16MHz.

You will need something to program the chip in. If you have an arduino board, you can hook up an arduino as a programmer for the atmega processor.

But Version 1.12k, that should be fine - you shouldn't have to do anything.
Quote
...

4 - I just noticed that battery value too is getting lower at each pushing of the knob, only to come back to 8.9V if I leave it off for a long time.
Just check the circuit around T1 is working correctly, When the tester is off, there should be no volts at all across the 33K base resistor R14. This is the one on the left edge of the board next to the 10uF cap and the 9012 transistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 23, 2017, 06:19:15 pm
[...]

What do you think?
there mus be a cap somewhere that is not discharging?

I think your regulator may not be regulating. Observe your VCC over time during operation. Also, extreme negative temperatures of the climate in your region may have something to do with this.  :P
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on May 25, 2017, 09:24:40 pm
What determines whether the tester is using the Vcc (5V) as reference or the external 2.5V reference and how do you force either one to be the reference?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 26, 2017, 05:59:01 am
Why would you want to force that? It uses the 2.5V reference (if it is present) to see how far the VCC is from the ideal 5.0V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on May 26, 2017, 06:39:38 am
@hapless, you didn't answer my question.  Just because the 2.5v reference is present it should NOT be the default reference.  If the 2.5V reference is a crappy TL431 and the Vcc regulator is much more accurate then I may want to use the Vcc as a reference and not the 2.5V.  On the other hand, if I have a very precise 2.5v 0.1% reference (not a TL431) and the Vcc regulator is a crappy 7805 5% then I may want to use the 2.5V as a reference. 

Again, the question is what determines whether the tester is using the Vcc (5V) as reference or the external 2.5V reference and how do I select which one I want to use?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 26, 2017, 01:20:28 pm
k-firmware: If a voltage around 2.5V is detected at the pin for the external reference, it's used. You can disable the external reference by removing it or modifying the source.
m-firmware: If HW_REF25 is defined and a voltage around 2.5V is detected at the pin for the external reference, it's used. You can disable the external reference by removing it or undefining HW_REF25.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 26, 2017, 02:57:23 pm
@hapless, you didn't answer my question.  Just because the 2.5v reference is present it should NOT be the default reference.  If the 2.5V reference is a crappy TL431 and the Vcc regulator is much more accurate then I may want to use the Vcc as a reference and not the 2.5V.  On the other hand, if I have a very precise 2.5v 0.1% reference (not a TL431) and the Vcc regulator is a crappy 7805 5% then I may want to use the 2.5V as a reference. 

Again, the question is what determines whether the tester is using the Vcc (5V) as reference or the external 2.5V reference and how do I select which one I want to use?

You "select" it by having or not having it connected, that is what determines its use, unless you want to mess around with the firmware like madires describes above.

Your premise makes no sense though. If the 2.5V reference is not an order of magnitude more accurate than your regulator, then what is it doing there anyway? You don't want your circuit to have parts that do nothing. Remove it. Then the firmware will use the 5V without comparing it to a known reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on May 27, 2017, 02:04:05 am
k-firmware: If a voltage around 2.5V is detected at the pin for the external reference, it's used. You can disable the external reference by removing it or modifying the source.
m-firmware: If HW_REF25 is defined and a voltage around 2.5V is detected at the pin for the external reference, it's used. You can disable the external reference by removing it or undefining HW_REF25.
Thanks for the info, so let say I have the 5v Vcc regulator and 2.5v reference both are 1% accurate.  Which way would I get more accurate measurement, removing the 2.5v reference so the tester will be using the Vcc as reference or leaving the 2.5v reference so the tester will be using the 2.5v as reference? 

I don't believe or it doesn't make any sense that 2.5v reference really have to be an order of magnitude more accurate than the Vcc regulator to get more accurate measurements?  Most of the Chinese clones use a standard TL431 which has 2% accuracy and a Vcc regulator 7550 which has 3% accuracy.  So if the 2.5v reference have to be an order of magnitude more accurate to get better performance then it doesn't make sense why they would have the TL431.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 27, 2017, 03:25:17 am
I don't believe or it doesn't make any sense that 2.5v reference really have to be an order of magnitude more accurate than the Vcc regulator to get more accurate measurements?  Most of the Chinese clones use a standard TL431 which has 2% accuracy and a Vcc regulator 7550 which has 3% accuracy.  So if the 2.5v reference have to be an order of magnitude more accurate to get better performance then it doesn't make sense why they would have the TL431.

Cost. TL431 and 7550 can probably be had for the least amount of money, so that's what they use. Do you believe that all the Chinese "manufacturers" read or understand every detail in the manual? They just look at the schematic. Some of their early versions had a regular zener diode in place of a voltage reference to prove that. Just because they are doing it doesn't mean that it's the best or even the correct thing to do.

As for what I said about order of magnitude, here's a quote directly from the README file included in the m firmware:
Quote
The external 2.5V voltage reference should be only enabled if it's at least 10 times more precise than the voltage regulator. Otherwise it would make the results worse.
There may even be some truth to that...

I'll leave the other part of your question to someone who's had some practical experience experimenting with this (though the above quote probably answers it anyhow).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 27, 2017, 11:28:09 am
Thanks for the info, so let say I have the 5v Vcc regulator and 2.5v reference both are 1% accurate.  Which way would I get more accurate measurement, removing the 2.5v reference so the tester will be using the Vcc as reference or leaving the 2.5v reference so the tester will be using the 2.5v as reference? 

By removing the external 2.5V reference.

I don't believe or it doesn't make any sense that 2.5v reference really have to be an order of magnitude more accurate than the Vcc regulator to get more accurate measurements?  Most of the Chinese clones use a standard TL431 which has 2% accuracy and a Vcc regulator 7550 which has 3% accuracy.  So if the 2.5v reference have to be an order of magnitude more accurate to get better performance then it doesn't make sense why they would have the TL431.

That topic is called error calculation ;) Based on the current hardware and software design the maximum total error is larger when the 5V regulator and the 2.5V reference got about the same accuracy. If the 2.5V reference is around 5 times more accurate the total error is the same as having just the 5V regulator. And at about 8 times the external reference starts to provide a real benefit.

Regarding the Chinese clones, I think hapless hit the nail. IIRC, Karl-Heinz has a section in his documentation explaining how to remove the zener used as reference by some early clone to improve performance ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on May 27, 2017, 04:00:33 pm
Do you believe that all the Chinese "manufacturers" read or understand every detail in the manual? They just look at the schematic.

that's not true, you obviously dont monitor the german forum.
hint: they are active on it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 27, 2017, 05:47:47 pm
If there was a particular post or series of posts over there that make my words not true, please post a link to it. I'd love to read how all the Chinese purveyors of these clones suddenly understand every detail in the manual and are now supplying all the right parts with the necessary tolerances.

Yes, ever since the thread became too large for online translators to handle I rarely visit there. Still, I see no relevance. Being active on a forum and understanding the manual are two different things. For me, the proof is in the pudding, as they keep pairing low-precision references with regulators that are only slightly worse, so they are doing the wrong thing regardless. This means that either they still don't understand the manual, or they understand it well but include the TL431 out of spite and because they don't want the opportunity to save on voltage references...
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on May 27, 2017, 05:50:58 pm
That topic is called error calculation ;) Based on the current hardware and software design the maximum total error is larger when the 5V regulator and the 2.5V reference got about the same accuracy. If the 2.5V reference is around 5 times more accurate the total error is the same as having just the 5V regulator. And at about 8 times the external reference starts to provide a real benefit.

If that is the case, then to obtain a more accurate performance of these testers every Chinese tester owner should remove the 2.5v reference as I am not aware of any of them using a more accurate 2.5v reference than an LM341 which has only a 3% accuracy.  If your Vcc regulator is 7550 which has a 3% accuracy then you would need a 2.5v reference better than 0.5% which would be an LM4040 type or better.

It would be interesting to see if the Chinese manufacturers are reading this forum and the next batch of these tester they will eliminate the 2.5v reference completely, obtain better performance and save a few of cents from their cost. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 27, 2017, 06:01:03 pm
More or less. In some cases, the actual voltage of even a 3% reference can be almost dead on, while the regulator may be at the edge of its spec, in which case leaving the reference in would do good.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on May 27, 2017, 06:30:50 pm
Unless you have a DVM which is more accurate than ±0.25% (not many people have such DVM) you will never know, beside initial accuracy is just one accuracy parameter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 27, 2017, 06:41:27 pm
Yes, and don't forget that these things drift, too.  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on May 27, 2017, 08:25:07 pm
If there was a particular post or series of posts over there that make my words not true, please post a link to it.

main guy
https://www.mikrocontroller.net/user/show/zhq_s (https://www.mikrocontroller.net/user/show/zhq_s)

nice pcb!
https://www.mikrocontroller.net/topic/248078?page=8#4280171 (https://www.mikrocontroller.net/topic/248078?page=8#4280171)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 28, 2017, 03:04:37 am
I like that person's progress. Unfortunately, I found nothing to indicate that I'm wrong (or right). It would be interesting to see a close-up of the insides of one of his (her?) clones. If things proved to be really turning for the better, I'd be happy.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 28, 2017, 10:52:48 am
If that is the case, then to obtain a more accurate performance of these testers every Chinese tester owner should remove the 2.5v reference as I am not aware of any of them using a more accurate 2.5v reference than an LM341 which has only a 3% accuracy.  If your Vcc regulator is 7550 which has a 3% accuracy then you would need a 2.5v reference better than 0.5% which would be an LM4040 type or better.

Yup, that's what I've written several times in this thread. If you use a crude regulator add a LM4040. Or use something like the MCP1702-5002. You can also measure the regulator and/or external reference with a proper DMM, and update the voltages in the source code.

PS: There are 0.5% TL431s
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on May 30, 2017, 04:46:52 pm
Thanks for the discussion guys, it intrigued me enough to replace my TL431 with a LM4040.
After it was said and done the tester shows VCC=5.03 just as before so guess my two samples where the same ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mechatrommer on May 31, 2017, 05:50:33 pm
hi thanks for all the effort esp to Markus F (madires) and Karl-Heinz Kübbeler...

1 question... i downloaded fw transistortester-mega328_st7565_kit.tar.gz and replaced the corrupted font china original fw. its better in most aspects (i still can confirmed one occasion of monitor hanging when i click the encoder, the fix is unplug the power), just i need to tweak some GUI a little bit. i downloaded the source code transistortester-Markus.tar.gz in there there a lot of versions 0.99 - 1.28m, classic trendy etc.. the question is... which source code version that corresponds to transistortester-mega328_st7565_kit.tar.gz fw (ver 1.13k)? thanks.

for my (good) reference later:
url=https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1213570/#msg1213570 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1213570/#msg1213570)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg825078/#msg825078 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg825078/#msg825078)
https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 31, 2017, 06:38:23 pm
Thanks, but I'm Markus R. ;) Markus F. who designed the original version abandoned the project several years ago. Karl-Heinz took over and I've joined in a little bit later. Simply use the latest version of the m-firmware, which is 1.28m at the moment. I think the kit you've got is the M12864 DIY Transistor Tester and the required settings are described in the Clones file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 06, 2017, 07:54:31 pm
The next m-firmware version will support the ST7920 which is a PITA. Does that controller have an issue when setting the GDRAM address twice without sending any data after the first time? I got a report about a "black screen" PCD8544 when running the ATmega at 16 MHz. Anyone else with that problem? Strangely the PCD8544's datasheet doesn't give any hints about command execution times, or have I missed that?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 07, 2017, 12:35:22 pm
Unfortunately, I have no experience with ST7920, but maybe this is relevant:

Quote from: st7920_chinese.pdf
After address set to read (CGRAM,DDRAM,IRAM.....)a DUMMY READ is required.

As for PCD8544, I have a "Nokia" display (not sure what controller it actually uses), and this thing took a little while to get going at first. It gave black screen, garbled screen, no output, you name it. Eventually it seemed to work fine. These so-called modules have the LCD connected to the PCB with a zebra strip, and this doesn't always make good contact. That's what happened to me. That was on an 8MHz unit. I will later try to wire up my 16MHz one to this display to see if I can reproduce the problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 07, 2017, 04:54:30 pm
Thanks! I've checked the PCD8544 with a tester running at 20 MHz and no problem at all.
Title: Re: $20 LCR ESR Transistor checker project
Post by: garymck on June 08, 2017, 05:07:18 am
Hi,
I have built one of these transistor tester kits, however it has very early firmware which I would like to update. After reading many pages of this thread I found the following that relates  to my tester"

quote from: mauroh on April 02, 2017, 03:10:26 AM
To ElectronicCat:
If I got it correctly you have this:

http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html?rmmds=search (http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html?rmmds=search)

The sources and already compiled firmware are here
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)

Ciao
    Mauro
Quote from: madires on April 02, 2017, 03:00:06 AM

his refers to exactly the kit I have. I have one VERY BASIC question (I'm a beginner).... If I go to the firmware link above I don't get donloadable files...I get a web page that includes stuff like:


1   :10000000310803083320342D33306E46284C290044
2   :100010005245465F523D005245465F433D00203EFB
3   :100020003130306E460066706E056D006B4D00110C
4   :100030001111131D101000000E11110A1B00041FD6
5   :10004000111111111F04001E0203021E0000000FF7
6   :100050000818080F00001113171F171311001119AA
7   :100060001D1F1D1911001B1B1B1B1B1B1B005244BA
8   :10007000533D005B435D0031080308332000310825
9   :10008000070608090A08332000432B455352405401

Do I just copy this page and save it using a text editor? If not how do I download the eep and hex files?

I'm sure everybody here knows how to do this, but I've never done this stuff before, and after spending 4 hours reading this thread I've decided to risk asking this!
TIA
Gary
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 08, 2017, 06:35:30 am
garymck,you watch a screenshot.The archive which you load needs to be unpacked and receive the necessary files. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ebclr on June 08, 2017, 06:47:07 am
This may help you understand that you get the correct thing

https://en.wikipedia.org/wiki/Intel_HEX
Title: Re: $20 LCR ESR Transistor checker project
Post by: garymck on June 08, 2017, 07:33:09 am
Thanks guys,
got it....

tried programming the chip with:

avrdude -F -c usbasp -p m328p -B 4.0 -e -u flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

However get an error at the end (pic)

Transistor Tester will now not work. How can I salvage it? - Is the Avrdude command correct?
cheers
Gary
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 08, 2017, 10:21:13 am
that's o.k.
it's a known issue with some of the chips.
you sent an 8bit number, but that location only uses about 5bits, so the remaining ones have a varying value depending on the batch.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 08, 2017, 10:21:49 am
You can ignore the "0xfc != 0x04" error. It's caused by the standard configuration of avrdude.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 08, 2017, 10:25:20 am
this is the string i use:
Quote
avrdude -c USBasp -P usb -p m328p -U flash:w:TransistorTester.hex \-U eeprom:w:TransistorTester.eep \-U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m


THIS WONT WORK ON WINDOW$10
Title: Re: $20 LCR ESR Transistor checker project
Post by: garymck on June 08, 2017, 11:39:28 am
Thanks,
this got me close, the device now boots, but the graphic screen is unreadable.

Must be a fuse option? I'm using the DIY M12864 Graphics Version...
cheers
Gary

AVRDude reports not error messages

this is the string i use:
Quote
avrdude -c USBasp -P usb -p m328p -U flash:w:TransistorTester.hex \-U eeprom:w:TransistorTester.eep \-U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:w:0xfc:m


THIS WONT WORK ON WINDOW$10
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 08, 2017, 11:42:23 am
your problems are not the fuse bytes.

if you use windows10, it will cut that line short and only program some of the stuff.
if your on 10, you need to use seperate lines for the flash,eeprom and fuses.
or put it in a batchfile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 08, 2017, 01:01:39 pm
I got a report about a "black screen" PCD8544 when running the ATmega at 16 MHz. Anyone else with that problem? Strangely the PCD8544's datasheet doesn't give any hints about command execution times, or have I missed that?

IIUC, the controller is expected to complete most commands in 100ns and the clock ticks every 250ns. Other than that... I don't know where to find any relevant information on this. Individual modules may have timing-specific problems, I guess, but I'd still suspect something wrong physically (intermittent connection, incorrect wiring, etc). Tried a Nokia display it on my 16 MHz unit and it works well. *shrug*

NB: I'm using the m firmware for this. Haven't tested with k.
Title: Re: $20 LCR ESR Transistor checker project
Post by: garymck on June 08, 2017, 01:05:56 pm
Hi
I'm using Widows 7 64 bit...
cheers
Gary

your problems are not the fuse bytes.

if you use windows10, it will cut that line short and only program some of the stuff.
if your on 10, you need to use seperate lines for the flash,eeprom and fuses.
or put it in a batchfile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: garymck on June 08, 2017, 01:13:38 pm
Tried it anyway and splitting the commands seems to work!

cheers
Gary

Hi
I'm using Widows 7 64 bit...
cheers
Gary

your problems are not the fuse bytes.

if you use windows10, it will cut that line short and only program some of the stuff.
if your on 10, you need to use seperate lines for the flash,eeprom and fuses.
or put it in a batchfile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 08, 2017, 01:19:51 pm
well that's not good,
it means one of the "updates" has made it worse!!
7 never originally had that issue, only 10!!  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vtile on June 13, 2017, 11:04:12 am
I have a guestion regarding the tester. Are these available (in somewhat quality build) somewhere or as a kit. If these are sold as a kits or as a ready PCB units what is the magic string of words to find one.

I noticed that there is similar units in many auction sites on the net. Is there any specific things to identify the bad aples from the good ones?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ebclr on June 13, 2017, 11:49:53 am
Magic words = avr+transistor+tester


https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20170613034920&SearchText=avr+transistor+tester (https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20170613034920&SearchText=avr+transistor+tester)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on June 13, 2017, 11:51:21 am
Search for "GM328 ESR" or "GM328 Transistor Tester"

Look e.g. on AliExpress like:
https://www.aliexpress.com/w/wholesale-GM328-ESR.html?spm=2114.01010208.0.0.RLTD73&site=glo&SearchText=GM328+ESR&g=y&SortType=price_asc&groupsort=1&tc=af&initiative_id=SB_20170613034612 (https://www.aliexpress.com/w/wholesale-GM328-ESR.html?spm=2114.01010208.0.0.RLTD73&site=glo&SearchText=GM328+ESR&g=y&SortType=price_asc&groupsort=1&tc=af&initiative_id=SB_20170613034612)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vtile on June 13, 2017, 12:32:03 pm
Thanks. Ordering one of those xxxx328 based units, hopefully I don't end up with poor ripoff of the original excellent project. Too much work to hunt down all invidual components and ordering PCB somewhere, easier to get premade unit and maybe then modify it with better components if needed.   ??? :)

I were actually hoping that there would have been somesort of "official" kit somewhere to support the project.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 13, 2017, 01:36:40 pm
So far no support of any kind from the Chinese manufacturers. It would be nice if they would send us samples of their copy of the Transistor Tester to enable us to keep the firmware compatible and provide working settings. A lot of the buyers don't even know that it's an OHSW project and that they can update the firmware. Sellers on ebay and what have you - also the manufacturers - usually don't add any hint about the project. A German maker magazine had a report about the Transistor Tester a few years ago and totally missed the OSHW project too (how embarrassing for them >:D ). They all are missing the good stuff!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 15, 2017, 02:23:08 pm
Another update about the m-firmware. After moving the SPI functionality from the display drivers into a central SPI driver I've started with writing a driver for the ADS7843/XPT2046 touch screen controller. The central SPI driver is necessary for running several chips on the same bus, which includes things like changing the bus clock for different chips. The next step is to add touch screen support to the UI. My idea is to use the last character line for navigation and control, for example three buttons for back, forward and enter/go. For menus maybe also invisible up/down bars. What do you think?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 15, 2017, 04:00:47 pm
Madires,your project will be similar to this? https://www.youtube.com/watch?v=-Xpppa6U78Y (https://www.youtube.com/watch?v=-Xpppa6U78Y) :D :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 15, 2017, 04:34:10 pm
The UI will stay the same, just with the option of a touch screen. The only visible difference would be up to three touch buttons in the bottom line. It has to be that simple to support small screens. I think three buttons at the bottom of a 2.4" screen is feasable.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 15, 2017, 04:55:00 pm
madires, i understood you correctly!  :) From the project which i stated above it is possible to use some ideas on the user interface?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 15, 2017, 05:59:12 pm
... when we got a tester with an ARM based MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 15, 2017, 06:15:24 pm
it's my understanding that the entire concept is based around very extensive knowlege of how the DAC's and ADC's behave.

if you tried to port it from AVR to a different platform you would be back to square one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 15, 2017, 07:29:51 pm
Yes, the most important points are the 5V operating voltage, the knowledge of the MCU specifics und the simple design. Moving to an ARM based MCU or something similar would require a lot of additional circuitry for 5V switching and ADC-ing. But it could provide the possibility of using additional voltages and higher currents. For the foreseeable future we'll stay with the 328 and 664/1284.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 16, 2017, 01:18:23 am
I think indman was referring to the UI when he said that maybe some ideas could be taken from it. Perhaps worth considering, though personally, I see nothing wrong with just three simple hotspot buttons for the functions that are currently handled by a rotary encoder or hardware buttons. KISS (https://en.wikipedia.org/wiki/KISS_principle)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 16, 2017, 02:27:34 am
The next step is to add touch screen support to the UI. My idea is to use the last character line for navigation and control, for example three buttons for back, forward and enter/go.

Does that assume that, on such a tester, touch is the exclusive interface (no other controls, other than on/off switch)?

Quote
For menus maybe also invisible up/down bars. What do you think?

I'm not sure I follow what the invisible up/down bars refer to and why they're invisible. The back/forward on-screen buttons seem as though they'll work fine on the menus, although up/down buttons might be better for spatial congruence.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 16, 2017, 10:21:17 am
It should be an option, i.e. you can choose between On/test push button only, rotary encoder, On/Test plus up/down push buttons or On/Test plus touch screen. Or you could use multiple in parallel. What I've meant with "invisible up/down bars" is using the top two character lines as up and the bottom two lines as down button, which would be handy for menus. Or the left three and right three columns to decrease/increase a frequency for example. Could be even better than visible buttons at the bottom. My goal is to create a simple and intuitive touch interface. So I'm trying to do some brainstorming with you all.
Title: Re: $20 LCR ESR Transistor checker project
Post by: maggotronix on June 16, 2017, 10:44:08 am
Is there an already-constructed tester available out there on aliexpress or banggood or something? Just plug and go? Or maybe I should just lump it & buy the Atlas DCA? Are there quantitative differences? I'm not interested in a "kit", I want it pre-made to use to construct my own projects.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 16, 2017, 12:08:03 pm
in that case, get the TC1 in a case with built in lithium battery that also tests zener diodes.

http://www.ebay.co.uk/itm/272671833854 (http://www.ebay.co.uk/itm/272671833854)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on June 16, 2017, 03:10:47 pm
Hi.

I'm having some problems with the latest firmware revisions k (722 and 723) in measuring medium-low resistors value with my LCR-T4-H testers.

However with 729 and previous revisions work perfectly.

I attached some photos of the problem in question.

Is someone else going on?

Thank you and greetings.

Hi, after much research I think I have found the problem of measurement error in low value resistors in my LCR-T4-H.

It all started when I installed a voltage regulator MCP1702T-5002E more precise than the 78L05 and replaced the two diodes 1N4148 with an AMS1117-3.3v.

At first and with the old firmwares worked well, but with the most modern fimwares began to fail.

The problem seems to lie in the filtering of the main voltage of 5v for these LDO, in a Russian forum I saw a similar problem of measuring quartz crystals with nothing fitted in the zocalo ZIF, and applying the proposed solution to my tester has been Corrected said measurement of resistances of low value.

The solution consists in adding 3 capacitors of 100nF to the power and the reset of the Atmega328.

Attached two photos, one of the Russian solution and another of the capacitors I have put in my tester.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on June 16, 2017, 06:57:00 pm
Hi.
Do not discharge a capacitor and break the IC.
Change it and use it to modify it as you can see in the images.
Program it and just turn on the led but nothing appears on the screen.

If I put a led in the test socket flashes and seems to be recognizing it, I put a link where it can be seen.
https://mega.nz/# (https://mega.nz/#)!F8ACmKJZ!TLnpOIBjWBGafHaxHDqsrOvFWGPSvqfUsWK4r1fBG8o

Any solution?

Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 17, 2017, 02:23:27 am
Assuming that the same firmware worked with the old MCU, maybe there is a problem with the soldering: The MCU leads that connect to the display could be either shorted or disconnected. There's also a chance that your new MCU has an issue with that particular port, in which case you may need to try another ATMega.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 17, 2017, 03:19:27 am
It should be an option, i.e. you can choose between On/test push button only, rotary encoder, On/Test plus up/down push buttons or On/Test plus touch screen. Or you could use multiple in parallel.

Ah, yes. I thought you had a particular implementation in mind. Of course, it's intended to be configurable.

Quote
What I've meant with "invisible up/down bars" is using the top two character lines as up and the bottom two lines as down button, which would be handy for menus. Or the left three and right three rows to decrease/increase a frequency for example. Could be even better than visible buttons at the bottom.

I got it now. Yes, that would certainly save visual space. I suppose it might catch people off-guard if they don't read about it before loading. ;D

Quote
My goal is to create a simple and intuitive touch interface. So I'm trying to do some brainstorming with you all.

Yep, I like the concept. Perhaps start with a test version that works as you've described. Then, folks who have a touchscreen could give feedback after interacting with it for a bit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 17, 2017, 07:55:04 pm
Quote
What I've meant with "invisible up/down bars" is using the top two character lines as up and the bottom two lines as down button, which would be handy for menus. Or the left three and right three rows to decrease/increase a frequency for example. Could be even better than visible buttons at the bottom.

I got it now. Yes, that would certainly save visual space. I suppose it might catch people off-guard if they don't read about it before loading. ;D

To help with that, a disappearing hint (in the form of inverted arrows) could be shown where the hotspots are. Of course, the ability to drag a menu up and down and tap the selected option would probably be more intuitive for me personally, and probably wouldn't require such hints.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on June 21, 2017, 09:30:19 am
Hi all,
I've got a EZM 328 build that runs the (SVN684) - v2 firmware.(I don't know any more about the firmware I've just copied the name of a folder I've probably placed the .hex I used to update my firmware the last time.
I think that was roughly 9-10 months ago..
My device is the same as this one : http://www.ebay.com/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/201663141755?hash=item2ef40f577b:g:plMAAOSwFe5Xzxsd (http://www.ebay.com/itm/2016-EZM328-GM328R-transistor-tester-ESR-frequency-meter-square-wave-genera-/201663141755?hash=item2ef40f577b:g:plMAAOSwFe5Xzxsd)

So ,what would be the latest firmware version for this device?Am I already running it?

I have a tl866 too so I can use that instead of in-circuit programming I've used the last time.

Can I just write the latest .hex to the atmel mcu or I need to set fuses etc?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 21, 2017, 09:59:19 am
i built that firmware, it's specific for the *real* GM328 hardware.
i say real, because some sellers are putting that name on other unrelated stuff now!!
for anybody about to buy from ebay, the GM328 does NOT have a colour display for a start!
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on June 21, 2017, 03:15:17 pm
So is this the latest version or there is a newer one for this one?
Mine does not have the ezm electronics logo but it's identical to the one I posted.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on June 21, 2017, 03:17:26 pm
it's well out of date, i built that in january i think.
i'v not made a newer one though because of change of address resulting in my main computer ending up in a box.  :--
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on June 24, 2017, 08:24:13 am
I discovered that changing the HT7550 by an MCP1702T-5002E/TO in an AY-AT Diy Kit produces the same measurement failure in low-value resistors as occurred in LCR-T4-H although less frequent.

The solution has been the same, place three capacitors of 100nF, two in the 5v power lines of the processor and another in the reset.

Attached photos of the process.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 25, 2017, 02:43:02 am
Have you tried with a single capacitor on AVCC only? I can understand the ones on VCC and AVCC, but are you sure that the one on the reset pin actually helps with this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on June 25, 2017, 06:03:17 am
I certainly have not tried to filter only the main voltage (VCC and AVCC), but as I said before in post #3649, in the Russian forum they advise to put all three, and since it cost me no work, I also installed the reset .

I am almost sure that the capacitor of the reset is not necessary, but if it improves in some stability I prefer to leave it on.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 25, 2017, 10:57:26 am
The inductance measurement uses high current (exceeding the maximum of an IO pin) for a very short period when measuring a low inductance. Therefore the LDO's output cap should be large enough. I use 2.2µF with the MCP1702-5005 usually. An additional bypass cap at the MCU is also fine. The circuit diagram for one of the kits shows only a 100nF cap right of the 7550, which isn't sufficient.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on June 25, 2017, 07:27:58 pm
Hi, I have two of these testers, AY-AT and T3-T4 with the same firmware, ver. 736 running @16MHz.  When measuring small inductors <100uH in this case ~30uH, the T3-T4 version looks like it display the correct inductance.  On the AY-AT version with the same 30uH inductor, it displays "50nH if 21nF" (yes "50nH if 21nF" not a typo) what does it mean?  Also, both testers displays some sort of frequency in kHz what does the frequency mean?  Any way to have the AY-AT version display the correct inductance?

Maybe it is all related to the previous post, I just verified that both version have a 10uF capacitors on the input and output of the Vcc regulators.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 26, 2017, 10:14:07 am
You've run into the SamplingADC. It's explained in Karl-Heinz' documentation. The "if 21nF" indicactes a resonant circuit and that the tester expects a 21nF cap in parallel. The frequency is the resonant frequency of the LC circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on June 26, 2017, 09:43:55 pm
@madires, how do you explain the discrepancy between the two testers?

BTW, I read a couple of times Karl-Heinz's "explanation" in paragraph "3.10 Measurement of coils".  unfortunately I have no clue what he was trying to say, maybe in German it made more sense or maybe because I am only an EE.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on June 26, 2017, 09:51:13 pm
@madires, how do you explain the discrepancy between the two testers?
Maybe pcb routing ?just guessing...


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on June 27, 2017, 08:58:53 am
@madires, how do you explain the discrepancy between the two testers?

LCR-T4-H and AY-AT Diy Kits, with 738 revision k firmware and filter capacitors installed in the power supply lines.

I do not notice that difference.

However between version k and m if there are small differences in the measurements.

Attached some pictures of a quick test.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 27, 2017, 09:44:49 am
@madires, how do you explain the discrepancy between the two testers?

I could only guess without having both testers. The first things coming into mind are PCB layout, bypass caps and current draw of the display backlight and hardware options like the Zener test. Those things are the typical causes for strange readings.

BTW, I read a couple of times Karl-Heinz's "explanation" in paragraph "3.10 Measurement of coils" and unfortunately I have no clue what he was trying to say, maybe in German it made more sense or maybe because I am only an EE.

Please see chapter 5.4.2 "Measurement of small inductances with the sampling method".
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 27, 2017, 09:55:34 am
However between version k and m if there are small differences in the measurements.

Of course there are. ;) Most measurement methods got some minor differences and often different ways of compensation. A few methods differ a lot. And the m-firmware doesn't support the SamplingADC (yet?).
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 27, 2017, 05:24:26 pm
@upsss: I'm afraid mine will also be only a guess, but I think that maybe the clamping diodes on the input have something to do with this. If it's not too much trouble, I'd ask you to remove the six-pin package, re-run self-calibration, and then try to measure the same part(s) again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on June 27, 2017, 07:23:22 pm
@hapless, I gave up trying to fix it and I put the AY-AT back in its acrylic case which is a pain in the neck to take apart and put it back together.  I did try to improve the bypassing of the Vcc regulator and the grounding of the processor but nothing helped.  I don't believe it has anything to do with the clamping diodes on the inputs. 

What I think is happening there is that the Vcc regulator is going into current limit when trying to measure inductors with low inductance and low winding resistance.  The way the tester measures inductors is by measuring the current rise time constant through the inductor and calculating the inductance.  I believe the reason that my T3-T4 doesn't exhibit this problem is that it has been heavily modified, see picture.  It is powered by a li-Ion battery with a step up 5V PWM converter which supplies directly the Vcc to the tester.  This 5V output can supply much higher peak current than the original Vcc regulator on the AY-AT tester.  As a result, I believe ALL original testers will exhibit this problem when trying to measure power inductors, basically any inductor with low inductance and low winding resistance.

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 28, 2017, 01:10:33 am
I have two different ones that don't seem to be affected, or maybe my inductors just don't meet the criteria. Mine use the regulator that they came with, no boost converter in sight. Something makes your tester think that there is a capacitor in parallel with the inductor. Something tells me your tester is not the only only doing that. I also think that it could be due to a slight error in calibration...

I'd like to hear Karl-Heinz's take on this, too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 28, 2017, 10:29:52 am
As a result, I believe ALL original testers will exhibit this problem when trying to measure power inductors, basically any inductor with low inductance and low winding resistance.

If Vcc drops too much the MCU's brown-out detection would be triggered. We had that for the Zener test (boost converter) when powered by the same LDO, for example. The low inductance measurement was checked with several different Testers and no issues were found. Of course there could be fringe cases. We can't check all clones and all revisions/versions of each clone. Please add an additional bypass cap and check if the problem is gone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on June 28, 2017, 04:30:56 pm
Any inductor <50uH reads "xxnH if xxnF" any >50uH read fine and it is very consistent.  Otherwise the tester works perfectly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 28, 2017, 04:44:33 pm
What happens if you also put a 21nF cap in parallel with those coils (the one you calibrated with)?

Edit: Is there also a lower limit? I tried with a 300nH coil and still can't reproduce.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 28, 2017, 06:21:01 pm
hapless,here example of measurement of the minimum inductivity - 65nH :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 28, 2017, 06:37:06 pm
Thank you, but I see no anomaly here. You are using a capacitor. upsss is getting "if xxnF" without a capacitor, so the reading is incorrect because the tester is measuring as if there were a tank circuit with a known capacitor. I asked for the minimum value at which this keeps happening.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 28, 2017, 07:00:33 pm
Sorry, but I not absolutely understand why it is necessary?
The resonant method (SamplingADC on) works with excellent accuracy to a upper limit 2-3mH and requires mandatory connection of the capacitor parallel to the measured coil. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 28, 2017, 07:14:46 pm
Because it should not be detecting a capacitor when there is no capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on June 28, 2017, 07:31:31 pm
Because it should not be detecting a capacitor when there is no capacitor.

Woo hoo!  You get free capacitors!
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 28, 2017, 07:36:53 pm
Yep... Too bad they are imaginary.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on June 28, 2017, 07:44:11 pm
Yep... Too bad they are imaginary.

Yes, but an imaginary capacitor is an inductor, so all is well and good and balance has been restored to the force.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on June 28, 2017, 08:00:27 pm
What happens if you also put a 21nF cap in parallel with those coils (the one you calibrated with)?
OK, if I put the 22uH inductor in parallel with my calibration capacitor then I get the correct (~22uH) inductance displayed.  I still don't understand why only the AY-AT tester displays this "xxuH if xxuF" and requires this resonance configuration with the calibration capacitor. Also in case of the 22uH inductor when it display "40nH if 21.3nF" what does the 40nH means?

Another problem, when it displays the inductance correctly like in my example with the 47uH, on the 2nd line it displays some resonant frequency.  In this case it displays 3618kHz, what is the significance of this resonant frequency?  47uH with 21nF (my calibration capacitor) DOESN'T resonates at 3618kHz, it resonates @ ~159KHz, so what is this 3618kHz frequency? 

Any inductor will resonate with any capacitor at some frequency.  What is the significance of knowing the resonant frequency with some arbitrary capacitance, who cares? And who cares what is the Q of that resonant circuit?  Both of these parameters are totally meaningless.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 29, 2017, 07:33:50 am
Also in case of the 22uH inductor when it display "40nH if 21.3nF" what does the 40nH means?

It means that on pins 1-3 tester included measurement by a resonant method and as the capacitor on 21.3nF wasn't connected, incorrectly defined value of inductivity in 40nH. 
Why it included a resonant method without the connected capacitor? It is necessary to understand.
Tester very sensitive in the SamplingADC mode therefore any noises on a supply, the capacity and inductivity of the connected cables create an oscillating circuit.
It is possible to measure inductivity by an old method, connecting a detail on pins 1-2 and 2-3.
Then the resonant method doesn't work, but measuring accuracy of small inductance will be low.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on June 29, 2017, 11:29:57 am
What is the significance of knowing the resonant frequency with some arbitrary capacitance, who cares? And who cares what is the Q of that resonant circuit?  Both of these parameters are totally meaningless.
I will not comment this.. :phew:

I cannot help you regarding the sampling-ADC story 'cause I do not make use of it.
But as far as I know it was introduced by Pieter-Tjerk in mid 2015 and bases on a university project for measuring very small capacities.
Karl-Heinz explained this method in the "Transistortester-AVR" thread within the german "mikrocontroller.net", feel free to ask there for details.
It should be explained in the actual documentation too, my version from 02/2015 is too old ;)

If you don't need to "measure" small caps and inducts don't select this func..;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on June 29, 2017, 01:00:25 pm
I got interested in the SamplingADC Method for measuring small coils and made some tests...
So far it is amazing and finally I got the purpose of the additional capacitor during calibration  :)

To facilitate the measurements with this method I modified my super simple SMD test pads adapter to fit the 20nF capacitor.
Now I'm curious to see how the m-firmware will behave since it doesn't support this methos.

Hey Marcus, thank you again for the development of the Servo test function on the m-firmware.
In this days I used it alot to match few servos and test some ESC for brushless motors I was working on.
To better fit my needs I modifyed the sweep mode of the Servo test in the extras.c file to go all the way from 0.5ms to 2.5ms during sweep (instead of 1ms to 2ms).
If someone is interested I copyed the code below.

Mauro

//Sweep mode Servo test MAX Limits

{
  uint16_t          Temp;     /* temp. value */

  /*
   *  hints:
   *  - the OCF0A interrupt flag is  cleared automatically
   *  - interrupt processing is disabled while this ISR runs
   */

  /* toggle values for PWM */
  #define SERVO_LEFT_MAX     (((CPU_FREQ / 10000) * 5) / 16)   /* 1.0ms */ 
  #define SERVO_RIGHT_MAX    (((CPU_FREQ / 10000) * 25) / 16)   /* 2.0ms */
  //#define SERVO_LEFT_NORM     (((CPU_FREQ / 10000) * 10) / 16)   /* 1.0ms */  //Mauro
  //#define SERVO_RIGHT_NORM    (((CPU_FREQ / 10000) * 20) / 16)   /* 2.0ms */   //Mauro

  /*
   *  update PWM pulse length (Timer1)
   */

  Temp = OCR1B;               /* get current compare value */

  if (SweepDir == 1)          /* forward */
  {
    Temp += SweepStep;        /* add step */

    if (Temp >= SERVO_RIGHT_MAX)  /* exceeded upper limit */    //Mauro
    {
      Temp = SERVO_RIGHT_MAX;     /* limit */               //Mauro
      SweepDir = 2;                /* change direction */
    }
  }
  else                        /* backward */
  {
    Temp -= SweepStep;        /* substract step */

    if (Temp <= SERVO_LEFT_MAX)   /* exceeded lower limit */   //Mauro
    {
      Temp = SERVO_LEFT_MAX;      /* limit */
      SweepDir = 1;                /* change direction */   //Mauro
    }
  }

  OCR1B = Temp;               /* set new compare value */

  #undef SERVO_LEFT_MAX
  #undef SERVO_RIGHT_MAX
  //#undef SERVO_LEFT_NORM   //Mauro
  //#undef SERVO_RIGHT_NORM   //Mauro
}
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 29, 2017, 01:34:07 pm
To facilitate the measurements with this method I modified my super simple SMD test pads adapter to fit the 20nF capacitor.
Now I'm curious to see how the m-firmware will behave since it doesn't support this methos.

Just as a side note, the 664/1284 dev kit got a relay for switching the parallel cap for the SamplingADC automatically. I don't know if Karl-Heinz has added that hardware option already to the firmware. I'm busy with the touch screen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tdriver on July 01, 2017, 04:54:10 pm
I have the ay-at tester, and 2 new 10mH UU9.8 common line filter I measured, show only half the value (5mH , 1.2ohm) why?
everything else seems to work fine.

tester has latest karl-heinz firmware, but Chinese firmware showed the same value.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 01, 2017, 05:49:12 pm
2 * 5mH = 10mH  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: tdriver on July 02, 2017, 05:26:26 am
thank you, I suspected this, but wasn't sure.   :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: scdreger on July 02, 2017, 07:50:58 pm
So I received mine from Amazon (link: https://www.amazon.com/gp/product/B06WW6QNFZ/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1 (https://www.amazon.com/gp/product/B06WW6QNFZ/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1)) yesterday and soldered it up.

The unit turns on (red LED, backlight on display etc.) but the screen appears blank (although lit up). I've read that it could be the contrast setting but I'm not sure how to adjust it blind. I believe you turn it on with a 2 second press to enter menu mode and then keep clicking to move through the different menu items. Can someone tell me how many times to press to get to the contrast setting? Any help would be greatly appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on July 02, 2017, 11:32:01 pm
You should carefully check everything, connections, resistor values, transistors etc. There is no trimpot to adjust the contrast on this version. Make sure the voltages are correct and the microcontroller is connected the right way. If everything is assembled correctly it should work. The contrast can only be changed by software and or compiling the firmware. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 03, 2017, 01:48:52 am
OK, if I put the 22uH inductor in parallel with my calibration capacitor then I get the correct (~22uH) inductance displayed.  I still don't understand why only the AY-AT tester displays this "xxuH if xxuF" and requires this resonance configuration with the calibration capacitor. Also in case of the 22uH inductor when it display "40nH if 21.3nF" what does the 40nH means?
As indman explained, it means that the tester thinks that it sees a coil and a capacitor when there is no capacitor present due to very high sensitivity. The question is, what prompts it to do so? This is why I suspected the protection diodes, as they add capacitance to the input. Also, I see you have a dangling programming header. See if you can fix it so it won't move during measurement. Place it and its cable away from the test points or noise sources.

Another problem, when it displays the inductance correctly like in my example with the 47uH, on the 2nd line it displays some resonant frequency.  In this case it displays 3618kHz, what is the significance of this resonant frequency?  47uH with 21nF (my calibration capacitor) DOESN'T resonates at 3618kHz, it resonates @ ~159KHz, so what is this 3618kHz frequency?
I can't even tell if it's intentional. That line looks like it may be displaying by mistake. This frequency it displays is the resonance of your inductor with the capacitance of your tester's inputs.

Any inductor will resonate with any capacitor at some frequency.  What is the significance of knowing the resonant frequency with some arbitrary capacitance, who cares? And who cares what is the Q of that resonant circuit?  Both of these parameters are totally meaningless.
The frequency display is actually useful. It shows the conditions under which the test was performed. This way, if you insert the same inductor into a different tester that tests under a different frequency, you won't be mislead into thinking that one of the testers is lying to you. I can't comment on the usefulness of knowing Q under a random frequency. There's probably a use case for it, I just can't think of one off the top of my head.

The unit turns on (red LED, backlight on display etc.) but the screen appears blank (although lit up). I've read that it could be the contrast setting but I'm not sure how to adjust it blind. I believe you turn it on with a 2 second press to enter menu mode and then keep clicking to move through the different menu items. Can someone tell me how many times to press to get to the contrast setting? Any help would be greatly appreciated.
The number of menu items depends on the features that were compiled into the firmware. It would probably be easier (and, perhaps, somewhat educational?) to just reprogram the chip.
Title: Re: $20 LCR ESR Transistor checker project
Post by: scdreger on July 03, 2017, 05:44:33 pm
The unit turns on (red LED, backlight on display etc.) but the screen appears blank (although lit up). I've read that it could be the contrast setting but I'm not sure how to adjust it blind. I believe you turn it on with a 2 second press to enter menu mode and then keep clicking to move through the different menu items. Can someone tell me how many times to press to get to the contrast setting? Any help would be greatly appreciated.
The number of menu items depends on the features that were compiled into the firmware. It would probably be easier (and, perhaps, somewhat educational?) to just reprogram the chip.
[/quote]

Thanks for the reply. As I understand it, my Chinese board doesn't allow connection for updates although I think I could use my Arduino to update it. I need to learn how to do that ... I'll look into it.




You should carefully check everything, connections, resistor values, transistors etc. There is no trimpot to adjust the contrast on this version. Make sure the voltages are correct and the microcontroller is connected the right way. If everything is assembled correctly it should work. The contrast can only be changed by software and or compiling the firmware.

Thanks, I double checked everything. I was especially suspicious of the SMDs as that was my first time soldering them, but continuity testing shows each pin or terminal connected to the next point on the PCB.

The only thing I found suspicious was the TL431 showing a dead short between pin 1 and 3,  but I'm a newb so I'm not sure if this is expected behavior. Can someone help me determine if that indicates a problem?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on July 03, 2017, 05:57:04 pm
The only thing I found suspicious was the TL431 showing a dead short between pin 1 and 3,  but I'm a newb so I'm not sure if this is expected behavior. Can someone help me determine if that indicates a problem?

These two pins are supposed to be shorted, that is how you get 2.5v output, see schematic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: scdreger on July 03, 2017, 06:18:32 pm
The only thing I found suspicious was the TL431 showing a dead short between pin 1 and 3,  but I'm a newb so I'm not sure if this is expected behavior. Can someone help me determine if that indicates a problem?

These two pins are supposed to be shorted, that is how you get 2.5v output, see schematic.

Ok thanks for the help and the schematic.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on July 03, 2017, 07:18:24 pm
Please post some pictures  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on July 03, 2017, 07:29:15 pm
So I received mine from Amazon (link: https://www.amazon.com/gp/product/B06WW6QNFZ/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1 (https://www.amazon.com/gp/product/B06WW6QNFZ/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1)) yesterday and soldered it up.

The unit turns on (red LED, backlight on display etc.) but the screen appears blank (although lit up). I've read that it could be the contrast setting but I'm not sure how to adjust it blind. I believe you turn it on with a 2 second press to enter menu mode and then keep clicking to move through the different menu items. Can someone tell me how many times to press to get to the contrast setting? Any help would be greatly appreciated.

Your tester has a color display so it doesn't have a contrast setting.  The contrast setting exist only on mono display like in the T3/T4 version.  As far as reprogramming the processor you either have to remove it and plug into a proper programmer or solder a programming connector as you can see in my picture.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 03, 2017, 08:51:59 pm
Speaking of contrast setting, I just noticed that it appears in the menu (but does nothing, of course) when PCD8544 is used with m firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: scdreger on July 04, 2017, 03:01:18 am
Issue resolved! It turns out I damaged a pad when assembling.  :palm:

One of the ground terminals on the D.C. Jack lifted a pad on the pcb as I inserted it. I had tested for damage, so I thought. Ground traces run on the bottom of the pcb in one direction but on top of the pcb it goes to the center pin of the rotary encoder and continues on from there.

When I was testing resistance to ground all the connections originating from the bottom of the pcb measured .2 ohms/ short but I realized all the ones originating from the top were measuring more than 500K ohms. I soldered in a jumper from the good bottom ground connection directly to the center pin of the rotary encoder and it's fixed.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 04, 2017, 01:10:50 pm
Speaking of contrast setting, I just noticed that it appears in the menu (but does nothing, of course) when PCD8544 is used with m firmware.

The contrast setting for the PCD8544 changes V_LCD, but you're right about nothing's happening. The driver didn't set the maximum value. I have fixed that. Also I agree that you don't need to change V_LCD in most cases. Should we make it an option?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 04, 2017, 08:14:07 pm
VLCD together with temperature compensation can be used for contrast control, but it is possible to fry the LCD that way. But, for as long as you can determine the safety limits, I don't see why it shouldn't be an option.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 07, 2017, 06:04:46 pm
I've just released 1.29m:
- Added touch screen support and driver for ADS7843 compatible touch controllers.
- Fixed bug in contrast setting for PCD8544.
- Fixed silly error in CheckSum().
- Driver for ST7920 based LCD modules with 64x128 pixels.
- Optimized SmallResistor() and changed detecton logic in CheckResistor() to cope better with low value resistances and possible probe contact issues.
- Changed control logic and treshold for Darlington BJTs in Get_hFE_C() to fix issue with some NPN types.
- Global driver for SPI bus. Modified display drivers and configuration accordingly.
- Italian text provided by Gino_09@EEVblog.
- Support for HD44780 with Cyrillic font by hapless@EEVblog.

Touch screen support is meant primarily for ATmega 644/1284 because of the additional IO pins. The display has invisible touch bars at the left, right, top and bottom. The left and top bars act like a rotary encoder being turned anti-clockwise, while right and bottom bars act like a clockwise turn. They also got a speed-up functionality when touched for more than 300ms. The display's center area does the same as the test push button, but it's just a software version (won't power the Zener diode check for example). Of course there's also an adjustment for the touch screen.

A lot of effort went into this new firmware version for moving the SPI communication from the display drivers into a common SPI framework. That was necessary for driving additional SPI clients, and I also had to introduce new configuration options. I've tried to keep the changes simple (added them as aliases in case of bitbang SPI) and hope they'll work for you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on July 08, 2017, 09:35:08 am
Thanks Madires.

Measurement of low-value resistors (less than 1 Ohm) has improved greatly.

It no longer marks a few picofaradios, marks the correct resistance.

I am attaching photos of the LCR-T4-H and the AY-AT Diy Kit.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 10, 2017, 05:39:32 pm
hello everybody,
I just realised something is terrible wrong with my AY-AT compiling :
-so I have just compiled several times 1.29 for AY-AT (7735 LCD) with encoder on PD1/PD3 and I can't just get him measure capacitors.It shows almost double value.
everytime I put inside 1.25 version from trendy it starts measuring correctly,tried with 10 capas (pf,nf,uF).

besides that,the 1,2 and 3 inputs measure almost perfect resistances and identifies transistors.

calibration gives always error!

what i'm doing wrong in your oppinion?
here's the stuff,can anybody test/confirm my fw on ay-at board?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 10, 2017, 07:39:58 pm
Maybe a 16 MHz crystal but firmware compiled for 8 MHz?
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on July 11, 2017, 05:14:09 am
Excellent Job  :) :-+
Color AY-AT 16MHz
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 11, 2017, 07:44:11 am
hello,
you're a genius thanks I made a stupid beginner's mistake.

 you made my day,

best regards, pierre

ps: still have some discrepancies for small capas like those 22 pF for quartz,shows 55-56 avec 1.29 and 26pF avec 1.25m
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 11, 2017, 10:10:21 am
Have you done the adjustment (measure a 220nF - 2.2µF film cap 3 times and then run the self-adjustment via the main menu)? 
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 11, 2017, 11:53:52 am
hi,
did the thing, now pF range seems fine,22pF shows 22 pF !!!
i didn't know that I need to measure something before,I always did calibration after fw upgrade ana cycle power off/on
resistors seems fine too,I checked some 5-6 pieces all around

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: jorgemiguel4 on July 12, 2017, 07:06:24 pm
Hello, I have the TC-1 v2.12k, color TFT version. After a few minutes of using it went dead, opened it and found some bad solder joints in the LCD connection. It's working fine again, except the inductor test that shows wrong DC resistance. 7mH and 150Ohm with a inductor that reads less than 1Ohm in my multimeter. With simple resistors it works fine. Is there anything I can do?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 12, 2017, 11:23:49 pm
Hello all
  I've been working on the latest clone version of the transistor tester project. My PCB is K103603BS and it uses the ST7735 version of the graphic display. I apologize for the crude looking schematic. I wanted to try my hand at drafting the schematic by hand and just went with it at least for now.
   I've been posting a few amateur things on YT and started this little project of sorting out the difference between this clone and the original project schematic. There are a few corrections made to the version I added here versus the first draft from the YouTube post I made. There are probably a few more errors other smarter people will catch as well. I apologize in advance for any errors I have made. Hopefully someone finds this information useful.
https://youtu.be/T8Fl7HL0c0c (https://youtu.be/T8Fl7HL0c0c)

https://drive.google.com/file/d/0Bx7o06dJNau1bzlzOXJhSWFjalk/view?usp=drivesdk
https://drive.google.com/file/d/0Bx7o06dJNau1M0RId2FYTXp4Tk0/view?usp=drivesdk
https://drive.google.com/file/d/0Bx7o06dJNau1OW5CVi1seTVhZnM/view?usp=drivesdk
Title: Re: $20 LCR ESR Transistor checker project
Post by: amspire on July 13, 2017, 12:14:11 am
I did post some PDFs for this board:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1215425/#msg1215425 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1215425/#msg1215425)

The schematic I posted is not perfect - they got the TL431 connections wrong for a start.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 13, 2017, 04:32:31 am
Thanks for that. I am using the original parts designators from the official schematic, with a couple of exceptions namely where I placed C3, and I reused C10 as it is not used on this board.  These designators should maintain any relevant reference information from the official documentation... At least that is my goal. I apologize for missing the previous post. I've read bits and pieces of this thread but 149 pages takes time and a few sessions for me to complete.
Title: gm328 ay-at color display 7735 variant
Post by: perieanuo on July 13, 2017, 09:25:00 am
hi everyone,
I'm working on some COMPLETE and CORRECT (and annotated also) schematic in eagle for the ay-at clone with 7735 graphic display for the members,in order to track the repairings and to setup easily the compiling part.
I'll post soon and dont't shoot me for mistakes,let's put the thing up to date.
and why not add the rest like zener...,change eventually the uP,add tactile,and put up an order for pcb-s

best regards,
pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 13, 2017, 10:23:49 am
   I've been posting a few amateur things on YT and started this little project of sorting out the difference between this clone and the original project schematic. There are a few corrections made to the version I added here versus the first draft from the YouTube post I made. There are probably a few more errors other smarter people will catch as well. I apologize in advance for any errors I have made. Hopefully someone finds this information useful.

Nice video! And don't forget the m-firmware ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 13, 2017, 10:38:33 am
Hello, I have the TC-1 v2.12k, color TFT version. After a few minutes of using it went dead, opened it and found some bad solder joints in the LCD connection. It's working fine again, except the inductor test that shows wrong DC resistance. 7mH and 150Ohm with a inductor that reads less than 1Ohm in my multimeter. With simple resistors it works fine. Is there anything I can do?

The resistance measurement is the same for resistors and inductors. Have you checked other inductors too?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jorgemiguel4 on July 13, 2017, 12:46:54 pm
Hello, I have the TC-1 v2.12k, color TFT version. After a few minutes of using it went dead, opened it and found some bad solder joints in the LCD connection. It's working fine again, except the inductor test that shows wrong DC resistance. 7mH and 150Ohm with a inductor that reads less than 1Ohm in my multimeter. With simple resistors it works fine. Is there anything I can do?

The resistance measurement is the same for resistors and inductors. Have you checked other inductors too?

Yes, I have tried with two similar ones with similar results. The last one read 6.36mH and 148 Ohm while in my multimeter it reads 0.63 Ohm.  Don't know if it matters but both inductors are common mode chokes.

(http://www.feryster.com/polski/images/trafa/uu/UU-10,5.jpg)
Title: AY-AT revised schematics 1st try
Post by: perieanuo on July 13, 2017, 01:37:58 pm

here's the 1st version done with eagle 8.2.2,it's not perfect but quick reference for setup LCD ports, can help
revised TL431 drawing ans proposed LM4040 precision reference, ISP 6 pins header (in fact I have DB9 but it's ugly but simple to implement and good fiability)
eliminated socket and added pads to connect with female bananas on enclosure
SVR05-4 description is not correct,i'll remake the library part or search for a good one


best regards,
pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 13, 2017, 03:21:15 pm
Yes, I have tried with two similar ones with similar results. The last one read 6.36mH and 148 Ohm while in my multimeter it reads 0.63 Ohm.  Don't know if it matters but both inductors are common mode chokes.

That's strange! I've checked a 2.7mH and 22mH common mode choke with the m-firmware an an older k-firmware. The measured values are reasonable.
Title: Re: AY-AT revised schematics 1st try
Post by: jakeisprobably on July 13, 2017, 04:22:18 pm

here's the 1st version done with eagle 8.2.2,it's not perfect but quick reference for setup LCD ports, can help
revised TL431 drawing ans proposed LM4040 precision reference, ISP 6 pins header (in fact I have DB9 but it's ugly but simple to implement and good fiability)
eliminated socket and added pads to connect with female bananas on enclosure
SVR05-4 description is not correct,i'll remake the library part or search for a good one

best regards,
pierre
  I will have to take down my filming setup to get to my desktop and check this out. Alternatively someone could greatly help me out by posting an image. I'd like to integrate or work with you to add this into my current project.
   I am partially disabled, and do all my filming editing and illustrations from an old Samsung Galaxy phone. I am limited to sitting or standing for 1-3 sporadic hours total throughout the day on my good days. This means I'm super slow to complete projects but I can devote a massive amount of time to research editing and creating illustrations.
   I am using the Sketch mobile app (like Microsoft Paint with more layering options) to map out the traces and edit the schematic. I still have and can modify these files easily. I uploaded them to the YT video as streamlined as I could so anyone can visually check my work. I didn't initially plan to add them but it seems like a good resource for all. The only file I can't edit easily is the picture of the PCB with the parts designators. I can remake it if need be but I mistakenly deleted the file this came from while managing my limited storage space.
   I plan to add test points by demonstrating where to bend pins to allow easy test point connections. I also plan to show how to add the ISP header connections. I also want to add pin 1 of the TVS IC to either the Frequency measurement or Voltmeter circuit. The last PCB modification I plan to use on the first stage of this build is to add a trimmer capacitor to replace one of the 22pF caps at the crystal.
  The project will get integrated into an old upcycled enclosure from a HP printer power supply brick. These are easy to pry open with channel locks, and they fit the PCB perfectly while leaving plenty of room for a small transformer and battery.
  If I can figure out the programming side of this device (total ISP noob), I want to add the zener threshold tester, but I plan to use a MC34063 if I go that route.
   ...And if everything goes really well I'd like to look into adding a INA106 differential amplifier with a laser trimmed gain of 10. I was planning to build the milliohm meter from the Scullcom Hobby Electronics YouTube channel, but I think the diff amp might be more useful when integrated into this project. I would probably need help understanding the programming aspects involved to make this happen, but I think this little mod could be interesting.
   The last thing I've been looking into is why "discharged capacitors" are mentioned, but only 'before the device is powered on.' I assume this is due to the TVS IC's need for power. If that's the case, why not simply add a 2 pole normally closed relay to short all 3 test leads with a short on delay circuit powered from the collector of the PNP transistor? Seems like that would solve the problem of mega-burns, but I've not done my research in this area yet.

  The images for Power and Ground test points 1-9 to show in my next YT upload are attached.

 Let me know what you think or if you think I should go in a different direction.
  Thanks, -Jake.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 13, 2017, 11:58:09 pm
Nice video! And don't forget the m-firmware ;)

Thanks for everything Markus. I started reading from the beginning of this thread today trying to read everything you guys have been doing here and elsewhere... WOW!! just wow.
   This thread is much more relevant than I had assumed after seeing bits and pieces other people had linked to.(... and then feeling overwhelmed by the size of this.)
  I tried taking my usual screenshot notes as I read through... I haven't even made it to double digits and already I need to create folders for organizing the range of subjects covered and details I haven't seen elsewhere. This thread needs a wiki or something. I may try to distil my notes from this thread for others at some point.... Although I get the feeling everything I'm saying has been said and done in this thread before ;)
  Thanks again, -Jake.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on July 14, 2017, 04:01:34 am
Hi,

ps hello,
I posted attached first revised schematics for AY-AT clone with 7735 graphical display with some useful annotations
regards,pierre
A quick observation of your schematic, your rotary encoder and its pull-up resistors are drawn wrong.  You are missing the ground connection on the encoder and both sides of it including the pull-ups are shorted.  You should not have lines going through a component like on R7, 8, 9, 10, 13, 15.  Also all junction connections (dots) should be at the actual junction and not somewhere along the line.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 14, 2017, 06:33:20 am

Hi,

ps hello,
I posted attached first revised schematics for AY-AT clone with 7735 graphical display with some useful annotations
regards,pierre
A quick observation of your schematic, your rotary encoder and its pull-up resistors are drawn wrong.  You are missing the ground connection on the encoder and both sides of it including the pull-ups are shorted.  You should not have lines going through a component like on R7, 8, 9, 10, 13, 15.  Also all junction connections (dots) should be at the actual junction and not somewhere along the line.
I corrected encoder ground.also he had a green line in schematic that wasn't a wire but apear like one,modified also.redrawed resistors,but that's just aestethics.
pullups for encoder were correct.
thanks for remarks,pierre

Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on July 14, 2017, 07:25:22 am
The pull-ups do go to the 5v but their other end you have them shorted, R5-R6 are not supposed to be in parallel!  As far as the dots junction, it is not a mistake it is just not a proper way of drawing a schematic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on July 14, 2017, 08:55:31 am
hi everyone,
I'm working on some COMPLETE and CORRECT (and annotated also) schematic in eagle for the ay-at clone
Transistor tester's firmwares are Open Source, original PCB designs/layouts wre Open Hardware!
Why the hell most poeple like to use shittin' closed source programs even in OPEN projects ??
There are OPEN SOURCE variants , too!
Some people like GEDA (Linux), some people like KICAD.
Nowadays KICAD should be first choice.. ;)

This thread needs a wiki or something.
Article AVR Transistortester on mikrocontroller.net (https://www.mikrocontroller.net/articles/AVR_Transistortester#Introduction_.28English.29)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on July 14, 2017, 09:02:43 am
Hi Pierre,
   I had few minutes waiting for a meeting and took the opportunity to play a bit with your schematic, hope you don't mind It was just for fun.
Now the encoder should be fine and I moved few dots in the "proper" position.

Generally speaking I think the issue with the dots is related on how Eagle works.
You should avoid start a junction or a 90degree corner on a component pin.
If you do that, Eagle attach the junction to the component pin and if you move the component you drag the dot junction with it.
I don't like to draw lines or components underneath other components and I moved some wires to avoid it.
I prefer to use the GND simbol and power pin simbol instead of drawing all the wires for the power all around the schematic, but I didn't change that.

Please let me know if was this was helpful.
Enjoy your drawing  :)

Mauro

PS: Why use Eagle? I got used to it and I'm struggling to move to Kikad. For small board it is free, so sometimes for me is just faster to do it in Eagle.
Title: Re: AY-AT revised schematics 1st try
Post by: madires on July 14, 2017, 10:08:19 am
  If I can figure out the programming side of this device (total ISP noob), I want to add the zener threshold tester, but I plan to use a MC34063 if I go that route.

I'd recommend to add a second 5V LDO with proper bypass caps for the boost converter. One of my testers got a MC34063 based boost converter but modules like the MEA 1W series from muRata are more convenient and efficient

   ...And if everything goes really well I'd like to look into adding a INA106 differential amplifier with a laser trimmed gain of 10. I was planning to build the milliohm meter from the Scullcom Hobby Electronics YouTube channel, but I think the diff amp might be more useful when integrated into this project. I would probably need help understanding the programming aspects involved to make this happen, but I think this little mod could be interesting.

Me too. Would be a nice hardware option.

   The last thing I've been looking into is why "discharged capacitors" are mentioned, but only 'before the device is powered on.' I assume this is due to the TVS IC's need for power. If that's the case, why not simply add a 2 pole normally closed relay to short all 3 test leads with a short on delay circuit powered from the collector of the PNP transistor? Seems like that would solve the problem of mega-burns, but I've not done my research in this area yet.

The SRV05-4 is "passive" and doesn't need any supply voltage. And there's aleady a discharge/protection relay add-on. Have you seen Karl-Heinz' excellent documentation ( https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf ) yet?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on July 14, 2017, 12:10:25 pm
I'd recommend to add a second 5V LDO

I preferred a 5V micro switching module.
It can deliver much more current and can be used for:
  - servo test (with the m-firmware)
  - bluetooth module (enabling the serial output on the k-firmware)
  - Zener test (as the input for the boost converter)

I added also a switch to save battery power if this secondary voltage is not in use.
I would add the 3 pin standard header for the servo test and a connector for the serial output (PC3 on the k-firmware).

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: jorgemiguel4 on July 15, 2017, 10:30:24 am
Yes, I have tried with two similar ones with similar results. The last one read 6.36mH and 148 Ohm while in my multimeter it reads 0.63 Ohm.  Don't know if it matters but both inductors are common mode chokes.

That's strange! I've checked a 2.7mH and 22mH common mode choke with the m-firmware an an older k-firmware. The measured values are reasonable.

It may be a problem with this specific model, I found a video review on youtube that shows a inductor test and it seems to have the same issue. See the attachment

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 15, 2017, 05:44:44 pm
To bianchifan:
HI,
just tried kicad.it's the biggest piece of s..eet I ever seen.
I did recomended for someone eagle because it's free and easy to use.dont't need to pass 1 hour to play library parts or digging footprints.
me,i use altium and of course i'll never recommend it,that's other's people job.
and I'm feel free to use everything I consider apropriate to play with this project,even it's payed,windows etcaetera.
btw I was rectified my errors on my first schematic,still one remaining and looking to start a brand new implementation.

you on the other side can use whatever you like without having others on your back.hope you appreciate,it's called FREEDOM of choice,even that means to be stupid to choose payed sw who works by the way almost everytime.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 15, 2017, 05:55:10 pm
Hi Pierre,
   I had few minutes waiting for a meeting and took the opportunity to play a bit with your schematic, hope you don't mind It was just for fun.
Now the encoder should be fine and I moved few dots in the "proper" position.

Generally speaking I think the issue with the dots is related on how Eagle works.
You should avoid start a junction or a 90degree corner on a component pin.
If you do that, Eagle attach the junction to the component pin and if you move the component you drag the dot junction with it.
I don't like to draw lines or components underneath other components and I moved some wires to avoid it.
I prefer to use the GND simbol and power pin simbol instead of drawing all the wires for the power all around the schematic, but I didn't change that.

Please let me know if was this was helpful.
Enjoy your drawing  :)

Mauro

PS: Why use Eagle? I got used to it and I'm struggling to move to Kikad. For small board it is free, so sometimes for me is just faster to do it in Eagle.
Thanks, in fact I was modified my first schematic before that, I left only one little error I was away. I'll move to smd schematics for a complete 328 with my 7735 display.
Tried Kicad , I'll stick to altium.
Best regards

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on July 16, 2017, 10:42:01 am
Quote
Tried Kicad , I'll stick to altium.
Altium is too expensive and, IMHO, just a pain to work with, I've also found it to crash frequently and, although it's been years since I used it, current users tell me it still crashes. 

I've been using Diptrace for years now and it's really nice; there's a trial version that works for 30 days and then I think it pin-limits and the unlimited version is currently $1,195 and worth every penny.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 16, 2017, 10:42:55 pm
Article AVR Transistortester on mikrocontroller.net (https://www.mikrocontroller.net/articles/AVR_Transistortester#Introduction_.28English.29)
   I've read through the English part of that page a couple of times, thanks.
   I am astonished at the history of this project and how different clones have evolved along with the software and fork versions. This was my basis for saying "this needs a wiki." The project is wonderful in it's current configuration/context but the details and evolution of the project deserve their own acknowledgement, in my opinion. A lot of work went into this project to get to it's current iteration. I believe this work should be noticed by everyone not just the few people that have been here all along or the few that read this entire thread history (just a small part of the total project). Also the casual hobbyist or newly interested young kid that grabs an old device off the shelf should be able to understand where their device falls into the mix and what it's capable of. I imagine someone that has an old clone from 2013-2014 has a hard time figuring out what they have and what it is/is not capable of. This thread has lots of older versions I've never seen before.
The SRV05-4 is "passive" and doesn't need any supply voltage.
When a DUT capacitor with a charge is connected, and the test points are connected to a SRV05-4 what exactly causes the failure? Is it simply the potential across the test pins without the completed Vcc to GND loop? I'm mostly confused because of how KH words the warning on the pdf:
Quote
... The Tester may be damaged before you have switched it on. There is only a little protection at the ATmega ports.
   Does the same damage occur regardless of whether the device is on or off?

...there's aleady a discharge/protection relay add-on.
  I read somewhere recently (sorry haven't found the ref), there is a problem, as the circuit is documented. The current draw of the transistor/relay combined with the gain of any BJT transistor pulled too much current. They had mentioned the problem was due to the relay connection at the Vref point. Maybe that person was wrong, I don't know, but the maths looked right to my amateur understanding.
Quote
Have you seen Karl-Heinz' excellent documentation yet?
  Yes, thanks, I've read through everything but the programming section of version 1.13K. I can't promise that I remember every detail but I have read it.
I'd recommend to add a second 5V LDO
I preferred a 5V micro switching module.
It can deliver much more current and can be used for:
  - servo test (with the m-firmware)
  - bluetooth module (enabling the serial output on the k-firmware)
  - Zener test (as the input for the boost converter)
I added also a switch to save battery power if this secondary voltage is not in use.
I would add the 3 pin standard header for the servo test and a connector for the serial output (PC3 on the k-firmware).
Mauro
*sees Bluetooth serial connection//looks though official pdf document again//head explodes*
  You should show that little Bluetooth module mod on your YouTube channel. I'd like to see more about that.

Why would you run 2 linear regulators? Are you guys implying the use of the DC converter to power the transistor tester itself, or am I misunderstanding something else?

When it comes to what I'm doing with the schematic, my goal is to seamlessly integrate this clone version with the current pdf documentation. Ideally I would like to create a final schematic that mirrors figure 2.1 on page 10 of the pdf documentation exactly. I want to fade an image from the KH-original to my clone version seamlessly. This will allow anyone that reads section 2.1 and several other sections, to seamlessly connect what they read to the clone schematic without the need to translate or figure out the differences on their own.
  Every part number will need to match the clone, and every location should should match the schematic while clearly showing the additional parts of the clone's circuit and all designators.

Sorry I have so many questions, hopefully that doesn't offend anyone.

  Thanks for all the help and support,
 -Jake.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 17, 2017, 11:13:56 am
The SRV05-4 is "passive" and doesn't need any supply voltage.
When a DUT capacitor with a charge is connected, and the test points are connected to a SRV05-4 what exactly causes the failure? Is it simply the potential across the test pins without the completed Vcc to GND loop? I'm mostly confused because of how KH words the warning on the pdf:
Quote
... The Tester may be damaged before you have switched it on. There is only a little protection at the ATmega ports.
   Does the same damage occur regardless of whether the device is on or off?

The SRV05-4 is basically a TVS with some additional diodes to hide the TVS' high capacitance from the input/signal lines. There's also a more beefier TVS in parallel in the tester's circuit. Since we can't add series resistors for the analog inputs of the MCU, which would be done usually to limit the current (which could then be handled by the MCU's internal clamping diodes), this input protection is relatively weak. It might take a slap but not a hit. The benefits are no additional current draw like the protection relay, and being smaller and cheaper than the relay. And yes, it doesn't matter if the tester is on or off.

...there's aleady a discharge/protection relay add-on.
  I read somewhere recently (sorry haven't found the ref), there is a problem, as the circuit is documented. The current draw of the transistor/relay combined with the gain of any BJT transistor pulled too much current. They had mentioned the problem was due to the relay connection at the Vref point. Maybe that person was wrong, I don't know, but the maths looked right to my amateur understanding.

The relay circuit works fine, but the caveat is the additional power consumption by the relay.

Why would you run 2 linear regulators? Are you guys implying the use of the DC converter to power the transistor tester itself, or am I misunderstanding something else?

One LDO to power the MCU and the display, and a second one to power the boost converter for the Zener test. The boost converter draws high current at startup (each time you press the test button) which would impact the MCU. Therefore it's better to decouple the boost converter as much as possible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BBBbbb on July 17, 2017, 11:41:43 am
@madires
I've been lurking a bit in this topic but I'm lazy to go thorough all the pages, so what I have to ask you might be already answered somewhere in the topic. In that case I apologize.

Is there a model/version of the meter available for purchase that you prefer/endorse? There are numerous LCR meters on ebay, and from what I understand there is no real cooperation between you and any of them.
You're not interested in maybe trying to initiate some kind of cooperation with someone in Chine, like for example Dangerous Prototypes has with Seeed?

Why am I asking this: Well I'm not willing (better say able) to invest a lot of time into choosing and eventually modding (firmware updating not included) a device that I want to keep on a side for just in case , and would readily pay e.g. 30$ (for otherwise 20$ meter) if I see you recommending that one, and if you get a few bucks for it even better. I'm sure I'm not the only one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 17, 2017, 01:47:43 pm
There's no "official" clone. But if I would buy a tester I'd choose something like the AY-AT kit with a rotary encoder and ST7735 display. I haven't thought about a cooperation with some manufacturer yet. Neither have I received any feedback from a manufacturer so far. If any manufacturer or user likes to support the project, samples of testers (for compatibility), displays (for additional LCD drivers), non-standard components (for improving detection), or maybe T&M devices would be helpful.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 19, 2017, 09:15:26 pm
   I am working on the link history of everything I have found here.
DIY Project Versions from Pages 1-50
Frenchie's Post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg317189/#msg317189)
Moemoe's 1st Post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg319536/#msg319536)
 Moemoe's 2nd Post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg506797/#msg506797)
Fabio Lucca's Post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg674428/#msg674428)
Radio Flash's post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg473116/#msg473116)
Bob808's Post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg706787/#msg706787)
Tom666's Post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg707702/#msg707702)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 20, 2017, 09:06:24 am
What about creating a dedicated thread for your summary?
Title: Re: $20 LCR ESR Transistor checker project
Post by: siri_ on July 23, 2017, 07:49:21 pm
Is there some recommandations about available kits one can buy? I got one that broke and a second one that reads voltage 1V under the real value (and all surface mount).
It would be nice if someone has a recommendation for a kit up-to-date and reliable, prefereably through hole.

Also, is there a way to browse the 140 pages on one page? I am suscribed to another forum where there is this option.Then with ctrl+F it is easy to navigate through and find the information.

Thanks!

EDIT : JEEZ just saw someone asked the same question a couple posts earlier  :palm:

EDIT 2 :
might as well post pictures of mine

(https://thumb.ibb.co/gLChS5/IMG_20170723_160504.jpg) (https://ibb.co/gLChS5) (https://thumb.ibb.co/e4OYZk/IMG_20170723_160522.jpg) (https://ibb.co/e4OYZk)

Hi allI  :-DMM

have one of those, and when I power it from a adjsutable power supply, it says "Bat. 10V OK". But i'm supllying it 9V, at least that's what's my multimeter (uni-t ut61E) says...

Is it something that could be a problem or it doesn't matter?

Thanks!

Sounds very much like a low accuracy resistor in the voltage divider. Does this also happen when you connect a battery?

No problem, it is ok and bear in mind that the values are for indication inly (ie could be way off as you have found)
[...]

I wouldn't say that. If it's way off, the automatic shutoff will not work right, and when running on rechargeable battery power it could mean discharging the battery beyond its limit or using the unit with voltages below the expected 5V on VCC.

And when i plug it to a battery, when i want to turn it on, the screen flickers a bit, but it doesn't turn on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 23, 2017, 09:48:01 pm
Is there some recommandations about available kits one can buy? I got one that broke and a second one that reads voltage 1V under the real value (and all surface mount).
It would be nice if someone has a recommendation for a kit up-to-date and reliable, prefereably through hole.

With so many variations out there, it's kind of hard to make recommendations having not owned them all. Not long ago, it was pretty easy to recommend the red AY-AT version since it had all the bells and whistles and worked fine. Now, it seems there are several variants of it as well. :-//

Quote
Also, is there a way to browse the 140 pages on one page? I am suscribed to another forum where there is this option.Then with ctrl+F it is easy to navigate through and find the information.

Click the Print button at the end of the last post on a page. That will not print the page, but open a printer-friendly version, which also contains all the posts in one stream. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: siri_ on July 23, 2017, 09:58:44 pm
Click the Print button at the end of the last post on a page. That will not print the page, but open a printer-friendly version, which also contains all the posts in one stream. :-+

 :) awesome!!!!

thanks :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: KapIngo on July 24, 2017, 12:50:56 am
I have bought an AYAT on ebay assembled it.. replaced the crystal with 16Mhz also compiled the latest 1.29m in AtmelStudio7 for 16mhz.. everything seems to work fine.. except I cant make the selfAdjustment to work correctly.. I read from madires post that I should measure a 220nF-1uF film capacitor 3 times then do the adjustment test... but everytime I do that an error comes out at the very end instead of done... doing the adjustment without measuring a capacitor completes without error...  also after the adjustment shorting any probes shows 0.01-0.05 ohms instead of 0 homs.. Is this expected or not.. thanks..
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on July 24, 2017, 02:01:27 am
I just bought this direct from taobao.  I think it is most suitable for me at this time.  Last I checked, it was not available on ebay or banggood.  They have an adapter that plugs into the 4mm.  The adapter has a ZIF socket and surface mount pad.

Edit:
This unit could run
https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_st7565_kit

Is there a "m" version readily available for this kit?  Thanks.

Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 24, 2017, 02:48:25 am
Is there some recommandations about available kits one can buy? I got one that broke and a second one that reads voltage 1V under the real value (and all surface mount).
It would be nice if someone has a recommendation for a kit up-to-date and reliable, prefereably through hole.

With so many variations out there, it's kind of hard to make recommendations having not owned them all. Not long ago, it was pretty easy to recommend the red AY-AT version since it had all the bells and whistles and worked fine. Now, it seems there are several variants of it as well. :-//
As far as I can tell there are only 2 common versions of the through hole AY-AT. The board that failed is an oddball surface mount variety of the AY-AT. The 2 common through hole versions are both documented in the Clones section of the current project pdf from KH (https://www.google.com/url?sa=t&source=web&rct=j&url=http://www.avrtester.tode.cz/upload/ttester_en.pdf&ved=0ahUKEwjV9YL58qDVAhUH5IMKHcHqAKoQFggdMAA&usg=AFQjCNHY9LRPTw7S-yJcf8Ch_HzQo2heAg). I ordered the latest version of these myself (w/ ST7735 controller).
   The minimum hardware for this project is an ATmega and 6 resistors. The most common failure is due to damaging the pins of the test leads when testing a capacitor with a charge. Some people have had surface mounted boards that had a bad capacitor on the board in the past, but it was a different version IIRC. Others have had bad solder joints on several occasions.
   If you want a perfect version you could always build your own. There are several links I posted above where others have done this with great results, and the tarball file will get you started.
   I am working on creating an extensive summary of this thread soon, and I'm working on a thorough tutorial on my clone build that I posted on the previous page of this thread, but I'm a gimp and super slow at everything.

Edit: adding picture index 1 of 3 for fun.
https://youtu.be/on1ZrWNt2Us (https://youtu.be/on1ZrWNt2Us)
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 24, 2017, 07:15:08 am
I have bought an AYAT on ebay assembled it.. replaced the crystal with 16Mhz also compiled the latest 1.29m in AtmelStudio7 for 16mhz.. everything seems to work fine.. except I cant make the selfAdjustment to work correctly.. I read from madires post that I should measure a 220nF-1uF film capacitor 3 times then do the adjustment test... but everytime I do that an error comes out at the very end instead of done... doing the adjustment without measuring a capacitor completes without error...  also after the adjustment shorting any probes shows 0.01-0.05 ohms instead of 0 homs.. Is this expected or not.. thanks..
I did the same mistake,it seems you have to measure 3-4 times the capacitor THEn you strart the calibration procedure.
it's well explained in the karl docs but who reads it...

regards,pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on July 24, 2017, 08:09:29 am
I just bought this direct from taobao.  I think it is most suitable for me at this time.  Last I checked, it was not available on ebay or banggood.  They have an adapter that plugs into the 4mm.  The adapter has a ZIF socket and surface mount pad.

Edit:
This unit could run
https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_st7565_kit

Is there a "m" version readily available for this kit?  Thanks.

At Banggood, they call it Hiland DIY M12864 Kit
I preferred this version because it has a nice case and it is faster compared to the latest AY-AT
Attached you can find the m-firmware 1.29 compiled for that hardware (8MHz and 16MHz)
I enabled also the servo function that I use frequently

Have a nice day
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 24, 2017, 10:30:39 am
I have bought an AYAT on ebay assembled it.. replaced the crystal with 16Mhz also compiled the latest 1.29m in AtmelStudio7 for 16mhz.. everything seems to work fine.. except I cant make the selfAdjustment to work correctly.. I read from madires post that I should measure a 220nF-1uF film capacitor 3 times then do the adjustment test... but everytime I do that an error comes out at the very end instead of done... doing the adjustment without measuring a capacitor completes without error...  also after the adjustment shorting any probes shows 0.01-0.05 ohms instead of 0 homs.. Is this expected or not.. thanks..

Before the tester reports an error or success the adjustment values are displayed. Please post those values (with the cap measurements done before the self adjustment).
Title: Re: $20 LCR ESR Transistor checker project
Post by: KapIngo on July 24, 2017, 03:28:50 pm
Before the tester reports an error or success the adjustment values are displayed. Please post those values (with the cap measurements done before the self adjustment).

something had change. If i use a 100nf film capacitor (doesnt show an esr value) and measure 3times success. However if i use a 680nf film capacitor (shows a 0.2ohm esr) and do the adjustment it wont even detect a short.. Just asks create a short circuit, I clicked continue and it shows the eeprom values and then displays an error. If i dont use a capacitor, adjustment will succeed. Attached bellow  are the values detected when it succeeds when using both 100nf capacitor and no capacitor the values are verry similar so i will only upload one image. I cannot upload a value for the 680nf capacitor since it wont even do  the adjustment test anymore its stuck at the create a short display then it displays an error.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 24, 2017, 03:45:13 pm
And if you create the short circuit after the cap measurement before running the self adjustment? The short circuit will trigger the main menu. Simply keep the probes shorted and run the self adjustment
Title: Re: $20 LCR ESR Transistor checker project
Post by: KapIngo on July 24, 2017, 03:57:27 pm
And if you create the short circuit after the cap measurement before running the self adjustment? The short circuit will trigger the main menu. Simply keep the probes shorted and run the self adjustment


thanks madires now it works. If i allow the probe short to enter the menu.

what i did before is. i test the capacitor 3times and then enter the main menu. short the 3probes then finally click the adjustment. That didnt detect a short and created an error.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 24, 2017, 06:58:46 pm
At Banggood, they call it Hiland DIY M12864 Kit
I preferred this version because it has a nice case and it is faster compared to the latest AY-AT
Attached you can find the m-firmware 1.29 compiled for that hardware (8MHz and 16MHz)
I enabled also the servo function that I use frequently

That's the one I got many moons ago. Thanks for the updated files, Mauro. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on July 24, 2017, 07:55:40 pm
Kudos to madires for the amazing effort coding this firmware :-+
Please let me know if it will work on your unit.
Are you currently running the k or m firmware?
Sometimes I think that most of the people that bought this tester don't know they can load 2 different firmware...
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 24, 2017, 08:50:00 pm
I've been running the k firmware that came with the unit. I didn't have extra 328 ICs at the time, but have gotten some since then. So, now I can try newer m and k, as well as upgrade the crystal, while still having the original IC as a backup.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on July 24, 2017, 09:07:51 pm
Don't forget the feses... Most of the time it is the cause of the failed upgrade of this devices.
I had to erase my original IC because it was read protected...
Mauro

Ps: Hi bitseeker!!! Din't noticed it was you. Thank you for your contribution to the forum and the TEA group...
I'm becoming a member  :-DMM   :bullshit: :-BROKE  :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 24, 2017, 11:53:53 pm
Thanks for the fuse reminder. I think I marked a couple of prior posts about them so I'll be sure to get the right ones. Of course, when using the TL866, it's also important to remember which way to set them for "on". It's kind of upside-down.

You're always welcome at the TEA party! :-DMM
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on July 25, 2017, 12:25:14 am
For all the other members that are lost in this 151 pages long thread, i think this is one of the posts you are referring to.
It should be added to the FAQ of the thread  :)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1156375/#msg1156375 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1156375/#msg1156375)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 25, 2017, 04:37:50 am
Part 1
https://youtu.be/on1ZrWNt2Us
Part 2
https://youtu.be/RRJ5K752d18

Just 1 more left :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on July 25, 2017, 08:53:21 am
And if you create the short circuit after the cap measurement before running the self adjustment? The short circuit will trigger the main menu. Simply keep the probes shorted and run the self adjustment

I did the same thing on the LCR-T4-H and the AY-AT DIY Kits, if it is measured in capacitor three times, it enters the menu and autotest is selected, it does not detect the short circuit or it gave error.

The way you comment if it works:

1.- Measure the capacitor three times.
2.- Remove the capacitor, short circuit and make a fourth measurement.
3.- From the menu that appears the autotest is selected and the process is done perfectly.

Thanks Madires.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 25, 2017, 10:39:15 am
I got the same issue with one or two testers from time to time. It's already on my to-do list (with a question mark). Looks like I have to find the cause of this problem now. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 25, 2017, 07:34:27 pm
Found it :) Please add in probes.c in function ShortedProbes() just below

Code: [Select]
  UpdateProbes(Probe1, Probe2, 0);      /* update probes */

following:

Code: [Select]
  ADC_DDR = 0;                          /* set ADC port to HiZ */
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on July 25, 2017, 08:26:13 pm
Found it :) Please add in probes.c in function ShortedProbes() just below

Code: [Select]
  UpdateProbes(Probe1, Probe2, 0);      /* update probes */

following:

Code: [Select]
  ADC_DDR = 0;                          /* set ADC port to HiZ */

Line added to probes.c and perfectly working the autotest on both the LCR-T4-H and the AY-AT Diy Kit.

Checked with several capacitor measurements before, entering the menu, exiting, with the short before and after selecting the autotest, and no fault.

Many thanks Madires.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nitroburn on July 25, 2017, 10:07:24 pm
Having an issue with a AY-AT kit. It does not want to stay powered on after pressing the encoder down. If I keep it held down, it works fine, but cannot be used (it shows menu, does test but cannot select anything while holding encoder down). I've replaced the transistors 9014 x2, 9012 on the left side of the board thinking maybe a transistor was bad, but no help. I've replaced the LED, no help. Changed the software, no help. Not too sure exactly where I should be focusing my attention. It is obviously not doing something involving getting the transistors to hold the on state, which I guess should be done via one of the atmega pins going low(?) after pressing the button to keep it on then high when it shuts off? That is just a complete guess based on pretty much nothing, But I'm not 100% sure of what to look for exactly. I could probably figure it out if I gave it some more time, but I figured I would ask in case someone else has experienced this and already knows the fix, save myself some time.

I don't think I broke anything putting it all together, I did lose the original LED though and I read through the thread and found it is important, however, I tried shorting and replacing it with a couple different LEDs with no help. Any assistance is appreciated. Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: scottie4442 on July 25, 2017, 11:20:27 pm
ok, I have hunted through this tread over and over for the settings to compile the m-firmware (1.29 preferred) for the AY-AT. When I try to use the search feature for AY-AT it tells me there are no matches.  I have tried to read through the last two years of posts but I am missing it. can someone point me to the correct post or give me the correct compiled files, I have the 16mhz crystal installed other than that standard unit.  Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 25, 2017, 11:27:07 pm
scottie4442, mauroh attached m version 1.29 for both clock speeds on the previous page in the following post: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1263842/#msg1263842 (https://www.eevblog.com/forum/testgear/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: nitroburn on July 25, 2017, 11:34:12 pm
ok, I have hunted through this tread over and over for the settings to compile the m-firmware (1.29 preferred) for the AY-AT. When I try to use the search feature for AY-AT it tells me there are no matches.  I have tried to read through the last two years of posts but I am missing it. can someone point me to the correct post or give me the correct compiled files, I have the 16mhz crystal installed other than that standard unit.  Thanks

So do you want to compile the firmware or do you just want the firmware? Search for "winavr" and a bunch of info about compiling should come up. Try searching for the term firmware or compile and a bunch more information should be found easily. Like https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1011926/?topicseen#msg1011926 Searching should give you all you need. It just isn't called AY-AT anywhere on the files you need. For the AY-AT you want the "mega328_color_kit" version of the firmware for the source in the "trunk" folder. for the Markus firmware you have to modify some of the .h files like config.h, config_328.h and possibly makefile to suite your AY-AT.

Pro Tip, if you can't search on the forum, goto google and type "inurl:eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/" And then your search term, like AY-AT. That will give you a million times better results and not be as restricted as the forum search which doesn't index ay-at as a term.

Hopefully that helps.

-edit-
just reread what you wrote and were looking for settings. Still, try the google tip and you will find more relevant results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: scottie4442 on July 25, 2017, 11:34:39 pm
That is for the m12864 model, which I do have one of these and have already downloaded this firmware. My problem is I need it for the AY-AT model, different circuit overall and lcd controller especially. Thanks for the information though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 25, 2017, 11:36:39 pm
Oh, you're right. My bad. I read AY-AT in your post, but my visual memory still went for the m12864 since they look similar (though not identical with the screw terminals, etc.). Well, glad you have an m12864 as well.
Title: Re: $20 LCR ESR Transistor checker project
Post by: scottie4442 on July 25, 2017, 11:43:33 pm
nitroburn -  I could go either way, I do know how to compile it, but not sure what settings in what file needs to be changed/set. If someone already has the firmware compiled for this model, AY-AT or m328 color kit, I would appreciate being able to just download it, would save me a step or two.  What I was searching for is the settings for the m-firmware files for this model.  I have already found the k-firmware files for both of my testers so am good there, I do have a bunch of mega328p's already and wanted to test both firmware version in each model, see which one I liked.  Thanks for all the help so far.

Edit: was reading another post and found the readme and clone files with the setting in it. so I think I can figure it out from here. Thanks for the help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on July 26, 2017, 03:06:49 am
AY-AT 16MHz 
I think I posted the 1.28m firmware around April 25th (8MHz)
.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nitroburn on July 26, 2017, 04:55:46 am
nitroburn -  I could go either way, I do know how to compile it, but not sure what settings in what file needs to be changed/set. If someone already has the firmware compiled for this model, AY-AT or m328 color kit, I would appreciate being able to just download it, would save me a step or two.  What I was searching for is the settings for the m-firmware files for this model.  I have already found the k-firmware files for both of my testers so am good there, I do have a bunch of mega328p's already and wanted to test both firmware version in each model, see which one I liked.  Thanks for all the help so far.

Edit: was reading another post and found the readme and clone files with the setting in it. so I think I can figure it out from here. Thanks for the help.

Most of everything but the display is default. Don't think there was really anything but the screen I had to change. The screen settings are somewhere in this thread but likely could be figured out from the colour kit firmware settings on the trunk software. At least with my AY-AT, but in case i'm wrong, here are some files specific to the AY-AT that might give you a clue as to the settings and also some firmware predone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on July 26, 2017, 06:22:22 am
ok, I have hunted through this tread over and over for the settings to compile the m-firmware (1.29 preferred) for the AY-AT. When I try to use the search feature for AY-AT it tells me there are no matches.  I have tried to read through the last two years of posts but I am missing it. can someone point me to the correct post or give me the correct compiled files, I have the 16mhz crystal installed other than that standard unit.  Thanks

AY-AT Diy Kit Firmware M v1.29m + English + VEXT + Xtal 16MHZ + Check Rotary Encoder + PWM Plus + Fix Autotest.

A greeting.

P.S. Use WinRAR to decompress.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 26, 2017, 06:48:06 am
Having an issue with a AY-AT kit. It does not want to stay powered on after pressing the encoder down. If I keep it held down, it works fine, but cannot be used (it shows menu, does test but cannot select anything while holding encoder down). I've replaced the transistors 9014 x2, 9012 on the left side of the board thinking maybe a transistor was bad, but no help. I've replaced the LED, no help. Changed the software, no help. Not too sure exactly where I should be focusing my attention. It is obviously not doing something involving getting the transistors to hold the on state, which I guess should be done via one of the atmega pins going low(?) after pressing the button to keep it on then high when it shuts off? That is just a complete guess based on pretty much nothing, But I'm not 100% sure of what to look for exactly. I could probably figure it out if I gave it some more time, but I figured I would ask in case someone else has experienced this and already knows the fix, save myself some time.

I don't think I broke anything putting it all together, I did lose the original LED though and I read through the thread and found it is important, however, I tried shorting and replacing it with a couple different LEDs with no help. Any assistance is appreciated. Thanks!

It is not impossible to receive an ATMega that has problems with one port or even one pin. It would be easiest just to try another. Last I checked, pin 12 (PD6) was controlling the on/off state on 328s, so you may want to see what kind of voltages you're getting around the 27k resistors when the tester is off and when the button is pressed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 26, 2017, 09:39:12 am
Settings for a few tester clones are listed in the "Clones" file. If you find any errors or if you've figured out the settings for a clone not listed yet, please let me know. The idea is to help other users by adding settings for all clones.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 26, 2017, 10:04:43 am
Having an issue with a AY-AT kit. It does not want to stay powered on after pressing the encoder down. If I keep it held down, it works fine, but cannot be used (it shows menu, does test but cannot select anything while holding encoder down). I've replaced the transistors 9014 x2, 9012 on the left side of the board thinking maybe a transistor was bad, but no help. I've replaced the LED, no help. Changed the software, no help. Not too sure exactly where I should be focusing my attention. It is obviously not doing something involving getting the transistors to hold the on state, which I guess should be done via one of the atmega pins going low(?) after pressing the button to keep it on then high when it shuts off? That is just a complete guess based on pretty much nothing, But I'm not 100% sure of what to look for exactly. I could probably figure it out if I gave it some more time, but I figured I would ask in case someone else has experienced this and already knows the fix, save myself some time.

I don't think I broke anything putting it all together, I did lose the original LED though and I read through the thread and found it is important, however, I tried shorting and replacing it with a couple different LEDs with no help. Any assistance is appreciated. Thanks!

As hapless already suggested, check PD6 (should be 5V when powered on). Also check the circuit around T3. The type of LED isn't important, only that there's one. I remember a few cases of the PNP having a too low hFE.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 26, 2017, 04:07:54 pm
Has someone already tested (or seen) this Component Tester?
http://www.ebay.com/itm/2016-DIY-Transistor-Tester-LCR-Capacitance-ESR-meter-Frequency-PWM-Generator-/191869802386 (http://www.ebay.com/itm/2016-DIY-Transistor-Tester-LCR-Capacitance-ESR-meter-Frequency-PWM-Generator-/191869802386)
It is available as Kit or already assembled version.

Hi everyone I'm new here... I burn my first module the module above.. I bought another and tried to clone the ic.. but I think is lock I have tried all firmware  that you guys provide in the post so far non works. I found one in YouTube but it was Russian and I don understand... Anyone care to help or have the firmware...  I'll be very thankful if you share it....

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 26, 2017, 04:13:29 pm
Has someone already tested (or seen) this Component Tester?
http://www.ebay.com/itm/2016-DIY-Transistor-Tester-LCR-Capacitance-ESR-meter-Frequency-PWM-Generator-/191869802386 (http://www.ebay.com/itm/2016-DIY-Transistor-Tester-LCR-Capacitance-ESR-meter-Frequency-PWM-Generator-/191869802386)
It is available as Kit or already assembled version.

Hi everyone I'm new here... I burn my first module the module above.. I bought another and tried to clone the ic.. but I think is lock I have tried all firmware  that you guys provide in the post so far non works. I found one in YouTube but it was Russian and I don understand... Anyone care to help or have the firmware...  I'll be very thankful if you share it....

Thanks

hi,
just write ay-at 1.29 hex+eep file with right fuses it works 100% you find it 1-2 pages before
if it didn't work you have a hardware pb
regards pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 26, 2017, 04:19:16 pm
Hi thanks...

 But mine uses 1.12k will it work?

 By the way about the fuses which fuses should I use?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 26, 2017, 05:08:04 pm
hello everybody,
I just realised something is terrible wrong with my AY-AT compiling :
-so I have just compiled several times 1.29 for AY-AT (7735 LCD) with encoder on PD1/PD3 and I can't just get him measure capacitors.It shows almost double value.
everytime I put inside 1.25 version from trendy it starts measuring correctly,tried with 10 capas (pf,nf,uF).

besides that,the 1,2 and 3 inputs measure almost perfect resistances and identifies transistors.

calibration gives always error!

what i'm doing wrong in your oppinion?
here's the stuff,can anybody test/confirm my fw on ay-at board?

hi pierre,

is this the post you meant. yes my tester would turn on but keep testing and won't go to menu...

i guess something is wrong with the firmware, might be incompatible.

nicho
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 26, 2017, 05:56:28 pm
here you have all for 20 mhz quartz
just write ant calibrate
regards,pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 26, 2017, 06:26:25 pm
... I tried to reprogram the chip using the files from mega328_st7565_kit ...

For your tester (with TFT display) is designed firmware in the folder "mega328_color_kit".
You can use the firmware from the attached zip file.

yes...

finally this firmware work for me.. bu it's release 681

anyone have the final version of this

thanks

Nicho
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 26, 2017, 06:31:55 pm
here you have all for 20 mhz quartz
just write ant calibrate
regards,pierre


thanks for the effort Pierre but mine is 8 not 20mhz.

manage to find one that work, like i said in my last post, but it's 1.12k  681.

but will yours work?

I"ll try that

thanks

Nicho



Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 26, 2017, 07:00:10 pm
here you have all for 20 mhz quartz
just write ant calibrate
regards,pierre

Hi Pierre,

i tried your firmware, it's nice but i guess it don't work because your is 20 mine is still 8 mhz

but i'll would be nice if you can make the 8

thanks

Nicho
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on July 26, 2017, 09:13:49 pm
You can download the K versions for the different hardware already compiled from the SVN repository:
svn://mikrocontroller.net/transistortester
The newest K version is 1.13K
For the m versions you have to compile them yourself.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nitroburn on July 27, 2017, 12:00:09 am
It is not impossible to receive an ATMega that has problems with one port or even one pin. It would be easiest just to try another. Last I checked, pin 12 (PD6) was controlling the on/off state on 328s, so you may want to see what kind of voltages you're getting around the 27k resistors when the tester is off and when the button is pressed.

Thanks for the suggestions, I have tried multiple atmegas so its most likely a circuit issue. I'll do a bit more poking and prodding to see what I come up with.
As hapless already suggested, check PD6 (should be 5V when powered on). Also check the circuit around T3. The type of LED isn't important, only that there's one. I remember a few cases of the PNP having a too low hFE.

Will do, thanks for the suggestions. There are a few transistors there, which one had too low hFE in the cases you speak of? I have replaced them all except 7550 as I didn't have any of those around, but plenty of others.


-edit-
Well if I short the two right pins on the 9014 directly below the LED, it acts like it should on power up with LED on and all plus menus and testing, but removing the short promptly kills it again. The 9012 almost half way down the board shorting the right two pins turns it on as well, but without the LED and it dies on removal. Guess I'll try replacing a few more capacitors and testing the components off the board. I'll have to look a little more in-depth at the power side of the schematic and trace things back part by part. I don't want to throw my hands up and solder a switch.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 27, 2017, 05:27:30 am
You can download the K versions for the different hardware already compiled from the SVN repository:
svn://mikrocontroller.net/transistortester
The newest K version is 1.13K
For the m versions you have to compile them yourself.

hi Casinada,

fyi i'm new. sorry if i asked a stupid question  how do i compile a new firmware? what do i need or where can i get a good guide. i have been reading here and there. maybe because i'm new to this just don't really understand.

i already install atmel studio, winavr, avrdudess, anything else i need?

thanks

N1cho
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 27, 2017, 05:53:02 am
you have 1.29m compiled for 8m,test and feedback please
regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 27, 2017, 09:20:37 am
On my main AY-AT (color kit) Transistor tester I use the SVN700 version from member STJ.
It works very well and has both 8MHz and 16MHz files in the archive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: maus on July 27, 2017, 09:51:41 am
As first. Hi to all!
I bought the the LCR ESR Transistor checker with just the TEST pushbutton, an I discovered just yesterday night the availability of frequency, function generator and other features. They appears to be activated by momentary BUTTON TEST actions, but very hard to activate.
How can I hack the circuit by adding the rotatory switch, also integrating / removing the test button?
Thanks to all in advance
Maurizio Maurizi
Title: Re: $20 LCR ESR Transistor checker project
Post by: jm_araujo on July 27, 2017, 10:57:40 am
You can find the original manual for the k version  in here: https://github.com/svn2github/transistortester/raw/master/Doku/tags/english/ttester_eng112k.pdf

Schematics are included and it shows how to connect a rotary encoder in section 2.2.5, page 13/14.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 27, 2017, 12:42:31 pm
@maus: Perhaps you can use the ideas from:
http://www.badcaps.net/forum/showthread.php?t=50720&highlight=transistor+tester (http://www.badcaps.net/forum/showthread.php?t=50720&highlight=transistor+tester)

Where STJ describes the modification by adding a rotary encoder to the EZM GM328 tester.
This modification works well, but needs also a firmware update to enable the rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 27, 2017, 05:38:34 pm
I've been using Karl-Heinz firmware on my tester (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=240350).
But today I felt I should try Markus firmware on it, however I can't get the encoder to behave properly.
I have tried setting "ENCODER_PULSES" to 1,2 & 4 but it moves erratically.
If I am very careful moving one indentation while in PWM mode it will count 2 steps no matter what I set "ENCODER_PULSES" to.
That is to say one indentation seems to correspond to two pulses.
If I however turn it at a "normal slow" speed it will go very fast, probably due to the double signals?
My encoder has 24 physical indentations or steps which I've set in "ENCODER_STEPS"
What can I do to troubleshoot this further, any more info I can provide?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 27, 2017, 05:54:12 pm
I just finished part 3.
     Use this as a visual index reference. If you want to find where someone posted a reference to a problem or project in the past, these 3 index videos should help you find the page number visually.
    There are over 700 images total here. If anyone knows a good way for me to upload these pictures from an Android device to another website please let me know soon so I can do this before deleting them for space. I manually renamed them by their thread page numbers so the archive is very useful. I have removed some duplicates after I created these 3 uploads. I kept almost all pictures in these 3 so that you can visually identify every time a certain clone is discussed. I have also added a few pictures from links about the project that were posted and seemed interesting. Hopefully you find this helpful and interesting.
   If your new to this thread, are having problems with your device, or haven't gone through the whole thread, this will help you find interesting ideas highlights to look up on different pages, or others that have had the same problem as you. Everything worthwhile in this thread is accompanied by pictures.
Part 1
https://youtu.be/on1ZrWNt2Us
Part 2
https://youtu.be/RRJ5K752d18
Part 3 (new)
https://youtu.be/1ARlc1BHLUw

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 27, 2017, 06:03:39 pm
My encoder has 24 physical indentations or steps which I've set in "ENCODER_STEPS"
What can I do to troubleshoot this further, any more info I can provide?

I'd guess your rotary encoder got 4 Gray code pulses per detent (ENCODER_PULSES  4). Have you set ENCODER_A and ENCODER_B (config_328.h) to match your tester?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 27, 2017, 06:14:17 pm
madires: Yes this is what I have right now:

#define ENCODER_PULSES   4
#define ENCODER_STEPS    24
#define ENCODER_A        PD1
#define ENCODER_B        PD3
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 27, 2017, 06:36:05 pm
Could you please also post your display settings?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 27, 2017, 07:00:42 pm
Sure, this is what I've used:
Code: [Select]
/*
 *  ST7565R, SPI interface (bit-bang)
 *  - settings for Electronic Assembly EA DOGM/DOGL128-6
 *  - uses LCD_CS to support rotary encoder in parallel at PD2/3
 */

//#if 0
#define LCD_ST7565R
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD0            /* port pin used for /RES (optional) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
//#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_OFFSET_X                    /* enable x offset of 4 dots */
//#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     22             /* default contrast (0-63) */
#define FONT_8X8_VF                     /* 8x8 font, vertically aligned & flipped */
#define SYMBOLS_24X24_VFP               /* 24x24 symbols, vertically aligned & flipped */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SI         /* port pin used for MOSI */
//#endif
On the LCD itself is this writing: LCM_12864_V1.30
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 27, 2017, 07:30:04 pm
Ok, just wanted to check if there's a possible issue with the display in parallel with the rotary encoder. I don't have any further ideas at the moment. Sorry!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 27, 2017, 08:27:02 pm
Ok thanks, I changed the direction of the encoder like so:
Code: [Select]
#define ENCODER_A        PD3
#define ENCODER_B        PD1
And then the error with moving it very slowly resulting in two counts disappeared.
Isn't that quite strange? I thought the direction error would just be a nuisance, not actually cause a real fault?
I.e. this problem no longer exists:
"If I am very careful moving one indentation while in PWM mode it will count 2 steps no matter what I set "ENCODER_PULSES" to."

Anyway after that has been done my error feels quite similar to that reported by mauroh linked below.
So I tried downgrading from v1.29 to v1.27 but there was no difference in behavior.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1144496/#msg1144496 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1144496/#msg1144496)

And just to be clear the issue is not only in PWM mode or Servo mode, even navigating the menu is difficult...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 27, 2017, 09:28:44 pm
Is it the same for ENCODER_PULSES 2 and 4?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 27, 2017, 10:41:18 pm
With ENCODER_PULSES set to 4 I can not get the tester to misbehave if I turn the encoder very slowly.
But with it set to 2 this behavior exists: "If I am very careful moving one indentation while in PWM mode it will count 2 steps"
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 28, 2017, 04:16:36 am
you have 1.29m compiled for 8m,test and feedback please
regards


Thanks

yes it work this time.  Nice. the selfttest does not need 100pf caps and others just need to short 1,2,3.

thanks


Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 28, 2017, 07:43:27 am
hi guys,
that's incredible they did it for 11.68 usd just the case missing,testers included,battery holder also.
how did they can produce this low?in this price you have the raw hardware,transport,seller value...
i know that's no new theme for anybody,but still surprise me!
i'd wish I can sell something like that in france at that price and still be in profit.wtf,even in romania...

http://www.ebay.com/itm/3-7V-of-inductor-capacitor-ESR-meter-DIY-MG328-multifunction-transistor-tester-C-/322546300660?hash=item4b1941f6f4:g:GyMAAOSws5pZOBXP (http://www.ebay.com/itm/3-7V-of-inductor-capacitor-ESR-meter-DIY-MG328-multifunction-transistor-tester-C-/322546300660?hash=item4b1941f6f4:g:GyMAAOSws5pZOBXP)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 28, 2017, 10:28:31 am
yes it work this time.  Nice. the selfttest does not need 100pf caps and others just need to short 1,2,3.

You get a penalty point for not reading the README file. >:D Please measure a film cap about 220nF up to 2.2µF three times before running the self adjustment for getting the offsets of the bandgap reference and analog comparator.

BTW, there's a hardware option for a fixed self adjustment cap for the ATmega 324/644/1284. In that case the offsets mentioned above are measured during the adjustment automatically.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 28, 2017, 10:41:45 am
With ENCODER_PULSES set to 4 I can not get the tester to misbehave if I turn the encoder very slowly.
But with it set to 2 this behavior exists: "If I am very careful moving one indentation while in PWM mode it will count 2 steps"

You can also play with ENCODER_STEPS to change the feedback. A higher value slows down the rotary decoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 28, 2017, 11:40:25 am

You can also play with ENCODER_STEPS to change the feedback. A higher value slows down the rotary decoder.
I used 30 for ay-at clone seemed good enough for my encoder


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 28, 2017, 12:14:29 pm
You can also play with ENCODER_STEPS to change the feedback. A higher value slows down the rotary decoder.
I tried 30 and 48 without seeing that much difference TBH.
It's strange that it works quite well with Karl-Heinz firmware.
Otherwise I would suggest a hardware defect with the encoder.
Perhaps it still is, and his just happens to be a little less sensitive to the signal?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 28, 2017, 01:28:52 pm
A while ago I bought a bunch of the cheapest Chinese rotary encoders I could find for testing the read algorithm. One or two types were a little bit dicky, but still ok. The read algorithm enforces a proper Gray code sequence, no just reading one signal and then checking the second one to get the direction. The diameter of the knob is also important, since a larger diameter provides better control. The ENCODER_STEPS setting is meant to allow to finetune the feedback and to compensate the knob's diameter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 28, 2017, 10:13:44 pm
My very first tester with the rotary encoder and frequency counter options:
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=297782;image)

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=297784;image)

I have been researching this thread for weeks and I'm just getting into the last 50 pages in depth. The biggest mystery I have found in this entire thread:
 I have no idea why this post went largely unquestioned.

  First of all, kudos on the best looking custom designed project build and execution here. No one can call this a "cheap build." Regardless of cost this thing is NICE!
   From what I see, there are a few too many potentiometers, transistors, and unexplained extras like a whole extra IC on this bad boy. Maybe my eyes are messing with me but...are those RF choke beads I'm seeing on a few component leads? I think you've got some explaining to do here Mr Markus :) Especially on that little lie you've been spreading about how your a "Qualified Hobbyist." Your a pro at understating yourself and being respectful of everyone here despite repeating yourself a hundred times over to fools like me.
   I'm onto you though, only the most experienced top notch professionals create such a masterful execution of a project like this....and from the statement, "my very first tester with the rotary encoder and frequency counter" I'm going to go ahead and assume there are others before and after this! Sign me up for your masters class please. What would it take to get you to explain some of your unpublished tricks and mods?
:-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 28, 2017, 11:01:57 pm
Hehe, don't mess with the master! :-+

Additional enclosures and related mods also at https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/ (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 29, 2017, 02:54:51 am
Additional enclosures and related mods (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/)
   Oh I know :-) I have been putting together a whole lot more than what I have posted here already. The picture index is really a tool for me to break down this entire thread into something much easier to use. I have a content index I've been working on as well but that is much harder to share in raw form like pictures.

 I will add a collection of content to the enclosures thread soon. I've been building that file for a few days in parallel with others.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 29, 2017, 05:36:08 am
Just a bit of a heads-up: Some images that are linked from the posts here may be copyrighted or otherwise protected. You may wish to check that before including them into anything you publish just to be on the safe side.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 29, 2017, 10:35:44 am
hi everyone,

i hope someone can help me out again.

i have a 2nd unit of this transistor tester that works with m328 colour kit firmware. but this unit is totally off and would not switch on at all. i have change the atm328 ic but still will not turn on. i tested all the R no problem the caps also all well. i test the s9014, s9012, tl431 and HT7550 but i think the HT7550 is the problem (attached) i look for the part but n/a can it be replace with 78L05. can it be other parts that cause the problem

thanks

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 29, 2017, 11:06:29 am
  First of all, kudos on the best looking custom designed project build and execution here. No one can call this a "cheap build." Regardless of cost this thing is NICE!

Thanks! I'm flattered ;)

   From what I see, there are a few too many potentiometers, transistors, and unexplained extras like a whole extra IC on this bad boy. Maybe my eyes are messing with me but...are those RF choke beads I'm seeing on a few component leads? I think you've got some explaining to do here Mr Markus :)

It's nothing fancy, and you can find the schematics and PCB layouts in the SVN/git repo. That tester has a LM339 based PWM control for the LCD backlight. The potentiometer on the left is for the LCD's contrast, and on right is another one for the PWM. The PCB layout is designed for DYI, because the best tester is the one you've built yourself :) There aren't any ferrite beads. Originally that tester had a simple "test" push button which was replaced by a rotary encoder later on. The small PCB attached to the LCD is for the rotary encoder and frequency counter. The third potentiometer adjusts the sensitivity of the frequency input (in parallel with LCD's RS signal line).

Especially on that little lie you've been spreading about how your a "Qualified Hobbyist." Your a pro at understating yourself and being respectful of everyone here despite repeating yourself a hundred times over to fools like me.

Actually it's the truth :) I got a degree in EE but went into network architecture/engineering while doing EE as a hobby. Hence the "qualified hobbyist".

   I'm onto you though, only the most experienced top notch professionals create such a masterful execution of a project like this....and from the statement, "my very first tester with the rotary encoder and frequency counter" I'm going to go ahead and assume there are others before and after this!

It's really my very first Transistor Tester, followed by a few more of course. Also I got some testers and PCBs from users in Ukraine and Russia (Karl-Heinz shared them with me. He's a nice guy too!).

Sign me up for your masters class please. What would it take to get you to explain some of your unpublished tricks and mods?
:-)

A true magician never reveals his secrets ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 29, 2017, 11:13:45 am
i have a 2nd unit of this transistor tester that works with m328 colour kit firmware. but this unit is totally off and would not switch on at all. i have change the atm328 ic but still will not turn on. i tested all the R no problem the caps also all well. i test the s9014, s9012, tl431 and HT7550 but i think the HT7550 is the problem (attached) i look for the part but n/a can it be replace with 78L05. can it be other parts that cause the problem

Thou shall measure voltages! ^-^ Check Vcc when the rotary encoder is pressed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on July 29, 2017, 11:58:02 am
hi everyone,

i hope someone can help me out again.

i have a 2nd unit of this transistor tester that works with m328 colour kit firmware. but this unit is totally off and would not switch on at all. i have change the atm328 ic but still will not turn on. i tested all the R no problem the caps also all well. i test the s9014, s9012, tl431 and HT7550 but i think the HT7550 is the problem (attached) i look for the part but n/a can it be replace with 78L05. can it be other parts that cause the problem

thanks

I just repaired mine that was the same (dead) and was wrong T1 (S9012), replaced by an equivalent and working

Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 29, 2017, 03:53:04 pm
Here is how to setup a build environment on CentOS7 or RHEL7 (Red Hat Enterprise Linux)
In the optional repository EPEL (https://fedoraproject.org/wiki/EPEL) we have already avr for our purposes.
The version provided is avr-gcc 4.9.2 (http://ftp.acc.umu.se/mirror/fedora/epel/7/x86_64/a/) which unfortunately produces files that are a little bigger than the previous release.
So if you are not on the limit size wise this version will work fine, but if not read on.

So since an older version is not available for CentOS7 on EPEL we have to try to find one.
Looking around (https://rpms.remirepo.net/rpmphp/zoom.php?rpm=avr-gcc) we can see that for Fedora 19 avr-gcc 4.8.2 was released.
This is perfect because Fedora 19 is the same baseline system as RHEL7.
So login as a standard user on your Centos7 or RHEL7 machine and lets rebuild this source RPM:

Code: [Select]
wget http://archive.fedoraproject.org/pub/archive/fedora/linux/updates/19/SRPMS/avr-gcc-4.8.2-2.fc19.src.rpm
wget http://archive.fedoraproject.org/pub/archive/fedora/linux/releases/19/Everything/source/SRPMS/a/avr-libc-1.8.0-4.fc19.src.rpm

rpmbuild --rebuild avr-gcc-4.8.2-2.fc19.src.rpm
rpmbuild --rebuild avr-libc-1.8.0-4.fc19.src.rpm

su root -c "rpm -ivh /home/per/rpmbuild/RPMS/x86_64/avr-gcc-4.8.2-2.el7.centos.x86_64.rpm /home/per/rpmbuild/RPMS/noarch/avr-libc-1.8.0-4.el7.centos.noarch.rpm"
Replace /home/per with your user used for building.
Happy building :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 29, 2017, 05:45:24 pm
hi everyone,

i hope someone can help me out again.

i have a 2nd unit of this transistor tester that works with m328 colour kit firmware. but this unit is totally off and would not switch on at all. i have change the atm328 ic but still will not turn on. i tested all the R no problem the caps also all well. i test the s9014, s9012, tl431 and HT7550 but i think the HT7550 is the problem (attached) i look for the part but n/a can it be replace with 78L05. can it be other parts that cause the problem

thanks

I just repaired mine that was the same (dead) and was wrong T1 (S9012), replaced by an equivalent and working



i have replace 9014, 9012, tl431 but not the HT7550, putting the original HT7550 it does not have 5v out and s9012 heated up. i guess 7550 is the problem.

anyways back to my other unit. those anyone have firmware like the original i have the menu is:

1. Switch off
2. Transistor test
3. Frequency test
4. f-Generator
5. 10-bit PWM
6. C+ESR@TP1:3
7. continuous measurement resistance
8. 1-||-3 continuous measurement capacitance
9. Rotary encoder
10. SelfTest
11. Voltage test
12. FrontColor
13. BackColor adjust
14. Show data

pierre firmware works on mine but his does not have voltage test, i know the voltage test goes only up to 50v, but my module have the voltage test port.

pierre firmware menu are
pwm
zener
esr
freq counter
rotary encoder
ir detection
opto coupler ( what is this for?)
selftest
adjustment
save
load
show values
exit

when testing resistance why my module have 2 value the test point 2 is empty but there is value too. test point 1 and 3 show the correct resistance value . is there something wrong?

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on July 29, 2017, 08:51:39 pm
BTW, there's a hardware option for a fixed self adjustment cap for the ATmega 324/644/1284. In that case the offsets mentioned above are measured during the adjustment automatically.

Sorry, could you please explain, which hardware option?
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 29, 2017, 08:55:03 pm
hi everyone,

i hope someone can help me out again.

i have a 2nd unit of this transistor tester that works with m328 colour kit firmware. but this unit is totally off and would not switch on at all. i have change the atm328 ic but still will not turn on. i tested all the R no problem the caps also all well. i test the s9014, s9012, tl431 and HT7550 but i think the HT7550 is the problem (attached) i look for the part but n/a can it be replace with 78L05. can it be other parts that cause the problem

thanks

I just repaired mine that was the same (dead) and was wrong T1 (S9012), replaced by an equivalent and working



i have replace 9014, 9012, tl431 but not the HT7550, putting the original HT7550 it does not have 5v out and s9012 heated up. i guess 7550 is the problem.

anyways back to my other unit. those anyone have firmware like the original i have the menu is:

1. Switch off
2. Transistor test
3. Frequency test
4. f-Generator
5. 10-bit PWM
6. C+ESR@TP1:3
7. continuous measurement resistance
8. 1-||-3 continuous measurement capacitance
9. Rotary encoder
10. SelfTest
11. Voltage test
12. FrontColor
13. BackColor adjust
14. Show data

pierre firmware works on mine but his does not have voltage test, i know the voltage test goes only up to 50v, but my module have the voltage test port.

pierre firmware menu are
pwm
zener
esr
freq counter
rotary encoder
ir detection
opto coupler ( what is this for?)
selftest
adjustment
save
load
show values
exit

when testing resistance why my module have 2 value the test point 2 is empty but there is value too. test point 1 and 3 show the correct resistance value . is there something wrong?

thanks
Sorry.
If I don't forget I'll recompile one Monday with all stuff activated.I was almost sure voltage measurement is on...I'll check.
Regards Pierre


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 29, 2017, 08:58:26 pm
BTW, there's a hardware option for a fixed self adjustment cap for the ATmega 324/644/1284. In that case the offsets mentioned above are measured during the adjustment automatically.

Sorry, could you please explain, which hardware option?
I think we have to mount a capacitor on the pcb and recompile with new option capacities bla bla bla.so the Uc knows he has an installed capacitor and do the calibration accordingly.
I'm wrong?
Regards Pierre


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 29, 2017, 09:29:18 pm
BTW, there's a hardware option for a fixed self adjustment cap for the ATmega 324/644/1284. In that case the offsets mentioned above are measured during the adjustment automatically.

Sorry, could you please explain, which hardware option?

A 470k resistor, a film cap (100nF up to 1000nF), an analog input and an I/O pin for switching the resistor. IIRC, it's in the 644 circuit in Karl-Heinz' documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 30, 2017, 02:06:17 am
BTW, there's a hardware option for a fixed self adjustment cap for the ATmega 324/644/1284.....
...A 470k resistor, a film cap (100nF up to 1000nF), an analog input and an I/O pin for switching the resistor. IIRC, it's in the 644 circuit in Karl-Heinz' documentation.

Page 131 of this thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 30, 2017, 06:10:18 pm
By the way looking at the spec for capacitor measurement it start 25pf my module...  Anyone start from 1pf, i found 1 module start from 3pf-1mf. According to schematic program do the measurement, is it?

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Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 30, 2017, 06:26:37 pm
k-firmware: 25pF - 100mF
m-firmware: 5pF - 100mF

100mF is the theoretical upper limit (we've tested up to about 20mF).
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 31, 2017, 07:18:27 am
1.29M compilated with zener activated (voltage) for 8-16-20 mhz
seems to measure with some wrong offset (mine showed 9.9V for 9V input!!) haven't time to dig the voltage issue;anyway others seems fine (rcl,transistors).
if fact the only modif was zener activation,i never use this,just put my supply in crt limitation and a in-rush res and see the zener on my fluke,the 328 is for semiconductors and capacitors/inductances
next time i'll let you pay with winavr or another compiler,it's really easy
the 20 mhz is tested on my ay-at
regards,pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 31, 2017, 10:33:02 am
1.29M compilated with zener activated (voltage) for 8-16-20 mhz
seems to measure with some wrong offset (mine showed 9.9V for 9V input!!) haven't time to dig the voltage issue;anyway others seems fine (rcl,transistors).
if fact the only modif was zener activation,i never use this,just put my supply in crt limitation and a in-rush res and see the zener on my fluke,the 328 is for semiconductors and capacitors/inductances
next time i'll let you pay with winavr or another compiler,it's really easy
the 20 mhz is tested on my ay-at
regards,pierre
Thanks i'll try it again...

Anyway... Anyone knows what does the ic svr5-04 do... My other unit which i mentioned above that is dead.. point out to that ic.. that fail.. making 9012, 7550 9014 to heat up...

Thanks

Sent from my E39 using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on July 31, 2017, 11:40:12 am
Anyone knows what does the ic svr5-04 do... My other unit which i mentioned above that is dead.. point out to that ic.. that fail.. making 9012, 7550 9014 to heat up...
Thanks

It is a protection. Remove it and try the tester again. I would not bother replaciing it.
I much prefer the relay protection.
It will work or you will move to the next faulty component :)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on July 31, 2017, 12:01:46 pm
Anyone knows what does the ic svr5-04 do... My other unit which i mentioned above that is dead.. point out to that ic.. that fail.. making 9012, 7550 9014 to heat up...
Thanks

It is a protection. Remove it and try the tester again. I would not bother replaciing it.
I much prefer the relay protection.
It will work or you will move to the next faulty component :)

Mauro
Thanks for your replay.

I have remove it. yet.. the LCD only turn on if the rotary switch is press..  lcd all white, led not on..  those below the led ,9012, 9014 ,7550. Heat up...

After the svr5-04 remove must i solder across or leave it?

All other components have been tested.. the 328p ic tested fine on other unit..



Sent from my E39 using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on July 31, 2017, 01:25:57 pm
Remove the microcontroller. If you know it is working, try to fix everything else before placing it.
Check the Led (also the orientation if you have removet to test it) and assuming we are talking about the attached schematic, remove D3.
It is another protection that could be damaged, again I would not bother replacing it.
While you press the encoder, measure VBat (see the label on the schematic), if it is OK, measure the voltage on pin 7 of the microcontroller socket.
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 31, 2017, 05:49:24 pm
@N1cho:
Maybe it's time to break out your continuity tester. ...because this can happen:
https://www.youtube.com/watch?v=4AN6rInz5s8 (https://www.youtube.com/watch?v=4AN6rInz5s8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on July 31, 2017, 06:02:21 pm
Quote from: N1cho
Anyone know what does the ic svr5-04 do...
Post from page 150 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1258567/#msg1258567)
Quote from: N1cho
I have remove it. yet.. the LCD only turn on if the rotary switch is press..  lcd all white, led not on..  those below the led ,9012, 9014 ,7550. Heat up...
Check to see if you have the same problem of a bridged connection as the image shows from a member on page 133 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1149084/#msg1149084) of this thread.
(Image attached)
There have also been circumstances where the SVR05 chip was attached backwards by the supplier.
Quote from: N1cho
After the svr5-04 remove must i solder across or leave it?
Leave it.
The chip was mentioned in posts on pages 108 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1026643/#msg1026643), and 126 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1114119/#msg1114119), as well. Someone also had a blank screen from a similar AY-AT clone on page 90-91 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg988824/#msg988824).
Edited to remove pictures as mentioned in following post. (Sorry, pictures are the easiest thing for me to access quickly at the moment. I'm trying to consolidate a lot of information I've taken from here.
Note: I'm working on several subjects at once but I hope to have an AY-AT 'everything we know' guide up soon.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 31, 2017, 10:58:12 pm
jakeisprobably, that's a good answer, but I hope you never blow up any of my posts like that. Individual posts are easily linked to on this forum and do not require a huge screenshot that does not automatically collapse  and causes lots of unnecessary scrolling.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on August 03, 2017, 03:10:57 pm
Thanks for all the help guys.. thank you very much.. after removing both protection finally my dead module came alive...

Now it's time to make a good casing for it...

I decided to use a step up and  so that i can use power bank to power it up instead of putting 2 li-on battery and a charger to charge...

 Once again thanks...

Nicho

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Title: Re: $20 LCR ESR Transistor checker project
Post by: AnthLion on August 03, 2017, 07:39:19 pm
Just received a "2017 M328" LCR using the AT-AY rotary encoder from a seller on aliexpress. Seems like the PCB fabricator for this board has better quality than the one with the PCB short from the video. The silk screen is slightly different, notice a different customer ID# and space between the part names "P6KE6V8" and "104". Verified by continuity test on DMM that there is no signal between the 5V line and the SMD capacitor. Also verified there the 5V line coming into lane "1" is closed (not an open trace).
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 04, 2017, 06:48:29 pm
Just received a "2017 M328" LCR using the AT-AY....
 ...notice a different customer ID#
How do you know the "K" number is a "customer ID?" Is there any information on this or does someone know who is manufacturing this PCB?
Reversed SRV5-04 chips have been found on multiple boards with different "K" numbers. The bridged connection appears to be a bit of a fluke from 1 member IIRC. It was on a PCB with the most common number marking "K103603BS."
 I haven't seen a pattern of problems that relate to the numbers I have notes on so far:
K108783BSJH
K134443BSJH
K103603BS
K120263BSJH
K131211BSJH
 One board mentioned didn't have AY-AT printed, it was only marked 2578-AT, and a couple oddballs have the "K" number in a different location. One member here appears to have received a blank microcontroller but his final solution was not documented.
 In my opinion, the problems people have found are simply related to a lack of quality control measures by the manufacturer as it is cheaper to use the consumer/retailer for a QC department. The issues seem fairly typical of any mass produced product.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AnthLion on August 05, 2017, 05:05:08 am
How do you know the "K" number is a "customer ID?" Is there any information on this or does someone know who is manufacturing this PCB?
Sorry, none. When I was writing this up I had just gone through thinking about creating a prototype PCB through a batch PCB fabricator. I was just reading that they would put some ID number on my boards so they know which boards go with which orders. I should have just said "noticed a different ID".
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 06, 2017, 06:34:33 am
What am I missing for a complete list of displays that relate to the firmware options? See any corrections I should make? :scared:

Edit: I came across the New Haven Display website (http://www.newhavendisplay.com) with one of the best visual references that shows what screens are available that work with a specific driver. If someone wants to build their own design or whatnot this is an interesting reference. You can search by driver on their site. (No affiliation)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 06, 2017, 10:38:57 am
... also ILI9341/ILI9342, PCD8544 (Nokia 3310/5110) and ST7920.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 06, 2017, 07:47:08 pm
... also ILI9341/ILI9342, PCD8544 (Nokia 3310/5110) and ST7920.
  (ILI9341/ILI9342/ST7920) These were (last night)/are currently driving me crazy!!
I am having trouble finding where they came from/who has used them on a Transistor Tester project. I've even joined a couple of extra forums just to search through their threads. If anyone has an example or knows of a clone that uses one of these controllers that I may have overlooked please let me know. I thought someone on the badcaps forum had a ST7920 but I wasn't clear on what they had... even after reading about 10 pages.

   I think skipping them was my poor attempt at sweeping them under the lazy rug. The last Nokia option was an honest mistake.
  There are many different screens and breakout board options that support these LCD controllers. I'm hesitant to show a visual identification image that is not relevant to most people.... I probably need to separate these options by Clones vs DIY options.

BTW What happened to this:
Just soldered a display adapter board for an ILI9342 based display with touch screen :) Let's see if I'm able to add touch screen support to the firmware.
  I didn't see any follow up info after this post (because I have tunnel vision). Hopefully it's not a touchy subject??

Edit: stupid me....I should have done another search for "touch screen instead of sticking to the context of a ILI9342 search...
- Mr Wumbus
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 06, 2017, 08:56:41 pm
I think skipping them was my poor attempt at sweeping them under the lazy rug. The last Nokia option was an honest mistake. There are many different screens and breakout board options that support these LCD controllers. I'm hesitant to show a visual identification image that is not relevant to most people.... I probably need to separate these options by Clones vs DIY options.

That seems to be a good idea. Just as a side note, the next m-firmware version will support a 180° display rotation for the ST7920. All done in software since the ST7920 is a PITA and doesn't support different addressing modes like other controllers do.

BTW What happened to this:
Just soldered a display adapter board for an ILI9342 based display with touch screen :) Let's see if I'm able to add touch screen support to the firmware.
  I didn't see any follow up info after this post. Hopefully it's not a touchy subject??

A very touchy subject ;) in case you got a display with touch screen, an ADS7843 compatible touch controller, and an ATmega 324/644/1284 based tester running v1.29m. It works quite well. Any bets on how long it will take for the clone manufacturers to add touch screens?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 07, 2017, 02:09:26 am
A very touchy subject ;)

Hehe, very punny.

Quote
Any bets on how long it will take for the clone manufacturers to add touch screens?

Probably once their inventory runs low on the current versions such as the recent AY-AT variations. Maybe next year?
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on August 07, 2017, 02:37:59 am
A touch screen on such a small lcd i don't think so.... If it's bigger might be.. but  does it come handy if it's a touch screen?

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Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 07, 2017, 06:02:21 am
..does it come (in) handy if it's a touch screen?
Blackberry stock hasn't done so well...seems we all prefer scratching at a screen. The original transistor tester design is 1 button. A rotary encoder is the functional equivalent of a screen swipe left or right.
  I think it really comes down to how fast and fluid the work flow happens. The screens are probably out growing the MCU's ability to keep up.
    Personally I'd rather see development on the V2 front. In particular I think the new platform would benefit from a modular approach where the simplicity of the original is maintained on a basic design. This basic platform could be expanded as the hobbyist becomes more comfortable and wants to add additional features, but I have no idea about these things.
   
Any bets on how long it will take for the clone manufacturers to add touch screens?
I don't know, but I guarantee it will have a unique and recognizable name like TT GM328...
Get the latest GM328 "Touch Tester."
   Although the nomenclature issue is easy to remedy. We just need to name them ourselves with a little intuitive cleverness and quit using the names given by $.99 bulk sellers on the web... EZMoney... Money Booster... Old Yeller.... Big Tee... little tee... Fish... Fish 'n a Box...
my personal fav= Bat-Van
  everyone should have their own Bat-Van
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 07, 2017, 10:06:40 am
A touch screen on such a small lcd i don't think so.... If it's bigger might be.. but  does it come handy if it's a touch screen?

It really works fine with a 2.4 inch display. Instead of adding icons I've simply defined fixed areas acting as buttons. So you got left, right, top, bottom and center, while top and left got the same function at the moment (same for bottom and right). The center area is a software version of the test button. It also has a speed-up feature similar to the turning speed of a rotary encoder when you keep touching the same area. I think the next step would be voice control ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on August 07, 2017, 01:56:43 pm
I think the next step would be voice control ;D

Voice control is sooooo last year.   We want Mind Control... with the WIWIWIG (What I Want Is What I Get) interface.  I tested a scope with a WIWIWIG interface.  It didn't work quite as expected... all I got was pictures of nekid supermodels on the screen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 09, 2017, 11:43:57 pm
I have created an image index of the history of the mikrocontroller.net TT thread. I hope this is a useful reference tool for you, or at least something interesting.The video is none monotized. I am not in a position to promote or sell you anything.
https://youtu.be/ySPnq4LY3zo (https://youtu.be/ySPnq4LY3zo)

This is my 4th image index. The following are the 3 I made for the
EEVBlog Transistor Tester Thread
Part 1 of 3
https://youtu.be/on1ZrWNt2Us (https://youtu.be/on1ZrWNt2Us)
Part 2 of 3
https://youtu.be/RRJ5K752d18 (https://youtu.be/RRJ5K752d18)
Part 3 of 3
https://youtu.be/1ARlc1BHLUw (https://youtu.be/1ARlc1BHLUw)
I did not include every single picture from the mikrocontroller thread, but I did my best to represent all projects. There are 238 images in the video from pages 1-10 of the thread.
All the best, -Jake.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 10, 2017, 01:05:19 am
Thanks, Jake. It was fun "flipping" through them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: scottie4442 on August 10, 2017, 02:17:18 am
trying to build an m1284 version of this.  I have looked at Karl-Heinz schematic/pcb stuff for this but when I try to upload them to OshPark to have the boards made it says that there is no board outline file. I do not schematic software and no experience with board layout, I can assemble them and I am ok with reading a schematic. I have three of the m328 versions with the m-firmware installed and wanted some more of the options. thanks for any help on this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 10, 2017, 02:46:03 am
Thanks, Jake. It was fun "flipping" through them.
But wait there's more... The Russian forum is over 400 pages long. That's where the infamous "Nick L" resides. There's another interesting 50 pages over on the Slovak forum with Tom666. I've also tracked down several other cool references and side projects. This really changes ones perspective on things... or at least it changed mine.
   Page 8 on the mikrocontroller forum is where most of the magic happened. 1/3 of all images are from that page.
 
Some other interesting references and hybrid projects you will need an English translation app to read:
http://qsl.net/yo6pir/super.html (http://qsl.net/yo6pir/super.html)
http://www.o28.sischa.net/bauteiltester/trac/ (http://www.o28.sischa.net/bauteiltester/trac/)
http://c2.at.ua/forum/2-2-1 (http://c2.at.ua/forum/2-2-1)
http://members.upc.hu/lethanh.hung/LCFESRmero/en/index.htm (http://members.upc.hu/lethanh.hung/LCFESRmero/en/index.htm)
Most of those are pre-KH projects based around or related to Markus Frejek's original.
  I find these hybrids fascinating
... I'm way too deep in this rabbit hole  :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 10, 2017, 03:04:48 am
trying to build an m1284 version of this....
Have you tried the Nick L files?
https://drive.google.com/drive/u/0/folders/0B4yqyYy2DaakZzBVU3JDSXB6S1E
Title: Re: $20 LCR ESR Transistor checker project
Post by: scottie4442 on August 10, 2017, 03:06:48 am
Yeah these were the ones I used to try to make the board at oshpark, said the was no board outline file
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 10, 2017, 03:34:08 am
Yeah these were the ones I used to try to make the board at oshpark, said the was no board outline file
  That's above my pay grade. Sorry. I haven't seen a lot of references to oshpark. I know of 3 boards people (other than Nick L) have referenced a few times but after double checking, all are 328's. I didn't see any references to board files for the Zhqsoft versions. I haven't started to get into the main Russian thread yet. Tom has some oshpark references but nothing related to the V2 boards. Hopefully someone with experience on Oshpark can help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 10, 2017, 07:18:04 am
The Russian forum is over 400 pages long.
You have a lot of energy and time for a study of all material! It is laudable!
I will prompt one more topic from only 2 pages where I collected extract from a topic on 400 pages. If you understand Russian, it will help with a material study. :D
http://vrtp.ru/index.php?showtopic=26994 (http://vrtp.ru/index.php?showtopic=26994)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jleg on August 10, 2017, 02:01:02 pm
Yeah these were the ones I used to try to make the board at oshpark, said the was no board outline file

...this once worked for me: http://docs.oshpark.com/design-tools/gerbv/create-board-outline/ (http://docs.oshpark.com/design-tools/gerbv/create-board-outline/)
(short: the outline is in file .gbs, clone it, rename it to .gko, open in gerbv, remove all what is "in the square", and save it)

btw, on sourceforge there's a windows version of this "gerbv"... :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: dos on August 16, 2017, 01:28:30 am
I just got this tester from ebay:

(http://i.imgur.com/HyI5GT7.jpg)

It's pretty good but I really don't like how loosely the ZIF socket fits, and that it doesn't properly test zener diodes (doesn't display zener voltage) as far as I can tell, as there is no manual that I can find. Looking around I also saw this model:

(http://i.imgur.com/rDXPWtD.jpg)

This has a built in ZIF socket and does show zener voltage. They're both about the same price, is there any reason I shouldn't return mine and get this one? Has anyone had experience with both and can tell me some more about them? I really don't know anything about these other than I think one or the other or both are based on somebody's open source (?) project. Is one or the other better/more accurate? I would also like to know if there is a self test/calibration mode for the one I have, shorting pins 1, 2 and 3 did nothing.

EDIT: I also remember seeing some youtube video somewhere that said something along the lines of certain components get a more accurate analysis if they're in certain slots with these meters but I can't for the life of me remember what video it was or even if that applies to the meter I have. Has anyone heard anything like this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 16, 2017, 10:33:07 am
Both run a modified version of the open source firmware. If you're looking for the original firmware please see https://github.com/svn2github/transistortester/tree/master/Software/trunk (current k-firmware under development), https://github.com/svn2github/transistortester/tree/master/Software/Markus (m-firmware) and https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf (documentation, mainly for the k-firmware). Possibly some features are dropped in the modified firmware to make the firmware fit into the ATmegas328's flash (the fancy UI requires several kB). The accuracy of the Transistor Tester depends primarily on the Vcc regulator and the probe/test resistors (should have a tolerance of 0.1% ) . An optional 2.5V reference helps with a mediocre Vcc regulator. In case your tester got a TL431 as 2.5V reference I'd recommend to remove it or to replace it with a LM4040 or similar. PCB layout, wiring and connectors may also have an impact on the accuracy, but in general there aren't "better" probe pins for specific components. And don't forget to run the self-adjustment after a firmware upgrade.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dos on August 16, 2017, 10:55:24 am
And don't forget to run the self-adjustment after a firmware upgrade.

Thanks for the info, just wondering if you know how to run the self adjustment on this model?

E: just realized you meant after changing the firmware only, never mind. I don't really plan to mess with the firmware of this thing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: scottie4442 on August 16, 2017, 02:14:46 pm
Ok I got the files completely setup for OshPark, when I uploaded them and went through the process it finalized fine.  The price for 3 board is $77.50US, so I might have to wait a bit for this but I have the files ready to go if someone want them there are in this dropbox share, use the .zip file for OshPark,  https://www.dropbox.com/sh/clzo0mpu806kz2t/AACln2Lwuw74WSzr-O4y9aNDa?dl=0 (https://www.dropbox.com/sh/clzo0mpu806kz2t/AACln2Lwuw74WSzr-O4y9aNDa?dl=0) .

EDIT: I figured out how to list the boards with out having to order them first so they are on OshPark as "ATMega1284 transistor tester - rev_a0.02c", with credit to eevblog and Karl-Heinz. hope this helps folks out that want this version of the transistor tester.

Edit again: the price that OshPark quotes is for 3 boards, so they about $26 a piece, not sure about large quantities.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on August 16, 2017, 02:30:06 pm
Both run a modified version of the open source firmware. If you're looking for the original firmware please see https://github.com/svn2github/transistortester/tree/master/Software/trunk (current k-firmware under development), https://github.com/svn2github/transistortester/tree/master/Software/Markus (m-firmware) and https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf (documentation, mainly for the k-firmware). Possibly some features are dropped in the modified firmware to make the firmware fit into the ATmegas328's flash (the fancy UI requires several kB). The accuracy of the Transistor Tester depends primarily on the Vcc regulator and the probe/test resistors (should have a tolerance of 0.1% ) . An optional 2.5V reference helps with a mediocre Vcc regulator. In case your tester got a TL431 as 2.5V reference I'd recommend to remove it or to replace it with a LM4040 or similar. PCB layout, wiring and connectors may also have an impact on the accuracy, but in general there aren't "better" probe pins for specific components. And don't forget to run the self-adjustment after a firmware upgrade.
Hi,

Remove  the tl431.. that is to get more accurate results?

Any set back if its removed?

Sent from my E39 using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 16, 2017, 03:23:37 pm
Yep! If your tester got an external 2.5V reference it should be at least about 10 times more accurate than the Vcc regulator. If got a 6-1/2 digit or better bench DMM you could measure the external voltage reference and change the default value in the source code (Makefile or config.h). In that case a cheap voltage reference might be fine too, as long as it's stable.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 16, 2017, 09:17:09 pm
Slovak Forum thread Index:
https://youtu.be/N-CvAeKLrTs (https://youtu.be/N-CvAeKLrTs)

The Savvy Slov's have had some really interesting projects. Personally, I like the old multimeter enclosure for a transistor tester build. They also had a few really nice complete builds in custom enclosures. It's worth a look IMO.

This is the 5th Forum Thread Image Index created for this project. My goal is to compile everything I possibly can in one place that is easy for anyone to check out. The amount of information related to this project is massive. These references I have put together are just the beginning.
 Use these references to find every mention of a certain clone. Then use the page number referenced to go straight to the information your looking for. These videos are none monotized. They actually hurt my YT channel (not that I really care). This is simply a needed reference to help the community access this project easier.
Official Project Thread Index:
https://youtu.be/ySPnq4LY3zo
EEVBlog Thread Index:
https://youtu.be/on1ZrWNt2Us
https://youtu.be/RRJ5K752d18
https://youtu.be/1ARlc1BHLUw
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 17, 2017, 04:14:50 pm
I'm working on the ESR measurement (m-firmware) at the moment and like to ask you for some beta testing. For testing you would have to replace the function MeasureESR() in cap.c with following:

Code: [Select]
/*
 *  measure ESR
 *
 *  requires:
 *  - pointer to cap data structure
 *
 *  returns:
 *  - ESR in 0.01 Ohm
 *  - UINT16_MAX on any problem
 */

uint16_t MeasureESR(Capacitor_Type *Cap)
{
  uint16_t          ESR = UINT16_MAX;   /* return value */
  uint16_t          U_1;           /* voltage at probe 1 with pos. pulse unloaded */
  uint16_t          U_2;           /* voltage at probe 2 with pos. pulse loaded */
  uint16_t          U_3;           /* voltage at probe 2 with neg. pulse unloaded */
  uint16_t          U_4;           /* voltage at probe 1 with neg. pulse loaded */
  uint8_t           Probe1;        /* probe #1 */
  uint8_t           Probe2;        /* probe #2 */
  uint8_t           ADC_Mask;      /* bit mask for ADC */
  uint8_t           n;             /* counter */
  uint32_t          Sum_1;         /* sum #1 */
  uint32_t          Sum_2;         /* sum #2 */
  uint32_t          Value;

  /* check for a capacitor >= 10nF */
  if ((Cap == NULL) ||
      (CmpValue(Cap->Value, Cap->Scale, 10, -9) < 0)) return ESR;


  /*
   *  init stuff
   */

  DischargeProbes();                    /* try to discharge probes */
  if (Check.Found == COMP_ERROR) return ESR;   /* skip on error */

  UpdateProbes(Cap->A, Cap->B, 0);      /* update probes */
  Probe1 = Probes.ADC_1;                /* ADC MUX for probe-1 */
  Probe2 = Probes.ADC_2;                /* ADC MUX for probe-2 */

  Probe1 |= ADC_REF_BANDGAP;            /* select bandgap reference */
  Probe2 |= ADC_REF_BANDGAP;            /* select bandgap reference */

  /* bitmask to enable and start ADC */
  ADC_Mask = (1 << ADSC) | (1 << ADEN) | (1 << ADIF) | ADC_CLOCK_DIV;

  /* init variables */
  Sum_1 = 1;             /* 1 to prevent division by zero */
  Sum_2 = 1;             /* 1 to prevent division by zero */


  /*
   *  We have to create a delay to shift the middle of the current pulse to
   *  the ADC's S&H. S&H happens at 1.5 ADC clock cycles after starting the
   *  conversion. We synchronize to a dummy conversion done directly before,
   *  so we have 2.5 ADC clock cycles to S&H. The required delay between the
   *  dummy conversion and S&H of the next conversion is:
   *    MCU cycles for 2.5 ADC clock cycles
   *    - MCU cycles for waiting loop for completion of dummy conversion (4)
   *    - MCU cycles for starting next conversion (2)
   *    - MCU cycles for fixed pre-delay of 10µs
   *    - MCU cycles for enabling pulse (4)
   *    - MCU cycles for half-pulse (2µs)
   *
   *  MCU     ADC      MCU cycles for       
   *  clock   clock    2.5 ADC cycles  pre-delay   half-pulse  delay
   *  ---------------------------------------------------------------
   *   8 MHz  125 kHz   160 (20µs)      80 (10µs)  16 (2µs)     54
   *                                               32 (4µs)     38
   *  16 MHz  125 kHz   320 (20µs)     160 (10µs)  32 (2µs)    118
   *                                               64 (4µs)     86
   *  20 MHz  156.25    320 (16µs)     200 (10µs)  40 (2µs)     70
   *                                               80 (4µs)     30
   * 
   *  Skipping the second half-pulse allows us to measure low value caps too.
   */

  /* delay for pulse */
  /* MCU cycles for one ADC cycle * 2.5 - MCU cycles for 10µs
     - MCU cycles for half-pulse - 10 */
  U_1 = ((MCU_CYCLES_PER_ADC * 25) / 10) - (MCU_CYCLES_PER_US * 10)
        - (MCU_CYCLES_PER_US * 2) - 10;
  #if CPU_FREQ == 8000000
  /* magic time shift to compensate missing second half-pulse */
  U_1 -= 4;
  #endif
  n = (uint8_t)U_1;

  /* set up delay timer */
  if (SetUpDelayTimer(n) == 0) return ESR;   /* skip on error */


  /*
   *  measurement loop:
   *  - simulate AC by short positive and negative pulses
   *  - measure start voltage without DUT
   *  - measure pulse voltage with DUT
   *  - pre-charge DUT with a negative pulse of half length to
   *    to compensate voltage rise by positive charging pulse
   *  - 16 & 20 MHz MCUs seem to measure higher ESR values
   */ 

  ADC_PORT = 0;          /* set ADC port to low */
  ADMUX = Probe1;        /* set input channel to probe-1 & set bandgap ref */
  wait10ms();            /* time for voltage stabilization */

  U_2 = 50;              /* don't start with positive half-pulse */
  U_4 = 0;               /* start with a negative half-pulse */
  n = 255;               /* set loop counter */

  while (n > 0)
  {
    wdt_reset();                   /* reset watchdog */

    /*
     *  mitigate runaway of cap's charge/voltage
     */

    if (U_4 < 50)
    {
      /* charge cap a little bit more (negative pulse) */

      /* set probes: GND -- probe-2 / probe-1 -- Rl -- 5V */
      ADC_DDR = Probes.Pin_2;      /* pull down probe-2 directly */
      R_PORT = Probes.Rl_1;        /* pull up probe-1 via Rl */
      R_DDR = Probes.Rl_1;         /* enable pull up */
      wait2us();                   /* wait half-pulse */
      R_DDR = 0;                   /* disable any pull up */     
      R_PORT = 0;                  /* reset probe resistors */
    }

    if (U_2 < 50)
    {
      /* charge cap a little bit more (positive pulse) */

      /* set probes: GND -- probe-1 / probe-2 -- Rl -- 5V */
      ADC_DDR = Probes.Pin_1;      /* pull down probe-1 directly */
      R_PORT = Probes.Rl_2;        /* pull up probe-2 via Rl */
      R_DDR = Probes.Rl_2;         /* enable pull up */
      wait2us();                   /* wait half-pulse */
      R_DDR = 0;                   /* disable any pull up */     
      R_PORT = 0;                  /* reset probe resistors */
    }


    /*
     *  forward mode, probe-1 only (probe-2 in HiZ mode)
     *  set probes: GND -- probe-1 -- Rl -- 5V / probe-2 -- HiZ
     *  get voltage at probe-1 (voltage at RiL)
     */

    ADC_DDR = Probes.Pin_1;        /* pull down probe-1 directly to GND */
    R_PORT = Probes.Rl_1;          /* pull up probe-1 via Rl */
    R_DDR = Probes.Rl_1;           /* enable resistor */
    ADMUX = Probe1;                /* set input channel to probe-1 & set bandgap ref */
    /* run dummy conversion for ADMUX change */
    ADCSRA = ADC_Mask;             /* start conversion */
    while (ADCSRA & (1 << ADSC));  /* wait until conversion is done */
    /* real conversion */
    ADCSRA = ADC_Mask;             /* start conversion */
    while (ADCSRA & (1 << ADSC));  /* wait until conversion is done */
    U_1 = ADCW;                    /* save ADC value */


    /*
     *  forward mode, positive charging pulse
     *  set probes: GND -- probe-1 / probe-2 -- Rl -- 5V
     *  get voltage at probe-2 (voltage at DUT, i.e. RiL + ESR)
     */

    ADMUX = Probe2;                /* set input channel to probe-2 & set bandgap ref */
    /* run dummy conversion for ADMUX change */
    ADCSRA = ADC_Mask;             /* start conversion */
    while (ADCSRA & (1 << ADSC));  /* wait until conversion is done */

    /* read ADC in the mid of a positive charging pulse */
    ADCSRA = ADC_Mask;             /* start conversion with next ADC clock cycle */
    wait10us();                    /* fixed pre-delay */
    DelayTimer();                  /* delay for pulse */
    R_PORT = Probes.Rl_2;          /* pull up probe-2 via Rl */
    R_DDR = Probes.Rl_2;           /* enable resistor */
    wait2us();                     /* first half-pulse */
                                   /* S/H happens here */
    #if CPU_FREQ < 8000000
    wait2us();                     /* second half-pulse */
    #endif
    R_PORT = 0;                    /* set resistor port to low */
    R_DDR = 0;                     /* set resistor port to HiZ */
    while (ADCSRA & (1 << ADSC));  /* wait until conversion is done */
    U_2 = ADCW;                    /* save ADC value */


    /*
     *  reverse mode, probe-2 only (probe-1 in HiZ mode)
     *  set probes: GND -- probe-2 -- Rl -- 5V / probe-1 -- HiZ
     *  get voltage at probe 2 (voltage at RiL)
     */

    ADC_DDR = Probes.Pin_2;        /* pull down probe-2 directly */
    R_PORT = Probes.Rl_2;          /* pull up probe-2 via Rl */
    R_DDR = Probes.Rl_2;           /* enable resistor */
    ADMUX = Probe2;                /* set input channel to probe-2 & set bandgap ref */
    /* run dummy conversion for ADMUX change */
    ADCSRA = ADC_Mask;             /* start conversion */
    while (ADCSRA & (1 << ADSC));  /* wait until conversion is done */
    /* real conversion */
    ADCSRA = ADC_Mask;             /* start conversion */
    while (ADCSRA & (1 << ADSC));  /* wait until conversion is done */
    U_3 = ADCW;                    /* save ADC value */


    /*
     *  reverse mode, negative charging pulse
     *  set probes: GND -- probe-2 / probe-1 -- Rl -- 5V
     *  get voltage at probe-1 (voltage at DUT, i.e. RiL + ESR)
     */

    ADMUX = Probe1;                /* set input channel to probe-1 & set bandgap ref */
    /* run dummy conversion for ADMUX change */
    ADCSRA = ADC_Mask;             /* start conversion */
    while (ADCSRA & (1 << ADSC));  /* wait until conversion is done */

    /* read ADC in the mid of a negatve charging pulse */
    ADCSRA = ADC_Mask;             /* start conversion with next ADC clock cycle */
    wait10us();                    /* fixed pre-delay */
    DelayTimer();                  /* delay for pulse */
    R_PORT = Probes.Rl_1;          /* pull up probe-1 via Rl */
    R_DDR = Probes.Rl_1;           /* enable resistor */
    wait2us();                     /* first half-pulse */
                                   /* S/H happens here */
    #if CPU_FREQ < 8000000
    wait2us();                     /* second half-pulse */
    #endif
    R_PORT = 0;                    /* set resistor port to low */
    R_DDR = 0;                     /* set resistor port to HiZ */
    while (ADCSRA & (1 << ADSC));  /* wait until conversion is done */
    U_4 = ADCW;                    /* save ADC value */


    /*
     *  manage measured values
     */

    Sum_1 += U_1;        /* positive pulse without DUT */
    Sum_1 += U_3;        /* negative pulse without DUT */
    Sum_2 += U_2;        /* positive pulse with DUT */
    Sum_2 += U_4;        /* negative pulse with DUT */
    n--;                 /* next loop run */
  }


  /*
   *  process measurements
   */

  if (Sum_2 > Sum_1)               /* valid measurement */
  {
    /*
     *  calculate ESR
     *  - ESR = U_ESR / I_ESR
     *    with U_ESR = (U2 or U4) and I_ESR = (U1 or U3) / RiL
     *    ESR = (U2 or U4) * RiL / (U1 or U3)
     *  - since we divide (U2 or U4) by (U1 or U3), we don't need to convert
     *    the ADC value into a voltage and simply desample the sums.
     *  - so ESR = Sum_2 * RiL / Sum_1
     *  - for a resolution of 0.01 Ohms we have to scale RiL to 0.01 Ohms
     */

    /* voltage across the DUT (raw value) */
    Sum_2 -= Sum_1;           /* subtract voltage at DUT's low side (RiL) */

    /* ESR = Sum_2 * RiL / Sum_1 */
    Value = (uint32_t)(NV.RiL * 10);    /* RiL in 0.01 Ohms */
    Value *= Sum_2;                     /* sum of raw values for voltage across DUT */
    Value /= Sum_1;                     /* sum of raw values for voltage at RiL */
    U_1 = (uint16_t)Value;

    /* consider probe resistance */
    if (U_1 > NV.RZero)            /* larger than offset */
    {
      U_1 -= NV.RZero;             /* subtract offset */
      ESR = U_1;                   /* got result */
    }
    else                           /* offset problem or zero */
    {
      /* should only happen for large caps */
      if (CmpValue(Cap->Value, Cap->Scale, 1000, -6) > 0)
      {
        ESR = 0;                   /* can't be less than 0 Ohms */
      }
    }
  }

  /* update Uref flag for next ADC run */
  Cfg.RefFlag = ADC_REF_BANDGAP;   /* update flag */

  return ESR;
}

Because the "non valid" return value has changed, you also need to modify Show_Capacitor() in main.c and ESR_Tool() in extras.c. Simply change

Code: [Select]
if (ESR > 0)

into

Code: [Select]
if (ESR < UINT16_MAX)

That should support caps down to 10nF. The ESR values may differ a few percent for different MCU clocks because of the different test frequencies (-> Fourier series). Please let me know if the changes work for you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 17, 2017, 07:02:16 pm
Sorry I'm unable to help on the ESR experiment request ATM (still haven't finished my little tester).

 However, out of curiosity I have been wondering about a few questions. Hopefully someone can clear this up for me.

1.) What are the repercussions if someone were to build a transistor tester with different values for the probing resistors? For example, what if someone parallels 2 precision 1M resistors to make 500k's instead of a 470k, and/or parallels 2 1k's to make a 500ohm instead of a 680? Is this possible?

2.) Is the temperature coefficient of the resistors important in this application? What is the difference between someone measuring their stock of 5% resistors until they find 3 within 0.1% as opposed to purchasing 0.1% resistors outright?

3.) What about variations between the resistors on each channel? Is it more important to have resistors that are matched equally between each of the three probing channels or is it more important for the software to have the precision value of each resistor?

Thanks in advance, -Jake.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 17, 2017, 08:31:25 pm
1.) What are the repercussions if someone were to build a transistor tester with different values for the probing resistors? For example, what if someone parallels 2 precision 1M resistors to make 500k's instead of a 470k, and/or parallels 2 1k's to make a 500ohm instead of a 680? Is this possible?

Basically that's possible, but it will impact the resolution of some measurements and might render some measurement methods useless. If the values don't differ hugely from the defaults, like in your example, it should be ok.

2.) Is the temperature coefficient of the resistors important in this application? What is the difference between someone measuring their stock of 5% resistors until they find 3 within 0.1% as opposed to purchasing 0.1% resistors outright?

The Transistor Tester is no precision instrument, therefore the temperature coefficient isn't that important. Selecting the resistors is fine if you got a proper DMM. Resistors with a 0.1% tolerance are much less expensive than a 6-1/2 digit bench DMM ;)

3.) What about variations between the resistors on each channel? Is it more important to have resistors that are matched equally between each of the three probing channels or is it more important for the software to have the precision value of each resistor?

The resistors should be matched across all three channels. The firmware is designed that way to keep the math simple and the firmware small.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 18, 2017, 06:55:15 am
Madires, you could prepare the new files cap.c and main.c ,extras.c  with for changeover of original?
I am ready to participate in testing!
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 18, 2017, 05:32:10 pm
Ya know... I try to wait until I'm done with a thread before sharing what I found, but in the first 10 pages of the Russian TT thread I found my hero:
(https://lh3.googleusercontent.com/-KWdxJ69Yc0Y/WZchyI_fvdI/AAAAAAAAAa0/wRj5ivP5NHwDZSi7tiQdbHparQrFq5ZMwCHMYCw/s1600/Rp9h.jpg)
I love upcycled junk...( I'm such a cheap hobo bastard...lol)

...I think I saved the best thread archive for last.
  The attached images are real creative catalysts for me. I have been mulling over the idea of how to integrate a mechanical clamping mechanism for a few weeks. The second I saw this it advanced my creative process exponentially
Russian genius! ;)
Edit:
https://youtu.be/1mUm0phFMJA (https://youtu.be/1mUm0phFMJA)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 18, 2017, 05:58:20 pm
Madires, you could prepare the new files cap.c and main.c ,extras.c  with for changeover of original?
I am ready to participate in testing!

Happy testing ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tablatronix on August 19, 2017, 03:06:23 am
Just put together one of the 2017 2578ay-at versions. I apologize for not reading the full thread, all 255 pages of it. But is anyone working on a branch with full color support and a snappier UI? Just seems like a waste with this restricted boring ui, is this really pushing at 328 as is. looks like its using 1.12k from seller.

Impressive spftware nonetheless, and hardware is killer for under $10

Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on August 19, 2017, 07:38:55 am
I'm working on the ESR measurement (m-firmware) at the moment and like to ask you for some beta testing. For testing you would have to replace the function MeasureESR() in cap.c with following:
...
...

I have the MK328 variant, with 126x64 lcd (fpc-12864). Is you code compatible?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 19, 2017, 09:39:57 am
Just put together one of the 2017 2578ay-at versions. I apologize for not reading the full thread, all 255 pages of it. But is anyone working on a branch with full color support and a snappier UI? Just seems like a waste with this restricted boring ui, is this really pushing at 328 as is. looks like its using 1.12k from seller.

You'll be eligible for an answer after reading all 255 pages and passing the Transistor Tester Advanced Technician exam. Just kidding. :) A fancy UI with full color support would incease the firmware size dramatically. So you'd have to drop several measurements and extras to make the firmware still fit into the ATmega 328`s 32kB flash memory. The m-firmware provides a little bit more colorful UI than the k-firmware, while the k-firmware has a menu function to change the fore/background colors. You can change the colors in the m-firmware too (colors.h). And if you want a really fancy tester build your own based on the 644/1284 circuit and add a touch screen. 8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 19, 2017, 10:04:18 am
I have the MK328 variant, with 126x64 lcd (fpc-12864). Is you code compatible?

Presumably, if the MK328 got a LCD controller supported by the m-firmware.

BTW, if someone runs the m-firmware on a tester not listed in the "Clones" file, please send me your settings. I'll add them to the list to help other users.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tablatronix on August 19, 2017, 03:33:59 pm
I have the MK328 variant, with 126x64 lcd (fpc-12864). Is you code compatible?

Presumably, if the MK328 got a LCD controller supported by the m-firmware.

BTW, if someone runs the m-firmware on a tester not listed in the "Clones" file, please send me your settings. I'll wil add them to the list to help other users.

Thanks I figured as much, Ill check out the M fw. I am going to assume these cheap color lcds have no buffer hence the full screen slow updating during menu operations.

What variant is this chinese clone considered, came with no smd soldered ( and missing a resistor, arghh ), ignore my isp mod.

I am gonna have to update is soon, it wont save calibration, or always complains for some reason, and wont let me set the foreground to white, I think there is a bug in this version of fw, green channel goes to 63, rb goes to 31. shrug.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MickM on August 19, 2017, 09:19:57 pm
Hi;
  You seem to be missing 3 of the input resistors.
So you only have 1 1/2 channels, not 3.

Mick M.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 20, 2017, 09:39:07 am
Thanks I figured as much, Ill check out the M fw. I am going to assume these cheap color lcds have no buffer hence the full screen slow updating during menu operations.

Color displays are slower because the Transistor Tester has to send 16 bits for a pixel instead of 1 bit for a monochrome display. And bit-banging SPI also adds some delay. You could upgrade your tester with a 16 MHz crystal to speed up the display output. With an ATmega 324/644/1284 it's possible to run hardware SPI.

PS: Your clone seems to be the AY-AT kit..
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 20, 2017, 09:48:00 am
  You seem to be missing 3 of the input resistors.
So you only have 1 1/2 channels, not 3.

Maybe his clone was 50% off at AliExpress >:D BTW, I'd go for resistors with a 0.1% tolerance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tablatronix on August 20, 2017, 03:08:01 pm
I was only missing one resistor 3k3, the sellers pdf bom said 1 when there are 2 needed, so I had to stick a carbon in there for now.

So this appears to be ay-at ST7735 color 2017 version.

I read through https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf) so I am understanding this a bit better now.

Finally got the config to save, it kept saying cap  > 100nf but I had to put a much larger cap in to get it to acknowledge for some reason.

Is there somewhere that describes the calibration proceedure and what the calibration values mean?

Yeah the resistors are shit, gotta be careful buying these cheaper chinese kits
Title: Re: $20 LCR ESR Transistor checker project
Post by: tablatronix on August 20, 2017, 05:19:47 pm
ah the rgb bitdepth is not a bug, makefile shows 6 bit G, that is how 16bit works on the ST7735

Quote
-16-bit/pixel: RGB=(565) using the 384k-bit frame
memory and LUT

It also supports 12bit..
Title: Re: $20 LCR ESR Transistor checker project
Post by: tablatronix on August 20, 2017, 06:20:02 pm
hmm anybody build this with osx toolchain ?

Quote
avr-gcc -mmcu=atmega328p -Wl,--relax,-Map=TransistorTester.map lcd_hw_4_bit.o lcd-routines.o i2lcd.o PinLayout.o RvalOut.o UfAusgabe.o DisplayValue.o lcd-draw.o swuart.o wait1000ms.o  sleep_5ms.o ReadADC.o wait_for_key_ms.o RefVoltage.o get_log.o main.o Battery_check.o CheckPins.o GetResistance.o ChargePin10ms.o EntladePins.o ReadCapacity.o GetRLmultip.o Calibrate_UR.o show_Resis_Cap.o ReadInductance.o GetESR.o GetVloss.o GetFrequency.o function_menu.o message_key_released.o ReadBigCap.o CheckRotaryEncoder.o CalibrationCap.o ShowData.o CheckUJT.o EE_check_init.o samplingADC.o sampling_cap.o sampling_lc.o sampling_xtal.o    -o TransistorTester.elf
/usr/local/opt/avr-binutils/bin/avr-ld: BFD (GNU Binutils) 2.28 assertion fail ../../bfd/elf32-avr.c:2145
collect2: error: ld returned 1 exit status
make: *** [TransistorTester.elf] Error 1

Trying to make trunk/ST7735 any idea what the problem is ? I am super newb.
osx using brew

EDIT, looks like there was a bug that might be patched in binutils 2.28.1
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on August 20, 2017, 09:11:17 pm
That's a really nice way to put the ISP connector tablatronix!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 20, 2017, 09:55:31 pm
ah the rgb bitdepth is not a bug, makefile shows 6 bit G, that is how 16bit works on the ST7735

Quote
-16-bit/pixel: RGB=(565) using the 384k-bit frame
memory and LUT

It also supports 12bit..

You could bit-bang 12 bits with the ATmega, but the hardware SPI supports only bytes. It's a tradeoff between 4 bits less and compatibility  with the hardware SPI (which is significantly faster). I don't know if there are any visible display speed differences between k and m-firmware. The m-firmware uses a simple method to keep track of text lines for color displays to skip empty lines when clearing the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 21, 2017, 01:04:48 pm
Madires, you could prepare the new files cap.c and main.c ,extras.c  with for changeover of original?
I am ready to participate in testing!

Happy testing ;)
Hi, madires! :)
I made the ESR tests on 4 capacitors:
 1. 10nFx630V
 2. 27.75nFx250V
 3. 220nFx250V
 4. 560nFx250V
Resonator  quartz 20MHz!
For comparing I made measurements of DE-5000 at frequencies 1kHz, 10kHz, 100kHz and also on a tester with a firmware from Karl-Heinz (1.13k rev.705).
Apparently, results strongly differ and strongly depend on measurement frequency. For not electrolytic capacitors it is difficult to make the correct measurement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RadoK on August 21, 2017, 01:30:21 pm
Hi,
I am planning to build the tester. It is probably cheaper to buy a kit but I think I have "do it yourself deficiency" :-)

Two questions about hardware implementation.
1) Why so complicated power supply part with three transistors? Isn't a regulator with shutdown pin sufficient?
2) I haven't checked firmware sources files yet to see if SW is doing rotary encoder debounce. I wonder if debounce capacitors can help here.

Regards,
Rado
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on August 21, 2017, 02:39:39 pm

I am planning to build the tester. It is probably cheaper to buy a kit but I think I have "do it yourself deficiency" :-)


Save yourself a lot of work and potential grief.  Buy an assembled unit... they only cost a few dollars more than a kit.  Kit instructions are notoriously bad or non-existent.   They really aren't for noobs.   Way too many people have problems with them.   I'd look for an AY-AT version with a socketed DIP processor chip.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on August 21, 2017, 04:51:21 pm
Most of the questions are explained a lot of times in this topic 😉
And not to forget in the extensive manual in the repository.
For the ay-at version there are reasonable build instructions...

Some people seem not to have energy to do a good search and read 😁
I thought that this device was for people who have at least some
experience with electronics why should they otherwise need such?
Title: Re: $20 LCR ESR Transistor checker project
Post by: RadoK on August 21, 2017, 09:37:05 pm
Save yourself a lot of work and potential grief.  Buy an assembled unit...

My goal is not to have it. I would like to build something after few months break (abstinence syndrom :-)). This transistor tester projects seem to be nice one.
So goal is to have my "hands dirty" and to say "I did it!" at the end. Older hobbyist will understand :-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on August 21, 2017, 09:43:35 pm
Save yourself a lot of work and potential grief.  Buy an assembled unit...

My goal is not to have it. I would like to build something after few months break (abstinence syndrom :-)). This transistor tester projects seem to be nice one.
So goal is to have my "hands dirty" and to say "I did it!" at the end. Older hobbyist will understand :-)

I've only been doing this for over 50 years...  really older hobbyists knows where the dragons lie, how they like to bite your ass,  and how best to avoid them.  There are much more fruitful and rewarding ways to get your hands dirty than building some poorly, if at all, documented Chinese kit.  But go for it if it makes you happy!
Title: Re: $20 LCR ESR Transistor checker project
Post by: RadoK on August 21, 2017, 10:17:25 pm
No texaspyro :-) I am for sure not going to buy any kit. I am going to build it from scratch. Starting with schematics, PCB design, PCB making, etching, applying mask, soldering. To make it more painful I am going to avoid through-hole as much as possible and to use all the 0603 parts I have collected.
Only this will satisfy my need to build something again in near future :-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 21, 2017, 10:21:21 pm
I just released part 1 of the Russian thread image reference. These guys did some awesome stuff. It predates Karl-Heinz and Markus R. There are several PIC microcontroller based designs. There is also a reference link to a site talking about porting the project to a STM8 MCU. I didn't chase that rabbit down the hole to see where it leads. I just noticed the ref.
  In the video I noted the years and when KH started the official Project Thread on mikrocontroller.net. Hopefully this gives everyone a better idea of where the project was at at the time. This new video is basically none stop DIY creativity. There were not many clones around at the time. These guys built TT projects into an answering machine, a fax machine, a home thermostat, and laptop/printer power supply enclosures. The creativity level is outstanding.
https://youtu.be/g5aDcutWiho (https://youtu.be/g5aDcutWiho)
The following post contains the image indexes for  pages1-150 of this thread, a video for pages 1-10 of the official Project Thread on mikrocontroller.net, and one for the Slovak Thread.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1277289/#msg1277289 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1277289/#msg1277289)
If your too lazy to read all the threads (yeah that's right thread"S," this one is small) these references show the page numbers of all images from the different forums, use this reference to find information about what your looking for. People have posted pictures about programming, and about every clone. Also, all the DIY projects are here for the more intellectual/creative personality types.
    At a minimum you should watch the video 'EEVBlog 3 of 3' for a summary of pages 101-150 of this thread. That will help you find the page numbers of the last 10 people that asked the same question as you.... (I'm no exception.. I'm one of those repeats too.)
  The videos are not monotized. I don't gain anything if you watch them. If you view them on YT directly, they are setup in max resolution of 1080p@60fps, although I'm limited by the quality of images others uploaded.
 Soon I hope to consolidate this information even further.
Edit:  If your going to do a DIY project the Germans and Russians have been working hard on the V2 rocketship. That platform is very versatile. There are no V2 clones available, as far as I can tell, not even on taobao. I can't search it well due to language but that hasn't stopped me from trying. There are DIY examples of V2 on the mikrocontroller.net thread, see index video/pages 8 & 9.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 21, 2017, 10:40:23 pm
Hi, madires! :)
I made the ESR tests on 4 capacitors:
 1. 10nFx630V
 2. 27.75nFx250V
 3. 220nFx250V
 4. 560nFx250V
Resonator  quartz 20MHz!
For comparing I made measurements of DE-5000 at frequencies 1kHz, 10kHz, 100kHz and also on a tester with a firmware from Karl-Heinz (1.13k rev.705).
Apparently, results strongly differ and strongly depend on measurement frequency. For not electrolytic capacitors it is difficult to make the correct measurement.

indman, for the DE-5000 measurements, am I reading the images correctly? It appears to be in Ohms mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RadoK on August 21, 2017, 11:03:11 pm
Most of the questions are explained a lot of times in this topic
And not to forget in the extensive manual in the repository.
For the ay-at version there are reasonable build instructions...

Some people seem not to have energy to do a good search and read
I thought that this device was for people who have at least some
experience with electronics why should they otherwise need such?
Judging too quickly  :P
I read the main pdf in the beginning. Then it took few weeks to go through whole thread. Today is the day I made it to the last post  :-+
It is not easy to find answers during reading or from a search in such a long thread.
Regarding my questions:
I have already used LDO with shutdown pin in a project and it allowed me to use button to power-up system and atmega pin to turn it off when needed. I am trying to find out if the power circuit in the original schematics is doing something more or I can do it my way. I have to check firmware to be sure I think.
Trying to de-bounce rotary encoder from SW can be painful (own experience from two projects). I see now that firmware has logic to track encoder states to eliminate bouncing issue. Maybe it would save few bytes of flash with HW debounce but it is probably not worth to change it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 22, 2017, 04:03:39 am
I am trying to find out if the power circuit in the original schematics is doing something more or I can do it my way.
Many people have done their own power circuit designs. Most notable are the designs by Tom666. He documents it well on his post from page 43 here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg707702/#msg707702). These are all options in the makefile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 22, 2017, 05:54:39 am
indman, for the DE-5000 measurements, am I reading the images correctly? It appears to be in Ohms mode.
Yes, it is correct! This measurement of the pure serial resistance on an AC current - Rs! I was interested only measurement of ESR on DE-5000. In the Rs=ESR mode
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 22, 2017, 10:28:03 pm
 If you get an AY-AT Clone, the following is a list of hardware corrections to order if you would like to optimize it's operation on M-Firmware. If you normally order parts from Mouser or Digikey all information and links are provided. (No Supplier Affiliation/No Financial Affiliate Program Links) This is simply a resource to make the information easier for the next person to find.
AY-AT Clone - The Proper Mods
1.) 0.1% Probing Resistors
2.) 20mhz Crystal
3.) Correct LDO Vreg
4.) Correct Vref

Manufacturers Part Number=MPN
Mouser Part Number=MoPN
Digikey Part Number=DkPN

(3×)470k Resistors
TE Connectivity
MPN: H8470KBZA
Metal Film Resistors - Through Hole H8 470K 0.1% 100PPM
MoPN: 279-H8470KBZA (http://www.mouser.com/Search/ProductDetail.aspx?R=H8470KBZAvirtualkey50680000virtualkey279-H8470KBZA)
$0.97each (8/2017)
$2.91 (×3)
DkPN: PTF475KCCT-ND (https://www.digikey.com/product-detail/en/te-connectivity-passive-product/H8470KBZA/H8470KBZA-ND/2373532) (not stocked)
Dk Alt:
475k 0.1% 1/8W
Vishay Dale
MPN: PTF56475K00BYEB
DkPN: PTF475KCCT-ND (https://www.digikey.com/product-detail/en/vishay-dale/PTF56475K00BYEB/PTF475KCCT-ND/2273757)
$1.64each (8/2017)

(3×)680ohm Resistors
TE Connectivity
MPN: H8680RBYA
Metal Film Resistors - Through Hole H8 680R 0.1% 15PPM
MoPN: 279-H8680RBYA (http://www.mouser.com/Search/ProductDetail.aspx?R=H8680RBYAvirtualkey50680000virtualkey279-H8680RBYA)
$1.14each (8/2017)
$3.42 (×3)
DkPN: H8680RBYA-ND (https://www.digikey.com/product-detail/en/te-connectivity-passive-product/H8680RBYA/H8680RBYA-ND/2373526)(not stocked)
Dk Alt:
681ohm 0.1% 1/4W
Note: listed as discontinued by digikey (w/available stock 8/2017)
TT Electronics/Welwyn
MPN: RC55Y-681RBI
DkPN: 985-1036-1-ND (https://www.digikey.com/product-detail/en/tt-electronics-welwyn/RC55Y-681RBI/985-1036-1-ND/2401900)
$1.70each (8/2017)

20mhz Crystal
CTS
MPN: ATS20A
Crystals 20MHz 20pF 30ppm -20C 70C
MoPN: 774-ATS20A (http://www.mouser.com/Search/ProductDetail.aspx?R=ATS20Avirtualkey67110000virtualkey774-ATS20A)
$0.36 (8/2017)
DkPN: CTX1106-ND (https://www.digikey.com/product-detail/en/cts-frequency-controls/ATS20A/CTX1106-ND/2640038)
$0.36 (8/2017)

Spare ATmega328
Microchip
MPN: ATMEGA328-PU
8-bit Microcontrollers - MCU AVR 32K FLSH 1K EE2K SRAM-20MHz IND
MoPN: 556-ATMEGA328-PU (http://www.mouser.com/Search/ProductDetail.aspx?R=ATMEGA328-PUvirtualkey55660000virtualkey556-ATMEGA328-PU)
$1.95each (8/2017)
DkPN: ATMEGA328-PU-ND (https://www.digikey.com/products/en?keywords=ATMEGA328-PU)
$1.96each (8/2017)

2.5 Volt 0.1% Precision Reference
Texas Instruments
MPN: LM4040AIZ-2.5/NOPB
Voltage References Prec MicroPwr Shunt Vtg Ref
MoPN: 926-LM4040AIZ25NOPB (http://www.mouser.com/Search/ProductDetail.aspx?R=LM4040AIZ-2.5%2fNOPBvirtualkey59500000virtualkey926-LM4040AIZ25NOPB)
$1.72 (8/2017)
DkPN: LM4040AIZ-2.5/NOPB-ND (https://www.digikey.com/products/en?keywords=LM4040AIZ-2.5%2FNOPB)
$1.73 (8/2017)

5v LDO Voltage Regulator
Microchip
MPN: MCP1702-5002E/TO
LDO Voltage Regulators LDO w/ Low Quiescent
MoPN: 579-MCP1702-5002E/TO (http://www.mouser.com/Search/ProductDetail.aspx?R=MCP1702-5002E%2fTOvirtualkey57940000virtualkey579-MCP1702-5002E%2fTO)
$0.52each (8/2017)
DkPN: MCP1702-5002E/TO-ND (https://www.digikey.com/products/en?keywords=MCP1702-5002E%2FTO)
$0.49each (8/2017)

Total
Mouser: $10.88 (8/2017)
(+USA Econ Shipping@$4.99)
Digikey: $14.56 (8/2017)
(+ Shipping I'm too lazy to look this up)

Mouser USA Part Links Consolidated:
470k Resistors (http://www.mouser.com/Search/ProductDetail.aspx?R=H8470KBZAvirtualkey50680000virtualkey279-H8470KBZA)
680ohm Resistors (http://www.mouser.com/Search/ProductDetail.aspx?R=H8680RBYAvirtualkey50680000virtualkey279-H8680RBYA)
20mhz Crystal (http://www.mouser.com/Search/ProductDetail.aspx?R=ATS20Avirtualkey67110000virtualkey774-ATS20A)
ATmega328 (http://www.mouser.com/Search/ProductDetail.aspx?R=ATMEGA328-PUvirtualkey55660000virtualkey556-ATMEGA328-PU)
LM4040 Vref (http://www.mouser.com/Search/ProductDetail.aspx?R=LM4040AIZ-2.5%2fNOPBvirtualkey59500000virtualkey926-LM4040AIZ25NOPB)
MCP1702 LDO Vreg (http://www.mouser.com/Search/ProductDetail.aspx?R=MCP1702-5002E%2fTOvirtualkey57940000virtualkey579-MCP1702-5002E%2fTO)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tablatronix on August 23, 2017, 01:27:11 am
Great list i was just looking into this, i thought 16mhz was the limit. What about the trimmer cap to calibrate crystal for freq meter function, I saw that mentioned in the pdf, but no other details.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 23, 2017, 02:20:02 am
... I thought 16mhz was the limit.
K Firmware = 8 or 16mhz
M Firmware = 8, 16, or 20mhz
... What about the trimmer cap to calibrate crystal for freq meter function, I saw that mentioned in the pdf, but no other details.
The trimmer capacitor is certainly an option, and I plan to look into it myself, but I do not have a metrology grade frequency measurement device, so I'd hate to ask someone to follow me over a cliff ;)
 As I understand it you only need a trimmer cap that can adjust from 0-~20pF. You can literally open up almost any old junk radio up until the early 2000's and find one.
 At worst, I hope to build one of the GPS frequency standards from Scullcom Hobby Electronics YouTube channel one of these days. Then I'll have a more precise frequency measurement potential... I think...  :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on August 23, 2017, 02:48:14 am

 At worst, I hope to build one of the GPS frequency standards from Scullcom Hobby Electronics YouTube channel one of these days. Then I'll have a more precise frequency measurement potential... I think...  :scared:


Don't bother...  they guy's design is based upon a fundamental misunderstanding of how those modules work.  The oscillator is NOT locked to GPS.  It is just a free-running XO or TCXO.  You can program a divider in the module to generate a frequency,  but that frequency is NOT locked to anything.   It will drift and wander just like any non-disciplined oscillator... except it needlessly requires a GPS antenna.

Title: Re: $20 LCR ESR Transistor checker project
Post by: jleg on August 24, 2017, 09:41:55 am
Don't bother...  they guy's design is based upon a fundamental misunderstanding of how those modules work.  The oscillator is NOT locked to GPS.  It is just a free-running XO or TCXO.  You can program a divider in the module to generate a frequency,  but that frequency is NOT locked to anything.   It will drift and wander just like any non-disciplined oscillator... except it needlessly requires a GPS antenna.

oh, bummer; do you have a source for that? At least the data sheet for the Neo-7s says:

"The  TIMEPULSE  output generates pulse  trains  synchronized  with  GNSS  or  UTC  time  grid  with  intervals  configurable over a wide frequency range. Thus it may be used as a low requency time synchronization pulse or as a high frequency reference signal. "

And the Neo-7 protocol description clearly states the parameters for TIMEPULSE feature named "lock to gps freq", "adapt to GPS antenna delay" etc.
(https://www.u-blox.com/sites/default/files/products/documents/u-blox7-V14_ReceiverDescrProtSpec_%28GPS.G7-SW-12001%29_Public.pdf (https://www.u-blox.com/sites/default/files/products/documents/u-blox7-V14_ReceiverDescrProtSpec_%28GPS.G7-SW-12001%29_Public.pdf))

So i'd guess this thing *does* lock timepulse output to GPS (or better "GNSS")?
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on August 24, 2017, 12:48:29 pm
That only means the Ublox 1PPS signal is based upon the GPS 1 Hz navigation messages.  It is accurate to within one half of the period of the on board oscillator (the difference between the 1PPS output and a true 1PPS frequency is known as the sawtooth error).

The programmable frequency outputs of the Ublox are all derived from the Ublox oscillator which is free running.  Unless the divisor is an even multiple of the Ublox oscillator they have quite a bit of jitter.

If the Ublox oscillator was locked to GPS,  everybody would be using them as GPSDO's instead of paying $100-$1000 for a real GPSDO.   Ask any time-nut...
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on August 24, 2017, 07:46:44 pm
I am trying to upgrade my Tester. I have go through most of the posts. I think it is a GM328 without a rotarty encoder and had 1.11k firmware.
Here is a picture of it post #3141 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1114370/#msg1114370)

I followed the instructions of post #2475 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926)
Downloaded 1.29m from github (https://github.com/svn2github/transistortester/tree/master/Software/Markus)
Added the ISP similar to post #2574 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1021401/#msg1021401)
Added the rotarty encoder and the resistors (MCU pins 4&5, +5v), as well as jumpering the display's CS0 to the /CS line on the interboard connector
Code: [Select]
Display   interboard Conn
1   CS0 --7 NC [jumper to 11 LCD_CS]
2   RST --6 LCD_RESET
3   CD  --3 LCD_SI ENCODER_B
4   NC
5   SCK --4 LCD_SCL ENCODER_A
6   SDA --5 LCD_A0
7   VDD   (3.3V)
8   GND --16 GND
9   VS0+ 
10  VS0-
11  VS1-
12  VS1+
13  VLCD 
14  NC

interboard Conn
1   led
2   led
3   PD3[5] LCD_SI ENCODER_A
4   PD2[4] LCD_SCL ENCODER_B
5   PD1[3] LCD_A0
6   PD0[2] LCD_RESET
7   NC
8   NC
9   NC
10  NC
11  PD5[11] LCD_CS
12  NC
13  PD4[6] TP_REF
14  NC (OLD CONTRAST POT)
15  5V
16  GND

The tester still works with the old chip.

Put in a new chip and flashed it with
Code: [Select]
avrdude -c avrisp -p m328p -P COM11 -b 19200 -e -U flash:w:"ComponentTester.hex":i -U eeprom:w:"ComponentTester.eep":i -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0x04:m
My settings -
Code: [Select]

#  MakefileMCU = atmega328

REQ = 8
OSCILLATOR = Crystal
PARTNO = m328p
PROGRAMMER = avrispmkII
PORT = usb

 *   global configuration, setup and settings
 
#define ENCODER
#define ENCODER_PULSES   4
#define ENCODER_STEPS    20
//#define HW_INCDEC_KEYS
//#define HW_REF25
#define UREF_25           2495
//#define HW_DISCHARGE_RELAY
//#define HW_ZENER
//#define HW_FREQ_COUNTER
//#define HW_IR_RECEIVER
/#define HW_ADJUST_CAP
//#define HW_CAP_RELAY
#define SW_PWM_SIMPLE
//#define SW_PWM_PLUS
#define SW_INDUCTOR
#define SW_ESR
#define SW_ENCODER
define SW_SQUAREWAVE
//#define SW_IR_RECEIVER
/#define SW_IR_DISABLE_RESISTOR
#define SW_OPTO_COUPLER
#define SW_UJT
//#define SW_PROBE_COLORS
#define SW_SERVO
#define CYCLE_DELAY      12000
#define CYCLE_MAX        1
#define BAT_R1          10000
#define BAT_R2          3300
define BAT_OFFSET       1000



*   ATmega 328 specific global configuration, setup and settings
*  ST7565R, SPI interface (bit-bang)

#define LCD_ST7565R
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD0            /* port pin used for /RES (optional) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
// PD5 is not optional if totary is used
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
//#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y                      /* enable vertical flip */
//#define LCD_OFFSET_X                    /* enable x offset of 4 dots */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     15             /* default contrast (0-63) */
#define FONT_6X8_VF                     /* 6x8 font, vertically aligned & flipped */
#define SYMBOLS_24X24_VFP               /* 24x24 symbols, vertically aligned & flipped */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SI         /* port pin used for MOSI */

#define TP1              PC0       /pin 23 * test pin 1 */
#define TP2              PC1       /pin 24 * test pin 2 */
#define TP3              PC2       /pin 25 * test pin 3 */
#define TP_REF           PC4       /pin 27 * test pin with 2.5V reference and relay */
#define TP_BAT           PC5       /pin 28 * test pin with 4:1 voltage divider */
#define POWER_CTRL       PD6       /pin 12 * controls power (1: on / 0: off) */
#define TEST_BUTTON      PD7       /pin 13 * test/start push button (low active) */
#define ENCODER_A        PD2       /pin 4 * rotary encoder A signal */
#define ENCODER_B        PD3       /pin 5 * rotary encoder B signal */

The problems I am having are
the tester cycles even though I set it to 1.
It recognizes the part (N-ch enh.) but the last line (Vf 596mV) has a bar start at the end of the mV then writes over the Vf.
When I click to get to the menu, the screen goes blank. When moving the encoder the screen flashes and has a gradient.

One last thing, I missed where the xtal tester is. I would like to add that. A xtal upgrade comes when I can get it to work at 8Mhz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 24, 2017, 08:46:33 pm
Added the rotarty encoder and the resistors (MCU pins 4&5, +5v), as well as jumpering the display's CS0 to the /CS line on the interboard connector
Code: [Select]
Display   interboard Conn
3   CD  --3 LCD_SI ENCODER_B
4   NC
5   SCK --4 LCD_SCL ENCODER_A
6   SDA --5 LCD_A0

I think SDA should be LCD_SI, and CD should be LCD_A0.

One last thing, I missed where the xtal tester is. I would like to add that. A xtal upgrade comes when I can get it to work at 8Mhz.

The "Sampling ADC" isn't included yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 24, 2017, 10:57:41 pm
...One last thing, I missed where the xtal tester is. I would like to add that. A xtal upgrade comes when I can get it to work at 8Mhz.
Kübbeler is the keeper of Crystal ball feature at the moment. The Sampling ADC method from K-firm must be enabled as well.

... must have 16mhz xtal as well
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 25, 2017, 10:01:56 am
BTW, there's a nice crystal tester and frequency counter in the extended 644/1284 circuit (see Karl-Heinz' documentation). If I'm not mistaken it should work fine up to 80MHz. And I've got the parts for that already ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: scottie4442 on August 25, 2017, 07:16:58 pm
got my set of 3 boards and they look great, now I have to do a BOM and order the parts for this thing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on August 25, 2017, 08:08:03 pm
Quote
I think SDA should be LCD_SI, and CD should be LCD_A0.

The connection names are from an eBay listing, not sure if they are totally correct. Would the display still work if SDA and CD (LCD_SI and LCD_A0) were reversed? I am asking before I start cutting traces....
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 25, 2017, 08:21:03 pm
LCD_SI is the serial data input and LCD_A0 indicates command or data. If they're swapped the display wouldn't even be initialized. Maybe some voltage level problem? The display seems to run with 3.3V and the pull-up resistors of the rotary encoder in parallel are powered by 5V, I'd guess.
Title: Re: $20 LCR ESR Transistor checker project
Post by: knarfootje on August 26, 2017, 01:11:33 pm
do you have a BOM by a ditributor ? I'm very interessed if you have
Title: Re: $20 LCR ESR Transistor checker project
Post by: scottie4442 on August 26, 2017, 01:44:18 pm
I am going through the schematic and making my own BOM so will take a while. I have made the lunk to the board at oshpark available in an earlier post and when I get the BOM done I will post it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 26, 2017, 01:48:00 pm
Someone has created a public BOM list for Reichelt, but I can't find the URL unfortunately. You should be able to find all parts in Reichelt's online shop, including 0.1% resistors for a reasonable price. If you like to save a few bucks buy displays directly from China.
Title: Re: $20 LCR ESR Transistor checker project
Post by: scottie4442 on August 26, 2017, 01:52:32 pm
Thanks, I am putting together my BOM from mouser, I know cost a little more but I have done a lot of business with them in the past. The display I will probably get from from China as you suggested, the highest cost item is the zip test socket, that thing is $20US, holy crap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: j-man on August 26, 2017, 02:18:06 pm
Hi guys. This thread grew up as an awesome tutorial about ATmega... It's a shame I don't know nothing about programming, I really wish I could learn more.
A couple of quick question: I zapped one of the three ATmega328P input ports of my fish8840 tester, I guess I forgot to discharge a cap... damn. Is it worth to replace the chip, in your opinion? What do I need to send the latest firmware to the new chip, and will it work in that 2014 tester?
Many thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on August 26, 2017, 02:47:18 pm
I zapped one of the three ATmega328P input ports of my fish8840 tester, I guess I forgot to discharge a cap... damn.

When buying transistor testers remember rule 1:  Only buy models with a socketed processor!  You WILL eventually zap the chip and SMD rework is no fun, even if you have the equipment.    Silicon and magic smoke hate humans and will commit suicide just to spite you.

Plus it is easy to swap in a different chip configured with different firmware options compiled in.

Get the ZIF socket from China...  maybe a buck or two.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 26, 2017, 02:58:03 pm
Yes, an ATmega328P is just two bucks. You need an ISP programmer (3 bucks) or an Arduino with the ISP sketch. k and m-firmware work fine with old tester versions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on August 26, 2017, 09:57:34 pm
Found the problem with both the no menu and the bar over the last line. The CS line (pin 11 inter-board) was tied to ground and pin 8,9,10 UNDER the connector as well gound on the soldered side (which I cut when jumpering).

Seems to be working just fine. Need to run the calibration and test a few components. Then comes the 16 MHz xtal.

Thanks again to madires for reminding me to do basic troubleshooting. :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: CustomEngineerer on August 27, 2017, 01:00:15 am
Thanks, I am putting together my BOM from mouser, I know cost a little more but I have done a lot of business with them in the past. The display I will probably get from from China as you suggested, the highest cost item is the zip test socket, that thing is $20US, holy crap.

$20 zif socket? For that price you could buy one of the unassembled kits and just use the zif socket from it. :-DD
As much as I like mouser I would also suggest getting that in addition to the display from elsewhere.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on August 27, 2017, 01:54:14 am
NO need to buy a whole kit, 2 zif socket including shipping for $1.20!

https://www.aliexpress.com/item/2PCS-IC-Test-Universal-ZIF-Socket-14pin-14-pin-dip-2-54mm-IC-Socket-pitch/32506431657.html (https://www.aliexpress.com/item/2PCS-IC-Test-Universal-ZIF-Socket-14pin-14-pin-dip-2-54mm-IC-Socket-pitch/32506431657.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: j-man on August 27, 2017, 01:19:32 pm
Yes, an ATmega328P is just two bucks. You need an ISP programmer (3 bucks) or an Arduino with the ISP sketch. k and m-firmware work fine with old tester versions.

Thanks a lot for your informations. I got a friend that could help me with the programmer... let's see.
Another question: I bought another tester as a gift for a friend, but when I opened the package I found a broken display and the seller has sent me a refund. I'm trying to find a new display: the old looks like an ST7565, but the flat cable has just 12 pins, while the similar displays on eBay and Ali have much larger connectors, with 18 pins or more. Any suggestions are welcome... Many thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 27, 2017, 04:26:07 pm
Yes, an ATmega328P is just two bucks. You need an ISP programmer (3 bucks) or an Arduino with the ISP sketch. k and m-firmware work fine with old tester versions.

Thanks a lot for your informations. I got a friend that could help me with the programmer... let's see.
Another question: I bought another tester as a gift for a friend, but when I opened the package I found a broken display and the seller has sent me a refund. I'm trying to find a new display: the old looks like an ST7565, but the flat cable has just 12 pins, while the similar displays on eBay and Ali have much larger connectors, with 18 pins or more. Any suggestions are welcome... Many thanks.
Probably the cheapest source I've seen mentioned for displays (they are also one of the larger sellers of displays on eBay if you would like to pay a little more for the same thing there)
http://www.buydisplay.com/ (http://www.buydisplay.com/)
This is a search for ST7565 based displays:
http://www.buydisplay.com/default/graphic-display?cotroller_ic=445 (http://www.buydisplay.com/default/graphic-display?cotroller_ic=445)
Tutorial on ST7565's from a reputable source:
http://www.ladyada.net/learn/lcd/st7565.html (http://www.ladyada.net/learn/lcd/st7565.html)
  If you really really want to replace the display exactly, it's probably more simple to just buy the whole clone again. Most of the displays sold come with breakout boards so that people don't need to solder ribbon cables directly. However, IIRC, AliExpress had some sellers listing overpriced components specifically listed as "Transistor Tester replacement [x, y, z]." They usually use whatever hair-brain-idiot brand name they made up to sell a clone (hiland, kkmoon, etc.). These names have absolutely zero meaningful value. Others have had issues with the same unit as you and have posted information. Watch the indexes I created and posted on the last page or 2 of this thread to find this information visually.
   As an inexperienced hobbyist myself, I would attack this replacement display issue from a different perspective. Simply look at the issue from the perspective of someone that is building the device from scratch. Look at the documentation on the official PDF and add any display you like. Simply trace out and note the pinout you already have on your PCB and match it to the documentation then pick a matching display or solder wires yourself to add whatever you want. The makefile (a page that walks you through all of the code options step by step) will help you figure everything out to configure the code to match any display options with a supported controller (see official PDF).
  I have been through almost every bit of documentation for this project on all of the different forums. Of all the displays I've seen, I would probably chose one of the NT7108 based units, I haven't had one in my hands but they look huge. The color stuff seems rather silly if you get a chance to see how slow the MCU is at clearing the screen. I plan to record this in a video at some point while comparing the speed with 8, 16, and 20mhz xtals.
Title: Re: $20 LCR ESR Transistor checker project
Post by: j-man on August 28, 2017, 10:30:13 am
Many thanks for your suggestions and for the links, I'll check them out ASAP.
I'm trying to find the "replacement" display because, as you probably read, I have two damaged testers: one with a zapped chip and one with a broken display. And of course I tried to put together the good board and the good display... it works, but the display is vertically flipped.
I thought it was easier buying a new chip and programming it from scratch, instead of trying to modify existing parameters... but I could be wrong, I'm a perfect newbie in that area.
The main reason, to be honest, is that fixing both testers would be quite gratifying...  ;)
I understand your point and I see the advantages about using "any" display. But it would be a whole new challenge for me... I'm not sure I could manage to get through it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 28, 2017, 11:14:34 am
You can flip (horizontally & vertically) or rotate the ouput with most display drivers by enabling that in the Makefile (k-firmware) or in config_328.h (m-firmware).
Title: Re: $20 LCR ESR Transistor checker project
Post by: j-man on August 28, 2017, 11:44:53 am
Yes, thanks, I read it on the manual (page 49-50)
I'll try to get an ISP programmer and play wih it, although I'm still tempted by the other way... trying to get a new display and a new chip.
Thank you guys, this forum is great.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 28, 2017, 12:53:07 pm
Of all the random things... I'm on eBay wasting time when all the sudden it "suggested this (http://www.ebay.com/itm/171630124202).

... I guess the ad spys are now trying to manipulate people to share products with others... I was looking at frequency counter auctions when this was suggested.

 Further information: The eBay listing calls this model of a graphic monochrome display a LX-12864B11 LX12864B11 12864B11 (I'm creating search variations here for others to find this easier). This model appears to be the 12 pin connector version if all of the documentation is correct. I have included screenshots of the listing, pictures, and description to keep this information long term.
 I did a search for the part number and it is available from multiple sources. Interestingly it appears to use a ST7567 display driver. One of the links I found while doing a quick search of the LX part number is here. (https://wiki.mcselec.com/bavr/ST7567_display_library_-_128x64)
 This lists a library and further information about the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 28, 2017, 01:32:24 pm
BTW I finally decided to break a window and adopt a Penguin on my laptop. I also got on KiCad... (talk about none intuitive software... jeez!) That sent me on a search to see if I could find the original KiCad files from KH's main 328 schematic on the Mikrocontroller AVR thread. I'm not sure if the one on the PDF is something Asco B created or if KH made it. I found a few .sch files and .brd files but I didn't see any that were complete with the library file. I also tried scavenging through the tarball, Nick's files, and the yandex clone page looking for them, but I didn't see anything. I tried to search images for every copy of the schematic I could find. I also searched all 10 pages of the official thread by using a "find on page" search for the terms: KiCad, .sch, .brd, and .lib. I did these same searches here on this thread and didn't find anything. The only thing I think I may have missed is if someone posted them as a .zip file and never used the term KiCad in the post (unlikely).
   I figure it's worth asking if anyone has the KiCad file, has recreated it as it is drawn on the official PDF, or knows where I might find it? I'm only looking for that exact layout or very close to it where I can modify it to match easier than completely reconstructing it from scratch.
Title: Re: $20 LCR ESR Transistor checker project
Post by: j-man on August 28, 2017, 02:10:42 pm
This model appears to be the 12 pin connector version if all of the documentation is correct.

THANKS A LOT! Your help is unvaluable, I really appreciate it.
Looks exactly like mine. Unfortunately they don't ship to Italy  |O
But I found it on AliExpress and bought it at once. The keyword is LX-12864B11.
https://it.aliexpress.com/item/1PCS-LOT-LX-12864B11-12864B11-12864-12864-dot-matrix-LCD-display-green-backlight-FREE-SHIPPING/32640521921.html?spm=a2g0y.search0104.3.2.R3JQIb&ws_ab_test=searchweb0_0,searchweb201602_5_10152_10065_10151_10068_5400011_5430020_5410020_10304_10307_10137_10060_10302_10155_10154_10333_10334_10056_5370011_10335_10055_10336_10054_10059_10332_100031_10099_10103_10102_10052_10053_10107_10050_10142_10051_5380020_10326_10084_10083_10080_10082_10081_10177_10110_10111_10112_5390011_10113_10114_10312_10313_10314_10184_10078_10079_10073_5420011,searchweb201603_2,ppcSwitch_5&btsid=fbb0d204-f883-466a-bc3d-1814f94af4b3&algo_expid=e1ee1526-0cad-4b07-9823-34b24825036a-0&algo_pvid=e1ee1526-0cad-4b07-9823-34b24825036a&transAbTest=ae803_3 (https://it.aliexpress.com/item/1PCS-LOT-LX-12864B11-12864B11-12864-12864-dot-matrix-LCD-display-green-backlight-FREE-SHIPPING/32640521921.html?spm=a2g0y.search0104.3.2.R3JQIb&ws_ab_test=searchweb0_0,searchweb201602_5_10152_10065_10151_10068_5400011_5430020_5410020_10304_10307_10137_10060_10302_10155_10154_10333_10334_10056_5370011_10335_10055_10336_10054_10059_10332_100031_10099_10103_10102_10052_10053_10107_10050_10142_10051_5380020_10326_10084_10083_10080_10082_10081_10177_10110_10111_10112_5390011_10113_10114_10312_10313_10314_10184_10078_10079_10073_5420011,searchweb201603_2,ppcSwitch_5&btsid=fbb0d204-f883-466a-bc3d-1814f94af4b3&algo_expid=e1ee1526-0cad-4b07-9823-34b24825036a-0&algo_pvid=e1ee1526-0cad-4b07-9823-34b24825036a&transAbTest=ae803_3)
They sell ICs as well, including ATmega328P. Minimum order 30 pieces... I asked them if it's possible to add just one to my order, but I doubt they will. Let's see.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 28, 2017, 02:32:13 pm
Unfortunately they don't ship to Italy.
  It never hurts to ask a seller to ship to your country. Sometimes they don't do it because of customs problems, other times it's because of the complication of creating a shipping profile for every country on eBay. I used to run a medium size eBay business. Setting up each country so that the buyer sees reasonably good shipping costs is a pain. Most people only set up the options for the biggest markets, but will happily sell to anyone if asked :)
 I shipped top of the line bicycles around the world this way. Many times I shipped to places I never imagined I would sell to because I told people about shipping quote problems on eBay, and gave them package weight, dimensions, and links to shipping quote sites in the description.

Edit: Glad you found what you were looking for ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: j-man on August 28, 2017, 02:42:11 pm
Italian Mail (Poste Italiane) used to be a nightmare for eBay sellers, even more for us customers. They are slightly and slowly improving the quality of their services, but they still have a long way to go. I'm not gonna write about the customers because I could end in jail  ;)
I can't blame a seller that doesn't ship to my country.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on August 28, 2017, 03:02:37 pm
They are slightly and slowly improving the quality of their services, but they still have a long way to go.

So, someone (customs?  post office?) is only stealing a third of the packages now?  I stopped sending stuff to Italy several years ago when over half the stuff I sent to Italy never arrived in the customer's hands.   I would ship if the customer assumed full liability for the delivery...  the customers seemed to be rather familiar with the problem  And these were relatively small and inexpensive items.   I never had any problems receiving stuff from Italy so I assume the problems tended to originate in customs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: j-man on August 28, 2017, 03:36:19 pm
Last year my brother sent me a laptop keyboard from London. After three months the package wasn't arrived yet...  He went back to the UK post office and reported the issue: I don't know if it's just a coincidence, but a few days later a "Poste Italiane" car stopped by my gate, somebody threw a cardboard through the bars and rushed away (by chance I was looking at the window...). Of course the cardboard was half-opened, there was some masking tape on the edge... but at least my keyboard was there. Guess I've been lucky.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 29, 2017, 10:47:11 pm
Can someone thoroughly check my work please? Is there anything I need to change before uploading the KiCad file on the official replica? (the second one is taken directly from the tarball)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on August 30, 2017, 12:44:27 am
You are missing a junction dot at AVCC, C3 and Vcc
Title: Re: $20 LCR ESR Transistor checker project
Post by: v81 on August 30, 2017, 08:12:55 am
I ordered the TFT unit on eBay a week or 3 ago and it recently arrived, have built it and had a struggle with the layout, which lead to this thread.
It's working now, but must say i'm blown away by the info here.

Based on the bits & pieces i've read so far it appears other firmware is available, would love to get hands on it.
Could someone link me the best place to get the latest firmware for these?

Am also interested in building a new unit with better componentry and tighter tolerances, even using 1206 or 0805 SMD and an ATMEGA328P QFP.
Has anyone considered this? would make a great SMD project.

Lastly, an issue, i'm finding the menu is incredibly sluggish, and 'misses' some detents when turning the encoder.
Is this normal?
Would swapping to a 16 or 20 MHz Xtal solve or at least improve the performance?

Thanks in advance for any answers!
- pic of my particular unit....




Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2017, 10:00:08 am
Can someone thoroughly check my work please? Is there anything I need to change before uploading the KiCad file on the official replica? (the second one is taken directly from the tarball)

I suggest to move C10 to the LDO because it's the LDOs output cap. The MCU has its local 100nF bypass cap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2017, 10:29:46 am
Based on the bits & pieces i've read so far it appears other firmware is available, would love to get hands on it.
Could someone link me the best place to get the latest firmware for these?

k-firmware: https://github.com/svn2github/transistortester/tree/master/Software/trunk
m-firmware: https://github.com/svn2github/transistortester/tree/master/Software/Markus (read the README!)
documentation: https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf

Am also interested in building a new unit with better componentry and tighter tolerances, even using 1206 or 0805 SMD and an ATMEGA328P QFP.
Has anyone considered this? would make a great SMD project.

Of course  ;) There are several SMD versions of the tester already. 

Lastly, an issue, i'm finding the menu is incredibly sluggish, and 'misses' some detents when turning the encoder.
Is this normal?

Crappy rotary encoder? A knob could possibly help.

Would swapping to a 16 or 20 MHz Xtal solve or at least improve the performance?

A higher clock rate improves some time related measurements and helps with colour displays. You'll have to build the firmware for the specific clock rate and program the MCU. The 20 MHz clock rate is only supported by the m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on August 30, 2017, 01:02:47 pm

Am also interested in building a new unit with better componentry and tighter tolerances, even using 1206 or 0805 SMD and an ATMEGA328P QFP.


Use a socketed DIP processor chip.  That way WHEN (not IF) you blow up the chip it is very easy to replace.  You really don't want to do SMD rework on the processor every time the gremlins attack.  Also, I keep a couple of chips with different firmware configurations handy and can swap them out in a few seconds.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 30, 2017, 02:17:03 pm
I'm trying to do a detailed breakdown of ALL ATmega328 Transistor Tester Options from the minimum system to the full bells and whistles version. Does the following list look correct so far?
Absolute Minimum System
1.) 3× 680R resistors matched within 0.1% 
2.) 3× 470k resistors matched within 0.1% 
3.) 2× 100nF Capacitors (AVCC & AREF to GND)
4.) 1× 10k Resistor (Reset Pin)
5.) ATmega8/88/168/328
6.) Your Choice of LCD + Supporting HW
7.) 0.1% scientific laboratory grade power supply w/5.000 volt output
8.) Push Button
NOTES:
Internal 8MHz Oscillator
Internal Atmega IC Vref

M A I N  O P T I O N S
Interface
Option 1 minimum/required
Push Button
Option 2
2× Push Buttons (Increase/Decrease)
Option 3
Rotary Encoder w/integrated push button
Option 4
Touch Screen (M-firmware Only as of 9/2017)

External DC Supplied Vcc Power
Option 1
0.1% scientific laboratory grade precision power supply w/ 5.000 volt output
Option 2
5 Volt Regulator w/ better than 0.4% precision
Option 3
5 Volt Regulator + 0.1% Precision Voltage Reference IC

Battery Based Vcc Power
Option 1
On/Off Switch + Test Button(s)
Option 2
MCU Controlled Timed Shutoff w/ Supporting Hardware + Push Button
Battery Option A
9 Volt Battery + LDO 5 Volt Regulator w/ better than 0.4% precision
Battery Option B
9 Volt Battery + LDO 5 Volt Regulator + 0.1% Precision Voltage Reference
Battery Option C
3.7v Lithium Battery + Boost Converter + LDO 5 Volt Regulator + 0.1% Precision Voltage Reference

Oscillator
Option 1
Internal 8MHz
Option 2
External 8MHz Xtal
Option 3
External 16MHz Xtal
Option 4 (M-Firmware Only)
External 20MHz Xtal
Option 2-4A
Standard oscillator Capacitors (~20pF)
Option 2-4B
1× Standard oscillator Capacitor + 1× Trimmer Capacitor ~0-30pF (Requires Frequency Measurement Device w/ Precision Disciplined Reference Oscillator such as a Rubidium Osc or GPSDO)

LCD Variations
~HD44780 (16×2/Hitachi Character)
~ST7036 (Dog-M)
~PCF8812 (Nokia 3410)
~PCF8814 (Nokia 1100)
~PCD8544 (Nokia 3310/5110)
~SSD1306 (microscopic size-OLED)
~NT7108 (Graphic Mono)
~ST7565 (Graphic Mono)
~LCD2004 (20×4 Character)
~ST7735 (Graphic Color 🐌)
~ILI9341 (Graphic Color 🐌)
~ILI9342 (Graphic Color 🐌)
~ST7920 (Giant Graphic Mono)

Additional Auxiliary Features Options
 ~TVS Array/Relay Circuit Protection
 ~Frequency Output
 ~Voltage Measurement (0.1-50 Volts)
 ~Zener Threshold Testing
 ~Infrared Remote Frequency ID
 ~Xtal Measurement (K-firmware)
 ~Optocouple IC Tester
 ~PWM LCD Backlight (LM339 based)
 ~UART Serial Communication
 ~Solenoid Tester
 ~Direct External Frequency Measurement
 ~High/Low Freq. Measure w/Buffer&Prescaler
 ~Self Calibration Capacitor Circuit
 ~Sampling ADC Relay+Capacitor (K-FW Only)

Unofficial/None Supported Auxiliary Features
  ~Bluetooth Serial Communication
  ~LC Meter Circuit (LM311)
  ~LC Meter Circuit (ATtiny3213)
  ~Xtal Test Circuit (PIC16F628A)

The idea is to subdivide every extra circuit option on a schematic... you will see ;)
 With this level of breakdown I should  be able  to explain everything from the 328 version visually without language. Basically I'm creating an ikea instructions type version of the pdf.

Note: This list has been edited to account for all posts of mistakes and omissions after this one as of September 15 2017.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 30, 2017, 05:44:21 pm
Wow, Jake, that's a lot of info once it's all put in a nice list like that. Overall, it seems OK. One correction: the rotary encoder has an integrated push button (i.e., rotate to change value, press to select).
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 31, 2017, 06:16:18 am
Russian Thread part 2... finally. I got 4 corrupt images that gave me troubles, then uploaded a complete video just to find out someone pulled some copywrite shenanigans on a song from 1937....I deleted the whole thing and redid it instead of letting that joker force me to monetize an OS project reference like this.
  The first Version 2 testers are on part 2 Including a really nice ATmega644 DIP version created by Nick, Ocela, and GMS. This  section of the Russian forum thread included a lot of testing and comparisons. I tried to separate these images into a second half of the video and sped them up otherwise the video would be too long.
https://youtu.be/UKjD-Y0iqHY (https://youtu.be/UKjD-Y0iqHY)

The playlist of all 7 I've made so far (https://www.youtube.com/playlist?list=PLPIwHuVy9EyMXIBZ7wwlBu1o0PXTrpG_s)
-Jake
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 31, 2017, 09:43:17 am
M A I N  O P T I O N S
Interface
Option 1
Push Button
Option 2
Rotary Encoder

Actually the test push button isn't an option, it's always required. But we go more options:
- two push buttons (increase/decrease)
- touch screen (m-firmware only)

Additional Auxiliary Features Options

 ~TVS Array/Relay Circuit Protection
 ~External Frequency Measurement
 ~Frequency Output
 ~Voltage Measurement (0.1-50 Volts)
 ~Zener Threshold Testing
 ~Infrared Remote Frequency ID
 ~Xtal Measurement
 ~Optocouple IC Tester
 ~PWM LCD Backlight (LM339 based)
 ~UART Serial Communication
 ~Solenoid Tester

And some more:
- self-adjustment cap
- relay with cap for Sampling ADC

For frequency measurements there are two options. One simple one directly connected to T0, and an extended one with LF/HF crystal oscillators, input buffer and prescaler.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 31, 2017, 03:03:08 pm
Actually the test push button isn't an option, it's always required.
I don't want this to read like I am trying to contradict or anything  like that. I'm certainly no expert at these things by any stretch. I am simply exploring my own curiosity and using this device as a broader learning platform where I have the wonderful resource of smarter people than myself that I can ask for help on a few details while I try to give back by sharing my notes as I go.
  That said, why did Markus Frejek write "(optional)" next to the test button on one of his first schematics of the project? (image attached)
  That was my reasoning point for this statement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 31, 2017, 03:51:03 pm
For the first schematic the push button is optional because that tester is switched on by a separate switch. The second schematic requires the push button for switching on the tester. And the current design of the power control is based on the second schematic. You could still use a power switch if you modify the power circuit, but you wouldn't be able to use the menu and other functions controlled by the push button.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MLXXXp on August 31, 2017, 09:24:22 pm
Absolute Minimum System

I believe you're missing a 10K potentiometer for the LCD display contrast control.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on August 31, 2017, 11:02:48 pm
@MLXXXp
Your certainly correct. I have been debating how to address displays. I don't want a beginner that's even greener behind the ears than me, to think that there is anything special about a 16×2 LCD. I just haven't 100% figured out how I can convey that message visually yet. I went ahead and neutralized the LCD under min sys though. Thanks for the heads up.

   I'm working on overlapping schematics where I can explore/demonstrate the different parts of the circuit in a video. This should allow me to show every detail of the circuit in depth bit by bit.... Still trying to figure out how I want to do the displays though :)

Revised Main Schematic J1.0 attached along with my 1st draft of a minimum system on the same layout (parts are based on Tom666's 1.7 design and Schematic sans voltage regulator)

Edit: I already see I need to take the junction off of the DC input connector. |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 01, 2017, 04:41:45 pm
Did anyone else notice this little bit of Russian magic? I could be totally oblivious, and this may have already been discussed here, although I don't remember seeing it.
  Ocela used the Zener threshold circuit to rig up a way to test linear regulators around pages 138-139 of the main VRTP.ru TT thread. Indman summarized it on his summary thread here (http://vrtp.ru/index.php?showtopic=26994&st=0#) (Russian)
 I tried to clean up the English G-Translate of Indman:
The principle of checking the output voltage of linear regulators L78 XX is shown in the image (L78xx.jpg) below. The jumper is used to select the mode of the voltmeter:
1. Test Zener diodes (jumper)
2. Test L78 XX (no jumper)
To test low voltage linear regulators (e.g. L78L33 ) you need to be aware of their high input voltage breakdown. It is necessary to lower the Vext (external voltage from boost converter, aka zener threshold test circuit) to limit the threshold voltage. This problem is solved by connecting a zener in parallel (output = 7-10V..)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 02, 2017, 04:53:06 am
I will try to finish matching up a revised PCB diagram for the AY-AT with parts delineators tomorrow and I still need to double check it against this schematic. Is there anything I should improve to make this layout more conventional, or easier to understand?
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on September 02, 2017, 07:29:55 am
I have finally got around to testing my upgraded tester. 1.11k GM328 no rotary, no ISP to 1.29m with rotary, ISP.

A few of things -
Tested some known good 2n3055 (various vintage) and house numbered RCA 2n3055 (3700161). The 1.29 shows lower gain, higher leakage, and a few tested as either a cap or two resistors. One tested as a JFET. Two had B-E resistors (7k & 8k), no gain listed and C-E diodes.

Tested a batch of germanium 2n404. The gain and leakage were not near the 1.11 reading. No pattern in the difference. Also 3 of the 14 tested as Pch JFET with 1uA of Idss. Retesting them, two read as PNP BJT with near the same readings as 1.11 about half the time, JFET the other half, and the one still as a JFET.

An MCR92-3 (To-92 plastic) on 1.11 tested as a NPNp, hFE=667,Vf=.727  on 1.29 as BJT PNP+, hFE=20, Vbe=.801

Three Fairchild (I think) dual NPN (2455100 C 205) had gains of about 100 on 1.11 and 80 on 1.29. Pain to test with very short pins.

Why the large discrepancy? I can see small differences but 1/2 the gain and higher leakage when the only difference is the atmel chip?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 02, 2017, 02:54:57 pm
I have finally got around to testing my upgraded tester. 1.11k GM328 no rotary, no ISP to 1.29m with rotary, ISP.

A few of things -
Tested some known good 2n3055 (various vintage) and house numbered RCA 2n3055 (3700161). The 1.29 shows lower gain, higher leakage, and a few tested as either a cap or two resistors. One tested as a JFET. Two had B-E resistors (7k & 8k), no gain listed and C-E diodes.

Have you run the self-adjustment incl. measuring a film cap a few times? Are you powering your tester with a SMPSU? Contact problems? The BJT detection is fairly reliable for Si types, even without the self-adjustment. Are you sure that the two transistors with B-E resistor and freewheeling diode are 2N3055? Typically those types are high voltage switching BJTs for CRTs.

Tested a batch of germanium 2n404. The gain and leakage were not near the 1.11 reading. No pattern in the difference. Also 3 of the 14 tested as Pch JFET with 1uA of Idss. Retesting them, two read as PNP BJT with near the same readings as 1.11 about half the time, JFET the other half, and the one still as a JFET.

Self-adjustment? I have no 2N404 for testing but all my Germanium BJTs (mostly AC1xx) test fine.

An MCR92-3 (To-92 plastic) on 1.11 tested as a NPNp, hFE=667,Vf=.727  on 1.29 as BJT PNP+, hFE=20, Vbe=.801

That would be a BJT with a freewheeling diode on the same substrate as the BJT. Usually the one with the higher base-emitter capacitance is the correct type. Otherwise it's a 50/50 chance. The hFE can differ hugely based on which type is assumed. Have you seen table 5.3 in Karl-Heinz' documentation? Please note the results for BUL38D.

Three Fairchild (I think) dual NPN (2455100 C 205) had gains of about 100 on 1.11 and 80 on 1.29. Pain to test with very short pins.

Why the large discrepancy? I can see small differences but 1/2 the gain and higher leakage when the only difference is the atmel chip?

Again, self-adjustment? Have you compiled the k-firmware with both hFE measurement methods enabled or just the standard one? Have you tried a current k-firmware?

If you find problematic transistors please send me some samples. I'll happily investigate to improve the detection. But I don't got a crystal ball ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: edavid on September 02, 2017, 04:37:32 pm
An MCR92-3 (To-92 plastic) on 1.11 tested as a NPNp, hFE=667,Vf=.727  on 1.29 as BJT PNP+, hFE=20, Vbe=.801

That would be a BJT with a freewheeling diode on the same substrate as the BJT.

It's an SCR.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 02, 2017, 05:16:16 pm
I've found only a datasheet for a MCR 100. The gate trigger current is just 200µA. Is the MCR 92 similar?
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on September 02, 2017, 06:49:17 pm
I ran the self adjustment. I used polyester caps. I am using a 9V battery (new Duracell). The 1.11 is the original chip for my tester, so I have not tried other K firmwares, not sure about the settings in the chinese version.

The 3055 that showed the diodes were marked 2N3055, no HV marking. Bought a bucket of them (literally a bucket, 3 gallon size) in the 90s for $5.

I am going to reflash the chip, want to add a couple of more options. And retest these and some other parts I dug out- UJT, PUT, some odd ball diodes.

Thanks madires.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on September 03, 2017, 10:25:06 pm
Except for the few problem transistors the 1.29m firmware is working for me.

I finally got 1.11m to compile and work. The rotary is a few seconds behind and backwards. The problem germaniums gave the same readings as the original chip.

Compiled 1.13k and the rotary will not work, and sometimes the switch as well. Get the same readings as 1.11m, 1.11m-Chinese on the problem parts.

These flags are commented-
#CFLAGS += -DNO_COMMON_COLLECTOR_HFE
#CFLAGS += -DNO_COMMON_EMITTER_HFE
Title: Re: $20 LCR ESR Transistor checker project
Post by: Giox040 on September 04, 2017, 02:45:01 pm


Would swapping to a 16 or 20 MHz Xtal solve or at least improve the performance?

A higher clock rate improves some time related measurements and helps with colour displays. You'll have to build the firmware for the specific clock rate and program the MCU. The 20 MHz clock rate is only supported by the m-firmware.

Hi !

I also just built the same model and found the slowness of the display and I thought I would pass a quartz by 16MHz, but yesterday I was reading the manual:
TransistorTester with AVR microcontroller
and a little more
Version 1.13k
Karl-Heinz K ubbeler

and on page 55 I found this sentence:

Quote
OP MHZ tells your software at which Clock Frequency in MHz your Tester will operate. The
software is tested only for 1MHz, 8MHz and additionally 16MHz. The 8MHz operation is
recommended for better resolution of capacity and inductance measurement.
Example: OP MHZ = 8

If that is true, I think a slower display but a better resolution is preferable.



Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 04, 2017, 05:24:58 pm
I finally got 1.11m to compile and work. The rotary is a few seconds behind and backwards. The problem germaniums gave the same readings as the original chip.

Compiled 1.13k and the rotary will not work, and sometimes the switch as well. Get the same readings as 1.11m, 1.11m-Chinese on the problem parts.

You can swap the encoder's pins in the k-firmware by setting CHANGE_ROTARY_DIRECTION or by changing ROTARY_1_PIN and ROTARY_2_PIN.

These flags are commented-
#CFLAGS += -DNO_COMMON_COLLECTOR_HFE
#CFLAGS += -DNO_COMMON_EMITTER_HFE

That enables both hFE measurement methods.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 04, 2017, 05:32:37 pm
and on page 55 I found this sentence:

Quote
OP MHZ tells your software at which Clock Frequency in MHz your Tester will operate. The
software is tested only for 1MHz, 8MHz and additionally 16MHz. The 8MHz operation is
recommended for better resolution of capacity and inductance measurement.
Example: OP MHZ = 8

If that is true, I think a slower display but a better resolution is preferable.

That surprises me because with 16 MHz the time resolution is doubled and both measurements (capacitance & inductance) are basically time measurements. I'd assume that Karl-Heinz forgot to update the last sentence.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on September 04, 2017, 07:43:37 pm

You can swap the encoder's pins in the k-firmware by setting CHANGE_ROTARY_DIRECTION or by changing ROTARY_1_PIN and ROTARY_2_PIN.
....
That enables both hFE measurement methods.

I did change the settings in the current version to match the 1.11m version with the 2 second delay, didn't work. Also tried other settings as well and the select button stopped selecting. I am thinking the encoder is junk and your version somehow compensates for that.

I can send you the three 2N404 for testing if you like.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Zad on September 05, 2017, 11:55:39 pm
159 Forum pages and Dave doesn't seem to know this amazing little thing even exists?
Title: Re: $20 LCR ESR Transistor checker project
Post by: zarkov on September 06, 2017, 12:28:42 am
Hi Everyone!

I've already red more than the last 30 pages of this thread, trying to find any recent ebay auction link that would be a "sure bet" for buying the best "bang for the bucket" version of the $20 LCR ESR transistor that can be bought today.

If anyone bought it recently from ebay, I would truly appreciate any recommendation! Sometimes what is announced on ebay auction have some hidden tricks...so buying from an already "tried" and trusted seller would be a much better choice!

Thanks in advance for any answer!
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 06, 2017, 02:03:32 am
159 Forum pages and Dave doesn't seem to know this amazing little thing even exists?
Dave's well aware of any thread that has a million views. There are banner ads running on here ;)
  The 159 pages here are nothing the Russians have 405 pages currently.

If anyone bought it recently from ebay, I would truly appreciate any recommendation! Sometimes what is announced on ebay auction have some hidden tricks...so buying from an already "tried" and trusted seller would be a much better choice!

Thanks in advance for any answer!
   The cheapest market is AliExpress. No Chinese clone meets the minimum hardware design of the device. You want a replaceable dip packaged MCU. I would choose between the AY-AT and the "Little "t" version that looks similar. I posted the parts needed a few pages back if you want to replace the incorrect components on it. Getting it right with a clone is still going to cost you around $30-$35 USD.
   This seller's listing (http://www.ebay.com/itm/112384777217) has been quoted many times before, mostly because almost all of the clones are in this listing and are fairly well priced (I've never ordered from them).
  The best clone is the one you build yourself from scratch. Although understandably, it is probably cheaper to buy and correct a poor design.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on September 06, 2017, 02:17:19 am
159 Forum pages and Dave doesn't seem to know this amazing little thing even exists?

Yah, if he has known, this would be in his 121GW meter and I /we could have have a reason to load up yet another of this tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 06, 2017, 02:32:17 am
Attached is AY-AT Schematic and PCB Reference. I'm working on showing the full retrace now in a video. This one should be error free... I think.. I've triple checked not that that means a whole lot.
  I'll upload the full KiCad file soon as well.... As soon as I'm sure of how to do that correctly.
(https://lh3.googleusercontent.com/-_fICQSJROaI/Wa9b94Q4EBI/AAAAAAAAAcU/pnZme7TUxmUu1pieDnubQBr9dDIVv0X1gCHMYCw/s1600/S01.png)
(https://lh3.googleusercontent.com/-T6VZFJ4FedA/Wa9b8zR6XAI/AAAAAAAAAcM/9W1gEIvdyOEg44V5957d_GjVkZmt3OoEACHMYCw/s1600/S79.png)
(https://lh3.googleusercontent.com/-kLcm_NvHFLQ/Wa9b-Q83xEI/AAAAAAAAAcY/WFGHgk66xkAPRNlVY_sQg731mRB9RII-ACHMYCw/s1600/01.png)
(https://lh3.googleusercontent.com/-CxIY_fcsW8k/Wa9b9QAinPI/AAAAAAAAAcQ/Nzvg-HsZ8V0kxFqrx5_6xCPRmdsQTXt_gCHMYCw/s1600/79.png)
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEVblog on September 06, 2017, 03:15:07 am
159 Forum pages and Dave doesn't seem to know this amazing little thing even exists?

It's a 4 year old thread.
There are 800 posts a day on the forum, so it's kinda hard to keep up.
I'm not exactly watching the top 10 topics stats all the time.
And quite frankly it's not a hugely interesting forum topic to me. I've no doubt seen it few times over the years but if it shows up on the "Unread Posts", my subconscious scan is just going to skip it.
Video coming shortly...
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEVblog on September 06, 2017, 03:18:45 am
159 Forum pages and Dave doesn't seem to know this amazing little thing even exists?
Dave's well aware of any thread that has a million views. There are banner ads running on here ;)

The top forum threads are trivial in the scheme of things when it comes to daily views.

Of the top treads, the Batteriser one would be the only I follow.

(https://i.imgur.com/8DQnTh1.png)
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on September 06, 2017, 03:30:53 am

Of the top treads, the Batteriser one would be the only I follow.


I've developed a Betterizer...  whatever you connect it to, it makes it better!   Care to order a dozen?  I'll toss an extra one in for free.   It can even make itself better!  Don't connect more than two, though.  The world can't handle anything that freakin' good. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: ez24 on September 06, 2017, 03:31:33 am
Video coming shortly...

Waiting ...

Title: Re: $20 LCR ESR Transistor checker project
Post by: EEVblog on September 06, 2017, 03:38:34 am
https://www.youtube.com/watch?v=7Br3L1B80ow (https://www.youtube.com/watch?v=7Br3L1B80ow)
Title: Re: $20 LCR ESR Transistor checker project
Post by: oakkar7 on September 06, 2017, 06:05:45 am
Hi all,

Dave's video version is the same as mine, + come with acrylic case.
First to admit that I am a lazy bone to read all 159 pages forum's pages.  :=\  :palm:

So, the question is "any better firmware update for this model?"

(https://img.banggood.com/thumb/water/oaupload/banggood/images/4D/6C/98d83275-7ae8-4bfc-8296-0f3f2423a488.jpg)

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 06, 2017, 06:42:59 am
FAQ within 5 min
1.) Who designed the device?  Markus Frejek

2.) Where can I find updated firmware?
2 versions are hosted on the Deutsch Forum where the project originated.
Download the zipped tarball here (https://www.mikrocontroller.net/svnbrowser/transistortester/)

3.) Who creates these files?
Markus R. (m-firmware)
Karl-Heinz K. (k-firmware)

4.) What is the best device to buy?
The one you build yourself using the tarball file from above.

5.) I'm too lazy and cheap to build it from scratch. What do I look for in a clone?
a.) 3× 680ohm resistors @0.1% tolerance
3× 470k resistors @0.1% tolerance
b.) Low Dropout Voltage Regulator with 0.5% accuracy or better OR less accurate LDO PLUS a precision voltage reference with 0.5% accuracy or better.
c.) ATmega328 with a replaceable dip package
d.) 6 or 10 pin "In Circuit Programming" header (ISP)

6.) I'm not very smart and I get distracted by pretty things. What's with all the different screen options? What's the best one?
a.) The graphics display makes the unit noticeably slower. Several screens are supported in the official firmware.
b.) Both the alphanumeric and graphics screens do the same thing unless you speak a character based language such as many languages from Asia.

7.) I'm still very confused, and I'm starting to feel impatient with you. What is the latest cheap clone I should look for?
 The 'names' of clones are non-existent. The latest mass produced version (2017) comes with a red PCB that is often incorrectly called a M12864 by sellers. The variation that is sold with a frequency counter and Square Wave PWM output is usually considered the 'latest pretty version.' This version reliably comes equipped with an ATmega328 and is already configured with most project accessory options. Forum members often call it "AY-AT" because this has been printed across a few variations. The easiest way to search for it online is terms like "Transistor Tester PWM" or "tester PWM."

8.) What compromises am I making with this latest clone?
a.) 1% probing resistors instead of 0.1% on most kits
b.) 1% Voltage Reference instead of better than 0.5%
c.) No ISP header so you must remove the microcontroller to update the firmware.

9.) I'm too lazy to open the tarball file, and I still have a question.
***Here***  (http://www.avrtester.tode.cz/upload/ttester_en.pdf) is the official PDF documentation from an older tarball file from May 2017.

10.) Lol, I'm not about to read all of that... it doesn't have enough pictures. I think I'll just ask a stupid lazy question in this forum.
Use search first. Then read at least the page here:
https://www.mikrocontroller.net/articles/AVR_Transistortester (https://www.mikrocontroller.net/articles/AVR_Transistortester)
Then read the last 10 pages of this thread minimum before asking the same questions from the last couple of pages.
  This forum is followed regularly by Markus R, the developer of the m-firmware. He likes to help people, as do many others here. We would all like the project to continue as long as possible, so please don't waste everyone's time asking the same questions dozens of times.

Note: I think this device is too simple. I assume it must be designed by amateurs. I know just how to improve it and I can't wait to tell everyone here about it before I read the details about the project...

  This project is an exercise in maximizing the potential of the ATmega microcontroller's internal hardware using a combination of C and Assembly.
  The firmware developers are more than capable of designing and integrating improved hardware options. However, they are not interested in creating a project where people must continuously "buy" the latest/greatest product. They have stated, 'If/when they feel they can no longer improve the project any further through software, they may consider creating a Tester+ version.'
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 06, 2017, 06:58:19 am
The picture flipbook summary of pages 1-150 of this thread:
EEVBlog Transistor Tester Thread
Part 1 of 3
https://youtu.be/on1ZrWNt2Us
Part 2 of 3
https://youtu.be/RRJ5K752d18
Part 3 of 3
https://youtu.be/1ARlc1BHLUw
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 06, 2017, 08:32:15 am
Attached is AY-AT Schematic and PCB Reference.

It is correct 22pF? Original schematik 100nF
Title: Re: $20 LCR ESR Transistor checker project
Post by: b_force on September 06, 2017, 08:34:49 am
Great music btw!  :-+

Bit of a sarcastic post.
I think what's missing is a very clean, easy to read and understandable summary.
Although I can imagine the frustration, not everyone has the time to read (and understand) a 130 page counting document.
A topic with a first post that is being updated regularly also works.

So my suggestion, write a short second document with a brief summary and little table with specs and differences in firmware versions/variations.
Unless you're really into the project it's a bit of maze imo (nofi btw)  :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElektroQuark on September 06, 2017, 08:44:50 am
Quote from: jakeisprobably on Today at 06:42:59 (https://www.eevblog.com/forum/index.php?topic=14399.msg1295784#msg1295784)

>FAQ within 5 min
...


Thank you very much, jakeisprobably.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 06, 2017, 09:05:18 am
Bit of a sarcastic post.
   It's intended as a joke. If you read a considerable amount of the thread you'll feel the same. Also if you were to pay attention to my first posts... I'm actually making fun of myself. I made all of these lazy/stupid mistakes.
Quote
...write a short second document with a brief summary and little table with specs and differences in firmware versions/variations.
  I've been working on it for awhile, but I'm a slow partially disabled gimp. I wrote that FAQ a month ago. I have a lot more info complied but I need to collect a bit more information first. There will be a new thread here with a better organized first post eventually.
This post has all ATmega328 project options listed (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1291268/#msg1291268)
@Indman your correct I must have copied that capacitor and forgot to change the value, sorry.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tooki on September 06, 2017, 09:59:57 am
Re: jakeisprobably's awesome FAQ, #8:

Does that mean I can improve the accuracy of my T4 by replacing some components with better ones?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Giox040 on September 06, 2017, 10:28:09 am
Hi!

Can anyone recommend me a DC-DC step up from 5-9V up to about 25V for Z-Diode test to buy on ebay?

Thank in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 06, 2017, 10:47:28 am
Can anyone recommend me a DC-DC step up from 5-9V up to about 25V for Z-Diode test to buy on ebay?

A good DC/DC converter would be MEA1D0515SC from muRata. I recommend to power it by a separate LDO with proper decoupling. Please see the ATmega 644 schematic in Karl-Heinz's documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mr. Scram on September 06, 2017, 08:21:06 pm
https://www.youtube.com/watch?v=7Br3L1B80ow (https://www.youtube.com/watch?v=7Br3L1B80ow)
I very much appreciate the willingness to admit a mistake, and having a second look, regardless of the conclusions drawn.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 07, 2017, 12:55:26 am
Does that mean I can improve the accuracy of my T4 by replacing some components with better ones?
Probably. The device will perform to spec if built to spec, but I'm no expert.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BradC on September 07, 2017, 06:35:09 am
I just want to say a serious thanks to everyone in this thread (with a special shout to madires).

I have two of these:
http://www.ebay.com/itm/M328-LCD-12864-DIY-Transistor-Tester-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter/161913228003?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649 (http://www.ebay.com/itm/M328-LCD-12864-DIY-Transistor-Tester-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter/161913228003?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649)

I bought two because 5 minutes into my use of the first one I put it across a cap that still had ~50V in it and popped the uC. I ordered another kit and just swapped the uC in.

Yesterday I bought a couple of new 328P chips, bodged an ICSP header onto my built unit, grabbed the latest source tree, read the instructions, and built & loaded the firmware into the unit. I already had a $2 e-bay USB-ASP clone lying around. It worked first try. The documentation is good, the build configuration is good and man if it wasn't dead easy. So thanks madires!

On another note, this kit comes with 0.1% measure resistors, a ht7550 LDO and a TL431 (of some sort). I have a 6.5 digit meter, and the TL431 has been steady for the 6 months I've had/used the device now (well within its specified 100ppm/C. Certainly accurate enough for this use), so if you have the means to measure and put the correct UREF_25 value in, this kit is not too bad out of the box.

This is my first experiment with the AVR, and it was almost easy enough to make me think about using them in lieu of PICs or Propellers in some prototype applications.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ez24 on September 07, 2017, 06:54:40 am
What do you guys think about this one that uses a 18650

https://www.aliexpress.com/item/Free-shipping-New-3-7V-version-of-inductor-capacitor-ESR-meter-DIY-MG328-multifunction-transistor-tester/32613345424.html?spm=2114.search0104.3.119.Uvlbif&ws_ab_test=searchweb0_0,searchweb201602_2_10152_10065_10151_10068_10130_5490020_10307_10137_10060_10155_10154_10056_10055_10054_5470020_10059_100031_10099_5460020_10103_10102_10052_10053_10142_10107_10050_10051_10324_10325_5380020_10326_10084_10083_10080_10082_10081_10178_10110_10111_10112_10113_10114_10312_10313_10314_10078_10079_10073_5550011-10102,searchweb201603_21,ppcSwitch_3&btsid=e424fa78-3354-41f1-88b8-73f37e871fb7&algo_expid=dbdf11c9-75f2-427c-b5b7-94ce3a31a5f3-18&algo_pvid=dbdf11c9-75f2-427c-b5b7-94ce3a31a5f3 (https://www.aliexpress.com/item/Free-shipping-New-3-7V-version-of-inductor-capacitor-ESR-meter-DIY-MG328-multifunction-transistor-tester/32613345424.html?spm=2114.search0104.3.119.Uvlbif&ws_ab_test=searchweb0_0,searchweb201602_2_10152_10065_10151_10068_10130_5490020_10307_10137_10060_10155_10154_10056_10055_10054_5470020_10059_100031_10099_5460020_10103_10102_10052_10053_10142_10107_10050_10051_10324_10325_5380020_10326_10084_10083_10080_10082_10081_10178_10110_10111_10112_10113_10114_10312_10313_10314_10078_10079_10073_5550011-10102,searchweb201603_21,ppcSwitch_3&btsid=e424fa78-3354-41f1-88b8-73f37e871fb7&algo_expid=dbdf11c9-75f2-427c-b5b7-94ce3a31a5f3-18&algo_pvid=dbdf11c9-75f2-427c-b5b7-94ce3a31a5f3)


(jezzz what an URL)

I have many 18650s and no 9v batteries

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on September 07, 2017, 07:47:07 am
This tester DOESN'T use an 18650, it uses an 14500, also a lithium Ion which is the size of a AA and not as popular as the 18650.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on September 07, 2017, 09:17:29 am
There are so many hardware variants based on the exact same core schematic and before everyone rush to buy the variant that Dave reviewed, I think it is better to evaluate which will better fit your needs.

The main difference I considered are:

Thru hole            vs   smt components        If you forget to discharge a capacitor before testing it the THT version can be fixed quickly
Assembled          vs   DIY Kit                      a DIY kit shouldn't be an issue in this forum :)
With push button vs  with rotary encoder    whith the encoder it is easier to navigate in the menu to select specific measurements options (opto, IR, Servo...)
With case            vs  without case              I like the case one

For instance my personal preference is the one that is called Hiland DIY M12864 Kit at Banggood, because it is THT, it has a nice case and it is faster than the color display variant.
I modifyed it to have:
External input voltage
ICSP connector
UART for measurement logging also with Bluetooth....

Mauro

PS: I posted the same message on the thread related to the video posted by Dave, but I think this should belong here.
Link to the other thread
https://www.eevblog.com/forum/blog/eevblog-1020-is-a-$7-lcr-component-tester-any-good/msg1296703/#msg1296703 (https://www.eevblog.com/forum/blog/eevblog-1020-is-a-$7-lcr-component-tester-any-good/msg1296703/#msg1296703)
Link to the enclosures-and-mods thread
https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/ (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/)
Link to the Mailbag thread where also this tester is discussed
https://www.eevblog.com/forum/blog/eevblog-1019-mailbag-94564/ (https://www.eevblog.com/forum/blog/eevblog-1019-mailbag-94564/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Giox040 on September 07, 2017, 10:17:34 am
Can anyone recommend me a DC-DC step up from 5-9V up to about 25V for Z-Diode test to buy on ebay?

A good DC/DC converter would be MEA1D0515SC from muRata. I recommend to power it by a separate LDO with proper decoupling. Please see the ATmega 644 schematic in Karl-Heinz's documentation.

Hi Madiras!
Thanks for the quick reply.
I have seen that the MEA1D0515SC is quite expensive.
I've seen some cheaper converters on eBay, such as the link below here could not be enough?

http://www.ebay.it/itm/DC-DC-Step-up-Boost-Converter-3-3V-5V-9V-12V-2A-Adjustable-Power-Supply-Module-/322449827696?hash=item4b1381e770:g:gT8AAOSwsS1ZjQ46 (http://www.ebay.it/itm/DC-DC-Step-up-Boost-Converter-3-3V-5V-9V-12V-2A-Adjustable-Power-Supply-Module-/322449827696?hash=item4b1381e770:g:gT8AAOSwsS1ZjQ46)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2017, 12:18:18 pm
I can't say anything about that boost converter. Buy and try ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on September 07, 2017, 04:29:06 pm
Quote
Thanks for the quick reply.
I have seen that the MEA1D0515SC is quite expensive.
I've seen some cheaper converters on eBay, such as the link below here could not be enough?

http://www.ebay.it/itm/DC-DC-Step-up-Boost-Converter-3-3V-5V-9V-12V-2A-Adjustable-Power-Supply-Module-/322449827696?hash=item4b1381e770:g:gT8AAOSwsS1ZjQ46 (http://www.ebay.it/itm/DC-DC-Step-up-Boost-Converter-3-3V-5V-9V-12V-2A-Adjustable-Power-Supply-Module-/322449827696?hash=item4b1381e770:g:gT8AAOSwsS1ZjQ46)

I have used a similar one, they are adjustable up to 28V and it works fine.  You can find them on eBay or Aliexpress for less than $1.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 07, 2017, 05:12:12 pm
...or if you want to go cheap and dirty just grab an old car type phone charger as they almost always contain a MC34063, and build a boost converter for free by simply reconfiguring the parts layout and adding a junk bin trimmer pot for one of the voltage divider feedback resistors. Almost any simple peak mode SMPS controller can be reconfigured from the typical buck to a boost circuit extremely easily.
   However the professional modules like Madires suggested are much much higher quality and less noisy as they are designed to create +/-15 volt rails for powering things like op amps.
Over simplified 34063 circuit calculator (http://www.nomad.ee/micros/mc34063a/)
Onsemi SMPS Reference (http://www.onsemi.com/pub_link/Collateral/SMPSRM-D.PDF)
MC34063 pin by pin description (http://www.learningaboutelectronics.com/Articles/Switch-mode-power-supply-circuit-with-an-MC34063.php)
Onsemi MC34063 Design Spreadsheet -Excel file (https://www.onsemi.com/pub/Collateral/MC34063%2520DWS.XLS)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ez24 on September 07, 2017, 05:53:20 pm
This tester DOESN'T use an 18650, it uses an 14500, also a lithium Ion which is the size of a AA and not as popular as the 18650.

Yikes    :palm: :palm: :palm: :palm: :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 07, 2017, 11:11:28 pm
What do you guys think about this one that uses a 18650
If I wanted to get a Lithium powered unit I'd get the "T6."
Like this:
http://www.ebay.com/itm/232333734207 (http://www.ebay.com/itm/232333734207)
That's the evolution of the one that Dave was sent. Unfortunately the screen is color, but you get a bunch of extra circuits like infrared and zener threshold if I'm not mistaken. The unit that Mauroh suggested has a nice case with a monochrome screen, but all of these have surface mount MCU's.
 A quick scan through my files and it looks like the "LCR-T6/TC" was mentioned on pages 103, 112, 128, 146, and 150. Page 150 contains a video that unintentionally shows the color TFT screen clear delay. I believe that is the speed with the 8MHz Xtal, so a 16MHz and recompiled firmware should half that delay. I'm not sure of the difference between the T6/TC but they look similar at a glance.
 I believe the one Dave has is the "LCR-T4" but I could be mistaken. The T4 Schematic is on page 119, and one of the times it was discussed a good bit was on page 38.

Edit: here's a video that shows screen clear delay, and IR remote (no affiliation)
https://youtu.be/8Fk09QxJrh8 (https://youtu.be/8Fk09QxJrh8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ez24 on September 07, 2017, 11:28:19 pm
Quote
7.) I'm still very confused, and I'm starting to feel impatient with you. What is the latest cheap clone I should look for?
 The 'names' of clones are non-existent. The latest mass produced version (2017) comes with a red PCB that is often incorrectly called a M12864 by sellers. The variation that is sold with a frequency counter and Square Wave PWM output is usually considered the 'latest pretty version.' This version reliably comes equipped with an ATmega328 and is already configured with most project accessory options. Forum members often call it "AY-AT" because this has been printed across a few variations.

Searching Aliexpress on M12864 brings up kits.   Searching on AY-AT does not come up.

Does anyone know of a variation that is sold with a frequency counter and Square Wave PWM output is usually considered the 'latest pretty version.   That is NOT a kit?

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on September 07, 2017, 11:47:32 pm
What do you guys think about this one that uses a 18650
If I wanted to get a Lithium powered unit I'd get the "T6."
Like this:
http://www.ebay.com/itm/232333734207 (http://www.ebay.com/itm/232333734207)
That's the evolution of the one that Dave was sent. Unfortunately the screen is color, but you get a bunch of extra circuits like infrared and zener threshold if I'm not mistaken. The unit that Mauroh suggested has a nice case with a monochrome screen, but all of these have surface mount ...
My problem with T6 and the rest of Tx (except early T) is they are surface mount, and the LCD are soldered to PCB.  To reprogram, either you have to desolder the LCD ribbon cables, or to desolder the chip.  after the reprogramming, soldering them back. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 08, 2017, 12:37:17 am
the problem with socketed chips is the contact resistance can change over time.

smd chips are best - fit a programming header.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on September 08, 2017, 12:50:11 am
the problem with socketed chips is the contact resistance can change over time.

smd chips are best - fit a programming header.

No, they are not!  These testers have a known, all to common, failure mode of the chip blowing if you connect a charged capacitor.   The hassles of having to do SMD rework to replace the chip far outweighs potential issues of (minuscule) changes in contact resistance. 

At 0.1% tolerance the 680 ohm resistance is  within +/- 0.68 ohms.  I seriously doubt even a crappy IC socket would change that much... I put screw machine contact sockets in mine.  I also have a few different processors configured with different options and occasionally swap them out... no need to dig out the programmer.  Using SMD processors for these devices is just not the best idea.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jshonw on September 08, 2017, 02:00:32 am
Quote
7.) I'm still very confused, and I'm starting to feel impatient with you. What is the latest cheap clone I should look for?
 The 'names' of clones are non-existent. The latest mass produced version (2017) comes with a red PCB that is often incorrectly called a M12864 by sellers. The variation that is sold with a frequency counter and Square Wave PWM output is usually considered the 'latest pretty version.' This version reliably comes equipped with an ATmega328 and is already configured with most project accessory options. Forum members often call it "AY-AT" because this has been printed across a few variations.

Searching Aliexpress on M12864 brings up kits.   Searching on AY-AT does not come up.

Does anyone know of a variation that is sold with a frequency counter and Square Wave PWM output is usually considered the 'latest pretty version.   That is NOT a kit?

thanks

Try searching  for GM328 on ebay and you should see something like xxxxAY-AT next to the encoder on the board in one of the pictures. 

Something like this one.   Not sure if it contains 0.1% resistors.  Can somebody confirm?
http://www.ebay.com/itm/2017-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator/172557508334?var=471403196090&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D41375%26meid%3D587faf2ced2c4a1986707a5cb50c443a%26pid%3D100005%26rk%3D5%26rkt%3D6%26sd%3D112489435576&_trksid=p2047675.c100005.m1851 (http://www.ebay.com/itm/2017-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator/172557508334?var=471403196090&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D41375%26meid%3D587faf2ced2c4a1986707a5cb50c443a%26pid%3D100005%26rk%3D5%26rkt%3D6%26sd%3D112489435576&_trksid=p2047675.c100005.m1851)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 08, 2017, 02:23:19 am
the problem with socketed chips is the contact resistance can change over time.

smd chips are best - fit a programming header.

No, they are not!  These testers have a known, all to common, failure mode of the chip blowing if you connect a charged capacitor.

so dont - discharge it first.  :-DD

btw, i can swap-out a QTFP package faster than you can swap a chip in a dil socket!
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on September 08, 2017, 02:41:07 am
btw, i can swap-out a QTFP package faster than you can swap a chip in a dil socket!

NO, you can't...  I'll have the chip swapped before your soldering system even warms up.  Then you have to clean up and solder 32 pins.   I just swapped a tester processor chip in under a minute.

And probably 99% of the people buying these things have never soldered a SMD device in their lives, much less removed a 32 pin CPU chip.  And they are also the types that are rather prone to not discharging their caps.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 08, 2017, 03:25:14 am
a min - a whole 60 seconds??

you obviously never watched a pro with a hot-air station, a pair of tweezers and a bottle of flux.
if the station was already on, i could change it twice in that time!
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 08, 2017, 03:35:02 am
Does anyone know of a variation that is sold with a frequency counter and Square Wave PWM output is usually considered the 'latest pretty version.   That is NOT a kit?
AY-AT is what "we call it on the forum." ;)
 To sellers they are all GM328's or Hiland KKmoon thingy madoos. I've tried to to figure out some kind of logic to their naming convention but if you search long enough you will find all of clones called the same things in different places. The names will just limit the sellers you find while searching.
   The easiest way to search is by physical features. If you want almost all AY-AT variations search "Tester PWM" that is an extremely specific and unique term.
Or here's a seller with assembled, kits, or case options in one listing.
http://www.ebay.com/itm/112489435576 (http://www.ebay.com/itm/112489435576)

If you go the AY-AT route be sure to check this post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1291268/#msg1291268) out first.
Edit /\
         |
Correct link (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ez24 on September 08, 2017, 03:40:45 am
Or here's a seller with assembled, kits, or case options in one listing.
http://www.ebay.com/itm/112489435576 (http://www.ebay.com/itm/112489435576)

Thanks  I ordered one assembled with the case for $18
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 08, 2017, 04:23:29 am
I just have to say... it might be worth it to pay $14 for this (http://www.ebay.com/itm/122512436422) $7 tester just to be like Dave:
(https://lh3.googleusercontent.com/-WX0S8wA0IZM/WbIZ6Q2t4eI/AAAAAAAAAc4/UFghkXD5a1gARj-6eE6L6NavtGPIGqZLwCHMYCw/s1600/Down%2Blike%2BDave.jpg)
Such a great relevant contextual image right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 08, 2017, 07:10:53 am
At least that "electrician" isn't trying to hook up the tester to a live, high-energy panel.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on September 08, 2017, 07:55:48 am
Or here's a seller with assembled, kits, or case options in one listing.
http://www.ebay.com/itm/112489435576 (http://www.ebay.com/itm/112489435576)

Thanks  I ordered one assembled with the case for $18

What do you guys think about this one that uses a 18650
If I wanted to get a Lithium powered unit I'd get the "T6."
Like this:
http://www.ebay.com/itm/232333734207 (http://www.ebay.com/itm/232333734207)
That's the evolution of the one that Dave was sent. Unfortunately the screen is color, but you get a bunch of extra circuits like infrared and zener threshold if I'm not mistaken. The unit that Mauroh suggested has a nice case with a monochrome screen, but all of these have surface mount ...
My problem with T6 and the rest of Tx (except early T) is they are surface mount, and the LCD are soldered to PCB.  To reprogram, either you have to desolder the LCD ribbon cables, or to desolder the chip.  after the reprogramming, soldering them back. 

Well done guys :) !!

The point of my message is to encourage all the viewers of the Dave's review to evaluate some of the variants and find the best fit for their needs.
My choice was the best for me the day I evaluate it.

As for me, texaspyro and stj are both right :
If you are good with smt or you don't know how to solder (es. a breadboard man...) go for the smt variant if it will blow up you will fix it (in 24 seconds :popcorn:) or buy another one for 7$
Is there an smt variant with rotary encoder, case and color display already assembled?
I think we need to add a buyers guide in the documentation, something like -> if you want it with the case, this are the current options (or 3d print it), if you want it with the lithium barrery, if you want it with the rotary encoder...

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on September 08, 2017, 09:00:03 am

Is there an smt variant with rotary encoder, case and color display already assembled?
Here it is, it looks like there are a couple of variation of it too.  All of them seem to have a black PCB as opposed to the red, green of yellow PCB.

http://www.ebay.com/itm/LCD-GM328A-Transistor-Tester-Diode-ESR-Meter-PWM-Square-Wave-Generato-Practical-/132281636619?epid=942275376&hash=item1ecc99970b:g:zU8AAOSwtGlZNhE2 (http://www.ebay.com/itm/LCD-GM328A-Transistor-Tester-Diode-ESR-Meter-PWM-Square-Wave-Generato-Practical-/132281636619?epid=942275376&hash=item1ecc99970b:g:zU8AAOSwtGlZNhE2)

Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on September 08, 2017, 10:06:46 am
Thanks for the answer , but It was a rhetorical question, since it is also the one suggested by jakeisprobably and linked in my own post :) (ok, my english is terrible...)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on September 08, 2017, 03:41:06 pm
https://m.intl.taobao.com/detail/detail.html?spm=a230r.1.14.48.76bf523DnoKUs&id=522684133706&ns=1&abbucket=9#detail

This is my choice now.  Hope their sale can go up so they can do a color version.  It is socketed 328.  My mod is adding  a DC socket for power, and a stereo 2.5mm for a 3 wire microclip.

At moment still not selling on ebay, bangoo or amazon. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 08, 2017, 05:05:19 pm
I think we need to add a buyers guide in the documentation, something like -> if you want it with the case, this are the current options (or 3d print it), if you want it with the lithium barrery, if you want it with the rotary encoder...
I agree 100%
I've actually tried several different ways of doing this. The big issue is naming convention. When I posted the message a few pages back about making up our own names for clones, I was actually looking for a response to gauge how others reacted to this. I could call them "Larry, Curly, and Moe," but if no one adopts that naming convention it's a useless reference. In my opinion the names need to be intuitive so that they are easy to recall visually. edit: I am against using anything that sellers have created. Terms that are not present on a PCB or descriptive of the specific clone are useless and confusing to most people, especially people who need simple answers without spending days learning about the project. Any name like hiland kkmoon, m328, gm328, TFT gm328, are none distinct and useless.
   Overall, establishing names is the biggest hurdle. I am still trying to figure out the most effective way to do this.
 Once I have all of the information from the Russian thread, I hope to put together a few videos of:
(Videos are ideal because they don't have image hosting and long term storage problems)
Interesting/Entertaining
1.) DIY projects with 1-3 pics of all projects made from scratch from all forums
Useful Reference
2.) Videos of each major clone and everything visual I have collected on all forums for each one
3.) video of unique clone mods, cases, and hacks
4.) Finish my videos on the AY-AT showing every detail through programming step by step without using any spoken language

I have the FAQ draft you've seen. I also have written linked troubleshooting references (problem summary/link to problem post/link to solution post) for about half of this thread where people have had various problems that were solved. I have a reference written for all screens used, but can't call it completed until I finish the Russian thread. I have the list of all auxillary circuits for version 1. I am also working on a list of all custom projects that are documented with the files included to etch/order your own PCB. I'm working on a list of all ATmega644 and up projects. I also have a list of 'outlaw' projects I've come across that have unofficial auxillary circuits and options.
   I wanted to complete most of this before creating a new thread. I want to do this on a different forum account that I can give to Markus to control. Essentially this would create a locked wiki format within an interactive forum thread as I would create around 10 thread posts immediately after starting the thread, reserving a large amount of room for updating and posting useful information on page 1. I asked, and Dave's fine with it.
...at least that's the plan and what I've been slowly churning away at. I got around 75% done with the info on this thread before I started to see I was missing a lot of relevant material and had to broaden my data set or I would likely misrepresent a lot of information.
 -Jake
PS Why am I doing this/spending a crazy amount of time on this simple device? So Dave can call me a fanboy.... Because after getting a broken neck I spend most of my time stuck laying flat. The only digital device I can use for long amounts of time is a phone. Learning Electronics in general is more fulfilling than dominating at phone games, something I did for a long time when I thought I'd get heal quickly. I can use a device/project like this to learn a broad range of skills, and I'm a bit of a polymath ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 08, 2017, 07:44:43 pm
I'm answering a question from YouTube comments and thought I'd paste the links here:
These describe why the Transistor Tester isn't a replacement for a LCR meter despite what is printed on some PCB silkscreens from China. Some of this information is outdated but still provides insightful perspective. For current capabilities of the device use the explanation in the official documentation.
Why the AVR Transistor Tester is not a substitute for a real LCR Meter
1. "The measurement uses charge/discharge pulses while synchronizing them with the ADC. The 8 and 16MHz testers use the same ADC clock, while the 20MHz got a..." (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1050001/#msg1050001)

2. "...These $20 meters measure resistance and semiconductors as well as capacitance and ESR. They aren't really a replacement for the handheld meters.." (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg530451/#msg530451)

3. "...the doc confirms that the device will only determine ESR for caps over "(xx)". I suspect this is because the frequency is only 680Hz instead of the more traditional 100MHz. Apparently it.." (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg195402/#msg195402)

4. "The inductance measurement is quite limited by the maximum test current and the method used. It even runs the ATmega out-of spec for some µs for low inductances...." (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg432772/#msg432772)

5. Post about other DIY LCR meter circuits (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg526087/#msg526087)

Also EEVBlog thread searching 101
1.) Use the "print" button to create a text only single page version of this thread
2.) After the page loads in your browser, use your web browser's "Find on Page" feature to search for key words.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 08, 2017, 08:01:10 pm
Meanwhile some ranges are obsolete ;) The current k-firmware measures the ESR of caps down to 20nF. And the beta of the next m-firmware down to 10nF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 08, 2017, 08:46:36 pm
3. "...the doc confirms that the device will only determine ESR for caps over 2uF. I suspect this is because the frequency is only 680Hz instead of the more traditional 100MHz. Apparently it.." (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg195402/#msg195402)

100MHz????? dont give up your day job.
(unless it's electronics related!)
 :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 08, 2017, 10:50:41 pm
Meanwhile some ranges are obsolete ;)
Thanks. That's the reason why I keep posting bits and pieces of my notes and quotes over time. It's almost impossible to filter through all of the information in this forum alone and know what is up to date and what is not. It's much easier to get multiple eyes on little bite size chunks.
   Most people probably see that info as pointless, but there are many times when the questions and conversation are broken down in a way that beginners can understand and connect with. I hope to retain some of that ease of access as I try to distil my notes.
    I wasn't aware of the basic functionality of how a LCR meter workes until I read this thread. I just haven't needed one on a project until a couple of months ago playing with DC to DC converters, so I didn't have a reason to figure them out. When I saw a bunch of $10 devices called LCR's and people buying them I figured I'd go that route first... I'd bet the farm I'm not alone on that path. So I approach the subject from that angle. That kind of approach should make a highly effective guide to this device that helps the vast majority of people that are not EE's. I'm sure EE's will find it a bit silly, but the answer to all of their questions is the easiest, even a idiot like me can answer that one: GNU tarball  :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 11, 2017, 12:18:51 am
Just uploaded the complete retrace of the AY-AT.
https://youtu.be/mRMRtrzh6rI
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 11, 2017, 05:25:12 pm
A couple of extra images are attached that show just the top and just the bottom traces with all the same color coding. Most people probably don't have a use for these but it's just one extra dimension to add to the equation.
    I'm using this to learn the PCB side of KiCad. I figure it's easier to start learning by trying to create something similar to what I already have in my hands than it is to try to create a new project from scratch. This is why I haven't uploaded my KiCad files yet. If I can pull it off I should have a PCB clone of a clone soon...and maybe a 3d model... If I can figure out how to do all this stuff :)

Also Notice
   To anyone that may not be aware, I have tried my best to matchup all of my schematics and part designators to the main schematic in Karl-Heinz PDF documentation. This means you can read his detailed information about the project while using the schematics I have shared to learn about this device. This is why the part designators are a bit odd looking at first. I have added extra part designators for the additional circuits on this device. I chose to add these in succession to the existing ones. This has also left a few gaps in the numbers that mirror the gaps in the main schematic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tablatronix on September 11, 2017, 06:40:49 pm
do you have high quality images or front and pack of pcb? I forgot to take some nice flat pictures of the board before I started putting it together,
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 11, 2017, 07:35:37 pm
do you have high quality images or front and pack of pcb?
Not really. I used to have a budget photography studio and a medium sized eBay operation but had to leave all of that to an old business partner due to physical limitations. I do everything in my videos with a phone camera, and makeshift junk. I don't have a proper DSLR or a squared camera setup any more. I could build a square rig with junk I have laying around but phone sensors/lenses introduce too much distortion into the image. This link (http://upcycleelectronics.blogspot.com/2017/09/ay-at-layers.html?m=1) has the series of pictures showing the way I created the top and bottom traces overlay. They are not high quality or square. I only have these images from the sketch app. I don't have the original back images that I chopped up to create it. The bottom image is a composite of 3 images used to Aline everything close enough to follow the traces. The top layer holes were maped on their own layer, then overlayed onto the bottom image. This allowed me to trace the bottom images in a way where I could connect the traces to the top layer holes and make adjustments where needed.
  I started the newest video with these same top/bottom trace maps. I showed this method in more detail in an older video, but I wanted to make something that was easier to follow this time.
  Again, unlike most people, I have an enormous amount of time available to play with this kind of stuff due to physical limitations. I am forced to use a phone for about 90% of anything I want to do because it's light weight and manageable with my injuries. So everything I do is a bit wonky.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 11, 2017, 08:45:38 pm
It's pretty cool what you accomplish with a phone. The schematic-to-PCB tracing video was pretty neat.
Title: Re: $20 LCR ESR Transistor checker project
Post by: edavid on September 11, 2017, 09:30:30 pm
do you have high quality images or front and pack of pcb? I forgot to take some nice flat pictures of the board before I started putting it together,

Here you go...
Title: Re: $20 LCR ESR Transistor checker project
Post by: ez24 on September 11, 2017, 09:50:15 pm
Again, unlike most people, I have an enormous amount of time available to play with this kind of stuff due to physical limitations. I am forced to use a phone for about 90% of anything I want to do because it's light weight and manageable with my injuries. So everything I do is a bit wonky.

Sorry to hear that you are wonky, I also am a little.

Do you like watching YT videos?  I put together this list

https://www.eevblog.com/forum/other-blog-specific/dd/msg1093983/#msg1093983 (https://www.eevblog.com/forum/other-blog-specific/dd/msg1093983/#msg1093983)

And I am working on adding suggested "topics" or "subjects".   For example I will make recommendations on different subjects like scopes, op amps, transistors, etc.

Here is some of the work I have done on Op Amps:
https://www.eevblog.com/forum/beginners/op-amp-youtube-videos-my-list-of-the-best-28-on-the-basics/msg1299245/#msg1299245 (https://www.eevblog.com/forum/beginners/op-amp-youtube-videos-my-list-of-the-best-28-on-the-basics/msg1299245/#msg1299245)

Since this is a popular topic I am thinking of adding Transistor Checkers as a subject.

I could use some help. If you could pick from 5 fo 10 good videos (channels) on this subject, I will include them and be very grateful.

The addition of recommendations to the sheet is being worked on by Brumby.  It is not there yet.  I do have the Op Amp selection in a sheet in the latest version that you can download from here

https://www.eevblog.com/forum/other-blog-specific/dd/msg1299782/#msg1299782 (https://www.eevblog.com/forum/other-blog-specific/dd/msg1299782/#msg1299782)

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on September 13, 2017, 09:51:56 pm
@ez24, for a 114 year old male you are looking great. :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 13, 2017, 11:34:00 pm
that list is missing a couple of important entrys!
https://www.youtube.com/channel/UCQak2_fXZ_9yXI5vB_Kd54g/videos (https://www.youtube.com/channel/UCQak2_fXZ_9yXI5vB_Kd54g/videos)

https://www.youtube.com/user/educ8s/videos (https://www.youtube.com/user/educ8s/videos)
 8)

Title: Re: $20 LCR ESR Transistor checker project
Post by: ez24 on September 14, 2017, 12:44:23 am
that list is missing a couple of important entrys!

Thanks they will be in the next upload
Title: Re: $20 LCR ESR Transistor checker project
Post by: hpapagaj on September 15, 2017, 09:41:47 pm
Hello all,

I am looking to buy this type of tester, but I can't decide which one to buy.

This is the cheapest what I found, but it's without case:

https://www.aliexpress.com/item/2016-DIY-kits-ATMEAG328-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Frequency/32815242766.html (https://www.aliexpress.com/item/2016-DIY-kits-ATMEAG328-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Frequency/32815242766.html)

Second one is with case:

https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32785578867.html (https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32785578867.html)

Third says that it's the latest model (including DS18B20, DH11, IR decoder). It is true? Or the first two is the same?

There is one more version, with older 1.05 FW, but what I like in this is that it is sold wih probes:

https://www.aliexpress.com/item/M328-version-ESR-Tester-Meter-Transistor-Capacitance-Inductance-PNP-MOS-NPN-JFET-free-shipping/32745769814.html (https://www.aliexpress.com/item/M328-version-ESR-Tester-Meter-Transistor-Capacitance-Inductance-PNP-MOS-NPN-JFET-free-shipping/32745769814.html)

Can I use probes with the first 3 version? I am thinking in attaching probe wires directly into the "grill" connector (sorry I don't know the exact name) - I want to test in-circuit components too (I know that it's not ideal scenario).

All suggestions are welcomed.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 16, 2017, 10:44:30 am
AFAIK the clones with a fixed IR receiver module run a modified firmware supporting only two IR protocols. The m-firmware supports 10 IR protocols and a few variations of some protocols. And you can simply connect an IR receiver module to the three probe pins (a fixed module is supported too). I'd recommend to choose a clone which allows you to upgrade the firmware easily (DIP socket or ISP header).
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 16, 2017, 11:52:37 am
Wow, very nice job!  I recently got one of these delivered to me in non-working condition, now I may be able to figure out why.
Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 16, 2017, 04:01:53 pm
Is there a schematic example of the touch screen implementation floating around somewhere that I have not seen or noticed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 16, 2017, 04:43:14 pm
Adding some more info as I research the touch screen option. The controller is a ADS7843 12 bit ADC. Also note the part number XPT2046 is a functional equivalent.
Texas Instruments HTML page for ADS7843 (http://www.ti.com/product/ADS7843)
Direct link to TI PDF for ADS7843 (http://www.ti.com/lit/pdf/sbas090)

   I assume the touch screen controller circut is somewhat like the random schematics attached? I'm trying to understand how the test button and MCU Vcc control circuit work with the touch screen ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 16, 2017, 05:03:34 pm
Adding some more info as I research the touch screen option. The controller is a ADS7843 12 bit ADC. Also note the part number XPT2046 is a functional equivalent.

   I assume the touch screen controller circut is somewhat like the random schematics attached? I'm trying to understand how the test button and MCU Vcc control circuit work with the touch screen ;)

The ADS7843 simply shares the SPI with the display and needs two additional IO pins for /CS and /PEN_IRQ. The circuit isn't that interesting, because you can buy LCD modules with touchscreen and ADS7843 included. If the module doesn't got a pull-up resistor for /PEN_IRQ you should add an external one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 16, 2017, 05:16:58 pm
The ADS7843 simply shares the SPI with the display..
  So is it basically like using the rotary encoder option (+2 extra pins for the touch screen)?
 
Would you use this with a separate test button and the PNP/NPN MCU controlled power circuit or is this limited to a on/off power switch?

Can the touch screen option run in parallel to the rotary encoder?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 16, 2017, 05:59:28 pm
Yes, you still need the power/test push button for powering on and selecting the tester's mode. The touch screen UI provides a software test button which can be used in parallel after powering on the tester. And the touch screen can be used in parallel with a rotary encoder or increase/decrease push buttons. The m-firmware has a simple UI framework which maps different user input types to virtual keys.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 16, 2017, 08:02:06 pm
Thanks. That really helps me understand how the touch screen option fits in. I'm almost finished copying all 44 circuit options into a single KiCad schematic. I just need to figure out an easy way to show the circuit options hierarchy on one schematic document. I haven't figured out if it's better to use a giant flat schematic or the hierarchical layouts in KiCad to create a PDF to share with others. I've been working on different ways to show the options and flow... haven't found one I like yet.
  I'm also trying to figure out how to upload, maintain, and store files on GitHub. Then I can just upload a bunch of half finished junk and really confuse people  :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 17, 2017, 12:39:57 am
Hi,

I recently received an AY_AT tester which was supposedly fully assembled and fully working, been trying to get it successfully thru the Self-Test,  but the thing won't read anything connected to TP1 and TP3. 

After doing the S-T a number of times with the same result of timing out of the test with the display still flashing '0pF', I discovered that if I held the cap to either 1 and 2 or 2 and 3 it would immediately give the approximate value;  I finally accepted that it was not going to read anything when hooked to TP1 and 3.     

Thanks to those lovely interconnect images posted by jake in that utube video, I've found a definitive symptom so I'm hoping to narrow it down to what the actual failure could be.  According to the schematic TP's 1, 2 and 3 hook directly to pins 23, 24 and 25, respectively speaking, on the Atmel chip:  TP1 to pin 23 measures less than an ohm, TP2 to pin24 measures less than an ohm, but TP3 to pin 25 measures about 2.5 Megohms.

Thinking about a jumper wire now... any ideas as to what's going on, what went wrong with the connection?  I ended up going over any dull-looking solder joints (which was  just about all of them).  Since the Atmel is socketed I reseated that, made no difference.   I tried to measure a few caps and it seems to be at least in the ballpark, but no testing of 3 lead devices kinda sux.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on September 17, 2017, 01:02:15 am
Hi,

I recently received an AY_AT tester which was supposedly fully assembled and fully working, been trying to get it successfully thru the Self-Test,  but the thing won't read anything connected to TP1 and TP3. 

After doing the S-T a number of times with the same result of timing out of the test with the display still flashing '0pF', I discovered that if I held the cap to either 1 and 2 or 2 and 3 it would immediately give the approximate value;  I finally accepted that it was not going to read anything when hooked to TP1 and 3.     

Thanks to those lovely interconnect images posted by jake in that utube video, I've found a definitive symptom so I'm hoping to narrow it down to what the actual failure could be.  According to the schematic TP's 1, 2 and 3 hook directly to pins 23, 24 and 25, respectively speaking, on the Atmel chip:  TP1 to pin 23 measures less than an ohm, TP2 to pin24 measures less than an ohm, but TP3 to pin 25 measures about 2.5 Megohms.

Thinking about a jumper wire now... any ideas as to what's going on, what went wrong with the connection?  I ended up going over any dull-looking solder joints (which was  just about all of them).  Since the Atmel is socketed I reseated that, made no difference.   I tried to measure a few caps and it seems to be at least in the ballpark, but no testing of 3 lead devices kinda sux.
You have analysis paralysis. 
Just run the jumper wire and be done.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 17, 2017, 11:47:38 am
I was hoping that someone familiar with the board's construction might have an idea of where the actual problem lies, and whether it's likely to progress or not, just asking for 'informed guesses'  &-)

Also, this tester was purchased as a fully assembled and working  tester, and, what with shipping costs to China, I guess I'm stuck with it,
and at the cost  (it was 12 bucks plus 6 for shipping) not getting hurt too bad, but I feel I'm just being played by a vendor who has defective wares to sell.

So, buyer beware, picture attached:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 17, 2017, 12:28:13 pm
Could be a bad PCB. Someone had such a clone with a short between one probe pin and Vcc. He managed to locate the short between two traces.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 17, 2017, 01:01:11 pm
Could be a bad PCB. Someone had such a clone with a short between one probe pin and Vcc. He managed to locate the short between two traces.

I've been telling the vendor I suspect the circuit board, I've sent her pictures, and she wants more pictures, doesn't understand what I write - I suppose it's possible it worked when it was shipped, but I think that's too much of a coincidence for me to accept.

So, I guess I'll add a jumper from the 'chip-clip' to pin 25 of the Atmel chip and see if that fixes it.

Thanks for you help, and for being so free with your knowledge.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 17, 2017, 01:41:58 pm
some AY-AT kits got shipped with blank microcontrollers.
you would know that if you searched this thread.  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 17, 2017, 02:12:51 pm
stj:  "some AY-AT kits got shipped with blank microcontrollers.
you would know that if you searched this thread."

Oops  8-).

I' m thinking I'm gonna try to leverage a spare Atmel chip for my troubles ; -).

Say stj, I think I read that the firmware is up to 1.28 now, this tester has 1.12 installed, any thoughts on wether to leave well enough alone, or do you think I should upgrade?  If so, any particular version?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 17, 2017, 03:42:14 pm
There are two firmware versions:
- k-firmware: 1.13k
- m-firmware: 1.29m
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 17, 2017, 03:52:32 pm
madires:  "There are two firmware versions:
- k-firmware: 1.13k
- m-firmware: 1.29m      "


Oh, okay, I see I need to read up on the firmwares - I've got the K version, so not really behind by much. 

This little tester is just so amazing, it'll be weeks before I know how to operate it...thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 17, 2017, 08:09:18 pm
Back again, another question about the AY-AT tester :  would it be possible for one of the the ADC inputs to be blown and the tester still work somewhat normal with the 2 remaining ADC inputs? 

Reason I ask is that when I went to put the missing connection to TP3 in it was no longer needed (there's less than an ohm between TP3 and pin 25 of the Atmel),  Something is still screwy with this thing and it still won't measure anything on TP1 to TP3 during the self-test, hopefully a new Atmel chip will straighten it out.  very hopefully.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on September 17, 2017, 09:01:59 pm
Back again, another question about the AY-AT tester :  would it be possible for one of the the ADC inputs to be blown and the tester still work somewhat normal with the 2 remaining ADC inputs? 

Reason I ask is that when I went to put the missing connection to TP3 in it was no longer needed (there's less than an ohm between TP3 and pin 25 of the Atmel),  Something is still screwy with this thing and it still won't measure anything on TP1 to TP3 during the self-test, hopefully a new Atmel chip will straighten it out.  very hopefully.
You may have just a simple bad pin soldering on 328 pin.if you can resolder the 3 acquisition pins.regards,Pierre


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 18, 2017, 02:32:35 am
I'm looking for a AY_AT off ebay and preferably from a north american seller. but i've read where some are using components that are two high tolerance. can anyone tell me known good sellers?
assembled or kit is fine with me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 18, 2017, 11:42:02 am

You may have just a simple bad pin soldering on 328 pin.if you can resolder the 3 acquisition pins.regards,Pierre

Envoyé de mon iPad en utilisant Tapatalk

Thanks for the suggestion - I've now touched up all the solder joints on the bottom of the board. 

 This did result in a bit of an improvement as during the self test the 3 pF values AY-AT computes went from "42pF,46pF,12pF" to a more normal looking"44pF,46pF,43pF" - I have no idea what it means or how this affects it's calibration  8-{

The top of the board also has crappy looking solder where ever there's a through hole but my hands are a bit too shaky to attempt them (yet).

Seems odd to me but it seems to be capable of reading transistors, both fets and bjts, wish I had some known quantities I could try.  It does seem fairly accurate on capacitors, but still won't complete a self-test (unless I cheat).
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 18, 2017, 06:13:39 pm
All I have to say is - have you ever ordered cheap solder from the $0.99 sellers that offer these clones? In my opinion, it's not solder. It's string with shinny makeup applied. I assume this is what they use to put together the clone boards. By the looks of most of the kit soldering jobs I've seen, I believe they have some kind of drinking game that involves hanging upside down while soldering behind one's back. I would not trust a single spot.

  The AY-AT PCB has some really nice plated through-holes. Several have traces on both sides. I'd break out the flux pin and good solder for this kind of thing, especially for that ZIF socket that is guaranteed to receive a lot of mechanical stress.

  The AY-AT has been covered extensively here since page 83. The last 10 pages of this thread are mandatory reading on the subject. Several people have summarized problems and consolidated information. If you want even more references (https://www.youtube.com/playlist?list=PLPIwHuVy9EyMXIBZ7wwlBu1o0PXTrpG_s) look through my images index 3 of 3. This will guide you to every time someone referenced the AY-AT with pictures. These include lithium batteries, Q charging, enclosures, unprogrammed chips, short circuit, bad capacitor, capacitor mods, programming options, schematics, etc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 18, 2017, 10:24:51 pm
Hi Jake, and thanks for the links and info on the AY-AT, especially any info on how and where the board's vias and 'invisible' interconnections might be located? lol, I guess that's asking a bit too much.  I'm still reading this thread, up to 3700-somethingth
post so far, so maybe I'll get there...

This is my third tester, the first 2 I bought as DIY kits and had no trouble at all doing a self-test as soon as I turned them on.  The 1st one has the atmega168a-pu chip and is also socketed, which I think is a nice feature, since I can't imagine me replacing one of those smd atmega328's, which is what the 2nd kit I bought has in it. 

So, now I'm kinda wishing I'd just got another kit rather than get this one that pretty much needs a complete soldering redo, I'd have had it finished days ago now, rather than be still bickering with some clown 12K miles away who assumes (rightly) that there's nothing I can do about their crappy service/product.

There, I feel better now, sorry bout that. 

Anyway, as far as soldering and resoldering goes, I had mixed success  with the second tester - after using it for many moons, mainly checking capacitors, it got to where only 2 of the leads could be used (it would say "unknown or damaged part" if you tried using it), so I resoldered the chipholder, treating all pins w/good dose from a flux-pen, and It did go back to  normal for a few uses, but then after a few days started flaking out again;  so I resoldered again, with a little higher temp and when I was through the damn thing didn't work at all any more.   It seemed to me that maybe some connections inside the ckt bd. that need to wick in some solder for some reason don't wick in enough and some corrosion process starts up - I wonder if they get exposed to salt air at any time in their life.

Thanks for the ideas and the links, not to mention all the work that you put into assembling it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on September 18, 2017, 10:55:02 pm
Hi Mike, welcome to the forum...
   do you mind take couple of pictures of your AY-AT board? Solder and component side closeup...
Also some pictures during self test could help to identify if there is some value completely off.
Instead of resolder everything, have you tryed to clean the board with isopropyl alcohol?
Ciao
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 18, 2017, 11:44:44 pm
I will not keep making changes... I will not keep making changes...I will not keep making changes... :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 19, 2017, 02:03:34 pm
Hi Mauro,thanks!
   
You said:  "do you mind take couple of pictures of your AY-AT board?..."

 Well, I wouldn't mind at all, but my SD Card reader quit working yesterday, so it may be a little while before I find an alternative.  How about a comparison of the stored data  ?

   Under 'show data' mine says:
R0  .51 .45 .47
Rint hi =22
Rint lo =19.9
C0  has 2 entries:  42,43,46 and 44 44 46
Ref C -5
Ref R -27
You also wrote:

 "...Solder and component side closeup...
Also some pictures during self test could help to identify if there is some value completely off.
Instead of resolder everything, have you tryed to clean the board with isopropyl alcohol?"

The board looks/is real clean, no residue of anything that can be seen, it's just the solder was all dull silvery-gray looking (either it's lead-free or they are all cold joints, or both), now it's only like that on the top. 

I guess I really need to do a video, but not up to speed on how to use youtube, maybe in a few days...but, simply put, It continually blinks '0pF' if you hold the cap leads to either the pads or if you clamp it in to the chip-clip's 1 and 3...damn, just went to check something and It finally completed self-test, Yay!  That seems to have changed the Ref values a bit, it's now -3 for C and -24 for R.

Regards,
Mike
Title: Re: $20 LCR ESR Transistor checker project
Post by: tablatronix on September 19, 2017, 07:06:33 pm
If you have one terminal that refuses to work ,could it not be the TVS , sorry if it was mentioned yet, but tvs or micro pin seem the most obvious points of failure.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 19, 2017, 07:48:03 pm
I'm not familiar how a TVS protection ckt. works. 

No matter though because I think I've determined the actual problem - the pads are mis-numbered on the ckt. bd., The top pad is marked 3 and the outer lower pad is marked 2, if I switch the numbers it works right. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: tablatronix on September 19, 2017, 08:58:38 pm
ah you are right, the smd pads are 2-3 swapped
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 20, 2017, 04:18:20 pm
what is the appropriate replacement for the TL431A thats .1 % for the AY-AT?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2017, 04:40:56 pm
LM4040 for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 20, 2017, 04:55:31 pm
sot-23?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2017, 05:02:34 pm
TO-92 and SOT-23 (check the datasheets for the pinout).
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on September 20, 2017, 05:04:52 pm
For example:
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 20, 2017, 05:23:57 pm
THANKS!
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 21, 2017, 08:46:25 pm
the kit came before the better tolerance parts .. but .. I can't resist building it ... no self control what can i say.
heck the better tolerance parts and the spare atmega cost as much shipped as the kit.. shesh.

Shiny red button syndrome
(http://the7gracesofmarketing.com/wordpress/wp-content/uploads/2013/11/Stimpy-presses-shiny-red-button-animated.gif)
https://vimeo.com/126720159 (https://vimeo.com/126720159)


Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on September 22, 2017, 07:41:12 am
Hi madires,
     I think I lost the results of the beta testing of the new ESR function...
Do you need more beta tests from us?
Ciao
   Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 22, 2017, 09:02:39 am
So far you're the only one testing the modified ESR measurement. It would be nice if a few more could check it out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on September 22, 2017, 09:21:31 am
I think indman is the only one you are referring to and the only one that reported some results here
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1284997/#msg1284997 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1284997/#msg1284997)
I only compiled and normaly used during some repair.
What you expect to receive as useful feedback?
- ESR displayed for low caps?
- comparison with the old m or k firmware with the same components?
- more accurate and or precision measurements?
If you want I can try something specific on my unit.
Mauro

Title: Re: $20 LCR ESR Transistor checker project
Post by: BradC on September 22, 2017, 11:00:58 am
So far you're the only one testing the modified ESR measurement. It would be nice if a few more could check it out.

I have plenty of caps but only a Bob Parker ESR meter to compare against. Is that any use?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 22, 2017, 12:56:07 pm
Yes, of course. Sorry indman! The ESR measurements of a few caps like 10nF, 47nF, 100nF, 220nF, 470nF, 10µF, 100µF and 1000µF with the m-firmware including the ESR mod and some other ESR meter would be helpful. And the test frequency of the other ESR meter (select 1kHz if supported).

BTW, I'm working on a PCB for the enhanced frequency counter hardware option at the moment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 22, 2017, 09:09:45 pm
So far you're the only one testing the modified ESR measurement. It would be nice if a few more could check it out.

soon as my parts arrive, id be willing to check it out as i will ahve a spare atmega to load

i've got a nice de-5000 to compare it against. jsut need to figure out how to load an atmega lol.  been a while since i've played with them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeL on September 22, 2017, 10:59:20 pm
Here's a pic of the finished AY-AT tester.  This is one on which the SMT-test pads are mis-labelled, the one marked 3 is 2 and vice versa - I guess this may be why the instructions I got say to only use the chip-holder when doing the self-test.  Seems some of the boards have been made with correctly labelled, incorrectly labelled, and unlabelled SMT Test pads, still going through the thread...
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 24, 2017, 01:46:46 am
 Must feed the Wumbus ;)

    This is a comparison of all of the display options sans the Nokia 1100 (PCF8814). I could not find visual area measurements on it. Most of the measurement and range data is from buydisplay.com. This list is subject to errors as I have not double or triple checked my work. I made this casually just to have a basic idea of how each display compares in size. I collected a good bit more data including the part numbers referenced, the "compatible IC's" and interface options for almost all of these. That probably needs to go on a spreadsheet instead of directly here.
The basic visual area numbers are as follows:
16×2 XL
VA 99×24mm
20×4
VA 76×25mm
ST7920 2.9"
VA 72×40mm
ILI9341 3.1"
VA 49×65mm
ST7565 2.6"
VA 65×37mm
16×2
VA 65×15mm
NT7108 2.9"
VA 62×44mm
16×4
VA 62×25mm
ILI9341 2.2"
VA 39×55mm
ILI9342 2.3"
VA 47×35mm
12×2
VA 46×14.5mm
ST7565 1.4"
VA 36x20mm
SSD1306 1.3"
VA 31×17mm
SSD1306 0.96"
VA 24×13mm
SSD1306 0.49"
13×7mm (untested)
ST7036
VA 51×15mm
ST7735
VA 38×32mm
PCD8544
VA 36×26mm
PCF8812
VA 22×30mm
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 24, 2017, 03:51:05 am
@madires
got my ISP running and received my spare atmega so,I'm happy to help out testing beta ESR code if you like.
just need to know where the beta code is.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 24, 2017, 04:02:58 am
@madires
got my ISP running and received my spare atmega so,I'm happy to help out testing beta ESR code if you like.
just need to know where the beta code is.  :-+
Original Post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1282688/#msg1282688)
The File (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1283383/#msg1283383)
The last reply (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1284997/#msg1284997) (I think)
 :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 25, 2017, 11:19:02 pm
got the precision resistors and voltage reference installed now
working out all the right config settings / fuses still for the m version of the firmware on my AY-AT.
so far just getting a white screen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 26, 2017, 08:49:10 am
The settings for the AY-AT are listed in the "Clones" file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on September 26, 2017, 10:25:44 am
Hi Markus,
    I made a quick test on few capacitors to test the beta and found strange results.
Referring to the attached picture, in the upper part you can find the measurement of the ESR made with the k firmware, in the lower part, the beta m.
I think this are similar results to the one indman reported.
The current 1.29m is not detecting the ESR of any of this capacitors but the 220n one that it is detectes a 0.7ohm, up to 1.5ohm (multiple measurements)
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 26, 2017, 02:07:25 pm
Thanks! The ESR measurement in 1.29m is only performed if the capacitance is larger than 180nF (beta: >= 10nF). Low values like 220nF may vary with the old ESR measurement method. The huge difference for low value caps between k-firmware and the beta m-firmware is interesting. While working on the beta I've cross-checked the results with a proper LCR meter (1kHz) and the ESR values matched reasonable in most cases. Let's wait for more beta results, maybe in comparison with a professional LCR meter (1kHz test frequency).
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 26, 2017, 11:04:23 pm
@madires

got it

here are the measurements using your code in 1.29m
DE-5000 set to 1khz
ESR in ohms

de-5000 218.1nf    10.46 ohms
tester  224.7nf     3.20 ohms

de-5000 922.8nf     1.18 ohms
tester  944.9nf     0.85 ohms

de-5000 10.223nf   55.51 ohms
tester  10.29nf   107.50 ohms

de-5000 152.45uf    3.22 ohms (known bad electrolytic)
tester  191.4uf     2.66 ohms IL 2.48ua

de-5000 976.0nf     0.12 ohms (very high quality cap)
tester  984.1nf     0.78 ohms

Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 27, 2017, 02:38:36 am
I've bought one of the M328 variants and I think I might have buggered it. Here's the link to the model I got.
http://www.ebay.com.my/itm/142372146504 (http://www.ebay.com.my/itm/142372146504)

When I first turn it on, it went through the self test sequence. After its done, it shows the Menu screen then changes to show battery ok and then Vext=0 flashing.
I googled and found this thread, someone got it too but he rectified it. Another poster mentioned it could be a cold solder joint.
I went back and reflowed everything and it works again for a while. Then it goes to the flashing Vext=0 again.
Reflowing again makes it work again, but after the components cooled off it flashes Vext=0 again.
At one point it worked long enough that I managed to put together the case, and then it refused to work again.

What could it possibly be?
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 27, 2017, 03:16:16 am
does the led come on?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 27, 2017, 04:10:55 am
that's an AY-AT,
v-ext may mean the reference - check the connections to the TL431
Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 27, 2017, 06:00:54 am
does the led come on?
Yes the LED comes on. Thankfully I don't have the problem with the LED like some others that need to press and hold the encoder to keep it on.

that's an AY-AT,
v-ext may mean the reference - check the connections to the TL431
I do have an extra TL431 for cases like this. Thanks a lot!
Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 27, 2017, 12:46:14 pm
Rechecked the connections to and from the TL431, replaced the TL431 as well. Still wouldn't work.
I reflowed again several times and it did work again once for several minutes. Tried reflowing a few more times but it wouldn't work.
At wits ends now. Buying is cheap but I'm gonna have to wait for another 3 weeks of shipping.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 27, 2017, 06:24:34 pm
bad chip socket contact?
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on September 27, 2017, 09:12:48 pm
I've bought one of the M328 variants and I think I might have buggered it. Here's the link to the model I got.
http://www.ebay.com.my/itm/142372146504 (http://www.ebay.com.my/itm/142372146504)

When I first turn it on, it went through the self test sequence. After its done, it shows the Menu screen then changes to show battery ok and then Vext=0 flashing.
I googled and found this thread, someone got it too but he rectified it. Another poster mentioned it could be a cold solder joint.
I went back and reflowed everything and it works again for a while. Then it goes to the flashing Vext=0 again.
Reflowing again makes it work again, but after the components cooled off it flashes Vext=0 again.
At one point it worked long enough that I managed to put together the case, and then it refused to work again.

What could it possibly be?

I had the same problem and was open the 27K resistor that goes between collector of transistor S9014 and pin7 of Mega 328
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on September 28, 2017, 04:36:28 am
So first peak at my incomplete rough draft of all LCD options. I'm trying to go between KH's PDF, Markus's readme and controller datasheets to create this. I am worried I may be making some dumb fundamental errors with topology. Hopefully someone can help me catch them early.
    This is the first time I've plotted the file and it has some odd text sizing issues with the way I labeled stuff with text. I'm not worried about that. I'm mostly interested in the basic stuff like how I set up the buffer/pull up resistors. If anyone can just have a quick glance I'd appreciate it ;)
Feel free to PM me as well if that's more appropriate,... doesn't matter to me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 28, 2017, 06:08:23 am
bad chip socket contact?
What's a safe way to test it? Would it be ok if I stick continuity probes to the chip leg in top and the solder point at the bottom?

I had the same problem and was open the 27K resistor that goes between collector of transistor S9014 and pin7 of Mega 328
Thank you very much, I'll try and see if that could be the case too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 28, 2017, 06:24:40 am
no problem with checking continuity with a meter, the chip is 5v tolerant and i'v never seen a meter use more than 3.5v
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on September 28, 2017, 07:32:10 am
bad chip socket contact?
What's a safe way to test it? Would it be ok if I stick continuity probes to the chip leg in top and the solder point at the bottom?

yes and no.you have to do somme shitty work like test with ohmeter endpoint to endpoint ALL traces and EVERY trace with his neighbor
hoping you find this way some imperfection on pcb trace (uncoroded copper);but this will not always work (you tension the board a little,the
unwanted remaining copper may do or not do an unwanted electrical contact between 2 separated traces.
Solution:microscope or magnifier, like an detective.there are posts here telling bad experiences like that,happens all the time with easy-peasy board
manufacturers with zero testing board procedure (hope you got it,you may have uncoroded copper remaining between different traces/nodes)

I had the same problem and was open the 27K resistor that goes between collector of transistor S9014 and pin7 of Mega 328
Thank you very much, I'll try and see if that could be the case too.
[/quote]
more rare but can happen very easy/quick to see with your ohmeter
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on September 28, 2017, 07:52:02 am
If the tester works fine for a bit and than stops, I don't think it is a permanent damage like a short or an open component/trace.
How are you powering the board? I have to go back to your posts, but are you using a fresh 9V battery or a power supply?
Have you measured the 5V across the Atmega power pins (pushing the button) when it is not working?

I know I'm boring and I ask this every time, but can you provide pictures of the board with and without the display? (component side and bottom side)
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 28, 2017, 11:38:03 am
I'm using a new battery and tested the pin 7-22, there is 5V on the board. I've tried checking the 27k resistors too with same voltage.

Emailed the seller and he asked his engineer. The engineer said it could be faulty 9014 transistors. Here's my board photos. The capacitors look different because I ordered them from Element14.

 (http://)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on September 28, 2017, 02:03:33 pm
Ok, remove all transistors and check it with your transistor tester.... >:D
If you can, check the placement of the transistors and replace it one by one verifying if something changes.
Do the same with the 2 electrolitic capacitors, I can't tell the polatity from the picture..

Quote
The capacitors look different because I ordered them from Element14

?? Why, there was something missing in your kit? It was a preassembled board?
As quick test, remove the SVR5-04 ad D3 (P6KE...) if nothing changes, when you will fix the unit you can place it back.

Wait for the tester to fail and measure the voltage on this pins of the microcontroller:
13 = 5V if the tester is on
12 = 5V if the tester is on

How is Ubat when the tester fails? (refer to the schematic, i mean Vbat after T1)

Mauro

Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 29, 2017, 12:01:09 am
Ok, remove all transistors and check it with your transistor tester.... >:D
*ba dum tishhh*
Oh you..

If you can, check the placement of the transistors and replace it one by one verifying if something changes.
Do the same with the 2 electrolitic capacitors, I can't tell the polatity from the picture..

?? Why, there was something missing in your kit? It was a preassembled board?
As quick test, remove the SVR5-04 ad D3 (P6KE...) if nothing changes, when you will fix the unit you can place it back.

Wait for the tester to fail and measure the voltage on this pins of the microcontroller:
13 = 5V if the tester is on
12 = 5V if the tester is on

How is Ubat when the tester fails? (refer to the schematic, i mean Vbat after T1)

Mauro
The capacitor polarity is correct, I've referred to the silkscreen.

I ordered some of the components separate from E14 because from past experiences I've received some dubious components (mainly amplifier and PSU kits), and this being a reference tester I figured I should confirm myself with original components from a trusted shop. I bought; all ceramic and electrolytic capacitors, HT7550, and TL431. 9012 and 9014 aren't available at the time. I didn't get resistors because they're always within 1-5%.
The problem had started the first time I turned it on, so thinking it was the transistors I bought being a different spec, I swapped them out with the ones that came with the kit.

Is this what you meant with SVR5-04 ad D3?
(http://images.mcmanager.co.uk/images/1389957170762.jpg)

And testing the 12 and 13 pins with reference to ground?
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 29, 2017, 01:21:18 am
LOL ... gotta love it.

when we all know its cheaper just to buy another one .,.. but. you cant just let it go
that is what makes EEVBLOG forum great!

never say die!

Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 29, 2017, 01:51:47 am
Imagine replacing everything onboard only to realize the firmware in the atmega was corrupted. :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 29, 2017, 01:53:33 am
well they have been sold with BLANK chips before!!
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: innkeeper on September 29, 2017, 03:29:10 am
that thought had crossed my mind, corrupt firmware, but, it seems he says works for a bit at times after he re flows, like its aggravated with heat.
still could be a bad at mega .. worth swapping out.

ya know eventually this is going to become like Abe Lincolns ax, all original, but the handle and the ax head have been replaced.
Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 29, 2017, 10:57:22 am
1) As quick test, remove the SVR5-04 ad D3 (P6KE...) if nothing changes, when you will fix the unit you can place it back.
Wait for the tester to fail and measure the voltage on this pins of the microcontroller:
2) 13 = 5V if the tester is on
3) 12 = 5V if the tester is on
4) How is Ubat when the tester fails? (refer to the schematic, i mean Vbat after T1)
1) I did not do this yet, I ran out of solder wick to desolder it.
2) Pin 13 to ground is 5V
3) Pin 12 to ground is 0.63V
4) Vbat to ground is 8.7V
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 29, 2017, 12:32:00 pm
Pin 12 (PD6) drives a NPN transistor which keeps the tester alive. The voltage of 0.6V looks suspiciously like the NPN's V_BE.
Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 29, 2017, 02:33:23 pm
1) As quick test, remove the SVR5-04 ad D3 (P6KE...) if nothing changes, when you will fix the unit you can place it back.
Wait for the tester to fail and measure the voltage on this pins of the microcontroller:
2) 13 = 5V if the tester is on
3) 12 = 5V if the tester is on
4) How is Ubat when the tester fails? (refer to the schematic, i mean Vbat after T1)
1) I did not do this yet, I ran out of solder wick to desolder it.
2) Pin 13 to ground is 5V
3) Pin 12 to ground is 0.63V

[/b]4) Vbat to ground is 8.7V
Pin 12 (PD6) drives a NPN transistor which keeps the tester alive. The voltage of 0.6V looks suspiciously like the NPN's V_BE.
I'm very sorry, the 12 and 13 are reversed.
Pin 12 is 5V
Pin 13 is 0.67V
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 29, 2017, 05:01:06 pm
Have you measured the voltage at pin 13 while pressing the rotary encoder?
Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 29, 2017, 05:50:08 pm
Have you measured the voltage at pin 13 while pressing the rotary encoder?
When pressing the encoder, pin 13 has 7.1mV.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 29, 2017, 07:27:58 pm
Pin 13 should have 5V when the tester is running and the rotary encoder isn't pressed. When pressed the voltage should be V_CE of the driver transistor. If my circuit diagram is correct it's T2 (or Q2). Since the power/test push button is low active the firmware thinks the rotary encoder's push button is pressed all the time, because 0.67V is much too low for a logic high level. I'd check the parts between the rotary encoder's push button and pin 13.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on September 30, 2017, 01:50:12 am
 Just found this and ordered one from Taobao.  Looks like an interesting variant, by Mastech this time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 30, 2017, 03:42:16 am
Kind of a cool enclosure. Bummer there's no rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on September 30, 2017, 04:29:15 am
interesting, it has a discharge resistor on the left, 2 buttons??
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on September 30, 2017, 07:28:36 am
interesting, it has a discharge resistor on the left, 2 buttons??
Guess so, 1k resistor, slots fot capacitor to be put in for 2 sec to discharge.

If possible, I am thinking to put in an encoder later but the interations on taobao are much faster than mine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 30, 2017, 09:21:01 am
If possible, I am thinking to put in an encoder later but the interations on taobao are much faster than mine.

And please don't forget to take some pictures of the PCB ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on September 30, 2017, 11:23:15 am
Pin 13 should have 5V when the tester is running and the rotary encoder isn't pressed. When pressed the voltage should be V_CE of the driver transistor. If my circuit diagram is correct it's T2 (or Q2). Since the power/test push button is low active the firmware thinks the rotary encoder's push button is pressed all the time, because 0.67V is much too low for a logic high level. I'd check the parts between the rotary encoder's push button and pin 13.
I went to my local electronics shop and got myself two 9014 and a 9012. Replaced them and it works somewhat.
When there's no components plugged in, it kept showing there's a capacitor something in the range of 300uf-400mf. sometimes it'll work well and shows no or faulty component.
I kept buggering with it some more and doing the self test a few times and it works ok now.

But for some reason the rotary encoder doesn't work anymore. It works as a pushbutton now. To navigate the menu you click once to move next, press and hold to select, and press and hold to exit the selection.
Also I think I buggered one of the transistors now because with the battery plugged in, the LED and screen lits up without pressing the encoder.

I'm like the opposite of having the Midas touch.

I bought a latching button and just turn it off when the battery is plugged in. It turns on whenever its plugged in now.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on September 30, 2017, 12:34:13 pm
If possible, I am thinking to put in an encoder later but the interations on taobao are much faster than mine.

And please don't forget to take some pictures of the PCB ;)

Yes, shall do so when it arrives.  For the time being, more screenshots:
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on September 30, 2017, 09:35:25 pm
If possible, I am thinking to put in an encoder later but the interations on taobao are much faster than mine.

And please don't forget to take some pictures of the PCB ;)

Yes, shall do so when it arrives.  For the time being, more screenshots:
How much do you payed?
Regards Pierre

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on October 01, 2017, 06:46:13 am
About 21 euro, plus another or two euro to ship to Singapore.
But the order is stuck for at least 10 days because of China National Day(according to seller).  Mastech canceled my other order of a new LCR tweezer.  Got a feeling they are using Taobao to test demand, and also selling well ahead of their production.  The LCR tweezer has been 2 months , nd still on pre-order status.  But at least they did not reject my order this time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on October 01, 2017, 08:01:16 am
About 21 euro, plus another or two euro to ship to Singapore.
But the order is stuck for at least 10 days because of China National Day(according to seller).  Mastech canceled my other order of a new LCR tweezer.  Got a feeling they are using Taobao to test demand, and also selling well ahead of their production.  The LCR tweezer has been 2 months , nd still on pre-order status.  But at least they did not reject my order this time.
Thanks. It's really possible that they test before.
Anyway the case look good. For me it's one of the best variants.
Regards Pierre

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on October 01, 2017, 06:25:45 pm
I just finished the LCD master project schematic. Let me know if you find any errors or other stuff I should note before sending it off to KH.

...and here is a link to my latest AY-AT schematic (https://drive.google.com/file/d/0B83qZTwOZWHGSWdzdVRKWmV4eUU/view?usp=sharing) (J1.3) in PDF form linked through one of my google drive accounts because it's 1.5mb due to the pictures of the PCB that are included in the PDF. It's over the 1mb limit so I can't upload it directly here. ...Still gots to figure out that whole github nonesense.
-Jake
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 02, 2017, 07:22:42 am
I just finished the LCD master project schematic. Let me know if you find any errors or other stuff I should note before sending it off to KH.
Thanks,jakeisprobably!
I would like to specify some nominals of elements on the diagram:
R8-33k (in the original 27k)
C2-100nF (in the original 10nF)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on October 02, 2017, 08:50:04 am
But for some reason the rotary encoder doesn't work anymore. It works as a pushbutton now. To navigate the menu you click once to move next, press and hold to select, and press and hold to exit the selection.
Also I think I buggered one of the transistors now because with the battery plugged in, the LED and screen lits up without pressing the encoder.

I'm like the opposite of having the Midas touch.

I bought a latching button and just turn it off when the battery is plugged in. It turns on whenever its plugged in now.

Hi penmarker, I think you are really close to solve all the issues!!
Most probably the culprit is one of the transistors in the power section.
Since the tester is responding to the push button of the encoder, T2 should be fine.
Try to remove T1 and T3 verifying that T1 is really a PNP and T3 is NPN.
Verify also that base, emitter and collector are correctly oriented (refer to the schematic and ignor silkscreen) since similar transistor can have different pinout (base not in the middle).

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: penmarker on October 02, 2017, 10:17:01 am
But for some reason the rotary encoder doesn't work anymore. It works as a pushbutton now. To navigate the menu you click once to move next, press and hold to select, and press and hold to exit the selection.
Also I think I buggered one of the transistors now because with the battery plugged in, the LED and screen lits up without pressing the encoder.

I'm like the opposite of having the Midas touch.

I bought a latching button and just turn it off when the battery is plugged in. It turns on whenever its plugged in now.

Hi penmarker, I think you are really close to solve all the issues!!
Most probably the culprit is one of the transistors in the power section.
Since the tester is responding to the push button of the encoder, T2 should be fine.
Try to remove T1 and T3 verifying that T1 is really a PNP and T3 is NPN.
Verify also that base, emitter and collector are correctly oriented (refer to the schematic and ignor silkscreen) since similar transistor can have different pinout (base not in the middle).

Mauro
Thank you very much for everything, you've been a very big help.
I'm still at work now so I can't test anything yet but I'll be leaving in a bit so I'll edit this post again later.

I can confirm T3 = T2 because I replaced both with new transistors.
I don't think I can remove to test either transistors because I've soldered them flush to the board and it makes desoldering hard. When I replaced them out I had to destroy the originally installed ones.

There's also the possibility of the transistors I replaced recently are shoddy quality because the shops there gets their supplies from China. I've attempted to buy some Sanken 2SA2922 from the same shop before but when I asked if they were genuine the clerk said no. I bought them from Digikey instead.

One question, could faulty transistors (T1/2/3) cause the rotary encoder to behave like pushbutton? My gut feeling says the atmega chip got reformatted or the firmware is now working as a push button model mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on October 02, 2017, 12:27:02 pm
If you had trouble replacing the transistors it could be possible that you have damaged the PCB near the transistors legs...
Try to make a single blob of solder on the 3 pins of the transistors and pull them out gently.
Verify the continuity of the traces near the pads on bouth sides.
If you remove T1 and replace it with a short between emitter and collector the tester shold power on immediately after applying power and you should be able to test T1 with the tester (now I'm not kidding...)

I don't have the tester with me so I don't know if I short emitter and collector of T1, also my encoder will be disabled... I'll try it later, or someone that knows the firmware better than me can cofirm if this make sense.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 02, 2017, 05:42:11 pm
Just the rotary encoder's push button is part of the power circuitry. A & B got pull-up resistors and are connected via additional resistors to the MCU in parallel with the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on October 02, 2017, 07:11:05 pm
Yes, but I was wondering if for some reason the firmware were disabling the encoder functionality because it was starting with PD7 (Pin13) low instead of high or something like that.
If T2 is fine I don't know how Pin13 can be low without pressing the push button, perhaps something wrong with T2 orientation...

Edit: or that was before replacing T2

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 02, 2017, 08:10:56 pm
No, the rotary encoder won't be disabled. But the read function checks for valid Gray code steps. If there's something wrong with the encoder the bad input will be ignored and nothing happens.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on October 03, 2017, 04:04:34 pm
...for some reason the rotary encoder doesn't work anymore....
Let's have some fun Mr Penmarker... (http://upcycleelectronics.blogspot.com/2017/10/pinmarker-troubles.html?m=1)
Those AY-AT diagnostic tools are from the creation of this:https://youtu.be/mRMRtrzh6rI (https://youtu.be/mRMRtrzh6rI)
   I'm no expert but it sounds like you have a bad connection somewhere.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on October 03, 2017, 11:04:06 pm
the last few days homework.... I think I got the 2 buttons option figured out. I wasn't able to find an example related to this project but I used another schematic I found. It looks like it's just the rotary encoder replaced with 2 buttons, if I set it up correctly. I also tried to adapt the MC34063 circuit from Nick's schematic. His is set up for a lithium battery and it doesn't have the same regulator isolation so there may be some errors there as well.

  I've also been looking into either building an adaptor for an ATmega1284 to 328 pinout or trying to design a board like this (http://www.firebirduino.com/sb_bb_v3/). It's an arduino clone/mod, but that's exactly what I had in mind for this project. I am surprised no one has built a design like this that can fit either an ATmega328 or ATmega1284 on the same footprint and breakout the extra pins. It seems like a no brainer for cheap clone manufacturers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 15, 2017, 05:13:39 pm
Just wanted to share a picture of the extended frequency counter option from Karl-Heinz' documentation (ATmega 644 circuit). The SMD transistors are hidden at the bottom side and there's a 32.768kHz watch crystal in the socket for the LF oscillator. The other one is a 20MHz crystal (measures 20.000960MHz). The channel can be changed by pressing the test button or turning the rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: turbochris on October 15, 2017, 11:48:42 pm
Hi All,
I bought an new style AY-AT tester kit off ebay that was advertised as the latest version. When I got it, there were 2 pcb-

(http://img.photobucket.com/albums/v185/serpent99/2pcb_zpswaodyw54.jpg) (http://smg.photobucket.com/user/serpent99/media/2pcb_zpswaodyw54.jpg.html)

I think when they made up these kits they just threw a new PCB in the old kits as the power jack, the 3 screw terminals and some resistors were missing.
I built it and the LED and display backlight come on when I press the encoder down and stay on for about 30 seconds but there is nothing displayed. I'm willing to bet that the ATMEGA328P-PU is programmed for the display used in the older kit. I'm not sure but I think my display is the ST7735. I found newer firmware here and I wanted to try it so I added an ISP header to the tester-

(http://img.photobucket.com/albums/v185/serpent99/20171015_191344_zpszubmwbxz.jpg) (http://smg.photobucket.com/user/serpent99/media/20171015_191344_zpszubmwbxz.jpg.html)

and hooked it up to an arduino to use the arduino as an ISP programmer-

(http://img.photobucket.com/albums/v185/serpent99/isp_zpsyk5qkdyt.jpg) (http://smg.photobucket.com/user/serpent99/media/isp_zpsyk5qkdyt.jpg.html)

(http://img.photobucket.com/albums/v185/serpent99/20171015_192258_zpsovhowawp.jpg) (http://smg.photobucket.com/user/serpent99/media/20171015_192258_zpsovhowawp.jpg.html)

I loaded the arduinoISP sketch into the arduino and this is as far as I got. I can't figure out the command line string for avrdude to use the arduino and I'm not sure where I need to put the .hex and .eep files I downloaded. Please help!
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on October 16, 2017, 08:46:58 am
Generally speaking do not use the firmware found on the thread. Usually they are customized for a specific reason like 16MHz crystal or with specific functions enabled.

To start, use the official one.
This is the repository for your variant:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/)

This is the avrdude string I use with ArduinoISP sketch

avrdude -c arduino -p m328p -B 0.5 -e -P COM5 -b 19200 -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

You will need to change the COM port number and (if this works...), to speed up the process you will change the BAUDRATE to 115200 on the sketch and on the string.

Let us know if you have any issue
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on October 16, 2017, 03:54:12 pm
If anyone wants to know more about the GPSDO Ublox modules/problems with the circuit design from Scullcom Hobby Electronics read this. (https://www.febo.com/pipermail/time-nuts/2015-April/091541.html) Use the forward and next links to read more and find additional references and information.  I believe this is the "Time Nuts" reference that was made a few pages back. I had no idea what "Time Nuts" was referring to at the time.
   Also, I do not understand the full implications beyond "this isn't optimal." I have attempted to read several IEEE papers on the subject as referenced in that mailing list conversation. However, going into this info any further should probably be done elsewhere in another thread.
  This post is simply a reference for those that are interested and because Karl-Heinz included a GPSDO reference in his PDF on Page 124. I have attached an image version of both the Time Nuts message that I felt best explains the issue, and page 124 from KH's PDF for quick and easy reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on October 16, 2017, 04:15:38 pm
...I'm not sure but I think my display is the ST7735.
Yes that is a ST7735 color TFT screen
I loaded the arduinoISP sketch into the arduino and this is as far as I got. I can't figure out the command line string for avrdude to use the arduino and I'm not sure where I need to put the .hex and .eep files I downloaded. Please help!
Follow this post on page 103 (it also continues on page 104) (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1021401/#msg1021401)
Title: Re: $20 LCR ESR Transistor checker project
Post by: turbochris on October 16, 2017, 07:29:47 pm
Thanks for your replies! I'll let you know how it goes. My brain still hurts a little from messing with it I have to let it rest. Mauroh I subscribed to your YouTube, my YouTube name is Krugtech.
Title: Re: $20 LCR ESR Transistor checker project
Post by: turbochris on October 16, 2017, 10:01:02 pm
SUCCESS! another place where I was screwing up was I was using a leonardo, not an uno and the pinout was different. I'm going to mod this thing now, I have a 16 mhz crystal, what would I need to do to be able to use it? I'm also going to get precision resistors and a regulator. Thanks for your help!
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on October 16, 2017, 10:28:56 pm
the regulator is fine, swap the reference - lm341 for a lm4040a

to use 16MHz crystal you just need 16MHz firmware - no other changes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: turbochris on October 17, 2017, 12:07:48 am
Got the 16mhz crystal in on the new style AY-AT tester and found some firmware and it's all good! So the firmware part of that upgrade is done now. next project, this fish8840 based model with a color display- it seems like it has the ISP header and an 8mhz crystal. is there some 16mhz firmware available for it?

(http://img.photobucket.com/albums/v185/serpent99/20171016_195906_zpsud3xqilh.jpg) (http://smg.photobucket.com/user/serpent99/media/20171016_195906_zpsud3xqilh.jpg.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on October 17, 2017, 08:28:50 am
Hi turbochris, glad you was able to fix your unit that easily  :-+

Now that upgrading the firmware is a piece of cake, you can consider also the m-firmware to play with.
As you might know there are 2 main developments/developers of the firmware:
k-firmware manteined by karl-heinz kubblerer (this is the firmware you loaded on your unit)
m-firmware manteined by Markus Reschke (madires here in the forum)

Both great firmwares and great guys!!!

For the k-firmware, there are available the precompiled files for most of the hardware out there and the official folder is here:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)
The fish8840 is present, but for the 16MHz you need to compile it changing the parameter in the Makefile (or someone will provide it to you...)

The m-firmware need to be compiled from source, but for the most common hardwares you can find the compiled files in the forum.
The m-firmware official folder is here:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)
The current version is the 1.29m

Thank you for your interest in my YouTube channel!!! I'm doing my best to be more active  :)
I've watched some of your videos, are you a drag racer?????
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on October 18, 2017, 04:31:55 pm
Not Mastech.  Probably the most useable and practical one out there now.  The tilt display make the meter easier to read.  Left and right button for left and right handed people.  LCD ribbon is not soldered, so burning of new firmware shall be easier.
The other side of PCB shall need to wait.  Desoldering of some thick pins needed and do not look easy :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: turbochris on October 18, 2017, 05:48:47 pm
Hi Mauroh,
I don't race, I have 2 exhibition vehicles, the little bike and minivan. it's better than racing because I get paid to run them without worrying about winning a race  ;D I was on a pit crew for the pro mod you may have seen on my yoube channel but my business has been too busy to find time for that. I work on laser cutting systems up to 6kw for a living.

Compiling the firmware sounds like another good challenge. I'm 57 years old, I need the brain exercise. Thanks for your reply!
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on October 19, 2017, 05:15:22 am
@All Repair
  Thanks for sharing. I would like to see the other side of that PCB if you ever get the chance to take a pic.

It looks like they went with a weird Vref at U2. It looks like it's marked "chw."
I assume that the LM393 is for using PWM to power the LED backlight.
I don't see any input protection.
The ZIF socket for the LCD ribbon cable is a nice touch, along with an actual capacitor discharge resistor/port.
......
  On another note, attached are a few images of what I've been playing around with. While goofing around with a Aneng AN8008 I picked up a few weeks ago I decided to see how well it measures a few 1% resistors that came in a kit. I figure a cheap $25 multimeter would make an interesting way to compare a few 1% resistors with the 0.1% resistors I have. That lead me to the curiosity of how well I can match 5% resistors using this little meter.... Well... See for yourself ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on October 19, 2017, 08:29:15 am
@ turbochris,
   I like the bike, but the minivan is AWESOME!!!
Compiling the firmware is actually easier then programming it.
After installing the AVR tools, you just need to download the source and type "make all -f Makefile" in the folder of your specific hardware where the Makefile is located.
karl-heinz have done a greate job providing the Makefile already configured for so many hardware variants. For the m-firmware you need to change few other parameters, but it is pretty straightforward and well ducumented by madires.
If it goes well you can change the parameters inside the Makefile (like the frequency of the chrystal) and lunch the command again.
Here you can find the step by step instruction on how to build the firmware (thank you flywheelz!!!):
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926)

@ jakeisprobably
I also bought an Aneng AN8008 and pretty happy with it!!!
I was wondering if matching the resistor will really give us better results...
As long as the resistors are  good enouth like 1% and do not drift, the self-test should take into account the small differences in the resistors and also in the ADCs of the atmega. What should be critical is just the Voltage regulator/reference.
M'I missing something? Does the matched resistors really improve precision and or accuracy or something else?

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on October 19, 2017, 11:56:29 am
rrI would like to see the other side of that PCB if you ever get the chance to take a pic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on October 19, 2017, 10:03:48 pm
I also bought an Aneng AN8008 and pretty happy with it!!!
I was wondering if matching the resistor will really give us better results...
As long as the resistors are  good enouth like 1% and do not drift, the self-test should take into account the small differences in the resistors and also in the ADCs of the atmega. What should be critical is just the Voltage regulator/reference.
M'I missing something? Does the matched resistors really improve precision and or accuracy or something else?
Mauro
  I'm definitely a fan of this little 9999 count meter. I'd like to understand more about it but the thread on here is huge already and I don't want to get too distracted. I'm very tempted to get another AN8008 and put it in a bench enclosure though. I've already burned through 4 batteries by using the continuity and diode checker quite a bit.
  The post where Marcus replied to my questions about the resistors and tolerances is here. (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1282842/#msg1282842)
   If I understand it correctly, the probing resistors are extremely important because the software has 1 value attributed to each of the two SETS of probing resistors. This means the device can't calibrate each individual probing resistor value and compensate for the difference between channels. All calculations are based around the idea that 1mA read across test point 1 can and will be 1mA if, for example you reversed the device under test and did the same test sequence again. Of course we are interested in resolution readings that are much smaller than 1mA in resolution.
  Again, IF I understand what Marcus said in the message linked above, the accuracy of the resistor value is not terribly important, the matching tolerance is the key. Basically we can pay for an extremely accurate set of resistors at 0.1% and we end up getting the tolerance we needed. The tolerance of these resistors is a byproduct of their accuracy. If the accuracy of the resistors were important, Marcus would have had a different answer to my question about temperature coefficients. -That bit of info and his reply to my question about 500ohm and 500k resistor parallel combos is where I'm basing my understanding.
  The biggest factor beginners need to understand is the difference between accuracy and tolerance. Accuracy is how close a part is to it's designated value. The only way to know accuracy is with metrology grade equipment or by paying a calibration lab to compare your junk to their super expensive stuff and tell you how wrong you are on a piece of paper and a sticker. Determining tolerance is much easier. Tolerance is determined by resolution based measurements. That one took me awhile to really understand. Hopefully it helps the next person.

  If you look at the measured specs of the resistors I posted before, the 680 1% resistors from my AY-AT clone are at 0.82% total. That's a good bit higher than 0.1% specified in the project and it is a random sample of 1 kit that in no way indicates how good or bad others' devices may be.
   If we are not worried about accuracy and understand that tolerance is key, things change. If we have the ability to measure resistors and compare tolerances at a higher resolution with repeatable results we can create our own high tolerance set. The proper way to do this would probably be with a 5.5 digit or greater resolution meter where the resolution is much better defined.
3.5 digits - 1,999 counts
3.75 digits - 3,999 counts
4.0 digits - 9,999 counts (AN8008)
4.5 digits - 19,999 counts
5.5 digits - 199,999 counts
6.5 digits - 1,999,999 counts
   If I base my measurements on a meter with a tolerance of +3 counts that means I can't trust that last digit to be repeatable. So basically my metrics I posted are total junk to the pros watching my tomfoolery. However my junk measurements have been repeatable in scale on 3 different occasions where I have measured them. The final readings may vary but the same groups of resistors are close in value, and my matched 5% resistors consistently perform far closer in total tolerence than the ones from the kit. Also the 0.1% resistors are the most consistent on multiple measurement sessions. They also show the relative accuracy of the meter as they are probably much more accurate than the meter. I'll be doing more testing soon and will show much more in a video within the next week or so. I'm filming stuff now and have the main schematic version of the tester on a breadboard.
 -Jake
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 22, 2017, 04:10:34 pm
The new firmware 1.30m offers:
- 180° rotated output for ST7920
- bug fix for short circuit detection
- ESR measurement for caps >= 10nF (alternative option: use old method)
- bug fix in basic frequency counter when running the MCU at 20MHz
- support of extended frequency counter (ATmega 644 circuit in Karl-Heinz's documentation, input buffer and LF & HF crystal oscillators)
- option to change dot to comma as indication for a decimal fraction
. a few minor improvements
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on October 23, 2017, 04:37:07 am
 :) :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 24, 2017, 04:40:18 pm
Hi, guys!
Checked work of a new firmware 1.30m from madires on the big display 2.8 inches witch ili9341 SPI https://www.aliexpress.com/item/Free-Shipping-240x320-2-8-SPI-TFT-LCD-Touch-Panel-Serial-Port-Module-with-PCB/32612779225.html?ws_ab_test=searchweb0_0,searchweb201602_2_10152_10065_10151_10068_10344_10345_10342_10343_10340_10341_10541_10540_10307_5640017_10060_10155_10154_10056_10055_10539_10054_10538_10537_10059_10536_5370017_10534_10533_100031_10099_10103_10102_10052_10053_10107_10050_10142_10051_10170_10084_10083_10080_10082_10081_5590017_10110_10111_10112_10113_10114_10312_10313_10314_10078_10079_10073-10102,searchweb201603_25,ppcSwitch_5&btsid=cf3e87a0-bb1d-4fa2-a441-cd06580bb56f&algo_expid=0b86fc84-e0b1-4517-9dde-6c151b51a8fa-11&algo_pvid=0b86fc84-e0b1-4517-9dde-6c151b51a8fa (https://www.aliexpress.com/item/Free-Shipping-240x320-2-8-SPI-TFT-LCD-Touch-Panel-Serial-Port-Module-with-PCB/32612779225.html?ws_ab_test=searchweb0_0,searchweb201602_2_10152_10065_10151_10068_10344_10345_10342_10343_10340_10341_10541_10540_10307_5640017_10060_10155_10154_10056_10055_10539_10054_10538_10537_10059_10536_5370017_10534_10533_100031_10099_10103_10102_10052_10053_10107_10050_10142_10051_10170_10084_10083_10080_10082_10081_5590017_10110_10111_10112_10113_10114_10312_10313_10314_10078_10079_10073-10102,searchweb201603_25,ppcSwitch_5&btsid=cf3e87a0-bb1d-4fa2-a441-cd06580bb56f&algo_expid=0b86fc84-e0b1-4517-9dde-6c151b51a8fa-11&algo_pvid=0b86fc84-e0b1-4517-9dde-6c151b51a8fa)
 Connected it to DIY Kit "AY-AT"(signal data via resistors 10 kOhm).For people who badly see it is good option, a large fonts and signs, madires big respect!  :-+ It would be successful if it is possible to make signs of symbols with higher resolution of 48x48 pixels. It is clear, that in an firmware  for ATMega328 not all functions from set were located, but there is always a choice that is more necessary in work. Firmware in English(for crystal 20MHz) for big display and also files of a configuration i will attach to the message! :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on October 24, 2017, 05:49:38 pm
Nice, I like it!  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: HoracioDos on October 24, 2017, 06:15:08 pm
Hello!

I've been reading this thread since last month and I'm still lost. I bought what I guess it's an AY-AT model with a 12864 display from Alice1101983. I'm looking for the latest firmware and I have no mods.

I'm aware that there are a K (trunk) and M (Markus) firmware versions but I don't know which sub version to download and if I want to download any hex file what I get is a CVS log. Is there any sticky post with upgrade instructions and built binary files?

Thanks in advance!
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on October 24, 2017, 06:24:59 pm
12864 displays are not colour = post a pic or link to your unit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: HoracioDos on October 24, 2017, 06:30:17 pm
12864 displays are not colour = post a pic or link to your unit.

I know it's not colour. That was an example if I click on any hex file. Here is the pic
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 24, 2017, 06:36:52 pm
It would be successful if it is possible to make signs of symbols with higher resolution of 48x48 pixels. It is clear, that in an firmware  for ATMega328 not all functions from set were located, but there is always a choice that is more necessary in work.

You can tweak the symbol's size by changing SYMBOL_RESIZE in ILI9341.c. The defaults for the ILI9341 are  SYMBOLS_32X32_HF (in config_328.h)  and "SYMBOL_RESIZE 2" (in ILI9341.c.), i.e. the displayed symbols are 64x64. You could change that to  SYMBOLS_24X24_HF and "SYMBOL_RESIZE 3" for 72x72. The lower resolution symbols need less flash memory, but they will look more pixelated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 24, 2017, 06:52:37 pm
madires, SYMBOL_RESIZE increases the total area of a symbol, but he doesn't improve his permission and doesn't do it more smooth and accurate? I correctly understand it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on October 25, 2017, 08:34:04 am
Hi Horacio,
     your hardware is usually referred as M12864 DIY Kit and the correct folder for the k-firmware is this:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)

To download the hex and epp files, click on Download GNU tarball.
Then follow this post:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926)

If you want to use a standalone programmer like the TL866, read this.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1156375/#msg1156375 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1156375/#msg1156375)

In any case don't forget the fuses
Mauro

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 25, 2017, 10:22:12 am
madires, SYMBOL_RESIZE increases the total area of a symbol, but he doesn't improve his permission and doesn't do it more smooth and accurate? I correctly understand it?

Yes, SYMBOL_RESIZE magnifies the symbol's bitmap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: HoracioDos on October 25, 2017, 11:35:12 am
your hardware is usually referred as M12864 DIY Kit and the correct folder for the k-firmware is this:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)
Excellent! Thank you very much!!

To download the hex and epp files, click on Download GNU tarball.
:palm: If tarball were a snake I would be already dead.

If you want to use a standalone programmer like the TL866, read this.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1156375/#msg1156375 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1156375/#msg1156375)

In any case don't forget the fuses
You have mind reading powers  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dismounted on October 26, 2017, 01:27:08 am
My AY-AT kit arrived today and I just put together, but... it doesn't seem to work :(

If I push the rotary encoder, the screen's white backlight lights up, but that's about it - once I let go everything turns off again. Any tips on what things I should be checking?

Bought this one: http://www.ebay.com.au/itm/2017-DIY-KITS-GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM/182586325643 (http://www.ebay.com.au/itm/2017-DIY-KITS-GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM/182586325643)
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on October 26, 2017, 06:35:15 am
My AY-AT kit arrived today and I just put together, but... it doesn't seem to work :(

If I push the rotary encoder, the screen's white backlight lights up, but that's about it - once I let go everything turns off again. Any tips on what things I should be checking?

Bought this one: http://www.ebay.com.au/itm/2017-DIY-KITS-GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM/182586325643 (http://www.ebay.com.au/itm/2017-DIY-KITS-GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM/182586325643)
Yap, program first the chip :)

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: Dismounted on October 26, 2017, 08:05:13 am
Yap, program first the chip :)

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk
Ahhhhh yep, that's it! I stupidly thought the chip would come pre-programmed - I guess not...

Flashed with my USBtinyISP and it all works now, thanks! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 26, 2017, 01:10:34 pm
Hi, madires!
Error in case of compilation 1.30m if to include check of servo RC.  File extras.c with a line 793.
1.29m line 787 it is correct!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 26, 2017, 04:39:47 pm
Yes, that's an edit error. Please change in Servo_Check()

Code: [Select]
  #define FLAG_RUN       0b00000001     /* run / otherwise end */
to
Code: [Select]
  #define RUN_FLAG       0b00000001     /* run / otherwise end */

Thanks for reporting!
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on October 27, 2017, 11:06:19 am
Yes, that's an edit error. Please change in Servo_Check()

Code: [Select]
  #define FLAG_RUN       0b00000001     /* run / otherwise end */
to
Code: [Select]
  #define RUN_FLAG       0b00000001     /* run / otherwise end */

Thanks for reporting!

Modification done and already compiles well.

Thank you very much.
Title: Re: $20 LCR ESR Transistor checker project
Post by: cape zoloh on October 27, 2017, 01:06:56 pm
Can one of these be recommended over the others? Is there a "best one" of all these variations?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on October 27, 2017, 02:22:24 pm
AY-AT colour kit is the best if you want to be able to expand it or upgrade the firmware in the future.
if your just looking to use it then there is a cased unit that also tests zeners with an internal lithium battery - i think called T7?
Title: Re: $20 LCR ESR Transistor checker project
Post by: boffin on October 28, 2017, 03:29:58 pm
If people here are looking for the two-step simple way of having the tools for compiling, this is about as basic as you can get  (assuming you already have the Arduino suite installed on your PC)

Title: Re: $20 LCR ESR Transistor checker project
Post by: flixHr on October 28, 2017, 05:01:22 pm
Hi,
I have a problem with my tester and and did not find any hints in this forum so far. I managed to reflash the microcontroller no problem. But the device turns itself off very quickly after each test. So quickly even that it is quite hard to read the result :(. I tried to edit the POWER_OFF option in the makefile and even tried to change the LONG_WAIT in the config.h file but nothing changed anything. Has anybody any idea what count be the cause for this? Am I overlooking something stupid?

Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on October 28, 2017, 06:05:43 pm

I have a problem with my tester ...
1st.. plz tell something more, the are hundreds of variations all around, nobody knows what's your's..
2nd.. IIRC one or two y ago such a prob was discussed in thn german HOME forum, plz have a closer look at mikrocontroller.net (AVR Transistortester or similar), Karl-Heinz has a lot of experience with thousands of faults, feel free to ask ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bianchifan on October 28, 2017, 06:20:19 pm
AY-AT colour kit is the best ...
I cannot consent at this very moment..
Some weeks ago I ordered such a kit from aliexpress, ok, the cheapest i could find, ~ 9$  :-DD
I recieved a bunch of fuckin' crap!
I ordered for two reasons, I heared from several people about many problems making this kit run so I wanted to try for myself and I liked to get a tester for checking out the "M" firmware.
The PCB is damaged (looks like rejecting stuff), the MCU is programmed with something whatever but a running FW..

There maybe sellers with kits ok of course, but not all.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flixHr on October 29, 2017, 12:27:31 am
1st.. plz tell something more...

I must admit, that was not quite the information needed.
My unit was sold as LCR-T4 and has the ST7565 display controller and an atmega328p micro controller.
I flashed the newest revision of mega328_T3_T4_st7565, mega328_st7565 and mega328_st7565_kit but always got the same problem. The tester shuts itself off immediately after the test is complete.
I made my own firmware by changing the POWER_OFF option in the makefile and changing LONG_WAIT_TIME and MIDDLE_WAIT_TIME in config.h.
I even got the same behavior when flashing 1.30m.

So has anybody seen this strange behavior before or has any hints into what direction to look?
Any help is much apreciated  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: nakcho on October 29, 2017, 03:05:38 am
AY-AT colour kit is the best if you want to be able to expand it or upgrade the firmware in the future.
if your just looking to use it then there is a cased unit that also tests zeners with an internal lithium battery - i think called T7?
good morning to all who participate in this forum ... I am entering the subject and trying to understand a little this operation ... I am not an expert .. I am a student ... I like the idea of ??this tester .. I wanted to know if there is any possibility that they tell me how I can install the ST7735R display or how it would be the configuration in proteus of this display ... because I see many connectors I can not make it work .. .. someone to help me please
(https://k61.kn3.net/E/C/1/3/4/D/025.png)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 29, 2017, 11:13:44 am
I flashed the newest revision of mega328_T3_T4_st7565, mega328_st7565 and mega328_st7565_kit but always got the same problem. The tester shuts itself off immediately after the test is complete.
I made my own firmware by changing the POWER_OFF option in the makefile and changing LONG_WAIT_TIME and MIDDLE_WAIT_TIME in config.h.
I even got the same behavior when flashing 1.30m.

Does the tester power up and display the battery voltage?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 29, 2017, 11:19:21 am
good morning to all who participate in this forum ... I am entering the subject and trying to understand a little this operation ... I am not an expert .. I am a student ... I like the idea of ??this tester .. I wanted to know if there is any possibility that they tell me how I can install the ST7735R display or how it would be the configuration in proteus of this display ... because I see many connectors I can not make it work .. .. someone to help me please

Please see the schematic for the AY-AT kit. You can find several copies in this thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flixHr on October 29, 2017, 12:42:06 pm
Does the tester power up and display the battery voltage?
Yes the tester powers up normally and performs the test. It is quite slow to start the test but i don't know if that is normal.
But after the test the device powers off immediately.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 29, 2017, 04:18:43 pm
Could you please post the fuse settings?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flixHr on October 30, 2017, 08:51:12 pm
Hi,
After some poking around and measuring all the MCU pins I finally fount the cause for my wired behavior. The Problem was a bad transistor constantly pulling PD7 to ground. I did not notice this before as the tester did turn on regardless of the broken transistor because the unit would power on through the PNP transistor at the input and would turn off through the second working NPN transistor. So i replaced the burned transistor and everything works again.
Thanks for your reply anyway!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: nakcho on November 02, 2017, 12:12:39 pm
good morning to all who participate in this forum ... I am entering the subject and trying to understand a little this operation ... I am not an expert .. I am a student ... I like the idea of ??this tester .. I wanted to know if there is any possibility that they tell me how I can install the ST7735R display or how it would be the configuration in proteus of this display ... because I see many connectors I can not make it work .. .. someone to help me please

Please see the schematic for the AY-AT kit. You can find several copies in this thread.
HELLO ... I APPRECIATE THE INSISTENCE BUT I DO NOT HAVE EXPERIENCE WITH DISPLAY AND I DO NOT FIND THE WAY TO CONNECT IT TO THE ONE I LEFT IN THE CAPTURE ... YOU ONLY GIVE ME A HAND IN THAT PLEASE .. I HAVE DOWNLOADED A PDF WITH THE DISPLAY CONNECTION MODES BUT THAT BUT DISPLAY ST7735R NOT FIGURE ... THIS IS THE VERSION WITHOUT THE FINAL R THAT NOSE IF IT WILL BE THE SAME ... YOU GIVE ME A HAND WITH THE CONNECTION PLEASE
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on November 02, 2017, 02:10:09 pm
@nakcho,
Yelling is not what you should do on a forum like this (Using only capitals).
Also it might be a lot more readable if you are using normal lines of text.
Perhaps you have then more chance to be helped by someone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2017, 05:05:07 pm
No need to shout! >:( You need to use the SPI mode (4-wire serial mode) and have to add a level shifter, since the controller runs with 3.3V. If you're lucky, your LCD module might already have a 3.3V LDO and a level shifter on board. My ST7735 modules only got the 3.3V LDO. Jake (jakeisprobably) posted a link to his AY-AT schematic (too large for uploading here in the forum) which depicts the level shifter and all you need to know.
Title: Re: $20 LCR ESR Transistor checker project
Post by: myattorneyusa on November 03, 2017, 01:54:27 am
Could anyone post .eep, .hex file for AY-AT, please? Firmware M v1.30m or v1.3k + English + VEXT + Check Rotary Encoder + PWM Plus + Zener 
I have hard time compiling it from source. Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: nakcho on November 03, 2017, 02:29:35 am
No need to shout! >:( You need to use the SPI mode (4-wire serial mode) and have to add a level shifter, since the controller runs with 3.3V. If you're lucky, your LCD module might already have a 3.3V LDO and a level shifter on board. My ST7735 modules only got the 3.3V LDO. Jake (jakeisprobably) posted a link to his AY-AT schematic (too large for uploading here in the forum) which depicts the level shifter and all you need to know.
I apologize ... the truth does not tell me about the capital ... I was very focused on this project ... so I focused only on what I needed help ... a thousand apologies ... very good forum
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 03, 2017, 12:34:44 pm
I'm working on the 180° rotated output for PCD8544 based LCD modules at the moment. Someone asked for that feature a while ago. Are there any suggestions for other LCD modules to support?
Title: Re: $20 LCR ESR Transistor checker project
Post by: marklein on November 05, 2017, 05:17:03 pm
I have a pre-assembled AY-AT unit and it worked great for a month or two... now it won't power on.  :'( Right in the middle fixing a television too!  |O Now that it's gone I realize how much I used it. I don't want to wait another month for a Chinese replacement and I'm not sure that the ones on Amazon US have the latest firmware installed (anyone know?).

I was testing a capacitor at the time and I wonder if maybe the cap was charged and that caused the failure(?), but it wasn't a very big cap which is why I didn't think to discharge it so I don't know.

Anyway, are there any known issues or obvious things I can check? Thanks folks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 05, 2017, 06:57:56 pm
check the transistors and 5v regulator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on November 06, 2017, 04:41:12 pm
I was testing a capacitor at the time and I wonder if maybe the cap was charged and that caused the failure(?), but it wasn't a very big cap which is why I didn't think to discharge it so I don't know.

It is NOT the SIZE of a charged capacitor that will damage your tester but the VOLTAGE that the capacitor is charged to.
Title: Re: $20 LCR ESR Transistor checker project
Post by: progrock on November 07, 2017, 02:03:56 pm
OK, so I randomly ran into one of these testers today on aliexpress... and then totally randomly landed on this forum and saw this thread (I honestly don't even remember why I came to the forum in the first place, but wasn't for this).

So, it looks like i was lucky I didn't click order yet, I was about to buy a pre-assembled AY-AT clone... but if I'm understanding things correctly, I probably want to buy the DIY assembly kit, and upgrade a few parts.  Either that, or is it recommended to go and print your own PCBs from the official tarball? (When I followed the most recent link I could find to this tarball, it did not allow me to download, there seemed to be some kind of server error.

My current plan is to order one of these kits: https://www.aliexpress.com/item/2016-DIY-kits-ATMEAG328-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Frequency/32815242766.html (https://www.aliexpress.com/item/2016-DIY-kits-ATMEAG328-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Frequency/32815242766.html)

Then, instead of using all the parts the kit comes with, replace some of them with the parts listed here: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1284997/#msg1286025

Is that pretty much the "correct" route to go?... or did I miss something.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on November 07, 2017, 04:21:33 pm
Yes that is good, nice first post :)
I would make one change: I'd get a 16Mhz crystal too.
That way you can choose either the M firmware or K firmware.
See the following post:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1286135/#msg1286135 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1286135/#msg1286135)

Also you should have a 100nF > 1000nF film capacitor when calibrating the unit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: progrock on November 08, 2017, 01:47:34 pm
OK, awesome.. thank you for confirming (and seriously confused at how the hell I got to this thread in the first place yesterday... really strange, especially since I had the rebuilt one in my cart, and was gonna pay a few hours before, but got side tracked).  Of course, as usual, now my cart has been expanding.... was also about to build a simple/cheap DIY bench power supply, then saw one of the recent blog videos, and now I have a RD DPH3205 and a DPS5015, lol...

From the skimming I did yesterday, seemed like the M firmware was a solid/popular choice (though I did not look into/compare the K firmware yet)... but thanks for the recommendation... should be easy enough to find one on aliexpress... but does anyone have a specific 16Mhz crystal they would recommend?

**EDIT: Or is aliexpress not the best place for something like that... of course I just got an order from arrow today... guessing they would make more sense... but still open to suggestions if theres a specific on recommended
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on November 08, 2017, 04:48:17 pm
AliExpress is fine, that is where I got my kit including the 16MHz crystal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on November 08, 2017, 05:51:27 pm
Look e.g. at:
https://www.aliexpress.com/wholesale?catId=0&initiative_id=AS_20171108094714&SearchText=Eldoer+10PCS+A+LOT+Mini+Passive+crystal (https://www.aliexpress.com/wholesale?catId=0&initiative_id=AS_20171108094714&SearchText=Eldoer+10PCS+A+LOT+Mini+Passive+crystal)
10 pieces for a very small price 😋
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on November 08, 2017, 08:51:03 pm
I bought 100 16 MHz xtals off of Ebay for $5 shipped from China.  Figured they would be crap, but were surprisingly good.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 08, 2017, 11:21:29 pm
that sounds very cheap till you realise you dont actually need the other 99!!  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on November 08, 2017, 11:52:24 pm
that sounds very cheap till you realise you dont actually need the other 99!!  :-DD

I've used over half of them.   I once spent a day doing tests on each one to find a "really good" one.  Total waste of time... they were all  surprisingly good and practically identical in what I was testing for. 

Decent crystals for 5 cents a whack... no way!  Next thing you will tell me is I can get rather nice GPS modules with an antenna for $7 a pop... oops, been there, done that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: progrock on November 09, 2017, 05:58:41 pm
Thanks for the links... but I bough all the parts needed to upgrade the aliexpress model to the "improved" version off arrow.com today... the Crystal was under 50 cents anyway... and everything is coming with free overnight shipping (not to mention arrow is insane with their packaging, so each part will be in it's own separate static bag, nicely labeled, etc).  Bought enough to build 2 of these, plus a few spare parts just in case.  Of course I still have to wait for the board(s) to get shipped from China... but oh well.

Sadly, I need to test a handful of MOSFETs on an arduino based spot welder I have that is failing... seems like this board would be perfect for that... but I believe its not too hard to accomplish with my fluke multimeter... just a few step process for each mosfet if I'm not mistaken.  But definitely glad to find this device to make things a little easier in the future.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 09, 2017, 07:02:33 pm
something i noticed with intermittent or slightly questionable mosfets is you often find the reverse-diode has vanished / failed open-circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: progrock on November 10, 2017, 12:25:45 am
I'll have to check that out... I know they are pretty good mosfets (well, tried and true at least)... legit (not a chinese copy) IRF1404.  Just gotta desolder a couple of layers of PCBs to get to them, and figure out the correct way to test with my Fluke 15B+... never tested any FETs with it before (actually, last time I tested a FET was nearly 10 years ago in a college electronics lab... and I've done my best to forget pretty much everything I learned at school, all I have is a piece of paper saying I have a CoE degree at this point)... it appears to have the mode I need to test, tho it's one of only 2 modes that don't have a direct mode (as in you spin the dial to select Ohms, then it appears to have 2 optional modes from there, one being what I believe is the mode needed to test a mosfet).

Def glad I'll have one of these guys next time I need to do this (hopefully).
Title: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 10, 2017, 07:38:47 am
something i noticed with intermittent or slightly questionable mosfets is you often find the reverse-diode has vanished / failed open-circuit.
For a real mosfet the diode dies first generating a short. Anyway good practice is putting external diode for power applications like inverters where the returning energy anyway is not "eated" by the internal diode.

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Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 10, 2017, 03:09:21 pm
well i noticed the problem when repairing low current backlight invertors in lcd tv's & monitors.

often when a fet shorts, you find the diodes are failing or gone in the remaining parts - so i used to change them as a set.
Title: Re: $20 LCR ESR Transistor checker project
Post by: progrock on November 10, 2017, 07:44:31 pm
Thanks, great advice, and may have saved me from another headache.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 11, 2017, 07:40:06 am
well i noticed the problem when repairing low current backlight invertors in lcd tv's & monitors.

often when a fet shorts, you find the diodes are failing or gone in the remaining parts - so i used to change them as a set.
Never noticed thanks for pointing out!

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Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 11, 2017, 06:34:23 pm
I've started to write drivers for ILI9163 (SPI) and SSD1306 (SPI & I2C), and ordered a few displays. Hopefully the ILI9163s are not ST7735s, since they are quite similar. Many display descriptions are unclear about what you get.
Title: Re: $20 LCR ESR Transistor checker project
Post by: marklein on November 15, 2017, 03:22:44 am
Are all the various AY-AT boards interchangeable, or are there layout/circuit/values differences? In other words could I take the ATMega from one board and swap it with the ATMega a different board and expect them to work? THX

I have one dead tester and one good one, and the ATMega from the dead unit doesn't display anything in the known good board, but they are different vendors and revisions so...  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 15, 2017, 04:00:51 am
they should be the same if they both say "AY-AT" on them.
either way, you cant damage anything by swapping controllers around - the critical pins are fixed. (power, crystal etc.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stevelup on November 15, 2017, 07:52:10 am
The primary variations are the display type and the pins used for connecting the display. If they are both using the same display type, and the display is connected in the same way, the processors should be interchangeable.
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on November 16, 2017, 02:16:27 am
Love this epic thread  :popcorn:

Love my evilbay tester. Crammed it into an old 2.5" Sata drive case I had. To save losing SMD components in the case I used a garden tap washer glued to the board which is a neat fit to the top of the case. Some cheap and nasty clips fitted to a header go in the Sata pouch in the toolbag.

Currently it has an 8-20V Linear regulator and a Deans Mini plug fitted to the end. So fairly much any external DC supplies to power it. I might fit up an internal LiPo/Charger etc but cells are to fat 8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 16, 2017, 07:23:21 am
Love this epic thread  :popcorn:

Love my evilbay tester. Crammed it into an old 2.5" Sata drive case I had. To save losing SMD components in the case I used a garden tap washer glued to the board which is a neat fit to the top of the case. Some cheap and nasty clips fitted to a header go in the Sata pouch in the toolbag.

Currently it has an 8-20V Linear regulator and a Deans Mini plug fitted to the end. So fairly much any external DC supplies to power it. I might fit up an internal LiPo/Charger etc but cells are to fat 8)
For God's sake put black screws :)

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Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on November 16, 2017, 07:34:55 am
Picky Picky Picky  :-DD

3mmx8mm "black" countersunk screws in country Australia don't grow on trees. Only the dropbears do ;)

Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 16, 2017, 07:50:31 am
Picky Picky Picky  :-DD

3mmx8mm "black" countersunk screws in country Australia don't grow on trees. Only the dropbears do ;)
Sorry the French people I'm working taught me it have to be nice, if it works that's secondary.
Anyway, paint the dam.ed screws.
Kidding, again

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Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on November 17, 2017, 05:44:23 am
Love my evilbay tester. Crammed it into an old 2.5" Sata drive case I had.

That's a good idea. Add it to the $20 transistor tester enclosure thread (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/), too. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 17, 2017, 09:36:59 pm
enclosures are for "users", engineers dont need enclosures.  >:D
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on November 17, 2017, 10:15:08 pm
LOL. Yeah, the lab is the enclosure.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nakcho on November 18, 2017, 03:36:25 am
ood collaborators of the forum ... I have a compontens tester on the board says 2578AY-AT I miss the firmware is the white screen a while and nothing happens ... uh .. tried to burn a firmware but none successful does not show me nothing ... I do not know what is wrong ... one of the firmware I get 99 ::: 99 and then it turns off the only thing I want is to recover my tester can I get a link with the correct firmware? I am using Extreme Burn 1.4 ... I do not know if it will be fine but what I do is put the memory to erase and load the new Hex ... nose if I had to configure something else in the program ... please can you help me. .. as I said the only thing I want is to recover my tester ... from now thank you very much
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on November 18, 2017, 09:30:38 am
If flashing new firmware, do not forget to set the FUSES correctly, please!


SVN firmware repository "mega328_color_kit" folder:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/)

I still use the SVN 700 compilation from STJ (attached).
Title: Re: $20 LCR ESR Transistor checker project
Post by: nakcho on November 18, 2017, 12:15:57 pm
If flashing new firmware, do not forget to set the FUSES correctly, please!


SVN firmware repository "mega328_color_kit" folder:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/)

I still use the SVN 700 compilation from STJ (attached).



again ... excuse my gnorancia .... I'm in full fight with this ... I attached an image of the fuse settings please help me ... install the firmware and only the voltage appears ... and then it turn off I think it is due to lack of fuse settings --- you help me with the correct configuration of the fuse? the crystal is 8Mhz
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2017, 01:17:35 pm
For ATmega328 with external 8MHz crystal:
Low Fuse: f7
High Fuse: d9
Extended Fuse: fc
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on November 18, 2017, 01:19:21 pm
Parte baja Fusibiles = F7
Parte alta Fusibiles = D9
Fusibles extendidos = FC
Fusibles de Bloqueo = Do NOT select "escribir" on this one, it is used for write lock
Calibración = No idea what "calibration" this is for.

This should correspond to:
\-U lfuse:w:0xf7:m \-U hfuse:w:0xd9:m \-U efuse:0xfc:m

EDIT: madires was quicker to write than me ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2017, 07:37:30 pm
Calibración is the adjustment value for the internal RC oscillator. You don't need to update or change that value.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on November 19, 2017, 09:41:01 pm
For ATmega328 with external 8MHz crystal:
Low Fuse: f7
High Fuse: d9
Extended Fuse: fc

Is this setting for 16MHz too?

Thanks for answering.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 19, 2017, 10:47:36 pm
yes
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on November 20, 2017, 08:46:07 am
Thanks STJ.
Title: Re: $20 LCR ESR Transistor checker project
Post by: turbochris on November 21, 2017, 10:31:30 pm
QUESTION!- I have a few lipo cells with protection circuits and some of these micro USB charge controllers with 9 volt boost converters built in. I have the newest AY-AT PCB based tester. I'm going to put the lipo and charge controller/boost converter on it. How can I run the vbat signal that goes to R1 directly to my battery so i can see battery actual battery voltage and not the converter output voltage? Would I need to add another transistor like T1 between the battery and sense circuit to keep the voltage divider on the sense circuit from killing the battery?
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 22, 2017, 07:19:30 am
QUESTION!- I have a few lipo cells with protection circuits and some of these micro USB charge controllers with 9 volt boost converters built in. I have the newest AY-AT PCB based tester. I'm going to put the lipo and charge controller/boost converter on it. How can I run the vbat signal that goes to R1 directly to my battery so i can see battery actual battery voltage and not the converter output voltage? Would I need to add another transistor like T1 between the battery and sense circuit to keep the voltage divider on the sense circuit from killing the battery?
You won't kill a battery with a divider with correct values. Unless you don't use the charger for months. Avoid charging the battery with the tester connected. That's all

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Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 22, 2017, 08:01:52 am
QUESTION!- I have a few lipo cells with protection circuits and some of these micro USB charge controllers with 9 volt boost converters built in. I have the newest AY-AT PCB based tester. I'm going to put the lipo and charge controller/boost converter on it. How can I run the vbat signal that goes to R1 directly to my battery so i can see battery actual battery voltage and not the converter output voltage? Would I need to add another transistor like T1 between the battery and sense circuit to keep the voltage divider on the sense circuit from killing the battery?

The decision from the user Vepr from the Russian forum vrtp.ru  http://vrtp.ru/index.php?showtopic=25020&view=findpost&p=745685 (http://vrtp.ru/index.php?showtopic=25020&view=findpost&p=745685)  :D
"I used  of the boost converters on 5v, having soldered in it to the place of IC1 7550 (stub. 5Volt).
I replaced the R17 220 resistor of Ohms with the low-impedance 0-50 Ohms (I increased illumination brightness)
The R18 3k3 resistor replaced with free 220 Ohms.
In a code I corrected a supply
CFLAGS + = - DBAT_OUT=10
CFLAGS + = - DBAT_POOR=3300
The module for accumulator charging with protection set in a rupture of the power connector.
As a result to the T1 emitter comes 4 Volt from the accumulator, on an output IC1 - 5 Volt, need for the supply switch disappeared..."
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on November 22, 2017, 11:41:48 pm
Howdy,
https://youtu.be/9cg7pBUUv94

I'm still having too much fun with the simple stuff ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: aabbcc on November 23, 2017, 08:52:05 am
So I got the Dainu TC-1, is it accurate enough to match transistors for vbe (need to match a bunch of BC547 & BC557).

I tried measuring the same transistors a few times and it almost every time gave me different vbe lol, from 678-692 :S

(https://i.ytimg.com/vi/oij9JLOIHs0/hqdefault.jpg)
https://www.banggood.com/DANIU-3_5inch-Colorful-Display-Multi-functional-TFT-Backlight-Transistor-Tester-p-1083042.html?rmmds=search (https://www.banggood.com/DANIU-3_5inch-Colorful-Display-Multi-functional-TFT-Backlight-Transistor-Tester-p-1083042.html?rmmds=search)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 23, 2017, 09:56:03 am
variation is probably down to the crap contacts in the green chipsocket
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 23, 2017, 12:13:39 pm
Maybe also temperature related for small transistors if you put your fingers maybe changes vbe a little. I'll try myself to verify...

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Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on November 23, 2017, 03:16:18 pm
I tried measuring the same transistors a few times and it almost every time gave me different vbe lol, from 678-692 :S
  The AVR Transistor Tester design isn't intended as a precision device, and no clone to date uses the 0.1% resistors or the 0.1% voltage reference specified in the documentation. The software is very impressive for it's capabilities with simple hardware.
  Like most clones you probably have a relatively large difference between the probing resistors on each ADC sensing pin. The software can only have one value attached to the 680R and 470k probing resistors. This is why the design specifies 0.1% resistors. In this case it is the tollerence that matters, not the accuracy. Each 680R/470k resistor needs to be closely matched, but it doesn't matter if the resistance is extremely accurate. The variance between channels is important. Your voltage reference is also creating accuracy error because the reading that the TT is giving you assumes you've used a 2.5 volt reference with 0.1% accuracy. The TL431A reference used in clones has a tolerance 10 times larger than the specified accuracy of the design as listed in the documentation.
(Edit: A cheap replacement voltage reference option is here. (http://s.aliexpress.com/rMjYram6) I haven't tested them yet, but that's what I ordered to try on an SMT clone. The pinout is different than the TL431A, but the LM4040 DS says you can leave the Vref pin floating, so it should work by simply soldering it diagonally without a jumper or other mods.)

I was under the impression that we need to stair step the voltages to gather a more 3 dimensional understanding of transistor Hfe and Vbe curves for matching. If you have an oscilloscope Allen has some great tutorials on different ways to build a simple curve tracer on his A2AEW YouTube channel. Specifically his videos numbered #232, #197, and #49.

   My curiosity about curve tracers is if there is any potential to add one as a project option to the AVR TT. I know people have created "Arduino" oscilloscopes that will run on controllers as small as the ATmega8. I wonder if we use one or two 74HC4052's (dual 4 channel analog MUX/DEMUX) and reconfigure the Zener threshold DC to DC boost converter, could we create a curve tracer option?
   I've seen one project on YouTube that used an Arduino oscilloscope reconfigured in a XY mode to create a curve tracer. (Thinking out loud here) I wonder if a 4052 could be used to control a feedback resistor network on a DC converter while expanding the AVR's I/O and protecting it from over voltage/current.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 24, 2017, 11:54:41 am
Might be possible with the additional I/O pins of the ATmega644/1284. There was an idea to support higher test voltages than just 5V (and higher test currents), but that would require an external switching network. For the sake of simplicity we've dropped that idea. IMHO, it would make more sense to build a curve tracer front-end for a scope.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on November 25, 2017, 04:43:06 am
I still need to figure out a way to organize stuff on my computer and upload that to Git but here is the start:
https://github.com/Upcycle-Electronics/AVR-Transistor-Tester

I added some of the PDF's I have created, some were posted on here, some are not, some are works in progress. Once I figure out how to reorganise all of the KiCAD parts libraries I have created, I'll try to upload the active project files so anyone with KiCAD can goof around with them if they want ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: cbc02009 on November 25, 2017, 02:41:44 pm
Hi guys,

I recently bought this kit (https://smile.amazon.com/gp/product/B01HCXG9YS/) but I pulled a stupid and burned the arduino bootloader on to it. (i had to us it as an ISP to recover a bricked arduino mega, and somehow forgot it would wipe the program already on it  :palm:). I've been trying to figure out how to get the program back on the chip, but I'm really having trouble figuring it out. If there's anyone that could point to some help, or walk me through it, I would really appreciate it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on November 25, 2017, 02:57:24 pm
Is it unmodified?

If so. Try burning these via ISCP https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_color_kit

Can use AVRDudess or whatever your choice is for avrdude usage. :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on November 25, 2017, 03:40:50 pm
I've been trying to figure out how to get the program back on the chip, but I'm really having trouble figuring it out. If there's anyone that could point to some help, or walk me through it, I would really appreciate it.
I've been having trouble making these links work with copy and paste. Maybe they will work here. If not I have included page number references. I've been working on a tutorial video on programming but I need a few parts in the mail to finish a hacked together USBasp programmer enclosure first...so I'm no help ;/
USBasp by Tom666 on page 60 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg797245/#msg797245)
Arduino ISP by Tom666 on page 59 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg793722/#msg793722)
Arduino ISP by Flywheelz with AY-AT example on page 103 (continued on 104) (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1021401/#msg1021401)
Title: Re: $20 LCR ESR Transistor checker project
Post by: cbc02009 on November 25, 2017, 04:15:45 pm
Is it unmodified?

If so. Try burning these via ISCP https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_color_kit

Can use AVRDudess or whatever your choice is for avrdude usage. :)

Thanks, I'll give it a try this afternoon. Much appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nakcho on November 26, 2017, 10:10:59 pm
If flashing new firmware, do not forget to set the FUSES correctly, please!


SVN firmware repository "mega328_color_kit" folder:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/)

I still use the SVN 700 compilation from STJ (attached).



again ... excuse my gnorancia .... I'm in full fight with this ... I attached an image of the fuse settings please help me ... install the firmware and only the voltage appears ... and then it turn off I think it is due to lack of fuse settings --- you help me with the correct configuration of the fuse? the crystal is 8Mhz

HELLO ... I HAVE
2578AY-AT AND MY ORIGINAL FIRMWARE WHEN INICIAVA DECIA 1.12K ... WHICH WOULD THAT FIRMWARE WOULD .. I WOULD LIKE TO INSTALL THE SAME AGAIN ... SINCE THAT ME WORKSAVE PERFECT ... YOU COULD PASS ME THE LINK ... PLEASE TO THAT VERSION?
Title: Re: $20 LCR ESR Transistor checker project
Post by: frozenfrogz on November 26, 2017, 11:01:38 pm
I drew a case for the GM328A model and upped it here on Youmagine (https://www.youmagine.com/designs/case-for-gm328a-component-tester).
It is the first version and may need some refinement to give better printing results for the top shell.
My first print was OK-ish but needed some putty to fix the surface (printed upside-down with support).
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 27, 2017, 01:21:41 am
 8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: nakcho on November 28, 2017, 05:52:44 pm
8)
Good morning I need a little help that I do not know what to do ... I've tested the firmware AY-AT ESR tester (SVN749) .. first then after recording the frimware I turn on the tester is the screen in blue 1 min 30 sec apox then aprace some data as the battery and version I guess ... after that the word short probe appears! After shorting pins 1-2-3 starts to do some kind of test .... then it remains in CO for a while .. after that it remains with the screen in 100nf (I put a capacitor of 100nf). but then nothing comes out ... not even pressing the reset button or moving the decoder ... any idea
'It has a crystal of 8mhz ... will it be for that reason what takes so long? between one screen and another? ... if so, I would only open it to change for a 16 mhz help please ... I need to recover
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on November 29, 2017, 12:24:05 am
try calibrating using a 220nF capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ncclabs on November 29, 2017, 02:56:52 am
I designed my own style  8)
(https://i.imgur.com/xdDzPBh.jpg)
(https://i.imgur.com/UQloBVU.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on November 29, 2017, 04:26:12 am
Welcome to the forum, ncclabs. That's a nice clean "case." I'd probably mount the top PCB higher so that the ribbon cable on the LCD could be covered. It'd give it some protection and look cleaner.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ncclabs on November 29, 2017, 07:42:56 am
Welcome to the forum, ncclabs. That's a nice clean "case." I'd probably mount the top PCB higher so that the ribbon cable on the LCD could be covered. It'd give it some protection and look cleaner.

Thank you for your comment, when finished the product will consist of 4 PCB (currently only 2 PCB)


Title: Re: $20 LCR ESR Transistor checker project
Post by: progrock on November 29, 2017, 08:27:39 am
I finally got all my parts, and got around to start building this thing... I've been using the diagrams in this post: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1295664/#msg1295664 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1295664/#msg1295664)

The post says that C13 should be 22nF.... while the board says "104"... 100nF.  I'm guessing the 22nF is probably correct.... hopefully I can salvage one from somewhere else.... but can anyone confirm this?

Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on November 29, 2017, 09:51:53 am
I use the "original" value of "104" (0.1uF) and it works just fine with it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: doc sylver on November 29, 2017, 01:46:33 pm
Hello,
I built this montage and I wonder how to put the menu in French?
I saw on the github language files, but I do not know how to change the language?
Could you help me ?.
A big thank you in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: progrock on November 29, 2017, 02:16:10 pm
OK, cool.  BTW, is there any "re-wiring" needed? or just need to replace those few parts... Crystal (16mhz), vref, v regulator, the 6 resistors...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2017, 05:22:25 pm
I built this montage and I wonder how to put the menu in French?
I saw on the github language files, but I do not know how to change the language?
Could you help me ?.

For the k-firmware set your preferred language in the Makefile, e.g. LANG_FRANCAIS.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2017, 05:24:59 pm
OK, cool.  BTW, is there any "re-wiring" needed? or just need to replace those few parts... Crystal (16mhz), vref, v regulator, the 6 resistors...

The LDO and the voltage reference might have a different pinout. Besides that you can simply swap the parts. And re-compile the firmware for 16MHz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on December 02, 2017, 02:47:30 pm
Complete circuit retraced (not just the power circuit)
https://youtu.be/LHoMMMbiSXo

The final schematic pdf is available on my GitHub page asTT-Clone-littlet2.pdf (https://github.com/Upcycle-Electronics/AVR-Transistor-Tester)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 02, 2017, 03:02:01 pm
Quick update on the m-firmware development. The ILI9163 displays have arrived and are working fine after fixing some minor issues. The  SSD1306 OLEDs are expected to be delivered next week. The indicator for a selected menu item got color support. The same for selected parameters in a few tools. I'm working on a new feature (top secret :) ) and hope that I get it done until xmas.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on December 02, 2017, 05:47:12 pm
@madires
Noted. Your adding the ILI9163.

Looking through your code I don't see any references to the KS0108/NT7108 LCD driver. I assume you do not want to support these displays? These are the two that require 8 bit parallel connections and a 74HC164 or 74HC595 to reduce the IO pins required. It's a shame the KS0108 doesn't have an SPI interface. I haven't tried the ST7920 with a transistor tester yet, but after running a test Arduino sketch on it, I learned about the lack of a memory buffer on the driver IC. I imagine that display really limits the code size for the project. How bad is this display in practice? Is it limited to the basic circuit function only?

BTW I have been going through the 'how to program the device on Linux' section of KH's PDF over the last couple of weeks. I rewrote the whole section although I'm still going to modify the part about serial programming/ArduinoISP. I'm also going to try to hook up an old Windows PC to go through everything again to document. I sent the Linux text to KH already, but the simple text is also available on my GitHub page. I don't know if KH will modify the PDF but I tried. It's basically my personal notes from trying to develop a video guide one of these days. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: doc sylver on December 02, 2017, 05:52:03 pm
hello madires,
thank you for your answer, it works , me has read it in the doc and I already had try, but unsuccessfully.
I have just brought up to date some files of WINAVR and there, this walks, perhaps also an error of me?.
Still thank you and good day.
Doc Sylver.
(excuse me for my bad english  ;))
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 02, 2017, 06:30:32 pm
Looking through your code I don't see any references to the KS0108/NT7108 LCD driver. I assume you do not want to support these displays? These are the two that require 8 bit parallel connections and a 74HC164 or 74HC595 to reduce the IO pins required. It's a shame the KS0108 doesn't have an SPI interface.

Nobody has asked for a KS0108 driver so far. If someone likes to sponsor one or two KS0108 displays, please PM me.

I haven't tried the ST7920 with a transistor tester yet, but after running a test Arduino sketch on it, I learned about the lack of a memory buffer on the driver IC. I imagine that display really limits the code size for the project. How bad is this display in practice? Is it limited to the basic circuit function only?

The ST7920 has several buffers. One for a few custom characters (bitmaps), one for the characters and another one for the graphics mode. The big PITA is the addressing in graphics mode, but that doesn't have much impact on the firmware size.

BTW I have been going through the 'how to program the device on Linux' section of KH's PDF over the last couple of weeks. I rewrote the whole section although I'm still going to modify the part about serial programming/ArduinoISP. I'm also going to try to hook up an old Windows PC to go through everything again to document. I sent the Linux text to KH already, but the simple text is also available on my GitHub page. I don't know if KH will modify the PDF but I tried. It's basically my personal notes from trying to develop a video guide one of these days. ;)

I think your notes will help beginners, as programming the firmware is a typical problem for some. So I don't see any reason why Karl-Heinz shouldn't add your notes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on December 02, 2017, 07:47:17 pm
BTW I have been going through the 'how to program the device on Linux' section of KH's PDF over the last couple of weeks. I rewrote the whole section although I'm still going to modify the part about serial programming/ArduinoISP. I'm also going to try to hook up an old Windows PC to go through everything again to document. I sent the Linux text to KH already, but the simple text is also available on my GitHub page. I don't know if KH will modify the PDF but I tried. It's basically my personal notes from trying to develop a video guide one of these days. ;)

I imagine a step-by-step video of how to identify your particular clone, download the proper firmware for it, and flash it to the tester, would be very useful. Perhaps coverage of the differences between the k and m, to help folks decide which one they want to flash would also be helpful (in the same or separate video).
Title: Re: $20 LCR ESR Transistor checker project
Post by: frozenfrogz on December 02, 2017, 09:10:32 pm
Step-by-step guide would be awesome! My best case scenario however would be something like https://marlinbuilder.robotfuzz.com/ (3D printer marlin firmware builder).

A simple web interface with drop downs for all the options you want to build into the firmware. This could either generate the needed header files or do the complete build and provide the fully compiled files.
Sadly I am a total noob when it comes to this kind of programming...
Title: Re: $20 LCR ESR Transistor checker project
Post by: electricMN on December 03, 2017, 04:19:36 pm
I picked up this board and was wondering what the latest firmware is for it and where can I find it?

https://www.amazon.com/gp/product/B01L706PI2/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 (https://www.amazon.com/gp/product/B01L706PI2/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1)

I've seen the term "strip grid" used in reference to PC boards. What does that mean?

TIA
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on December 03, 2017, 04:46:04 pm
Seems a T4 clone to me, see page 27-28 of the description from Karl-Heinz Kübbeler in the ttester.pdf

SVN:
https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)

Docs:
https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/)

Firmware T3 - T4:
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: electricMN on December 03, 2017, 05:31:39 pm
@Willem52

Thanks, I'll give those files a try.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on December 03, 2017, 09:35:12 pm
I imagine a step-by-step video of how to identify your particular clone, download the proper firmware for it, and flash it to the tester, would be very useful. Perhaps coverage of the differences between the k and m, to help folks decide which one they want to flash would also be helpful (in the same or separate video).
That's what I've been working on for ages ;)
  I put the AY-AT clone on hold, ordered several LCD's and 2 other common clones (GM328-Little-t/T3-T4). Now I have all 3 to compare in hand, plus I have another ATmega328 version on a breadboard, and all the precision components from Mouser to compare everything side by side. I've also tried out etching a couple of weeks ago, ordered an ATmega644 and a bunch of other IC's NickL has used in his versions. I can't say I'll make content on those, but playing with the circuits really helps me understand them better...or at least what color smoke they make.
    Explaining everything visually is challenging. I have to learn this stuff on a whole different level. My goal is to make the content useful for anyone around the World. My video titles and descriptions are poorly translated into 14 languages using G-Translate on YouTube and I don't speak. Hopefully the few English terms used on a schematic are somewhat universal. If anyone notices ways I can improve this feel free to PM me any time or comment through YT.
  I hope to get all 3 clones, a main schematic, and one of Nick L's version 2 schematics all unified on a single layout that is intuitive to understand.  I will probably use a version like the one that is attached below. Suggestions are welcome, and corrections are requested. I'm no expert, just an average dude with too much time on his hands.
-Jake
Title: Re: $20 LCR ESR Transistor checker project
Post by: progrock on December 04, 2017, 02:45:10 am
OK, so, I built this tester... got the AY-AT kit... upgarded the 6 resistors, the Vref, V regulator, and got a 16 Mhz crystal.

I downloaded the 1.30 Markus firmware... un-commented the ST7735 display, ran make (using Ubuntu), and then used an Arduino UNO as a the programmer, and installed the firmware with avrdude.  It sorta works... but when I start it, after a little while it says it's not calibrated, and says I need to start it with the 3 leads connected.  When I do that, it starts in the test mode... but doesn't make it past the first screen (shows the same message saying it needs to be calibrated).  TBH, I have a feeling I didn;t configure the firmware correctly, I'm surprised it even works this much.  I didn't see the correct way to tell it I'm running a 16Mhz crystal... also not sure if the rotary encoder is set up correctly...

Can anyone point me in the right direction on the correct way to build the firmware?.... I'm assuming I have a very common setup based on this thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 04, 2017, 11:45:38 am
If the tester tells you that it's not "calibrated" then you're running the k-firmware. You could try the Makefile from the mega328_color_kit directory and change the clock rate. The m-firmware includes a "Clones" file with settings for the AY-AT kit (also update the MCU clock in the Makefile).
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 04, 2017, 01:19:48 pm
@progrock
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=373958
 :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on December 04, 2017, 05:26:07 pm
@STJ
I have tested the 16Mhz version of the SVN749 AY-AT firmware.
It uses a smaller and fatter font than I was used to with SVN700.
That one was for me much sharper and better to read on the AY-AT.
Also the menu uses only the upper part of the display now...
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 04, 2017, 07:39:14 pm
interesting,
i dont like the font either, but i needed the flash.
maybe i'll try some others.

no idea about the menu size.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 05, 2017, 06:39:28 am
Explanation from Karl-Heinz in the last documentation of 31.10.17 :)
Makefile setting
"MAX MENU LINES This option specifies a maximum count of lines for the shown choices of
menu items. Normally the count of lines for the menu items is given by the present count of
lines of the display. Because there are usually more items selectable as the display can support,
the choices are replaced in a cyclic manner. Building the display content in this cyclic way
will take several time, especially for big color displays with many lines. With the limitation of
the line count by this option you can reduce the output time for the menu choices significant,
which will speed up the operation. The default value for this item is 5.
Example: CFLAGS += -DMAX MENU LINES=3"
Title: Re: $20 LCR ESR Transistor checker project
Post by: aabbcc on December 05, 2017, 03:16:07 pm
Is it possible to test 5 pin transistors with these? Want to check pin configuration (i.e. if its BCECB ) and get an approximate HFE value.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 05, 2017, 07:42:57 pm
Should be possible if you manage to find each transistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MDM3D on December 06, 2017, 06:22:43 am
If you get an AY-AT Clone, the following is a list of hardware corrections to order if you would like to optimize it's operation on M-Firmware. If you normally order parts from Mouser or Digikey all information and links are provided. (No Supplier Affiliation/No Financial Affiliate Program Links) This is simply a resource to make the information easier for the next person to find.
AY-AT Clone - The Proper Mods
1.) 0.1% Probing Resistors
2.) 20mhz Crystal
3.) Correct LDO Vreg
4.) Correct Vref

Manufacturers Part Number=MPN
Mouser Part Number=MoPN
Digikey Part Number=DkPN

(3×)470k Resistors
TE Connectivity
MPN: H8470KBZA
Metal Film Resistors - Through Hole H8 470K 0.1% 100PPM
MoPN: 279-H8470KBZA (http://www.mouser.com/Search/ProductDetail.aspx?R=H8470KBZAvirtualkey50680000virtualkey279-H8470KBZA)
$0.97each (8/2017)
$2.91 (×3)
DkPN: PTF475KCCT-ND (https://www.digikey.com/product-detail/en/te-connectivity-passive-product/H8470KBZA/H8470KBZA-ND/2373532) (not stocked)
Dk Alt:
475k 0.1% 1/8W
Vishay Dale
MPN: PTF56475K00BYEB
DkPN: PTF475KCCT-ND (https://www.digikey.com/product-detail/en/vishay-dale/PTF56475K00BYEB/PTF475KCCT-ND/2273757)
$1.64each (8/2017)

(3×)680ohm Resistors
TE Connectivity
MPN: H8680RBYA
Metal Film Resistors - Through Hole H8 680R 0.1% 15PPM
MoPN: 279-H8680RBYA (http://www.mouser.com/Search/ProductDetail.aspx?R=H8680RBYAvirtualkey50680000virtualkey279-H8680RBYA)
$1.14each (8/2017)
$3.42 (×3)
DkPN: H8680RBYA-ND (https://www.digikey.com/product-detail/en/te-connectivity-passive-product/H8680RBYA/H8680RBYA-ND/2373526)(not stocked)
Dk Alt:
681ohm 0.1% 1/4W
Note: listed as discontinued by digikey (w/available stock 8/2017)
TT Electronics/Welwyn
MPN: RC55Y-681RBI
DkPN: 985-1036-1-ND (https://www.digikey.com/product-detail/en/tt-electronics-welwyn/RC55Y-681RBI/985-1036-1-ND/2401900)
$1.70each (8/2017)

20mhz Crystal
CTS
MPN: ATS20A
Crystals 20MHz 20pF 30ppm -20C 70C
MoPN: 774-ATS20A (http://www.mouser.com/Search/ProductDetail.aspx?R=ATS20Avirtualkey67110000virtualkey774-ATS20A)
$0.36 (8/2017)
DkPN: CTX1106-ND (https://www.digikey.com/product-detail/en/cts-frequency-controls/ATS20A/CTX1106-ND/2640038)
$0.36 (8/2017)

Spare ATmega328
Microchip
MPN: ATMEGA328-PU
8-bit Microcontrollers - MCU AVR 32K FLSH 1K EE2K SRAM-20MHz IND
MoPN: 556-ATMEGA328-PU (http://www.mouser.com/Search/ProductDetail.aspx?R=ATMEGA328-PUvirtualkey55660000virtualkey556-ATMEGA328-PU)
$1.95each (8/2017)
DkPN: ATMEGA328-PU-ND (https://www.digikey.com/products/en?keywords=ATMEGA328-PU)
$1.96each (8/2017)

2.5 Volt 0.1% Precision Reference
Texas Instruments
MPN: LM4040AIZ-2.5/NOPB
Voltage References Prec MicroPwr Shunt Vtg Ref
MoPN: 926-LM4040AIZ25NOPB (http://www.mouser.com/Search/ProductDetail.aspx?R=LM4040AIZ-2.5%2fNOPBvirtualkey59500000virtualkey926-LM4040AIZ25NOPB)
$1.72 (8/2017)
DkPN: LM4040AIZ-2.5/NOPB-ND (https://www.digikey.com/products/en?keywords=LM4040AIZ-2.5%2FNOPB)
$1.73 (8/2017)

5v LDO Voltage Regulator
Microchip
MPN: MCP1702-5002E/TO
LDO Voltage Regulators LDO w/ Low Quiescent
MoPN: 579-MCP1702-5002E/TO (http://www.mouser.com/Search/ProductDetail.aspx?R=MCP1702-5002E%2fTOvirtualkey57940000virtualkey579-MCP1702-5002E%2fTO)
$0.52each (8/2017)
DkPN: MCP1702-5002E/TO-ND (https://www.digikey.com/products/en?keywords=MCP1702-5002E%2FTO)
$0.49each (8/2017)

Total
Mouser: $10.88 (8/2017)
(+USA Econ Shipping@$4.99)
Digikey: $14.56 (8/2017)
(+ Shipping I'm too lazy to look this up)

Mouser USA Part Links Consolidated:
470k Resistors (http://www.mouser.com/Search/ProductDetail.aspx?R=H8470KBZAvirtualkey50680000virtualkey279-H8470KBZA)
680ohm Resistors (http://www.mouser.com/Search/ProductDetail.aspx?R=H8680RBYAvirtualkey50680000virtualkey279-H8680RBYA)
20mhz Crystal (http://www.mouser.com/Search/ProductDetail.aspx?R=ATS20Avirtualkey67110000virtualkey774-ATS20A)
ATmega328 (http://www.mouser.com/Search/ProductDetail.aspx?R=ATMEGA328-PUvirtualkey55660000virtualkey556-ATMEGA328-PU)
LM4040 Vref (http://www.mouser.com/Search/ProductDetail.aspx?R=LM4040AIZ-2.5%2fNOPBvirtualkey59500000virtualkey926-LM4040AIZ25NOPB)
MCP1702 LDO Vreg (http://www.mouser.com/Search/ProductDetail.aspx?R=MCP1702-5002E%2fTOvirtualkey57940000virtualkey579-MCP1702-5002E%2fTO)

I have done all of the hardware upgrades to the ay-at tester unit I have purchased but I am haveing a fairly difficult time building the correct files for the 20MHZ option. If I try to set 20 Mhz in the color kit folder I get an error and can only get it to compile whit 16 mhz option.  But if I use the 1.30m version I don't understand how to change Makefile, config.h or config-<MCU>.h properly with the feature set for the ay-at tester. 

The next question is after I compile these files can I stick the 328p in an uno board and flash the .hex and .eep files while the chip is in the uno or should I rig up the uno as an ISP programmer?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 06, 2017, 08:39:27 am
you cant plug a chip into an uno pcb to program it because it wont have the arduino bootloader on the chip.

you should wire a 6pin header to the pins on the underside of the ay-at chipsocket and then program it "in-circuit"
because that way all the power & crystal etc are already connected.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 06, 2017, 11:32:30 am
I have done all of the hardware upgrades to the ay-at tester unit I have purchased but I am haveing a fairly difficult time building the correct files for the 20MHZ option. If I try to set 20 Mhz in the color kit folder I get an error and can only get it to compile whit 16 mhz option.  But if I use the 1.30m version I don't understand how to change Makefile, config.h or config-<MCU>.h properly with the feature set for the ay-at tester. 

The k-firmware supports up to 16MHz, while the m-firmware goes up to 20MHz. What do you not understand about configuring the m-firmware? The "Clones" file lists the settings for the AY-AT, and in the Makefile set "FREQ = 20".
Title: Re: $20 LCR ESR Transistor checker project
Post by: kimbang on December 06, 2017, 11:38:58 am
Hello Madires,
Could you help me check my case? Please watch the video clip on youtube with the link:  https://youtu.be/Y5Q3kgpF4jw (https://youtu.be/Y5Q3kgpF4jw)
With hardware configuration according to the hardware configuration of the Markus author: Atmega328P, Lcd ST7565R
 I tried so many times with firmware version of Markus V1.30m: I downloaded from: https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)
but failed with includes issues:
+ Always display values BJT NPN 123=CBE hFE 669 regardless of short circuit of all probes.
+ PWM function doesn't work (when i used the oscilloscope to check the output but no value at output )
+ Square Wave function doesn't work (when i used the oscilloscope to check the output but no value at output)
+ Selftest Function doesn't work: I have been waiting for more than 30 minutes but LCD still displayed "Create Short Circuit!"
+ Show Values Function is incorrect
Initially I thought about hardware issues but I have checked my schematic diagram and circuit board very carefully, it's absolutely no problem. I'm sure the bug is from the firmware but I do not know exactly where the error is in source code (I have attached it).
Please help me, thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: blackbird on December 06, 2017, 12:30:35 pm


+ Selftest Function doesn't work: I have been waiting for more than 30 minutes but LCD still displayed "Create Short Circuit!"

You can wait for it to happen until the battery runs out. Or..... you create a short circuit. As the tester is asking you. (Assuming you did not create the short circuit already)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 06, 2017, 12:32:49 pm
Explanation from Karl-Heinz in the last documentation of 31.10.17 :)
Makefile setting
"MAX MENU LINES This option specifies a maximum count of lines for the shown choices of
menu items. Normally the count of lines for the menu items is given by the present count of
lines of the display. Because there are usually more items selectable as the display can support,
the choices are replaced in a cyclic manner. Building the display content in this cyclic way
will take several time, especially for big color displays with many lines. With the limitation of
the line count by this option you can reduce the output time for the menu choices significant,
which will speed up the operation. The default value for this item is 5.
Example: CFLAGS += -DMAX MENU LINES=3"

that's nice, but it's not in the specific makefiles!!
the sourcetree has become a f'ing mess!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: frozenfrogz on December 06, 2017, 01:50:37 pm
you cant plug a chip into an uno pcb to program it because it wont have the arduino bootloader on the chip.

You could however plug the chip in an Uno pcb and use its infrastructure i.e. ISP headers to program the chip via USBtinyISP or similar :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: kimbang on December 06, 2017, 02:07:42 pm


+ Selftest Function doesn't work: I have been waiting for more than 30 minutes but LCD still displayed "Create Short Circuit!"

You can wait for it to happen until the battery runs out. Or..... you create a short circuit. As the tester is asking you. (Assuming you did not create the short circuit already)

When the tester asking create a short circuit, i did the request but nothing happened. I tried to wait for it happen but the screen still displayed the text "Create Short Circuit!"
Title: Re: $20 LCR ESR Transistor checker project
Post by: frozenfrogz on December 06, 2017, 02:18:52 pm
Short 1-2-3 and: push button
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on December 06, 2017, 02:21:51 pm
@STJ
Some example pictures of the SVN 749 AY-AT (STJ) firmware.
To clear things up. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: kimbang on December 06, 2017, 02:29:12 pm
Short 1-2-3 and: push button
I tried but not work
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 06, 2017, 02:35:54 pm
thanks,
i'm going to have to do some serious makefile fixing first.
then this can be fixed - i'm going to test other fonts too - i dont like how bold this one is.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 06, 2017, 02:38:05 pm
you cant plug a chip into an uno pcb to program it because it wont have the arduino bootloader on the chip.

You could however plug the chip in an Uno pcb and use its infrastructure i.e. ISP headers to program the chip via USBtinyISP or similar :)

you could, or you could save the wear on the socket and constant removal of the display if you put the header on the tester.
they should have stuck with smd processors - they all had header pads on them.
i always tell people buying these testers to spend $2 on a USBasp to go with it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kimbang on December 06, 2017, 02:38:43 pm
TO ISSUE A DENIAL: I just tried it again with PWM function and Square Wave function and results:
+ Square Wave function is work well.
+ Square Wave function with something wrong with frequency.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kimbang on December 06, 2017, 02:43:09 pm
I have done all of the hardware upgrades to the ay-at tester unit I have purchased but I am haveing a fairly difficult time building the correct files for the 20MHZ option. If I try to set 20 Mhz in the color kit folder I get an error and can only get it to compile whit 16 mhz option.  But if I use the 1.30m version I don't understand how to change Makefile, config.h or config-<MCU>.h properly with the feature set for the ay-at tester. 

The k-firmware supports up to 16MHz, while the m-firmware goes up to 20MHz. What do you not understand about configuring the m-firmware? The "Clones" file lists the settings for the AY-AT, and in the Makefile set "FREQ = 20".
Hello Madires,
Could you help me check my case? Please watch the video clip on youtube with the link:  https://youtu.be/Y5Q3kgpF4jw (https://youtu.be/Y5Q3kgpF4jw)
With hardware configuration according to the hardware configuration of the Markus author: Atmega328P, Lcd ST7565R
 I tried so many times with firmware version of Markus V1.30m: I downloaded from: https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)
but failed with includes issues:
+ Always display values BJT NPN 123=CBE hFE 669 regardless of short circuit of all probes.
+ PWM function doesn't work (when i used the oscilloscope to check the output but no value at output )
+ Square Wave function doesn't work (when i used the oscilloscope to check the output but no value at output)
+ Selftest Function doesn't work: I have been waiting for more than 30 minutes but LCD still displayed "Create Short Circuit!"
+ Show Values Function is incorrect
Initially I thought about hardware issues but I have checked my schematic diagram and circuit board very carefully, it's absolutely no problem. I'm sure the bug is from the firmware but I do not know exactly where the error is in source code (I have attached it).
Please help me, thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 06, 2017, 02:46:51 pm
Short 1-2-3 and: push button

If you're stuck at "Create short circuit" a short press of the test button will skip the adjustment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kimbang on December 06, 2017, 02:53:41 pm
Short 1-2-3 and: push button

If you're stuck at "Create short circuit" a short press of the test button will skip the adjustment.
I tried to short press the test button but the lcd displayed the tex immediately after that "done!" so it was not calibrated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MDM3D on December 06, 2017, 02:55:18 pm
I have done all of the hardware upgrades to the ay-at tester unit I have purchased but I am haveing a fairly difficult time building the correct files for the 20MHZ option. If I try to set 20 Mhz in the color kit folder I get an error and can only get it to compile whit 16 mhz option.  But if I use the 1.30m version I don't understand how to change Makefile, config.h or config-<MCU>.h properly with the feature set for the ay-at tester. 

The k-firmware supports up to 16MHz, while the m-firmware goes up to 20MHz. What do you not understand about configuring the m-firmware? The "Clones" file lists the settings for the AY-AT, and in the Makefile set "FREQ = 20".

AHA yes that is the info I need in order to configure the software correctly.  Thank you for your patience my Linux/Compiling experience is low outside of Arduino.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 06, 2017, 03:02:01 pm
+ Always display values BJT NPN 123=CBE hFE 669 regardless of short circuit of all probes.
+ PWM function doesn't work (when i used the oscilloscope to check the output but no value at output )
+ Square Wave function doesn't work (when i used the oscilloscope to check the output but no value at output)
+ Selftest Function doesn't work: I have been waiting for more than 30 minutes but LCD still displayed "Create Short Circuit!"
+ Show Values Function is incorrect

That looks like a problem with the probes/test pins. For the ATmega328 it should be PC0-PC2 for probes #1-3, and PB0-PB5 for the test resistors (PB0: 680 Ohms, PB1: 470 kOhms and so on).
Title: Re: $20 LCR ESR Transistor checker project
Post by: kimbang on December 06, 2017, 03:21:18 pm
+ Always display values BJT NPN 123=CBE hFE 669 regardless of short circuit of all probes.
+ PWM function doesn't work (when i used the oscilloscope to check the output but no value at output )
+ Square Wave function doesn't work (when i used the oscilloscope to check the output but no value at output)
+ Selftest Function doesn't work: I have been waiting for more than 30 minutes but LCD still displayed "Create Short Circuit!"
+ Show Values Function is incorrect

That looks like a problem with the probes/test pins. For the ATmega328 it should be PC0-PC2 for probes #1-3, and PB0-PB5 for the test resistors (PB0: 680 Ohms, PB1: 470 kOhms and so on).
Hi there,
I'm sure that I've checked the hardware already, so that is the reason why i think the source code has been changed. Could you please send me the Markus V1.30 firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 06, 2017, 04:05:34 pm
You can download the m-firmware at https://github.com/svn2github/transistortester/tree/master/Software/Markus . Please post some pictures of your PCB (front & back).
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 06, 2017, 04:48:10 pm
thanks,
i'm going to have to do some serious makefile fixing first.
then this can be fixed - i'm going to test other fonts too - i dont like how bold this one is.

just looking through the SVN,
the situation is BULLSHIT.
there are dozens of makefiles - all with different options.
nobody is keeping any of them up to date - i dont even know which is supposed to be the latest.
AND i cant find any damned option to configure menu lines.
i'm out of this until that shit gets cleaned up - i'm not spending hours trying to configure outdated makefiles.  |O
 :rant:
Title: Re: $20 LCR ESR Transistor checker project
Post by: kimbang on December 07, 2017, 01:03:15 am
You can download the m-firmware at https://github.com/svn2github/transistortester/tree/master/Software/Markus . Please post some pictures of your PCB (front & back).

Thanks Madires,
I will redesign a new PCB and i will post here all.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ncclabs on December 07, 2017, 09:11:50 am
I need a file m 1.30 (ST7735), use crystal 16M or 20M, I hope everyone can share :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: kimbang on December 07, 2017, 09:50:14 am
I need a file m 1.30 (ST7735), use crystal 16M or 20M, I hope everyone can share :D
Hello Ncclabs,
Could you share your ComponentTester to my email (bangkimnguyen25@gmail.com)?
My English is not well, so you and me can talk in native language. What's your email address?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ncclabs on December 07, 2017, 03:14:47 pm
I need a file m 1.30 (ST7735), use crystal 16M or 20M, I hope everyone can share :D
Hello Ncclabs,
Could you share your ComponentTester to my email (bangkimnguyen25@gmail.com)?
My English is not well, so you and me can talk in native language. What's your email address?

I sent you a message (gmail)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 08, 2017, 06:18:36 pm
I've got the SSD1306 OLEDs and they are working fine using SPI (4 wire). Next test will be I2C.

Update: I2C works like a charm too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on December 09, 2017, 05:19:20 am
 :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on December 10, 2017, 07:31:54 pm
Not Mastech.  Probably the most useable and practical one out there now.  The tilt display make the meter easier to read.  Left and right button for left and right handed people.  LCD ribbon is not soldered, so burning of new firmware shall be easier.
The other side of PCB shall need to wait.  Desoldering of some thick pins needed and do not look easy :D
I've also bought this meter, branded BSIDE ESR02 Pro on AliExpress:
https://www.aliexpress.com/item/Official-BSIDE-ESR02PRO-Digital-transistor-SMD-Components-tester-Diode-Triode-Capacitance-Inductance-Multimeter-ESR-Meter/32832292103.html (https://www.aliexpress.com/item/Official-BSIDE-ESR02PRO-Digital-transistor-SMD-Components-tester-Diode-Triode-Capacitance-Inductance-Multimeter-ESR-Meter/32832292103.html)

It's really a quite beautiful case and PCB!
It's currently running firmware 1.11k and it was not locked so was possible to save it unlike most others I've seen.

I had an idea to also fit a ATtiny44 SMD PCB inside for easy programming.
It fits great but I realize a problem: it interferes with the sense resistors and thus can't be in circuit while measuring.
So now I'm thinking to find a 5v relay to drive via the USB port too, so it switches the 4 signal wires over. (MOSI, MISO, SCK & Reset)
Currently considering Panasonic S4-5V. Will see how that goes, or anyone have some better solution?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris56000 on December 11, 2017, 08:15:49 pm
Hi!

Can anyone tell me if the full Multicoloured Display Version Firmware (my LCR–T1 leaflet refers to it as "2.12k") used in the Chinese LCR–T1 versions in the white plastic case with the internal LiPo battery and the 50V Sender Test Supply is available separately to re–flash into one of these new Maroon Case Variants, with a colour TFT fitted?

Chris Williams
Title: Re: $20 LCR ESR Transistor checker project
Post by: frozenfrogz on December 11, 2017, 09:23:45 pm
These are technically all derivatives from the original "Transistor Tester". Full source code is available, though some Chinese manufacturers seem to have been doing some changes to the firmware themselves (and do not all disclose the forked source files). While you will need to figure stuff out on your own, the answer to your question is most likely: Yes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MDM3D on December 12, 2017, 03:34:56 am
I have done all of the hardware upgrades to the ay-at tester unit I have purchased but I am haveing a fairly difficult time building the correct files for the 20MHZ option. If I try to set 20 Mhz in the color kit folder I get an error and can only get it to compile whit 16 mhz option.  But if I use the 1.30m version I don't understand how to change Makefile, config.h or config-<MCU>.h properly with the feature set for the ay-at tester. 

The k-firmware supports up to 16MHz, while the m-firmware goes up to 20MHz. What do you not understand about configuring the m-firmware? The "Clones" file lists the settings for the AY-AT, and in the Makefile set "FREQ = 20".

AHA yes that is the info I need in order to configure the software correctly.  Thank you for your patience my Linux/Compiling experience is low outside of Arduino.

Now that I have taken my crash course on getting a hex file to upload via an arduino as an isp is there any reason I should be getting letter(s) that are a different color different than the majority of the text ie. a purple letter or 2 with the majority of the text being green? I am using 1.30m with the 20MHZ option and have completely followed instructions in the clones file to my current understanding. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 12, 2017, 09:22:20 am
Hi!

Can anyone tell me if the full Multicoloured Display Version Firmware (my LCR–T1 leaflet refers to it as "2.12k") used in the Chinese LCR–T1 versions in the white plastic case with the internal LiPo battery and the 50V Sender Test Supply is available separately to re–flash into one of these new Maroon Case Variants, with a colour TFT fitted?

Chris Williams

the correct answer is NO.
Title: Re: $20 LCR ESR Transistor checker project
Post by: frozenfrogz on December 12, 2017, 10:12:07 am
the correct answer is NO.

Why is that?
I thought these are all basically the same. It might involve board modifications though...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 12, 2017, 10:34:16 am
Now that I have taken my crash course on getting a hex file to upload via an arduino as an isp is there any reason I should be getting letter(s) that are a different color different than the majority of the text ie. a purple letter or 2 with the majority of the text being green? I am using 1.30m with the 20MHZ option and have completely followed instructions in the clones file to my current understanding.

Are you talking about SW_PROBE_COLORS? If enabled the pinout of components is color coded (different color for each probe/test pin). Otherwise there could be an interface issue with the LCD. BTW, you can change the colors in colors.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 12, 2017, 01:37:45 pm
the unit he has is very modified - it shows graphics of the socket and all kinds of interesting stuff.
it even draws waveforms from the IR sensor.

i *really* wish the guy who did all that would jump on the forums and share his work.
i think the hardware uses a different mcu to the usual ones too - so working out the pinout/schematic would take a while.

Title: Re: $20 LCR ESR Transistor checker project
Post by: aabbcc on December 12, 2017, 01:44:27 pm
Should be possible if you manage to find each transistor.

Maybe a stupid question, but practically how do I insert it?
(https://i.ytimg.com/vi/oij9JLOIHs0/hqdefault.jpg)

I have a few 2sc2291 that I want to check authenticity by:

* Checking pin orientation
* Measuring hfe

They are 5 pin transistors and the pins should be ECBCE, do I only insert some of the pins, and if so, which ones?
(http://i.imgur.com/saYpsLb.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 12, 2017, 02:37:32 pm
Maybe a stupid question, but practically how do I insert it?

Three short leads with clips/hooks/grabbers?

I have a few 2sc2291 that I want to check authenticity by:

* Checking pin orientation
* Measuring hfe

They are 5 pin transistors and the pins should be ECBCE, do I only insert some of the pins, and if so, which ones?

The first three pins, and then the last three pins. That way you can check both BJTs in the package.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on December 12, 2017, 02:41:40 pm
Should be possible if you manage to find each transistor.

Maybe a stupid question, but practically how do I insert it?
(https://i.ytimg.com/vi/oij9JLOIHs0/hqdefault.jpg)

I have a few 2sc2291 that I want to check authenticity by:

* Checking pin orientation
* Measuring hfe

They are 5 pin transistors and the pins should be ECBCE, do I only insert some of the pins, and if so, which ones?
(http://i.imgur.com/saYpsLb.jpg)
https://www.muffwiggler.com/forum/viewtopic.php?t=14508


Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 12, 2017, 03:09:03 pm
the unit he has is very modified - it shows graphics of the socket and all kinds of interesting stuff.
it even draws waveforms from the IR sensor.

i *really* with the guy who did all that would jump on the forums and share his work.
i think the hardware uses a different mcu to the usual ones too - so working out the pinout/schematic would take a while.

The TC-1 has an ATmega324 and, IIRC, the IR decoder supports only one or two protocols. BTW, I'm working with someone to find the correct settings to run the m-firmware on the TC-1. There will be a small change for the battery management in the next firmware version as a first result. The other tester in the fancy red case has an ATmega328.

We've tried to encourage the clone manufacturers to send samples and firmware modifications, but we haven't received anything yet. It seems they aren't interested in supporting the project they are profiting from. :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 12, 2017, 03:28:33 pm
unfortunate because if they included a bootloader or a second mcu to act as icsp they could sell it as "upgradeable"
Title: Re: $20 LCR ESR Transistor checker project
Post by: MDM3D on December 12, 2017, 09:20:27 pm
Now that I have taken my crash course on getting a hex file to upload via an arduino as an isp is there any reason I should be getting letter(s) that are a different color different than the majority of the text ie. a purple letter or 2 with the majority of the text being green? I am using 1.30m with the 20MHZ option and have completely followed instructions in the clones file to my current understanding.

Are you talking about SW_PROBE_COLORS? If enabled the pinout of components is color coded (different color for each probe/test pin). Otherwise there could be an interface issue with the LCD. BTW, you can change the colors in colors.h.
Nope more like this...(https://uploads.tapatalk-cdn.com/20171212/36889accb23b10731667a3b86b5e6ef1.jpg)(https://uploads.tapatalk-cdn.com/20171212/1bdf698ad1cb99140ccf3394e5e11e55.jpg)

Sent from my SAMSUNG-SM-G900A using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 13, 2017, 11:22:21 am
The 'S' of 'Select:' is also missing. That seems to be an interface problem. You could try to add a small delay in the SPI driver, i.e. SPI_Write_Byte(). Maybe one or two 'wdt_reset();' in the loop to stretch the SPI clock cycle. I think, this is the first time I've seen such a problem with a color display. The ST7735 displays I got are running fine with a 20MHz Atmega328 in bit-bang mode. BTW, with a rotary encoder you can enable SW_PWM_PLUS instead of SW_PWM_SIMPLE.
Title: Re: $20 LCR ESR Transistor checker project
Post by: donbowman on December 14, 2017, 08:56:23 pm
An earlier message talked about a flashing 'Vext=0mV'. I have the same issue, the device powers up, shows the menu, then shows BAT=9.3V, VCC=5V, then shows Bat = 9.3V and flashing Vext=0mV.

This is w/ the AY-AT clone, specifically 2578AY-AT. I can't seem to get it to do anything else, regardless of knob press/turn.
Can someone suggest where to debug? I'm using the schematic from https://github.com/Upcycle-Electronics/AVR-Transistor-Tester/blob/master/AY-AT%20J1.3.pdf

I'm not sure where to look, the voltages look ok from what i can tell, and clearly the cpu is programmed since i can read the lcd.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 15, 2017, 12:06:47 pm
I'd start with checking T2 which is driving PD7.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rwgast_lowlevellogicdesin on December 21, 2017, 10:28:41 pm
Ok usually I read a thread all the way through before I just post, but at 100+ pages.... im sorry if I am asking some questions that have already been answered. A while back a client hired me to fix an audio amplifier and he ordered two of there guys, EBay Special, TC1 Transistor Testor and ESR meterl (https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR0.TRC0.H0.Xtransistor+testor+tc1.TRS0&_nkw=transistor+testor+tc1&_sacat=0), so I could quickly test some of the transistors and the ESR of the caps. Well he liked messing with electronics too but doesnt know much, so one was for him. He blew his out in the first hour, I had assumed testing a charged cap.. I took it apart gave it a quick look and just assumed the avr got friend with out much testing.

Well now mine is having the same problem as his after months of steady use, I was testing a small 10v 470uf cap (I had shorted the caps leads on piece of copper, I tested it once no problem, then hit test again the middle of the second test killed it) right after fully charging the units lithium battery and all the sudden the screen went black and the test button failed to do anything. This had happened to me a few times before but all the other times this has happened all I had to do was hold the test button down for about 30 seconds and then press it again, im assuming this just fully turns of the micro and resets the board. This time that trick did not work for me, this is the same exact problem with the first tester that blew up.

I opened the case disconnected the battery and charged it on a separate charger, didn't resolve anything. I read through the PDF file for these last night and found out just how versatile these things are! I also found the trouble shooting section and now I believe there is something wrong with the power system from what I read. This unit also has a boost converter and transformer, for testing LED's and Zeners i am guessing. It is putting out about 15 volts but the chip AL605 gets extremely hot to the touch, I also could not find a 5 volt rail anywhere on the board, the linear regulator was only putting out like 2.5v or something, if I recall correctly. I tested the bus lines on the screen to make sure the screen wasnt just broken, and there is no data on the lines when I press test.

I just printed out the base tester schematic (published in the pdf file, transistor tester plus a little more) and the pinout of the Atmega32PA4 (this is the AVR this clone uses) and plan to take more trouble shooting steps a bit later today. So I guess here are my questions,

#1 Is there a known common problem with the TC1 version tester that matches the problem I have described, If not what is anyone elses take on what happend and whats wrong with it. I dont think the charge from the first test is enough to blow the micro out when testing a second time.

#2 Is there open, upgraded and modifiable firmware for this TC1 model, that work if I were to add the ISP header. I had always assumed no until I did a bit more reading in to these things. This is especially necessary if I have to replace the avr chip, or at least a hex file and fuse settings.

#3 My unit has the screen soldered in with headers, when the original broke I de-soldered the lcd and saved it for whatever reason, can anyone tell me exactly what display driver chip these use?

#4 Lastly if I were to just replace  this one or buy a second, what is the most hardware/software hack-able model, Ive seen the "new 2017" version but id like to get one with a color LCD to start off with. I guess im looking for one with a nice screen I can add all the options too.

If you havent see this document is really good it is version 1.13, the older versions dont contain near the amount of info, it talks about different LCD driver choices using a mega etc etc
http://www.avrtester.tode.cz/upload/ttester_en.pdf (http://www.avrtester.tode.cz/upload/ttester_en.pdf)

*Edit* I forgot one thing, I know these arent the best ESR testers but they do the job, does anyone know how if the DIY 5 transistor tester allen posted works better for esr?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 22, 2017, 03:23:00 am
if the 5v regulator is outputting 2.5 then what's on it's input??
maybe the boost circuit is bad so your only getting the 3.7v from the battery.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rwgast_lowlevellogicdesin on December 22, 2017, 07:14:53 am
Ok so I took some time with a meter and scope to try to track down the problem, and it either the boost converter to run the 5v regulator, the inductor/transformer, or the rectifier diode between the regulator input and inductor. for some reason the input to the 5v ldo is only 2.5v and 1.8v between the inductor and diode, while the 15v boost for diode testing works just fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 22, 2017, 11:57:04 am
#1 Is there a known common problem with the TC1 version tester that matches the problem I have described, If not what is anyone elses take on what happend and whats wrong with it. I dont think the charge from the first test is enough to blow the micro out when testing a second time.

Since you already know that the power supply circuitry has a problem, I'd like to add that the TC1 uses a poor pin assignment for the ATmege324. Hardware SPI isn't possible because two pins are swapped. And OC1B isn't connected at all, i.e. no signal output (PWM/squarewave/...). BTW, the next m-firmware version will support a dedicated signal output via OC1B, when that pin isn't used for the 680 Ohms probe resistor for testpin/probe #2.

#2 Is there open, upgraded and modifiable firmware for this TC1 model, that work if I were to add the ISP header. I had always assumed no until I did a bit more reading in to these things. This is especially necessary if I have to replace the avr chip, or at least a hex file and fuse settings.

k and m-firmware ;)

#3 My unit has the screen soldered in with headers, when the original broke I de-soldered the lcd and saved it for whatever reason, can anyone tell me exactly what display driver chip these use?

AFAIK, they come with different displays. Monochrome could be ST7565.

#4 Lastly if I were to just replace  this one or buy a second, what is the most hardware/software hack-able model, Ive seen the "new 2017" version but id like to get one with a color LCD to start off with. I guess im looking for one with a nice screen I can add all the options too.

That would be the AY-AT kit with a ST7735 and rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 22, 2017, 09:36:13 pm
Changes for v1.31m:
- New tool: IR RC transmitter.
- Added support for dedicated signal output via OC1B, when OC1B isn't used for test pin #2's probe resistor.
- Changed battery monitoring settings to support also other power options.
- Driver for SSD1306 based graphic OLED modules.
- Color support for item selection (menues and tools).
- Driver for ILI9163 based graphic color LCD modules.
- Fixed tiny issue in squarewave signal generator.
- Added support for 180° rotated output to PCD8544 LCD driver.
- Fixed edit error in Servo_Check().

The IR RC supports following protocols at the moment:
- NEC standard & extended
- Samsung/Toshiba (32 bits)
- Sony SIRC 12, 15 and 20 bits

More protocols to come...
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on December 22, 2017, 10:44:20 pm
Changes for v1.31m:
- New tool: IR RC transmitter.

Ah, so you can change the channel while checking ESR on old gear for repair. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on December 24, 2017, 07:58:31 am
n00b alert!

Hi everyone, let me start by saying thanks to Dave and all the contributors to this particular project. Vielen danke!
So I'm a guitar player, a pretty bad one at that, LOL but anyway. I came across Antigua's wonderful work here http://guitarnuts2.proboards.com/thread/7723/measuring-electrical-properties-guitar-pickups (http://guitarnuts2.proboards.com/thread/7723/measuring-electrical-properties-guitar-pickups) where he explains the electronic properties of guitar pickups and how to test them. Most of that goes well over my head, but apparently being able to measure guitar pickups' inductance (and capacitance?) provides some useful information about their theoretical frequency response.

So we've ordered these TCR-T4's and wondering if they can be used or the firmware can be modified to accomplish our goal? I'm a software guy and I'm more than willing to get my hands dirty
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on December 24, 2017, 08:23:42 am
Please see message reply #4242

https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1365473/#msg1365473
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on December 24, 2017, 09:33:15 am
So according to the manual, inductance measurement runs for resistance values under 2K1R if I got that right.
Guitar pickups are typically above 5KR and inductance of several H's (2H, 4H etc..)

Does that mean that this device will not be capable of reading pickup inductance? Here's the one I ordered https://www.ebay.es/itm/112527481729 (https://www.ebay.es/itm/112527481729)
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 24, 2017, 10:46:04 am
why not just play some chords on it and capture it on a pc.
then you can see the frequencys  in some audio editing software
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on December 24, 2017, 10:53:36 am
why not just play some chords on it and capture it on a pc.
then you can see the frequencys  in some audio editing software

My uneducated guess is that would introduce too many factors to make the test meaningful: pickup position, string type and wear, picking technique, saddle material, tonewood... 
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 24, 2017, 12:42:02 pm
So according to the manual, inductance measurement runs for resistance values under 2K1R if I got that right.
Guitar pickups are typically above 5KR and inductance of several H's (2H, 4H etc..)

Does that mean that this device will not be capable of reading pickup inductance? Here's the one I ordered https://www.ebay.es/itm/112527481729 (https://www.ebay.es/itm/112527481729)

Yep, it won't try to measure the inductance when the resistance is larger then 2k. For those kind of measurements I'd suggest to get a proper LCR meter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on December 24, 2017, 01:09:07 pm
So according to the manual, inductance measurement runs for resistance values under 2K1R if I got that right.
Guitar pickups are typically above 5KR and inductance of several H's (2H, 4H etc..)

Does that mean that this device will not be capable of reading pickup inductance? Here's the one I ordered https://www.ebay.es/itm/112527481729 (https://www.ebay.es/itm/112527481729)

Yep, it won't try to measure the inductance when the resistance is larger then 2k. For those kind of measurements I'd suggest to get a proper LCR meter.

Thank you madires.

How about this "sampling ADC" method described in section 3.10 of the manual?

With the samplingADC method a resonant frequency
of coils can be detected with greater inductance values. If this effect is noticeable, the frequency and
the quality factor Q of the coil is shown additionally in line 3.
The method of resonant frequency measurement can also be used for the determination of the
inductance value, if a sufficient big capacitor mith know capacity value is connected parallel to a little
inductance (<2mH). With a parallel connected capacitor the normal measurement of inductance
can no more operate well. If the resonant frequency let assume a parallel connected capacitor, the
inductance of the normal measurement is not shown and the resistance value is shown in line 1. For
this resonant circuit the quality factor Q is also computed and shown behind the frequency value in
line 3. You can identify this type of measurement with the inductance value at the first position of
line 2, followed by the text ” if ” and the value of the assumed parallel capacity. The value of this
3 10 ? 30nF (L)).
parallel capacitor can currently only be set with the calibration function (1
For displays with only two lines, the content for the third line is shown time-delayed in line 2.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 25, 2017, 01:26:03 pm
The k-firmware's sampling ADC might work. I haven't tried it with large inductance values yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on December 25, 2017, 02:10:28 pm
The k-firmware's sampling ADC might work. I haven't tried it with large inductance values yet.

Great! I'll need to flash this .eep & .hex files, right?

ETA: this programmer would work? https://www.ebay.es/itm/LC-01-51-AVR-Programmer-ISP-USBASP-Downloader-USBISP-Download-Line/152706097159?hash=item238dfe2007:g:W7MAAOSwVfxZvWuz (https://www.ebay.es/itm/LC-01-51-AVR-Programmer-ISP-USBASP-Downloader-USBISP-Download-Line/152706097159?hash=item238dfe2007:g:W7MAAOSwVfxZvWuz)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 25, 2017, 04:34:48 pm
Yes & yes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on December 25, 2017, 05:56:35 pm
Does anybody know what firmware these T4's come with?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 26, 2017, 11:50:11 am
AFAIK, they run a modified k-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on December 26, 2017, 12:20:55 pm
It's really a quite beautiful case and PCB!
It's currently running firmware 1.11k and it was not locked so was possible to save it unlike most others I've seen.

I had an idea to also fit a ATtiny44 SMD PCB inside for easy programming.
It fits great but I realize a problem: it interferes with the sense resistors and thus can't be in circuit while measuring.
So now I'm thinking to find a 5v relay to drive via the USB port too, so it switches the 4 signal wires over. (MOSI, MISO, SCK & Reset)
Currently considering Panasonic S4-5V. Will see how that goes, or anyone have some better solution?

By any chance you have captured the firmware?  First time I blew one of these.  The socket clips make capacitor testing so easy.  I picked up a big capacitor from my storage to try to confirm something, and blew my set after I had it for a few days.   Too easy to use, a bit too easy to blow 😉
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on December 28, 2017, 12:32:20 pm
Yes of course, here you go.
Just one caveat to be aware of: it contains the calibration data from my meter.
So you should make a new calibration even though you will have no message telling you it's not calibrated....
And the fuses where set according to the picture included.
Title: Re: $20 LCR ESR Transistor checker project
Post by: cvanc on December 28, 2017, 04:22:56 pm
Hi all-

I want to buy an assembled, ready to use tester, hopefully with a color screen.  Ideally I could find a source here in the U.S.  Is there a model or models that are currently considered "the good ones"?

Also, can anyone explain the difference between this 'B1' and 'B2' version?  (and... is this a decent meter in either version?)

https://www.ebay.com/itm/B1-Color-1-8-TFT-ESR-Meter-Transistor-Resistor-Diode-Triode-Capacitor-Tester/322869859401?hash=item4b2c8b1449:g:jkEAAOSwU1FaAlx0 (https://www.ebay.com/itm/B1-Color-1-8-TFT-ESR-Meter-Transistor-Resistor-Diode-Triode-Capacitor-Tester/322869859401?hash=item4b2c8b1449:g:jkEAAOSwU1FaAlx0)

https://www.ebay.com/itm/B2-Color-1-8-TFT-ESR-Transistor-Resistor-Diode-Capacitor-Mosfet-Tester/232448188853?hash=item361efde1b5:g:~RIAAOSweNxZkd8h (https://www.ebay.com/itm/B2-Color-1-8-TFT-ESR-Transistor-Resistor-Diode-Capacitor-Mosfet-Tester/232448188853?hash=item361efde1b5:g:~RIAAOSweNxZkd8h)

Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rhb on December 28, 2017, 04:37:50 pm
I've not read this thread much.  As Dave noted, tl;dr.  I *am* quite interested though.

I just sent an email proposing to EEVblog that a wiki be set up where the generally useful content of threads like this can be more easily accessed.  If you think this would be a good idea, please comment here:

https://www.eevblog.com/forum/suggestions/equipment-wikis/ (https://www.eevblog.com/forum/suggestions/equipment-wikis/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on December 28, 2017, 07:13:31 pm
Hello everyone

I would like to replace TL431A to TL431B to get better accuracy measurement in  "AY-AT" but I can not find TL431B. I found TL431ZCLS IK-SEMICON. Will it be good? Do I have to also  replace something else to get it worked?
Here is the reference.

https://www.maritex.com.pl/product/attachment/35707/TL431Z_03.pdf (https://www.maritex.com.pl/product/attachment/35707/TL431Z_03.pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 28, 2017, 08:15:39 pm
I want to buy an assembled, ready to use tester, hopefully with a color screen.  Ideally I could find a source here in the U.S.  Is there a model or models that are currently considered "the good ones"?

Also, can anyone explain the difference between this 'B1' and 'B2' version?  (and... is this a decent meter in either version?)

I'd go for an assembled AY-AT. The tester you've mentioned is a simple one running a modified firmware. The only difference between the the two models seems to be the color of the case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 28, 2017, 08:19:01 pm
I would like to replace TL431A to TL431B to get better accuracy measurement in  "AY-AT" but I can not find TL431B. I found TL431ZCLS IK-SEMICON. Will it be good? Do I have to also  replace something else to get it worked?

It's a 0.5% type. You just need to replace the TL431. That's all to be done.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 28, 2017, 08:21:50 pm
I've not read this thread much.  As Dave noted, tl;dr.  I *am* quite interested though.

I just sent an email proposing to EEVblog that a wiki be set up where the generally useful content of threads like this can be more easily accessed.  If you think this would be a good idea, please comment here:

https://www.eevblog.com/forum/suggestions/equipment-wikis/ (https://www.eevblog.com/forum/suggestions/equipment-wikis/)

Jake (jakeisprobably) is working on something similar already, just for the Transistor Tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 28, 2017, 10:56:22 pm
Hello everyone

I would like to replace TL431A to TL431B to get better accuracy measurement in  "AY-AT" but I can not find TL431B. I found TL431ZCLS IK-SEMICON. Will it be good? Do I have to also  replace something else to get it worked?
Here is the reference.

https://www.maritex.com.pl/product/attachment/35707/TL431Z_03.pdf (https://www.maritex.com.pl/product/attachment/35707/TL431Z_03.pdf)


forget that, use an LM4040
Title: Re: $20 LCR ESR Transistor checker project
Post by: Seabird on December 29, 2017, 04:15:04 am
I hope that I am not hijacking this thread (apologies in advance if I am)!  I have just purchased a LC-T3-H which has a very similar board layout to this schematic published earlier in this thread.  Somehow, I inadvertently got into the contrast setting and stupidly kept pressing the button in the hopes it would roll over and I would regain a readable display - Duh!  With the blank screen I now have no way of knowing what I am doing.  My questions are:  is there a 'factory reset' sequence I could use?  Are there a series of key strokes that somebody could provide to decrease the contrast setting (knowing that I would be doing this blind)?  Another thought I had was to physically wire the contrast pin of the LCD to a potentiometer to manual adjust while I get things back to normal but I am not sure which is the correct pin on the LCD?  Of course, any other suggestions that would help me get out of this dilemma will be appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 29, 2017, 06:12:09 am
Seabird
In this firmware the contrast range is regulated programmatically. It is necessary for you it is long to press the Test button, then short clicking to change contrast range. Only 10 options of level of contrast range.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on December 29, 2017, 08:56:04 am
It's really a quite beautiful case and PCB!
It's currently running firmware 1.11k and it was not locked so was possible to save it unlike most others I've seen.

I had an idea to also fit a ATtiny44 SMD PCB inside for easy programming.
It fits great but I realize a problem: it interferes with the sense resistors and thus can't be in circuit while measuring.
So now I'm thinking to find a 5v relay to drive via the USB port too, so it switches the 4 signal wires over. (MOSI, MISO, SCK & Reset)
Currently considering Panasonic S4-5V. Will see how that goes, or anyone have some better solution?

Thank you for your firmware.  I have recovered my set.  I tried to program in-circuit by adding header pins for the MOSI, MISO and SCK signal which sit nicely on the R18, R19 and R20 respectively.  I just tap the Vcc from J6.V, Gnd from J6.G, and reset from J6.R.  But this did not work, with or without R18, R19 and R20 in, and with the LCD ribbon out.  I am not sure what is the problem.
 

Title: Re: $20 LCR ESR Transistor checker project
Post by: Seabird on December 29, 2017, 10:13:49 am
Thank you Indman.  That worked a treat.  Much appreciated as I thought I would have to buy another unit (and be more careful)!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on December 30, 2017, 11:43:34 am
Thank you for your firmware.  I have recovered my set.  I tried to program in-circuit by adding header pins for the MOSI, MISO and SCK signal which sit nicely on the R18, R19 and R20 respectively.  I just tap the Vcc from J6.V, Gnd from J6.G, and reset from J6.R.  But this did not work, with or without R18, R19 and R20 in, and with the LCD ribbon out.  I am not sure what is the problem.
Strange, I did something very similar to read it out in circuit:
Cables tapped into R18, R19 & R20, I took reset at R2 closest to the Atmega, but I see you are correct that it's a direct connection to that J6-R point.
But then I used power on device: so I wired up ground to the battery ground and powered on the meter with it's own test button...

Later I also tried it with the small ATtiny44 PCB, the problem I have is that it can't be in circuit, so need to switch it out with a relay or mechanical switch.
That worked too with the caveat as described...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Lenny on December 30, 2017, 07:14:45 pm
I have uploaded the newest "Markus Firmware". Everything works fine...

But where can I see if the reference voltage is used - I have retrofittet an LM4040 and would like to know if it works.

Is it possible to stop refreshing after a proper value is read?

The tester is a very useful tool... thanks to the developers!

Lenny
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 30, 2017, 07:48:05 pm
Select "show values" in the main menu to display the adjustment values and check if Vcc has changed. There's no dedicated indication that the external reference is used. Have you enabled HW_REF25 in config.h?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Lenny on December 31, 2017, 06:25:04 pm
Thanks for the quick respone, I will try the days - the settinngs I have made.

Do you know by chance where this is descriped with the repetitions?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 01, 2018, 02:18:12 pm
Do you mean the auto-hold mode? Start the tester with a long key press (>300ms).
Title: Re: $20 LCR ESR Transistor checker project
Post by: rwgast_lowlevellogicdesin on January 01, 2018, 09:46:27 pm
Ok I replaced my blown up TC1 with an AY YT kit with color LCD. I seem to be having some subtle problems and Im not sure if there normal.

#1 The display always says my battery is weak @7.3v or lower even with a brand new 9 volt battery. I measured the vRef at 2.493 which seems normal enough, but the voltage regulator is putting out like 5.8v or something near that.. could that have something to do with why the tester thinks the 9v is always low?

#2 The LCD background is flickering, like there are white refresh lines moving around, no amount of re-flowing the cheap LCD module helped. It is only the background that flickers though not the foreground text, could this just be an issue with the 8mhz crystal?

#3 The tester reports the ESR of every cap at 0.00, unless it is an extremely bad cap which has an ESR of multiple ohms.

Lastly where do I find the newest trendy firm ware hex and fuse settings? I looked through a link to an SVN mentioned in this thread but the newest version didnt seem to match up with the version # posted in this thread and I still have no idea what fuse settings I need to use.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on January 02, 2018, 08:45:22 am
The output of the LDO (voltage regulator) is too high!
All problems could be related just to that fact.

The output is expected to be like 4.95 - 5.05 VDC.

The fuses:
lfuse: 0xf7   hfuse: 0xd9   efuse: 0x04
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on January 02, 2018, 02:47:17 pm
In the readme with software 1.31m it is witten

The external 2.5V voltage reference should be only enabled if it's at least
10 times more precise than the voltage regulator. Otherwise it would make
the results worse. If you're using a MCP1702 with a typical tolerance of
0.4% as voltage regulator you really don't need a 2.5V voltage reference.


Does it mean that if I change voltage regulator to MCP1702-5002E/TO  (0,4%) then I shuldn't change reference voltage to any with 0,1% precision ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 02, 2018, 03:33:47 pm
Yep, with a MCP1702-5002 you don't need any external voltage reference, unless you happen to have one with a tolerance of <= 0.05%. ;) It would make more sense to measure the output voltage of the LDO with a 6-1/2 digit (or better) DMM and change UREF_VCC in config.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on January 02, 2018, 03:55:16 pm
 So, what to do better - change voltage regulator to 0,4% or reference voltage to 0,1% ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 02, 2018, 08:07:57 pm
I'd go for the 0.4% voltage regulator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on January 03, 2018, 08:09:31 am
What do people use to program a 2017 2578ay-at? Remove the Atmega328p and program it separately (which would be easy enough, but removing the 28DIP Atmega frequently risks causing problems)? Or would connecting to R3-1 (RST), R10-17 (MOSI), R11-18 (MISO), R12-19 (SCK) and VCC/GND work in circuit? If the latter, do you power the Atmega thru the USBASP connector, or connect GND and use a separate power for the AY AT?

Since the kit uses thru-the-hole components, putting a clip in the right resistor leg should work fine, and I wouldn't need to solder a more permanent ISP

I have programmed all types of Atmega328p both in circuit and standalone, just wondering what's the best option for this particular board (since I'm not sure how the other components could influence the in-circuit flashing)

Thanks in advance (and thanks to all the info provided in the thread, which I just finished reading start to end...)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on January 03, 2018, 01:37:41 pm
I'd go for the 0.4% voltage regulator.

So if I mount 0,4% voltage regulator and leave chinese TL431 then I must disable the external reference by removing it or undefining HW_REF25 to get better results?

Thank you for help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 03, 2018, 03:01:27 pm
Exactly! Either comment out "HW_REF25" or remove the reference. And for the k-firmware one would have to remove or comment out the check of the external reference in the source code, or physically remove the reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 03, 2018, 03:07:24 pm
What do people use to program a 2017 2578ay-at? Remove the Atmega328p and program it separately (which would be easy enough, but removing the 28DIP Atmega frequently risks causing problems)? Or would connecting to R3-1 (RST), R10-17 (MOSI), R11-18 (MISO), R12-19 (SCK) and VCC/GND work in circuit? If the latter, do you power the Atmega thru the USBASP connector, or connect GND and use a separate power for the AY AT?

Some simply pull the ATmega, some add a 6-pin ISP header. Do whatever you prefer. The 5V from the programmer are sufficient for programming.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on January 03, 2018, 06:50:44 pm
For all beginners simpliest way is serial port programming with only 3 resistors and one jumper for reset pin, copy downloaded files in root c:\ (TransistorTester.hex and TransistorTester.eep ) I`m soldered pin header  from downside direct on atmega pins and program in three seconds .

In avrdude.conf change inverted reset to non-inverted

reset = 3

and with next 3 comands programm atmega

avrdude -p ATMEGA328P -c ponyser -P COM1  -U flash:w:"C:\TransistorTester.hex":i

avrdude -p ATMEGA328P -c ponyser -P COM1  -U eeprom:w:"C:\TransistorTester.eep":i

avrdude -p ATMEGA328P -c ponyser -P COM1 -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

Fusebits are for default 8Mhz version.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=243066;image)
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=243068;image)

How the reset should be connected to serial port??? On the photo I can se the closed jumper, where it shuld be connected? There are already 5 pins MOSI, MISO, SCK, AVCC and GND which are connected to serial port.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on January 03, 2018, 11:53:29 pm
If you get an AY-AT Clone, the following is a list of hardware corrections to order if you would like to optimize it's operation on M-Firmware. If you normally order parts from Mouser or Digikey all information and links are provided. (No Supplier Affiliation/No Financial Affiliate Program Links) This is simply a resource to make the information easier for the next person to find.
AY-AT Clone - The Proper Mods
1.) 0.1% Probing Resistors
2.) 20mhz Crystal
3.) Correct LDO Vreg
4.) Correct Vref

Manufacturers Part Number=MPN
Mouser Part Number=MoPN
Digikey Part Number=DkPN

(3×)470k Resistors
TE Connectivity
MPN: H8470KBZA
Metal Film Resistors - Through Hole H8 470K 0.1% 100PPM
MoPN: 279-H8470KBZA (http://www.mouser.com/Search/ProductDetail.aspx?R=H8470KBZAvirtualkey50680000virtualkey279-H8470KBZA)
$0.97each (8/2017)
$2.91 (×3)
DkPN: PTF475KCCT-ND (https://www.digikey.com/product-detail/en/te-connectivity-passive-product/H8470KBZA/H8470KBZA-ND/2373532) (not stocked)
Dk Alt:
475k 0.1% 1/8W
Vishay Dale
MPN: PTF56475K00BYEB
DkPN: PTF475KCCT-ND (https://www.digikey.com/product-detail/en/vishay-dale/PTF56475K00BYEB/PTF475KCCT-ND/2273757)
$1.64each (8/2017)

(3×)680ohm Resistors
TE Connectivity
MPN: H8680RBYA
Metal Film Resistors - Through Hole H8 680R 0.1% 15PPM
MoPN: 279-H8680RBYA (http://www.mouser.com/Search/ProductDetail.aspx?R=H8680RBYAvirtualkey50680000virtualkey279-H8680RBYA)
$1.14each (8/2017)
$3.42 (×3)
DkPN: H8680RBYA-ND (https://www.digikey.com/product-detail/en/te-connectivity-passive-product/H8680RBYA/H8680RBYA-ND/2373526)(not stocked)
Dk Alt:
681ohm 0.1% 1/4W
Note: listed as discontinued by digikey (w/available stock 8/2017)
TT Electronics/Welwyn
MPN: RC55Y-681RBI
DkPN: 985-1036-1-ND (https://www.digikey.com/product-detail/en/tt-electronics-welwyn/RC55Y-681RBI/985-1036-1-ND/2401900)
$1.70each (8/2017)

[...]

2.5 Volt 0.1% Precision Reference
Texas Instruments
MPN: LM4040AIZ-2.5/NOPB
Voltage References Prec MicroPwr Shunt Vtg Ref
MoPN: 926-LM4040AIZ25NOPB (http://www.mouser.com/Search/ProductDetail.aspx?R=LM4040AIZ-2.5%2fNOPBvirtualkey59500000virtualkey926-LM4040AIZ25NOPB)
$1.72 (8/2017)
DkPN: LM4040AIZ-2.5/NOPB-ND (https://www.digikey.com/products/en?keywords=LM4040AIZ-2.5%2FNOPB)
$1.73 (8/2017)

5v LDO Voltage Regulator
Microchip
MPN: MCP1702-5002E/TO
LDO Voltage Regulators LDO w/ Low Quiescent
MoPN: 579-MCP1702-5002E/TO (http://www.mouser.com/Search/ProductDetail.aspx?R=MCP1702-5002E%2fTOvirtualkey57940000virtualkey579-MCP1702-5002E%2fTO)
$0.52each (8/2017)
DkPN: MCP1702-5002E/TO-ND (https://www.digikey.com/products/en?keywords=MCP1702-5002E%2FTO)
$0.49each (8/2017)

Total
Mouser: $10.88 (8/2017)
(+USA Econ Shipping@$4.99)
Digikey: $14.56 (8/2017)
(+ Shipping I'm too lazy to look this up)

First of all, thanks for putting this list together, really awesome

I'm a cheapskate (I think that spending ~$14+shipping to improve a ~$10 tester kinda defeats the purpose  :P)

So I tried looking for cheaper alternatives to the components you suggest ordering via Digikey, which has much cheaper shipping for small orders (usually $3.39 USPS first class in the USA)

I plan to get the 16MHz crystal and Atmega via eBay ($1.8 for the Atmega and $0.79 for the 10 crystals... I decided to go with 16MHz, btw, since I won't need the higher frequency and I know aht 16MHz is rock solid even for marginal parts). But getting those thru Digikey would make no real difference

I then looked for resistors similar in value to the default ones, but cheaper than the ~$1.7 each for the ideal match. I have read many times that matching the resistors is more important than the absolute value, so I was thinking about

750 Ohm instead of 680 Ohm (quite a lot, 10% difference, but all 3 resistors would be closely matched)
https://www.digikey.com/product-detail/en/yageo/MFP-25BRD52-750R/750ADCT-ND/2059145 (https://www.digikey.com/product-detail/en/yageo/MFP-25BRD52-750R/750ADCT-ND/2059145)

499k Ohm instead of 470k (this one is close enough, methinks),
https://www.digikey.com/products/en?keywords=A105891CT-ND (https://www.digikey.com/products/en?keywords=A105891CT-ND)

Plus the LDO and reference voltage:
https://www.digikey.com/products/en?keywords=LM4040AIZ-2.5%2FNOPB-ND (https://www.digikey.com/products/en?keywords=LM4040AIZ-2.5%2FNOPB-ND)
https://www.digikey.com/products/en?keywords=MCP1702-5002E%2FTO-ND (https://www.digikey.com/products/en?keywords=MCP1702-5002E%2FTO-ND)

That would bring the total to $5.84 + $3.39 shipping and another ~$2 for the Atmega and crystal(s)

Would it impact the measurements if I used 750 Ohm 0.1% resistors instead of 680 Ohm, and 499K Ohm 0.1% instead of 470k Ohm? Those cost significantly less than the closer matching ones

Title: Re: $20 LCR ESR Transistor checker project
Post by: rwgast_lowlevellogicdesin on January 05, 2018, 12:17:04 am
Ok so im adding a ti .05% 2.5vref to my AY YT along with better resistors and a 16mhz crystal. Is a 20mhz possible with the make file? Anyways Looking through the manual at all the config options when building the firmware my mind is blown, especially at all the LCD stuff... im not even sure if I have an ST or IL LCD or how to tell the difference all I know is i have some spi screens with and without the 4050 buffer... Is there a good way to easily test exactly which driver chip each lcd I have is using (Some are from the TC-1 testers)? Also is there anyway possible to get a default config file for each tester variant as a reference for the default options in there firmware?

One reason I want to move to a higher crystal speed is from the manual it sounds like the inductance measurement resolution will go down but I will be able to measure smaller inductors in turn, is this correct? Right now my AY-AT is not able to measure under 22mH while the TC-1 measured well in to the uH range.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on January 05, 2018, 08:35:41 am
Just tested my 8MHz (k 1.12 firmware mod.) AY-AT tester and it measures a 47 uH as 0.05mH (last digit +/-1)
and my 16MHz (k 1.12 firmware mod.) AY-AT tester and it measures a 47 uH as 0.04mH (last digit +/-1)

So it seems to me that your AY-AT should do that too, there must be something wrong there.

The M-firmware can do till 20MHz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 05, 2018, 11:04:39 am
If you want to measure low value inductances the k-firmware's SamplingADC would be the better option. The m-firmware includes a file named "Clones" which lists the settings for a few clones.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rwgast_lowlevellogicdesin on January 05, 2018, 05:15:45 pm
Maybe I am doing something wrong, I am using sampling mode. I have to connect to pins 1 and 3 or it doesnt test inductance at all, using pins 1 and 3 it first tests resistance and then it tests inductance, with anything under 22mH it just blinks the inductance test and then reports the resistance only. What could cause this issue?

I still want to upgrade to a 16mhz xtal no matter if thats the problem with the inductance or not, the thing is just to slow with a color screen.. so what is the best way to figure out any of the config options im unsure about when it comes to specific hardware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 05, 2018, 05:22:16 pm
A missing cap ;) Please read Karl-Heinz' excellent documentation https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on January 07, 2018, 09:05:01 pm
So I tried looking for cheaper alternatives to the components you suggest ordering via Digikey, which has much cheaper shipping for small orders (usually $3.39 USPS first class in the USA)

[...]

I then looked for resistors similar in value to the default ones, but cheaper than the ~$1.7 each for the ideal match. I have read many times that matching the resistors is more important than the absolute value, so I was thinking about

750 Ohm instead of 680 Ohm (quite a lot, 10% difference, but all 3 resistors would be closely matched)
https://www.digikey.com/product-detail/en/yageo/MFP-25BRD52-750R/750ADCT-ND/2059145 (https://www.digikey.com/product-detail/en/yageo/MFP-25BRD52-750R/750ADCT-ND/2059145)

499k Ohm instead of 470k (this one is close enough, methinks),
https://www.digikey.com/products/en?keywords=A105891CT-ND (https://www.digikey.com/products/en?keywords=A105891CT-ND)

Plus the LDO and reference voltage:
https://www.digikey.com/products/en?keywords=LM4040AIZ-2.5%2FNOPB-ND (https://www.digikey.com/products/en?keywords=LM4040AIZ-2.5%2FNOPB-ND)
https://www.digikey.com/products/en?keywords=MCP1702-5002E%2FTO-ND (https://www.digikey.com/products/en?keywords=MCP1702-5002E%2FTO-ND)

That would bring the total to $5.84 + $3.39 shipping and another ~$2 for the Atmega and crystal(s)

Would it impact the measurements if I used 750 Ohm 0.1% resistors instead of 680 Ohm, and 499K Ohm 0.1% instead of 470k Ohm? Those cost significantly less than the closer matching ones

Re-asking my question, hoping someone (Markus? :)) knows the answer... how bad would it be to use 750 Ohm instead of 680 and 499K Ohm instead of 470k?
Title: Re: $20 LCR ESR Transistor checker project
Post by: kelchm on January 08, 2018, 06:55:43 am
I just finished putting together an AY-AT kit with a color lcd. It seems to work if I hold down the encoder momentary switch, but turns off immediately when letting go of the switch.

Any ideas where to start with troubleshooting?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 08, 2018, 01:22:49 pm
Re-asking my question, hoping someone (Markus? :)) knows the answer... how bad would it be to use 750 Ohm instead of 680 and 499K Ohm instead of 470k?

Basically you can use different values as long as you update the constants for the probe resistors in the source. But with different values you also change the max. test current:
for 680 Ohms: I = 5 V / (680 Ohms + 40 Ohms) = 6.95 mA
for 750 Ohms: I = 5 V / (750 Ohms + 40 Ohms) = 6.33 mA
(the 40 Ohms are the internal resistance of the pin drivers)

This is about 10% less. The lower test current will have an impact on several measurements, like inductance for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 08, 2018, 01:33:52 pm
I just finished putting together an AY-AT kit with a color lcd. It seems to work if I hold down the encoder momentary switch, but turns off immediately when letting go of the switch.

Any ideas where to start with troubleshooting?

Please check the transistor which is controlled by the MCU to keep the power supply running.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on January 08, 2018, 05:51:31 pm
Basically you can use different values as long as you update the constants for the probe resistors in the source. But with different values you also change the max. test current:
for 680 Ohms: I = 5 V / (680 Ohms + 40 Ohms) = 6.95 mA
for 750 Ohms: I = 5 V / (750 Ohms + 40 Ohms) = 6.33 mA
(the 40 Ohms are the internal resistance of the pin drivers)

This is about 10% less. The lower test current will have an impact on several measurements, like inductance for example.
Awesome answer, thanks so much!

Will need to decide what to do, if trying to match 3 1% resistors to within 0.1%, change the settings or bet the right resistors... but at least I know for sure now
Title: Re: $20 LCR ESR Transistor checker project
Post by: kelchm on January 09, 2018, 12:23:18 am
Please check the transistor which is controlled by the MCU to keep the power supply running.

Excuse my ignorance, but which transistor is that and how do I check if it is functioning correctly?

I see the TL431A, but that looks to be a voltage regulator. I've attached a photo of my board.



Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on January 09, 2018, 01:59:20 am
I would have to check a schematic to answer which transistor, BUT my bet is on the fact that you left out the LED.
The LED is needed to supply the collector of the transistor held on by PD7.
I think if you install it, your problem should be solved.

Graham


Excuse my ignorance, but which transistor is that and how do I check if it is functioning correctly?

I see the TL431A, but that looks to be a voltage regulator. I've attached a photo of my board.

Title: Re: $20 LCR ESR Transistor checker project
Post by: kelchm on January 09, 2018, 02:21:54 am
I would have to check a schematic to answer which transistor, BUT my bet is on the fact that you left out the LED.
The LED is needed to supply the collector of the transistor held on by PD7.
I think if you install it, your problem should be solved.

Graham


Excuse my ignorance, but which transistor is that and how do I check if it is functioning correctly?

I see the TL431A, but that looks to be a voltage regulator. I've attached a photo of my board.

That was indeed the issue. I somehow cooked my first led but was able to dig up another red led from my parts drawer.  Working great now.
Title: Re: $20 LCR ESR Transistor checker project
Post by: crimsonknight3 on January 10, 2018, 09:46:35 pm
I have spent a few hours looking through this thread but haven't found anything (well someone asked a similar question but it was overlooked)

I got my t4 variant today (using the mega 328p + 8mhz) and immediately came back here and got a brain ache to figure out exactly which firmware to use, before using my Arduino UNO as isp to flash the device. cmd prompt shows that the device erases, flashes, then read okay, however, there seems to be zero change to the firmware. No menu (I have not rotary encoder to hand so just wanted to test the firmware while waiting for one) I checked the makefile and edited out the rotary encoder part, changed the font slightly and slowly checked every single parameter to make sure it was all in line with everything I know about the T4 and specifically the variant I have.

The only (slight?) clue I have is that avrdude reports that there is an invalid signature, and so I had to force it. However, I am 100% sure without a shadow of a doubt that the connections between the Arduino + the device are 100% correct. I originally tried using 3.3v on the Arduino however after looking closely at a post WAY back in this thread, I found that person to be using their UNO's 5v, so I tried that also and still "installs" fine but makes no difference to the device.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on January 11, 2018, 09:44:03 am
Did you flash both the Programflash (.hex) and EEprom file (.eep)
and did you flash the correct fuse settings?
Title: Re: $20 LCR ESR Transistor checker project
Post by: crimsonknight3 on January 11, 2018, 12:07:17 pm
Did you flash both the Programflash (.hex) and EEprom file (.eep)
and did you flash the correct fuse settings?

I forgot the fuse settings >.< What are they for the t3/4 (the yellow board)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on January 11, 2018, 08:21:56 pm
The fuses:
lfuse: 0xf7   hfuse: 0xd9   efuse: 0x04
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2018, 03:42:30 pm
I'm working on the IR decoder/sender tools and added a few more protocols to the sender and some optional ones to the decoder. The optional protocols are less common and can be activated by a compile time option:
  - IR60 (SDA2008/MC14497)
  - Matsushita (Panasonic MN6014, C5D6 / 11 bits)
  - NEC µPD1986C
  - RECS80 (standard & extended)
  - Sanyo (LC7461)
  - Thomson

Any suggestions for additional protocols?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on January 12, 2018, 05:56:45 pm
how are you doing on memory?

the K firmware pretty much cant go any further on common hardware because the flash is full!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2018, 07:01:49 pm
The firmware size depends on the features enabled and the display (& font). With all basic features, a ST7565 and the IR decoder plus optional protocols it's about 27kB. If you want to have all features you would need an ATmega644.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kelchm on January 12, 2018, 09:10:35 pm
Basically you can use different values as long as you update the constants for the probe resistors in the source.
What are the names of those constants? I took a quick look but did not see them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: The Soulman on January 12, 2018, 10:53:24 pm
I'm working on the IR decoder/sender tools and added a few more protocols to the sender and some optional ones to the decoder. The optional protocols are less common and can be activated by a compile time option:
  - IR60 (SDA2008/MC14497)
  - Matsushita (Panasonic MN6014, C5D6 / 11 bits)
  - NEC µPD1986C
  - RECS80 (standard & extended)
  - Sanyo (LC7461)
  - Thomson

Any suggestions for additional protocols?


Is it possible to a add the protocol for the fs9922 DMM chip?
This is a widely used chip and comes in a 4000 count "DMM3" and 6000 count "DMM4" variant, both use the same serial protocol.
Would be nice to be able to use it as a second display for my dmm's. (feeding it from a wireless link)  :-DMM
Attached Linked is the datasheet describing the protocol (from page 30).

If you implement this, don't bother with the bar graph it's useless at 3 updates per second.

http://www.ic-fortune.com/upload/Download/FS9922-DMM4-DS-13_EN.pdf (http://www.ic-fortune.com/upload/Download/FS9922-DMM4-DS-13_EN.pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Lenny on January 13, 2018, 12:13:14 pm
Select "show values" in the main menu to display the adjustment values and check if Vcc has changed. There's no dedicated indication that the external reference is used. Have you enabled HW_REF25 in config.h?


I have just come to it now.
The menu shows a value of 1085mV as Vcc. Can that be correct?

 I have not checked it before installing the LM4040.  ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 13, 2018, 12:30:02 pm
Basically you can use different values as long as you update the constants for the probe resistors in the source.
What are the names of those constants? I took a quick look but did not see them.

k-firmware: R_L_VAL & R_H_VAL (autoconf.h)
m-firmware: R_LOW & R_HIGH (config.h)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 13, 2018, 12:51:13 pm
Is it possible to a add the protocol for the fs9922 DMM chip?
This is a widely used chip and comes in a 4000 count "DMM3" and 6000 count "DMM4" variant, both use the same serial protocol.
Would be nice to be able to use it as a second display for my dmm's. (feeding it from a wireless link)  :-DMM
Attached Linked is the datasheet describing the protocol (from page 30).

If you implement this, don't bother with the bar graph it's useless at 3 updates per second.

http://www.ic-fortune.com/upload/Download/FS9922-DMM4-DS-13_EN.pdf (http://www.ic-fortune.com/upload/Download/FS9922-DMM4-DS-13_EN.pdf)

It's a RS232 TX flashed by an IR LED. An IR receiver module will have difficulties to pick that up, because it expects a modulated signal with a carrier frequency in a specific range. So we would need a custom receiver module for flashed IR.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 13, 2018, 12:53:04 pm
I have just come to it now.
The menu shows a value of 1085mV as Vcc. Can that be correct?

 I have not checked it before installing the LM4040.  ::)

1085mV would be Vref (the internal bandgap reference).
Title: Re: $20 LCR ESR Transistor checker project
Post by: The Soulman on January 13, 2018, 11:37:43 pm
Is it possible to a add the protocol for the fs9922 DMM chip?
This is a widely used chip and comes in a 4000 count "DMM3" and 6000 count "DMM4" variant, both use the same serial protocol.
Would be nice to be able to use it as a second display for my dmm's. (feeding it from a wireless link)  :-DMM
Attached Linked is the datasheet describing the protocol (from page 30).

If you implement this, don't bother with the bar graph it's useless at 3 updates per second.

http://www.ic-fortune.com/upload/Download/FS9922-DMM4-DS-13_EN.pdf (http://www.ic-fortune.com/upload/Download/FS9922-DMM4-DS-13_EN.pdf)

It's a RS232 TX flashed by an IR LED. An IR receiver module will have difficulties to pick that up, because it expects a modulated signal with a carrier frequency in a specific range. So we would need a custom receiver module for flashed IR.

Not all meters with this chip have ir output, some have Bluetooth or wifi others none at all, The hardware interface should be implemented by the hobbyist's suited to his personal needs.
I was thinking to use the frequency counter pin as the input?
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on January 14, 2018, 11:33:52 am
Is it possible to a add the protocol for the fs9922 DMM chip?
This is a widely used chip and comes in a 4000 count "DMM3" and 6000 count "DMM4" variant, both use the same serial protocol.
Would be nice to be able to use it as a second display for my dmm's. (feeding it from a wireless link)  :-DMM
Attached Linked is the datasheet describing the protocol (from page 30).

If you implement this, don't bother with the bar graph it's useless at 3 updates per second.

http://www.ic-fortune.com/upload/Download/FS9922-DMM4-DS-13_EN.pdf (http://www.ic-fortune.com/upload/Download/FS9922-DMM4-DS-13_EN.pdf)

It's a RS232 TX flashed by an IR LED. An IR receiver module will have difficulties to pick that up, because it expects a modulated signal with a carrier frequency in a specific range. So we would need a custom receiver module for flashed IR.

Not all meters with this chip have ir output, some have Bluetooth or wifi others none at all, The hardware interface should be implemented by the hobbyist's suited to his personal needs.
I was thinking to use the frequency counter pin as the input?
For me next step is adapt Bluetooth and wifi options to detect and send remote signals like harmony hubs. Deviate maybe to a true universal remote branch :) but all for 50 euros max. Logitech sells a good solution over 160.anyway IR is dead long live BT

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: Fumio on January 17, 2018, 03:41:45 am
hello: I know this is much, much later than your post but in the event it may help someone else, I offer this information. I had same problem as you push rotary switch and flicker than nothing. My solution: transistor t103  an S9014 located just below the red led on the board was not conducting to ground. Replaced and all was well. To check this it is possible to run ground from negative side of red led to ground. If it is t103 it should work.
Regards Fumio
Title: Re: $20 LCR ESR Transistor checker project
Post by: Argiros on January 17, 2018, 11:26:28 pm
I bought recently the GM328B,  with the smd circuit it is new with a color screen . The board named Geek Teches and has in the back of the screen an sd card slot!. Strange but I think it is not used at all for the moment. I believe that the quality is very good, but I didn't check the measurements so far but the menu is missing many things and the font colors are AWFUL small and difficult to see red in Blue background! Thats why I tried to program it.Also I think that the rotary models are far better! and easier to use.

I thought it was better than GM328 but not! I tried to program it with a pickit2 but I brick it. And now pickit cant see it at all and the device showing a white screen when power is on.
Can anyone know how I can reset it ? I tried pushing the 1st btn and powering it on waitting nothing. Also the 2nd button and both nothing. The 328P chip is a small smd soldered in the circuit and it is difficult to access it straight.

Also what firmware is compatible for this device ?
How we can delete all the eprom and data from this chip ?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 18, 2018, 11:11:16 am
The GM328B's display seems to to be a ST7735. The precompiled version of the k-firmware for the GM328 (mega328_GM328) won't work obviously. So you would have to reverse engineer the pinout and configure the firmware accordingly. You can use the k or m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Argiros on January 18, 2018, 03:10:31 pm
Thank you madires !  Yes thats an ST7735. Sorry mate but I dont understand "So you would have to reverse engineer the pinout and configure the firmware accordingly"
If you can explain it a bit more...

I can restore it to "factory" settings because I saved: 1 the original flash , 2 the eeprom and 3 the fuse settings , IF I can delete it or "put" the chip in programming mode.

BUT HOW ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on January 18, 2018, 04:48:26 pm
Thank you madires !  Yes thats an ST7735. Sorry mate but I dont understand "So you would have to reverse engineer the pinout and configure the firmware accordingly"
If you can explain it a bit more...

I can restore it to "factory" settings because I saved: 1 the original flash , 2 the eeprom and 3 the fuse settings , IF I can delete it or "put" the chip in programming mode.

BUT HOW ?
If you put wrong fuses maybe you need to rewrite chip with parallel programmer.

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: Technobabble_ on January 18, 2018, 08:47:08 pm
Hey all. Did anybody ever compile a list comparing the different versions of kits (barebones vs completed, smd vs through-hole models, etc.)? I understand each vendor may have its own part-of-the-week in theirs.

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Argiros on January 19, 2018, 12:51:27 am
Thanx perieanuo !
I can hook up directly to ATMEGA 328 OR to the board ISP interface from an LPT port ? And I can use the avrdude or avrdudes then  ? Or I can use the USBASP USBISP AVR Programmer better ?

Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on January 19, 2018, 12:53:36 am
Or just spend a couple of bucks for a new AVR chip...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Argiros on January 19, 2018, 01:08:32 am
I will make it work even if I desolder the smd ATMEGA 328 with my hot air gun, put it on a breadboard and reprogram it with arduino or whatever. I want this sh.t to work although I ordered a new rotary one 328A.
But I dont know how to make his flash and eeprom and what fuses I must use for the 328b. I dont know what constants I must change before compiling the source. Maybe someone make a precompile hex for the 328b models. (-;
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fumio on January 19, 2018, 04:18:48 am
T3 s9014 is likely bad. Mine was bad and gave same symptom as you state. To check: before you start to unsolder the existing transistor run a ground from negative side of RED LED to ground. Doing this will create the ground that T3 should provide
Hope this is helpful
Fumio
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on January 19, 2018, 07:18:19 am
I will make it work even if I desolder the smd ATMEGA 328 with my hot air gun, put it on a breadboard and reprogram it with arduino or whatever. I want this sh.t to work although I ordered a new rotary one 328A.
But I dont know how to make his flash and eeprom and what fuses I must use for the 328b. I dont know what constants I must change before compiling the source. Maybe someone make a precompile hex for the 328b models. (-;
Search I posted myself compiled 1.28 hex/eep for ay-at longtime ago.

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: Gregi on January 19, 2018, 10:42:04 am
Hi guys, this is my first post here. Maybe a dumb question and maybe not. I want to buy one of those testers. Can you please give me some advice of which one is the best you can get today. What I mean is which one can be modded upgraded or whatever. I am kinda lost in these 170+ pages. I have seen that some of you ppl already made some modifications but I am lost anyway  :wtf:

So which one is the newest and what to look out for?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 19, 2018, 11:26:39 am
The AY-AT is the most interesting clone at the moment. If you want a tester with all hardware options you would have to build one yourself based on the ATmega644/1284 circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gregi on January 19, 2018, 01:41:49 pm
Great... Ty for quick answer. Btw anyone made atmega644/1284 based tester and if so does the firmware exist or I should start from scratch?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 19, 2018, 03:10:35 pm
Karl-Heinz's excellent documentation includes a circuit for the ATmega644/1284 and I've posted a PDF of my 644/1284 dev kit a while ago. Both firmwares (k & m) support the ATmega644/1284.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on January 19, 2018, 06:07:20 pm
Karl-Heinz's excellent documentation includes a circuit for the ATmega644/1284 and I've posted a PDF of my 644/1284 dev kit a while ago. Both firmwares (k & m) support the ATmega644/1284.

Has anybody made any PCBs or a layout for a 644/1284 version available ?  I have a bunch of 1284 chips.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 19, 2018, 06:20:01 pm
Please see https://drive.google.com/drive/folders/0B4yqyYy2DaakZzBVU3JDSXB6S1E ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on January 19, 2018, 06:31:44 pm
Please see https://drive.google.com/drive/folders/0B4yqyYy2DaakZzBVU3JDSXB6S1E ;)

I did a little poking around there and did not see any layouts for a '1284 based board.  What I'd like to find is a PCB for the '1284 chip in a DIP package.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gregi on January 19, 2018, 09:55:41 pm
What else you want to see on the DIP board? Lets call it like that. I have some experience with pcb making so i will look into it.

Edit: but hell its a nice looking board full SMD. Maybe it would be a blasphemy to modify it lol ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on January 19, 2018, 10:47:47 pm
What else you want to see on the DIP board?

Support for all the new fangled features would be nice.  Needs a nice color LCD.   I prefer the DIP package because it's so easy to fry the processor with a wayward charged cap, etc. and changing a socketed DIP is a lot easier than SMD reworking a SMD package.   Plus, I have a pile of Mega128's in the DIP40 package.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gregi on January 20, 2018, 12:17:19 am
It's like this... pcb is wide as DIP40, actualy a bit wider. It would look bad :P but it is doable (draw the board from scratch)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Argiros on January 21, 2018, 07:54:54 pm

Re: $20 LCR ESR Transistor checker project
« Reply #4383 on: January 19, 2018, 03:18:48 PM »
Say ThanksReplyQuote
T3 s9014 is likely bad. Mine was bad and gave same symptom as you state. To check: before you start to unsolder the existing transistor run a ground from negative side of RED LED to ground. Doing this will create the ground that T3 should provide
Hope this is helpful
Fumio


Thanx Fumio,
I see my board GM328B has q1 q2 q3  smd tranzistors Their values are: a19t  , tl431a  , 1am
When I power on the led is lighting..
Maybe the q3 is bad...

For the conversation about the new models and features, I have to say that a bigger screen will be much nicer and also the new features and better accuracy are always welcomed !
Title: Re: $20 LCR ESR Transistor checker project
Post by: kelchm on January 21, 2018, 09:37:03 pm
Is there any way to program a raw ATMEGA328P without an USPASP or equivalent programmer? I have several Arduinos available as well as a FTD1232 board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2018, 11:08:51 am
No, even a bootloader has to be programmed first. BTW, Karl-Heinz modified Optiboot to program the EEPROM also, in case someone is interested in ATmega bootloaders.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on January 22, 2018, 11:55:07 am
Yes you can use Arduino to write the Arduino bootloader or the ay-at fw on the new chips. Search Arduino as isp

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Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on January 22, 2018, 07:00:05 pm
Is there any way to program a raw ATMEGA328P without an USPASP or equivalent programmer? I have several Arduinos available as well as a FTD1232 board.

maybe this way
https://www.youtube.com/watch?v=muP1dp73Mdg (https://www.youtube.com/watch?v=muP1dp73Mdg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: kelchm on January 25, 2018, 02:24:27 am
Yes you can use Arduino to write the Arduino bootloader or the ay-at fw on the new chips. Search Arduino as isp
I ended up being lazy and just got a USBasp.  ;D

Has anyone else had issues with running a 20MHz crystal? I experienced really bad display corruption (missing/inforrect characters, random dots) and general flakiness after swapping the crystal and uploading the new firmware. I then swapped in a 16MHz crystal which seems to work fine.

I'm using 1.26M.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MDM3D on January 25, 2018, 02:37:32 am


Yes you can use Arduino to write the Arduino bootloader or the ay-at fw on the new chips. Search Arduino as isp
I ended up being lazy and just got a USBasp.  ;D

Has anyone else had issues with running a 20MHz crystal? I experienced really bad display corruption (missing/inforrect characters, random dots) and general flakiness after swapping the crystal and uploading the new firmware. I then swapped in a 16MHz crystal which seems to work fine.

I'm using 1.26M.

Yes I thought it might have been from the long leads I soldered on for flashing but haven't had time to downgrade back to 16Mhz.

Sent from my SAMSUNG-SM-G900A using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: kelchm on January 25, 2018, 03:06:14 am


Yes you can use Arduino to write the Arduino bootloader or the ay-at fw on the new chips. Search Arduino as isp
I ended up being lazy and just got a USBasp.  ;D

Has anyone else had issues with running a 20MHz crystal? I experienced really bad display corruption (missing/inforrect characters, random dots) and general flakiness after swapping the crystal and uploading the new firmware. I then swapped in a 16MHz crystal which seems to work fine.

I'm using 1.26M.

Yes I thought it might have been from the long leads I soldered on for flashing but haven't had time to downgrade back to 16Mhz.

Sent from my SAMSUNG-SM-G900A using Tapatalk
I tried a couple different MCUs, no change. I think it's an issue with the LCD.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on January 25, 2018, 07:22:10 am
Yes you can use Arduino to write the Arduino bootloader or the ay-at fw on the new chips. Search Arduino as isp
I ended up being lazy and just got a USBasp.  ;D

Has anyone else had issues with running a 20MHz crystal? I experienced really bad display corruption (missing/inforrect characters, random dots) and general flakiness after swapping the crystal and uploading the new firmware. I then swapped in a 16MHz crystal which seems to work fine.

I'm using 1.26M.
Nope. It's the crystal or maybe incorrect capacitors for him if you compiled correctly. I use 20M for longtime

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Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 25, 2018, 11:36:58 am
Has anyone else had issues with running a 20MHz crystal? I experienced really bad display corruption (missing/inforrect characters, random dots) and general flakiness after swapping the crystal and uploading the new firmware. I then swapped in a 16MHz crystal which seems to work fine.

I'm using 1.26M.

Some compatibles of LCD controllers don't support the maximum clock rate of the genuine controller. In this case you can slow down the SPI write function by adding a few wdt_reset().
Title: Re: $20 LCR ESR Transistor checker project
Post by: kelchm on January 25, 2018, 02:06:14 pm
Some compatibles of LCD controllers don't support the maximum clock rate of the genuine controller. In this case you can slow down the SPI write function by adding a few wdt_reset().
Yeah, this is probably the issue. Slowing down the SPI write would defeat the purpose of running the 20MHz crystal though (faster display updates).

I wish there was a way to have a better idea of just what you were buying on eBay/Aliexpress/etc.

Title: Re: $20 LCR ESR Transistor checker project
Post by: jewelie on January 26, 2018, 04:43:48 pm
Hi folks  :)

I think this is probably the best place to put this post, apologies if not as I'm not a seasoned poster here?

After reading these posts I recently got the through-hole GM328 version of the transistor tester (red board, through hole components so I can easily hack later, with the 160x128 display and 7735 driver, and also with terminals for voltage measurement and frequency generator signal output.)  By default it's running the 1.12k firmware, so I've not bothered hacking it yet.  On this occasion I cheated and bought it ready assembled so that if it didn't work they couldn't blame me and my soldering.  ;)

One caveat I've had playing with it is that the external voltage measurement option seems low: 8.84V reads as 8.6V, 2.5V reads as 2.42V (so Vext is ~3% off.)

I know that's still really quite a small tolerance for measurement but it seems odd to be that off given that-

So, any ideas why the Vext voltage measurements would be low by ~3% when everything else is so accurate?


Julie
x



Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 26, 2018, 05:46:28 pm
Intriguing! Could you please also check higher voltages >= 12V?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hussamaldean on January 26, 2018, 06:47:30 pm
Hi,
I got the LCR T5 one and the tester is so slow that the resistance mmeasurement takes like 12 second for 1K value,  the capacitance is 10 time less than the label value, and I can't self-test it. when it reaches 14%, the device shuts down
any solution ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jewelie on January 26, 2018, 07:51:30 pm
Intriguing! Could you please also check higher voltages >= 12V?

Will do, when I've charged up my batteries.

However, there's something else odd about it anyway - although it says 1.12k it has IR Encoder etc so it must be a slightly hacked default firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 26, 2018, 08:44:44 pm
I got the LCR T5 one and the tester is so slow that the resistance mmeasurement takes like 12 second for 1K value,  the capacitance is 10 time less than the label value, and I can't self-test it. when it reaches 14%, the device shuts down
any solution ?

My guess is that the ATmega is running at 1MHz. Please check the fuse settings (external quartz crystal and 1:1 clock divider).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 26, 2018, 08:50:51 pm
However, there's something else odd about it anyway - although it says 1.12k it has IR Encoder etc so it must be a slightly hacked default firmware.

Do you mean IR receiver/decoder or rotary encoder?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jewelie on January 26, 2018, 09:38:57 pm
However, there's something else odd about it anyway - although it says 1.12k it has IR Encoder etc so it must be a slightly hacked default firmware.

Do you mean IR receiver/decoder or rotary encoder?

Good point.  It has a hardware rotary encoder.  The firmware has options for connecting IR Decoder, IR Receiver, DHT11 Temp & Humidity sensor, etc.  I thought the proper 1.12k firmware didn't have that.  It sounds like all the Banggood ones ship with the same firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hussamaldean on January 27, 2018, 02:50:23 am
I got the LCR T5 one and the tester is so slow that the resistance mmeasurement takes like 12 second for 1K value,  the capacitance is 10 time less than the label value, and I can't self-test it. when it reaches 14%, the device shuts down
any solution ?

My guess is that the ATmega is running at 1MHz. Please check the fuse settings (external quartz crystal and 1:1 clock divider).
the crystal is 8MHz and how can I check the fuses ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on January 27, 2018, 03:18:49 am
I like AVR Dudess (http://blog.zakkemble.co.uk/avrdudess-a-gui-for-avrdude/ (http://blog.zakkemble.co.uk/avrdudess-a-gui-for-avrdude/)), use either an arduino as ISP or a USBASP or similar to read the fuses on the chip. (Either solder wires to the pins on the board or put it on a breadboard if you have the supplies.  :)

Then AVR fuse calc  (http://www.engbedded.com/fusecalc/ (http://www.engbedded.com/fusecalc/)) to see what they are set to.

Sorry nix the breadboard as it looks like LCR t5 is surface mount, but it does look like it has connections for the ICSP header. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hussamaldean on January 27, 2018, 03:45:43 am
I like AVR Dudess (http://blog.zakkemble.co.uk/avrdudess-a-gui-for-avrdude/ (http://blog.zakkemble.co.uk/avrdudess-a-gui-for-avrdude/)), use either an arduino as ISP or a USBASP or similar to read the fuses on the chip. (Either solder wires to the pins on the board or put it on a breadboard if you have the supplies.  :)

Then AVR fuse calc  (http://www.engbedded.com/fusecalc/ (http://www.engbedded.com/fusecalc/)) to see what they are set to.

Sorry nix the breadboard as it looks like LCR t5 is surface mount, but it does look like it has connections for the ICSP header. :)
when I launch it, it says libusb0 is missing !!!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on January 27, 2018, 04:14:00 am
Sorry, been a while. I believe zadig will install the proper libusb files

http://zadig.akeo.ie/ (http://zadig.akeo.ie/)

scroll to libusb-win32

install wcid driver

Title: Re: $20 LCR ESR Transistor checker project
Post by: hussamaldean on January 27, 2018, 04:04:09 pm
Sorry, been a while. I believe zadig will install the proper libusb files

http://zadig.akeo.ie/ (http://zadig.akeo.ie/)

scroll to libusb-win32

install wcid driver
I managed to upload the software but I ended up with burnt UNO :(
and the tester doesn't work anymore
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on January 27, 2018, 10:51:06 pm
Hello everyone,

It's been a while since I haven't logged in to this thread. I own a transistor tester that I bought on BangGood a while ago and it has version 1.12K on it.

Is that the latest version, or is there a more recent version? I am wanting to test small capacitors 5-10pf and I wonder if there is a newer version of the firmware. If so, could you point me in the right direction for the hex and eep files?

A photo is attached of my tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on January 28, 2018, 12:17:27 am

I managed to upload the software but I ended up with burnt UNO :(
and the tester doesn't work anymore

Like literally burnt? Hook up the wires wrong?  Anything happen when power applied to either?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hussamaldean on January 28, 2018, 05:26:47 am

I managed to upload the software but I ended up with burnt UNO :(
and the tester doesn't work anymore

Like literally burnt? Hook up the wires wrong?  Anything happen when power applied to either?
nop, it was the bootloader not responding and I managed to fix it
I knew now what wrong with the old one :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: jewelie on January 29, 2018, 01:07:41 am
Intriguing! Could you please also check higher voltages >= 12V?

Done.

8.84V reads as 8.6V, 2.5V reads as 2.42V and 28.4V reads as 27.8V.

As I say, it seems odd given the accuracy of the Vcc voltage it measures, the 10:1 resister divider for the Vext input and the internal Vref.  Resistance measurements seem about the same amount off too.

I've another ATMega328p coming on to which I'll put the real 1.13k firmware and see what we get.  With luck I'll be able to binary-chop my way into working out where the loss of accuracy is coming from.

Regards,
Julie
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 29, 2018, 11:20:09 am
I suspected the internal bandgap reference (1.1V). But since the higher voltages are off by the same percentage it's something else. The firmware simply measures the voltage and multiplies it by the factor of the voltage divider which can be changed by editing the resistor values in the source code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on January 31, 2018, 12:21:38 pm
Hello everyone,

It's been a while since I haven't logged in to this thread. I own a transistor tester that I bought on BangGood a while ago and it has version 1.12K on it.

Is that the latest version, or is there a more recent version? I am wanting to test small capacitors 5-10pf and I wonder if there is a newer version of the firmware. If so, could you point me in the right direction for the hex and eep files?

A photo is attached of my tester.

Anyone?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 31, 2018, 02:45:21 pm
Usually you'll find the links to the firmware repo somewhere in the last ten pages ;) Running the k-firmware you could put a cap with maybe 47pF in parallel or use the SamplingADC. The m-firmware starts measuring at 5pF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on January 31, 2018, 05:59:21 pm
Hello Madires,

Thank you for your reply. In fact, it's been a while that I wanted to try the M-firmware. Can you point me in the right direction so that I get the good version for my tester which is a 2 line tester?

I made an ISP port for it so, is it possible to get just the hex and eep files without having to compile it?

Many thanks again for your help!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 31, 2018, 06:39:33 pm
Sorry, I don't provide compiled firmware because there are too many different hardware versions. The links for the latest firmware versions:
- k-firmware: https://github.com/svn2github/transistortester/tree/master/Software/trunk
- m-firmware: https://github.com/svn2github/transistortester/tree/master/Software/Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 31, 2018, 06:43:06 pm
Computers have this awesome ability called "search".
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on January 31, 2018, 07:22:06 pm
Sorry, I don't provide compiled firmware because there are too many different hardware versions. The links for the latest firmware versions:
- k-firmware: https://github.com/svn2github/transistortester/tree/master/Software/trunk
- m-firmware: https://github.com/svn2github/transistortester/tree/master/Software/Markus

Ok, Madires, I understand. Is there a guide somewhere for which version matches which type of screen? My machine is like one of the first ones, sold in kit on BangGood with the 2 line display. Would that be the default version?

Tks again!
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on January 31, 2018, 07:45:07 pm
Easiest way to identify is look for a similar image to yours then the display listed or look at the driver chip, I think yours is the 1602 LCD which is 2 line 16 character, so I would think 2x16_menu may work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: kelchm on February 01, 2018, 06:05:32 am
Computers have this awesome ability called "search".
Have you ever actually tried searching on this forum? You're better off using Google along with the title of the thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 01, 2018, 07:16:38 am
@kelchm
The forum search (ie the one in the screenshot i posted) worked just fine for finding the firmware link.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hussamaldean on February 01, 2018, 09:15:19 am
Hi,
I have one of these in the picture and it is T5
but it doesn't work and the screen is blank
any hope to solve it ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 01, 2018, 10:36:38 am
Get the schematic, grab a DMM and start checking ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hussamaldean on February 01, 2018, 10:47:41 am
Get the schematic, grab a DMM and start checking ;)
let me explain
when I press the button, the screen lit and off
it was working and was so slow and when calibrate it, kaboom everything gone
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 01, 2018, 01:31:59 pm
Possibly wrong fuse settings (CKDIV8 set/programmed).
Title: Re: $20 LCR ESR Transistor checker project
Post by: hussamaldean on February 01, 2018, 01:50:39 pm
Possibly wrong fuse settings (CKDIV8 set/programmed).

I tried but I can't change the fuse registry either
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 01, 2018, 02:04:08 pm
Is the ATmega write protected (lock bits set)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hussamaldean on February 01, 2018, 02:11:25 pm
Is the ATmega write protected (lock bits set)?
LB is 0x3F
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 01, 2018, 02:25:23 pm
If there's nothing wrong with your programming it seems to be a bad ATmega.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gregi on February 01, 2018, 05:18:48 pm
I have just finished my tester today and it worked for about 2 seconds. It was powered with 10v supply from my psu and said low batt voltage 6.8X volts and then shuts off. Ofc it wont turn on anymore even on 9V battery. Red LED is not on, display is black. any ideas what to check?

i bought this one
Link to aliexpress (https://www.aliexpress.com/item/2017-Russian-M328-Transistor-Tester-DIY-LCR-Diode-Capacitance-ESR-voltage-meter-PWM-Square-wave-Frequency/32800783868.html?spm=2114.search0104.3.3.7cd2efb1oFqCwQ&ws_ab_test=searchweb0_0,searchweb201602_5_10065_10068_10344_10342_10343_10340_10341_10084_10083_10618_10307_10301_10303_10313_10059_10534_100031_10103_441_442_10624_10623_10622_10621_10620_10142,searchweb201603_32,ppcSwitch_7&algo_expid=0d8dfc69-5c87-4ded-9d61-5f6fcaf481f3-0&algo_pvid=0d8dfc69-5c87-4ded-9d61-5f6fcaf481f3&transAbTest=ae803_5&priceBeautifyAB=0")
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 01, 2018, 05:36:14 pm
That's an AY-AT (schematic in this thread) and typical problems are a reversed SVR05-4 or a bad transistor in the power circuitry.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gregi on February 02, 2018, 08:44:53 am
Can I use 78L05 instead of HT7550? HT7550 is not available in TO92 package except from china.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 02, 2018, 10:48:12 am
Yes, but a MCP1702-5002 would be better.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gregi on February 02, 2018, 02:41:57 pm
I have tested the voltages in the circuit and i had 0.2 volts on the out pin of ht7550 so i removed it and tried with 78L05 (thats what i had in my workshop) and it works. So 7550 worked for 2 seconds and died :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on February 03, 2018, 12:03:52 am
Glad you got it working.
Pinout is very different between HT7550 and 78L05. Could you have put the 7550 in wrong? I have done it more than once with these newer regulators.

As Markus mentioned, MCP1702-5002 would be much better (results more accurate). BTW, it has the same pinout as the HT7550

Graham


I have tested the voltages in the circuit and i had 0.2 volts on the out pin of ht7550 so i removed it and tried with 78L05 (thats what i had in my workshop) and it works. So 7550 worked for 2 seconds and died :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: dave356 on February 03, 2018, 06:59:30 am
Hi Guy's

I just purchased 2 of the AY-AT testers (1 kit, 1 assembled) and am going to install some better components.

  680ohm  0.1%
470kohm  0.1%
LM4040 2.5v ref
MCP1702 5v reg

I have also ordered 4 extra ATMEGA328 chips so I can try different FW versions
without overwriting original. (And to have spares)

Can I also install a 16mhz crystal with stock firmware or will I have to reflash.
Will stock firmware work with a 16mhz crystal???

Anything else to replace to improve accuracy?


Thanks


Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on February 03, 2018, 01:55:36 pm
Hi Guy's

I just purchased 2 of the AY-AT testers (1 kit, 1 assembled) and am going to install some better components.

  680ohm  0.1%
470kohm  0.1%
LM4040 2.5v ref
MCP1702 5v reg

I have also ordered 4 extra ATMEGA328 chips so I can try different FW versions
without overwriting original. (And to have spares)

Can I also install a 16mhz crystal with stock firmware or will I have to reflash.
Will stock firmware work with a 16mhz crystal???

Anything else to replace to improve accuracy?


Thanks
1.yes, have to reflash.
2.yes,it will work, but incorrectly

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Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 03, 2018, 03:05:25 pm
Can I also install a 16mhz crystal with stock firmware or will I have to reflash.
Will stock firmware work with a 16mhz crystal???

You need to change the MCU clock in the source code to 16MHz (Makefile) and compile a new firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pappkopp on February 03, 2018, 03:57:43 pm
Is pd6 supposed to have power the whole time? My wont stay on unless i hold the button down..
Title: Re: $20 LCR ESR Transistor checker project
Post by: kelchm on February 03, 2018, 04:44:35 pm
Code: [Select]
AVR Memory Usage
----------------
Device: atmega328

Program:   36136 bytes (110.3% Full)
(.text + .data + .bootloader)

Data:        257 bytes (12.5% Full)
(.data + .bss + .noinit)

EEPROM:      882 bytes (86.1% Full)
(.eeprom)

Using 1.31m and the IR options sure do eat up a lot of space on the lowly ATMega328p... I'd really love to build one of the ATMega1284 variants, but I really don't want to spend close to $100 getting the boards made. Has anyone set up a group buy for these in the past?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 03, 2018, 05:51:39 pm
Is pd6 supposed to have power the whole time? My wont stay on unless i hold the button down..

Using the 328 standard pin assignment PD6 switches the power, i.e. the pin is set high by the MCU at start-up.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on February 03, 2018, 07:07:24 pm
Hi Guy's

I just purchased 2 of the AY-AT testers (1 kit, 1 assembled) and am going to install some better components.

  680ohm  0.1%
470kohm  0.1%
LM4040 2.5v ref
MCP1702 5v reg

Out of curiosity, where did you find the 680 Ohm and 470 Ohm 0.1% resistors? I can't find the exact values in 0.1% (digikey, mouser). 1% are easy to find in every value, but 0.1% are much harder
Title: Re: $20 LCR ESR Transistor checker project
Post by: phil from seattle on February 03, 2018, 07:34:37 pm
Hi Guy's

I just purchased 2 of the AY-AT testers (1 kit, 1 assembled) and am going to install some better components.

  680ohm  0.1%
470kohm  0.1%
LM4040 2.5v ref
MCP1702 5v reg

Out of curiosity, where did you find the 680 Ohm and 470 Ohm 0.1% resistors? I can't find the exact values in 0.1% (digikey, mouser). 1% are easy to find in every value, but 0.1% are much harder

Hmmm, just did a search on mouser found 470, 470K and 680 .1% in both smd and th. The TH ones are pricey though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 03, 2018, 09:28:57 pm
Sorry, I don't provide compiled firmware because there are too many different hardware versions. The links for the latest firmware versions:
- k-firmware: https://github.com/svn2github/transistortester/tree/master/Software/trunk
- m-firmware: https://github.com/svn2github/transistortester/tree/master/Software/Markus

Hello Madires,

I bought 2 new testers by by Electronics Studio photo attached. It is based on the ST7565 controller. I was able to compile and install the k version (1.13) by using the makefile in the mega328_MK-328 directory of trunk and all worked well.

I want to install the 1.31M version on one of the testers but I have been unable to compile a version that works. I used the ST7565R configuration of the config_328.h file, everything compiles OK but the version doesn't work. Does the M version support this controller?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 03, 2018, 09:47:47 pm
If the parameters in the config.h are as below then the microcontroller will use voltage regulator (  MCP1702-5002) or reference voltage (TL431)?




#define UREF_VCC         5001


//#define HW_REF25


#define UREF_25           2495



#define UREF_OFFSET      0
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 03, 2018, 10:13:06 pm
I bought 2 new testers by by Electronics Studio photo attached. It is based on the ST7565 controller. I was able to compile and install the k version (1.13) by using the makefile in the mega328_MK-328 directory of trunk and all worked well.

I want to install the 1.31M version on one of the testers but I have been unable to compile a version that works. I used the ST7565R configuration of the config_328.h file, everything compiles OK but the version doesn't work. Does the M version support this controller?

The m-firmware supports the ST7565. Presumably you need to adjust the pin assignment for the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 03, 2018, 10:17:46 pm
If the parameters in the config.h are as below then the microcontroller will use voltage regulator (  MCP1702-5002) or reference voltage (TL431)?

#define UREF_VCC         5001
//#define HW_REF25
#define UREF_25           2495

#define UREF_OFFSET      0

This configuration disables the optional 2.5V external voltage reference and sets Vcc to 5001mV.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 03, 2018, 11:19:03 pm
I bought 2 new testers by by Electronics Studio photo attached. It is based on the ST7565 controller. I was able to compile and install the k version (1.13) by using the makefile in the mega328_MK-328 directory of trunk and all worked well.

I want to install the 1.31M version on one of the testers but I have been unable to compile a version that works. I used the ST7565R configuration of the config_328.h file, everything compiles OK but the version doesn't work. Does the M version support this controller?

The m-firmware supports the ST7565. Presumably you need to adjust the pin assignment for the display.

Thank you Madires for your response. How does the pin assignment compare to the K version...can I deduce the pin assignment from the K version source files?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 04, 2018, 09:26:40 am
Before checking the display let's look for basic stuff. Does the tester turn on and stays turned on for a while (LED lit)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 04, 2018, 10:04:48 am
It does turn on, but I see nothing on the screen. It stays on for approx. 45 seconds before turning off, or if I hit the Test button again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 04, 2018, 02:59:23 pm
So the power control seems to work. I've checked the k-firmware's config.h for the ST7565's pin assignment and it uses the same defaults like the m-firmware. Could you please try another default value for the contrast (the MK-328's Makefile sets 55 as default)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on February 04, 2018, 05:16:58 pm
Hi Guy's

I just purchased 2 of the AY-AT testers (1 kit, 1 assembled) and am going to install some better components.

  680ohm  0.1%
470kohm  0.1%
LM4040 2.5v ref
MCP1702 5v reg

Out of curiosity, where did you find the 680 Ohm and 470 Ohm 0.1% resistors? I can't find the exact values in 0.1% (digikey, mouser). 1% are easy to find in every value, but 0.1% are much harder

Hmmm, just did a search on mouser found 470, 470K and 680 .1% in both smd and th. The TH ones are pricey though.
Do you have a link? The ones I found can only be bought in huge reels, not just one... and I'm asking about TH, not SMD, since I plan to solder them on the opposite side and use them as hook points to program the Atmega in-circuit
Title: Re: $20 LCR ESR Transistor checker project
Post by: GBowes on February 04, 2018, 05:32:39 pm
Not sure if this link will work.
https://www.mouser.com/Passive-Components/Resistors/_/N-5g9nZ1yzvvqx?P=1z0z819Z1z0vpm5Z1z0x74aZ1yzekil (https://www.mouser.com/Passive-Components/Resistors/_/N-5g9nZ1yzvvqx?P=1z0z819Z1z0vpm5Z1z0x74aZ1yzekil)

If not, go to Mouser.com and enter the mouser part numbers in the search bar.

Mouser part numbers
279-H4680RBYA
71-RN55C-B-470K/R

Graham
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 04, 2018, 06:36:26 pm
So the power control seems to work. I've checked the k-firmware's config.h for the ST7565's pin assignment and it uses the same defaults like the m-firmware. Could you please try another default value for the contrast (the MK-328's Makefile sets 55 as default)?

Ok, set the contrast at 55 but still don't see anything on the screen?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 04, 2018, 08:58:29 pm
It must be something else but I don't got any idea at the moment. Are you sure that you've enabled the ST7565 configuration?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 04, 2018, 09:07:27 pm
It must be something else but I don't got any idea at the moment. Are you sure that you've enabled the ST7565 configuration?
Presume you mean this one, or maybe I have the wrong one as I don't have a rotary encoder on my tester?

*
 *  ST7565R, SPI interface (bit-bang)
 *  - settings for Electronic Assembly EA DOGM/DOGL128-6
 *  - uses LCD_CS to support rotary encoder in parallel at PD2/3
 */
#define LCD_ST7565R
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD4            /* port pin used for /RES */
#define LCD_A0           PD3            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD1            /* port pin used for SI (LCD's data input) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     55             /* default contrast (0-63) */
#define FONT_8X8_VF                     /* 8x8 font, vertically aligned & flipped */
#define SYMBOLS_24X24_VFP               /* 24x24 symbols, vertically aligned & flipped */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SI         /* port pin used for MOSI */
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 04, 2018, 09:40:38 pm
The ATmega328's default pin assignment for the ST7565 is:

Code: [Select]
#define LCD_RESET        PD0            /* port pin used for /RES (optional) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 04, 2018, 10:26:09 pm
The ATmega328's default pin assignment for the ST7565 is:

Code: [Select]
#define LCD_RESET        PD0            /* port pin used for /RES (optional) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */

That worked Madires! Cool! I had to bring down the contrast back to 11 however otherwise I was getting a black box.  Will give it a test drive and report back.

Thank you for all your help, you're amazing!
Title: Re: $20 LCR ESR Transistor checker project
Post by: dave356 on February 05, 2018, 06:58:23 am
Is this all the stuff I need to start programming the chip???
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 05, 2018, 09:31:56 am
looks about right
Title: Re: $20 LCR ESR Transistor checker project
Post by: oldswamm on February 05, 2018, 12:29:46 pm
I only discovered these little wonders a couple months ago.  I now own 2, an LCR-T6, all SMT, and an ay-at, through hole, and have ordered parts for upgrades to the second.
I want to sincerely thank Markus and Karl-Heinz, and all the others who helped develop and refine this.  Wish I'd had it 50yrs ago, or 40, or....

I would like to discuss an improved version, using a shield for an Arduino mega2560.  If this is already being done, or even seriously discussed, please point me to it.  And if I seem presumptuous jumping in here like this, I apologize.  It's the way I am, (I'd like to order prototype boards right after the holidays).  If this isn't already being done, and you don't hate all my ideas, it obviously should be opened in a new topic.

I'm thinking about numerous 'improvements' over the 328.  Some of my ideas may be based on misconceptions, I'll admit.  I'll try and list them (ideas, not misconceptions). 

If any user doesn't want a feature, just don't populate it.

More than 2 resistor values?  If the board were designed for 4 different resistor values, different users could populate 2, 3, or 4.  If we used 1k8, 3k6, 900k, and 1m8 at 18v, we would be able to put 5mA, 10mA, 15mA, 5uA, 10uA, and 15mA into 0 ohms.  Probably would be better to choose wider spacing such as 15mA, 3mA, 100uA, and 5uA?

Higher voltage.  I'm leaning toward 18v, mostly because that's the recommended max for the CD4066B.  If there's a better part choice, I haven't found one I like (cheap too).  I would put all 3 of one value resistor to one IC, connected to one rail, which should give the best resistance match.  2 ICs in parallel would halve the resistance, and with careful selection would reduce the mismatch.  The 4066 has a 10mA max, so would probably want to parallel the ones to the low value resistor, and the ones to 18v and ground, at least.  I expect the ones shown in red on my sketch are superfluous.
(http://)
I would put pads for resistors in parallel with the lower value .1% resistors, and in series with the high value .1% resistors (have to cut a trace), so we can 'trim' them.  If you can get access to a 5-1/2 digit meter, you can measure the .1% resistors, then calculate the trim values needed (I have friends with access, I hope).  Same trick for the voltage dividers for the op amps and reference voltage.  Measure the regulator voltages while you have access to that nice meter.  It would be neat if we could push it to 4-1/2 digit accuracy.

I would make provision for a 14bit 200sps ADCs (MAX11101EUB+, OK?), or an optional cheaper 12bit.  All 3 sample and holds would be triggered simultaneously, and 3 separate serial data streams would then download simultaneously. 

I didn't find a 3p relay that I liked for shorting the inputs, so ordered some A5W-K dpdt, and will use 2 of them, which is what I would probably use for this shield.  Fairly small, and cheap.

I would include a frequency counter pre-scaler, and possibly an optional HF pre-pre-scaler (I haven't investigated, but I'll bet we can buy a 'module' for very little).  BNC(s). 

A separate zener tester.

How about a crystal oven?  2 resistors epoxied to the sides of the crystal, down against the pcb, and a thermistor epoxied to the can.  It would use 1 or 2 processor outputs connected to the resistors, and the thermistor to an adc channel.  We don't need to raise it's temperature very much, so needn't use much energy.  A little packing foam above and below would help insulate it. 

Obviously the tester would have to remain on for some time when ovens are used.  I would probably use a 5Ahr Li-Po cell, and include a USB charger jack to recharge a cell phone or tablet, thereby gaining almost unlimited on time as a bonus, so wouldn't care.  Hey, this thing would probably be in my carry-on anyway, right?

A 2 or 3 range, auto ranging volt meter.  I don't remember how to do auto ranging, and would have to research. Banana jacks.

A protected input to connect to a current shunt, 50uV?

A simple buffered waveform generator.  Once the hardware is in place, people will write increasingly complex waveforms....

The whole power supply should be on the shield, including 5v for the processor. 

Any suggestions for a voltage regulator that beats .1% significantly?  Would temperature controlled oven help there?  I even considered using another 4066 and/or transistors to switch in load resistors in an effort maintain a more constant load (as if testing loads were constant....).  Actually, if it would help, we could switch in resistors with the unused switches in the 4066s, (0 to 50mA in 2.5mA steps?).  Would have to be based on a calculation, but combined with a load resistor at the regulator, we could keep the load to within a few %.  Just thinking out load here.  The regulator seams to me to be the weak point, and I'm not sure how to improve it to the degree needed, at least not affordably.

I haven't counted, and might be pushing the pin count on the mega2560, but can always use a little logic to control the 4066s, which would save 10 or more pins.

Large color displays.  My eyes are at that age, or beyond.  :-)

I should mention that I don't want to be the one to make the software changes.  Old, cranky, and has hated programing for 40yrs+.  If we could agree on a design, I would have (bare) boards made, and would send some to someone willing to modify the software, at my own expense.

Thanks for listening,
Bob

P.S. If someone wants to help with this PM me.
I'll design the hardware, if someone wants to work on the software.
In spite of what Madires says, I think it would be reasonable to try and improve this device.  Now, not someday.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2018, 01:54:29 pm
There's already an Arduino shield made by pighixxx (http://forum.arduino.cc/index.php?topic=164112.0 (http://forum.arduino.cc/index.php?topic=164112.0)). He also ported the m-firmware to a sketch but the files aren't online at the moment (http://www.pighixxx.com (http://www.pighixxx.com)). You aren't the first one suggesting a tester with higher test voltages and more probe resistors. One of the main benefits of the current design is its simplicity. Adding the external switching and ADCs increases the complexity of hardware and firmware. This might be an idea for the future, possibly with a totally different MCU, but not now. Our next step is to move to the ATmega644/1284 for more flash, RAM and IO pins. If you're interested in a frequency counter you'll find a simple hardware option with input buffer, prescaler and crystal oscillators in Karl-Heinz' documentation. It's supported by both firmwares (k & m). Or do you fancy a touch screen? No problem! 8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 05, 2018, 02:01:41 pm
Hi,Madires!
There is a question on setup of a m-firmware on ST7735.How to shift or reduce the image on this clone?
Here its settings in config_328.h
* ST7735, SPI interface (bit-bang, 4 wire)
//#if 0
#define LCD_ST7735
#define LCD_COLOR /* color graphic display */
#define LCD_SPI /* SPI interface */
#define LCD_PORT PORTD /* port data register */
#define LCD_DDR DDRD /* port data direction register */
#define LCD_RES PD3 /* port pin used for /RESX (optional) */
//#define LCD_CS PD5 /* port pin used for /CSX (optional) */
#define LCD_DC PD2 /* port pin used for D/CX */
#define LCD_SCL PD0 /* port pin used for SCL */
#define LCD_SDA PD1 /* port pin used for SDA */
#define LCD_DOTS_X 128 /* number of horizontal dots */
#define LCD_DOTS_Y 160 /* number of vertical dots */
#define LCD_FLIP_X /* enable horizontal flip */
//#define LCD_FLIP_Y /* enable vertical flip */
#define LCD_ROTATE /* switch X and Y (rotate by 90°) */
#define LCD_LATE_ON /* turn on LCD after clearing it */
#define FONT_8X16_CYRILLIC_HF /* 8x16 cyrillic font, horizontally aligned & flipped */
#define SYMBOLS_30X32_HF /* 30x32 symbols, horizontally aligned & flipped */
#define SPI_BITBANG /* bit-bang SPI */
#define SPI_PORT LCD_PORT /* SPI port data register */
#define SPI_DDR LCD_DDR /* SPI port data direction register */
#define SPI_SCK LCD_SCL /* port pin used for SCK */
#define SPI_MOSI LCD_SDA /* port pin used for MOSI */
//#endif

Whether the LCD_OFFSET_X and LCD_START_Y commands work?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 05, 2018, 02:58:58 pm
If you shift to the right, you won't be able to see the symbols on the right.

Looks as if the casing  opening is too narrow. Did you try it without the top cover to see if you have full image?
Title: Re: $20 LCR ESR Transistor checker project
Post by: oldswamm on February 05, 2018, 03:01:45 pm
Yes I've read Karl-Heinz' pdfs, and a lot of this forum topic.  I've studied all the schematics I could find.

I don't see the advantage of the ATmega644/1284 over the 2560.  If the ATmega2560 isn't enough, what processor would you suggest?

I couldn't get at the schematics for pighixxx's shield.  Was he using high voltage and hi res ADCs?  If not, I don't see the advantage.

I know I'm not the first to suggest SOME of these things.  Am I the first who wants to build it NOW?  How far in the future do you think it needs to be put off?  I don't have that many more years on this earth, so what gets postponed, pretty much is canceled as far as I'm concerned.

The firmware changes for high voltage and external ADCs shouldn't be that hard, or porting it to an arduino sketch, I just don't have the temperament for SW.  I tend to smash keyboards and other offensive parts of the computer when I do.  If none of the software folks think the improvements are worthwhile, I probably won't bother building it.

And no, it will no longer be a $20 tester.  It will cost 3 to 6 times that.  Your tester is designed to be inexpensive, and it's great for the price.  I just think the same theory of operation could be applied to a slightly more accurate, more versatile device, and am willing to accept that it will cost more.

If you really think it's a terrible idea that can't possibly be built for years to come, I'll delete my posts and go away....

If you think one of more of my ideas is wrong, please be specific.  I honestly don't see why it can't be built at this time, or for that mater on an Arduino mega2560.  I could wish it was a little faster , but it has 4 to 8 times the memory of the 328, and 3 or 4 times the ports.
Bob
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 05, 2018, 03:26:20 pm
If you shift to the right, you won't be able to see the symbols on the right.

Looks as if the casing  opening is too narrow. Did you try it without the top cover to see if you have full image?
It is correct, but I have a task how to place the image without having spoiled appearance of a tester. It is possible to cut wider hole, never late to make it  :) It is possible to reduce resolution instead of 128x160 to make 124x156
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2018, 03:54:39 pm
Whether the LCD_OFFSET_X and LCD_START_Y commands work?

They aren't supported by the ST7735 driver.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2018, 04:06:41 pm
It is correct, but I have a task how to place the image without having spoiled appearance of a tester. It is possible to cut wider hole, never late to make it  :) It is possible to reduce resolution instead of 128x160 to make 124x156

Should be possible but you would have less characters per line and lines.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2018, 04:23:58 pm
I don't see the advantage of the ATmega644/1284 over the 2560.  If the ATmega2560 isn't enough, what processor would you suggest?

I was talking about the advantage over the 328  ;) The ATmega2560 is a different beast. IIRC, the k-firmware supports it.

I couldn't get at the schematics for pighixxx's shield.  Was he using high voltage and hi res ADCs?  If not, I don't see the advantage.

No, it's compatible with the basic design.

The firmware changes for high voltage and external ADCs shouldn't be that hard, or porting it to an arduino sketch, I just don't have the temperament for SW.  I tend to smash keyboards and other offensive parts of the computer when I do.  If none of the software folks think the improvements are worthwhile, I probably won't bother building it.

The basic support of external ADCs and switching isn't the problem. Changing all measurements and checks to use the additional capabilities is the hard part.

If you really think it's a terrible idea that can't possibly be built for years to come, I'll delete my posts and go away....

It's not a bad idea. We simply don't have the resources to implement everything. So we focus on what can be achieved reasonably.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oldswamm on February 05, 2018, 04:33:25 pm
Sorry.  The hardware is quite easy.  I didn't realize using different voltages and resistor values, or increasing the resolution would require an unreasonable software upgrade.
I'm gone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 05, 2018, 06:30:11 pm
Well I have to admit that I really like the M version of the software. Madires, you have done an amazing job!! Thank you.

Do you want me to post the changes required for the tester in the photo so that if anyone else has the same model, they could compile the M version for it?

Many thanks again!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2018, 07:01:44 pm
You're welcome! And please post the changed settings. I'll add them to the Clones file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 05, 2018, 07:16:20 pm
Ok, if you own one of these testers, marked Electronics Studio on the back and would like to install the M firmware,  you have to make the following adjustments in the ST7565 section in the config_328.h file, copy attached:

/*
 *  ST7565R, SPI interface (bit-bang)
 *  - settings for Electronic Assembly EA DOGM/DOGL128-6
 *  - uses LCD_CS to support rotary encoder in parallel at PD2/3
 */


#define LCD_ST7565R
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD0            /* port pin used for /RES (optional) */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
#define FONT_8X8_VF                     /* 8x8 font, vertically aligned & flipped */
#define SYMBOLS_24X24_VFP               /* 24x24 symbols, vertically aligned & flipped */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SI         /* port pin used for MOSI */

I am also enclosing version 1.31M compiled versions of the .eep and .hex files in version1_31.zip file for your convenience.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 05, 2018, 08:43:52 pm
Hello Madires,

This might sound like a dumb question, but how would I reverse the power on of the tester so that it starts in Hold mode, and if I press rapidly twice it would start in continuous probing mode?

EDIT: Oops, I think I found it. I just need to switch OP_AUTOHOLD with OP_CONTINOUS in main.c? Is that right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: eemes on February 05, 2018, 08:52:32 pm
This might sound like a dumb question, but how would I reverse the power on of the tester so that it starts in Hold mode, and if I press rapidly twice it would start in continuous probing mode?
I was also thinking the same, but it might be a reason to do it as it is done. I would opt for a compile-time option.

BTW: what do you find better in M-firmware compare to K-firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2018, 09:16:55 pm
That's easy ;) In main() in main.c there's a section 'operation mode selection'. Change the following lines:

Code: [Select]
  UI.OP_Mode = OP_CONTINOUS;            /* set default mode: continous */
...
  if (Test > 1) UI.OP_Mode = OP_AUTOHOLD;

to

Code: [Select]
  UI.OP_Mode = OP_AUTOHOLD;            /* set default mode: auto hold */
...
  if (Test > 1) UI.OP_Mode = OP_CONTINOUS;

BTW, a long key press (>300ms) activates the alternative mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 05, 2018, 09:17:14 pm
This might sound like a dumb question, but how would I reverse the power on of the tester so that it starts in Hold mode, and if I press rapidly twice it would start in continuous probing mode?
I was also thinking the same, but it might be a reason to do it as it is done. I would opt for a compile-time option.

BTW: what do you find better in M-firmware compare to K-firmware?

For one thing, I was able to measure a 12pf capacitor with the M version, whereas the K version did not detect it. Also, I like the feel of the M version, it runs fast and smooth. I also like the K version, so I have 2 testers with one with M version and the other with K version. I find myself reaching out more on the M version when I need to use them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eemes on February 05, 2018, 10:01:16 pm
Going for a walk before bed, I was thinking about the possibility to have both FW, and choose at start-up which to use.
The problem could be memory (probably not on 328), and name clashes ....
I have to think a bit more and maybe give a try when I'll find some time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 06, 2018, 12:14:32 am
Hello Madires,

In ESR mode, is there any way I can set it to probe continuously instead of with a keypress?

Tks,
Title: Re: $20 LCR ESR Transistor checker project
Post by: dave356 on February 06, 2018, 01:39:26 am
Someone (who is intimately familiar with all the units) needs to start a new thread with listings/links to which firmware goes with which units.

Show picture of which unit along with the firmware/revisions and a description of features in each firmware
and if any board/hardware upgrades are needed to run the specific firmware.  Updated as necessary with new releases.

Would make it easier than trying to read 180 pages to find descriptions and upgrades for the unit you have.

Maybe make it a "sticky" so as to have easy access to it.

Allow no discussions, only info for updates, so as to steer the discussion over to this thread.

Would make it soo much easier on us noobs.

Thoughts???
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 06, 2018, 03:28:54 am
There's no need to read 180 pages. Most of what a noob needs is in the repository (which has firmware for each model), and documentation. And I think that there is already enough information there to overwhelm.

I think what is more needed, is a FAQ or boiled down quick-start guide. There have already been posts made with a summary of the basics needed to get started. They just need to be "stickied".
Title: Re: $20 LCR ESR Transistor checker project
Post by: dave356 on February 06, 2018, 04:02:31 am
That's a good example.

What and where is the REPOSITORY??

Most would not know what you are talking about unless they have read a good bit of the thread.

Then a lot would not know what to do with the info anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 06, 2018, 05:12:56 am
Most would not know what you are talking about unless they have read a good bit of the thread.
I know! The whole first five posts.  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: theleakydiode on February 06, 2018, 05:53:09 am
I personally think the information ITT is easier to read for layman's like me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 06, 2018, 12:11:57 pm
In ESR mode, is there any way I can set it to probe continuously instead of with a keypress?

Maybe a timeout for TestKey() will to the trick. In extras.c in function ESR_Tool() there's
Code: [Select]
Test = TestKey(0, CURSOR_BLINK);    /* wait for user feedback */

The zero means 'no timeout', i.e. TestKey() waits until the user presses the test button. You could change the zero to 3000 (for 3000ms) for example. Be aware that you have to wait for the cursor to the exit the tool by two short key presses.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 06, 2018, 12:16:07 pm
Going for a walk before bed, I was thinking about the possibility to have both FW, and choose at start-up which to use.
The problem could be memory (probably not on 328), and name clashes ....
I have to think a bit more and maybe give a try when I'll find some time.

Should be feasible with an ATmega1284.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 06, 2018, 12:24:10 pm
Someone (who is intimately familiar with all the units) needs to start a new thread with listings/links to which firmware goes with which units.

Show picture of which unit along with the firmware/revisions and a description of features in each firmware
and if any board/hardware upgrades are needed to run the specific firmware.  Updated as necessary with new releases.

jakeisprobably is working on a FAQ/beginner's guide/overview thread, but I don't have any idea about the progress. Maybe he likes to chime in?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Miwer on February 06, 2018, 08:28:10 pm
Hi Guy's

I just purchased 2 of the AY-AT testers (1 kit, 1 assembled) and am going to install some better components.

  680ohm  0.1%
470kohm  0.1%
LM4040 2.5v ref
MCP1702 5v reg

Out of curiosity, where did you find the 680 Ohm and 470 Ohm 0.1% resistors? I can't find the exact values in 0.1% (digikey, mouser). 1% are easy to find in every value, but 0.1% are much harder

@robca - your profile doesn't state what part of the world you're from, but if anyone in Europe need these parts, they can all be purchased from reichelt.de in Germany:

Item + Item-no/link + price (at the time of writing):

680 ohm  0.1%   - MPR 680 (https://www.reichelt.de/Metal-0-1-100-Ohm-910-Ohm/MPR-680/3/index.html?ACTION=3&GROUPID=3103&ARTICLE=13051&START=0&OFFSET=100&) - €0,31 (x3)
470 kohm  0.1% - MPR 470K (https://www.reichelt.de/Metal-0-1-100-k-Ohm-1-00-M-Ohm/MPR-470K/3/index.html?ACTION=3&GROUPID=3105&ARTICLE=12984&START=0&OFFSET=100&) - €0,37 (x3)
LM4040 2.5v ref - LM 4040 AIZ2,5 (https://www.reichelt.de/ICs-LM-2000-LM-25576/LM-4040-AIZ2-5/3/index.html?ACTION=3&GROUPID=5466&ARTICLE=109411&START=0&OFFSET=100&) - €1,58
MCP1702 5v reg - MCP 1702-5002 (https://www.reichelt.de/ICs-MCP-1-2-/MCP-1702-5002/3/index.html?ACTION=3&GROUPID=5471&ARTICLE=90115&START=0&OFFSET=100&) - €0,65
16 MHz xtal        - 16,0000-HC49U-S (https://www.reichelt.de/Crystals-Quartz/16-0000-HC49U-S/3/index.html?ACTION=3&GROUPID=3173&ARTICLE=32852&START=0&OFFSET=100&) - €0,23
Atmega 328P-PU - ATMEGA 328P-PU (https://www.reichelt.de/Atmel-ATMega-AVRs/ATMEGA-328P-PU/3/index.html?ACTION=3&GROUPID=2959&ARTICLE=119685&START=0&OFFSET=100&) - €2,63

Total price: €7,13 (+ shipping)

Best regards,
Miwer
Title: Re: $20 LCR ESR Transistor checker project
Post by: fudmuffin on February 07, 2018, 07:06:13 am
(forum newbie alert  :D)

Hey all. I've recently built one of the M12864 DIY kits and I've run into a problem with flashing the latest firmware.

The firmware I have been trying is from https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/) (which I believe is correct for the M12864 DIY kits)

When I turn the device on, I get nothing but seemingly random numbers scrolling quickly across the top of the screen, and the device is unresponsive. The display is very high-contrast but you should be able to make out the numbers in the attached pic to see what I'm talking about.

Has anyone seen these scrolling random numbers before? I figure if it is showing characters on the screen then it can't be too far off working.

The device worked with the firmware it came with (aliexpress), and also works with other older firmware that I have found e.g. from https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg753902/#msg753902 (https://www.eevblog.com/forum/testgear/)

The fuses I am setting are 0xf7 0xd9 0xfc, per guides in this thread. The programmer I have been using is MiniPro TL866A, and I've been using the pre-compiled firmware. I thought I should ask if anyone knows what the trouble is, before attempting next steps.

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 07, 2018, 09:49:42 am
When I turn the device on, I get nothing but seemingly random numbers scrolling quickly across the top of the screen, and the device is unresponsive.

That's new to me. Please post photos of your board without LCD.

M328 is inserted correctly?

Perhaps something to do with the rotary encoder. Try disconnecting it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 07, 2018, 10:05:25 am
 I have managed to program the AY-AT clone for the first time with the k software and everything work fine.
I tried to program the m software too but there are some issues.
It doesnt want a capacitor to calibrate ony want to short probes.
The SELFTEST and ADJUSTMENT in the menu works the same - they run the calibration.
Capacitor measurement doesn,t work as it should, sometimes doesn,t detect, sometimes shows only capacitance and very rarely ESR.

I'm changing only those setting which are described in the "clones" file for the AY-AT.
What am I doing wrong?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 07, 2018, 10:26:05 am
When I turn the device on, I get nothing but seemingly random numbers scrolling quickly across the top of the screen, and the device is unresponsive. The display is very high-contrast but you should be able to make out the numbers in the attached pic to see what I'm talking about.

Have you programmed the EEPROM too?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 07, 2018, 10:33:39 am
I tried to program the m software too but there are some issues.
It doesnt want a capacitor to calibrate ony want to short probes.
The SELFTEST and ADJUSTMENT in the menu works the same - they run the calibration.
Capacitor measurement doesn,t work as it should, sometimes doesn,t detect, sometimes shows only capacitance and very rarely ESR.

Please read the 'Self Adjustment' section in the README file. The self-test is different from the self-adjustment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: fudmuffin on February 07, 2018, 02:16:22 pm
When I turn the device on, I get nothing but seemingly random numbers scrolling quickly across the top of the screen, and the device is unresponsive.

That's new to me. Please post photos of your board without LCD.

M328 is inserted correctly?

Perhaps something to do with the rotary encoder. Try disconnecting it.

The M328 (ATMEGA328P-PU) is connected correctly. I have re-programmed 6-7 times now between the r523 firmware mentioned earlier (which works) and the latest one from the repository (which I have the trouble with).

I have now tried compiling the latest firmware myself both with and without the "DWITH_ROTARY_SWITCH" and get the same result as the precompiled from the repository (scrolling numbers along top of screen).

I tried the 1.12k_r523 firmware again to check: The rotary encoder works with the 1.12k_r523 firmware (you can see the r523 firmware running in the attached picture).

Photos are attached of front and back of board, as well as another one where the scrolling numbers (that I am getting with the latest firmware) are easier to see.


Have you programmed the EEPROM too?

If you mean the .eep file to 'data memory', then yes. I am also setting the fuses as per the attached picture (which I sourced from elsewhere in the thread).

I guess unless there are other suggestions then tomorrow I will try removing the rotary encoder completely, and programming using avrdude instead of the TL866A - but I'm not confident either will make a difference...

Also - how do I check which revision/version number is the latest in the repository?

Thanks for your ideas!

Title: Re: $20 LCR ESR Transistor checker project
Post by: doktori on February 07, 2018, 03:10:47 pm
Hi this recently threw me for a curve.  Using the TL866 you must load the .epp file as Intel HEX format to the data memory.  Loaded as a BIN format the display will only show a scrolling line at the top of the display for the M12864 board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eemes on February 07, 2018, 03:47:38 pm
I bought a kit for AX (based on AtMega328P with color display 160x128 rotating encoder):
https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32785578867.html (https://www.aliexpress.com/item/2016-DIY-KITS-ATMEAG328P-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Signal/32785578867.html)

I replaced these  parts (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025).
Actaully 16Mhz quarz instead 20MHz.

I managed to run both FWs (for 16MHz I have to recompile both with the right options). But I have some questions:
- what does 16MHz quartz bring? Faster execution? Is there any other (side) effect, like precision?
- since I replaced 2.5 voltage reference (and also 5V Vcc). I wonder if I have to compile the FWs with some other options.
 In particular M-firmware. Should I enable/uncomment: HW_REF25 (and also set UREF_25 to the proper value (which one)?

Are there some other options that I should enable/disable after replacing the above mentioned parts?

BTW: big thx to both developer of the tester, and really really good update (!) documentation!!!  :-+ :-+ :clap:

PS: I tried the idea that I mentioned  here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1418991/#msg1418991) (to build and run both FWs together) I've managed to get the flash, which is, unfortunately, ~64kB big so I could not try on my AtMega328P  :(.  It has sens as each FW has already ~32kB.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 07, 2018, 04:27:37 pm
With 16MHz the display output is faster, especially for color displays, and time related measurements (capacitance, inductance) are a little bit more precise while supporting lower limits. If you want to use an external voltage reference with the m-firmware please enable HW_REF25 and set UREF_25 to the typical value stated in the reference's datasheet (or measure the voltage with a 6.5 digit or better DMM). No other changes are required besides changing the MCU clock rate in the Makefile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Seekonk on February 07, 2018, 04:31:01 pm
I had an interesting transistor the other day that was shorted.  It indicated as two diodes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 07, 2018, 06:40:56 pm
I tried to program the m software too but there are some issues.
It doesnt want a capacitor to calibrate ony want to short probes.
The SELFTEST and ADJUSTMENT in the menu works the same - they run the calibration.
Capacitor measurement doesn,t work as it should, sometimes doesn,t detect, sometimes shows only capacitance and very rarely ESR.

Please read the 'Self Adjustment' section in the README file. The self-test is different from the self-adjustment.

I have read that and now I understant the difference but still the tester does not show esr for capacitors bigger than 470 micro.
Usuaally 470 is  (not always) ok but 1000 micro and higher not.
Sometimes shows  0,00 ohm but usualy shows only capacitance and leakage.

Ri -20,4ohm
Ri+22.8ohm
C0 41pF
R0 0,14ohm
vref 1060mV
Vcc 5001mV
Acomp -47mv
Title: Re: $20 LCR ESR Transistor checker project
Post by: eemes on February 07, 2018, 07:26:43 pm
With 16MHz the display output is faster, especially for color displays, and time related measurements (capacitance, inductance) are a little bit more precise while supporting lower limits. If you want to use an external voltage reference with the m-firmware please enable HW_REF25 and set UREF_25 to the typical value stated in the reference's datasheet (or measure the voltage with a 6.5 digit or better DMM). No other changes are required besides changing the MCU clock rate in the Makefile.
So 20MHz would be even better in terms of performance and precision?
Is it better (=more precise measurements) to use external voltage reference (or to stay with Vcc in case if both are quite accurate)?
For which component is the value of UREF_25 in the config.h
is 2500mv typical voltage for LM4040AIZ-2.5?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 07, 2018, 07:30:10 pm
When the tester doesn't display the ESR for electrolytic caps then the ESR measurement failed for some reason. For example one reason would be if the measured ESR (including R0) is lower than R0 (the resistance of the probe leads/pins), usually caused by contact problems.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 07, 2018, 07:35:53 pm
So 20MHz would be even better in terms of performance and precision?
Is it better (=more precise measurements) to use external voltage reference (or to stay with Vcc in case if both are quite accurate)?
For which component is the value of UREF_25 in the config.h
is 2500mv typical voltage for LM4040AIZ-2.5?

Not so much for precision but for display speed in case of a high resolution color display like ILI9341. An external voltage reference helps if its tolerance is about 10 times better than the tolerance of the voltage regulator. IIRC, the LM4040AIZ-2.5's typical voltage is 2.495V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 07, 2018, 07:56:05 pm
When the tester doesn't display the ESR for electrolytic caps then the ESR measurement failed for some reason. For example one reason would be if the measured ESR (including R0) is lower than R0 (the resistance of the probe leads/pins), usually caused by contact problems.

Maybe, but why it works on k firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 07, 2018, 08:16:45 pm
I don't know. I can't test my firmware with all the different versions and variants of the testers available. It's simply impossible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eemes on February 07, 2018, 08:28:51 pm
An external voltage reference helps if its tolerance is about 10 times better than the tolerance of the voltage regulator. IIRC, the MCP1702-5002E's typical voltage is 2.495V.
So in case of using MCP1702-5002E regulator for Vcc (tolerance 0.4%), and heaving M4040AIZ-2.5  (0.1%) as 2.5V external reference it is not big sense to use the external reference? Or it still has sense if the external reference is available?

Edited: replaced M4040AIZ-2.5 with MCP1702-5002E (copy-paste probelm)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 07, 2018, 08:46:23 pm
The MCP1702-5002 is a 5V LDO and not a 2.5V voltage reference. If you're using the MCP1702-5002 an additional 2.5V reference isn't recommended.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dave356 on February 07, 2018, 10:31:21 pm
Hi guys,
I have a T4 that will not run the self-test
I want to try to reprogram it,
Is the 6pin header area to the left of the chip able to be used for programming if I install a pin header?
Thought I noticed somewhere that it was used for programming after installing pins.

Also, what is a T4 with "strip-grid"
I noticed T4 with different traces on back called this.


Title: Re: $20 LCR ESR Transistor checker project
Post by: fudmuffin on February 08, 2018, 03:34:02 am
Hi this recently threw me for a curve.  Using the TL866 you must load the .epp file as Intel HEX format to the data memory.  Loaded as a BIN format the display will only show a scrolling line at the top of the display for the M12864 board.

Thank you very much. This was exactly what I was doing wrong with the TL866. Loading the .eep as INTEL HEX format did the trick, and the latest firmware is now working. I guess my mistake was not apparent when loading the older firmware as there was no vital .eep data in it. Thanks to all and I look forward to continue learning from this thread :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 08, 2018, 09:24:40 am
I don't know. I can't test my firmware with all the different versions and variants of the testers available. It's simply impossible.

I wrote that on K software my tester works but thats not true, after some time it displays message "uncalibrated"

I found this information in documentation of k software:
At this place I will give you an additional important hint. Never do a measurement with connected ISP plug!
The ISP interface influences the measurement.

Could it be that the programming cables cause the issues with your software too? By the cables I mean about 4cm long from microcontroller to 6 pin isp plug. The cables are lying on the pcb.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 08, 2018, 11:28:20 am
I have a T4 that will not run the self-test
I want to try to reprogram it,
Is the 6pin header area to the left of the chip able to be used for programming if I install a pin header?
Thought I noticed somewhere that it was used for programming after installing pins.

Also, what is a T4 with "strip-grid"
I noticed T4 with different traces on back called this.

Yep, it's the ISP. I have no idea about a 'T4 strip-grid' but Karl-Heinz uses the term 'strip grid' for a tester built on a veroboard. It has a different pin assignment to keep the wiring simple.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 08, 2018, 11:51:26 am
I wrote that on K software my tester works but thats not true, after some time it displays message "uncalibrated"

I found this information in documentation of k software:
At this place I will give you an additional important hint. Never do a measurement with connected ISP plug!
The ISP interface influences the measurement.

Could it be that the programming cables cause the issues with your software too? By the cables I mean about 4cm long from microcontroller to 6 pin isp plug. The cables are lying on the pcb.

The reason is that three pins of the MCU are shared between ISP and probe/test resistors. The length of the traces (and wires in your case) should be kept as short as possible, and the layout should keep the traces away from noisy stuff. I don't think a few centimeters are a problem. More likely the wires are picking up some signal from another trace/wire. A few mV can already screw up the ESR measurement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 08, 2018, 07:07:53 pm
I wrote that on K software my tester works but thats not true, after some time it displays message "uncalibrated"

I found this information in documentation of k software:
At this place I will give you an additional important hint. Never do a measurement with connected ISP plug!
The ISP interface influences the measurement.

Could it be that the programming cables cause the issues with your software too? By the cables I mean about 4cm long from microcontroller to 6 pin isp plug. The cables are lying on the pcb.

The reason is that three pins of the MCU are shared between ISP and probe/test resistors. The length of the traces (and wires in your case) should be kept as short as possible, and the layout should keep the traces away from noisy stuff. I don't think a few centimeters are a problem. More likely the wires are picking up some signal from another trace/wire. A few mV can already screw up the ESR measurement.

Exactly that was the problem. The wires were under the ZIF socket and cause all the problems. I unsoldered them and problem disappeared.
Thank you very much  for help madires.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eemes on February 08, 2018, 09:00:57 pm
I want to power my Component/LCR tester (see here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1420328/#msg1420328)) with a (permanent) 9V battery. So I wonder what's power  consumption (=current).
I could measure ~30mA when running, and less than 0.2mA at stand-by (waiting for the button to be pressed). So I believe that I do not need a switch to completely disconnect the battery when I would not need the tester. Anyway, the best test will be seeing how long the battery will last.

Has someone on you already measured the consumed current?
From the current consumption in  stand-by I would say that AtMega328P is in deep sleep.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 08, 2018, 09:46:53 pm
The current is about 20nA for the power-off state (standard power circuitry, MCU switched off). Sleep modes are used while the tester is running, e.g. for delays like waiting for user feedback.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on February 08, 2018, 10:10:11 pm
The "Fish..." boards had a design defect.  The battery test voltage divider was across the power input and not after the power switch transistor.  It would drain the battery after a few weeks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on February 13, 2018, 12:14:21 pm
Is this all the stuff I need to start programming the chip???

Could I ask you for the links to these, please?
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on February 13, 2018, 02:10:16 pm
I'm diving into the LCR fray here. I haven't read all 182 pages, but I have read the past 25 or so. It sounds like the AY-AT board with the rotary encoder is the one to get at the moment. Thanks especially to madires for all his work on this project! It is truly amazing!

I'm fairly new to electronics mods although I have built many projects over the years. I apologize if these questions are so basic.

I want to run the M-firmware, so it looks like I need to make the mods shown here: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025

My questions are these:

1. The AY-AT kits that I'm seeing don't have the IR sensor. It's not that I really NEED that, but it would be cool to have. Is there a way to add the IR to that board?

2. The kits that I'm seeing come with a monochrome LCD display. Is it possible to swap out for a color LCD/OLED or is that not recommended at this time? If color is okay to use, which display is best for this application? The ILI9341?

3. I can't tell what ATMega chips are coming with the kits that I'm finding. It looks like maybe a 328P The posted specs are rather limited. Do I need to worry about this? What is the most recommended chip at this time?

4. Likewise, I can't tell what crystal comes with the kits. Is it simply a matter of swapping out for a 20Mhz? The ATMega won't mind? I'm guessing not since the specs at http://www.microchip.com/wwwproducts/en/ATmega328p (http://www.microchip.com/wwwproducts/en/ATmega328p) indicate that it supports 20Mhz. Just want to make sure.

Thanks in advance for any assistance!

J

Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on February 13, 2018, 02:21:13 pm
Is this all the stuff I need to start programming the chip???

Could I ask you for the links to these, please?
Example for 10 pin to 6 pin adapter:
https://www.aliexpress.com/item/10-Pin-to-6-Pin-Adapter-Board-for-AVRISP-MKII-USBASP-STK500-High-Quality/32843191858.html (https://www.aliexpress.com/item/10-Pin-to-6-Pin-Adapter-Board-for-AVRISP-MKII-USBASP-STK500-High-Quality/32843191858.html)

Example for USBASP v2.0:
https://www.aliexpress.com/item/1pcs-Free-shipping-USB-ISP-USBasp-USBisp-Programmer-for-51-ATMEL-AVR-download-support-Win-7/32702960733.html (https://www.aliexpress.com/item/1pcs-Free-shipping-USB-ISP-USBasp-USBisp-Programmer-for-51-ATMEL-AVR-download-support-Win-7/32702960733.html)

Example AVR development board:
https://www.aliexpress.com/item/1pcs-ATMEGA8-ATMEGA48-ATMEGA88-Development-Board-AVR-NO-Chip-DIY-Kit/32342493690.html (https://www.aliexpress.com/item/1pcs-ATMEGA8-ATMEGA48-ATMEGA88-Development-Board-AVR-NO-Chip-DIY-Kit/32342493690.html)

or
https://www.aliexpress.com/item/AVR-ATMEGA16-Minimum-System-Board-ATmega32-USB-ISP-USBasp-Programmer/32728737348.html (https://www.aliexpress.com/item/AVR-ATMEGA16-Minimum-System-Board-ATmega32-USB-ISP-USBasp-Programmer/32728737348.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 13, 2018, 04:15:44 pm
I want to run the M-firmware, so it looks like I need to make the mods shown here: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025

You don't have to mod the AY-AT, but the mod will improve the tester for just a few bucks.

1. The AY-AT kits that I'm seeing don't have the IR sensor. It's not that I really NEED that, but it would be cool to have. Is there a way to add the IR to that board?

Simply start the IR decoder and connect the IR receiver module to the three probe pins.

2. The kits that I'm seeing come with a monochrome LCD display. Is it possible to swap out for a color LCD/OLED or is that not recommended at this time? If color is okay to use, which display is best for this application? The ILI9341?

If you prefer a large screen the ILI9341/9342, otherwise the ST7735 or ILI9163.

3. I can't tell what ATMega chips are coming with the kits that I'm finding. It looks like maybe a 328P The posted specs are rather limited. Do I need to worry about this? What is the most recommended chip at this time?

Yes, it's an ATmega328. There aren't any clones with ATmega644/1284 to buy yet, i.e. you would have to build one yourself. If you enable all features the 328 will be maxed out. And there are also some hardware options which require the additional I/O pins of a 644/1284.

4. Likewise, I can't tell what crystal comes with the kits. Is it simply a matter of swapping out for a 20Mhz? The ATMega won't mind? I'm guessing not since the specs at http://www.microchip.com/wwwproducts/en/ATmega328p (http://www.microchip.com/wwwproducts/en/ATmega328p) indicate that it supports 20Mhz. Just want to make sure.

It comes with an 8 MHz crystal, IIRC. I'd recommend the 16 MHz crystal because it will allow you to run both firmwares (k & m).
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on February 13, 2018, 05:36:16 pm
I want to run the M-firmware, so it looks like I need to make the mods shown here: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025

You don't have to mod the AY-AT, but the mod will improve the tester for just a few bucks.

1. The AY-AT kits that I'm seeing don't have the IR sensor. It's not that I really NEED that, but it would be cool to have. Is there a way to add the IR to that board?

Simply start the IR decoder and connect the IR receiver module to the three probe pins.

2. The kits that I'm seeing come with a monochrome LCD display. Is it possible to swap out for a color LCD/OLED or is that not recommended at this time? If color is okay to use, which display is best for this application? The ILI9341?

If you prefer a large screen the ILI9341/9342, otherwise the ST7735 or ILI9163.

3. I can't tell what ATMega chips are coming with the kits that I'm finding. It looks like maybe a 328P The posted specs are rather limited. Do I need to worry about this? What is the most recommended chip at this time?

Yes, it's an ATmega328. There aren't any clones with ATmega644/1284 to buy yet, i.e. you would have to build one yourself. If you enable all features the 328 will be maxed out. And there are also some hardware options which require the additional I/O pins of a 644/1284.

4. Likewise, I can't tell what crystal comes with the kits. Is it simply a matter of swapping out for a 20Mhz? The ATMega won't mind? I'm guessing not since the specs at http://www.microchip.com/wwwproducts/en/ATmega328p (http://www.microchip.com/wwwproducts/en/ATmega328p) indicate that it supports 20Mhz. Just want to make sure.

It comes with an 8 MHz crystal, IIRC. I'd recommend the 16 MHz crystal because it will allow you to run both firmwares (k & m).

Thank you for all the advice, madires!

It looks like the ILI9341/9342 will be too big to stay in keeping with the original design. Do you know if there are pinouts published for the AY-AT board? I want to make sure that the ST7735 or ILI9163 board that I purchase will be compatible.

I think the rest of your information has me all sorted! Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 13, 2018, 05:45:30 pm
jakeisprobably has posted a link to his AY-AT circuit diagram which includes also the mods.

Edit: Found the link: https://github.com/Upcycle-Electronics/AVR-Transistor-Tester
Title: Re: $20 LCR ESR Transistor checker project
Post by: perdrix on February 14, 2018, 11:12:06 am
Hi

Are there any ATMega644/1284 board designs yet?

Dave
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 14, 2018, 11:37:49 am
Yes ;) For example: https://drive.google.com/drive/folders/0B4yqyYy2DaakQjNmZ3NUTG1YcVU
Title: Re: $20 LCR ESR Transistor checker project
Post by: perdrix on February 14, 2018, 12:33:04 pm
Thanks

Could you point to any discussions about that version?

Dave
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 14, 2018, 02:36:52 pm
It's the circuit depicted in Karl-Heinz's documentation. I haven't seen any discussions about that circuit here but maybe you'll find more information in the Russian forum http://vrtp.ru/index.php?showtopic=16451 (http://vrtp.ru/index.php?showtopic=16451).
Title: Re: $20 LCR ESR Transistor checker project
Post by: sk760 on February 14, 2018, 10:24:53 pm
HI, i have an multifunction tester TC1 but is with Atmega324P not Atmega328
Can help someone with firmware for this tester?

Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on February 15, 2018, 08:01:20 am
I wrote that on K software my tester works but thats not true, after some time it displays message "uncalibrated"

I found this information in documentation of k software:
At this place I will give you an additional important hint. Never do a measurement with connected ISP plug!
The ISP interface influences the measurement.

Could it be that the programming cables cause the issues with your software too? By the cables I mean about 4cm long from microcontroller to 6 pin isp plug. The cables are lying on the pcb.

The reason is that three pins of the MCU are shared between ISP and probe/test resistors. The length of the traces (and wires in your case) should be kept as short as possible, and the layout should keep the traces away from noisy stuff. I don't think a few centimeters are a problem. More likely the wires are picking up some signal from another trace/wire. A few mV can already screw up the ESR measurement.
Hi Madires, can I just follow on with a question here, don't know if you saw my linked post below already.
Anyway I got that relay I was thinking of using to switch out the ISP leads, but would you say that would not work well anyway then?
Reason I have not tried it is because it was a bit bigger than what I understood from the specs so I would have to cut the case a bit...
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1387441/#msg1387441 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1387441/#msg1387441)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 15, 2018, 11:10:10 am
HI, i have an multifunction tester TC1 but is with Atmega324P not Atmega328
Can help someone with firmware for this tester?

The ATmega324 is supported by k and m-firmware but the TC-1 has an additional ATtiny for controlling some signals. Someone would have to reverse engineer that ATtiny. Another issue with the TC-1 is the poor pin assignment. By swapping two pins the circuit could support hardware SPI. :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 15, 2018, 11:23:26 am
Hi Madires, can I just follow on with a question here, don't know if you saw my linked post below already.
Anyway I got that relay I was thinking of using to switch out the ISP leads, but would you say that would not work well anyway then?
Reason I have not tried it is because it was a bit bigger than what I understood from the specs so I would have to cut the case a bit...
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1387441/#msg1387441 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1387441/#msg1387441)

If you keep the wires between the ISP and the relay short it might work fine. Give it a try. And I'd wait with the modification of the case, just in case ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: sk760 on February 15, 2018, 05:16:27 pm
Thank Madires for your response.
i reflash Atmega witk K and m firmware but LCD is White screen,you know if Attiny is problem for my case,or you cand give me an correct firmware...
Maybe can learn me how i can do this swapping.
HI, i have an multifunction tester TC1 but is with Atmega324P not Atmega328
Can help someone with firmware for this tester?

The ATmega324 is supported by k and m-firmware but the TC-1 has an additional ATtiny for controlling some signals. Someone would have to reverse engineer that ATtiny. Another issue with the TC-1 is the poor pin assignment. By swapping two pins the circuit could support hardware SPI. :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 15, 2018, 05:37:36 pm
The function of the ATtiny has to be figured out first before we are able to change the firmware configuration to cope with that. Maybe some firmware changes are required too. The two pins need to be swapped in the PCB layout (hardwired function in the MCU).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 16, 2018, 09:00:43 am
Hi, Madires!
I'm sorry!I apologize that incorrectly I gave information on the diagram LCR-TC-1.
One of owners of this instrument read marking of this chip of U4.
It is the STC15L104W controller. I put the corrected diagram to my message.
The main problem in testing of a firmware for this clone is that I have no it in hands! :D
Now about problems with M-Firmware.
1. The image was turned. I turned it in the necessary side. But at the edges of the display the noise strip is visible and also the picture is shifted on several pixels to the left and up. Fish8840TFT clone has the same problem and with the same Z180SN009 display. What you can advise for correction of this error? Reduction of resolution of the display to 124x156 does not correct a problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 16, 2018, 12:46:19 pm
IIRC, the Z180SN009 is based on the ST7735S. That controller supports up to 132x162 dots but the LCDs are 128x160 usually. A 128x160 LCD module could be wired starting at different addresses. Additionally the ST7735S has three pins for setting the LCD's resolution to either 132x162 or 128x160 which implies a specific wiring offset (moved to the mid). Maybe there are 128x160 modules wired starting at 1x1 but set to 132x162. When directions are flipped we'd get offset problems. So we need an option to shift x and y by the module specific offsets to cope with all the possible variations. And there's still the issue with the additional MCU controlling some important signals. Does anyone like to sponsor a TC-1 for reverse engineering and testing?
Title: Re: $20 LCR ESR: testing batteries?
Post by: pol098 on February 16, 2018, 11:28:55 pm
Has anybody thought of using this type of tester for testing the ESR of batteries? I haven't found any mention of this in the forum (maybe I missed it) or the documentation. This gives a very useful indication of state of charge of disposable batteries, and of condition (wear) of rechargeable batteries. I have a Bob Parker ESR meter intended for use with capacitors, but with circuitry that allows low-voltage batteries to be connected without harm. I use it to test the state of alkaline cells; it's also said to be useful for estimating the wear on LiIon batteries, which I can't yet confirm. The reports I've seen of damaging the $20 tester by connecting a charged capacitor make me leery of trying to test batteries with it (I don't yet have one).

ESR of alkaline batteries varies to some extent with manufacturer, as well as type; it's best to record the ESR of new batteries of the types you use. For example, for the alkaline AA batteries I use, the measuring technique of the Bob Parker meter reads around 0.12 ohm for a new one; depending upon the application 0.3 ohm upwards is time to change. This is very much not an exact science, but useful conclusions can be drawn. Possibly batteries could be safely tested with a low-ESR blocking capacitor in series?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2018, 10:58:55 am
The tester's standard circuit can't measure the ESR of a battery. However, it's possible to design a hardware option to do that (load method?).
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 17, 2018, 08:33:38 pm
Where can I set cpu frequency in m software? I can not find it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2018, 09:19:09 pm
In the Makefile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RGK on February 17, 2018, 09:36:11 pm
Do I understand correctly that if I build an "AY-AT" kit with all the supplied cheapo parts and substitute the high-grade parts jakeisprobably listed in post #3893, minus the 20MHz crystal, that the unit should power on run properly without updating the firmware?

BK
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2018, 09:47:33 pm
Yep, as long as you keep the 8MHz crystal. If you change the crystal the tester will still power on but the timing for several functions and measurements will be wrong.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RGK on February 17, 2018, 09:54:25 pm
Excellent - thanks for the quick reply/confirmation.

BK
Title: Re: $20 LCR ESR Transistor checker project
Post by: RGK on February 18, 2018, 01:48:41 am
Mouser is backordered on the MCP1702-5002E/TO part.  Any suitable alternates?

BK
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jacon on February 18, 2018, 11:39:37 am
Mouser is backordered on the MCP1702-5002E/TO part.  Any suitable alternates?

https://www.tme.eu/en/details/mcp1702-5002et/ldo-unregulated-voltage-regulators/microchip-technology/mcp1702-5002eto/ (https://www.tme.eu/en/details/mcp1702-5002et/ldo-unregulated-voltage-regulators/microchip-technology/mcp1702-5002eto/)

196 pcs as of now   :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: RGK on February 18, 2018, 08:03:44 pm
Mouser is backordered on the MCP1702-5002E/TO part.  Any suitable alternates?

https://www.tme.eu/en/details/mcp1702-5002et/ldo-unregulated-voltage-regulators/microchip-technology/mcp1702-5002eto/ (https://www.tme.eu/en/details/mcp1702-5002et/ldo-unregulated-voltage-regulators/microchip-technology/mcp1702-5002eto/)

196 pcs as of now   :)

Hoping to stick with Mouser and definitely USA.  Digikey has the part, but also need some parts that they don't carry, so trying to avoid multiple vendors.  Mouser does have the similar MCP1700 (max 6V) and an STMicroelectronics part.  Safest bet is to get the single MCP1702 from Digikey @ $0.51.

BK
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 18, 2018, 11:38:19 pm
You can also check Arrow. Sometimes they have stuff cheaper than Mouser and DigiKey, or free shipping. Their site can be cumbersome to find parts, but it can be worthwhile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 19, 2018, 06:18:11 pm
A quick update on the ST7735 offset issue. The new m-firmware version will have an X and Y offset setting for the ST7735.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RGK on February 23, 2018, 03:02:56 am
Do I understand correctly that if I build an "AY-AT" kit with all the supplied cheapo parts and substitute the high-grade parts jakeisprobably listed in post #3893, minus the 20MHz crystal, that the unit should power on run properly without updating the firmware?

BK

Assembled with all the high-grade parts and seems to be working well!  Still need to equip myself with the necessary tools before updating to m-firmware with crystal swap.  Thx for the good info.  Now to measure hfe of 400 parts...

BK
Title: Re: $20 LCR ESR Transistor checker project
Post by: technogeeky on February 23, 2018, 10:21:32 pm
Apparently Vellman is selling a "K8115" (https://www.jameco.com/z/K8115-Velleman-Component-Tester-Kit_2245343.html) component tester kit. For $65.

 :-DD

I guess it's about what you expect from full retail markup, but still.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 23, 2018, 10:58:52 pm
Gee, not even a case. :o
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 24, 2018, 12:10:19 pm
No LED, 78L05, LM385Z2.5, probe/test resistors possibly 1% tolerance, and a CD4050 as level shifter for the display. A very basic tester for 65 bucks. :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: imidis on February 24, 2018, 01:25:04 pm
I understand a mark up but that's more like robbery.  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 24, 2018, 08:22:08 pm
Yep, but not everyone puts forth the effort to avoid being robbed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 25, 2018, 06:05:38 pm
And some good news ;) We proudly present 1.32m:
- Additional output of components found to TTL serial interface.
- Driver for TTL serial interface (hardware and bit-bang).
- Updated var_russian.h (thanks to indman@EEVblog).
- Added support for X&Y offsets to ST7735 driver.
- Changed configuration of battery monitoring. Added switches to disable battery monitoring and to support an unmonitored external power supply.
- Added configuration switch to reverse operation mode selection at startup (UI_AUTOHOLD).
- Improved filter for Germanium BJTs with high leakage current in detection function for depletion mode FETs.
- Added fancy pinout to PCD8544 driver. Also fixed error in the PCD8544 driver's function LCD_CharPos() for rotated output.
- Improved functions for fancy pinout of 3-pin semiconductors and moved some functions to display.c. Output of pinout on separate screen if required.
- Added indicator for usage of external voltage reference (Show Values).
- Improved IR decoder and added optional protocols.
- Added more protocols to IR RC transmitter.

And thanks to indman for the vintage Germanium BJTs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 26, 2018, 08:05:22 am
Does anyone have the same problem with AY-AT? On Karl-Heinz Kübbeler software everything is ok but on Madires software there is a problem with capacitance measurement. The results are always about 4% less than it should be( I have checked that with a multimeter). Sometimes after programming the microcontroller (and callibration) it will happen that the result is very close - but it happens only once and never again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 26, 2018, 09:12:16 am
mebel,Markus firmware and madires firmware is the same! :D
You, probably meant Karl-Heinz Kübbeler  firmware?

Madires, big respect for your hard work!
I will a little add the list of changes in comparison with version 1.31 -
you added the beautiful vertical 8x16vfp font (gratitude to his author of NIckNI@VRTP.RU and Gennady_13@VRTP.RU for adaptation to the project).
Here is how version 1.32 with a new font on WEI_M8 clone looks
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 26, 2018, 09:28:38 am
mebel,Markus firmware and madires firmware is the same! :D
You, probably meant Karl-Heinz Kübbeler  firmware?


Yes, thanks.  I corrected.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 26, 2018, 10:27:11 am
Does anyone have the same problem with AY-AT? On Karl-Heinz Kübbeler software everything is ok but on Madires software there is a problem with capacitance measurement. The results are always about 4% less than it should be( I have checked that with a multimeter). Sometimes after programming the microcontroller (and callibration) it will happen that the result is very close - but it happens only once and never again.

Have you measured a film cap about 220nF to 2.2µF a few times before running the self adjustment? It's explained in the README.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 26, 2018, 10:48:49 am
Yes, I did that. I printed and read whole instruction.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 26, 2018, 01:15:52 pm
Do all caps read low or just a specific capacitance range?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 26, 2018, 01:54:46 pm
It seemed that the smaller ones ( for example film cap 100 nano) were quite ok

This evening I will check that more precisely. I will check the same capacitors with Kubbeler firmware, your firmware and then with multimeter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 26, 2018, 05:45:30 pm
Do all caps read low or just a specific capacitance range?

Here are the test results on the latest firmwares.

Capacitor          Aneng AN8009        Kubbeler             Markus
1µF                         950nF               982nF(.13)            979nF(.78)
2,2nF                     2,241nF             2,230nF               2275nF
10nF                       9933pF             9914pF                10,04nF(100.3)
100nF                    103,4nF             103,7nF(.63)        105,2nF(7.28)
1µF                         988nF                973nF(.10)          1008nF(.77)
100µF                     95,4µF               93µF(.27)            86,27µF(.30)
10µF                      11,56µF              11,64µF(.83)       11,07µF(.84)
1000µF                  998µF                  976µF(.09)          923µF(.09)
470µF                     477nF                 471nF(.13)          454nF(.05)
2200µF                  2218µF                2120µF(.04)        1998µF(.06)
2200µF                  2126µF                2106µF(.09)         2005µF(.08)
100µF (400V)         100,4µF               99µF(.34)             95,78(0.33)
2200µF (old one)   2104µF                not checked          1945(.09)

82µF (100V)             78µF                  not checked           71µF (.06)

             


                 
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 26, 2018, 08:33:51 pm
I don't know why your tester reads larger caps a few percent low, but you could change the correction factor. Look for following lines in function LargeCap() in cap.c:
Code: [Select]
    if (Mode & PULL_10MS) Value /= 109;   /* -9% for large cap */
    else Value /= 104;                    /* -4% for mid-sized cap */

Large cap means capacitance > 47µF, and mid-sized cap 4.7 - 47µF. Simply lower the divisor to get a higher capacitance value.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dave356 on February 27, 2018, 05:11:09 am
Hi Guys,

I have a question on replacing the TL431 vref with the LM4040 in the mega328 kit.  I'm trying to remember from somewhere in this thread
if the 4040 is pin compatible with the 431.  Somethings telling me that it wasn't pin for pin.

I'm getting ready to assemble one of the kits, (have 2) but can't remember about the 4040.

Help will be appreciated,

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 27, 2018, 06:19:59 am
Hi Guys,

I have a question on replacing the TL431 vref with the LM4040 in the mega328 kit.  I'm trying to remember from somewhere in this thread
if the 4040 is pin compatible with the 431.  Somethings telling me that it wasn't pin for pin.

I'm getting ready to assemble one of the kits, (have 2) but can't remember about the 4040.

Help will be appreciated,

Thanks

(https://i.imgur.com/CWa4Aeq.jpg)

(https://i.imgur.com/RCDR6mw.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: RGK on February 27, 2018, 09:33:56 am
Hmmm, in that case I installed the LM4040 into my AT-AY incorrectly.  Post #4052 shows it correctly done?  Likely undamaged??

BK
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 27, 2018, 01:09:44 pm
And some good news ;) We proudly present 1.32m:
- Additional output of components found to TTL serial interface.
- Driver for TTL serial interface (hardware and bit-bang).
- Updated var_russian.h (thanks to indman@EEVblog).
- Added support for X&Y offsets to ST7735 driver.
- Changed configuration of battery monitoring. Added switches to disable battery monitoring and to support an unmonitored external power supply.
- Added configuration switch to reverse operation mode selection at startup (UI_AUTOHOLD).
- Improved filter for Germanium BJTs with high leakage current in detection function for depletion mode FETs.
- Added fancy pinout to PCD8544 driver. Also fixed error in the PCD8544 driver's function LCD_CharPos() for rotated output.
- Improved functions for fancy pinout of 3-pin semiconductors and moved some functions to display.c. Output of pinout on separate screen if required.
- Added indicator for usage of external voltage reference (Show Values).
- Improved IR decoder and added optional protocols.
- Added more protocols to IR RC transmitter.

And thanks to indman for the vintage Germanium BJTs.

Hi Markus, thank you so much for the new firmware!!!!
I quickly tested it mainly for the TTL Serial output implementation and even though I have several thinghs I would like to point out (I got use to the K-firmware serial output... :) ) I'm quite happy with it.
I enabled it via bitbanging on the M12864 banggood kit, and since I already wired it on PC3 as output I changed the pin assignements to use it and it works fine.

My main consern is that not everithing that I see on the LCD is sent to the serial port and when I enter the main menu nothing is sent to the serial output.
Only once I was able to see the menu on the serial but I can't replicate it.
BTW, at the end of each line of the menu a CR should be sent otherwise the menu appear as a long sentence.
On the k-firmware I discussed with karl-heinz a secondary option that send (only on the serial output) at the beginning of each line the number of display line that the text will be sent. This semplify alot the the interpretation of the strings by a companion software.

Great Job!!!
Mauro

Title: Re: $20 LCR ESR Transistor checker project
Post by: Miwer on February 27, 2018, 02:01:55 pm
Hmmm, in that case I installed the LM4040 into my AT-AY incorrectly.  Post #4052 shows it correctly done?  Likely undamaged??

BK

I can confirm post #4052 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1306279/#msg1306279). I installed it like that in my AY-AT, and it's working fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on February 27, 2018, 02:30:08 pm

I can confirm post #4052. I installed it like that in my AY-AT, and it's working fine.
[/quote]

How did you check it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 27, 2018, 03:22:20 pm
My main consern is that not everithing that I see on the LCD is sent to the serial port and when I enter the main menu nothing is sent to the serial output.
Only once I was able to see the menu on the serial but I can't replicate it.

This is intended. Just the welcome message, component founds and some error messages are copied to the TTL serial. Menus and tools are shown on the LCD only. I'm trying to add more features for the serial interface, but first I have to figure out what's feasible. 

If someone has problems with the bit-bang serial try to add a pull-up resistor (10k?) on the TX pin. While checking components the TX pin might be switched to HiZ. The pull-up resistor should provide the high level when idle.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Miwer on February 27, 2018, 05:06:16 pm
How did you check it?

Do you mean how did I figure it out?
Simply checking the datasheet for the two components. LM4040 and TL431 are NOT pin compatible. The anode and cathode are on different pins. Since the LM4040 doesn't have a REF pin, it doesn't matter where the third pin go since it's not connected internally anyway, and it's not needed for that part, so just match up the anode and cathode, and the last pin just goes in the remaining hole for the heck of it.  ^-^

If you mean how to verify it, then simply measure voltage on the ATmega pin 27 with a multimeter - it should be 2,5V when the device is on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: boffin on February 28, 2018, 05:21:31 am
And some good news ;) We proudly present 1.32m:
...
- Driver for TTL serial interface (hardware and bit-bang).
...

Awesome, and Vielen Dank


One thing I did wonder, is there a single page/wiki anywhere with all the details, notes etc etc?  Or just pull the tarballs and it's all in there?
Title: Re: $20 LCR ESR Transistor checker project
Post by: RGK on February 28, 2018, 05:23:52 am
Hmmm, in that case I installed the LM4040 into my AT-AY incorrectly.  Post #4052 shows it correctly done?  Likely undamaged??

BK

I can confirm post #4052 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1306279/#msg1306279). I installed it like that in my AY-AT, and it's working fine.

Just changed my LM4040 to look like post #4052 and (surprise!) now I get 2.5V on the atmega pin 27, vs. 5V before.  A bit embarrassing, but all good now.  Glad this came up and thanks!

BK
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on February 28, 2018, 09:16:23 am
The notes in the code by Markus are really well done and every change is pretty straight forword.

The change I made to enable the serial on my tester (see the first post in this page) are:

Uncoment the following lines in config.h

#define UI_SERIAL_COPY

#define SERIAL_BITBANG


In the config_328.h adjust the port/pin assignament as follow:

/* for hardware RS232 */
#define SERIAL_USART     0         /* use USART0 */
/* for bit-bang RS232 */
#define SERIAL_PORT      PORTC     /* port data register */
#define SERIAL_DDR       DDRC      /* port data direction register */
#define SERIAL_PIN       PINC      /* port input pins register */
#define SERIAL_TX        PC3       /* pin for Tx (transmit) */
#define SERIAL_RX        PD0       /* pin for Rx (receive, not supported yet) */

This will direct the serial output to PC3 pin on port C of the atmega microcontroller.

Mauro

Title: Re: $20 LCR ESR Transistor checker project
Post by: onre on March 01, 2018, 10:15:16 am
Hi, I am struggling to compile a correct firmware for a tester I got as a "try if you can make this thing work" kind of project. Apparently the tester has worked at some point, but as arrived it could turn on and after a long delay display random number characters on the screen.

It has an SMT Atmega 328P and the circuit board is marked as follows:

EZM Electronics Studio
MK-328 V1.10
2015.12.14

The display unit seems to be UC1701 based 128x64 display. I use an Arduino as programmer and can successfully flash and verify the MCU contents. However, I can't get the unit to do anything. Upon power-up, I get a blank lit-up screen which won't turn off. With some firmwares I can get some garbled screen output - just some pixels turned on, no legible characters. Unfortunately I accidentally deleted the stock firmware I had in a file, so I can't go back to that anymore, either.

Any ideas how to proceed? I've tried building different firmwares and can get some degree of response from hardware - screen contrast can be changed, and also different garbled patterns appear.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 01, 2018, 10:45:04 am
The UC1701 seems to be compatible with the ST7565, but I could be wrong. Have you also programed the EEPROM?
Title: Re: $20 LCR ESR Transistor checker project
Post by: onre on March 01, 2018, 10:52:19 am
The UC1701 seems to be compatible with the ST7565, but I could be wrong. Have you also programed the EEPROM?
Alright, thanks! I did program the EEPROM and have set the fuses as well to values found in this topic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: onre on March 01, 2018, 02:01:11 pm
Maybe the MCU is just partially burnt? I got to a point where I can enter the menus by the long button press. In the menus I can select the selftest, but end up with a flickering message telling me to "Short probes!", which I do, but the message does not go away.

edit: Additionally, the tester takes tens of seconds to get into the menus. I've checked fuses and used oscilloscope to confirm 8 MHz crystal frequency and no clock division.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 01, 2018, 06:31:08 pm
It could be a bad pin, but it could be also something else. Do you got another ATmega328?
Title: Re: $20 LCR ESR Transistor checker project
Post by: onre on March 01, 2018, 07:04:34 pm
Yes I do, but different form factor and I really don't want to solder SMT unless I have to. Also, because of typing error looks like I "fused myself out" (set the clock to the low frequency mode, can't read device signature anymore) so that's pretty much the end of the story.

However, the software seems so nice that we will order through-hole kits and build them in proper cases.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 06, 2018, 02:15:43 pm
I'm sorry to post such a n00b question. I'm new to embedded devices/micro-controllers. I have 2 of the AY-AT testers and I want to play around with the settings, install the latest firmware (both M and K). I want to try fitting an ST7735 screen to it also.

I'm not asking anyone to hold my hand per se. I'm a former developer so I can try to figure out the code. What I'm stuck with is how to most easily do this stuff on a Mac. I'd rather not run Parallels if I can avoid it. I have found a number of tools that may help, such as Atom with Platformio-IDE, Eclipse for C/C++, and MPLABX. Of course, I have seen avrdude to actually program the ATMega.

What I'm stuck with is how best to edit the appropriate files. I'm used to Xcode and Visual Studio where all files are accessible and you can just click "Build" or "Run" and voila! you have compiled code. With embedded, I have no idea how to begin.

Does anyone here use a Mac? What do you do to update the files and compile them for the LCR?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 06, 2018, 03:00:10 pm
I'm using a Mackbook to edit compile and load the firmware on my tester...

- Edit
  Plain and simple text editor

- Compile
  Installed CrossPack from https://www.obdev.at/products/crosspack/index.html (https://www.obdev.at/products/crosspack/index.html)
  I'm using this version:
  https://www.obdev.at/downloads/crosspack/CrossPack-AVR-20131216.dmg (https://www.obdev.at/downloads/crosspack/CrossPack-AVR-20131216.dmg)
  After you installed it:
  Open Terminal
  Go in the folder you have the ESR Transistor Tester firmware Makefile and type
  make all -f Makefile
  Just to be sure everything is working fine, do this without change any file just to see if it compile, then play with the editor...

- Programmer
   BusPirate

- Programming software Avrdude (also this is part of the CrossPack)
  I'm using this command to program the k-firmware
  avrdude -c buspirate -p m328p -B 0.5 -e -P /dev/cu.usbserial -b 115200 -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m
  I'm using this command to program the k-firmware
  avrdude -c buspirate -p m328p -B 0.5 -e -P /dev/cu.usbserial -b 115200 -U flash:w:"ComponentTester.hex":a -U eeprom:w:"ComponentTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

You will have to change only the programmer (if you dont have a BusPirate, I tryed also with an arduino as ISP, but almost everithing will do) and/or the serial name.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 07, 2018, 06:49:42 am
Does anyone here use a Mac? What do you do to update the files and compile them for the LCR?
https://jawher.me/2014/03/21/using-xcode-avr-c/
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 12, 2018, 08:15:44 pm
I've made some progress on the serial interface and got RX for the hardware based UART working. I think it should be possible to implement RX also for the bit-bang serial. Some users already suggested to add something like SCPI to control the tester. A driver for a serial driven HD44780 might be also an idea and would free up some MCU pins. I'm open for ideas about features using the serial interface.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 12, 2018, 08:28:32 pm
I can’t believe I didn’t reply. Thanks to @mauroh and @timelessbeing for your help!
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on March 13, 2018, 09:33:34 am
Sata conversion mk2. Mk 1 was 8-20V external powered with a dc-dc converter in the box.

Finally got around to squeezing a 2S LiPo 300mAh into my tester. No need for any battery BS saver the tester looks after that.

To save any whining the screws on the front are now black not stainless  :horse:  :-DD

3 pin lead set with header is handy too and fits in the bag.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 13, 2018, 04:51:40 pm
Post it here:

https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/ (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/)

It surely worth it  :-+

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 13, 2018, 04:59:56 pm
I can’t believe I didn’t reply. Thanks to @mauroh and @timelessbeing for your help!

You are welcome!! But the most important thing is... Was you able to compile the firmware?  :)
I like the idea of the XCode template linked by timelessbeing but havent tryed it yet.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 13, 2018, 07:53:45 pm
I can’t believe I didn’t reply. Thanks to @mauroh and @timelessbeing for your help!

You are welcome!! But the most important thing is... Was you able to compile the firmware?  :)
I like the idea of the XCode template linked by timelessbeing but havent tryed it yet.

Mauro
I’m still in progress, but I think I’m close! I’m looking at both options and experimenting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 18, 2018, 03:24:56 am
So after much playing around, I was finally able to get it to work. At least, I think so.

The biggest problem I had was getting an ATMel-ICE to work with my Mac. I'm going to buy the Adafruit programmer to make things easier in the future.

Everything seems to be working using the M-Firmware (thank you Markus!). The only think I notice is that it takes several seconds (with a white screen) before it shows the "Component Testor" wording. Then, I noticed that it doesn't always boot correctly. Sometimes, the white screen stays on. Sometimes, I have to hold the encoder button in order to get it to finally respond.

I'm guessing this has something to do with the fuses. I have tried the fuses: (E:FD, H:D9, L:F7) as well as (E:FD, H:D8, L:FF). I'm running a 16Mhz crystal.

Any further assistance is appreciated!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 18, 2018, 11:37:24 am
Maybe the BOD it's triggered. Do you got a DSO to monitor Vcc while powering on?
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 18, 2018, 01:42:18 pm
Maybe the BOD it's triggered. Do you got a DSO to monitor Vcc while powering on?

Yes, I have a scope, but I’m new to it. I’m powering the CT with a bench power supply, though so I know it is getting 9V. Maybe it needs more than 1A, though? The same problem occurs when using a 9V battery also.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 18, 2018, 03:34:53 pm
Vcc is the 5V rail (after the PNP transistor acting as a power switch and the 5V regulator).
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 18, 2018, 04:40:40 pm
Vcc is the 5V rail (after the PNP transistor acting as a power switch and the 5V regulator).

Okay. I’ll check it out and see what I can see.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 19, 2018, 06:16:11 pm
Only once I was able to see the menu on the serial but I can't replicate it.

Found the bug :) It's triggered when you enter the menu after no component was found or an error occurred. BTW, RX is also working in bit-bang mode now.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 19, 2018, 10:57:09 pm
Thank you, madires!

I'm not sure I'm doing this correctly. I'm attaching a diagram of the board with the Voltage readings from my DMM. I'm also attaching a screenshot from my scope measuring at the NPN. If I haven't done something correctly with the scope, it's because I'm totally new to them. If you need any other type of view, please let me know and I will try again.

Thanks,

Jonathan
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 19, 2018, 11:32:43 pm

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=405263;image)

I’m powering the CT with a bench power supply

I'd say your power supply is pooched
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 19, 2018, 11:41:31 pm
I may not be using the scope correctly. I really have no idea what I'm doing. It's a Rigol MSO2102A. I have calibrated the probes, but that is it. I literally have never used a scope before. This is my literal first attempt at using it.  :-[ :)

I'm guessing that I'm not connecting the ground wire in the right place or that there is a setting on the scope that I just don't have set up correctly for this type of measurement.

When I use the DMM, it reads near-perfect 9V at the source and near-perfect 5V at the transistor. The power supply is a brand new Rigol DP832.

Perhaps it would be important for me to tell everyone that both the DP and the MSO have been unlocked to their full potential.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 19, 2018, 11:49:20 pm

I'm guessing that I'm not connecting the ground wire in the right place
Put the probe ground clip on negative supply, and the touch the probe tip to the same place you put your DMM. Also try probing Vcc at the ATMEGA328 pin 7

The tester should draw significantly less than 1A.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 19, 2018, 11:58:08 pm

I'm guessing that I'm not connecting the ground wire in the right place
Put the probe ground clip on negative, and the touch the probe tip to positive.

LOL. I knew that much. What I didn't know is if it makes a difference which negative (where) on the board that I use. I used the one at the battery connector because it was easily available.

Are there settings on the MSO2102A (or a typical) scope that I need to be mindful of in order to take the measurement for DC?

I'm guessing that my Fluke 289 is not lying about the voltage being 9V (before the transistor) and 5V (after the transistor). So, it doesn't make sense that the scope is showing what it is showing. I thought the more likely scenario is that I'm using it incorrectly somehow.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 20, 2018, 12:03:55 am
What I didn't know is if it makes a difference which negative (where) on the board that I use. I used the one at the battery connector because it was easily available.
It's a common negative circuit, meaning it should be the same everywhere, so yes the battery connector is as good a place as any.

Are there settings on the MSO2102A (or a typical) scope that I need to be mindful of in order to take the measurement for DC?
Just choose a good timebase that will allow you to see the whole power-on transition. Or you could AC couple your scope, and use a single shot capture , triggered on a voltage rise of a volt or so.

I have no idea why your scope is showing a 3.3V sinusoidal waveform at mains frequency. Some kind of diagnostic function?
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 20, 2018, 02:19:37 am
I don't know why it was showing a sine wave either. But, I did some poking around. For some reason, on the AY-AT board (or mine at least), the negative terminal on the battery connector is NOT a good place to put the ground for the scope. I think the DC connector has some sort of disconnect when something is plugged into it? Makes sense, perhaps, so that you aren't powering it both from an external DC supply AND a battery at the same time. 9V + 9V = bad.

Once I figured out how to use the trigger function, I was able to get valid readings. See attached. What you are seeing in terms of the change in voltage is when I touch the probe to the NPN. This is after the AY-AT is already on (I can tell by the red LED).

I'm truly sorry for my n00bness, but I do appreciate all the help!  ;D

What I'm guessing you need, however, is a trigger NPN at the time that the decoder is pressed. Is that correct? If so, that is proving difficult to accomplish logistically as I have to manually hold the probe in place on the bottom of the board. How does one set up the probes to that they stay in place while an external, manual, mechanical trigger is applied? I have nothing for the alligator clip and probe grabber to clip on to. Should I attach something to the solder joints temporarily for testing purposes?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 20, 2018, 02:48:37 am
<EDITED> misread previous post.

Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 20, 2018, 02:54:25 am
I have nothing for the alligator clip and probe grabber to clip on to. Should I attach something to the solder joints temporarily for testing purposes?

If needed, you can always temporarily solder wire(s), clip onto them, take measurements, and then desolder the wire(s) when done.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 20, 2018, 11:35:30 am
Only once I was able to see the menu on the serial but I can't replicate it.

Found the bug :) It's triggered when you enter the menu after no component was found or an error occurred. BTW, RX is also working in bit-bang mode now.

Hi Markus, thank you for looking at it  :-+
In the mean time I've noticed another small issue, possibly related to this bug:
If I try to measure a 3 pin component that happen to be a dead short, instead of measuring it as 2 small resistors, it enters the menu.
Is this by design?
Can I try the serial RX? Are you defining a series of command we can send to manipulate the tester?
Mauro

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 20, 2018, 02:44:09 pm
Hi Mauro!

In the mean time I've noticed another small issue, possibly related to this bug:
If I try to measure a 3 pin component that happen to be a dead short, instead of measuring it as 2 small resistors, it enters the menu.
Is this by design?

Yes, it's a feature, not a bug ;) Originally this was the only way to enter the menu before we added the option to enter the menu also by the test push button. And the self test and self adjustment require shorted probes anyway. But I agree, it can be confusing in some cases. Maybe it's time to remove this feature. What do you and other users think about this?

Can I try the serial RX? Are you defining a series of command we can send to manipulate the tester?

At the moment the tester simply echos the serial input back to the PC while managing a small receive buffer. The next step is to figure out what kind of commands would be useful for automation. Any suggestions are welcome.

PS: the results of the optocoupler check will be put out via the serial interface too

Cheers,
 Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on March 20, 2018, 04:28:08 pm
Make sense  :-+, but I can't speak for others because I enter the menu only rotating the encoder and dunno what this will impact on the testers with just the botton.
Regarding the serial output, at the moment I'm using it (with the k-firmware) to replicate the display content on a desktop monitor and with a bit of parsing to log each measure. This is part of a super easy test jig at work and I can say that it was good to have all the content of the LCD always also logged (identify human errors...).

It should be also useful to start a measure or a enter in a menu with a command and get the result also on the serial output.
In this case I think it should be better to select if we want a single measure or a continues cycle.

Just my 2 cents  :popcorn:

Mauro

BTW As always...Thank you so much
Title: Re: $20 LCR ESR Transistor checker project
Post by: nation on March 23, 2018, 06:08:14 am
Hi All, first post.

Sorry if this post sounds daft but I'm a rank amateur with this stuff (I'm just looking to test some germanium transistors for guitar pedals).

I just ordered a GM328A off ebay and I received it today. I have tried powering it up with both a 9v battery and a power supply. When I press the rotary button nothing happens, no LED lights, the screen doesn't turn on. Is there some sort of rain dance I need to do before the unit works or do I just have a faulty unit?

This is the unit I bought https://bit.ly/2pzHQI3.


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 23, 2018, 10:17:13 am
Welcome! I like the idea of the rain dance but your tester seems to be simply DOA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on March 23, 2018, 07:30:52 pm
Hi All, first post.

Sorry if this post sounds daft but I'm a rank amateur with this stuff (I'm just looking to test some germanium transistors for guitar pedals).

I just ordered a GM328A off ebay and I received it today. I have tried powering it up with both a 9v battery and a power supply. When I press the rotary button nothing happens, no LED lights, the screen doesn't turn on. Is there some sort of rain dance I need to do before the unit works or do I just have a faulty unit?

This is the unit I bought https://bit.ly/2pzHQI3.
Program the 328 thing then redo the rain dance :)


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on March 23, 2018, 09:09:05 pm

The next step is to figure out what kind of commands would be useful for automation. Any suggestions are welcome.


Having some SCPI-like commands would be great. "READ" for numerical data, "COMP" for component and "UNIT" for
unit of measurement would be nice to start with.

I did write some Profilab programs for the GM 328 Transistor tester. But since formatting is different for each component
and dependent on the type of display, I had to write a separate program for each component.
Because formatting is also dependent on the specific firmware, keeping the programs up to date for the GM 328
alone is tedious (and boring). Thus having a few commands would simplify programming very much so that I 
would be prepared to resume Profilab programming for the Transistor Tester - regardless of type.

Title: Re: $20 LCR ESR Transistor checker project
Post by: nation on March 23, 2018, 11:41:15 pm
Hi All, first post.

Sorry if this post sounds daft but I'm a rank amateur with this stuff (I'm just looking to test some germanium transistors for guitar pedals).

I just ordered a GM328A off ebay and I received it today. I have tried powering it up with both a 9v battery and a power supply. When I press the rotary button nothing happens, no LED lights, the screen doesn't turn on. Is there some sort of rain dance I need to do before the unit works or do I just have a faulty unit?

This is the unit I bought https://bit.ly/2pzHQI3.
Program the 328 thing then redo the rain dance :)


Envoyé de mon iPad en utilisant Tapatalk

Thanks perieanuo but how do I program it? Is there any instructions for this online?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 24, 2018, 12:08:18 am
Scan back a few pages. Instructions for programming the more common versions are repeated in this thread from time to time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 25, 2018, 12:59:42 am
I wanted to report back to everyone. Thank you again to everyone for their help!

I have been able to compile 1.32m for a while, but was having trouble with the tester itself. The scope showed nothing revealing even with the solder points. Still didn't work correctly.

I have been messing around with it and decided to try a different programmer. I got an Adafruit USBtiny. I sent it the firmware and it worked the first time!

For whatever reason, the Atmel-Ice would just not program the 328p reliably on my Mac. But, the Adafruit worked right off the bat!

Perhaps it was an issue with AVRdude, but I'm not going to question it. Everything appears to be working!
Title: Re: $20 LCR ESR Transistor checker project
Post by: technogeeky on March 25, 2018, 03:24:08 am
I don't know why it was showing a sine wave either.

Enjoy the oscilloscope. If you see a sine wave, and it's 60 Hz, then you're seeing inductive (or capacitive, but probably inductive) coupling into your probe. Mains AC couples into everything. This showing up on your scope is a consequence of its very high input impedance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 25, 2018, 04:14:15 am
at 7V P-P?  Pretty strong for induction isn't it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: guy232 on March 26, 2018, 01:11:47 pm
I have spent a few hours attempting to search for answer but seem to be overlooking it.

I read that not all of these mega328 lcr testers are capable of using the M-Firmware? Is there a way to determine which variants of this tool support the M-Firmware? Or is there a most popular variant of this device, I havent had success finding it in these pages.

Thanks for your time!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 26, 2018, 04:16:19 pm
Most clones are supported by both firmwares (k & m). As long as the circuit follows the basic design it should work fine. One problematic clone is the TC-1 which uses an additional MCU for power control and test button. That hasn't be reversed engineered yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TechieTX on March 27, 2018, 02:47:47 am
Odd observation...
I've been using an AY-AT with the accuratizing parts and 1.13K for a couple of weeks while I tried to figure out how to build the 1.32m firmware.  Building 1.32m was WAY more painful than it needed to be!  Anyhow, the 1.13K has worked fine on everything I've tried, and it identified some bad 20-year-old MOSFETs I'd been keeping for future projects.  Finally this evening I worked out the last of the problems with building 1.32m and started testing, after calibrating it.  Mostly OK, although I noticed it's more variable on repetitive readings on many of my ceramic caps.  A quality film cap might read 960-963pf, but a ceramic would read anywhere from 9616pf to 10.7nf (about a 10% total range), and it never stabilized.  Aluminum electrolytics and tantalums?  Still within < 1% range on successive reads, but the ceramics I have are all over the map.  1.13K with that same 10nf ceramic only hit a range of 10.06 to 10.16, or around 1% variance with multiple measurements.

Looking at the results after adjustment, that VCC is wrong.  1.13K is reporting 5.00V for VCC and my Fluke and Wavetek DMMs both read 5.00V; that 5.025 reading may have something to do with the inaccuraty.  I haven't tried recompiling to use the LM4040AIZ reference yet; that may cure the issues with the ceramics and/or varying results.  I'd left it remarked due to comments about the external ref being useless if you have a precision LDO regulator.  Maybe not so much.

(https://i.imgur.com/9aKIXfu.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 27, 2018, 09:11:11 am
Didn't the settings listed in the Clones file work? If so, please PM your settings for updating the file. The asterisk after Vcc indicates that an external reference is used. Since Vcc is exactly 5V please disable HW_REF25 and try the ceramic caps again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: VEGETA on March 28, 2018, 08:14:46 pm
So what is the latest\best version of this thing? I know the banggood one is famous, is it the one?

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 28, 2018, 10:38:49 pm
So what is the latest\best version of this thing? I know the banggood one is famous, is it the one?

It's hard to tell with some of them. Look for ones that specifically say AY-AT on the board. However, one of the ones that I bought showed AY-AT in the photo, but not on the actual board when it arrived. It looks the same to me, but I wonder if it is somehow inferior. But, you are looking for the one with the 3 wire terminals and the rotary encoder. Those are the latest boards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TechieTX on March 29, 2018, 01:53:21 am
Well, I've beat it to death by now, and got everything in 1.32m to compile without any horseplay.  Something had been enabled that was sending out a 5us HIGH pulse on PD3, which wiped out reading the encoder (see the photo of the PD3 pin).  I worked back and forth between the (heavily modified) config.h and config_328.h I got working compared to the distribution file and got it going without much modification.  The ZIP file has the Makefile, config.h and config_328.h for the AY-AT with the precision LDO and resistors and the original 8MHz crystal.  I've only tested the compile with WinAVR as that's all I have installed.

I still get erratic readings (10% variance) with cheap ceramic caps, stable with mica, film, aluminum electrolytics and tantalums, so I'm OK with it having 10% variation on cheezy caps that have over 110 ohms ESR.  The other features that I tested work fine, so it's a GO for me.  I did disable the 2.5V reference chip, and it didn't make any difference.  I'd added some extra grounding to my board since the layout for ground is absolutely pitiful, but removing my extra grounds didn't change anything.

I modified the Makefile to use my USB ASP programmer under WinAVR; your configuration may vary.  I used the -F switch (ignore ID bytes) with avrdude 'cos most of my testing was with an ATMEGA328 (no P), but the code works with 328 or 328P, no difference as far as I could tell.  The last two pics are after an adjustment cycle with both 328 and 328P.

One suggestion: change the configuration in your standard config_328.h file to match the clone settings for the AY-AT.  The default settings won't run the ST7735, which causes trouble for anyone with an AY-AT.  Since it's the most popular board with that display, it makes sense to have the defaults match the AY-AT.  Fewer complaints of "I did the build and my display doesn't work!" is a Good Thing.  ;)  I'd also recommend the #define ENCODER_A        PD2 to be #define ENCODER_A        PD1 for the same reason.  If > 70% of the people here are using an AY-AT, then the defaults in the code should match the most common configuration. (I'm guessing on that 70% from the posts over the last 8 months).

EDIT:  I recompiled for 16MHz and inserted a 16 meg crystal, and the inaccuracy with the ceramics doesn't happen, for whatever reason.  The readings are stable, and roughly the same as what I remember Karl-Heinz' version reading.  I'll do 1.13K next with the 16M crystal and update the results.
Update twice: I had to gut the menu out of 1.13K 'cos it was compiling to 112% of flash, and I couldn't find the wasted space where the bootloader was being added in.  It was also unstable with the cheap ceramic caps at 16MHz, although Karl-Heinz did say that measurement accuracy would be effected in his code with a 16MHz crystal.

Thanks for all your work, everyone!
Title: Re: $20 LCR ESR Transistor checker project
Post by: VEGETA on March 29, 2018, 07:28:26 am
Quote
I modified the Makefile to use my USB ASP programmer under WinAVR; your configuration may vary.

Where are the files hosted? I didn't think it is true open source though.

Quote
It's hard to tell with some of them. Look for ones that specifically say AY-AT on the board. However, one of the ones that I bought showed AY-AT in the photo, but not on the actual board when it arrived. It looks the same to me, but I wonder if it is somehow inferior. But, you are looking for the one with the 3 wire terminals and the rotary encoder. Those are the latest boards.

I was speaking about this one:
https://www.banggood.com/DANIU-3_5inch-Colorful-Display-Multi-functional-TFT-Backlight-Transistor-Tester-p-1083042.html (https://www.banggood.com/DANIU-3_5inch-Colorful-Display-Multi-functional-TFT-Backlight-Transistor-Tester-p-1083042.html)

I cannot tell if it is latest edition but it has nice enclosure which is important for me. ZIF socket is there as well.

There is this one too:
https://www.aliexpress.com/item/Multi-purpose-Transistor-Tester-128-160-Diode-Thyristor-Capacitance-Resistor-Inductance-MOSFET-ESR-LCR-Meter-TFT/32812264664.html (https://www.aliexpress.com/item/Multi-purpose-Transistor-Tester-128-160-Diode-Thyristor-Capacitance-Resistor-Inductance-MOSFET-ESR-LCR-Meter-TFT/32812264664.html)

But I don't know which one is better as there is no comparison sheet between them. I wish someone makes a shootout for these.

It is worth mentioning that there is this one too for SMD components:

https://www.banggood.com/BSIDE-ESR02PRO-Digital-Transistor-SMD-Components-Tester-Diode-Triode-Capacitance-Inductance-Meter-p-1218985.html (https://www.banggood.com/BSIDE-ESR02PRO-Digital-Transistor-SMD-Components-Tester-Diode-Triode-Capacitance-Inductance-Meter-p-1218985.html)

Eventually, we are lucky to have such very cheap good and working devices. Otherwise, we'll be paying $$$.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on March 29, 2018, 11:43:46 am
Quote
I modified the Makefile to use my USB ASP programmer under WinAVR; your configuration may vary.

Where are the files hosted? I didn't think it is true open source though.

Files are here and are open source: https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)


I was speaking about this one:
https://www.banggood.com/DANIU-3_5inch-Colorful-Display-Multi-functional-TFT-Backlight-Transistor-Tester-p-1083042.html (https://www.banggood.com/DANIU-3_5inch-Colorful-Display-Multi-functional-TFT-Backlight-Transistor-Tester-p-1083042.html)

I cannot tell if it is latest edition but it has nice enclosure which is important for me. ZIF socket is there as well.

There is this one too:
https://www.aliexpress.com/item/Multi-purpose-Transistor-Tester-128-160-Diode-Thyristor-Capacitance-Resistor-Inductance-MOSFET-ESR-LCR-Meter-TFT/32812264664.html (https://www.aliexpress.com/item/Multi-purpose-Transistor-Tester-128-160-Diode-Thyristor-Capacitance-Resistor-Inductance-MOSFET-ESR-LCR-Meter-TFT/32812264664.html)

But I don't know which one is better as there is no comparison sheet between them. I wish someone makes a shootout for these.

It is worth mentioning that there is this one too for SMD components:

https://www.banggood.com/BSIDE-ESR02PRO-Digital-Transistor-SMD-Components-Tester-Diode-Triode-Capacitance-Inductance-Meter-p-1218985.html (https://www.banggood.com/BSIDE-ESR02PRO-Digital-Transistor-SMD-Components-Tester-Diode-Triode-Capacitance-Inductance-Meter-p-1218985.html)

Eventually, we are lucky to have such very cheap good and working devices. Otherwise, we'll be paying $$$.

I didn't realize you were asking about a completed product to purchase rather than a DIY version of the tester. I don't know if anyone can give you the information you are seeking for pre-built testers. To me, it appears that many companies are making them so you can't be guaranteed even which one you will get other than that they will look the same. However, the quality of the parts inside could be very different.

I'm not saying that those testers are bad, but you may not know what you are getting until you receive it. My conclusion when it came time for me to buy one was to build my own because that would be the only way I could make sure I was using quality parts. The resistors, voltage reference, and a couple other parts are crucial to having a good tester. It took me a long time, but I finally have one that appears to work very well.

The testers you have linked to do not have any rotary encoder so they would not be the latest iteration of the tester. However, if you really want to buy a pre-built tester, you should look for one that looks like the one attached below.

This layout has a rotary encoder, ZIF socket, 3 wire terminals, and SMD tester. I have not seen one like this that comes in a more polished, more commercial-style enclosure, but you can find them on eBay and other sites pre-built with an acrylic enclosure. For example: https://www.ebay.com/itm/Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-Signal-Generator-MOS-Triode-/172845809087 (https://www.ebay.com/itm/Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-Signal-Generator-MOS-Triode-/172845809087)

The downside to many of the enclosures I have seen and actually tried is that some of them don't leave enough room to use the ZIF socket lever easily and cover up the SMD tester if that is important to you.

As for the shootout idea, while it would be great, I don't think it is possible because you never know which company made the tester just from the web site. I would be wary of buying one pre-made. You may find that to get good testing results, you have to tear it apart and replace various parts anyway.

I hope this helps.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Twenty4Pack on March 29, 2018, 02:47:15 pm
Quick comment on the ZIF:  I put a short length of heatshrink tubing on the ZIF bar - left the end on - to get around the acrylic cover's interference issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lypse on April 01, 2018, 02:09:14 pm
Hi guys,

I am wondering, is it possible to buy an official tester with good parts and decent case recent firmware ect..? :)

I don't mind soldering if its sold as a kit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 01, 2018, 05:14:40 pm
There isn't any official model, but the AY-AT type clones are nice.

Quick update on the m-firmware: The framework for a very simple command parser is done.
Title: Re: $20 LCR ESR Transistor checker project
Post by: VEGETA on April 03, 2018, 09:12:04 am
Hi guys,

I am wondering, is it possible to buy an official tester with good parts and decent case recent firmware ect..? :)

I don't mind soldering if its sold as a kit.

I want that too, since the ones in Banggood and Aliexpress have nice enclosure.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 03, 2018, 06:18:26 pm
Having occasionally seen posts requesting a high quality, tested, and/or fully featured version of this tester, I'm curious what kind of price would be acceptable to those who want them. A kit or even fully assembled tester with nice case can certainly be made. It's not a technical hurdle. But making them in small quantities will cost much more than the typical ones that can be ordered from China.

I haven't done a cost analysis to know what such a tester would actually cost to make. Hypothetically, though, instead of being $10-20, if a "good" tester cost $50, $75, or even $100, would that still be desirable or would you just purchase an existing commercial tester (many of which don't have as much functionality in a single device)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: lypse on April 03, 2018, 06:33:22 pm
I guess at 100$ it should feel like a similar priced multimeter, case, button, screen, test leads and so on.. maybe styled as one of the cute pocket meters?

at 50$ it should be like the current clones with a "decent" case, but good components

Firmware updates should not require much coding skills if any.. ;) (unless the user wanted to)

Where would I see the AT-AY testers mentioned? is it the version with output terminals and rotary encoder?

Having occasionally seen posts requesting a high quality, tested, and/or fully featured version of this tester, I'm curious what kind of price would be acceptable to those who want them. A kit or even fully assembled tester with nice case can certainly be made. It's not a technical hurdle. But making them in small quantities will cost much more than the typical ones that can be ordered from China.

I haven't done a cost analysis to know what such a tester would actually cost to make. Hypothetically, though, instead of being $10-20, if a "good" tester cost $50, $75, or even $100, would that still be desirable or would you just purchase an existing commercial tester (many of which don't have as much functionality in a single device)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 03, 2018, 06:59:29 pm
I guess at 100$ it should feel like a similar priced multimeter, case, button, screen, test leads and so on.. maybe styled as one of the cute pocket meters?

That makes sense from the customer's perspective. I wonder, though, what the required manufacturing volume would be to be able to accomplish it. Likely quite a financial commitment.

Quote
at 50$ it should be like the current clones with a "decent" case, but good components

That sounds like a feasible middle ground that might be able to be accomplished without major upfront capital investment.

Quote
Firmware updates should not require much coding skills if any.. ;) (unless the user wanted to)

I'm not sure how much additional hardware and/or software would be required to be able to update it without installing dev tools, hooking up an ICSP cable, etc. It would be a worthy enhancement from a product perspective, though.

Quote
Where would I see the AT-AY testers mentioned? is it the version with output terminals and rotary encoder?

By "mentioned," do you mean how do you make a positive identification? The "AY-AT" lettering is generally silkscreened in small font near one of the edges of the PCB with some other identifiers. The ones I usually see use a red PCB with three separate two-pole terminal blocks and rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on April 03, 2018, 07:13:38 pm

I'm not sure how much additional hardware and/or software would be required to be able to update it without installing dev tools, hooking up an ICSP cable, etc. It would be a worthy enhancement from a product perspective, though.


Fairly trivial if it includes a serial port and bootloader...
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 03, 2018, 09:40:27 pm
Yeah, it'd need space for a bootloader. The 328 is full with all that's possible in the m firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on April 03, 2018, 10:47:35 pm
Yeah, it'd need space for a bootloader. The 328 is full with all that's possible in the m firmware.
Methinks that the biggest issue for a newbie is figuring out how to build and which binary to flash.

If someone were to make a ready-to-go version and provide a single repository of binaries, ready to be flashed with a USBASP, the issues that most new users face would almost completely disappear. Provide a simple set of flashing instructions for a specific board, and a repository with the latest, tested binary for that

IMHO, a bootloader would not be the most critical element. The main challenge for someone new is figuring out what binary is safe to flash, given the immense variety of boards and firmware combinations
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on April 03, 2018, 11:09:57 pm
If someone were to make a ready-to-go version and provide a single repository of binaries
You mean, like on the very first page?

Message #4
 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg195143/#msg195143)
Flashing instructions should be all over the internet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: VEGETA on April 04, 2018, 05:46:20 am
current "clones" are ok but you here have latest firmware so that is the addition, not to mention better parts. So the enclosure is the same while the firmware is updated.

If it was 30-40$ only then it would be nice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 04, 2018, 09:55:03 am
Yeah, it'd need space for a bootloader. The 328 is full with all that's possible in the m firmware.

Karl-Heinz has modified optiboot to program the EEPROM too (the original version does only the flash memory): https://github.com/svn2github/transistortester/tree/master/bootloaders. And the ATmega644/1284 based tester with more flash and I/O pins allows us to have a dedicated hardware USART. Possibly will see a tester with bootloader in the future ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 04, 2018, 10:20:39 am
IMHO, a bootloader would not be the most critical element. The main challenge for someone new is figuring out what binary is safe to flash, given the immense variety of boards and firmware combinations

Karl-Heinz already offers compiled firmware (k-firmware) for a bunch of different tester models. For the m-firmware there's the Clones file which lists the settings for a few models. If you got a tester not listed please send me your working settings and I'll update the file. We try to provide support for most models, but we're also just humans with limited resources. Maybe I've given you an idea on how to help ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on April 04, 2018, 12:36:03 pm
Having built a couple of these already, I think it would be a challenge for someone to build an affordable device, with an enclosure and appropriately spec’d components. For example, the high-quality resistors for the testing portion of the AY-AT circuit total $8 all by themselves (full retail, of course). The reference voltage transistor is $1.72. That’s already $10 in parts.

It seems to me that unless these things are built in seriously high volume, it would not be possible to build a quality kit or completed product including a nice enclosure for even $50 with a decent profit margin.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on April 04, 2018, 03:14:04 pm
IMHO, a bootloader would not be the most critical element. The main challenge for someone new is figuring out what binary is safe to flash, given the immense variety of boards and firmware combinations

Karl-Heinz already offers compiled firmware (k-firmware) for a bunch of different tester models. For the m-firmware there's the Clones file which lists the settings for a few models. If you got a tester not listed please send me your working settings and I'll update the file. We try to provide support for most models, but we're also just humans with limited resources. Maybe I've given you an idea on how to help ;)

I know, and I found everything I need :) thanks to all the folks who did the work. But, based on the questions in the long thread, there are many people who have problems finding "the right" device to buy and then struggle figuring out which binary to flash. Unless you are 100% sure that you have the right build for a device, there's always a risk that flashing it would make it inoperable. I bought a blank 328p to flash, just to be on the safe side and be able to go back to factory image if needed, even if I was pretty confident

My point was that, if anyone were to offer a pre-assembled device with a simple repository of builds (actually, just one or two), it would go a long way towards solving the problem. Going ever further and offering a bootloader (which is what I was replying to) won't offer that much more value

The real problem, as others are pointing out, is that any decent quality kit, once the cost of the better components, assembly and shipping are taken into account, would be too expensive for most users (or has to be sold at cost, making it a bad proposition for whoever assembles it)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 04, 2018, 05:13:26 pm
Yeah, it'd need space for a bootloader. The 328 is full with all that's possible in the m firmware.

Karl-Heinz has modified optiboot to program the EEPROM too (the original version does only the flash memory): https://github.com/svn2github/transistortester/tree/master/bootloaders. And the ATmega644/1284 based tester with more flash and I/O pins allows us to have a dedicated hardware USART. Possibly will see a tester with bootloader in the future ;)

Ah, I didn't know about the optiboot. I was thinking more about the larger ATmegas as you mentioned (644, 1284, 2560, etc.).
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 04, 2018, 05:17:15 pm
Having built a couple of these already, I think it would be a challenge for someone to build an affordable device, with an enclosure and appropriately spec’d components. For example, the high-quality resistors for the testing portion of the AY-AT circuit total $8 all by themselves (full retail, of course). The reference voltage transistor is $1.72. That’s already $10 in parts.

It seems to me that unless these things are built in seriously high volume, it would not be possible to build a quality kit or completed product including a nice enclosure for even $50 with a decent profit margin.

Exactly. Just guesstimating, even at modest volumes for parts, yields a pretty high overall cost. That's why I was just wondering what people's expectations were as far as price. Such an endeavor is only feasible if the market can bear it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 04, 2018, 05:32:09 pm
My point was that, if anyone were to offer a pre-assembled device with a simple repository of builds (actually, just one or two), it would go a long way towards solving the problem.

So, something like order a batch of a particular model (e.g., AY-AT) from China (hopefully, at a discount) to resell with a case and CD of the latest k and m firmware (binary and source) for it (and/or flash it with the latest).

Quote
The real problem, as others are pointing out, is that any decent quality kit, once the cost of the better components, assembly and shipping are taken into account, would be too expensive for most users (or has to be sold at cost, making it a bad proposition for whoever assembles it)

Yeah, which is likely the reason it's not been done. I'm still amazed that the companies in China are willing to make it available so inexpensively since it's pretty niche.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Argiros on April 05, 2018, 02:21:14 am
Dear friends, finally after a long time and when the mc ATMega328p came for my bricked GM328B, I desolder as I promised the smd mc and put a  new one and everything was ok! Also I managed to program it to new versions for ex v1.29 by Markus (amazing  compared to my original crappy one) and I also put from Karl  the Mega328_colorkit version for testing it. Although I have and the good rotary GM328A version board, but I like more to play with the GM328B. This B model has 2 buttons only and it is pathetic. The one btn is the reset and doing only reset, and the other is the select button. To getting to the menu to selecting items and to get back is impossible like the rotary one. 
      And here is my question :

Can I add a rottary switch button to this model GM328B ? Where I can solder this ?

or else can I add 3 more buttons for using them for scrolling up down and for back ?

I use avr-gcc ver 4.9. Which compiler version is the best because the older makes big files and the newer are making errors. Is there any other compiler - program better ?

Thank you all for your help and a very big THANK YOU to our leader MADIRES!  :-+ you are the best man!
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on April 05, 2018, 06:06:51 am
Karl's documentation has schematics which show how you can connect a rotary encoder. The documentation is pretty much required reading for anybody wanting to make modifications.

GCC problems (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1135568/#msg1135568).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 05, 2018, 10:19:04 am
Can I add a rottary switch button to this model GM328B ? Where I can solder this ?

or else can I add 3 more buttons for using them for scrolling up down and for back ?

You can use two push buttons for up/down (increase/decrease) instead of a rotary encoder (k-firmware: WITH_ROTARY_SWITCH 4, m-firmware: HW_INCDEC_KEYS, and check the portpins). The test button is mandatory, either as a separate push button or integrated in the rotary encoder. And there's no back button. As timelessbeing already has mentioned, the wiring is explained in Karl-Heinz' documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on April 06, 2018, 04:47:20 pm
Hi,
is there firmware with support for  STE2007 96 x 68 Single Chip LCD Controller/Driver ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 06, 2018, 06:17:21 pm
No, the STE2007 isn't supported. But based on the datasheet it shouldn't be hard to write a driver.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Argiros on April 12, 2018, 09:55:20 am
<madires>: Are you saying that I cannot add a rotary button but only the 2 buttons ? or I can add them either one or the other ? or maybe both rotary and buttons ?

I think I found some of the answers through Karls doc:
this schematic is explaining much. The only thing I dont know yet is if I can use both rotary and buttons through software issues.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2018, 10:45:02 am
k-firmware: You can add either a rotary encoder or two push buttons (up/down).
m-firmware: You can add a rotary encoder, two push buttons (increase/decrease) and a touch screen. Usually you would add only one because the ATmega328 doesn't provide enough I/O pins and all three do the same - just in a different way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 12, 2018, 12:39:39 pm
Hello Everyone,

I bought 2 of the attached tester and installed the M version on one and the K version on the other. The one with the K version burnt the chip (v05 - diode array) and then the main chip. Should I be modifying it to use the K version? Also, with the M version, if there is nothing in the tester it gives me a reading of a capacitor of 15 pf, but seems to work ok otherwise.

I installed the latest version for both firmwares.

Any help would be appreciated. This model has the input protection circuit as you can see on the back.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2018, 01:23:28 pm
I think I found some of the answers through Karls doc:
this schematic is explaining much. The only thing I dont know yet is if I can use both rotary and buttons through software issues.

The rotary encoder and the alternative two push buttons are wired exactly the same way. With the k-firmware you can have only one of both. Anyway, it doesn't make much sense to have both because they provide the same function (up and down). Also the ATmega328 doesn't have enough I/O pins for connecting both. If you prefer push buttons over a rotary encoder then choose the push buttons, or vice versa.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2018, 01:44:43 pm
I bought 2 of the attached tester and installed the M version on one and the K version on the other. The one with the K version burnt the chip (v05 - diode array) and then the main chip. Should I be modifying it to use the K version? Also, with the M version, if there is nothing in the tester it gives me a reading of a capacitor of 15 pf, but seems to work ok otherwise.

A few users with the kit version of your tester had problems with the placement of the SRV05-4. When reversed the internal TVS diode will short Vcc to ground. Since it's an optional (weak) input protection the tester will also work without it. After programming the firmware please run the self-adjustment and the 15pF issue will vanish.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 12, 2018, 06:43:44 pm

[/quote]

A few users with the kit version of your tester had problems with the placement of the SRV05-4. When reversed the internal TVS diode will short Vcc to ground. Since it's an optional (weak) input protection the tester will also work without it. After programming the firmware please run the self-adjustment and the 15pF issue will vanish.
[/quote]

Hello Madires,

Are you saying that I could simply remove the SRV05 and work it that way? This was not a kit version, so I didn't install it.  But if you are saying that it is almost useless, then I will simply remove it. Please confirm and tks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2018, 06:50:05 pm
The SRV05-4 isn't useless but the tester works also fine without it. Make sure you discharge any capacitor before testing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TechieTX on April 13, 2018, 01:04:53 am
I use one of the surface-mount test pads to discharge caps on the AY-AT.  They're a handy bit of metal near the ZIF socket.  Of course be careful to hit only ONE of the pads with both legs of the cap, or POOF! goes your tester.  Several other boards have something similar you can use.

(https://i.imgur.com/DlvDh8Z.jpg)

I discharge all caps (regardless of type or 'built-in protection' on the board) as I've seen a number of folks complain that they've fried their tester.  My ATmega is socketed, but I don't have an endless supply of them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on April 13, 2018, 01:41:22 am
I use one of the surface-mount test pads to discharge caps on the AY-AT.  They're a handy bit of metal near the ZIF socket.  Of course be careful to hit only ONE of the pads with both legs of the cap, or POOF! goes your tester.  Several other boards have something similar you can use.

(https://i.imgur.com/DlvDh8Z.jpg)

I discharge all caps (regardless of type or 'built-in protection' on the board) as I've seen a number of folks complain that they've fried their tester.  My ATmega is socketed, but I don't have an endless supply of them.

I'm pretty sure that is the same thing as shorting out the capacitor. I'm not an expert, but I'm also pretty sure that is not good for the capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Distelzombie on April 13, 2018, 04:04:14 am
How is the pad on the board any more better than the metal arm of the contact-array thingy?
Title: $20 LCR ESR Transistor checker project
Post by: JonnieCache on April 13, 2018, 09:31:36 am
How is the pad on the board any more better than the metal arm of the contact-array thingy?

It’s not. It’s the same. It is meant for testing SMDs. When testing a capacitor, you should always make sure that it is discharged before testing it. Otherwise, you could damage the tester or yourself.

The proper way to discharge a capacitor is not by shorting out the two leads. By following the advice above (putting both leads on the same pad) you are doing just that. It’s no different than if you connected the leads together themselves or with a bit of wire. I would not follow the advice above for discharging. It is a hazard and can damage the capacitor.

If you do a search on the web about discharging a capacitor safely, you can find all sorts of solutions. Some are as simple as using a resistor to connect to the leads of the capacitor. While not great for all situations, at least that would not create a short. Make sure that the discharge circuit you are using will properly handle the amount of current and voltage that the capacitor may deliver.

The ideal solution is to purchase or build a simple device with proper current protection using a series of diodes and two LEDs. So, you will be able to see visually when the capacitor is discharged enough to be handled safely.

Something like this would do the job:

 http://www.instructables.com/id/Safe-Capacitor-Discharge-Tool/ (http://www.instructables.com/id/Safe-Capacitor-Discharge-Tool/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: misterno on April 13, 2018, 09:34:58 am
I 've post here because it looks like my own problem.

A good friend gave me a component tester with a 128X64 LCD screen like this one. The logo says: Mtester 2.07
(https://i.ebayimg.com/images/g/wfEAAOSw~3pacg4E/s-l1600.jpg)
The problem is that once i plug in the battery and press the button, the display shows the home screen and the message "... Starting"
After about 20 seconds, it shows the battery cell symbol and says "cell 53mV" by changing each time the button is pressed this 53mV in different values.
After I pulled out and measured all the semiconductors, resistors, capacitors etc and after I measured the voltage in the circuit and I found it 5V, I 've tried
to read the ATMEGA328P code but no luck.

I connect the cables to the SCK, MISO, MOSI, RST, GND, VCC to my TL866A programmer i have and try to read the program.
The developer read "successfully," as the program said, but did not show anything either in the code window or in the data.
Since nothing was done, I decided to clear the MCU and reprogram it. I load the HEX code I found and i was going to flash it.
I ended up with an error message and also i 've erased the signature ID of the chip (from 1E 95 0F to 00 00 00).

I change tactics and convert an arduino mega to ISP. I run the avrdude program with the appropriate parameters and control bits after I had
get backup of flash files, efuse, lock etc.
I tried the "erase" command but no luck. I also played with -F for testing.

The chip said it had been programmed, but the device did not understand anything, and continued to turn on the display and show the signal of the cell and the message "cell 53mV"

Is it any possibility to do a forcing flash to the chip?

Now I am in the process of ordering a new ATMEGA328P with a 8MHz clock as well as the original one.

Is it anything else i can try until its arrival?
TIA
Title: Re: $20 LCR ESR Transistor checker project
Post by: bugi on April 13, 2018, 10:32:21 am
The ideal solution is to purchase or build a simple device with proper current protection using a series of diodes and two LEDs. So, you will be able to see visually when the capacitor is discharged enough to be handled safely.
My quick and dirty slightly overkill capacitor discharger arrangement, using bunch of resistors, couple screw terminal thingies and two leads I happened to have available. Leads are long enough to keep that monster a safe distance away (no protections/case on it so for a short moment it could be dangerous to touch). I used to it to discharge PSU primary side caps, which is why so high resistance and power handling, but for lower voltages I just move the other lead to another point along the resistor chain. This is not for the most impatient person, but for me, it is better as it "forces" to give a little bit extra time to think what I'm about to do (or if I should do) next, while waiting the high voltages to drain down. Quick enough for me.

(EDIT: note, certainly not "CAT anything" on the "probing end", but tested in practice...)
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on April 13, 2018, 10:54:20 am
My quick and dirty slightly overkill capacitor discharger arrangement, using bunch of resistors, couple screw terminal thingies and two leads I happened to have available.

Wow! You get extra points for style! I love it! You are so right to take the extra time to think about it before you do it. I have to remind myself of that sometimes, too. Yours will certainly handle any necessary voltage! I still like to have the LEDs to make sure that it is adequately discharged, but that's just me. If you do the math (admittedly not hard) and have the right resistance (and time), you're good to go! VERY COOL!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 13, 2018, 10:55:12 am
The chip said it had been programmed, but the device did not understand anything, and continued to turn on the display and show the signal of the cell and the message "cell 53mV"

Some manufacturers set the lock bits and you have to erase the complete ATmega to be able to program a new firmware. The "cell" message is displayed when the tester detects a voltage at one of the probe pins. It can be caused by a fried MCU pin or some leakage current (PCB, ZIF socket, etc.).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 13, 2018, 11:18:30 am
My quick and dirty slightly overkill capacitor discharger arrangement, using bunch of resistors, couple screw terminal thingies and two leads I happened to have available.

I've simply taken a small plastic box with four 4mm banana jacks used for a voltage regulator before, connected inputs and outputs with a solid copper wire, soldered the next best power resistor (560 Ohms, 5 or 7W) across the red and black jacks and attached some old DMM probe leads. The "output" jacks can be used for monitoring the voltage with a DMM/VTVM. The only new part was the label I've printed ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: misterno on April 13, 2018, 11:28:11 am
The chip said it had been programmed, but the device did not understand anything, and continued to turn on the display and show the signal of the cell and the message "cell 53mV"

Some manufacturers set the lock bits and you have to erase the complete ATmega to be able to program a new firmware. The "cell" message is displayed when the tester detects a voltage at one of the probe pins. It can be caused by a fried MCU pin or some leakage current (PCB, ZIF socket, etc.).

That's i would to do i like to erase completely the chip but my programmers refuse to do it. Is there anyway to force erasing it? I will try to isolate the pins from the socket though to see if i keep on having the "cell" error.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 13, 2018, 11:49:25 am
I 've post here because it looks like my own problem.


Have the exact same tester and very similar problems to what you are experiencing. Turned out the main chip was damaged, so I changed it and got the tester to run perfectly again..it's been almost over a year, and it's still going strong.

In retrospect, I started thinking why was the main chip damaged, and I remember doing some in circuit ESR testing and at some point something felt weird when checking a capacitor and bang that was it, it was charged and damaged the Atmega328P of my unit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: misterno on April 13, 2018, 12:39:42 pm
I 've post here because it looks like my own problem.


Have the exact same tester and very similar problems to what you are experiencing. Turned out the main chip was damaged, so I changed it and got the tester to run perfectly again..it's been almost over a year, and it's still going strong.

In retrospect, I started thinking why was the main chip damaged, and I remember doing some in circuit ESR testing and at some point something felt weird when checking a capacitor and bang that was it, it was charged and damaged the Atmega328P of my unit.

You saved me from bad troubleshooting then. By the way i was wondering if its possible to simulate the 128X64 LCD used in this device as a VSM proteus project.
I looked for it into the web but no luck. It would be nice approach to this thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 14, 2018, 12:26:12 am


You saved me from bad troubleshooting then. By the way i was wondering if its possible to simulate the 128X64 LCD used in this device as a VSM proteus project.
I looked for it into the web but no luck. It would be nice approach to this thread.

Not too sure what you mean by VSM proteus project, but maybe someone else on the board may be able to answer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on April 14, 2018, 08:00:50 pm
So after a long flu induced hiatus with near death ER run in a speedy box with large hello world flashy LED's on top... and lots of prescription meds.... I'm starting to bounce back and play with stuff again.... I have to catch up on 20+ pages here too ;)

  Attached is a bit of extra motivation for me to follow through. These are my basic "out of the box" clone mods so far.
 Both the AY-AT and "little-t" have-
1.) Dual display mount configurations
2.) Fully broken out
       -ATmega328 pins for programming, testing and/or expansion
       -crystals
       -voltage reference
       -voltage regulator
       -ZIF socket
The Little t has-
  1.) variable cap for it's crystal
  2.) additional screw terminals for the extra pinouts not included with most kits.
The AY-AT has-
  1.) sense resistors broken out on pin headers with a set of the original 1% resistors, matched 5%, and 0.1% resistors from Mouser.
  2.) Rotary encoder broken out
LCR T3/T4 has-
  1.) Programming port broken out
  2.) Extra mounting hole/standoff w/5 standoffs added
  3.) Headphone Jack added for clip on test leads
  4.) Double Pole 4 terminal Calibration switch
  5.) Broken out ZIF socket
 
Also in the picture there are two 9 volt wall warts. One is configured with a 9 volt battery adaptor that includes a diode for reverse polarity protection, and a power indicator LED. The other adaptor is unmodified but is intended to be used with a capacitor multiplier circuit that is shown attached.
  So far the AY-AT's firmware as shipped sucks. The Little t has it's act together much better out of the box as does the T3/T4 although the latter does not have the menu setup or much else. It's basic but it works.
    I also built an entire breadboard version from KH's PDF and I had it working well. Unfortunately all that mess on a breadboard made it turn into a pumpkin at midnight after the first day of it working...so that one isn't going to be mentioned again ;)
-Jake
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on April 14, 2018, 10:58:02 pm
Hi Jake, I'm glad you are back and wish you all the best!!!
Looking forward to see your developments  :-+
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: joystik on April 16, 2018, 04:56:24 pm
IIRC, the Z180SN009 is based on the ST7735S. That controller supports up to 132x162 dots but the LCDs are 128x160 usually. A 128x160 LCD module could be wired starting at different addresses. Additionally the ST7735S has three pins for setting the LCD's resolution to either 132x162 or 128x160 which implies a specific wiring offset (moved to the mid). Maybe there are 128x160 modules wired starting at 1x1 but set to 132x162. When directions are flipped we'd get offset problems. So we need an option to shift x and y by the module specific offsets to cope with all the possible variations. And there's still the issue with the additional MCU controlling some important signals. Does anyone like to sponsor a TC-1 for reverse engineering and testing?

Did you get a hold of one of these?

If not, I could help. Send me a pm.
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on April 16, 2018, 05:39:20 pm
No, the STE2007 isn't supported. But based on the datasheet it shouldn't be hard to write a driver.

I am no programmer but can copy paste  :P

I am trying to make the driver, have downloaded the code and the closest match i found was for ST8814

here i tried to fiddle with the code but dont understand some of the variables

Code: [Select]
#elif (LCD_ST_TYPE == 2007) /* not ((LCD_ST_TYPE == 7565 || 1306 || 7108 || 7920 || 8812 || 8814) */
 // support for STE2007 , used for Nokia 1202
#undef SCREEN_WIDTH
#define SCREEN_WIDTH  96 /* for STE2007 */
    #undef SCREEN_HEIGHT
#define SCREEN_HEIGHT  68

//LCD-commands
#define CMD_SET_ADC_NORMAL      0xA0 //? Segment Driver direction select ?? 8.7 //
#define CMD_SET_ADC_REVERSE     0xA1 //?

#define CMD_SET_DISP_NORMAL     0xA6 /* Display normal / reverse, see 8.2 */
#define CMD_SET_DISP_REVERSE    0xA7 /* ** */

#define CMD_SET_BIAS_9          0xA2 //? Bias Ratio, see 8.17 //
#define CMD_SET_BIAS_7          0xA3 //? ? //

//? #define CMD_RMW                 0xE0
//? #define CMD_RMW_CLEAR           0xEE

#define CMD_INTERNAL_RESET      0xE2 /* Reset, see 8.14 */

#define CMD_SET_RESISTOR_RATIO  0x20 //? ? //

#define CMD_SET_VOLUME_FIRST    0x81 /* Electronic volume, see 8.12.3 */


//? #define CMD_SET_VOP_UPPER 0x20 /* upper 3 bits of Vop */ // The Set VOP instruction is used for programming the LCD drive voltage
//? #define CMD_SET_VOP_LOWER 0x80 /* lower 5 bits of Vop */ // not present in 2007

#define CMD_SET_ALLPTS_NORMAL   0xA4 /* Normal Display Mode see 8.3 */
#define CMD_SET_ALLPTS_ON       0xA5 /* Display all points ON/OFF, see 8.3 */

#define CMD_SET_POWER_CONTROL   0x2F /* Booster : ON, Voltage regulator : ON, Voltage follower : ON, see 8.11 */
#define CMD_SET_COM_NORMAL      0xC0 // ?
#define CMD_SET_COM_REVERSE     0xC8 // ?
#define CMD_DISPLAY_OFF         0xAE /* Display OFF see 8.1 */
#define CMD_DISPLAY_ON          0xAF /* Display ON see 8.1 */
#define CMD_SET_PAGE            0xB0 /* Page address set see 8.4 */
#define CMD_SET_START_LINE 0x40    /* Display start line address set 8.6 */
#define CMD_SET_COLUMN_UPPER    0x10 // ?
#define CMD_SET_COLUMN_LOWER    0x00 // ?
//Macros for LCD
#define lcd_write_data(data)                   _lcd_hw_write(0x01, data);
#define lcd_cursor_on()  // ignored
#define lcd_cursor_off() // ignored

need help with theses
Code: [Select]

//LCD-commands
#define CMD_SET_ADC_NORMAL      0xA0 //? Segment Driver direction select ?? 8.7 //
#define CMD_SET_ADC_REVERSE     0xA1 //?


#define CMD_SET_BIAS_9          0xA2 //? Bias Ratio, see 8.17 //
#define CMD_SET_BIAS_7          0xA3 //? ? //

//? #define CMD_RMW                 0xE0
//? #define CMD_RMW_CLEAR           0xEE


#define CMD_SET_RESISTOR_RATIO  0x20 //? ? //



//? #define CMD_SET_VOP_UPPER 0x20 /* upper 3 bits of Vop */ // The Set VOP instruction is used for programming the LCD drive voltage
//? #define CMD_SET_VOP_LOWER 0x80 /* lower 5 bits of Vop */ // not present in 2007


#define CMD_SET_COM_NORMAL      0xC0 // ?
#define CMD_SET_COM_REVERSE     0xC8 // ?

#define CMD_SET_COLUMN_UPPER    0x10 // ?
#define CMD_SET_COLUMN_LOWER    0x00 // ?


can someone help with the lines highlighted in bold, i tried to find them in datasheet but could get correct values for them
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 16, 2018, 06:31:17 pm
I bought 2 of the attached tester and installed the M version on one and the K version on the other. The one with the K version burnt the chip (v05 - diode array) and then the main chip. Should I be modifying it to use the K version? Also, with the M version, if there is nothing in the tester it gives me a reading of a capacitor of 15 pf, but seems to work ok otherwise.

A few users with the kit version of your tester had problems with the placement of the SRV05-4. When reversed the internal TVS diode will short Vcc to ground. Since it's an optional (weak) input protection the tester will also work without it. After programming the firmware please run the self-adjustment and the 15pF issue will vanish.

Hello Madires, I've tried running the self-adjustment and the 15pf issue did vanish. However, when I turn the tester off and on again, the 15pf is back? It doesn't seem to save the settings? Am i doing something wrong? Tks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 17, 2018, 10:02:16 am
Yep, the self-adjustment results need to be saved manually (menu item 'Save', choose profile #1). Please see the README file!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 17, 2018, 10:26:22 am
here i tried to fiddle with the code but dont understand some of the variables

Code: [Select]
//? #define CMD_RMW                 0xE0
//? #define CMD_RMW_CLEAR           0xEE

The STE2007 doesn't seem to have those commands.

need help with theses
Code: [Select]
//? #define CMD_SET_VOP_UPPER 0x20 /* upper 3 bits of Vop */ // The Set VOP instruction is used for programming the LCD drive voltage
//? #define CMD_SET_VOP_LOWER 0x80 /* lower 5 bits of Vop */ // not present in 2007

Based on the code for the ST8814
Code: [Select]
    lcd_command(CMD_SET_VOP_UPPER | ((volume >> 5) & 0x07));     // set upper Vop
    lcd_command(CMD_SET_VOP_LOWER | (volume & 0x1f));    // set lower Vop
it's obvious that the ST8814 has two commands to set an 8 bit contrast value, i.e. one for the upper 5 bits and another for the lower 3 bits. The STE2007 has the same commands.
Title: Re: $20 LCR ESR Transistor checker project
Post by: misterno on April 17, 2018, 04:58:13 pm
I finally found an ATMEGA328P and after a successful reflashing, i do manage to make it works!
Now i 'm thirsty for more experiments  ;). As i noticed when i push the button and then plug the battery,
i get a different menu with many options. I guess that maybe need a rotary encoder to work with it.
Is it possible to give me the link with schematic changes needed to make it fully working?
TIA
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 17, 2018, 06:35:15 pm
We've discussed rotary encoders and alternative push buttons just one page ago ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: misterno on April 17, 2018, 07:02:53 pm
We've discussed rotary encoders and alternative push buttons just one page ago ;)

Yes, after a better search i found it. Now i put the rotary encoder and the device is working like a charm!
Thank you all for help  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 17, 2018, 10:16:40 pm
Yep, the self-adjustment results need to be saved manually (menu item 'Save', choose profile #1). Please see the README file!

Thanks Madires, it worked! I really do like the M version of the software!
Title: Re: $20 LCR ESR Transistor checker project
Post by: misterno on April 18, 2018, 08:01:15 pm
We've discussed rotary encoders and alternative push buttons just one page ago ;)

Yes, after a better search i found it. Now i put the rotary encoder and the device is working like a charm!
Thank you all for help  :)

I did the encoder tweak and connect it to the right pins with 1K and 10K resistors as well.
Next i 've try to test the device better and i found that i have ver. 1.13K installed.
When i try to measure anything, i get the prompt like "the device is not calibrated"
I bridged the 3 probe wires together but the calibration message remains every time.
I also try to measure a couple of transistors, resistors, capacitors, diodes but the warning message appears every time.
What should i try next?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 18, 2018, 08:24:34 pm
The calibration procedure for the k-firmware is explained in Karl-Heinz' documentation (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf).
Title: Re: $20 LCR ESR Transistor checker project
Post by: misterno on April 19, 2018, 06:25:23 pm
As i try to calibrate the device, i did all the necessary steps to do it but no luck. I do have a working device with original Chinese firmware. Is it any possibility to read this original firmware came with device LCR T3 with 128X64 lcd display? I have a TL866A programmer.

I need to put both the .hex and the .eep file as well.
TIA
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on April 21, 2018, 01:07:34 am
As i try to calibrate the device, i did all the necessary steps to do it but no luck. I do have a working device with original Chinese firmware. Is it any possibility to read this original firmware came with device LCR T3 with 128X64 lcd display? I have a TL866A programmer.

I need to put both the .hex and the .eep file as well.
TIA
   There is a thorough walk through that describes how the calibration works in the PDF documentation for K Firmware. If you want help with this, what are your readings from all of the tests? I'm rather limited in what I can help with, but I know a bit about the project.
Title: Re: $20 LCR ESR Transistor checker project
Post by: misterno on April 22, 2018, 01:01:05 pm
It looks like i have a parasitic resistance or capacitance which interfere with the probes and not allowed me to calibrate the device. I will try to re-calibrate again with the zif socket soldered and cleaned.

EDIT: After a  good cleaning and flux removal i noticed with my microscope two small cracks to the track from TP1 and TP2. So i bridge them with a small wire and
now it's fully working.

Also i did the calibration as well  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: CheckOne Two on April 24, 2018, 07:08:32 pm
Hi all,

First a big thanks to all who have contributed towards the development of this very useful little tool ... the amount of documentation and posts is mind boggling!

I have purchased a 2578AY-AT clone kit (color screen with cd4050 buffer) and while putting it together have installed the advised 0.1% probe resistors, LM4040 (correct pin orientation) and MCP1702 ... the tester is up and running fine with firmware 1.12k.

As per the advised upgrades I have also purchased a 20Mhz crystal and some spare Atmega328-PU and would like to install the new crystal and try the latest 1.32m firmware. The plan was to leave the original 328 as is and flash the new firmware on one of the spare 328's then install that instead.

It is the programming of the firmware where I am falling flat on my face ... there are so many snippets of the procedure and many different ways to do it, I've been reading for days now but am still very confused and not confident in what I'm doing at all. It seems it should be very easy but I'm just lost in all the posts, documentation and different ways of doing it.

I use both Debian and Win10 here but have decided to try and do it in Win10 as it would seem to be more straight forward.

So far I have installed: AVRdude with all the required toolchain, GNU make and drivers etc. and am using the AVRDUDESS gui with it and have purchased a USBasp adapter and cable and installed the correct driver (this shows up in AVRdude).

First major problem was that the evaluation board that arrived with the USBasp adapter and cable is too large for the 328 (although it was meant to support it) ... then I opened the 328-PU's that I ordered from RS to find that they have sent me 328 U (not sure if this is a different chip but when I started looking for data on them I have found there are lots of different variants.

So a few questions because of my complete lack of experience in programming Atmega328's and Arduino etc. :

I am finding it really difficult to find a board to put on the end of my USBasp adapter cable that I am confident will support 328's ... can anyone point me to something suitable?

The kit arrived with a 328(P-PU) ... I ordered 328(-PU) as that was what was detailed in the upgrade list but on doing more research the P-PU has lower power consumption and was indeed cheaper than the -PU ... would I have been better off ordering P-PU's?

Can anybody point me to a complete simple guide to programming the AY-AT clone 1.32m firmware onto the 328 ... or anything else that follows the same procedure as the more I read and search now the more confused I get about it? The closest I got was a video on youtube but it was in russian  :-// and the files he was using looked nothing like the one's I have downloaded from Github. I'm taking it that the files he had are what is compiled by the Makefile but I'm really confused and stuck without a board to put the 328 on to try things out.

I'm not normally a person to ask for help but in this case I defo need pointed in the right direction ... I learn fast and any help will be well appreciated.

Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on April 24, 2018, 08:28:19 pm
First major problem was that the evaluation board that arrived with the USBasp adapter and cable is too large for the 328
I'm not sure I understand. Can you show a picture?
Title: Re: $20 LCR ESR Transistor checker project
Post by: CheckOne Two on April 24, 2018, 11:41:37 pm
I'm not sure I understand. Can you show a picture?

Thanks for the reply,

I bought the USBasp programmer, cable, 10pin to 6pin adapter and evaluation board as a "kit" and in the supported controllers in the ad the 328 was listed .... it turned out what they meant was the 328 was supported by the programmer, cable and adapter and the evaluation board was for Atmega16/32 so is far too wide for the 328.

https://www.ebay.co.uk/itm/AVR-ATMEGA16-Minimum-System-Board-ATmega32-USB-ISP-USBasp-Programmer-For-ATMEL/162949072121?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 (https://www.ebay.co.uk/itm/AVR-ATMEGA16-Minimum-System-Board-ATmega32-USB-ISP-USBasp-Programmer-For-ATMEL/162949072121?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649)

It's my fault for not knowing what to look for ... also I'm still not sure if I should have bought Atmega328P-PU controllers instead of ordering Atmega328-PU which have turned up marked Atmega328 U

Totally confused at the moment which is why I'm here asking advice before I waste any more money.

Is there a way I can still use the USBasp programmer and cable with some other board to program the other 328 to the new firmware so that buying them hasn't been a complete loss?

I've a feeling that if I can get the other 328 connected to AVRDUDE all the different little snippets of the programming procedure that I've read in the thread will start to make some sense.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on April 25, 2018, 12:08:08 am
Sorry I can't comprehend what you're saying. There's just too much. One thing at a time please, and in simple terms.

You're having trouble connecting a cable to a board?
A chip to a socket?

:-//
A photo of YOUR setup would really help here.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CheckOne Two on April 25, 2018, 01:05:39 am
Sorry I can't comprehend what you're saying. There's just too much. One thing at a time please, and in simple terms.

You're having trouble connecting a cable to a board?
A chip to a socket?

:-//
A photo of YOUR setup would really help here.

The link in my previous post is the exact programming kit I bought hoping to connect my spare Atmega328's to a computer to program with the latest 1.32m firmware ... there are clear pictures if you click on it.

No trouble connecting the cable to the USBasp programmer ... No trouble connecting the USBasp programmer to the computer ... all drivers are installed correctly and AVRDUDE is ready to go.

The problem is the Zif connector on the development/evaluation board is not compatible with Atmega328 and so I am asking what other cheap Atmega328 compatible board I could use with the USBasp programmer and cable.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on April 25, 2018, 01:26:35 am
OK Got it now. The socket is 21 pin but the 328 has 28 pins.

Just find the right board for the 328 on eBay. They're only a buck or two.

If you don't want to wait, maybe you chop the end off the zif socket that you already have to make it work. There's only 5 pins that you really need anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BroMarduk on April 25, 2018, 01:51:19 am
The problem is the Zif connector on the development/evaluation board is not compatible with Atmega328 and so I am asking what other cheap Atmega328 compatible board I could use with the USBasp programmer and cable.

Are you just stating that the ATMega328 is a 28 pin chip and the ZIF socket on the programmer is a 40 pin socket?  I'm not sure how the ZIF board is wired - so I wouldn't use it (40 pin ATMEGA16 has VCC on 10, but 28 pin ATMEGA328 has it on 7), but you can use the USB programmer piece and use jumper wires to a breadboard from the 10 pin connector on the other end.

See page 12 of the guide here:  http://www.hmangas.com/Electronica/Datasheets/USBasp/AVR-USBasp%20User%20Manual.pdf (http://www.hmangas.com/Electronica/Datasheets/USBasp/AVR-USBasp%20User%20Manual.pdf) for pin wiring.

I see the kit also comes with a 10-6 pin adapter so you could also use it and wire like here: http://www.chicoree.fr/w/images/b/b8/ATmega328P-ISP.png (http://www.chicoree.fr/w/images/b/b8/ATmega328P-ISP.png)

Title: Re: $20 LCR ESR Transistor checker project
Post by: CheckOne Two on April 25, 2018, 01:58:57 am
OK Got it now. The socket is 21 pin but the 328 has 28 pins.

Just find the right board for the 328 on eBay. They're only a buck or two.

If you don't want to wait, maybe you chop the end off the zif socket that you already have to make it work. There's only 5 pins that you really need anyway.

The dev board that I ordered by accident is actually 40 pin  :-[ but it's also far too wide for a 328 to fit it's pins into.

I'm having problems finding the right board ... that was why I was asking for advice on what would be compatible with my programmer and cable (which apparently do support Atmega328's) in case I buy something else that isn't suitable or there is a cheaper alternative and waste more money.

Most of the boards I see here in the UK seem to be arduino boards and I'm not sure if they are what I'm looking for ... also they seem to use a different usb cable.

Do I actually need a dev board with crystal etc. at the end of my USBasp programmer and cable to program the 328 or can I make something simple up myself to hold the 328 controller while programming?

Title: Re: $20 LCR ESR Transistor checker project
Post by: CheckOne Two on April 25, 2018, 02:05:16 am
The problem is the Zif connector on the development/evaluation board is not compatible with Atmega328 and so I am asking what other cheap Atmega328 compatible board I could use with the USBasp programmer and cable.

Are you just stating that the ATMega328 is a 28 pin chip and the ZIF socket on the programmer is a 40 pin socket?  I'm not sure how the ZIF board is wired - so I wouldn't use it (40 pin ATMEGA16 has VCC on 10, but 28 pin ATMEGA328 has it on 7), but you can use the USB programmer piece and use jumper wires to a breadboard from the 10 pin connector on the other end.

See page 12 of the guide here:  http://www.hmangas.com/Electronica/Datasheets/USBasp/AVR-USBasp%20User%20Manual.pdf (http://www.hmangas.com/Electronica/Datasheets/USBasp/AVR-USBasp%20User%20Manual.pdf) for pin wiring.

I see the kit also comes with a 10-6 pin adapter so you could also use it and wire like here: http://www.chicoree.fr/w/images/b/b8/ATmega328P-ISP.png (http://www.chicoree.fr/w/images/b/b8/ATmega328P-ISP.png)

Aha ... yes that is what I am saying, I ordered the wrong dev board by not paying attention to the whole listing. You have answered the question I was wondering about while I was writing it. So I can make my own 328 connector ?

Ok I'm off for a look at your links ... thanks  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: CheckOne Two on April 25, 2018, 02:42:23 am

See page 12 of the guide here:  http://www.hmangas.com/Electronica/Datasheets/USBasp/AVR-USBasp%20User%20Manual.pdf (http://www.hmangas.com/Electronica/Datasheets/USBasp/AVR-USBasp%20User%20Manual.pdf) for pin wiring.

I see the kit also comes with a 10-6 pin adapter so you could also use it and wire like here: http://www.chicoree.fr/w/images/b/b8/ATmega328P-ISP.png (http://www.chicoree.fr/w/images/b/b8/ATmega328P-ISP.png)

Wow ... is it really as easy as that and nothing more is required?  :)

Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on April 25, 2018, 03:48:01 am
The socket is 21 pin ... chop the end off the zif socket ... There's only 5 pins that you really need anyway.

Oops! The Mega16 is 44 pin. Forget the part about chopping.

In that case it should be fair easy to make the board you have to work. You might need to cut some traces and add bodge wires. Just make sure the chip gets 5V and ground on the proper pins, as well as the 4 SPI: MOSI, MISO, SCK, RST. (From datasheet)

Here ya go... only $1.70
https://www.ebay.com/itm/291550040876 (https://www.ebay.com/itm/291550040876)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on April 25, 2018, 06:03:02 am
ATmega8 ATmega48 ATMEGA88 Development Board AVR DIY Kit + USBASP AVR AC-PG-USBASP-UG-V2.0 (inside a box printed in 3D) programming one of my ATMEGA328P-PU for an AY-AT tester.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 25, 2018, 11:17:19 am
Hi, everybody! :D
I picked up a new firmware revision 790  from Karl-Heinz  for the device BsideESR02 and DTU-1701. In archive 2 firmwares with English language and a font 8x12 and 8x15, different in thickness. The bootpage for convenient use of a device is also a little edited.In the photo 2 different versions fonts of a firmware with Russian are only for evident comparing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BroMarduk on April 25, 2018, 05:56:52 pm
Wow ... is it really as easy as that and nothing more is required?  :)

That's how we did it in the "old" days with just a breadboard and jumper wires!

Full disclosure, I NOW have multiple ZIF sockets - which come in handy when programming chips in bulk.

Dan
Title: Re: $20 LCR ESR Transistor checker project
Post by: BroMarduk on April 25, 2018, 06:07:05 pm
BTW, if you find yourself programming the chips often, having the socket boards is great.   They have the power LED and reset buttons to make things easier.   Just keep in mind that most of the cheap prices are kits and by the time you build and test the kit, you could have run the jumpers to the breadboard multiple times :).
Title: Re: $20 LCR ESR Transistor checker project
Post by: CheckOne Two on April 26, 2018, 01:11:13 pm
Thanks for the help and suggestions all!

The dev board kits are too expensive here in the UK and I can't be bothered waiting for delivery from far east ...

So I think I'll just wire up a spare 28 pin Zif socket as per the wiring diagrams above and we'll see if I can get my head around programming the new firmware with AVRDUDE in win10  :)

If anybody has a link to a complete step by step tutorial that would be relevant for programming the transistor tester's firmware onto a 328 controller that would be of great help to me.

I know it's probably really easy ... I've just never done it before and would like to be sure the instructions I'm following are relevant for this application.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on April 26, 2018, 07:27:03 pm
Step 1 - download & extract the program package (posted on first page of this topic). Read the readme.

Step 2 - Find the directory containing the firmware appropriate for your flavour of clone and flash it to your 328.
(search eevblog forum for "transistor checker avrdude" for the commands)
Title: Re: $20 LCR ESR Transistor checker project
Post by: CheckOne Two on April 27, 2018, 05:23:29 am
Ok ... I've got it programming properly now  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 27, 2018, 03:05:20 pm
A quick update on the remote commands. After checking different ways to design a command interface the most suitable method is to simply follow the component output processing. Any other method would increase the RAM usage significantly. So far I've implemented a few basic commands like returning the firmware version for example. The interesting part is how to get the probing results. It's going to be a bunch of commands for retrieving specific information or values. After probing a component you'd issue a "COMP" to get the type of component (resistor, BJT, ...). Then another command to get the pinout or other details. So we will have a dedicated command for each information or value. This allows you to retrieve specific details without fetching everything. If you want to select or sort resistors you'd simply get the component type, and if it's a resistor then get the resistance value. It should be fairly simple to write a script or app for specific tasks. Please let me know if I missed anything or if you see any problems.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dathjeugjaqn on May 01, 2018, 04:50:47 am

Hi everybody! I am not an avr programmer but I have bought a multi function tester TC1 from china. but it does not work now. Show only white screen. Who has the TC1 firmware for me please file? thanks a lot!
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 01, 2018, 07:20:28 am
Who has the TC1 firmware for me please file?
Just look 3 posts behind yours.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on May 01, 2018, 01:11:41 pm
Any other method would increase the RAM usage significantly.

Which TT circuit are you using? Surely not one with the venerable 328 since utilisation
of its capacity is already basically at 100% and there is no TTL input pin either.  :palm:
I'd like to know in order to get ready for programming the command output. :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 01, 2018, 02:15:36 pm
I'm testing the bidirectional TTL serial interface and the remote commands on an ATmega644 dev board (similar to the 644 circuit in Karl-Heinz' documentation). I've posted the circuit diagram a while ago. A 328 might work too if you disable most additional features and use a I2C display to free up pins for the serial interface. After adding the remote commands I'll be able to give you a number.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dathjeugjaqn on May 03, 2018, 03:24:57 pm
IIRC, the Z180SN009 is based on the ST7735S. That controller supports up to 132x162 dots but the LCDs are 128x160 usually. A 128x160 LCD module could be wired starting at different addresses. Additionally the ST7735S has three pins for setting the LCD's resolution to either 132x162 or 128x160 which implies a specific wiring offset (moved to the mid). Maybe there are 128x160 modules wired starting at 1x1 but set to 132x162. When directions are flipped we'd get offset problems. So we need an option to shift x and y by the module specific offsets to cope with all the possible variations. And there's still the issue with the additional MCU controlling some important signals. Does anyone like to sponsor a TC-1 for reverse engineering and testing?

Can you give me the firmware of TC1?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 03, 2018, 04:14:59 pm
Sorry, I don't have a copy of the TC1's firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 05, 2018, 04:31:47 pm
I don't know why your tester reads larger caps a few percent low, but you could change the correction factor. Look for following lines in function LargeCap() in cap.c:
Code: [Select]
    if (Mode & PULL_10MS) Value /= 109;   /* -9% for large cap */
    else Value /= 104;                    /* -4% for mid-sized cap */

Large cap means capacitance > 47µF, and mid-sized cap 4.7 - 47µF. Simply lower the divisor to get a higher capacitance value.

Hi,madires!Whether there is an opportunity to make the same correction for capacitance lower than 4.7 µF?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 06, 2018, 10:25:23 am
Yes, that's going to be CAP_FACTOR_SMALL. I've already added CAP_FACTOR_MID and CAP_FACTOR_LARGE to set the correction factors for the other measurement ranges in case someone wants to adjust them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 10, 2018, 04:55:44 am
I have added a protection relay to my tester. It is essentially the same as described in the KHK manual.

I'm using Markus 1.32 firmware, and I have enabled "#define HW_DISCHARGE_RELAY" in config.h

But the relay does not energize when I test a component. I know my gizmo works, because if I manually apply 5V to PC4, I can hear the relay click.

Any ideas?
Title: Re: $20 LCR ESR Transistor checker project
Post by: shyney on May 10, 2018, 10:42:27 am
Hello everybody,

I'm a beginner in electronics and that's why I thought this tester is pretty handy for me.
I ordered one from AliExpress and since I own a 3D Printer I thought that I can print a case for it by searching for stl files on thingiverse.
Unfortunately I can't find any Stl files for my particular model. I would really appreciate if someone of you who already owns a stl file would share it with me.
This is the model I own:
https://imgur.com/a/7XLNXCI
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on May 10, 2018, 11:18:36 am
Hello everybody,

I'm a beginner in electronics and that's why I thought this tester is pretty handy for me.
I ordered one from AliExpress and since I own a 3D Printer I thought that I can print a case for it by searching for stl files on thingiverse.
Unfortunately I can't find any Stl files for my particular model. I would really appreciate if someone of you who already owns a stl file would share it with me.
This is the model I own:
https://imgur.com/a/7XLNXCI (https://imgur.com/a/7XLNXCI)

https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/50/ (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/50/)

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 10, 2018, 11:20:41 am
I have added a protection relay to my tester. It is essentially the same as described in the KHK manual.

I'm using Markus 1.32 firmware, and I have enabled "#define HW_DISCHARGE_RELAY" in config.h

But the relay does not energize when I test a component. I know my gizmo works, because if I manually apply 5V to PC4, I can hear the relay click.

Any ideas?

Does your tester have a rotary encoder?
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on May 10, 2018, 03:55:58 pm
I bought one of the 328 testers a few yrs. ago , haven't done any firmware upgrades , generally works well .
Question is , looking to build a new kit for several reasons , if I try to change firmware [ not proficient with programing etc. ] so not wanting to make my current unit unusable so the interest in finding a newer maybe better unit to build and update , also would like to get one that either comes with a case , or has one available - but I like the surface mount test-bed , so want it .
Maybe trying to have my cake & eat it too ;) , having plugin connectors for more versatile use , neither to eliminate the lockable holder .
I've search here & eBay for options , but get lost in the high volume of pages here & different descriptions on eBay .
Related , lots of forums subject get popular / lengthy and seem that they could benefit from some type of outline for those  that like me came early - and then came back late , or those that just came late ;) ?
Hopefully this helps ?
Thanks for all that have put lots of work into this .       
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 10, 2018, 07:03:30 pm
@madires

Yes, on PD1 & PD3.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 10, 2018, 08:57:07 pm
There's a known bug when using the discharge/protection relay and a rotary encoder. It's already fixed in the new version under development.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 10, 2018, 09:13:22 pm
 :-+ great.

It looks like you don't post code changes, only releases. And no bug tracker. Is this the case?
Title: Re: $20 LCR ESR Transistor checker project
Post by: joeyjoejoe on May 10, 2018, 11:24:29 pm
Picked one of these up, hoping to flash it to the latest version as well as replace it with some better resistors. Has anyone seen this variant?

https://i.imgur.com/uHB83T9.jpg
https://i.imgur.com/3lTwopT.jpg

Single sided board, 128x160 Color display.
https://i.imgur.com/q4h4DEn.png

Not sure if it's allowed to post a link to the seller, but the description was "Multi-purpose Transistor Tester 128*160 Diode Thyristor Capacitance Resistor Inductance MOSFET ESR LCR Meter TFT Color Display".

On bootup, it has a custom firmware by weiweitm and a link to their taobao site.

I soldered a header on, the AVR is locked of course, so I can't dump the firmware to just give it a shot. I browsed the subversion repo and google'd all the different display variants but didn't notice one that would be appropriate for this one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 10, 2018, 11:54:35 pm
In the "Markus" firmware, you can select your hardware options in config_328.h
Find out what chip drives the display, and enable that header in the code.
Compile from source.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 11, 2018, 10:01:53 am
It looks like you don't post code changes, only releases. And no bug tracker. Is this the case?

Yes and yes. But I document the bug fixes in the CHANGES file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 11, 2018, 10:12:12 am
Single sided board, 128x160 Color display.
https://i.imgur.com/q4h4DEn.png

I soldered a header on, the AVR is locked of course, so I can't dump the firmware to just give it a shot. I browsed the subversion repo and google'd all the different display variants but didn't notice one that would be appropriate for this one.

That tester seems to be a basic one with a ST7735 display. When the default pin assignment doesn't work check out the pin wiring and change the pin assignment accordingly. If you got it working please send me the configuration changes and I'll add them to the sample config for clones. I'd guess the OFF button is connected to PC6 (Reset). It could be possible that your tester has a power circuitry similar to the Fish8840 which has a design flaw draining the battery via the voltage divider for the battery monitoring when switched off. This is explained in Karl-Heinz' documentation, also including a simple fix.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 11, 2018, 05:01:27 pm
Single sided board, 128x160 Color display.
https://i.imgur.com/q4h4DEn.png
Hi, everybody! :)
At the Russian-speaking forum vrtp.ru we call this device as Fish8840TFT!
The participant of the forum bdk100 who owns such tester provided the schematic diagram(spl format) and the file of a configuration for madires firmware. I attach these files to the message.
This clone has some features which complicate compilation of own firmware.
1. Resolution of the display - 160х128, but the front frame superimposes a part of the image therefore it is necessary to move and offset the picture a little.
2. The LDO at 3.3V  from power which the display - very not reliable and ceases to work in case of connection of the programmator. Therefore it is recommended to disconnect or unsolder it before programming of the processor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: joeyjoejoe on May 11, 2018, 07:50:14 pm
Thanks! It looks like indman provided the configuration needed. Perhaps a mega328_fish8840_TFT directory could be made for this variant?

Could someone confirm my steps? First time flashing this.

1. I've downloaded https://github.com/svn2github/transistortester/blob/master/Software/Markus/ComponentTester-1.32m.tgz
2. Used the config_328.h that indman so nicely provided :)
3. Reviewed some of the config.h values, but only disabled a few things (PWM, signal gen)

Compiling it with avr_gcc, no errors, I have a hex file. Good to flash?
Title: Re: $20 LCR ESR Transistor checker project
Post by: HighMans on May 12, 2018, 12:12:14 am
Hello all! This is a really long thread, and I don't exactly know where to start, but I've three questions.

1. What would be the reason as to why my component tester is showing 15-18v as the battery voltage instead of the 9v's from the 9v battery? This (https://www.ebay.com/itm/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-New/232663900649) is the particular kit I bought, but I reckon it's all the same.

2. How do I go about upgrading this kit to the custom firmware that's around on the internet? I'm at version 1.12k currently.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 12, 2018, 01:36:29 am
1. What would be the reason as to why my component tester is showing 15-18v
Sounds like you mixed up some resistors. Double check the schematic.

2. How do I go about upgrading this kit to the custom firmware that's around on the internet? I'm at version 1.12k currently.
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg810893/#msg810893
You might try a search next time.

if I go to the selection menu and select selftest, it works fine. What've I done wrong?
I recommend you read the firmware Readme
Title: Re: $20 LCR ESR Transistor checker project
Post by: HighMans on May 12, 2018, 02:05:51 am
I looked at the resistors according to the assembly instructions provided to me and all of them do seem to be in place correctly.

Thanks for the link to the firmware, I tried clicking the search button on this forum thread but the results came up empty.

Finally, I figured out the selftest issue -- pebcak error as always. :P

Thanks again!
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 12, 2018, 02:46:54 am
What do you have on PC5?
Title: Re: $20 LCR ESR Transistor checker project
Post by: HighMans on May 12, 2018, 03:02:57 am
PC5? I don't see that on the silkscreen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 12, 2018, 03:30:56 am
pin 28 on the atmega
Title: Re: $20 LCR ESR Transistor checker project
Post by: HighMans on May 12, 2018, 04:10:20 am
Wow. Looks like I ripped out the connection for that pin on the IC Socket. I'm going to have to get a new one. Thanks for the help!
Title: Re: $20 LCR ESR Transistor checker project
Post by: JonnieCache on May 12, 2018, 01:30:10 pm
Wow. Looks like I ripped out the connection for that pin on the IC Socket. I'm going to have to get a new one. Thanks for the help!

I’ve done that before. They come out sometimes, but you can put it right back in. When you solder it, it will work just fine!
Title: Re: $20 LCR ESR Transistor checker project
Post by: HighMans on May 12, 2018, 02:55:35 pm
That'd be fine if it wasn't for the fact that it's long gone now! I "fixed" it by cleaning out the solder, and sticking in a solid wire to make a connection -- works well enough :P
Title: Re: $20 LCR ESR Transistor checker project
Post by: joeyjoejoe on May 12, 2018, 03:46:05 pm
2. The LDO at 3.3V  from power which the display - very not reliable and ceases to work in case of connection of the programmator. Therefore it is recommended to disconnect or unsolder it before programming of the processor.

Totally fried this thing :)

I removed it, and now I can program (haven't yet), but the display is also working?! If the 3v3 is supplying power, with that removed, I'm not sure how this is possible based on that schematic....
Title: Re: $20 LCR ESR Transistor checker project
Post by: joeyjoejoe on May 12, 2018, 05:09:13 pm
To set the proper offset for FISH8840_TFT, find in ST7735.c:

Code: [Select]
#ifdef LCD_ROTATE
  /* swap X and Y */
  #define LCD_PIXELS_X        LCD_DOTS_Y
  #define LCD_PIXELS_Y        LCD_DOTS_X
  #ifdef LCD_OFFSET_X
    #define LCD_SHIFT_Y       3     /* shift y by 4 dots */
  #endif
  #ifdef LCD_OFFSET_Y
    #define LCD_SHIFT_X       1     /* shift x by 2 dots */
  #endif
#else
Title: Re: $20 LCR ESR Transistor checker project
Post by: Argiros on May 13, 2018, 07:18:28 am
Well I finally did it. I follow the schematic and found the PD1 and PD3 pins from the CPU which in my case goes to R21 and R22  10K resistors (SMD 103) and they connect to A0 and SDA LCD pins respectively, for my Display ST7735 although in Karl's doc it says RS and SI for ST7565. So one can solder BEFORE the resistors or else it wont work. I pulled out the selection button and place in his place the rotary and it works perfectly! Better than the other which came with his build in rotary encoder. The only catch is that it powers on with the other reset button and when I put in power it opens automatically. Maybe I miss something from the other side of the circuit in the selection button. Now it is a usefull device, and I dont know why they designed it with only two buttons reset and select, when there are menus , choices etc. Now I can play with the software to make it work as I want, for ex the display I want it rotated in landscape and not portrait. Thank you madires and all the other friends who helped me.

<Argiros>
Can I add a rottary switch button to this model GM328B ? Where I can solder this ?

or else can I add 3 more buttons for using them for scrolling up down and for back ?
<madires>
You can use two push buttons for up/down (increase/decrease) instead of a rotary encoder (k-firmware: WITH_ROTARY_SWITCH 4, m-firmware: HW_INCDEC_KEYS, and check the portpins). The test button is mandatory, either as a separate push button or integrated in the rotary encoder. And there's no back button. As timelessbeing already has mentioned, the wiring is explained in Karl-Heinz' documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 14, 2018, 03:34:18 am
I'm trying to put the Karl-Heinz firmware on my "M328" tester

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=187603;image)

I tried the firmware from all these folders which seemed relevant:
mega328_GM328
mega328_st7565
mega328_st7565_kit

But the display turned out upside down and backwards each time. Also the rotary encoder didn't work. So I guess I'll have compile from source.

Does anybody know where these options are configured? The KH code is much more difficult to follow, than MR's.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on May 14, 2018, 10:10:15 am
I have the same variant. The mega328_st7565_kit folder is the correct one.
I didn't try the latest build, but you shouldn't need to modify anything, it should just works.

If not try different combinations of the following settings in the Makefile
CFLAGS += -DLCD_ST7565_H_FLIP=0
CFLAGS += -DLCD_ST7565_V_FLIP=1

Mauro

Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on May 14, 2018, 08:40:48 pm
I just tried the latest 791 build.
The files inside the mega328_st7565_kit folder works fine without any change on my tester (same as your picture).
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 14, 2018, 09:48:18 pm
You're right. I must have gotten some files mixed up, but it works now. Thanks for confirming.

Do you know how to enable the protection relay in the firmware? I didn't find anything in the documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2018, 10:42:49 am
You don't need to enable anything in the k-firmware for using the protection relay. It's part of the basic code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on May 15, 2018, 05:04:32 pm
I have added a protection relay to my tester. It is essentially the same as described in the KHK manual.



Can you place some pictures here?
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on May 16, 2018, 04:45:38 am
Here is a picture of my 10 pounds of sh.. in a 5-pound bag: Relay protection, Rotary encoder, Li-Ion battery, USB charger, Step Up converter, High voltage converter for Zener testing, Banana sockets and a new 16Mhz crystal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 16, 2018, 07:01:38 am
You don't need to enable anything in the k-firmware for using the protection relay. It's part of the basic code.
hmm... at which exact moment is PC4 supposed to go high?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 16, 2018, 09:57:23 am
The protection relay is basically controlled by ADC_DDR. When the output mode is enabled (setting the bit for TPRELAY) the relay is released, and when set to input mode (clearing the bit) the relay is activated. To figure out when the relay will be activated/released please see main.c for all occurrences of ADC_DDR. >:D
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on May 16, 2018, 01:09:30 pm
Still looking for another one of these - recommendation / link .
I have one from several yrs. ago ,
Would like to get one that has a case , or case ready , I do surface mount work - so wold like the pads on the outside of case to test SMD
Any suggestions / links ?
Ebay has too many , with possibility of getting one that is " not " recommended ?
Thanks   
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on May 16, 2018, 02:37:14 pm
Hello, greetings to all.

I have this checked in disuse and wanted if it is possible to update it.
It has mounted the ATMEGA168v, in the firm K it appears but there are 3 versions and I do not know what would be necessary.
I would appreciate your help to know what is the version needed to update the device.

(http://s2.subirimagenes.com/otros/previo/thump_9850349recort2.jpg)

Thank you very much

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 16, 2018, 04:13:46 pm
I'd recommend to upgrade the MCU to an ATmega 328. The 168 has only 16kB flash and can run just the very basic features.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on May 16, 2018, 04:38:36 pm
I'd recommend to upgrade the MCU to an ATmega 328. The 168 has only 16kB flash and can run just the very basic features.

Okay, thank you very much
Title: Re: $20 LCR ESR Transistor checker project
Post by: -AFS- on May 18, 2018, 06:01:02 pm
I'm sorry for asking such a noob question, but I haven't find any information about this.

I have one of these modules, with the ST7735 display.
(http://ceezblog.info/images/blog/avr-ttester-kit2.jpg)

I am trying to update the firmware, but when I compile the code, I get that the program goes up to 113.2% of the memory of the device.
What am I doing wrong?

The only way I have found to significantly decrease the size of that is compilling without menu, but that makes no sense, as it must be possible to use it...

Sorry if the question is very stupid or if it has already been answered.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sofakng on May 18, 2018, 06:16:15 pm
Still looking for another one of these - recommendation / link .
I have one from several yrs. ago ,
Would like to get one that has a case , or case ready , I do surface mount work - so wold like the pads on the outside of case to test SMD
Any suggestions / links ?
Ebay has too many , with possibility of getting one that is " not " recommended ?
Thanks
I'm also looking for a recommendation.  I'd like something that has a removable Atmega328 chip so I can upgrade the firmware (?).

The Drok Mega328 (https://www.amazon.com/Transistor-Capacitor-DROK-Capacitance-Automatic/dp/B01MS1FOYM/ref=sr_1_1?ie=UTF8&qid=1526667328&sr=8-1&keywords=Drok+Mosfet+Transistor+Capacitor+Tester%2C+DROK+Mega328+NPN%2FPNP+Transistor+Diode+Resistor+Inductor+Capacitance+MOS+SCR+ESR+Meter+Automatic+Checker+Detector+with+1.8%22+12864+TFT+Color+LCD+Digital+Display) on Amazon looks nice (if a bit expensive, but it has a very nice case), but I don't know if I can be updated, etc.

Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 18, 2018, 07:06:44 pm
@ -AFS-

Is your toolchain updated? Some versions of GCC are known to produce fatter code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on May 18, 2018, 08:06:11 pm
Still looking for another one of these - recommendation / link .
I have one from several yrs. ago ,
Would like to get one that has a case , or case ready , I do surface mount work - so wold like the pads on the outside of case to test SMD
Any suggestions / links ?
Ebay has too many , with possibility of getting one that is " not " recommended ?
Thanks
I'm also looking for a recommendation.  I'd like something that has a removable Atmega328 chip so I can upgrade the firmware (?).

The Drok Mega328 (https://www.amazon.com/Transistor-Capacitor-DROK-Capacitance-Automatic/dp/B01MS1FOYM/ref=sr_1_1?ie=UTF8&qid=1526667328&sr=8-1&keywords=Drok+Mosfet+Transistor+Capacitor+Tester%2C+DROK+Mega328+NPN%2FPNP+Transistor+Diode+Resistor+Inductor+Capacitance+MOS+SCR+ESR+Meter+Automatic+Checker+Detector+with+1.8%22+12864+TFT+Color+LCD+Digital+Display) on Amazon looks nice (if a bit expensive, but it has a very nice case), but I don't know if I can be updated, etc.

On the price , seems ok , it is assembled & in a case , so extra , color display .
On the minus no SMD to test surface mount testing / identifying lose components , missing rotary encoder - so missing some options - but I do not know what .   
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on May 18, 2018, 08:19:58 pm
@ -AFS-
Is part of the growing pains. I had the same problem a while back. It took me a while to get it to compile with the right versions of the software. With the right versions of the compiler you should not have space problems just as mentioned by timelessbeing.

I had some notes but I don't know if they would help. (I don't have the links but they should be easy to find)
*Collection of Helpful information *
Firmware Building environment for Windows

1.   Download and Install WinAVR > Link
2.   Download Toolchain > Link
3.   Extract Toolchain using Winrar or 7-zip into the C:\WinAVR-20100110 folder overwrite everything, avr, bin, doc...
4.   credit: tom
Compiling the Firmware

1.   Download GNU tarball > Link
2.   Extract GNU tarball using Winrar or 7-zip somewhere
3.   Download and Install Cygwin 64 bit
4.   Launch Programmers Notepad installed by WinAVR
5.   Open desired Makefile in the device specific folder from extracted tarball
6.   Click Tools menu > [WinAVR] Make All
7.   In the folder of Makefile you will find the flash .hex and eeprom .eep files
.   From heelzFlyW
.   I have mega328_color_kit "AY-AT" with LCD 7735.  Took trendy 1.24m for a drive.

To get LCD to work I had to change lines below.  One weird thing I see is on Start the LCD refreshes with multi color dots/sand.

In config_328.h:
1. From
.   Code: [Select]
.   #define LCD_ST7735
.   #define LCD_DC           PD3            /* port pin used for D/CX */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SDA          PD1            /* port pin used for SDA */
...
To
.   Code: [Select]
.   #define LCD_DC           PD1            /* port pin used for D/CX */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SDA          PD3            /* port pin used for SDA */
2. From
.   Code: [Select]
.   //#define LCD_FLIP_X                      /* enable horizontal flip */
#define LCD_FLIP_Y                      /* enable vertical flip */
.   To
.   Code: [Select]
.   #define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y                      /* enable vertical flip */
And for Encoder changed:

3. From
.   Code: [Select]
.   #define ENCODER_A        PD2       /* rotary encoder A signal */
.   To
.   Code: [Select]
.   #define ENCODER_A        PD1       /* rotary encoder A signal */


I also noticed in PWM and Square Wave modes it shows Pins 2-13.  I don't understand what it means   

In variables.h
.   Code: [Select]
.   const unsigned char PWM_Probes_str[] EEMEM = "2-13"

DIY Kit "AY-AT"
- with ST7735 color LCD module
- provided by flywheelz@EEVBlog


Hardware Options:

#define HW_ENCODER
#define HW_REF25
#define HW_ZENER
#define HW_FREQ_COUNTER


LCD module:

#define LCD_ST7735
#define LCD_COLOR                       /* color graphic display */
#define LCD_SPI_BITBANG                 /* bit-bang SPI interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RES          PD0            /* port pin used for /RESX */
#define LCD_CS           PD5            /* port pin used for /CSX (optional) */
#define LCD_DC           PD1            /* port pin used for D/CX */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SDA          PD3            /* port pin used for SDA */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       160            /* number of vertical dots */
#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_ROTATE                      /* switch X and Y (rotate by 90°) */
#define FONT_10X16_H                    /* 10x16 font, horizontally aligned */
#define SYMBOLS_24X24_H                 /* 24x24 symbols, horizontally aligned */


Rotary Encoder:

#define ENCODER_A        PD1       /* rotary encoder A signal */
#define ENCODER_B        PD3       /* rotary encoder B signal */


Input for the frequency counter is PD4 (T0).

 :-//


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 19, 2018, 10:54:21 am
To get LCD to work I had to change lines below.  One weird thing I see is on Start the LCD refreshes with multi color dots/sand.

-> LCD_LATE_ON  (starting with v1.28m)

I also noticed in PWM and Square Wave modes it shows Pins 2-13.  I don't understand what it means   

It meant signal output via probe #2 and ground via probes #1 and #3. Was changed to "1:- 2:s 3:-" later on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 19, 2018, 09:45:08 pm
Would someone with a TC-1 running the vendor's modified firmware please do me a favor and check two signals with a scope? The TC-1 has an 8-pin MCU (U4) which controls the power. Pin 7 is connected to PD1 of the ATmega324, and pin 8 to PD2. A short press of the start button will power on the tester and pin 7 goes high while pin 8 stays low. Does any of those pins change their state when pressing the button briefly again (most likely pin 7)? Do pin 7 or 8 receive any signals from the ATmega?
Title: Re: $20 LCR ESR Transistor checker project
Post by: -AFS- on May 19, 2018, 10:43:30 pm
@ -AFS-

Is your toolchain updated? Some versions of GCC are known to produce fatter code.

@ -AFS-
Is part of the growing pains. I had the same problem a while back. It took me a while to get it to compile with the right versions of the software. With the right versions of the compiler you should not have space problems just as mentioned by timelessbeing.

I had some notes but I don't know if they would help. (I don't have the links but they should be easy to find)
*Collection of Helpful information *
Firmware Building environment for Windows
[...]

Thank you very much timelessbeing and casinada for your advise.

I tried updating the toolchain, and now it compiles fine. To the limit (99.1% Full), but ok.
I have already uploaded it, and seems to be working, so I suppose I did the rest of the proces correctly.

I'm not sure if I updated the toolchain to the last version. But it is working, so no problem for now. XD

Thankyou
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 20, 2018, 01:40:06 am
I'm not sure if I updated the toolchain to the last version.

Current Versions (https://github.com/osx-cross/homebrew-avr#current-versions)

    gcc 7.2.0 & 6.4.0
    binutils 2.29.0
    avr-libc 2.0.0
    gdb 7.8.2

Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 20, 2018, 03:51:27 am
You don't need to enable anything in the k-firmware for using the protection relay. It's part of the basic code.

Well I had absolutely no luck with this.

To be sure, I removed my relay from the tester, and instead I connected an LED and DMM (set to peak hold) to PC4. I tested some components and PC4 never went high. I started the tester with probes shorted, and PC4 never went high. (1.13k)

I also ran a quick sketch to flash an LED on PC4, just to make sure the mcu wasn't damaged.

 :-//

Both the voltage ref and resistor to Vcc on PC4 are removed, if that makes any difference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 20, 2018, 10:31:48 am
The protection relay needs the pull-up resistor since PC4 is simply set to low to switch the relay. It's designed this way to support an external voltage reference and the protection relay via the same pin.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 20, 2018, 11:23:18 am
To set the proper offset for FISH8840_TFT, find in ST7735.c:

Code: [Select]
#ifdef LCD_ROTATE
  /* swap X and Y */
  #define LCD_PIXELS_X        LCD_DOTS_Y
  #define LCD_PIXELS_Y        LCD_DOTS_X
  #ifdef LCD_OFFSET_X
    #define LCD_SHIFT_Y       3     /* shift y by 4 dots */
  #endif
  #ifdef LCD_OFFSET_Y
    #define LCD_SHIFT_X       1     /* shift x by 2 dots */
  #endif
#else

The next firmware version will allow you to set the offsets for the ST7735 directly in config-<mcu>.h. For example:
#define LCD_OFFSET_X     2
#define LCD_OFFSET_Y     1

There are also some ST7735 displays with the addressing aligned to the mid.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on May 20, 2018, 01:05:24 pm
Would someone with a TC-1 running the vendor's modified firmware please do me a favor and check two signals with a scope? The TC-1 has an 8-pin MCU (U4) which controls the power. Pin 7 is connected to PD1 of the ATmega324, and pin 8 to PD2. A short press of the start button will power on the tester and pin 7 goes high while pin 8 stays low. Does any of those pins change their state when pressing the button briefly again (most likely pin 7)? Do pin 7 or 8 receive any signals from the ATmega?

Hi Madires. There does appear to be data between this U4 and the atmega. see attached pics. (U4-pin7,8.jpg)  pin 7 ch1 and 8 ch2 at turn on and approx 1 sec later data appears at pin 7 only, (U4-pin7.jpg).
Pin 3 also go high at turn on. Pressing the button while on doesn't show any activity on Pins 7,8.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 20, 2018, 03:05:47 pm
Thanks for checking the two pins! Someone has put some effort into preventing others to use his clone with the original OSHW firmware. So far we know that U4 is an STC15L104W MCU. That MCU stays in sleep mode until the start button is pressed. Then it sets pin 3 high to enable the boost converter IC. Pins 7 and 8 are obviously TX and RX for a serial protocol. When the start button is pressed for 1.5s the MCU disables the boost converter. The same after a timeout (there are two pads on the PCB for setting a delay of 10-25s) triggered by the end of a measurement/test cycle (this is suggested by the manual). We don't know if a button press is passed on to the ATmega. Let's discuss our options:
- don't buy the TC-1 clone
- reverse engineer the protocol
- write a new firmware for U4 (simple power_on signal from the ATmega and button press signal for the ATmega)
- replacing U4 with some transistors (standard power circuitry)
- let the ATmega create an enable signal for the boost converter in parallel with U4 (via diodes?) and add a test button (plus rotary encoder?)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 20, 2018, 10:57:26 pm
The protection relay needs the pull-up resistor since PC4 is simply set to low to switch the relay.

Huh?
Wouldn't a pullup resistor turn the transistor/relay on?

The documentation says, "The de-energized contacts of the relay protect the ATmega". It seems to me that grounding PC4 would de-energize the relay and short the probes. This is the opposite of what I thought .... I don't get it. :o

http://tinyurl.com/y8uwzne6 (http://tinyurl.com/y8uwzne6)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 21, 2018, 11:03:24 am
The relay contacts are wired to short the tests pins when the relay isn't powered. When powered the shorts are removed. This way the relay can be switched by changing the MCU pin between input and output mode (low). For the external reference we need the input mode (HiZ) to feed the ADC. The pull-up resistor also turns on the relay via the BJT (removes shorts). In output mode the current (limited by the pull-up resistor) flows to ground via the MCU and the BJT switches off the relay (shorts test pins). And with this design you won't BBQ the ATmega when you connect a charged cap to a switched-off tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on May 21, 2018, 01:54:06 pm
Is there a tester that implements all those new features?

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 4RESTER on May 21, 2018, 02:33:53 pm
Thanks for the firmware of the BSIDE ESR02 PRO (DTU-1701)!
Is there an even newer firmware (with russian or english)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 21, 2018, 02:48:41 pm
4RESTER,these firmwares which I offered are relevant and fresh today! :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: 4RESTER on May 21, 2018, 02:51:50 pm
Available also here: https://www.banggood.com/BSIDE-ESR02PRO-Digital-Transistor-SMD-Components-Tester-Diode-Triode-Capacitance-Inductance-Meter-p-1218985.html (https://www.banggood.com/BSIDE-ESR02PRO-Digital-Transistor-SMD-Components-Tester-Diode-Triode-Capacitance-Inductance-Meter-p-1218985.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 21, 2018, 03:35:39 pm
Is there a tester that implements all those new features?

There's no clone with all hardware options available at the moment. DIY time! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on May 21, 2018, 03:55:47 pm
The relay contacts are wired to short the tests pins when the relay isn't powered. When powered the shorts are removed. This way the relay can be switched by changing the MCU pin between input and output mode (low). For the external reference we need the input mode (HiZ) to feed the ADC. The pull-up resistor also turns on the relay via the BJT (removes shorts). In output mode the current (limited by the pull-up resistor) flows to ground via the MCU and the BJT switches off the relay (shorts test pins). And with this design you won't BBQ the ATmega when you connect a charged cap to a switched-off tester.

Hi, originally the base of switching transistor was simply pulled up to the +5V, so once the 5V was on the relay got energized.  That is how my relay protection is still working.  Why was it changed to control the switching transistor with PC4, what was wrong with the original concept?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 21, 2018, 05:10:54 pm
I can't recall that the protection relay was controlled differently in the past (I've checked an old schematic from 2013). But I can add an option to control the relay the way you've described (dedicated pin for the relay). Are the test pins shorted when the relay is energized or when it's not energized? The fail safe solution would be the latter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 22, 2018, 12:40:46 am
The relay contacts are wired to short the tests pins when the relay isn't powered...

Got it. Thank you for clarifying.

Hopefully, the probes are shorted when the tester is switched on, but not in the process of measuring.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on May 22, 2018, 02:54:38 am
I can't recall that the protection relay was controlled differently in the past (I've checked an old schematic from 2013). But I can add an option to control the relay the way you've described (dedicated pin for the relay). Are the test pins shorted when the relay is energized or when it's not energized? The fail safe solution would be the latter.
I guess you are right, I looked at my (older) copy of Karl's manual and the transistor controlling the relay IS driven by PC4.  I cannot remember that I ever changed Karl's original circuit, I just remember that when I built my tester about 3 years ago I simply had the base of the switching transistor pulled directly to the +5V.  When the relay is not energized (no 5V)  the relays contacts (normally closed) shorts the test leads and when you activated the tester, 5V is available and that turns on the switching transistor and the relay opens the shorted test leads. 

When I read your explanation how the protection relay works I simply remembered that my protection relay wasn't driven by PC4 but  my circuit operated exactly as you described.  I guess Karl's circuit was never changed, I simply just activated the relay differently with the same final results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 22, 2018, 05:17:48 am
While we're talking about relays ...

The most sensitive small dip relay that I could find ... will draw 30mA at 5v.   Most other small relays I found, drew more than twice that.
The "must operate" current of my 5V Omron is 20mA. 30mA is actually over spec for it.

you might want to consider connecting the collector to Ubat instead of Vcc as it is possible that the relay load would pull Vcc down during the measurement and significantly impact the measurement accuracy.
Would this be an issue for 250mA MCP1702 regulator with 10uF of output capacitance?  A coil has inductance, so it shouldn't draw huge current spike.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 22, 2018, 10:22:41 am
I'm using (I think Karl-Heinz too) the 4.5V type from the Fujitsu FTR-B3 series (current 30ish mA). No problems powering it also by the 5V LDO. The boost converter for the Zener check is more demanding and the firmware takes this into account by delaying measurements after pressing the test button. But I'd recommend to power the boost converter by a second LDO. And if you do that you can also use the second LDO for the protection relay.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 22, 2018, 05:38:24 pm
you have to make sure that the voltage at the connection of both resistors (PC4) is not around 2.5V to prevent the tester from thinking it's an external 2.5V reference (k-firmware).

What is the voltage range that it looks for?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 22, 2018, 06:16:59 pm
The range is 2250-2750mV for both firmwares (k & m).
Title: Re: $20 LCR ESR Transistor checker project
Post by: joeyjoejoe on May 22, 2018, 11:25:49 pm
Is there a tester that implements all those new features?

There's no clone with all hardware options available at the moment. DIY time! ;)

I might design a PCB and share it, to be populated by higher quality components.

Any thoughts on the "best" design? AY-AT looks decent with TVS diodes, rotary encoder.

https://github.com/Upcycle-Electronics/AVR-Transistor-Tester/blob/master/AY-AT%20J1.3.pdf
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 23, 2018, 12:47:32 am
the relay can be switched by changing the MCU pin between input and output mode (low).

So in light of this, I had to redesign my protection circuit.

I used a simulator first.
With voltage reference: http://tinyurl.com/y9hw5smz (http://tinyurl.com/y9hw5smz)
Without voltage reference: http://tinyurl.com/ycedlh6g (http://tinyurl.com/ycedlh6g)

It turns out you don't even need a resistor on the transistor base. All you need is the pullup (without a v. ref that is)

Then I assembled it on a breadboard and hooked it up to the tester, and tried the two firmwares.

Karl (1.13k)
Worked fine. Just be aware of this: The tester only seems to be protected when turned off. For me, the relay energizes as soon as the tester is powered up, and stays on until you shut it off. That means that that if you are testing components in continuous mode (in other words, one after another without powering off in between), you are vulnerable to BBQing the mcu. Then the relay is essentially pointless.

Markus (1.32m)
Worked great. Also, the tester *only* unprotects the probes during actual measurements. When a measurement is complete, the relay releases and doesn't energize again until you press the button for a new measurement. When you're navigating menus and such, the tester is also protected. This is much nicer in my opinion.  :-+

My only wish is that this feature was documented better.  ;)

There's a known bug when using the discharge/protection relay and a rotary encoder. It's already fixed in the new version under development.
This doesn't seem to be an issue for me.


On to the zener extension ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on May 23, 2018, 05:16:11 pm
It turns out you don't even need a resistor on the transistor base. All you need is the pullup (without a v. ref that is)
To turn on a BJT all you need is to provide enough base current times the transistor current gain to support the collector current.  So of course all you need is one resistor to limit the base current and that resistor can be a simple pull-up, and like I mentioned earlier, I simply have the pull-up resistor going directly to the +5V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 23, 2018, 06:00:39 pm
Thanks. I know how a transistor works. I said "it turns out ..." because I didn't know how the mcu was controlling the relay. Neither did you, it seems.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on May 23, 2018, 06:20:45 pm
So why were you surprised that "It turns out you don't even need a resistor on the transistor base. All you need is the pullup".  Of course you don't need a base resistor if you have a pull-up resistor to ANY positive voltage when the tester becomes active providing enough base current!  You don't need a silly circuit simulation to figure this out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 23, 2018, 07:01:50 pm
Maybe you don't need it, but electronics is just a small pastime of mine.  I find that visualizing a circuit helps me a great deal to wrap my head around how it works. And if it were simply a matter of one transistor, I certainly wouldn't need it, but there are other things going on. You have to watch the voltages and currents on the PC4 pin, the relay etc.  This topic is frequented by beginners, so I posted my findings in case it helps somebody else.

I wouldn't say I was surprised about the reisistor. I just remember madires saying ...
What is the procedure if not using the voltage reference, but relay extension is used? No pull-up resistor?

A pull-up resistor at PC4 (ATmega 328) and the BJT's base resistor should be replaced by a higher value.
... so I was following up about that.

It's too bad this upsets you so much, but hopefully calling it silly made you feel better about yourself.  :clap:
Title: Re: $20 LCR ESR Transistor checker project
Post by: bugi on May 23, 2018, 08:14:13 pm
While perhaps not quite the same issue as to this particular transistor base resistor case, but, this reminded me of another, old case, where sometimes seemingly "silly" things can after all be required. Beginners (or even somewhat more experienced persons) might not immediately realize it. Testing in practice is then the only way to make sure / to find out. Or asking someone else for opinion/facts.

As an example, an old MCU project. I had put small series resistors on all main "bus" digital I/O pins, connected to another MCU about 10cm away directly (no pull-ups or anything). I.e. 5V AVRs talking to each other, easy stuff. Even usual simulations would not have revealed why I did so... and seemingly they are totally useless resistors, right?  The person converting the schematics to a PCB and assembling the units thought so, too, and decided to leave the resistors out.

The end result was that the MCUs couldn't talk with each other properly. After plenty of poking around, the other person looked at the schematic again, glued the resistors (or were they array chips, don't remember), hand-tweaked the circuits on PCB etc.  And the MCUs finally talked.

In that particular case, those "totally useless resistors" were to handle heavy noise levels... crude, but worked wonders.

(No, it wasn't really any smart idea on my part; I just had read about such possibility and solution some time before, and decided to put them in, just in case, thinking the resistors aren't that expensive, considering that all the other parts were already going over 30€ or something.)

(EDIT: sorry, so off-topic... nothing about LCR meter...)
Title: Re: $20 LCR ESR Transistor checker project
Post by: lordstein on May 24, 2018, 02:46:27 am
today i was updating my transistor tester, change the 4mm conector to allow use the multimeter probes, and wiring and installing a conector for icsp program, i use the tl866a to program my transtor tester, this is the diagram.
(https://preview.ibb.co/jAj4BT/20180518_160709a.jpg) (https://ibb.co/etOaJ8)

this is the wiring

(https://preview.ibb.co/bzxud8/20180523_171835a.jpg) (https://ibb.co/iRUkko)

programing
(https://preview.ibb.co/iXzqJ8/20180523_173716a.jpg) (https://ibb.co/dOLKBT)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 24, 2018, 05:55:19 pm
Someone has asked how much flash memory the remote command option will need. It's nearly finished and uses a little bit less than 3kB flash and about 250 Bytes EEPROM (just the remote commands without the TTL serial driver).
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on May 24, 2018, 06:41:08 pm
I guess multiple post are needed for some questions , they get missing in all the firm-ware posts ;)
Still looking for suggestions on the most up to date kit to buy ?
I have one from a few yrs. ago , I seem to run into lots issue with updates etc. , not a programer etc.
So thought that finding a 2nd one , my 1st had some pads for surface mount components and a rotary switch [ I get the impression that allow for more ??? ] .
Also would like to find one that may have a box to put in , and still have the SMD pads etc.
I've some searches and do not seem to come up with answers - that are not almost like reading from page one .
I gotten replies from others trying to do the same --- no responses ?
Maybe this thread should be called the firmware only thread , no hardware replies ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 24, 2018, 06:55:00 pm
Usually you'll find the answer on the last 10 pages. Same question over and over again ;) And the same answer: AY-AT
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 24, 2018, 07:32:22 pm
I guess multiple post are needed for some questions
I guess some people would rather keep tapping you on the shoulder, rather than to do a bit of reading ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on May 24, 2018, 07:58:09 pm

192 pages , is not a bit of reading .

I also did some reading , searching , but most of the last couple of yrs. is about firmware .

So if its easier to be an --- than help never mind , hopefully that the internet is not getting that bad ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 25, 2018, 08:12:14 am
 :blah:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 25, 2018, 07:24:03 pm
Get your programmer ready! ;)

v1.33m 2018-05
- Fixed orientation of TRIAC symbol in symbols_32x32_hf.h.
- Added remote commands for automation (via TTL serial).
- The x & y offsets for the ST7735 driver can be changed now.
- Entering the menu by a short circuit of the probes is an option now
  (UI_SHORT_CIRCUIT_MENU).
- Fixed problem with discharge relay when using rotary encoder.
- Added configuration switch to disable MCU sleep modes.
- Added RX support to TTL serial driver (bit-bang & hardware USART).
- Fixed error in serial text output and added serial output for results of
  the optocoupler check.
- Danish texts (provided by glenndk@mikrocontroller.net)
- Settings for capacitor correction factors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 25, 2018, 09:01:13 pm
Great work! Can't wait to try this out.

This has interesting potential for further development. I envision adding a bluetooth module to the tester, and using a smartphone app with GUI to control it.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 26, 2018, 10:07:09 am
Get your programmer ready! ;)
v1.33m 2018-05
madires added still something... :D
- The configuration setup for the Fish8840TFT clone is added to the Clones file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on May 27, 2018, 03:26:47 pm
I don't know why your tester reads larger caps a few percent low, but you could change the correction factor. Look for following lines in function LargeCap() in cap.c:
Code: [Select]
    if (Mode & PULL_10MS) Value /= 109;   /* -9% for large cap */
    else Value /= 104;                    /* -4% for mid-sized cap */

Large cap means capacitance > 47µF, and mid-sized cap 4.7 - 47µF. Simply lower the divisor to get a higher capacitance value.

Get your programmer ready! ;)

v1.33m 2018-05
- Fixed orientation of TRIAC symbol in symbols_32x32_hf.h.
- Added remote commands for automation (via TTL serial).
- The x & y offsets for the ST7735 driver can be changed now.
- Entering the menu by a short circuit of the probes is an option now
  (UI_SHORT_CIRCUIT_MENU).
- Fixed problem with discharge relay when using rotary encoder.
- Added configuration switch to disable MCU sleep modes.
- Added RX support to TTL serial driver (bit-bang & hardware USART).
- Fixed error in serial text output and added serial output for results of
  the optocoupler check.
- Danish texts (provided by glenndk@mikrocontroller.net)
- Settings for capacitor correction factors.


For me correct values were
Code: [Select]
    if (Mode & PULL_10MS) Value /= 102;   /* -9% for large cap */
    else Value /= 99;                    /* -4% for mid-sized cap */

Where the settings are in 1.33m firmware?


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 27, 2018, 04:01:22 pm
The correction factors are set in config.h:
Code: [Select]
/*
 *  Correction factors for capacitors (in 0.1%)
 *  - positive factor increases capacitance value
 *    negative factor decreases capacitance value
 *  - CAP_FACTOR_SMALL for caps < 4.7µF
 *  - CAP_FACTOR_MID for caps 4.7 - 47µF
 *  - CAP_FACTOR_LARGE for caps > 47µF
 */

#define CAP_FACTOR_SMALL      0      /* no correction */
#define CAP_FACTOR_MID        -40    /* -4.0% */
#define CAP_FACTOR_LARGE      -90    /* -9.0% */
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on May 28, 2018, 01:45:30 pm
Hi.
Madires
I'm looking for information to put the protection relay for your ComponentTester-1.33m firmware. And made the one that I have in other testers but it does not work ..
I pray information and a scheme to be able to do it.

Thank you very much
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 28, 2018, 03:35:41 pm
Have you enabled HW_DISCHARGE_RELAY in config.h?
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on May 28, 2018, 05:25:52 pm
Have you enabled HW_DISCHARGE_RELAY in config.h?

Thank you very much.
a greeting
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 28, 2018, 08:06:32 pm
I pray information and a scheme to be able to do it.
There is a schematic in the manual.
https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on May 29, 2018, 06:01:53 pm
(http://s2.subirimagenes.com/otros/previo/thump_9850349recort2.jpg)

The Atmega168 has already been changed to the 328, in addition to a 20MHz crystal.

What Software do I have to put? Mount an LCD SCM1602c 2x16

Thank you very much
Title: Re: $20 LCR ESR Transistor checker project
Post by: slinkygn on May 29, 2018, 11:40:17 pm
If you get an AY-AT Clone, the following is a list of hardware corrections to order if you would like to optimize it's operation on M-Firmware. If you normally order parts from Mouser or Digikey all information and links are provided. (No Supplier Affiliation/No...

<clip>

(3×)470k Resistors
TE Connectivity
MPN: H8470KBZA
Metal Film Resistors - Through Hole H8 470K 0.1% 100PPM
MoPN: 279-H8470KBZA (http://www.mouser.com/Search/ProductDetail.aspx?R=H8470KBZAvirtualkey50680000virtualkey279-H8470KBZA)
$0.97each (8/2017)
$2.91 (×3)
DkPN: PTF475KCCT-ND (https://www.digikey.com/product-detail/en/te-connectivity-passive-product/H8470KBZA/H8470KBZA-ND/2373532) (not stocked)
Dk Alt:
475k 0.1% 1/8W
Vishay Dale
MPN: PTF56475K00BYEB
DkPN: PTF475KCCT-ND (https://www.digikey.com/product-detail/en/vishay-dale/PTF56475K00BYEB/PTF475KCCT-ND/2273757)
$1.64each (8/2017)

(3×)680ohm Resistors
TE Connectivity
MPN: H8680RBYA
Metal Film Resistors - Through Hole H8 680R 0.1% 15PPM
MoPN: 279-H8680RBYA (http://www.mouser.com/Search/ProductDetail.aspx?R=H8680RBYAvirtualkey50680000virtualkey279-H8680RBYA)
$1.14each (8/2017)
$3.42 (×3)
DkPN: H8680RBYA-ND (https://www.digikey.com/product-detail/en/te-connectivity-passive-product/H8680RBYA/H8680RBYA-ND/2373526)(not stocked)
Dk Alt:
681ohm 0.1% 1/4W
Note: listed as discontinued by digikey (w/available stock 8/2017)
TT Electronics/Welwyn
MPN: RC55Y-681RBI
DkPN: 985-1036-1-ND (https://www.digikey.com/product-detail/en/tt-electronics-welwyn/RC55Y-681RBI/985-1036-1-ND/2401900)
$1.70each (8/2017)

<clip>

Apologies if this has been asked.  I can't imagine it hasn't been brought up yet, but at the same time seaching turned up nothing -- which may just mean I'm terrible at coming up with the right search terms!

The parts recommendations here give alternates for each of the 0.1% resistors.  The suggested alternate for the 470k resistor is a 475k 0.1%, and the one for the 680ohm resistor is 681 0.1%.

Thing about that is, 475k is of course slightly over 1% more than 470k, and 681 is much closer but still between 0.1% and 0.2% of 680.

I can't imagine the recommendations are "wrong" and just uncaught after this long, but the only other conclusion I could come to would be that the 0.1% resistor tolerance is at least an order of magnitude above what the device's precision could resolve anyway.  If a 475k 0.1% resistor is for all practical purposes equivalent to a 470k 0.1% resistor, doesn't that indicate that one would likely still be just fine using a 470k 1% resistor?  (And in fact, perhaps even more so than using a 475k 0.1% resistor, as if the calculations depend fairly tightly on the 470k value then probability is on your side that you're better being +-1% off than starting at +1.1% and then being +-0.1% off from there.)

And same question for the 681 vs the 680 ohm resistor -- except doubly so, since the 680ohm value poses a problem in the 0.1% tolerance in that it doesn't exist in the E192 value series, or in fact any series higher than E24, and 681 of course doesn't exist in E24 or prior but is in every precision higher (including E192) so it's possible but far more difficult to find a 680ohm 0.1% cap than a 681ohm 0.1% cap, but at 1% it's actually slightly easier around here to find 680ohm than 681ohm caps (and it's a huge pain to find 5% 681s of course, not that it matters for our purposes).
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 30, 2018, 01:03:59 am
I think the idea is that the exact value of the resistor is not super important. The software can compensate for the actual value. Most important is that the resistor is stable, and doesn't drift. I could be wrong though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2018, 10:29:25 am
The Atmega168 has already been changed to the 328, in addition to a 20MHz crystal.

What Software do I have to put? Mount an LCD SCM1602c 2x16

k-firmware: mega328_2X16_menu (but needs to be re-compiled for 20MHz)
m-firmware: choose HD44780 driver
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2018, 10:48:55 am
I can't imagine the recommendations are "wrong" and just uncaught after this long, but the only other conclusion I could come to would be that the 0.1% resistor tolerance is at least an order of magnitude above what the device's precision could resolve anyway.  If a 475k 0.1% resistor is for all practical purposes equivalent to a 470k 0.1% resistor, doesn't that indicate that one would likely still be just fine using a 470k 1% resistor?  (And in fact, perhaps even more so than using a 475k 0.1% resistor, as if the calculations depend fairly tightly on the 470k value then probability is on your side that you're better being +-1% off than starting at +1.1% and then being +-0.1% off from there.)

The values of the probe/test resistors R_low and R_high can be changed in a config file for the source code. If you go for different values please update the config file. Very simple, isn't it? ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2018, 10:52:07 am
I think the idea is that the exact value of the resistor is not super important. The software can compensate for the actual value. Most important is that the resistor is stable, and doesn't drift. I could be wrong though.

You're spot on!
Title: Re: $20 LCR ESR Transistor checker project
Post by: slinkygn on May 30, 2018, 04:54:51 pm
The values of the probe/test resistors R_low and R_high can be changed in a config file for the source code. If you go for different values please update the config file. Very simple, isn't it? ;)

Ah hah!  I knew my search talents were at fault.  Just in a different way. :)  One of the first places I looked was the Karl-Heinz document, thinking "surely there might be a config setting for those values," but R_low and R_high are not mentioned as config settings there.  And then for some reason I didn't think to search for related config changes in the thread, and only looked for info specifically about resistor precision -- my apologies!

The question that I remain curious about then would be: at what point does the device's inherent precision make it so there isn't further return to increasing the precision of the test resistors?

To explain my question in a different way:  when I first thought about there possibly being a config value for the resistor values, I figured I could simply sit with a pile of a few hundred 5% resistors for each value (which I happen to have sitting around) and, with a nice Fluke 6.5-digit bench multimeter that is available for my use near here, a spreadsheet and a few minutes of patience, I could easily find three resistors that were within 0.1% value of each other.  Now I'm curious about extending that concept -- I erred toward caution early in the decision process here and bought 0.1% resistors anyway, and bought 10 because there was a significant price break at that quantity (can't have too many resistors!).  Well, now I suppose I could use that same nice bench meter and measure out those 10, and I imagine the likelihood of my finding three that are within, say, 0.05% of each other is actually rather high.  Maybe even 0.02% or so.  And I could always buy more resistors... that same pile of a few hundred resistors as before but all 0.1%, plus said patience, would make 0.01% precision between the three resistors easily achievable -- and maybe even more than that.  (And I don't think the compiler particularly cares if there are a few more significant digits in the value of course: if I find, say, 3 caps that are all within 0.01% of 473188 ohms  or 688.888 ohms or whatever I'd think r_high and r_low will handle those numbers just fine!)  I imagine it's largely a thought-experiment kind of question, then, but how precise can these values get before they are *too* precise to make a difference?
Title: Re: $20 LCR ESR Transistor checker project
Post by: slinkygn on May 30, 2018, 05:15:45 pm
I think the idea is that the exact value of the resistor is not super important. The software can compensate for the actual value. Most important is that the resistor is stable, and doesn't drift. I could be wrong though.

Is this actually the case?  I think it's Vishay that did some white papers on the drift stability of modern metal-film resistors.  If I recall, drift in most precision resistors one would be likely to buy today is really remarkably low.  I do have some military-spec 6-band resistors around here somewhere that have ppm/degC drift bands and failure-rate markings on them, but largely speaking a parts tester would have to be in some pretty unusual temperatures to really see a difference that would even come close to approaching 0.1% of the resistor's value.  (Consider: 0.1% = 1000ppm; just as an example, the datasheet for the 470k 0.1%'s I just bought -- cheapest I could find -- state that they're 50ppm/degC, so a 10degC/18degF difference in temperature would make the resistor deviate 0.05%, and may still be within its rated value.)  Further, all the test resistors would ostensibly be experiencing the same temperature change, so would be all drifting in the same direction; for all practical purposes real-world drift performance as far as deviation between resistors goes would likely be an order of magnitude greater.

Likewise, age-related drift at typical operating temperatures is very low as well -- for those same resistors I bought, they're rated at <0.1% drift over 8000h of continuous operation at 85degC.  Since that is a very temperature-dependent value, and these resistors are unlikely to ever see even half of that temperature, their drift over the lifetime of the device is virtually negligible.

(I should note that the drift characteristics of these 0.1% resistors are virtually identical to much more easily acquirable 1% resistors, as they are both metal film resistors.)

So I think it may be that the precision of the resistors both among themselves and with relation to the set config values are the criteria of importance, more so than drift of the resistor (which is not related to being 0.1% or 5% precision but instead separately specified as a ppm/degC value for temperature-based drift, and failure rate ppm for drift in general).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2018, 05:54:03 pm
I imagine it's largely a thought-experiment kind of question, then, but how precise can these values get before they are *too* precise to make a difference?

I'd guess 0.01%. Instead of buying 0.1% resistors you could also use a proper bench DMM to measure and select 1% metal film resistors. They don't have to be exactly 680 or 470k as you can change the values in the config file. We recommend the 0.1% types because they are much cheaper than a 6-1/2 digit or better DMM ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on May 30, 2018, 06:51:56 pm
The values of the probe/test resistors R_low and R_high can be changed in a config file for the source code.
Does the calibration/self test not adjust for the resistors too?

I imagine it's largely a thought-experiment kind of question, then, but how precise can these values get before they are *too* precise to make a difference?
I like having some margin too. I would rather my accuracy be limited by things like the PCB, not my choice of resistors. Besides, most kits come with 0.1% resistors any way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2018, 07:40:18 pm
The values of the probe/test resistors R_low and R_high can be changed in a config file for the source code.
Does the calibration/self test not adjust for the resistors too?

No, but for the probe leads / PCB traces and the ATmega's internal switching. Therefore probe resistors with known value are required.
Title: Re: $20 LCR ESR Transistor checker project
Post by: slinkygn on May 30, 2018, 11:19:01 pm

I'd guess 0.01%. Instead of buying 0.1% resistors you could also use a proper bench DMM to measure and select 1% metal film resistors. They don't have to be exactly 680 or 470k as you can change the values in the config file. We recommend the 0.1% types because they are much cheaper than a 6-1/2 digit or better DMM ;)

But it's such a good investment! ...
Who am I kidding, the one I have access to isn't even mine.  If I could afford that, I probably wouldn't need to be building meters out of $20 DIY kits, would I? :)

One more quick question on this topic (which worst case I can answer myself by actually grabbing the code, I suppose): I mentioned that I didn't see r_low and r_high in Karl-Heinz' documentation.  Does that mean that the config values are only in the m-version, and not the k-version?  Will I have to go ifdef-hunting in the code if I want the k-version to use different cap values?
Title: Re: $20 LCR ESR Transistor checker project
Post by: phunky2018 on May 31, 2018, 10:05:42 am
Hi folks,
this is my first post, I have some trouble with 1.33m firmware and sending serial commands to the tester.

My hardware:
- China AY-AT tester (16MHz)with a broken TFT Display (this was the reason why i want to activate and test the automation via serial tx and rx via e.g. terminal program)
- FTDI USB-Serial adapter (5V)

My own changes so far:
1. I removed the (broken)TFT, wired PD0 to FTDI TX pin and PD1 to FTDI RX pin and of course GND together
2. Cut the trace between R13 and PD1, wired now one of the encoder pins to PD2 and the other encoder pin is default PD3
3. Enabled UI_SERIAL_COPY, UI_SERIAL_COMMANDS, SERIAL_HARDWARE and SERIAL_RW (config.h)
4. Changed the ENCODER A pin to PD2 (config_328.h)

Receiving data from the tester to the terminal program is working, but if I send OFF or PROBE or MSG or something else, the tester goes to a closed loop(it's look like the tester reboot endless) and I don't get a messages back on the terminal screen (e.g. OK or ERR).
After a restart, the receiving data from the tester is working again till I send something to the tester.

Any ideas or are more modifications necessary?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 31, 2018, 10:42:35 am
One more quick question on this topic (which worst case I can answer myself by actually grabbing the code, I suppose): I mentioned that I didn't see r_low and r_high in Karl-Heinz' documentation.  Does that mean that the config values are only in the m-version, and not the k-version?  Will I have to go ifdef-hunting in the code if I want the k-version to use different cap values?

For the k-firmware it's R_L_VAL and R_H_VAL.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 31, 2018, 11:08:48 am
Receiving data from the tester to the terminal program is working, but if I send OFF or PROBE or MSG or something else, the tester goes to a closed loop(it's look like the tester reboot endless) and I don't get a messages back on the terminal screen (e.g. OK or ERR).
After a restart, the receiving data from the tester is working again till I send something to the tester.

Any ideas or are more modifications necessary?

Are PD0 and PD1 also used for the LCD? In most cases LCD_RESET and LCD_CS are optional and can be disabled. Simply change the other control lines to unused pins. It seems we need a dummy LCD driver with no functionality or maybe ANSI/VT100 output.
Title: Re: $20 LCR ESR Transistor checker project
Post by: phunky2018 on May 31, 2018, 05:14:32 pm
I disabled LCD_RES and LCD_CS in config_328.h without success.

/*
 *  ST7735, SPI interface (bit-bang, 4 wire)
 */

//#if 0
#define LCD_ST7735
#define LCD_COLOR                       /* color graphic display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
//#define LCD_RES          PD1            /* port pin used for /RESX (optional) */
//#define LCD_CS           PD5            /* port pin used for /CSX (optional) */
#define LCD_DC           PD3            /* port pin used for D/CX */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SDA          PD4            /* port pin used for SDA */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       160            /* number of vertical dots */
//#define LCD_FLIP_X                      /* enable horizontal flip */
#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_ROTATE                      /* switch X and Y (rotate by 90°) */
//#define LCD_OFFSET_X     4               /* enable x offset of 2 or 4 dots */
//#define LCD_OFFSET_Y     2               /* enable y offset of 1 or 2 dots */
//#define LCD_LATE_ON                     /* turn on LCD after clearing it */
#define FONT_10X16_HF                   /* 10x16 font, horizontally aligned & flipped */
//#define FONT_8X16_CYRILLIC_HF           /* 8x16 cyrillic font, horizontally aligned & flipped */
//#define SYMBOLS_30X32_HF                /* 30x32 symbols, horizontally aligned & flipped */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SDA        /* port pin used for MOSI */
//#endif

Maybe your idea in the future with an dummy LCD could work. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 31, 2018, 06:11:37 pm
Hi madires! :)
At me it is also impossible to receive the response in an automatic mode.
ERR responds to any command.
I try simulation of the project in Proteus.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on May 31, 2018, 06:47:55 pm
Nice! I started making the same yesterday! Can you share the Proteus project files?

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 31, 2018, 07:06:37 pm
So far the project in Proteus crude! I am not ready will share. Perhaps later. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 31, 2018, 07:52:52 pm
I disabled LCD_RES and LCD_CS in config_328.h without success.

Could you please try SERIAL_BITBANG?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 31, 2018, 08:00:21 pm
Hi madires! :)
At me it is also impossible to receive the response in an automatic mode.
ERR responds to any command.
I try simulation of the project in Proteus.

At least you get some feedback. ;) Which control characters is the virtual terminal sending as newline?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tongbajiel on June 01, 2018, 12:30:20 am
Hello guys.
"SALAM" form Indonesia.

Let me share my job testing for last version ESR from Karl-Heinz trunk on proteus 8.7 sp2
with ST7735 lcd.

This project based from old trunk KH esr files for ST7565 from this post.
You can find the original works here.
http://kazus.ru/forums/showthread.php?t=8259&page=20# (http://kazus.ru/forums/showthread.php?t=8259&page=20#)

Schematic is very simple and not full like real board.
REMEMBER !!! its made just for test only on proteus.

you can change whatever you want for simulation, but must be warning if execution on real HW.

I change some parameter on makefile and not connected all of lcd pin on proteus to make its displayed and works on proteus.
I change "MAX_MENU_LINES" from 5 to 14 menu in "function_menu.c" in this test.
Remember to change the parameter if you want to flash in real hardware before compile it.
uncomment #CFLAGS += -DUSE_EEPROM in makefile if compile for real HW.

If anyone has same project from Markus based esr, and works displayed on proteus with BW/Color lcd, please share it, because still now i got not working simulation for Markus based esr.


Finally.... I hope you like, and forgive for my bad English.

Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on June 01, 2018, 03:43:52 pm
Hello, thanks to all of you and I was able to modify and update my old meter in disuse.  :clap:

Changed the ATmega168 by a 328, and incorporated a 20MHz crystal.

I have put the firmware K "mega328_2X16_menu" compiled at 20MHz, since firmware M has been impossible to make it work.

When I want to measure any component it does not recognize any and it gives practically the same results for all of them and not differentiating between them.

The only thing that recognizes well are the capacitors, but it gives a very high ESR.

In the calibration in the step that asks to put a capacitor of 4-30nf when putting it it remains indefinitely stopped, it is necessary to remove the condenser so that it goes ahead and finish the calibration.

Attached some photos, have if you can help me solve the problem.

Thank you

(http://s2.subirimagenes.com/otros/previo/thump_985272020180601123344.jpg)     (http://s2.subirimagenes.com/otros/previo/thump_985272120180601123428.jpg)

(http://[http://s2.subirimagenes.com/otros/previo/thump_985272220180601123612.jpg/img]     [img]http://s2.subirimagenes.com/otros/previo/thump_985272320180601123709.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on June 01, 2018, 03:55:20 pm
(http://s2.subirimagenes.com/otros/previo/thump_985272320180601123709.jpg)     (http://s2.subirimagenes.com/otros/previo/thump_985272520180601123801.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: lordstein on June 01, 2018, 06:23:28 pm
i was measuring ESR on a visually damaged capacitor (680mF and 25v) and  i was very impressed because the values were very close to those shown by the atlas esr70. version 1.13k
(https://preview.ibb.co/bOkHHd/20180523_185450.jpg) (https://ibb.co/bF2KVy)

(https://preview.ibb.co/eFpNiJ/20180523_185617.jpg) (https://ibb.co/gfhxHd)
delete tripit account (https://deleteacc.com/tripit)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 01, 2018, 07:19:40 pm
At least you get some feedback. ;) Which control characters is the virtual terminal sending as newline?
The virtual terminal supports the CR (0x0D) codes (carriage return), BS (0x08) (return) and BEL (0x07) (a sound signal) controlling ASCII. All other codes, including line feed of LF (0x0A), are ignored.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 01, 2018, 07:50:57 pm
The remote commands expect each line to be terminated with either <CR><LF> or <LF> (CR=0D, LF=0A). Oops, found a typo in the README (it should be <LF> and not <NL>).
Title: Re: $20 LCR ESR Transistor checker project
Post by: tongbajiel on June 01, 2018, 08:06:29 pm

At me it is also impossible to receive the response in an automatic mode.
ERR responds to any command.
I try simulation of the project in Proteus.

Hi indman, Can you share the proteus source please
Title: Re: $20 LCR ESR Transistor checker project
Post by: phunky2018 on June 02, 2018, 06:01:59 am
Hi madires,
yes SERIAL_BITBANG is working, in my case at PD4 and PD5.
Now i can play with all commands.
Thank you.

One stupid question, everytime I reprogram the chip, is also necessary to reprogram again the fuses?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 02, 2018, 11:09:51 am
Interesting! So I'll have to recheck SERIAL_HARDWARE on the ATmega328. The fuses need to be set just the first time (new or salvaged ATmega).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 02, 2018, 11:21:28 am
Quick update on the m-firmware. I'm working on an 1Wire driver (probes or a dedicated MCU pin are possible) and support for the DS18B20 temperature sensor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: goophoba on June 03, 2018, 05:18:44 am
I think I am going in circles and I was hoping someone might know whats up.

Got a "M328" (same as timelessbeings at Reply 4744 pg. 190) and I updated to version 1.33m on a spare 328 pulled out of a UNO (perhaps relevant?). I followed directions from  this post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893) using the eep and hex from  mega328_st7565_kit (https://github.com/svn2github/transistortester/tree/40d63e456e41a257a49c97259f3ec870869f5cef/Software/trunk/mega328_st7565_kit) on gitub. Got a "end of file error" and no write. Files also larger than others some others I've found.

I then tried the latest K-H M328 1.12 hex and eep from avrtester.tode (http://www.avrtester.tode.cz/index.php?p=firmware) and no joy. Flash and eeprom seem to erase and write just fine, no warnings in cmd aside from "cannot set sck period" but thats never got in the way before.  Even with the seemingly ok write when the mega328p is returned to "M328" tester the screen just stays blank when turned on. No power LED either. (contrast issue?) Led light and screen backlight stay on without any image.

As a last shot tried the files from here (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/). Hex file 1k bigger at 87.4k than the previous hex attempted. These files worked, but the firmware comes up as V1.13k in the tester even though the page downloaded from says 1.33m. Seems like I am grabbing the wrong files but they are all labeled "mega328_st7565_kit".

Am I using the newest at 1.13K?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on June 03, 2018, 07:45:24 am
/Software/trunk directory is 'k' firmware.
/Software/Markus directory is 'm' firmware. (hex/eep files not provided. You need to compile)
Title: Re: $20 LCR ESR Transistor checker project
Post by: goophoba on June 04, 2018, 01:00:33 am
ah, got it. Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on June 04, 2018, 07:56:00 pm
(http://s2.subirimagenes.com/otros/previo/thump_985272320180601123709.jpg)     (http://s2.subirimagenes.com/otros/previo/thump_985272520180601123801.jpg)

The problem that had to mediate all components was due to this resistance was not welded in place.
I do not know if it came from home or moved when the ATmega168 was changed by the Atmega 328.

Thank you very much to all.
regards

(http://s2.subirimagenes.com/otros/previo/thump_9853136copia-2-de-201806041.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 07, 2018, 06:54:15 pm
Another quick update. The idea of a VT100 display driver appealed to me so much that I've simply written one. ;) It supports color (option switch) and replaces a LCD display completely, i.e. same output but no symbols, and special characters are replaced by standard ones. And it works also for all menus and tools. The benefits are freed-up MCU pins for other hardware options and a smaller firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 12, 2018, 08:14:52 pm
We have a simple modification for the TC-1 clone to make it work with the k/m-firmware. The control MCU U4 is replaced by a small circuit with two transistors. The best way seems to be to use thin enamel wire and hot glue. The ATmega's PD1 is the input for the test button and PD2 the output for the power control. Any jelly bean small signal NPN and PNP are fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eliocor on June 12, 2018, 09:24:30 pm
Quote
We have a simple modification for the TC-1 clone to make it work with the k/m-firmware. The control MCU U4 is replaced by a small circuit with two transistors. The best way seems to be to use thin enamel wire and hot glue. The ATmega's PD1 is the input for the test button and PD2 the output for the power control. Any jelly bean small signal NPN and PNP are fine.
Thanks for the schematics/modifications!

Any more details regarding
compilation flags/options/...
for the TC-1 firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 12, 2018, 09:33:19 pm
The next m-firmware version will include the settings for the TC-1 (in the "Clones" file).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 13, 2018, 04:28:38 pm
We have a simple modification for the TC-1 clone to make it work with the k/m-firmware. The control MCU U4 is replaced by a small circuit with two transistors. The best way seems to be to use thin enamel wire and hot glue. The ATmega's PD1 is the input for the test button and PD2 the output for the power control. Any jelly bean small signal NPN and PNP are fine.
Yes! :D
It works in simulation! madires thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 13, 2018, 04:39:53 pm
That's cool that you can simulate the whole thing including the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on June 14, 2018, 09:26:01 am
Hello Everyone,

I'm new here but been lurking for a while.

I received the Fish8840TFT in the mail 3 days ago through aliexp.

(https://i.imgur.com/W99iIck.jpg)

I've played with the input voltage and here are the results

Input Voltage / Result
9v = Working (7.8v on display / 320 ma current consumption) 7.8v x 0.320 = 2.88 watt
8.5v = W (7.7v / 300 ma)
8v = W (7.7v / 280 ma)
7.5v = W (7.6v / 260 ma)
7v = W (7.5v / 230 ma)
6.5v = W (7.5v / 190 ma)
6v = W (7.4v / 160 ma)
5.5v = W (7.3v / 110 ma)
5v = W (7.4v / 70 ma)
4.5v = W (7.6v / 50 ma)
4.3v = W (7.6v / 50 ma)
4.2v= W (7.7v / 50 ma)
4.1v = Screen flashes but unit does not switch on. Issue with dropout voltage of zener diode 3.3v (BZX84C3V3). Atmega328 working voltage is 1.8v to 5.5v

Tested on 2200uf capacitor. Zener diodes may probably not work.

Changing input voltage changes the reading data and so needs calibration (join 1+2+3 with small wire and switch on unit. Needs good 100uf capacitor)

Btw, I desoldered the LCD connector flex cable to see whats inside. I would advise readers not to do that since resoldering this back is a pain. IMO, we can desolder/resolder this 3-5 times max before the pitches start disintegrating due to heat. Also set 200-250C heat on solder for this. My resolder attempt was horrible and I had to cover it with tape just to avoid looking at it.

(https://i.imgur.com/672lGUw.jpg)

Some components get warm to hot during operation. When powered by 5v Vin, components run cool (ie, at room temperature)

Next mod is to add lithium battery. BZX84C3V3(3.3v) zener is getting hot because it is connected directly to 9v Vin and dropping 5.7v. A stable Vin should be 5v though 3.6v lithium + a tiny booster (https://www.aliexpress.com/item/1PCS-DC-DC-Boost-Module-0-9V-5V-600mA-Boost-Converter-Step-Up-Module-USB-Mobile/32860779928.html).

(https://i.imgur.com/vFGjreY.jpg)
(https://i.imgur.com/uWoRftK.jpg)

More photos here
https://imgur.com/a/kTM8BPx (https://imgur.com/a/kTM8BPx)
Title: Re: $20 LCR ESR Transistor checker project
Post by: szpila on June 14, 2018, 03:30:11 pm
The next m-firmware version will include the settings for the TC-1 (in the "Clones" file).

Hi madires.
Could you add to source code translation to polish language? I attached a file with translation.
Good luck with further development :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on June 14, 2018, 07:51:12 pm
hello,
I just tried v 1.33m on ay-at clone with 7735 LCD, cryqtal 20 Mhz.
BD237 is detected as NFET, after 3 calibrations I still got big errors on 2200uF capacitor, 22pF seen as 30 pF, some resistors also bad measurements (30K in place of 33K).

IMHO the calibration needs a real procedure from A to Z also for new users.

Reflashed 1.29m, back to correct values(I made always backup for .hex and .eep after calibrating and validating the measurements with verified R/C/Q).

I'm not critic, I just try to make the world a better place :)
Best regards to all,
Ovidiu
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 15, 2018, 01:23:04 pm
I've checked a few large caps with a LCR meter, an 8MHz 328 and 16MHz 644 transistor tester running the latest m-firmware, but wasn't able to reproduce the issue. Could you please PM me your config.h and config_328.h for 1.29m and 1.33m?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 15, 2018, 02:49:47 pm
Here's the complete modification package for the TC-1:
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on June 15, 2018, 10:06:24 pm
Here's the complete modification package for the TC-1:

Nice work madires  :-+ At least now when I kill my current atmega I will have a way to reuse the TC-1   :)  and maybe with further development I might just scrap the original software for
this user friendly upgradable one.  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: joeyjoejoe on June 15, 2018, 10:37:46 pm
Is there some sort of modification to the Fish8840TFT to prevent the 3v3 regulator from blowing up when flashing it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on June 18, 2018, 04:43:01 pm
try to add a 3.7V (or 4.1) zener between 3v3 reg output and GND-anode to GND, and a schottky diode between input and output of 3v3 regulator with anode on out and cathode on input.maybe a 5v6 zener on input, then you're immortel.I think the spikes kill the 3v3 reg.
best regards,ovidiu
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 19, 2018, 07:00:44 pm
While checking the configuration for the TC-1 I've noticed that the power supply seems to need additional or larger decoupling caps. I also had to lower the voltage of the brown-out detection (e-fuse).
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on June 22, 2018, 04:28:13 am
Just for curiosity's sake, I decided to photograph the ATMEGA that came with my component tester alongside a brand new one I just ordered from Microchip. They look very similar, except the laser markings on the new chip are much better quality.

Are there any tests for identifying counterfeits?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on June 22, 2018, 04:29:32 am
(previous post size was exceeded)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 22, 2018, 09:46:46 am
Hasn't the one with the higher quality markings the later production date stamp? Maybe they got new lasers. The markings on my Atmel MCUs with on older production date are also a bit weak.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on June 22, 2018, 07:23:00 pm
You could be right.

Top on says '1725' ... 25th week of 2017 I'm guessing.

Bottom one (came with tester): 35th week of 2015.
The chip factory to eBay seller time would have to be relatively quick. I ordered my tester on the 50th week of 2015.
Title: Re: $20 LCR ESR Transistor checker project
Post by: edavid on June 23, 2018, 04:44:01 am
Just for curiosity's sake, I decided to photograph the ATMEGA that came with my component tester alongside a brand new one I just ordered from Microchip. They look very similar, except the laser markings on the new chip are much better quality.

Are there any tests for identifying counterfeits?

No, because one has ever seen a counterfeit AVR chip  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on June 23, 2018, 03:41:22 pm
Just for curiosity's sake, I decided to photograph the ATMEGA that came with my component tester alongside a brand new one I just ordered from Microchip. They look very similar, except the laser markings on the new chip are much better quality.

Are there any tests for identifying counterfeits?

No, because one has ever seen a counterfeit AVR chip  :-//
There were cases of companies being sold duds instead of AVR chips (https://www.sparkfun.com/news/350 (https://www.sparkfun.com/news/350)), which is what some people might be referring to. But you are right, there are no known cases of working (or semi-working) AVR chips (unlike, say, many buck regulators chips, where the fakes work enough like the original to pass a cursory test; pretty much any buck regulator from eBay China is built on a counterfeit chip)

Chip rebadging is also common: take a chip, erase the markings, replace the markings with the ones for the came chip with higher specs (i.e. an Intel processor rebadged to look like a faster version, or higher temp tolerances)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ziplock9000 on June 23, 2018, 04:59:26 pm
I just bought this one (M328P LCR-T4, MTester) from Amazon UK for £5.72 GBP
https://www.amazon.co.uk/SODIAL-Quality-Transistor-Capacitance-Inductance/dp/B015X8Q1DS/ref=sr_1_fkmr1_1?s=industrial&ie=UTF8&qid=1529772441&sr=1-1-fkmr1&keywords=SODIAL%28R%29+High+Quality+Brand+New+LCR-T4+ESR+Meter+Transistor+Tester+Diode+Triode+Capacitance+SCR+Inductanc (https://www.amazon.co.uk/SODIAL-Quality-Transistor-Capacitance-Inductance/dp/B015X8Q1DS/ref=sr_1_fkmr1_1?s=industrial&ie=UTF8&qid=1529772441&sr=1-1-fkmr1&keywords=SODIAL%28R%29+High+Quality+Brand+New+LCR-T4+ESR+Meter+Transistor+Tester+Diode+Triode+Capacitance+SCR+Inductanc)

It seems to be identical to the one in Dave's video. It identifies itself as an MTESTER on the LCD and LCR-T4 on the Amazon page, but with no firmware version numbers at all. I've just ran some very cursory tests and it seems to fail on a BF245A JFET, which it thinks is a BJT (shown in the attached images below). I need to do more extensive testing and post them here if anyone cares?

I'd like to identify and update the firmware if it helps with component identification and accuracy. I'll need to dig through this monster thread. I've seen the firmware listing (possibly) on www.mikrocontroller.net (http://www.mikrocontroller.net), but I'd need more help I think :-\

UPDATE: I found the post https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867)




Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 24, 2018, 10:00:51 am
k-firmware: mega328_T3_T4_st7565 or mega328_T4_v2_st7565
m-firmware: see Clones file for the settings for T3/T4
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on June 27, 2018, 07:08:17 am
The next m-firmware version will include the settings for the TC-1 (in the "Clones" file).
I  may be looking in the wrong place, can someone provide a link to the file Madires mentions.

I am trying to upgrade one of my TC1 units.  I have attached a schematic I put together, it may not be 100% but should be close, let me know if you think there are errors and I can check.

I have upgraded the processor to a ATMEGA644PA-AU.  Will probably ask questions as I try and figure out how to build config files and choose correct options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 27, 2018, 10:47:03 am
The k and m firmware won't run on an unmodified TC-1 because of the additional MCU U4. But it's possible to replace U4 with a small circuit which I've posted on this page. Also I've run into problems with the TC-1's power supply, it's not stable. The "Clones" file is in the m-firmware's tgz archive and lists settings for a few clones and some hints. And here's the wiring of the LCD for your diagram:

PB7 (SCK)  - LCD SCK
PB6 (MISO) - LCD SDA
PB5 (MOSI) - LCD A0
PB4             - LCD /RESET

If the designer of the clone would have payed more attention to the pin assignment the TC-1 would be able to use the hardware SPI for driving the LCD.
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on June 27, 2018, 12:31:28 pm
This is another time & place where mentioning some sellers to buy from , or not , to help avoid buyers from ending up with problems ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 27, 2018, 01:08:57 pm
The AY-AT clone is still the best choice at the moment, IMHO. I wonder why none of the Chinese clone manufacturers has contacted us for collaboration yet. They could sell a nice clone with an ATmega644 and a few hardware options, and we would take care about the firmware as we already do.
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on June 27, 2018, 02:36:50 pm
Thanks madires for the replies .
The 1st one I bought is deep in my ebay to find , the one I got last week is this one https://www.ebay.com/itm/2017-DIY-KITS-GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM/182586325643?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 (https://www.ebay.com/itm/2017-DIY-KITS-GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM/182586325643?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649)
I must have mixed up , the too many I was looking at , I was expecting one with the clear case , oh well .
And now you mention another hope-full coming out with the ATmega644 , maybe the 3rd .
On the one I bought , hopefully to help someone , they had a couple of electrolytic caps - that were to tall - they held the display from fully seating into the socket , also could not reach the stand-offs for hold down .
Then the screws for the stand-offs heads could reach solder points on the other side of board .
The kinda stuff that if a builder knew in advance , you could mount the caps horizontal & glue down - rather than like I did after the build - try to seat display and then found issues , dismount caps add wire to mount horizontal vs. vertical .
Now have to find a way to calibrate - this has internal calibrate and is off , do not remember how good the matching values can be .
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: b_force on June 27, 2018, 02:42:49 pm
I'd like to identify and update the firmware if it helps with component identification and accuracy. I'll need to dig through this monster thread. I
UPDATE: I found the post https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867)
Maybe it's an idea that someone actually can make a summary, make a new topic and make that as a sticky?
I have the idea that a few people here know exactly what's going on and what/where to find everything.
But to me it's also a huge maze to go through.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ziplock9000 on June 27, 2018, 02:45:33 pm
I'd like to identify and update the firmware if it helps with component identification and accuracy. I'll need to dig through this monster thread. I
UPDATE: I found the post https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg659867/#msg659867)
Maybe it's an idea that someone actually can make a summary, make a new topic and make that as a sticky?
I have the idea that a few people here know exactly what's going on and what/where to find everything.
But to me it's also a huge maze to go through.
Yeah it's a bit confusing for me too although I'm starting to get my head around it. Especially since I have to set up a compile environment and edit make files. I'm surprised nobody has set up a self contained wizard that asks you a few questions, has a self contained compiler and uploads the end product to the MCU. All nicely wrapped up in a single download and .exe
Title: Re: $20 LCR ESR Transistor checker project
Post by: UKTech on June 27, 2018, 11:27:38 pm
Hi all
I've been lurking now for quite sometime but thought I'd better register into this forum and thank everyone for all the knowledge that I've gained and a special thanks to madires and KH for all the support that is given to us all. What a fantastic forum subject we've got. I now have two of these little mighty meters and just ordered the third, an AY-AT clone with the colour screen and the rotary encoder, so will be updating as soon as it arrives on the slow boat. The last one was a TC4 and the other is one of the early ones that I've just put into the old test gear box.
I'm an old timer but enjoyed electronics way back when I was conciderably younger and transistors were the thing, but at least I saw the first i.c.'s come in, what fun were those 555 things. I decided that when I retired I'd pick this hobby up again and also have a play with 3DPrinting, well I've played quite well with the Tevo Black Widow 3DPrinter and I've had built a nice shed for the electronics, I've spent quite sometime with the Arduino, so now to play.
I can honestly say that I've just finished reading all 195 pages and will rescan to pick up the parts that I've tagged that are of special interest to me.
Sorry to have taken up so much of the page but just had to say.......
Thanks again to everyone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on June 28, 2018, 03:45:47 am
The k and m firmware won't run on an unmodified TC-1 because of the additional MCU U4. But it's possible to replace U4 with a small circuit which I've posted on this page. Also I've run into problems with the TC-1's power supply, it's not stable. The "Clones" file is in the m-firmware's tgz archive and lists settings for a few clones and some hints. And here's the wiring of the LCD for your diagram:

PB7 (SCK)  - LCD SCK
PB6 (MISO) - LCD SDA
PB5 (MOSI) - LCD A0
PB4             - LCD /RESET

If the designer of the clone would have payed more attention to the pin assignment the TC-1 would be able to use the hardware SPI for driving the LCD.
I agree it is annoying that they don't publish their changes to the code or schematic.  Given that there are a lot of these units out there, which will most likely end up faulty and people want to get them going or upgrade them with newer features functions: Isn't it possible to modify the "m" version code to support the configuration utilising U4.  I am happy to try and give the changes a go.  I have a working TC1 with original 324 chip I can use to check things (take measurements) and also as a reference. I have another one I am trying to modify which now has a blank 644 in place.

For reference the 2 PCB's appear to be almost the same.  Only differences I have spotted are (as per my schematic in previous post) C11 now has a second Cap C12 in parallel and any higher numbered Caps have been renumbered by +1 (C12-C23 become C13-C24).  EN pad had been moved from the edge to near the middle.  D2 is physically smaller.  All of the other traces and vias and components on the PCB appear to be placed and route exactly the same.  I will draw an updated diagram and post if it anyone wants it.  I can also take a picture of the 2 different but similar PCB's and post those if people are interested.

I do want to get my second unit with the 644 working with more of the new code features eventually, also very keen to try and contribute in any way I can to help others.  I have adequate test gear for the task (lab bench supplies, 4ch digital and analogue scopes, 5 1/2 digit mm, basic signal generator, simple logic analyzers, tools for surface and PTH rework, AVR JTAGICE3...).

I am new to the source repository and find this thread very useful but still not sure which repository version to download as a starting point for converting a TC1 with ATMEGA 324.  I downloaded ComponentTest 1.33m and it does not have an archive folder, so I must have the wrong file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on June 28, 2018, 06:06:59 am
Download all from start page


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Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 28, 2018, 12:59:17 pm
Maybe it's an idea that someone actually can make a summary, make a new topic and make that as a sticky?
I have the idea that a few people here know exactly what's going on and what/where to find everything.
But to me it's also a huge maze to go through.

jakeisprobably started working on a FAQ/how-to a while ago but I don't know the current status.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 28, 2018, 01:02:41 pm
I can honestly say that I've just finished reading all 195 pages and will rescan to pick up the parts that I've tagged that are of special interest to me.

Wow! I hope it wasn't too boring ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 28, 2018, 01:22:40 pm
Isn't it possible to modify the "m" version code to support the configuration utilising U4.

Unfortunately U4 doesn't simply simulate a button press or read the power-on signal, it uses a serial protocol to communicate with the ATmega.

I will draw an updated diagram and post if it anyone wants it.  I can also take a picture of the 2 different but similar PCB's and post those if people are interested.

I'm sure some users would be interested in your diagram and the pictures.

I am new to the source repository and find this thread very useful but still not sure which repository version to download as a starting point for converting a TC1 with ATMEGA 324.  I downloaded ComponentTest 1.33m and it does not have an archive folder, so I must have the wrong file.

The "Clones" file is part of the ComponentTester-1.33m.tgz archive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: b_force on June 28, 2018, 01:52:52 pm
Maybe it's an idea that someone actually can make a summary, make a new topic and make that as a sticky?
I have the idea that a few people here know exactly what's going on and what/where to find everything.
But to me it's also a huge maze to go through.

jakeisprobably started working on a FAQ/how-to a while ago but I don't know the current status.
Just a post were people van even find the links for downloads and the global differences?
At this moment people need to read through a whole bunch of pages to discover that the firmware can even be changed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on June 28, 2018, 06:37:15 pm
At this moment people need to read through a whole bunch of pages to discover that the firmware can even be changed.
Everybody who says this clearly didn't try. It's on the first page
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on June 29, 2018, 05:30:15 am
OK, I have just finished a marathon post read of all 196 pages.  I did skim read but was trying to focus on the progress of the various hardware/software versions not specific faults.

I have hopefully read all the TC1 posts.  Seems several have been down this road before me.  I would prefer to not have to change U4 for now and try to see if we can understand it.

My plan is to try and do the following (for TC1 style):
Verify what the supply voltages are like on a working unmodified unit (using scope and 5 1/2 digit DMM measurements);
Update my schematic with more info as provided by previous posts;
Make the previously suggested mods to my second unit (now sporting a 644) 0.1% test resistors, replace 78L05 vreg and/or TL431 vref chips;
Make improvements to 5v rail on second unit as previuosly suggested by Madires;
Look at any variations on U4 signals (long press/short/double press) from previous waveforms posted;
Try and decode the power on protocol between U4 and U1.

Hope that might help to confirm this clones strange behaviour and make it a working part of the clone configs info.  Please let me know if any of it is useful or just a waste of time.

If there is anything else needed I have missed regarding the TC1 that I can possibly do please let me know.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on June 29, 2018, 12:20:48 pm
I am trying to work out what is available as a replacement part to improve the 5v regulation on the TC1 from the 78L05 SOT-89 they use.

Would anyone with knowledge of the tolerance requirements cast your eyes over the attached specs of a couple of pin compatible SOT-89 LDO's with better line and load regulation I have found?

Below are links to the data sheets, could not attach them (not for lack of trying, they were over the size limit allowed):
Element14, LD2981 http://www.farnell.com/datasheets/2310115.pdf?_ga=2.139301427.1894826597.1530201477-1167880404.1500891526 (http://www.farnell.com/datasheets/2310115.pdf?_ga=2.139301427.1894826597.1530201477-1167880404.1500891526)
Mouser/Digikey AP7381 https://au.mouser.com/datasheet/2/115/AP7381-1220674.pdf (https://au.mouser.com/datasheet/2/115/AP7381-1220674.pdf)

If these look suitable I will order the one from Element14 first and see how they perform.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on June 29, 2018, 12:30:25 pm
I am trying to work out what is available as a replacement part to improve the 5v regulation on the TC1 from the 78L05 SOT-89 they use.

Would anyone with knowledge of the tolerance requirements cast your eyes over the attached specs of a couple of pin compatible SOT-89 LDO's with better line and load regulation I have found?

Below are links to the data sheets, could not attach them (not for lack of trying, they were over the size limit allowed):
Element14, LD2981 http://www.farnell.com/datasheets/2310115.pdf?_ga=2.139301427.1894826597.1530201477-1167880404.1500891526 (http://www.farnell.com/datasheets/2310115.pdf?_ga=2.139301427.1894826597.1530201477-1167880404.1500891526)
Mouser/Digikey AP7381 https://au.mouser.com/datasheet/2/115/AP7381-1220674.pdf (https://au.mouser.com/datasheet/2/115/AP7381-1220674.pdf)

If these look suitable I will order the one from Element14 first and see how they perform.
You don't need ldo you need precision regulators I guess.


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Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on June 29, 2018, 01:21:05 pm
You don't need ldo you need precision regulators I guess.

Most precision vregs are around +-2% which is not as good as the ones suggested like MCP1702.  The ones I suggested are better precision and can be soldered directly in place of the TC1's 78L05, the MCP1702 like most others have different pinouts are not a direct replacement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on June 29, 2018, 01:48:57 pm
pinout is not really the point.you have tons of precision regs and you find easy some place to adapt. the realy issue is in fact temperature drift... I remember lt1461 series as example

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Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 29, 2018, 02:12:37 pm
Some thoughts about selecting a voltage regulator for the Transistor Tester:
- It should handle 100mA (MCU) plus whatever is needed for display and hardware options.
  The MCU does need much less in average but a few checks use high currents very briefly.
- It should be able to handle rapid load changes (sleep mode, normal operation, high current checks, hardware options).
- It should have a good regulation to keep the voltage stable under changing loads.
- It doesn't need to be one with a low output voltage tolerance but such a regulator would improve the tester's accuracy.

We recommend the MCP1702 (250mA, 0.4%, about EUR 0.60). Affordable and much better than a LM78L05 plus TL431.

This brings us to the external voltage reference. The purpose of the reference is to determine Vcc and therefore it should have a tolerance at least one order of magnitude better than the voltage regulator's tolerance. A TL431 is ok for a 78L05, a LM4040 would be better. If you use a MCP1702 you don't need a reference at all unless you're a voltage nut :).

I hope this helps with the selection of the voltage regulator and external voltage reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on June 29, 2018, 02:24:27 pm
I don't agree,microchip says in datasheet Vout could be bttween 5V -3% and 5V+3% for MCP1702.No way 0.4%.
And I saw this often confirmed in real life.
That's why I proposed the LT.just as example.
Regards,ovidiu


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Title: Re: $20 LCR ESR Transistor checker project
Post by: UKTech on June 29, 2018, 09:51:08 pm
madires   "Wow! I hope it wasn't too boring"

To be honest it has been a good read, it's always good to read, and a day without learning is a day wasted, that's how I see it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pierreraymondrondelle on June 30, 2018, 08:05:42 am
read again, the folowing is an abstract of the Microchip MCP1702 datasheet:

"The MCP1702 is capable of delivering 250 mA with
only 625 mV (typical) of input to output voltage
differential (VOUT = 2.8V). The output voltage tolerance
of the MCP1702 is typically ±0.4% at +25°C and ±3%
maximum over the operating junction temperature
range of -40°C to +125°C. Line regulation is ±0.1%
typical at +25°C".
Do you really use electronic circuits at home and operate your tester over this range ?
EDIT:
reading further, @25°C, min and max Output Voltage tolerance remains within +-2% !
Title: Re: $20 LCR ESR Transistor checker project
Post by: b_force on June 30, 2018, 09:19:12 pm
At this moment people need to read through a whole bunch of pages to discover that the firmware can even be changed.
Everybody who says this clearly didn't try. It's on the first page
I think it's more clearly that the amount of information is overwhelming.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on July 01, 2018, 12:54:01 pm
read again, the folowing is an abstract of the Microchip MCP1702 datasheet:

"The MCP1702 is capable of delivering 250 mA with
only 625 mV (typical) of input to output voltage
differential (VOUT = 2.8V). The output voltage tolerance
of the MCP1702 is typically ±0.4% at +25°C and ±3%
maximum over the operating junction temperature
range of -40°C to +125°C. Line regulation is ±0.1%
typical at +25°C".
Do you really use electronic circuits at home and operate your tester over this range ?
EDIT:
reading further, @25°C, min and max Output Voltage tolerance remains within +-2% !
Have your even seen a pro calculating regarding 'typically' values?
If anyone bother to change something in this meter should not regard for 2 euros cheaper but in components with slow drift and higher precision, in fact I do so.
And second I prefer leave microchip power products to begginers, they never give satisfaction.have you seen lot of microchip power stuff in laptops for example?have you wondered why they use LT or others?
You can recomend what you consider,as I do based on my own experience.
And 'it's pin to pin compatible' also I don't even consider for a 3 pin device, I just find a place for the replacement.
Mods is for advertised people, who can switch pin 2 with pin 3 if necessary.
I'll never reply to this kind of post,it's not professional, just ego stuff.
Ovidiu


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Title: Re: $20 LCR ESR Transistor checker project
Post by: CNC Engineer on July 01, 2018, 06:34:57 pm
I saw the TC-1 but also a TC-6 and a TC-7.
Does anyone know the differences?

Thanks, CNC Engineer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 02, 2018, 03:10:41 pm
CNC Engineer,these devices imeet very similar functionality and differ only in the display which is used. LCR-TC1, LCR-TC7-colored display. LCR-TC6 - the monochrome display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on July 03, 2018, 07:29:05 pm
At this moment people need to read through a whole bunch of pages to discover that the firmware can even be changed.
Everybody who says this clearly didn't try. It's on the first page
I think it's more clearly that the amount of information is overwhelming.

 :'(
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on July 07, 2018, 09:37:24 am
Food for thought.. I was thinking about an alternate "headless" technician version of the AVR tester:

Why not send display data via USB serial protocol and have an easy to read screen app on the host that stores all the graphics (to free-up AVR memory allowing an on-board 5v-to-??v boost convertor to run tests at higher voltages and higher current?

But then again, maybe it's been done? Maybe there's also a USB OTG version?  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 07, 2018, 10:39:08 am
The next m-firmware version will have a VT100 display driver (incl. color support) which outputs everything via a TTL serial interface. Only the fancy symbols are missing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on July 07, 2018, 11:59:23 am
So it's conceivable a variant could send simplistic raw data, symbol number and pin order then?

IMHO, ditching display for USB OTG (w/ DC-DC step-up) and Android app would make this more usable in 3rd world countries
 (9v cells cost precious $ and many basic tech's have a cell-phone but no PC)

* Without symbols precious AVR memory could run PWM step-up supply voltage (but I really don't know if it's feasible..)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 08, 2018, 10:06:32 am
Actually it should be simple to extract the component type and its pinout from the serial output. Another way would be to enable the remote commands to retrieve type and pinout directly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on July 08, 2018, 11:07:08 am
Actually it should be simple to extract the component type and its pinout from the serial output. Another way would be to enable the remote commands to retrieve type and pinout directly.
So one question remains then: after deleting all symbols/cost &requirements for LCD, is there enough code room and AVR performance left to take the 5v from USB OTG and boost it high enough to power a regulator for test voltages? *Edit: NJM78L09UA-TE1 is about 20cents, so with a USB connector, inductor, transistor, etc.. mfg's can produce at equal cost.

Who knows, maybe even total screen control can eliminate the button and one might conceive a way to do AVR firmware updates too. This is a tech-tool and most of us have phones and PC's and don't like constantly buying 9v batteries. Yes, stand-alone is good (I've gone through 3 already) but I'd prefer a USB version if it existed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 08, 2018, 03:07:35 pm
I'd use a high efficient boost converter chip to boost the USB's 5V or a LiPo's 3.7V and add a LDO for the 5V post-regulation. For some components a switchable high test voltage would interesting but this would also require a more complex input circuitry and an external ADC. With the next m-firmware version you can remove the display and use the freed I/O pins for a bit-bang serial interface. Add an USB2serial adapter and a boost converter plus an optional LiPo incl. charger chip (see the TC-1 clone for example), and use a simple VT100 terminal program on your PC or smartphone. Or go for a Bluetooth2serial adapter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on July 08, 2018, 03:25:19 pm
Certainly going headless, button-less and USB-OTG seems a good conversation to start, but maybe not here in a support thread.
I don't think I'm qualified to start a thread on it, but surely others might weigh-in on the merits (but I like your BT idea..)  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: MAntunes on July 10, 2018, 02:24:33 am
Hi guys!
I'm looking to buy one of these testers but there is so much stuff on eBay that I don't know what to choose.
Can you recommend me the best one?
Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 10, 2018, 02:31:33 am
Get the AY-AT. See pictures and component upgrade info in this post: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MAntunes on July 10, 2018, 05:55:29 pm
Get the AY-AT. See pictures and component upgrade info in this post: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025)

So, something like this? https://www.ebay.com/itm/Mega328-Transistor-Tester-LCR-Capacitance-ESR-Meter-PWM-DIY-TFT-LCD-Generator/311969609837?hash=item48a2d6786d:m:mdvjYjvVD-0l3a4DNR6HucA (https://www.ebay.com/itm/Mega328-Transistor-Tester-LCR-Capacitance-ESR-Meter-PWM-DIY-TFT-LCD-Generator/311969609837?hash=item48a2d6786d:m:mdvjYjvVD-0l3a4DNR6HucA)

Thank you!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 10, 2018, 09:45:05 pm
Yes, that appears to be an AY-AT.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gary.M on July 11, 2018, 01:09:24 am
Just bought one of these from AliExpress. How much Russian text should there be? I have quite a lot of text in Russian, although the test output is in English.
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on July 12, 2018, 07:30:28 am
Continuing from this post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1607518/#msg1607518), the st7735 is getting powered from two sources.

(http://tinyimg.io/i/G94zlXX.png)

Can I replace 3v3_z14 zener with a 1/2w watt resistor? But I dont know the current consumption of pin 10+11. Could not find it in the datasheet.

----------------

I looked at the schematic posted here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1532846/#msg1532846). There are two types of st7735 - a readymade version with male headers and the bare lcd version(found in fish8840tft) which is cheaper to buy from aliexp. The person who made this schematic has used the first version and using an LDO(ams1117 3.3v). He/she has also added a few higher value capacitors(marked in red).
Title: Re: $20 LCR ESR Transistor checker project
Post by: MasGanBro on July 12, 2018, 09:49:43 am
Hello, first post here. Apologize for bad english

My bro give me this this (https://ecs7.tokopedia.net/img/product-1/2018/2/13/892389/892389_57f12f3a-3edc-4440-82aa-dc04c2ad0c15_1000_1000.jpg). T4, right?
The problem is :
- tester give the wrong voltage. I mean, too much voltage drop. In my cheap multimeter, bat 9.6v. In this tester, around 7.8v
- this is im not sure, because i cant compare. Tester give wrong pin for jfet. Sometimes detect as npn

What i did
- selftest, jumper 3 pin in zif socket + 220n after that
still problem.

what i must do then?
the closest search, give me tom666 post (https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/msg879842/#msg879842). I think, still have arduino uno. Its right?

or any other option for the latest firmware? what the right (https://github.com/svn2github/transistortester/tree/master/Software/trunk)? its hard to learn how to flash to that?

notes : Me are noob in electronic.

Big Thanks.
Febri
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 12, 2018, 10:32:14 am
Can I replace 3v3_z14 zener with a 1/2w watt resistor? But I dont know the current consumption of pin 10+11. Could not find it in the datasheet.

This would be a bad idea since the LCD isn't a constant load. The current consumption changes with the operation mode and a few settings. A zener or LDO is the right way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 12, 2018, 10:47:39 am
T4, right?

Yep!

what i must do then?
the closest search, give me tom666 post (https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/msg879842/#msg879842). I think, still have arduino uno. Its right?

Yes, you can use an Arduino as programmer.

or any other option for the latest firmware? what the right (https://github.com/svn2github/transistortester/tree/master/Software/trunk)? its hard to learn how to flash to that?

k-firmware: mega328_T3_T4_st7565 or mega328_T4_v2_st7565
m-firmware: see Clones file for settings for the T3/T4 clone and compile the firmware (Software/Markus)

You'll find tons of guides about programming an ATmega MCU in the internet. There are also a few guides in this thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on July 12, 2018, 12:29:38 pm
Can I replace 3v3_z14 zener with a 1/2w watt resistor? But I dont know the current consumption of pin 10+11. Could not find it in the datasheet.

This would be a bad idea since the LCD isn't a constant load. The current consumption changes with the operation mode and a few settings. A zener or LDO is the right way.
Understood

-----

I made the schematic of fish8840tft(using this (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1532846/#msg1532846) post) + mt3608 module. Im attaching the files(altium) if anyone is interested in poking around. Kindly correct mistakes if any.

edit 14 july

fish.zip = fish8840 + mt3608 (smd 328p)
karl.zip = karl heinz kubbeler 1.13k + mt3608 + st7735 (dip 328p)

note: resistors are in standing position
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on July 14, 2018, 08:25:21 pm
Hello everyone,

I have an old transistor tester that has the 3 screw type connector. Is there anyone that know if a adapter board exists for me to install a zif socket instead for the 3 hole screw type connector?

Thank you to all!
Title: Re: $20 LCR ESR Transistor checker project
Post by: UKTech on July 14, 2018, 09:50:22 pm
Help please!
I have an AY-AT 328 tester (Supposedly the Bees Knees at the moment) and it’s almost built, but I’m in need of some info on the small 6 legged device that is an SMD and is situated with the other 2 SMDs at the bottom of the board and is marked with MC5 on the top of it. It is between the left blue 2way Connector Block and the Clamping Tester Block (Sorry, don’t have the name to hand).
Any help would be much appreciated.  Many thanks anyway.

John
Title: Re: $20 LCR ESR Transistor checker project
Post by: UKTech on July 14, 2018, 09:57:12 pm
rddube
Hello everyone,

I have an old transistor tester that has the 3 screw type connector. Is there anyone that know if a adapter board exists for me to install a zif socket instead for the 3 hole screw type connector?

Thank you to all!



Hi
I wouldn't have thought that you would have the space anywhere on the board to fit one. Another way would be to fit speaker clamp connectors as they are smaller. Hope that helps.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on July 15, 2018, 01:22:21 am
rddube
Hello everyone,

I have an old transistor tester that has the 3 screw type connector. Is there anyone that know if a adapter board exists for me to install a zif socket instead for the 3 hole screw type connector?

Thank you to all!



Hi
I wouldn't have thought that you would have the space anywhere on the board to fit one. Another way would be to fit speaker clamp connectors as they are smaller. Hope that helps.

Yah the space is there...all I would need is a daugtherboard to take a 14 pin connector down to 3 .........must exist?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 15, 2018, 07:25:15 am
Help please!
I have an AY-AT 328 tester (Supposedly the Bees Knees at the moment) and it’s almost built, but I’m in need of some info on the small 6 legged device that is an SMD and is situated with the other 2 SMDs at the bottom of the board and is marked with MC5 on the top of it. It is between the left blue 2way Connector Block and the Clamping Tester Block (Sorry, don’t have the name to hand).
Any help would be much appreciated.  Many thanks anyway.

John

The SVR05-4 is a TVS diode array and used as part of a protection circuit. See:
http://m.littelfuse.com/~/media/electronics/datasheets/tvs_diode_arrays/littelfuse_tvs_diode_array_srv05_datasheet.pdf.pdf (http://m.littelfuse.com/~/media/electronics/datasheets/tvs_diode_arrays/littelfuse_tvs_diode_array_srv05_datasheet.pdf.pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on July 15, 2018, 06:26:40 pm
Hello everyone,

I have an old transistor tester that has the 3 screw type connector. Is there anyone that know if a adapter board exists for me to install a zif socket instead for the 3 hole screw type connector?

Thank you to all!

Bump, anybody?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on July 16, 2018, 12:52:32 am
The ZIF socket wiring just shorts some of the pins together as shown in the various circuits posted.

You could just solder the ZIF to some vero or perf board for mounting and then wire the pins together (as per the circuits) and solder the 3 wires to take back to your tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on July 16, 2018, 01:05:42 am
Continuing from this post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1607518/#msg1607518), the st7735 is getting powered from two sources.

(http://tinyimg.io/i/G94zlXX.png)

Can I replace 3v3_z14 zener with a 1/2w watt resistor? But I dont know the current consumption of pin 10+11. Could not find it in the datasheet.

----------------

I looked at the schematic posted here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1532846/#msg1532846). There are two types of st7735 - a readymade version with male headers and the bare lcd version(found in fish8840tft) which is cheaper to buy from aliexp. The person who made this schematic has used the first version and using an LDO(ams1117 3.3v). He/she has also added a few higher value capacitors(marked in red).
I think the circuit drawing you inserted is not correct.  Based on the pinouts and there being no current limiting resistor as part of the voltage divider (together with the Zener) for the 3.3V supply it is unlikely to be a Zener but more likely a 3.3V LDO regulator (like the amd1117 3.3v you mentioned later).  You can't replace it (even if it is drawn out correctly) with a resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UKTech on July 16, 2018, 03:13:46 pm
Help please!
I have an AY-AT 328 tester (Supposedly the Bees Knees at the moment) and it’s almost built, but I’m in need of some info on the small 6 legged device that is an SMD and is situated with the other 2 SMDs at the bottom of the board and is marked with MC5 on the top of it. It is between the left blue 2way Connector Block and the Clamping Tester Block (Sorry, don’t have the name to hand).
Any help would be much appreciated.  Many thanks anyway.

John

The SVR05-4 is a TVS diode array and used as part of a protection circuit. See:
http://m.littelfuse.com/~/media/electronics/datasheets/tvs_diode_arrays/littelfuse_tvs_diode_array_srv05_datasheet.pdf.pdf (http://m.littelfuse.com/~/media/electronics/datasheets/tvs_diode_arrays/littelfuse_tvs_diode_array_srv05_datasheet.pdf.pdf)

Thanks for the info, it was in front of my eyes all the time, thought that number was something else to do with the board but there you go. I'd have never got it as I'd already dismissed it previously. Your help is much appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MasGanBro on July 17, 2018, 04:17:38 am
Hello,

Special thanks to madires and tom666, i can flash some friend tester  ;D
sorry, too excited, eureka moment noob. hehe.

but,
1 tester, T4 no strip grid, have blank lcd after flashing  |O
backlight still on, but no output

somehow, in W10, success if add \
Code: [Select]
REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)
avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m

below output from cmd. Run on W10
Code: [Select]
Microsoft Windows [Version 10.0.17134.165]
(c) 2018 Microsoft Corporation. All rights reserved.

C:\Users\hore>cd C:\Users\hore\Downloads\Anto\LCR-Tx_v1.12k_r508_EN

C:\Users\hore\Downloads\Anto\LCR-Tx_v1.12k_r508_EN>FlashK.bat

C:\Users\hore\Downloads\Anto\LCR-Tx_v1.12k_r508_EN>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\LCR-Tx_v1.12k_r508_EN>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m
avrdude: ser_open(): can't set com-state for "\\.\COM4"

avrdude done.  Thank you.


C:\Users\hore\Downloads\Anto\LCR-Tx_v1.12k_r508_EN>FlashK.bat

C:\Users\hore\Downloads\Anto\LCR-Tx_v1.12k_r508_EN>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\LCR-Tx_v1.12k_r508_EN>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: erasing chip
avrdude: reading input file "TransistorTester.hex"
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: writing flash (28872 bytes):

Writing | ################################################## | 100% 32.25s

avrdude: 28872 bytes of flash written
avrdude: verifying flash memory against TransistorTester.hex:
avrdude: load data flash data from input file TransistorTester.hex:
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: input file TransistorTester.hex contains 28872 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 18.39s

avrdude: verifying ...
avrdude: 28872 bytes of flash verified
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (15 bytes):

Writing | ################################################## | 100% 0.80s

avrdude: 15 bytes of eeprom written
avrdude: verifying eeprom memory against TransistorTester.eep:
avrdude: load data eeprom data from input file TransistorTester.eep:
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: input file TransistorTester.eep contains 15 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 0.08s

avrdude: verifying ...
avrdude: 15 bytes of eeprom verified

avrdude: safemode: Fuses OK (E:FC, H:D9, L:F7)

avrdude done.  Thank you.

C:\Users\hore\Downloads\Anto\LCR-Tx_v1.12k_r508_EN>


Didnt compare that output with successfull flash
So, what happen? trouble with lcd? on what? and how to fix?

Big Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 17, 2018, 11:25:35 am
Code: [Select]
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (15 bytes):

That should be much more (about 700 -1000 bytes).
Title: Re: $20 LCR ESR Transistor checker project
Post by: MasGanBro on July 18, 2018, 02:37:29 pm
That should be much more (about 700 -1000 bytes).

Did flash some friend T4 (strip) and my T4 (no strip).
cmd output :
Code: [Select]
Microsoft Windows [Version 10.0.17134.165]
(c) 2018 Microsoft Corporation. All rights reserved.

C:\Users\hore>cd C:\Users\hore\Downloads\Anto\FF

C:\Users\hore\Downloads\Anto\FF>FlashK.bat

C:\Users\hore\Downloads\Anto\FF>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\FF>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x000000 (retrying)

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x000000 (retrying)

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x000000
avrdude: Yikes!  Invalid device signature.
         Double check connections and try again, or use -F to override
         this check.


avrdude done.  Thank you.


C:\Users\hore\Downloads\Anto\FF>FlashK.bat

C:\Users\hore\Downloads\Anto\FF>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\FF>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: erasing chip
avrdude: reading input file "TransistorTester.hex"
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: writing flash (31016 bytes):

Writing | ################################################## | 100% 34.64s

avrdude: 31016 bytes of flash written
avrdude: verifying flash memory against TransistorTester.hex:
avrdude: load data flash data from input file TransistorTester.hex:
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: input file TransistorTester.hex contains 31016 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 19.70s

avrdude: verifying ...
avrdude: 31016 bytes of flash verified
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (881 bytes):

Writing | ################################################## | 100% 43.34s

avrdude: 881 bytes of eeprom written
avrdude: verifying eeprom memory against TransistorTester.eep:
avrdude: load data eeprom data from input file TransistorTester.eep:
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: input file TransistorTester.eep contains 881 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 3.52s

avrdude: verifying ...
avrdude: 881 bytes of eeprom verified

avrdude: safemode: Fuses OK (E:FC, H:D9, L:F7)

avrdude done.  Thank you.


C:\Users\hore\Downloads\Anto\FF>

Friend T4, success
My T4, still no output in LCD. I think broken connection or something. Just Led ON only.

since i dont know how to repair this lcd, and more cheap to buy, i go latest option
What you suggest? T4 again or what?

Massive Thanks
MGB 
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on July 18, 2018, 05:14:19 pm
change the default contrast.

i have seen what looked like a dead unit that just had VERY low contrast.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MasGanBro on July 19, 2018, 12:08:23 pm
change the default contrast.

how? i just know how to connect cable and click flash only, Sir
the patient : (https://s15.postimg.cc/p2dx7bviz/IMG_20180719_190210.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 19, 2018, 03:17:44 pm
MasGanBro,try to use an firmware which I have attached in archive.
What will be on the display? Check whether there is power + 5.0B on the 4-6(VCC) th pin of the ATMega328 processor. For check that the firmware works you can insert into the ZIF panel on contacts 1-3(1-2,2-3) any serviceable light-emitting diode - when pressing the Test button it has to blink.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MasGanBro on July 19, 2018, 04:53:28 pm
MasGanBro,try to use an firmware which I have attached in archive.
What will be on the display? Check whether there is power + 5.0B on the 4-6(VCC) th pin of the ATMega328 processor. For check that the firmware works you can insert into the ZIF panel on contacts 1-3(1-2,2-3) any serviceable light-emitting diode - when pressing the Test button it has to blink.

Code: [Select]
Microsoft Windows [Version 10.0.17134.165]
(c) 2018 Microsoft Corporation. All rights reserved.

C:\Users\hore>cd C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>FlashK.bat

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m
'avrdude' is not recognized as an internal or external command,
operable program or batch file.

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>FlashK.bat

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x00ff00
avrdude: Expected signature for ATmega328P is 1E 95 0F
         Double check chip, or use -F to override this check.

avrdude done.  Thank you.


C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>FlashK.bat

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0xff00ff
avrdude: Expected signature for ATmega328P is 1E 95 0F
         Double check chip, or use -F to override this check.

avrdude done.  Thank you.


C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>FlashK.bat

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: erasing chip
avrdude: reading input file "TransistorTester.hex"
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: writing flash (30064 bytes):

Writing | ################################################## | 100% 33.51s

avrdude: 30064 bytes of flash written
avrdude: verifying flash memory against TransistorTester.hex:
avrdude: load data flash data from input file TransistorTester.hex:
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: input file TransistorTester.hex contains 30064 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 19.06s

avrdude: verifying ...
avrdude: 30064 bytes of flash verified
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (871 bytes):

Writing | ################################################## | 100% 42.78s

avrdude: 871 bytes of eeprom written
avrdude: verifying eeprom memory against TransistorTester.eep:
avrdude: load data eeprom data from input file TransistorTester.eep:
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: input file TransistorTester.eep contains 871 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 3.48s

avrdude: verifying ...
avrdude: 871 bytes of eeprom verified

avrdude: safemode: Fuses OK (E:FC, H:D9, L:F7)

avrdude done.  Thank you.


C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>


Whoa. She revive  :o v1.13k  :-+
Big Thanks Mr Indman  ;)
and honestly, still confused to use. And font too big  ;D
Im more simple guy, put in socket and press button.
but i can learn new habits. Hehehe

Thank you Sir. Thank you
===add edit===
Im sorry, i think must hold/long press to measure, like first turn on.
turns out, still just click.

and for same component in sequence, said resistor
we can put in socket and that auto measure, remove, then put next item, auto measure
is that?

tester not wrong again about jfet and can measure small ceramic value. i like it!

but, this happen when test jfet
(https://s15.postimg.cc/s2hg1or8p/IMG_20180720_075510.jpg)
for me, its okay, still see pin in picture
Sorry, i dont know why became portrait  :palm:

for mosfet, 'normal'
(https://s15.postimg.cc/wbm63trx7/IMG_20180720_075603.jpg)

End of morning news.  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: orientalsniper on July 21, 2018, 09:05:58 pm
Hello all, I have the AY-AT Clone (red board).

I just finished building it and the zener diode is heating up! It's marked as 6V8C. Does anyone have any idea why that's happening?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 22, 2018, 12:22:21 am
First, check that it's installed in the correct direction. Measure the voltage across it. If it's around 0.6V (or even less), it's backwards or faulty.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 22, 2018, 08:06:14 am
See also the attachment in: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1673066/#msg1673066
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 22, 2018, 10:16:18 am
but, this happen when test jfet
(https://s15.postimg.cc/s2hg1or8p/IMG_20180720_075510.jpg)
for me, its okay, still see pin in picture

The two '?'s indicate that the FET's drain and source couldn't be detected, i.e. drain and source are likely to be symmetrical. The m-firmware displays an 'x' instead of the '?'.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on July 22, 2018, 08:27:14 pm
Hello everyone,

I have a big question, as I'm about to check capacitors in circuit and there are quite a few on the patient board.

So my question is, which version (M or K) is better for in circuit ESR testing of capacitors?

Many thanks to all the masters!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 23, 2018, 11:07:42 am
Don't ask me! ;) I think the k-firmware's ESR measurement might be slightly more accurate.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 23, 2018, 01:20:50 pm
So my question is, which version (M or K) is better for in circuit ESR testing of capacitors?
Transistor tester can't fully take measurements in circuit!
Even at the C+ESR mode at the outputs  without loading of the device there are voltage impulses + 5B that inadmissibly there is a lot of!
 For measurements in circuit it is necessary to use more specialized devices.IMHO :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: garthk on July 24, 2018, 11:19:15 am
I was going to copy progrock, here, but I've run into trouble with the parts ordering:

My current plan is to order one of  these kits (https://www.aliexpress.com/item/2016-DIY-kits-ATMEAG328-M328-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-PWM-Square-wave-Frequency/32815242766.html)

Then, instead of using all the parts the kit comes with, replace some of them with the parts listed here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025).

(I tidied up the links; any errors are all mine.)

Here's the trouble: Mouser want $25 for shipping to Australia unless I rack up $60 of order, DigiKey seem to want batches of 500, four other suppliers have minimum order sizes of $50-$100, RS have decent 681Ω (https://au.rs-online.com/web/p/products/7546828/) and 475kΩ (https://au.rs-online.com/web/p/products/4878728/) resistors I think I can get away with but don't have stock of the 0.1% voltage reference but I can find that on eBay for $6…  it's a mess.

So, zooming out: will throwing another $20-$50 on parts be this worth the effort, or will that $16 kit from two years ago give me decent enough results?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 24, 2018, 11:38:33 am
Transistor tester can't fully take measurements in circuit!
Even at the C+ESR mode at the outputs  without loading of the device there are voltage impulses + 5B that inadmissibly there is a lot of!
 For measurements in circuit it is necessary to use more specialized devices.IMHO :)

I agree, a dedicated meter for in-circuit ESR would be the best choice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 24, 2018, 11:49:47 am
So, zooming out: will throwing another $20-$50 on parts be this worth the effort, or will that $16 kit from two years ago give me decent enough results?

No, that would be insane! If you get the parts for a few bucks when ordering other stuff anyway then do it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on July 24, 2018, 12:34:13 pm
When people exactly know what to order, search for it on AliExpress too.
I order a lot there for years, because it is cheap (even with shipping cost, if applicable).
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on July 25, 2018, 08:55:52 am
I was going to copy progrock, here, but I've run into trouble with the parts ordering:

Then, instead of using all the parts the kit comes with, replace some of them with the parts listed here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1286025/#msg1286025).

(I tidied up the links; any errors are all mine.)

Here's the trouble: Mouser want $25 for shipping to Australia unless I rack up $60 of order, DigiKey seem to want batches of 500, four other suppliers have minimum order sizes of $50-$100, RS have decent 681Ω (https://au.rs-online.com/web/p/products/7546828/) and 475kΩ (https://au.rs-online.com/web/p/products/4878728/) resistors I think I can get away with but don't have stock of the 0.1% voltage reference but I can find that on eBay for $6…  it's a mess.
[/quote]

I've just returned from picking up my order at Farnell. For $25 I got multiple of all the parts for this, plus some extra pots and MOSFETs for my power supplies repair. Digikey wanted 20 bucks for a delivery to Oz, I didn't bother checking at Mouser since Farnell had everything (kinda) except the resistors. I'm saying "kinda" cause I'm noticing a lot of parts are now "available in 6-7 days", meaning they are actually not in Australia. Anyway, not in a hurry, so I ordered them 2 weeks ago.

Similarly to you, I couldn't find a suitable 0.1% resistors there or anywhere else in Australia. I figured having a 681 ohm in high precision is a waste of money, since the value is off from the word go. So I ordered 30 of each resistors in plain 1% and I'll pick the matched triplets out of the pile. I'm not THAT interested in precision anyway. Main thing to me is identifying what the part is and if it is actually functioning, values.... not so much.

I'm now looking forward to firing this thing up and seeing what it does.

P.S. I also got 3 mini test clips and a bit of wire from Jaycar to be able to test components in-circuit. Again, important thing is to find out whether something is blown to avoid removing it unnecessarily and risking the board in the process. I'll 3D print the box for it, which seems to have occured to many others since there are already multiple designs available on Thingiverse.
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on July 25, 2018, 11:50:17 am
I've tried compiling the 1.33m firmware with WinAVR, and I got an error in a file I haven't touched. Any ideas?

ST7735.c: In function 'LCD_CharPos':
ST7735.c:341: error: expected expression before ';' token
ST7735.c: In function 'LCD_ClearLine':
ST7735.c:417: error: expected expression before ')' token
ST7735.c:419: error: expected expression before ')' token
ST7735.c:421: error: expected expression before ')' token
make.exe: *** [ST7735.o] Error 1

> Process Exit Code: 2
> Time Taken: 00:07

Edit: Never mind, I figured it out. In file "Config_328.h" one of the LCD display definitions is already uncommented. I uncommented the correct one as per file "clones", which made the compiler spit the dummy, cause 2 displays at once. Makes sense :) Result:

AVR Memory Usage
----------------
Device: atmega328

Program:   32392 bytes (98.9% Full)
(.text + .data + .bootloader)
Data:        241 bytes (11.8% Full)
(.data + .bss + .noinit)
EEPROM:      852 bytes (83.2% Full)
(.eeprom)
Title: Re: $20 LCR ESR Transistor checker project
Post by: BradC on July 25, 2018, 02:23:07 pm

Similarly to you, I couldn't find a suitable 0.1% resistors there or anywhere else in Australia. I figured having a 681 ohm in high precision is a waste of money, since the value is off from the word go.

I went 681 & 475k 0.1% (from Digikey) and just changed the constants in the source to tweak it up. I thought as long as the matches between channels were close the absolute value wasn't so important.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on July 25, 2018, 02:44:07 pm
P.S. I also got 3 mini test clips and a bit of wire from Jaycar to be able to test components in-circuit. Again, important thing is to find out whether something is blown to avoid removing it unnecessarily and risking the board in the process.

You cannot reliably test components in circuit with this tester.  An in circuit tester uses a different method to be able to test components in circuit.

As long as there is no residual charge in any of the components you shouldn't damage the tester, you will just get incorrect readings.  Components will appear to be something they are not, have incorrect values or appear shorted depending on the other components around the part you are testing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 25, 2018, 04:15:41 pm
Regarding the 0.1% resistors, inside the EU you can them in single quantities for €0.29-0.35 (Yageo TH) or €0.25 (Panasonic SMD) from reichelt.de.
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on July 25, 2018, 07:57:42 pm
You cannot reliably test components in circuit with this tester.  An in circuit tester uses a different method to be able to test components in circuit.

As long as there is no residual charge in any of the components you shouldn't damage the tester, you will just get incorrect readings.  Components will appear to be something they are not, have incorrect values or appear shorted depending on the other components around the part you are testing.

I realize that, I'm just hoping for go/no-go for components to speed up the diagnosis of faulty circuits. So you're saying even that wouldn't work?

Regarding the 0.1% resistors, inside the EU you can them in single quantities for €0.29-0.35 (Yageo TH) or €0.25 (Panasonic SMD) from reichelt.de.

I didn't look any more into the precision resistors, as what was available here in Australia were not specified values. 681 ohms and 475k weren't exactly what was specified. While playing with WinAVR I've realized that these values can be specified in software what they actually are, and that I could have used different values and declared them in software accordingly. I haven't seen that bit of info mentioned anywhere in this thread, and it would have been useful in the "replacement parts ordering" phase :) Maybe something to add to the documentation?

Again, utmost measurement accuracy isn't that important to me, but it may be to others.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 25, 2018, 10:11:15 pm
You cannot reliably test components in circuit with this tester.  An in circuit tester uses a different method to be able to test components in circuit.

As long as there is no residual charge in any of the components you shouldn't damage the tester, you will just get incorrect readings.  Components will appear to be something they are not, have incorrect values or appear shorted depending on the other components around the part you are testing.

I realize that, I'm just hoping for go/no-go for components to speed up the diagnosis of faulty circuits. So you're saying even that wouldn't work?

It depends how badly you misinterpret the circuit layout. Take for example a go/no-go on some filter caps. You measure one, in circuit, and the capacitance seems to match the rating on the side and the ESR looks low. So, that might look like it's an OK cap. However, there are several in parallel on the board, which means the capacitance is less than it should be and the ESR is higher than it appears.

That's a simple example that usually isn't hard to detect by examining the PCB traces. But not every case is necessarily like that, especially if the junction of active components turn on during the measurement. So, if you know how the circuit works, you may be able to make some interpretations. If not, then what you see may not be what you get.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MasGanBro on July 26, 2018, 02:17:23 pm
The two '?'s indicate that the FET's drain and source couldn't be detected, i.e. drain and source are likely to be symmetrical. The m-firmware displays an 'x' instead of the '?'.

Ah, thanks for info. I thought that a fake J201.

Again (peace for ask too much), some question
- the batt is around 8.7x V, but in lcr-t4 always show around 7.0x V
really too much drop. That normal?

- if ditch battery, use 9-12V adaptor, what polarity? Center negative or positive?

- what the latest tester can handle all feature/function?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on July 26, 2018, 03:11:58 pm
I'm not sure about battery voltage thing, it could be a setting in firmware or hardware problem/wrong component. Look at the circuit and check components along the power supply lines.

For external power jack - center=positive (standard)

From what I understand, the best Chinese clone is the one marked "AY-AT" on the board. That's what I actually bought, except when it arrived, there were no such markings on the board. It does look the same, and it worked straight up after I soldered everything. So a copy of a copy, but so far seems ok.

I'm planing to use 1.33m or trendy-1.26m firmware. Not sure what's the difference (maybe Marcus will tell us). From what I worked out, you can choose features you want when you are compiling your own firmware, within reason and within the constraints of memory size.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 26, 2018, 05:49:28 pm
Again (peace for ask too much), some question
- the batt is around 8.7x V, but in lcr-t4 always show around 7.0x V
really too much drop. That normal?

Maybe the resistors of the voltage divider for battery monitoring have different values. Check the voltage drop across the BJT switching the power. Is there a diode for reverse polarity protection? You can adjust all values in the firmware's configuration file.

- what the latest tester can handle all feature/function?

DIY ;) There's no clone with all hardware options on board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 26, 2018, 05:58:50 pm
I'm planing to use 1.33m or trendy-1.26m firmware. Not sure what's the difference (maybe Marcus will tell us). From what I worked out, you can choose features you want when you are compiling your own firmware, within reason and within the constraints of memory size.

For a while there were two branches of the m-firmware, one for the classic HD44780 text display (classic) and another one for graphic displays (trendy). This was necessary to support the ATmega 168 with just 16kB flash. After dropping the support for the 168 the two branches were joined together. So the latest and greatest version is 1.33m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on July 27, 2018, 12:04:11 am
For any of  you thinking you can test capacitors in circuit, the answer is yes and no.

Check out this video where the person explains it quite well: https://www.youtube.com/watch?v=fD-8Dppp03w (https://www.youtube.com/watch?v=fD-8Dppp03w)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on July 28, 2018, 08:29:13 am
For any of  you thinking you can test capacitors in circuit, the answer is yes and no.

Just to be clear they are ESR meters.  Their component tester is not recommended or able to reliably detect in circuit components and it does not tolerate charged capacitors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MattP79 on July 29, 2018, 02:30:15 pm
Forgive my ignorance, I'm a little ??? by the options available to me.  I have one of the AY-AT clones running software version 1.12K which I'd like to update.  Having looked at the options for programming an ATMega328 chip, on AliExpress I've found this: ATMEGA16 ATmega32 Board + USBISP 3.3V / 5V AVR Download Programmer New (https://www.aliexpress.com/item/J34-1Set-ISP-ATMEGA16-ATmega32-Board-USBISP-3-3V-5V-AVR-Download-Programmer-New/32601434599.html) with identical options available on eBay et al... Is this a sensible option for someone who has limited experience with such devices?  Would an Arduino Uno R3, which is a similar cost, be a better option?  Money is limited hence looking at these limited options.

Many thanks in advance :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 29, 2018, 02:56:28 pm
A simple ISP programmer for 2 bucks is sufficient, and a search for "AVR programmer" will list tons of those. You might need to build an adapter from 10 pin to 6 pin if the programmer doesn't include one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on July 29, 2018, 07:22:28 pm
I have one of the AY-AT clones running software version 1.12K which I'd like to update.

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MattP79 on July 29, 2018, 08:16:40 pm
Thanks :)  So - yes - exactly that.

I am reading the thread from page 1 but hadn't make it that far yet.  Who'd have kids who need almost constant attention? |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 31, 2018, 02:27:53 am
Kudos for attempting to read the entire thread from the beginning. You are one of the few willing to be so diligent. Many don't make it further than a page or two when starting from the end of the thread. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on July 31, 2018, 05:11:20 am
Many don't make it further than a page or two
Most don't even bother trying that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MattP79 on August 03, 2018, 09:20:37 pm
Thanks for the thread! Finally read myself back to this page and now I'm a little lost what to do. Like when you finish binge watching a good TV series.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 03, 2018, 09:49:32 pm
Buy an inexpensive Uno and some 328 ICs. Use the Uno to program the firmware you want onto the new ICs. Then, swap the 328 chips. If something goes wrong, you don't like the new firmware, or you want to compare behaviors, just put back the original 328 containing version 1.12k.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on August 04, 2018, 04:22:52 am
I'm a little lost what to do.

Well, it's component tester. You buy it, and then you measure components with it. If you're feeling saucy, you update the program (there are two flavours). If that doesn't help, then you'll have to be more specific.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 04, 2018, 04:26:38 am
You can see Matt's original question in this post: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1708790/#msg1708790 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1708790/#msg1708790)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on August 04, 2018, 05:48:57 am
The question was answered. He was given a link to a $2 programmer and flashing instructions.

If some part of that was unclear, then he needs to specify. If he has new questions, he still needs to specify. I don't know about you, but I can't read minds.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vague on August 05, 2018, 11:40:08 am
Thank you Madires and HK for all the time and effort that you have put into this project.
Can you use a a 20MHz XTAL with the 1.13k firmware or are you limited to 16MHz?
Than you
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 05, 2018, 02:02:31 pm
Karl-Heinz has started adding support for 20MHz but I don't know if the current trunk version includes full support already.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on August 05, 2018, 08:19:21 pm
I've noted that the tester using Karl-Heinz firmware reports a maximum "worst case" ESR of .14K (or 140)
Is this what others see too? (Same behavior on two meters, just curious what others get...)
Also in the attached example a Fluke 28-II can't even get a capacitance reading, yet the value reported is correct for the cap: Lelon REA 100µF 50v
I know the cap is dead because replacing it made the equipment it was in come back to life ;)

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 06, 2018, 07:32:07 am
Karl-Heinz has started adding support for 20MHz but I don't know if the current trunk version includes full support already.

Yes,current trunk version Karl-Heinz  includes full support 20Mhz  :D

I've noted that the tester using Karl-Heinz firmware reports a maximum "worst case" ESR of .14K (or 140)
Yes,I have same results. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 06, 2018, 02:45:13 pm
Also in the attached example a Fluke 28-II can't even get a capacitance reading, yet the value reported is correct for the cap: Lelon REA 100µF 50v
I know the cap is dead because replacing it made the equipment it was in come back to life ;)

A high Vloss value indicates a leaky cap. Vloss is simply the self-discharge rate and the capacitance measurement is able to compensate this to some extend. So the capacitance can be ok but the resistive part of the cap causes Vloss to increase. Or in other words, the firmware is aware of C and Rp (cap's equivalent circuit).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on August 06, 2018, 04:00:10 pm
Yes, I was implying that I am quite impressed by what the little meter can do :)
Can I ask when you wrote this over here (https://www.eevblog.com/forum/testgear/mr-carlsons-lv-capacitor-leakage-tester!-it's-finally-out!/msg1500706/#msg1500706), quoted below too, in relation to Mr. Carlsons LV Leakage tester.
How would that be different vs the leakage value in percentage we see now, I do realize you write the M-firmware, and I have the K-firmware.

Quote
"The k-firmware derives a value called V_loss (in %) which indicates the self-discharge rate of an electrolytic cap. The m-firmware does something similar but displays an equivalent leakage current. We could add a leakage check which charges up the capacitor and measures the voltage drop across a current shunt. The lower limit would be a about 2nA (Vcc is 5V). I'll put the idea on my to-do list."
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 06, 2018, 08:12:00 pm
The current Vloss or I_l values are a side product of the capacitance measurement. The method mentioned in the thread about Mr. Carlson's LV leakage tester would be a another approach allowing to measure the leakage current directly while possibly supporting lower currents.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on August 06, 2018, 09:30:45 pm
That sounds great, did you do any work on it or the idea is on hold?
Title: Re: $20 LCR ESR Transistor checker project
Post by: kikook on August 07, 2018, 07:30:22 am
Hi,
Trying to compile the Markus firmware with winavr.
I'm having this error, someone can say me what i'm doing wrong ?
Thanks.



Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 07, 2018, 10:28:56 am
That sounds great, did you do any work on it or the idea is on hold?

It's still on my to-do list. At the moment I'm working on a different project.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 07, 2018, 10:34:28 am
Trying to compile the Markus firmware with winavr.
I'm having this error, someone can say me what i'm doing wrong ?

I don't use winavr but this seems to be some internal problem. Maybe a bad path?
Title: Re: $20 LCR ESR Transistor checker project
Post by: neslekkim on August 07, 2018, 11:38:36 am
Looks like 644 based devices starts popping up now: https://www.ebay.com/itm/113001217497 (https://www.ebay.com/itm/113001217497)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on August 07, 2018, 11:46:07 am
Banggood has this M644 for 24.98 usd https://www.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html? (https://www.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html?)
Title: Re: $20 LCR ESR Transistor checker project
Post by: kikook on August 07, 2018, 11:50:47 am
Thanks Markus,
It's curious because I don't have any problem to compile Karl-Heinz's firmwares.
Trying re-install winavr without any success.


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 07, 2018, 02:52:07 pm
It's curious because I don't have any problem to compile Karl-Heinz's firmwares.
Trying re-install winavr without any success.

When winavr compiles the k-firmware without any problems then there has to be another reason. I remember a special #define which we had to add for one IDE. Maybe it's something like that. Can someone using winavr help with this issue?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 07, 2018, 03:01:46 pm
Looks like 644 based devices starts popping up now: https://www.ebay.com/itm/113001217497 (https://www.ebay.com/itm/113001217497)

Nice! This one includes the extended frequency counter option with the low and high frequency oscillators for testing crystals and a prescaler (or some variant of it).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on August 07, 2018, 03:07:16 pm
Odd question: Is the company name "Original Hiland"? (or do they claim all stolen idea's are "original"?)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 07, 2018, 03:07:26 pm
Banggood has this M644 for 24.98 usd https://www.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html? (https://www.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html?)

"Original Hiland M644 Transistor Tester" ::) More likely "genuine clone". :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 07, 2018, 03:19:07 pm
Odd question: Is the company name "Original Hiland"? (or do they claim all stolen idea's are "original"?)

It's the clash between our concept of copyright and Chinese culture. If I got this right, the copying of a original design or a piece of art is some kind of honoring the inventor/artist while cheating buyers at the same time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on August 07, 2018, 03:24:37 pm
Banggood has this M644 for 24.98 usd https://www.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html? (https://www.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html?)

They must love me!!! Looks like the new M644 version use the same case of my current tester and apparently they even copyed my solution to mount the ZIF socket in the case!!! Great  :-+
I must have it!! Looking forward for the new improvement available with the bigger microcontroller  :popcorn:

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on August 07, 2018, 04:15:48 pm
It's curious because I don't have any problem to compile Karl-Heinz's firmwares.
Trying re-install winavr without any success.

When winavr compiles the k-firmware without any problems then there has to be another reason. I remember a special #define which we had to add for one IDE. Maybe it's something like that. Can someone using winavr help with this issue?

Hi.

If it fails you can try to compile with my WinAVR:

http://www.mediafire.com/file/45ybva33chnak9g/WinAVR-20100110.rar (http://www.mediafire.com/file/45ybva33chnak9g/WinAVR-20100110.rar)

Just replace your WinAVR folder with the downloaded one.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on August 07, 2018, 06:08:19 pm
For some reason you need the right version of WiAvr, specially in windows 10. This has been discussed a few times in this thread.  :-//

The wrong version will give you code too big to fit on the microcontroller. Follow Pepe's link and also install Cygwin 64.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 08, 2018, 02:26:19 am
Looks like 644 based devices starts popping up now: https://www.ebay.com/itm/113001217497 (https://www.ebay.com/itm/113001217497)

Nice! This one includes the extended frequency counter option with the low and high frequency oscillators for testing crystals and a prescaler (or some variant of it).

Oh, interesting. And the ZIF socket is socketed.

They must love me!!! Looks like the new M644 version use the same case of my current tester and apparently they even copyed my solution to mount the ZIF socket in the case!!! Great  :-+
I must have it!! Looking forward for the new improvement available with the bigger microcontroller 

I guess so. Hmm, does this mean that if you come up with an idea, you should post it all over the net? That way, if China copies and manufactures it, you can buy it for less money and effort than if you made it yourself? :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on August 08, 2018, 06:37:50 am
Looks like 644 based devices starts popping up now: https://www.ebay.com/itm/113001217497 (https://www.ebay.com/itm/113001217497)

Nice! This one includes the extended frequency counter option with the low and high frequency oscillators for testing crystals and a prescaler (or some variant of it).
This M644 seems to be the same one unless I'm mistaken? And at prices rivaling some M328 designs! Hell I'll order one right away, $17.70 including shipping can't be beat!
https://www.ebay.com/itm/253794953057 (https://www.ebay.com/itm/253794953057)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on August 08, 2018, 07:28:02 am
I guess so. Hmm, does this mean that if you come up with an idea, you should post it all over the net? That way, if China copies and manufactures it, you can buy it for less money and effort than if you made it yourself? :-DD

That's the plan  >:D. I know I don't have that power, but all this small tools manufacturers are paing attention on what is posted all over the interweb so here are my suggestions:

Dear clones manufacturer, please consider to add a companion case for this tester with an exposed smd test area like the ESR02PRO or provide an smd accessory, LiPo battery, microusb port for external power, recharge the battery and usb serial interface.

While you're at it, please combine the two firmware variants m and k and provide an open souce Marcus-Heinz GitHub repository.
Thank you  :popcorn:

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 08, 2018, 07:42:06 am
I like it. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: garthk on August 08, 2018, 10:28:19 am
Haven't seen anyone mention it yet, so I'm just going to mark 200 pages of posts, here. Onya!
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on August 08, 2018, 12:10:03 pm
Yeah geat achivement for a small but usefull device...
The issue is that 180 pages are just for "How can I upgrade the firmware" or "I blew up my tester with a charged capacitor..."

It should be nice if it was possible to sort the topic by "most thanked post", or "most quoted message in the the topic" .....

Someone knows if it is possible to apply some filters like this in the advanced search?

This could be a simple way to extract a FAQ from 200 pages  :)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: BradC on August 08, 2018, 12:49:57 pm
Haven't seen anyone mention it yet, so I'm just going to mark 200 pages of posts, here. Onya!

It's only 100 here, but yeah it is still an impressive tally.

I recently built a new one and upgraded an old one with a 20mhz crystal, decent regulators and real 0.1% resistors rather than the cheap grunge it came with. To be honest the improvement in tolerance and accuracy was not really noticeable for what I use it for.

The biggest improvement I've seen with these units is the faster crystal combined with the latest m firmware.

Seriously impressive little machines, but they don't seem to like 400uF at 400V.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 08, 2018, 03:31:07 pm
Seriously impressive little machines, but they don't seem to like 400uF at 400V.

That would give you a good bang for the buck >:D
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 08, 2018, 06:20:12 pm
Yeah, if you forgot to discharge it. :o
Title: Re: $20 LCR ESR Transistor checker project
Post by: BradC on August 09, 2018, 12:41:00 am
Yeah, if you forgot to discharge it. :o

Resulting in "holy atmega batman". Thankfully no other damage and it prompted me to wire up a programming header and start the improvement process. Cost : one atmega, Education value  : priceless.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on August 09, 2018, 08:33:17 pm

[/quote]

Oh, interesting. And the ZIF socket is socketed.


[/quote]

Where can I buy such socket for ZIF socket?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 10, 2018, 03:11:39 am
It's a DIP IC socket. Choose one with the matching number of pins.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on August 10, 2018, 09:47:04 am
I have used this.
Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on August 12, 2018, 01:55:23 am
Where can I buy such socket for ZIF socket?

You can buy quality ones form element14 and other brand name suppliers, otherwise you can get cheap ones from ebay.  Just search for "ZIF socket".

For a socket for the ZIF, same suppliers just search for "DIL socket".  You can just buy a normal socket the same size to use as the socket for the ZIF, or use 0.1" pin strips.  Be careful about using machines sockets as some ZIF pins do not fit into them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 12, 2018, 09:46:17 am
Whats people thoughts on these testers
https://www.ebay.co.uk/itm/Transistor-Tester-TFT-Diode-Triode-Capacitance-Meter-LCR-TC1-ESR-NPN-PNP-MOSFET/123243495651?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D52945%26meid%3Ddc158dbd5ed6422f97eeabca7510c15f%26pid%3D100005%26rk%3D6%26rkt%3D12%26sd%3D222991613357%26itm%3D123243495651&_trksid=p2047675.c100005.m1851 (https://www.ebay.co.uk/itm/Transistor-Tester-TFT-Diode-Triode-Capacitance-Meter-LCR-TC1-ESR-NPN-PNP-MOSFET/123243495651?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D52945%26meid%3Ddc158dbd5ed6422f97eeabca7510c15f%26pid%3D100005%26rk%3D6%26rkt%3D12%26sd%3D222991613357%26itm%3D123243495651&_trksid=p2047675.c100005.m1851)
https://www.youtube.com/watch?v=xvHW9zVjC3E (https://www.youtube.com/watch?v=xvHW9zVjC3E)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 12, 2018, 04:58:56 pm
One major drawback of the TC1 is the additional MCU which controls power and the test button. That design is incompatible with the standard one and prevents firmware upgrades (k/m firmware). A while ago I released a simple circuit for replacing the control MCU to remove the incompatibility. Of course this will render the TC1's modified firmware useless. There could be another big problem with the design of power supply which I still have to investigate. My TC1's Vcc jumps around wildly, especially when it runs longer than a few seconds. Also the boost converter gets hot. Could be a bad component or bad design. The current draw seems a tad low compared to values others have reported. A common issue with the TC1 is a shorted cap in the power supply circuitry (backlight lit, but no display).
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 12, 2018, 05:28:36 pm
thanks for the reply it just seemed a good price now i know why.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on August 13, 2018, 08:11:09 pm
is the t7 any better?
https://www.ebay.co.uk/itm/UK-Universal-LCR-T7-ESR-Diode-Triode-Capacitance-Mos-Transistor-Tester-CASE/123288444717?hash=item1cb4905f2d%3Ag%3AdEsAAOSw8lhbZAU7&_sacat=0&_nkw=LCR+T7&_from=R40&rt=nc&_trksid=m570.l1313 (https://www.ebay.co.uk/itm/UK-Universal-LCR-T7-ESR-Diode-Triode-Capacitance-Mos-Transistor-Tester-CASE/123288444717?hash=item1cb4905f2d%3Ag%3AdEsAAOSw8lhbZAU7&_sacat=0&_nkw=LCR+T7&_from=R40&rt=nc&_trksid=m570.l1313)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on August 14, 2018, 01:15:41 am
is the t7 any better?

Others may have more info, but I think it is basically the same inside as the LCR TC1.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 14, 2018, 10:23:44 am
Yep, it's the same PCB with a different display module (dual row pin header at the right).

EDIT:
Update on my TC1's power supply issue. The problem was caused by the MLCC filter caps of the Zener test voltage. They were partly leaky and at some temperature they became even more leaky causing Vcc dips. It seems that C11 & C12 should be replaced with 0805 X7R 4.7µF 50V types from a reputable vendor anyway (haven't seen 100V for this type).
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 14, 2018, 08:56:44 pm
Hmm, I wonder if those MLCC were fractured inside.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 15, 2018, 07:28:41 am
It seems that C11 & C12 should be replaced with 0805 X7R 4.7µF 50V types from a reputable vendor anyway (haven't seen 100V for this type).
Madires, http://www.farnell.com/datasheets/608985.pdf (http://www.farnell.com/datasheets/608985.pdf)   ? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 15, 2018, 01:35:48 pm
Digikey's parametric search lists 0805 4.7µF MLCCs just up to 50V. And because the boost converter runs at 1MHz I'd prefer MLCCs over low-ESR TH electrolytics which are available for much higher voltages.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on August 15, 2018, 02:09:02 pm
the originals may only be rated at 25v or less, they may have used the same series they would for general logic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on August 15, 2018, 03:28:02 pm
An 0805 50V 4.7uF cap will probably have around 0.1uF capacitance at 50V...
Title: Re: $20 LCR ESR Transistor checker project
Post by: LatropEmit on August 15, 2018, 03:51:47 pm
Hey everyone
I need some help with my tester. I tried to update the firmware with the mega644_LCD2004 k-firmware, but now when I try to power on the tester the LCD came on showing nothing and when I release the rotary it power of instantly.
I tried to read and search here and I know I have seen the answer somewhere but I can't remember where..

So my tester is the new one mentioned a few post ahead the Hiland M644.
I attached pictures from the display and the platine itself maybe it is easier to help with this pictures.

First I tried to flash the precopiled hex and eep then I tried to recompile it from scratch and setting in the make file some options like the right Part-No ect.
But I don't know what I have to set for the LCD.
To be honest I even don't  know if it's the right firmware to flash.. XD

Then setting the right fuses it's a other thing...
I tried with L 0xFF, H 0xD9 and E 0xFC then i tried with L 0x62, H 0xD9 and E 0xFC

But like you see not working, so now I am here to ask help :)

Ah if it helps originally it was a 1.12k fw on it..(https://uploads.tapatalk-cdn.com/20180815/4f0dd30f1fa239a0617028e51e4a3032.jpg)(https://uploads.tapatalk-cdn.com/20180815/a82d1242191c11206b2510e18d134b71.jpg)

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Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 15, 2018, 04:17:57 pm
Digikey's parametric search lists 0805 4.7µF MLCCs just up to 50V. And because the boost converter runs at 1MHz I'd prefer MLCCs over low-ESR TH electrolytics which are available for much higher voltages.
AVX 4.7μF Multilayer Ceramic Capacitor MLCC 100V dc ±20% X7S Dielectric 1206 (3216M) SMD, Max. Temp. +125°C
I think that this model of the capacitor without problems will be suitable for replacement of C11-C12.
The place on the printed circuit board allows to make it.


Ah if it helps originally it was a 1.12k fw on it..

Did you try to read this original firmware (1.12k) or it is blocked for reading?
It is necessary to make the drawing of the schematic diagram in order that it is easier to understand as the display is connected to the ATMega644 processor!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 15, 2018, 05:27:21 pm
An 0805 50V 4.7uF cap will probably have around 0.1uF capacitance at 50V...

Yep, the DC bias derating. So it's a low-ESR electrolytic again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: LatropEmit on August 15, 2018, 06:51:57 pm
Yeah I had read the fw and I think I had it dumped properly but I got it overwritten afterwards... I thought I saved the fw in a secure place but in my rush I forgot do to so :(

Hmm... ok shame on me, when I let everything hooked up on my breadboard then i get this problem with the LCD shutting down after releasing ^^

If I try to power on the tester when everything is disconnected it powers on remains on but display is showing nothing..

I attached another picture with the back site of the pcb. First thing that I notice is that LCD and SPI are sharing some pins...

Ok found out display is a JLX12864G-378 V2.0 
Now I have to find out how configuring the make file...

(https://uploads.tapatalk-cdn.com/20180815/9a313ce7f72e5617d95fe294217d4c55.jpg)

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Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 16, 2018, 06:51:41 am
Ok found out display is a JLX12864G-378 V2.0
Now I have to find out how configuring the make file...
In the photo it isn't really well visible to what ports of the processor the display is connected! Can you make such table of connection of LCD to ATMega644 ports?
For example:
LCD (D6) - pin ATMega644?
LCD (D7) - pin ATMega644?
LCD (CS) - ?
LCD (RST) - pin ATMega644?
LCD (RS) -  pin ATMega644?
Title: Re: $20 LCR ESR Transistor checker project
Post by: LatropEmit on August 16, 2018, 06:03:16 pm
Ok so I tried to trace back everything but i have some problems with VSS and CS they are connected to GND and maybe PA3...
I made a photos from the front and back site of the board. Then I overlapped both and tried to trace back..

So in sostans I have found

LCD        ATMEGA644

LEDA  -   VCC
VSS     -   GND (PA3)
VDD    -   VCC
RS      -    PB5
RST    -    RESET
CS      -    GND(PA3)
D7      -    PB7
D6     -     PB6

Like I said I have problems with VSS and CS but I attached the picture that I made with the trace lines. Black lines are on the backside of the pcb blue on the front hope I got I right ^^(https://uploads.tapatalk-cdn.com/20180816/632d854817d955c6eba4cf58b60bd280.jpg)

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Title: Re: $20 LCR ESR Transistor checker project
Post by: Discotech on August 17, 2018, 02:36:53 pm
How low can the GM328 version read caps ?

Trying to measure some 3pF ceramic caps and it doesn't recognise them  :o
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 17, 2018, 02:45:05 pm
k-firmware: 25pF
m-firmware: 5pF

solution:
- take a cap with a known value, e.g. 33pF, and connect it in parallel with the cap to check
- subtract capacitance of known cap

The "Sampling ADC" of the k-firmware might also work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Discotech on August 17, 2018, 02:49:50 pm
k-firmware: 25pF
m-firmware: 5pF

solution:
- take a cap with a known value, e.g. 33pF, and connect it in parallel with the cap to check
- subtract capacitance of known cap

The "Sampling ADC" of the k-firmware might also work.

I've found another solution of putting in a higher rated cap it can detect, removing it so cap value resets to 0 then place small cap and it will show value

Seems strange it can detect value but only if test is already active ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 17, 2018, 04:24:33 pm
LCD        ATMEGA644
LEDA  -   VCC
VSS     -   GND (PA3)
VDD    -   VCC
RS      -    PB5
RST    -    RESET
CS      -    GND(PA3)
D7      -    PB7
D6     -     PB6
The schematic of this clone almost completely corresponds to the schematic diagram from a manual of Karl-Heinz Kübbeler (March 8, 2018) on page 33 (figure 2.26) except for some details and the used display on ST7565.
Load a test firmware which I have collected. Everything has to work normally. I have checked this firmware in Proteus.
Fuse establish such LOW-F7, HIGH-D9, EXT-FC
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 17, 2018, 04:25:18 pm
Actually that would be a bug. Hmm. There's another possibility. If the capacitance zero offset (determined during the self-adjustment) is larger than 25pF (k-firmware) it should also work. In this case the tester's own capacitance is large enough to work as a known cap in parallel.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 17, 2018, 04:32:45 pm
I've found another solution of putting in a higher rated cap it can detect, removing it so cap value resets to 0 then place small cap and it will show value
Seems strange it can detect value but only if test is already active ?
It is feature of work of k-firmware in the cycle mode.For the test of "small" capacities at first on test pins 1-3 in the mode of a cycle we measure any capacity above 25pf, then without pressing the Test button we connect on the same pins "small" value capacitor from 1pf. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: LatropEmit on August 17, 2018, 05:03:57 pm
LCD        ATMEGA644
LEDA  -   VCC
VSS     -   GND (PA3)
VDD    -   VCC
RS      -    PB5
RST    -    RESET
CS      -    GND(PA3)
D7      -    PB7
D6     -     PB6
The schematic of this clone almost completely corresponds to the schematic diagram from a manual of Karl-Heinz Kübbeler (March 8, 2018) on page 33 (figure 2.26) except for some details and the used display on ST7565.
Load a test firmware which I have collected. Everything has to work normally. I have checked this firmware in Proteus.
Fuse establish such LOW-F7, HIGH-D9, EXT-FC
Soooo after checking the pins and re read the make file, and checked the config.h to see what pins are used, I realised that I have made a really big mistake....   
I didn't know what LCD controller to use in the make file..
Like I wrote it is a ST7565  so stupid me had in the make file WITH_LCD_ST7565 = 1306 AND NOT 1...
Therefore i compiled everything with the wrong settings...
Now after a quick test i got everything up and running... adjusting h-flip and now it's running without problems...

So in substance It works like a charme no extra fancy rewrite only setting everything right in the make file....

But thank you for taking the time to helping me :)

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Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 17, 2018, 05:47:16 pm
It is feature of work of k-firmware in the cycle mode.For the test of "small" capacities at first on test pins 1-3 in the mode of a cycle we measure any capacity above 25pf, then without pressing the Test button we connect on the same pins "small" value capacitor from 1pf. :)

Thanks for the explanation! I've missed that feature.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Discotech on August 17, 2018, 08:55:22 pm
I've found another solution of putting in a higher rated cap it can detect, removing it so cap value resets to 0 then place small cap and it will show value
Seems strange it can detect value but only if test is already active ?
It is feature of work of k-firmware in the cycle mode.For the test of "small" capacities at first on test pins 1-3 in the mode of a cycle we measure any capacity above 25pf, then without pressing the Test button we connect on the same pins "small" value capacitor from 1pf. :)

On further messing around I've found if you go through the menu and specifically choose to measure capacitor it allows small value caps to be tested without using a higher value

Seems strange that you can't just put in cap, then turn on the tester to test automatically and instead have to go through menu first to do it for low values, I'm not sure I'd call it a feature as it feels more a hindrance  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 18, 2018, 07:29:38 am
Did you attentively read a manual from Karl-Heinz?He has explained everything concerning measurements of small capacitors in the automatic mode! :)
"23.Capacitors with value below 25pF are usually not detectet, but can be measured together with
a parallel diode or a parallel capacitor with at least 25pF. In this case you must subtract the
capacity value of the parallel connected part. For processors with at least 32K flash memory
the tester changeover to a special capacity meter function, if a capacitor with more than 25pF
is once measured at TP1 and TP3. In this capacitor meter mode you can measure capacitors
below 25pF at TP1 and TP3 directly."
"In the same way the tester changes to a capacity
meter function, if a capacitor is detected at TP1 and TP3. This operation mode is indicated
with a [C] at the right side of the first display line. With this capacity meter function capacity
values are shown down to 1pF. Only for the automatic start you need a capacitor with more
than 25pF. Both special modes can be finished by a key press. The tester will then continue
with the normal tester function."

For menu function "Capacitor meter 1-3":
"Capacitor meter with the 1-3 symbol the tester changes to a capacitor meter function at TP1
and TP3. This operation mode will be marked with a [C] at the right side of the first display
line. With this operation mode capacitors from 1pF up to 100mF can be measured. In this
operation mode the measurement is repeated without key press. With a key press the tester
finish this operation mode and returns to the menu. In the same way as with resistors, the
tester changes automatically to the capacitor meter function, if a capacitor between TP1 and
TP3 is measured with the normal tester function. After a automatically start of the capacitor
meter function the tester returns with a key press to the normal tester function."

Title: Re: $20 LCR ESR Transistor checker project
Post by: nakcho on August 19, 2018, 08:04:19 pm

good morning I have a problem that more than 6 months ago I can not

fix it hehe I have no experience with programming ... I tell you my little problem ... buy a transistor tester M328KIT   https://www.ebay.com/itm/GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM-Signal-Generator-DIY/152443029396?epid=577875436&hash=item237e500794:g:l3wAAOSw4A5YqU1i (https://www.ebay.com/itm/GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM-Signal-Generator-DIY/152443029396?epid=577875436&hash=item237e500794:g:l3wAAOSw4A5YqU1i)   
the original firmware version was 1.12K the problem is that I stopped working ... from one day to another did not want turn on only white screen and off ... well here comes my next step .. eh recorded again the firmware that I downloaded from this web and the problem persists on white screen with some firmware and others take to appear something like that is slow. and lately I found a firmware version 1.12k and 1.13k 1.33m turns on as fast as I should and starts asking me to make the short circuit with the 3 points 1 - 2 - 3 I do it ... but it does not do anything ... it keeps showing me the short-circuit message ... after a few minutes (1 to 2 mi nutos) keeps doing a test I guess ... until you get to ask me to put a capacitor of 100NF I guess that ... because it shows that on the screen ... when putting the capacitor ... it stays there branded and there it does not come out ... that same problem happens to me with 3 or 4 firmware that seems to work fine but in the end it remains if the rest of the effect shows white screen or it takes too long to show something on the screen ... can someone help me to put the firmware again to this version (I have not modified anything the device is as I buy it ... I'm only interested in uploading the firmware again and it works as before ..) please .... I need a little help

my English is terrible ... I hope you understand me something
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on August 20, 2018, 08:56:54 am
Did you already replace the cpu?
If not, I would replace it for a new one and program it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nakcho on August 20, 2018, 01:52:32 pm
Did you already replace the cpu?
If not, I would replace it for a new one and program it.

good morning ... if I actually change it because the original wine when I recorded it so many times I changed the fuse I was blocked ... well now I bought 2 more cpu for tests and the same happens with both .. in the original also the same thing happened to me ... record the cpu with this file https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=445891 1.13 that they simulated the proteus and it starts everything well in its time ... the only thing is that it does not detect anything .. when wanting to program something ... and if I do selft test it does not detect the short circuit ... ... which would have to install and configuration of the fuse ... although I'm already ... tested with this line with all the firmware .. please can someone give me a hand I'm only interested in recovering the tester
avrdude -c usbasp -p m328p -B 0.5 -e -U flash:w:"TransistorTesterhex":a -U eeprom:w:"TransistorTester.eep":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 20, 2018, 04:03:35 pm
nakcho,сan you make small video how the tester works with an firmware 1.13k and how you do calibration? Then it will be simpler to us to solve this problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nakcho on August 21, 2018, 03:28:56 am
nakcho,сan you make small video how the tester works with an firmware 1.13k and how you do calibration? Then it will be simpler to us to solve this problem.
good indman ... I've made a video from the start of the tester to the 100nf capacitor check. as to start does not detect any component ... then perform the calibration that asks me to make a short circuit ... in the three points 1-2-3 ... since a few minutes goes to the next step that the truth is not what does it do but it throws some data to me ... then it asks me to put a capacitor of 100NF that when putting it the truth that it does not do anything it remains enough time ... and it returns to be restarted but without any successful message ... and we continue without recognizing no data
I tested firmware 1.13 that was simulated in proteus ... is the best start ... if you delay as it did in its previous version 1.12k but with its problems of recognizing the components
here I attach the link from where I pulled version 1.13k that I do not know if it would be ok ... well ... I hope you can give me a little hand ... I thank you
here the link 1.13k
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/4825/
here a demonstration video
https://www.youtube.com/watch?v=-BvXDTkKGJ0 (https://www.youtube.com/watch?v=-BvXDTkKGJ0)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 21, 2018, 08:09:26 am
Ok! I have several versions of the solution of this problem:
1. Use the original version of an firmware 1.13k Rev.798 Karl-Heinz which I have attached below.
2. If you have a reliable multimeter(DMM), then define precisely what voltage of Vcc  stabilizer 7550 exit? I see on video what on the display is shown 5.13v. If it correctly, it exceeds that level which is necessary for normal work of a tester. It is necessary to achieve that voltage of Vcc was close to value 5.00v. Perhaps, it will be necessary to replace 7550 with other better voltage stabilizer(MCP1702,LP2950)!
3. Accurately remove 2 elements - protective assembly of SRV-05 and a supressor of P6KE(6V8) which I have marked on a photo in the yellow color.
4. Repeat the procedure of calibration after implementation of points 1-3. I remind you that at emergence on the display of the inscription "T4 Isolation probes", it is necessary to remove short circuit of test contacts. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 21, 2018, 05:17:24 pm
The TC1 story continues. After replacing the MLCC filter caps for the Zener test voltage with a low-ESR electrolytic (higher voltage and no DC bias derating) I had still issues with the power supply. While checking voltages and other components  I've noticed that D2 (rectifier diode for the Zener test voltage) gets hot also as the MLCCs did. My guess is that D2 has a too low reverse voltage rating causing current to flow back into the flyback transfomer. So I've replaced the diode with another Schottky with a higher reverse voltage and now everything seems to work fine. Also the battery current draw dropped about 50-70mA. Don't we love cheap dodgy parts? >:D
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 21, 2018, 06:16:58 pm
Madires, at the owner of 2 identical LCR-TC1 one of device strong leakage of the accumulator was observed, charging lasted not for long, the analysis and check  have revealed breakdown of one of C2-C4 capacitors - there was resistance on the "ground" slightly more than 1 kOmh! From + 5v the serviceable tester consumes current from 24,6mA to 44mA.

I would like to return to a problem of C11-C12 and to explain what it is desirable to apply high-quality capacitors with penetrative voltage not less than 100v to. Below I will attach the photo of impulses which are developed by a chip of U5 with a frequency about 1 MHz for food of primary winding of the pulse transformer.
 Impulses voltage in this chain reach values from -17,6v to 65,6v, and their amplitude depends on accumulator voltage, the charge is higher, the amplitude is higher.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 21, 2018, 06:36:02 pm
Yep, a filter cap rated for 100V makes sense. After replacing the dodgy parts the Zener test voltage is nearly 50V DC without load (just the the voltage divider for measuring the voltage).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 23, 2018, 03:58:40 pm
Since my TC1 works fine now I've measured the total standby current for the tester including the alternative power control circuitry (compatible with k/m firmware). It's 5µA. User zappenduster noted 15µA standby current for the original design with U4 (https://www.eevblog.com/forum/testgear/tc1-lcr-meter-transistor-tester-fix/msg1622248/#msg1622248 (https://www.eevblog.com/forum/testgear/tc1-lcr-meter-transistor-tester-fix/msg1622248/#msg1622248)). Not too shabby :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on August 29, 2018, 01:49:09 pm
I'm not sure whether I want to use a (AY-AT) tester with an 8 MHz or 16 MHz crystal. Would one of these things form a tight connection while allowing the crystal to be changed? I'm afraid that the crystal would be too loose because it's not sprung like a DIP socket:

(https://uk.farnell.com/productimages/standard/en_GB/1218869-40.jpg)

Is the only advantage to double the resolution of capacitance measurements? I'm not really interested in using a colour-screen. I was planning on buying a separate ATMEGA328 so I could experiment with the custom firmwares but easily go back to the original configuration when I inevitably fail.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 29, 2018, 02:23:05 pm
I'd try the non-precision type socket terminal with the fork contact or a non-precision IC socket. The higher MCU clock frequency will improve any time based measurement (not just the capacitance) and also allows higher frequencies for PWM and square wave (and frequency counter).
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on August 29, 2018, 02:35:23 pm
Thanks but I'm not sure what you mean. Could you possibly post a Google image search of the kind of thing you're talking about? I need a socket that I can put into the space which the crystal is meant to go in.

Also do you know whether this appears to be a usable AY-AT clone? https://www.aliexpress.com/item/Multifunctional-Tester-GM328-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator/32815238753.html?spm=a2g0s.9042311.0.0.7dfe4c4d4D7a2i (https://www.aliexpress.com/item/Multifunctional-Tester-GM328-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator/32815238753.html?spm=a2g0s.9042311.0.0.7dfe4c4d4D7a2i)
I read in this thread that some people were laughing at a version with a 10K resistor near the rotary encoder and this one appears to have 10K resistors on either side of the rotary encoder. I don't know what those resistors are for or why 10K values are funny...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on August 29, 2018, 03:00:36 pm
If I remember correctly, they laughed because in that specific picture that 10 K resistor was loose.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 29, 2018, 03:13:10 pm
Thanks but I'm not sure what you mean. Could you possibly post a Google image search of the kind of thing you're talking about? I need a socket that I can put into the space which the crystal is meant to go in.

https://www.reichelt.de/10-pin-socket-terminal-strip-straight-rm-2-54-bl-1x10g-2-54-p6070.html (https://www.reichelt.de/10-pin-socket-terminal-strip-straight-rm-2-54-bl-1x10g-2-54-p6070.html)
https://www.reichelt.de/ic-socket-14-pin-double-spring-contact-gs-14-p8206.html (https://www.reichelt.de/ic-socket-14-pin-double-spring-contact-gs-14-p8206.html)

Also do you know whether this appears to be a usable AY-AT clone? https://www.aliexpress.com/item/Multifunctional-Tester-GM328-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator/32815238753.html?spm=a2g0s.9042311.0.0.7dfe4c4d4D7a2i (https://www.aliexpress.com/item/Multifunctional-Tester-GM328-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator/32815238753.html?spm=a2g0s.9042311.0.0.7dfe4c4d4D7a2i)

Yep, it's a typical AY-AT.
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on August 29, 2018, 04:04:46 pm
Thanks very much. I already have some of the first kind; I didn't realise it has springy contacts.

Incidentally, I just made a feature request for the custom firmware: https://github.com/svn2github/transistortester/issues/2 - do you know whether it is a feasible request to have an LED tester function where you can specify the current you want to test at and then the tester tells you the forward voltage needed to pass that current? Normally, it's a bit of a hassle to determine this with two multimeters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on August 30, 2018, 06:33:58 am
Would one of these things form a tight connection while allowing the crystal to be changed?

(https://uk.farnell.com/productimages/standard/en_GB/1218869-40.jpg)

I use machined pin headers to socket crystals, and they work fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2018, 10:10:09 am
Incidentally, I just made a feature request for the custom firmware: https://github.com/svn2github/transistortester/issues/2 - do you know whether it is a feasible request to have an LED tester function where you can specify the current you want to test at and then the tester tells you the forward voltage needed to pass that current? Normally, it's a bit of a hassle to determine this with two multimeters.

The repo at github is just an automatic clone of the original one at mikrocontroller.net and isn't maintained by anyone. So please post suggestions to one of the forums (mikrocontroller.net or eevblog.com) or send an email.

The tester's circuit doesn't support a variable current adjustment. Therefore it isn't possible to implement the feature you've suggested. BTW, the standard diode check provides a current of about 7mA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on August 30, 2018, 07:33:39 pm
Incidentally, I just made a feature request for the custom firmware: https://github.com/svn2github/transistortester/issues/2 - do you know whether it is a feasible request to have an LED tester function where you can specify the current you want to test at and then the tester tells you the forward voltage needed to pass that current? Normally, it's a bit of a hassle to determine this with two multimeters.

The repo at github is just an automatic clone of the original one at mikrocontroller.net and isn't maintained by anyone. So please post suggestions to one of the forums (mikrocontroller.net or eevblog.com) or send an email.

The tester's circuit doesn't support a variable current adjustment. Therefore it isn't possible to implement the feature you've suggested. BTW, the standard diode check provides a current of about 7mA.

Thanks. What if it just ramped up the voltage until the desired current was reached? Wouldn't that achieve the same thing? Is 7 mA the upper limit?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 31, 2018, 11:07:21 am
Nope, the tester uses two fixed resistor values (680\$\Omega\$ and 470k\$\Omega\$). Please see https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf for the circuit diagram.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrData on September 01, 2018, 02:26:24 pm
Hello, can you guys help me out to find wich firmware goes with this device?

Thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on September 01, 2018, 06:42:02 pm
I don't know but the PCB looks nice. Programming header too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrData on September 01, 2018, 06:55:16 pm
It looks like the T3 but this has one extra button, so I'm not sure.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 01, 2018, 07:23:47 pm
Monochrome LCD?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 02, 2018, 03:55:45 pm
Hello, can you guys help me out to find wich firmware goes with this device?

Thanks in advance.

It is the same the clone under the name Fish8840 only covered with white paint.
Compare to photos which I have attached. The firmware for this clone can be taken from Karl-Heinz's distribution  in the "mega328_7565" folder. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: denimdragon on September 05, 2018, 02:26:39 am
OK, so I have been reading through this encyclopedia in bite-sized chunks (far to much to digest at one time) and I still haven't read the entire thread. I have been playing with my AY-AT for the last couple of days. These little devices are really amazing, well actually the coders (Karl & Markus-Both) are amazing. I'm a rookie but I've been doing analog here and there since I've been in school for the last couple of years. This was a perfect chance for me to get into both arenas.

I have a few questions (I'm an extremist, so bare with me...):


None of this might be worth the effort but I had to ask  :-//

P.S. I know the aim was to max out what was available with minor hardware adjustments so as not to conflict with the software...

Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on September 05, 2018, 02:58:23 am
The AVR only has (rather crappy) 10 bit ADCs.  Not much to gain with better refs and sub-0.1% resistors.

And yes, it could be ported to other processors and be pimped out seven ways to Sunday... but why bother?   The device is a VERY cute, VERY cheap hack,  and will not ever be a metrology grade universal test instrument.  It's operating principles don't allow it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 05, 2018, 11:06:52 am
Could this possibly be ported over to a ST32?

Basically yes, but you would need external switching for the 5V test voltage (IIRC the ST32 runs at 3.3V).

I've been really playing with the idea of adding a daughter board that uses a LT1021BMH-5 for the Vref. How much trouble would that be and would It make a significant difference in this application? I have a ton of these and some aged LM199AH/883QS and LM399AH. I plan on using external power.

That would be overdoing things with no real benefit. Anyhow, it can be done.

I'm also curious if I could use external ADC as well.

Of course you can. The drawback is that the circuitry would become more complex and also the firmware. As texaspyro has put so nicely, the tester's main value is its simplicity. KISS and don't over-engineer things ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: denimdragon on September 05, 2018, 02:27:15 pm
The AVR only has (rather crappy) 10 bit ADCs.  Not much to gain with better refs and sub-0.1% resistors.

And yes, it could be ported to other processors and be pimped out seven ways to Sunday... but why bother?   The device is a VERY cute, VERY cheap hack,  and will not ever be a metrology grade universal test instrument.  It's operating principles don't allow it.

As expected, and thanks for the input. Let me ask you, fellow Texan (assumption from your screen name), what concepts and operating principles would I need to keep in mind if I wanted to try something similar to this small form factor with the previously given criteria (granted I know It would be a larger footprint to make a device that's more accurate simply because of noise considerations and shielding/isolation issues)? As I mentioned, I'm an EE student (sophomore), and 7 ways til Sunday is a perfect project agenda for learning. I just don't want to go TOO far down the rabbit whole (my nick name is "Bugs")  :-DD

I think it will be fun to give it a shot and see what can be created with similar simplicity, just on steroids (a disclosure was given about my tendency to be extreme).




Basically yes, but you would need external switching for the 5V test voltage (IIRC the ST32 runs at 3.3V). -------> Correct, I considered this also.

I've been really playing with the idea of adding a daughter board that uses a LT1021BMH-5 for the Vref. How much trouble would that be and would It make a significant difference in this application? I have a ton of these and some aged LM199AH/883QS and LM399AH. I plan on using external power.

That would be overdoing things with no real benefit. Anyhow, it can be done.--------> Point taken and noted  :-+

I'm also curious if I could use external ADC as well.

Of course you can. The drawback is that the circuitry would become more complex and also the firmware. As texaspyro has put so nicely, the tester's main value is its simplicity. KISS and don't over-engineer things ;) --------> Yeah, I get it. I do want to attempt to build something like this but with better hardware and based on the STM32 as they are even cheaper than ATmega328 in most cases. The specs on it are far better and it would be fun to see how that chip could be maxed out. The cool thing about this particular project is the flexibility that comes from the ATmega. You guys have done things with the code that's utterly remarkable and fascinating to me. I'm just interested in attempting this with a bit more core horsepower. It's all in the name of learning.

Thank you both for the input  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on September 05, 2018, 03:27:57 pm
You would need better ADCs (start with ADS1115's?),   better drivers with regulated (and possibly adjustable) output voltage/current (don't use raw GPIO pins),  higher res timers, etc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 06, 2018, 02:33:20 pm
Hey Markus,
Thank you very much!

As far as I understood you replaced the following parts on the TC1/TC-1, right?

U4: post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1604254/#msg1604254)
D2: post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1762919/#msg1762919)
C11/12: post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1745051/#msg1745051)

What exact type have you used for D2?


Another question:

The next m-firmware version will include the settings for the TC-1 (in the "Clones" file).

Is there something like a "nightly build" or something like that? The Mikrocontroller SVN trunk-folder is not yours I guess?

I offer any kind of help (like measurements, testing, ...) for sure.

Cheers!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 06, 2018, 03:54:58 pm
As far as I understood you replaced the following parts on the TC1/TC-1, right?

U4: post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1604254/#msg1604254)
D2: post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1762919/#msg1762919)
C11/12: post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1745051/#msg1745051)

What exact type have you used for D2?

The next best Schottky diode I have in stock, an SB160. But I'd recommend to get something like a SS18 which matches the footprint and has a higher reverse voltage. 

Is there something like a "nightly build" or something like that? The Mikrocontroller SVN trunk-folder is not yours I guess?

Nope, I don't release any snapshots of the current source under development. But in some cases I provide a beta version to someone for testing a specific new feature. And the SVN is managed by Karl-Heinz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 06, 2018, 04:15:47 pm
Aii, thanks - I see  ;)

You furthermore listed some alternative options to make the TC1 fit the k/m firmware:

- write a new firmware for U4 (simple power_on signal from the ATmega and button press signal for the ATmega)
- replacing U4 with some transistors (standard power circuitry)

Is there a specific reason why you have choosen the "transistor option" instead of a new firmware?


P.S.: Some SO8 to DIP8 adapters:
https://www.cimarrontechnology.com/browndog-031101b-dip8-to-so8-adapter (https://www.cimarrontechnology.com/browndog-031101b-dip8-to-so8-adapter)
https://www.gotronik.pl/adapter-dip8-na-so8-p-2885.html (https://www.gotronik.pl/adapter-dip8-na-so8-p-2885.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 06, 2018, 05:02:48 pm
The mod with two transistors is very simple and also reduces the quiescent current. Otherwise I would have to get familiar with the other MCU, get a programmer and set up a complete tool chain.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 06, 2018, 05:41:55 pm
I understand... okay - makes sense ;) Another option you mentioned is reversing the protocol - what information would you need exactly? Why does the firmware not work on the TC-1? Is it just the "button pressed"-signal?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 06, 2018, 06:15:00 pm
U4 doesn't simply emulate the button signal (low when pushed) and seems to use some serial protocol to communicate with the ATmega instead.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 06, 2018, 09:08:23 pm
Ah yes I see, I just hooked up some logic analyzer as someone already did here: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1553443/#msg1553443

Looks like UART at a first glance, will dig a bit deeper and report back
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 06, 2018, 10:54:14 pm
@madires:
Okay, it is not too much communication happening between those two components.

U4, Pin 7 ---> ATmega PD1 / TXD0
U4, Pin 8 ---> ATmega PD2 / RXD1

I attached the communication i sniffed using one of those Saleae clones.
The comm. at a normal starup is built up of three parts:

1) The first one is on PD2 and is somehow optional, it sometimes is there and sometimes is not - don't know why
2) The second one is the one which was already observed in https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1553443/#msg1553443 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1553443/#msg1553443) (first on PD1 then PD2), it's exactly the same here.
3) As soon as the detection is finished, there is a last bit at PD1

If you long press the button to shutdown the tester, then there is again some sort of comm. on PD1.


I attached the sniffed data in Salea's format, as csv and pictures.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gtx21 on September 07, 2018, 05:38:20 am
It looks like BC557C's have been discontinued?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on September 07, 2018, 08:17:25 am
I don't think they are discontinued... Look e.g. here:
https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20180907001457&SearchText=BC557C (https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20180907001457&SearchText=BC557C)

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2018, 11:10:31 am
If you have difficulties to find a BC557C any jelly bean PNP with an I_C of 100mA or more and an hFE about 400-800 will do the job.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 07, 2018, 07:42:27 pm
@madires:
Looks like all you need to flash the STC15 is a USB-to-TTL adapter (see e.g. here: http://grauonline.de/wordpress/?p=44 (http://grauonline.de/wordpress/?p=44)).
Furthermore the uC's is 8051 compatible - should be easy to write a new firmware therefore, right?
Maybe we can collaborate somehow? What exactly does the ATmega expect? LOW on a pressed button, right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2018, 11:10:10 pm
Of course! The standard firmware expects the button signal to be high when not pushed and low when pushed. It has to stay low as long as the button is pushed. The power-on signal is generated to keep the circuit powered. After the ATmega is powered on the firmware sets the power-on signal high, and when the tester should be powered down the signal is set to low. So U4 would simply sleep and wait for a button press. When the button is pressed it has to enable to boost converter to power the circuit and provide a low signal to the ATmega as long as the button is pressed. At the same time U4 has to check the power-on signal and disable the boost converter when the signal changes to low. Allow some delay for the power-on signal being set to high by the ATmega after enabling the boost converter (startup time of the ATmega).
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 08, 2018, 04:36:00 am
I assembled my AY-AT clone with a MCP1702-5002 5 V regulator. Since that regulator accepts up to 13.2 V, does that mean I can power my tester with 12 V?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 08, 2018, 10:05:25 am
Yes, 12V should be OK. But with 9V less power would be dissipated as heat.
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 08, 2018, 12:38:37 pm
If I use two lithium-ion 18650 cells, they would get over-discharged, right? because the regulator will try to take as little as ~5.6 V (2.8 V per cell)? Could I just use a diode with a voltage drop of 0.7 V between the cells and the device so it will stop working when the batteries reach ~3.2 V per cell? Can any of the firmwares detect the input voltage to tell when the batteries are low. It would be cool if it could be told they were a lithium battery and turn off at 6.4 V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 08, 2018, 01:02:51 pm
You can set the threshold voltages for the battery monitoring. For the m-firmware that would be BAT_WEAK and BAT_LOW in config.h. Also adjust BAT_OFFSET (for the PNP switching power). Both firmwares (k and m) display the battery voltage and switch off when the voltage is too low.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 08, 2018, 06:31:50 pm
This is the current setup for U4:

Checking target MCU ...
  MCU type: STC15L104W
  F/W version: 7.2.5Q

Current H/W Option:
  . Current system clock source is internal IRC oscillator
  . IRC frequency: 11.051MHz
  . Wakeup Timer frequency: 27.155KHz
  . Do not detect the level of P3.2 and P3.3 next download
  . Power-on reset, use the extra power-on delay
  . RESET pin behaves as I/O pin
  . Reset while detect a Low-Voltage
  . Thresh voltage level of the built-in LVD : 2.42 V
  . Inhibit EEPROM operation under Low-Voltage
  . Hardware do not enable Watch-Dog-Timer
  . Watch-Dog-Timer pre-scalar : 256
  . Watch-Dog-Timer stop count in idle mode
  . Program can modify the Watch-Dog-Timer scalar
  . Do not erase user EEPROM area at next download
  . Do not control 485 at next download
  . Do not check user password next download
  . TXD is independent IO
  . TXD pin as quasi-bidirectional mode after reset
  . P3.3 output HIGH level after reset
  . Testing time: 2017-11-13

  . MCU type: STC15L104W
  F/W version: 7.2.5Q


At least no protection! Going to write a new one now... I will let you know
@madires: Is there anything I need to modify at your firmware? Can you provide me a "ready to flash" hex file - so I can concentrate on U4 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 08, 2018, 08:41:24 pm
The AY-AT clone I bought comes with version 1.12 firmware. Why so old (five years)? I have to wait for my replacement IC to arrive since I want to keep the original one in case I fail every attempt to flash the latest firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on September 08, 2018, 09:21:03 pm
This is the current setup for U4:

Checking target MCU ...
  MCU type: STC15L104W
  F/W version: 7.2.5Q

Flodo, great work.  Did you download the current f/w.  Can you post it or PM it to me, I would like to try and look at the code to figure out the data stream it sends and expects to receive from the ATMega. That way we might be able to add routines to the ATMega for the TC1 to work without hardware modification.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 08, 2018, 09:26:26 pm
@azure: you cannot dump the flash from STC chips. the (hardcoded) bootloader simply does not support that. Therefore our best bet is to reprogram it, thats what I am trying at the moment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: logic021 on September 09, 2018, 08:04:40 am
Need help.
I have GM328A with faulty TEST pin 2.
1. Measurements between pin 1 and 3 is OK.
2. Test pcb lines from ZIF to IC - OK
3. Tested IC with blink program:
    direct pins 23,23,25  - OK
    resistor pins 12,13,14,15,16,17  - OK

I tried with another IC - the same result







Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 09, 2018, 11:20:22 am
This is the header you need for U4: https://gist.github.com/atar-axis/430ae53213e2c193e8c3eaa9e89eb21f (https://gist.github.com/atar-axis/430ae53213e2c193e8c3eaa9e89eb21f)
I also attached a pinout of U4, as you can see it is easy to access MCU RxD and TxD via P1 and P2.

@madires:
I flashed a first mockup for U4's fw, can you maybe give me some instructions for modifying your atmega_fw appropriately for  the TC1? (maybe you can even give me yours?)




P.S.: Here is another, more detailed diagram by user zappenduster: https://www.eevblog.com/forum/testgear/tc1-lcr-meter-transistor-tester-fix/ (https://www.eevblog.com/forum/testgear/tc1-lcr-meter-transistor-tester-fix/))
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 09, 2018, 01:19:35 pm
@madires: Is there anything I need to modify at your firmware? Can you provide me a "ready to flash" hex file - so I can concentrate on U4 :)

The settings for the TC1 are:

Code: [Select]
Hardware Options:
#define HW_REF25
#define HW_ZENER
#define HW_IR_RECEIVER
#define HW_ADJUST_CAP

Misc settings:
#define BAT_DIRECT
#define BAT_OFFSET       0
#define BAT_WEAK         3700
#define BAT_LOW          3500

LCD module:
#define LCD_ST7735
#define LCD_COLOR                       /* color graphic display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTB          /* port data register */
#define LCD_DDR          DDRB           /* port data direction register */
#define LCD_RES          PB4            /* port pin used for /RESX (optional) */
//#define LCD_CS           PB?            /* port pin used for /CSX (optional) */
#define LCD_DC           PB5            /* port pin used for D/CX */
#define LCD_SCL          PB7            /* port pin used for SCL */
#define LCD_SDA          PB6            /* port pin used for SDA */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       160            /* number of vertical dots */
//#define LCD_FLIP_X                      /* enable horizontal flip */
#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_ROTATE                      /* switch X and Y (rotate by 90°) */
#define LCD_LATE_ON                     /* turn on LCD after clearing it */
#define LCD_OFFSET_X     2              /* enable x offset of 2 or 4 dots */
#define LCD_OFFSET_Y     1              /* enable y offset of 1 or 2 dots */
#define FONT_10X16_HF                   /* 10x16 font, horizontally aligned & flipped */
//#define FONT_8X16_CYRILLIC_HF           /* 8x16 cyrillic font, horizontally aligned & flipped */
#define SYMBOLS_30X32_HF                /* 30x32 symbols, horizontally aligned & flipped */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SDA        /* port pin used for MOSI */

Pinout for test probes:
#define TP_ZENER         PA4       /* test pin with 10:1 voltage divider */
#define TP_REF           PA3       /* test pin with 2.5V reference */
#define TP_BAT           PA5       /* test pin with 4:1 voltage divider */
#define TP_CAP           PA7       /* test pin for self-adjustment cap */

Pinout for probe resistors:
#define R_PORT           PORTC     /* port data register */
#define R_DDR            DDRC      /* port data direction register */
#define R_RL_1           PC0       /* Rl (680R) for test pin #1 */
#define R_RH_1           PC1       /* Rh (470k) for test pin #1 */
#define R_RL_2           PC2       /* Rl (680R) for test pin #2 */
#define R_RH_2           PC3       /* Rh (470k) for test pin #2 */
#define R_RL_3           PC4       /* Rl (680R) for test pin #3 */
#define R_RH_3           PC5       /* Rh (470k) for test pin #3 */

Pinout for test button and power management:
#define CONTROL_PORT     PORTD     /* port data register */
#define CONTROL_DDR      DDRD      /* port data direction register */
#define CONTROL_PIN      PIND      /* port input pins register */
#define POWER_CTRL       PD2       /* controls power (1: on / 0: off) */
#define TEST_BUTTON      PD1       /* test/start push button (low active) */

Pinout for fixed IR detector/decoder:
#define IR_PORT          PORTD     /* port data register */
#define IR_DDR           DDRD      /* port data direction register */
#define IR_PIN           PIND      /* port input pins register */
#define IR_DATA          PD3       /* data signal */

Pinout for fixed cap for self-adjustment:
#define ADJUST_PORT      PORTC     /* port data register */
#define ADJUST_DDR       DDRC      /* port data direction register */
#define ADJUST_RH        PC6       /* Rh (470k) for fixed cap */

PD1 is the input for the button and PD2 is the output for switching power.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 09, 2018, 01:26:15 pm
I have GM328A with faulty TEST pin 2.

I tried with another IC - the same result

Did test pin 2 work before? You could try to remove IC SRV05-4.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 09, 2018, 02:30:34 pm
Thanks madires!
Is the attached behaviour correct?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 09, 2018, 03:29:37 pm
Yep, the signals look fine. To reduce the quiescent current it could be a good idea to keep the button signal for the ATmega low when the boost converter isn't enabled. What do you think?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 09, 2018, 03:33:23 pm
Okay, will do that afterwards :D

The TC1 is starting up now with U4's new FW, but...
* the display is flipped and [fixed by commenting out 'LCD_FLIP_X' and commenting 'LCD_FLIP_Y']
* once online the device is testing and so on, afterwards it says IMMEDIATELY 'bye' - there is no delay, you cannot even read the values
* it then stops there, the device is not yet shutting down after that - or, sometimes, it starts again and again after the "bye" being displayed, think there is still something wrong with the FSM

thats something we can fix I guess :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 09, 2018, 04:34:50 pm
Ups, looks like the endless "testing loop" is by design, right? (It does only shut down if no component is detected for x iterations, otherwise it is testing every 3 seconds or so)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 09, 2018, 04:39:17 pm
Have you set the MCU clock to 16MHz in the Makefile? When the tester is started in "continuous mode" (short key press at start-up) it will run the test cycles continuously and power down if nothing is found for five times in a row. There's also an auto-hold mode which is selected by powering on the tester with a long key press (>300ms). And a very long key press (2s) will reset some values.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 09, 2018, 04:41:34 pm
found it, yes it is by design  8)

therefore the new U4 firmware is working :P
will have to change some details and will publish it afterwards with some informations on how to upload it to the TC1.
(debouncing, sleep mode and thing like that are still missing)

thanks for your support and your efforts!


edit: yes i made those Makefile changes you mention :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 09, 2018, 09:04:55 pm
I somehow damaged the strong drivers of my STC ... :-// Unfortunately it will take some days or maybe weeks to get a new one here in Germany. Maybe someone has an idea where I can get a new one faster?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on September 09, 2018, 11:03:29 pm
The AY-AT clone I bought comes with version 1.12 firmware. Why so old (five years)?

If it ain't broke, don't fix it; time is money; etc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 10, 2018, 03:19:50 am
Fortunately I was mistaken, my STC U4 is still alive.


I attached the first firmware version for TC1 U4 (without any kind of power saving mode, will do that later).

How To:
Just grab any kind of USB-to-UART(3V3) Adapter, hook up...
* TXD (Stick) to P1,
* RXD to P2 and
* GND to GND

Download the STC-ISP Software, leave everything as it is and select the firmware.
Press "Download/Program" and now hook up 3V3 at VCC (power the IC).
Wait for the firmware being uploaded.

That's it.


I am not yet 100% sure if it behaves correctly, I would appreciate any video of 1.33m


https://github.com/atar-axis/tc1-u4/releases
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2018, 06:36:00 am
Fortunately I was mistaken, my STC U4 is still alive.
I am not yet 100% sure if it behaves correctly, I would appreciate any video of 1.33m
flodo,сan you make small video of work of the LCR-TC1 with a new firmware U4? :)
What settings for STC-ISP software need to be made? In this program there are a lot of additional points.
Did you use stc-isp6.86?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 10, 2018, 08:38:19 am
flodo,сan you make small video of work of the LCR-TC1 with a new firmware U4? :)

I think it is better to wait for a video from someone with the transistor-mod since I am not sure if it behaves correctly.

What settings for STC-ISP software need to be made? In this program there are a lot of additional points.

Just leave everything as it is (at least for now).

Did you use stc-isp6.86?

Jap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 10, 2018, 09:32:04 am
Regarding editing 'config.sh', why do some entries have only a # while others have //#? I understand that the # comments-out options but does that mean to enable the servo check I should remove only the # and leave the // or should I remove both to enable? Thanks.

Code: [Select]
/*
 *  color coding for probes
 *  - requires color graphics LCD
 *  - uncomment to enable
 *  - edit colors.h to select correct probe colors
 */

#define SW_PROBE_COLORS


/*
 *  Servo Check
 *  - requires additional keys and display with more than 2 text lines
 *  - uncomment to enable
 */

//#define SW_SERVO

Also for the battery offset setting, I don't think my AY-AT clone has a reverse voltage protection diode - is that a bad design? Should I just measure the voltage drop across the 9014 transistor next to the LED at the top of the board?

Code: [Select]
/*
 *  Voltage drop by reverse voltage protection diode and power management
 *  transistor (in mV):
 *  - Schottky diode about 200mV / PNP BJT about 100mV.
 *  - Get your DMM and measure the voltage drop!
 *  - Could be also used to compensate any offset by the voltage divider
 *    used to measure the battery voltage.
 */ 

#define BAT_OFFSET       290
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 10, 2018, 10:11:47 am
In C '#' is not a comment but a preprocessor directive ;) Remove '//' to enable
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 10, 2018, 10:18:04 am
In C '#' is not a comment but a preprocessor directive ;) Remove '//' to enable

Thanks. Do you know why some options have //# while others only have #? Are the # options the default in case nothing is changed?

Also, I notice inductance measurement is disabled by default. Is there some disadvantage to enabling inductance measurement on some testers? I have an AY-AT clone.

Code: [Select]
*
 *  Inductance measurement
 *  - uncomment to enable
 */

#define SW_INDUCTOR
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 10, 2018, 10:54:44 am
If a line starts with "//", then it is a comment :)
Therefore "//#" means that this specific option is commented out.

If a line does not have a leading "//" (like #define BAT_OFFSET       290) then it is not commented out...

But there is another kind of comments which :
/* this is a
multiline
comment
*/



Beside commenting out, you can also disable options by using preprocessor directives:
#if 0 ... #endif,
you can enable those blocks by changing the 0 to 1 like:
#if 1 ... #endif


Regarding the AY-AT questions: I don't know

Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 10, 2018, 11:27:11 am
If a line does not have a leading "//" (like #define BAT_OFFSET       290) then it is not commented out...

Are you sure? The following code is what appears in the config.h file I downloaded. It says uncomment to enable which suggests that it's disabled by default and you need to remove the # to uncomment the option. Shouldn't it say "comment to disable" instead of "uncomment to enable" if # is not a comment marker?

Code: [Select]
/*
 *  Enter sleep mode when idle to save power.
 *  - uncomment to enable
 */

#define SAVE_POWER
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 10, 2018, 11:48:19 am
Yes, I am 100% sure  ;) ^-^ It reads "Uncomment to enable" so, since it is already uncommented, it is enabled. Someone wrote that when it was commented out by default, but it isn't anymore.

If you still don't believe me, google for "preprocessor directive C" - e.g.: http://www.cplusplus.com/doc/tutorial/preprocessor/ (http://www.cplusplus.com/doc/tutorial/preprocessor/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 10, 2018, 12:08:54 pm
flodo,сan you make small video of work of the LCR-TC1 with a new firmware U4? :)

https://www.youtube.com/watch?v=v-vgg87bcjI (https://www.youtube.com/watch?v=v-vgg87bcjI)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2018, 01:13:55 pm
Also, I notice inductance measurement is disabled by default. Is there some disadvantage to enabling inductance measurement on some testers? I have an AY-AT clone.

Code: [Select]
*
 *  Inductance measurement
 *  - uncomment to enable
 */

#define SW_INDUCTOR

The inductance measurement is enabled by default for all testers. Please don't get confused by the '#'. In an unix shell script it would be a comment, but in C it's a directive for the preprocessor as flodo has explained already. And the '//' is used to indicate a comment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2018, 01:20:37 pm
Are you sure? The following code is what appears in the config.h file I downloaded. It says uncomment to enable which suggests that it's disabled by default and you need to remove the # to uncomment the option. Shouldn't it say "comment to disable" instead of "uncomment to enable" if # is not a comment marker?

Code: [Select]
/*
 *  Enter sleep mode when idle to save power.
 *  - uncomment to enable
 */

#define SAVE_POWER

Copy and paste ;) In this case the feature is enabled by default (it's starting with the #define directive). If you want to disable it you'd insert a '//' in front of the '#define':
Code: [Select]
//#define SAVE_POWER

The 'uncomment to enable' implies a "comment out to disable'. You'll learn all this when you start programming in C ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2018, 01:37:01 pm
flodo,thanks for video - the program works normally, I don't see any problems in work of a tester. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2018, 01:41:40 pm
flodo,сan you make small video of work of the LCR-TC1 with a new firmware U4? :)

I think it is better to wait for a video from someone with the transistor-mod since I am not sure if it behaves correctly.

If you press the button for at least 300ms at power-on the tester will enter the auto-hold mode (no cycling, blinking cursor at the bottom right). And after displaying the result of the last check two short button presses will trigger the menu. If this is working fine your firmware for U4 should also run without any problems with the k-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2018, 01:59:02 pm
Still it is possible to change an operating mode of the Test button in config.h
#define UI_AUTOHOLD  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 10, 2018, 03:26:52 pm
If you press the button for at least 300ms at power-on the tester will enter the auto-hold mode (no cycling, blinking cursor at the bottom right). And after displaying the result of the last check two short button presses will trigger the menu. If this is working fine your firmware for U4 should also run without any problems with the k-firmware.

Like this?

https://www.youtube.com/watch?time_continue=1&v=tloRxvvWxuc (https://www.youtube.com/watch?time_continue=1&v=tloRxvvWxuc)

Btw, looks like the battery settings are wrong - right (15.x V)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2018, 03:57:56 pm
Yep, but I've noticed some bad characters/texts in the menu. Have you updated also the EEPROM? And yes, the battery voltage is wrong. My guess is that BAT_DIRECT isn't enabled (BAT_NONE and BAT_DIVIDER need to be disabled).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2018, 05:08:42 pm
The wrong voltage of the battery and excess symbols are small malfunctions which are easily corrected.
Config.h
#define BAT_R1           0
#define BAT_R2           1
The most important that management by the Test button works without problems. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2018, 06:04:43 pm
Those settings are for older versions (IIRC, before 1.32m).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2018, 06:11:50 pm
I have opened the config.h file from your distribution kit 1.33m. In him I see these settings:
/*
 *  Voltage divider for battery monitoring
 *  - BAT_R1: top resistor in Ohms
 *  - BAT_R2: bottom resistor in Ohms
 */
#define BAT_R1           10000
#define BAT_R2           3300

 It is wrong or doesn't work any more?
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 10, 2018, 06:39:17 pm
My AY-AT clone doesn't turn itself off if left alone for several minutes and also doesn't turn off if I try to switch it off manually. If I use the rotary encoder to self "switch off", the screen refreshes and the tester doesn't switch off. Does this suggest a fault? I hope to replace the microcontroller with one flashed with 1.33 (m-firmware) whilst it the one it came with is running 1.12.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2018, 06:53:20 pm
I have opened the config.h file from your distribution kit 1.33m. In him I see these settings:
/*
 *  Voltage divider for battery monitoring
 *  - BAT_R1: top resistor in Ohms
 *  - BAT_R2: bottom resistor in Ohms
 */
#define BAT_R1           10000
#define BAT_R2           3300

 It is wrong or doesn't work any more?

They work, but they are meant for BAT_DIVIDER. BAT_DIRECT ignores them and the firmware will be a few bytes smaller. Therefore BAT_DIRECT is the preferred setting in case of a direct battery monitoring without any voltage divider.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2018, 06:59:38 pm
My AY-AT clone doesn't turn itself off if left alone for several minutes and also doesn't turn off if I try to switch it off manually. If I use the rotary encoder to self "switch off", the screen refreshes and the tester doesn't switch off. Does this suggest a fault? I hope to replace the microcontroller with one flashed with 1.33 (m-firmware) whilst it the one it came with is running 1.12.

Yes, there's something wrong with your tester. Please check the power control signal (ATmega328 PD6). It should change to low when powering off.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 10, 2018, 09:55:00 pm
I attached linked to TC1 U4 firmware v0.2 - the standy mode should work now: https://github.com/atar-axis/tc1-u4/releases
The TC1 standby power consumption seems to be around 0.11mA, so my 2000mAh battery should - in theory and when disregarding self-discharging - last for around 2 years standby. That's okay but not really good... According to the datasheet the consumption of U4 is lower than 0.1uA in power-saving mode, so what is drawing so much power?

@madires: have you ever measured the consumption? what are your results?


Another question: are there any graphics somewhere like in the shipped firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 10, 2018, 11:22:49 pm
My AY-AT clone doesn't turn itself off if left alone for several minutes and also doesn't turn off if I try to switch it off manually. If I use the rotary encoder to self "switch off", the screen refreshes and the tester doesn't switch off. Does this suggest a fault? I hope to replace the microcontroller with one flashed with 1.33 (m-firmware) whilst it the one it came with is running 1.12.

Yes, there's something wrong with your tester. Please check the power control signal (ATmega328 PD6). It should change to low when powering off.

PD6 remains at 5 volts when I select "switch off". The LED at the top of the PCB turns off whilst the rotary encoder is held down but the voltage on PD6 stays on and when the rotary encoder is released, the screen refreshes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 11, 2018, 10:24:53 am
The TC1 standby power consumption seems to be around 0.11mA, so my 2000mAh battery should - in theory and when disregarding self-discharging - last for around 2 years standby. That's okay but not really good... According to the datasheet the consumption of U4 is lower than 0.1uA in power-saving mode, so what is drawing so much power?

@madires: have you ever measured the consumption? what are your results?

Not yet, but zappenduster did (15µA).

Another question: are there any graphics somewhere like in the shipped firmware?

Just the symbols for 3-pin semiconductors. Graphics which automatically scale to the screen resolution and font size would increase the firmware size considerably.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 11, 2018, 10:34:58 am
PD6 remains at 5 volts when I select "switch off". The LED at the top of the PCB turns off whilst the rotary encoder is held down but the voltage on PD6 stays on and when the rotary encoder is released, the screen refreshes.

Remove the ATmega, press and hold the rotary encoder and measure the voltage at PD6.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 11, 2018, 04:41:31 pm
Unfortunately my U4 (STC15L104W) is now dead after all... (yes, this time it really is  :-[)
If someone in europe can offer me a new one, or tell me where I can buy one, i would really appreciate it.

Update:
After searching for a while: You can replace the STC15L104W by a STC15W104 or STC15W204. In fact I would recommend to do so because a fully charged Battery is around 4.2V, in this case there are still around 4.0V at U4 behind the diode. The absolute maximum rating of the STC15L104W is 3.6V, the STC15W104/204 has a maximum of 5.5.
Yes, I know - 0.4V will surely not destroy the IC... but it is a bad design anyway, there is not even a voltage regulation for U4.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 12, 2018, 06:50:28 am
There are 2 options of a chip STC15L104 with power 2,4-3.6v and STC15F(W)104 with power 3.8-5.5v, then for option with STC15F104 the diode which I have marked red in the drawing is necessary, and for option with STC15L104 - isn't necessary and is even harmful because it overestimates supply voltage by 30% above passport!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 12, 2018, 11:05:54 am
@indman:
The STC15Wxxx is rated for 2.4 - 5.5V (not 3.8 - 5.5V like the STC15Fxxx). So the diodes shouldn't be a problem, right? Neither D3 nor D0.
Not essentially what lower threshold of voltage(2.4v or 3.8v), it is possible to use any of the chips.The main thing that top  voltage makes 5.5v.I have shown the D0 diode on a photo :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on September 12, 2018, 11:06:37 am
But, where is D0 on the PCB? I didn't knew about this one.

On the circuit I have drawn for the TC! I have that D0 in Indmans drawing drawn as D4, not sure if that helps you flodo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 12, 2018, 11:14:39 am
Yep, D3 is needed to power U4. And D0's purpose seems to be to bring U4's I/O pins up to nearly 5V to match the ATmega.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 12, 2018, 11:22:34 am
I removed my last comment because it was totally misleading.
Let's see if I got it right now:

There are at least three variants of the STC15:

U4 is powered by the battery (via D3) as long as the 78L05 is not up yet - right? Therefore, U4 is powered by 3.5-4.0V (3.7-4.2V minus voltage drop at D3) at startup. The point is, 4.0V is too high for the STC15Lxxx and 3.5V is too low for the STC15Fxxx
U4 is then enabling the step-up (U5, SD6271) at start-up, which powers, among others, the 78L05.

Now, since the 78L05 is up, the voltage at U4 is now 4.8V (5V - 0.2V D0 drop) - which is even higher and therefore much too high for the STC15Lxxx.


The only one which does really fit both phases is the STC15Wxxx.
Removing D0 is not really a clean solution since then the I/O ports are at another level as the ATmega is.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 12, 2018, 11:32:37 am
You got it right! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on September 12, 2018, 12:15:52 pm
I have shown the D0 diode on a photo :)

Indman, do you have a link to that complete circuit.  I would like to compare it to the one I have drawn.  I have attached my current one.

Note: LCD sub pcb is not correct on my drawing as I just started adding in the parts for it.

I see D3 not only as a voltage drop to U4, it blocks the 5V from feeding back to the USB Lipo charger and D4 stops the V+ from the 5V supply.

I think the U4 L/F/W part numbers are worth looking into in respect to the opersting voltsges.  One concern is the F may not start up when the battery is a little low on its voltage (Edit: As flodo said in the previous post)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 12, 2018, 12:57:41 pm
https://yadi.sk/d/yW8xa5NJgUo5z (https://yadi.sk/d/yW8xa5NJgUo5z)
You can download the schematic diagram on many clones which I have collected in one archive at this link. You come into the "LCR-T1" folder - inside there are folder "Schematic diagram" and the TC-1.spl7 file. At me isn't present in LCR-T1 clone hands. This scheme was drawn by one of owners sleska of such device from the Russian website vrtp.ru.
It is possible to open the *.spl file the SPLan program - demo version is located here https://www.electronic-software-shop.com/lng/en/demo-versionen/ (https://www.electronic-software-shop.com/lng/en/demo-versionen/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 12, 2018, 01:10:50 pm
@indman: Could you please export the splan-schematic to pdf for me? i am running linux  ;D
@Azure: FIY, the U5 boost-IC is a SD6271 :) The "697" behind "AL" is just a LOT number :P
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 12, 2018, 01:22:15 pm
Ok,flodo, the picture in a JPG format will suit you? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 12, 2018, 01:29:08 pm
For sure! Thank you very much :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 12, 2018, 08:12:22 pm
PD6 remains at 5 volts when I select "switch off". The LED at the top of the PCB turns off whilst the rotary encoder is held down but the voltage on PD6 stays on and when the rotary encoder is released, the screen refreshes.

Remove the ATmega, press and hold the rotary encoder and measure the voltage at PD6.

With the ATmega removed and the rotary encoder held down, the voltage is ~4.5 V at PD6. When the rotary encoder is released, this decreases to 4.2 V. I hope that says something useful!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 13, 2018, 09:43:00 am
It does. ;) We can exclude the ATmega, and the next step is to to check T1 which is switched by PD6.
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 13, 2018, 09:56:07 pm
It does. ;) We can exclude the ATmega, and the next step is to to check T1 which is switched by PD6.

I wonder if I might have damaged something. It turned out that pins of the transistor highlighted below were shorted by a bridge of solder. Now that I've removed the bridge, the tester only comes on if I press and hold the rotary encoder down. As soon as I release the rotary encoder, the tester turns off. Would this short-circuit between the base and collector of that transistor cause damage to another component (maybe that transistor itself)?

(https://imgur.com/ajksq3O.png)
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEV2K on September 13, 2018, 10:04:56 pm
Hi eevblog,

I bought a TransistorTester similar to T4 (but not identical, LCR-T4) awhile ago but the LCD is broken and I tried to replace it with Nokia 5110 (PCD8544).  Markus's version supports Nokia 5110 so I flash the board with ComponentTester-1.33m but it's not working.  By the way, I am new to avr so there will be mistakes.

Hardware:
Code: [Select]
//---------------
//TransistorTester/ComponentTester T4 Clone with PCD8544
//Atmega328 8MHz
//PCD8544 (bit-bang SPI)
//---------------
//Nokia 5110:
//1: VCC - 3.3V
//2: GND - GND
//3: SCE - GND
//4: RST - 10K - PD4 (2)
//5: D/C - 10K - PD3 (1) - Data/Command
//6: DN(MOSI) - 10K - PD5 (9)
//7: SCLK - 10K - PD2 (32)
//8: LED - 100R - 5V
// Note: it does not work when RST=PD0, and DIN=PD1, PD0 and PD1 are serial RX and TX, maybe that is the reason

display     config-<MCU>.h   default   remark
                               328
  /RES        LCD_RES          PD4       optional
  /SCE        LCD_SCE          GND       optional
  D/C         LCD_DC           PD3
  SCLK        LCD_SCLK         PD2
  SDIN        LCD_SDIN         PD5
Later on I also added a serial port interface to try to figure out what is wrong.

Files changed:
Code: [Select]
Makefile - No change
config.h:
  Line 082: uncomment #define HW_REF25 to enable hardware reference
  Line 307: comment out #define SW_PROBE_COLORS to diable color coding
  Line 396: uncomment #define UI_SERIAL_COPY
  Line 406: uncomment #define UI_SERIAL_COMMANDS
  Line 689: uncomment #define SERIAL_HARDWARE
config_328.h:
  Line 099: uncomment #if 0 .. #endif ;to disable LCD_ST7565R
  Line 203: change to #if 1 ;to enable LCD_PCD8544 or comment it out
  Line 209: change to PD4
  Line 210: comment out #define LCD_SCE ;since this is connected to GND
  Line 213: change to PD5
Clones - No change
variables.h - No change so far

At present, after writing the firmware with avrdude to ATMega328P, I push the blue test button.  A short push, the back light on LCD turns on, so there is power, but nothing on the screen.  Voltage measured 5.05V at the ISP programming port, ~3V at LCD.   Serial port shows "Component Tester v1.33m".  Once the button is up, it's off.   I am not sure if this is normal or maybe POWER_CTRL(PD6) is not working properly.

A long push, back light turns on, nothing on the LCD, serial port shows "Component Tester v1.33m" and after a short while "No component found!".  I think this means EEPROM is working and the logic of the firmware is being followed.

To help figure out things, I modified main.c so I can test individual components of the firmware and the hardware:
Code: [Select]
#if defined(__AVR_ATmega328__)

  #if (CPU_FREQ != 8000000)
    #error <<< KK: Error CPU FREQ is not 8MHz >>>
  #endif
 
  #ifndef LCD_PCD8544
    #error <<< KK: Error LCD is not PCD8544 >>>
  #endif
 
  #ifdef SPI_HARDWARE
  #error <<< KK: Error using SPI hardware instead of bitbang >>>
  #endif
 
  #ifndef SPI_BITBANG
  #error <<< KK: Error not using SPI bitbang >>>
  #endif
 
  #if (SPI_SCK != PD2)
  #error <<< KK: Error SPI_SCK != PD2 >>>
  #endif
 
  #if (SPI_MOSI != PD5)
  #error <<< KK: Error SPI_MOSI != PD1 >>>
  #endif
 
  #if (POWER_CTRL != PD6)
  #error <<< KK: Error POWER_CTRL != PD6 >>>
  #endif

  #if (TEST_BUTTON != PD7)
  #error <<< KK: Error TEST_BUTTON != PD7 >>>
  #endif

  #ifndef HW_SERIAL
  #error <<< KK: Error serial port (HW) is off >>>
  #endif

  #ifdef SERIAL_RW
  #error <<< KK: Error serial port (RW) is on >>>
  #endif

  #ifdef HW_TOUCH
  #error <<< KK: Error touch support is on >>>
  #endif
 
  #ifndef LCD_SPI
  #error <<< KK: SPI for LCD is off >>>
  #endif

  #define KK_DEBUG
  #define KK_DEBUG_OVERRIDE
 
#else
  #error <<< KK: Configuration Error >>>
#endif

void KK_Debug1(void)
{
  //KK: 100Hz toggle PD1
  DDRD = (1 << PD1); //Make PORTD1 an output pin by setting it to 1
  while(1) //infinite loop
  {
    PORTD = (1 << PD1); //Turns ON LED at PD1 by setting it 5V
    _delay_ms(5); //5ms delay
    PORTD= 0x00; //Turns OFF All LEDs
    _delay_ms(5); //5ms delay
  }
}

void KK_Debug2(void)
{
  //KK: serial: output A to Z
  uint8_t cc = 65;
  Serial_Setup();
  while(1) //infinite loop
  {
    Serial_WriteByte(cc);
    _delay_ms(50); //50ms delay
    cc++;
   if (cc>90) cc=65;
  }
}

void KK_Debug3(void)
{
  //KK: LCD: output A to Z
  uint8_t cc;
  LCD_BusSetup();                       /* set up LCD bus */
  LCD_Init();                           /* initialize LCD and clears the LCD*/
  UI.LineMode = LINE_STD;               /* reset next-line mode */
  while(1) //infinite loop
  {
    LCD_Clear();                        /* display was initialized before */
    cc = 65;
    while(cc<91) {
    LCD_Char('X');
      _delay_ms(50); //50ms delay
      cc++;
    }
    _delay_ms(2000); //2s delay
  }
}

void KK_Serial_WriteBits(uint8_t cc)
{
uint8_t i=0;
while(i<8)
{
if (cc & (1<<i))
Serial_WriteByte('1');
else
Serial_WriteByte('0');
  i++;
}
Serial_WriteByte('b');
Serial_WriteByte('\r');
Serial_WriteByte('\n');
}

void KK_Debug4(void)
{
  //KK: LCD: output A to Z
  uint8_t cc, bb;
  Serial_Setup();
  LCD_BusSetup();                       /* set up LCD bus */
  LCD_Init();                           /* initialize LCD and clears the LCD*/
  UI.LineMode = LINE_STD;               /* reset next-line mode */
  while(1) //infinite loop
  {
    LCD_Clear();                        /* display was initialized before */
    cc = 65;
    bb = DDRD;
  KK_Serial_WriteBits(bb);  //1 is output, so DDRD should be 00111100b, hardware serial is used so bit 0 and 1 is probably ignored
    while(cc<91) {
    LCD_Char(cc);
      _delay_ms(50); //50ms delay
      cc++;
    }
    _delay_ms(2000); //2s delay
  }
}

void KK_Debug_SW(void)
{
  KK_Debug4();
}


/* ************************************************************************
 *   the one and only main()
 * ************************************************************************ */

/*
 *  main function
 */

int main(void)
{
  uint8_t           Test;          /* test value */
  uint8_t           Key;           /* user feedback */
  #if defined (HW_REF25) || ! defined (BAT_NONE)
  uint16_t          U_Bat;         /* voltage of power supply */
  uint32_t          Temp;          /* some value */
  #endif

  #ifdef KK_DEBUG_OVERRIDE
  KK_Debug_SW();
  #endif


  /*
   *  init hardware
   */

The code above replaces the beginning of the main function.  So the #error's are tested after config.h and config_328.h are loaded and there is no unexpected configuration errors as far as I can tell since make compiles the code just fine.  I used KK_Debug1(), to test all the pins that I modified to make sure the connections are good.  Frequency measurement of the output measured 100Hz, so 328P is running at 8MHz. KK_Debug2() showed serial port is working but KK_Debug3() and KK_Debug4() is not working - nothing is displayed on the LCD.  Serial output of KK_Debug4() showed DDRD is 00111100b.  This, I think, showed the port direction are probably configured.  To make sure LCD is connected correctly, I tested it with examples that come with Adafruit_PCD8544 library in ArduinoIDE.  It displays animated smiles correctly.

So now I am stuck and I need help with what to do next.

Thanks.


edited: typo last paragraph disabled -> displayed
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 14, 2018, 09:50:21 am
I wonder if I might have damaged something. It turned out that pins of the transistor highlighted below were shorted by a bridge of solder. Now that I've removed the bridge, the tester only comes on if I press and hold the rotary encoder down. As soon as I release the rotary encoder, the tester turns off. Would this short-circuit between the base and collector of that transistor cause damage to another component (maybe that transistor itself)?

Yes, T1 could be damaged. The ATmega should be protected by the base resistor R8 (limiting current) and its internal clamping diodes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 14, 2018, 10:09:22 am
At present, after writing the firmware with avrdude to ATMega328P, I push the blue test button.  A short push, the back light on LCD turns on, so there is power, but nothing on the screen.  Voltage measured 5.05V at the ISP programming port, ~3V at LCD.   Serial port shows "Component Tester v1.33m".  Once the button is up, it's off.   I am not sure if this is normal or maybe POWER_CTRL(PD6) is not working properly.

The first thing to investigate is the power control circuitry. Find the transistor which switches power and look for the ATmega pin switching that transistor. We'll take care about the display later.
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 14, 2018, 07:45:30 pm
I wonder if I might have damaged something. It turned out that pins of the transistor highlighted below were shorted by a bridge of solder. Now that I've removed the bridge, the tester only comes on if I press and hold the rotary encoder down. As soon as I release the rotary encoder, the tester turns off. Would this short-circuit between the base and collector of that transistor cause damage to another component (maybe that transistor itself)?

Yes, T1 could be damaged. The ATmega should be protected by the base resistor R8 (limiting current) and its internal clamping diodes.

Do you happen to know whether it can be replaced with any of the folloing three NPN transistors:

BO337-25
2N222 A 331
A42 B331

or will I need to get another 9014? Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 14, 2018, 07:49:05 pm
Any jelly bean NPN should work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 15, 2018, 12:35:38 am
Here is the sourcecode for U4's alternative firmware: https://github.com/atar-axis/tc1-u4
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 15, 2018, 05:25:00 pm
Any jelly bean NPN should work.

I removed the 9014 (the one closest to the LED at the top left) and it seems okay. Using a DMM diode test I get 0.7 V with positive electrode at base and negative electrode at either the collector or emitter. The DMM reads O.L. with the probes reversed.

When I connect power to the tester, it behaves the same way it did before I removed the transistor. If I press and hold the rotary encoder it comes on and switches off as soon as I release the encoder.

Does it seem less likely now that putting in a new transistor will fix the tester?

Edit: I inserted a BC237B and now it comes on when I press and release the rotary encoder but it ignores whatever components I connect and goes straight to a screen where it flashes "Vext=0mV". It then stays there without switching off and doesn't not respond to the rotary encoder. Should I try another transistor?
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEV2K on September 16, 2018, 12:16:26 am
The first thing to investigate is the power control circuitry. Find the transistor which switches power and look for the ATmega pin switching that transistor. We'll take care about the display later.

Power control is now working.  I remove the original backlight but didn't put anything back in its place.  So once I put an LED there, it works fine.  So right now, if I push the test button, it will stay on for 20 or 30 seconds, longer if I leave a component in the test socket.  What to do next?  Any suggestions on how to figure out why the LCD is not working?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gtx21 on September 16, 2018, 04:25:20 am
I'm replacing my TL-431 with the LM4040.

Edit: leaving this for history, but the diagram and comparison below is wrong as the data sheet view is bottom up. So don’t use this post.

Pinouts of LM4040 & TL-431:
(https://image.ibb.co/ft7wZz/4040_431_POn.jpg)

There is a post referenced as post #4052 in several thread replies which is supposed to be the correct layout on the AYAT PCB of the LM4040, but post #4052 doesn't have anything to do with this swap.  Post #4048 https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1306265/#msg1306279 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1306265/#msg1306279) however has a picture, which if I take to be the "old post #4052" and assume to be correct,  contradicts the pinouts above.  (Note that the - and + on the LM4040 are oddly labeled and are not the traditional - and + of the Anode and Cathode of a Diode (which they conveniently drew for us)).

To me, it looks like it should go as:

TL431LM4040
Pin 1 (Ref)Pin 3 (NC)
Pin 2 (Anode)Pin 1 ("-", Anode of Diode)
Pin 3 (Cathode)Pin 2 ("+",Cathode of Diode)

Here is the picture @Pepe10000 posted:
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=352820;image)


Am I reading things wrong and if so, how?
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on September 16, 2018, 09:48:58 am
Hi.

Watch this:

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 16, 2018, 10:50:08 am
Edit: I inserted a BC237B and now it comes on when I press and release the rotary encoder but it ignores whatever components I connect and goes straight to a screen where it flashes "Vext=0mV". It then stays there without switching off and doesn't not respond to the rotary encoder. Should I try another transistor?

Maybe a problem with the rotary encoder?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 16, 2018, 11:17:25 am
Power control is now working.  I remove the original backlight but didn't put anything back in its place.  So once I put an LED there, it works fine.  So right now, if I push the test button, it will stay on for 20 or 30 seconds, longer if I leave a component in the test socket.  What to do next?  Any suggestions on how to figure out why the LCD is not working?

Interesting! That clone uses the backlight LED instead of the dedicated indicator LED. The most common problem with displays is the pin assignment. I'd guess that you have double-checked all signal lines already. If you have a scope/DSO please check all signals at the display. Do SCLK and SDIN look correct? The idea is to verify that the level shifting is working fine. In case the signals aren't clean try to lower the value of the resistors. IIRC, Karl-Heinz suggests 2k7 in his documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gtx21 on September 17, 2018, 12:46:27 am
Hi.

Watch this:
 
Actually, that’s opposite of the data sheet I have.

http://www.ti.com/lit/ds/symlink/lm4040-n.pdf (http://www.ti.com/lit/ds/symlink/lm4040-n.pdf)

Edit: Holy crap!  I’m glad I asked.  I see it now. Bottom up! Thanks @pepe10000!
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEV2K on September 17, 2018, 10:09:32 pm
The most common problem with displays is the pin assignment. I'd guess that you have double-checked all signal lines already. If you have a scope/DSO please check all signals at the display. Do SCLK and SDIN look correct? The idea is to verify that the level shifting is working fine. In case the signals aren't clean try to lower the value of the resistors. IIRC, Karl-Heinz suggests 2k7 in his documentation.

Thank you.  I got the LCD working.  It turns out that SCLK pin got loose with all the plugging and unplugging during testing.  I re-solder it and now there is something on the LCD screen.  Contrast 66 was too high for my setup, 33 is too low, 55 seems to be about right.  I didn't test the contrast setting further.  The "m" in v1.33m is missing some dots on the right side but the "m" in "Component Tester" is displayed correctly.  I am not sure if suggest there are still problems with display or not.

With a MAX232CP based serial port, a LM317 based 5V to 3V DC-DC converter, and a red led where the backlight used to be, it uses 41mA without back light and about 51mA with backlight when it is on but not actually testing anything.  Is this about right?

I am going to add some relay to discharge capacitors before testing similar to figure 2.3 of "TransistorTester with AVR microcontroller and a little more Version 1.13k".  Based on the posts here, it seems to be a good feature to have.  My question are, does it have to be a mechanical relay or can it be a CMOS analog switch like DG202/DG212.  These RDS(on) of 115ohm.  Would they make it impossible to measure low resistance resistors or ESR on inductors and capacitors?  Another thing is would CMOS analog switch itself be susceptible to residual voltage in capacitor?  How high is the residual voltage on a capacitor?  Is the voltage depending on the voltage that was initially applied to the capacitor to charge it or is it something intrinsic to the capacitor?  DG202/212 can operate between 4.5V to 18V and absolute max is 44V.  Why does section 2.2.1 page 11 says "A complete protection is not possible," is it referring to Figure 2.2a, Figure 2.3, or both?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on September 18, 2018, 03:37:01 am
I am going to add some relay to discharge capacitors before testing similar to figure 2.3 of "TransistorTester with AVR microcontroller and a little more Version 1.13k".  Based on the posts here, it seems to be a good feature to have.  My question are, does it have to be a mechanical relay or can it be a CMOS analog switch like DG202/DG212.  These RDS(on) of 115ohm.  Would they make it impossible to measure low resistance resistors or ESR on inductors and capacitors?  Another thing is would CMOS analog switch itself be susceptible to residual voltage in capacitor?  How high is the residual voltage on a capacitor?  Is the voltage depending on the voltage that was initially applied to the capacitor to charge it or is it something intrinsic to the capacitor?  DG202/212 can operate between 4.5V to 18V and absolute max is 44V.  Why does section 2.2.1 page 11 says "A complete protection is not possible," is it referring to Figure 2.2a, Figure 2.3, or both?

The residual voltage is the charge (voltage) stored across the capacitor after the source charging it is shutdown or removed (when not being powered or disconnected from circuit).  So this can be up to the rated voltage of the capacitor, which for most capacitors over 10V up to typically 1,000V or more are a problem for the tester electronics and any minor protection circuits.

A cmos switch will no work (RDSon and peak voltage) as you suggested might be a problem,

It is best to learn the habit of always discharging a capacitor before testing it with the transistor tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 18, 2018, 10:30:34 am
The "m" in v1.33m is missing some dots on the right side but the "m" in "Component Tester" is displayed correctly.  I am not sure if suggest there are still problems with display or not.

That's most likely a timing or signal issue.

With a MAX232CP based serial port, a LM317 based 5V to 3V DC-DC converter, and a red led where the backlight used to be, it uses 41mA without back light and about 51mA with backlight when it is on but not actually testing anything.  Is this about right?

Seems to be in the ballpark.

I am going to add some relay to discharge capacitors before testing similar to figure 2.3 of "TransistorTester with AVR microcontroller and a little more Version 1.13k".  Based on the posts here, it seems to be a good feature to have.  My question are, does it have to be a mechanical relay or can it be a CMOS analog switch like DG202/DG212.  These RDS(on) of 115ohm.  Would they make it impossible to measure low resistance resistors or ESR on inductors and capacitors?  Another thing is would CMOS analog switch itself be susceptible to residual voltage in capacitor?  How high is the residual voltage on a capacitor?  Is the voltage depending on the voltage that was initially applied to the capacitor to charge it or is it something intrinsic to the capacitor?  DG202/212 can operate between 4.5V to 18V and absolute max is 44V.  Why does section 2.2.1 page 11 says "A complete protection is not possible," is it referring to Figure 2.2a, Figure 2.3, or both?

Since a relay handles more current than a CMOS switch it's better to use the relay. The residual voltage you've mentioned is caused by an effect called "dielectric absorption" (https://en.wikipedia.org/wiki/Dielectric_absorption ), and for an electrolytic cap it can be 10-15% of the original voltage. Input protection was an afterthought for caps and resulted in the two simple circuit options which have some drawbacks. A proper input protection would require a complete redesign which would make the tester more complex and expensive. I'm a friend of discharging caps via a resistor before checking them with the tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on September 18, 2018, 06:15:05 pm
My AY-AT clone doesn't turn itself off if left alone for several minutes and also doesn't turn off if I try to switch it off manually. If I use the rotary encoder to self "switch off", the screen refreshes and the tester doesn't switch off. Does this suggest a fault? I hope to replace the microcontroller with one flashed with 1.33 (m-firmware) whilst it the one it came with is running 1.12.

Yes, there's something wrong with your tester. Please check the power control signal (ATmega328 PD6). It should change to low when powering off.

I've finally completed and boxed mine, and it turns off on long(ish) encoder press while displaying result. Two clicks on the encoder to the left enters the menu. 1.33m flashed.

I have some questions on this:

- First, is this the correct behaviour?
- I've read the ttester pdf and the menu options seem different. Kinda makes sense because different firmware, but what are the equivalents for "m" firmware?
- Shorting the probes for test does something but there is no indication to connect a capacitor. Is this correct?
- I didn't see the ESR result when measuring capacitors, so I tried the "ESR" entry in the menu. It does measure ESR, but the tester never turns off, neither by itself, nor by long press or anything else. I can't get out of it at all. Had to short the battery to turn it off (didn't want to unscrew the box open).
- What are the options "Adjustment", "Save" and "Load"?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 18, 2018, 06:38:02 pm
Yep, it's explained in the README file. And it will give you also the answers to your other questions. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on September 19, 2018, 04:36:32 am
Oh, found it. Didn't notice it before because it had no extension...

Thank you for this little toy, it is really useful. And thank you for forcing me to learn some AVR programming, although 10 years late  :P

For what it's worth, attached is my compiled firmware 1.33m for AY-AT clone with 20MHz crystal and LM4040. The resistors I used are only 1% though. Use it to check if yours works ok, but if you want better accuracy - you'll have to compile your own. The box is 3D printed from a Scrachi design on Thingiverse, only a little adjusted to expose SMD test pads.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on September 20, 2018, 07:11:08 am
amasing!
It looks like funny oldtimer or cute LEGO bricks  :-+

Sorry for my lasy ass (i didnt read all tread), but tel me please  whats the difference between this project vs original old german project vs china clones?

Thanx
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on September 20, 2018, 08:12:56 am
Well, from what I understand, our "Asian partners" don't release the source code of their gadgets, which is technically illegal (breaks GPL licence), and also very annoying when they change something and don't tell us. Plus the usual "luck of the draw" quality components which may be within the original spec one day, and "close enough" the next. Which is really sad in multiple ways, it's generally understood that they would sell more products to a bunch of industrious people with screwdrivers and sodlering irons if they would release absolutely everything. Not to mention free testing and feedback to continue improving things. ;)

It's the general consensus here that the clone marked "AY-AT" on the board is the closest to the original. Mine actually doesn't have it printed on there, but it looks right. There are other versions, some of which have added onto the original design, but alas - they aren't telling us what exactly has been changed and added software-wise, so most of us avoid those but some are determined to keep digging through the guts to figure out how it works.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 20, 2018, 10:55:40 am
Sorry for my lasy ass (i didnt read all tread), but tel me please  whats the difference between this project vs original old german project vs china clones?

Please read https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEV2K on September 21, 2018, 12:53:34 am
Since a relay handles more current than a CMOS switch it's better to use the relay. The residual voltage you've mentioned is caused by an effect called "dielectric absorption" (https://en.wikipedia.org/wiki/Dielectric_absorption ), and for an electrolytic cap it can be 10-15% of the original voltage. Input protection was an afterthought for caps and resulted in the two simple circuit options which have some drawbacks. A proper input protection would require a complete redesign which would make the tester more complex and expensive. I'm a friend of discharging caps via a resistor before checking them with the tester.

Thanks Azure and madires.  If I understand dielectric absorption correctly, let's say that I got a 330uF/200V electrolytic capacitor and I connected to a 5VDC.  15 minutes after the initial discharge, dielectric absorption causes a "reloaded" voltage of 5VDC*0.15=75mV.  Now I discharged it again, would I get another 75mV*0.15=11mV?  But let's say that I connect the same capacitor to 200VDC until it fully charges then discharge it.  15 minutes after discharge, I should get 200VDC*0.15=30V.  Now if I connect this to Component Tester without the relays, I have a good chance of killing the 328P, right?  On some microchips other than 328P, I see a spec for ESD protection, would ESD protection protect against this?  TTester chapter 5.3.1 says step 1 of capacitor measurement is discharging of capacitor if the voltage is below 1.3V.  So if the capacitor is 30V, then it will not get discharged and the Component Tester should say "CELL".  PC2 would remain input only and it is high impedance.  So if 328P dies, it did not die from having more than 40mA of current going through PC2 pin.  It died because PC2 pin cannot handle more than a voltage of Vcc+0.5V (page 364, Table 32-1 of datasheet), right?


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 21, 2018, 10:06:32 am
Any voltage higher than Vcc plus Vf of the pin's clamping diode can cause damage based on the current flowing. A low current is handled by the clamping diode (IIRC, 1mA for ATmega) but a larger current will damage the clamping diode, the I/O pin or even more. The protection relay and the TVS array are meant to take the larger part of the current of a charged cap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: flodo on September 21, 2018, 11:44:38 am
Just to let you know, yesterday the STC15W204S arrived, unfortunately they do NOT fit (as a replacement of U4).
The biggest problem is, that Pin 1 is not an INTerrupt (there are some other issues too... but most of them are super easy to fix by modifying the software).

The STC15W104S does fit, in fact - it is the one which STC recommends as a replacement of the STC15Lxxx series... I ordered some and will report back :)


Btw: v0.3.0: https://github.com/atar-axis/tc1-u4/releases
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 21, 2018, 04:49:11 pm
Edit: I inserted a BC237B and now it comes on when I press and release the rotary encoder but it ignores whatever components I connect and goes straight to a screen where it flashes "Vext=0mV". It then stays there without switching off and doesn't not respond to the rotary encoder. Should I try another transistor?

Maybe a problem with the rotary encoder?

The rotary encoder seems very difficult to remove even when trying with an SMD rework hot air gun. Is it possible to test it in-circuit or does it need to be removed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 21, 2018, 07:06:07 pm
You can check the rotary encoder in circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Azure on September 21, 2018, 11:11:06 pm
The rotary encoder seems very difficult to remove even when trying with an SMD rework hot air gun. Is it possible to test it in-circuit or does it need to be removed?

If you have not already tried one trick is to add some regular leaded PbSn solder (just solder on top of the current solder) to the pins before trying to remove them.  This mixes with the higher temp solder and the overall melting temp goes down and the part is easier to desolder/remove.
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEV2K on September 22, 2018, 01:17:33 am
Any voltage higher than Vcc plus Vf of the pin's clamping diode can cause damage based on the current flowing. A low current is handled by the clamping diode (IIRC, 1mA for ATmega) but a larger current will damage the clamping diode, the I/O pin or even more. The protection relay and the TVS array are meant to take the larger part of the current of a charged cap.

TVS, is this the SRV05-4 and P6KE6V8A that is in Figure 2.2b?

A question about reusing pins:  RC4 is currently connected to a 2.5V voltage reference, and RC5 measures  battery voltage via a 1:4 voltage divider, if I also want to use PC4 and PC5 for I2C_SDA and I2C_SCL respectively, would it be possible?   And similarly for PD2 and PD3 which I am currently using it as  LCD_SCLK and LCD_D/C respectively but I would like to dual use as KEY_INC and KEY_DEC but what modification do I need to make to the circuit?

I apologize if someone else already ask these question because I am pretty sure someone else did.  To prevent this from happening in the future, how do I search just within the topic "Re: $20 LCR ESR Transistor checker project"?
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEV2K on September 22, 2018, 03:45:38 am
I noticed that Markus' version can support up to 20MHz.  I am trying to decide whether I should unsolder 8MHz crystal and solder a 20MHz crystal in its place.  What is the benefit of having MCU clock running at 20MHz vs 8MHz?  Higher frequency generation and measurement.  I think both are currently limited at 1/4 MCU clock.  Faster PWM which is currently 1/1024 clock MCU.  But more power would be used, although probably only a small fraction of ~50mA it's currently using, am I right?  Would it measure components faster? What elese?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 22, 2018, 11:51:23 am
TVS, is this the SRV05-4 and P6KE6V8A that is in Figure 2.2b?

Yep!

A question about reusing pins:  RC4 is currently connected to a 2.5V voltage reference, and RC5 measures  battery voltage via a 1:4 voltage divider, if I also want to use PC4 and PC5 for I2C_SDA and I2C_SCL respectively, would it be possible?   And similarly for PD2 and PD3 which I am currently using it as  LCD_SCLK and LCD_D/C respectively but I would like to dual use as KEY_INC and KEY_DEC but what modification do I need to make to the circuit?

If you disable the battery monitoring (BAT_NONE), the external voltage reference and the protection relay (both are disabled by default) you can free up PC4 and PC5 for I2C. The increase/decrease push buttons are wired the same way like the rotary encoder (see Karl-Heinz' documentation for the rotary encoder).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 22, 2018, 12:01:38 pm
I noticed that Markus' version can support up to 20MHz.  I am trying to decide whether I should unsolder 8MHz crystal and solder a 20MHz crystal in its place.  What is the benefit of having MCU clock running at 20MHz vs 8MHz?  Higher frequency generation and measurement.  I think both are currently limited at 1/4 MCU clock.  Faster PWM which is currently 1/1024 clock MCU.  But more power would be used, although probably only a small fraction of ~50mA it's currently using, am I right?  Would it measure components faster? What elese?

Karl-Heinz's k-firmware supports also 20 MHz since a few months. Other benefits are faster display output and slightly better resolution for low value caps and inductors. And yes, you won't need a car battery. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEV2K on September 23, 2018, 06:06:41 am
A question about reusing pins:  RC4 is currently connected to a 2.5V voltage reference, and RC5 measures  battery voltage via a 1:4 voltage divider, if I also want to use PC4 and PC5 for I2C_SDA and I2C_SCL respectively, would it be possible?   And similarly for PD2 and PD3 which I am currently using it as  LCD_SCLK and LCD_D/C respectively but I would like to dual use as KEY_INC and KEY_DEC but what modification do I need to make to the circuit?

If you disable the battery monitoring (BAT_NONE), the external voltage reference and the protection relay (both are disabled by default) you can free up PC4 and PC5 for I2C. The increase/decrease push buttons are wired the same way like the rotary encoder (see Karl-Heinz' documentation for the rotary encoder).

I can move battery monitoring and external voltage reference to ADC6 and ADC7 so I can still keep the functions.  What about AREF?  Was there any reason I couldn't just move external voltage reference to AREF?
How would I use ADC6 and ADC7 or AREF?  Do I just change in config_328.h
Code: [Select]
#define TP_REF           PC4       /* test pin with 2.5V reference and relay */
#define TP_BAT           PC5       /* test pin with 4:1 voltage divider */
to
Code: [Select]
#define TP_REF           AREF      /* test pin with 2.5V reference and relay */
#define TP_BAT           ADC6      /* test pin with 4:1 voltage divider */
I haven't make up my mind about using relay or not.  I would probably have to keep 2.5V reference voltage at PC4 if I want to use relay since ADC6, 7, and AREF are all input only.

The dual use of increase/decrease push buttons and LCD display, I don't understand how it would work.  Does LCD only need to communicate with the 328P when we try to change what is being displayed or does it communicate every times it refreshes?  I can see noises on the Nokia 5110 (PCD8544) that is why I think there is some kind of refresh rate.  Right now PD2 is connected to LCD_SCLK, but if you look at Table 2.1 and 2.7, the rotary encoders are not connected to LCD_SCLK but instead to other LCD pins.  (I think Table 2.2 which has rotary encoder 1 connected to ST7565 STRIP_GRID is behaves completely differently, right?)  Do I need to move PD2 to some other LCD pin such as LCD_DN(MOSI)?  Another reason I ask is because I have the SCE pin on the LCD tied to the GND, so the LCD is enabled all the time.  Doesn't this means that any voltage change on PD2 and PD3 is going to affect the LCD? PD2 and PD3 are currently connected to 10K resistors then to LCD pins, following Figure 2.6 I would need to connect PD2 and PD3 via 10K resistors to 5V.  This probably means I need to
Code: [Select]
5V--10K--|
PD--1K---|--<10K--LCD
         |--PUSH_BUTTON--GND
PCD8544 's LCD_Data() calls SPI's SPI_Write_Byte() (bitbang version).  And in there it sends data to LCD by calling
Code: [Select]
SPI_PORT |= (1 << SPI_MOSI);
SPI_PORT &= ~(1 << SPI_MOSI);
which sets PD to either 5V or GND.  LCD would see 5V when PD=1 and 0.4V when PD=0, so I think above circuit would work.  But what about the problems I discussed earlier:
1) does LCD needs SPI communication all the time?
2) does the pushing the button affect subsequent SPI communication?
3) does the firmware need to query the button and communicate via SPI at the same time?  I think long push is only for the Test button not increase/decrease button.
4) do I need to move PD2 from LCD_SCLK to say LCD_DN(MOSI) keep in mind that SCE of PCD8544 is always connected to GND?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 23, 2018, 11:28:42 am
You can't re-purpose AREF because it's part of the ADC. You either add a buffer cap for the internal voltage references (Vcc and 1.1V) or feed an external reference voltage which will render the internal ones useless. And the tester is designed to use the internal voltage references for the ADC.

Sharing I/O pins between display and rotary encoder usually requires the display's /CS to prevent the display to interpret input from the rotary encoder as data. By selecting the shared lines carefully it can work with a fixed /CS tied to ground. When the firmware reads the rotary encoder it changes the I/O pins from output mode (for the display) to input mode, and back again afterwards. The SPI bus is only active when data is sent to the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEV2K on September 24, 2018, 05:41:16 am
Sharing I/O pins between display and rotary encoder usually requires the display's /CS to prevent the display to interpret input from the rotary encoder as data. By selecting the shared lines carefully it can work with a fixed /CS tied to ground. When the firmware reads the rotary encoder it changes the I/O pins from output mode (for the display) to input mode, and back again afterwards. The SPI bus is only active when data is sent to the display.

On first attempt, I can't get inc and dec buttons to share the same I/O pins as the LCD_D/C and DN(MOSI) without interfering with the display.  I'll try it again next week.  If I can't get it to work, I was thinking about using PC3 and PC5 as inc and dec key.  I might end up using a single cell li-ion as battery and if that is the case, then I don't need Battery voltage.  Zener can go on ADC6 or ADC7.  No I2C anymore, can't fit it in.  I can't find anything similar to SRV05-4.  Is P6KE6V8A needed because..?  Don't know, I originally thought maybe it has a lower clamp voltage, but it seems the clamp voltage is still higher than 5V.  Why is P6KE6V8A and the 100nF capacitor needed?  Wouldn't the thyrector in SRV05 work just as well?  I can't find any relay with 3 throws or poles (forgot which) but I did find a relay with 2 ??.  So maybe I use it on TP1 and TP3 and leave TP2 without protection.
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEV2K on September 24, 2018, 05:49:29 am
A question about using AVRDude to program both flash memory and eeprom:

This is the command I am using.  AVRdude is from ArduinoIDE.
Code: [Select]
avrdude -CC:\Users\Demo\AppData\Local\Arduino15\packages\arduino\tools\avrdude\6.3.0-arduino9/etc/avrdude.conf -v -patmega328p -cstk500v1 -PCOM4 -b115200 -Uflash:w:ComponentTester.hex:i -U eeprom:w:ComponentTester.eep:i

Program is always successful but kind of slow.  Increasing baud rate from 19200 to 115200 doesn't seem to improve the speed very much.  The eeprom writing part is extremely slow even though it's only 760 bytes.   Is my syntax incorrect?  Here is the output of avrdude.  As you can see below, programming 760 bytes of eeprom takes 36.24 seconds.
Code: [Select]
avrdude: Version 6.3, compiled on Jan 17 2017 at 12:00:53
         Copyright (c) 2000-2005 Brian Dean, [url]http://www.bdmicro.com/[/url]
         Copyright (c) 2007-2014 Joerg Wunsch

         System wide configuration file is "C:\Users\Demo\AppData\Local\Arduino15\packages\arduino\tools\avrdude\6.3.0-arduino9/etc/avrdude.conf"

         Using Port                    : COM4
         Using Programmer              : stk500v1
         Overriding Baud Rate          : 115200
         AVR Part                      : ATmega328P
         Chip Erase delay              : 9000 us
         PAGEL                         : PD7
         BS2                           : PC2
         RESET disposition             : dedicated
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
           flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
           lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
           signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

         Programmer Type : STK500
         Description     : Atmel STK500 Version 1.x firmware
         Hardware Version: 2
         Firmware Version: 1.18
         Topcard         : Unknown
         Vtarget         : 0.0 V
         Varef           : 0.0 V
         Oscillator      : Off
         SCK period      : 0.1 us

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: safemode: hfuse reads as D9
avrdude: safemode: efuse reads as FD
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
         To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: reading input file "ComponentTester.hex"
avrdude: writing flash (27730 bytes):

Writing | ################################################## | 100% 18.20s

avrdude: 27730 bytes of flash written
avrdude: verifying flash memory against ComponentTester.hex:
avrdude: load data flash data from input file ComponentTester.hex:
avrdude: input file ComponentTester.hex contains 27730 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 9.34s

avrdude: verifying ...
avrdude: 27730 bytes of flash verified
avrdude: reading input file "ComponentTester.eep"
avrdude: writing eeprom (760 bytes):

Writing | ################################################## | 100% 36.24s

avrdude: 760 bytes of eeprom written
avrdude: verifying eeprom memory against ComponentTester.eep:
avrdude: load data eeprom data from input file ComponentTester.eep:
avrdude: input file ComponentTester.eep contains 760 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 2.07s

avrdude: verifying ...
avrdude: 760 bytes of eeprom verified

avrdude: safemode: hfuse reads as D9
avrdude: safemode: efuse reads as FD
avrdude: safemode: Fuses OK (E:FD, H:D9, L:F7)

avrdude done.  Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on September 24, 2018, 06:05:23 am
I'm no command line fan, so I use "AVRDUDESS", a GUI addon for AVRDUDE. And I program my processor on a separate board using AVRISP clone and SPI. I guess it takes longer to display the status then to program.

I've noticed that fuses are not set unless you set them separately. I thought Makefile would calculate them and do that, but no. Bug or a feature?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 24, 2018, 09:53:33 am
Is P6KE6V8A needed because..?  Don't know, I originally thought maybe it has a lower clamp voltage, but it seems the clamp voltage is still higher than 5V.  Why is P6KE6V8A and the 100nF capacitor needed?  Wouldn't the thyrector in SRV05 work just as well?  I can't find any relay with 3 throws or poles (forgot which) but I did find a relay with 2 ??.  So maybe I use it on TP1 and TP3 and leave TP2 without protection.

P6KE6V8A and the 100nF cap aren't required but help. The P6KE6V8A is able to handle a harder hit than the SRV05. And the relay needs just two throws (see Karl-Heinz' documentation).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 24, 2018, 10:00:30 am
I've noticed that fuses are not set unless you set them separately. I thought Makefile would calculate them and do that, but no. Bug or a feature?

In most cases the fuses have to be set just once (brand new ATmega). I don't see any benefit in setting the fuses to the same values again and again when programming a new firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on September 25, 2018, 04:55:10 pm
I've noticed that fuses are not set unless you set them separately. I thought Makefile would calculate them and do that, but no. Bug or a feature?

In most cases the fuses have to be set just once (brand new ATmega). I don't see any benefit in setting the fuses to the same values again and again when programming a new firmware.

I often say and write things without proper explanation. But it all sounded good in my head, I swear! :)

What I meant to say is: adjusting the values in appropriate files, then compiling, then uploading does NOT set the fuses to required values posted elsewhere in this thread (even with the checkbox "set fuses" checked). I had to set them manually after programming. Thinking about it now, it could be Avrdudess problem?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 28, 2018, 12:00:48 pm
Btw: v0.3.0: https://github.com/atar-axis/tc1-u4/releases
flodo,One of owners of LCR-TC1 has updated STC15L104W firmware your version 0.3.1. The tester works, but there is one problem. I will cite his words:
"After check of components not always correctly fulfills switching off. I have inserted, let us assume, the capacitor, I have checked it. The screen has gone out. I insert other component, I press the button, the screen with the message "Good bye" lights up at once and the tester "hangs". Doesn't react to the button. To have to open a tester and to switch-off the battery, otherwise it will be discharged in zero. Can after measurement on this message hang. And, the more on the battery, the glitch is more often than a charge."
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 28, 2018, 12:36:36 pm
What I meant to say is: adjusting the values in appropriate files, then compiling, then uploading does NOT set the fuses to required values posted elsewhere in this thread (even with the checkbox "set fuses" checked). I had to set them manually after programming. Thinking about it now, it could be Avrdudess problem?

Don't know, I don't use Avrdudess. If you are using make and avrdude it would be a simple "make fuses".
Title: Re: $20 LCR ESR Transistor checker project
Post by: seanspotatobusiness on September 29, 2018, 01:09:33 am
I removed my rotary encoder and determined that it may be defective by connecting the CLCK and DATA signals to 5 V via LEDs and suitable resistors. Only one of the signals produced a flashing LED when rotating the encoder. Is it true that water getting into an encoder can damage it? I did take care when cleaning flux from my board but I suppose it's possible that some water (70% isopropanol, 30% water) was able to ingress. What is the appropriate encoder to replace with? Does it matter how many steps it has per rotation? Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: EEV2K on September 29, 2018, 04:39:37 am
I'm no command line fan, so I use "AVRDUDESS", a GUI addon for AVRDUDE.

I tried it.  The program looks pretty good.  The speed is the same though.  At least this means my avrdude syntax is correct.  I wonder if there is a need to reprogram the EEPROM every time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz1 on September 29, 2018, 08:48:40 am
Hi
I know the answer I want will be somewhere in the 208 pages of this thread but I will ask anyway.

Where can I get "the best" version.  I would prefer assembled but a kit would be OK.
I just need a link.

Do the assembled versions need modification to replace zeners and high tolerance resistors etc?

Dazz
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 29, 2018, 10:37:03 am
I removed my rotary encoder and determined that it may be defective by connecting the CLCK and DATA signals to 5 V via LEDs and suitable resistors. Only one of the signals produced a flashing LED when rotating the encoder. Is it true that water getting into an encoder can damage it? I did take care when cleaning flux from my board but I suppose it's possible that some water (70% isopropanol, 30% water) was able to ingress. What is the appropriate encoder to replace with? Does it matter how many steps it has per rotation? Thanks!

ALPS EC11 series for example. The number of steps/detents and Gray code pulses per step can be adjusted in the firmware. BTW, the rotary encoder has two switches creating Gray code pulse sequences.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 29, 2018, 10:43:42 am
I tried it.  The program looks pretty good.  The speed is the same though.  At least this means my avrdude syntax is correct.  I wonder if there is a need to reprogram the EEPROM every time.

Yes, the EEPROM has to be programmed too (several values and texts).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 29, 2018, 10:46:56 am
I know the answer I want will be somewhere in the 208 pages of this thread but I will ask anyway.

Where can I get "the best" version.  I would prefer assembled but a kit would be OK.
I just need a link.

Do the assembled versions need modification to replace zeners and high tolerance resistors etc?

As always, you'll find the answer in the last 10 pages ;) AY-AT. It doesn't require a mod, but you can mod it if you like.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz1 on September 29, 2018, 11:36:46 am
Where can I get "the best" version.  I would prefer assembled but a kit would be OK.
I just need a link.

As always, you'll find the answer in the last 10 pages ;) AY-AT. It doesn't require a mod, but you can mod it if you like.

OK, I found this: https://www.aliexpress.com/item/DIY-KITS-Digital-Combo-Component-M8-Transistor-Tester-Capacitor-LCR-Diode-Capacitance-ESR-meter-PWM-Square/32796308934.html?spm=2114.10010108.addToWishlist.2.2c533056fKXo2D&gps-id=pcDetailFavMayLike&scm=1007.12873.83260.0&scm_id=1007.12873.83260.0&scm-url=1007.12873.83260.0&pvid=6f18a567-c4f9-47b2-a41a-86e340b8c138 (https://www.aliexpress.com/item/DIY-KITS-Digital-Combo-Component-M8-Transistor-Tester-Capacitor-LCR-Diode-Capacitance-ESR-meter-PWM-Square/32796308934.html?spm=2114.10010108.addToWishlist.2.2c533056fKXo2D&gps-id=pcDetailFavMayLike&scm=1007.12873.83260.0&scm_id=1007.12873.83260.0&scm-url=1007.12873.83260.0&pvid=6f18a567-c4f9-47b2-a41a-86e340b8c138)
 and
https://www.ebay.com/itm/GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM-Signal-Generator-DIY/152443029396?epid=577875436&hash=item237e500794:g:l3wAAOSw4A5YqU1i (https://www.ebay.com/itm/GM328-Transistor-Tester-Diode-Cap-ESR-Volt-Freq-Meter-PWM-Signal-Generator-DIY/152443029396?epid=577875436&hash=item237e500794:g:l3wAAOSw4A5YqU1i)
Title: Re: $20 LCR ESR Transistor checker project
Post by: David Maddison on September 29, 2018, 11:55:05 am
I am new to to updating the firmware of these units and all the information in this thread is a bit overwhelming. I have a "Transistor Tester" by Fish8840 with a date on the board 2014-07. I would be interested in updating the firmware of this and have a few questions and observations:

1) Firstly, is any firmware update worthwhile for this unit?
2) I would have to solder a header pin in but for the pins to be on the topside of the board they would be a mirror image and I would need separate leads rather than a ribbon cable.
3) I already have a USBASP 2.0 programmer by LC Technology.
4) Having made the physical connection between the PC, programmer and the tester, what exact software do I need and what is the precise procedure to follow for the upgrade.
5) I am running Windows.

Thanks so much in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on September 29, 2018, 04:59:51 pm
dazz1, they are the ones. Rotary encoder on lower left, 3 sets of screw terminals (2 on the bottom, 1 on top), SMD test pads to the right of the ZIF-socket. You can find them assembled on eBay too for a bit extra.

P.S. I laughed my ass off looking at the ZIF-socket. The original thing is made by TEXTOOL and they cost a bit in their heyday. These ones are "TFXTDOL" made in Chyna. So funny.  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: +Mikie on September 29, 2018, 05:17:44 pm
I am new to to updating the firmware of these units and all the information in this thread is a bit overwhelming. I have a "Transistor Tester" by Fish8840 with a date on the board 2014-07. I would be interested in updating the firmware of this and have a few questions and observations:

1) Firstly, is any firmware update worthwhile for this unit?
2) I would have to solder a header pin in but for the pins to be on the topside of the board they would be a mirror image and I would need separate leads rather than a ribbon cable.
3) I already have a USBASP 2.0 programmer by LC Technology.
4) Having made the physical connection between the PC, programmer and the tester, what exact software do I need and what is the precise procedure to follow for the upgrade.
5) I am running Windows.

Thanks so much in advance.

I'm nowhere near an "exspurt" on this, but I'll try:

1. I don't have that exact unit, but I gather that general consensus is that Chinese cloners will throw on any firmware that works and leave it at that, even after the original creators have improved and expanded on their work. So yes, in general, getting the latest firmware is worthwhile but not absolutely essential.
2. I thought of that too, but the board is too small to place a header anywhere, and there no tracks for it. In other words, there would be some wiring anyway. I tried just soldering the wires directly onto the pins but for whatever reason it didn't work, so I went with the minimal system board and programmed the processor on that and then replugged it into the tester. There are other ways, but I went this way: https://www.ebay.com.au/itm/DIY-ATmega328P-Development-Board-for-Arduino-UNO-R3-with-Arduino-bootloader-DA/162685904544?epid=2200425187&hash=item25e0d5e6a0%3Ag%3AfOcAAOSwG-1ZyHqf&LH_BIN=1 (https://www.ebay.com.au/itm/DIY-ATmega328P-Development-Board-for-Arduino-UNO-R3-with-Arduino-bootloader-DA/162685904544?epid=2200425187&hash=item25e0d5e6a0%3Ag%3AfOcAAOSwG-1ZyHqf&LH_BIN=1)
3. You will need it if you choose to flash the Atmega.
4. USB driver for the USBASP, AVRDUDE, AVR toolchain. AVRDUDESS is a GUI that's not essential but it helps.
5. So do I.

Edit: P.S. I found having a set of each of these is handy, and they are cheap.
https://www.ebay.com.au/itm/918D-40Pcs-10cm-Feale-To-Female-Silicone-Dupont-Wire-Jumper-Cable-Connector/192643083037?epid=19023282587&hash=item2cda6c2b1d%3Ag%3Ay8AAAOSwGeFbiWYM&LH_BIN=1 (https://www.ebay.com.au/itm/918D-40Pcs-10cm-Feale-To-Female-Silicone-Dupont-Wire-Jumper-Cable-Connector/192643083037?epid=19023282587&hash=item2cda6c2b1d%3Ag%3Ay8AAAOSwGeFbiWYM&LH_BIN=1)
https://www.ebay.com.au/itm/9EFC-40Pcs-10cm-Feale-To-Female-Silicone-Dupont-Wire-Jumper-Cable-Connector/202421939322?epid=18023286796&hash=item2f2149ac7a%3Ag%3Aag8AAOSwHXtbieNh&LH_BIN=1 (https://www.ebay.com.au/itm/9EFC-40Pcs-10cm-Feale-To-Female-Silicone-Dupont-Wire-Jumper-Cable-Connector/202421939322?epid=18023286796&hash=item2f2149ac7a%3Ag%3Aag8AAOSwHXtbieNh&LH_BIN=1)
Title: Re: $20 LCR ESR Transistor checker project
Post by: David Maddison on September 30, 2018, 10:05:27 am
Thanks Mikie.

Note that I am in this at a very basic level. All I want to do is update the firmware in my FISH8840 device and am not interested in the numerous modifications discussed.

I have spent a lot more time into looking at this and have also downloaded and installed AVRDUDESS.

I have bought the header extension leads. I already have some header pins.

From my understanding I download from either the directory mega328_fish8840 or mega328_fish8840_OC at https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)

I do not know from which directory to download. What is the difference? My unit has a 128x64 graphical display, an 8MHz crystal and a Mega328P.

Do I download the EEP and HEX files and point to their location from within AVRDUDESS?

Also I am not sure about the settings in ARDUDESS such as baud rate and bit clock and the fuse lock bits. Is there any other options I need to know about?

Again, many thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on September 30, 2018, 05:42:41 pm
Hi,
got this one from local shop, thought it was the T3 / T4 variant so went ahead and tried to flash new firmware on it
got firmware from "https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_T3_T4_st7565"

flash log
Code: [Select]
PS D:\Documents\Desktop\T3> avrdude.exe -c arduino -b 19200 -p m328p -P COM4 -U flash:w:TransistorTester.hex:a -U eeprom:w:TransistorTester.eep:
a -v

avrdude.exe: Version 6.0.1, compiled on Apr 15 2015 at 19:59:58
             Copyright (c) 2000-2005 Brian Dean, [url]http://www.bdmicro.com/[/url]
             Copyright (c) 2007-2009 Joerg Wunsch

             System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf"

             Using Port                    : COM4
             Using Programmer              : arduino
             Overriding Baud Rate          : 19200
             AVR Part                      : ATmega328P
             Chip Erase delay              : 9000 us
             PAGEL                         : PD7
             BS2                           : PC2
             RESET disposition             : dedicated
             RETRY pulse                   : SCK
             serial program mode           : yes
             parallel program mode         : yes
             Timeout                       : 200
             StabDelay                     : 100
             CmdexeDelay                   : 25
             SyncLoops                     : 32
             ByteDelay                     : 0
             PollIndex                     : 3
             PollValue                     : 0x53
             Memory Detail                 :

                                      Block Poll               Page                       Polled
               Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
               ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
               eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
               flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
               lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
               signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

             Programmer Type : Arduino
             Description     : Arduino
             Hardware Version: 2
             Firmware Version: 1.18
             Topcard         : Unknown
             Vtarget         : 0.0 V
             Varef           : 0.0 V
             Oscillator      : Off
             SCK period      : 0.1 us

avrdude.exe: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

avrdude.exe: Device signature = 0x1e950f
avrdude.exe: safemode: lfuse reads as F7
avrdude.exe: safemode: hfuse reads as D9
avrdude.exe: safemode: efuse reads as 5
avrdude.exe: NOTE: "flash" memory has been specified, an erase cycle will be performed
             To disable this feature, specify the -D option.
avrdude.exe: erasing chip
avrdude.exe: reading input file "TransistorTester.hex"
avrdude.exe: input file TransistorTester.hex auto detected as raw binary
avrdude.exe: writing flash (32768 bytes):

Writing | ################################################## | 100% 36.35s

avrdude.exe: 32768 bytes of flash written
avrdude.exe: verifying flash memory against TransistorTester.hex:
avrdude.exe: load data flash data from input file TransistorTester.hex:
avrdude.exe: input file TransistorTester.hex auto detected as raw binary
avrdude.exe: input file TransistorTester.hex contains 32768 bytes
avrdude.exe: reading on-chip flash data:

Reading | ################################################## | 100% 20.67s

avrdude.exe: verifying ...
avrdude.exe: verification error, first mismatch at byte 0x0000
             0x00 != 0x0a
avrdude.exe: verification error; content mismatch

avrdude.exe: safemode: lfuse reads as 0
avrdude.exe: safemode: hfuse reads as 0
avrdude.exe: safemode: efuse reads as 0
avrdude.exe: safemode: lfuse changed! Was f7, and is now 0
Would you like this fuse to be changed back? [y/n] y
PS D:\Documents\Desktop\T3> avrdude.exe -c arduino -b 19200 -p m328p -P COM4 -U flash:w:TransistorTester.hex:a -U eeprom:w:TransistorTester.eep:
a -v

avrdude.exe: Version 6.0.1, compiled on Apr 15 2015 at 19:59:58
             Copyright (c) 2000-2005 Brian Dean, [url]http://www.bdmicro.com/[/url]
             Copyright (c) 2007-2009 Joerg Wunsch

             System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf"

             Using Port                    : COM4
             Using Programmer              : arduino
             Overriding Baud Rate          : 19200
             AVR Part                      : ATmega328P
             Chip Erase delay              : 9000 us
             PAGEL                         : PD7
             BS2                           : PC2
             RESET disposition             : dedicated
             RETRY pulse                   : SCK
             serial program mode           : yes
             parallel program mode         : yes
             Timeout                       : 200
             StabDelay                     : 100
             CmdexeDelay                   : 25
             SyncLoops                     : 32
             ByteDelay                     : 0
             PollIndex                     : 3
             PollValue                     : 0x53
             Memory Detail                 :

                                      Block Poll               Page                       Polled
               Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
               ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
               eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
               flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
               lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
               signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

             Programmer Type : Arduino
             Description     : Arduino
             Hardware Version: 2
             Firmware Version: 1.18
             Topcard         : Unknown
             Vtarget         : 0.0 V
             Varef           : 0.0 V
             Oscillator      : Off
             SCK period      : 0.1 us

avrdude.exe: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

avrdude.exe: Device signature = 0x1e950f
avrdude.exe: safemode: lfuse reads as 1F
avrdude.exe: safemode: hfuse reads as D9
avrdude.exe: safemode: efuse reads as 5
avrdude.exe: NOTE: "flash" memory has been specified, an erase cycle will be performed
             To disable this feature, specify the -D option.
avrdude.exe: erasing chip
avrdude.exe: reading input file "TransistorTester.hex"
avrdude.exe: input file TransistorTester.hex auto detected as raw binary
avrdude.exe: writing flash (32768 bytes):

Writing | ################################################## | 100% 36.39s

avrdude.exe: 32768 bytes of flash written
avrdude.exe: verifying flash memory against TransistorTester.hex:
avrdude.exe: load data flash data from input file TransistorTester.hex:
avrdude.exe: input file TransistorTester.hex auto detected as raw binary
avrdude.exe: input file TransistorTester.hex contains 32768 bytes
avrdude.exe: reading on-chip flash data:

Reading | ################################################## | 100% 20.56s

avrdude.exe: verifying ...
avrdude.exe: 32768 bytes of flash verified
avrdude.exe: reading input file "TransistorTester.eep"
avrdude.exe: input file TransistorTester.eep auto detected as raw binary
avrdude.exe: writing eeprom (1024 bytes):

Writing | ################################################## | 100% 49.98s

avrdude.exe: 1024 bytes of eeprom written
avrdude.exe: verifying eeprom memory against TransistorTester.eep:
avrdude.exe: load data eeprom data from input file TransistorTester.eep:
avrdude.exe: input file TransistorTester.eep auto detected as raw binary
avrdude.exe: input file TransistorTester.eep contains 1024 bytes
avrdude.exe: reading on-chip eeprom data:

Reading | ################################################## | 100% 3.88s

avrdude.exe: verifying ...
avrdude.exe: 1024 bytes of eeprom verified

avrdude.exe: safemode: lfuse reads as 1F
avrdude.exe: safemode: hfuse reads as D9
avrdude.exe: safemode: efuse reads as 5
avrdude.exe: safemode: Fuses OK (H:05, E:D9, L:1F)

avrdude.exe done.  Thank you.

PS D:\Documents\Desktop\T3> avrdude.exe -c arduino -b 19200 -p m328p -P COM4 -U flash:w:TransistorTester.hex:a -U eeprom:w:TransistorTester.eep:
a -v

avrdude.exe: Version 6.0.1, compiled on Apr 15 2015 at 19:59:58
             Copyright (c) 2000-2005 Brian Dean, [url]http://www.bdmicro.com/[/url]
             Copyright (c) 2007-2009 Joerg Wunsch

             System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf"

             Using Port                    : COM4
             Using Programmer              : arduino
             Overriding Baud Rate          : 19200
             AVR Part                      : ATmega328P
             Chip Erase delay              : 9000 us
             PAGEL                         : PD7
             BS2                           : PC2
             RESET disposition             : dedicated
             RETRY pulse                   : SCK
             serial program mode           : yes
             parallel program mode         : yes
             Timeout                       : 200
             StabDelay                     : 100
             CmdexeDelay                   : 25
             SyncLoops                     : 32
             ByteDelay                     : 0
             PollIndex                     : 3
             PollValue                     : 0x53
             Memory Detail                 :

                                      Block Poll               Page                       Polled
               Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
               ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
               eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
               flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
               lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
               calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
               signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

             Programmer Type : Arduino
             Description     : Arduino
             Hardware Version: 2
             Firmware Version: 1.18
             Topcard         : Unknown
             Vtarget         : 0.0 V
             Varef           : 0.0 V
             Oscillator      : Off
             SCK period      : 0.1 us

avrdude.exe: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

avrdude.exe: Device signature = 0x1e950f
avrdude.exe: safemode: lfuse reads as 1F
avrdude.exe: safemode: hfuse reads as D9
avrdude.exe: safemode: efuse reads as 5
avrdude.exe: NOTE: "flash" memory has been specified, an erase cycle will be performed
             To disable this feature, specify the -D option.
avrdude.exe: erasing chip
avrdude.exe: reading input file "TransistorTester.hex"
avrdude.exe: input file TransistorTester.hex auto detected as raw binary
avrdude.exe: writing flash (32768 bytes):

Writing | ################################################## | 100% 36.39s

avrdude.exe: 32768 bytes of flash written
avrdude.exe: verifying flash memory against TransistorTester.hex:
avrdude.exe: load data flash data from input file TransistorTester.hex:
avrdude.exe: input file TransistorTester.hex auto detected as raw binary
avrdude.exe: input file TransistorTester.hex contains 32768 bytes
avrdude.exe: reading on-chip flash data:

Reading | ################################################## | 100% 20.65s

avrdude.exe: verifying ...
avrdude.exe: 32768 bytes of flash verified
avrdude.exe: reading input file "TransistorTester.eep"
avrdude.exe: input file TransistorTester.eep auto detected as raw binary
avrdude.exe: writing eeprom (1024 bytes):

Writing | ################################################## | 100% 50.00s

avrdude.exe: 1024 bytes of eeprom written
avrdude.exe: verifying eeprom memory against TransistorTester.eep:
avrdude.exe: load data eeprom data from input file TransistorTester.eep:
avrdude.exe: input file TransistorTester.eep auto detected as raw binary
avrdude.exe: input file TransistorTester.eep contains 1024 bytes
avrdude.exe: reading on-chip eeprom data:

Reading | ################################################## | 100% 3.79s

avrdude.exe: verifying ...
avrdude.exe: 1024 bytes of eeprom verified

avrdude.exe: safemode: lfuse reads as 1F
avrdude.exe: safemode: hfuse reads as D9
avrdude.exe: safemode: efuse reads as 5
avrdude.exe: safemode: Fuses OK (H:05, E:D9, L:1F)

avrdude.exe done.  Thank you.






after flashing, when i press the test button, the backligh does not turn, the screen displays black for a sec and then off.

Does anyone know which variant is this one and the proper firmware for it?

Edit/PS: forgot to mention that the ISP header on this one is not mirrored as opposed to T3/T4
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 01, 2018, 05:40:42 am
daemon123, use for this device an firmware from the folder "mega328_T4_v2_st7565"
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on October 03, 2018, 01:51:54 pm
Can I purchase a ready made transistor tester running firmware 1.13m where the RxD and TxD ports are readily accessible? I am planning to do some software for the TT and do not want to spend time assembling it or even compiling the firmware for it. The latter being a bit beyond me anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mgerges on October 03, 2018, 05:52:35 pm
Hello,

Sorry if it's a repeated question, just search didn't return an answer.

I bought one with FW 1.13 and it has some additional features
- IR encode / decode
- DHT11 / DS11B20

I loaded 1.13 from mikrocontroller.net but it doesn't have those features. I checked the code, but no traces of those testing abilities. So, Where is the firmware which has those features as well ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2018, 06:38:49 pm
Can I purchase a ready made transistor tester running firmware 1.13m where the RxD and TxD ports are readily accessible? I am planning to do some software for the TT and do not want to spend time assembling it or even compiling the firmware for it. The latter being a bit beyond me anyway.

Unfortunately not. So you need to modify one of the clones. If you need help with the firmware please PM me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2018, 06:49:13 pm
I bought one with FW 1.13 and it has some additional features
- IR encode / decode
- DHT11 / DS11B20

I loaded 1.13 from mikrocontroller.net but it doesn't have those features. I checked the code, but no traces of those testing abilities. So, Where is the firmware which has those features as well ?

That clone has a modified firmware. The m-firmware supports the IR receiver and an IR sender (more than 10 different protocols). The next version will also support the DS11B20 OneWire temperature sensor. There are no plans for the DHT11 yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on October 04, 2018, 09:46:52 am

So you need to modify one of the clones. If you need help with the firmware please PM me.

OK. So I'm planning to go the ATmega 644 route with no frills at all just to get my PC programming going.
See attached circuit stripped down from the excellent manual. Comments welcome.
Thanks for the firmware offer. Will PM you for the firmware as soon as I have my no frills circuit ready.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 04, 2018, 12:03:28 pm
A test push button with a pull-up resistor is strongly recommended. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mgerges on October 04, 2018, 10:51:44 pm
I bought one with FW 1.13 and it has some additional features
- IR encode / decode
- DHT11 / DS11B20

I loaded 1.13 from mikrocontroller.net but it doesn't have those features. I checked the code, but no traces of those testing abilities. So, Where is the firmware which has those features as well ?

That clone has a modified firmware. The m-firmware supports the IR receiver and an IR sender (more than 10 different protocols). The next version will also support the DS11B20 OneWire temperature sensor. There are no plans for the DHT11 yet.

Thanks for your response.

I noticed today the IR in m-FW, should I import it's code or go ahead with the m-FW? OR where is the list of differences, if any?
By saying next version, what do you mean? I already compiled from trunk (1.1.3k) but no traces of "DS11B20" in part_defs.h or the function_menu.c
When you say "no plans", where is the road map posted? Is there additional code repository rather than github & svn?

It is really frustrating, those sellers, who are selling an open-SW/HW and think few lines of code they added should not be shared as a secret  >:( >:(
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on October 05, 2018, 12:12:30 am
It is really frustrating, those sellers, who are selling an open-SW/HW and think few lines of code they added should not be shared as a secret  >:( >:(

Yeah, imagine how the original OS authors must feel. :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 05, 2018, 01:04:54 pm
I noticed today the IR in m-FW, should I import it's code or go ahead with the m-FW? OR where is the list of differences, if any?
By saying next version, what do you mean? I already compiled from trunk (1.1.3k) but no traces of "DS11B20" in part_defs.h or the function_menu.c

There are two firmware flavours. One is Karl-Heinz' k-firmware (current trunk version 1.13k) and the other one is the m-firmware (1.33m). The m-firmware's README file includes a brief overview of the differences to the k-firmware. At the moment, only the m-firmware supports an IR receiver/decoder and sender. The next version (1.34m) will support the DS11B20 OneWIre sensor. The code for that is written already and I'm working on a cap leakage check right now.

When you say "no plans", where is the road map posted? Is there additional code repository rather than github & svn?

It's just my private to-do list. No, the main repo is the svn at mikrocontroller.net.

It is really frustrating, those sellers, who are selling an open-SW/HW and think few lines of code they added should not be shared as a secret  >:( >:(

We've added a hint to the project's webpage about sharing mods but haven't received any feedback so far. Yep, it's sad. Seems to be Chinese culture.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 07, 2018, 10:35:15 am
Get your ISP programmer ready! ;)

1.34m:
- Added leakage check for capacitors.
- Changed default value for RH_OFFSET to 350 Ohms.
- Fixed missing menu entry for fixed IR receiver module.
- Polish texts (thanks to Szpila).
- Display driver for output via VT100 serial terminal.
- Support for temperature sensor DS18B20.
- Driver for OneWire bus.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 07, 2018, 02:39:45 pm
Get your ISP programmer ready! ;)
1.34m:
We will state separate thanks of madires for the updated Clones file with addition of new configurations for different clones! ;) :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 07, 2018, 09:14:15 pm
Greetings dear friends!
Help is needed. Tester M644 as in the message "Reply # 5017 on: August 17, 2018, 04:03:16 am". Does not work with firmware 1.33 or 1.34. More precisely, the tester works, but there is no display on the display. I tried different options in the file, nothing happened. Where was I wrong, why does SPI not work?
config_644.h
//#if 0
#define LCD_ST7565R
#define LCD_GRAPHIC                     /* graphic display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTB          /* port data register */
#define LCD_DDR          DDRB           /* port data direction register */
#define LCD_RESET        PB4            /* port pin used for /RES (optional) */
//#define LCD_CS           PB3            /* port pin used for /CS1 (optional) */
#define LCD_A0           PB5            /* port pin used for A0 */
#define LCD_SCL          PB6            /* port pin used for SCL */
#define LCD_SI           PB7            /* port pin used for SI (LCD's data input) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
//#define LCD_FLIP_X                      /* enable horizontal flip */
#define LCD_OFFSET_X                    /* enable x offset of 4 dots */
#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     8             /* default contrast (0-63) */
#define FONT_8X8_VF                     /* 8x8 font, vertically aligned & flipped */
#define SYMBOLS_24X24_VFP               /* 24x24 symbols, vertically aligned & flipped */
#define SPI_HARDWARE                    /* hardware SPI */
//#endif
.....
.....

/*
 *  test push button and power management
 */

#define CONTROL_PORT     PORTB     /* port data register */
#define CONTROL_DDR      DDRB      /* port data direction register */
#define CONTROL_PIN      PINB      /* port input pins register */
#define POWER_CTRL       PB1       /* controls power (1: on / 0: off) */
#define TEST_BUTTON      PC7       /* test/start push button (low active) */


/*
 *  rotary encoder
 */

#define ENCODER_PORT     PORTB     /* port data register */
#define ENCODER_DDR      DDRB      /* port data direction register */
#define ENCODER_PIN      PINB      /* port input pins register */
#define ENCODER_A        PB5       /* rotary encoder A signal */
#define ENCODER_B        PB7       /* rotary encoder B signal */
 |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on October 07, 2018, 09:14:54 pm
While maybe slightly off topic I'm posting this here hoping it might help someone else.
I've mentioned before that I have used a Attiny44 USBTinyISP programmer to read the firmware from a transistor tester (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1387441/#msg1387441).
Normally I just use my GQ-4X external programmer but this time I wanted to try the Attiny44 again.
But no matter what I did it would always crash avrdude when I tried to read the eeprom.
And writing the eeprom would fail.
Finally after spending waaaay too much time troubleshooting this, looking for updated firmware for the Attiny44 that just went to a very deep rabbit hole.
It finally dawned on me: The tester I successfully read has a 8Mhz clock, the one I'm trying to read has a 16Mhz clock.
Then I need to use the "-B" parameter (bitclock) of avrdude to slow down the clock, a setting of "-B 68" solved my issue.
Soo much time spent on this, for no reason, I'd like to say you live and learn but here I don't think I want to publicly state what a learned: as children might be reading :D
Posting some of the failure messages for the Google bots:
Code: [Select]
avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (915 bytes):

Writing | ################################################## | 100% 225.75s

avrdude: 915 bytes of eeprom written
avrdude: verifying eeprom memory against TransistorTester.eep:
avrdude: load data eeprom data from input file TransistorTester.eep:
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: input file TransistorTester.eep contains 915 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 27.96s

avrdude: verifying ...
avrdude: verification error, first mismatch at byte 0x0000
         0x54 != 0x20
avrdude: verification error; content mismatch

avrdude: safemode: Fuses OK (E:FC, H:D9, L:F7)

avrdude done.  Thank you.

Code: [Select]
Faulting application name: avrdude.exe, version: 0.0.0.0, time stamp: 0x5ad5b1a5
Faulting module name: ntdll.dll, version: 6.1.7601.24231, time stamp: 0x5b6db230
Exception code: 0xc0000005
Fault offset: 0x0002e466
Faulting process id: 0x1594
Faulting application start time: 0x01d45e27c00cb5e2
Faulting application path: C:\Program Files (x86)\Arduino\hardware\tools\avr\bin\avrdude.exe
Faulting module path: C:\Windows\SysWOW64\ntdll.dll
Report Id: 10ef1420-ca1b-11e8-8288-d050995c3d4b

Code: [Select]
avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: reading eeprom memory:

Reading | ################################################## | 100% 17.15s

avrdude: writing output file "test2.eep"

avrdude: safemode: Fuses OK (E:FD, H:DE, L:FF)

avrdude done.  Thank you.

*** Error in `/root/avrdude/avrdude-6.3/avrdude': munmap_chunk(): invalid pointer: 0x00000000010ed2c0 ***
======= Backtrace: =========
/lib64/libc.so.6(+0x7ab54)[0x7f3fe3775b54]
/root/avrdude/avrdude-6.3/avrdude[0x409eee]
/root/avrdude/avrdude-6.3/avrdude[0x40900c]
/root/avrdude/avrdude-6.3/avrdude[0x409eee]
/root/avrdude/avrdude-6.3/avrdude[0x409545]
/lib64/libc.so.6(+0x38a69)[0x7f3fe3733a69]
/lib64/libc.so.6(+0x38ab5)[0x7f3fe3733ab5]
/lib64/libc.so.6(__libc_start_main+0xfc)[0x7f3fe371cc0c]
/root/avrdude/avrdude-6.3/avrdude[0x404c2f]
======= Memory map: ========
00400000-00465000 r-xp 00000000 fd:01 5384907                            /root/avrdude/avrdude-6.3/avrdude
00664000-00665000 r--p 00064000 fd:01 5384907                            /root/avrdude/avrdude-6.3/avrdude
00665000-00666000 rw-p 00065000 fd:01 5384907                            /root/avrdude/avrdude-6.3/avrdude
00666000-0066c000 rw-p 00000000 00:00 0
00e05000-0111e000 rw-p 00000000 00:00 0                                  [heap]
7f3fe1a23000-7f3fe1a24000 ---p 00000000 00:00 0
7f3fe1a24000-7f3fe2224000 rw-p 00000000 00:00 0
7f3fe2224000-7f3fe2233000 r-xp 00000000 fd:01 525393                     /usr/lib64/libbz2.so.1.0.6
7f3fe2233000-7f3fe2432000 ---p 0000f000 fd:01 525393                     /usr/lib64/libbz2.so.1.0.6
7f3fe2432000-7f3fe2433000 r--p 0000e000 fd:01 525393                     /usr/lib64/libbz2.so.1.0.6
7f3fe2433000-7f3fe2434000 rw-p 0000f000 fd:01 525393                     /usr/lib64/libbz2.so.1.0.6
7f3fe2434000-7f3fe2459000 r-xp 00000000 fd:01 529319                     /usr/lib64/liblzma.so.5.2.2
7f3fe2459000-7f3fe2658000 ---p 00025000 fd:01 529319                     /usr/lib64/liblzma.so.5.2.2
7f3fe2658000-7f3fe2659000 r--p 00024000 fd:01 529319                     /usr/lib64/liblzma.so.5.2.2
7f3fe2659000-7f3fe265a000 rw-p 00025000 fd:01 529319                     /usr/lib64/liblzma.so.5.2.2
7f3fe265a000-7f3fe266f000 r-xp 00000000 fd:01 525296                     /usr/lib64/libz.so.1.2.7
7f3fe266f000-7f3fe286e000 ---p 00015000 fd:01 525296                     /usr/lib64/libz.so.1.2.7
7f3fe286e000-7f3fe286f000 r--p 00014000 fd:01 525296                     /usr/lib64/libz.so.1.2.7
7f3fe286f000-7f3fe2870000 rw-p 00015000 fd:01 525296                     /usr/lib64/libz.so.1.2.7
7f3fe2870000-7f3fe2887000 r-xp 00000000 fd:01 547457                     /usr/lib64/libelf-0.168.so
7f3fe2887000-7f3fe2a86000 ---p 00017000 fd:01 547457                     /usr/lib64/libelf-0.168.so
7f3fe2a86000-7f3fe2a87000 r--p 00016000 fd:01 547457                     /usr/lib64/libelf-0.168.so
7f3fe2a87000-7f3fe2a88000 rw-p 00017000 fd:01 547457                     /usr/lib64/libelf-0.168.so
7f3fe2a88000-7f3fe2a8c000 r-xp 00000000 fd:01 525459                     /usr/lib64/libattr.so.1.1.0
7f3fe2a8c000-7f3fe2c8b000 ---p 00004000 fd:01 525459                     /usr/lib64/libattr.so.1.1.0
7f3fe2c8b000-7f3fe2c8c000 r--p 00003000 fd:01 525459                     /usr/lib64/libattr.so.1.1.0
7f3fe2c8c000-7f3fe2c8d000 rw-p 00004000 fd:01 525459                     /usr/lib64/libattr.so.1.1.0
7f3fe2c8d000-7f3fe2ca2000 r-xp 00000000 fd:01 527792                     /usr/lib64/libgcc_s-4.8.5-20150702.so.1
7f3fe2ca2000-7f3fe2ea1000 ---p 00015000 fd:01 527792                     /usr/lib64/libgcc_s-4.8.5-20150702.so.1
7f3fe2ea1000-7f3fe2ea2000 r--p 00014000 fd:01 527792                     /usr/lib64/libgcc_s-4.8.5-20150702.so.1
7f3fe2ea2000-7f3fe2ea3000 rw-p 00015000 fd:01 527792                     /usr/lib64/libgcc_s-4.8.5-20150702.so.1
7f3fe2ea3000-7f3fe2ee7000 r-xp 00000000 fd:01 538866                     /usr/lib64/libdw-0.168.so
7f3fe2ee7000-7f3fe30e7000 ---p 00044000 fd:01 538866                     /usr/lib64/libdw-0.168.so
7f3fe30e7000-7f3fe30e9000 r--p 00044000 fd:01 538866                     /usr/lib64/libdw-0.168.so
7f3fe30e9000-7f3fe30ea000 rw-p 00046000 fd:01 538866                     /usr/lib64/libdw-0.168.so
7f3fe30ea000-7f3fe30ee000 r-xp 00000000 fd:01 525463                     /usr/lib64/libcap.so.2.22
7f3fe30ee000-7f3fe32ed000 ---p 00004000 fd:01 525463                     /usr/lib64/libcap.so.2.22
7f3fe32ed000-7f3fe32ee000 r--p 00003000 fd:01 525463                     /usr/lib64/libcap.so.2.22
7f3fe32ee000-7f3fe32ef000 rw-p 00004000 fd:01 525463                     /usr/lib64/libcap.so.2.22
7f3fe32ef000-7f3fe32f6000 r-xp 00000000 fd:01 531856                     /usr/lib64/librt-2.17.so
7f3fe32f6000-7f3fe34f5000 ---p 00007000 fd:01 531856                     /usr/lib64/librt-2.17.so
7f3fe34f5000-7f3fe34f6000 r--p 00006000 fd:01 531856                     /usr/lib64/librt-2.17.so
7f3fe34f6000-7f3fe34f7000 rw-p 00007000 fd:01 531856                     /usr/lib64/librt-2.17.so
7f3fe34f7000-7f3fe34f9000 r-xp 00000000 fd:01 529318                     /usr/lib64/libdl-2.17.so
7f3fe34f9000-7f3fe36f9000 ---p 00002000 fd:01 529318                     /usr/lib64/libdl-2.17.so
7f3fe36f9000-7f3fe36fa000 r--p 00002000 fd:01 529318                     /usr/lib64/libdl-2.17.so
7f3fe36fa000-7f3fe36fb000 rw-p 00003000 fd:01 529318                     /usr/lib64/libdl-2.17.so
7f3fe36fb000-7f3fe38b3000 r-xp 00000000 fd:01 529065                     /usr/lib64/libc-2.17.so
7f3fe38b3000-7f3fe3ab3000 ---p 001b8000 fd:01 529065                     /usr/lib64/libc-2.17.so
7f3fe3ab3000-7f3fe3ab7000 r--p 001b8000 fd:01 529065                     /usr/lib64/libc-2.17.so
7f3fe3ab7000-7f3fe3ab9000 rw-p 001bc000 fd:01 529065                     /usr/lib64/libc-2.17.so
7f3fe3ab9000-7f3fe3abe000 rw-p 00000000 00:00 0
7f3fe3abe000-7f3fe3ae3000 r-xp 00000000 fd:01 525209                     /usr/lib64/libtinfo.so.5.9
7f3fe3ae3000-7f3fe3ce3000 ---p 00025000 fd:01 525209                     /usr/lib64/libtinfo.so.5.9
7f3fe3ce3000-7f3fe3ce7000 r--p 00025000 fd:01 525209                     /usr/lib64/libtinfo.so.5.9
7f3fe3ce7000-7f3fe3ce8000 rw-p 00029000 fd:01 525209                     /usr/lib64/libtinfo.so.5.9
7f3fe3ce8000-7f3fe3d0e000 r-xp 00000000 fd:01 525199                     /usr/lib64/libncurses.so.5.9
7f3fe3d0e000-7f3fe3f0d000 ---p 00026000 fd:01 525199                     /usr/lib64/libncurses.so.5.9
7f3fe3f0d000-7f3fe3f0e000 r--p 00025000 fd:01 525199                     /usr/lib64/libncurses.so.5.9
7f3fe3f0e000-7f3fe3f0f000 rw-p 00026000 fd:01 525199                     /usr/lib64/libncurses.so.5.9
7f3fe3f0f000-7f3fe4010000 r-xp 00000000 fd:01 529329                     /usr/lib64/libm-2.17.so
7f3fe4010000-7f3fe420f000 ---p 00101000 fd:01 529329                     /usr/lib64/libm-2.17.so
7f3fe420f000-7f3fe4210000 r--p 00100000 fd:01 529329                     /usr/lib64/libm-2.17.so
7f3fe4210000-7f3fe4211000 rw-p 00101000 fd:01 529329                     /usr/lib64/libm-2.17.so
7f3fe4211000-7f3fe4228000 r-xp 00000000 fd:01 530227                     /usr/lib64/libpthread-2.17.so
7f3fe4228000-7f3fe4427000 ---p 00017000 fd:01 530227                     /usr/lib64/libpthread-2.17.so
7f3fe4427000-7f3fe4428000 r--p 00016000 fd:01 530227                     /usr/lib64/libpthread-2.17.so
7f3fe4428000-7f3fe4429000 rw-p 00017000 fd:01 530227                     /usr/lib64/libpthread-2.17.so
7f3fe4429000-7f3fe442d000 rw-p 00000000 00:00 0
7f3fe442d000-7f3fe443a000 r-xp 00000000 fd:01 527988                     /usr/lib64/libftdi1.so.2.1.0
7f3fe443a000-7f3fe4639000 ---p 0000d000 fd:01 527988                     /usr/lib64/libftdi1.so.2.1.0
7f3fe4639000-7f3fe463a000 r--p 0000c000 fd:01 527988                     /usr/lib64/libftdi1.so.2.1.0
7f3fe463a000-7f3fe463b000 rw-p 0000d000 fd:01 527988                     /usr/lib64/libftdi1.so.2.1.0
7f3fe463b000-7f3fe463f000 r-xp 00000000 fd:01 527986                     /usr/lib64/libusb-0.1.so.4.4.4
7f3fe463f000-7f3fe483f000 ---p 00004000 fd:01 527986                     /usr/lib64/libusb-0.1.so.4.4.4
7f3fe483f000-7f3fe4840000 r--p 00004000 fd:01 527986                     /usr/lib64/libusb-0.1.so.4.4.4
7f3fe4840000-7f3fe4841000 rw-p 00005000 fd:01 527986                     /usr/lib64/libusb-0.1.so.4.4.4
7f3fe4841000-7f3fe4858000 r-xp 00000000 fd:01 527664                     /usr/lib64/libusb-1.0.so.0.1.0
7f3fe4858000-7f3fe4a57000 ---p 00017000 fd:01 527664                     /usr/lib64/libusb-1.0.so.0.1.0
7f3fe4a57000-7f3fe4a58000 r--p 00016000 fd:01 527664                     /usr/lib64/libusb-1.0.so.0.1.0
7f3fe4a58000-7f3fe4a59000 rw-p 00017000 fd:01 527664                     /usr/lib64/libusb-1.0.so.0.1.0
7f3fe4a59000-7f3fe4a7a000 r-xp 00000000 fd:01 524860                     /usr/lib64/ld-2.17.so
7f3fe4c4f000-7f3fe4c56000 rw-p 00000000 00:00 0
7f3fe4c56000-7f3fe4c68000 r-xp 00000000 fd:01 535768                     /usr/lib64/libudev.so.1.6.2
7f3fe4c68000-7f3fe4c69000 ---p 00012000 fd:01 535768                     /usr/lib64/libudev.so.1.6.2
7f3fe4c69000-7f3fe4c6a000 r--p 00012000 fd:01 535768                     /usr/lib64/libudev.so.1.6.2
7f3fe4c6a000-7f3fe4c6b000 rw-p 00013000 fd:01 535768                     /usr/lib64/libudev.so.1.6.2
7f3fe4c6b000-7f3fe4c6e000 rw-p 00000000 00:00 0
7f3fe4c78000-7f3fe4c7a000 rw-p 00000000 00:00 0
7f3fe4c7a000-7f3fe4c7b000 r--p 00021000 fd:01 524860                     /usr/lib64/ld-2.17.so
7f3fe4c7b000-7f3fe4c7c000 rw-p 00022000 fd:01 524860                     /usr/lib64/ld-2.17.so
7f3fe4c7c000-7f3fe4c7d000 rw-p 00000000 00:00 0
7ffc98315000-7ffc98336000 rw-p 00000000 00:00 0                          [stack]
7ffc9837b000-7ffc9837d000 r-xp 00000000 00:00 0                          [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]
Aborted (core dumped)

Programmer details:
Code: [Select]
[root@precision ~]# lsusb -v | grep -A29 0x1781
  idVendor           0x1781 Multiple Vendors
  idProduct          0x0c9f USBtiny
  bcdDevice            1.04
  iManufacturer           0
  iProduct                2 FabISP
  iSerial                 0
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           18
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0
    bmAttributes         0x80
      (Bus Powered)
    MaxPower               40mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass      0
      bInterfaceProtocol      0
      iInterface              0
Device Status:     0x0000
  (Bus Powered)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 08, 2018, 11:27:22 am
Help is needed. Tester M644 as in the message "Reply # 5017 on: August 17, 2018, 04:03:16 am". Does not work with firmware 1.33 or 1.34. More precisely, the tester works, but there is no display on the display. I tried different options in the file, nothing happened. Where was I wrong, why does SPI not work?
Code: [Select]
#define LCD_RESET        PB4            /* port pin used for /RES (optional) */
//#define LCD_CS           PB3            /* port pin used for /CS1 (optional) */
#define LCD_A0           PB5            /* port pin used for A0 */
#define LCD_SCL          PB6            /* port pin used for SCL */
#define LCD_SI           PB7            /* port pin used for SI (LCD's data input) */
#define SPI_HARDWARE                    /* hardware SPI */

You're a victim of poor pin assignment. :( Hardware SPI implies PB7 for SCK and PB5 for MOSI. The solution is to switch to bitbang SPI (replace SPI_HARDWARE with following):
Code: [Select]
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SI         /* port pin used for MOSI */
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on October 08, 2018, 11:58:02 am
Hi everyone,
Can somebody post compiled firmware k and m version for AY-AT kit 16MHz.
Like to "play" with them and I am not familiar with programming and so on.
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 08, 2018, 03:45:44 pm
madires Thank you! I did as you wrote, the tester tests the element and immediately turns off. One measurement and immediately shutdown. On firmware 1.13 - this is not a problem. Tester is serviceable. What else can be changed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 08, 2018, 04:18:38 pm
It's the test push button presumably:

Code: [Select]
#define CONTROL_PORT     PORTB     /* port data register */
#define CONTROL_DDR      DDRB      /* port data direction register */
#define CONTROL_PIN      PINB      /* port input pins register */
#define POWER_CTRL       PB1       /* controls power (1: on / 0: off) */
#define TEST_BUTTON      PC7       /* test/start push button (low active) */

PC7 isn't on PORTB. Please check which pin is connected to the test push button and which one enables the power.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on October 08, 2018, 05:38:48 pm
Hello madires.

I have observed a warning when compiling your new version.

I attached some captures so you can see it if it was relevant.

Thank you very much for your attention and greetings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 08, 2018, 05:59:25 pm
madires I checked that the PC7 goes to R5 + R19, PB1 to R17. Scheme - "Reply # 5017 on: August 17, 2018, 04:03:16 am."
Sorry, I took firmware 1.13, file config.h line 431-456
  line 347 - PB1
/ * define the pin button (low value, if pressed) * / 365 - PC7
Everything works well, but I really want to try your firmware.
Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 08, 2018, 06:14:29 pm
I have observed a warning when compiling your new version.

Easy to fix. ;) Please change in tools.c in function Cap_Leakage():
Code: [Select]
  uint16_t          U1;                 /* voltage #1 */
to
Code: [Select]
  uint16_t          U1 = 0;             /* voltage #1 */
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 08, 2018, 06:20:02 pm
madires I checked that the PC7 goes to R5 + R19, PB1 to R17. Scheme - "Reply # 5017 on: August 17, 2018, 04:03:16 am."
Sorry, I took firmware 1.13, file config.h line 431-456
  line 347 - PB1
/ * define the pin button (low value, if pressed) * / 365 - PC7
Everything works well, but I really want to try your firmware.

At the moment the m-firmware requires the test button and the power control to be on the same port. I'll put it on the to-do list.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 08, 2018, 06:30:09 pm
madires
For the Chinese clone, it would be nice without rework ... In the scheme of Nicholas (NickNI) Rev.A0.2 are the same ports of inclusion ....
Thank you! I will wait for the next version of your firmware!
THANKS for your work !!!  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on October 08, 2018, 07:13:10 pm
I have observed a warning when compiling your new version.

Easy to fix. ;) Please change in tools.c in function Cap_Leakage():
Code: [Select]
  uint16_t          U1;                 /* voltage #1 */
to
Code: [Select]
  uint16_t          U1 = 0;             /* voltage #1 */

Hello madires.

Modification made and perfect compilation without warnings.

Thanks and best regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on October 09, 2018, 05:23:39 pm
Hello madires.

I noticed that in the new compilation there are a few small dots left on the screen of my LCR-T4-H.

I attached some photos.

To fix it I had to change the line in the "ST7565R" section:

#define LCD_OFFSET_X                    /* enable x offset of 4 dots */

For this other:

//#define LCD_OFFSET_X                    /* enable x offset of 4 dots */

You may want to point it in your "Clones" file in case someone encounters the same problem.

Thank you very much for the great job you do and greetings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 09, 2018, 08:41:01 pm
Dear madires. Sorry, I dare to ask you again. You can somehow import fonts from Karl-Heinz 1.13 firmware into yours. If necessary, we will all ask Karl-Heinz for permission. It has many fonts and support for many languages. The tester has become international, and the Chinese have made it available anywhere in the world. Thanks you!!! I can not write a new font, I can not master.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 10, 2018, 10:00:41 am
Fonts are organized in a little different way for the m-firmware to reduce the firmware size. Basically you can use the same font bitmaps as in the k-firmware, but you have to rearrange things. The m-firmware uses two tables. One table is a simple lookup table to link the characters 0-255 to bitmaps stored in a font table. This way the font table doesn't have to contain empty character bitmaps, such as ASCII control characters. It's fairly simple.

BTW, if anyone is interested in converting fonts I've written a tool to convert a character bitmap from one orientation/byte order/bit order to another.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 10, 2018, 12:01:48 pm
I guess I didn’t study well ... Can you give me a link where I can see it? Thank!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 10, 2018, 01:05:11 pm
Please have a look at the font_* files in the bitmaps directory of the source code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 10, 2018, 07:40:19 pm
But I do not understand these addresses, it is written for experts. Thanks for taking the time to answer. It remains to either study or wait ...
Regards to you.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: asadof on October 13, 2018, 12:30:19 am
Hello friends
I need pcb  for LCR-T4
Please send me
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 13, 2018, 08:58:58 am
PCB or picture of the PCB? Or schematics?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 13, 2018, 09:15:22 pm
madires
I made a Russian font for 8x8, but some of the letters are not in their proper places. The word is not read correctly. I Do not know how to do it right. Help me please. File with Russian font. The firmware is compiled and works, but the letters are not in the text, they are swapped ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: asadof on October 14, 2018, 01:20:03 am
the PCB pdf  To build
Title: Re: $20 LCR ESR Transistor checker project
Post by: asadof on October 14, 2018, 01:21:32 am
PCB or picture of the PCB? Or schematics?
the PCB
I want to make
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on October 14, 2018, 07:57:02 am
Why should you make the PCB yourself, when it's compleet and so cheap?

https://www.banggood.com/LCR-T4-12864-LCD-Graphical-Transistor-Tester-Resistance-Capacitance-ESR-SCR-Meter-p-1311439.html? (https://www.banggood.com/LCR-T4-12864-LCD-Graphical-Transistor-Tester-Resistance-Capacitance-ESR-SCR-Meter-p-1311439.html?)


There is also a lot of information here:
https://yadi.sk/d/yW8xa5NJgUo5z (https://yadi.sk/d/yW8xa5NJgUo5z)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 14, 2018, 10:53:15 am
I made a Russian font for 8x8, but some of the letters are not in their proper places. The word is not read correctly. I Do not know how to do it right. Help me please. File with Russian font. The firmware is compiled and works, but the letters are not in the text, they are swapped ...

It seems that 0x6f is missing:
Code: [Select]
  0x1C,0x1C,0x1C,0x7F,0x3E,0x1C,0x08,0x00,    /* 0x6e ~ */
 
  0x7F,0x7F,0x49,0x49,0x49,0x79,0x33,0x00,   /* 0x70 'Á' Cyr_B */

Simply insert following between 0x6e and 0x70:
Code: [Select]
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,   /* 0x6f n/a */
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 14, 2018, 12:20:01 pm
Thank!!!  :-+
Works!!!
I added Russian letters for 16 fonts. The firmware is not compiled. Edited letters using the program - KS0108.exe
I find it hard to figure out the addressing.
Thank you so much for the help!

Font 8x8 with Russian for ST7565 - with Russian font, working.

font_8x16_vfp.zip - with Russian characters, requires adjustment - does not work
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 14, 2018, 01:16:24 pm
Great! I'll add both fonts to the next firmware version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mechatrommer on October 14, 2018, 04:24:58 pm
i tried editing firmware ComponentTester-1.34m to work with my TC1 (atMega324PA) Tester, i used TC1-Mod circuit as suggested, so no more STC15W104 chip. the problem is immediate exit (power off) after measurement (or no component), problem similar to...
* once online the device is testing and so on, afterwards it says IMMEDIATELY 'bye' - there is no delay, you cannot even read the values
in page 204...

Have you set the MCU clock to 16MHz in the Makefile?
yes i've edited makefile FREQ = 16, still same problem.

attached is the file i edited (with comment "soa") so i/you can easily track where i edited.
any idea? esp @madires. please help... i've wasted many time on this DANIU TC1 crap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on October 14, 2018, 04:53:57 pm
Hi,

On the website of Mikrocontroller.net where we can find the latest Firmware Karl-Heinz, there are several possible models. Is there a website where you can find a photo with the model ?

Thanks
Modify message
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 14, 2018, 05:51:26 pm
i tried editing firmware ComponentTester-1.34m to work with my TC1 (atMega324PA) Tester, i used TC1-Mod circuit as suggested, so no more STC15W104 chip. the problem is immediate exit (power off) after measurement (or no component), problem similar to...
* once online the device is testing and so on, afterwards it says IMMEDIATELY 'bye' - there is no delay, you cannot even read the values
in page 204...

Sounds like a problem with the test push button at PD1. When not pressed it should be a high signal, and low when pressed. Does the mod create the correct logic levels?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 14, 2018, 05:55:47 pm
On the website of Mikrocontroller.net where we can find the latest Firmware Karl-Heinz, there are several possible models. Is there a website where you can find a photo with the model ?

As Willem52 has already posted: https://yadi.sk/d/yW8xa5NJgUo5z. A few clones are also depicted in Karl-Heinz's excellent  documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mechatrommer on October 15, 2018, 03:12:34 am
i tried editing firmware ComponentTester-1.34m to work with my TC1 (atMega324PA) Tester, i used TC1-Mod circuit as suggested, so no more STC15W104 chip. the problem is immediate exit (power off) after measurement (or no component), problem similar to...
* once online the device is testing and so on, afterwards it says IMMEDIATELY 'bye' - there is no delay, you cannot even read the values
in page 204...

Sounds like a problem with the test push button at PD1. When not pressed it should be a high signal, and low when pressed. Does the mod create the correct logic levels?
you nailed it, thank you! there somekind of leakage making Q2 to always turned ON even if button is not pressed, the solution is i added 100KOhm pull down on the Q2's base. earlier is even worse, Q1 is always ON, it turned out leakage on smd capacitor C13 on the TC1 pcb, so i removed it and now it works. attached is my mod... Q1 and Q2 is 2N3906 and 2N3904 if that matters.

now the tester function as it should, 5 times testing no component, and then turned off. similarly when testing component, transistor for example, it will cycle indefinetely around 3 second each cycle, this is a bit annoying esp when we want to write down components parameters on paper. my M328 tester (now with my brother) is better, it will test component, and it stay there on the output result for longer time. can you direct me on the code how to adjust timeout if component is detected, so its like. if component detected, cycle timeout = say 10 seconds, but if no component, timeout is 3 seconds. or else, how the M328 function?

another thing, there are corrupted image on the right side of my screen, and random garbage on left and top part of the screen, see 2nd attachment. can this be fixed? thanks for your help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 15, 2018, 07:13:39 am
Dear madires. Need your help. I connected the VS1838B IR receiver to the PD4 and the IR transmitter to PB2. But they do not work.
My files, please see where my mistake is.
Thank!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 15, 2018, 10:10:59 am
now the tester function as it should, 5 times testing no component, and then turned off. similarly when testing component, transistor for example, it will cycle indefinetely around 3 second each cycle, this is a bit annoying esp when we want to write down components parameters on paper. my M328 tester (now with my brother) is better, it will test component, and it stay there on the output result for longer time. can you direct me on the code how to adjust timeout if component is detected, so its like. if component detected, cycle timeout = say 10 seconds, but if no component, timeout is 3 seconds. or else, how the M328 function?

When powering on, keep the push button pressed a little bit longer (>300ms) to select the auto-hold mode. You could also enable UI_AUTOHOLD in config.h.

another thing, there are corrupted image on the right side of my screen, and random garbage on left and top part of the screen, see 2nd attachment. can this be fixed? thanks for your help.

Disabling LCD_OFFSET_X and LCD_OFFSET_Y should fix that. The ST7735 drives 132x162 pixels while the LCD has only 128x160. Based on how the LCD is wired to the controller the addressing has to be shifted accordingly by the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 15, 2018, 10:44:57 am
Dear madires. Need your help. I connected the VS1838B IR receiver to the PD4 and the IR transmitter to PB2. But they do not work.
My files, please see where my mistake is.

In your case PD4 is used for the 680 Ohms probe resistor for probe/test pin 2. That means you should connect the IR receiver module to the probes when running the IR detector tool, i.e. SW_IR_RECEIVER. BTW, you've enabled HW_IR_RECEIVER (dedicated pin) and SW_IR_RECEIVER (via probes). PD4 (OC1B) is also used as signal output for the IR transmitter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mechatrommer on October 15, 2018, 08:20:15 pm
Disabling LCD_OFFSET_X and LCD_OFFSET_Y should fix that...
yes it fixes that beyond any reasonable doubt thanks. i've also enabled autohold mode, its much better now. last question.. is there any timeout in autohold mode? so it will shut down automatically? i dont want to forget switch off and this device will drain battery, thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on October 15, 2018, 08:30:58 pm
Hi,

I want to programming my ESR with USBASP and AVRDUDE.
What is the right fuses ?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 16, 2018, 10:20:02 am
i've also enabled autohold mode, its much better now. last question.. is there any timeout in autohold mode? so it will shut down automatically? i dont want to forget switch off and this device will drain battery, thanks.

No, but it might be an idea for the to-do list. What would be a reasonable timeout for the automatic power off when no button is pressed? 30, 60 or 90s?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 16, 2018, 10:31:16 am
I want to programming my ESR with USBASP and AVRDUDE.
What is the right fuses ?

ATmega328, 8 MHz quartz crystal:
avrdude –c usbasp  -p m328p -P usb -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0xfc:m
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 16, 2018, 11:16:05 am
madires Thank! IR receiver works on PC4. I did as you wrote, disconnected //#define SW_IR_RECEIVER and enabled #define HW_IR_RECEIVER
There is a question:
1. Can I connect the IR transmitter to a free port? How to register it?
2. In firmware 1.33, I could change the PWM in Russian. I changed in the variables.h file
     //#endif
  //#if defined (SW_PWM_SIMPLE) || defined (SW_PWM_PLUS)
   // const unsigned char PWM_str[] EEMEM = "PWM";
  #endif
and in the file var_russian.h
#ifdef SW_PWM_SIMPLE
    const unsigned char PWM_str[] EEMEM = "ШИM генератор";
  #endif
Everything worked and displayed in Russian.
 In 1.34m it writes an error when compiling. It can be fixed? How?
Sorry for a lot of questions.
Thanks for the help! Firmware 1.34m for clone M644 - SUPER !!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 16, 2018, 02:15:25 pm
1. Can I connect the IR transmitter to a free port? How to register it?

No, it has to be OC1B (Timer1 is used for generating the carrier).

2. In firmware 1.33, I could change the PWM in Russian. I changed in the variables.h file
     //#endif
  //#if defined (SW_PWM_SIMPLE) || defined (SW_PWM_PLUS)
   // const unsigned char PWM_str[] EEMEM = "PWM";
  #endif
and in the file var_russian.h
#ifdef SW_PWM_SIMPLE
    const unsigned char PWM_str[] EEMEM = "ШИM генератор";
  #endif
Everything worked and displayed in Russian.
 In 1.34m it writes an error when compiling. It can be fixed? How?

Please post the compiler's error message. Also use the complete condition "#if defined (SW_PWM_SIMPLE) || defined (SW_PWM_PLUS)" in var_russian.h. And keep the #endif of the former condition in variables.h. It should be (variables.h):
Code: [Select]
//  #if defined (SW_PWM_SIMPLE) || defined (SW_PWM_PLUS)
//    const unsigned char PWM_str[] EEMEM = "PWM";
//  #endif
and (var_russian.h):
Code: [Select]
  #if defined (SW_PWM_SIMPLE) || defined (SW_PWM_PLUS)
    const unsigned char PWM_str[] EEMEM = "ШИM генератор";
  #endif
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 16, 2018, 03:35:21 pm
Thank you so much! Great, it works !!!  :-+ :-+ :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mechatrommer on October 17, 2018, 08:43:32 am
i've also enabled autohold mode, its much better now. last question.. is there any timeout in autohold mode? so it will shut down automatically? i dont want to forget switch off and this device will drain battery, thanks.
No, but it might be an idea for the to-do list. What would be a reasonable timeout for the automatic power off when no button is pressed? 30, 60 or 90s?
yeah those are about right i was thinking the same thing! ;D let the user decide, as usual a constant configurable in config.h maybe about 1 or 2 minutes or even 5 minutes timeout as default value? we need to run a voting thread i guess :D as for now, i think i'm satified enough i can put the casing back in, until i have another free time to play with the firmware. i just have to remember to switch off my unit manually, otherwise just rechange the battery if its drained, consider it as user's fault. thanks a lot for your help and getting back my unit up.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on October 17, 2018, 05:14:35 pm
Hi,

What is the right firmware for this ESR

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: joeyjoejoe on October 17, 2018, 05:17:08 pm
Hi,

What is the right firmware for this ESR

Thanks


... I already answered in the other thread.

Fish8840TFT
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on October 17, 2018, 08:56:55 pm
Hi,

I checked on Mikrocontroller.net and i don't find Fish8840TFT file.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: netandino on October 17, 2018, 10:32:47 pm
Here are all the files: https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on October 17, 2018, 10:43:20 pm

I've checked in software/trunk but i don't find FISH8840TFT.
I found "mega328_fish8840" and "mega328_fish8840OC" but it does'nt work.
Do you can give me more information or direct link ?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: netandino on October 17, 2018, 10:49:28 pm
I imagine that TFT only refers to the screen, the problem must be the fuse.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on October 17, 2018, 10:57:21 pm

I have uploaded a russian firmware. It work, but in Russian.
The Byte are:

Lfuse: F7
Hfuse: D9
Efuse: FD
LB: 3F

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 18, 2018, 11:59:48 am
In the Karl-Heinz distribution kit there is no support of a clone of Fish8840TFT. In order that its firmware worked it is necessary to make considerable changes in the config.h file.
And here for this clone madires already have ready settings in the Clones file. It is possible to compile easily a new 1.34m from the m-firmware distribution kit. Look at my message https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1532846/#msg1532846 on the  page 190  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on October 18, 2018, 02:02:31 pm
Hi,

If I read well, nothing to do with this model for a newbie like in C. I have an another Fish8840 update to 1.13K. Is it hard to change the time or number of the test before it shut down? It take 6 minutes without component to test before to turn off.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maploid on October 18, 2018, 08:01:12 pm
Hi
i'm hoping someone can help and give me some idea where to start looking.

I've just built a GM328 from Dollatek via Amazon and i'm having trouble getting it to work properly.

The wrong load capacitors were supplied - 220pF instead of 22pF, I only have 15pF to hand so i've used them instead.

If I hold the encoder switch down the display comes on and shows as per the photograph and then shows another screen with the battery voltage.

As soon as I let go of the switch it powers off.  Also, the LED doesn't come on.

Many Thanks

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 18, 2018, 08:13:11 pm
Is the LED's polarity correct? Is T1 switching the LED? 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maploid on October 18, 2018, 09:28:21 pm
Hi Madires

I have tested the LED and Q1 both are working.  What I did find out though was the screen printing is incorrect and the shows the LED the wrong way around.

So the LED now comes on at the same time as the screen and switches off when the switch is released.
Title: Re: $20 LCR ESR Transistor checker project
Post by: asadof on October 19, 2018, 03:06:11 am
I will design my pcb plan. >:D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on October 19, 2018, 08:27:13 pm
Andbro
Found files at 1.32m FishTFT
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 21, 2018, 09:54:34 am
I have tested the LED and Q1 both are working.  What I did find out though was the screen printing is incorrect and the shows the LED the wrong way around.

So the LED now comes on at the same time as the screen and switches off when the switch is released.

And the tester stays on?
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on October 24, 2018, 09:28:31 am
Hi,
I compiled (again...) firmware 1.34m for AY-AT tester, this time with AS7 v7.0.1931.Then I calibrate the AY-AT and save.
I attached all atmel studio folder zipped.
When I test components, R, L and C looks reasonable(22pF,12nF,22nF,22uH,100uH,&K,10K,100K,33K,, but if I test my reference DB237 npn transistor , it shows as UJT.
The tester has 17 cm wires with crocodile endings and I can state I'm very thorough in manipulating the thing.
Calibration and measuring is done with programmer disconnected.I used a linear power supply to power the ay-at (12V, the tester reports 12.04V).

I think something is clearly wrong.
Anyone sees the same behaviour?
If I reprogramm the tester with v1.29 fw (together with .eep file, a saved .eep file after calibration), the transistor detection returns to normal, detected as BJT npn, hFE=58, Vbe= 716 mV.

In order to be perfectly clear, if I leave the transistor connected and I just write .hex+.eep files v1.29m works, v1.34m and v1.33m fail with transistor npn detection.
I appreciate all the work, but I want to point also when something doesn't work (I did 5 years of hardware testing in electronic research& developemment company and have tested
lots of DSP/microcontroller boards with same 'jobs' like voltage/current measuring, adc's , temperature control, laser positioning/ detection, I mean I don't blow the whistle for nothing).
Hoping what seems to me a major issue with the detection rutine will be taken serious, best regards ,
Pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 24, 2018, 11:34:22 am
I don't have a BD237. but I've tested similar types like BD139, BD241B and BD435, and wasn't able to reproduce the issue (two different testers running 1.34m). Have you also checked other BJTs? Has somebody else the same problem?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 24, 2018, 12:57:20 pm
I have checked the BD135,BD129,BD334 transistors for versions 1.34m. I haven't noticed any error - all BJT transistors  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on October 24, 2018, 03:53:31 pm
Hi,
So, I retested a bunch a transistors with 1.34m (most TO220 and smaller case).
Aside ONE transistor, the others look fine.I attached the .txt file with the results.

I may think that one npn is badly marking from fabric!!!, ok, but why the hell 1.29m reports it as bjt and 1.34m as jfet n-ch?

Anyway, I'll stick with 1.34m from now on.
I repeat myself: all resistors, capacitors and inductors report ok.

The BD237 in question seems ok tested with CA5275 and Fluke 110 (diode test, B-E a little more than B-C junction-> 0.637/0.635,
in comparison the BD233 has-> 0.599/0.596).Nothing on C-E junction.

So I'm tired I'll call it forfait this one, one day I'll just put the BD237 into some commutation or amplifier
or something and see on my rigol scope scope if it's working like a bjt one of this days.

Thanks for replying and for your work !!!I'm short of ideas this time...


Best regards,
Pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 24, 2018, 04:40:32 pm
I may think that one npn is badly marking from fabric!!!, ok, but why the hell 1.29m reports it as bjt and 1.34m as jfet n-ch?

That is caused by a change in v1.32m presumably. That change was in the detection of depletion mode FETs to deal with Germanium  BJTs with a high leakage current.

So I'm tired I'll call it forfait this one, one day I'll just put the BD237 into some commutation or amplifier
or something and see on my rigol scope scope if it's working like a bjt one of this days.

Please let me know what you find out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on October 25, 2018, 12:00:42 pm
Hi,
I just did a quick Ic versus Ib characteristic for two BD237, the 'bad one' reported as Jfet n and the good one reported BJT npn (BD237/16).
Simple as hell, I remembered school days :) (base polarised with first power supply with Rb=33k and colector/emiter polarised with second 31V power supply, Rc=18k series resistor on collector).

Then took the currents Ib and Ic via voltage measurements on Rb and Rc.
I varied of course first supply and took values into .xlsx file.Currents are calculated automatic, hFE and Vce also.

The two Q are fine, no question about this.
For me remains a mistery all this, I was sure first Q is badly marked.But no, it's good.The hFE is just smaller but that should be not an issue.
Regards,
Pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: Giox040 on October 31, 2018, 05:59:44 pm
Hi,
I'm a newbie in the AVR world, I'm trying to compile the 1.34m firmware for a DIY Kit "AY-AT" ATmega328 with ST7735 color LCD module on a PC running Windows 10.

I tried to document myself on the forum and at the end I tried to follow the instructions written in the post:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1011926/
but I get these errors:

Code: [Select]
> "make.exe" all
      0 [main] sh 2616 sync_with_child: child 8080(0x15C) died before initialization with status code 0xC0000142
  30735 [main] sh 2616 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
avr-objcopy -O ihex -R .eeprom -R .fuse -R .lock -R .signature ComponentTester ComponentTester.hex
avr-objcopy -j .eeprom --set-section-flags=.eeprom="alloc,load" --change-section-lma .eeprom=0 --no-change-warnings -O ihex ComponentTester ComponentTester.eep || exit 0
      0 [main] sh 4448 sync_with_child: child 6160(0x158) died before initialization with status code 0xC0000142
   1383 [main] sh 4448 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
make.exe: [makefile:137: ComponentTester.eep] Error 128 (ignored)
avr-objdump -h -S ComponentTester > ComponentTester.lss
      0 [main] sh 8036 sync_with_child: child 6472(0x158) died before initialization with status code 0xC0000142
  22093 [main] sh 8036 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
make.exe: *** [makefile:141: ComponentTester.lss] Error 128

> Process Exit Code: 2
> Time Taken: 00:01

in the makefile at line 141 I find:    avr-objdump -h -S $< > $@


Are the instructions I followed still valid? can someone help me?

Thank You in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 01, 2018, 06:35:21 pm
That looks like a problem with the tool chain.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 01, 2018, 08:42:35 pm
Hi,
I'm a newbie in the AVR world, I'm trying to compile the 1.34m firmware for a DIY Kit "AY-AT" ATmega328 with ST7735 color LCD module on a PC running Windows 10.

I tried to document myself on the forum and at the end I tried to follow the instructions written in the post:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1011926/
but I get these errors:

Code: [Select]
> "make.exe" all
      0 [main] sh 2616 sync_with_child: child 8080(0x15C) died before initialization with status code 0xC0000142
  30735 [main] sh 2616 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
avr-objcopy -O ihex -R .eeprom -R .fuse -R .lock -R .signature ComponentTester ComponentTester.hex
avr-objcopy -j .eeprom --set-section-flags=.eeprom="alloc,load" --change-section-lma .eeprom=0 --no-change-warnings -O ihex ComponentTester ComponentTester.eep || exit 0
      0 [main] sh 4448 sync_with_child: child 6160(0x158) died before initialization with status code 0xC0000142
   1383 [main] sh 4448 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
make.exe: [makefile:137: ComponentTester.eep] Error 128 (ignored)
avr-objdump -h -S ComponentTester > ComponentTester.lss
      0 [main] sh 8036 sync_with_child: child 6472(0x158) died before initialization with status code 0xC0000142
  22093 [main] sh 8036 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
make.exe: *** [makefile:141: ComponentTester.lss] Error 128

> Process Exit Code: 2
> Time Taken: 00:01

in the makefile at line 141 I find:    avr-objdump -h -S $< > $@


Are the instructions I followed still valid? can someone help me?

Thank You in advance.
I just compiled in Atmel Studio 7 selecting the makefile from project repo for my ay-at tester then programmed the chip with as7 and an utk500 clone. winavr it's past... so go for it if you like newer and simplier solutions. the gui is not bad at all
regards, pierre

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 01, 2018, 08:50:43 pm


Hi,
I'm a newbie in the AVR world, I'm trying to...

and with as7 you don't have to struggle if you compile newer stuff like atmega328pb with winavr you have to bang your head to the wall to set it up and write correctly the fuses etcetera. as7 knows all the atmel chips, have newer gcc correctly configured and just works out of the box.
don't forget to point the project to the makefile, hit build and write fw and eep.

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on November 02, 2018, 07:13:33 am
Hello Giox040.

Maybe this will help you:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1729157/#msg1729157 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1729157/#msg1729157)

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Giox040 on November 02, 2018, 04:02:18 pm
madires, perieanuo and pepe10000, I thank you very much for your help.

I reinstalled WinAVR-20100110 and copied over WinAVR-20100110.rar suggested by perieanuo and I managed to compile without errors.

I have not burn the chip yet because first I have to check the parameters in the config files but there should not be any problems because the size of the .hex and .eep files looks correct.

Now I would also like to try Atmel Studio 7 and later I will do the installation.

Thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: plouc68000 on November 03, 2018, 07:38:48 am
Hello, I have ported the latest firmware 1.13k to the Arduino Online Tools ( no Tools  install needed for Verify and upload  :-DD)

It works with Arduino/Genuino UNO and Arduino Mega 2560 Hardware

Read the ReadMe-adoc file for Details

The  ArduTester V1.13 Project is here:

https://create.arduino.cc/editor/plouc68000/71ba4559-fff1-49f3-8a50-1c1ad9682262/preview
 (https://create.arduino.cc/editor/plouc68000/71ba4559-fff1-49f3-8a50-1c1ad9682262/preview)

May be some Arduino enthousiast may have a look, test it and Report

(https://reho.st/self/76250894120a99aebbd19d42c818d183e3176efc.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on November 03, 2018, 04:17:22 pm
plouc68000, welcome to the forum. That's pretty neat. I had heard of this online IDE, but never tried it before. Thanks for the heads up on your port of the project.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 03, 2018, 04:47:21 pm
Nice! pighixxx has done an Arduino port and a transistor tester shield a few years ago, but I have no idea what happened to his project.
Title: Re: $20 LCR ESR Transistor checker project
Post by: plouc68000 on November 04, 2018, 10:41:20 am
Well, I was looking in the pighixxx Arduino UNO port  ::) and thinking its time to give a new life to it.....Arduino has made some progress since that time...( in behaving Real Time   :clap: )

So I kept the same pins definition for the LCD and the Test Button as pighixxx, but for the software, I took
another approach, I ported all the latest original TransistorTester files to the Arduino online IDE....

I removed Assembly code where it was not really necessary and  because the IDE don't like it   :scared:, example the wait routines....

The performance loss compared to the official .HEX file for UNO is surprizing small, and its so easy to modify, verify, upload  :-DD

I tested components from a Super UNO R3 Starter Kit, such a Starter Kit contains everything you need to build the Tester...without solder iron

https://www.ebay.com/itm/Smraza-for-Arduino-UNO-Starter-Kit-with-Tutorials-compatible-with-Arduino-UNO/113053229644?hash=item1a527f624c:g:v~0AAOSwkLJbHdAN:rk:2:pf:0 (https://www.ebay.com/itm/Smraza-for-Arduino-UNO-Starter-Kit-with-Tutorials-compatible-with-Arduino-UNO/113053229644?hash=item1a527f624c:g:v~0AAOSwkLJbHdAN:rk:2:pf:0)

-The UNO R3 Controller
-The LCD1602 Module
-The Breadboard
-The resistors, Push Buttos, jumper wires, USB cable

so 2N2222 tested OK, 2N7000 tested OK, Diodes, LED, dual LED,resistors 10 Ohm, 1K, 22K, 1MOhm tested OK, C from 33pF, 330pF, 22nF, 100nF, 2,2 microF, 220 microF Tested OK, L 5mH tested OK


---- Limitations due to ressources taken by Arduino resident code ( T0 interrupt )

In the UNO, the Frequency counter won't verify because conflicting with Timer use of Arduino, so this function is not available.

You can overcome this limitation by using a Arduino MEGA 2560 Board, which has more timers.....



Title: Re: $20 LCR ESR Transistor checker project
Post by: asadof on November 04, 2018, 07:29:35 pm
Hello friends
Which tester is better
Title: Re: $20 LCR ESR Transistor checker project
Post by: asadof on November 04, 2018, 07:30:45 pm
Which one will I make?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 04, 2018, 07:42:21 pm
It's your decision. ;) Any specific requirements?
Title: Re: $20 LCR ESR Transistor checker project
Post by: farokh on November 07, 2018, 12:52:05 am
It's your decision. ;) Any specific requirements?
hello, im looking for the schematic and software for the newest version of this amazing project but there is 212 pages and almost its impossible to read all the post. please could you help me on that? i need a guid to build the newest version for 2x16 lcd and newset for graphical lcd. please send it to my email or give me a link. thank you. my email: softwarekardo@gmail.com.
could you help me please?
Title: Re: $20 LCR ESR Transistor checker project
Post by: CatalinaWOW on November 07, 2018, 12:54:29 am
I suggest you go to reply number 6 on page 1 and follow the link.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 07, 2018, 01:59:06 am
It's your decision. ;) Any specific requirements?
hello, im looking for the schematic and software for the newest version of this amazing project but there is 212 pages and almost its impossible to read all the post. please could you help me on that? i need a guid to build the newest version for 2x16 lcd and newset for graphical lcd. please send it to my email or give me a link. thank you. my email: softwarekardo@gmail.com.
could you help me please?

I suggest you wait more than 14 minutes for a reply before repeating yourself.
Title: Re: $20 LCR ESR Transistor checker project
Post by: farokh on November 07, 2018, 02:02:02 am
It's your decision. ;) Any specific requirements?
hello, im looking for the schematic and software for the newest version of this amazing project but there is 212 pages and almost its impossible to read all the post. please could you help me on that? i need a guid to build the newest version for 2x16 lcd and newset for graphical lcd. please send it to my email or give me a link. thank you. my email: softwarekardo@gmail.com.
could you help me please?

I suggest you wait more than 14 minutes for a reply before repeating yourself.
thanks for your suggestion, i removed the replay!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on November 07, 2018, 09:56:46 am
Please look also at all the information here:
https://yadi.sk/d/yW8xa5NJgUo5z
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on November 07, 2018, 06:39:15 pm
Please look also at all the information here:
https://yadi.sk/d/yW8xa5NJgUo5z
Yes, the info there is correct, but the software there is in Russian.
Not usefull for most of us.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 08, 2018, 07:01:24 am
Not usefull for most of us.
And what hinders to look at makefile and to change language from Russian to that language which to you native?
And then to compile a new firmware for the clone. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: plouc68000 on November 08, 2018, 07:36:24 am
all the software (compiled binaries in english) you find on Github here, select the right hardware/display combination :

https://github.com/svn2github/transistortester/tree/master/Software/trunk (https://github.com/svn2github/transistortester/tree/master/Software/trunk)

or on SVN :

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)


A 2 lines 16X2 display dont tell me enough to help you  , you should specify if its a parallel interface or I2C or SPI ?

if you want to start easy and learn with a 2 Line 2X16 with parallel, you may use the Arduino_m2560 files with a Arduino Mega....

https://github.com/svn2github/transistortester/tree/master/Software/trunk/arduino_m2560 (https://github.com/svn2github/transistortester/tree/master/Software/trunk/arduino_m2560)


You can find all hardware to make your TransistorTester in a Arduino starter kit like this, the 1602 display included is the 2 X 16 parallel:

https://www.ebay.com/itm/Ultimate-Starter-Kit-For-Arduino-MEGA-2560-LCD1602-Motor-LED-Relay-DIY-Set/192619118814?hash=item2cd8fe80de:rk:1:pf:0 (https://www.ebay.com/itm/Ultimate-Starter-Kit-For-Arduino-MEGA-2560-LCD1602-Motor-LED-Relay-DIY-Set/192619118814?hash=item2cd8fe80de:rk:1:pf:0)

You can then upload the binary code with the Arduino IDE.

ALL this can be done WITHOUT RECOMPILATION OF THE CODE  :-DD, I have started to learn this way ......






Title: Re: $20 LCR ESR Transistor checker project
Post by: vinceroger on November 10, 2018, 01:16:09 pm
Im just about to build UP a ay-at tester kit im going to use a 20mhz crystal and change the voltage regulator, just a question can these measure small value smd capacitors? if so what the lowest capacitor value reading these go down to thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on November 10, 2018, 02:17:14 pm
sORRY FOR my stubid question

But can it check POWER BJTs correctly & MOSFETs?
2N3005 IRF9240 etc
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 10, 2018, 03:29:53 pm
Im just about to build UP a ay-at tester kit im going to use a 20mhz crystal and change the voltage regulator, just a question can these measure small value smd capacitors? if so what the lowest capacitor value reading these go down to thanks

The sampling ADC method of the k-firmware running at 16MHz can measure caps with a resolution up to about 0.01pF. The standard capacitance measurement starts at 25pF for the k-firmware and 5pF for the m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 10, 2018, 03:48:03 pm
But can it check POWER BJTs correctly & MOSFETs?
2N3005 IRF9240 etc

Yes. BTW, 2N3005 is a SCR.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on November 10, 2018, 05:20:05 pm
But can it check POWER BJTs correctly & MOSFETs?
2N3005 IRF9240 etc

Yes. BTW, 2N3005 is a SCR.

Sorry
 I mean 2N3050
Is hfe readings correct for it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 10, 2018, 07:25:58 pm
Yes and no. The TransistorTester uses a low test current and the hFE value will be correct for that test current. But datasheets of power BJTs state the hFE for a specific high test current usually, and it will be different for a low test current.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Benik3 on November 10, 2018, 10:51:00 pm
Hi there.

Maybe stupid question, but which HW you can recommend to buy? (around 10$, I looked on GM328A).
With support of Markus FW...

Thank you :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 11, 2018, 12:16:55 am
Any tester with an ATMega 328 will support Markus' firmware. Avoid the TC1 variant. I also suggest you read at least page 1 and the last 10 pages of this forum topic. Good luck.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on November 11, 2018, 09:51:43 am
Yes and no. The TransistorTester uses a low test current and the hFE value will be correct for that test current. But datasheets of power BJTs state the hFE for a specific high test current usually, and it will be different for a low test current.

tHANX!

cAN yOU SAY HOW TO MEASURE POWER TRANSISTORS cORRECTLY?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 11, 2018, 12:45:57 pm
To check if the hFE of a power BJT matches the datasheet you would have to set up a simple test circuit with the currents and voltages given in the datasheet. Or if you like to know the hFE for your specific application than use those currents. For example, the 2N3055's datasheet states a hFE of 20 - 70 at an I_C of 4A and a hFE of 5 or more at an I_C of 10A. Scrolling down the datasheet you might see a diagram with I_C/hFE curves at different temperatures. hFE isn't a single "correct" value.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alextuning15 on November 11, 2018, 10:27:09 pm
Hello, greetings to all, it is a pleasure to be here in this forum, I have a tester m328 lcr-t4, only three days of use, suddenly I stop working, it does not turn on the screen. I did tests to verify what the problem would be, check the 78L05 regulator, repair a track of the circuit that was GND and had to be 5+, I made measurements to the pins of the mega 328, where it has to have 5v, it has 9v, the pins 3, 4, 5, 6, 18, 22, 23, 26 are GND.
I am a beginner in electronics, I bought the device to make things easier, but it only lasted three days, I think it is imitation of the original purchased on Aliexpress.

Excuse my English, use the Google translator. https://www.aliexpress.com/item/2016-V2-68-ESR-T4-Mega328-Digital-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP/32680013678.html?spm=a2g0s.9042311.0.0.378463c0DEZJd2 (https://www.aliexpress.com/item/2016-V2-68-ESR-T4-Mega328-Digital-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP/32680013678.html?spm=a2g0s.9042311.0.0.378463c0DEZJd2)


Excuse my English, use the Google translator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: cdev on November 12, 2018, 02:31:37 am
alextuning15, welcome!

just from looking at the picture and the fact that you didn't bring it up, I'm guessing the chip isn't socketed, right? If it is (socketed) replacing it (if its indeed blown) and replacing or repairing the voltage regulator would be fairly easy. Sounds like you are getting a good start in troubleshooting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alextuning15 on November 12, 2018, 12:06:53 pm
Thank you for your prompt response, voltage regulator 78L05, I did the test and if you are regulating at 5 volt, something else, test that pin 18 of mega 328 is connected to GND and not 5 volt, I imagine that the track or connection is fused and that's why it's not working, I'll have to make the connection by means of an electric cable
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 12, 2018, 07:55:32 pm
There have been a few reports of shorts between PCB layers. Maybe try holding it up to a strong light.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alextuning15 on November 13, 2018, 12:44:25 am
I gave up, I made tests and all the 5 volt connections are connected with GND, you are difficult of what I thought to repair the equipment, I prefer to buy another, but, I do not know if the same, to have the damaged spare or other of better quality, what do you recommend?

I have checked with backlight, to verify the PCB and I do not observe anything strange.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 14, 2018, 12:54:34 pm
Hi

Is it too complex to explain?
How change the language and compile the file from Clone Ttester?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2018, 04:42:28 pm
k-firmware: in Makefile (UI_LANGUAGE =LANG_ENGLISH etc. )
m-firmware: in config.h (UI_ENGLISH, UI_GERMAN, etc.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 14, 2018, 05:16:01 pm
Hi,

What is the difference between the K-Firmware and M-Firmware ?

If i understand, i donwload K-Firmware V1.13 and i replace the original makefile with the makefile in CloneTtester ?
I compile and it's over ?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: pishta on November 14, 2018, 05:21:00 pm
can someone make a newbs guide to flashing the firmware of these? I have the USB bootloader device. Dont know what pins go where. currently have 1.12k but its an original 2016 build
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2018, 07:21:24 pm
What is the difference between the K-Firmware and M-Firmware ?

The differences are explained in the README file of the m-firmware.

If i understand, i donwload K-Firmware V1.13 and i replace the original makefile with the makefile in CloneTtester ?

What do you mean by "CloneTtester"?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2018, 07:30:35 pm
can someone make a newbs guide to flashing the firmware of these? I have the USB bootloader device. Dont know what pins go where. currently have 1.12k but its an original 2016 build

There are tons of guides about programming an AVR via ISP, e.g. http://www.ladyada.net/learn/avr/programming.html. (http://www.ladyada.net/learn/avr/programming.html.) The TransistorTester isn't any different. The important point is to program flash (.hex) and EEPROM (.eep).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 14, 2018, 08:27:55 pm
Hi,

Clone Ttester is a Russian who has made differents firmwares for many ESR. He has many model not included in MicroKontroller.net.
The problem, it's in Russian.

See the link: https://yadi.sk/d/yW8xa5NJgUo5z

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2018, 08:42:46 pm
I see. Karl-Heinz offers compiled firmwares for several clones. You just need to identify your tester model and check the trunk directory for a match.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 14, 2018, 09:25:42 pm
Hi,

It's the only on Clone Ttester have found the updated the firmware for the model FISH8840 with TFT.
I've try this firmware, it's very good but only in Russian.
I don't know if it's possible to change the language in English and how to change and what software to use.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 15, 2018, 08:27:13 am
Hi,

Clone Ttester is a Russian who has made differents firmwares for many ESR. He has many model not included in MicroKontroller.net.
The problem, it's in Russian.

See the link: https://yadi.sk/d/yW8xa5NJgUo5z

Thanks

Hi! It is my archive.
As not only Russian-speaking people use this archive, I decided to add new firmwares from k-firmware in English for different clones.
In the next several days I will add archive thus, as shown in a screenshot. You monitor changes in archive.
If dear madires to me allows to use its work, I can add to archive new compiled firmwares UI_ENGLISH for m-firmware? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on November 15, 2018, 03:14:26 pm
Thanks, but it's kind of really big at over half a giga-byte..!!  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 15, 2018, 03:19:48 pm
If dear madires to me allows to use its work, I can add to archive new compiled firmwares UI_ENGLISH for m-firmware? :)

I'm fine with that. Happy compiling! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 15, 2018, 03:28:11 pm
Thanks, but it's kind of really big at over half a giga-byte..!!  :)
I am not guilty that Chinese made so many different clones! :-DD  Send all claims to them (it is a joke). :D
If it is serious, then it is not obligatory to download all archive, it is possible to download separately only that folder for a clone which is necessary to you.
This resource allows to make it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on November 16, 2018, 01:40:39 am
ATmega644/1284 DIP and SMD.
I told ya I was slow. I'll post more if they work. Odds are probably around 50/50 that this will work. It will take me at least a few days to get them further along and tested which probably means weeks...if I'm lucky. This is intended as a development board with as much design flexibility as I could come up with. It is designed with an absolute minimum circuit preconfigured. Everything else is broken out on perfboard adapters. Both the SMD and DIP breakout configurations are unified. They are single sided with jumpers and just shy of 150mm ×150mm. Almost the entire microcontroller is broken out onto perfboard footprints.
  This board is probably the worst transistor tester version ever designed. I haven't configured the power supply, startup circuit, display or anything. They are just connected to blank perfboards. ...but...there are 5 possible power supply rails routed to most of the breakout boards. Almost the entite uC is on ta 5×7cm. The leftover PA port is on a 2×8cm that should be cut to 7cm. The PB, PC, and PD ports are each on their own independent 3×7cm breakout with all power supply rails setup on the opposite side from the port header. Each port board has extra pins on each header routed centrally to easily connect between ports using a jumper. I'm mounting these in a bench enclosure similar to what Marcus posted. I intend on using ribbon connectors for a display and interface, but I also added a rotary encoder and test socket footprint on the main board. These are routed for proper connections. However, I have also added header footprints to make them independent and the trace connections are setup to use 0r 0805 resistors for configuration. I have added 0r resistors in several locations for a fully customized configuration.
  I still have a lot of work to do before releasing the KiCAD files and schematic as my designators and schematics are a mess right now. The final and extensively modified artwork for the etch was done using GIMP. After several failed attempts at learning DIY photoresist, I tried to make something that is as easy as possible to work with. All pads are much larger than is typical and I did my best to maximize trace width and spacing. I might have made them a little smoother too. The SMD version only uses cardinal direction jumpers. Unfortunately a few compromises were made on the DIP board and it has some wires. It also has a tricky socket configuration but I've got rivets to remedy the mechanical strength issue.
  ...anyways...I'm probably just pointlessly rambling at this point... Let me know if anyone is interested in more info
-Jake
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on November 16, 2018, 03:13:18 am
Not sure I completely follow everything. Will await your drawings to get a better handle on it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: meebro on November 17, 2018, 05:10:19 am
Hello, I have added 0.1 resistors with suggested voltage reference/regulator to the AY-AT kit (8MHZ), with no problems on original 1.12k firmware included. But when i tried using different m and k firmwares with different ICs, i always get a blank screen that is no use to me.

Both precompiled and self compiled versions have been tried to no avail.  :--
I have been burning the hex and eeprom files via the 328p in an Arduino UNO hooked up to a USBasp connected to PC.
avrdude has no errors with fuses (E:FC, H:D9, L:F7).

Is there anything I have been doing wrong the whole time? Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 17, 2018, 11:13:02 am
Different LCD controller? The AY-AT's display has a ST7735 usually. Does the backlight stay on for a few seconds after powering on?
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on November 17, 2018, 07:54:19 pm
Hello everyone.

Acquired temperature sensor DS18B20 for use in the original Chinese firm (GM328 Kit) and with the firm of Madires.

https://www.ebay.es/itm/DS18B20-Temperature-Temp-Sensor-Waterproof-Digital-Thermal-Probe-1M-BSG/122969181538?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 (https://www.ebay.es/itm/DS18B20-Temperature-Temp-Sensor-Waterproof-Digital-Thermal-Probe-1M-BSG/122969181538?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649)

With the firm of Madires works perfectly.

But with the Chinese firm, it asks to put the probe, I connect it as it indicates and this other screen appears and from there it does not happen.

(http://i65.tinypic.com/2jdqc1s.jpg)

Has any user had the same problem and has it been solved?

Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on November 17, 2018, 08:09:14 pm
Schematic attached. I've already noticed a couple more errors after creating the PDF but this is still representative of the basic schematic. I was going to try to redo the designators but I'm too lazy at this point.
  Over all the whole idea is to make a board that uses perfboard as little "shield" adapters. By soldering a socket strip on my board, and pin headers on the outside edges of standard sized perfboard I have an adaptable design that I can revise and update various parts of the circuit however I want. This is just a way to test other people's designs or make my own.
 I picked up an bunch of TQFP 644's for $0.90 each, so I made the SMD version first. The DIP version is more polished so I've shown it here.

  I have some Dupont Dynamask, but I haven't tried it yet. I have a few other smaller projects I've been playing with. If the Dynamask works well with the smaller projects then I have the masks already made for this project to do them too. This is why they are liquid tin coated. I'm still trying to work out how I want to do designators on the board. I've thought about, 1) trying silk screening, 2) incorporating them in the solder mask, or even 3) experimenting with photoresist film and paint (although I imagine I need to use an epoxy). Anyways, that's why I don't have a proper designator layer printout yet.

Suggestions/direction/ideas are always welcome with me. I'm no expert.
-Jake
Title: Re: $20 LCR ESR Transistor checker project
Post by: meebro on November 17, 2018, 09:11:23 pm
Different LCD controller? The AY-AT's display has a ST7735 usually. Does the backlight stay on for a few seconds after powering on?

The main IC on the LCD is an HEF4050BT. Model of the screen is 1982AY-CX. Backlight stays on until power off on 1.34m firmware. I have gotten a precompiled version of "ComponentTester-trendy-1.25m for AY-AT" to work, however. Do you have a compiled version of the new firmware that might work with my tester?

EDIT: the "mega328_color_kit" k firmware seems to work. But now i would like to try to get yours to work.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2018, 12:48:21 pm
The 4050 CMOS is used as a level shifter to drive the 3.3V LCD controller. My guess is that you've selected a different LCD driver or signal wiring. Please try the settings for the AY-AT listed in the Clones file!
Title: Re: $20 LCR ESR Transistor checker project
Post by: meebro on November 18, 2018, 06:29:45 pm
Thank you, everything is working fine now!
Title: Re: $20 LCR ESR Transistor checker project
Post by: j395 on November 22, 2018, 04:43:59 pm
v1.13k (m328p) for some reason detects 51-Ohm resistors as 1 or 2 diodes.

other values measures ok, except <1 Ohm not detected, calibration done.
what can be done about it ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 22, 2018, 05:09:55 pm
v1.13k (m328p) for some reason detects 51-Ohm resistors as 1 or 2 diodes:

other values measures ok, except <1 Ohm not detected, calibration done.
what can be done about it ?
they never managed to do correct detections, I noticed myself multiple bugs with almost all versions, the tester is just a kid's toy.
But screwing up resistors, it's a really achievement :)
imho they are trying so hard to do lots of stuff they forget stable detection and measurement contraints.should measure slower and better this thing, maybe a microcontroller/memory facelift is needed.
In 2016 in a company I worked they did 5 digits multimeter with an TI device, never missed a voltage or resistor measurement, in the same price category.but the programmer was a real deal.I was the hw guy :)
best regards,pierre
edit:I always power from battery or linear lab supply, needed to be clear I saw later your problem was the power supply :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 22, 2018, 05:22:34 pm
5 digits DMM for 12 bucks?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 22, 2018, 05:28:14 pm
v1.13k (m328p) for some reason detects 51-Ohm resistors as 1 or 2 diodes:

other values measures ok, except <1 Ohm not detected, calibration done.
what can be done about it ?

Have you checked also other 51 Ohms resistors? Or a 47 or a 56 Ohms resistor?
Title: Re: $20 LCR ESR Transistor checker project
Post by: j395 on November 22, 2018, 06:05:07 pm
Quote
Have you checked also other 51 Ohms resistors? Or a 47 or a 56 Ohms resistor?
hm, looks like switching supply issue (powered from lithium power bank controller MP3401A (http://tefatronix.g6.cz/images/pb1rev.png)).
With linear supply measures ok
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 22, 2018, 06:15:48 pm
Yep, it's a known issue that powering the tester with a SMPSU can cause strange results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 22, 2018, 06:22:07 pm
5 digits DMM for 12 bucks?
something like 22-24 euros.the price I payed for ay-at when it was new on the market.(project did in France, manufactured in Hungary, 20 boards fabricated and tested.)
after volume prod, it becamed cheaper.
do you want me to explain further cost vs volume?
by the way, how much do you pay for pcb, lcd, uC?we payed below 2.xx for uC/dsp (my boss used cheap controllers/dsp), board is some euros tested, resistor and capacitors are pennys, lcd was cheap, dac also.you think it cost how much, 200???
I sense a little tension here and I really don't get what bothers you.
the answeer is YES it was surely below 25 euros for sure.
I wasn't doing accounting, just boards, projects, testing, a little scripting, some C++, and a little price survey for some products.So I saw the prices for almost all products leaving the company, thoe I was responsible for only 2 big ones.
in your oppinion, how much it costs a v-a-r meter within this precision?I just had on my hands 0.1 mA ampermeter AND 1mV voltmeter produced 4 euros for 1 piece with STM/12 bit DAC/LED display.
4 bucks!!!
I realise my oppinion concerning this at328 tester's software dislike some readers, but a sw bug is a sw bug, need to be treated and it's not my first time I told a programmer hi is doing a shitty job and needs to revise it all.myself I rewrite stuff for my uC projects all the time and I'm not angry for correcting MY mistakes.
So if you have another experiences with project prices, doesn't mean all of us walk the same path.
pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 22, 2018, 06:39:31 pm
We don't manufacture any TransistorTesters. There are simply too many regulations and additional costs associated with manufacturing and selling electronics in Germany. For example, we would have to prepay the e-waste disposal, a system which discriminates small manufacturers with low volumes. Anyway, it's an OSHW project. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: j395 on November 22, 2018, 06:49:01 pm
C8051F350 with 24-bit ADC, 1-128x PGA, precision reference and 2 DACs costs 2$ (https://ru.aliexpress.com/item/C8051f350-gqr-c8051f350-gq-c8051f350-qfp-32-5/32850130874.html) (like cheapest arduino nano/pro), but contains only 8K flash.
ideal solution for precision U/I/RLC-meter
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 22, 2018, 08:18:12 pm
it's not my first time I told a programmer hi is doing a shitty job
So this probably won't be the first time you've been called an asshat
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 23, 2018, 07:00:43 am
it's not my first time I told a programmer hi is doing a shitty job
So this probably won't be the first time you've been called an asshat
I know, truth hearts :)
Btw, can you do a better sw for this gadget?my answer is here if you get it.
I didn't remember talking to you ...maybe returning to your code is a good idea
i.m done testing a neverending project, I'm used to ones that ends in months :)
Thanks to those who worked on this (god knows I tried a little bit)
Pierre


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Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on November 23, 2018, 03:53:31 pm
C8051F350" ... "(like cheapest arduino nano/pro), but contains only 8K flash.
ideal solution for precision U/I/RLC-meter
If I recall the date correctly, the AVR TT project goes all the way back to 2009 in it's original form with the ATmega8. A similar design might be possible using something like the Silicon Labs chip. I haven't found many sources to walk me through using those 8051s though. I haven't looked into the specs of the 350 but I have a few C8051F310s (because they have a hardware USB port). I could be wrong but it looks like I need a Silicon Labs programmer and have to use simplicity studio or Keil. So my choices are either not very well documented for beginners/Elmer Fuds like me, or extremely overpriced software.
   The Silicon Labs 8051s I've looked at all seem to have an odd 3v port design with some that are 5v tolerant but they don't have 5v analogue. When it comes to programming toolchains that are accessible to the majority of people around the world it is almost impossible to find a more accessible and cheap option than the USBasp or Arduino as ICSP. There are tutorials available on the internet in almost any language with these devices.

  Contrary to what many people like myself try to do with this project, according to the project developers, "this is a design intended to explore the potential of a simple 8 bit AVR using the minimum amount of hardware while exploring the potential of the software." The actual OSHW project is extremely well documented. All of the clones fail to follow the project as specified in the documentation. I have created schematics detailing two of these and their failures. The fact that both firmwares have tried to accommodate these devices is remarkable and everyone should be thankful for this.

  If anyone wants a fully functional, "bug free" device, go build the project spec yourself as hundreds of others have done. If anyone complains about what they are given for free as a gift, be aware it clearly marks your character, and everyone is left wondering why you are here. If anyone sees a problem they know how to fix, it's simple, be a class act, fix the problem and submit the change to the developers. Complaining about a free gift is insane.
-Jake
Title: Re: $20 LCR ESR Transistor checker project
Post by: deriterkeeg on November 23, 2018, 04:14:26 pm

they never managed to do correct detections, I noticed myself multiple bugs with almost all versions, the tester is just a kid's toy....
bla bla bla
...I was the hw guy :)

[/quote]
We're convinced that you certainly are an excellent circuit designer. It'd be interresting to see a better version of this tester. May you propose a design ?
TIA
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 23, 2018, 04:39:42 pm
C8051F350" ... "(like cheapest arduino nano/pro), but contains only 8K flash.
ideal solution for precision U/I/RLC-meter
If I recall the date correctly, the AVR TT project goes all the way back to 2009 in it's original form with the ATmega8. A similar design might be possible using something like the Silicon Labs chip. I haven't found many sources to walk me through using those 8051s though. I haven't looked into the specs of the 350 but I have a few C8051F310s (because they have a hardware USB port). I could be wrong but it looks like I need a Silicon Labs programmer and have to use simplicity studio or Keil. So my choices are either not very well documented for beginners/Elmer Fuds like me, or extremely overpriced software.
   The Silicon Labs 8051s I've looked at all seem to have an odd 3v port design with some that are 5v tolerant but they don't have 5v analogue. When it comes to programming toolchains that are accessible to the majority of people around the world it is almost impossible to find a more accessible and cheap option than the USBasp or Arduino as ICSP. There are tutorials available on the internet in almost any language with these devices.

  Contrary to what many people like myself try to do with this project, according to the project developers, "this is a design intended to explore the potential of a simple 8 bit AVR using the minimum amount of hardware while exploring the potential of the software." The actual OSHW project is extremely well documented. All of the clones fail to follow the project as specified in the documentation. I have created schematics detailing two of these and their failures. The fact that both firmwares have tried to accommodate these devices is remarkable and everyone should be thankful for this.

  If anyone wants a fully functional, "bug free" device, go build the project spec yourself as hundreds of others have done. If anyone complains about what they are given for free as a gift, be aware it clearly marks your character, and everyone is left wondering why you are here. If anyone sees a problem they know how to fix, it's simple, be a class act, fix the problem and submit the change to the developers. Complaining about a free gift is insane.
-Jake
About the 'character' remark,I need to precise something:I reported bug to make sw better not for criticism.
ALL the sw makers I crossed in my career did the same thing, crying out load when you point a mistake/non-conformity, I had to do it because of ISO standards and became a habit.
The clones are almost same hw as original project, and if you change fw and something stops workin' you don't blame hw.
I'm not complaining I point what's not ok and when someone tells me 'it.s like this...' I feel my hours spent for testing and retesting are just stupid.
If you don't want feedback, just say so,don't blame the tester.and when the tester tells you for several fw something it's not ok matbe you start thinking less options and more stable detection.that's my philosophy and I'll not give it up just cause someone it's blessed in his professional image.
Me when I do an error I just shut it up and repair it.


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Title: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 23, 2018, 04:41:49 pm

they never managed to do correct detections, I noticed myself multiple bugs with almost all versions, the tester is just a kid's toy....
bla bla bla
...I was the hw guy :)

We're convinced that you certainly are an excellent circuit designer. It'd be interresting to see a better version of this tester. May you propose a design ?
TIA
[/quote]
My capacities are not in discussion here, the tester firmware is.
First free idea for the tester:
Add an 1.5 dollar 16 bit adc and move on.
Good enough for your royal highness?


Envoyé de mon iPad en utilisant Tapatalk
Title: Re: $20 LCR ESR Transistor checker project
Post by: cdev on November 23, 2018, 07:10:44 pm
My $15 TTester actually does surprisingly well at testing inductors, something which is probably the most difficult thing it does. It cant test very low value inductors with any resolution but what it does display is right to 10% or so. Which is good enough for many things.

Not good enough for RF work, but good enough for typical RF chokes, power supplies, etc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 23, 2018, 07:29:41 pm
...I was the hw guy :)

Yes we can see that you're a stereotypical HW guy... no social skills.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 23, 2018, 09:23:54 pm
My capacities are not in discussion here, the tester firmware is.
First free idea for the tester:
Add an 1.5 dollar 16 bit adc and move on.

You're not the first one suggesting an external ADC. It's a little bit more complex than you might think. The hardware and the software form a symbiotic relationship to get the maximum out of a very simple hardware. For example, the three MCU pins for the probes are used as ADC inputs and also in output mode (pull up/down) for some checks. And typically the next suggestion is to take a MCU with more IO pins (enter you preferred inexpensive MCU here). Oh, it's a 3.3V one. But we need 5V to drive several semiconductors. So we would have to add an external switching matrix. Our intention is to keep the design simple and we don't want to create an overengineered FrankenTester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 24, 2018, 02:07:04 pm
Hi,

I have not received again my Gm328A SMD.
Do you can tell me if resistors 680R and 470K are package 0603 or 0805? I want replace the resistors with 0.1%

Thanks

Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 24, 2018, 08:14:27 pm
My capacities are not in discussion here, the tester firmware is.
First free idea for the tester:
Add an 1.5 dollar 16 bit adc and move on.

You're not the first one suggesting an external ADC. It's a little bit more complex than you might think. The hardware and the software form a symbiotic relationship to get the maximum out of a very simple hardware. For example, the three MCU pins for the probes are used as ADC inputs and also in output mode (pull up/down) for some checks. And typically the next suggestion is to take a MCU with more IO pins (enter you preferred inexpensive MCU here). Oh, it's a 3.3V one. But we need 5V to drive several semiconductors. So we would have to add an external switching matrix. Our intention is to keep the design simple and we don't want to create an overengineered FrankenTester.
I just put one on a i2c project for getting mA resolution.and lowered speed.on 5v only atmega328.I tend to add stuff do do things,but for 10bit adc it was an obligation, the other solution was to remaster the pcb.
Regards,pierre


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Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on November 24, 2018, 08:23:24 pm
@madires
I see most people consider here the project is carved in stone.As I mentioned,I did a derivate with some extra, suits me well for staying beside fluke, chauvin arnoux and co :)
But honestly I can't stand some other 'contributions ' level so this discussion for me is over, I posted this last time here cause I wanted to pay you my respects, I get you're a serious person.
I'll modify the sw like a grown up now I get some spare time.
Have a nice we !


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Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 26, 2018, 08:20:14 pm
Hi,

What is the right firmware for this ? 16 Mhz

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 26, 2018, 08:44:40 pm
That's an AY-AT. IIRC, it has an 8MHz crystal by default. So you should use the settings for the AY-AT, change the MCU clock setting to 16MHz and compile the firmware. For the k-firmware simply take mega328_color_kit as starting point and for the m-firmware use the AY-AT settings from the Clones files.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 26, 2018, 11:44:18 pm
Hi,

Probably I must put 16.
# The OP_MHZ option tells the software the Operating Frequency of your ATmega.
OP_MHZ = 8

N:B I'm a newbie
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 26, 2018, 11:57:53 pm
Hi,

Is it really better to replace the 7550 by MCP1702T-5002E-5.0.LDO and the TL431 by LT4040AIZ-2.5 and finally the crystal by 16 MHz Cload 20pf?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 27, 2018, 06:09:25 am
> Is it really better to replace the 7550 by MCP1702T-5002E-5.0.LDO
Yes. More accurate voltage input = more accurate measurement.

> the TL431 by LT4040AIZ-2.5
No. TL431 can be completely removed after installing the precision LDO

> the crystal by 16 MHz
Yes this improves the measurement process.

All of this is explained in the readme.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 27, 2018, 06:40:32 am
Hi,

Clone Ttester is a Russian who has made differents firmwares for many ESR. He has many model not included in MicroKontroller.net.
The problem, it's in Russian.

See the link: https://yadi.sk/d/yW8xa5NJgUo5z

Thanks
Hi! It is my archive.
As not only Russian-speaking people use this archive, I decided to add new firmwares from k-firmware in English for different clones.
In the next several days I will add archive thus, as shown in a screenshot. You monitor changes in archive.

Hi!
I added for all known clones fresh firmwares of k-firmware revision 804 in English!
In the English folder 2 more folders for quartz resonators on 16 and 8 MHz are located. I will remind that use of quartz allows not only to increase the speed and accuracy of measurements by 16 MHz and also allows to use function of testing of quartz and ceramic resonators in the range from 0.4-13 MHz.  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 28, 2018, 11:48:16 am
Hi,

If I understand, I replace the 5volts regulator for MCP1702T-5002E-5.0.LDO and I can remove in hardware the 2.5volts référence IC?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: j395 on November 28, 2018, 01:21:42 pm
I could be wrong but it looks like I need a Silicon Labs programmer and have to use simplicity studio or Keil

I'm currently testing C8051F350 in Linux with SDCC, Arduino-pro as primitive programmer (only read/write/erase flash, no debug), and python console app for uploading firmware...
comparing to AVR, characteristics of oscillator, reference and ADC looking impressive, at least in datasheet...
cost of programmer and IDE approaching zero :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 28, 2018, 09:02:34 pm
If I understand, I replace the 5volts regulator for MCP1702T-5002E-5.0.LDO and I can remove in hardware the 2.5volts référence IC?

TL431 can be completely removed after installing the precision LDO

All of this is explained in the readme.

From the README:
Quote
"If you don’t install the precision voltage reference and you don’t add the relay extension, you should install a pull up resistor R16 to PC4 with a higher resistance value (47k?). This helps the software to detect the missing voltage reference."

You really should read the readme.  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 29, 2018, 11:15:43 am
☹️ Sorry I don't find this read me. It's not easy to find where is the right information.
I feel like in a labyrinth. 🙄 If anyone can send this Readme file, with a great attention I will read this.
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 29, 2018, 11:29:00 am
Does the Readme file is:
TransistorTester with AVR microcontroller
and a little more
Version 1.13k
Karl-Heinz K¨ubbeler
kh kuebbeler@web.de
October 31, 2017

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2018, 11:35:24 am
You'll find the latest version at https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on November 29, 2018, 11:40:53 am
Thanks 👍
Title: Re: $20 LCR ESR Transistor checker project
Post by: MikeLud on December 01, 2018, 11:15:58 pm
I just finished building an AY-AT with all of the below upgrades. Which firmware should I use K or M? It came with 1.12k.

If you get an AY-AT Clone, the following is a list of hardware corrections to order if you would like to optimize it's operation on M-Firmware. If you normally order parts from Mouser or Digikey all information and links are provided. (No Supplier Affiliation/No Financial Affiliate Program Links) This is simply a resource to make the information easier for the next person to find.
AY-AT Clone - The Proper Mods
1.) 0.1% Probing Resistors
2.) 20mhz Crystal
3.) Correct LDO Vreg
4.) Correct Vref

Manufacturers Part Number=MPN
Mouser Part Number=MoPN
Digikey Part Number=DkPN

(3×)470k Resistors
TE Connectivity
MPN: H8470KBZA
Metal Film Resistors - Through Hole H8 470K 0.1% 100PPM
MoPN: 279-H8470KBZA ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=H8470KBZAvirtualkey50680000virtualkey279-H8470KBZA[/url])
$0.97each (8/2017)
$2.91 (×3)
DkPN: PTF475KCCT-ND ([url]https://www.digikey.com/product-detail/en/te-connectivity-passive-product/H8470KBZA/H8470KBZA-ND/2373532[/url]) (not stocked)
Dk Alt:
475k 0.1% 1/8W
Vishay Dale
MPN: PTF56475K00BYEB
DkPN: PTF475KCCT-ND ([url]https://www.digikey.com/product-detail/en/vishay-dale/PTF56475K00BYEB/PTF475KCCT-ND/2273757[/url])
$1.64each (8/2017)

(3×)680ohm Resistors
TE Connectivity
MPN: H8680RBYA
Metal Film Resistors - Through Hole H8 680R 0.1% 15PPM
MoPN: 279-H8680RBYA ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=H8680RBYAvirtualkey50680000virtualkey279-H8680RBYA[/url])
$1.14each (8/2017)
$3.42 (×3)
DkPN: H8680RBYA-ND ([url]https://www.digikey.com/product-detail/en/te-connectivity-passive-product/H8680RBYA/H8680RBYA-ND/2373526[/url])(not stocked)
Dk Alt:
681ohm 0.1% 1/4W
Note: listed as discontinued by digikey (w/available stock 8/2017)
TT Electronics/Welwyn
MPN: RC55Y-681RBI
DkPN: 985-1036-1-ND ([url]https://www.digikey.com/product-detail/en/tt-electronics-welwyn/RC55Y-681RBI/985-1036-1-ND/2401900[/url])
$1.70each (8/2017)

20mhz Crystal
CTS
MPN: ATS20A
Crystals 20MHz 20pF 30ppm -20C 70C
MoPN: 774-ATS20A ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=ATS20Avirtualkey67110000virtualkey774-ATS20A[/url])
$0.36 (8/2017)
DkPN: CTX1106-ND ([url]https://www.digikey.com/product-detail/en/cts-frequency-controls/ATS20A/CTX1106-ND/2640038[/url])
$0.36 (8/2017)

Spare ATmega328
Microchip
MPN: ATMEGA328-PU
8-bit Microcontrollers - MCU AVR 32K FLSH 1K EE2K SRAM-20MHz IND
MoPN: 556-ATMEGA328-PU ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=ATMEGA328-PUvirtualkey55660000virtualkey556-ATMEGA328-PU[/url])
$1.95each (8/2017)
DkPN: ATMEGA328-PU-ND ([url]https://www.digikey.com/products/en?keywords=ATMEGA328-PU[/url])
$1.96each (8/2017)

2.5 Volt 0.1% Precision Reference
Texas Instruments
MPN: LM4040AIZ-2.5/NOPB
Voltage References Prec MicroPwr Shunt Vtg Ref
MoPN: 926-LM4040AIZ25NOPB ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=LM4040AIZ-2.5%2fNOPBvirtualkey59500000virtualkey926-LM4040AIZ25NOPB[/url])
$1.72 (8/2017)
DkPN: LM4040AIZ-2.5/NOPB-ND ([url]https://www.digikey.com/products/en?keywords=LM4040AIZ-2.5%2FNOPB[/url])
$1.73 (8/2017)

5v LDO Voltage Regulator
Microchip
MPN: MCP1702-5002E/TO
LDO Voltage Regulators LDO w/ Low Quiescent
MoPN: 579-MCP1702-5002E/TO ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=MCP1702-5002E%2fTOvirtualkey57940000virtualkey579-MCP1702-5002E%2fTO[/url])
$0.52each (8/2017)
DkPN: MCP1702-5002E/TO-ND ([url]https://www.digikey.com/products/en?keywords=MCP1702-5002E%2FTO[/url])
$0.49each (8/2017)

Total
Mouser: $10.88 (8/2017)
(+USA Econ Shipping@$4.99)
Digikey: $14.56 (8/2017)
(+ Shipping I'm too lazy to look this up)

Mouser USA Part Links Consolidated:
470k Resistors ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=H8470KBZAvirtualkey50680000virtualkey279-H8470KBZA[/url])
680ohm Resistors ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=H8680RBYAvirtualkey50680000virtualkey279-H8680RBYA[/url])
20mhz Crystal ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=ATS20Avirtualkey67110000virtualkey774-ATS20A[/url])
ATmega328 ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=ATMEGA328-PUvirtualkey55660000virtualkey556-ATMEGA328-PU[/url])
LM4040 Vref ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=LM4040AIZ-2.5%2fNOPBvirtualkey59500000virtualkey926-LM4040AIZ25NOPB[/url])
MCP1702 LDO Vreg ([url]http://www.mouser.com/Search/ProductDetail.aspx?R=MCP1702-5002E%2fTOvirtualkey57940000virtualkey579-MCP1702-5002E%2fTO[/url])
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 02, 2018, 01:34:25 am
Whichever one you like better. Grab a spare mcu on eBay to make it easier to swap back and forth.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 02, 2018, 02:05:51 am
Hi,

What is the difference to use a 20Mhz 20pf and a 16 MHz 20pf?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 02, 2018, 01:51:48 pm
Sorry, but I don't understand your question. Could you please rephrase it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 02, 2018, 02:32:12 pm
Hi,

With the model AY-AT, does I must replace the crystal by 16 MHz or 20 MHz?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 02, 2018, 04:15:52 pm
Both firmwares (k & m) support 16 and 20 MHz. It's up to you. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on December 03, 2018, 07:03:49 am
In other words, you don't have to change the crystal. The tester will work fine the way it is. But, if you want to change it, you can.
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on December 04, 2018, 05:03:13 pm
Hello everyone again,

Following this (https://www.instructables.com/id/Component-Tester-Test-Almost-Anything-/) tutorial, I made the board with some modifications.

(http://i64.tinypic.com/15hd9gi.png)

(http://i64.tinypic.com/2v15jyx.jpg)

http://i68.tinypic.com/rbytmg.jpg (http://i68.tinypic.com/rbytmg.jpg)


Modified PDF here - http://drive.google.com/file/d/1eWQ1JPqDr-VY0eYVAq7BssBGCY0T0Xl-/view?usp=sharing (http://drive.google.com/file/d/1eWQ1JPqDr-VY0eYVAq7BssBGCY0T0Xl-/view?usp=sharing)

I'm facing some problems:

1) Intermittent power issue. Device refuses to switch on sometimes. Have to press ON button repeatedly to get it to switch on. Soldered a 100nf ceramic cap each on input/output of 7805 and issue has reduced but it still occurs. Sometimes device switches off while probing a component. No short on caps or resistor.

2) I'm looking to replace bulky 7805 with mt3608-5v5v. Firmware thinks battery is low and tries to switch off. What code should I change in which file? R11 and R12 are probing PS input on pin 28(PC5). Do I need to change values of these resistors?

3) Looking for a cheap lcd with 4-5 segment display and simple I2C connections or equivalent. How to proceed? Code change? Compatible displays supported by firmware?

4) Any firmware on github that supports the encoder? I tried a few but the encoder stops working.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 04, 2018, 06:20:27 pm
1) Intermittent power issue. Device refuses to switch on sometimes. Have to press ON button repeatedly to get it to switch on. Soldered a 100nf ceramic cap each on input/output of 7805 and issue has reduced but it still occurs. Sometimes device switches off while probing a component. No short on caps or resistor.

Typical issues with the power section are a PNP (Q7 in your case) with a low hFE or too small caps before and after the voltage regulator.

2) I'm looking to replace bulky 7805 with mt3608-5v5v. Firmware thinks battery is low and tries to switch off. What code should I change in which file? R11 and R12 are probing PS input on pin 28(PC5). Do I need to change values of these resistors?

Please use the latest firmware and adjust the power management settings config.h. 1.20m is quite old.

3) Looking for a cheap lcd with 4-5 segment display and simple I2C connections or equivalent. How to proceed? Code change? Compatible displays supported by firmware?

The current firmware supports several graphic LCDs (mostly SPI, a few I2C, monochrome and color). See
https://github.com/svn2github/transistortester/tree/master/Software/Markus for the m-firmware.

4) Any firmware on github that supports the encoder? I tried a few but the encoder stops working.

The rotary encoder needs to be enabled in config.h and the pins are set in config_328.h.

Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on December 04, 2018, 06:56:44 pm
@madires

Thank you for the short and quick answer  ^-^

The aluminium caps I used were 10uf/25v which I referred from fig 2.1 in ttester.pdf file. I will try changing the bc328-40 with a bc557b

There are three types of of firmware in the /Markus folder - a) ComponentTester* 2) *classic* and 3) *trendy*; What do they mean?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 04, 2018, 07:33:13 pm
I've meant the firmware with the highest version number, i.e. ComponentTester-1.34m.tgz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on December 05, 2018, 07:08:13 am
Defining 16x02 lcd in config_328.h file gave me this error  :(

(http://i68.tinypic.com/2laueqd.png)
Title: Re: $20 LCR ESR Transistor checker project
Post by: j395 on December 05, 2018, 07:56:36 am
seems like some files are in different encodings (CP866 etc) - need to convert all to UTF8
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on December 05, 2018, 09:35:38 am
Thank you

Converting bitmaps/font_HD44780_cyr.h and bitmaps/font_HD44780_int.h to UTF8 has solved it.

Device has booted. But calibration mode is not working. Device shows component tester 1.34m on screen and it switches off  :-\

Edit: Solved it. There is a lever in config that can enable/disable calibration via probe short method

btw, can anyone tell me what causes efuse to fail in the make fuses command

Code: [Select]
D:\component tester\ComponentTester-1.34m>make fuses
avrdude -c USBasp -B 10.0 -p m328p -P usb -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U
 efuse:w:0xfc:m

avrdude: set SCK frequency to 93750 Hz
avrdude: warning: cannot set sck period. please check for usbasp firmware update
.
avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x1e950f
avrdude: reading input file "0xf7"
avrdude: writing lfuse (1 bytes):

Writing | ################################################## | 100% 0.02s

avrdude: 1 bytes of lfuse written
avrdude: verifying lfuse memory against 0xf7:
avrdude: load data lfuse data from input file 0xf7:
avrdude: input file 0xf7 contains 1 bytes
avrdude: reading on-chip lfuse data:

Reading | ################################################## | 100% 0.02s

avrdude: verifying ...
avrdude: 1 bytes of lfuse verified
avrdude: reading input file "0xd9"
avrdude: writing hfuse (1 bytes):

Writing | ################################################## | 100% 0.02s

avrdude: 1 bytes of hfuse written
avrdude: verifying hfuse memory against 0xd9:
avrdude: load data hfuse data from input file 0xd9:
avrdude: input file 0xd9 contains 1 bytes
avrdude: reading on-chip hfuse data:

Reading | ################################################## | 100% 0.02s

avrdude: verifying ...
avrdude: 1 bytes of hfuse verified
avrdude: reading input file "0xfc"
avrdude: writing efuse (1 bytes):

Writing |                                                    | 0% 0.00s ***faile
d;
Writing | ################################################## | 100% 0.08s

avrdude: 1 bytes of efuse written
avrdude: verifying efuse memory against 0xfc:
avrdude: load data efuse data from input file 0xfc:
avrdude: input file 0xfc contains 1 bytes
avrdude: reading on-chip efuse data:

Reading | ################################################## | 100% 0.02s

avrdude: verifying ...
avrdude: verification error, first mismatch at byte 0x0000
         0xfc != 0x04
avrdude: verification error; content mismatch

avrdude: safemode: efuse changed! Was fc, and is now 4
Would you like this fuse to be changed back? [y/n] n
avrdude: safemode: Fuses OK

avrdude done.  Thank you.

make: *** [fuses] Error 1

Also, sometimes, when device is switched on with no component connected to probes, the display shows random values(T1-T2 130uF 60 ohm) and it keeps cycling with random values forever. What's going on?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 05, 2018, 12:48:56 pm
Hi,

If I change the voltage regulator 5v and the voltage reference 2.5v, does I must modify a value(s)  in in firmware? (exemple AY-T)

Thanks

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 05, 2018, 12:58:31 pm
btw, can anyone tell me what causes efuse to fail in the make fuses command

Code: [Select]
avrdude: verification error, first mismatch at byte 0x0000
         0xfc != 0x04

Simply ignore that error. It's caused by an error in avrdude's standard configuration file.

Also, sometimes, when device is switched on with no component connected to probes, the display shows random values(T1-T2 130uF 60 ohm) and it keeps cycling with random values forever. What's going on?

Are you powering the tester with a SMPSU?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 05, 2018, 01:04:40 pm
If I change the voltage regulator 5v and the voltage reference 2.5v, does I must modify a value(s)  in in firmware? (exemple AY-T)

In most cases no changes are required. But you could check the voltage of the new reference and adjust the value in the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 05, 2018, 01:20:02 pm

Where I must change the new Vref value in firmware?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 05, 2018, 04:02:39 pm
k-firmware: change value 2495 in Calibrate_UR.c
m-firmware: change UREF_25 in config.h
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on December 06, 2018, 07:46:48 am
Are you powering the tester with a SMPSU?
Yes, a bench power supply
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 06, 2018, 11:00:46 am
Please try a linear power supply. SMPSUs can cause strange results (known issue).
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on December 06, 2018, 01:30:30 pm
Yes, powering it with 9v bat has solved it but my intermittent power issue has returned. I had replaced bc327-40 with bc557b because stores here dont keep bc557c and ordering from aliexp will take a month  :'( will try stores in another city

Btw, there are two st7735 displays(besides the bare (https://www.aliexpress.com/item/1-8-1-77-inch-Color-TFT-LCD-Display-Module-128x160-Display-ST7735-SPI-Serial-interface/32887596525.html?spm=2114.search0604.3.8.68fc2208OKIX4i&ws_ab_test=searchweb0_0,searchweb201602_5_10065_10068_319_10059_10884_317_10887_10696_100031_321_322_10084_453_10083_454_10103_10618_10307_538_537_536,searchweb201603_51,ppcSwitch_0&algo_expid=d66a008e-f623-40d0-8c8f-5de35085cc80-1&algo_pvid=d66a008e-f623-40d0-8c8f-5de35085cc80) version) on aliexp. This (https://www.aliexpress.com/item/1-8-Inch-TFT-ST7735S-LCD-Display-Module-128x160-For-Arduino-51-AVR-STM32-ARM/32921513325.html?spm=a2g0s.13010208.99999999.282.726b3c004uhKfv) and this (https://www.aliexpress.com/item/1-8-1-8-Inch-TFT-LCD-Display-Module-Micro-SD-Card-Slot-ST7735S-Controller-128x160/32954234937.html?spm=a2g0s.13010208.99999999.275.726b3c004uhKfv)

There is a  chip on one I don't recognize. Do you know?

(http://i68.tinypic.com/dbjckm.png)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 06, 2018, 02:09:09 pm
There is a  chip on one I don't recognize. Do you know?
74HC245 - 8-bit transceiver with 3-state outputs
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 06, 2018, 04:10:02 pm
U1 isn't a zener, it's a 3.3V LDO. And U2 is used as level shifter to drive the 3.3V display with 5V signals. The other LCD module has no level shifter, just a 3.3V LDO.
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on December 06, 2018, 06:26:48 pm
U1 isn't a zener, it's a 3.3V LDO
Yes

662k is a an LDO
Z14(BZX84C3V3 (http://www.mouser.com/ds/2/149/BZX84C3V3-888845.pdf)) is a zener
Both come in sot-23 package and can be interchanged

fish8840tft has an st7735 display. Earlier versions used Z14. Later versions use 662k
Title: Re: $20 LCR ESR Transistor checker project
Post by: j395 on December 10, 2018, 12:47:06 pm
what about audio continuity tester? generate tone on PC3 when resistance < some value? or even variable tone depending on resistance or voltage
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 11, 2018, 07:33:55 am
Hi, madires!
There is a question on m-firmware 1.34 for the SSD1306 0,96" display I2C (128x64). The picture icons is shifted to the left side, can propose a solution of this problem? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: j395 on December 11, 2018, 11:59:42 am
Quote
icons is shifted to the left side
SH1106 (132x64) ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: towe96 on December 11, 2018, 01:24:07 pm
Today I've started messing around with the component tester I've had for a few years now - an AY-AT chinese clone that came with 1.12k.

After trying 1.34m (does that really have so few features? Or was I missing some sort of key sequence to enter the menu?), I went and flashed the precompiled 1.13k for the "mega328-color-kit" from the "trunk" folder - works fine.
I tried doing a "make all" on the files myself because of some detail option I'd have liked to change, but I couldn't get it to compile smaller than around 35k, much too large for the 32k Flash on the ATmega328P. How'd that happen? The precompiled file fit perfectly at iirc 97% memory usage.

How can I get it to compile smaller than that? I'm using WinAVR portable (20100110)'s command line.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 11, 2018, 09:18:22 pm
Yes there is a menu with more features. Look in the Markus readme for details.

The firmware should fit unless you enable too many options. Make sure you are using intel binary. Try a different compiler .I am using avr-gcc 8.2 (2018)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 12, 2018, 12:16:43 am
Hi,

I know how to compilateur the Karl-Heinz firmware. But I don't know how to compile the Marcus firmware.
Does anyone can help me?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 12, 2018, 01:20:14 am
which part are you having trouble with?

Did you read under the section "Building the firmware" in the Markus readme?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 12, 2018, 01:32:23 am

With Karl-Heinz you put the makefile for your model in c:\trunk\default folder and you use WinAvr-Make All. With Markus, I don't know where I must put the files.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 12, 2018, 01:55:27 am
Sorry I'm not familiar with Winavr.

I simply adjust the makefile (per the readme), and then run "make". I don't need to put the the files anywhere.
Title: Re: $20 LCR ESR Transistor checker project
Post by: towe96 on December 12, 2018, 07:56:28 am
No need to put files anywhere.
Just unzip the version you'd like to use.
Have a look at the "Clones" file - in there you'll find settings for most mass produced boards.
Copy these settings in the "config.h" file and make sure nothing is active in the "config_328.h" file.

Also you may want to set the correct "PROGRAMMER" and "PORT" in the "Makefile".

Then, just run "make all" in that direction, and flash it using avrdude.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 12, 2018, 02:30:25 pm
Hi,

If anyone has a AY-AT clone and has compiled with Marcus. 1.34, if you can share you Makefile, hex, eep I will be happy.
I don't know how to configure the Marcus firmware. With an exemple, that's will possible to study the difference in config.h and the Makefile.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 12, 2018, 03:51:25 pm
Andbro, see https://yadi.sk/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke (https://yadi.sk/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 12, 2018, 07:27:36 pm
Hi Indman,

The firmware of Marcus for M328+TFT is in Russian. I have copied all files from the folder 1.34mRus(16MHz) to the folder ComponentTester-1.34m.
I have modified in config.h UI_Russian for UI_ENGLISH. After i opened makefile and use WINAVR_Make All, but i have error.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 12, 2018, 08:12:27 pm
Andbro, i used for creation of an firmware of an icon of elements with the resolution of 32х32 therefore add to the ST7735.c file in the section *fonts and symbols* the line #include "symbols_32x32_hf.h". This section has to look so:
/* fonts and symbols */
/* horizontally aligned, horizontal bit order flipped */
#include "font_8x8_hf.h"
#include "font_8x16_cyrillic_hf.h"
#include "font_10x16_hf.h"
#include "symbols_24x24_hf.h"
#include "symbols_30x32_hf.h"
#include "symbols_32x32_hf.h"
 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 12, 2018, 08:57:41 pm
Thansk Indman,

Now it start. Is it normal it's impossible to calibrate and the rotary encoder functions are not available ?

Thanks again
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 13, 2018, 06:32:04 am
If the tester is operational, then calibration should be carried out as it is written to instructions. Everything works for me normally. For check of operability of external enkoder it is necessary to include an option in config.h 
#define SW_ENCODER
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 14, 2018, 06:04:38 pm
There is a question on m-firmware 1.34 for the SSD1306 0,96" display I2C (128x64). The picture icons is shifted to the left side, can propose a solution of this problem? :)

That looks like a different controller. The SSD1306 is monochromatic. BTW, a bad virus hit me and I'm feeling awful.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 14, 2018, 06:30:21 pm
Madires, now I understand why you did not come several days on a forum.
I wish you good health quicker to win against this virus!
Title: Re: $20 LCR ESR Transistor checker project
Post by: badjob on December 16, 2018, 05:08:49 pm
I bought a TC-1 and went through the trouble of flashing it. Looks like the russian FW's screen size is incorrect. You get sparkle pixels on the edges and on my unit it looks like the plastic was mis-glued, covering part of the screen. Through the config and moving the sticker I was able to get it like this. Also the config makes it probe over and over instead of stopping, making the release useless.

Anyone using one of these and has it filling the screen and not cut off?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 17, 2018, 10:07:19 am
badjob,try this firmware.
https://yadi.sk/d/ponaYiG41uygPQ
Whether there will be a picture shift?
Setup of provision of the picture at Markus it is made in the config_644.h file for ST7735:
//#define LCD_OFFSET_X     4               /* enable x offset of 2 or 4 dots */
//#define LCD_OFFSET_Y     2               /* enable y offset of 1 or 2 dots */
You can change these settings for correct information on the display and compile the new firmware.
Also the config makes it probe over and over instead of stopping, making the release useless.
Read attentively a manual on use of a firmware, especially that part where process of management of a tester by means of short and longer clicking of the Test button speaks. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheGeologist on December 23, 2018, 12:07:35 am
Hello all.

I've recently purchased one of these kits from AliExpress (red board, SCM ATMEGA328P DIP-28, 160x128 pixel 16 bit color display, etc.) and am in the process of ensuring it is good to go before constructing the board.  However, in the docs from www.mikrocontroller.net/ (http://www.mikrocontroller.net/) it recommends the following:

The resistors R1 to R6 are critical for measurements and this 680 and 470k resistors should be measurement type resistors (tolerance of 0.1%) to get the full accuracy.


The kits resistors are all bog standard 1% type. I've been to the local Altronics store and search Jaycar online and can't find these low tolerance components.  I've searched the forum here for advice on sourcing these components, but had no luck (me or the search function?  Who can say!).

Can anyone point me in the right direction to find suitable components?  Given I only need a small number and from what I can see from online suppliers (Element14, Mouser, etc.) the parts will be worth close to the value of the rest of the unit!  :o

Many thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 23, 2018, 12:56:27 pm
The probe/test resistors don't need to have 0.1% tolerance. If you can't buy any for a reasonable price try to match 1% types.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 23, 2018, 09:55:26 pm
I think you can sort of compensate by measuring your resistors with the highest precision instrument you have, and then enter those values into the config. Of course this won't correct for temperature and drift.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on December 23, 2018, 10:26:28 pm
drift wont be an issue if used indoors, it's not like your using it in snow one day and baking heat the next.
there is equipment that could apply to, such as multimeters - but not a component tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 23, 2018, 11:36:31 pm
You could be right. I actually don't know if you took it outside where there is a 20 deg difference, how much the measurements actually change.

But lower tolerance resistors also change more over time don't they? I suppose this would be mitigated by running the calibration every year.
Title: Re: $20 LCR ESR Transistor checker project
Post by: j395 on December 24, 2018, 04:28:20 pm
Quote
advice on sourcing these components, but had no luck
use 1K/1M multi-turn trimmers (like Bourns 3266/3296/3299), calibrate  with accurate ohmmeter
Title: Re: $20 LCR ESR Transistor checker project
Post by: CheckOne Two on December 30, 2018, 10:46:07 am
Hi all .. been using the m1.32 FW for a while now but just had the srv05-4 diode array give up on me (nothing to do with caps) ... I've been trying to find the spec of it to get a better quality replacement but it's obviously a really cheapo part and none of the aliexpress etc. ads have any spec on them. I'd rather replace with a better quality part than any more of these V05's.

I notice that a few of you are using a relay and it's also documented in the manual ... seems like a good idea to me ... can any of you who've been using a relay without problems for a while now recommend me a part number or suitable spec?

I took the opportunity to update to the 1.34 firmware but I have noticed that it doesn't ask for a capacitor anymore while self testing/calibrating ... (I've checked back over the files for compilation a couple of times now and also compared them to my last settings and can't see anything obviously out of place ... has anybody else noticed this or is it calibrating the same as it did before for the rest of you?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 30, 2018, 11:19:57 am
I don't recommend buying a relay. The relay circuit will cost you more than a new 328P.
Salvaged parts are ideal, and almost any two pole relay can be made to work.
Obviously, a 5V coil will be easier to hook up. I would use something small so your battery lasts longer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 30, 2018, 11:30:08 am
Hi all .. been using the m1.32 FW for a while now but just had the srv05-4 diode array give up on me (nothing to do with caps) ... I've been trying to find the spec of it to get a better quality replacement but it's obviously a really cheapo part and none of the aliexpress etc. ads have any spec on them. I'd rather replace with a better quality part than any more of these V05's.

www.onsemi.com/pub/Collateral/SRV05-4-D.PDF (http://www.onsemi.com/pub/Collateral/SRV05-4-D.PDF), Littelfuse, Bourns ...

I notice that a few of you are using a relay and it's also documented in the manual ... seems like a good idea to me ... can any of you who've been using a relay without problems for a while now recommend me a part number or suitable spec?

I'm using Fujitsu FTR-B3 series (FTR-B3CA4.5Z) for testing. Anyhow, I prefer to simply discharge any cap before connecting it to the tester.

I took the opportunity to update to the 1.34 firmware but I have noticed that it doesn't ask for a capacitor anymore while self testing/calibrating ... (I've checked back over the files for compilation a couple of times now and also compared them to my last settings and can't see anything obviously out of place ... has anybody else noticed this or is it calibrating the same as it did before for the rest of you?

The m-firmware doesn't ask for a self-adjustment capacitor, but the k-firmware does. When running the m-firmware perform three checks of a film cap (100nF - 2.2µF) in a row before running the self-adjustment. It's explained in the README file. The hardware option for a fixed self-adjustment cap is also supported.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CheckOne Two on December 31, 2018, 04:29:10 am
Thanks for the info both of you .. I'll see if I can find a scrap relay.

I'm usually pretty vigilant at discharging and normally use my LCR meter for caps but still have the odd brain fog moment once in a while and broken test equipment can be a real inconvenience |O so I always think any extra protection for test gear is a good idea for me.

That's good to know that the 1.34 FW doesn't ask for a ref cap ... I must be remembering way back to when I got the kit at first and it had 1.12  k-FW on it ... should be working fine then ...  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MAntunes on January 04, 2019, 03:44:17 pm
Hi guys!

When I was soldering my AY-AT kit I dropped the SRV05-4 chip and I can't find it.
Is this component really needed? Can the tester work without it until I get a replacement?

Also, where can I get the latest firmware (.hex file) for using with a 20MHz crystal? What is the difference between the K and M firmwares?

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 04, 2019, 05:07:03 pm
The tester works also fine without the SRV05-4 (input protection). The m-firmware's README file explains the differences between both firmwares. IIRC, there is no ready-to-program version for 20MHz. So I'd recommend to compile it yourself.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MAntunes on January 04, 2019, 05:17:45 pm
The tester works also fine without the SRV05-4 (input protection). The m-firmware's README file explains the differences between both firmwares. IIRC, there is no ready-to-program version for 20MHz. So I'd recommend to compile it yourself.

Is the README you are talking about the one inside this folders? More particularly the 1.34m?
https://github.com/svn2github/transistortester/tree/master/Software/Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 04, 2019, 06:20:33 pm
Yes, each firmware tgz archive includes the README.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Southerner on January 04, 2019, 07:32:10 pm
Is there a repository for the current and past firmware versions?  Where is it?
Can newer or newest versions be flashed to older hardware versions?

I have 2 or 3 different GM328's.  I keep trying to find a case for one and even the vendors saying they have it end up sending me the current (new) version case which does not fit older versions.

Also my present stock of the GM328's seem to have one shortfall that I hate.  That is that they do not read capacitor values down to say 4pf.  In fact, one of them will not even read down to 22pf!

Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 04, 2019, 08:31:34 pm
Is there a repository for the current and past firmware versions?  Where is it?
The very first page of this topic.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg195143/#msg195143
 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg195143/#msg195143)

Can newer or newest versions be flashed to older hardware versions?
Yes. Flashing erases everything so you're essentially starting with a blank chip.

they do not read capacitor values down to say 4pf.  In fact, one of them will not even read down to 22pf!
Did you calibrate your device? Measuring small cap values is very sensitive. Even the socket will affect your measurement, and probe leads will invalidate it completely.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1269056/#msg1269056 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1269056/#msg1269056)

You can try adding caps in parallel.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1753007/#msg1753007 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1753007/#msg1753007)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tonewheel on January 10, 2019, 04:05:54 pm
Hello all,
I have one of the LCR-T4 testers that looks identical to the one
Dave reviewed: Dave's review (https://youtu.be/7Br3L1B80ow). I just want to check if this one is suitable for flashing with newer firmware. I have a USBTiny to do it with.
Thanks for any help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 10, 2019, 05:45:25 pm
Yep, you can update the firmware. For the k-firmware use mega328_T3_T4_st7565 or mega328_T4_v2_st7565, and for the m-firmware see the Clones file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tonewheel on January 10, 2019, 06:46:23 pm
Thanks very much. The only one I've come across is https://github.com/svn2github/transistortester/tree/master/Software/Markus (https://github.com/svn2github/transistortester/tree/master/Software/Markus). Latest seems to be 1.34m. Is that the 'm' version you mention? I haven't found any other yet.
Thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 10, 2019, 07:28:59 pm
That's right! It's the latest m-firmware. You'll find the k-firmware in the "trunk" directory.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tonewheel on January 10, 2019, 08:00:33 pm
Thank you. Can anyone confirm that the 6 holes next to the crystal are the SPI pins please? I've only just realized that they aren't marked. If they are, has anyone worked out which pin is which?
Thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 11, 2019, 06:56:40 am
Why don't you just buzz it out? It's a beginner level electronics skill.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tonewheel on January 11, 2019, 09:14:44 am
Of course, it didn't even cross my mind. I suppose I'm not a beginner yet, but I hope to be one day.
Cheers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on January 11, 2019, 01:34:11 pm
Please come back here and post the results.
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: tonewheel on January 11, 2019, 01:56:51 pm
Please come back here and post the results.
Thanks
Certainly. At the same angle as the picture I posted above (crystal on the right):
MISO     VCC
SCK       MOSI
RESET    GND

This is the same layout as the connector from the USBtiny, so maybe it's standard, I don't know.

Decided to read the data out of the chip first. Read fuses and EEPROM but got a problem with the flash. Posted avrdude image below. Seemed to be reading but said "flash is empty". I'm reluctant to try and flash it now. I want a backup before I do.

If anyone recognises what's going on there, please let me know.
Many thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on January 11, 2019, 02:58:04 pm
Regardless of battery voltage, I'm starting to get a weird LCD character in some screens on my Hiland DIY M12864 (https://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)
Would re-flashing firmware fix this? or is this typically a fault of the LCD uC controller? - Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 11, 2019, 03:20:37 pm
This is the same layout as the connector from the USBtiny, so maybe it's standard, I don't know.

It's a standard 6-pin ISP.

Decided to read the data out of the chip first. Read fuses and EEPROM but got a problem with the flash. Posted avrdude image below. Seemed to be reading but said "flash is empty". I'm reluctant to try and flash it now. I want a backup before I do.

Despite the firmware being Open Source several clone vendors set the lock bits to prevent flash and EEPROM to be read. If you reset the fuse bits you'll have to program a new firmware anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 11, 2019, 03:32:14 pm
Regardless of battery voltage, I'm starting to get a weird LCD character in some screens on my Hiland DIY M12864 (https://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)
Would re-flashing firmware fix this? or is this typically a fault of the LCD uC controller? - Thanks!

It seems to be the same bad character in all cases. Interesting! If reprogramming doesn't help it could be an issue with the LCD driver.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on January 11, 2019, 05:02:38 pm
I had the same issue with the original firmware the tester came with. Re flashing fixed it.

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on January 11, 2019, 08:49:23 pm
I had the same issue with the original firmware the tester came with. Re flashing fixed it.
Thanks! This thread is really long to read through... could you point me in the right direction for the firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: tonewheel on January 11, 2019, 09:17:15 pm
Quote
Despite the firmware being Open Source several clone vendors set the lock bits to prevent flash and EEPROM to be read. If you reset the fuse bits you'll have to program a new firmware anyway.
Oh okay, thanks for that.
Started reading the readme file for 1.34m. Seems like it may be for those that are building their own devices. Says in the readme:
Quote
this is a playground version with requires an ATmega with 32kB flash at least
Lots of  options, couldn't be sure I'd pick the right ones. Looked in the clones file didn't see anything obvious relating to my one.

I wonder if the 'k' version might be more suitable for me, can't find a link though. Anyone here know where to find it?
Thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 12, 2019, 08:44:09 am
Anyone here know where to find it?

Thanks! This thread is really long to read through... could you point me in the right direction for the firmware?
Page #1
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 12, 2019, 08:56:28 am
Started reading the readme file for 1.34m. Seems like it may be for those that are building their own devices.
Not really. There's no point in building it when you can buy a polished unit for $5. The only difference is you have to configure and compile "M" firmware yourself.

Looked in the clones file didn't see anything obvious relating to my one.
What about "T3/T4"?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on January 12, 2019, 02:30:13 pm
..
Thanks! This thread is really long to read through... could you point me in the right direction for the firmware?
Page #1
Thanks, but I was looking for specific file(s) that user 'mauroh' had used... As I understand, several parts change on different variants and Page #1 did not help. Is there some web page where pcb variants are pictured with brief comments and links to archives at places like mikrocontroller.net?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mauroh on January 12, 2019, 08:31:41 pm
See this  :-+

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1332317/#msg1332317 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1332317/#msg1332317)

Mauro
Title: Re: $20 LCR ESR Transistor checker project
Post by: tonewheel on January 12, 2019, 08:51:23 pm
Looked in the clones file didn't see anything obvious relating to my one.
What about "T3/T4"?
Oh, okay thanks.
Regarding the 'k' version, is this the correct link (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T4_v2_st7565/) for the LCR-T4?

If so, in that post linked to above (for the other questioner) it says: "In any case don't forget the fuses". Is that info in the download?

Thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tonewheel on January 12, 2019, 09:15:57 pm
Downloaded the archive: mega328_T4_v2_st7565. the "last log entry" column on the web page says: "neue chinesische T4 Version". How can I tell if I have the new or old Chinese version please?

Also, no mention of fuses in the Makefile. Never changed fuse settings before, only read about then in a datasheet. What do they need changing to?

Sorry about all the questions, but it's not all obvious if you haven't been following along.
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UKTech on January 12, 2019, 09:53:48 pm
Why not remove your 328 and fit a new one and play with that, worst case scenario just refit the original chip. You'll probably learn more during the process and save yourself lots of typing.  Best of luck. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: tonewheel on January 12, 2019, 09:58:56 pm
Why not remove your 328 and fit a new one and play with that, worst case scenario just refit the original chip. You'll probably learn more during the process and save yourself lots of typing.  Best of luck. :-+
Because it's a tiny surface mount device.
Anyway, I get the hint. Cheers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 13, 2019, 07:54:21 am
Regarding the 'k' version, is this the correct link (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T4_v2_st7565/) for the LCR-T4?

Somewhere near your LCD there will be driver chip. If it's an 'ST7565' then yeah it should work.

Never changed fuse settings before, only read about then in a datasheet. What do they need changing to?

Procedure for flashing firmware (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893)

With the 'M' firmware, just use the T4 options in your makefile, and run make. It will do everything (compile/flash/set fuses etc.) for you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 13, 2019, 10:51:15 am
Downloaded the archive: mega328_T4_v2_st7565. the "last log entry" column on the web page says: "neue chinesische T4 Version". How can I tell if I have the new or old Chinese version please?

There are a few images of the old T4 in Karl-Heinz' documentation (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf)

Also, no mention of fuses in the Makefile. Never changed fuse settings before, only read about then in a datasheet. What do they need changing to?

Please see section 2.10 "Programming of the microcontroller" in Karl-Heinz' documentation.

Sorry about all the questions, but it's not all obvious if you haven't been following along.

Reading the documentation might help. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elbuit on January 14, 2019, 04:14:08 pm
I there.
I was updating the firmware of my chinese version of transistor tester like thins one:
https://yadi.sk/d/yW8xa5NJgUo5z/LCR-T4(T3)NoStripGrid
and I did something wrong that broke the unit.

I usually use an arduino as avrisp to program my unit with @madires or karl firmware but this time I tried with an usbasp device.
I think that I've overwriten fuses with 0x00 because during the writing  operation avrdude asked to back the fuses to original value and I said NO, I know my mistake :-(
So now not usbasp or arduino is capable to read anything, usbasb doesn't detect anything and arduino detects a 0x000000 device, so I think that I've lost my unit.

And I want to buy and affordable unit and I don't know wich is the best chinese option in the market.

Which one should I buy?
If I buy same model I can reuse the box, but I don't know if there are better options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tonewheel on January 14, 2019, 06:09:28 pm
Please see section 2.10 "Programming of the microcontroller" in Karl-Heinz' documentation.
Thanks, I did manage to get the software uploaded in the end. If I can ever stop it nagging me that it's not calibrated I might be able to use it again ha-ha. I've read section 3.3 "Selftest and Calibration" in that PDF several times and still don't quite follow it. It seemed to run though the tests but it always comes up with the nag next time I try and measure something.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2019, 06:15:51 pm
Which one should I buy?
If I buy same model I can reuse the box, but I don't know if there are better options.

I'd buy an AY-AT type clone. But you could also replace the ATmega and maybe recover the old one by a programmer supporting the HV method.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elbuit on January 14, 2019, 07:17:50 pm
Which one should I buy?
If I buy same model I can reuse the box, but I don't know if there are better options.

I'd buy an AY-AT type clone. But you could also replace the ATmega any maybe recover the old one by a programmer supporting the HV method.

Thanks @madires.
I've a atmega m328p in an "arduino micro pro" that woukd fit but I'm not a good solder guy so I think that if I try to desolder an resolder that small smd chip I'll fail and I'll have two broken devices  :'(

So as that devices are inexpensive (from 5€) I decided to buy a new one, and the AY-AT that I've found are quite similar to my LCR T4 broken but have a rotary button and more I/O pins.
I've found some M328 that looks like an AY-AT but most of them are in kit, I've no problem to solder but not smd components so I think that I'll buy an assembled one.
-Have AY-AT more functions than a plain LCR-T4? ie: test zenner diodes, optocoupler, ... (I've found theese option when I compiled your firm)

On the other hand this devices have a TFT color screen that is much better but I supose that those screens consumes more energy than a LCD one.

Thanks.
Edited:
finally I bought an assembled “gm328” device with case that looks identical to this:
https://yadi.sk/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Photo

and I think that matches with AY-AT design.
There is a version called gm328a with smd but I choosed non smd version.
Thanks for your advice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 15, 2019, 02:46:20 pm
The AY-AT clones have a rotary encoder, the basic frequency counter and a voltage divider for measuring external voltages (Zener test without the boost converter). Yes, those images show the classic AY-AT, but there's also a different type called GM328 (ST7565 display).
Title: Re: $20 LCR ESR Transistor checker project
Post by: elbuit on January 15, 2019, 03:48:20 pm
The AY-AT clones have a rotary encoder, the basic frequency counter and a voltage divider for measuring external voltages (Zener test without the boost converter). Yes, those images show the classic AY-AT, but there's also a different type called GM328 (ST7565 display).
I brought a GM328, well description says that is a GM328 but pictures are like the M328 KIT.

It's a really cheap, 11.5€ assembled with case.
I don't want to put any link to a aliexpress but if you look for "On Case Digital ESR Meter GM328 Transistor Tester" you'll find.
I'm looking forward to recive the GM328 to test your firmware
I don't know what I did wrong compiling your firmware but with my tests I wasn't able to use the menu, long press shuts down the LCR-T4.

But this time I won't use USBASP as a programer, I'll use an arduino as avrisp  ;D
Thanks again for your advices.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on January 15, 2019, 04:08:53 pm
Bloody ripper.. case included! what 15 bucks can buy these days (https://www.ebay.com/itm/2017-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator/112489435576?).. almost not worth it to reprogram mine  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: elbuit on January 15, 2019, 05:09:01 pm
Bloody ripper.. case included! what 15 bucks can buy these days (https://www.ebay.com/itm/2017-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator/112489435576?).. almost not worth it to reprogram mine  :-//
Yes, thats true it worths more than you pay and reprogram is the funiest part unless you brick it  |O
I've bought mine in aliexpres (13USD assembled with case) but I don't want to put any link because I haven't received it yet.

I'm a newbie in electronics and for me, this is an amazing tool to test some devices like capacitors (even in-circuit with ESR) or transistors and inductors.
But the most amaizing thing is that it evolves, get better software and more tests and more accurate.
And in my oppinion that kind of devices openned a new paradigm, a open hardware/software to amateur electronics, far from expensive brands that you can't afford if you don't are a professional.
Perhaps in the future there wil be more powerful versions with other inexpensive and powerfull CPU (ie STM32 that uses bluepill) or perhaps no, but the door now is open.
Thanks to all people here that contributes to this project.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 15, 2019, 06:50:02 pm
I don't know what I did wrong compiling your firmware but with my tests I wasn't able to use the menu, long press shuts down the LCR-T4.

Haven't you read the README file? The user interface is a little bit different, i.e. the menu is triggered by two short presses. A long press will power off the tester, as you've learned already.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elbuit on January 15, 2019, 08:10:24 pm

Haven't you read the README file? The user interface is a little bit different, i.e. the menu is triggered by two short presses. A long press will power off the tester, as you've learned already.

You got me   :palm: I’ve read it but not deeply  |O |O |O
I’ve focused in the building part.
My apologies.
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on January 16, 2019, 10:30:55 am
Can someone guide me on how to use the HX1230 lcd display

https://github.com/olikraus/u8g2/issues/469 (https://github.com/olikraus/u8g2/issues/469)
https://www.youtube.com/watch?v=AxcHVq2FNcM (https://www.youtube.com/watch?v=AxcHVq2FNcM)
It's a 96x68 lcd

https://github.com/bitbank2/hx1230 (https://github.com/bitbank2/hx1230)
It is from nokia 1202, has better resolution than nokia 5110 and cheaper
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 16, 2019, 05:33:02 pm
Neither k-firmware nor m-firmware has a driver for HX1230/STE2007 yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Giox040 on January 17, 2019, 11:10:50 am
I own an "AY-AT" ATmega328 with ST7735 color LCD module.
Recently I tried to compile the 1.34M firmware, either using WinAVR, avr-gcc-8.2.0 and Atmel Studio 7.
I get a warning, is it normal ?:

Quote
tools.c: In function 'Cap_Leakage':
tools.c:3302:9: warning: 'U1' may be used uninitialized in this function [-Wmaybe-uninitialized]
         Display_Value(U1, -3, 'V');          /* display voltage */
         ^~~~~~~~~~~~~~~~~~~~~~~~~~

Another problem is that I can not make everything I want in the chip .... maybe I ask too much from this small tool.
Basically I would need to be able to test the goodness of the components but I do not need to measure resistance, impedance,
capacity, read or generate frequencies, because I own other equipment.

But I wish I could test loss and ESR, IR detector and IR transmitter, Zener.
 
Below is my config.h, what could I remove to make us stay SW_IR_TRANSMITTER?

Code: [Select]
/* config.h  */

/* source management */
#define CONFIG_H

/*  rotary encoder for user interface */
#define HW_ENCODER
#define ENCODER_PULSES   4
#define ENCODER_STEPS    20

/*  Typical voltage of 2.5V voltage reference (in mV) */
#define UREF_25           2495

#define HW_ZENER

#define HW_FREQ_COUNTER_BASIC  // <<<

#define FREQ_COUNTER_PRESCALER   16   /* 16:1 */

#define SW_PWM_SIMPLE

#define SW_INDUCTOR

#define SW_ESR

#define SW_ENCODER

//#define SW_SQUAREWAVE  // <<<

#define SW_IR_RECEIVER

//#define SW_IR_TRANSMITTER // <<<

#define SW_IR_EXTRA // <<<

#define SW_OPTO_COUPLER // <<<

#define SW_UJT

#define SW_PROBE_COLORS

//#define SW_SERVO

#define SW_DS18B20 // <<<

#define SW_CAP_LEAKAGE

/* ************************************************************************
 *   Makefile workaround for some IDEs
 * ************************************************************************ */
#ifndef OSC_STARTUP
  #define OSC_STARTUP    16384
#endif

#define UI_ENGLISH

#define CYCLE_DELAY      3000

#define CYCLE_MAX        100    // 5

#define BAT_DIVIDER

#define BAT_R1           10000
#define BAT_R2           3300

#define BAT_OFFSET       100  // 290  misurato 7,51 - 7,46

#define BAT_WEAK         7400

#define BAT_LOW          6400

#define SAVE_POWER

#define UREF_VCC         5001

#define UREF_OFFSET      0

#define R_LOW            680
#define R_HIGH           470000

#define RH_OFFSET        350

#define R_ZERO           20

#define CAP_WIRES        2

#define CAP_PROBELEADS   9

#define CAP_DISCHARGED   2

#define CAP_FACTOR_SMALL      0      /* no correction */
#define CAP_FACTOR_MID        -40    /* -4.0% */
#define CAP_FACTOR_LARGE      -90    /* -9.0% */

#define ADC_SAMPLES      25

#define CPU_FREQ    F_CPU

#if defined(__AVR_ATmega328__)

  #include "config_328.h"

#elif defined(__AVR_ATmega324P__) || defined(__AVR_ATmega644__) || defined(__AVR_ATmega1284__)

  #include "config_644.h"

#else
  #error <<< No or wrong MCU type selected! >>>
#endif


/*  ADC clock  */
#if CPU_FREQ == 20000000
  /* 20MHz MCU clock */
  #define ADC_FREQ    156250
#else
  /* all other MCU clocks */
  #define ADC_FREQ    125000
#endif


/* 1MHz/250kHz */
#if CPU_FREQ / ADC_FREQ == 4
  #define ADC_CLOCK_DIV (1 << ADPS1)
#endif

/* 1MHz/125kHz 2MHz/250kHz */
#if CPU_FREQ / ADC_FREQ == 8
  #define ADC_CLOCK_DIV (1 << ADPS1) | (1 << ADPS0)
#endif

/* 2MHz/125kHz 4MHz/250kHz */
#if CPU_FREQ / ADC_FREQ == 16
  #define ADC_CLOCK_DIV (1 << ADPS2)
#endif

/* 4MHz/125kHz 8MHz/250kHz */
#if CPU_FREQ / ADC_FREQ == 32
  #define ADC_CLOCK_DIV (1 << ADPS2) | (1 << ADPS0)
#endif

/* 8MHz/125kHz 16MHz/250kHz */
#if CPU_FREQ / ADC_FREQ == 64
  #define ADC_CLOCK_DIV (1 << ADPS2) | (1 << ADPS1)
#endif

/* 16MHz/125kHz 20MHz/156.25kHz */
#if CPU_FREQ / ADC_FREQ == 128
  #define ADC_CLOCK_DIV (1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0)
#endif


#define C_ZERO           CAP_PCB + CAP_WIRES + CAP_PROBELEADS

#define MCU_CYCLES_PER_US     (CPU_FREQ / 1000000)

#define MCU_CYCLES_PER_ADC    (CPU_FREQ / ADC_FREQ)

#define MCU_CYCLE_TIME        (10000 / (CPU_FREQ / 1000000))

/* additional keys */
/* rotary encoder, increase/decrease push buttons or touch screen */
#if defined (HW_ENCODER) || defined (HW_INCDEC_KEYS) | defined (HW_TOUCH)
  #define HW_KEYS
#endif

/* options which require additional keys */
#ifndef HW_KEYS

  /* PWM+ */
  #ifdef SW_PWM_PLUS
    #undef SW_PWM_PLUS
    #define SW_PWM_SIMPLE   
  #endif

  /* squarewave generator */
  #ifdef SW_SQUAREWAVE
    #undef SW_SQUAREWAVE
  #endif

  /* Servo Check */
  #ifdef SW_SERVO
    #undef SW_SERVO
  #endif

#endif


/* options which require a MCU clock >= 8MHz */
#if CPU_FREQ < 8000000

  /* ESR measurement */
  #ifdef SW_ESR
    #undef SW_ESR
  #endif

  /* old ESR measurement */
  #ifdef SW_OLD_ESR
    #undef SW_OLD_ESR
  #endif

#endif


/* SPI */
#if defined (SPI_BITBANG) || defined (SPI_HARDWARE)
  #define HW_SPI
#endif


/* I2C */
#if defined (I2C_BITBANG) || defined (I2C_HARDWARE)
  #define HW_I2C
#endif


/* TTL serial */
#if defined (SERIAL_BITBANG) || defined (SERIAL_HARDWARE)
  #define HW_SERIAL
#endif

/* VT100 display driver disables other options for serial interface */
#ifdef LCD_VT100
  #ifdef UI_SERIAL_COPY
    #undef UI_SERIAL_COPY
  #endif
  #ifdef UI_SERIAL_COMMANDS
    #undef UI_SERIAL_COMMANDS
  #endif 
#endif

/* options which require TTL serial */
#ifndef HW_SERIAL
  #ifdef LCD_VT100
    #undef LCD_VT100
  #endif
  #ifdef UI_SERIAL_COPY
    #undef UI_SERIAL_COPY
  #endif
  #ifdef UI_SERIAL_COMMANDS
    #undef UI_SERIAL_COMMANDS
  #endif
#endif

/* options which require TTL serial RW */
#ifndef SERIAL_RW
  #ifdef UI_SERIAL_COMMANDS
    #undef UI_SERIAL_COMMANDS
  #endif
#endif


/* OneWire: probe leads prevail */
#ifdef ONEWIRE_PROBES
  #undef ONEWIRE_IO_PIN
#endif
#ifdef ONEWIRE_IO_PIN
  #undef ONEWIRE_PROBES
#endif

/* options which require OneWire */
#if ! defined (ONEWIRE_PROBES) && ! defined (ONEWIRE_IO_PIN)
  #ifdef SW_DS18B20
    #undef SW_DS18B20
  #endif
#endif


/* touchscreen */
#ifdef TOUCH_PORT
  #define HW_TOUCH
#endif


/* LCD module */
#ifdef LCD_CONTRAST
  #define SW_CONTRAST
#else
  #define LCD_CONTRAST        0
#endif


/* color coding for probes requires a color graphics display */
#ifdef SW_PROBE_COLORS
  #ifndef LCD_COLOR
    #undef SW_PROBE_COLORS
  #endif
#endif


/* component symbols for fancy pinout */
#if defined (SYMBOLS_24X24_H)
  #define SW_SYMBOLS
#endif
#if defined (SYMBOLS_24X24_HF) || defined (SYMBOLS_30X32_HF) || defined (SYMBOLS_32X32_HF)
  #define SW_SYMBOLS
#endif
#if defined (SYMBOLS_24X24_VFP)
  #define SW_SYMBOLS
#endif
#if defined (SYMBOLS_24X24_VP_F)
  #define SW_SYMBOLS
#endif

/* symbols require graphic display */
#ifdef SW_SYMBOLS
  #ifndef LCD_GRAPHIC
    #undef SW_SYMBOLS
  #endif
#endif


/* frequency counter */
#if defined (HW_FREQ_COUNTER_BASIC) || defined (HW_FREQ_COUNTER_EXT)
  #define HW_FREQ_COUNTER
#endif


/* IR detector/decoder: probe lead based decoder prevails */
#ifdef SW_IR_RECEIVER
  #undef HW_IR_RECEIVER
#endif
#ifdef HW_IR_RECEIVER
  #undef SW_IR_RECEIVER
#endif

/* ************************************************************************
 *   EOF
 * ************************************************************************ */


Thank You very much for any answer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on January 17, 2019, 11:20:37 am
I own an "AY-AT" ATmega328 with ST7735 color LCD module.
Recently I tried to compile the 1.34M firmware, either using WinAVR, avr-gcc-8.2.0 and Atmel Studio 7.
I get a warning, is it normal ?:

Quote
tools.c: In function 'Cap_Leakage':
tools.c:3302:9: warning: 'U1' may be used uninitialized in this function [-Wmaybe-uninitialized]
         Display_Value(U1, -3, 'V');          /* display voltage */
         ^~~~~~~~~~~~~~~~~~~~~~~~~~


https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1879004/#msg1879004 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1879004/#msg1879004)

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1879076/#msg1879076 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1879076/#msg1879076)

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 17, 2019, 03:15:02 pm
Another problem is that I can not make everything I want in the chip .... maybe I ask too much from this small tool.
Basically I would need to be able to test the goodness of the components but I do not need to measure resistance, impedance,
capacity, read or generate frequencies, because I own other equipment.

The resistance and capacitance measurements are essential and can't be disabled. But you can disable PWM (SW_PWM_SIMPLE) and the basic frequency counter (HW_FREQ_COUNTER_BASIC). If the firmware is still too large go for a tester with an ATmega 644 (look for "transistor tester M644" for example).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stinger on January 19, 2019, 12:25:29 am
Hello,

I received acrylic case for my LCR T4 V2.68 tester. But, Case are to short for 2,5mm... :-[

Are V2.68 tester with chinese caracters have differents dimension than generic ?

Mine :
(https://www.makerfabs.com/image/cache/makerfabs/LCR-T4%2012864LCD%20ESR%20SCR%20Meter%20Transistor%20Tester/LCR-T4%2012864LCD%20ESR%20SCR%20Meter%20Transistor%20Tester_1-1000x750.JPG)

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 19, 2019, 03:47:23 pm
I've seen T4 clones with slightly different PCBs. So my advice would be to buy a tester which includes the case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elbuit on January 19, 2019, 04:00:46 pm
Hello,

I received acrylic case for my LCR T4 V2.68 tester. But, Case are to short for 2,5mm... :-[

Are V2.68 tester with chinese caracters have differents dimension than generic ?


As far as I know there are no generic or standard dimensions.
I bought a LCR T4 with case and it fits perfectly, but as there are some diferent versions of transistor tester there are diferent kind of cases.

You can build a case yourself using or even screw it to a small plastic or wood rectangle.
Title: Re: $20 LCR ESR Transistor checker project
Post by: E440Qf on January 23, 2019, 05:21:56 pm
where can i find the english firmware precompiled (.hex and .eep) for GM328A?
i've been searching for hours |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 23, 2019, 07:58:05 pm
Did you check page 1 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg195414/#msg195414)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on January 24, 2019, 11:10:20 pm
Finally  :)
1 of 2 working with just the most basic circuits for power and startup.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GregDunn on January 25, 2019, 02:41:16 am
Just got one of the AY-AT marked testers and wanted to test it out thoroughly.  I didn't have a 9V battery clip to mate with the device (it only has a barrel connector), so I looked around and found a 9VDC power supply with the proper polarity.  But before plugging it into the device, I measured the voltage and it was almost 14VDC!

This spec is not visible in the manual, and a 15-20 minute search of this thread didn't come up with the desired info, so: how much voltage is safe to put into one of these without blowing it up?  I know most wall warts will drop substantially when loaded, but this one is designed for a much heavier load, so I don't want to blindly try it out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on January 25, 2019, 04:21:13 am
any transformer based psu will be way over without a load.
the max input of the ay-at is going to be down to the voltage regulator - get a datasheet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GregDunn on January 25, 2019, 08:53:45 am
Looks like the max regulator voltage is about 13V - and the PSU voltage is 13.5 even with a load comparable to the tester.    :(  Time to hunt for another one...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 25, 2019, 12:41:36 pm
The AY-AT clones have an HT7550 LDO usually (24V max). We have also to consider the power control circuitry with the BJTs and the LED since they are powered directly. 14V should be ok if the LDO can handle that voltage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GregDunn on January 25, 2019, 05:25:13 pm
Mine didn't come with a schematic and I didn't want to tear it apart to try and decipher the markings, so I just bodged an adapter and fed it 9VDC from one of my lab supplies.

Unfortunately, it looks like mine has a problem; when trying to set any of the parameters or run any of the routines, it hangs.  And the default "test on startup" always returns a fail - i.e., no part.  Looks like this one goes back.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on January 26, 2019, 05:50:35 pm
Mine didn't come with a schematic...
https://youtu.be/mRMRtrzh6rI
Or
https://github.com/Upcycle-Electronics/AVR-Transistor-Tester
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 26, 2019, 08:40:47 pm
Finally  :)
1 of 2 working with just the most basic circuits for power and startup.

Plug-n-play ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on January 27, 2019, 03:30:56 am
Plug-n-play ;D
Yeah I got 1.34m working on it today. It's nice to be able to try anything I want without much planning or CAD. I just need perfboard, wire, and a note pad to sketch on.
  It all fits into a bench enclosure. The test pad and rotary encoder are just there for stand alone testing. I still have a bunch of stuff to figure out, but I'm having fun. I have all of my HD44780 displays working in parallel with both firmwares, and I'm currently working on a ST7920 adapter that will test that display with parallel and serial. I may hook up the KS0108 on this board too.
 I'm super confused why KH's makefiles don't include 644/1284 options for all of the displays and stuff but I just need to test some stuff out before going into that...or I'm going to suck it up and build a 1280 board out of madness...

  One question. Who has the VT100 setup? I don't think I've seen that before. Are they running it on an Emulator or the real DEC'ing deal? (Sorry if I've overlooked this)
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on January 27, 2019, 04:27:25 am
Looks like the max regulator voltage is about 13V - and the PSU voltage is 13.5 even with a load comparable to the tester.    :(  Time to hunt for another one...
Just preload the output with about 100mA and the output will drop close to 9V, 100Ω 2W resistor will do it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on January 27, 2019, 07:23:00 am
Unfortunately, it looks like mine has a problem; when trying to set any of the parameters or run any of the routines, it hangs.  And the default "test on startup" always returns a fail - i.e., no part.  Looks like this one goes back.

Since yours came assembled, you might give the board a thorough clean to get all the shmutz off. Then, check for the usual solder bridges, dry or cracked joints, etc. Also verify that the microcontroller is getting the correct voltage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: E440Qf on January 27, 2019, 04:51:12 pm
yes but i can't figure out which one is the right one...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 27, 2019, 04:52:28 pm
I'm super confused why KH's makefiles don't include 644/1284 options for all of the displays and stuff but I just need to test some stuff out before going into that...or I'm going to suck it up and build a 1280 board out of madness...

You'll find the port and pin assignments for the display in config.h. Search for HW_LCD and make sure that you edit the 644 section. BTW, the k-firmware doesn't support hardware SPI.

One question. Who has the VT100 setup? I don't think I've seen that before. Are they running it on an Emulator or the real DEC'ing deal? (Sorry if I've overlooked this)

No need for a classic DEC terminal, most terminal programs support VT100.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 27, 2019, 04:59:28 pm
yes but i can't figure out which one is the right one...

Have you tried mega328_GM328? ;) Or post a picture of your tester and we might be able figure out the model.
Title: Re: $20 LCR ESR Transistor checker project
Post by: E440Qf on January 27, 2019, 05:09:10 pm
GM328A, does the gm320 firmware works?
and which fuse config should i use?
Thanks in advance
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 27, 2019, 05:12:34 pm
That one looks like an AY-AT clone. Please try mega328_color_kit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: E440Qf on January 27, 2019, 05:20:13 pm
which fuse configuration?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 27, 2019, 05:28:24 pm
Most likely you can keep current fuse settings (otherwise: make fuses). Maybe you have to clear the lock bits as some clone manufacturers like to set them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: LarryS on January 27, 2019, 06:20:21 pm
This is my first message; so if I do something wrong, please be....

My V 2.68 came with the proper screws and I had no trouble assembling it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on January 29, 2019, 11:37:00 pm
1.34m
config_644.h
ST7920 4 bit parallel
change line:
#define LCD_EN1  PB3
to
#define LCD_EN   PB3

:)

It looks like my 7920 has seen better days. I triple checked my wiring, but nope. I managed to make and upload the code though. AVRDude shot out an error for an unrecognized function or something like that. Just removing the "1" fixed it. Without the screen working I just tested an LED and it runs the whole test routine (on top of the fact the MCU power control still works). The same adapter board also has a Nokia header and that one works fine too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 30, 2019, 12:15:39 pm
The new m-firmware version is progressing, including several bug fixes and improvements. I'm considering a change of the capacitance zero offset (for PCB, probe leads, etc.). Currently the firmware uses an average value for all probe pairs, and the idea is to go for probe pair specific values. The reason for this idea is that I've seen some small differences of a few pF for some hardware. What's your opinion on this?

The second topic is about displays. Some support an SPI 9 bit mode, i.e. the D/C (data/command) signal is part of the SPI data (1st bit) instead of a dedicated line. Since the ATmega's hardware SPI does only bytes, the 9 bit mode will be available just for bit-bang SPI. I already have added the code and extended the SSD1306 driver. Some users requested a driver for the Nokia 1202 display (STE2007/HX1230) which seems to require the 9 bit mode, and also a driver for the ST7036. If you like to support the project by sponsoring display samples please contact me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on January 31, 2019, 04:57:41 am
..."the idea is to go for probe pair specific values. The reason for this idea is that I've seen some small differences of a few pF for some hardware. What's your opinion on this?
  I think it's a great idea.
   I haven't tried to calibrate my new design yet with either fw, but I'm looking forward to exploring this down to the code and functions level as a learning exercise. I also would like to try to test and understand the resistance of the internal port and the comparator offset figures. I'm sure I need to go read an app note or two about that before going into detail.

  I picked up an old Keithley 197 5.5 digit DMM. I still need to get a proper LCR meter to really contribute useful info though.

  The more displays the better. I'm trying to test out one that was sold as an ILI9341 right now but I think it's a fake as I've read more. I ordered a different one last night along with a couple other options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 01, 2019, 06:47:51 pm
1.34m
config_644.h
The ST7920 SPI configuration is not pulling the Reset pin high. I have it set to the default PB2 and it just stays low. I checked ST7920.c and the function LCD_BusSetup has the lines:

#ifdef LCD_RESET
  Bits |= (1<< LCD_RESET);
#endif

  The same routine is applied to LCD_CS. CS is assigned to pin PB4 and it is being pulled high like it should be. Neither pin is actually required. Both of them can connect to a 10k pullup resistor to Vcc. The only required MCU connections are Data and Clock. Power, Ground, Backlight, Chip Select, Reset, and the Parallel or Serial Bit (PSB) can get connected directly.
  I would recommend adding this in the comments. 'The user can add a 10k pullup to CS, RST and comment out these connections to the MCU in the configuration.' You could also make a note that the PSB pin must be tied low for serial mode and high for parallel. IMO it would be a helpful reminder for troubleshooting.

 BTW thanks for getting me motivated to try out Sigrok software and a little 24MHz 8 channel clone logic analyzer :)
  I took apart the broken ST7920 and managed to get it kinda working...enough to troubleshoot this stuff, and figure out what was going wrong. I even quadruple checked my wiring by bypassing my little adapter board just to be sure. I'm not sure if this is also a problem with the parallel version but it wasn't working for me either yesterday. I figured it was just my crappy LCD but I got the LCD working with an Arduino test setup and SPI so I know the screen mostly works, there are just a few dead lines in the matrix. (Short story: don't take these things apart...me=big dummy)
-Jake
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 01, 2019, 07:54:45 pm
That's just for setting the pin to output mode. A few lines below you'll find:
Code: [Select]
  #ifdef LCD_RESET
    /* disable reset */
    LCD_PORT |= (1 << LCD_RESET);       /* set /RESET high */
  #endif
... which sets the pin high (no reset).

The reset is performed in the function for initializing the display:
Code: [Select]
  #ifdef LCD_RESET
  /* reset display */
  LCD_PORT &= ~(1 << LCD_RESET);        /* set /RES low */
  wait10us();                           /* wait 10µs */
  LCD_PORT |= (1 << LCD_RESET);         /* set /RES high */
  MilliSleep(1);                        /* wait 1ms */
  #endif
This creates a low pulse of 10µs to reset the display. It's done only once after powering on.

The comments for LCD_RESET and LCD_CS include an "optional" as hint already. However, I could add a note about using pull-up/down resistors in the README as help for beginners.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 01, 2019, 10:06:13 pm
The comments for LCD_RESET and LCD_CS include an "optional" as hint already. However, I could add a note about using pull-up/down resistors in the README as help for beginners.
Thanks. I wasn't sure what the line I quoted was for exactly. Now it makes more sense.

...and after looking at the logic analyzer I see I was making a mistake reading it... (me=big dummy)...sorry...

  On a whole different note...

AY-AT ST7735 LCD Fix
   If anyone has the same junky 1.8" TFT ST7735 display that comes with the AY-AT clones, let's fix a problem here...
Do you have problems with the screen? Text appears in different locations, in multiple colors, with random junk on the screen, and or sometimes it just doesn't work at all or white screens? Then here is your fix.

If you look at the back of your display module you will find it has a CD4050 and a small voltage regulator. What you will not see is any power supply filter capacitors. This is why your display sucks. It (probably) isn't the firmware causing this. It's just a terrible LCD module design. All you need to do is scrape off the solder mask on the regulator's input trace along with the ground plane directly adjacent. I added a 4.7uF and a 100nF ceramic capacitor just beside the input for the regulator. I also added a 100nF ceramic capacitor to pin 1 of the CD4050 (and ground plane beside it). All of these are 0805. I also added a 0603 100nF capacitor directly to the 2 power pins of the LCD flat flex. That fixed the problem as shown below.

*This is the screen from my AY-AT clone but tested with Markus's firmware and on my board design. The fix is still applicable. I haven't used my AY-AT much because of these issues with the screen. This should greatly improve the use of this screen anywhere.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 04, 2019, 01:22:20 am
Hack a T3 Clone Display
   So I've been playing around with a bunch of different stuff... Basically, I had a little T3 tester for awhile (along with the two kit clones). Of the 3 clones the T3 has the best SMD component test pad configuration by far. I have found myself using it the most because of that test pad. However the LCD got damaged. I'm not even sure how. I just noticed a tiny chip in the glass near the flat flex and the display quit working. Okay, no problem, a new one is cheap....A month and a half later I get the replacement... The display doesn't work  :scared: I tested the programming by updating it. Checked connections and while trying to take it apart to resolder the flat flex, I discovered it was already pre-broken for me.
  ...anyways... I took the display off of my Little t tester clone. That's the smaller version of the ST7565 LCD. I mapped the connections and tried the T3 firmware just to see what would happen. Nothing of course. After switching the firmware over the KH`s "mega328_st7565_kit" it worked great. I didn't make changes to the tester option settings. I always have to recompile everything to use the USBasp, but that's all I changed. I chose this display because it is cheaply available if I want to just get a spare for each tester.

  You'll see a few mods here both past and present.
1.) I try to swap out the ZIF socket for headers on all clones, because I've learned the ZIF sockets get worn out quickly when all the slots are not used or you test a lot of stuff with thicker pins.
2.) I have added a 2p3t switch that I have configured for quick manual calibration. This can be in an open configuration, can short out all 3 test pins, or connect a film cap to 1 and 3.
3.) I added a stereo audio jack and made my own test clip leads that plug into it,
4.) I added 4x 10mm standoffs to the OEM locations, but also added a 5th standoff near the SMD test pad. This is probably the most significant mod worth doing on this tester. That makes the SMD pad much nicer to use.

  The last bit of rambling I'll do here is just to add the reminder, the LCD backlight for the T3 tester is the required LED for the power management control circuit. If you take things apart for doing mods be sure you add an LED in place of the backlight to test anything. Here are a few pics of mods ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 04, 2019, 11:23:06 pm
Spare LCR T3 Clone Spec Test
 ...because I have a spare and you must remove stuff to measure the 470K sense resistors.
Test Voltage   
    9.369V (battery)
Voltage Regulator
    5.032V (78L05)
Voltage Reference
    2.500V (TL431)
LCD Power (could easily be the problem killing a lot of LCDs)
    Open Circuit
        4.535V
    With 10k Resistor Dummy Load
        3.889V
Sense Resistors
  R1  681.27R
  R2  468,470R
  R3  679.43R
  R4  474,810R
  R5  679.05R
  R6  472,250R

Deviation
  R1  +0.19%
  R2   -0.33%
  R3   -0.08%
  R4  +1.02%
  R5   -0.14%
  R6  +0.48%
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 04, 2019, 11:46:10 pm
Maybe I missed something, but why are you posting all this?

Why do we need images of your measurements?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 05, 2019, 01:01:48 am
Maybe I missed something, but why are you posting all this?

Why do we need images of your measurements?
Are you having a bad day?

  Personally I was curious about the tolerance of the resistors used on the LCR T3 given the price range and the 3 digit markings that generally indicate a low tolerance. If you try to test these in circuit you will find it impossible to test the 470k's on any device with the microcontroller permanently mounted. I haven't seen anyone post this. Perhaps I missed it, who knows. These specs are better than both of my other kit clones. I certainly didn't expect the cheapest one to have the better specs. Did you? The one schematic that exists for this clone is also a different hardware revision with different connections. There have been many people that have had screens fail. I haven't seen anyone mention the open circuit voltage of the LCD power supply. I find it interesting that the 78L05 I tested here is within the same specs as the MCP1702-5002. The TL431 here is spot on and, in this instance, more accurate than my lm4040's. If I had known all of this I probably would have just gotten a T3 in the first place.
  I have a much better version of the project to play with. I'm just sharing the kind of info I would have liked to have known. Perhaps I'm wasting my time, but those are a few reasons why.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 05, 2019, 01:11:01 am
Are you having a bad day?
Nope. Simple question. Are you?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 05, 2019, 01:34:00 am
I find it interesting that the 78L05 I tested here is within the same specs as the MCP1702-5002

Voltage Regulator
    5.032V (78L05)

This is measured with your AN8009? 0.5% +3 meter.
so actual voltage could be up to 5.060V. That is a tolerance of 1.2%

The MCP1702 has a tolerance of 0.4%
Title: Re: $20 LCR ESR Transistor checker project
Post by: spiderb on February 05, 2019, 04:26:43 pm
i myself think that what makes this topic interesting is the vast amount of details available
if something was not of interset to me then i wont read it
i certainly would not complain as it could just what someone else needs

bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 05, 2019, 05:56:09 pm
   I'm no expert, just a self proclaimed student of this project. I try to show my work so that others can (kindly) correct me when I inevitably write something stupid.

@Madires
   Is it possible to build an ATmega328 version with HW SPI available for the display if the test resistor port is swapped in your firmware? Would that speed up the display refresh rate significantly for the tft options?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2019, 07:07:57 pm
That should be possible when you also move the power control to the other port. And yes, the hardware SPI is much faster and will speed up the display output, especially for color displays.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rocknroller on February 06, 2019, 05:10:56 am
Can someone recommend a specific pre-made tester that I can just purchase now that has the latest firmware, or close. I really don't have the time to build from a kit and I don't want to have to download firmware etc. Just want to buy one and start using it. Color is nicer, but prefer more flexibility in features/accuracy over that. Mostly using for testing transistors, including JFETs and related (maybe an occasional germanium or darlington). Also ESR for caps, though I have other esr testers could be used so less important. Transistir the focus. thanks for any advice and/or link to something I can get now. I see TC1 and T6 and T7 on ebay, not clear which is later/better or if there are better choices.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 06, 2019, 05:40:39 am
Sellers don't tell you the firmware version, but you can bet it's old.

This is a community project, not a commercial product. You might be more interested in Bob Parker products or something similar.
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on February 06, 2019, 06:00:10 am
Not that I follow this topic that closely but sometimes people lose sight of what these devices are. An excellent Cheap, Simple and reasonably accurate toy to have in your collection of gear. If you think they will become a miracle device by getting the latest firmware upgrade to a $7-15 item you are wrong.

The extreme lengths and work that continues to go on with these is way OTT but in a good way :-+

Upgrading firmware on mine is a non issue it just works and it sits in my on site bag powered by a 2S LiPo with a few other meters that won't do what it does. I have posted photos of mine ages ago but not with the 2S300 LiPo fitted into the HDD case it is shoehorned into.

Buy one and be happy  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 07, 2019, 03:58:29 am
External drive case. That's nifty, bean.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 07, 2019, 05:06:50 am
@rocknroller
  I don't have the more expensive clones. I recall there are a few problems with some of the more advanced clones as far as their ability to be flashed with newer firmware. All clones are pirate hardware. No one is too upset about it, but I know it's a minor irritation to some. The firmwares are usually modified for whatever reason. The Devs have reversed most of the common clones well enough to support the hardware various configuration.
   All that said, I think Nick L was selling some of his version 2 testers over on the Russian forum at some point. I don't know if that's still happening. As far as I onow that's the only simi-official complete hardware that has ever been sold. All the clones I have came with their own issues. The T3/T4 at $5-$7 is about as disposable as most of the clone designs. The actual OS project is centered around creating your own hardware from scratch. I had no intention of making my own a year ago, but it's the only way to get the proper specs and hardware configuration.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 07, 2019, 05:16:14 am
making my own a year ago, but it's the only way to get the proper specs and hardware configuration.

It's ONE way. Most people find it easier to start with a clone and modify it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on February 07, 2019, 06:08:14 am
'Proper Specs' is questionable given the components typically used on these. They are not well defined typically and even improving on the absolute 'accuracy' or tolerances and quality of the components without known equipment and standards to compare them to makes this fairly pointless. If you have those standards very doubtful you will be using one of these to get 'accurate' measurements  ;)

The use of the word 'clone' in this discussion is also pointlessly diminutive of available options and designs as there is so many deviations since the original hardware and software first came into being. What is a clone and what isn't a clone of what actual version exactly?

If you want 'proper specs' buy a 'proper meter' otherwise be happy with what they are :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 07, 2019, 06:16:01 am
Read the documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on February 07, 2019, 06:16:42 am
For 'which' design?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 08, 2019, 12:54:19 am
This is a link to a compressed GIMP .xcf file on my google drive that contains the full retrace of the T3 tester.
https://drive.google.com/file/d/1U6cCFLlBwzlxoqhO3nLSMuxnIa4emzOa/view?usp=sharing
  Be aware this is 53.3mb in a zip file, and is 97.3mb uncompressed. This is over 180 layers on gimp. I tried gimp for a change as I can't use the app I used in the past to make the retrace videos for the AY-AT and Little t kits. I wanted to try a couple simple things in gimp with as you can see with attached images.
Title: Re: $20 LCR ESR Transistor checker project
Post by: james3 on February 08, 2019, 01:02:39 pm
Hello anyone,
I'd like to buy one of these Component Tester Identifier KIT DIY, but there are too many version and I'm bit confused

Could you please suggest me which one is the best ? Maybe with the best firmware ?

Thanks
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 09, 2019, 03:04:21 am
Can someone recommend a specific pre-made tester that I can just purchase now that has the latest firmware, or close. I really don't have the time to build from a kit and I don't want to have to download firmware etc. Just want to buy one and start using it. Color is nicer, but prefer more flexibility in features/accuracy over that. Mostly using for testing transistors, including JFETs and related (maybe an occasional germanium or darlington). Also ESR for caps, though I have other esr testers could be used so less important. Transistir the focus. thanks for any advice and/or link to something I can get now. I see TC1 and T6 and T7 on ebay, not clear which is later/better or if there are better choices.

Hello anyone,
I'd like to buy one of these Component Tester Identifier KIT DIY, but there are too many version and I'm bit confused

Could you please suggest me which one is the best ? Maybe with the best firmware ?

Thanks
 

See: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2119831/#msg2119831 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2119831/#msg2119831)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pierreraymondrondelle on February 10, 2019, 12:10:59 pm
Hi,
I just repaired two NB2L li-ion batteries from my Canon cam that weren't charging at all. OTOH, I'm tired to buy €€ 9V batteries, so I decided to give them a second chance with a 9V powered device. The NB2L are rated 7.4V and I have a spare charger.

The LCR tester was a good candidate. I did some measurements on mine, it detects a weak battery at 7.4V and works fine above this value. However 7.4V looks a bit high regarding the ver 1.12k user's manual that says 0.8V above 5.4. Any clue ?

So far so good ! The batteries are within the acceptable range. If the tester keeps working satisfactorily, I'll finally get rid of these medieval 9V batteries !
regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 10, 2019, 03:04:33 pm
A 9V battery run down to 7V isn't able to provide sufficient current for the tester any more. You can change the voltage thresholds in the Makefile (k-firmware) or in config.h (m-firmware) in case of using a LiIon/LiPo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 3roomlab on February 10, 2019, 07:25:02 pm
I was looking at the github schematic. the same exact firmware for 28pin is used w/o any changes in the 40pin? (or maybe the better Qn, how many versions are there in the wild? I could see special version for specific LCDs, but for 40pin?)
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on February 10, 2019, 10:41:11 pm
Hi,
I just repaired two NB2L li-ion batteries from my Canon cam that weren't charging at all. OTOH, I'm tired to buy €€ 9V batteries, so I decided to give them a second chance with a 9V powered device. The NB2L are rated 7.4V and I have a spare charger.

The LCR tester was a good candidate. I did some measurements on mine, it detects a weak battery at 7.4V and works fine above this value. However 7.4V looks a bit high regarding the ver 1.12k user's manual that says 0.8V above 5.4. Any clue ?

So far so good ! The batteries are within the acceptable range. If the tester keeps working satisfactorily, I'll finally get rid of these medieval 9V batteries !
regards

Mine has been fine on 2S LiPo's (8.4V fully charged) for nearly a year and the low voltage of 7.4 isn't an issue just a reminder with plenty of safety to charge them as the power consumed/test is tiny so losing the last of the useful battery charge isn't an issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on February 10, 2019, 11:53:54 pm
Not particularly accurate but still in the ballpark playing with my newly arrived doorstop.

Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 11, 2019, 12:31:57 am
What's with the vertical bar characters in the middle of the readings?
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on February 11, 2019, 12:38:09 am
What's with the vertical bar characters in the middle of the readings?

Special Chinesium non blanked LCD I would reckon. 1+1 = ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 11, 2019, 12:50:26 am
Ah, leftover pixels, eh? 1+1 = || ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: nation on February 11, 2019, 03:55:05 am
Sorry for the newb question.

I have had 3 of these, 2 bought a year ago and I just had another delivered today, and none of them work with an external 9v power supply. If I hook up a battery clip and connect external power via the battery clip it works. I thought this might have been an assembly or design fault that may be fixed in later runs but it's there with the new unit also.

What's possibly going on here that an external power supply plugged directly in won't work? And how do I fix it.

This is the tester I have

https://www.ebay.com.au/itm/GM328A-Component-Tester-Multifunctional-Meter-Graphic-Transistor-Tester-W1/352521940684?hash=item5213f1eecc:g:zy8AAOSwGD1b9TKZ:rk:1:pf:1&frcectupt=true (https://www.ebay.com.au/itm/GM328A-Component-Tester-Multifunctional-Meter-Graphic-Transistor-Tester-W1/352521940684?hash=item5213f1eecc:g:zy8AAOSwGD1b9TKZ:rk:1:pf:1&frcectupt=true)
Title: Re: $20 LCR ESR Transistor checker project
Post by: PedroDaGr8 on February 11, 2019, 04:35:11 am
Sorry for the newb question.

I have had 3 of these, 2 bought a year ago and I just had another delivered today, and none of them work with an external 9v power supply. If I hook up a battery clip and connect external power via the battery clip it works. I thought this might have been an assembly or design fault that may be fixed in later runs but it's there with the new unit also.

What's possibly going on here that an external power supply plugged directly in won't work? And how do I fix it.

This is the tester I have

https://www.ebay.com.au/itm/GM328A-Component-Tester-Multifunctional-Meter-Graphic-Transistor-Tester-W1/352521940684?hash=item5213f1eecc:g:zy8AAOSwGD1b9TKZ:rk:1:pf:1&frcectupt=true (https://www.ebay.com.au/itm/GM328A-Component-Tester-Multifunctional-Meter-Graphic-Transistor-Tester-W1/352521940684?hash=item5213f1eecc:g:zy8AAOSwGD1b9TKZ:rk:1:pf:1&frcectupt=true)

My first thoughts would be a problem with the polarity or second that something is wrong with the jack. My advice would be to test the polarity of the jack against the pins of the 9V battery connector (using the continuity function on your multimeter). These should essentially be a dead short between the respective jack and 9V connector pins.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 11, 2019, 05:53:17 am
@Nation
  I've run the kit version of that one on a 9v switching, 9v linear, and battery without any issues.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jakeisprobably on February 11, 2019, 06:04:54 am
I was looking at the github schematic. the same exact firmware for 28pin is used w/o any changes in the 40pin? (or maybe the better Qn, how many versions are there in the wild? I could see special version for specific LCDs, but for 40pin?)
  Go tp software, hit the readme file. Edit the make file then check the config.h for further details. The KH version doesn't list the m644/m1284 options in the commented out stuff but they are all listed in the config.h file. The makefile options are just there to select th3 right AVRdude setup. You can select any processor AVRdude supports here. The important thing is what the header is configured for. Karl's code is a bit harder to follow if you want to play with a lot of options. Markus's version is a bit easier for me to play with.
 Either way, you just manually add the m644/m644p/m1284/m1284p into the makefile option to get it working.
Title: Re: $20 LCR ESR Transistor checker project
Post by: nation on February 11, 2019, 07:06:32 am
Sorry for the newb question.

I have had 3 of these, 2 bought a year ago and I just had another delivered today, and none of them work with an external 9v power supply. If I hook up a battery clip and connect external power via the battery clip it works. I thought this might have been an assembly or design fault that may be fixed in later runs but it's there with the new unit also.

What's possibly going on here that an external power supply plugged directly in won't work? And how do I fix it.

This is the tester I have

https://www.ebay.com.au/itm/GM328A-Component-Tester-Multifunctional-Meter-Graphic-Transistor-Tester-W1/352521940684?hash=item5213f1eecc:g:zy8AAOSwGD1b9TKZ:rk:1:pf:1&frcectupt=true (https://www.ebay.com.au/itm/GM328A-Component-Tester-Multifunctional-Meter-Graphic-Transistor-Tester-W1/352521940684?hash=item5213f1eecc:g:zy8AAOSwGD1b9TKZ:rk:1:pf:1&frcectupt=true)

My first thoughts would be a problem with the polarity or second that something is wrong with the jack. My advice would be to test the polarity of the jack against the pins of the 9V battery connector (using the continuity function on your multimeter). These should essentially be a dead short between the respective jack and 9V connector pins.

Well that was easy, thanks Pedro. The jack on my unit is wired up as center positive. I used a reverse polarity adapter between my power supply and the jack and it fired up. Didn't know many gadgets use center positive wiring.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 11, 2019, 07:43:27 am
Almost all barrel jacks are center positive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Bratster on February 11, 2019, 08:41:13 pm
Almost all barrel jacks are center positive.
Unless you're in the audio world, unfortunately a lot of their stuff is center negative which is freaking annoying.

Sent from my Fi Moto x4 using Tapatalk

Title: Re: $20 LCR ESR Transistor checker project
Post by: nation on February 11, 2019, 11:43:02 pm
Almost all barrel jacks are center positive.
Unless you're in the audio world, unfortunately a lot of their stuff is center negative which is freaking annoying.

Sent from my Fi Moto x4 using Tapatalk

Interesting, I didn't know. Never really paid attention to wall warts. I'm used to the Boss standard in the guitar world which are center negative and assumed that was standard polarity for general electronics.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CatalinaWOW on February 12, 2019, 02:44:07 pm
This is all commentary on how difficult it is to agree on and propagate standards.  In the US the best that could achieved was a law requiring wall warts to be marked with polarity, voltage and current characteristics.  The latter are often wildly off but the polarity is almost always correct.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 13, 2019, 11:00:16 pm
Get your programmers ready. ;) The new m-firmware 1.35 comes with several improvements, bug fixes and new features.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on February 13, 2019, 11:23:38 pm
I'll add the firmware here in case people don't wanna dl the entire tarball.

v1.35m 2019-02
- Added option to use probe pair specific capacitance offsets instead of
  an average offset for all probes (CAP_MULTIOFFSET).
- Corrected pin definition for ST7920 4-bit parallel mode in config_644.h
  (reported by jakeisprobably@EEVblog).
- Added support for 3-wire SPI to SSD1306 driver.
- Extended SPI driver to support sending 9 bit frames (bitbang only).
- Fixed issue with increasing deviation of resistors between 7k5 and 19k5 Ohms
  in CheckResistor() (reported by Vitaliy).
- Added alternative delay loop in IR_Send_Pulse() which is enabled by
  SW_IR_TX_ALTDELAY (thanks to Vitaliy).
- The configuration switch for additional IR protocols SW_IR_EXTRA was
  replaced by SW_IR_RX_EXTRA for the receiver/decoder and SW_IR_TX_EXTRA
  for the sender.
- Fixed issue with missing newline in Display_NextLine() for remote commands.
- Changed output for SIRC in IR_Decode() to reflect native protocol
  (suggested by Vitaliy).
- Fixed bug in IR_Send_Code() for SIRC-20 (reported by Vitaliy).
- Updated var_russian.h (thanks to indman@EEVblog).
- Added automatic power-off for auto-hold mode (POWER_OFF_TIMEOUT).
- Separated pin configuration for test push button and power control
  (CONTROL_PORT -> POWER_PORT and BUTTON_PORT).
- Several minor improvements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 14, 2019, 11:54:58 am
Hopefully the github mirror will catch up soon (https://github.com/svn2github/transistortester). I don't like the SVN either. ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on February 15, 2019, 04:13:41 pm
I flashed 1.35m but the top, bottom, left, right letters on 1602 screen are missing
Any 1602 user facing this issue?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 15, 2019, 06:10:05 pm
That's a strange issue! 1.35m works fine with my HD44780 based 16*2 text displays. Have you changed the default settings for the HD44780 driver?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 16, 2019, 03:57:10 pm
Hi,madires!
Did you see information on the new ATMega328 chip clone - LGT8F328P from LogicGreen Technologies https://www.electrodragon.com/w/images/b/b6/LGT8F88P_LGT8F168P_LGT8F328P_translated.pdf (https://www.electrodragon.com/w/images/b/b6/LGT8F88P_LGT8F168P_LGT8F328P_translated.pdf) ?
Speed up to 32 MHz, ADC -12 bit, is an opportunity diff. inclusion of inputs and gain of an input signal in 8/16/32 times and there are a lot of other interesting opportunities.
Whether its use in a tester is possible?  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 16, 2019, 08:00:32 pm
That AVR clone has some interesting additional features! What I dislike is the that the EEPROM is shared with the flash for the 32kB type. 64kB or 128kB flash would be great.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on February 17, 2019, 12:57:34 am
Thanks, indman. Interesting µC. ED sells 5 for US$3.40 (https://www.electrodragon.com/product/5pcs-logicgreen-lgt8f328p/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on February 17, 2019, 07:47:59 am
Hi,madires!
Did you see information on the new ATMega328 chip clone - LGT8F328P from LogicGreen Technologies https://www.electrodragon.com/w/images/b/b6/LGT8F88P_LGT8F168P_LGT8F328P_translated.pdf (https://www.electrodragon.com/w/images/b/b6/LGT8F88P_LGT8F168P_LGT8F328P_translated.pdf) ?
Speed up to 32 MHz, ADC -12 bit, is an opportunity diff. inclusion of inputs and gain of an input signal in 8/16/32 times and there are a lot of other interesting opportunities.
Whether its use in a tester is possible?  :D

The code in config328. Lines of other displays removed.

Code: [Select]
#define LCD_HD44780
#define LCD_TEXT                        /* character display */
#define LCD_PAR_4                       /* 4 bit parallel interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_DB_STD                      /* use standard pins 0-3 for DB4-7 */
#define LCD_DB4          PD0            /* port pin used for DB4 */
#define LCD_DB5          PD1            /* port pin used for DB5 */
#define LCD_DB6          PD2            /* port pin used for DB6 */
#define LCD_DB7          PD3            /* port pin used for DB7 */
#define LCD_RS           PD4            /* port pin used for RS */
#define LCD_EN1          PD5            /* port pin used for E */
#define LCD_CHAR_X       16             /* characters per line */
#define LCD_CHAR_Y       2              /* number of lines */
#define FONT_HD44780_INT                /* internal 5x7 font: international */
//#define FONT_HD44780_CYR                /* internal 5x7 font: Cyrillic */

I'm getting these three screens at boot

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 17, 2019, 08:53:23 am
Thanks, indman. Interesting µC. ED sells 5 for US$3.40 (https://www.electrodragon.com/product/5pcs-logicgreen-lgt8f328p/).
Is issued in the case QFP48L and QFP32L
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2019, 10:24:52 am
The code in config328. Lines of other displays removed.

I'm getting these three screens at boot

Looks like the default settings for the HD44780 display. And there's nothing wrong with the second screen. But "Vt Tester" is strange, unless you have changed the string in variables.h. Maybe a wonky signal line to the display? Connection issue?
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on February 17, 2019, 02:58:24 pm
I had to convert bitmaps/font_HD44780_cyr.h and bitmaps/font_HD44780_int.h to UTF8 to solve an error during the make all command(as stated here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2014681/#msg2014681))

Other than that I don't think I changed anything significant. I reverted back to 1.34 and it works fine as usual.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2019, 05:15:07 pm
When FONT_HD44780_CYR isn't enabled the content of bitmaps/font_HD44780_cyr.h is ignored as the precompiler commands simply hide the variables. But I found a strange character at the beginning of bitmaps/font_HD44780_cyr.h and I removed it. Interestingly my compiler didn't complain about that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 17, 2019, 05:35:03 pm
I compiled a firmware Markus of 1.35 English for HD44780 and checked its work in Proteus.
I did not receive any errors at compilation, everything works normally.
Also normally the firmware works with the Cyrillic HD44780_cyr.h font.
I put screenshots of the program. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on February 18, 2019, 04:27:14 pm
I want to apologize, the Russian font 16 font_8x16_cyrillic_vfp.h does not work, I fixed it, besides you need to add lines to the file ST7565R.c:
/ * fonts and symbols * /
/ * vertically aligned, vertical bit order flipped, bank-wise grouping * /
#include "font_8x8_vf.h"
#include "font_8x16_vfp.h"
#include "font_8x8_CYRILLIC_vf.h"
#include "font_8X16_CYRILLIC_vfp.h"
#include "symbols_24x24_vfp.h"
Checked on Hiland M644.
Dear madires, replace in your files.
Thank!
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on February 18, 2019, 06:28:32 pm
Sorry for the newb question.

I have had 3 of these, 2 bought a year ago and I just had another delivered today, and none of them work with an external 9v power supply. If I hook up a battery clip and connect external power via the battery clip it works. I thought this might have been an assembly or design fault that may be fixed in later runs but it's there with the new unit also.

What's possibly going on here that an external power supply plugged directly in won't work? And how do I fix it.

This is the tester I have

https://www.ebay.com.au/itm/GM328A-Component-Tester-Multifunctional-Meter-Graphic-Transistor-Tester-W1/352521940684?hash=item5213f1eecc:g:zy8AAOSwGD1b9TKZ:rk:1:pf:1&frcectupt=true (https://www.ebay.com.au/itm/GM328A-Component-Tester-Multifunctional-Meter-Graphic-Transistor-Tester-W1/352521940684?hash=item5213f1eecc:g:zy8AAOSwGD1b9TKZ:rk:1:pf:1&frcectupt=true)

for future reference, that board is NOT a GM328A, it's a clone of the AY-AT.
i dont know if it's the same colour display though.
you will need to know this if you want to change the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: salamangkero on February 27, 2019, 04:24:17 pm
Hello. I made an account just for this little jampacked tool. i tried 1.35m firmware and my lcd went bonkers, so i tried to fix it i removed the x offset and changed font and contrast probably disabled a couple of more things since i don't have rotary encoder. still couldn't get it quite right, it keeps probing after i turn it on. I reverted back to 1.13k version in the end. Has anyone been able to make it work for this iteration of Component Tester? Please give me pointers on how to change the config328.h and config.h to match my tester. Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 28, 2019, 10:40:44 am
Have you tried the settings for the T4 listed in the Clones file?
Title: Re: $20 LCR ESR Transistor checker project
Post by: salamangkero on March 04, 2019, 02:11:39 pm
Hello madires, i have tried the settings on the Clones file. I finally got the LCD to work and set the autohold mode to default. I can't seem to find the setting to activate the menu with long press though.

Edit:

LOL! holding the underside of the switch brings out the menu after testing. i didn't know i have a capacitive encoder if there ever is such a thing. O_o
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 04, 2019, 03:57:45 pm
Hi madires!
I want to ask about unclear to me results of measurements of resistance on m-firmware.
This effect affects not only fresh firmwares 1.35, but also older firmwares.
I measure resistor resistance 0.22 Ohms with an accuracy of 1% and sometimes I receive reliable result as on photos, and sometimes the result is underestimated up to 0.1 Ohms.
I checked AY-AT on the clone and also I observe the same effect at simulation in Proteus. I found that this error appears at measurement of resistance from 0.1 - 0.25 Ohms. How can you explain it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: JoeO on March 04, 2019, 04:21:14 pm
Hi madires!
I want to ask about unclear to me results of measurements of resistance on m-firmware.
This effect affects not only fresh firmwares 1.35, but also older firmwares.
I measure resistor resistance 0.22 Ohms with an accuracy of 1% and sometimes I receive reliable result as on photos, and sometimes the result is underestimated up to 0.1 Ohms.
I checked AY-AT on the clone and also I observe the same effect at simulation in Proteus. I found that this error appears at measurement of resistance from 0.1 - 0.25 Ohms. How can you explain it?
You are using different socket pins on the ZIF socket.

Your ZIF socket has been used a lot.  That does not help the situation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 04, 2019, 04:29:51 pm
JoeO,ZIF a socket has no relation to this effect.
I wrote that I see the same error at simulation in Proteus. In Proteus there are no ZIF of sockets. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 04, 2019, 05:20:56 pm
Hello madires, i have tried the settings on the Clones file. I finally got the LCD to work and set the autohold mode to default. I can't seem to find the setting to activate the menu with long press though.

The menu is triggered by pressing the test push button twice or turning the rotary encoder anti-clockwise. It's explained in the README file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 04, 2019, 05:35:04 pm
I want to ask about unclear to me results of measurements of resistance on m-firmware.
This effect affects not only fresh firmwares 1.35, but also older firmwares.
I measure resistor resistance 0.22 Ohms with an accuracy of 1% and sometimes I receive reliable result as on photos, and sometimes the result is underestimated up to 0.1 Ohms.
I checked AY-AT on the clone and also I observe the same effect at simulation in Proteus. I found that this error appears at measurement of resistance from 0.1 - 0.25 Ohms. How can you explain it?

When it's not a contact problem then I have no idea about the cause. I'll investigate that issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: salamangkero on March 04, 2019, 05:52:42 pm
Thanks madires. I found another problem with this clone and it seems the LED gets pulled low when pressing the test button, i checked the schematic at page 9 of Ttester_eng111k and rewired it to ground and vcc with 220 ohm resistor and the problem went away. I'm now using 1.35m without any problems. I guess it's time to put together a case for this little widget. Thanks for the help, great community here. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 07, 2019, 07:38:40 pm
I want to ask about unclear to me results of measurements of resistance on m-firmware.
This effect affects not only fresh firmwares 1.35, but also older firmwares.
I measure resistor resistance 0.22 Ohms with an accuracy of 1% and sometimes I receive reliable result as on photos, and sometimes the result is underestimated up to 0.1 Ohms.
I checked AY-AT on the clone and also I observe the same effect at simulation in Proteus. I found that this error appears at measurement of resistance from 0.1 - 0.25 Ohms. How can you explain it?

When it's not a contact problem then I have no idea about the cause. I'll investigate that issue.

I've measured a 0.22 Ohms resistor with different testers several times and wasn't able to reproduce the issue. A few times I got slightly higher values caused by contact issues which were resolved by wiggling the leads.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pleriche on March 09, 2019, 10:08:19 pm
I have the EZM version of GM328 which I've had for several years and found very useful. Recently I got it out to demonstrate to a friend and it didn't work! Any sensible person would just go and buy another, but not me. How can I not fix it? The only thing I could think of which might have caused it was that I normally keep it in a little pouch with a 9v battery, which might have touched something it shouldn't. But given that the ATMEGA328P is a DIL chip in a socket and the screen still works there's nothing I couldn't fix.
(Pic of the board and schematic as I've traced it out attached.)

The problem is that it always says Bat Empty! even though it isn't. This seems to be because something on the board is draining around 100mA from Vcc to ground, pulling the input to the 5V regulator U2 down to 5.6V and the regulator output (Vcc) to 4.4V.

I've tested all 3 transistors and tested the voltage regulator by substitution. The resistor values of the voltage divider feeding PV5 (battery monitor ADC input) are good, as are the resistors on  the base of Q2 and the collector or Q3. I can see no solder bridges or dry joints and I've resoldered all the IC socket pins and a fair few others.

But if I pull the ATMEGA chip the current drain drops to a reasonable value for the LED and display backlight. If I burn my spare chip with the Arduino Blink program (driving the LED through PD6) it blinks nicely but I haven't succeeded in getting any of the Arduino ST7565 examples to run.

Early on I decided to suck the firmware out of the chip and burn another, but it seems to be read-protected. So I found the source online, built it for the ST7565 display and uploaded it to another chip. On about the 3rd attempt I got the display orientation correct but the heavy current drain is still there! I could easily believe on of the GPIO pins was shorting to ground but not that a fresh chip had the same fault!

Just for the moment I'm stuck. I was hoping that describing the problem and my steps so far would unblock my brain but as yet it hasn't. Can anyone help?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 10, 2019, 12:55:11 am
Did you try disconnecting the display?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Willem52 on March 10, 2019, 08:19:16 am
Please, I would check the electrolytic capacitors...
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 10, 2019, 08:46:17 am
I have the EZM version of GM328 which I've had for several years and found very useful.
 Can anyone help?
Attention! Only for owners of a clone of EZM GM328!
For a firmware of author's revision the 500-th is higher to you it is necessary to disconnect PD5 port (11pin) ATMega328 from a payment of the display or to use the LCD_SPI_OPEN_COL parameter at compilation. Otherwise you risk to damage the processor as at this port at new revision of a firmware there is a high level (5B) and through a display payment he unites on the ground  that leads to consumption of current up to 100 mA and to heating of the processor. Thanks Karl-Heinz of Kübbeler which helped to solve this problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pleriche on March 10, 2019, 09:23:49 am
Quote
Please, I would check the electrolytic capacitors...

Thank you Willem52 but that was one of the first things I tried. But if that were the problem it's hard to see how the consumption would drop by around 100mA when I pulled the chip.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pleriche on March 10, 2019, 09:50:42 am
Quote
...it is necessary to disconnect PD5 port (the 11pin) ATMega328...

Many thanks @indman - that schematic seems to be that of my device. I bent PD5 (pin 11) so as not to enter the IC socket and the current consumption is normal! It now seems to want to enter a test and calibration mode (It says "Short Probes") so I'll have to sort that out later. I've now cut the track between pin 11 and LCD pin 6. Strange that it worked for a couple of years (occasional use) and only recently failed. The only rational explanation I can think of is that in an act of infinite kindness, my fairy godmother crept into my den while I was asleep and updated the firmware for me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cairong1983 on March 10, 2019, 08:11:30 pm
Hello Everyone, I am new here.

A year ago I bought a Transistor Tester on Aliexpress, Only I had forgotten to look in which language it was, now it turns out that he is in Russian, I have been looking a lot on the internet to see if I can program the Atmega328p Chip on a new one with the English version, As I have read this is possible, I have seen here and there in this forum section references where I can download the relevant files, And also miscellaneous programs downloaded to To upload a new version, but it does not work very well, and since this topic is very big, I do not know where I can find the right way to do this.
Have also looked on youtube how I could do it, but I really do not see how it should be.
Who has and can explain to me clearly how to do it.
An Ardiuno I made the Programmer with Arduino as ISP, the two Atmega328p Chip I have uploaded a bootloader, and then I lose what I have to do and what to use in terms of software. I have downloaded avrdude, Xloader, Win AVR.

Who can help me further?

Richard D
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 10, 2019, 08:52:22 pm
@Cairong
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg810893/#msg810893
Title: Re: $20 LCR ESR Transistor checker project
Post by: pleriche on March 10, 2019, 09:38:46 pm
I have the EZM version of GM328 which I've had for several years and found very useful.
 Can anyone help?
Attention! Only for owners of a clone of EZM GM328!
... use the LCD_SPI_OPEN_COL parameter at compilation...

Err, not out of the woods yet. Where is the LCD_SPI_OPEN_COL parameter? I've grepped through all the source (v1.35m) and couldn't see it or anything resembling it.

As I said, I bent pin 11 to disconnect PD5 and it reported a reasonable value for battery voltage, and went into some kind of setup or calibration. I had to leave it for a few hours, but coming back I cut the track between PD5 and LCD pin 6 and bent the ATMega328 pin 11 back, and once again I got the battery empty message! I checked there was no continuity between PD6 and LCD pin 6 but nevertheless bent pin 11 out again. I also noticed PD4 is not used so bent that out in case that was having a similar issue, but no improvement.

Perhaps the chip was damaged. So I programmed my spare chip with a blink program to verify that PD4 - PD7 all worked as outputs, then programmed it with v1.35m (ST7565R bit-bang SPI) which now displays nothing on the screen. Consumption is 24mA. That seemed to work before, albeit with a high current drain through PD5. Maybe I need this LCD_SPI_OPEN_COL - I have to confess I didn't fully understand what you were saying about that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 11, 2019, 09:56:52 am
LCD_SPI_OPEN_COL is a feature of the k-firmware. Anyhow, it shouldn't be hard to modify the display driver of the m-firmware to do the same.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pleriche on March 12, 2019, 05:42:29 pm
Double-checked Makefile, config.h and config_328.h (don't think I changed anything though) and rebuilt. Since last time I added a 22uF capacitor to the reset pin of the Arduino as ISP (not the target chip) and did make upload.

Previously I couldn't get avr-dude to work on my linux box and had to copy the hex file to Windoze and burn it from there. Probably I only burnt the flash and not the eeprom.

Current consumption is now reasonable, varying between 15 - 20mA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ngoctuct on March 14, 2019, 01:16:26 pm
hi, sorry my english,
Can you send me that firmware?
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 14, 2019, 01:58:48 pm
You can download a precompiled k-firmware for several tester models at https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/. (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/.) And the m-firmware has to be compiled by you (see the Clones file for settings for some models).
Title: Re: $20 LCR ESR Transistor checker project
Post by: ngoctuct on March 14, 2019, 02:32:17 pm

You can download a precompiled k-firmware for several tester models at https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/. (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/.) And the m-firmware has to be compiled by you (see the Clones file for settings for some models).

i try some firmware but it not work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pleriche on March 14, 2019, 03:37:47 pm
It looks like yours is GM328A whereas mine is GM328, so my firmware won't work for you. And I don't see a precompiled GM328A on the site quoted by Madires.

Take a look at https://www.elektroda.pl/rtvforum/topic3402823.html (https://www.elektroda.pl/rtvforum/topic3402823.html) - it looks like they may have your firmware at the bottom of the page just before the comments though you may have to work hard with Google Translate (as I did) to understand the Polish and hence register.

Alternatively, compiling from source is quite easy under Linux - the hardest part might be determining which display you have. You just have to edit the Makerfile, config_328.h and config.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 14, 2019, 05:35:39 pm
i try some firmware but it not work.

Your tester model seems to be an AY-AT, i.e. mega328_color_kit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ngoctuct on March 14, 2019, 11:05:45 pm
i try some firmware but it not work.

Your tester model seems to be an AY-AT, i.e. mega328_color_kit.
thanks.
there is a problem with the button. when I pressed the push button, the menu was displayed but the functions could not be selected

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Title: Re: $20 LCR ESR Transistor checker project
Post by: ngoctuct on March 15, 2019, 01:49:20 am
i try mega328-color-kit. but not work(https://uploads.tapatalk-cdn.com/20190315/9da0573ef1d32f0118a2994ac116d101.jpg)

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Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 15, 2019, 12:15:14 pm
Have you programmed the flash and the eeprom?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rooster Cogburn on March 18, 2019, 10:03:36 am
Hi all, stupid question incoming.

I bought a version of the tester a couple of years ago:

(https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSiir-OyjU3_obyJ8zgsPPUluPPyudGdPM-dUZsX3Cclbzj4A5j)

Really like the thing. I bought this one specifically because I thought it had the nicest looking UI. Very 'graphical', uses the full display instead of a bunch of text squished into the upper-left corner. I've seen there are more capable versions of this device with a signal generator, frequency counter, volt meter, IR decoder and perhaps other stuff (anything neat that's non-obvious?). Would this be a good upgraded version to buy:

https://www.aliexpress.com/item/LCD-GM328A-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator-SMT/32812240696.html (https://www.aliexpress.com/item/LCD-GM328A-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator-SMT/32812240696.html)

(https://ae01.alicdn.com/kf/HTB18Kg8djqhSKJjSspnq6A79XXaO/LCD-GM328A-Transistor-Tester-Diode-Capacitance-ESR-Voltage-Frequency-Meter-PWM-Square-Wave-Signal-Generator-SMT.jpg_640x640.jpg)

? Would I need to update the firmware on it? Would I miss much if I didn't?

Also, is this still the best user manual to introduce me to the new features:

https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=236653

?

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 18, 2019, 03:08:41 pm
Yep. the AY-AT is a nice clone. You don't have to upgrade the firmware if you're happy with the features, but the open source firmwares (k and m) offer a lot more. The fancy graphics of the modified firmware consume a lot of the flash memory. The firmware of the AY-AT supports just two IR protocols, IIRC. The m-firmware offers about 15 (and four different modulation types).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rooster Cogburn on March 18, 2019, 04:01:30 pm
Didn't even think about the graphics consuming flash, but of course, that makes a lot of sense. So is the AY-AT the unquestionably best ready to order cheap clone or do the other variants at least offer some sort of trade-off that might be better for some? It's really hard to an outsider to understand the differences between all the devices and firmware branches, is there a manual or even some kind of comparison to see what I'd be missing?
Title: Re: $20 LCR ESR Transistor checker project
Post by: KD0CAC John on March 18, 2019, 04:46:17 pm
Hay guys ,
I have a couple of these clone / what ever .
I like having more than one , like one at the bench , another in the travel box - around $20+- the prices makes it easy .
I do like the graphics - more internal info on device being tested , also the graphics may miss-label a defective component , so another indicator of failure .
I hand not thought about the " taking up memory " , just wondering how much performance / capabilities having the graphics takes away ?
Thanks again
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 18, 2019, 05:43:18 pm
Didn't even think about the graphics consuming flash, but of course, that makes a lot of sense. So is the AY-AT the unquestionably best ready to order cheap clone or do the other variants at least offer some sort of trade-off that might be better for some? It's really hard to an outsider to understand the differences between all the devices and firmware branches, is there a manual or even some kind of comparison to see what I'd be missing?

There's no perfect clone. If you want all the hardware options you have to build a tester yourself. You'll find the documentation for the k-firmware at https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/) (download the archive and extract ttester.pdf). And the m-firmware includes a README file with all details.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rooster Cogburn on March 18, 2019, 06:12:30 pm
I often find that long-running projects are quite impenetrable for outsiders who have not been following along from the beginning. For instance, try to learn about the xbox/playstation modding scene. It's all obvious if you've been into this stuff for 10 years, but if you just try to get a handle on things all you'll get is stuff like "It's easy, you'll have to unprotect your Virtual EEPROM with the Enigmah Engineering disc ftp'ed to your F-partition right after TSOP modding your 1.4 board with the nulled out UnleashX NDure mod patcher through Chimp while hot-swapping your IDE cable. The procedure is describe at <link to deleted forum post>".

I generally try to RTFM and google before I ask a question as writing it and then having other people read and respond to it is a waste of time for everybody. But here with this transistor tester after >1h of Googling I'm not really getting anywhere. It's such a rats nest of forum threads, AliExpress products, random stuff on GitHub, various PDF files, READMEs, SVN repos etc. I have no idea what's outdated or who's who and what any of this actually means.

Like, I've heard of this mysterious "m-firmware" and a google search gets me to this:

https://github.com/svn2github/transistortester/tree/master/Software/Markus (https://github.com/svn2github/transistortester/tree/master/Software/Markus)

Apparently the README should explain things. It does, if you already know the history of the project and who Karl-Heinz is and what he's been up to. Seems like he wrote this:

https://www.mikrocontroller.net/attachment/143813/TTester_096k.pdf (https://www.mikrocontroller.net/attachment/143813/TTester_096k.pdf)

which is neat and detailed, but it has 2012 in the title, so no idea if that still has any relevance to the current state of the code and whatever I can buy on AliExpress today.

There's some info on https://www.mikrocontroller.net (https://www.mikrocontroller.net), but even that doesn't really help in telling the different hardware platforms apart, getting some kind of idea what the differences between the software releases are and what to actually buy.

Unless I'm being extremely dense here, the only way to know what the differences between the hardware and software releases are is either

- Spend days re-tracing the entire history of this project and read hundreds of pages of forum threads
- Ask the obvious questions (probably happens once a week) and hope somebody has pity on you

I think it would be super awesome if somebody in the know could just spend 5min writing a basic 'Buyers FAQ' with a last-updated date on it that just tells people what to buy. If there's more than a single obvious choice then maybe a paragraph of text and a little table on what the meaningful differences and trade-offs are between the different hardware / software releases so the buyer can make an informed choice. That probably be enough for 99% of the people looking to buy this thing and hopefully cut down the amount of repetitive stupid questions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 18, 2019, 06:13:03 pm
I hand not thought about the " taking up memory " , just wondering how much performance / capabilities having the graphics takes away ?

It depends on the size of the bitmaps and the functions to display them, also functions for drawing lines and so on. Basic graphics support including a font could be around 6 or 8 kB. Any additional stuff will eat more. BTW, k and m-firmware can display symbols with pinout too. And if you like to go really fancy the m-firmware supports a touchscreen interface (ATmega 644 or 1284 recommended).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 18, 2019, 06:30:24 pm
Like, I've heard of this mysterious "m-firmware" and a google search gets me to this:

https://github.com/svn2github/transistortester/tree/master/Software/Markus (https://github.com/svn2github/transistortester/tree/master/Software/Markus)

The svn2github service was shut down a few months ago, so the mirror at github is outdated. The SVN I've mentioned earlier is the official repo and it has all the stuff, also the current documentation.

I think it would be super awesome if somebody in the know could just spend 5min writing a basic 'Buyers FAQ' with a last-updated date on it that just tells people what to buy. If there's more than a single obvious choice then maybe a paragraph of text and a little table on what the meaningful differences and trade-offs are between the different hardware / software releases so the buyer can make an informed choice. That probably be enough for 99% of the people looking to buy this thing and hopefully cut down the amount of repetitive stupid questions.

That would be great! I'm busy with the m-firmware. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: grantb5 on March 18, 2019, 06:46:06 pm
I think it would be super awesome if somebody in the know could just spend 5min writing a basic 'Buyers FAQ' with a last-updated date on it that just tells people what to buy. If there's more than a single obvious choice then maybe a paragraph of text and a little table on what the meaningful differences and trade-offs are between the different hardware / software releases so the buyer can make an informed choice. That probably be enough for 99% of the people looking to buy this thing and hopefully cut down the amount of repetitive stupid questions.

Yeah I'm in the same boat. I bought a TC-1 in a plastic case off eBay and googling brought me here.  I can tell it's a slightly different beast and was thinking of getting my feet wet on the state-of-the-art for this project as it is today. Totally lost ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rooster Cogburn on March 18, 2019, 07:03:20 pm
That would be great! I'm busy with the m-firmware. ;)

(please don't take this personal)

This general attitude is absolutely the norm among software & EE. Most people refuse to even spend 1min on documentation for every 100min hacking. GitHub is littered with projects that smart people spend combined lifetimes on that'll never be seen or be of use to anybody because they could not be bothered to spend 5min on adding a screenshot and a paragraph of text on 'how to build & install'. How may times have you seen some README on GitHub where you literally can't even figure out what this is supposed to do because just writing ONE SENTENCE on what this is was asking for to much.

If you Google for 'transistor tester m-firmware' I don't find your canonical repository. And how would I even know to search for that if I didn't dig through a giant forum thread telling me that's the current branch of code for this project (I guess it is?). Looking at the janky SVN browser (for most people it's anyway 'if its not on GitHub it might as well not exist') and trying to click on the PDF docs all I get is 'Display of files larger than 512 KB disallowed by configuration'. I guess I need to install SVN.

I just see this kind of stuff over, and over again. It's the engineer's disease. Brilliant people dedicate thousands of hours of their time to build truly impressive and useful things, only to stop two steps in front of the finishing line. All it would take is brief, simple page on GitHub or a community wiki with a few words on what is the state of this project, where to get the current docs/code/schematics, a paragraph or two for the 'Buyers FAQ', done. It's like you spend a year of your life building me this beautyful car, but when I ask you for the keys all I get is a shrug and 'read through this forum thread, somewhere in there is a link to a gopher server containing a Rot13 encoded text file with the coordinates of where I buried it in your backyard. Good luck, I need to build another car'.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 18, 2019, 07:32:15 pm
Have you seen the project's page at https://www.mikrocontroller.net/articles/AVR_Transistortester (https://www.mikrocontroller.net/articles/AVR_Transistortester)? And Karl-Heinz' documentation with over 130 pages? The m-firmware's README with about 1800 lines? We can't please everyone, but there's no lack of documentation. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 18, 2019, 07:35:06 pm
the only way to know what the differences between the hardware and software releases are is either...

The best way is to just dive in. The beauty of this tester is that the cost of entry is so low. You could even breadboard it yourself. Easy to modify and upgrade too. It's not a life changing decision.


How may times have you seen some README on GitHub where you literally can't even figure out what this is supposed to do

It's usually because they wrote the code for themselves, and you should be thankful that they decided to share it.



Title: Re: $20 LCR ESR Transistor checker project
Post by: Rooster Cogburn on March 18, 2019, 08:30:08 pm
Have you seen the project's page at https://www.mikrocontroller.net/articles/AVR_Transistortester (https://www.mikrocontroller.net/articles/AVR_Transistortester)? And Karl-Heinz' documentation with over 130 pages? The m-firmware's README with about 1800 lines? We can't please everyone, but there's no lack of documentation. ;D

Yep, I've seen those and have even explicitly mentioned all three as things I checked out. That wasn't really what I was looking for and still left me rather confused, probably the same for the other two people that immediately chimed in asking for advice as well. Way too in-depth, confusing and mostly helpful if you're already hacking on the project and have the general idea down. Maybe I'm being a bit stupid here, but it's always a good assumption to make about your users :D I can guarantee you that if I actually took the time to digest all of this I could write a few paragraphs of text that would answer 90% of the questions of 90% of the people approaching this for the first time and being lost. And so could you. From experience, this kind of feedback is about as likely to be accepted as explaining to a Linux proponent why Linux on the desktop is unlikely to take off ("I don't understand, it's really easy and works well for me, all you have to do is...").


How may times have you seen some README on GitHub where you literally can't even figure out what this is supposed to do

It's usually because they wrote the code for themselves, and you should be thankful that they decided to share it.

You don't understand where I'm coming from. I'm not saying this because I think I'm entitled to receiving documentation and a nice website from the author. They don't owe me anything. I don't get it from their point of view. Writing an introduction text, tutorial, making a friendly landing page and taking a few pictures should feel like a victory lap, not a chore. You get to show of your amazing creation to the world and get the pleasure of people actually using it. Plus it's like 15min of work and most likely the most effective 15min of the entire project in terms of real world results for your time. I'm not thankful for code thrown over the fence, it has no value to me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 18, 2019, 08:35:43 pm
Yes but that takes time away from actual development.

They are not interested in your thanks either.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rooster Cogburn on March 18, 2019, 10:18:07 pm
Yes but that takes time away from actual development.

Yes, it does.

They are not interested in your thanks either.

But you said I should be thankful? :-\
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 18, 2019, 10:23:25 pm
ok, happy, if you like.
And if it doesn't make you happy, then you can get a refund.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on March 18, 2019, 11:59:38 pm
I often find that long-running projects are quite impenetrable for outsiders who have not been following along from the beginning...
after >1h of Googling I'm not really getting anywhere...

Apparently the README should explain things. It does, if you already know the history of the project and who Karl-Heinz is and what he's been up to...

...it has 2012 in the title, so no idea if that still has any relevance to the current state of the code and whatever I can buy on AliExpress today.

There's some info on https://www.mikrocontroller.net (https://www.mikrocontroller.net), but even that doesn't really help in telling the different hardware platforms apart, getting some kind of idea what the differences between the software releases are and what to actually buy...

I think it would be super awesome if somebody in the know could just spend 5min writing a basic 'Buyers FAQ' with a last-updated date on it that just tells people what to buy...

This would be what you're looking for:
https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 19, 2019, 01:38:58 am
You don't understand where I'm coming from. I'm not saying this because I think I'm entitled to receiving documentation and a nice website from the author. They don't owe me anything. I don't get it from their point of view. Writing an introduction text, tutorial, making a friendly landing page and taking a few pictures should feel like a victory lap, not a chore. You get to show of your amazing creation to the world and get the pleasure of people actually using it. Plus it's like 15min of work and most likely the most effective 15min of the entire project in terms of real world results for your time. I'm not thankful for code thrown over the fence, it has no value to me.

I get where you're coming from and you're right that it would be beneficial to have user-friendly documentation and a buyer's guide that covered the many testers available (or maybe just the most popular ones).

However, writing good end-user documentation, just like writing good technical documentation or good code, isn't easy and takes more than a couple of pics and 15 minutes of work. These tasks require different skillsets and few people are good at them all.

Are you good at seeing technology from a user's perspective, anticipating how best to answer their questions before they ask them? Do you have the skill to reinterpret dense technical information into an easily digestible form? If so, then this project (and many upcoming users) can benefit from a quality user-friendly manual that you could make.
Title: Re: $20 LCR ESR Transistor checker project
Post by: texaspyro on March 19, 2019, 01:43:56 am
Another problem with testers is that they are like snowflakes... no two seem to be alike.  With clones and clones of clones everywhere (even though they look / are labeled identical), what you received yesterday may have no relation to what came in today... different pin assignments and displays are a particular problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on March 19, 2019, 01:45:43 am
Yeah, that's a whole other problem. Buying from China, you never know what you're going to get (and they often steal the firmware, mod it, and don't let you see what changed, let alone document it).
Title: VN Re: $20 LCR ESR Transistor checker project
Post by: madires on March 21, 2019, 11:59:29 am
The svn2github service was shut down a few months ago. So the repo mirror at GitHub is obsolete now and therefor we've decided to set up a "warehouse" at GitHub with the most interesting files, like firmware packages, PCB files and docs for example. This provides a convenient way for you to download the latest firmware since the SVN repo is considered cumbersome by most users. You'll find the warehouse at https://github.com/madires/Transistortester-Warehouse.

And some news about the m-firmware. The next version will support STE2007/HX1230 based displays (aka Nokia 1202 display). Possibly I'll also add a driver for the PCF8814 (aka Nokia 1100 display) which is quite similar to the STE2007.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 25, 2019, 05:20:24 pm
Hi, men! :)
I want to offer you the comparative table created by me on the most popular clones.
Look attentively whether I made a mistake or passed some moments?
Sorry, if my English translation is not absolutely good
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 25, 2019, 06:50:36 pm
The LCR-TC1 requires a different firmware for the control MCU (U4) or to replace U4 by a simple circuit (TC1-Mod) to become compatible with k and m-firmware. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 25, 2019, 07:19:25 pm
The LCR-TC1 requires a different firmware for the control MCU (U4) or to replace U4 by a simple circuit (TC1-Mod) to become compatible with k and m-firmware.
These are already technical details. Nothing prevents to update the main firmware of ATmega324(644)  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on March 29, 2019, 10:18:58 am
I have the same problem with my GM328. What steps did you follow to resolve the problem ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 29, 2019, 01:05:59 pm
The 5kg hammer from the garden shed will fix that. >:D Have you tried to reprogram the ATmega? Or what did go wrong?
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on March 31, 2019, 05:17:49 pm
The 5kg hammer from the garden shed will fix that. >:D Have you tried to reprogram the ATmega? Or what did go wrong?

Yes, I tried the mega328_GM328 version I used from https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)

I always get a white blank screen.  The fuses I used are: lfuse=0xF7 hfuse=0xD9 efuse=0xFF

I even tried the versions below without success.

GM328_EZM_v1.12k_r464_EN.zip
GM328_EZM_v1.12k_r508_EN.zip
GM328_EZM_v1.12k_r541.zip

 
I suspect that the firmware does not support this display (I don't know what kind of display it has), but I am not sure.

The seller description reports that "The display unit using a 160x128 pixel color display, full-screen characters 8x20". The GM328 was working when I received it, but it had a calibration problem so I decided to reprogram the MCU. Also I can for sure that it wasn't color.

https://www.youtube.com/watch?v=JCP7oWG3D3w&t=85s (https://www.youtube.com/watch?v=JCP7oWG3D3w&t=85s)

Any recommendations?


Regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on March 31, 2019, 05:48:20 pm
did you try changing the contrast setting?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 31, 2019, 06:18:10 pm
Yes, I tried the mega328_GM328 version I used from https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)

It's an AY-AT clone. Please try mega328_color_kit. And don't forget to reprogram the EEPROM also.

The seller description reports that "The display unit using a 160x128 pixel color display, full-screen characters 8x20". The GM328 was working when I received it, but it had a calibration problem so I decided to reprogram the MCU. Also I can for sure that it wasn't color.

The AY-AT clones come with an ST7735 based color display usually. If your clone has a monochrome display you could try ST7565 for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on March 31, 2019, 07:30:29 pm
Yes, I tried the mega328_GM328 version I used from https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)

It's an AY-AT clone. Please try mega328_color_kit. And don't forget to reprogram the EEPROM also.

The seller description reports that "The display unit using a 160x128 pixel color display, full-screen characters 8x20". The GM328 was working when I received it, but it had a calibration problem so I decided to reprogram the MCU. Also I can for sure that it wasn't color.

The AY-AT clones come with an ST7735 based color display usually. If your clone has a monochrome display you could try ST7565 for example.

When you say don't forget to reprogram the EEPROM what do you mean? When I re-program the MCU with the hex file that's exactly what I am not doing?

The display does not have any PCB connection marks. It just says J1 with 8 pins. I tried to connect the display with my breadboard according to the following table

https://cdn.instructables.com/FD6/5BW7/IJ3763UJ/FD65BW7IJ3763UJ.LARGE.jpg?auto=webp&width=580 (https://cdn.instructables.com/FD6/5BW7/IJ3763UJ/FD65BW7IJ3763UJ.LARGE.jpg?auto=webp&width=580)

and linking with the Adafruit_ST7735.h and Adafruit_GFX.h libraries.

The final project looks like

https://cdn.instructables.com/FEF/2S4D/IIYWSHR9/FEF2S4DIIYWSHR9.LARGE.jpg (https://cdn.instructables.com/FEF/2S4D/IIYWSHR9/FEF2S4DIIYWSHR9.LARGE.jpg)

It lights up but I get the same result, blank screen.

Regards,
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 31, 2019, 07:46:29 pm
When you reprogram the flash (hex file) you also have to reprogram the EEPROM (eep file). The EEPROM contains most text strings and other important data.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on March 31, 2019, 08:01:35 pm
When you reprogram the flash (hex file) you also have to reprogram the EEPROM (eep file). The EEPROM contains most text strings and other important data.

Shit no I didn't this !!! I will try it, but I am curious why it did not work in my breadboard!


Anyway, the display has the following ICs. A) TI Hex Inverting Buffer and Converter (7CA676M) CD4050BM G4 and B) AMS1117 DROPOUT VOLTAGE REGULATOR and an SMD resistor. Nothing else.

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on March 31, 2019, 08:28:19 pm
Yes, I tried the mega328_GM328 version I used from https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/)

It's an AY-AT clone. Please try mega328_color_kit. And don't forget to reprogram the EEPROM also.

The seller description reports that "The display unit using a 160x128 pixel color display, full-screen characters 8x20". The GM328 was working when I received it, but it had a calibration problem so I decided to reprogram the MCU. Also I can for sure that it wasn't color.

The AY-AT clones come with an ST7735 based color display usually. If your clone has a monochrome display you could try ST7565 for example.

When you say don't forget to reprogram the EEPROM what do you mean? When I re-program the MCU with the hex file that's exactly what I am not doing?

The display does not have any PCB connection marks. It just says J1 with 8 pins. I tried to connect the display with my breadboard according to the following table

https://cdn.instructables.com/FD6/5BW7/IJ3763UJ/FD65BW7IJ3763UJ.LARGE.jpg?auto=webp&width=580 (https://cdn.instructables.com/FD6/5BW7/IJ3763UJ/FD65BW7IJ3763UJ.LARGE.jpg?auto=webp&width=580)

and linking with the Adafruit_ST7735.h and Adafruit_GFX.h libraries.

The final project looks like

https://cdn.instructables.com/FEF/2S4D/IIYWSHR9/FEF2S4DIIYWSHR9.LARGE.jpg (https://cdn.instructables.com/FEF/2S4D/IIYWSHR9/FEF2S4DIIYWSHR9.LARGE.jpg)

It lights up but I get the same result, blank screen.

Regards,

The mega328_color_kit firmware worked !!! Thank you madires you are the best !

Is this display ST7735 compatible? This pinout 1-8 is the same as the
following table (TFT display pin)?

(https://cdn.instructables.com/FD6/5BW7/IJ3763UJ/FD65BW7IJ3763UJ.LARGE.jpg?auto=webp&width=580)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 01, 2019, 09:56:09 am
Most SPI driven displays got the same signal lines plus power and backlight. So you can't deduce the controller from the pinout.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on April 01, 2019, 06:47:02 pm
Most SPI driven displays got the same signal lines plus power and backlight. So you can't deduce the controller from the pinout.

I am not able to use the display with Adafruit_ST7735 and Adafruit_GFX libraries in my breadboard (standalone Arduino project). Can someone write down the ST7735 controller Pinout following the attached schematic?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 02, 2019, 11:37:47 am
Simply take the settings for the AY-AT clone:
Code: [Select]
PD0 - /RESET
PD1 - D/C
PD2 - SCL
PD3 - SDA
PD5 - /CS

and correlate them with your display:
Code: [Select]
1 - anode of backlight LED
2 - /RESET
3 - D/C
4 - SDA
5 - SCL
6 - /CS
7 - Vcc
8 - Gnd
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on April 02, 2019, 04:46:56 pm
Simply take the settings for the AY-AT clone:
Code: [Select]
PD0 - /RESET
PD1 - D/C
PD2 - SCL
PD3 - SDA
PD5 - /CS

and correlate them with your display:
Code: [Select]
1 - anode of backlight LED
2 - /RESET
3 - D/C
4 - SDA
5 - SCL
6 - /CS
7 - Vcc
8 - Gnd

Yeap !! It worked !! I finally saw some text in the display. Thanks once again! I attach the pinout table with photos for everyone may need it.

PS: Pin2= /RESET you mean NOT(RESET) enabled and Pin6 = /CS you mean Not(CS) enabled ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 02, 2019, 06:16:08 pm
The leading "/" indicates that the signal is low active (reversed logic).
Title: Re: $20 LCR ESR Transistor checker project
Post by: fastguido on April 04, 2019, 08:31:03 pm
I hope someone can help this analog design guy from the past. I have had a Banggood 328 tester for about a couple of years now, been working fine and use it daily. Last week the display wouldn't show any characters, power LED would come on, if I inserted a LED in the test zip it would flash a few times, checked the power supply, ok.  2.5V reference, ok.  So I borrowed a friends same tester and swapped the 328 from his to mine, (thank God for sockets) and it works, so my 328 is bad. I just ordered a couple of new 328's (one for a spare) to replace mine in case it's not just a software problem. This is where I am at this point, I have no knowledge on programming accept some very basic Arduino stuff, I have only a MAC, all the threads on programing the 328 that I have read on this thread are way over my head, it's all Greek to me. Is there someone on here that could program a couple of 328 for me or another idea. Thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on April 04, 2019, 10:22:12 pm
If programming is over your head then just buy another one
Here's one for $6
ebay.com/itm/112224259968
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on April 05, 2019, 12:23:26 am
If programming is over your head then just buy another one
Here's one for $6
ebay.com/itm/112224259968
Why is it most of these idiot mfg's can never figure out how to weave traces under a simple 14-pin ZIF-socket? This model sure is cheap, and there's only one valid 123 position (upper left row) out of a minimum of 4 easy ZIF configurations.

I'd like to suggest that mikrocontroller.net would add info on optimal PCB routing for ZIF sockets. Anyone agree? :-//
 
(https://i.ebayimg.com/images/g/alIAAOSwZQRYZNmF/s-l1600.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: fastguido on April 05, 2019, 12:57:24 am
If programming is over your head then just buy another one
Here's one for $6
ebay.com/itm/112224259968
Thats against my old school ways to replace, just throw away not my style.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on April 05, 2019, 02:09:35 am
I'd like to suggest that mikrocontroller.net would add info on optimal PCB routing for ZIF sockets. Anyone agree?  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on April 05, 2019, 06:07:05 am
You don't have to throw anything away (except the dead chip). Everything else can be reused.

I don't think anybody will program your chips for you or tutor you on embedded development so I don't see what other choice you have.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on April 05, 2019, 08:42:12 am
I hope someone can help this analog design guy from the past. I have had a Banggood 328 tester for about a couple of years now, been working fine and use it daily. Last week the display wouldn't show any characters, power LED would come on, if I inserted a LED in the test zip it would flash a few times, checked the power supply, ok.  2.5V reference, ok.  So I borrowed a friends same tester and swapped the 328 from his to mine, (thank God for sockets) and it works, so my 328 is bad. I just ordered a couple of new 328's (one for a spare) to replace mine in case it's not just a software problem. This is where I am at this point, I have no knowledge on programming accept some very basic Arduino stuff, I have only a MAC, all the threads on programing the 328 that I have read on this thread are way over my head, it's all Greek to me. Is there someone on here that could program a couple of 328 for me or another idea. Thanks in advance.

You tested the ATMega328p chip and you found it bad? In that case, yes you can order new ATMega328p new chips and program them. Its not so hard! You need
an USPAsp programmer + AVR Board

https://www.ebay.com/itm/Programmer-AVR-Minimum-System-Board-ATMEGA16-ATmega32-USB-ISP-USBasp-For-ATMEL/351110426836?epid=2114364063&hash=item51bfcff0d4:g:fNgAAOxydlFSviwG&frcectupt=true (https://www.ebay.com/itm/Programmer-AVR-Minimum-System-Board-ATMEGA16-ATmega32-USB-ISP-USBasp-For-ATMEL/351110426836?epid=2114364063&hash=item51bfcff0d4:g:fNgAAOxydlFSviwG&frcectupt=true)

Install AVRdude http://savannah.nongnu.org/projects/avrdude (http://savannah.nongnu.org/projects/avrdude) and download the mega328_color_kit version below

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/)

Then just use the command below to program flash and eeprom

avrdude -c usbasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c usbasp -p m328p -U eeprom:w:TransistorTester.eep

Finally program also the efuses with the follow command and you are ready !

avrdude -p m328p -F -P usb -c usbasp - -U lfuse:w:0xFF:m -U hfuse:w:0xD9:m -U efuse:w:0xF4:m -U lock:w:0x0F:m
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 05, 2019, 09:32:02 am
I'd like to suggest that mikrocontroller.net would add info on optimal PCB routing for ZIF sockets. Anyone agree?  :-//

I'm not sure if that would help. We have some hints for clone vendors already (even in Mandarin) and haven't received any feedback from Chinese vendors so far.
Title: Re: $20 LCR ESR Transistor checker project
Post by: fastguido on April 05, 2019, 03:31:14 pm
I hope someone can help this analog design guy from the past. I have had a Banggood 328 tester for about a couple of years now, been working fine and use it daily. Last week the display wouldn't show any characters, power LED would come on, if I inserted a LED in the test zip it would flash a few times, checked the power supply, ok.  2.5V reference, ok.  So I borrowed a friends same tester and swapped the 328 from his to mine, (thank God for sockets) and it works, so my 328 is bad. I just ordered a couple of new 328's (one for a spare) to replace mine in case it's not just a software problem. This is where I am at this point, I have no knowledge on programming accept some very basic Arduino stuff, I have only a MAC, all the threads on programing the 328 that I have read on this thread are way over my head, it's all Greek to me. Is there someone on here that could program a couple of 328 for me or another idea. Thanks in advance.

You tested the ATMega328p chip and you found it bad? In that case, yes you can order new ATMega328p new chips and program them. Its not so hard! You need
an USPAsp programmer + AVR Board

https://www.ebay.com/itm/Programmer-AVR-Minimum-System-Board-ATMEGA16-ATmega32-USB-ISP-USBasp-For-ATMEL/351110426836?epid=2114364063&hash=item51bfcff0d4:g:fNgAAOxydlFSviwG&frcectupt=true (https://www.ebay.com/itm/Programmer-AVR-Minimum-System-Board-ATMEGA16-ATmega32-USB-ISP-USBasp-For-ATMEL/351110426836?epid=2114364063&hash=item51bfcff0d4:g:fNgAAOxydlFSviwG&frcectupt=true)

Install AVRdude http://savannah.nongnu.org/projects/avrdude (http://savannah.nongnu.org/projects/avrdude) and download the mega328_color_kit version below

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/)

Then just use the command below to program flash and eeprom

avrdude -c usbasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c usbasp -p m328p -U eeprom:w:TransistorTester.eep

Finally program also the efuses with the follow command and you are ready !

avrdude -p m328p -F -P usb -c usbasp - -U lfuse:w:0xFF:m -U hfuse:w:0xD9:m -U efuse:w:0xF4:m -U lock:w:0x0F:m
Thanks for the input, yes the 328 is bad, software and/ports? And yes I already ordered the a couple of chips. But a couple of problems, I didn't see any software for a MAC in the provided link and I don't have a color display. According to the "Comparative table for clone tester pdf" which I found on this thread( thanks to who did that PDF), it's the M328 Kit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jreyes on April 06, 2019, 02:07:50 pm
Thanks for the input, yes the 328 is bad, software and/ports? And yes I already ordered the a couple of chips. But a couple of problems, I didn't see any software for a MAC in the provided link and I don't have a color display. According to the "Comparative table for clone tester pdf" which I found on this thread( thanks to who did that PDF), it's the M328 Kit.
Software-wise, you'll need CrossPack for AVR: https://www.obdev.at/products/crosspack/index.html (https://www.obdev.at/products/crosspack/index.html) and the Xcode command line tools: http://osxdaily.com/2014/02/12/install-command-line-tools-mac-os-x/ (http://osxdaily.com/2014/02/12/install-command-line-tools-mac-os-x/). You can also use an Arduino board flashed with the ArduinoISP sketch rather than a dedicated USBAsp if you already have one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: fastguido on April 06, 2019, 03:39:53 pm
Thanks for the input, yes the 328 is bad, software and/ports? And yes I already ordered the a couple of chips. But a couple of problems, I didn't see any software for a MAC in the provided link and I don't have a color display. According to the "Comparative table for clone tester pdf" which I found on this thread( thanks to who did that PDF), it's the M328 Kit.
Software-wise, you'll need CrossPack for AVR: https://www.obdev.at/products/crosspack/index.html (https://www.obdev.at/products/crosspack/index.html) and the Xcode command line tools: http://osxdaily.com/2014/02/12/install-command-line-tools-mac-os-x/ (http://osxdaily.com/2014/02/12/install-command-line-tools-mac-os-x/). You can also use an Arduino board flashed with the ArduinoISP sketch rather than a dedicated USBAsp if you already have one.
I have a Ardunio UNO board flashed with ArduinoISP sketch, but how do you put an external program on to another chip ? It seems that in my searches, they talk about loading a Ardunio sketch, not an external program.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Southerner on April 06, 2019, 07:29:09 pm

I have a Ardunio UNO board flashed with ArduinoISP sketch, but how do you put an external program on to another chip ? It seems that in my searches, they talk about loading a Ardunio sketch, not an external program.
Google is your friend.  You will find a gazillion hits telling you how to do this.  In a nutshell,  you build a breadboard and with jumper wires (shown in most of the google hits) to your Uno you "Upload sketch" using your Uno "As Programmer"
OR
If your Uno uses the same AVR chip footprint (28 pin Dip) as the GM328 AVR chip then you simply pull the chip from the Uno and substitute your M328 target chip and load the correct M328 sketch into the Uno.  Once that is done you pull your M328 AVR chip and put the Uno AVR chip back.  If either or both are SMT versions then things change since the ATMega328 smt version is a 32 pin chip whereas the ATMEga328P 28 pin dip version is well 28 pins.  Same chip but one has more pins than the other.

If you can find the ICSP pins on your M328 then your can use an ICSP cable from your Uno to the M328 and program it that way.

Again,  Google is your friend.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on April 06, 2019, 07:33:12 pm
I'd like to suggest that mikrocontroller.net would add info on optimal PCB routing for ZIF sockets. Anyone agree?  :-//

I'm not sure if that would help. We have some hints for clone vendors already (even in Mandarin) and haven't received any feedback from Chinese vendors so far.
A bit of a shame. Hey, if they're all such good copy artist's, you can fix that by favoring illustrations of products that do it right..  :P
Title: Re: $20 LCR ESR Transistor checker project
Post by: fastguido on April 06, 2019, 08:27:47 pm

I have a Ardunio UNO board flashed with ArduinoISP sketch, but how do you put an external program on to another chip ? It seems that in my searches, they talk about loading a Ardunio sketch, not an external program.
Google is your friend.  You will find a gazillion hits telling you how to do this.  In a nutshell,  you build a breadboard and with jumper wires (shown in most of the google hits) to your Uno you "Upload sketch" using your Uno "As Programmer"
OR
If your Uno uses the same AVR chip footprint (28 pin Dip) as the GM328 AVR chip then you simply pull the chip from the Uno and substitute your M328 target chip and load the correct M328 sketch into the Uno.  Once that is done you pull your M328 AVR chip and put the Uno AVR chip back.  If either or both are SMT versions then things change since the ATMega328 smt version is a 32 pin chip whereas the ATMEga328P 28 pin dip version is well 28 pins.  Same chip but one has more pins than the other.

If you can find the ICSP pins on your M328 then your can use an ICSP cable from your Uno to the M328 and program it that way.

Again,  Google is your friend.

Thanks for trying to help me. I have been Googling for 2 hours, no luck on a tutorial on uploading an external file that isn't a "Arduino sketch" .  I can do the breadboard no problem, then what's next ? Where is the  "upload sketch" located and what sketch?  All it is uploading is the ISP sketch to the UNO. Where is the "as Programer" located? I have it set "programmer as ISP" in the pull down menu, is this right?I do not see any tester files under sketch folder, all I see is ArduinoISP.ino . I'm missing something for sure, how do you get the tester file folder into the Ardunio world? Also do you need a Xtal on the M328 on the breadboard ?  Google is not my friend today!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 06, 2019, 09:53:32 pm
Tool chain for Mac: http://www.ladyada.net/learn/avr/setup-mac.html (http://www.ladyada.net/learn/avr/setup-mac.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: fastguido on April 06, 2019, 10:00:44 pm
Tool chain for Mac: http://www.ladyada.net/learn/avr/setup-mac.html (http://www.ladyada.net/learn/avr/setup-mac.html)
What does that link have to do with Arduino? Or do you have additional software plus the Arduino IDE?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on April 06, 2019, 10:31:55 pm
fastguido, in short, after you have ArduinoISP loaded on your Uno, you then have to wire up the Uno to the chip you want to program and use avrdude to upload the binary files from your computer to the chip.

The series of blog posts that begin at the page below will show you how to wire it up and how to use avrdude to set fuse bits and upload files. It goes into details about compiling C code and converting to hex, which you can ignore, and then how to upload the binaries.

https://kwagjj.wordpress.com/2014/07/09/using-arduino-uno-as-an-avr-programmer-basic-concepts/
Title: Re: $20 LCR ESR Transistor checker project
Post by: fastguido on April 06, 2019, 10:37:58 pm
fastguido, in short, after you have ArduinoISP loaded on your Uno, you then have to wire up the Uno to the chip you want to program and use avrdude to upload the binary files from your computer to the chip.

The series of blog posts that begin at the page below will show you how to wire it up and how to use avrdude to set fuse bits and upload files. It goes into details about compiling C code and converting to hex, which you can ignore, and then how to upload the binaries.

https://kwagjj.wordpress.com/2014/07/09/using-arduino-uno-as-an-avr-programmer-basic-concepts/

So is avrdude included in the Ardunio IDE or is it additional software that I have to download?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Southerner on April 07, 2019, 03:26:48 am
So is avrdude included in the Ardunio IDE or is it additional software that I have to download?

Yes, AVR Dude is loaded with Arduino IDE.

AVR Dude is the back end for the Arduino IDE.  In a nutshell,  Arduino IDE is just the GUI interface for AVR Dude.  One gotcha is that Arduino IDE does not support all functions in AVR Dude.  For example,  one item Arduino IDE will not do is allow you to read a current chip.  You can program that chip (in most cases) but you can't read what is currently programmed into that chip.  AVR Dude does load at the same time as Arduino IDE.  If you look up the commands for AVR Dude you will find that you can instruct it to read that chip you just programmed using the command line commands but again you can't  get Arduino IDE to tell AVR Dude to read that chip so if you look up the commands for AVR Dude you can still do the things like reading the chip.  AVR Dude is a pretty versatile program.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on April 07, 2019, 10:51:58 am
I hope someone can help this analog design guy from the past. I have had a Banggood 328 tester for about a couple of years now, been working fine and use it daily. Last week the display wouldn't show any characters, power LED would come on, if I inserted a LED in the test zip it would flash a few times, checked the power supply, ok.  2.5V reference, ok.  So I borrowed a friends same tester and swapped the 328 from his to mine, (thank God for sockets) and it works, so my 328 is bad. I just ordered a couple of new 328's (one for a spare) to replace mine in case it's not just a software problem. This is where I am at this point, I have no knowledge on programming accept some very basic Arduino stuff, I have only a MAC, all the threads on programing the 328 that I have read on this thread are way over my head, it's all Greek to me. Is there someone on here that could program a couple of 328 for me or another idea. Thanks in advance.



You tested the ATMega328p chip and you found it bad? In that case, yes you can order new ATMega328p new chips and program them. Its not so hard! You need
an USPAsp programmer + AVR Board

https://www.ebay.com/itm/Programmer-AVR-Minimum-System-Board-ATMEGA16-ATmega32-USB-ISP-USBasp-For-ATMEL/351110426836?epid=2114364063&hash=item51bfcff0d4:g:fNgAAOxydlFSviwG&frcectupt=true (https://www.ebay.com/itm/Programmer-AVR-Minimum-System-Board-ATMEGA16-ATmega32-USB-ISP-USBasp-For-ATMEL/351110426836?epid=2114364063&hash=item51bfcff0d4:g:fNgAAOxydlFSviwG&frcectupt=true)

Install AVRdude http://savannah.nongnu.org/projects/avrdude (http://savannah.nongnu.org/projects/avrdude) and download the mega328_color_kit version below

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/)

Then just use the command below to program flash and eeprom

avrdude -c usbasp -p m328p -U flash:w:TransistorTester.hex
avrdude -c usbasp -p m328p -U eeprom:w:TransistorTester.eep

Finally program also the efuses with the follow command and you are ready !

avrdude -p m328p -F -P usb -c usbasp - -U lfuse:w:0xFF:m -U hfuse:w:0xD9:m -U efuse:w:0xF4:m -U lock:w:0x0F:m
Thanks for the input, yes the 328 is bad, software and/ports? And yes I already ordered the a couple of chips. But a couple of problems, I didn't see any software for a MAC in the provided link and I don't have a color display. According to the "Comparative table for clone tester pdf" which I found on this thread( thanks to who did that PDF), it's the M328 Kit.

The avrdude works on MAC Os, you can install it following the directions below.
http://macappstore.org/avrdude/ (http://macappstore.org/avrdude/)

No other software is needed. You have just to buy the programmer (or build it with your breadboard+Arduino you already have) which is pretty cheap. If you have my 328p clone AY-AT then you need the mega328_color_kit (I didn't know either that mine was a color version since from the day I bought it, all I was seeing was just black background with green text) otherwise you can try the other version you will find inside the mikrocontroller.net repository.

You can program the MCU as many times you like (actually there is a limit but this is pretty big), so you can try without fear, just be careful with the fuses, because there is the danger to brick (lock) your microcontroller and in that case, you need to re-program the IC with a method called High Voltage Parallel Programming or just HVPP (in case of Mega328p).


Title: Re: $20 LCR ESR Transistor checker project
Post by: fastguido on April 07, 2019, 04:01:52 pm
So, it looks like I have what I need, Ardunio uno, breadboard , Ardunio IDE which also installed Avrdude. But I still do not understand how to get the Hex and eprom file into the ardunio world? Like I keep trying to get across , all the tutorials on using the arduinio as a ISP, show loading the blink sketch into a blank micro which is already in the sketch folder and it's a INO type. I need to know how to get a non INO file into (I guess) the sketch folder, is this right?  Also what is this Makefile thing? Does it have to be loaded into the sketch too. And how do load/start  Avrdude, which you guys say is included in the Ardunio IDE, I didn't see it anywhere in the menu's? Totally frustrated! Why can't this stuff be drag and drop!
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on April 07, 2019, 06:17:57 pm
So, it looks like I have what I need, Ardunio uno, breadboard , Ardunio IDE which also installed Avrdude. But I still do not understand how to get the Hex and eprom file into the ardunio world? Like I keep trying to get across , all the tutorials on using the arduinio as a ISP, show loading the blink sketch into a blank micro which is already in the sketch folder and it's a INO type. I need to know how to get a non INO file into (I guess) the sketch folder, is this right?  Also what is this Makefile thing? Does it have to be loaded into the sketch too. And how do load/start  Avrdude, which you guys say is included in the Ardunio IDE, I didn't see it anywhere in the menu's? Totally frustrated! Why can't this stuff be drag and drop!

The *.hex and *.eep files are there and they are the compiled files from the C sources (*.ino files) that are also there. Just get the compiled files and use them.

AVRdude is called automatically when you upload the bin files to the Arduino. You need explicitly call the AVRdude in the command line when you are not using Arduino IDE. Only in the last case you need to write the AVRdude command I wrote in an older post.

Title: Re: $20 LCR ESR Transistor checker project
Post by: fastguido on April 07, 2019, 06:50:11 pm
"Just get the compiled files and use them", could you clarify that statement-How do you do that?, I don't understand.  How do I upload the bin files to the Arduino IDE?  Where do I put them in the Arduino IDE?   I have downloaded the file folder called Component-tester 1.34m, there are tons of files, which files do I use?  There is a ton of .c ,.h, files, I see no .eep files.  Am I to assume that the .h is the .hex files? I have the M328kit as shown in the previously posted PDF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on April 08, 2019, 07:37:38 pm
"Just get the compiled files and use them", could you clarify that statement-How do you do that?, I don't understand.  How do I upload the bin files to the Arduino IDE?  Where do I put them in the Arduino IDE?   I have downloaded the file folder called Component-tester 1.34m, there are tons of files, which files do I use?  There is a ton of .c ,.h, files, I see no .eep files.  Am I to assume that the .h is the .hex files? I have the M328kit as shown in the previously posted PDF.

No, *.h files are not *.hex. The *.h are headers for the C source files *.c and you can open them with a text editor. The *.hex files (you can also open it) are machine commands for the MCU and they are in hexadecimal text format.

Inside the repository https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/) you will find the *.hex and *.eep files for the mega328 color display. If you go to the parent directory you will find other versions (*.hex and *.epp) as well as all the source files (*.h and *.c)

You can always use the *.c files but you have to re-compile. If you want to re-compile from the sources, then you have to use the Arduino IDE, but instead, if you want to use directly the *.hex and *.eep files, you have to use the command line AVRDude+external programmer (like USBAsp) without the Arduino hardware or IDE itself.

Of course it is possible to use the Arduino UNO as a Programmer and the breadboard with ATMega328p connected, but personally, I did not use it before. You can find more info for the last solution at

https://www.arduino.cc/en/Tutorial/ArduinoToBreadboard (https://www.arduino.cc/en/Tutorial/ArduinoToBreadboard)
https://www.youtube.com/watch?v=35hB-sn0ddI (https://www.youtube.com/watch?v=35hB-sn0ddI)
https://www.instructables.com/id/Program-ATmega-328-Using-Arduino-Arduino-As-ISP/ (https://www.instructables.com/id/Program-ATmega-328-Using-Arduino-Arduino-As-ISP/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: powersola on April 12, 2019, 12:16:14 pm
Hi everybody.

it's been a while (like 2 years) that I want to buy a meter like this but I always postponed for various reasons.

I did read the thread in this long time, and I am asking you if something changed speaking about models/revisions.
I had in plan to get one of these (seems the same, just different color?).

(https://ae01.alicdn.com/kf/HTB1tqwwdx1YBuNjy1zcq6zNcXXaV.jpg)

(https://ae01.alicdn.com/kf/HTB19QqROpXXXXXVXVXXq6xXFXXXH/228872671/HTB19QqROpXXXXXVXVXXq6xXFXXXH.jpg)

Is there anything better as of 2019, keeping in mind that I'd like to use one of the enhanced firmwares?


Have a nice day,
Chicco
Title: Re: $20 LCR ESR Transistor checker project
Post by: towe96 on April 12, 2019, 12:55:02 pm
The one with the black PCB seems to be pre-assembled (?), since it mostly uses SMD parts.

You might want to check whether it also uses a SMD version of the ATmega328P microcontroller, or if it still uses the more conventional DIP version.
If it's the SMD version, you might find it harder to flash new firmware onto it via SPI compared to just removing the DIP package from its socket and plugging it into a breadboard.

I own the red AY-AT variant.
Title: Re: $20 LCR ESR Transistor checker project
Post by: powersola on April 12, 2019, 01:04:03 pm
The one with the black PCB seems to be pre-assembled (?), since it mostly uses SMD parts.

You might want to check whether it also uses a SMD version of the ATmega328P microcontroller, or if it still uses the more conventional DIP version.
If it's the SMD version, you might find it harder to flash new firmware onto it via SPI compared to just removing the DIP package from its socket and plugging it into a breadboard.

I own the red AY-AT variant.

Thank you towe96.

Apart from "Preassembled/Kit", and "SMD/DIP atmega 328P" any other difference between these kind of models? I'll try to catch one with DIP 328p for sure, but in case I can't find one no problem to program via SPI.
Any modification needed/suggested required to the board?

Never knew what "AY-AT" variant is reffered to, but from what you say It seems that the ones I linked are quite great for what I want to do.

Have a nice day,
Chicco
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2019, 02:06:55 pm
Both are AY-AT based clones. There are also a few testers with ATmega 644 (more flash) but they don't use the additional I/O pins for hardware options. At the moment the AY-AT is still the best choice when buying. If you want all the cool stuff you have to DIY.
Title: Re: $20 LCR ESR Transistor checker project
Post by: boffin on April 12, 2019, 04:29:25 pm
Both are AY-AT based clones. There are also a few testers with ATmega 644 (more flash) but they don't use the additional I/O pins for hardware options. At the moment the AY-AT is still the best choice when buying. If you want all the cool stuff you have to DIY.

Is there a wiki/docs somewhere that maps the common asian boards to the build parameters required for the current firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2019, 05:25:40 pm
Karl-Heinz provides a precompiled k-firmware for several clones (see the Makefile for settings). For the m-firmware you'll find settings for a few clones in the "Clones" file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: powersola on April 15, 2019, 08:47:47 am
Both are AY-AT based clones. There are also a few testers with ATmega 644 (more flash) but they don't use the additional I/O pins for hardware options. At the moment the AY-AT is still the best choice when buying. If you want all the cool stuff you have to DIY.

Thanks, nice.
If it's still the best choice I'll go with it ;)

also "boffin" asked a good thing. I extend that question to know if there's some wiki/repo where we can find the possible/recommended modification, even hardware ones. No problems DIYing ;)

Thank you all for the great info.
Chicco
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 15, 2019, 10:19:56 am
Karl-Heinz' documentation is a good starting point: https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on April 15, 2019, 11:34:02 am
What are the main differences between K and M versions ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 15, 2019, 02:02:18 pm
The differences are explained in the m-firmware's README file. The m-firmware doesn't support the SamplingADC, but it offers an IR RC decoder, IR RC sender, dedicated optocoupler check, servo check, OneWire (DS18B20), touchscreen, remote control interface via serial port, and some measurements/checks are done a little bit different.
Title: Re: $20 LCR ESR Transistor checker project
Post by: sdancer75 on April 15, 2019, 04:51:49 pm
The differences are explained in the m-firmware's README file. The m-firmware doesn't support the SamplingADC, but it offers an IR RC decoder, IR RC sender, dedicated optocoupler check, servo check, OneWire (DS18B20), touchscreen, remote control interface via serial port, and some measurements/checks are done a little bit different.

Can't find the Readme file, can you point me the exact url link?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 15, 2019, 05:21:01 pm
The README file is in the tar.gz source code package.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 17, 2019, 05:59:51 pm
Does someone with a ST7036 display like to test the m-firmware's new ST7036 driver?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chriss on May 09, 2019, 10:39:43 pm
Hi!
I got yesterday my new, clone measuring tool from ebay, where I don't know which is my version of my FW.
I read lot posts here and sorry if I jump over the answer...

I have several questions because I'm really confused now:

I found this link with great resources about this tool ( probably most of you know this link ):
https://yadi.sk/d/yW8xa5NJgUo5z (https://yadi.sk/d/yW8xa5NJgUo5z)

There is two jpg, one is labeled with:
LCR-T4(T3)NoStripGreed ( actually this is my hardware )

And one is labeled with:
LCR-T4(T3)StripGreed

So, what this means "StripGreed" & "NoStripGreed" ?

Which version of firmware is maybe better? Or how to determine the right version?
1.13K or 1.13M ?
Or even can I mix up the versions?

Now I have an 8MHz oscillator on my pcb, is it prefferable to change it to 16MHz?
I can see there is the same unit with 8 and 16MHz osc...

Thank you for any suggestion.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 10, 2019, 08:11:02 am

I have several questions because I'm really confused now:

I found this link with great resources about this tool ( probably most of you know this link ):
https://yadi.sk/d/yW8xa5NJgUo5z (https://yadi.sk/d/yW8xa5NJgUo5z)

There is two jpg, one is labeled with:
LCR-T4(T3)NoStripGreed ( actually this is my hardware )

And one is labeled with:
LCR-T4(T3)StripGreed

So, what this means "StripGreed" & "NoStripGreed" ?


Whether attentively you read the user guide from the author?
https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/)
It is necessary to read STRIP GRID, but not STRIPGREED
On page 10 of a manual there is a description:
"The software can follow to another pin assignment of port D for a simpler connection of the LCD display. The following table 2.2 shows the modifies assignments for the strip grid layout and the alternativ connection of a graphical display for the micocontrollers ATmega328."Compare schematic circuits on these clones and you will see a difference in connection of the display to PD ports.
In a manual there are also answers to other your questions. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chriss on May 10, 2019, 10:33:47 am
Oh, my fault, thank you so much for this explanation.
I didn't got for what is that "strip grid" standing for.

I will re-read again that doc from the link you sent.

Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 10, 2019, 10:49:41 am
Which version of firmware is maybe better? Or how to determine the right version?
1.13K or 1.13M ?
Or even can I mix up the versions?

The current m-firmware is 1.35m (soon 1.36m ;) ). The README file of the m-firmware explains the differences briefly. The main difference is that the k-firmware supports the SamplingADC for measuring low value caps and coils, and that the m-firmware offers several additional features like IR RC receiver/decoder, IR RC sender, servo tester and so on. I'd suggest to get another tester and run both firmwares.

Now I have an 8MHz oscillator on my pcb, is it prefferable to change it to 16MHz?
I can see there is the same unit with 8 and 16MHz osc...

Yes, it doubles the limit of anything frequency related and improves time related measurements, e.g. max. squarewave frequency, frequency counter and inductance measurement. It also speeds up the display output (matters for color displays).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 10, 2019, 01:31:56 pm
Hi,

I have a GM328A+TFT. I want to install the firmware 1.34mRus(8MHz).zip from CloneTtester. I have create a new folder and i've decrompressed the file from ComponentTester-1.35m. After i've decompressed the firmware 1.34mRus(8MHz).zip in this folder. I replaced the for english in my config.h.
I open with WinAVR Makefile and follow the WINAVR [Make All]. But i have these errors.

> "make.exe" all
      0 [main] sh 9940 sync_with_child: child 5456(0x1D8) died before initialization with status code 0xC0000142
  57296 [main] sh 9940 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
avr-gcc -mmcu=atmega328 -Wall -mcall-prologues -I. -Ibitmaps -DF_CPU=8000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT main.o -MF dep/main.o.d -c main.c
main.c: In function 'main':
main.c:1239:3: error: 'POWER_DDR' undeclared (first use in this function)
   POWER_DDR = (1 << POWER_CTRL);        /* set pin as output */
   ^
main.c:1239:3: note: each undeclared identifier is reported only once for each function it appears in
main.c:1240:3: error: 'POWER_PORT' undeclared (first use in this function)
   POWER_PORT = (1 << POWER_CTRL);       /* set pin to drive power management transistor */
   ^
main.c:1331:9: error: 'BUTTON_PIN' undeclared (first use in this function)
   if (!(BUTTON_PIN & (1 << TEST_BUTTON)))    /* test button pressed */
         ^
make.exe: *** [main.o] Error 1

> Process Exit Code: 2

See lines:

 Line 1239 POWER_DDR = (1 << POWER_CTRL);        /* set pin as output */
 Line 1240 POWER_PORT = (1 << POWER_CTRL);       /* set pin to drive power management transistor */
 Line 1331   if (!(BUTTON_PIN & (1 << TEST_BUTTON)))    /* test button pressed */

Thanks for your help and sorry for my english  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 10, 2019, 02:12:22 pm
Presumably you're using an outdated config_328.h.

From the CHANGES file for 1.35m:
- Separated pin configuration for test push button and power control
  (CONTROL_PORT -> POWER_PORT and BUTTON_PORT).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 10, 2019, 02:40:24 pm
Hi,

I use the config_328 included in ComponentTester-1.35m.

With rotary does anyone know what we can do ?

Thanks

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 10, 2019, 02:52:33 pm
Do you have following in your config_328.h?
Code: [Select]
/*
 *  power control
 */

#define POWER_PORT       PORTD     /* port data register */
#define POWER_DDR        DDRD      /* port data direction register */
#define POWER_CTRL       PD6       /* controls power (1: on / 0: off) */


/*
 *  test push button
 */

#define BUTTON_PORT      PORTD     /* port data register */
#define BUTTON_DDR       DDRD      /* port data direction register */
#define BUTTON_PIN       PIND      /* port input pins register */
#define TEST_BUTTON      PD7       /* test/start push button (low active) */

For the rotary encoder (GM328A is AY-AT):
Code: [Select]
#define ENCODER_PORT     PORTD     /* port data register */
#define ENCODER_DDR      DDRD      /* port data direction register */
#define ENCODER_PIN      PIND      /* port input pins register */
#define ENCODER_A        PD1       /* rotary encoder A signal */
#define ENCODER_B        PD3       /* rotary encoder B signal */

and in config.h:
Code: [Select]
#define HW_ENCODER
#define ENCODER_PULSES   4              /* usually 4 pulses per step */
#define ENCODER_STEPS    20             /* usually 20 detents */
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 10, 2019, 04:00:38 pm
Hi madires,

I modified all parameters and now i have a new error.

         0 [main] sh 12708 sync_with_child: child 1236(0x1CC) died before initialization with status code 0xC0000142
  59229 [main] sh 12708 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
avr-gcc -mmcu=atmega328 -Wall -mcall-prologues -I. -Ibitmaps -DF_CPU=8000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT main.o -MF dep/main.o.d -c main.c
In file included from main.c:24:0:
config.h:802:26: error: 'CAP_PCB' undeclared here (not in a function)
 #define C_ZERO           CAP_PCB + CAP_WIRES + CAP_PROBELEADS
                          ^
variables.h:108:31: note: in expansion of macro 'C_ZERO'
     #define NV_C_ZERO         C_ZERO
                               ^
variables.h:112:77: note: in expansion of macro 'NV_C_ZERO'
   const Adjust_Type     NV_Adjust_1 EEMEM = {R_MCU_LOW, R_MCU_HIGH, R_ZERO, NV_C_ZERO, UREF_OFFSET, COMPARATOR_OFFSET, LCD_CONTRAST, 0};
                                                                             ^
make.exe: *** [main.o] Error 1

> Process Exit Code: 2


Thanks for your help

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 10, 2019, 05:27:03 pm
All errors are caused by using the header files of the old firmware version. The next issue can be fixed by editing config.h. Replace
Code: [Select]
#define C_ZERO           CAP_PCB + CAP_WIRES + CAP_PROBELEADS
with
Code: [Select]
#define C_ZERO           43
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 10, 2019, 06:02:01 pm
Hi..... again me

Now the error is:

> "make.exe" all
      0 [main] sh 896 sync_with_child: child 10748(0x1CC) died before initialization with status code 0xC0000142
  47571 [main] sh 896 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
avr-gcc -mmcu=atmega328 -Wall -mcall-prologues -I. -Ibitmaps -DF_CPU=8000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT main.o -MF dep/main.o.d -c main.c
main.c:1913:1: fatal error: opening dependency file dep/main.o.d: No such file or directory
 }
 ^
compilation terminated.
make.exe: *** [main.o] Error 1

> Process Exit Code: 2

Thanks x 100
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 10, 2019, 06:25:19 pm
That looks like the tool chain has a problem. If it's cygwin try to run it as admin.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 10, 2019, 07:34:07 pm
hi,

When you copy AVR Toolchain in WinAVR folder, do you owerwrite the same filles or ignore ?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: eas on May 11, 2019, 01:58:01 am
A quick warning to others.

I recently ordered a kit version of the AY-AT tester from this ebay listing (https://www.ebay.com/itm/2019-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator/172557508334).

It came today and I was disappointed that the all the resistors were loose, rather than still in the paper tape. As a result I measured each resistor with a DMM rather than trying to read the markings. In the process I discovered that the key measurement resistors, which should have 0.1% tolerances, and which were color coded as having 0.1% tolerances were way way off!

The 3x 470K Ohm 0.1% resistors measure 487K Ohm 503K Ohm and 520K Ohm.  That's an error of 3.6% 7.0% and 10.6%!
The 3x 680 Ohm 0.1% resistors measure 671 (-1.3%), 661(-2.8%) & 674 (-0.8%).

It's odd, because none of the other resistors in the kit were anywhere near as far off.

I've requested replacements.

Has anyone else had a similar experience?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on May 11, 2019, 02:23:55 am
Hey eas! Good to see you.

My tester from several years ago had a couple of those resistors out of tolerance, but not by that much. So, I just arranged them to minimize the total error in their ratios.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on May 11, 2019, 06:47:05 am
hi,

When you copy AVR Toolchain in WinAVR folder, do you owerwrite the same filles or ignore ?

Thanks

Hello Andbro.

Maybe this will help you:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1729157/#msg1729157 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1729157/#msg1729157)

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 11, 2019, 01:52:58 pm
Hi,

I have always this error with WinAVR . I have try with 2 others computers and i have the same error.

> "make.exe" all
      0 [main] sh 3716 sync_with_child: child 11016(0x1E8) died before initialization with status code 0xC0000142
  40724 [main] sh 3716 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
avr-gcc -mmcu=atmega328 -Wall -mcall-prologues -I. -Ibitmaps -DF_CPU=8000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT main.o -MF dep/main.o.d -c main.c
main.c:1565:1: fatal error: opening dependency file dep/main.o.d: No such file or directory
 }
 ^
compilation terminated.
make.exe: *** [main.o] Error 1


Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 11, 2019, 02:46:16 pm
Andbro
If you installed Windows 8 or Windows 10, then on my resource there is a HELP folder in which is all necessary for the correct work of WinAVR. https://yadi.sk/d/yW8xa5NJgUo5z/Help/Editing%20and%20compilation%20of%20a%20firmware
Read attentively the Readme En.txt file - I hope that it will help you to solve a problem with compilation. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 11, 2019, 03:18:48 pm
Hi,

If I want to use Markus firmware 1.30 does I extract the files of the folder "ComponentTester-1.30m" in Trunk folder.. I have never try to modify a Markus firmware.

Many thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 11, 2019, 04:20:26 pm
Andbro, the instruction in Readme En.txt is a step-by-step installation of software and compilation for k - firmware.
For compilation of  m - firmware there is no need to create the Trunk folder and to leave the dep folder. You need just to unpack relevant archive "ComponentTester-1.35m"
further to carry out necessary settings in files of a configuration as prompted dear madires.
Then to start compile process. Everything is very simple. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 11, 2019, 04:35:31 pm
Hi,

I have unpacked the version 1.35m, modify config.h and config_328.h.
When I Make All with WinAVR, I have this error. I have try on other computer and it's the same error.

 "make.exe" all
      0 [main] sh 3716 sync_with_child: child 11016(0x1E8) died before initialization with status code 0xC0000142
  40724 [main] sh 3716 sync_with_child: *** child state waiting for longjmp
/usr/bin/sh: fork: Resource temporarily unavailable
avr-gcc -mmcu=atmega328 -Wall -mcall-prologues -I. -Ibitmaps -DF_CPU=8000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT main.o -MF dep/main.o.d -c main.c
main.c:1565:1: fatal error: opening dependency file dep/main.o.d: No such file or directory
 }
 ^
compilation terminated.
make.exe: *** [main.o] Error 1

I'm thinking I will abort...

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 11, 2019, 08:29:16 pm
Hi,

Sorry, it's my mistake. I have forgotten to replace the msys-1.0.dll in WinAVR\utils\bin\. |O


Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 11, 2019, 08:38:47 pm
Hi,

I have tried to changed the language for english for my GM328A 8Mhz in the firmware of Clone Ttester, "1.30mRus(8MHz).zip".
When i Make All in WinAVR, i have this message. Does anyone can help me ?
I use the packed file, ComponentTester-1.30m.tgz.

extras.c: In function 'Servo_Check':
extras.c:793:10: error: 'RUN_FLAG' undeclared (first use in this function)
   Flag = RUN_FLAG | MODE_PULSE | CHANGE_PULSE | CHANGE_FREQ | UPDATE_FREQ | UPDATE_PULSE | UPDATE_FREQ;
          ^
extras.c:793:10: note: each undeclared identifier is reported only once for each function it appears in
make.exe: *** [extras.o] Error 1

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 11, 2019, 09:18:18 pm
That is a known issue and was fixed in a later version. Add following in Servo_Check() in extras.c:
Code: [Select]
  #define RUN_FLAG       0b00000001     /* run / otherwise end */

Why are you using an old firmware version?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 11, 2019, 09:34:38 pm
It's time for a new version of the m-firmware. ;)

v1.36m:
- Added optional 6x8 font to ST7565R driver.
- Added optional mainmenu item to power off tester (SW_POWER_OFF).
- Integrated battery monitoring into TestKey() and Zener_Tool().
- Added detection of two short presses of the test key to TestKey() and removed
  redundant functionality in multiple functions to reduce firmware size.
- Driver for ST7036 based displays (4-bit parallel & 4-wire SPI, untested).
- Moved power control and battery monitoring to dedicated functions for
  better integration with other functions.
- Driver for PCF8814 based displays (3-line SPI, thanks to Mahmoud Laouar
  for testing).
- Driver for STE2007/HX1230 based displays (3-line SPI).
- Fixed bug in LCD_Clear() of PCD8544 driver.
- Added missing cyrillic font to ST7565R driver (reported by Andrey@EEVblog).
- Updated font_8x16_cyrillic_vfp.h (thanks to Andrey@EEVblog).
- Fixed issue with bad character in font_HD44780_cyr.h.

Please visit https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware for downloading the new version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on May 12, 2019, 09:05:50 am
Hello madires.

Update for firmware m of the Spanish language for all those interested with the latest news introduced by the master madires.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 12, 2019, 05:44:45 pm
Hi,

What is the right fuses for a GM328A ?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on May 12, 2019, 08:56:22 pm
Hi Andbro,

...try Fuses:

                   Low 0xF7
                   High 0xD9
                   Ext   0xFC

                   LB    0xFF

Greetings Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 12, 2019, 10:21:53 pm
Hi,

I have modify the new Markus firmware 1.36 for my GM328A (AY-AT). I don't find where is my errors. The screen turn ON without text. I have checked my LCD 7735 parameters but i don't find an error.
I post my config.h and config_328.h.

Thanks for your help

A newbie...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on May 12, 2019, 11:09:41 pm
Hi Andbro,

... first sorry for my bad english!!

next, i see in your config_328.h is activatet the ST7565R Display? What for a Display you used in your Tester?
If it is the 7735 Display, you have configured the wrong.

/*
 *  ST7735, SPI interface (bit-bang, 4 wire)
 */

//#if 0
#define LCD_ST7735                      /* display controller ST7735 */
#define LCD_GRAPHIC                     /* graphic display */
#define LCD_COLOR                       /* color display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RES          PD0            /* port pin used for /RESX (optional) */
#define LCD_CS           PD5            /* port pin used for /CSX (optional) */
#define LCD_DC           PD1            /* port pin used for D/CX */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SDA          PD3            /* port pin used for SDA */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       160            /* number of vertical dots */
#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_ROTATE                      /* switch X and Y (rotate by 90°) */
//#define LCD_OFFSET_X     4               /* enable x offset of 2 or 4 dots */
//#define LCD_OFFSET_Y     2               /* enable y offset of 1 or 2 dots */
#define LCD_LATE_ON                     /* turn on LCD after clearing it */
#define FONT_10X16_HF                   /* 10x16 font, horizontally aligned & flipped */
//#define FONT_8X16_CYRILLIC_HF           /* 8x16 cyrillic font, horizontally aligned & flipped */
#define SYMBOLS_30X32_HF                /* 30x32 symbols, horizontally aligned & flipped */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SDA        /* port pin used for MOSI */
//#endif

/*
 *  rotary encoder
 */

#define ENCODER_PORT     PORTD     /* port data register */
#define ENCODER_DDR      DDRD      /* port data direction register */
#define ENCODER_PIN      PIND      /* port input pins register */
#define ENCODER_A        PD3       /* rotary encoder A signal */
#define ENCODER_B        PD1       /* rotary encoder B signal */

if it is the GeekTeches Board.

Greetings Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 12, 2019, 11:36:07 pm
Hi,

Sorry me too for my english :). I use a ST7735 like display. And myself, i'm a newbie but i try hard....

/*
 *  ST7565R, SPI interface (bit-bang)
 *  - settings for Electronic Assembly EA DOGM/DOGL128-6
 *  - uses LCD_CS to support rotary encoder in parallel at PD2/3
 */

//#if 0

I must add or remove // for activated a display?

Best regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on May 12, 2019, 11:54:00 pm
... you have to add!

See the differents in my post  above, there is another portorder if your Bord is the GeekTeches .

Best regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 13, 2019, 12:02:47 am
Hi Obelix,

It's working well.  :D

Is it OK section ?

/*
 *  increase/decrease push buttons
 */

#define KEY_PORT         PORTD     /* port data register */
#define KEY_DDR          DDRD      /* port data direction register */
#define KEY_PIN          PIND      /* port input pins register */
#define KEY_INC          PD1       /* increase push button (low active) */
#define KEY_DEC          PD3       /* decrease push button (low active) */

Thanks a lot

Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on May 13, 2019, 12:17:07 am
Hi,

... did you have no rotary encoder on the Testerboard? Can you make a picture ?

If it is another board as the Geek, i ‚m not shure about the portorder, so you have to test it.

Regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 13, 2019, 12:23:15 am
Hi Obelix,

It's not a GeekTeches boards. My other is ESR GM328A is a GeekTeches.
The rotary work very well.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: chansw on May 14, 2019, 04:36:32 am
Hi, everybody! :D
I picked up a new firmware revision 790  from Karl-Heinz  for the device BsideESR02 and DTU-1701. In archive 2 firmwares with English language and a font 8x12 and 8x15, different in thickness. The bootpage for convenient use of a device is also a little edited.In the photo 2 different versions fonts of a firmware with Russian are only for evident comparing.

indman, how are you programming the firmware, are you desoldering the Atmega 328 and programming it out of circuit?

Jerry
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 14, 2019, 09:13:51 am
chansw,no, this photo will help you? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on May 14, 2019, 07:22:29 pm
hi guys please help

i running firmware that was given by perieanuo in this forum.  ver 1.29m  my tester uses atmega328p-pu ic.
I  tried to run adjustment from the menu half way it display error! now it always display battery? 2: 6mv sometimes 1: 6mv.
i try to reprogram my ic and still it show that same thing.
can anyone help? what's wrong?

btw if anyone have a newer version for this device care to share mine is using 8Mhz crystal.

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2019, 10:55:42 am
When the tester is trying to discharge a component but the voltage doesn't drop below a specific threshold (CAP_DISCHARGED, default value 2mV) then it will display that message stating the voltage. This may happen when connecting a battery or a charged cap with very high capacitance. In some cases it could be also caused by powering the tester from a SMPS or by a leakage current on the PCB (dirt?). Have you tested a film cap (100nF - 2.2µF) three times before running the self-adjustment?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 15, 2019, 11:00:04 am
Hi,

I try with AVRDUDESS under windows to write FC for the extended fuse, but AVRDUDESS read always 0x04 ?

Thanks :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2019, 11:03:26 am
That's a known issue of avrdude's configuration file. Simply ignore it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on May 15, 2019, 02:00:24 pm
When the tester is trying to discharge a component but the voltage doesn't drop below a specific threshold (CAP_DISCHARGED, default value 2mV) then it will display that message stating the voltage. This may happen when connecting a battery or a charged cap with very high capacitance. In some cases it could be also caused by powering the tester from a SMPS or by a leakage current on the PCB (dirt?). Have you tested a film cap (100nF - 2.2µF) three times before running the self-adjustment?

so what is the soloution? is my IC broke again?

or my tester broken?

anyway can i use a probe to test component instead of desoldering the component and put it on the tester?

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2019, 04:52:35 pm
Have you tested a film cap (100nF - 2.2µF) three times before running the self-adjustment? Do you power your tester with a SMPS?
Title: Re: $20 LCR ESR Transistor checker project
Post by: stj on May 15, 2019, 05:17:33 pm
use 220nF,
if you use 100nF and it's actually 97nF it will fail - it must really be 100nF or higher, using a 220nF eliminates the risk.
(yes, i learned the hard way!)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 15, 2019, 08:11:21 pm
Hi, madires!
I updated the file of Russian language var_russian.h for 1.36m. :)
I have a question - whether it is possible to move several variables from the variables.h file to the var_language.h file? It is about Tester_str, PWM_str, Hertz_str, CTR_str
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 16, 2019, 09:20:27 am
I have a question - whether it is possible to move several variables from the variables.h file to the var_language.h file? It is about Tester_str, PWM_str, Hertz_str, CTR_str

It's possible. I'll think about it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on May 17, 2019, 01:31:23 pm
Hello Madires.

I am looking for the file where this symbol is> flashing to try a small modification.
It appears when the meter starts at the beginning and if we turn the selector to the left we enter the menu.

Thank you

(http://s2.subirimagenes.com/otros/previo/thump_989821220190517150857-copi.jpg) (http://www.subirimagenes.com/otros-20190517150857copi-9898212.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 17, 2019, 04:39:37 pm
The blinking symbol is meant to indicate that the tester is waiting for a key press to continue. The blinking is generated by TestKey() in user.c. The symbol is created by LCD_Cursor() in each display driver.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on May 17, 2019, 04:48:46 pm
Then it is possible to replace the symbol> with something like this: <Menu / test>

Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 17, 2019, 07:01:19 pm
Yes, for large displays. I'll put your idea on my to-do list.
Title: Re: $20 LCR ESR Transistor checker project
Post by: szpila on May 18, 2019, 11:45:11 am
Hi Madires.

Sending updated lang file for polish language.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N1cho on May 20, 2019, 02:01:53 pm
Have you tested a film cap (100nF - 2.2µF) three times before running the self-adjustment? Do you power your tester with a SMPS?

thanks

I used two serial li-on battery to power up my tester and 12v adaptor to charge the li-on and use the device while charging.
i finally remove the  svr5-04 and my tester work quite normal although sometimes it still display some test value when nothing is on the tester.

anyway the original firmware was 1.13k and i now used someone share to me 1.29m. i tried to recopy the original firmware but i guess it was lock.

i tried many other firmware but when i put the newly burn ic i just when blank i guess those firmware aren't compatible with my tester.

so anyone while to share a newer version, in english after 1.29m my tester use 8Mhz crystal.


thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheOnlyDocc on May 22, 2019, 12:06:04 pm
Hello, I have a question.
I am searching for a new Component Tester. Because i play a lot with smd leds i would prefer a tester with pads where i can press the led against.
Like the ESR02PRO (https://www.aliexpress.com/item/32963716330.html?transAbTest=ae803_5&cv=34252583&ws_ab_test=searchweb0_0%252Csearchweb201602_9_10065_10068_10547_319_317_10548_10696_10084_453_10083_454_10618_10304_10307_10820_10821_537_10302_536_10843_10059_10884_10887_321_322_10103%252Csearchweb201603_53%252CppcSwitch_0&algo_pvid=7f8b7243-92ef-48fb-8459-0b37f823defd&af=3233883_389&cn=42prwg5wxc85dgqua3asv4n8zvbbo4ch&dp=v5_42prwg5wxc85dgqua3asv4n8zvbbo4ch&algo_expid=7f8b7243-92ef-48fb-8459-0b37f823defd-28&scm=1007.22893.125764.0&pvid=99db2b19-147a-4aff-bcf6-7e7385199e7e&onelink_thrd=0.0&onelink_page_from=ITEM_DETAIL&onelink_item_to=32963716330&onelink_duration=0.884661&onelink_status=noneresult&onelink_item_from=32963716330&onelink_page_to=ITEM_DETAIL&afref=https%253A%252F%252Fwww.aliexpress.com%252Fwholesale&aff_platform=default&cpt=1558517972474&sk=ccfBY4yg&aff_trace_key=5cfb6ab6e6a14ef899be78bd6ce2e025-1558517972474-02085-ccfBY4yg&terminal_id=a368af8ffbc342058a57d2acb432b91e (https://www.aliexpress.com/item/32963716330.html?transAbTest=ae803_5&cv=34252583&ws_ab_test=searchweb0_0%252Csearchweb201602_9_10065_10068_10547_319_317_10548_10696_10084_453_10083_454_10618_10304_10307_10820_10821_537_10302_536_10843_10059_10884_10887_321_322_10103%252Csearchweb201603_53%252CppcSwitch_0&algo_pvid=7f8b7243-92ef-48fb-8459-0b37f823defd&af=3233883_389&cn=42prwg5wxc85dgqua3asv4n8zvbbo4ch&dp=v5_42prwg5wxc85dgqua3asv4n8zvbbo4ch&algo_expid=7f8b7243-92ef-48fb-8459-0b37f823defd-28&scm=1007.22893.125764.0&pvid=99db2b19-147a-4aff-bcf6-7e7385199e7e&onelink_thrd=0.0&onelink_page_from=ITEM_DETAIL&onelink_item_to=32963716330&onelink_duration=0.884661&onelink_status=noneresult&onelink_item_from=32963716330&onelink_page_to=ITEM_DETAIL&afref=https%253A%252F%252Fwww.aliexpress.com%252Fwholesale&aff_platform=default&cpt=1558517972474&sk=ccfBY4yg&aff_trace_key=5cfb6ab6e6a14ef899be78bd6ce2e025-1558517972474-02085-ccfBY4yg&terminal_id=a368af8ffbc342058a57d2acb432b91e).
In the past i used one of these https://www.aliexpress.com/item/32950131041.html?spm=a2g0o.detail.1000060.3.520e7bcbR3CFoI&gps-id=pcDetailBottomMoreThisSeller&scm=1007.13339.90158.0&scm_id=1007.13339.90158.0&scm-url=1007.13339.90158.0&pvid=b7a51194-cfa0-474d-ba2a-f3d814a2eda0 (https://www.aliexpress.com/item/32950131041.html?spm=a2g0o.detail.1000060.3.520e7bcbR3CFoI&gps-id=pcDetailBottomMoreThisSeller&scm=1007.13339.90158.0&scm_id=1007.13339.90158.0&scm-url=1007.13339.90158.0&pvid=b7a51194-cfa0-474d-ba2a-f3d814a2eda0) but without the case it did not survived the last move to my new apartment.
Is there another tester with smd pads that is better than the ESR02PRO.
Or is there a Contact PCB available to use with a TC-T7?
Which one is the better meter TC-T7 or ESR02PRO?
What is the difference between TC-T7 and TC-T7-H?
Sorry i know that i have a lot of questions!
Title: Re: $20 LCR ESR Transistor checker project
Post by: trinhvanthien on May 24, 2019, 04:10:59 am
Hi
How to adjust the bold and bigger fonts?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 24, 2019, 08:00:18 am
For the ST7735 you can choose between FONT_10X16_HF, FONT_8X8_HF and FONT_8X16_CYRILLIC_HF (in config_328.h) at the moment. It's also possible to convert some other font. The font file structure is quite simple, but you need to create a few special characters manually (chars 0x01 - 0x07).
Title: Re: $20 LCR ESR Transistor checker project
Post by: mikerj on May 24, 2019, 12:09:01 pm
A quick warning to others.

I recently ordered a kit version of the AY-AT tester from this ebay listing (https://www.ebay.com/itm/2019-TFT-GM328-Transistor-Tester-Diode-LCR-ESR-meter-PWM-Square-wave-Generator/172557508334).

It came today and I was disappointed that the all the resistors were loose, rather than still in the paper tape. As a result I measured each resistor with a DMM rather than trying to read the markings. In the process I discovered that the key measurement resistors, which should have 0.1% tolerances, and which were color coded as having 0.1% tolerances were way way off!

The 3x 470K Ohm 0.1% resistors measure 487K Ohm 503K Ohm and 520K Ohm.  That's an error of 3.6% 7.0% and 10.6%!
The 3x 680 Ohm 0.1% resistors measure 671 (-1.3%), 661(-2.8%) & 674 (-0.8%).

It's odd, because none of the other resistors in the kit were anywhere near as far off.

I've requested replacements.

Has anyone else had a similar experience?

I'm not aware of any of the Chinese kits coming with precision resistors, it's one of the recommended upgrades.  Not really surprising for a $10 kit, since 1/4watt 0.1% precision through hole resistors are around $1 each.

Measure the output of the included 5v regulator if you intend to use it (another recommended upgrade),  the garbage supplied in my AY-AT kit was putting out close to 6v.
Title: Re: $20 LCR ESR Transistor checker project
Post by: trinhvanthien on May 26, 2019, 05:03:08 am
For the ST7735 you can choose between FONT_10X16_HF, FONT_8X8_HF and FONT_8X16_CYRILLIC_HF (in config_328.h) at the moment. It's also possible to convert some other font. The font file structure is quite simple, but you need to create a few special characters manually (chars 0x01 - 0x07).
Thanks so much for your replay.
Do you have a guide to creating it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 26, 2019, 10:52:22 am
Sorry, I don't have a guide about creating fonts. As a starting point please see bitmaps/font_8x8_hf.h. I think the GLCD Font Creator is able to create the right bitmap format (export as TFT / new GLCD). For linux/unix users I've written a small command line tool to convert bit and byte orders of a character bitmap (hexadecimal input and output).
Title: Re: $20 LCR ESR Transistor checker project
Post by: vivaT on May 29, 2019, 10:29:36 am
Madires I'd like to request including more than one Font and Symbol set or the ability to change the size, if its possible. With this feature a layout using big digits for Resistance, and Inductance along with small text for the other values like esr is possible

Ideally the screen space will be easier to read although I'm not a programmer, but tried to do this myself for the past couple of days with many head scratching moments, but no success.

I'm making a version of the LCR tester in tweezer form just for SMD parts and below is what my 0.96" 128x64 ST7735 screen looks like using the FONT_8x8_HF. Plenty of room for big digits using the Font_12x16_hf




Title: Re: $20 LCR ESR Transistor checker project
Post by: Kenjutsu on May 29, 2019, 01:04:37 pm
I bought the following tester from AliExpress: Mega328 M328 LCR-T4 ESR Meter LCR led Transistor Tester Diode Triode Capacitance MOS PNP/NPN (https://www.aliexpress.com/item/Mega328-M328-LCR-T4-ESR-Meter-LCR-led-Transistor-Tester-Diode-Triode-Capacitance-MOS-PNP-NPN/32849139001.html)

It looks like the same one Dave reviews in EEVblog #1020. My question is if it is worth it to flash the latest firmware, which I assume is in the mega328_MK-328 folder?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 29, 2019, 01:13:41 pm
T4 would be mega328_T3_T4_st7565 or mega328_T4_v2_st7565.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kenjutsu on May 29, 2019, 01:23:21 pm
The listing says: LCR-T3 graphical multi-function tester LCD 12864 LCD display

but this instructable TransistorTester Firmware Flash With Arduino (https://www.instructables.com/id/TransistorTester-Firmware-Flash-With-Arduino/) shows what looks to be the same as mine as a "mega328_GM328"

Is there a way to test which one I have, or should I just flash them until one works?  ;) I will be using a USBAsp
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 29, 2019, 01:44:25 pm
Madires I'd like to request including more than one Font and Symbol set or the ability to change the size, if its possible. With this feature a layout using big digits for Resistance, and Inductance along with small text for the other values like esr is possible

An additional font plus functions for displaying it and managing output would need several kB of flash memory. This would be feasible with an ATmega 644 or 1284. Modifying the current function for displaying characters to allow a double-sized output would increase the code slightly, but the large characters would look crude. And in cases of two resistors or diodes the width of the large font or double sized output could be too large to fit two values into one line. So we would need some control logic for this. I think I'd prefer the first solution (additional font). Is this feature something other users are interested in also?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 29, 2019, 01:58:42 pm
The listing says: LCR-T3 graphical multi-function tester LCD 12864 LCD display

but this instructable TransistorTester Firmware Flash With Arduino (https://www.instructables.com/id/TransistorTester-Firmware-Flash-With-Arduino/) shows what looks to be the same as mine as a "mega328_GM328"

Is there a way to test which one I have, or should I just flash them until one works?  ;) I will be using a USBAsp

That clone looks like a T4. As long as you don't screw up the fuse bits you can test all firmware images if you like. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: vivaT on May 29, 2019, 05:49:03 pm

An additional font plus functions for displaying it and managing output would need several kB of flash memory. This would be feasible with an ATmega 644 or 1284.

I really hope other people will chime in on this topic :)
When the project is finalized it will go up on my github page as I'm sure others will find this a fun project to build.

It's using an ATMega644, building with extended IR protocol and enabled functions like PWM & frequency counter i get the following size result:

AVR Memory Usage
----------------
Device: atmega644

Program:   34152 bytes (52.1% Full)
(.text + .data + .bootloader)
Data:        246 bytes (6.0% Full)
(.data + .bss + .noinit)
EEPROM:      863 bytes (42.1% Full)
(.eeprom)


Is there enough overhead to use a second font?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2019, 09:46:55 am
Yes, 30kB are more than sufficient.
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on May 31, 2019, 12:18:55 pm
Hi, men! :)
I want to offer you the comparative table created by me on the most popular clones.
Look attentively whether I made a mistake or passed some moments?
Sorry, if my English translation is not absolutely good
Hello, indiman.

The comparative table is very interesting and helpful to choose among clones.

I'd suggest adding more info, as the characteristics of the "important" resistors, 2.5V reference and 5V regulator supplied with the kit.

For example, I have the following 3 clones (yes, I suffer from TEA  (https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/) :'() and the characteristics are:
The last one is this one (https://www.banggood.com/DIY-Meter-Tester-Kit-For-Capacitance-ESR-Inductance-Resistor-NPN-PNP-p-929603.html). It also appears in the list in this post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1728737/#msg1728737) by 3roomlab who, apparently, also prepared a list some time ago.

After seeing your table, I've just ordered the Hiland M644 from Aliexpress (https://www.aliexpress.com/item/M644-Multifunctional-Transistor-Tester-LCR-Resistance-Inductance-Diode-Capacitance-ESR-Frequency-Meter-PWM-Signal-Generator/32912063006.html?spm=a2g0s.9042311.0.0.4c684c4dlRjLxf) (yes, my TEA is really bad!). I hope it's really a "hiland" (and not a clone of the clone) because, as you can see in the second one listed above, this manufacturer seems to use better components, and is one of the scarce chinese kit manufacturers that makes some kind of documentation for it's products (https://shop35395693.world.taobao.com/ (https://shop35395693.world.taobao.com/))
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 31, 2019, 02:00:10 pm
Hi morgan_flint!
Thanks for a good review about my work.
Your notes really should be considered in more detail and some things can be added to the table.
But, if with a referensny source everything is rather clear, then on resistors and 5 volt regulator there are questions.
At different forums there were several messages that in the M328Kit set measuring resistors with the admission of 1% instead of 0.1% were enclosed.
Almost the same is observed with the regulator of 5 Volts. Chinese can use in set or ready goods anonymous chips or details with more poor quality. In that case it is possible to deceive future buyer with expectations? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on May 31, 2019, 05:49:39 pm
Of course, you're right, manufacturers can change the quality from one batch to another, so one kit might not be representative, but if some of us posting here can confirm a specific kit has good components, then it can be a clue.

As I said in my previous post, there are also cloners of cloners, which adds difficulty to the problem...

Anyway, it's interesting to know if the tolerances and precision are good because, as stated here in several posts, there are people willing to spend nearly as much as they spent in the kit to upgrade the resistors and regulator/references. Maybe it's better to spend $2-3 more in the kit rather than spending $10 afterward to improve these components
Title: Re: $20 LCR ESR Transistor checker project
Post by: chansw on June 02, 2019, 04:08:50 am
chansw,no, this photo will help you? :)

Hi indman, yes, that photo was very helpful, I was able to successfully upgrade the firmware to 1.13. As it turns out on my BSIDE ESR02 device, the header thru-holes were already present. They are V+, Gnd, Reset, SCLK, MISO, MOSI from top to bottom. In fact, I was able to program the unit without having to solder, I just inserted the header pins and applied moderate side-pressure using an elastic band to ensure a good connection, and wired up my USBASP device accordingly.

In my eagerness I neglected to backup the old 1.11 firmware, do you have a copy of the 1.11 hex and eep that you could send to me? I'd like to have it on-hand if I ever need to deal with a warranty issue.

Thank you, you have been super helpful!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 02, 2019, 11:56:30 am
chansw , backup the old 1.11 firmware see https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1385661/#msg1385661 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1385661/#msg1385661)  :D



The comparative table is very interesting and helpful to choose among clones.

I'd suggest adding more info, as the characteristics of the "important" resistors, 2.5V reference and 5V regulator supplied with the kit.


I updated the comparative table on clones and added information on 5V to the regulator and to referensny source 2.5V. I did not give exact marking of details as the Chinese vendors can use different marking and the name. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: chansw on June 02, 2019, 04:40:25 pm
chansw , backup the old 1.11 firmware see https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1385661/#msg1385661 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1385661/#msg1385661)  :D

Hi indman, I downloaded the firmware that you referenced, it doesn't seem to be the 1.11 that was shipped with the BSIDE ESR02. The original firmware had a startup screen showing the boot image version (1.11) at startup, this one doesn't. I wonder if this was custom or for another device?

If anyone has the BSIDE ESR02 1.11 firmware, could you please post? Thank you.

Jerry
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on June 02, 2019, 06:59:02 pm
Greetings
Question on TС-1, on firmware 1.36m or 1.34m The generator does not work, there is no signal on Pin 2.
At 1.36m config_644.h - changed to PC2 -
/ *
* dedicated signal output via OC1B
* - don't change this!
* /
#define SIGNAL_PORT PORTC / * port data register * /
#define SIGNAL_DDR DDRC / * port data direction register * /
#define SIGNAL_OUT PC2 / * MCU's OC1B pin * /
No signal. What is wrong with the generator? Maybe somewhere that did not finish looking ...?
In TС-1 M644
I used buttons instead of an encoder on PD5, PD7
Which ports are better to connect additional buttons? How in Hiland M644 encoder on PB-5, PB7?
My files: config.h, config_644.h, Makefile...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 02, 2019, 08:10:51 pm
The TC-1 has a poor pin assignment but the ATmega324's PD4 (OC1B) is unused luckily. Changing the settings for the signal output doesn't work because the output is driven by an internal timer which has a fixed output pin (OC1B in this case). Add a resistor to PD4 to limit the current, change the signal port back to PD4, enable HW_FIXED_SIGNAL_OUTPUT in config.c and you'll have a signal output.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on June 03, 2019, 05:00:16 am
Thanks for the quick response! Tell me please, dear madires what port for the frequency meter TC-1, PB0 ? Encoder can be connected to ports on PB-5, PB7?
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 03, 2019, 10:57:53 am
Yes, PB0 (T0) is the input for the frequency counter. The TC-1 doesn't drive the display's /CS, so PB7 (display's SCL) can be used just for the display. With a hardwired /CS anything on SCL will trigger the display to take in data, and a rotary encoder in parallel would screw up SCL. PB5 (display's D/C) and PB6 (display's SDA) could work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on June 03, 2019, 02:58:39 pm
Thank!
Tester TC-1:
Generator output - PD-4 port
Frequency meter input - port PB-0
Encoder or buttons - ports PB-5 and PB-6
Checked, everything works. Firmware for TC-1, in Russian and English.
Sorry, the firmware is only for M644, in my TC-1 - M644 is installed. I turned on almost all features except the IR transmitter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 09, 2019, 12:48:51 pm
Hi,

Where i can download the latest firmware in english for the TC1 ?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 09, 2019, 02:15:35 pm
Do you mean the modified firmware which comes with the TC-1, the k-firmware or the m-firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 09, 2019, 06:47:24 pm
Hello Madires,

My friend has burn is TC1 with a capacitor not discharged. The ATmega328p is dead. I'm looking for a firmware in replacement.
I have found a Markus 1.34 on Yadis. Does it is the lastest or newer is available with Makus or Karl Heinz?

Thanks Madires

Best regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on June 09, 2019, 06:56:29 pm
The TС-1 tester has a M324 or M644 microcontroller, an M328 - I have not met. I made the firmware for M 324 without modifications for quartz 8 and 16 MHz, this is the first digit in the file name. You will need to flash U4, it is described in the subject earlier. I can not check the firmware because I do not have a microcontroller M324.
This is the latest version 1.36M
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 09, 2019, 08:08:43 pm
Hi Andrey,

I don't know the TC1. It's possible to upgrade only the ATmega without to update the U4 ?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on June 10, 2019, 09:20:06 am
Can. But U4 will need to be replaced by the inclusion scheme from the respected madires - « Reply #4843 on: June 13, 2018, 06:14:52 am » https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1604254/#msg1604254   TC1-Mod.pdf
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 10, 2019, 10:51:32 am
Whoever manufactures the TC-1 has made some changes (control MCU U4) which are incompatible with k and m-firmware. For running one of the OSHW firmwares the changes need to be undone. One way is to reprogram U4 (https://github.com/atar-axis/tc1-u4), and the other way is to replace U4 by a small circuit (https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/TC1-Mod.kicad.tgz). The TC-1 also has a few issues with poorly chosen components, especially around the voltage booster for the Zener test. I'd recommend to replace MLCCs C11 and C1 with a 10 or 22µF low-ESR electrolytic rated for 100V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dc8lz on July 04, 2019, 07:34:17 am
Hello!

Poorly I fried up my only some few minutes old ttester.  |O

Can somebody help me with a matching Makefile for the k-trunk (kv. 1.13) or m-firmware? I don't care, it just should work.  :-+

I guess it may be close to the mega328_GM328 or mega328_color_kit?

It was sold on ebay as "TFT GM328 Transistor Tester Diode LCR ESR meter PWM Square wave Voltmeter W0", see https://www.ebay.de/itm/273874481843 (https://www.ebay.de/itm/273874481843)

During repairing the tester I will switch to 16MHz, crystal already changed.

By the way I am very interested in measuring low inductivities with the sampling method.

Thanks all for help,
beste regards Stephan
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on July 04, 2019, 08:41:19 am
Hallo Stephan,

take the 'mega328_color_kit', the 'M-Software' looks littlebit better at the color display, but have no support for the sampling method.

best regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: dc8lz on July 04, 2019, 06:55:17 pm
Hello Horst,

Hallo Stephan,

take the 'mega328_color_kit', the 'M-Software' looks littlebit better at the color display, but have no support for the sampling method.

best regards Horst

Thank you for your help. Ok, I will check the k-firmware mega328_color_kit.

With my first test and the hex end eprom files from svn I get a all-pixle-white screen after pressing one time the rotary button. I hope I did not damage the display or another part.

Btw... if somebody has the original files or a surely working Makefile... let me know, thanks!

Best regards, Stephan
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on July 04, 2019, 07:17:54 pm
I bought one of the newer Hiland testers from eBay https://www.ebay.com/itm/132987823813 (https://www.ebay.com/itm/132987823813) for $20.

It looks nicely made and the components are reasonable quality.  IC1 is a 1117M3 and it has an ATMEGA64 processor and an 8 MHz Xtal.  I've attached a photo for y'all.

Are there any recommended hardware updates for this one?  Also, it says "Hiland Elec" with a URL at the bottom of the screen on startup.  Can I program this with a better firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 04, 2019, 08:58:37 pm
That tester has the extended frequency counter and possibly the Zener check. Both OSHW firmwares (k & m) should run fine. Changing the quartz crystal to a 16MHz type would increase the frequency limits for signal output and frequency counter while also improving some measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on July 04, 2019, 09:32:36 pm
Hi Stephan,

if you switch the tester on, go the control LED on and after release the switch, is the LED still on? If it is so, insert a LED in the testconnector. At the next switch on, the inserted LED will blink sometimes?

regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: dc8lz on July 04, 2019, 10:00:58 pm
Hello!

Hi Stephan,

if you switch the tester on, go the control LED on and after release the switch, is the LED still on? If it is so, insert a LED in the testconnector. At the next switch on, the inserted LED will blink sometimes?

regards Horst

Yes, the LED blinks sometimes. But all the time LED backlight/white display is on. I guess my display is broken, too. :-(

If I am right this one has a kind of level shifter so that it work with the 5V of the atmega. Would like to buy a new display but until now I only find cheaper ones with 3V... hm... sad.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on July 04, 2019, 10:21:54 pm
Hello Stephan,

test the signal-pins at the display with your oszilloscope for plausible pegel at the right pins and also the LDO output must have 3.3 VDC.

Regards Horst

P.S. im Anhang die pin- und signalbelegung
Title: Re: $20 LCR ESR Transistor checker project
Post by: dc8lz on July 05, 2019, 08:42:53 am
Tnx Horst!

Signal looks good so far. I will buy another display. Will take some time.. :-/

But thanks a lot, the display pinout is very helpfully.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on July 05, 2019, 10:07:16 am
That tester has the extended frequency counter and possibly the Zener check. Both OSHW firmwares (k & m) should run fine. Changing the quartz crystal to a 16MHz type would increase the frequency limits for signal output and frequency counter while also improving some measurements.
Thanks.  What's the IDE that the code I downloaded from Github compiles in? 

Not thread-specific but does anyone know why my photos (taken on my iPhone 7+) all seem to be upside down?  Is it because the eevblog server is in Australia where up is down?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on July 05, 2019, 10:34:07 am
Hello Stephan,

i send a PN to you.

regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 05, 2019, 03:49:12 pm
What's the IDE that the code I downloaded from Github compiles in? 

Nothing special, just avr-gcc and make (and avrdude for ISP).

Not thread-specific but does anyone know why my photos (taken on my iPhone 7+) all seem to be upside down?  Is it because the eevblog server is in Australia where up is down?

The server is located in the USA. Maybe your phone is re-imported from down under? ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 06, 2019, 10:43:45 am
That tester has the extended frequency counter and possibly the Zener check. Both OSHW firmwares (k & m) should run fine. Changing the quartz crystal to a 16MHz type would increase the frequency limits for signal output and frequency counter while also improving some measurements.
I had not realized it could check Zener diodes, a quick check on the original eBay auction confirms it but it was not clear about how.
You place the diode on the Vext+ pin and ground, with the stripe against the positive pin.
Next you go into the menu and select "Voltage" after that 0mv will be shown on the screen.
Now you hold the test button down: 44v is generated on the Vext+ pin and the drop on your zener will be shown on the screen.
In this case it was a 20v Zener...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on July 06, 2019, 12:59:33 pm
So, apparently the way to make iPhone pictures come out the right way up here is to a) Use a Mac computer b) Make sure the volume buttons are facing downwards when taking the picture.  A fuller explanation is here (https://iphonephotographyschool.com/iphone-photos-upside-down/).

My process steps are to email the pictures to myself and then save them to my Windows PC and then choose them for upload to the forum.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TechieTX on July 06, 2019, 09:37:34 pm
Hello!

Poorly I fried up my only some few minutes old ttester.  |O

Can somebody help me with a matching Makefile for the k-trunk (kv. 1.13) or m-firmware? I don't care, it just should work.  :-+

I guess it may be close to the mega328_GM328 or mega328_color_kit?

It was sold on ebay as "TFT GM328 Transistor Tester Diode LCR ESR meter PWM Square wave Voltmeter W0"

During repairing the tester I will switch to 16MHz, crystal already changed.

By the way I am very interested in measuring low inductivities with the sampling method.

Thanks all for help,
beste regards Stephan

Howdy, Stephan!

I just finished compiling the latest 1.36m for my AY-AT board (looks the same as yours other than the silkscreen).  I run an ATMega328, not the -328P so my Makefile is modified for that part.  I also have 16MHz xtal, and I'm using a USBasp for a programmer.  If you use the current 1.36m release from https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware and drop these files in place (preferably saving off the original config.h, config_328.h and Makefile in a sub-folder for comparison) then it should compile and work for you.  You might need to change the actual MCU in line 58 of the Makefile to 'm328p', and of course your programmer string may well be different, so you'll need to modify that in the Makefile as well.  I have the ST7735 display and can't tell from your photo if that's what you have there.

I did a couple of small tweaks to the conf files to match my hardware, but it should still boot and run reasonably well for you.  I have the precision 5V regulator and 0.1% resistors.

edit: I added pix of the diffs between Madires' original (left) and my modifications (right) in case you need to see what changed
Title: Re: $20 LCR ESR Transistor checker project
Post by: jshonw on July 08, 2019, 09:34:06 am
Madires, can you tell me how the capacitor tables in variables.h were derived?  I am thinking of using slightly different values for the 680 and 470k resistors and it seems to me that I will need to recalculate those tables.  I tried looking at the source code for the SmallCap function and couldn't figure what the table values represent.   


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 08, 2019, 10:22:59 am
Please see the comment above LargeCap(). It explains the equation and also shows how to calculate the table values with bc (unix command line calculator).
Title: Re: $20 LCR ESR Transistor checker project
Post by: jshonw on July 08, 2019, 07:17:23 pm
Madires, Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: can on July 10, 2019, 12:21:43 pm
hello friends I want to do from this test device I have a st7735spi lcd screen and I want to use atmega328p as the processor I have a lot of information on the pages, but I do not get a kind of image on the screen to compile the main files of the software which are using the program I am waiting for your help. thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: can on July 10, 2019, 12:24:47 pm
(http://)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 10, 2019, 01:35:43 pm
hello friends I want to do from this test device I have a st7735spi lcd screen and I want to use atmega328p as the processor I have a lot of information on the pages, but I do not get a kind of image on the screen to compile the main files of the software which are using the program I am waiting for your help. thanks

k or m-firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: can on July 10, 2019, 02:34:21 pm
I did not understand
Title: Re: $20 LCR ESR Transistor checker project
Post by: can on July 11, 2019, 08:03:23 am
hello friends GM328A model I want to make the test device, but I just install the hex file to the processor program is running, some information comes to the screen, but when I install the eeprom file does not show any text on the screen can you help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 11, 2019, 09:08:52 am
How exactly are you programming the flash and the EEPROM?
Title: Re: $20 LCR ESR Transistor checker project
Post by: can on July 11, 2019, 12:01:16 pm
fuse settings I've set up this way il load flash file and then I install eeprom file
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 11, 2019, 01:15:04 pm
Don't you use a quartz crystal (lfuse setting 0xf7)? Everything else seems to be fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TechieTX on July 11, 2019, 10:34:01 pm
I've never seen that file version, but the fuses are all wrong in any case.  Try this instead:

(https://i.imgur.com/niXlaZC.jpg)

It's not verifying, so the processor is off in the weeds after writing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: towe96 on July 12, 2019, 10:59:48 am
I have an AY-AT clone with the v1.36m firmware.

How would I go about testing reverse hFE of components like a PNP transistor? Simply inserting it the other way around only changes the reading between EBC and CBE types.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 12, 2019, 01:31:28 pm
Sorry, neither k nor m-firmware display the reverse hFE, but it's measured during the BJT detection. I'll put that feature on my to-do list.
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on July 17, 2019, 07:45:09 am
Hi,
i have etched the PCB as provided on the github by Max
but there is transistor Q1 and its collecter is left out, what is the purpose of it or is it a mistake ?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 17, 2019, 09:24:43 am
I think it's the lack of the correct symbol. That should be the external 2.5V reference (LM4040, TL431).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Roman81 on July 19, 2019, 03:49:36 pm
Hello I'm new here and to electronics. Got interested a few year ago and started learning bit by bit (mostly from youtube) so my knowledge is very limited.
Bought the tester on Aliexpress but didn't notice it was the kit and not assembled 1, in the pics it was all assembled with the case and I didn't read the small print well enough but that's on me. Got it a few days ago and today finally got to assembling it. All went well it turned on no prob but when I tried to calibrate it it did resistance ok but when it came to capacitance testing it showed 6 - 6 - 44 as reference test and after it showed all the capacitores wrong showing way less.
Here is a vid of me trying to calibrate  https://www.youtube.com/watch?v=v2p95KzWlqk&t=31s (https://www.youtube.com/watch?v=v2p95KzWlqk&t=31s)
Measured the 470k resistors and the middle 1 shows 445k in circuit and 469.6 out.
Is the volt ref here is 5V? It showed 5.002V on the LT1004 pins. When i try to measure voltage with the board it shows around 200mV higher than it is.
It doesn't see any resistors that i try to test.
It shows transistor info.
Few pics showing the assembled module, would love to hear any criticism or suggestions. Please help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 19, 2019, 06:16:33 pm
The external voltage reference should be a 2.5V type. Some users have reported issues with IC4 (SRV5-04). It's meant for input protection and can be removed (tester will work without it).

PS: Welcome to the forum! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on July 23, 2019, 05:59:20 pm
Hallo Madires,

i have a problem with the Hiland 644M Clone and the M-SW 1.36 and 1.35 also. In the mikrocontroller.net i have a sheet with the div. measurements.

Sorry, my english is not good enough to discuss it here.

Best regards

Horst

P.S.: at the attachment the picture shows as the left one the Hiland 644M with the "wrong" data. The table as PDF shows the measurements of the test with div. testers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 24, 2019, 08:29:31 am
Obelix2007 has reported that his Hiland 644M shows wrong hFE values (too high) when running the m-firmware. On a tester with  ATmega328 everything is fine. And running the k-firmware on the Hiland 644M the hFE values are fine too. I've done a quick check of several NPNs with a 328 tester and a 644 and the hFE values match closely. At the moment I don't have any idea what could cause that issue. If you have a Hiland 644M and a different tester (or run both firmwares on the Hiland) please check a few BJTs and let me know the hFE values.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on July 29, 2019, 02:44:34 am
...  Can I program this with a better firmware?

Hi Gandalf,

did you test your Hiland644M with the m-firmware 1.36?

I have some problems with the hFE measurement?
Can you test some BJTs to compare the readings?
Sorry my bad english.

Best regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 30, 2019, 08:15:01 am
That tester has the extended frequency counter and possibly the Zener check. Both OSHW firmwares (k & m) should run fine. Changing the quartz crystal to a 16MHz type would increase the frequency limits for signal output and frequency counter while also improving some measurements.
I had not realized it could check Zener diodes, a quick check on the original eBay auction confirms it but it was not clear about how.
You place the diode on the Vext+ pin and ground, with the stripe against the positive pin.
Next you go into the menu and select "Voltage" after that 0mv will be shown on the screen.
Now you hold the test button down: 44v is generated on the Vext+ pin and the drop on your zener will be shown on the screen.
In this case it was a 20v Zener...
Turns out the Zener diode test is not so useful after all.
I bought a Zener diode assortment kit when I needed specifically a 5.1v Zener for a project.
Thinking I'd sort out the one with the best value.
The tester gave values of 4.80v for most of them, and then finally the last two showed up as 5.0 and 5.1v.
However on my bench supply with a 0.01A load they all where in the range of 5.12 to 5.23v.
So meh...
Maybe it could be fixed by replacing the resistor used for the voltage test though, so it outputs higher current?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 30, 2019, 08:53:15 am
Per Hansson It is possible to make the choice of value of current (1 mA, 5 mA, 10 mA) given through Zener and to collect the simple scheme with the current regulator. An example on a photo. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 30, 2019, 08:59:16 am
Yep, the test current matters for a Zener because it needs a minimum current to be stable. To modify the test current please have a look at the circuit around T5 (current limiter). Try a lower value for R32. The 644 circuit in Karl-Heinz' excellent documentation uses a similar current limiter with a jumper to select 1 or 5mA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: electron1979 on July 30, 2019, 10:12:44 am
Hey all,
I'm looking to purchase one of the testers, but not sure which one I should get.
I'm thinking of the following 3, but if you want to suggest a different one, feel free.
It doesn't need to be portable/rechargable.
Should I care about the Chinese FW or focus on the 1.13k or 1.35m FW?
I think I would prefer the "k-firmware" as it "supports the SamplingADC for measuring low value caps and coils", https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg2400432/#msg2400432
I have read that the 16MHz units could provide better accuracy?
As the features of the LCR-TC1 (AU$18.90) and LCR-T7 (AU$28.89) look the same, AFAIK, I should probably get the LCR-TC1?
If you guys were buying one, what would you buy, taking into account my requirements?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 30, 2019, 11:16:11 am
LCR-TC1 and LCR-T7 have an additional small MCU to control power and test button. If you want to run k or m-firmware you need to reprogram the control MCU (https://github.com/atar-axis/tc1-u4) or to replace it with a small circuit (TC1-Mod in the repo). They do also have a few hardware issues (see m-firmware's Clones file). Maybe an AY-AT clone or a Hiland 644?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on August 02, 2019, 06:27:27 am
LCR-TC1 and LCR-T7 have an additional small MCU to control power and test button. If you want to run k or m-firmware you need to reprogram the control MCU (https://github.com/atar-axis/tc1-u4) or to replace it with a small circuit (TC1-Mod in the repo). They do also have a few hardware issues (see m-firmware's Clones file). Maybe an AY-AT clone or a Hiland 644?
I made this HW modifications and also flashed the u4.

But how to get main firmware for atmega? Is it necessary to compile the firmware by myself or is there any hex file for download? If I has to compile it: How can I do it? SW isn't my skill.

BTW: My TC-1 was delvivered with 644, maybe you will add it to your "clones" file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 02, 2019, 12:05:39 pm
Yes, the firmware has to be compiled for the TC1 (k and m-firmware). There are a few posts in this thread on how to compile it. Nothing special, just the common way for AVRs. And configuring the firmware for the tester is described in the documentation. Thanks for the hint on the new TC1 model with an ATmega644.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on August 02, 2019, 01:41:00 pm
Per Hansson It is possible to make the choice of value of current (1 mA, 5 mA, 10 mA) given through Zener and to collect the simple scheme with the current regulator. An example on a photo. :)
Yep, the test current matters for a Zener because it needs a minimum current to be stable. To modify the test current please have a look at the circuit around T5 (current limiter). Try a lower value for R32. The 644 circuit in Karl-Heinz' excellent documentation uses a similar current limiter with a jumper to select 1 or 5mA.
Excellent, thanks for the spot on advice.
The original R32 resistor has SMD marking 01B so 1kΩ and the produced current was 1.3mA
I paralleled a 150Ω resistor with it and now I get 12mA test current.
And the 5v Zeners read much closer to what my bench supply does with the same settings.
That said I guess 10mA can be too much for higher voltage Zeners, lets say generally above 30v.
However since the tester can only generate 45v anyway I think it's a decent compromise.
Of course the use of a jumper or switch to select would be better, but would also take more than 5 seconds to implement ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on August 02, 2019, 06:16:50 pm

Hi Gandalf,

did you test your Hiland644M with the m-firmware 1.36?

I have some problems with the hFE measurement?
Can you test some BJTs to compare the readings?
Sorry my bad english.


Hi Per Hansson,

... the same question as above to You?

Best regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on August 03, 2019, 11:09:03 am
I'm still running the original Chinese firmware on it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on August 03, 2019, 06:48:46 pm
Been gone for quite some time (surgery, meds, et al) and thought I would share this video I just watched.

It is about a 328p clone from Logic Green. 32Mhz, 12 bit ADC and differential, a DAC, three selectable Vref (1,024, 2.048, 4.096), six pins that can handle 80 mA, and is 99% UNO/Nano compatible. The Micro Pro version is 79 cents US. It also works down to 1.8v @ 32MHz

https://www.youtube.com/watch?v=Myfeqrl3QP0 (https://www.youtube.com/watch?v=Myfeqrl3QP0)

Not sure how to embed a video.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 04, 2019, 02:39:10 am
What a coincidence. I watched that video, too, and it made me think of this project. With a firmware update, the QFP version could be a drop-in replacement on those boards that use that form factor IC.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 04, 2019, 12:30:15 pm
The LGT8F328P is an interesting 328 clone. It has also more I/O pins, i.e. four power pins are replaced with port pins (PE). I wonder if the 12 bit ADC provides a real benefit over the 328's 10 bit (they dropped AVCC). Could be an inexpensive alternative but not using the additional I/O pins seems to be a waste. On the other side, 32kB flash aren't enough for all the possible tester options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 05, 2019, 07:04:31 pm
If the 328 clone sells well, maybe they'll make a 2560 clone. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on August 12, 2019, 02:29:25 pm
Hi
I have this LCR-T4 which i bricked previously by messing with fuse bits and installing latest software
here is the link to post: https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1860888/#msg1860888

since i dont have high voltage programmer to reset the chip, so i bought another chip
but this one is updated one i.e. m328pb
installed the chip on the board and flashed this firmware https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_T4_v2_st7565 (https://github.com/svn2github/transistortester/tree/master/Software/trunk/mega328_T4_v2_st7565)
but i only get backlight and no display
since i dont want to mess with fuse bit on my own so am aking here, what will be the proper fuse settings  for Atmega 328pb version ?

here is the flash log

Code: [Select]
avrdude -c avrisp -b 19200 -p m328pb -P COM7 -U flash:w:TransistorTester.hex:a -U eeprom:w:TransistorTester.eep:a -v

avrdude: Version 6.3-20171130
         Copyright (c) 2000-2005 Brian Dean, [url]http://www.bdmicro.com/[/url]
         Copyright (c) 2007-2014 Joerg Wunsch

         System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf"

         Using Port                    : COM7
         Using Programmer              : avrisp
         Overriding Baud Rate          : 19200
         AVR Part                      : ATmega328PB
         Chip Erase delay              : 9000 us
         PAGEL                         : PD7
         BS2                           : PC2
         RESET disposition             : dedicated
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
           flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
           lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
           signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

         Programmer Type : STK500
         Description     : Atmel AVR ISP
         Hardware Version: 2
         Firmware Version: 1.18
         Topcard         : Unknown
         Vtarget         : 0.0 V
         Varef           : 0.0 V
         Oscillator      : Off
         SCK period      : 0.1 us

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.05s

avrdude: Device signature = 0x1e9516 (probably m328pb)
avrdude: safemode: lfuse reads as FF
avrdude: safemode: hfuse reads as DA
avrdude: safemode: efuse reads as FD
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
         To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: reading input file "TransistorTester.hex"
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: writing flash (29732 bytes):

Writing | ################################################## | 100% 33.26s

avrdude: 29732 bytes of flash written
avrdude: verifying flash memory against TransistorTester.hex:
avrdude: load data flash data from input file TransistorTester.hex:
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: input file TransistorTester.hex contains 29732 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 18.99s

avrdude: verifying ...
avrdude: 29732 bytes of flash verified
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (857 bytes):

Writing | ################################################## | 100% 42.28s

avrdude: 857 bytes of eeprom written
avrdude: verifying eeprom memory against TransistorTester.eep:
avrdude: load data eeprom data from input file TransistorTester.eep:
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: input file TransistorTester.eep contains 857 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 3.46s

avrdude: verifying ...
avrdude: 857 bytes of eeprom verified

avrdude: safemode: lfuse reads as FF
avrdude: safemode: hfuse reads as DA
avrdude: safemode: efuse reads as FD
avrdude: safemode: Fuses OK (E:FD, H:DA, L:FF)

avrdude done.  Thank you.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 12, 2019, 04:58:22 pm
The only difference is the CFD (disable counter failure detection) bit in the e-fuse, i.e. F4 instead of FC.
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on August 12, 2019, 07:17:01 pm
The only difference is the CFD (disable counter failure detection) bit in the e-fuse, i.e. F4 instead of FC.

thanks for the fuse settings, have updated fuses and the chip is not bricked as yet :)
but have the same problem, after flashing the firmware and eep file, it turns only backlight on and no display. Is this another variant ?


uploading old pics when it had working chip
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on August 12, 2019, 08:07:49 pm
The pinout of the PB version is different:

https://forum.mysensors.org/topic/3969/upgrade-to-atmega328pb (https://forum.mysensors.org/topic/3969/upgrade-to-atmega328pb)

https://www.microchip.com/wwwAppNotes/AppNotes.aspx?appnote=en591418 (https://www.microchip.com/wwwAppNotes/AppNotes.aspx?appnote=en591418)
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on August 13, 2019, 07:03:33 am
Does BSIDE tester has any benefits vs MK-328 model?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 13, 2019, 02:42:23 pm
The pinout of the PB version is different:

Slightly, but PE (especially PE0 and PE1) should be in HiZ mode by default. Or try to lift the two pins.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 13, 2019, 03:29:50 pm
thanks for the fuse settings, have updated fuses and the chip is not bricked as yet :)
but have the same problem, after flashing the firmware and eep file, it turns only backlight on and no display. Is this another variant ?

Does the oscillator run?
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on August 13, 2019, 03:31:51 pm
Does the oscillator run?

will try lifting the pins later today. 
I dont know how to check if oscillator is running ?
but i am able to program the chip from ISP programmer

edit:
i have pulled the chip from arduino nano, have checked on that board, pin 3 is connected to gnd and pin 6 to vccc (5v) as usual and no changes were made on that board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: macinblack on August 14, 2019, 01:43:29 pm
Hello everyone, can someone share the lastest firmware (hex) and EEPROM 1.36m compiled of this transistor test? I tried to upload with avrdudess the gm328 color kit firmware of atmega328p but without success...
 (https://images-na.ssl-images-amazon.com/images/I/717F5JENqUL._SX466_.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 14, 2019, 02:38:45 pm
Does the oscillator run?

will try lifting the pins later today. 
I dont know how to check if oscillator is running ?
but i am able to program the chip from ISP programmer

If you're able to program the ATmega via ISP then the oscillator is running.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 14, 2019, 02:43:50 pm
Hello everyone, can someone share the lastest firmware (hex) and EEPROM 1.36m compiled of this transistor test? I tried to upload with avrdudess the gm328 color kit firmware of atmega328p but without success...

Your tester is an AY-AT clone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: macinblack on August 14, 2019, 06:38:28 pm
Bu can I upload the firmware 1.36m? or just the original 1.12k? In this moment it's totally useless without any of both.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 14, 2019, 06:54:31 pm
If you like to run the k-firmware please try mega328_color_kit. For the m-firmware you need to compile it yourself (settings for the AY-AT clone are explained in the Clones file).
Title: Re: $20 LCR ESR Transistor checker project
Post by: towe96 on August 15, 2019, 02:30:43 pm
I have the exact same device and flashed 1.36m the day it came out - works well so far.

Please see the attached files.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mastermind on August 16, 2019, 09:11:39 am
hi
i have lcr-t4 and update firmware and device not turn on .lcd blank and back-light dont turn on.the avrdude now cannot found device with this message
  avrdude.exe: warning: cannot set sck period. please check for usbasp firmware update.
avrdude.exe: error: program enable: target doesn't answer. 1
avrdude.exe: initialization failed, rc=-1
             Double check connections and try again, or use -F to override
             this check.

whats problem??my device is new
tnx
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 16, 2019, 10:24:05 am
Does the backlight stay on as long as you press the test button? Or does it stay off even when pressing the button?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mastermind on August 16, 2019, 01:20:51 pm
Does the backlight stay on as long as you press the test button? Or does it stay off even when pressing the button?
no,the backlight doesn't turn on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 16, 2019, 04:11:05 pm
Which firmware have you programmed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mastermind on August 16, 2019, 04:18:40 pm
Which firmware have you programmed?
LCR-Tx_v1.12k_r453_EN file eep and hex .how can i check if avr broken or other part?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 16, 2019, 05:10:57 pm
Do you have the new version of the T4 (v2)? Please try mega328_T4_v2_st7565.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mastermind on August 16, 2019, 05:28:34 pm
Do you have the new version of the T4 (v2)? Please try mega328_T4_v2_st7565.
my problem now is the avr programmer do not recognize device to reprogram it again   
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 16, 2019, 06:08:37 pm
Have you changed any fuse bits?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mastermind on August 16, 2019, 06:20:15 pm
Have you changed any fuse bits?
yes
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 16, 2019, 07:04:26 pm
And which ones?
Title: Re: $20 LCR ESR Transistor checker project
Post by: mastermind on August 17, 2019, 06:10:04 am
And which ones?
tnx for your help, unfortunately i dont remember
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on August 17, 2019, 02:59:30 pm
Slightly, but PE (especially PE0 and PE1) should be in HiZ mode by default. Or try to lift the two pins.

Lifting pin 3 & 6 did the trick,
its running now but its dead slow, the initial setup is running but it stuck on capacitor test.

its dead slow

below is flash log with fuses
Code: [Select]
avrdude -c avrisp -b 19200 -p m328pb -P COM7 -U flash:w:TransistorTester.hex:a -U eeprom:w:TransistorTester.eep:a -v

avrdude: Version 6.3-20171130
         Copyright (c) 2000-2005 Brian Dean, [url]http://www.bdmicro.com/[/url]
         Copyright (c) 2007-2014 Joerg Wunsch

         System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf"

         Using Port                    : COM7
         Using Programmer              : avrisp
         Overriding Baud Rate          : 19200
         AVR Part                      : ATmega328PB
         Chip Erase delay              : 9000 us
         PAGEL                         : PD7
         BS2                           : PC2
         RESET disposition             : dedicated
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
           flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
           lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
           signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

         Programmer Type : STK500
         Description     : Atmel AVR ISP
         Hardware Version: 2
         Firmware Version: 1.18
         Topcard         : Unknown
         Vtarget         : 0.0 V
         Varef           : 0.0 V
         Oscillator      : Off
         SCK period      : 0.1 us

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.05s

avrdude: Device signature = 0x1e9516 (probably m328pb)
avrdude: safemode: lfuse reads as F7
avrdude: safemode: hfuse reads as D9
avrdude: safemode: efuse reads as F4
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
         To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: reading input file "TransistorTester.hex"
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: writing flash (29732 bytes):

Writing | ################################################## | 100% 33.39s

avrdude: 29732 bytes of flash written
avrdude: verifying flash memory against TransistorTester.hex:
avrdude: load data flash data from input file TransistorTester.hex:
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: input file TransistorTester.hex contains 29732 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 19.04s

avrdude: verifying ...
avrdude: 29732 bytes of flash verified
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (857 bytes):

Writing | ################################################## | 100% 42.34s

avrdude: 857 bytes of eeprom written
avrdude: verifying eeprom memory against TransistorTester.eep:
avrdude: load data eeprom data from input file TransistorTester.eep:
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: input file TransistorTester.eep contains 857 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 3.57s

avrdude: verifying ...
avrdude: 857 bytes of eeprom verified

avrdude: safemode: lfuse reads as F7
avrdude: safemode: hfuse reads as D9
avrdude: safemode: efuse reads as F4
avrdude: safemode: Fuses OK (E:F4, H:D9, L:F7)

avrdude done.  Thank you.



its on default 8mhz crystal and running this firmware
https://github.com/svn2github/transistortester/blob/master/Software/trunk/mega328_T4_v2_st7565/ (https://github.com/svn2github/transistortester/blob/master/Software/trunk/mega328_T4_v2_st7565/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 17, 2019, 03:48:44 pm
I've checked the clock settings for the 328PB and it doesn't have the full swing crystal option anymore. So you have to set the clock source to low power crystal, i.e. l-fuse should be ff.
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on August 17, 2019, 05:08:49 pm
I've checked the clock settings for the 328PB and it doesn't have the full swing crystal option anymore. So you have to set the clock source to low power crystal, i.e. l-fuse should be ff.

changed the fuse settings, but no change, should i reflash the firmware ?

Code: [Select]
avrdude -c avrisp -b 19200 -p m328pb -P COM7 -U efuse:w:0xF4:m -U hfuse:w:0xD9:m -U lfuse:w:0xFF:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.05s

avrdude: Device signature = 0x1e9516 (probably m328pb)
avrdude: reading input file "0xF4"
avrdude: writing efuse (1 bytes):

Writing | ################################################## | 100% 0.02s

avrdude: 1 bytes of efuse written
avrdude: verifying efuse memory against 0xF4:
avrdude: load data efuse data from input file 0xF4:
avrdude: input file 0xF4 contains 1 bytes
avrdude: reading on-chip efuse data:

Reading | ################################################## | 100% 0.01s

avrdude: verifying ...
avrdude: 1 bytes of efuse verified
avrdude: reading input file "0xD9"
avrdude: writing hfuse (1 bytes):

Writing | ################################################## | 100% 0.02s

avrdude: 1 bytes of hfuse written
avrdude: verifying hfuse memory against 0xD9:
avrdude: load data hfuse data from input file 0xD9:
avrdude: input file 0xD9 contains 1 bytes
avrdude: reading on-chip hfuse data:

Reading | ################################################## | 100% 0.02s

avrdude: verifying ...
avrdude: 1 bytes of hfuse verified
avrdude: reading input file "0xFF"
avrdude: writing lfuse (1 bytes):

Writing | ################################################## | 100% 0.03s

avrdude: 1 bytes of lfuse written
avrdude: verifying lfuse memory against 0xFF:
avrdude: load data lfuse data from input file 0xFF:
avrdude: input file 0xFF contains 1 bytes
avrdude: reading on-chip lfuse data:

Reading | ################################################## | 100% 0.02s

avrdude: verifying ...
avrdude: 1 bytes of lfuse verified

avrdude: safemode: Fuses OK (E:F4, H:D9, L:FF)

avrdude done.  Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 17, 2019, 06:04:18 pm
No need to program the same firmware again. Usually the main cause for a slow tester is the CKDIV8 bit. When set the clock is divided by 8, but with l-fuse set to ff CKDIV8 is disabled. You could try to switch the clock source to the internal RC oscillator by setting l-fuse to e2 (just for testing if there's a problem with the crystal oscillator).
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on August 17, 2019, 06:14:55 pm
No change, still dead slow

Code: [Select]
avrdude -c avrisp -b 19200 -p m328pb -P COM7 -U flash:w:TransistorTester.hex:a -U eeprom:w:TransistorTester.eep:a -v

avrdude: Version 6.3-20171130
         Copyright (c) 2000-2005 Brian Dean, [url]http://www.bdmicro.com/[/url]
         Copyright (c) 2007-2014 Joerg Wunsch

         System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr\bin\avrdude.conf"

         Using Port                    : COM7
         Using Programmer              : avrisp
         Overriding Baud Rate          : 19200
         AVR Part                      : ATmega328PB
         Chip Erase delay              : 9000 us
         PAGEL                         : PD7
         BS2                           : PC2
         RESET disposition             : dedicated
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
           flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
           lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
           signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

         Programmer Type : STK500
         Description     : Atmel AVR ISP
         Hardware Version: 2
         Firmware Version: 1.18
         Topcard         : Unknown
         Vtarget         : 0.0 V
         Varef           : 0.0 V
         Oscillator      : Off
         SCK period      : 0.1 us

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.05s

avrdude: Device signature = 0x1e9516 (probably m328pb)
avrdude: safemode: lfuse reads as E2
avrdude: safemode: hfuse reads as D9
avrdude: safemode: efuse reads as F4
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
         To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: reading input file "TransistorTester.hex"
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: writing flash (29732 bytes):

Writing | ################################################## | 100% 33.30s

avrdude: 29732 bytes of flash written
avrdude: verifying flash memory against TransistorTester.hex:
avrdude: load data flash data from input file TransistorTester.hex:
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: input file TransistorTester.hex contains 29732 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 19.14s

avrdude: verifying ...
avrdude: 29732 bytes of flash verified
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (857 bytes):

Writing | ################################################## | 100% 42.31s

avrdude: 857 bytes of eeprom written
avrdude: verifying eeprom memory against TransistorTester.eep:
avrdude: load data eeprom data from input file TransistorTester.eep:
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: input file TransistorTester.eep contains 857 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 3.46s

avrdude: verifying ...
avrdude: 857 bytes of eeprom verified

avrdude: safemode: lfuse reads as E2
avrdude: safemode: hfuse reads as D9
avrdude: safemode: efuse reads as F4
avrdude: safemode: Fuses OK (E:F4, H:D9, L:E2)

avrdude done.  Thank you.


will try to install another crystal tomorow,
could it be a bad chip ?
or the firmware is not for 8mhz ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 17, 2019, 07:41:52 pm
Since the internal RC oscillator doesn't resolve the issue the crystal should be fine. And the firmware is compiled for 8 MHz. CFD (Clock Failure Detection) switches the clock to 1MHz (internal RC plus divider) in case of a problem with the external clock or crystal, but CFD is disabled (e-fuse f4). Still, there's something wrong with the clock or clock prescaler.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on August 18, 2019, 04:23:55 pm
It is so old tread  :)

Great works and projects. And I see bunch of forks  :-+

But how I can start TT in 2019?

What fork is actual/progressive/usable now?

I`m gonna build TT with Arduino nano (https://www.ebay.com/itm/3pcs-x-Nano-V3-module-ATMega328-P-CH340G-16MHz-mini-USB-compatible-Arduino-D7-SF/323414472916?epid=11022866083&hash=item4b4d0138d4:g:neoAAOSw5sBbgfy8 (https://www.ebay.com/itm/3pcs-x-Nano-V3-module-ATMega328-P-CH340G-16MHz-mini-USB-compatible-Arduino-D7-SF/323414472916?epid=11022866083&hash=item4b4d0138d4:g:neoAAOSw5sBbgfy8)) and 2.9" 128*64 display since my eyes really needs LARGE pic (https://www.ebay.com/itm/128x64-LCD-Module-Display-LCM-ST7920-Controller-Paraller-Serial-white-on-Black/291836077918?hash=item43f2c9275e:g:sm0AAOSwj2Za1uv6 (https://www.ebay.com/itm/128x64-LCD-Module-Display-LCM-ST7920-Controller-Paraller-Serial-white-on-Black/291836077918?hash=item43f2c9275e:g:sm0AAOSwj2Za1uv6))
Is it good way?

Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on August 18, 2019, 06:08:30 pm
...I see bunch of forks  :-+
But how I can start TT in 2019?
What fork is actual/progressive/usable now?
You can start by reading the docs:
1. https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/
2. 'Readme' and 'changes.txt' files inside the 'ComponentTester-1.36m.tgz' from
   https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on August 18, 2019, 06:54:54 pm
...I see bunch of forks  :-+
But how I can start TT in 2019?
What fork is actual/progressive/usable now?
You can start by reading the docs:
1. https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/
2. 'Readme' and 'changes.txt' files inside the 'ComponentTester-1.36m.tgz' from
   https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware


Thanx!  :-+
Is hardware still same?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on August 19, 2019, 12:59:05 am
Is hardware still same?
Docs will answer almost all the questions. But yes, the circuit is still the same, the one in the .pdf document.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on August 19, 2019, 07:18:49 am
Is hardware still same?
Docs will answer almost all the questions. But yes, the circuit is still the same, the one in the .pdf document.

Thanx

But I have stupid question
How to program 16MHz (Arduino) instead 8Mhz quarz?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on August 19, 2019, 06:55:16 pm
But I have stupid question
How to program 16MHz (Arduino) instead 8Mhz quarz?
Search '16MHz' in this thread.

Also (with a translator): https://www.mikrocontroller.net/topic/248078 (https://www.mikrocontroller.net/topic/248078)
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirAlucard on August 21, 2019, 08:56:45 pm
So after reading through lots of posts and trying to figure out how to go about updating the firmware on the Transistor Checker that I have, I finally gave in and figured I'd ask for a little assistance.

The specific one I have is this. https://www.ebay.com/itm/2019-Version-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-Signal-Generator/182678167951?ssPageName=STRK%3AMEBIDX%3AIT&var=485227022401&_trksid=p2057872.m2749.l2649 (https://www.ebay.com/itm/2019-Version-Transistor-Tester-LCR-Diode-Capacitance-ESR-meter-Signal-Generator/182678167951?ssPageName=STRK%3AMEBIDX%3AIT&var=485227022401&_trksid=p2057872.m2749.l2649)

It looks like the AY-AT one except it says XR-116 at the top.

I can't for the life of me figure out what version this is. The buffer for the screen is a CD4050bm, Just not sure if it is a ST7735 Display, nor do I know the correct config for the firmware for this. Then to top that off if I need to set the correct fuses. So yea I keep searching, but with so many clones it's hard to make sure I have the correct one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Abacab on August 22, 2019, 08:38:47 am
Thats the AY-AT( same as mine) , the screen is identical as well right down to the J1 symbol next to the pins so its the standard ST7735 Display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on August 22, 2019, 09:25:08 am
Sorry again
Is MK-328 firmware compartible with some other clones?  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 22, 2019, 11:19:17 am
Possibly, if the other clone has the same display (ST7565), MCU (328 at 8MHz), pin assignment and hardware options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on August 22, 2019, 11:42:23 am
Possibly, if the other clone has the same display (ST7565), MCU (328 at 8MHz), pin assignment and hardware options.

What I need to drive it to 16MHz properly?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ledtester on August 22, 2019, 12:49:38 pm
I don't know if this has been mentioned already, but I just found a huge compilation of photos, firmwares and schematics of a large number of transistor tester implementations.

If you have a look at this video starting at the 5 minute mark you'll see the directory structure of this compilation being traversed:

https://youtu.be/efHyRkTYLrE?t=5m

The URL for the archive is mentioned in the video description: https://yadi.sk/d/j7lZdKsPrwTq4Q

Once you download the archive, look in the Все прошивки directory.

Edit: You don't have to download the archive - you can browse it from that web page.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on August 22, 2019, 01:02:56 pm


The URL for the archive is mentioned in the video description: https://yadi.sk/d/j7lZdKsPrwTq4Q

It looks like some russian trojan depository, isn`t it?  :-//

Quote
Foreign files can get to your Yandex.Disk if you log in to someone else’s mobile device. In this case, when startup is enabled, files from the device will be downloaded to Yandex.Disk.

You can stop downloading other people's files to your Yandex.Disk in the following ways:

Log out on all devices
To prevent other people's files from falling onto your Yandex.Disk, exit Yandex.Disk on all devices.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 22, 2019, 01:09:42 pm
What I need to drive it to 16MHz properly?

A 16MHz crystal and a small change in the Makefile (or alternatively the precompiled 16MHz firmware from that russian trojan depository ;)).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 22, 2019, 04:03:17 pm
I don't know if this has been mentioned already, but I just found a huge compilation of photos, firmwares and schematics of a large number of transistor tester implementations.

If you have a look at this video starting at the 5 minute mark you'll see the directory structure of this compilation being traversed:

https://youtu.be/efHyRkTYLrE?t=5m

The URL for the archive is mentioned in the video description: https://yadi.sk/d/j7lZdKsPrwTq4Q

Once you download the archive, look in the Все прошивки directory.

Edit: You don't have to download the archive - you can browse it from that web page.

I already several times placed the reference to the archive with firmwares placed in the Russian storage https://yadi.sk/d/yW8xa5NJgUo5z
This archive is brought together personally by me and does not contain any viruses.
The person who showed the video just copied results of my work.  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 22, 2019, 05:17:41 pm
Yep, indman is the creator of that great collection of images, schematics and firmwares of the various clones.
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirAlucard on August 22, 2019, 06:08:13 pm
Thats the AY-AT( same as mine) , the screen is identical as well right down to the J1 symbol next to the pins so its the standard ST7735 Display.

Thank you for verifying that, that makes it easier to go through the config files for compiling. I was just being thrown through a loop cause the LCD didn't have any marks on it at all, and the K color firmware while working didn't quite fit into the LCD properly.

There really needs to be a post explaining where all the different measurement points are for calibrating and changing the calibration settings. (if there isn't already 233 pages is a lot to read through)

EDIT: So I finally got something to show up on my tester, it loads and verifies v1.36, however whenever I test anything it just shows

Battery?
2: 3mV

I have no idea what that is suppose to mean, but it's not testing any components.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 22, 2019, 08:43:18 pm
That means the tester has tried to discharge whatever might be connected and the voltage at probe pin #2 stays at 3mV. Therefore it  assumes a battery or other power source. If the self-adjustment doesn't help you could increase the threshold CAP_DISCHARGED.
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirAlucard on August 23, 2019, 03:10:27 am
That means the tester has tried to discharge whatever might be connected and the voltage at probe pin #2 stays at 3mV. Therefore it  assumes a battery or other power source. If the self-adjustment doesn't help you could increase the threshold CAP_DISCHARGED.

Alright, at first it started working, set the mv from 3 to 5 just in case, at first when nothing was connected I was correctly getting No Component which was expected. Then when testing a NPN Transistor it correctly identifies. It also worked correctly with a Mosfet. However when I place a 680nF Capacitor across pins 1-3 the thing just shuts down. After that when I removed everything from the tester it now shows up a 29pF Capacitor across 1-2 with nothing being connected.

Also what setting pauses the information screen after it pulls the information? Doesn't seem to sit on it long enough before it tries testing again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 23, 2019, 08:52:28 am
Have you done the self-adjustment? And to have the result stay on screen start the tester with a long key press or enable UI_AUTOHOLD. Please see the README for details.
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirAlucard on August 23, 2019, 04:50:17 pm
Have you done the self-adjustment? And to have the result stay on screen start the tester with a long key press or enable UI_AUTOHOLD. Please see the README for details.

Yea I figured it was the AutoHold, and got that going, but it's actually the self adjustment that does it. So at first start of a fresh flash things work as they should, minus large capacitor amounts shutting the thing down, it still does that. However I found out that if I run the adjustment option, after it's done is when it thinks there is a 22-32pF capacitor across 1-2, also for some reason 2-3 doesn't want to recognize a component connected to it. Or for that matter 1-3. The firmware that I tried using after editing my own configs was the one listed by indman here (https://yadi.sk/d/yW8xa5NJgUo5z). Listed under M328kit+TFT. It still does that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 23, 2019, 05:46:02 pm
Very strange! Maybe a different pin assignment (tester and firmware don't match)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirAlucard on August 23, 2019, 06:17:44 pm
Very strange! Maybe a different pin assignment (tester and firmware don't match)?

The other odd thing is while it doesn't recognize a component connected from 1 to 3, or 2 to 3, it does successfully recognize a PNP Transistor, and a NPN Transistor. As well as mosfets for that matter. So I don't know whats going on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 23, 2019, 08:15:25 pm
SirAlucard,madires
I in such problem cases ask to publish results of hardware T1-T7 tests - it in many respects helps to define a problem source. Do you agree? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 23, 2019, 08:48:41 pm
I do! ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on August 26, 2019, 11:58:28 am
What most progressive TT model for 2019?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 26, 2019, 01:26:55 pm
The other odd thing is while it doesn't recognize a component connected from 1 to 3, or 2 to 3, it does successfully recognize a PNP Transistor, and a NPN Transistor. As well as mosfets for that matter. So I don't know whats going on.

Please enter the menu, run the "test" and post the results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 26, 2019, 01:37:20 pm
What most progressive TT model for 2019?

An AY-AT clone or maybe the Hiland M644 (comes with the extended frequency counter). But for the real fancy stuff you still have to build one yourself.
Title: Re: $20 LCR ESR Transistor checker project
Post by: noremac13 on August 29, 2019, 06:55:29 pm
So I just ordered one of these expecting to use it for troubleshooting capacitors in-circuit but it doesn't seem to work right for that. Maybe I am doing something wrong? It is returning capacitance values that are 3x, 5x, even 10x what is printed on the cap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 29, 2019, 08:02:52 pm
That is to be expected since there's circuitry in parallel with the cap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: noremac13 on August 29, 2019, 09:48:07 pm
That is to be expected since there's circuitry in parallel with the cap.

But I thought the whole point of LCR/ESR meters was their ability to test components while they are still in the circuit?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on August 29, 2019, 11:20:13 pm
Hi,

I have bought a new AY-AT. When i'm calibrate, the values R0= 0.62, 0.64, 0.63
I found these values very high or it's normal ?

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on August 30, 2019, 02:49:23 am
That is to be expected since there's circuitry in parallel with the cap.

But I thought the whole point of LCR/ESR meters was their ability to test components while they are still in the circuit?

Afraid not. That would be quite a device if it could figure out the topology of the circuit, identify the components that are interacting with the one being measured, interpret the behavior of said topology and components, and then infer what the correct value should be rather than the value that is measured.

As a simple example, if you're given a black box with two terminals to measure the capacitance inside, how can you tell how many capacitors there are without looking in the box? You can measure the total capacitance value, but that could be the result of one or a dozen capacitors. Suppose that you open the box and find that there are five capacitors in parallel. How do you measure the value of the middle capacitor? What about the left-most one?

The only reliable way to measure an individual component is to do it in isolation. In-circuit measurement can be useful if you understand the circuit, what you're measuring, and what you're not measuring, in order to get an idea what may be faulty. Then, you confirm your hypothesis by re-measuring out of circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on August 30, 2019, 05:31:49 am
The Hiland Tester with the ATMEGA 644 is down to $16. Time to buy?? :-//
https://www.aliexpress.com/item/32912063006.html?spm=a2g0s.8937460.0.0.816c2e0eN7mWyo (https://www.aliexpress.com/item/32912063006.html?spm=a2g0s.8937460.0.0.816c2e0eN7mWyo)
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirAlucard on August 30, 2019, 07:48:31 am
The other odd thing is while it doesn't recognize a component connected from 1 to 3, or 2 to 3, it does successfully recognize a PNP Transistor, and a NPN Transistor. As well as mosfets for that matter. So I don't know whats going on.

Please enter the menu, run the "test" and post the results.

It doesn't really give me values at the end of it, unless I'm suppose to go to the values section in which case these are what is listed below.

Code: [Select]
Ri- 20.0Ω
Ri+ 22.0Ω
C0 43pF
R0 0.20Ω
Vref 1096mV
Vcc 5013mV *
AComp 0mV

SirAlucard,madires
I in such problem cases ask to publish results of hardware T1-T7 tests - it in many respects helps to define a problem source. Do you agree? :)

What are the hardware T1-T7 tests?
Title: Re: $20 LCR ESR Transistor checker project
Post by: silvestrogatto on August 30, 2019, 08:01:37 am
I have a GM328 (red PCB) Transistor Tester with ST7735 display (pls see attached picture)

I am looking for the original 1.12k firmware.

Is there anyone who made a copy of the original 1.12k firmware that can send me .hex and .eep files?

Thank you!

s.g.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2019, 08:06:50 am
The test function runs several checks (T1...), each check is done 5 times. Note the results (second line) once for each check. It's explained in the README.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 30, 2019, 08:20:06 am
Is there anyone who made a copy of the original 1.12k firmware that can send me .hex and .eep files?
Original mod chinese firmware 1.12k it is locked for read!
Title: Re: $20 LCR ESR Transistor checker project
Post by: silvestrogatto on August 30, 2019, 08:32:12 am
Thank you indman for your prompt reply.

I tried different FW (both compiled and to compile) but no one has the same features of the original one and, even going thru all the changes and settings, I cannot get a 100% hardware compatible and stable firmware running on my tester.

Is there any specific version you recommend for my TT model? Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on August 30, 2019, 10:14:02 am
Hi,

I have bought a new AY-AT. When i'm calibrate, the values R0= 0.62, 0.64, 0.63
I found these values very high or it's normal ?

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2019, 10:16:11 am
Is there any specific version you recommend for my TT model? Thanks!

It's an AY-AT clone. If you like to use the k-firmware please try mega328_color_kit from the repo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2019, 10:24:08 am
I have bought a new AY-AT. When i'm calibrate, the values R0= 0.62, 0.64, 0.63
I found these values very high or it's normal ?

My testers with a ZIF socket have around 0.2 Ohms usually. Have you measured a film cap (220-2200nF) three times before running the self-adjustment?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on August 30, 2019, 11:28:28 am
Hi madires,

I have not try to measure film cap before calibration. Now it's done, but i have again a high values, but the accuracy is good.
Is't possible my encoder has a resistor value ?

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2019, 12:31:28 pm
Encoder? Are you using a rotary encoder to short the probes?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on August 30, 2019, 01:44:09 pm
Hi,

It's my mistake, i have looked the bad schematic. On AY-AT, the encoder is not in parallel with the ZIF.
When i check with a precision multimeter between the ZIP and MCU pin, the resistor is 0.1 ohms.
May be a bad MCU ? The precision is very good. For two resistors 1K @ 0.1%. i.m reading:
1-2 1000 ohms
2-3 1001 ohms   

It's a mystery this 0.6 ohm

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 30, 2019, 03:23:22 pm
Hi,
I have bought a new AY-AT. When i'm calibrate, the values R0= 0.62, 0.64, 0.63
I found these values very high or it's normal ?
Show the photo what you 're using as calibration jumpers? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2019, 03:38:26 pm
It's a mystery this 0.6 ohm

Since it's consistent across all three probe pairs it shouldn't be any issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on August 30, 2019, 04:49:13 pm
Hi,

See picture of the jumper.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 30, 2019, 05:35:46 pm
Andbro,what kind of material is this jumper made of?
What would be the result if you made the same detail out of copper?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on August 30, 2019, 05:45:20 pm

It's a lead of power resistor 2W
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monkeyboi on September 02, 2019, 01:06:20 am
I ordered the GM328A (SMD version) with the black solder mask from a seller on fleabay.  Firmware version is 1.13K.  Biggest piece of snot I've ever bought.  The seller claims it tests SCRs, TRIACs, BJTs, FETs, MOSFETS et al, but it only seems to be able to identify and check BJTs, FETs, MOSFETs and diodes.  It identifies a SCR as an "unknown or damaged part" and it identifies a TRIAC as an NPN BJT.  Darlington BJTs can't be tested or correctly identified either.

When it comes to testing inductors it's a joke. Tested a known good 5H inductor.  It reported the inductance as 46.2H which is not only way off but the meter specs only measures up to 20H.  WTF?  Checking on my DER-5000 LCR meter the inductor reads correctly.  I was wondering what the measuring frequency was of the GM328A so I hooked up my DSO across the part and determined the burst frequency was 1kHz.  So I decided to do a comparison of the inductance reading by setting my DER-5000 LCR meter to measure using the same 1kHz frequency.  Yes the DER-5000 did report the 5H inductor as a higher inductance but nowhere the way off reading obtained by the GM328A.  Curious to see how inaccurate the GM328A module was I measured several other inductors from 100uH upwards and compared them with the DER-5000 using the same measuring frequency.  No surprises, the GM328A was all over the place with its readings.

The capacitance tests didn't fair much better.  Used precision 0.5% micas and various other capacitors from ceramics through to electrolytics to evaluate the accuracy of the GM328A.  Not good at all and ESR measurements were way off.  The resistance tests weren't too inaccurate but give me a Fluke DMM any day.
 
The GM328A has an inbuilt frequency meter.  Found it not too bad for a quick and dirty reading.  Seemed to work well enough to 2.3MHz which is slightly above the claimed spec of 2MHz after which it just reported the same frequency no matter what the actual frequency input was.

The in-built oscillator is a PITA to set the frequency.  Apparently the rotary encoder switch needs a series of timed presses to step up through the ranges.  Fiddly and frustrating to use.

The voltmeter function is polarity conscious.  If you reverse the connections you read 0mV.  :(

General consensus is this gadget has potential if only it worked as described.  |O The one I got is a piece of snot.  Yes, I did run it through the calibration process several times but alas it still has inaccurate readings.

Does anyone know of a model, version number and a supplier of one that actually works as its supposed to?  Recommendations would be much appreciated.  Cheers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: silvestrogatto on September 02, 2019, 09:23:16 am
Thank you madires

Tonight I will try to flash the firmware you suggested and will post the results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 02, 2019, 09:34:04 am
General consensus is this gadget has potential if only it worked as described.  |O The one I got is a piece of snot.  Yes, I did run it through the calibration process several times but alas it still has inaccurate readings.

For limitations of all Transistortester clones please see Karl-Heinz' excellent documentation at https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Monkeyboi on September 03, 2019, 01:43:06 am
Thanks madires for the link to the document.  Most appreciated  :)
It is most informative.

Cheers,
Monkeyboi
Title: Re: $20 LCR ESR Transistor checker project
Post by: SirAlucard on September 04, 2019, 01:27:56 am
The test function runs several checks (T1...), each check is done 5 times. Note the results (second line) once for each check. It's explained in the README.

Alright I have T1, T2, T3, T5 and T6, is there no T7? I realize T4 is just remove the short.

But these are my results.


T1: 1093 on all of the tests

T2: 12 13 23 14 19 19

T3: 12 13 23 2494 2495 864

T5: 0 0 4985 4995

T6: 4990 4990 4995

So on measuring a 1uF capacitor across 2-3 the system shuts down. It also shuts down accross 1-3, but it measures just fine on 1-2. Measuring a .14nF cap across 1-2 works and measures in the ballpark of 140p however measuring 2-3 gives me 49.61uF 130.4 Ohms I_1 20.44uA. If I put that same 140p cap across 1-3 it shows up as 1-2 5pF. I've no idea what's going on.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 04, 2019, 09:01:00 am
Please remove SRV05-4 (IC4) and check again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 04, 2019, 11:50:50 am
T3: 12 13 23 2494 2495 864
In T3 test at you very low indicators - 864 between points 2-3. It means that there are a leak and fault. Here than hardware tests are useful. One of the possible reasons as correctly noticed madires, in fault of protective diode pack of SRV05. T5 test is also not pleasant to me! If you measured not discharged capacitor, then first of all this protective assembly suffers. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2019, 08:35:03 am
May I bother you with a new version of the m-firmware? ;D

v1.37m:
- Fixed error in DS18B20_Tool() when ONEWIRE_IO_PIN is enabled (reported by  Bohu).
- Fixed issue with display of error message on color displays when the watchdog is triggered.
- Added new tool: event counter (HW_EVENT_COUNTER, suggested by Bohu).
- Changed the basic frequency counter to use TestKey() for user feedback.
  Exit counter by two short key presses (was single press).
- Added option to show reverse hFE for BJTs (SW_REVERSE_HFE, suggested by
  towe96@EEVblog). Also added "h_FE_r" command to remote command option.
- Added bitclock setting (BITCLOCK) for avrdude in Makefile (suggested by Bohu).
- Resolved issues with TRIAC detection in case of too high I_GT in Q3 or too high I_H (I_GT issue reported by petroid).
- Moved texts Tester_str, PWM_str, Hertz_str and CTR_str to language specific header files (suggested by indman@EEVblog).
- Changed output of frequency values to use common unit string instead of of split "H" and "z".
- Added option to display key hints (UI_KEY_HINTS), currently just "Menu/Test" (suggegsted by carrascoso@EEVblog).
- Updated Polish texts (thanks to szpila@EEVblog).
- Updated Russian texts (thanks to indman@EEVblog).
- Updated Spanish texts (thanks to pepe10000@EEVblog).

Download the latest version at https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 07, 2019, 06:50:25 pm
Hi,


Do you know this TFT model, i don't remember ?

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2019, 07:04:08 pm
I'd guess it's a ST7735.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 08, 2019, 12:20:44 pm
Hi,

I have upgraded to Markus 1.37. How add a digit to Zener (Voltage) measure ?

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 08, 2019, 02:47:33 pm
Do you mean an additional digit for 10mV resolution? If yes, you can modify Zener_Tool() in tool.c. Remove following line:

Code: [Select]
      Value /= 10;                 /* scale to 0.1V */

And change

Code: [Select]
        Display_Value(Min, -1, 'V');    /* display minimum */

to

Code: [Select]
        Display_Value(Min, -2, 'V');    /* display minimum */
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 08, 2019, 06:26:07 pm
Hi madires,

I have follow your instructions, For a 8.67 Volts, When i push and hold the encoder, the value display is 86.7V and
when i release, i can read 8.67v Min

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 08, 2019, 07:11:41 pm
There's another line to change. From

Code: [Select]
        Display_Value(Value, -1, 'V');

to

Code: [Select]
        Display_Value(Value, -2, 'V');
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 09, 2019, 11:21:11 am

Thanks madires,

the voltage display is perfect at two digits.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 09, 2019, 12:12:54 pm
Andbro, аnd for what to you such accuracy and permission when testing zener? :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 09, 2019, 12:23:12 pm
Hi indman,

My model is a AY-AT and i don't have the zener tester circuit.
I'm using this input for reading a low voltage under 10 volts and not for testing zener.

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: towe96 on September 09, 2019, 02:29:27 pm
Thank you for the reverse hFE addition, works great!

Attached are the .hex and .eep.hex files for 1.37m on my AY-AT clone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 09, 2019, 03:30:42 pm
Hi,


Where we can change the CPU Frequency in 1.37M ?

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 09, 2019, 03:56:14 pm
In the Makefile (FREQ).
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on September 09, 2019, 03:59:29 pm
In the Makefile (FREQ).

sorry
Can I use this firmware with bside ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 09, 2019, 04:06:57 pm
001, you constantly ask children's and silly questions at a forum!  |O
Do not take offense, but this is true.
Understand a simple thing - all clones which are discussed here, imeet the same basic scheme (Except for some additions) and respectively all of them can work with any firmware from Karl - Heinz or madires! It is necessary to compile it just competently.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on September 09, 2019, 05:55:52 pm
001, you constantly ask children's and silly questions at a forum! 

Sory I`m really silly child sometimes. And  I can`t remember some my own yesterday posts
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 09, 2019, 06:22:32 pm
Hi,

I have update my firmware and calibrated. At the start-up i always read a 52pF.
My Show values are:
Ri- 20 - Ri+ 22 - CO 43pF - R0 0,020 - Vref 1113mV - Vcc 5001mV - AC0mp 0mV

Test Menu my values are:
T1 Vref 1113mV
T2 13 4 -1
T3 -10 -20 -24
T5 0 0 0
T4 I can't read, it's too fast
T6 4980 4979 4979


Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 09, 2019, 06:48:58 pm
T2 13 4 -1
T3 -10 -20 -24
Did you correctly write these values?
If it is right, then you have a problem with selection of pairs of measuring resistors of 680 Ohms and 470 kOhm. Check a multimeter their nominal resistance.
In T2-T3 tests of value should be as it is possible closer to 0 and should not have difference one from another more than in 5 units.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 09, 2019, 08:33:19 pm
Hi indman,

The resistors values between the IC  pins and TP are:
Pin14 - TP1 = 682
Pin15 - TP1 = 470K
Pin16 - TP2 = 675
Pin17 - TP2 = 467K
Pin18 - TP3 = 679
Pin19 - T P3 = 469K

When i measure a 1K resistors @ 0.1%   TP1-TP2 = 997.7ohms, TP1-TP3 = 995.7ohms, TP2-TP3 = 999.7 ohms

When i measure 1000uF capacitor, i read TP1-TP2 = 1719uF @ 0.00ohm, TP1-TP3 = 1745uF @ 0.00ohm, TP2-TP3 = 1750uF @ 0.00ohm

In calibration test, it never ask to put a capacitor between 1 and 3, i don't know the Markus Firmware

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 09, 2019, 10:18:36 pm
Hi again....

What is the folder name for the latest Karl Heinz Firmware 1.13K for these ESR ?

Left AY-AT Clone (16Mhz)
Right GM328A (8 Mhz)

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2019, 08:07:54 am
In calibration test, it never ask to put a capacitor between 1 and 3, i don't know the Markus Firmware

Please read the README file included in the source package!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2019, 08:10:49 am
What is the folder name for the latest Karl Heinz Firmware 1.13K for these ESR ?

Left AY-AT Clone (16Mhz)
Right GM328A (8 Mhz)

mega328_color_kit. For 16MHz you have to edit the Makefile and recompile the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2019, 08:31:10 am
Hi indman,
The resistors values between the IC  pins and TP are:
Pin14 - TP1 = 682
Pin15 - TP1 = 470K
Pin16 - TP2 = 675
Pin17 - TP2 = 467K
Pin18 - TP3 = 679
Pin19 - T P3 = 469K
Thank

You have rather high difference in resistance of resistors 680 Ohms and 470 kOhm.
I would advise you to pick up these resistance with closer values to rated. It is desirable to install resistors with the admission of 0.1% or to select from several 1%. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElektroQuark on September 10, 2019, 08:46:15 am
I have no problems reading long threads, but this is insane...
Is there any key messages where I can learn about the best meter version to adquire?
TÍA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 10, 2019, 08:59:56 am


Before to ask a question, do you have read the README ???

You will find all your answer and more.

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 10, 2019, 09:02:57 am
In calibration test, it never ask to put a capacitor between 1 and 3, i don't know the Markus Firmware

Please read the README file included in the source package!



Before to ask a question, do you have read the README ???

You will find all your answer and more. I have begun by the end....

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2019, 12:15:20 pm
I have no problems reading long threads, but this is insane...
Is there any key messages where I can learn about the best meter version to adquire?

Usually you'll find the answer to that common question somewhere in the last 10 pages. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on September 10, 2019, 02:50:43 pm
Hi.

Spanish language update with the new improvements introduced by madires.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jshonw on September 11, 2019, 02:44:31 am
In Windows, I have noticed that you have to manually create the dep directory before compiling the source code for the first time.  It would be nice if this line in the MakeFile could be changed to work on multiple platforms.

-include $(shell mkdir dep 2>/dev/null) $(wildcard dep/*)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElektroQuark on September 11, 2019, 10:44:09 am
I have no problems reading long threads, but this is insane...
Is there any key messages where I can learn about the best meter version to adquire?

Usually you'll find the answer to that common question somewhere in the last 10 pages. ;)
Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ElektroQuark on September 11, 2019, 10:45:00 am


Before to ask a question, do you have read the README ???

You will find all your answer and more.

Thank
I did. No answer found.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 11, 2019, 11:46:58 am
Hi, madires!
Did you check testing of DS18B20 on version 1.37m?
I have actually no DS18B20 therefore I calibrate its simulation in Proteus. Does not work - the cursor blinks though the project works at version 1.35 and temperature is displayed.
The bus OneWire is included also in DS18B20 menu
it is displayed normally:
#define SW_DS18B20
#define ONEWIRE_PROBES             /* via probes */
//#define ONEWIRE_IO_PIN             /* via dedicated I/O pin */

I also attach the updated var_russian.h file with Russian language. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 11, 2019, 11:50:55 am


Before to ask a question, do you have read the README ???

You will find all your answer and more.

Thank
I did. No answer found.
General consensus is this gadget has potential if only it worked as described.  |O The one I got is a piece of snot.  Yes, I did run it through the calibration process several times but alas it still has inaccurate readings.

For limitations of all Transistortester clones please see Karl-Heinz' excellent documentation at https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation.

... did you read the dokumentation from Karl-Heinz also?

Regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 11, 2019, 05:38:27 pm
Did you check testing of DS18B20 on version 1.37m?
I have actually no DS18B20 therefore I calibrate its simulation in Proteus. Does not work - the cursor blinks though the project works at version 1.35 and temperature is displayed.
The bus OneWire is included also in DS18B20 menu
it is displayed normally:
#define SW_DS18B20
#define ONEWIRE_PROBES             /* via probes */
//#define ONEWIRE_IO_PIN             /* via dedicated I/O pin */

Just checked it a few times and it works fine. The only thing I saw is a random misdetection of the pull-up resistor, i.e. the output of the pin assignment flashes very briefly. So I changed the detection a little bit to minimize the misdetection.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 11, 2019, 05:41:27 pm
In Windows, I have noticed that you have to manually create the dep directory before compiling the source code for the first time.  It would be nice if this line in the MakeFile could be changed to work on multiple platforms.

-include $(shell mkdir dep 2>/dev/null) $(wildcard dep/*)

Have you installed cygwin?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jshonw on September 12, 2019, 09:53:12 am
Your right, I  probably should be using cygwin or similar to avoid this problem.  I recently downloaded a new version and it didn't compile properly until I remember that I needed to create the dep dir manually.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alexmel on September 16, 2019, 05:38:21 am
Hi Madires,I have TC-1 with firmware 1.34, how to make measured quartz crystals? Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 16, 2019, 08:58:08 am
For checking quartz crystals with the m-firmware you need the extended frequency counter (hardware option). A clone with that hardware option is the Hiland M644 for example. Or you could use the k-firmware (SamplingADC).
Title: Re: $20 LCR ESR Transistor checker project
Post by: alexmel on September 16, 2019, 10:32:31 am
Thank you, I will try to compile K-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 18, 2019, 02:41:52 pm
Hi!
I compiled the English firmware of m-firmware v1.37m for a clone of AY-AT(GM328A) for 3 clock rates 8,16 and 20 MHz.
Once again great gratitude of madires for its work! :-+
The link for downloading of firmwares here in my storage
https://yadi.sk/d/yW8xa5NJgUo5z/M328Kit+TFT/Firmware/Markus Reschke/English (https://yadi.sk/d/yW8xa5NJgUo5z/M328Kit+TFT/Firmware/Markus Reschke/English)
ATMega328 do not have enough memory any more for all options which were made by madires therefore on a photo I showed the menu of functions which were located in the processor memory.
Also I added into the storage an original firmware from a clone of LCR-TC1 which it was succeeded to read to one of participants of a forum
https://yadi.sk/d/yW8xa5NJgUo5z/LCR%20%D0%A2%D0%A1-1/Firmware/Original (https://yadi.sk/d/yW8xa5NJgUo5z/LCR%20%D0%A2%D0%A1-1/Firmware/Original)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 18, 2019, 02:47:27 pm
chansw,no, this photo will help you? :)

Hi indman, yes, that photo was very helpful, I was able to successfully upgrade the firmware to 1.13. As it turns out on my BSIDE ESR02 device, the header thru-holes were already present. They are V+, Gnd, Reset, SCLK, MISO, MOSI from top to bottom. In fact, I was able to program the unit without having to solder, I just inserted the header pins and applied moderate side-pressure using an elastic band to ensure a good connection, and wired up my USBASP device accordingly.

In my eagerness I neglected to backup the old 1.11 firmware, do you have a copy of the 1.11 hex and eep that you could send to me? I'd like to have it on-hand if I ever need to deal with a warranty issue.

Thank you, you have been super helpful!

Interestingly on my DTU-1701 J6 was exactly the same as yours, all pins present for programming. Where as some have different pins present there and have to tap the resistors for data lines to the MCU.
I've soldered a right angle set of headers so I can easily flash it.

I tried to use my USBASP on that header but AVRDUDE failed with an error, then the 328P Lost its Device Signature. "Device ID 00 00 00"
I managed to recover it with my TL866A ICSP, but thought I'd try again with the USBASP board and exactly the same thing happened again.

*UPDATE*
Just fitted another 328P and flashed with my USBASP and it worked fine, so no idea why it was being strange earlier, might have been manufactured with a dodgy MCU I guess!

Also, I have compiled and uploaded 1.13K Firmware and every power on it says Testing..... and displays a Capacitance reading of 700-1000nf Rather than "no, unknown or damaged component"

All tests seem to be working okay and have run the Selftest etc, capacitor readings are correct. I think it might be stray capacitance as these have multiple connections to the test ports
including the SMD Pads, which will naturally give a reading of capacitance. However the original firmware didn't do this and just said "no, unknown or damaged component"

Wondering if I have missed something when compiling the firmware or a hardware change is needed for the DTU-1701/ESR02?

[attachimg=1]






Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 18, 2019, 08:36:25 pm
Wondering if I have missed something when compiling the firmware or a hardware change is needed for the DTU-1701/ESR02?
Show result hardware test T1-T7
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 18, 2019, 09:04:55 pm
Wondering if I have missed something when compiling the firmware or a hardware change is needed for the DTU-1701/ESR02?
Show result hardware test T1-T7

Thanks for your reply, I actually just tried flashing the pre-compiled 1.13K firmware from your website and it does exactly the same thing.
Here are my results, put them on Gdrive as file size too big to add as attachment on here:
https://photos.app.goo.gl/ivDqj6qX6XTndt9T9

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 18, 2019, 09:10:52 pm
It is not that information which I asked to show.
Read attentively the manual from Karl-Heinz and make hardware T1-T7 tests of the menu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 18, 2019, 09:22:05 pm
It is not that information which I asked to show.
Read attentively the manual from Karl-Heinz and make hardware T1-T7 tests of the menu.

Yes I have read the whole manual, apologies I assumed you meant that data.

Here are the results during calibration:

https://photos.app.goo.gl/u6zxb5uL7mBXJ6Tn7
Title: Re: $20 LCR ESR Transistor checker project
Post by: nigelwright7557 on September 19, 2019, 12:05:16 am
There seems to be a lot of these around now.
I have even seen open source projects for them.
I have a Peak one which is very good for checking components.
The only criticism is the test current is very small due to it using a PP3 battery.
I have a more expensive one that does breakdown voltages.



Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 19, 2019, 07:40:47 am
Here are the results during calibration:

https://photos.app.goo.gl/u6zxb5uL7mBXJ6Tn7

Results of T3-T7 tests - they are very bad!
Check operability of resistors 470 kOhm. Also I will assume that on your board there are traces from soldering, gumboil, dirt or is badly soldered the interface for updating of a firmware. Delete it. It is necessary to look for fault. Good luck.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 19, 2019, 10:16:54 am
Here are the results during calibration:

https://photos.app.goo.gl/u6zxb5uL7mBXJ6Tn7

Results of T3-T7 tests - they are very bad!
Check operability of resistors 470 kOhm. Also I will assume that on your board there are traces from soldering, gumboil, dirt or is badly soldered the interface for updating of a firmware. Delete it. It is necessary to look for fault. Good luck.

Thank you,

It's working now, I de-soldered the pin header from J6! Ran the calibration again and it's working correctly.
Just flashed the 16MHz 1.13K firmware from your site and that works perfectly now.

*UPDATE*

Just ran it again and the fault has come back, swapped the MCU for a brand new one from a different batch and still the same.
All resistors check out fine, can only assume this is a bad design and has stray capacitance as it has a lot of inputs tied together.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 19, 2019, 11:24:47 am
All resistors check out fine, can only assume this is a bad design and has stray capacitance as it has a lot of inputs tied together.
At BSideESR02(DTU1701) quite successful design, it does not cause in other owners in work any problems. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 19, 2019, 11:35:10 am
All resistors check out fine, can only assume this is a bad design and has stray capacitance as it has a lot of inputs tied together.
At BSideESR02(DTU1701) quite successful design, it does not cause in other owners in work any problems. :)

My DTU-1701 has a different PCB design to the ESR02 models I have seen, mine has V+, Gnd, Reset, SCLK, MISO, MOSI at J6 but the ESR02 models I have seen
only have V+, Gnd, Reset at J6 and I think 1,2,3 DUT pins are present there.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on September 19, 2019, 04:58:09 pm
All resistors check out fine, can only assume this is a bad design and has stray capacitance as it has a lot of inputs tied together.
At BSideESR02(DTU1701) quite successful design, it does not cause in other owners in work any problems. :)

My DTU-1701 has a different PCB design to the ESR02 models I have seen, mine has V+, Gnd, Reset, SCLK, MISO, MOSI at J6 but the ESR02 models I have seen
only have V+, Gnd, Reset at J6 and I think 1,2,3 DUT pins are present there.

Do U has a photo?
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 19, 2019, 05:27:42 pm
Do U has a photo?

Yes, here is a picture of the DTU-1701, you can see J6 goes to the MCU which is different to the Bside ESR02.
I think these are a cheap clone to be honest, it was only £16.

Ignore the missing caps C10/C12 I removed them for testing, also I pulled the MCU off.
On J6 I cut the traces going to the MCU as I thought that might be causing problems.

Last picture is of a BSide ESR02 that sorenkir posted on this forum, the PCB layout is different.
DTU-1701
[attachimg=1]
[attachimg=3]

BSide ESR02
[attachimg=2]
Title: Re: $20 LCR ESR Transistor checker project
Post by: radit68i on September 22, 2019, 07:25:17 pm
Look what happens on BSIDE ESR02 when measure not discharged electrolytic capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on September 22, 2019, 08:15:08 pm
Look what happens on BSIDE ESR02 when measure not discharged electrolytic capacitor.

Impressive hole :)
That would happen on any of these to be honest, unless you have input protection.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 23, 2019, 06:54:47 am
Hi madires!  :)
Still I have one question on future development of the project. Whether it is possible to make additional point in the menu in order that it was possible to measure in the cyclic mode capacitors, resistors, inductance on test contacts 1-3? And that the tester updated in the cyclic mode only results of measurement and the display not to redraw? Such mode is more convenient for observation of smooth changes of results of measurements during a certain period.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 23, 2019, 05:15:35 pm
IIRC, that's already on the to-do list. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on September 30, 2019, 01:57:42 am
Good video from Andreas and worth a watch.

https://www.youtube.com/watch?v=4Xsg8lpP75s (https://www.youtube.com/watch?v=4Xsg8lpP75s)
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on October 10, 2019, 07:25:03 pm
Hi

My DER DE5000 reads choke as 49ohm DC and 5.6Hy
But BSIDE ESR02  says 51ohm DC and 10Hy
What I`m doing wrong?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 10, 2019, 09:39:01 pm
First you should get rid of the "y". ;) The LCR meter uses a different method for measuring inductance than the transistor tester. Also the frequency of the test signal and the mode (serial/parallel) have an impact on the result. Have you selected the right mode for a large inductance? Anyhow, the transistor tester can't measure inductance as accurate as a proper LCR meter because of its simple design.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on October 11, 2019, 10:02:06 am
Have you selected the right mode for a large inductance? 

What a "large inductance mode" is? How to activate it?  :-//

ESR02PRO is marked 0.01mH-20H on a front panel
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 11, 2019, 11:29:39 am
001, madires and i explained russian forum to you that ESR02PRO will inflate readings inductance coils for more than 1H. If these results do not suit you, then complain to ESR02PRO manufacturer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on October 11, 2019, 11:57:24 am
001, madires and i explained russian forum to you that ESR02PRO will inflate readings inductance coils for more than 1H. If these results do not suit you, then complain to ESR02PRO manufacturer.

Why? I read authors manual and it says about -10% for L above 1H and  -20% for L above 10H
But I got +100% for 5H!


[attachimg=1]
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2019, 12:24:29 pm
What a "large inductance mode" is? How to activate it?  :-//

ESR02PRO is marked 0.01mH-20H on a front panel

I was talking about the LCR meter (DE5000). I don't have that model, but most have a button to select between serial and parallel measuring mode. Serial mode is meant for low impedance and parallel for high impedance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on October 11, 2019, 12:28:45 pm
What a "large inductance mode" is? How to activate it?  :-//

ESR02PRO is marked 0.01mH-20H on a front panel

I was talking about the LCR meter (DE5000). I don't have that one, but most have a button to select between serial and parallel measuring mode. Serial mode is meant for low impedance and parallel for high impedance.

DE5000 is ok. I use it everyday. And choke is factory marked as 5H
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on October 15, 2019, 05:06:51 am
ttester was mentioned recently on the 'Andreas Spiess' Youtube channel. He thinks very highly of the developers.
Andreas does mostly microcontroller, sensor, and RF stuff. Worth a look.


https://www.youtube.com/watch?v=4Xsg8lpP75s (https://www.youtube.com/watch?v=4Xsg8lpP75s)

It was also featured on Hackaday (back in 2015. Wow it's been going a while):
https://hackaday.com/2015/04/24/review-transistor-tester/ (https://hackaday.com/2015/04/24/review-transistor-tester/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 15, 2019, 01:11:35 pm
One page back beanflying linked the video already. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on October 16, 2019, 04:06:35 am
it's worth mentioning again  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Macbeth on October 16, 2019, 10:28:29 pm
it's worth mentioning again  :)
If Andreas Spiess is worth mentioning again, so is Dave who chucked it aside in a prior mailbag video and copped a lot of flack for it!
https://www.youtube.com/watch?v=7Br3L1B80ow (https://www.youtube.com/watch?v=7Br3L1B80ow)
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on October 16, 2019, 11:19:20 pm
Given the heft of this thread it might be worth seeing if @torch if he is still reading could mod his opening post a little to include them there. Or better yet make the opening post partly a curated index to notable content or resources?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rhb on October 16, 2019, 11:37:12 pm
Why not step up the game and test breakdown voltages and provide curve tracing and data output via ASCII over a USB serial port?

BSIDE has the AVR based OSSW/OSHW covered at a good price.  Peak has considerably more to offer in the DCA75, though not as good a package as the BSIDE.  But neither will measure breakdown voltages and a large number of other important datasheet parameters.

Really, this is all so "last year".

;-)
Reg
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on October 16, 2019, 11:44:38 pm
Why not step up the game and test breakdown voltages and provide curve tracing and data output via ASCII over a USB serial port?

BSIDE has the AVR based OSSW/OSHW covered at a good price.  Peak has considerably more to offer in the DCA75, though not as good a package as the BSIDE.  But neither will measure breakdown voltages and a large number of other important datasheet parameters.

Really, this is all so "last year".

;-)
Reg

Peak shmeak everyone needs to just needs to get lucky or pony up for one of these. Arriving in my shack early next week  ;D Or add one of the Thai made curve tracers to your collections eBay auction: #291319027845

(https://i.ebayimg.com/images/g/cOcAAOSwLxldTOml/s-l1600.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on October 17, 2019, 04:03:40 am
Dave who chucked it aside in a prior mailbag video

True but didn't he revisit it in another video a short time later after he learned some details, and decided it was actually cool.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on October 17, 2019, 04:17:09 am
Why not step up the game and test breakdown voltages
That is an extension explained in the documention.

provide curve tracing
overkill

data output via ASCII
Pretty sure it does as of a few updates ago.

Many people have suggest that the tester should also do x, y and z. The answer is still the same: You missed the minimalist point of the project. It's intended to run on basic hardware, low part count, and low cost. You can easily breadboard it. Any fool can over-engineer something.

But it is open source so have at 'er.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 001 on October 17, 2019, 04:15:19 pm
Why not step up the game 

Done
https://www.youtube.com/watch?v=PiM1qX1G1Is&feature=youtu.be (https://www.youtube.com/watch?v=PiM1qX1G1Is&feature=youtu.be)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rhb on October 17, 2019, 06:39:25 pm
I scavenged some semiconductors out of an electronic fluorescent lamp ballast.  They were marked, so I was able to look up the datasheets.  A couple of the parts were BJT switching transistors with a 700 Vces breakdown and 400 Vceo sustaining.  Digikey stocks them for $1.10.

The BSIDE and the Peak told me a bit about them, but mostly just that they  still appeared functional.

I happen to think it might be useful to be able to measure more datasheet parameters than the BSIDE or Peak can.    And I don't want an analog curve tracer.  I want to put a part in a fixture, close the lid, generate a datasheet for it, put it in a numbered bag and add it to a parameter searchable inventory even if it is a house marked part.  And not spend $20k+ for being able to do that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on October 18, 2019, 01:20:02 pm
I want to put a part in a fixture, close the lid, generate a datasheet for it

Me too!
Title: Re: $20 LCR ESR Transistor checker project
Post by: BradC on October 18, 2019, 02:33:24 pm
I want to put a part in a fixture, close the lid, generate a datasheet for it

Me too!

It's open source and there are two of you, should be a doddle.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rhb on October 18, 2019, 08:38:11 pm
Yeah, sure. Piece of cake.

You design a digitally adjustable HV supply and get back to me about how easy it was. Next generate pulses 50-500 us long with a 1-2% duty cycle at up to 1 A and measure the voltages and currents.  Then collect all the datasheet parameters and curves.  Take a look at the manual for a Tek 57x curve tracer for how it was done 50 years ago.

Go price an Agilent 4155A or 4156A  used on ebay.  The Arduino based tester is very nice.  But I'm suggesting that something much more capable can be built for $100-200.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on October 20, 2019, 03:32:20 am
mentioned again @ 16:50


https://www.youtube.com/watch?v=IAQClL3bZzg (https://www.youtube.com/watch?v=IAQClL3bZzg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: beanflying on October 20, 2019, 03:42:09 am
For those wanting a better component whizbang datasheet generator go start your own thread and by all means link it here but glorified Arduino run from batteries is NEVER going to be the hardware or the place to make it happen. It is what it is and in spite of owning two sets of expensive LCR tweezers mine is still seeing some use in my on site bag.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 20, 2019, 02:47:00 pm
Yep, we have no intention to develop a Transistor Tester HV Ultra. That might be an idea for a commercial product, and I doubt such a tester would be inexpensive. It would be also a niche product with a market for just a few units. The success of the current design is based on its simplicity and low cost. It makes my happy that so many people can afford a transistor tester helping them to repair electronics or to upcycle components.
Title: Re: $20 LCR ESR Transistor checker project
Post by: blurpy on October 23, 2019, 05:13:44 pm
I bought a GM328 kit from Banggood, but they didn't send me all the capacitors, and their support person was not very helpful.
I need to get hold of a matching capacitor for the free spot on the top by the terminal.

The assembly instructions lists this:
ceramic capacitor
 100nF 20%
 silk( 104)
 RAD0.2

There is no mention of voltage rating here, and I'm not sure if it's important or not. Will 104s with a 50v rating work ok?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 23, 2019, 05:52:22 pm
Your kit is an AY-AT type clone and the missing cap is the bypass cap for AVCC which is 5V. So a 50V 100nF MLCC would be fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: blurpy on October 23, 2019, 06:06:53 pm
Your kit is an AY-AT type clone and the missing cap is the bypass cap for AVCC which is 5V. So a 50V 100nF MLCC would be fine.

Thank you  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Phenixg on October 29, 2019, 03:52:41 pm
Have any of you guys checked how accurate this similar product "LC100-A Digital LCD High Precision Inductance Capacitance L/C Meter" is  compared to the AY-AT? It is only limited to L and C measurements and it is boasting some impressive characteristics.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 29, 2019, 05:48:14 pm
That L/C meter is based on an oscillator and frequency counter. Therefore it's more accurate, but it can't measure additional parameters. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 31, 2019, 08:25:32 pm
Mr. Bohu has compiled an extended documentation for the m-firmware from a user's perspective, explaining settings and more. He has created a German and English version which are available via https://github.com/madires/Transistortester-Warehouse.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on November 01, 2019, 06:34:23 pm
Just a quick question-

Has any thought been given to using a 328PB?

Ralph S Bacon has a video on a board he made that plugs directly into an Uno board (or anyplace the dip goes) and breaks out the extra GPIO pins,

https://www.youtube.com/watch?v=S_k_2sqmSxw&t=0s (https://www.youtube.com/watch?v=S_k_2sqmSxw&t=0s)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 01, 2019, 09:11:42 pm
The additional I/O pins, timers and interfaces of the 328PB are nice for hardware options, but the flash memory of 32kB limits what can be added. With a graphics display and several options enabled the firmware is larger than 32kB.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on November 01, 2019, 10:42:41 pm
Finally I flashed my TC-1 (with 644P inside) with markus' lates FW (1.37). But the tester powers of after testing very quickly. So quickly that I'm not able to see the measurement result. How can I change it?



@all who have problems flashing 8051
If you aren't able to connect, short VCC and GND on PCB side to discharge capacitators and try again. Afterwards I was able to connect to the µC
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2019, 09:54:35 am
Have you programmed the control MCU U4 with https://github.com/atar-axis/tc1-u4? And have you used the settings listed in the Clones file?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on November 02, 2019, 12:44:43 pm
U4 was successfully programmed and settings like in "clone"File. Everything was done like you write it in the readme file. Only diffrence my TC1 has got a 644P and not a 324 inside.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 02, 2019, 02:06:06 pm
Finally I flashed my TC-1 (with 644P inside) with markus' lates FW (1.37). But the tester powers of after testing very quickly. So quickly that I'm not able to see the measurement result. How can I change it?
Have you read the madires tester guide carefully? Tester can operate in 2 modes - cyclic and manual. Hold the Test button start for more than 1 second and the manual mode will work. You can change these settings in config.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on November 02, 2019, 02:29:54 pm
Finally I flashed my TC-1 (with 644P inside) with markus' lates FW (1.37). But the tester powers of after testing very quickly. So quickly that I'm not able to see the measurement result. How can I change it?
Have you read the madires tester guide carefully? Tester can operate in 2 modes - cyclic and manual. Hold the Test button start for more than 1 second and the manual mode will work. You can change these settings in config.h.

No I didn't see this feature and still can find it in config.h  :-// Can you give me a line where it is?
But tester also power offs after one measurement (one cycle). I guess it isn't my problem. Before I already tried to change cycle times but without any affect.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2019, 02:51:33 pm
If the tester powers off after the first run something else wrong. Any warning about a low battery? Are you sure that U4 is programmed with the alternative firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on November 02, 2019, 04:33:10 pm
I want to ask dear Madires, how can I assign a port to connect the IR diode transmitter in the Hiland clone? I want to put with a transistor for constant use. Thank!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2019, 08:46:51 pm
The signal output has to be OC1B which is also PD4 in case of an ATmega324/644. Since the Hiland M644 uses PD4 for the low value test resistor of probe #2 you can't have a dedicated pin for signal output. One idea might be to add a switch to probe #2 for the IR driver transistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on November 03, 2019, 11:04:13 am
I get it, thanks.
If it's not difficult, add two fonts, 8 thin and 12 thin, to your source.
Another question is how to swap Menu items? I do not like that first Shutdown, then Exit.
Can I change the order of the Menu items? How to do it? Thank!
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 09, 2019, 03:34:43 am
Hi chaps :)

Does anyone have the required knowledge to tell me how to re-flash a "fish8840tft" (photo attached) so that I may enabled the PWM & sq wave generator functions, plus the other extras that are on the mass produced clone (the one with the mint green backlit LCD and orange PCB)? I'm okay with compiling source and github/trees and all that stuff, if needed. I just bought this nice little unit - also the spelling of "Unknown" being "unKNOW" in this one, bugs me like crazy... also the spindly thin font used is VERY harsh on the eyes - can that be modified?

Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 09, 2019, 10:43:36 am
If it's not difficult, add two fonts, 8 thin and 12 thin, to your source.
Another question is how to swap Menu items? I do not like that first Shutdown, then Exit.
Can I change the order of the Menu items? How to do it? Thank!

Thanks for the fonts! To swap items in the main menu simply swap the code blocks for menu items in function PresentMainMenu() in user.c. In your case please change:
Code: [Select]
  #ifdef SW_POWER_OFF
  MenuItem[Item] = (void *)PowerOff_str;     /* power off tester */
  MenuID[Item] = 20;
  Item++;
  #endif
  MenuItem[Item] = (void *)Exit_str;         /* exit menu */
  MenuID[Item] = 0;
  Item++;                                    /* add 1 for item #0 */
to
Code: [Select]
  MenuItem[Item] = (void *)Exit_str;         /* exit menu */
  MenuID[Item] = 0;
  Item++;
  #ifdef SW_POWER_OFF
  MenuItem[Item] = (void *)PowerOff_str;     /* power off tester */
  MenuID[Item] = 20;
  Item++;
  #endif
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 09, 2019, 11:07:57 am
Does anyone have the required knowledge to tell me how to re-flash a "fish8840tft" (photo attached) so that I may enabled the PWM & sq wave generator functions, plus the other extras that are on the mass produced clone (the one with the mint green backlit LCD and orange PCB)? I'm okay with compiling source and github/trees and all that stuff, if needed. I just bought this nice little unit - also the spelling of "Unknown" being "unKNOW" in this one, bugs me like crazy... also the spindly thin font used is VERY harsh on the eyes - can that be modified?

Add an ISP header and choose a firmware. You could use a precompiled 1.13k (mega328_fish8840) or compile a 1.37m (see Clones file for settings, Fish8840 is listed). And yes, different fonts are possible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 09, 2019, 01:00:39 pm
Add an ISP header and choose a firmware. You could use a precompiled 1.13k (mega328_fish8840) or compile a 1.37m (see Clones file for settings, Fish8840 is listed). And yes, different fonts are possible.
I will slightly add the answer of the respected madires - you have one of the varieties of clone Fish8840 with TFT display.  :) . On my resource in the Fish-8840TFT folder there are ready English firmware, eti look carefully
https://yadi.sk/d/yW8xa5NJgUo5z/Fish-8840TFT
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 09, 2019, 06:55:09 pm
Add an ISP header and choose a firmware. You could use a precompiled 1.13k (mega328_fish8840) or compile a 1.37m (see Clones file for settings, Fish8840 is listed). And yes, different fonts are possible.
I will slightly add the answer of the respected madires - you have one of the varieties of clone Fish8840 with TFT display.  :) . On my resource in the Fish-8840TFT folder there are ready English firmware, eti look carefully
https://yadi.sk/d/yW8xa5NJgUo5z/Fish-8840TFT

Thank you ever so much. Could you also provide the source files from which this was compiled, since it's not in the ZIP, thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on November 09, 2019, 07:55:05 pm
* .Zip only files that are modified for your clone. All source codes - https://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 10, 2019, 01:30:10 am
* .Zip only files that are modified for your clone. All source codes - https://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/)

Thanks so much for that, appreciate it a lot :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Altair8800 on November 11, 2019, 07:42:08 am
Hi All,

I'm looking to purchase one of these LCR Component Transistor+ testers.  Hopefully under $30 USD.  Any suggestions? 

I'm just a beginning Electronics hobbyist. 

Is there any list or database that kind of compare all these different versions (TC1, TC4, TC7, ESR02, 574D, other?)?  Like what their features/specifications are.  I assume not all are created equal (like some do not do Inductance or are older versions).

Thanks,


PS:  I like what this Aussie guy did to modify his component tester to quickly use different types of probes.
https://www.youtube.com/watch?v=nloopuHbWAs (https://www.youtube.com/watch?v=nloopuHbWAs)

PS2:  Please forgive me for not reading all 239 pages of this 7 year old continuous updated thread.    :-[  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 11, 2019, 09:35:25 am
Please see https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2295804/#msg2295804 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2295804/#msg2295804) for indman's overview of clones.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 11, 2019, 11:34:43 am
Here I made a more recent version of the table  :)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2456181/#msg2456181 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2456181/#msg2456181)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Altair8800 on November 11, 2019, 02:22:26 pm
Thanks indman for the time to make the list and madires for the mention.   :-+ :-DMM
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 11, 2019, 06:10:25 pm
So here's an odd thing or two: I removed the battery from my Fish8840TFT, connected my USBASP to the 6-pin header, and immediately the red USBASP LED extinguished, and the Fish8840TFT wouldn't turn on. After a brief search of this thread, I surmised that the zener (legend marked as "3v3") which is marked "Z14" on its body, had been blown by the transients inflicted by the USBASP :-/ - so I lifted the top (middle) leg off the board, et voila - she sprang back to life! ( the post mentioning this issue is here ---> https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1610944/?topicseen#msg1610944 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1610944/?topicseen#msg1610944)

Okay, so I flashed the Fish8840TFT firmware kindly supplied by indman ---> https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2776962/#msg2776962 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2776962/#msg2776962) and a very odd thing is happening (pic attached); the upper 2 or 3 lines of the TFT have what I can only compare to "TV snow" on them, AND also the tester says "Bat 16v" - and that's only when it's connected to the 9v battery - when I am powering it via the header, from the USBASP, it reports as normal. Odd...

Ideas?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 11, 2019, 06:58:33 pm
eti look https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1532846/#msg1532846 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1532846/#msg1532846)
In the Karl-Heinz distribution kit there is no support of a clone of Fish8840TFT. In order that its firmware worked it is necessary to make considerable changes in the config.h file.
In order to correctly measure the battery voltage, you need to configure the control parameters in makefile
# Voltage divider for battery voltage measurement  10k / 3.3k = 133/33
CFLAGS  = -DBAT_NUMERATOR=133
CFLAGS  = -DBAT_DENOMINATOR=33
Title: Re: $20 LCR ESR Transistor checker project
Post by: ansic on November 11, 2019, 11:21:51 pm
I purchased a T4 which arrived broken.  There was no backlight at first, there was a "Testing.." text when the button was held down.  Nothing would happen past that.  If the button was released the tester shut down instantly.  Seemingly randomly the tester would function for a couple seconds.

After flashing the chip, both the M and K version, with various configurations, sometimes it worked for a while, a full calibration went through but after the next boot, nothing would show up on the display.  It *did* identify components correctly a few times, both resistors and capacitors.

The tester is totaled now.  After applying 5V to the LM7805 regulator output, 1.5A of current was rushing through a SOT23 device and thus burning my finger. 

Does anyone know what the three SOT23 devices close to the 9V input are?  The silkscreen says 9014 and 9015, the print on the device is J6 and M6.
Title: Re: $20 LCR ESR Transistor checker project
Post by: LateLesley on November 12, 2019, 01:06:20 am
It looks like they are SOT23 versions of the 2SC9014, and 2SC9015. If you look for MMBT9014 and MMBT9015, you find them in SOT23 format.


https://www.aliexpress.com/item/32626794124.html (https://www.aliexpress.com/item/32626794124.html)

http://www.aliexpress.com/item/32853116372.html (http://www.aliexpress.com/item/32853116372.html)

https://alltransistors.com/pdfview.php?doc=mmbt9014lt1.pdf&dire=_upd (https://alltransistors.com/pdfview.php?doc=mmbt9014lt1.pdf&dire=_upd)

https://alltransistors.com/pdfdatasheet_upd/mmbt9015lt1.pdf (https://alltransistors.com/pdfdatasheet_upd/mmbt9015lt1.pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ansic on November 12, 2019, 12:48:00 pm
Replaced the transistors but the problem is a short from 5V rail to ground, 1.4 ohm.  The trace disappears under the atmega328p so without de-soldering the chip its difficult to guess where it goes next.  LM7805 was not the fault.  Could it be a short inside the atmega chip or the LCD?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 12, 2019, 02:06:29 pm
some people have reported shorts on their PCBs
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 12, 2019, 09:24:40 pm
I purchased a T4 which arrived broken.  There was no backlight at first, there was a "Testing.." text when the button was held down.  Nothing would happen past that.  If the button was released the tester shut down instantly.  Seemingly randomly the tester would function for a couple seconds.

After flashing the chip, both the M and K version, with various configurations, sometimes it worked for a while, a full calibration went through but after the next boot, nothing would show up on the display.  It *did* identify components correctly a few times, both resistors and capacitors.

The tester is totaled now.  After applying 5V to the LM7805 regulator output, 1.5A of current was rushing through a SOT23 device and thus burning my finger. 

Does anyone know what the three SOT23 devices close to the 9V input are?  The silkscreen says 9014 and 9015, the print on the device is J6 and M6.

Maybe these Chinese manufacturers could make and sell a transistor tester, tester. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ansic on November 13, 2019, 04:49:51 pm
The short was in the atmega328p chip itself. 1.8 ohm from VCC to GND measured after taking the chip off with a hot air gun.  To replace it I only have atmega3208 chips which have a different pinout (and architecture..!)
Title: Re: $20 LCR ESR Transistor checker project
Post by: capitainekurck on November 14, 2019, 11:36:10 am
Hello all

I new on this forum.
I bought one of there tester on ebay.
I receive it yesterday it work 5 or 10 minutes and it fail. i was trying to check some resistor and led to test it (not capacitors) and suddenly it stop to work. it don't turn on any more. The battery is full load. when i push the button to power it on, the  screen become white ( it normally black when it power off) and it turn black few seconds after.

Is it the same problem as yours or for you the display stay black ?

regards
L.S.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2019, 12:47:14 pm
If just the backlight turns on the MCU isn't running. The TC clones are known for shorted MLCCs in the power supply circuitry. And some have a Schottky diode with a too low reverse voltage for the Zener test voltage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: capitainekurck on November 14, 2019, 01:43:31 pm
hello thanks for you reply. is there a way to fix it or is finitely dead.

you mean C11 et C12 capacitors. the one i receive seem to be T7 on the box but the pcb seem yo be the TC1
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2019, 03:17:28 pm
Yep, same PCB. C11, C12, D2 and the MLCCs around the 5V regulator. It shouldn't be hard to find the culprit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: capitainekurck on November 14, 2019, 04:39:11 pm
i test C8 C9 C10 c11 c12 c14 c15 without de soldering them with my multimeter. they don't seem to be shorted. i plug the bat an i test the 5 V on the AVCC from the MEGA and the 5 volt is correct. while i was making the measures it start normally on time and fail each time after.

I'm not an electronician, just a hobbyist)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2019, 06:26:09 pm
Maybe a bad solder joint?
Title: Re: $20 LCR ESR Transistor checker project
Post by: capitainekurck on November 15, 2019, 10:26:25 am
i don't know, hard to find . all components are surface mount. yesterday it work for 3 or 4 minutes and stop again. this morning it work since 2 or 3 hours. I cant find what's going wrong. |O

perhaps it the MCU who got a problem
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on November 15, 2019, 08:50:34 pm
If the tester powers off after the first run something else wrong. Any warning about a low battery? Are you sure that U4 is programmed with the alternative firmware?

Sorry for my  late reply.
I'm sure that is U4 programmed and even correctly.

And in my opinion it is also no low battery because I see also "ciao" message. Measurement result is shown for about 0.5s and also "ciao" screen for 0.5s. As I told in my prviews postings, my tester has no Mega324 inside, like TC1 has normaly. It has 644 inside.
Any proposal?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 15, 2019, 09:15:36 pm
There could be something wrong with the setting of TEST_BUTTON or the button signal, i.e. the firmware thinks the button is pressed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on November 15, 2019, 10:31:12 pm
There could be something wrong with the setting of TEST_BUTTON or the button signal, i.e. the firmware thinks the button is pressed.

Yeah :) U R right :) On PD0 is constantly +5V and switch isn't connected to PD0 as in clones config. I'll try to figure out what has been changed next week.

Edit: PD0 isn't for power on. It was my fault ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: capitainekurck on November 16, 2019, 12:24:54 pm
Now mine sometime work sometime don't work. sometime the mcu seem boot and an other time it seem don't boot.
Dot you think it a problem of the mega that can be damage or something in the power. it correctly power with the 5 V. when it don't  boot the 5V seem to be correct
I will change C11 and C12 because there is a lot of post that said there a often the culprit but I'm not sure that is the problem. 

an other thing. if i remember well, the fist time i power it on when it arrive there was a sreen with the version of the firmware. now when it boot up there is a blank white screen a very quick "garbage" screen and the test screen
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 16, 2019, 03:12:45 pm
Now mine sometime work sometime don't work. sometime the mcu seem boot and an other time it seem don't boot.
Dot you think it a problem of the mega that can be damage or something in the power. it correctly power with the 5 V. when it don't  boot the 5V seem to be correct

Another cause could be the brown out detection (see e-fuse). Try a lower threshold. I had to adjust the BOD for one TC-1 to make it work.

I will change C11 and C12 because there is a lot of post that said there a often the culprit but I'm not sure that is the problem. 

As long as they aren't shorted they won't cause any trouble for the 5V rail. The flyback transformer powers the 5V rail and the Zener test (up to 50V). But it's a good idea to replace C11 and C12 because of the known DC bias problem of MLCCs. You won't get MLCCs spec'd for higher voltages in the same package size.

an other thing. if i remember well, the fist time i power it on when it arrive there was a sreen with the version of the firmware. now when it boot up there is a blank white screen a very quick "garbage" screen and the test screen

I can't say much about the modified firmware the TC-1 comes with. As soon as the 5V rail is available the LEDs for the backlight are powered (blank screen) and after the MCU started the firmware initializes the display. When the display's RAM isn't cleared before enabling the display's output you'll see random pixels briefly. It's an annoying feature of the ST7735.
Title: Re: $20 LCR ESR Transistor checker project
Post by: capitainekurck on November 16, 2019, 04:05:11 pm
"Another cause could be the brown out detection (see e-fuse). Try a lower threshold. I had to adjust the BOD for one TC-1 to make it work."

Sorry i don't understand. Where is the e-fuse and how to lower is threshold.

for C11 and C12 i will not use SMD i find on an other post that someone use an electrolytic 10µf 100V and a ceramic 100nf 100v.

In a other way if i can fix it and i decide to buy an other what is the best clone i can take to flash the last m-firmware with all option (changing the mega if it need to have enough memory)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 16, 2019, 04:48:17 pm
The ATmega has a few special configuration bytes, like the extended fuse byte. Check the documentation of your ISP programmer for changing the fuse bytes. The ATmega's datasheet explains the fuse bytes in detail.

The best choice for clones is the AY-AT (ATmega328) or the Hiland M644 (ATmega644, monochrome display) at the moment. They aren't perfect, but ok.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 17, 2019, 03:18:25 am
Hi.

When I got my LCR-T4 (generic, beautiful peppermint green backlit mono LCD, orange PCB, the one you see everywhere) it came with "MTester" firmware - I backed it up using avrdude. The I flashed in another build, and when I did so, efuse value of 0xfc was complained about, and it asked for 0x04, so I set it to 0x04; I understand that is something to do with differing revisions of the atmega 328, and the efuse would still work ok?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 17, 2019, 11:45:22 am
0xfc is fine. The 0x04 is caused by a known issue in avrdude's configuration file. Simply ignore it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 17, 2019, 06:40:35 pm
0xfc is fine. The 0x04 is caused by a known issue in avrdude's configuration file. Simply ignore it.

Thanks every so much, I hope you're enjoying your weekend  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: capitainekurck on November 18, 2019, 02:21:03 pm
The best choice for clones is the AY-AT (ATmega328) or the Hiland M644 (ATmega644, monochrome display) at the moment. They aren't perfect, but ok.

do you mean this one ?
https://fr.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html?rmmds=search&cur_warehouse=CN (https://fr.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html?rmmds=search&cur_warehouse=CN)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2019, 02:52:00 pm
Yep, it has a boost converter for the the Zener test, the extended frequency counter without input buffer and a built-in adjustment cap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 18, 2019, 05:45:16 pm
Okay, since this thread is SO MASSIVE, and since things aren't always explained clearly and in steps (or maybe it's me?) I am struggling to find a clear tutorial as to what needs editing (Makefile? config_328.h?) and how, how one goes about compiling, etc... little fragments of the whole bigger picture are scattered everywhere through the thread, and I value all the hard work, but I am struggling to find an "Step 1, Step 2, Step 3..." kind of beginner's guide for firmware compilation (and also we need to know the FULL avr-gcc commands and arguments supplied to it).

If someone could kindly help, thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2019, 08:37:15 pm
1. edit Makefile
2. edit config.h
3. edit config_328.h for an ATmega328 or config_644.h for 324/644/1284
4. run "make"
5. run "make upload"
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 19, 2019, 03:06:24 am
1. edit Makefile
2. edit config.h
3. edit config_328.h for an ATmega328 or config_644.h for 324/644/1284
4. run "make"
5. run "make upload"

So just to clarify, there exists both "config.h" *and* "config_<mcu_part>.h", or is your "3. " step a mere extension of step "2. ", and there's only ONE config .h file?

Thanks :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 19, 2019, 11:17:26 am
config.h and config_<MCU>.h are two different files. In config_<MCU>.h you'll find all MCU specific settings like pin assignments (including the display), and config.h is for features and all other settings. BTW, this is explained in the README file (see "Building the firmware").
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 19, 2019, 02:42:24 pm
config.h and config_<MCU>.h are two different files. In config_<MCU>.h you'll find all MCU specific settings like pin assignments (including the display), and config.h is for features and all other settings. BTW, this is explained in the README file (see "Building the firmware").

Ah  okay, I'll have a look, thanks again so much. :))
Title: Re: $20 LCR ESR Transistor checker project
Post by: ansic on November 22, 2019, 01:57:02 pm
The replacement LCR-T4 arrived today and it works!
From flashing the previous one I noticed neither the K or M firmware looked as nice as the from-factory programmed firmware.  Is there any way to configure the open source firmware to have the same appearance?
Did the manufacturer create an in-house firmware just for this clone?  The open source ones did not even have the 180 degree rotation feature for the display,  which must mean either there is a third firmware out there that I've missed, or it's manufacturer modified.

Also, are there any PCB faults known with the LCR-T4 that can be improved upon?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 22, 2019, 02:47:01 pm
The manufacturer's firmware is a modified k-firmware which has a nice user interface but less functionality. More kBs for fancy graphics means less flash memory for features, it's a trade-off. The m-firmware supports a flipped display output for ST7565, but it's a compile time setting. I think, the k-firmware supports that also. AFAIK, the T4 has no issues besides a missing level shifter for the 3.3V display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on November 27, 2019, 04:39:31 pm
Hi, Madires

I am classifying SMD components and have noticed a failure in your firmware.
Observed in several components, a problem that does not occur with the K firmware, nor with the Chinese firmware that incorporates the
GM328 or LCR-T4 meters.

An example in photos with a transistor C5707 for the test, in the datasheet says that it is a NPN Bipolar transistor.

The original Chinese GM328 and LCR-T4 meters, and the GM328 with the K firmware, the transistor put it in position
that you put it tells you that it is a bipolar NPN transistor, and it appears as the datasheet says, everything is fine here.

Now the same transistor with the GM328 and with the firmware M, in one position it appears as a NPN Bipolar transistor, and in the other position it appears as a JFET, leading to error by not knowing positively what the component really is.

Look at the photos and look at the position of the transistor that is only rotated in the meter socket.

(https://i.ibb.co/rx7c6XQ/M1.jpg) (https://imgbb.com/)  (https://i.ibb.co/WzGLVNK/M2.jpg) (https://imgbb.com/)

The same applies to the double SOT23 three-pin encapsulated diodes, connected to the original Chinese GM328 and LCR-T4 or to the GM328 with the K firmware and appears as two diodes, either in series, opposed or as they are inside the component but always
It detects it as two diodes.

(https://i.ibb.co/nmLkr29/diodos-3-pin.png) (https://imgbb.com/)

With the firmware of yours, you connect the three pins and it appears as a single diode or as a JFET transistor and it costs you
much measurement and in some cases it gives error.

I tell you because I do not know if it is my problem and if it happens with other components, and if not, if this problem could be solved and corrected.

Thank you very much.
Cheers
Title: Re: $20 LCR ESR Transistor checker project
Post by: hpmaxim on November 27, 2019, 05:35:32 pm
Given that there seems to be an infinite number of variations on these units, is there a good guide as to which one to buy and/or where to buy it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 27, 2019, 06:55:49 pm
The original Chinese GM328 and LCR-T4 meters, and the GM328 with the K firmware, the transistor put it in position
that you put it tells you that it is a bipolar NPN transistor, and it appears as the datasheet says, everything is fine here.

Now the same transistor with the GM328 and with the firmware M, in one position it appears as a NPN Bipolar transistor, and in the other position it appears as a JFET, leading to error by not knowing positively what the component really is.

That's strange. I haven't seen that before.

The same applies to the double SOT23 three-pin encapsulated diodes, connected to the original Chinese GM328 and LCR-T4 or to the GM328 with the K firmware and appears as two diodes, either in series, opposed or as they are inside the component but always
It detects it as two diodes.

With the firmware of yours, you connect the three pins and it appears as a single diode or as a JFET transistor and it costs you
much measurement and in some cases it gives error.

I tried two diodes in all possible ways and can't reproduce that issue. Do you have different GM328s for k-firmware and m-firmware? If yes, maybe there's something wrong with the one running the m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 27, 2019, 07:03:18 pm
Given that there seems to be an infinite number of variations on these units, is there a good guide as to which one to buy and/or where to buy it?

Two pages back there's a link to an overview of different models. You can get the testers from all well known market places.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on November 27, 2019, 07:19:40 pm
I will continue to select components, if it happens again I will put photos for you to see.

Yes, I have a GM328 with firm K, another with firm M and another with Chinese firm.
I tried several times and it gave me that problem.
Tomorrow I do tests again and I also tell you if it can be with photos.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 27, 2019, 07:46:36 pm
Please flash the GM328 running m-firmware with k-firmware and try the same components to check if that GM328 has a hardware problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hpmaxim on November 28, 2019, 01:44:05 am
Given that there seems to be an infinite number of variations on these units, is there a good guide as to which one to buy and/or where to buy it?

Two pages back there's a link to an overview of different models. You can get the testers from all well known market places.

Thanks... other than the features is there a benefit to one versus another? 8 vs 16 MHz?  Accuracy? Etc?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 28, 2019, 03:16:31 am
the overview table shows the benefits you want. Don't bother with ones without a rotary encoder.

clock speed is configurable.

accuracy is determined by the sense resistors (0.1% is better) and the voltage reference, which is typically bad on the clones. upgrade to a 0.1% voltage regulator if you want accuracy.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on November 28, 2019, 06:11:51 pm
Please flash the GM328 running m-firmware with k-firmware and try the same components to check if that GM328 has a hardware problem.

Hi Madires.
Fixed issue, just had to reinstall firmware.
Sorry for the inconvenience.
Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hpmaxim on November 28, 2019, 10:04:01 pm
the overview table shows the benefits you want. Don't bother with ones without a rotary encoder.

clock speed is configurable.

accuracy is determined by the sense resistors (0.1% is better) and the voltage reference, which is typically bad on the clones. upgrade to a 0.1% voltage regulator if you want accuracy.

Looks like the one to get is either the GM328A or the LCR-TC1/T7 (can't tell what the difference is between the TC1 and T7 are).  The GM328A+ seems worse.  I don't really understand how they are using a 7805 on a 3.7/4.2V battery...

I like the extra voltage on the zener measurements on the TC1 and the internal battery, but it does seem to be lacking the rotary encoder and all the extra measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 29, 2019, 05:52:29 am
I don't really understand how they are using a 7805 on a 3.7/4.2V battery...

Step up converter I'd imagine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 30, 2019, 02:20:25 pm
I like the extra voltage on the zener measurements on the TC1 and the internal battery, but it does seem to be lacking the rotary encoder and all the extra measurements.

The TC1 (actually the whole TC family) has an additional MCU controlling power and the test button. To run k/m-firmware that additional MCU needs to be reprogrammed (https://github.com/atar-axis/tc1-u4) or replaced with a simple circuitry (TC1-Mod, see transistor tester repository). And the TC1 is also known for shorted MLCCs in the power supply section.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 30, 2019, 02:37:15 pm
I've received several requests to add support for the DHT11 and DHT22 (DHT21, DHT33, DHT44) sensors. The code is nearly done but I don't have any of those sensors for testing. So I'm looking for someone with DHTxx sensors who has some time and coding skills to help with testing and debugging. Alternatively, DHTxx samples would be also appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: capitainekurck on November 30, 2019, 04:48:36 pm
accuracy is determined by the sense resistors (0.1% is better) and the voltage reference, which is typically bad on the clones. upgrade to a 0.1% voltage regulator if you want accuracy.

Hi Madire

I got a LCR T7 and i wait for an hiland M644 because the T7 boot only when he want.
i think he voltage regulator is the tl431 who is 1%. What better regulator who can be use in place of the tl431, and what are the resistors to change for 0.1 %.
an other question are they more accuracy  with your firmware than the Chinese firmware ?
thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 30, 2019, 07:43:45 pm
The TL431 is used as voltage reference by several clones and a better one would be LM4040 for example. The critical resistors are the test resistors, i.e. 680 and 470k Ohms. Nearly all of the modified firmwares are based on the k-firmware and there isn't much difference in accuracy between k and m-firmware. What helps is a better voltage regulator (e.g. MCP1702) and low tolerance test resistors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 30, 2019, 08:28:29 pm
What better regulator who can be use in place of the tl431...

The answers to 90% of the questions in this thread are answered in the manual, which is mentioned hundreds of times. RTFM.
https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 01, 2019, 07:42:04 am
The answers to 90% of the questions in this thread are answered in the manual, which is mentioned hundreds of times. RTFM.
https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf
I would change your correct point somewhat - not 90% but 99%! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: capitainekurck on December 01, 2019, 06:05:41 pm
hi

yes i have read the manual. but in fact i want to know if there is better components to make the tc1 more accurate with the same pin out. the mcp1702 and the 7l05 don't have the same pinout and it not easy to to change it. idem for the tl341  and the lt1004. I m a beginner hobbyist  :-[
it s probably easier to use TO92 part than SMD to change them so it possible to bend pins to solder them in the right place.
if i change this 2 components is there other resistors or capacitors to change around them ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 01, 2019, 07:57:35 pm
don't have the same pinout and it not easy to to change it.
That's what wires are for. :) You can always just glue the part in somewhere.

I don't know what board you have, but the mcp1702 is a drop in replacement for a to92 78L05

You can throw away the TL431. Voltage reference is not needed with a precision regulator.

All of this has already been discussed. I recommend opening this thread in single page mode ('Print' button at the top) and using the find function with some strategic keywords. Or use google with the "site:https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project" parameter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: theleakydiode on December 02, 2019, 02:44:24 am
Anyone else experienced these needing constant recalibration? That little underscore after the screen text keeps reappearing, I recalibrate it but it eventually comes back after testing few things.

I've got one of those blue EZM electronics studio branded units with firmware 1.11k.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 02, 2019, 10:22:18 am
1.11k is quite old, Please update to 1.13k (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)).
Title: Re: $20 LCR ESR Transistor checker project
Post by: theleakydiode on December 02, 2019, 12:06:45 pm
Hi I don't have any way of doing this unfortunately, any ideas what would cause it in 1.11k?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 02, 2019, 02:13:08 pm
theleakydiode, how do you calibrate? From the function menu or pre-shorting 3 test contacts?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 02, 2019, 06:14:49 pm
I've received several requests to add support for the DHT11 and DHT22 (DHT21, DHT33, DHT44) sensors. The code is nearly done but I don't have any of those sensors for testing. So I'm looking for someone with DHTxx sensors who has some time and coding skills to help with testing and debugging. Alternatively, DHTxx samples would be also appreciated.

The code works well with the DHT11. Anyone with a DHT22 (RHT03, AM2302) or compatible sensor?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 02, 2019, 06:30:32 pm
Madires, Proteus has virtual DHT11-DHT22 sensors.
I can easily check their work on your fresh firmware. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: theleakydiode on December 02, 2019, 11:32:36 pm
theleakydiode, how do you calibrate? From the function menu or pre-shorting 3 test contacts?

Preshorting the 3 contacts, this meter doesn't appear to support any other functionality or menus. It doesn't even have the extra modes that some people with this meter have where you hold the test button down for several seconds.

What hardware do I need to flash the new firmware onto this thing? Bearing in mind I have absolutely no experience with coding or microcontrollers what so ever.

1.11k is quite old, Please update to 1.13k (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)).
What do I need to download from here? The tester looks like this, it actually has a socketed ATmega328 inside.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 03, 2019, 04:14:18 am
What hardware do I need to flash the new firmware

Step #1: learning to search. Extremely useful skill for finding stuff on the internet.

All of this has already been discussed. I recommend opening this thread in single page mode ('Print' button at the top) and using the find function with some strategic keywords. Or use google with the "site:https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project" parameter.
You might find things like this:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg810893/#msg810893

I have absolutely no experience with coding or microcontrollers what so ever.
Step #2: read the documentation
The answers to 90% of the questions in this thread are answered in the manual, which is mentioned hundreds of times. RTFM.
https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 03, 2019, 10:39:06 am
What do I need to download from here? The tester looks like this, it actually has a socketed ATmega328 inside.

You could try the precompiled firmware from the mega328_2X16_menu directory.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 03, 2019, 06:34:25 pm
Madires, Proteus has virtual DHT11-DHT22 sensors.
I can easily check their work on your fresh firmware. :)
Madires, it wasn 't quite easy in Proteus, but the DHT11 and DHT22 sensors work perfectly! :-+
Thanks!:)
Title: Re: $20 LCR ESR Transistor checker project
Post by: boffin on December 03, 2019, 07:20:52 pm
I've gone back a number of pages, but what I'm looking for isn't readily available.

Is there a (wiki??) page somewhere that says
"For this Chinese Unit - here are the compile options".

I've messed around with trying to get new firmware on an Aliexpress special, and while it's kind of working, it immediately shuts off
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 03, 2019, 08:37:03 pm
For the k-firmware there are precompiled firmwares for several clones and for the m-firmware settings for a few clones are listed in the Clones file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: theleakydiode on December 05, 2019, 07:19:52 am
What do I need to download from here? The tester looks like this, it actually has a socketed ATmega328 inside.

You could try the precompiled firmware from the mega328_2X16_menu directory.

Thanks, so this would definitely not brick or damage the meter?

What hardware do I need to flash the new firmware

Step #1: learning to search. Extremely useful skill for finding stuff on the internet.

All of this has already been discussed. I recommend opening this thread in single page mode ('Print' button at the top) and using the find function with some strategic keywords. Or use google with the "site:https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project" parameter.
You might find things like this:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg810893/#msg810893

I have absolutely no experience with coding or microcontrollers what so ever.
Step #2: read the documentation
The answers to 90% of the questions in this thread are answered in the manual, which is mentioned hundreds of times. RTFM.
https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf (https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf)


Tried that but haven't found the answer. All I need is something cheap that'll work to flash the thing using the USB port, afterwards I suspect it'll be thrown into a drawer and forgotten about.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 05, 2019, 08:19:08 am
 :-// the answer is right in the link I provided. It doesn't get much cheaper than $2.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 05, 2019, 10:17:56 am
You could try the precompiled firmware from the mega328_2X16_menu directory.

Thanks, so this would definitely not brick or damage the meter?

If your tester doesn't run with that version you can simply try another one. All those simple testers are based on the same design.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 05, 2019, 10:38:09 am
Tried that but haven't found the answer. All I need is something cheap that'll work to flash the thing using the USB port, afterwards I suspect it'll be thrown into a drawer and forgotten about.
This kit will be enough for most AVR programming tasks
1.https://www.aliexpress.com/item/32670511994.html?gps-id=pcDetailBottomMoreOtherSeller&scm=1007.13338.128125.0&scm_id=1007.13338.128125.0&scm-url=1007.13338.128125.0&pvid=91a0b4c5-3df0-448d-9040-87c97a2f91b2 (https://www.aliexpress.com/item/32670511994.html?gps-id=pcDetailBottomMoreOtherSeller&scm=1007.13338.128125.0&scm_id=1007.13338.128125.0&scm-url=1007.13338.128125.0&pvid=91a0b4c5-3df0-448d-9040-87c97a2f91b2)
2.https://www.aliexpress.com/item/32657285482.html?algo_pvid=f4024e68-3546-4128-b2d7-8d4035d2f71b&algo_expid=f4024e68-3546-4128-b2d7-8d4035d2f71b-4&btsid=6f587a24-586c-4004-8673-b962220c4831&ws_ab_test=searchweb0_0,searchweb201602_2,searchweb201603_55 (https://www.aliexpress.com/item/32657285482.html?algo_pvid=f4024e68-3546-4128-b2d7-8d4035d2f71b&algo_expid=f4024e68-3546-4128-b2d7-8d4035d2f71b-4&btsid=6f587a24-586c-4004-8673-b962220c4831&ws_ab_test=searchweb0_0,searchweb201602_2,searchweb201603_55)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ktgohdt125 on December 09, 2019, 03:25:41 am
carelessly hook up the LCT tester to an undischarged 3uf 250vac cap and the LCR meter can't be power up anymore...

any fix to this or I got a burn out  Atmega 3289P???
 :'( :'(


[attachimg=1]
attach a pic of my LCR meter with a suspected shorted smd fet/transistor... ( red circle )

any inputs are much appreciated...

thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 09, 2019, 11:17:53 am
Most likely a zapped ATmega328. The component in the red cycle is a TL431 which is used as 2.5V voltage reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ktgohdt125 on December 09, 2019, 02:55:28 pm
Most likely a zapped ATmega328. The component in the red cycle is a TL431 which is used as 2.5V voltage reference.

if i replace the 328chip, i need to flash it right?!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 09, 2019, 07:23:40 pm
Yes, and don't forget to set the fuse bytes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bingo600 on December 09, 2019, 08:50:20 pm
@madires

I need to update fw on my "Chinese M328-T3"
I was just checkking out the SVN repos & cloning via git  ;)

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=887176)

I have a few questions:

1:
Why is the T3_T4 several revisions back ?
Has it been abandoned , for the T4_v2 ?


mfg
Bingo  ;)

Hmm just found out the git repos lacks behind the svn repos (your latest fw is 1.34 in git)
Now i use svn - but still the T3/T4 is not at 811
svn://mikrocontroller.net/transistortester

I might be mixing the std fw (811) , and your 1.37m.
Will 1.37m work on a T3 ?  (provided i use the T3/T4 settings from the "Clones" ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 10, 2019, 11:05:00 am
Possibly a lapse. But you can use the Makefile from the subdir to compile the latest firmware. The mirror service was discontinued a while ago unfortunately, and therefore the mirror at github is outdated. 1.37m should run on a T3.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 13, 2019, 01:24:41 am
Hi,

Do you know what is the difference between the LCR ESR T7 and T7H ?



thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 13, 2019, 08:40:47 am
Andbro https://www.aliexpress.com/item/4000070087557.html?spm=a2g0o.productlist.0.0.612d41a6tP9lxL&algo_pvid=2a63d2c8-4ab7-40b8-a1e7-6ee7ce2bc4d9&algo_expid=2a63d2c8-4ab7-40b8-a1e7-6ee7ce2bc4d9-1&btsid=f5042911-91af-4695-b3db-3042377c3381&ws_ab_test=searchweb0_0,searchweb201602_3,searchweb201603_55 (https://www.aliexpress.com/item/4000070087557.html?spm=a2g0o.productlist.0.0.612d41a6tP9lxL&algo_pvid=2a63d2c8-4ab7-40b8-a1e7-6ee7ce2bc4d9&algo_expid=2a63d2c8-4ab7-40b8-a1e7-6ee7ce2bc4d9-1&btsid=f5042911-91af-4695-b3db-3042377c3381&ws_ab_test=searchweb0_0,searchweb201602_3,searchweb201603_55)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 13, 2019, 12:09:54 pm
Hi,

Sorry Indman, i don't see the difference between the T7 and T7H.
Does a firmware is available for the T7?


Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 13, 2019, 02:43:48 pm
The Chinese have several variants of the model T7- they use different displays. There are options with black and white screen, with color screen on ST7735 (14pin interface) and also screen on ST7735 (6pin interface). If you bought an option on 6pin, it is suitable for a firmware from TC-1, which was adapted by madires or the original firmware, a link to which I had previously offered.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on December 13, 2019, 09:49:20 pm

Or it's better to buy the TC1 than TC7 ?

Best regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: theleakydiode on December 16, 2019, 08:51:38 pm
Holy markup batman!
[attach=1]
A very reputable electronics retailer is flogging these testers for £50, doesn't even come with an enclosure!
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 17, 2019, 04:18:02 am
yup design looks the same. No open source attribution   :--
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 17, 2019, 11:14:59 am
Or it's better to buy the TC1 than TC7 ?

Beware of U4 and some poorly chosen components in the power supply section.
Title: Re: $20 LCR ESR Transistor checker project
Post by: brunosso on December 18, 2019, 10:08:35 pm
Hi to all!

I have this version of the Transistor Tester

(https://image.dhgate.com/webp/m/0x0/f2/albu/g9/M01/AC/58/rBVaVV1fsXOAYB6vAAQX8y6GFVQ347.jpg)

Could you please tell me wich version i need to flash?!

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 19, 2019, 10:21:17 am
k-firmware: try mega328_2X16_menu
m-firmware: change display to HD44780 4-bit parallel and try default settings
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 19, 2019, 04:51:43 pm
Still looking for xmas presents? I have one for you! And it's free. :)

v1.38m
- Optional rounding of temperature value for DS18B20 (UI_ROUND_DS18B20, suggested by Obelix2007@EEVblog).
- Support for DHT11, DHT22 and compatible sensors (SW_DHTXX, thanks to indman@EEVblog and Obelix2007@EEVblog for testing).
- Added two thin cyrillic fonts (Thanks to Andrey@EEVblog).
- Changed output of BJTs to show V_BE and hFE also in case of a B-E resistor. Adapted remote commands accordingly as well.
- Added alternative Czech texts and several fonts with Czech characters (thanks to Bohu).
- Added tools for monitoring R/C/L on probes #1 and #3 (SW_MONITOR_RL and SW_MONITOR_C, suggested by indman@EEVblog).
- Added option for trigger output for event counter (suggested by Bohu).
- Updated Czech texts (thanks to Bohu).
- Added option to disable hFE measurement with common collector circuit and Rl as base resistor (NO_HFE_C_RL) to cope with some testers (issue reported by Obelix2007@EEVblog).
- Added option to output Zener voltage in high resolution (ZENER_HIGH_RES, suggested by Andbro@EEVblog).
- Improved OneWire_Probes() to minimize misdetection.
- Updated Russian texts (thanks to indman@EEVblog).
- Updated Spanish texts (thanks to pepe10000@EEVblog).
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on December 21, 2019, 05:37:27 pm
Free? Priceless!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on December 23, 2019, 04:08:47 pm
Just got myself two "HILAND" transistor testers with the 644 chip. One to use and one for mucking programming around. Currently updated to 1-13k 809 because I found in the SVN sutable .hex and .eep files. This editing and "make files" thing is a bit beyond me.

Thus my question. In addition to adapting to firmware 1.38m the existing Windows programs (see Transistor Tester SVN - Folder "Messtechniker"), what else might be of interest?

The rotten bit here is that the RxD and TxD ports on the 644 PA are not easily accessible.  |O Some direct soldering to the 644PA chip :scared: (not much SMD soldering expertise here) will be required when wanting to use the external Windows software.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hpmaxim on December 25, 2019, 03:41:45 am
Dumb question, I've seen a lot of people talk about replacing the 680/470k resistors, or the TL431 or the voltage regulator to improve accuracy.  A resistor is a resistor.  It strikes me that the value of the resistance isn't that important, the main issue is KNOWING what the resistance is.  How hard would it be to measure the values and put them directly into the firmware rather than just assume they are the nominal value.  I looked through some code on github and it appears the resistance value is pre-defined in the header file, but only once not for each resistor.  :(  I'd think you could do the same with the TL431 and regulator.  The other thing that could be done would be to replace the resistor with two resistors in parallel (1M + 820k) and (1200 + 1500), which would give nearly the same values (you'd have to adjust obviously) but would likely reduce error by a factor of 4, particularly if you could bin one high resistor with a low resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 25, 2019, 08:44:20 am
Indeed you can specify your resistor and vref values explicitly in the config.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 25, 2019, 08:54:31 am
You can select three matching resistors for Rl (680\$\Omega\$) and Rh (470k\$\Omega\$) and update the default values in the header file. A single value for the test resistors Rl and Rh simplifies a lot of calculations and reduces flash usage. And you can also update the default voltage values for Vcc and the external 2.5V reference. The external voltage reference helps if you have an inaccurate voltage regulator. But with an accurate regulator like the MCP1702 the external reference is unnecessary.
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on December 25, 2019, 06:04:25 pm
 :wtf:Hi! Someone please know what firmware i need to use on this tester? I have 1.11k by now...
328p mcu, ams1117 5.0 voltage regulator, graphic display...
Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 25, 2019, 08:57:26 pm
The tester seems to be the standard design. Any idea about the LCD controller? Monochrome or color display?
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on December 25, 2019, 11:00:17 pm
Uhm, monochrome, i think that is a jlx 12864g, uc1701x driver
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 25, 2019, 11:37:09 pm
The ST7565 driver might work, possibly mega328_st7565.
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on December 26, 2019, 12:00:51 am
Thanks! I will try it!  :-+ :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: hpmaxim on December 26, 2019, 04:42:48 am
I assume ALL modern SMD film resistors are laser trimmed from the factory, and it's probably no harder to trim to 1% than 5%.  Not sure if its harder to trim to .1% or .01% -- although they certainly do charge more.  If we assume that if you buy X% resistors, they have a gaussian distribution with X% std deviation with a cut off at 1 standard deviation, I think you'd need to buy about 16-20 resistors to find 3 resistors within .1 * X% of each other.  Is my expected distribution reasonable?   Is there a certain level of accuracy beyond which you are limited by other factors? 

It's hard for me to understand why having multiple calibration values would be that painful for the code, but I'm not going to change the software.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pierreraymondrondelle on December 26, 2019, 11:46:15 am
Beware the temperature stability: precision resistors are in a range below 25 ppm/K. Standard ones are far above.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 26, 2019, 11:56:18 am
I assume ALL modern SMD film resistors are laser trimmed from the factory

AFAIK, thin film resistors are laser trimmed or etched. Thick film resistors are cheaper to produce (1 and 5% tolerance).

It's hard for me to understand why having multiple calibration values would be that painful for the code, but I'm not going to change the software.

But it would be the best way to understand the drawbacks. >:D
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 26, 2019, 07:01:29 pm
it's probably no harder to trim to 1% than 5%.

I would imagine that it works the same as in printing, photography, LCD display, chip fab etc.
To obtain a higher yield of low defect product, you have to produce more, and discard more, which drives up the price.

find 3 resistors within .1 * X% of each other.

By that logic you could use the cheapest carbon resistors.  But absolute value is not the only thing desired in resistors. For measurement, you also want consistency. Temperature stability, low drift, low noise etc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: SMDfan on December 28, 2019, 01:51:15 am

Mr. Clone Ttester(indman),

I came across your archive related to LCR ESR tester. I am also trying to build a tester of my own for hobby. Do you happen to have the source codes for these testers? Thanks

SMDfan





Hi,

Clone Ttester is a Russian who has made differents firmwares for many ESR. He has many model not included in MicroKontroller.net.
The problem, it's in Russian.

See the link: https://yadi.sk/d/yW8xa5NJgUo5z

Thanks

Hi! It is my archive.
As not only Russian-speaking people use this archive, I decided to add new firmwares from k-firmware in English for different clones.
In the next several days I will add archive thus, as shown in a screenshot. You monitor changes in archive.
If dear madires to me allows to use its work, I can add to archive new compiled firmwares UI_ENGLISH for m-firmware? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hpmaxim on January 02, 2020, 08:10:26 pm
So... I just replaced the 7550 with a MCP1702 and replaced the 680 and 470k resistors with 0.1%.


Only remaining thing to do is remove the TL431?  Its firmware 1.13k.  I only ask because the TL431 is very close to the socket for the Mega328.  I think it would be easy to remove but VERY hard to solder back in, at least using a soldering iron.  Do I need to reprogram the AVR or does it autodetect the presence of the 431?
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 03, 2020, 07:21:25 am
Your answer is in the readme file
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 03, 2020, 02:23:56 pm
Only remaining thing to do is remove the TL431?  Its firmware 1.13k.  I only ask because the TL431 is very close to the socket for the Mega328.  I think it would be easy to remove but VERY hard to solder back in, at least using a soldering iron.  Do I need to reprogram the AVR or does it autodetect the presence of the 431?

The k-firmware auto-detects the external 2.5V reference by default. IIRC, there's no configuration switch to disable the code for the external reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hpmaxim on January 03, 2020, 02:39:11 pm
The documentation I saw suggested that if the voltage reference was removed you should install a 47k resistor (R16) pull-up onto the cathode pin.  The board I have, has values but not component designators.  I suppose if this is the case an 0805 resistor could probably fit between the terminals, since I think one terminal of the TL431 is hooked to VCC.

Interestingly, from what I can tell the MCP1702 guarantees only 0.4% accuracy, whereas the LM4040A should be accurate to 0.1%, while the TL431 is accurate to 0.5-2% depending on which one is used.  I'm a little surprised why the LM4040A isn't recommended.  Unfortunately, the pinout appears to be different, and it seems to require a pull-up of ~39K.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on January 05, 2020, 10:29:59 am
I think it goes without saying that Chinese clones will come with the lowest grade reference.

You don't really need to know the R designator. As the readme says, if the program doesn't detect the missing reference, just increase the value of the pull-up resistor on pin PC4.

The LM4040 was mentioned a couple times in the readme, as well as other alternatives.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 05, 2020, 11:51:09 am
Interestingly, from what I can tell the MCP1702 guarantees only 0.4% accuracy, whereas the LM4040A should be accurate to 0.1%, while the TL431 is accurate to 0.5-2% depending on which one is used.

From testing different voltage references we found out that the external 2.5V reference needs to be about 10 times more accurate than the voltage regulator to provide a benefit. As an alternative you could measure Vcc with a proper bench DMM and adjust the configuration value accordingly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: daemon123 on January 06, 2020, 08:44:06 pm
No change, still dead slow

Code: [Select]
avrdude -c avrisp -b 19200 -p m328pb -P COM7 -U flash:w:TransistorTester.hex:a -U eeprom:w:TransistorTester.eep:a -v

avrdude: Version 6.3-20171130
         Copyright (c) 2000-2005 Brian Dean, [url]http://www.bdmicro.com/[/url]
         Copyright (c) 2007-2014 Joerg Wunsch

         System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr\bin\avrdude.conf"

         Using Port                    : COM7
         Using Programmer              : avrisp
         Overriding Baud Rate          : 19200
         AVR Part                      : ATmega328PB
         Chip Erase delay              : 9000 us
         PAGEL                         : PD7
         BS2                           : PC2
         RESET disposition             : dedicated
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
           flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
           lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
           signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

         Programmer Type : STK500
         Description     : Atmel AVR ISP
         Hardware Version: 2
         Firmware Version: 1.18
         Topcard         : Unknown
         Vtarget         : 0.0 V
         Varef           : 0.0 V
         Oscillator      : Off
         SCK period      : 0.1 us

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.05s

avrdude: Device signature = 0x1e9516 (probably m328pb)
avrdude: safemode: lfuse reads as E2
avrdude: safemode: hfuse reads as D9
avrdude: safemode: efuse reads as F4
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
         To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: reading input file "TransistorTester.hex"
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: writing flash (29732 bytes):

Writing | ################################################## | 100% 33.30s

avrdude: 29732 bytes of flash written
avrdude: verifying flash memory against TransistorTester.hex:
avrdude: load data flash data from input file TransistorTester.hex:
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: input file TransistorTester.hex contains 29732 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 19.14s

avrdude: verifying ...
avrdude: 29732 bytes of flash verified
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (857 bytes):

Writing | ################################################## | 100% 42.31s

avrdude: 857 bytes of eeprom written
avrdude: verifying eeprom memory against TransistorTester.eep:
avrdude: load data eeprom data from input file TransistorTester.eep:
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: input file TransistorTester.eep contains 857 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 3.46s

avrdude: verifying ...
avrdude: 857 bytes of eeprom verified

avrdude: safemode: lfuse reads as E2
avrdude: safemode: hfuse reads as D9
avrdude: safemode: efuse reads as F4
avrdude: safemode: Fuses OK (E:F4, H:D9, L:E2)

avrdude done.  Thank you.


will try to install another crystal tomorow,
could it be a bad chip ?
or the firmware is not for 8mhz ?

Referring to my old post, i got the LCR T4 working with m328pb. For some reason it was on clock failure detection swtching to 1mhz and i was unable to set the correct fuse to disable CFD.

Here are the correct fuses for ATmega 328pb
efuse = FC
hfuse = D9
lfuse = FF

the default avrdue.conf will not write the correct efuse FC
you have to modify the avrdude.conf

open it and ATmega328 look for 'memory "efuse"' section. It will look like below

Code: [Select]
    memory "efuse"
size = 1;
min_write_delay = 4500;
max_write_delay = 4500;
read = "0 1 0 1 0 0 0 0 0 0 0 0 1 0 0 0",
       "x x x x x x x x o o o o o o o o";

write = "1 0 1 0 1 1 0 0 1 0 1 0 0 1 0 0",
      "x x x x x x x x x x x x x i i i";
    ;


change

"x x x x x x x x x x x x x i i i"
Code: [Select]
write = "1 0 1 0 1 1 0 0 1 0 1 0 0 1 0 0",
      "x x x x x x x x x x x x x i i i";       



to

"x x x x x x x x x x x x i i i i"
Code: [Select]
write = "1 0 1 0 1 1 0 0 1 0 1 0 0 1 0 0",
      "x x x x x x x x x x x x i i i i";       


Save it, now u will be able to program the correct efuse FC.

Now i have some questions. Can i install rotary encoder in this variant ?
also is m-firmware (compiled) available for it ?

any other mods for it ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 07, 2020, 01:44:31 pm
Thanks for the hint! A rotary encoder should be possible (try PD1 and PD3), but you need to configure and compile the firmware for that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on January 07, 2020, 05:27:06 pm
"daemon123" example:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1090619/#msg1090619 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1090619/#msg1090619)

Greetings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on January 10, 2020, 11:47:10 pm
Hi,

I have a colour T7 model. It's the same model as the TC1, i think so. I have read the file in Clones in Markus firmware 1.38. My question is: is it possible to replace the firmware without removing the U4 Micro-controller STC15L104W ? My display has 6 pins.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 11, 2020, 11:31:06 am
You could reprogram U4 (https://github.com/atar-axis/tc1-u4). That firmware was tested with the TC-1 but I assume it should also work with with the other models.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on January 11, 2020, 09:38:00 pm
Hi,

When i "Make All" with WinAVR, i have this error. Firmware Markus for TC7.

main.c: In function 'CheckBattery':
main.c:1392:21: warning: unused variable 'Temp' [-Wunused-variable]

Thank for your help
Title: Re: $20 LCR ESR Transistor checker project
Post by: standal on January 11, 2020, 10:13:03 pm
Hello,
is it possible to use frequency counter on anothet input pin? PD4 is used at LCR-T4 as reset pin for display and therefore is not possible to use this feature. Can somebody modify m-firmware or tell what and how to modify? In source I have read that it has to be PD4.
Thanks
standal
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2020, 12:56:45 pm
When i "Make All" with WinAVR, i have this error. Firmware Markus for TC7.

main.c: In function 'CheckBattery':
main.c:1392:21: warning: unused variable 'Temp' [-Wunused-variable]

It's just a warning you can simply ignore. Will be fixed in the next firmware version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2020, 01:21:21 pm
is it possible to use frequency counter on anothet input pin? PD4 is used at LCR-T4 as reset pin for display and therefore is not possible to use this feature. Can somebody modify m-firmware or tell what and how to modify? In source I have read that it has to be PD4.

The frequency counter uses hardware timer #0 for counting pulses. Timer #0's fixed input is T0 which is PD4 (ATmega328). Your best bet is to disconnect the displays reset line from PD4, to use a pull-up resistor and cap to create a reset pulse and to disable LCD_RESET in the display's configuration.
Title: Re: $20 LCR ESR Transistor checker project
Post by: standal on January 12, 2020, 02:10:05 pm
Hi,
thank you for advice, but I wanted to avoid HW modifications. But would not be possible to use timer 1 (PD5)? This one is not used on the LCR-T4.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2020, 03:32:23 pm
Timer #1 is already used for the gate time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: standal on January 12, 2020, 04:40:31 pm
Hi,
and is not possible to use timer#0 for "the gate time" and than timer#1 for frequency counter?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2020, 05:16:52 pm
Timer #0 is an 8-bit timer, while Timer #1 is 16 bits. And the firmware doesn't have an abstraction layer to deal with multiple sources triggering the same interrupt.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alxtr1bal on January 29, 2020, 06:05:02 am
Hello everyone,

Has anyone succeeded in installing the latest 1.13k-firmware on the clone LCR-T7 (m324pa mcu)  ?

I modded the u4 firmware , and used the ST7735 Makefile, mcu = m644, compiles ok. Then i use my TL866 II programmer (fuses set there).
After upload on the device, start, the screens stays blank...

I would appreciate if someone could help me on this :-)

I managed to compile and install the 1.38m successfully, but i wanted to try the k one !

Thank you  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 29, 2020, 01:58:07 pm
Have you set "PARTNO = m324p" in the Makefile?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 29, 2020, 02:21:37 pm
Hello everyone,
Has anyone succeeded in installing the latest 1.13k-firmware on the clone LCR-T7 (m324pa mcu)  ?
Thank you  :)
K-firmware requires major changes to source files in order to customize firmware for clone LCR-T1 (T7). :( In m-firmware, this is done much easier and faster(thanks madires!)
Title: Re: $20 LCR ESR Transistor checker project
Post by: alxtr1bal on January 29, 2020, 07:34:22 pm
Have you set "PARTNO = m324p" in the Makefile?

Hello @madires, yep, but in config.h, it's considered like 644.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alxtr1bal on January 29, 2020, 07:35:20 pm
Hello everyone,
Has anyone succeeded in installing the latest 1.13k-firmware on the clone LCR-T7 (m324pa mcu)  ?
Thank you  :)
K-firmware requires major changes to source files in order to customize firmware for clone LCR-T1 (T7). :( In m-firmware, this is done much easier and faster(thanks madires!)

I think so too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 29, 2020, 09:05:45 pm
Have you set "PARTNO = m324p" in the Makefile?

Hello @madires, yep, but in config.h, it's considered like 644.

Does the tester stay powered on for a few seconds (backlight lit) after pushing the start/test button?
Title: Re: $20 LCR ESR Transistor checker project
Post by: alxtr1bal on January 30, 2020, 06:20:11 am
Have you set "PARTNO = m324p" in the Makefile?

Hello @madires, yep, but in config.h, it's considered like 644.

Does the tester stay powered on for a few seconds (backlight lit) after pushing the start/test button?

My last test (after playing with some defines) shows that the screens stays on, i can't power it off.

But i can remember that i had the screen stays on a few seconds yes... can't remember the defines... i did a lots of testing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 30, 2020, 12:35:00 pm
In that case there's something wrong with the pin assignment for the display signal lines.
Title: Re: $20 LCR ESR Transistor checker project
Post by: montyx on February 04, 2020, 08:53:46 pm
Hello guys!

I'd tried to read the whole topic, but it's not so easy to find the answer for my question. Which version is the most supported and best to buy from the Aliexpress vesion of the LCR testers?
- LCR T1-7
- LCR TC1
- LCR TC-T7H

Thanks in advance for every help
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 04, 2020, 09:31:59 pm
Those clones have an additional MCU for managing power and the test button. You would have to reprogram that MCU or replace it with a small circuit to be able to run the open source firmwares. There are also reports about hardware issues with the power circuitry, e.g. shorted MLCCs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: montyx on February 04, 2020, 11:09:42 pm
Thanks for the update. In that case which other device that you'd advice? There are many supported devices based on the SVN repo. If it's possible I try to keep the budget below $20  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2020, 01:57:01 pm
An AY-AT clone is still a good choice, and the Hiland M644 comes with several hardware options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on February 06, 2020, 02:44:32 pm
Hi,

Who could share the .HEX, .eep and Makefile files compiled Markus V1.38 for a TC7 or TC1.

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on February 06, 2020, 06:48:41 pm
Question after stupid mistake.
I have an DTU-1701 and was happy with it.
Programmed a few times new firmware with TL866ACS,
that worked fine.
Now I wanted to update the software and I've forgotten
to set the flags. Stupid me.
Programming went fine and the unit has the new software.
But it is extemely slow. I think the Xtal is switched of.
Problem now is, I can't reprogram, because my TL866ACS
doesn't see the chip. Can't read the chip ID and can't reprogram.

Please does anyone have an solution for me?
Thanks for reading first.

Is replace an new chip an option?
Have not much knowledge of microcontroller,
but replacing the chip I can.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 06, 2020, 09:30:44 pm
If the programmer can't read the chip ID anymore something went very wrong with the fuse bits. To recover the MCU you would need a programmer supporting the ATmega's HV programming mode. The other option is to replace the ATmega. with a new one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on February 06, 2020, 10:19:13 pm
Thanks for reply Madires.
A programmer with HV programming mode is not an option
I think. a. the price, b. the work c. can this be done in ICSP mode?
Thats no option
Yes, a new chip should be the option.
or, buy a new unit.
They cost not the price of a new car.

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 07, 2020, 06:34:01 am
Pukker, TL866A is a smart programmer that supports several programming modes, including HV.
Check again if the ICSP interface is connected correctly to the board and if the Vcc voltage is applied to the ATMega328?
You can remove the ATMega328 chip from the tester board and if you have a tqfp32 zif socket to DIP28 adapter, the TL866 can reset the fuse state to factory settings in HV mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on February 07, 2020, 01:41:03 pm
Hooray.
My DTU-1701 is working again.
Couldn't access with my TL866A programmer.
Thinking Pukker, once you bought an USBasp.
With Extreme Burner software, hardware setting: Speed 500hz,
programming went fine.
Why, I don't know, but it worked.
Tested again with TL866A and that is working OK.
Happy me.
Unit works fine.

Madires and Indman, thanks for thinking with me,
much appreciated.

Indman, tqfp32 zif socket to DIP28 adapter,
haha, maybe in spare for later. Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elf on February 09, 2020, 09:54:26 am
Hello guys!

I'd tried to read the whole topic, but it's not so easy to find the answer for my question. Which version is the most supported and best to buy from the Aliexpress vesion of the LCR testers?
- LCR T1-7
- LCR TC1
- LCR TC-T7H

Thanks in advance for every help

Chinese TC-1 works fine with that firmware but need some corrections. For correct operation also need reprogram U4 with this firmware: https://github.com/atar-axis/tc1-u4 or modify schematic, remove U4 completly and add two transistors instead. I can share my firmware
Modify message
Title: Re: $20 LCR ESR Transistor checker project
Post by: elf on February 09, 2020, 09:55:39 am
Hi,

Who could share the .HEX, .eep and Makefile files compiled Markus V1.38 for a TC7 or TC1.

Thank

I can share 1.34m .eep and .hex russian language. Some later i will try build 1.38 english.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 09, 2020, 12:18:55 pm
Hello guys!

I'd tried to read the whole topic, but it's not so easy to find the answer for my question. Which version is the most supported and best to buy from the Aliexpress vesion of the LCR testers?
- LCR T1-7
- LCR TC1
- LCR TC-T7H

I collected some more information about Chinese products:
So:
1. LCR-TC1 is a color TFT display with resolution of 160x128 pixels.
The processor is ATMega324, but newer models of this clone already use the ATMega644 processor. The factory original firmware can be replaced with an alternative m-firmware(madires).
2. LCR-T7 - there are variants of this clone with both colour TFT display and black and white. The display resolution can be different - 128x64 in black and white, 128x128 and 160x128 - in color.
The factory original firmware can be replaced with an alternative m-firmware so far only for displays with a 6-pin interface to the base board.
3.LCR-T7H is a 128x128 pixel color TFT display. The processor is ATMega644. The device circuit was slightly changed - the Chinese used the DC-DC variant on the MT3608 (B628x) chip instead of the transformer voltage https://www.olimex.com/Products/Breadboarding/BB-PWR-3608/resources/MT3608.pdf (https://www.olimex.com/Products/Breadboarding/BB-PWR-3608/resources/MT3608.pdf)
The new board modification was marked T7-Plus v0.1.
The photo of the board and the schematic diagram are provided by one of the participants Vrtp.ru the Russian-language forum, and are attached to my message. Clones of LCR-TC1 may be provided with the same modified boards. Please check with the seller for this information.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 09, 2020, 01:40:13 pm
Do you know the LCD controllers of the other displays used by the T7? The TC1's 160x128 color display is a ST7735.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 09, 2020, 01:57:07 pm
Bohu is working on adding more east European characters to all fonts based on ISO 8859-2. So we are looking for users from those countries who like to provide language specific texts in their mother tongue, i.e. Albanian, Hungarian, Polish, Slovak and so on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: montyx on February 09, 2020, 10:11:00 pm
Maybe I can help with the Hungarian language, if it's not a very huge project
Title: Re: $20 LCR ESR Transistor checker project
Post by: elf on February 10, 2020, 04:35:20 am
If anybody want 1.34m russian and 1.38m english firmware for chinese LCR-TC: https://yadi.sk/d/Ebxj49EvD5zmEg
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 10, 2020, 10:36:23 am
Maybe I can help with the Hungarian language, if it's not a very huge project

It's a tiny project. The first task is to take var_english.h and translate the text using the ISO 8859-2 character set. Later on when Bohu has done the fonts, the second task is to check if texts and characters are displayed correctly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: montyx on February 11, 2020, 10:34:32 am
Do you have any translating project, or just use the git for the updates?
Can you provide a link, where can I review the text files?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 11, 2020, 11:10:19 am
Please download the latest m-firmware (https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware), uncompress the archive, edit var_english.h (using the ISO 8859-2 character set), save it as var_<my language>.h and send me a copy. I'll add your var_<my language>.h to the source and send you a beta version for testing when Bohu has finished the fonts.

BTW, the languages covered by ISO 8859-2 (Latin-2) are:
- Albanian
- Bosnian
- Croatian
- Czech (done)
- German (done)
- Hungarian
- Polish (Jacon)
- Romanian (Dumidan)
- Serbian Latin
- Slovak
- Slovene
- Upper Sorbian
- Lower Sorbian
- Turkmen

I'll keep this list updated.

Update: Bohu has finished the fonts. So I'm waiting for your var_<my language>.h files. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: montyx on February 12, 2020, 07:09:31 pm
On the weekend, I'm going to check it :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on February 13, 2020, 12:35:34 pm
Hi,

After 245 pages, i'm asking to me again this question "Witch is the better ???"
You have the new T7H. Is it better than the TC1 end the T7. You have again the ST15F104W .........
Many talk about the Hiland M644 is the better.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 13, 2020, 02:48:26 pm
The Hiland M644 comes with the extended frequency counter (low frequency crystal, high frequency crystal, signal input without buffer) but skimps on bypass caps. The TC-x have a nice case with a LiPo battery. On the other side, there are several reports about shorted MLCCs and other issues in the power supply circuitry. My guess is that it depends on which components the manufacturer got from Shenzhen that day. No idea if the T7H has the same issues (no feedback yet). And of course, the ST15F104W is a nuisance. So neither tester is better, though you might prefer one over the other.
Title: Re: $20 LCR ESR Transistor checker project
Post by: junandaaa on February 15, 2020, 01:13:13 pm
heey thank you for shared the firmware eng 1.38, I also really need it too  :-+
btw can you teach me how to get eeprom files? I tried to make a file using winavr, but only got the hex file. how to get the eeprom file?
I want to learn hehe
Title: Re: $20 LCR ESR Transistor checker project
Post by: VEGETA on February 15, 2020, 08:08:09 pm
which one we should buy today? in order to get the best version ever and to get the good firmware
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 16, 2020, 05:25:08 pm
That question was answered already several times in the last few pages.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on February 20, 2020, 07:21:43 pm
Hi,

What is the best solution for T1 or T7?

Reprogram the U4 or modify the hardware ?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 20, 2020, 09:19:47 pm
Reprogramming U4 is less work, but the hardware mod has a lower quiescent current than U4.
Title: Re: $20 LCR ESR Transistor checker project
Post by: junandaaa on February 24, 2020, 10:35:30 pm
If anybody want 1.34m russian and 1.38m english firmware for chinese LCR-TC: https://yadi.sk/d/Ebxj49EvD5zmEg

sir, i have flashed the .hex and .eep file, but why does it not work properly? I only get a white screen when the pot is pressed, and when I release it off again. where is wrong? I use gm328
Btw sry for my english  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 25, 2020, 10:20:03 am
A firmware compiled for the TC-1 won't run on the GM328 (AY-AT clone) because the hardware differs. The settings for the AY-AT are listed in the Clones file. Apply those and compile the firmware. You could also try the precompiled firmwares from https://yadi.sk/d/yW8xa5NJgUo5z/GM328A.
Title: Re: $20 LCR ESR Transistor checker project
Post by: junandaaa on February 25, 2020, 04:32:45 pm
ohhh I think the file can also be used for gm328. is there a special way to compile the file? a few days ago I tried to compile it but only got the .hex file, and didn't get the .eep file
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 25, 2020, 06:00:27 pm
If you're using 'make' then the .eep file should be created also. If not, please check your IDE on how to integrate the Makefile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: aristarchus on February 26, 2020, 01:01:25 am
If you're using 'make' then the .eep file should be created also. If not, please check your IDE on how to integrate the Makefile.


Hi, just a quick question, the 'make' requires the sources, where are they? by looking at the yandex folders, they are not included.
Where/how can we get them?
Title: Re: $20 LCR ESR Transistor checker project
Post by: flywheelz on February 26, 2020, 01:37:00 am
If you're using 'make' then the .eep file should be created also. If not, please check your IDE on how to integrate the Makefile.


Hi, just a quick question, the 'make' requires the sources, where are they? by looking at the yandex folders, they are not included.
Where/how can we get them?

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/)

or

https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware (https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware)
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on February 29, 2020, 01:50:44 pm
:wtf:Hi! Someone please know what firmware i need to use on this tester? I have 1.11k by now...
328p mcu, ams1117 5.0 voltage regulator, graphic display...
Thanks!
I've tryed the mega328_st7565 firmware file, but the display or remain blank or become all black then become blank. When the button is pressed the backlight light up, after near 20s turn off as it should. After searching seem that the st7565 must be ok for this lcd, so why it not work? Thanks!

Forgot. The display is jlx 12864g. From a search the driver seem an st7565r.
Also, the fuse how must be set?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 29, 2020, 07:46:56 pm
Do you remember the model name of your tester?
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on February 29, 2020, 08:12:24 pm
Uh found an old mail dated 2016 calling it an "m328 transistor tester". Searching on the web there are with the same name also testers with a rotary encoder. Mine not have it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 29, 2020, 09:49:00 pm
Maybe that model uses a non-standard pin assignment for the display? Another issue could be the default contrast value.
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on February 29, 2020, 10:08:35 pm
Need to check. But as i'v always a lot of luck, i'm sure that's all non standard  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on March 01, 2020, 08:52:56 am
I've done a quick test connecting a logic analyzer and for sure on lcd pins i get clock, cs and data. Now i check on what pins the lcd goes.
EDIT:
Backlight to vcc
Sclk pin 32 - PD2 (INT0/PCINT18)
Sda pin 31 - PD1 (TXD/PCINT17)
Rs pin 1 - PD3 (PCINT19/OC2B/INT1)
Reset pin 2 - PD4 (PCINT20/XCK/T0)
Cs to gnd

From what i see from the logic analyzer, seem that the sda pin from the mcu goes to the rs pin. So i'm quite sure that the pinout from mcu is customized. Clock is ok.
Need to find a schematic for a 12864 display to check the pins. And maybe worth checking also the other pins :(

The attached schematic it's a standard one for 128x64 spi display? Thanks!

Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on March 01, 2020, 10:51:10 am
Connected as per schematic. Now the display can be read, but the contrast is wrong, and the graphic is flipped... for what it cost, i have to throw it away and buy a standard one  |O
As per image. Flipped, with wrong contrast, and also the first columns are missing

Edit: contrast fixed, had to reroute another pin to enable menu navigation. Remain the display flipped.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 01, 2020, 11:48:27 am
You can change the contrast, flip the display output and set the offset by changing some settings (see Makefile for the k-firmware). No need to get a new display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on March 01, 2020, 11:52:19 am
Need to know how to set the development enviroment in my windows 10 x64...
Nevermind, installing atmel studio. Only programmed pic in past, so i'm a newbie with avr :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 01, 2020, 12:49:05 pm
EDIT:
Backlight to vcc
Sclk pin 32 - PD2 (INT0/PCINT18)
Sda pin 31 - PD1 (TXD/PCINT17)
Rs pin 1 - PD3 (PCINT19/OC2B/INT1)
Reset pin 2 - PD4 (PCINT20/XCK/T0)
Cs to gnd
This display circuit corresponds to the known clone circuit LCR-T4 StripGrid! Try using firmware files from the "mega328_T3_T4_st7565" folder. If the image is reversed, I can help you rotate and adjust offset.
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on March 01, 2020, 01:12:23 pm
EDIT:
Backlight to vcc
Sclk pin 32 - PD2 (INT0/PCINT18)
Sda pin 31 - PD1 (TXD/PCINT17)
Rs pin 1 - PD3 (PCINT19/OC2B/INT1)
Reset pin 2 - PD4 (PCINT20/XCK/T0)
Cs to gnd
This display circuit corresponds to the known clone circuit LCR-T4 StripGrid! Try using firmware files from the "mega328_T3_T4_st7565" folder. If the image is reversed, I can help you rotate and adjust offset.
Thanks! But... Too late  :scared: Already rerouted the traces to correct pins. Now i'm installing the avr studio for fix the flipped image. Another thing: The trace that goes normally to pd7, was going to pd0.
If only i knew that i had the need to recompile it anyway (for flipped screen), i could have avoided to reroute the pins  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on March 01, 2020, 03:38:49 pm
Recompiling done. Now it's ok.
But, why at the end of the selftest it give the 1.13k version? I've loaded the main.c at https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/main.c (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/main.c) and used my own makefile with correct mods.
And, it's normal that if i not put a component to test, after the warning that there isn't a component, show that it's not calibrated, but i've done several times the calibration process? EDIT: This only happens if i test something between pin 1-2 after have tested something on pins 1-3
Thanks!

EDIT- Maybe i've understood. The precompiled versions are only for the "k" branch, while the updates of the "m" versions are at https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)
But i'm having problems compiling them, or better, in the makefile there aren't options for set for example the display type, etc.

RE-EDIT
Whoaaaaaa, not so easy, found config.h and config-328.h files, all done. Something to note:
-Little problem, also with contrast 0 the contrast it's a bit too high (really different scale from the k version).
-The calibration procedure doesn't take anymore in account the capacitor test (by design)
-For enter in the menu had the need to add the option for the 3pin short, else i wasn't unable to enter like in the k version longpressing the button
-the tester loop continuously also when has found the component (i think that is by design)

At the end of all, i think that i stik with 1.13k...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2020, 11:08:52 am
Please read the m-firmware's README file. ;) It explains all things you want to know.
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on March 02, 2020, 11:54:32 am
I've updated to v1.38m

I'm getting 7pf cap reading on leads 1 and 2. Did a self test which fixes it(no component found) but getting 7pf reading again when I switch off/on device.
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterx81 on March 02, 2020, 12:23:18 pm
You need to save after the self test
Title: Re: $20 LCR ESR Transistor checker project
Post by: broadway on March 03, 2020, 06:25:27 pm
 Thank you. It worked.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 14, 2020, 01:30:48 pm
A reminder on the call for localized texts based on ISO 8859-2. If you like to support the project by translating the firmware texts to a language covered by ISO 8859-2 please see https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2913368/#msg2913368 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2913368/#msg2913368) for details.
Title: Re: $20 LCR ESR Transistor checker project
Post by: powersola on March 16, 2020, 04:56:38 pm
Hi all,

maybe I can ask for your help.

I tried to compile the 1.38m firmware for my AY-AT clone (marked Geekteches GM328A).
The file I get compiling under linux with avr-gcc 9.2.0 is "Program:   37020 bytes (113.0% Full)"
I see it's a toolchain problem, and tried even with a windows VM via WinAVR and the toolchains suggested somewhere in the thread extracted in the WinAVR folder (3.4.5.30, 3.4.4.24, for example) but the less I can get is somewhere 105.x%.

May I ask if somebody of you that have 5 minutes of spare time can try, under a known previously working environment, to compile my files that I attach? Or I messed something in config, or my environment is not set up in the right way.

Thank you,
Powersola
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 16, 2020, 05:34:00 pm
With avr-gcc 5.4.0 and your config.h I get 105% too. Try to disable some feature you don't need, e.g. SW_DS18B20, SW_DHTXX and SW_UJT.
Title: Re: $20 LCR ESR Transistor checker project
Post by: powersola on March 16, 2020, 06:10:13 pm
Thank you for the feedback!

I'm going to try again disabling something and I'll try again.
Good work, thanks so much.

Edit: Tried removing DS probes, onewire and UJT and reached 98.something %. Success!

I get blank screen on the tester, but it's the first compilation of this firmware from scratch so I think I picked some wrong choice in config files... I put on Atmega the precompiled 1.37m i found here some pages back that works, and I'll retry again someday with compilation.

EditEdit: Got 1.38 running, had just to fix some display parameters that were wrong. Great!

Powersola
Title: Re: $20 LCR ESR Transistor checker project
Post by: tooki on March 24, 2020, 12:22:23 pm
Hey everyone!

To those with an AY-AT or clone (i.e. color TFT version), could somebody measure how much current it draws in operation?

Thank you!


(Background: At my work (where I am interning before starting an apprenticeship as an electronics technician in the fall), one project we are working on (to be mechanical construction practice for the electronics apprentices, and design practice for the design engineering apprentices) is to use off-the-shelf AY-AT kits (but populated with the correct voltage reference and 0.1% resistors) and build a custom housing around it, with added banana jacks and SMT pad area. Since this model supports square wave output, and thus might be used for far longer periods of time than when testing components, I proposed that we power it from 6 AA batteries instead of a 9V block, since the AA's are far more cost-effective on a Wh basis. But since that also makes it bulkier, I figured I'd try and find out how much power it actually consumes.)

If anyone has suggestions or feedback on this plan, feel free to chime in! I'm still working my way through this whole thread…  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2020, 12:48:18 pm
I don't have any AY-AT clone but my guess would be between 20 and 30mA on average.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 24, 2020, 03:02:27 pm
Yes, here is a picture of the DTU-1701, you can see J6 goes to the MCU which is different to the Bside ESR02.
I think these are a cheap clone to be honest, it was only £16.
DTU-1701
I bought himself DTU-1701. I painted a complete schematic diagram
https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Schematic%20diagram (https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Schematic%20diagram)
Red color means changes made to the scheme:
1. Replace the frail  7150 on the LP2950-5.0(better MCP1702-5.0)
2. Replace  TL431 on LM4040A (R2A)
3. Added ceramics capacitors 10mkF on LP2950 input  and Vcc processor(pins 4-6)
4. Control divider resistors R21-R22 for voltage replaced 47kOm, control point moved to the collector Q2 (optional).
5. Capacitor C10 deleted - normal work without it.
6. Replace quartz at 16MHz (optional).
Revision board 3.1 - changes in comparison with earlier BSideESR02 virtually none except for a correct wiring ICSP connections-now all your contacts conveniently separated by the connector. Photo board to upgrade and after it will be lower.

Firmware:
New English and Russian k-firmware revision 813 for this clone  https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Firmware/Karl-Heinz%20K%C3%BCbbeler%20 (https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Firmware/Karl-Heinz%20K%C3%BCbbeler%20)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tooki on March 24, 2020, 03:59:02 pm
I don't have any AY-AT clone but my guess would be between 20 and 30mA on average.
Well that's the thing, we want to know actual measured current draw, not guesses. (I have an LCR-T4, but since the AY-AT uses a TFT, their current draw will not be comparable.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: blurpy on March 24, 2020, 06:05:27 pm
Quote
To those with an AY-AT or clone (i.e. color TFT version), could somebody measure how much current it draws in operation?

My AY-AT uses about 27mA during component testing. With short spikes up to 30mA, and about 23mA during frequency generation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2020, 06:33:50 pm
Now I can claim that it was an educated guess. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 24, 2020, 08:23:37 pm
Hey everyone!
To those with an AY-AT or clone (i.e. color TFT version), could somebody measure how much current it draws in operation?
Those with a dim screen on the AY-AT
In the power supply circuit of the screen backlite there are as many as two current-heating resistors in series 220 ohms and the amount 440 ohms
One stands on the red board (I replaced it with a short jumper).
The second one is on a board with a display.
For normal visibility of the screen it was necessary to change it to 100 ohm resistor.
The consumption of current on the battery became 47mA screen is perfectly visible. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnobarEl on March 25, 2020, 10:01:36 am
Hello all,

I'm thinking about buying one of those transistors tests. Before I made the purchase I decided to make a quick search on google, just out of curiosity and I find out this huge community. It blows my mind all the discussion related with this simple device. I thought they were all the same and I now know there are a lot of form factors, firmware...

Well, the point is, I tried to read it all but in the end I couldn't get a proper reply. Can some help me to choose the most valuable device?
All the suggestions are welcome!

Please, don't reply to me, "that has been answer before." I read it all but I couldn't decide.

Thanks for your help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 25, 2020, 11:05:46 am
If you prefer a basic model choose an AY-AT clone. For Zener check and extended frequency counter get a Hiland M664. For a nice case, LiPo battery, IR receiver and Zener check a TC-1 (or another model with the same case). There's no perfect tester model unless you build one yourself. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnobarEl on March 25, 2020, 11:15:52 am
Hi, thanks for your advice! That really helped me a lot. Its easier for me to study the differences between them and decide for one. In the end, I think I will be happy with any choice.

One more question. Can I use the "oficial" firmware in any of those products? Or should I have something in attention when I buy it to be able to update the firmware in the future?

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 25, 2020, 12:36:44 pm
Basically the OSHW firmwares (k & m) should run on all testers. One special case is the TC-1 (and family) with a management MCU. But we have an alternative firmware for that MCU to make the tester compatible, and also a small circuit to replace the MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnobarEl on March 25, 2020, 04:00:01 pm
That's great!

Thanks for your great support. I'm sure that your clear answer will be helpful for other as well.

Thanks!

Best Regards,
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 27, 2020, 08:07:48 pm

We all need some good news. The new m-firmware version is here!

v1.39m:
- Added Polish texts based on ISO 8859-2 (Thanks to Jacon).
- Fixed issue with preprocessor macro in SPI.c and syntax error in ADS7843.c  (reported by Bohu).
- Added option to store firmware data to Flash instead of EEPROM (DATA_FLASH, suggested by Vitaliy).
- Renamed cyrillic fonts to "win1251" and replaced Czech fonts with ISO8859-2 fonts provided by Bohu.
- Display of font for test purposes (SW_FONT_TEST).
- OneWire scan tool for listing ROM codes of connected devices (SW_ONEWIRE_SCAN).
- Option for probe-pair specific resistance offset (R_MULTIOFFSET, suggested by Vitaliy).

Available at https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tooki on March 29, 2020, 08:27:30 pm
Quote
To those with an AY-AT or clone (i.e. color TFT version), could somebody measure how much current it draws in operation?

My AY-AT uses about 27mA during component testing. With short spikes up to 30mA, and about 23mA during frequency generation.
Awesome, thank you so much!

Hey everyone!
To those with an AY-AT or clone (i.e. color TFT version), could somebody measure how much current it draws in operation?
Those with a dim screen on the AY-AT
In the power supply circuit of the screen backlite there are as many as two current-heating resistors in series 220 ohms and the amount 440 ohms
One stands on the red board (I replaced it with a short jumper).
The second one is on a board with a display.
For normal visibility of the screen it was necessary to change it to 100 ohm resistor.
The consumption of current on the battery became 47mA screen is perfectly visible. :)
Great info, thank you as well!


Much appreciated, guys! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on March 30, 2020, 01:21:12 pm
Yes, here is a picture of the DTU-1701, you can see J6 goes to the MCU which is different to the Bside ESR02.
I think these are a cheap clone to be honest, it was only £16.
DTU-1701
I bought himself DTU-1701. I painted a complete schematic diagram
https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Schematic%20diagram (https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Schematic%20diagram)
Red color means changes made to the scheme:
1. Replace the frail  7150 on the LP2950-5.0(better MCP1702-5.0)
2. Replace  TL431 on LM4040A (R2A)
3. Added ceramics capacitors 10mkF on LP2950 input  and Vcc processor(pins 4-6)
4. Control divider resistors R21-R22 for voltage replaced 47kOm, control point moved to the collector Q2. (optional).
5. Capacitors C10 deleted - normal work without it.
6. Replace quartz at 16MHz (optional).
Audit board 3.1 - changes in comparison with earlier BSideESR02 virtually none except for a correct wiring ICSP connections-now all your contacts conveniently separated by the connector. Photo board to rework and after it will be lower.

Firmware:
New English and Russian k-firmware revision 813 for this clone  https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Firmware/Karl-Heinz%20K%C3%BCbbeler%20 (https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Firmware/Karl-Heinz%20K%C3%BCbbeler%20)

Thanks Indman for sharing the upgrading modifications.
I ordered 100 pcs 470k and 680 smd resistors, format 1206, sorted and paired them with my Fluke and replaced the original ones
which had a lot of deviation. After selfcheck / calibration the measurement was improved.
Mentioning that calibration done with battery power, not the same is when working with an adapter.
Calibrate with the powersource wich you want to use.
Thanks for compiling the software. In version 8.13 it shows DC_Power_txt or something, when powered with an adapter,
translation not correct. Battery Power is indicated OK.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 30, 2020, 02:07:29 pm
In version 8.13 it shows DC_Power_txt or something, when powered with an adapter,
translation not correct. Battery Power is indicated OK.

Yes, this is my mistake when compiling English firmware. I fixed, now the DC Power Mode is displayed correctly.  :)
https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Firmware/Karl-Heinz%20K%C3%BCbbeler%20/English
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on March 30, 2020, 03:05:47 pm
In version 8.13 it shows DC_Power_txt or something, when powered with an adapter,
translation not correct. Battery Power is indicated OK.

Yes, this is my mistake when compiling English firmware. I fixed, now the DC Power Mode is displayed correctly.  :)
https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Firmware/Karl-Heinz%20K%C3%BCbbeler%20/English
Wow, that is superspeed service. Thanks.

Edit:
Tested, works fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on March 31, 2020, 08:49:44 pm
Meter "Not calibrated"

When I do selftest with my DTU-1701,
working OK. I calibrate with use of short testleads,
because in real life, mostly I use the testleads.
0.1ohm resistor reads 0.11.
Very good, resistor measurement in that range is not easy.
Even an good multimeter can't do that.

Strange, when I use the same resistor without testlead,
but directly on the clamps on the meter, it says 0.0ohm.
Ok, missing the testleads, that is OK.

But, the meter says directly "Not Calibrated".
Looks like the meter sees negative resistance and "resets calibration"
Tested this over again and calibration lost again.
Now I know, no problem, but want to tell this strange behaviour.

I hope this is not mentioned before, I follow this forum for long time,
but can't remember what is written in 247 pages.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Gandalf_Sr on April 01, 2020, 01:30:48 am
So I just ordered some LCR Research Pro 1 Plus tweezers for $300 but I own several of these $20 testers.

If someone (maybe me) was to turn the $20 tester circuit into a small PCB with a small OLED display, couldn't the Madires code be modified to run some pretty good tweezers?

I searched this thread for "tweezers" but the only hits I got were from 2017.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 01, 2020, 08:43:15 am
Meter "Not calibrated"
But, the meter says directly "Not Calibrated".
Looks like the meter sees negative resistance and "resets calibration"
Tested this over again and calibration lost again.
Now I know, no problem, but want to tell this strange behaviour.

That's right, Karl-Heinz mentions this in detail in his manual on page 116 in section 5.5 SelfTest Function:
"Before the test steps begin, the zero resistance of the connected probes
is determined for all three combinations (T1:T3, T2:T3 and T1:T2). This zero resistances will be
subtracted for the future ESR and resistance measurements below 10Ω. Only zero resistance values
below 0.90Ω are accepted, because this correction values are not uses for measurement of resistor
values above 10Ω. If you use cables for measurement, you should only take cables with low resistance
values. If the later measured resistance results fall below the particular zero resistance for more than
0.2Ω, the tester will be resetted to ”uncalibrated”.
Madires in the m-firmware provided this option and made it possible to save and load 2 different calibration profiles.
For internal and external test contacts, which is very convenient to use. There is no need to carry out a new calibration every time.
 :)  For k-firmware there is no such possibility yet.

If someone (maybe me) was to turn the $20 tester circuit into a small PCB with a small OLED display, couldn't the Madires code be modified to run some pretty good tweezers?

Would you like to have such a tester device as in this video, I understand correctly? :D
https://www.youtube.com/watch?v=1-_l4gSIHNM (https://www.youtube.com/watch?v=1-_l4gSIHNM)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vivaT on April 01, 2020, 11:33:28 am
i made these tweezers for 2 pin devices, very light and nice for smd stuff.
the font is a little small for this type of application, ideally it would have two kinds of font to improve the readability but thats a bit beyond my coding level.
If theres interested ill post pcb, bom ect
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 01, 2020, 12:39:37 pm
Nice DIY tweezers! Bonus points for the m-firmware. ;D BTW, there's a thread for pictures of DIY testers, cases and mods: https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/ (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vivaT on April 01, 2020, 12:57:28 pm
I haven't seen that post, great link madires! Posting more build pics over there :-+  Thanks for all your hard work on the firmware, you rock !
Title: Re: $20 LCR ESR Transistor checker project
Post by: avr on April 06, 2020, 11:57:41 am
Hello

I have this transistor tester:
(https://lh3.googleusercontent.com/proxy/hposJk5L2nJx1AhOlFREjSi7atYMCcN328buIBsW7EfHWlufD3Adl0fFDgmkw2IYNp8zK7SyRx5QUWuoyjAyTCqOcKQBektRocB2T9k)

and when I proceed to update to 1.13k version, I found that the screen text is rotated 90°. The remaining features of the device are OK. I used the files from the ST7735 folder, I have tested firmwares from other folders, but they don't work.

Also, I have tried to compile with Winavr the makefile in order to change by myself the screen orientation but I only get compiling errors (something related with a .elf file).

Could you tell me if there is firmware version for this device with screen in correct orientation?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 06, 2020, 12:23:21 pm
avr look folder https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_color_kit/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: avr on April 06, 2020, 02:47:27 pm
Hello

I have tried with that firmware yesterday and it did not work well. But today I have download the firmwares from the web again and now it is working flawlessly. Probably yesterday I made a mistake. Anyway the device is working now with version 1.13k. So, it is solved.

Thank you for your help :-+

Title: Re: $20 LCR ESR Transistor checker project
Post by: blurpy on April 08, 2020, 10:04:56 am
I replaced the 7550 regulator in my ST7565 kit tester with a MCP1702 precision regulator, which is more precise than the included TL431 reference.

What should I do now? Remove the 431? disconnect pin PC4 altogether? Or is it enough just to change config.h

EDIT: I just found this in the manual: "If you don’t install the precision voltage reference and you don’t add the relay extension, you should install a pull up resistor R16 to PC4 with a higher resistance value (47k?). This helps the software to detect the missing voltage reference."

Yep, the firmware measures the voltage at PC4 and if it's around 2.5V it assumes it's the external voltage reference. The pull-up resistor makes sure that PC4 is outside the expected voltage range, and 100k or 220k would be fine also. The m-firmware behaves the same way, but HW_REF25 (config.h) controls if the code get's included or not.

I have an AY-AT I would like to improve with the suggestions in this thread.

* 16MHz crystal
* 0.1% probing resistors - 680r and 470k
* MCP1702 instead of HT7550 voltage regulator
* m-firmware

From my understanding, the MCP1702 is pin compatible with the HT7550 so I can just replace that easily.

The consequences of this change seem to be:

1. I can remove the TL431 voltage reference
2. I need to disable HW_REF25 in the m-firmware
3. I have to change R16 from 2k2 to 47k?

Is this correct?
I'm confused about #3, because there is no mention of this in the README of the m-firmware, but it is in the k-firmware. Is it just a missing step in the m-firmware README, or does it no longer apply?

Relevant part of the m-README:

Quote
The external 2.5V voltage reference should be only enabled if it's at least 10 times more precise than the voltage regulator. Otherwise it would make the results worse. If you're using a MCP1702 with a typical tolerance of 0.4% as voltage regulator you really don't need a 2.5V voltage reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 08, 2020, 01:19:14 pm
1. I can remove the TL431 voltage reference
2. I need to disable HW_REF25 in the m-firmware
3. I have to change R16 from 2k2 to 47k?

Is this correct?
I'm confused about #3, because there is no mention of this in the README of the m-firmware, but it is in the k-firmware. Is it just a missing step in the m-firmware README, or does it no longer apply?

For running the m-firmware you can skip step #3 or remove R16 (no need to replace it). When HW_REF25 is disabled (default setting) the firmware will ignore any external voltage reference. The k-firmware handles external references a little different and always checks for a 2.5V reference (no setting to disable that). Therefore the k-firmware needs the resistor mod (step #3) to make it believe that there isn't any reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: blurpy on April 08, 2020, 01:34:48 pm
For running the m-firmware you can skip step #3 or remove R16 (no need to replace it). When HW_REF25 is disabled (default setting) the firmware will ignore any external voltage reference. The k-firmware handles external references a little different and always checks for a 2.5V reference (no setting to disable that). Therefore the k-firmware needs the resistor mod (step #3) to make it believe that there isn't any reference.

Thanks madires! I'll just remove R16 then.
Title: Re: $20 LCR ESR Transistor checker project
Post by: blurpy on April 12, 2020, 04:40:55 pm
Having spent so much time reading in order to understand how to upgrade and flash my AY-AT transistor tester I decided to document as much as possible of what I've learned: https://github.com/blurpy/transistor-tester

Maybe someone else will find it useful :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2020, 05:16:55 pm
I'm sure your documentation will help some users. The development of the k-firmware is on hold at the moment because of personal reasons, but that may change in the future.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on April 13, 2020, 06:55:15 am
Nice writeup blurpy, a concise howto like that is a nice addition!
Don't forget to add information about the calibration of the device at the end too!
Title: Re: $20 LCR ESR Transistor checker project
Post by: blurpy on April 13, 2020, 08:36:24 am
I'm sure your documentation will help some users. The development of the k-firmware is on hold at the moment because of personal reasons, but that may change in the future.

Ah, didn't know that. I've updated my wording.

Nice writeup blurpy, a concise howto like that is a nice addition!
Don't forget to add information about the calibration of the device at the end too!

Thanks! Good point. I think the readme explains it pretty well so I just added a short note about it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: panoss on April 20, 2020, 12:22:29 pm
Hi guys.
I 'm thinking of building this version of the transistortester (from here (https://github.com/svn2github/transistortester/blob/4ffb71857a2ddefac4bcd8377379204425b2c003/Doku/trunk/pdftex/english/ttester.pdf)):
[attach=2]

Instead of the LT1004 can I use a TL431 as a voltage reference? Like this:
[attach=1]
(from page 19 of the datasheet (http://www.ti.com/lit/ds/symlink/tl431.pdf?))
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 20, 2020, 12:31:14 pm
Yes, but you don't need it when using a MCP1702 voltage regulator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: panoss on April 20, 2020, 03:20:18 pm
The Vcc will be produced by an SX1308 (boost converter) if I make it battery operated.
Otherwise, I will use an LM7805.
Vcc is 5V, right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 20, 2020, 04:01:13 pm
Yep, 5V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: zape on April 24, 2020, 06:36:22 am
An AY-AT clone is still a good choice, and the Hiland M644 comes with several hardware options.

what about this one?
Will it work with open source firmware?
https://www.aliexpress.com/item/32643558421.html (https://www.aliexpress.com/item/32643558421.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 24, 2020, 10:12:01 am
That's an AY-AT which works fine with both OSHW firmwares (k: mega328_color_kit, m: see Clones file).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on April 28, 2020, 03:35:56 pm
Having spent so much time reading in order to understand how to upgrade and flash my AY-AT transistor tester I decided to document as much as possible of what I've learned: https://github.com/blurpy/transistor-tester (https://github.com/blurpy/transistor-tester)

Maybe someone else will find it useful :)
I'm sure your documentation will help some users. The development of the k-firmware is on hold at the moment because of personal reasons, but that may change in the future.
So, each time I want to flash my transistor tester it feels like I am trying to learn a foreign language from scratch :D
Specifically I am always super confused about which firmware gets uploaded where.
If (and that is a big if!) I get it right as of now the latest k-firmware is at revision 798
And the latest m-firmware is at revision 815
But then the links that blurpy provided in his writeup below are wrong?

Quote
The k-firmware source is available here (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/), with precompiled firmware for the AY-AT in the mega328_color_kit directory. There is also a Makefile there with the correct parameters. The source of the m-firmware is available here (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/), but only as tarballs. There are no precompiled versions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 28, 2020, 04:10:46 pm
The latest k-firmware: https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)
The latest m-firmware: https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/) and https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware (https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware)

The revisions are created by the SVN repo and just indicate changes in the repo. That could be a change for the 1.13k firmware, documentation or something else. For the current k-firmware under development (1.13k) the directory revision of the trunk directory tells you about any new changes. The m-firmware is released as finished version without any revisions, but the SVN will add a revision automatically for each new version. Simply ignore any revisions for the m-firmware (latest is 1.39m).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on April 28, 2020, 05:14:53 pm
Thanks, you both use the same repo and with the same login right? (user name kubi48 is what is shown but that is also Karl-Heinz Kübbeler username on the Mikrocontroller.net forum topic on the transistor tester (https://www.mikrocontroller.net/topic/248078)).
But ok so the SVN revision numbers all belong to the k-firmware on the SVN repository and just one is "taken" when you upload a tarball to the Markus subdirectory.
So basically since revision 798 there has been these additions to the k-firmware:
Code: [Select]
Rev Last log entry
804 support for Chinese board hiland_m644
805 einige Doku Korrekturen
807 removing bad commas
808 Beseitigung m644 Fehler ...
809 ESR Messung bei m644 fuer kleine Caps
813 hex und eep nach Project umbenannt von Gottfried
814 hex und eep nach Project umbenannt von Gottfried
815 Korrektur Zeitschleife mega2560
And meanwhile the "taken" revision numbers that are missing above are because of these:
Code: [Select]
File Rev. Age Author   Last log entry
 ComponentTester-1.34m.tgz 799 18 months kubi48   New Version 1.34m from Markus
 tt-res-e05.zip 800 18 months kubi48   Fernsteuerung der m-Version, Widerstaende
 tt-cap-e05.zip 801 18 months kubi48   Fernsteuerung der m-Version, Kondensatoren
 tt-bjt-e05.zip 802 17 months kubi48   Fernsteuerung der m-Version, Transistoren
 tt-jfet-e05.zip 803 17 months kubi48   Fernsteuerung der m-Version, JFETs
 ComponentTester-1.35m.tgz 806 14 months kubi48   Version 1.35m vom Markus R.
 ComponentTester-1.36m.tgz 810 11 months kubi48   neue Version 1.36m von Markus
 ComponentTester-1.37m.tgz 811 7 months kubi48   Fehlerbehebung,reverse-HFe...
 ComponentTester-1.38m.tgz 812 4 months kubi48   Version 1.38m von Markus R.
 ComponentTester-1.39m.tgz 816 4 weeks kubi48   neue Version 1.39m von Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 28, 2020, 05:45:01 pm
Not quite, Karl-Heinz manages the SVN repo, and I do the GitHub repo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 11, 2020, 11:03:29 am
I've started adding support for ATmega 640, 1280 and 2560 to the m-firmware. And since there are inexpensive and nice 3.5" LCD modules sold for Arduino I'm writing a driver for ILI9486. You can get them also with touchscreen, but only a few include an SPI touchscreen controller (ADS7843/XPT2046). Most modules simply wire the 4 lines of the resistive touchscreen to the connector. Other controllers used for those 320x480 LCDs are ILI9481, ILI9488, HX8357 and R61581, while the most common seems to be ILI9486. Unfortunately sellers rarely tell you which controller the LCD module comes with. Typical interfaces are SPI, 8 bit parallel and 16 bit parallel. If you like to sponsor some 3.5" LCD modules for development and testing please drop me a PM. I might feel inclined to write drivers for the alternative controllers too. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on May 12, 2020, 12:49:37 am
I have just purchased a BSIDE meter which I understand is based upon the same components as this open-source project.

Is anyone able to walk me through the steps required to update this to the latest firmware version?
Title: Re: $20 LCR ESR Transistor checker project
Post by: z01z on May 12, 2020, 08:50:33 am
Not quite, Karl-Heinz manages the SVN repo, and I do the GitHub repo.
Could you advise where/how to report firmware bugs?
In ttester-snapshot-20190319, in the file show_Resis_Cap.c line 231 should have #ifdef, not #ifndef (#ifdef RMETER_WITH_L)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 12, 2020, 02:22:25 pm
I have just purchased a BSIDE meter which I understand is based upon the same components as this open-source project.

Is anyone able to walk me through the steps required to update this to the latest firmware version?

Linux or Windows? k or m-firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 12, 2020, 02:28:19 pm
Could you advise where/how to report firmware bugs?
In ttester-snapshot-20190319, in the file show_Resis_Cap.c line 231 should have #ifdef, not #ifndef (#ifdef RMETER_WITH_L)

The best way is send an email (for k-firmware please see Karl-Heinz' documentation for his email address). However, I'll forward your report to Karl-Heinz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 12, 2020, 05:18:19 pm
Hello everybody!
I offer all owners of the AY-AT clone as well as the GM328A black board clone a slightly modified version of the m-firmware 1.39m in English!
I made this modification for myself in order to better understand the placement of information on the display with a resolution of 160x128. I think that madires will not be very angry with me for this? :)
You can download and check this firmware for 3 different processor frequencies - 8,16 and 20Mhz using the link from my resource https://yadi.sk/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke/English
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on May 12, 2020, 05:53:36 pm
@indman - Ru site says download limit exceeded..  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 13, 2020, 06:56:33 am
Cliff Matthews
OK! I put the same firmware files in one shared archive on another resource https://drive.google.com/open?id=1jcKJI49TL-M2101fzPR95rZTU5i72uwm
 :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on May 13, 2020, 08:33:07 am
Thank you so much for replying. I can use both Windows and Linux(Ubuntu). I am not sure what the current firmware is running but I could use either k or the m fork.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 13, 2020, 01:13:07 pm
Could you advise where/how to report firmware bugs?
In ttester-snapshot-20190319, in the file show_Resis_Cap.c line 231 should have #ifdef, not #ifndef (#ifdef RMETER_WITH_L)

The best way is send an email (for k-firmware please see Karl-Heinz' documentation for his email address). However, I'll forward your report to Karl-Heinz.

Karl-Heinz has fixed a few related issues: https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 13, 2020, 01:23:54 pm
Thank you so much for replying. I can use both Windows and Linux(Ubuntu). I am not sure what the current firmware is running but I could use either k or the m fork.

Somewhere in this huge thread are a few guides for Windows. For linux you could check ttester-1.13k.Bohu.English.pdf and ctester-1.39m.English.pdf at https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation. Both PDFs include a chapter about building and programming a new firmware on linux. Besides that, a web search for "programming AVR" should give you tons of links.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 13, 2020, 01:36:53 pm
I made this modification for myself in order to better understand the placement of information on the display with a resolution of 160x128. I think that madires will not be very angry with me for this? :)

Just a bit. ;D No! I'm happy about any contribution to the project!
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on May 13, 2020, 09:48:42 pm
There is this guide by tom666
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg810893/#msg810893

And a follow up on which versions of what give the best size
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg825078/#msg825078

And a detailed one from MIT for Windows 10 (and possibly back Win7)
http://fab.cba.mit.edu/classes/863.16/doc/projects/ftsmin/windows_avr.html (http://fab.cba.mit.edu/classes/863.16/doc/projects/ftsmin/windows_avr.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rhb on May 15, 2020, 03:34:17 pm
Would someone with knowledge (madires?) start a summary thread which describes the various versions and FW options?  One post per device or FW version giving the current status which is updated as things change.  I just did a google search to try to find out about compiling and flashing my BSIDE ESR02 Pro.  To say I got lost is an understatement.

I'd like to make some changes to it for ESR testing in circuit if no one has done them already. I really like the BSIDE case, so I'd like to use it even if I have to leave out other functions.  I'm fine getting a 2nd one.

For the SMPS I'm working on it needs to do the following:

1) limit the test voltage to 0.5 V so it does not turn on a diode in parallel with the caps I need to test

2) measure the DC resistance after the capacitor is charged to determine the resistance in parallel

3) measure the time period of a 0.5 V DC charging current multiple times to determine the capacitance

4) apply a 200kHz sine wave and measure the resistance of the cap and correct for the parallel resistance

5) beep when it has a stable reading

6) report if the ESR is good, bad or fair.

5) is not needed, but would be nice and if I'm modifying the FW I might as well add that if there is a free pin.

Thanks,
Reg
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2020, 04:35:18 pm
Would someone with knowledge (madires?) start a summary thread which describes the various versions and FW options?  One post per device or FW version giving the current status which is updated as things change.  I just did a google search to try to find out about compiling and flashing my BSIDE ESR02 Pro.  To say I got lost is an understatement.

indman has compiled an overview about various clones. Maybe he could post the current version. IIRC, the BSIDE uses the reference circuit and a ST7565 display. The default settings might work. BTW, if someone runs the m-firmware on a BSIDE please send me your settings for sharing (Clones file).

I'd like to make some changes to it for ESR testing in circuit if no one has done them already. I really like the BSIDE case, so I'd like to use it even if I have to leave out other functions.  I'm fine getting a 2nd one.

Based on your requirements you would have to design a hardware extension. A simple firmware mod wouldn't be able to do that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 15, 2020, 04:58:37 pm
indman has compiled an overview about various clones. Maybe he could post the current version. IIRC, the BSIDE uses the reference circuit and a ST7565 display. The default settings might work. BTW, if someone runs the m-firmware on a BSIDE please send me your settings for sharing (Clones file).

I have already offered BSideESR02 owners the latest version of k-firmware on page 247 (Reply # 6156)
In the near future I am going to compile a working version of m-firmware 1.39m for this clone. ;)

Title: Re: $20 LCR ESR Transistor checker project
Post by: rhb on May 15, 2020, 05:29:12 pm
Thanks.  I've downloaded the source and documentation for both versions.  I'll follow up when I've had time to study what I've got.

I'd still like to urge a summary thread as 249 pages of posts is rather daunting to search through.

Have Fun!
Reg

BTW I recently bought an HP 4145B semiconductor analyzer and a Tek 577 curve tracer.  I also have a 4284A and 4285A LCR meter  So I'll be doing some very detailed comparisons of performance when I manage to get all that stuff setup in my new lab.

My primary interest is low cost test gear. I eventually want to design some, but for now evaluating examples of this design and the nanoVNA (I also have  8753B and 8510C VNAs) should keep me busy for a while.

The motivation for wanting to build a modified version is this video:

https://www.youtube.com/watch?v=zZUYSwjvOxk (https://www.youtube.com/watch?v=zZUYSwjvOxk)
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on May 24, 2020, 04:52:26 am
I'm really struggling to flash the new firmware with the BSIDE ESR02. I have created another thread in the beginners forum if anyone is kind enough to look for me. I have soldered a six-pin header onto the board and have double-checked the wiring against indman's schematic and the wiring diagram on the back of the USBAsp. I have tried using the avrdude command-prompt (Win10) with verbose settings and various GUIs e.g Khazama AVR programmer. I get the same error throughout.

avrdude: Version 5.10, compiled on Jan 19 2010 at 10:45:23
         Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/ (http://www.bdmicro.com/)
         Copyright (c) 2007-2009 Joerg Wunsch

         System wide configuration file is "C:\WinAVR-20100110\bin\avrdude.conf"

         Using Port                    : lpt1
         Using Programmer              : USBAsp
avrdude: seen device from vendor ->www.fischl.de (http://www.fischl.de)<-
avrdude: seen product ->USBasp<-
         AVR Part                      : ATMEGA328P
         Chip Erase delay              : 9000 us
         PAGEL                         : PD7
         BS2                           : PC2
         RESET disposition             : dedicated
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           eeprom        65     5     4    0 no       1024    4      0  3600  3600 0xff 0xff
                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

         Programmer Type : usbasp
         Description     : USBasp, http://www.fischl.de/usbasp/ (http://www.fischl.de/usbasp/)

avrdude: auto set sck period (because given equals null)
avrdude: warning: cannot set sck period. please check for usbasp firmware update.
avrdude: error: programm enable: target doesn't answer. 1
avrdude: initialization failed, rc=-1
         Double check connections and try again, or use -F to override
         this check.


avrdude done.  Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rhb on May 24, 2020, 12:48:20 pm
I'll be watching de_light's progress closely as I intend to follow.  I printed out both the k and m manuals, but got rather lost in the details.

Is there a summary of the differences between the 2 FW versions? 

Thanks,
Reg
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 24, 2020, 02:56:59 pm
If you like to follow de_light's adventure in programming his BSIDE: https://www.eevblog.com/forum/beginners/usbasp-programming-atmel-328p/msg3078976/#msg3078976 (https://www.eevblog.com/forum/beginners/usbasp-programming-atmel-328p/msg3078976/#msg3078976)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 24, 2020, 03:10:47 pm
Is there a summary of the differences between the 2 FW versions? 

It would be a tough job to keep that up-to-date. ;) The m-firmware's README has a short list in section "What's different?". And if you scroll over the document overview you'll find more hints.
Title: Re: $20 LCR ESR Transistor checker project
Post by: djnz on May 24, 2020, 06:10:08 pm
Hi guys I need some help.

I am trying to repair an LCR TC1 tester. This tester has a separate STC microcontroller used for sleep / standby related stuff. This STC chip controls the enable pin of a boost converter which in turn powers the tester via a 7805. I think I have a dead STC chip because the enable pin never goes high.

I am attaching a schematic for this tester which was prepared by forum user Azure. Thanks Azure!

To temporarily fix the problem, I tried tying the boost enable pin to high. This allows the tester to start but freezes on the startup screen, presumably because the main ATmega chip waits for more handshake signals from the STC chip.

Has anyone captured these signals? Could someone with a working TC1 and a scope / logic analyzer please capture them?

(Pin 7 and 8 from U4 which is the STC chip to pins 10 and 11 of the main ATmega chip which are PD1 and PD2)

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 24, 2020, 06:46:49 pm
That won't help you much since U4 doesn't support reading its firmware for copying it to another MCU. You can only write it. The better solution is to mod the TC1 to be compatible with the OSHW firmwares and use one of those. One way is to program U4 with an alternative firmware (https://github.com/atar-axis/tc1-u4) and the other one is to replace it with a two-transistor circuit which also wastes less power (TC1-Mod.kicad.tgz at https://github.com/madires/Transistortester-Warehouse/tree/master/Hardware).
Title: Re: $20 LCR ESR Transistor checker project
Post by: djnz on May 24, 2020, 07:51:15 pm
Thanks for your reply, madires. The LCR T1 belongs to a colleague so I am hesitant to change the firmware. I myself have an AY-AT made from a kit and am very happy with it.

I was thinking I could write my own firmware for the STC to emulate the out-of-box behavior. Or perhaps use it as an excuse to dabble with some Padauks...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 26, 2020, 09:02:16 pm
Some good news for the Arduino afficionados. ;D I'm currently working on adding support for ATmega 1280/2560 to the m-firmware and added a few configuration switches to deal with the Arduino boards. Just in case someone likes to design a TransistorTester shield. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rhb on May 26, 2020, 11:45:28 pm
Some good news for the Arduino afficionados. ;D I'm currently working on adding support for ATmega 1280/2560 to the m-firmware and added a few configuration switches to deal with the Arduino boards. Just in case someone likes to design a TransistorTester shield. ;)

I gave a guy a nanoVNA  for designing an AR488  Uno GPIB-USB shield which is just a bare PCB that takes care of routing the wires.  If someone wants to design an OSHW  tester shield for the Mega, I'll be happy to pay for the cost of prototypes.

Have Fun!
Reg
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 27, 2020, 09:37:41 am
And if that someone likes to add one of the frequency counter options (basic/extended) to the shield I recommend to add a jumper to select PD7 or PE5 as frequency input for the MCU. The k-firmware's frequency counter needs a timer input pin which also supports pin--change interrupts. For the ATmega 2560 that would be PE6 (T3/INT6). Unfortunately the Arduino Mega doesn't provide PE6 at any of its female headers, but there's a work-around. Directly at the MCU PE6 (pin 8 ) can be easily bridged with PE5 (pin 7) which is available via the headers. The m-firmware uses PD7 (T0) as frequency input which is Arduino's 38.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 27, 2020, 01:24:30 pm
indman has compiled an overview about various clones. Maybe he could post the current version. IIRC, the BSIDE uses the reference circuit and a ST7565 display. The default settings might work. BTW, if someone runs the m-firmware on a BSIDE please send me your settings for sharing (Clones file).

Hi!
I adapted m-firmware 1.39m for clone BSideESR02(DTU-1701).
Inside the firmware archive in English for 2 frequencies of quartz 8 and 16 MHz, as well as configuration files for the madires collection. I also added a new beautiful edited font 8x8vf_win1251 for the madires collection. ;)

Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydron on May 27, 2020, 05:42:58 pm
I just tried your m-firmware build on my BSideESR02 Pro, and while it seems to load and test correctly, it keeps going back into the testing mode immediately after displaying a result - you get to look at the result for maybe a second max then it starts testing again. Is this expected? Does not happen on your k firmware, but I have never tried the m firmware before.

Note that I'm not trying to complain - I appreciate the work!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 27, 2020, 06:01:25 pm
You can change the cycle timeout by changing CYCLE_DELAY in config.h. Or by holding the start/test button at power on for more than 300ms the tester will start in auto-hold mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 27, 2020, 06:24:09 pm
- you get to look at the result for maybe a second max then it starts testing. Is this expected?

Here, one of the participants asked how k-firmware differs from m-firmware. I think that madires specifically made such a quick update of the results on the display so that its program differed from the k-firmware. For those people who think fast ;D I'm joking of course.
But seriously, then on the Russian-language forum this question is asked regularly in every 2 posts about m-firmware. This somewhat confuses users who are accustomed to firmware from Karl-Heinz. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydron on May 27, 2020, 07:03:57 pm
I actually did look in the "What's different" section of the 1.39m README before asking! Unfortunately this thread is pretty long by now, so it's a bit harder to search here too for the answer.

Thanks for the explanation madires - the 300ms button hold solution is good enough that I don't feel like dusting off an AVR toolchain to rebuild the firmware.

Edit: decided not to be lazy, found the setting in config.h to default to auto-hold and re-built it, now working as I like it :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnatGoSplat on May 29, 2020, 10:42:19 pm
I've got an old Transistor Checker with 2x16 text display and Atmega8L that I flashed to v1.13k.  Am I correct that this is the newest version that works on this device?

Unfortunately, it powers off after displaying the result after just 1-second which is too quick for my taste.  I'd like to extend the power off time to 5-10 seconds.  However, I have no idea how to do so.  I've had no success just experimenting.  I'm using Windows 10 x64.  Here's what I've tried:

When I compile, I get:
Code: [Select]
------ Build started: Project: TransistorTester, Configuration: Debug AVR ------
Build started.
Project "TransistorTester.cproj" (default targets):
Target "PreBuildEvent" skipped, due to false condition; ('$(PreBuildEvent)'!='') was evaluated as (''!='').
Target "CoreBuild" in file "C:\Program Files (x86)\Atmel\Studio\7.0\Vs\Compiler.targets" from project "C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\TransistorTester.cproj" (target "Build" depends on it):
Using "RunCompilerTask" task from assembly "C:\Program Files (x86)\Atmel\Studio\7.0\Extensions\Application\AvrGCC.dll".
Task "RunCompilerTask"
Shell Utils Path C:\Program Files (x86)\Atmel\Studio\7.0\shellUtils
C:\Program Files (x86)\Atmel\Studio\7.0\shellUtils\make.exe all --jobs 8 --output-sync
In file included from .././Transistortester.h:2:0,
                 from .././Calibrate_UR.c:1:
c:\program files (x86)\atmel\studio\7.0\toolchain\avr8\avr8-gnu-toolchain\avr\include\util\delay.h(92,3): warning: #warning "F_CPU not defined for <util/delay.h>" [-Wcpp]
# warning "F_CPU not defined for <util/delay.h>"
   ^
In file included from .././config.h:1128:0,
                 from .././Transistortester.h:11,
                 from .././Calibrate_UR.c:1:
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\autoconf.h(375,4): warning: #warning "SLEEP_MODE not possible with mega8" [-Wcpp]
   #warning "SLEEP_MODE not possible with mega8"
    ^
.././Calibrate_UR.c: In function 'Calibrate_UR':
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\Calibrate_UR.c(101,23): error: 'ANZ_MESS' undeclared (first use in this function)
   ADCconfig.Samples = ANZ_MESS; // set to configured number of ADC samples
                       ^
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\Calibrate_UR.c(101,23): info: each undeclared identifier is reported only once for each function it appears in
make: *** [Calibrate_UR.o] Error 1
Building file: .././Calibrate_UR.c
Invoking: AVR/GNU C Compiler : 5.4.0
"C:\Program Files (x86)\Atmel\Studio\7.0\toolchain\avr8\avr8-gnu-toolchain\bin\avr-gcc.exe"  -x c -funsigned-char -funsigned-bitfields -DDEBUG  -I"C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\include"  -O1 -ffunction-sections -fdata-sections -fpack-struct -fshort-enums -g2 -Wall -mmcu=atmega8 -B "C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\gcc\dev\atmega8" -c -std=gnu99 -MD -MP -MF "Calibrate_UR.d" -MT"Calibrate_UR.d" -MT"Calibrate_UR.o"   -o "Calibrate_UR.o" ".././Calibrate_UR.c"
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\mega8\Makefile(340,1): error: recipe for target 'Calibrate_UR.o' failed
make: *** Waiting for unfinished jobs....
Building file: .././Battery_check.c
Invoking: AVR/GNU C Compiler : 5.4.0
In file included from .././Transistortester.h:2:0,
                 from .././Battery_check.c:2:
c:\program files (x86)\atmel\studio\7.0\toolchain\avr8\avr8-gnu-toolchain\avr\include\util\delay.h(92,3): warning: #warning "F_CPU not defined for <util/delay.h>" [-Wcpp]
# warning "F_CPU not defined for <util/delay.h>"
   ^
In file included from .././config.h:1128:0,
                 from .././Transistortester.h:11,
                 from .././Battery_check.c:2:
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\autoconf.h(375,4): warning: #warning "SLEEP_MODE not possible with mega8" [-Wcpp]
   #warning "SLEEP_MODE not possible with mega8"
    ^
"C:\Program Files (x86)\Atmel\Studio\7.0\toolchain\avr8\avr8-gnu-toolchain\bin\avr-gcc.exe"  -x c -funsigned-char -funsigned-bitfields -DDEBUG  -I"C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\include"  -O1 -ffunction-sections -fdata-sections -fpack-struct -fshort-enums -g2 -Wall -mmcu=atmega8 -B "C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\gcc\dev\atmega8" -c -std=gnu99 -MD -MP -MF "Battery_check.d" -MT"Battery_check.d" -MT"Battery_check.o"   -o "Battery_check.o" ".././Battery_check.c"
Finished building: .././Battery_check.c
Building file: .././AutoCheck.c
Invoking: AVR/GNU C Compiler : 5.4.0
"C:\Program Files (x86)\Atmel\Studio\7.0\toolchain\avr8\avr8-gnu-toolchain\bin\avr-gcc.exe"  -x c -funsigned-char -funsigned-bitfields -DDEBUG  -I"C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\include"  -O1 -ffunction-sections -fdata-sections -fpack-struct -fshort-enums -g2 -Wall -mmcu=atmega8 -B "C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\gcc\dev\atmega8" -c -std=gnu99 -MD -MP -MF "AutoCheck.d" -MT"AutoCheck.d" -MT"AutoCheck.o"   -o "AutoCheck.o" ".././AutoCheck.c"
Finished building: .././AutoCheck.c
Building file: .././CalibrationCap.c
Invoking: AVR/GNU C Compiler : 5.4.0
In file included from .././Transistortester.h:2:0,
                 from .././CalibrationCap.c:23:
c:\program files (x86)\atmel\studio\7.0\toolchain\avr8\avr8-gnu-toolchain\avr\include\util\delay.h(92,3): warning: #warning "F_CPU not defined for <util/delay.h>" [-Wcpp]
# warning "F_CPU not defined for <util/delay.h>"
   ^
In file included from .././config.h:1128:0,
                 from .././Transistortester.h:11,
                 from .././CalibrationCap.c:23:
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\autoconf.h(375,4): warning: #warning "SLEEP_MODE not possible with mega8" [-Wcpp]
   #warning "SLEEP_MODE not possible with mega8"
    ^
"C:\Program Files (x86)\Atmel\Studio\7.0\toolchain\avr8\avr8-gnu-toolchain\bin\avr-gcc.exe"  -x c -funsigned-char -funsigned-bitfields -DDEBUG  -I"C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\include"  -O1 -ffunction-sections -fdata-sections -fpack-struct -fshort-enums -g2 -Wall -mmcu=atmega8 -B "C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\gcc\dev\atmega8" -c -std=gnu99 -MD -MP -MF "CalibrationCap.d" -MT"CalibrationCap.d" -MT"CalibrationCap.o"   -o "CalibrationCap.o" ".././CalibrationCap.c"
Finished building: .././CalibrationCap.c
Building file: .././ChargePin10ms.c
Invoking: AVR/GNU C Compiler : 5.4.0
"C:\Program Files (x86)\Atmel\Studio\7.0\toolchain\avr8\avr8-gnu-toolchain\bin\avr-gcc.exe"  -x c -funsigned-char -funsigned-bitfields -DDEBUG  -I"C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\include"  -O1 -ffunction-sections -fdata-sections -fpack-struct -fshort-enums -g2 -Wall -mmcu=atmega8 -B "C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\gcc\dev\atmega8" -c -std=gnu99 -MD -MP -MF "ChargePin10ms.d" -MT"ChargePin10ms.d" -MT"ChargePin10ms.o"   -o "ChargePin10ms.o" ".././ChargePin10ms.c"
Finished building: .././ChargePin10ms.c
In file included from .././Transistortester.h:2:0,
                 from .././ChargePin10ms.c:4:
c:\program files (x86)\atmel\studio\7.0\toolchain\avr8\avr8-gnu-toolchain\avr\include\util\delay.h(92,3): warning: #warning "F_CPU not defined for <util/delay.h>" [-Wcpp]
# warning "F_CPU not defined for <util/delay.h>"
   ^
In file included from .././config.h:1128:0,
                 from .././Transistortester.h:11,
                 from .././ChargePin10ms.c:4:
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\autoconf.h(375,4): warning: #warning "SLEEP_MODE not possible with mega8" [-Wcpp]
   #warning "SLEEP_MODE not possible with mega8"
    ^
Building file: .././CheckRotaryEncoder.c
Invoking: AVR/GNU C Compiler : 5.4.0
In file included from .././Transistortester.h:2:0,
                 from .././CheckRotaryEncoder.c:5:
c:\program files (x86)\atmel\studio\7.0\toolchain\avr8\avr8-gnu-toolchain\avr\include\util\delay.h(92,3): warning: #warning "F_CPU not defined for <util/delay.h>" [-Wcpp]
# warning "F_CPU not defined for <util/delay.h>"
   ^
In file included from .././config.h:1128:0,
                 from .././Transistortester.h:11,
                 from .././CheckRotaryEncoder.c:5:
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\autoconf.h(375,4): warning: #warning "SLEEP_MODE not possible with mega8" [-Wcpp]
   #warning "SLEEP_MODE not possible with mega8"
    ^
"C:\Program Files (x86)\Atmel\Studio\7.0\toolchain\avr8\avr8-gnu-toolchain\bin\avr-gcc.exe"  -x c -funsigned-char -funsigned-bitfields -DDEBUG  -I"C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\include"  -O1 -ffunction-sections -fdata-sections -fpack-struct -fshort-enums -g2 -Wall -mmcu=atmega8 -B "C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\gcc\dev\atmega8" -c -std=gnu99 -MD -MP -MF "CheckRotaryEncoder.d" -MT"CheckRotaryEncoder.d" -MT"CheckRotaryEncoder.o"   -o "CheckRotaryEncoder.o" ".././CheckRotaryEncoder.c"
Finished building: .././CheckRotaryEncoder.c
Building file: .././CheckUJT.c
Invoking: AVR/GNU C Compiler : 5.4.0
In file included from .././Transistortester.h:2:0,
                 from .././CheckUJT.c:1:
c:\program files (x86)\atmel\studio\7.0\toolchain\avr8\avr8-gnu-toolchain\avr\include\util\delay.h(92,3): warning: #warning "F_CPU not defined for <util/delay.h>" [-Wcpp]
# warning "F_CPU not defined for <util/delay.h>"
   ^
In file included from .././config.h:1128:0,
"C:\Program Files (x86)\Atmel\Studio\7.0\toolchain\avr8\avr8-gnu-toolchain\bin\avr-gcc.exe"  -x c -funsigned-char -funsigned-bitfields -DDEBUG  -I"C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\include"  -O1 -ffunction-sections -fdata-sections -fpack-struct -fshort-enums -g2 -Wall -mmcu=atmega8 -B "C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\gcc\dev\atmega8" -c -std=gnu99 -MD -MP -MF "CheckUJT.d" -MT"CheckUJT.d" -MT"CheckUJT.o"   -o "CheckUJT.o" ".././CheckUJT.c"
Finished building: .././CheckUJT.c
                 from .././Transistortester.h:11,
                 from .././CheckUJT.c:1:
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\autoconf.h(375,4): warning: #warning "SLEEP_MODE not possible with mega8" [-Wcpp]
   #warning "SLEEP_MODE not possible with mega8"
    ^
Building file: .././CheckPins.c
Invoking: AVR/GNU C Compiler : 5.4.0
In file included from .././Transistortester.h:2:0,
                 from .././CheckPins.c:3:
c:\program files (x86)\atmel\studio\7.0\toolchain\avr8\avr8-gnu-toolchain\avr\include\util\delay.h(92,3): warning: #warning "F_CPU not defined for <util/delay.h>" [-Wcpp]
# warning "F_CPU not defined for <util/delay.h>"
   ^
In file included from .././config.h:1128:0,
                 from .././Transistortester.h:11,
                 from .././CheckPins.c:3:
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\autoconf.h(375,4): warning: #warning "SLEEP_MODE not possible with mega8" [-Wcpp]
   #warning "SLEEP_MODE not possible with mega8"
    ^
.././CheckPins.c: In function 'CheckPins':
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\CheckPins.c(88,3): warning: #warning "hFE measurement without common emitter circuit" [-Wcpp]
  #warning "hFE measurement without common emitter circuit"
   ^
"C:\Program Files (x86)\Atmel\Studio\7.0\toolchain\avr8\avr8-gnu-toolchain\bin\avr-gcc.exe"  -x c -funsigned-char -funsigned-bitfields -DDEBUG  -I"C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\include"  -O1 -ffunction-sections -fdata-sections -fpack-struct -fshort-enums -g2 -Wall -mmcu=atmega8 -B "C:\Program Files (x86)\Atmel\Studio\7.0\Packs\atmel\ATmega_DFP\1.3.300\gcc\dev\atmega8" -c -std=gnu99 -MD -MP -MF "CheckPins.d" -MT"CheckPins.d" -MT"CheckPins.o"   -o "CheckPins.o" ".././CheckPins.c"
Finished building: .././CheckPins.c
Done executing task "RunCompilerTask" -- FAILED.
Done building target "CoreBuild" in project "TransistorTester.cproj" -- FAILED.
Done building project "TransistorTester.cproj" -- FAILED.

Build FAILED.
========== Build: 0 succeeded or up-to-date, 1 failed, 0 skipped ==========


If I change it to use External Makefile and select the Makefile from the mega8 folder, I get:
Code: [Select]
------ Build started: Project: TransistorTester, Configuration: Debug AVR ------
Build started.
Project "TransistorTester.cproj" (default targets):
Target "PreBuildEvent" skipped, due to false condition; ('$(PreBuildEvent)'!='') was evaluated as (''!='').
Target "CoreBuild" in file "C:\Program Files (x86)\Atmel\Studio\7.0\Vs\Compiler.targets" from project "C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\TransistorTester.cproj" (target "Build" depends on it):
Using "RunCompilerTask" task from assembly "C:\Program Files (x86)\Atmel\Studio\7.0\Extensions\Application\AvrGCC.dll".
Task "RunCompilerTask"
Shell Utils Path C:\Program Files (x86)\Atmel\Studio\7.0\shellUtils
C:\Program Files (x86)\Atmel\Studio\7.0\shellUtils\make.exe -C "C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\mega8" -f "Makefile" all
make: Entering directory 'C:/Users/Shawn/Documents/Atmel Studio/7.0/TransistorTester/TransistorTester/mega8'
The syntax of the command is incorrect.
The syntax of the command is incorrect.
The system cannot find the path specified.
avr-gcc  -Wall -DLCD_ST7565_H_FLIP=1 -DLCD_ST7565_H_OFFSET=4 -DLCD_ST7565_V_FLIP=0 -DFONT_7X12 -DICON_TYPE=3 -DBIG_TP -DREF_C_KORR=4 -DREF_L_KORR=40 -DC_H_KORR=5 -DRMETER_WITH_L -DCAP_EMPTY_LEVEL=4 -DESR_ZERO=29 -DNO_AREF_CAP -DUSE_EEPROM -DPULLUP_DISABLE -DANZ_MESS=44 -DPOWER_OFF -DBAT_OUT=150 -DBAT_POOR=6400 -mcall-prologues -DINHIBIT_SLEEP_MODE -I. -DF_CPU=8000000UL -DF_CPU_HZ=8000000 -DMHZ_CPU=8 -mmcu=atmega8 -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT lcd_hw_4_bit.o -MF ../Obj/mega8/dep/lcd_hw_4_bit.o.d  -ffunction-sections -fdata-sections -c -o ../Obj/mega8/lcd_hw_4_bit.o ../lcd_hw_4_bit.S
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\lcd_hw_4_bit.S(8,0): error: opening dependency file ../Obj/mega8/dep/lcd_hw_4_bit.o.d: No such file or directory

^
compilation terminated.
make: *** [../Obj/mega8/lcd_hw_4_bit.o] Error 1
C:\Users\Shawn\Documents\Atmel Studio\7.0\TransistorTester\TransistorTester\finish.mk(3,1): error: recipe for target '../Obj/mega8/lcd_hw_4_bit.o' failed
make: Leaving directory 'C:/Users/Shawn/Documents/Atmel Studio/7.0/TransistorTester/TransistorTester/mega8'
Done executing task "RunCompilerTask" -- FAILED.
Done building target "CoreBuild" in project "TransistorTester.cproj" -- FAILED.
Done building project "TransistorTester.cproj" -- FAILED.

Build FAILED.
========== Build: 0 succeeded or up-to-date, 1 failed, 0 skipped ==========

I've spent 2 afternoons messing with this, and it doesn't look like I"m going to figure it out.  What am I missing?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2020, 07:33:43 am
"The syntax of the command is incorrect." can be caused by a bad PATH variable, i.e. some programs aren't found.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on May 30, 2020, 08:41:56 am
Having spent so much time reading in order to understand how to upgrade and flash my AY-AT transistor tester I decided to document as much as possible of what I've learned: https://github.com/blurpy/transistor-tester

Maybe someone else will find it useful :)

Thanks a lot, blurrpy. This is extremely useful. It is true that the thread has become very large and searching for information is difficult. One really needs some wiki that gathers all up to date information and proper links.  Your repository is a very good step towards this.


I  have fixed and upgraded my AY-AT board, but still have a problem :

The voltage at pin 28 is not right.  while I have 8.7 V  battery, the pin at 28 is only 7.1 V  1.7V (corrected). So the proc thinks that the battery is dead and shutdown.

The problem seems to come from transistor  T3 ( SS9012).  What is a good replacement for it ?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 30, 2020, 08:59:43 am
The voltage at pin 28 is not right.  while I have 8.7 V  battery, the pin at 28 is only 7.1 V. So the proc thinks that the battery is dead and shutdown.
What current does your device draw on 9V battery?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2020, 09:50:17 am
7.1V at pin 28? The ATmega doesn't like any voltage higher than 5V and the AY-AT has a 4:1 voltage divider at pin 28 for measuring the battery voltage. Or do you mean that the tester displays a battery voltage of 7.1V? In that case the voltage at pin 28 should be around 1.77V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on May 30, 2020, 10:18:04 am
7.1V at pin 28? The ATmega doesn't like any voltage higher than 5V and the AY-AT has a 4:1 voltage divider at pin 28 for measuring the battery voltage. Or do you mean that the tester displays a battery voltage of 7.1V? In that case the voltage at pin 28 should be around 1.77V.

Yes, sorry for the mistake.

I have made many tests. Changed  T3  and T2 ( which looked OK anyway). I  realized I had a set of chinese transistors with these values in my drawers. So changed them for the same.

I am making the tests with the IC off .

I have 7.1 V  at pin 2 of IC2  while I have  8.4 V at the battery.
The led is OK.  it does not light when the IC is  OFF but lights when I put it ON.  There is no change whether I put or not the IC.

I have measure the nearby resistors :
R7,R10, R15,.
I have changed the 10 uF  capacitor. Suppress the two 100 nF  to test them.
All OK.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 30, 2020, 10:35:16 am
AlcidePiR2
I ask you one more time - what current does the circuit consume from a 9V battery?
Check the condition of the 7550 stabilizer as well as the diode assembly SRV05-4 and the 6V8A suppressor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on May 30, 2020, 10:45:18 am
The voltage at pin 28 is not right.  while I have 8.7 V  battery, the pin at 28 is only 7.1 V. So the proc thinks that the battery is dead and shutdown.
What current does your device draw on 9V battery?

This is a good point !

Before even measuring this, I  checked  the battery voltage when I pressed the button, and it drops to 7.2V .  So the problem was not at all where I searched for.
This is because I first checked the battery voltage, and then only  VBAT when I  pressed the button.

At least a mystery  is solved.  I changed the transistors  for no reason. There should be  a short ( or nearly) somewhere.

Then I checked the current : 160 mA. (  the IC  is  removed).

Any hint for a good candidate for this short ?

Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on May 30, 2020, 10:48:45 am
AlcidePiR2
I ask you one more time - what current does the circuit consume from a 9V battery?
Check the condition of the 7550 stabilizer as well as the diode assembly SRV05-4 and the 6V8A suppressor.


I was in my workshop checking for the amp ( see my previous post).   The 7550 is good. I  had changed it to MCP1702 and it is delivering good 5.0V.

I  will check  now the diode assembly SRV05-4 and the 6V8A suppressor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2020, 10:53:14 am
My bet is on the SRV05-4.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on May 30, 2020, 12:02:42 pm
My bet is on the SRV05-4.

Ca I just remove it  to test. As well as the P6KE6V8a ? Before I  eventually get some for replacement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2020, 01:00:16 pm
Yes, the tester will work without them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on May 30, 2020, 01:24:13 pm
My bet is on the SRV05-4.

You WIN !

there was  33 Ohms  between pins 2 and 5 of the SRV05-4.  SO there was really a surge that destroyed both the SRV05-4 and the IC.

Now everything is working  fine.  Thanks to you,   Indman and blurpy  for the help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2020, 03:00:16 pm
You're welcome! The No. 1 cause is a charged capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnatGoSplat on May 30, 2020, 08:48:34 pm
"The syntax of the command is incorrect." can be caused by a bad PATH variable, i.e. some programs aren't found.

Yeah, unfortunately I can't figure out what it needs.  The error doesn't say what it's looking for.  Should I even be using the external Makefile with Atmel Studio?

I actually fixed the fast shutoff time by adding a 27k pull-up resistor to pin 13 PD7.  I guess that was needed after a certain version of firmware.  However, I still need to fix µ and Ω not showing up with the correct character on the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 31, 2020, 06:40:27 am
  However, I still need to fix µ and Ω not showing up with the correct character on the display.
Use the flag CFLAGS + = -DLCD_CYRILLIC in the makefile
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on May 31, 2020, 07:45:26 am
Hello All,

After repairing my AY-AT tester and properly flashing the compiled code to  the Atmega328P, I want now to change some settings, so I have to compile the code myself.
I used the 1.39m version,
set up everything according to the clones document,  installed avr-gcc but I have one  compilation error. Did I do something wrong ?

Quote

avr-gcc -mmcu=atmega328 -Wall -mcall-prologues -I. -Ibitmaps -DF_CPU=16000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT display.o -MF dep/display.o.d -c display.c
display.c: In function 'Display_HexByte':
display.c:403:3: warning: implicit declaration of function 'Display_HexDigit'; did you mean 'Display_HexByte'? [-Wimplicit-function-declaration]
  403 |   Display_HexDigit(Digit);
      |   ^~~~~~~~~~~~~~~~
      |   Display_HexByte

avr-gcc -mmcu=atmega328 -Wl,-Map=ComponentTester.map main.o user.o pause.o adjust.o ADC.o probes.o display.o resistor.o cap.o semi.o inductor.o tools_misc.o tools_signal.o SPI.o I2C.o serial.o commands.o OneWire.o IR_RX.o IR_TX.o DHTxx.o HD44780.o ST7565R.o ILI9341.o PCD8544.o ST7735.o ST7920.o SSD1306.o ILI9163.o STE2007.o PCF8814.o ST7036.o VT100.o ADS7843.o wait.o   -o ComponentTester
/usr/local/opt/avr-binutils/bin/avr-ld: display.o: in function `Display_HexByte':
/Volumes/DATA/FIRMWARE/ComponentTester-1.39m/display.c:403: undefined reference to `Display_HexDigit'
/usr/local/opt/avr-binutils/bin/avr-ld: /Volumes/DATA/FIRMWARE/ComponentTester-1.39m/display.c:407: undefined reference to `Display_HexDigit'
collect2: error: ld returned 1 exit status
make: *** [ComponentTester] Error 1



I  set up the ST7735  SPI interface as

/*
 *  ST7735, SPI interface (bit-bang, 4 wire)
 */

#if 1
#define LCD_ST7735                      /* display controller ST7735 */
#define LCD_GRAPHIC                     /* graphic display */
#define LCD_COLOR                       /* color display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RES          PD4            /* port pin used for /RESX (optional) */
#define LCD_CS           PD5            /* port pin used for /CSX (optional) */
#define LCD_DC           PD3            /* port pin used for D/CX */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SDA          PD1            /* port pin used for SDA */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       160            /* number of vertical dots */
//#define LCD_FLIP_X                      /* enable horizontal flip */
#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_ROTATE                      /* switch X and Y (rotate by 90∞) */
//#define LCD_OFFSET_X     4               /* enable x offset of 2 or 4 dots */
//#define LCD_OFFSET_Y     2               /* enable y offset of 1 or 2 dots */
#define LCD_LATE_ON                     /* turn on LCD after clearing it */
/* font and symbols: horizontally aligned & flipped */
#define FONT_10X16_HF                   /* 10x16 font */
//#define FONT_10X16_ISO8859_2_HF         /* 10x16 Central European font */
//#define FONT_8X16_WIN1251_HF            /* 8x16 cyrillic font */
#define SYMBOLS_30X32_HF                /* 30x32 symbols */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SDA        /* port pin used for MOSI */
#endif
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on May 31, 2020, 08:18:28 am
I looked to the display.c code  and found the problem.

I had disabled  the IR flags where  Display_HexDigit is defined

and enabled

#define SW_FONT_TEST

which uses Display_HexDigit

Maybe some comment would be welcome saying this (maybe its there and I did not see it)

I removed

// #define SW_FONT_TEST

and now it compiles OK
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 31, 2020, 11:30:18 am
Thanks! You've found a bug in the "#ifdef" management for the functions Display_HexDigit() and Display_HexByte(). I'll fix it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: belzrebuth on May 31, 2020, 11:45:50 am
Thread is quite long to search I'm afraid and by seeing it I realised I haven't updated my tester for a while now..(2-3 years!)
What would be the latest version for a EZM328 tester?
Thanks:)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 31, 2020, 12:18:24 pm
k-firmware: 1.13k (maybe mega328_GM328)
m-firmware: 1.39m
If your tester is a GM328A it might need the PD5 mod (see https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/5550/ (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/5550/)).
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on May 31, 2020, 01:09:34 pm
Having spent so much time reading in order to understand how to upgrade and flash my AY-AT transistor tester I decided to document as much as possible of what I've learned: https://github.com/blurpy/transistor-tester

Maybe someone else will find it useful :)

I already said that this was helpful, but I must say it again, when I realized that in your repository are the examples of Makefile, config.h and config328.h for the AY-AT boards.

Indeed, after repairing my board, and successfully flashing  the  compiled files provided by Indman, I wanted to change some options. I had then to compile the code by myself.  Starting from  Madires repository. But although the files are well written an documented,   the multiplicity of options makes it difficult, and my first trys were not successful. Then I realized that you posted as well the config files.
Using them was immediate success. So you saved my day. Thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on May 31, 2020, 04:48:53 pm
I'm sure that this information is somewhere in the thread, but I could not find it.

What version of the AVR toolchain generates the most compact code? Ideally the Windows version, but if there is a Linux version that generates even more compact code, I would have no problems using it

I know that different compiler versions generate code with different optimizations, and that results in binaries with different lengths
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 31, 2020, 06:33:26 pm
robca
For Windows optimal
https://drive.google.com/file/d/1ioYbEuzrPkiSpJ51IamuwcZ1IU4PplbI/view?usp=sharing
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnatGoSplat on May 31, 2020, 07:02:15 pm
  However, I still need to fix µ and Ω not showing up with the correct character on the display.
Use the flag CFLAGS + = -DLCD_CYRILLIC in the makefile

I would like to, but unfortunately I can't compile anything.  Spent another evening trying to figure out how to compile and no go.
Would someone who is able to compile 1.13k for mega8 be willing to help me out with this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 31, 2020, 07:25:37 pm
GnatGoSplat look zip file  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: GnatGoSplat on May 31, 2020, 08:17:17 pm
GnatGoSplat look zip file  ;)

Thanks so much, that did fix the issue with the characters.
Looks like I broke it somehow though.  Now it's very, very slow, doesn't respond much of the time when I press the button, and returns incorrect results for capacitors.  Definitely not your build because I flashed the original one back in and it's still super slow.  I have no idea what I messed up.  Nothing looks broken.  Weird.

Might be the fuses aren't right.  I'll have to look into that.

UPDATE: It was the fuses.  All is well now.
Title: Re: $20 LCR ESR Transistor checker project
Post by: blurpy on June 01, 2020, 07:22:24 am
Having spent so much time reading in order to understand how to upgrade and flash my AY-AT transistor tester I decided to document as much as possible of what I've learned: https://github.com/blurpy/transistor-tester

Maybe someone else will find it useful :)

I already said that this was helpful, but I must say it again, when I realized that in your repository are the examples of Makefile, config.h and config328.h for the AY-AT boards.

Indeed, after repairing my board, and successfully flashing  the  compiled files provided by Indman, I wanted to change some options. I had then to compile the code by myself.  Starting from  Madires repository. But although the files are well written an documented,   the multiplicity of options makes it difficult, and my first trys were not successful. Then I realized that you posted as well the config files.
Using them was immediate success. So you saved my day. Thanks again.

Nice to hear you found my documentation useful and got your tester working, that makes it worth the effort!
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on June 01, 2020, 06:17:19 pm
I'm programming my AY-AT tester and before overwriting the original 328p I tried reading the firmware (which I assumed was pointless and expected to fail due to the protection bits). But my chip was not protected, and I have a copy of the firmware and EEPROM.

I'm not sure if mine was an exception, or all AY-AT ship without protection fuses set. I thought I'd mention it in case anyone here wants a copy (just reply here and I'll copy it somewhere)

EDIT: attached as ZIP. firmware, eeprom and fuses configuration
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 01, 2020, 06:30:14 pm
You could also zip and attach them to your post. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: blurpy on June 01, 2020, 07:26:46 pm
I'm programming my AY-AT tester and before overwriting the original 328p I tried reading the firmware (which I assumed was pointless and expected to fail due to the protection bits). But my chip was not protected, and I have a copy of the firmware and EEPROM.

I'm not sure if mine was an exception, or all AY-AT ship without protection fuses set. I thought I'd mention it in case anyone here wants a copy (just reply here and I'll copy it somewhere)

Nice! My AY-AT had the protection bits set so I was unable to make a copy.

+1 to madires' suggestion.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on June 01, 2020, 08:20:29 pm
More than anything, I wanted to be sure it was not something everyone had... just attached to the previous message as ZIP
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 01, 2020, 08:39:53 pm
More than anything, I wanted to be sure it was not something everyone had... just attached to the previous message as ZIP
Thanks!
This version for AY-AT is based on the rather outdated 1.12k from Karl-Heinz. Its only advantage is the ability to test the sensors DHT11-DS18B20 and IR Encoder-Decoder, which the Chinese added.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on June 01, 2020, 08:43:41 pm
I'm compiling 1.39m with SW_ONEWIRE_SCAN but no IR functionality, and I'm getting a compilation error: C:\Work\AvrAYAT\ComponentTester-1.39m/display.c:407: undefined reference to `Display_HexDigit'

I think that the problem is in the following snippet in display.c

Code: [Select]
/* ************************************************************************
 *   display of values and units
 * ************************************************************************ */


#if defined (SW_IR_RECEIVER) || defined (HW_IR_RECEIVER) || defined (SW_IR_TRANSMITTER)

/*
 *  display single hexadecimal digit
 *
 *  requires:
 *  - value to display (0-15)
 */

void Display_HexDigit(uint8_t Digit)
{
  /*
   *  convert value into hex digit:
   *  - 0-9: ascii 48-57
   *  - A-F: ascii 65-70
   */

  if (Digit < 10) Digit += 48;     /* 0-9 */
  else Digit += (65 - 10);         /* A-F */
  Display_Char(Digit); 
}

#endif



#if defined (SW_IR_RECEIVER) || defined (HW_IR_RECEIVER) || defined (SW_ONEWIRE_SCAN) || defined (SW_FONT_TEST)

/*
 *  display byte as hexadecimal number
 *
 *  requires:
 *  - value to display (0-255)
 */

void Display_HexByte(uint8_t Value)
{
  uint8_t           Digit;

  /* first digit */
  Digit = Value / 16;
  Display_HexDigit(Digit);

  /* second digit */
  Digit = Value % 16;
  Display_HexDigit(Digit);
}

#endif

in particular

Code: [Select]
/* ************************************************************************
 *   display of values and units
 * ************************************************************************ */

#if defined (SW_IR_RECEIVER) || defined (HW_IR_RECEIVER) || defined (SW_IR_TRANSMITTER)

should be

Code: [Select]
#if defined (SW_IR_RECEIVER) || defined (HW_IR_RECEIVER) || defined (SW_ONEWIRE_SCAN) || defined (SW_IR_TRANSMITTER)

When I make that change, it compiles without problems, but I don't understand enough of the code to know if there are any negative side effects elsewhere
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 01, 2020, 08:54:15 pm
AlcidePiR2 was one page faster. :) It's a fault in the #ifdef management for two functions and will be fixed in the next version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on June 01, 2020, 09:01:17 pm
AlcidePiR2 was one page faster. :) It's a fault in the #ifdef management for two functions and will be fixed in the next version.
Sorry I missed it, too many posts to read  :-[

Can I assume my fix is safe?
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on June 01, 2020, 10:16:51 pm
One more question, if I may

My AY-AT seems to have a pretty bad encoder and I have problems getting double clicks to be recognized. I will replace it, but right now I don't have one handy. I'd like to lengthen the time for a double click, so that it's not such a hit or miss affair.

I looked at user.c, the TestKey function. In the following snippet:

Code: [Select]
      /* determine key press type */
      if (Ticks > 26)                   /* long (>= 300ms) */
      {
        Key = KEY_LONG;                 /* signal long key press */
      }
      else                              /* short (< 300ms) */
      {
        Key = KEY_SHORT;                /* signal short key press */

        /* check for second key press if requested */
        if (Mode & CHECK_KEY_TWICE)
        {
          MilliSleep(50);               /* delay for checking key again */
          Ticks = 20;                   /* timeout of 200ms */
 
          while (Ticks > 0)             /* timeout loop */
          {
            Test = BUTTON_PIN & (1 << TEST_BUTTON);    /* get button status */         

            if (Test == 0)                             /* test button pressed */
            {
              MilliSleep(30);                          /* time to debounce */
              Test = BUTTON_PIN & (1 << TEST_BUTTON);  /* get button status */

              if (Test == 0)                           /* test button still pressed */
              {
                Ticks = 1;                             /* end loop */
                Key = KEY_TWICE;                       /* signal two key presses */
                MilliSleep(200);                       /* smooth UI */
              }
            }

            Ticks--;                                   /* decrease timeout */
            MilliSleep(10);                            /* wait 10ms */
          }
        }

I think that if I change
Code: [Select]
if (Ticks > 26)                   /* long (>= 300ms) */ to a value higher than 26, say 35, I should get a longer timeout for a long press to be recognized, and
Code: [Select]
Ticks = 20;                   /* timeout of 200ms */
while (Ticks > 0)             /* timeout loop */
to 25, that should give me more time to have a double click recognized.

@madires can you please let me know if I'm on the right path? It's rather inconvenient for me to remove the Atmega328p to program it and reinstall, so I'd like to minimize the amount of modify/compile/flash, if you have time to chime in. If not, I'll try it out

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 02, 2020, 11:42:23 am
Can I assume my fix is safe?

Yep!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 02, 2020, 12:07:16 pm
I think that if I change
Code: [Select]
if (Ticks > 26)                   /* long (>= 300ms) */ to a value higher than 26, say 35, I should get a longer timeout for a long press to be recognized,

You also need to change:
Code: [Select]
          if (Ticks > 26) Run = 0;      /* end loop if 300ms are reached */

to the same value. With 35 the minimum time for a long button press will be (35 + 1) * 10ms + 30ms = 390ms. This is the time you have to press the button to be detected as a long button press. It doesn't have any impact on the double-press.

and
Code: [Select]
Ticks = 20;                   /* timeout of 200ms */
while (Ticks > 0)             /* timeout loop */
to 25, that should give me more time to have a double click recognized.

Yes, that will increase the timeout for the second button press (25 * 10ms = 250ms), i.e. the time in which the button has to be pressed again to be detected as a double-press.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ifishtoo on June 03, 2020, 02:15:17 am
I would very much like a copy of that firmware.  i am still trying to decide which one to buy first. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on June 03, 2020, 04:44:22 pm
I would very much like a copy of that firmware.  i am still trying to decide which one to buy first.
I attached the ZIP file to my original message just after madires and blurpy's suggestion. It's a few messages before this one
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on June 04, 2020, 09:16:53 pm
I started from a standard AY-AT clone.

inspired by blurpy documentation, I made several changes after replacing the SRV05-4 which was fried.

- changed the 7550 to a MCP1702
- changed the 680R resistors to 681R 0.1%
- changed the 470 kR  resistors to 475kR 0.1%
- replaced the TL431  by a MAX6126 ( see attached pict)
- replaced  the 8 Mhz crystal by a 20 Mhz
- flashed the 1.39m  firmware after compiling with appropriate changes in Makefile, config.h, config_328.h, in particular for
/* Rl in Ohms */
#define R_LOW            681

/* Rh in Ohms */
#define R_HIGH           475000


Everything is working, except that the perfs are quite deceptive.
I have measure several high precision resistors ( 0.01%  and 0.05%)
but it seems that the precision that can be  achieved is only 2% for measuring resistors.

Is this normal ?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 04, 2020, 09:22:16 pm
Have you run the self-adjustment incl. the film cap procedure?
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on June 04, 2020, 10:35:01 pm
Have you run the self-adjustment incl. the film cap procedure?

I have run the  items from the menu
- Test
- Adjustment

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 05, 2020, 06:02:37 am
AlcidePiR2 You did it?
"Before running the self-adjustment the first time, please measure a film
capacitor with a value between 100nF and 3.3µF three times at least to let the
tester self-adjust the offsets mentioned above."
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on June 05, 2020, 06:16:10 am
AlcidePiR2 You did it?
"Before running the self-adjustment the first time, please measure a film
capacitor with a value between 100nF and 3.3µF three times at least to let the
tester self-adjust the offsets mentioned above."

No, I did not see that. Will do it today.
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on June 05, 2020, 08:42:46 am
I have

measure 3 time a  film cap 1uF 1%  and adjust again, but this did not changed anything.  ( Mes A )

Then

- suppress the opto coupler option to give more room to the code ( 97% instead of 99.9 %)
- changed the  Low Fuse to 0xF7 instead of 0xFF  ( crystal)

reflash the chip,  measure 3 times the  film cap

Test
Adjustment

Then things improved and I get something that seems to be in par with what is expected from the 10 bit resolution of the AD converter of the Atmega328 ( 0.1%)  ( Mes B and B bis)


R   prec         Mes A      Mes B   Mes B bis
            
681   0.10%   680.2     680.1   679.3
475k   0.10%   474.4     474.4   474.2
100   0.01%   101.8     99.7     99.6
10k    0.01%   9801           9992    9993
1M     0.05%   998.6k     998.7   998.2


I dont know if anything better can be expected without adding an external ADC.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 05, 2020, 09:16:45 am
AlcidePiR2
I suggest you make the same measurements on k-firmware 1.13k and compare the results. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: AlcidePiR2 on June 05, 2020, 12:37:52 pm
AlcidePiR2
I suggest you make the same measurements on k-firmware 1.13k and compare the results. :)

This is done with the I.13k

with the following changes in the autoconf.h because the resistors I had in 0.1% accuracy were not the 680/470k standards.


/* check the R_L_VAL and R_H_VAL setting */
#ifndef R_L_VAL
  #define R_L_VAL 6810         // standard value 680 Ohm, multiplied by 10 for 0.1 Ohm resolution
#endif
#ifndef R_H_VAL
  #define R_H_VAL 47500      // standard value 470000 Ohm, multiplied by 10, divided by 100
#endif


The results are comparable. Maybe slightly better

679.6
474.5
99.3
10.01-2 k (variations in a sequence of measures)
999.4-8 k (variations in a sequence of measures)





Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on June 05, 2020, 01:07:53 pm
My saga with the esr02pro has taken a temporary pause as my friend needed his multimeter back and I am awaiting shipment of my new multimeter (with long delays from covid19).

The BSIDE people have kindly sent me out a free gift of the ESR02 (non pro) version, photo below. Does this look familiar to anyone in terms of a clone?

(https://i.postimg.cc/bsyqGgrj/812045228-1689402026.jpg) (https://postimg.cc/bsyqGgrj)

(https://i.postimg.cc/56sb8zQQ/952084891978131025.jpg) (https://postimg.cc/56sb8zQQ)


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 05, 2020, 01:47:56 pm
Looks like a MG328 with a slightly modified probe area (connectors moved around).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 05, 2020, 02:05:20 pm
The BSIDE people have kindly sent me out a free gift of the ESR02 (non pro) version, photo below. Does this look familiar to anyone in terms of a clone?

I think that this clone is almost no different from MG328(BigDisplay) on my resource  ;)
https://yadi.sk/d/yW8xa5NJgUo5z/MG328(BigDisplay) (https://yadi.sk/d/yW8xa5NJgUo5z/MG328(BigDisplay))
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 18, 2020, 07:50:15 pm
I updated the comparative table on clones and added information on 5V to the regulator and to referensny source 2.5V. I did not give exact marking of details as the Chinese vendors can use different marking and the name. :)
I updated the comparative table on clones and added information display size in inches,supply controller for LCR-T1/T7, update firmware version posible  ;)

P.S Edit - Fixed some display size errors in inches
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stan21 on June 25, 2020, 05:51:54 am
Hello
I purchase the device from Kuman via Amazon https://www.amazon.com/gp/product/B071Y5CHPK (https://www.amazon.com/gp/product/B071Y5CHPK)
I ran self-adjustment
I noticed that device gives wrong values for hFE; so for MPS222A transistor it shows hFE 425 while 2 other testers (Synometer VC9808 and another one, Mastech) show consistently  250 which is more reasonable.
Can anything be done to fix that or I am just being unlucky with bad device?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 25, 2020, 10:00:16 am
The hFE can differ based on test currents and voltages. Also be aware that the firmware of the transistortester measures hFE in a common emitter configuration and also in a common collector configuration. The higher value of both measurements is displayed. I can't say anything about the DMMs. But you can set up a simple circuit to measure the hFE yourself to verify the value.
Title: Re: $20 LCR ESR Transistor checker project
Post by: PedroDaGr8 on June 25, 2020, 08:59:28 pm
I updated the comparative table on clones and added information on 5V to the regulator and to referensny source 2.5V. I did not give exact marking of details as the Chinese vendors can use different marking and the name. :)
I updated the comparative table on clones and added information display size in inches,supply controller for LCR-T1/T7, update firmware version posible  ;)

For your comparison, it would be good to indicate what is different between the AY-AT and the GM328A. This would help people in identifying their version. If there are no definitive differences, then it might be worthwhile to combine the two entries.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 26, 2020, 06:26:08 am
GM328A(B) is a clone model that fully repeats the AY-AT model, but is assembled on SMD components(excluding processor in version A) and has a black board color. I do not know in which version GM328A is currently being produced, but according to the reviews of many owners of such models, they have an error in tracing the frequency meter circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stan21 on June 26, 2020, 09:17:39 am
The hFE can differ based on test currents and voltages. Also be aware that the firmware of the transistortester measures hFE in a common emitter configuration and also in a common collector configuration. The higher value of both measurements is displayed. I can't say anything about the DMMs. But you can set up a simple circuit to measure the hFE yourself to verify the value.
This only proves advantage of regular OEM LCR-meter. I have 2 and both show the same correct value of hFE.
One cannot expect any reliability from $7  toy made by amateurs enthusiasts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 26, 2020, 09:54:43 am
Have you verified by a manual hFE measurement that your DMMs show a reasonable value? Both DMMs might use the same measuring method, hence the matching values. BTW, a DMM is not an LCR meter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stan21 on June 26, 2020, 10:36:19 am
Have you verified by a manual hFE measurement that your DMMs show a reasonable value? Both DMMs might use the same measuring method, hence the matching values. BTW, a DMM is not an LCR meter.
I am not familiar with your slang and have no idea what 'DMM' is. I have an LCR-meter VC-9808, multimeter Mastech MAS345 and simple anlogue multimeter 5828. All 3 have hFE measurement, and all 3 show same hFE for MPS2222A in the range of 240-250, while this self-made gadget shows 425. I have no reason not to trust OEM meters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 26, 2020, 11:56:12 am
Stan21,
1. DMM is the common designation for Digital Multi Meter! It's a shame if you did not know these simple things before this time.
2. VC-9808, Mastech MAS345 - this is DMM! They are not specialized LCR meters, but simply have additional bonus options for measuring inductance, capacitance and transistor parameters.
3. You bought the LCR-T4 clone model, which has a very old Chinese mod firmware, in which so many important tests and calibration settings have been removed. Update the firmware on your clone, calibrate it as it should and then compare the readings hFE.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 26, 2020, 01:10:53 pm
No wonder that I haven't found any datasheet. It's an MPS2222A, and not an MPS222A as noted in your first post. The maximum hFE of the MPS2222A is 300. Yep, 425 is way off. And with indman's hint about the stripped-down and modified firmware I'd recommend to update your tester to one of the two genuine OSHW firmwares. After that you may blame us. >:D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stan21 on June 26, 2020, 07:20:02 pm
Stan21,
1. DMM is the common designation for Digital Multi Meter! It's a shame if you did not know these simple things before this time.
2. VC-9808, Mastech MAS345 - this is DMM! They are not specialized LCR meters, but simply have additional bonus options for measuring inductance, capacitance and transistor parameters.
3. You bought the LCR-T4 clone model, which has a very old Chinese mod firmware, in which so many important tests and calibration settings have been removed. Update the firmware on your clone, calibrate it as it should and then compare the readings hFE.
Don't do nitpicking, 9808 has iductance, capacitance and resistance, hense LCR and this is how it is positioned on a market; MAS345 does not have inductance so it is not LCR, 5828 is not digital so it is not 'DMM'. And _ANY_ of this has nothing to do with subject. It is a shame for you to wase the thread with off-topics.
You don't know this is 'old Chinese firmware' and your guess is just a wishfull thinking. And that exactly model from the same seller had positive review 5 years ago. https://hackaday.com/2015/04/24/review-transistor-tester, and also a very good rating on Amazon.
When I by a 'tester', I want to open the box, connect a battery and start testing instead of wasting time on browsing 250-pages for the search of 'genuine warranted Snark' that may or may not make that crappy gadget functional. Well, obviously that does not work for a cheap gizmo.
So you should be ashamed of your arrogant and biased attitude. Have a potato.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stan21 on June 26, 2020, 07:25:30 pm
No wonder that I haven't found any datasheet. It's an MPS2222A, and not an MPS222A as noted in your first post. The maximum hFE of the MPS2222A is 300. Yep, 425 is way off. And with indman's hint about the stripped-down and modified firmware I'd recommend to update your tester to one of the two genuine OSHW firmwares. After that you may blame us. >:D
Where is a link on 'two genuine OSHW firmwares' update instruction?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 26, 2020, 07:43:53 pm
Stan21,
I’ve seen a lot of trolls like you in my time, and I would send you for disrespect for the author’s work for a long time in the banned.
Without any arrogance and prejudice. ;)
Send a complaint about the tester to the seller from whom you bought it and there is no need to make a complaint here!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stan21 on June 26, 2020, 07:59:03 pm
Don't cry, lion! :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 26, 2020, 09:49:07 pm
Where is a link on 'two genuine OSHW firmwares' update instruction?

In case you're familiar with programming AVRs via ISP:
- https://github.com/madires/Transistortester-Warehouse (https://github.com/madires/Transistortester-Warehouse)
- or you could try a pre-compiled k-firmware at https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk) (mega328_T3_T4_st7565 or mega328_T4_v2_st7565).

FYI:
- For example, DER EE DE-5000 is an LCR meter. There are huge differences between an LCR meter and a DMM able to measure capacitance and inductance. The DMM won't let you select a test frequency and it won't give you the Q factor. As a beginner it's easy to fall for marketing hogwash.
- The firmware of the T4 tester is based on an old version of the k-firmware. Because of the limited flash size of the ATmega328 the vendor had to remove some code and features to be able to add fancy graphics.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stan21 on June 26, 2020, 11:18:44 pm
Where is a link on 'two genuine OSHW firmwares' update instruction?

In case you're familiar with programming AVRs via ISP:
- https://github.com/madires/Transistortester-Warehouse (https://github.com/madires/Transistortester-Warehouse)
- or you could try a pre-compiled k-firmware at https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk) (mega328_T3_T4_st7565 or mega328_T4_v2_st7565).
OK, so in brief, this model cannot be re-programmed without removing display, that is, without almost complete disassemble. And there is no proof that firmware update might help. And there is no warranty it won't brick after firmware replacement. Totally does not worth an effort.
Well, for my $15 I spent on this useless toy I had a lot of fun. Dumping.
Should I have asked you to lecture me about the semantic and definitions of 'LCR' term I should have thanked you  for the lot of totally useless details. Fortunately, I had not so I will not, sorry. But nice try, though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 27, 2020, 03:35:02 pm
Well, for my $15 I spent on this useless toy I had a lot of fun. Dumping.

 :clap:

Quote
Should I have asked you to lecture me about the semantic and definitions of 'LCR' term I should have thanked you  for the lot of totally useless details. Fortunately, I had not so I will not, sorry. But nice try, though.

 :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on June 27, 2020, 03:37:23 pm
@madires

Thanks for keeping your composure and trying to help. Unfortunately, not everyone can or wants to be helped. :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: Hydron on June 27, 2020, 05:21:46 pm
I'd like to second the thanks to the helpful people here, in particular madires and indman.

The fact I can go and buy such a useful instrument (and then improve it with the new firmware supplied here) for so little money is really amazing, and would be even more important for those starting off in electronics or with limited funds.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on June 27, 2020, 11:52:54 pm
So you should be ashamed of your arrogant and biased attitude.

you should be ashamed of subjecting people to your room temperature IQ.   :clap:
Title: Re: $20 LCR ESR Transistor checker project
Post by: pupa on June 28, 2020, 07:14:57 pm
Stan21,
1. DMM is the common designation for Digital Multi Meter! It's a shame if you did not know these simple things before this time.
2. VC-9808, Mastech MAS345 - this is DMM! They are not specialized LCR meters, but simply have additional bonus options for measuring inductance, capacitance and transistor parameters.
3. You bought the LCR-T4 clone model, which has a very old Chinese mod firmware, in which so many important tests and calibration settings have been removed. Update the firmware on your clone, calibrate it as it should and then compare the readings hFE.
Don't do nitpicking, 9808 has iductance, capacitance and resistance, hense LCR and this is how it is positioned on a market; MAS345 does not have inductance so it is not LCR, 5828 is not digital so it is not 'DMM'. And _ANY_ of this has nothing to do with subject. It is a shame for you to wase the thread with off-topics.
You don't know this is 'old Chinese firmware' and your guess is just a wishfull thinking. And that exactly model from the same seller had positive review 5 years ago. https://hackaday.com/2015/04/24/review-transistor-tester, and also a very good rating on Amazon.
When I by a 'tester', I want to open the box, connect a battery and start testing instead of wasting time on browsing 250-pages for the search of 'genuine warranted Snark' that may or may not make that crappy gadget functional. Well, obviously that does not work for a cheap gizmo.
So you should be ashamed of your arrogant and biased attitude. Have a potato.

What an arrogant and useless attitude. Yet you come here for help? What a total waste of this site's good will and recources to try and help someone like you!

What"s happening in your country seems to shine through very strongly in your attitude.

Farewell I hope.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on June 28, 2020, 08:54:17 pm
Agree. Public thanks to madires and indman for their endless patience with me.

I am not familiar with your slang and have no idea what 'DMM' is.

 :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: CatalinaWOW on June 29, 2020, 01:00:34 am
I am embarrassed to share a country with Stan21.  I am sure most recognize that in spite of the news reports his attitude is not the norm currently, and hopefully not for quite a ways into the future.

I have an early model of one of these testers, and am very pleased.  I use it more frequently than much of the brand name certified test gear that I own.   I follow this thread simply because I may be tempted to get a newer version and want to follow the options.

The patience of the supporters of this device is amazing to me.  They have continued to help people through thousands of questions, many repetitive, many of which deserved a seldom issued RTFM comment.  I salute them for their dedication and for the quality of the work they have performed. 

I also recognize the many, many who have shown their appreciation for the help they have been given.  They do represent the norm, not Stan21.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on June 30, 2020, 10:40:05 am
Cross-posted from my other thread for some good news....I'm slightly emotional!!  :-DD

---

Well. What a journey. Finally, I've managed to fix this and implement all of indman's recommended modifications. I went from not even knowing what flux was and not owning a DMM to replacing SMD components and hand-soldering wire onto IC pins!

Granted, I've almost destroyed the plastic housing through many errors with the hot soldering iron and the hot air gun, the board looks cr*ppy and the third port is barely usable, but it works!!! And I have 1.39m!!

It turns out the problem was with the eBay special USBAsp. I learnt how to use an Arduino as an ISP programmer with some online tutorials and hooked it up and it worked straight away.


Thanks to all who have contributed, esp indman and madires. Hopefully one day I can give something back to the project.

(https://i.ibb.co/qNmj52B/IMG-20200630-201840.jpg) (https://ibb.co/qNmj52B) (https://i.ibb.co/w68nXF4/IMG-20200630-224343.jpg) (https://ibb.co/w68nXF4)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 30, 2020, 12:33:22 pm
de_light, I congratulate you on this victory! :)
This is a great example of the fact that if a person wants to achieve a result and comes to the forum for help, then he receives this help and listens to the advice of other people.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 01, 2020, 03:00:31 am
Exactly, indman. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on July 01, 2020, 11:40:32 am
Question: can anyone help to explain why I am getting some very odd readings for ESR and capacitance with some old capacitors I am replacing?
(unit has been calibrated/adjusted and tested with other devices and reading well, e.g. ceramic caps and film resistors)

For example, I removed a huge, 40 year old 5600uF rated electrolytic cap. I consistently got readings of 7765uF with an ESR of 0.33, over multiple readings. This was out of circuit.

Then, I tested some 490uF caps in circuit and they came back over 600uF.


Is this a question of tolerances? Or do caps increase their capacitance as they age? I've no idea. :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 01, 2020, 01:11:30 pm
I've seen that too. I have a few 30+ years old electrolytics (Roederstein) from audio amp power supplies and they are still fine (checked with an LCR meter), just gained more than 20% capacitance. No idea why and how that happens. Most old Philips electrolytics of the same age are unusable (low capacitance, high ESR and some are also leaky).

If you measure caps in circuit there are usually other components in parallel. Since the tester measures capacitance via the charging time method any resistance in parallel will increase the charging time. Hence the larger capacitance value. The other components can also completely screw up the measurement, i.e. the tester aborts the measurement because of a timeout.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 01, 2020, 03:22:25 pm
Is this a question of tolerances? Or do caps increase their capacitance as they age? I've no idea. :-//
Yes, all these reasons can change the capacitance of a capacitor in a big way.
In addition, an increase in electrolytic capacitance can occur due to a change in the property of the dielectric, which causes a decrease in the quality factor of the capacitor.
But this effect can be detected only when measured with a quality LCR meter.
Another reason, as madires correctly noted, may be an increased leak in the capacitor itself, which will be considered by the tester as an increased capacity.Since the tester measures capacitance via the charging time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CatalinaWOW on July 01, 2020, 10:18:29 pm
While all of the bad reasons for these high capacitance values can be true, don't overlook the tolerance issue.  Spec tolerances on this type of capacitor are often 30 or 40%.  Quality suppliers would aim high since in the typical application high is good.  So most of what you are seeing could be just high value capacitors, with minor increases due to the other factors shown.

Pretty easy to check by just observing RC decay with a known resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 03, 2020, 08:11:42 pm
Have fun! :)

v1.40m
- Fixed error in SSD1306 driver which caused component symbols placed wrongly (reported by Andrei Paul).
- Changed avrdude configuration in Makefile to be more user friendly and to allow customized options.
- Added drivers for ILI9481 and ILI9486 based displays (8 and 16 bit parallel). Thanks to Bohu for providing an ILI9486 based display for testing.
- Fixed logic error for color displays when color feature is disabled.
- Added configuration switch for color displays to swap red and blue color channels (LCD_BGR).
- Improved R/L monitor to reduce spread of measurement values (reported by indman@EEVblog). Might not help in all cases.
- Fixed "#ifdef" issue for Display_HexByte() and Display_HexDigit() (reported by AlcidePiR2@EEVBlog).
- Support for ATmega 640/1280/2560. Thanks to Bohu for providing an Arduino Mega 2560 for testing.
- The detection of the rotation direction in ReadEncoder() was reversed. Changed to correct direction and updated settings in config_<MCU>.h and Clones.
- Fixed initialisation issue for hardware SPI. Also fixed some faults in SPI_WriteRead_Byte() and I2C_ReadByte() for bit-bang mode.
- Added alternative mode to Zener check in case the boost converter runs always or the circuit hasn't one (ZENER_UNSWITCHED, suggested by indman@EEVblog).
- Configuration switch for 100nF AREF buffer cap instead of 1nF to deal with some MCU boards (ADC_LARGE_BUFFER_CAP).
- Added alternative cyrillic fonts 8x16 (FONT_8X16ALT_WIN1251_HF) and 8x8 (FONT_8X8ALT_WIN1251_VF, thanks to indman@EEVblog).
- Updated Russian texts (thanks to indman@EEVblog).
- Option to use a manual power switch instead of the default soft-latching one (POWER_SWITCH_MANUAL).
- Added detection of two short presses of the center bar in ReadTouchScreen().
- Fixed fault in Touch_CharPos() regarding TOUCH_FLIP_X/TOUCH_FLIP_Y (reported by Bohu). 
- Replaced some ISO8859-2 fonts with updated versions provided by Bohu.
- Option for checking resistors for E series norm value (SW_R_E*). Also for capacitors (SW_C_E*) and inductors (SW_L_E*). Optional output of color code for resistors (requires color graphics display).

Available at https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 03, 2020, 08:50:11 pm
Lots of good stuff! It may be mundane, but I like the option to have a real power switch. ^-^

What kinds of functions are folks using a ATMega 2560 for?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 03, 2020, 09:14:06 pm
What kinds of functions are folks using a ATMega 2560 for?

Using the additional I/O pins for driving a 3.5" 320x480 display via 8 or 16 bit parallel bus. Anyhow, there are a lot of Arduino enthusiasts who prefer to do projects based on Arduini and won't touch "bare-bone" ATmega boards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bitseeker on July 03, 2020, 11:05:27 pm
Oh, bigger display. That's cool.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 04, 2020, 07:18:21 am
Have fun! :)
v1.40m
Another addition - the Clones file has been updated, configurations for BSideESR02 (DTU-1701) and Arduino Uno (Mega) 2560 have been added to it  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on July 04, 2020, 01:49:55 pm
Have fun! :)
v1.40m
Another addition - the Clones file has been updated, configurations for BSideESR02 (DTU-1701) and Arduino Uno (Mega) 2560 have been added to it  :)

Is there a precompiled v1.40m available for the BSideESR02?
Thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on July 04, 2020, 02:29:32 pm
Hello
search working HEX files and fuse settings for the GM328
Transistor Tester (from Banggood) because I have the Atmega
shot. The original seems to be protected against reading :-(
TX7014DH is on the O-Led, thanks for a feedback
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 04, 2020, 02:50:06 pm
Is there a precompiled v1.40m available for the BSideESR02?

If someone likes to support the project by providing precompiled firmwares for different clones I would upload them to the GitHub repo. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 04, 2020, 03:02:11 pm
search working HEX files and fuse settings for the GM328
Transistor Tester (from Banggood) because I have the Atmega
shot. The original seems to be protected against reading :-(
TX7014DH is on the O-Led, thanks for a feedback

Your tester is an AY-AT clone with an ST7735 based display and it's running the k-firmware (or a modified version). Please try mega328_color_kit (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)). The AY-AT is also supported by the m-firmware (see Clones files in the firmware archive). Fuse bits are lfuse 0xf7, hfuse 0xd9 and efuse 0xfc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 04, 2020, 03:18:37 pm
madires, You could not show in the photo what your firmware 1.40 looks for ILI9481 or ILI9486 Arduino Mega 2560?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 04, 2020, 04:45:38 pm
Since you're asking so nicely, Mega2560 with ILI9486 based display via 8 bit parallel bus:
[attach=1]
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 04, 2020, 04:55:38 pm
Madires Thanks for the photo, it looks great! I have a 3.5 display on the ILI9481 and Arduino Mega2560. I will try to repeat your design. ;)

Have fun! :)
v1.40m
- Option for checking resistors for E series norm value (SW_R_E*). Also for capacitors (SW_C_E*) and inductors (SW_L_E*). Optional output of color code for resistors (requires color graphics display).
This option can be very useful for many people, thanks madires! :-+
I looked at her work in Proteus and she looks very attractive. Only I did not find information on a series of E24 with a tolerance of 1%. The standard E24 series implies a tolerance of 5%. Can you explain this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on July 04, 2020, 04:57:58 pm
For madires.

New Spanish translation file with the latest additions.

Thanks and best regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 04, 2020, 05:47:32 pm
Thanks for the photo, it looks great! I have a 3.5 display on the ILI9481 and Arduino Mega2560. I will try to repeat your design. ;)

Please let me know if the ILI9481 driver works because I don't have such a display yet for testing. The ILI9481 is very similar to the ILI9486, just needs a different initialization. So the ILI9481 driver is basically a copy of the ILI9486 one with an adapted initialization.

This option can be very useful for many hams, thanks madires! :-+
I looked at her work in Proteus and she looks very attractive. Only I did not find information on a series of E24 with a tolerance of 1%. The standard E24 series implies a tolerance of 5%. Can you explain this?

It's an inofficial standard. Some E24 values are also part of E96, and some aren't. Several manufacturers added the missing E24 values to their E96 1% resistors (it's a mix of E96 and E24) because of customers' demand.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on July 06, 2020, 09:34:41 am
I'm trying to compile the 1.40m for BSIDE (as a first small thing to do for others!). I'm getting an avrdude: ERROR: address 0x8010 out of range at line 2049 of ComponentTester.hex error on the files that I am trying to load onto the tester.

Am I right in thinking this error means that the filesize is too large for the Atmel 328p internal memory?


Program size is 33064 bytes (100.9% full)
Data is 241 bytes

EEPROM 1026 bytes (100.2% full)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 06, 2020, 10:28:28 am
Yep, it exceeds the flash and EEPROM size of the ATmega328. To decrease the size simply disable a few features you don't really need.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on July 07, 2020, 09:17:31 am
For BSIDE ESR 02 tester 1.40m 8MHz and 16MHz

Has autohold enabled, 60s timeout

https://drive.google.com/file/d/1820dat2Fdzn6tY6CqapZ-QGmm6cjZYjO/view?usp=sharing (https://drive.google.com/file/d/1820dat2Fdzn6tY6CqapZ-QGmm6cjZYjO/view?usp=sharing)

(https://i.ibb.co/8Brw27L/IMG-20200707-195827.jpg) (https://ibb.co/8Brw27L) (https://i.ibb.co/D9hJ3pV/IMG-20200707-200312.jpg) (https://ibb.co/D9hJ3pV)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 07, 2020, 09:39:08 am
de_light,
there is no need to add ComponentTester, ComponentTester.lss and ComponentTester.map files to the archive contents. They are not needed for the programmer to work. It is more informative if you attach the config.h and config_328.h files to the archive, which contain information about the display settings and other options specific clone.  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on July 07, 2020, 06:27:01 pm
Hello
search working HEX files and fuse settings for the GM328
Transistor Tester (from Banggood) because I have the Atmega
shot. The original seems to be protected against reading :-(
TX7014DH is on the O-Led, thanks for a feedback
The picture in your post is of what's called an AY-AT around here, not GM328. And the AY-AT doesn't have an oled, but an LCD screen

Assuming you have an AY-AT with an LCD as in the picture you provided, it's identical to mine. My version was not protected, and I attached the files to this message https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg3085915/#msg3085915
Title: Re: $20 LCR ESR Transistor checker project
Post by: cz939 on July 07, 2020, 07:39:45 pm
Hi! Here are some observations and thoughts regarding a new T7/TC1 V2.12k tester. Have you experienced the same? Are there any good explanations and solutions?
Would like to know whether some problems regard just mine piece, or they are common for this lot/series or the old firmware. Maybe some are due to measuring circuit limitations or probing methods? Possibly some are corrected in new open software versions, but this is poor comfort.

Testing of resistor by means of all 3 leads, with 2 of them shorted gives us resistor array of some R and about 0Ω, obviously. But testing of a diode in the same way, or 3-terminal transistor with internal shortage, shows two almost identical diodes, what is of course wrong. Anybody knows why the shortage is not detected? A bug in the logic?

It's a pity that for resistor array/potentiometer the sum of two resistances is not calculated and displayed.

When measuring of transformer coils the first result can be small, the second and consecutive numbers are much much higher. After exchanging of test leads the situation repeats, similarly when measuring in mean time of another coils of the same transformer, if any. This is effect of magnetic hysteresis and DC magnetizing of core material. But which inductance result is correct? The higher? Maybe the probing sequence should de-magnetize (or slightly magnetize) the core prior the essential measurement(s)? And/or provide both numbers - for AC and DC?

Probably some of us noticed that serial resistance of inductors is sometimes showed e.g. about 140Ω whereas the real value is only a few ohms. This is huge error! But sometimes similar RL elements are measured intact. Strange.
Found a "by-pass" - connecting of small resistor (just 10-20Ω) in series with the measured coil corrects the results! The added resistance must be simply subtracted from displayed R, of course, not sure whether and how to adjust L.

Testers with factory (old) firmware suffer wrong measurement of bipolar transistor hFE and this is known behavior. It is probably caused by big relative error when measuring of small voltages or close to unstable VCC, comparable to ADC accuracy. Have no better explanation as hFE at low Uce (near saturation) is normally much smaller.
I think both measured hFE coefficients along with Ic currents and Uce voltages in common collector and common emitter configurations should be displayed (but there can be no space or memory). Or only for OE, if we know that measurements for OC stage are often worth not much.
Was trying to change transistor work point and measuring conditions by means of additional resistor. It turned out that such slight modification of measuring circuit can dramatically amend the results. By connecting of additional 100Ω in series with BJT collector we can get correct measurement of hFE coefficient!

Did someone manage to change the switch-off time after probing for TC1/T7 family testers with STC15L104W mcu? According to early instructions as well as provided on PCB it can be set to 10-15-20-25s respectively by means of P1 & P2 jumpers combination. How to set them? Just solder short to ground?
Default factory setting is 1-0 = 20s, however both points are left unconnected (open, at supply voltage) 1-1 = 25s. How it works? P1 & P2 pads are provided rather for ISP, and mask around is not scrapped/tinned (dislike EN pad).

The supply mcu works very unreliably - sometimes doesn't react on Start button, sometimes shuts everything off instead of initiating a new test and sometimes doesn't automatically switch the device off after 20-25s. And it resets itself during probing from time to time.
I wonder how the 3V (3.6~2.4V) STC15L104W supply mcu can work up to about 4.8V? Recommended replacement is W series (operating voltage 5.5~2.5V), but the older L chips were installed in T6/T7/TC1.
Guilty can be also noise from converter or poor FW. Blinking red dot may be accidentally observed, signalling false IR waves, even if there is no pilot used or the sensor window is covered.
Mystery transmissions between MCU's has not been probably decoded either.
However if for any reason meter doesn't switch off automatically or manually by long button pressing, it is switched off anyway after 160s from last start/restart.

What do you think (what could be the reasons) of different measurement results for the same part depending of test point/leads order, e.g. EBC=123 and EBC=321. This is for calibrated tester and in case of transistors, whereas for simple 2-leg elements the results are intact and steady. Is it an effect of some internal asymmetry and/or step-up converter noise or supply circuits instability?

Probably not everybody knows that 2.12 FW clones are "SW ready" for control of discharge relay. Unfortunately not HW and there is no place on PCB prepared for transistor, relay and clamping resistors.

Some manufacturers/distributors install/sell clones with poor quality or old accumulators, which are unable to supply testers in the whole 4.2-3.0V range. Low battery warning appears at 3.0V, but for some devices this is over strength - it resets, displays white screen, fades, squeaks - over and over again, until built-in protections switches it temporarily off or someone connects USB charging cable.
It even seems like some accumulators gradually discharge to about 3.3-3.2V, then the voltage suddenly jumps to 3.5V, but soon "dies" after couple tests. The truth is quite different - the battery voltage drops even more and it is unable to supply dc/dc booster and LDO, MCU supply voltage drops below 5V and all measurement results in such conditions are tricky - battery voltage looks higher, silicon transistors get 50uA Ice0 & Ices etc. After recharging of the battery the parts parameters "normalizes".
Isn't it strange that 1S 15C 350-450mAh LiPo battery behaves in such manner? What is such battery life span?
These series clones feature very high supply current and PS structure is inefficient. 3.7V accumulator voltage boost converted to 9.5V (and 35-45V for ZD), then linearly regulated to about 5V and one more time to 3.3V for LCD and LEDs.

The tester seems to be a simple one-button device - "just put-in something and push". Its measuring circuit has been designed to be simple too. Yet its operation is not so straight. Probing conditions can change in many ways and not all parameters are calculated and displayed. Moreover, the conditions often differ from those encountered in popular meters. One has always keep in mind complicated rules and formulas described in manual or at least schematics listed in the short version - ttinfo.
By the way, is there a more current version than the 1.11k KHK '2015 document? And official pdf of English 1.39 m ttester/ctester (I found "only" Latex files and some translations)?

Ordinary multi-meters are of better or less better accuracy (class), but are stable. In contrary, measuring results of "our" testers often scatter in consecutive probes (and still consistent for some simple elements). This is probably due to thermal and voltage instabilities as well as noise. Are other models without converter more stable?

The "instrument" is good for testing of discrete elements "from a drawer" but rather not those soldered on board. This is mainly due to its measuring principles and logic. It seems that almost any additional by-side resistances, capacitances or semiconductors render probing void.
Even a popular DMM with ohmmeter and diode test can be used for in-circuit measurement of resistors by means of low-voltage bridge as well as diodes with current source, but we select appropriate function and polarity. Tester is smart, but not for mixed parts. Maybe newer FW with menu which enables switching for selected-type cyclic measurement in addition to "universal" smart mode behaves better in such situations, but T7 has no menu.

The series is equipped with ZIP socket and cheap small spring hook clip wires - good for small THT parts but not suitable for larger terminals nor SMD. Especially lack of SMD pads (or adapter) sucks.

It seems all clones are equipped with too hard start-button. I think it might be much softer, like typical mouse click or roll. Maybe it is not so important when elements are mounted in socket or clips and you have free hands, but in cases you are using 2 or 3 test leads almost 4-th hand is needed to push such hard button.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 07, 2020, 08:48:05 pm
Please check out https://github.com/madires/Transistortester-Warehouse for the latest firmwares and documentation. See the Clones file in the m-firmware archive for TC-1 modifications to make the TC-x compatible with the OSHW firmwares. I think that the TC-x' boost converter in conjunction with poor filtering and an LM78L05 might be the cause for measurement values jumping around.
Title: Re: $20 LCR ESR Transistor checker project
Post by: all_repair on July 08, 2020, 10:14:19 am
May I know how does one interpret the Capacitor leakage reading?  of course, it is M version :D.  I am seeing charging current and voltage, and then discharging voltage.  They are happening quite fast.  I got no idea is the cap leakage is low, or not.  No delta T provided.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on July 08, 2020, 10:36:07 am
May I know how does one interpret the Capacitor leakage reading?  of course, it is M version :D.  I am seeing charging current and voltage, and then discharging voltage.  They are happening quite fast.  I got no idea is the cap leakage is low, or not.  No delta T provided.
https://raw.githubusercontent.com/madires/Transistortester-Warehouse/master/Documentation/English/ctester-1.40m.pdf (https://raw.githubusercontent.com/madires/Transistortester-Warehouse/master/Documentation/English/ctester-1.40m.pdf)

Page 30 of the manual talks about interpreting cap leakage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 08, 2020, 11:17:43 am
The measurement of the leakage current is basically the same as the k-firmware's Vloss measurement, and instead of the showing the voltage loss in % the voltage difference is converted into a leakage current. At the start of the measurement the cap's voltage is around 1.3V.

Quote
Another measurement taken is the self-discharge leakage current for capacitors larger than 4.7µF. It gives a hint about the state of an electrolytic cap. From my tests the typical value for a good electrolytic cap seems to be about:
  - 10-220µF    1-3µA
  - 330-470µF   4-5µA
  - 470-820µF   4-7µA
  - >1000µF     5-7µA per 1000µF
Title: Re: $20 LCR ESR Transistor checker project
Post by: cz939 on July 08, 2020, 03:53:51 pm
Hope this is proper topic for such discussions. Thank you for reply. The link to the well known content (still evolving) ensures there is no newer docs "hidden" somewhere else.

I've accused the converter ~1MHz PWM modulated signal, present probably almost everywhere in the device, as well as floating supply voltage, for most problems, but is the construction flaw the sole cause of all drawbacks?
Some testers cheep (like SW radio) under some circumstances (higher current, worse coil impregnation). Is it "normal" or worrisome symptom?
Are there any ways to improve screening, decoupling or filtering? Did anybody try to add one more tap (transformer rewind) for 3.3V or LED supply, or to replace some ICs?
Can someone give a positive example of TC1/T7 FW update - both MCUs, without STC15L "replacement"?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 08, 2020, 05:22:28 pm
I doubt that the TC-x can be improved greatly. So I'd recommend to get some other tester clone if you aren't happy with the TC-x' performance. Several users updated the STC15L with the alternative firmware at https://github.com/atar-axis/tc1-u4 to be able to run the OSHW firmwares.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on July 09, 2020, 11:55:55 am
Out of interest, what do you think is the best tester hardware going?
I doubt that the TC-x can be improved greatly. So I'd recommend to get some other tester clone if you aren't happy with the TC-x' performance. Several users updated the STC15L with the alternative firmware at https://github.com/atar-axis/tc1-u4 to be able to run the OSHW firmwares.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 09, 2020, 02:02:45 pm
There isn't any perfect tester unless you build one yourself. ;) If you are looking for a tester clone to buy it depends on what you want. The  AY-AT (AKA GM328A) is still is good choice. And If you want a nice case maybe the BSide ERS02 (DTU-1701). For checking crystals and measuring higher frequencies the Hiland M644 because it comes with the extended frequency counter. Unfortunately it lacks the input buffer stage for direct frequency measurement and a few bypass caps.

Things to know about the TC-x family:
- looks neat
- comes with the dreaded U4 with a high quiescent current
- noisy power circuitry
- not rarely do cheap parts in the power circuitry cause trouble (might have improved meanwhile)
- but they all do their job more or less
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on July 11, 2020, 04:15:44 pm
Hello Madires.
Today I had to check some JFET transistors, it recognizes them as the type of transistor they are but it does not show the pinout well, XGX appears.
I have tried other types of transistors and without problems.

The same happens with the firm of Trunk, although in this case if the names of the pins appear on the figure.
I'll see how to communicate it to see if it can be solved.

In Chinese GM328 and LCR-T4 meters without modifying it does not happen.

Is it possible to give him a solution, or for some reason he has to stay like this?

Thanks greetings.

(https://i.ibb.co/gR4FVV8/20200711-093725.jpg) (https://ibb.co/gR4FVV8)

(https://i.ibb.co/4mVyZYf/20200711-093357.jpg) (https://ibb.co/4mVyZYf)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 11, 2020, 04:58:49 pm
It's not a bug, it's a feature! :) For many JFETs it's hard to tell drain and source apart since they are nearly symmetrical. In those cases the k-firmware shows a "?" and the m-firmware an "x" for drain and source. Clones with an old k-firmware or modified version of an old k-firmware simply guess the pinout, i.e. it could be reversed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 12, 2020, 09:54:04 am
I edited the comparison table for the clones a bit! Fixed information about the display size in inches for some clones.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3088827/#msg3088827 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3088827/#msg3088827)
If you find errors in this table, please inform me in your personal mail.  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Ken333 on July 14, 2020, 12:27:23 am
On the model pictured below, what is the purpose of the 2 pads next to the power button?  It is the 2 pads above the trash can icon with the X over it.   I have searched for hours trying to find any reference to them.  But I did not find anything.  What are they for?
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on July 14, 2020, 01:13:55 am
https://1.bp.blogspot.com/-xE3AIF-ATh0/W90WYaLbjSI/AAAAAAAAAek/r5R8etcv9_MeKlOloMBoaat3NAgicMSTgCLcBGAs/s1600/WP_20181102_20_27_24_Pro.jpg]https://1.bp.blogspot.com/-xE3AIF-ATh0/W90WYaLbjSI/AAAAAAAAAek/r5R8etcv9_MeKlOloMBoaat3NAgicMSTgCLcBGAs/s1600/WP_20181102_20_27_24_Pro.jpg]https://1.bp.blogspot.com/-xE3AIF-ATh0/W90WYaLbjSI/AAAAAAAAAek/r5R8etcv9_MeKlOloMBoaat3NAgicMSTgCLcBGAs/s1600/WP_20181102_20_27_24_Pro.jpg (https://1.bp.blogspot.com/-xE3AIF-ATh0/W90WYaLbjSI/AAAAAAAAAek/r5R8etcv9_MeKlOloMBoaat3NAgicMSTgCLcBGAs/s1600/WP_20181102_20_27_24_Pro.jpg)

Looking at this image, it appears that these connect directly to the quartz crystal on the underside. Possibly for measuring the frequency of it for a troubleshooting application?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 14, 2020, 09:26:37 am
If you want to check the frequency of a quartz oscillator you would do that at the oscillator's output and not at the quartz because the additional load by a scope or whatever would change the frequency and might even cause the oscillator to stop running. But the XTAL1 pin can be also used as input for an external clock signal. Anyhow, those two pads are a little bit strange.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 14, 2020, 09:36:22 am
On the model pictured below, what is the purpose of the 2 pads next to the power button?
I would think that Chinese friends provided for the installation of a quartz resonator in a different form factor and on the side of the display. :)
Title: Ring Tester
Post by: pinguy on July 16, 2020, 05:48:09 am
This is an awesome tester, hats off to all involved in its development through the years!
Seeing all its great functions, I wonder if it could also have some sort of "ring tester" functionality (also known as Blue Ring Q Meter), to quickly find shorts in switching power supplies without desoldering the components, and also test various types of transformers for shorts.
Attached is the "classic" ring tester theory of operation, and schematic.
Can this be "emulated" some way with the ATmega? It would make this tool even more useful!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 16, 2020, 07:40:59 am
pinguy,
in some cases it is sufficient to measure the inductance of the suspect coil and, if possible, compare the result with a similar one. A transistor tester can easily do this. The photo shows a small experiment in which the inductance was measured with an artificially made short of 2 adjacent turns. The difference in results is obvious. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jleg on July 16, 2020, 10:07:58 am
Hi,

after quite a long time of successful usage i wanted to upgrade my beloved AY-AT tester, giving it a go with v1.40.
Since there were several recommendations for which tool chain to use, i made a little test.

I used good old WinAVR, AY-AT settings from "clones" file (with auto-powerdown, SW_SERVO, 30X32 symbols and the new E-series matching stuff for resistors), and replaced the tool chain binaries with

1) avr8 toolchain 3.4.5 (gcc 4.8.1)
was mentioned here some posts ago

2) avr8 toolchain 3.5.1 (gcc 4.9.2)
last one with gcc 4.x

3) avr8 toolchain 3.6.2 (gcc 5.4.0)
last one on microchip site

4) avr8 toolchain 3.6.2 + Arduino-IDE 1.8.13 avr binaries (gcc 7.3.0)
like 3), but with binaries replaced by IDE ones


TL;DR:
no. 4) did win  ^-^ - that variant created a binary with less than 100% size (ended up at 97.4% after disabling SW_PWM_SIMPLE, SW_SQUAREWAVE and SW_IR_RECEIVER). See details below. I also attached the binary for the AY-AT, perhaps it's useful for some.

Btw, with a cheap USBASP, using WinAVR is really easy. Just copy over the binaries; and if you add "make upload" (and "make fuses" if needed) in "Tools->Options->Tools", there's even no need to fiddle with avrdude or cli at all...  :)

And of course - thanks for all the efforts put into this firmware!

avr8 toolchain 3.4.5 (gcc 4.8.1)
AVR Memory Usage
----------------
Device: atmega328
Program:   33140 bytes (101.1% Full)
(.text + .data + .bootloader)
Data:        252 bytes (12.3% Full)
(.data + .bss + .noinit)
EEPROM:      793 bytes (77.4% Full)
(.eeprom)


avr8 toolchain 3.5.1 (gcc 4.9.2)
AVR Memory Usage
----------------
Device: atmega328
Program:   33278 bytes (101.6% Full)
(.text + .data + .bootloader)
Data:        252 bytes (12.3% Full)
(.data + .bss + .noinit)
EEPROM:      793 bytes (77.4% Full)
(.eeprom)


avr8 toolchain 3.6.2 (gcc 5.4.0)
AVR Memory Usage
----------------
Device: atmega328
Program:   33050 bytes (100.9% Full)
(.text + .data + .bootloader)
Data:        252 bytes (12.3% Full)
(.data + .bss + .noinit)
EEPROM:      793 bytes (77.4% Full)
(.eeprom)


avr8 toolchain 3.6.2 + Arduino-IDE 1.8.13 avr binaries (gcc 7.3.0)
AVR Memory Usage
----------------
Device: atmega328
Program:   32794 bytes (100.1% Full)
(.text + .data + .bootloader)
Data:        252 bytes (12.3% Full)
(.data + .bss + .noinit)
EEPROM:      793 bytes (77.4% Full)
(.eeprom)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pinguy on July 16, 2020, 09:36:30 pm
@indman that was a good test, thank you, and indeed there's an important difference in the reading of the shorted coils! BTW, is the Q value shown on display the same Q as in the blue ring Q meter? i.e. Q=10 means 10 "rings"? I couldn't find it mentioned anywhere in the manual.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 17, 2020, 05:53:10 am
BTW, is the Q value shown on display the same Q as in the blue ring Q meter? i.e. Q=10 means 10 "rings"?
The author of this measurement algorithm is Pieter-Tjerk de Boer(PA3FWM)!  ;)
Here http://www.pa3fwm.nl/technotes/tn11b.html (http://www.pa3fwm.nl/technotes/tn11b.html)
he briefly and easily explained the general principles works of the multitester and also explained his algorithm for measuring small capacitances and inductances by the resonance method.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pierreraymondrondelle on July 17, 2020, 08:50:21 am
Prominent piece of information. Thanks.

just a remark: remove the " \ " after html to make the link working.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 17, 2020, 12:48:59 pm
Hello everybody!
I offer all owners of the AY-AT clone as well as the GM328A black board clone a slightly modified version of the m-firmware 1.40m in English! I showed the functions that fit into the firmware in the photo. I have added some color coding for some important messages. ;)
You can download and check this firmware for 3 different processor frequencies - 8,16 and 20Mhz using the link from my resource https://yadi.sk/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke/English
If madires likes this mods, he can add it to his GitHub archive  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 17, 2020, 01:31:33 pm
The colored battery status is nice! If you send me a copy of the source I'll put it into the repo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: casinada on July 17, 2020, 08:31:29 pm
Nice  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on July 17, 2020, 09:16:08 pm
I like the resistor color bands. Gives you kind of an instant confirmation. Too bad I don't have a color lcd.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 18, 2020, 11:55:00 am
@timelessbeing you have a good incentive to build yourself such a device with a color display. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 18, 2020, 01:55:43 pm
I like the resistor color bands. Gives you kind of an instant confirmation. Too bad I don't have a color lcd.

Get an AY-AT/GM328A clone or build a tester with an ATmega644 and a large color display like 2.8" ILI9341 or 3.5" ILI9486. ;) 320x240 are ok with hardware SPI, but for 480x320 I'd strongly recommend the 8-bit parallel bus. And if you like to have a touch screen, choose a display with an ADS7843/XPT2046 touch screen controller (supported by the m-firmware). For the resistor color code enable SW_R_E24_5_CC, SW_R_E24_1_CC and/or SW_R_E96_CC. In case the colors aren't right you can adjust them in colors.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 19, 2020, 01:22:19 pm
Can you help clarify K-firmware SVN revision 819 (https://www.mikrocontroller.net/svnbrowser/transistortester?view=revision&revision=819):
Log Message: "LC frequency error with 20MHz"

Does it mean SamplingADC was not working with a 20Mhz quartz?

https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/sampling_lc.c?r1=819&r2=818&pathrev=819 (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/sampling_lc.c?r1=819&r2=818&pathrev=819)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 19, 2020, 01:49:03 pm
Can you help clarify K-firmware SVN revision 819 (https://www.mikrocontroller.net/svnbrowser/transistortester?view=revision&revision=819):
Log Message: "LC frequency error with 20MHz"
Does it mean SamplingADC was not working with a 20Mhz quartz?
No, it doesn't. SamplingADC worked, but incorrectly determined the frequency of the resonant circuit compared to the same measurement at 8 and 16 MHz.This error was reported by one of the participants in the Russian-language forum.
Karl-Heinz corrected this error for revision 819. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on July 24, 2020, 01:30:46 am
Hello together,

at the testing of new firmware m-1.40 with FONT_6x8_ISO8859_2_VF i missing the Caracter "µ" in both Display's (ST7565R). I have also tested with other languages - same result, without "µ".

[attachimg=1]

Sorry for bad english  ::).

Best regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 24, 2020, 10:01:55 am
at the testing of new firmware m-1.41 with FONT_6x8_ISO8859_2_VF i missing the Caracter "µ" in both Display's (ST7565R). I have also tested with other languages - same result, without "µ".

Open bitmaps/font_6x8_iso8859-2_vf.h, go to FontTable[] and look for:
Code: [Select]
  0xff,        /* 0x05 -> b5 */

Change that to:
Code: [Select]
  0x05,        /* 0x05 -> µ (micro) */

Thanks for reporting the issue! BTW, the latest version is 1.40m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 24, 2020, 10:12:42 am
madires,the same error with the symbol is in the font 6x8_ISO8859_2_V_F  font_8x12t_iso8859-2_vfp.h ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 24, 2020, 10:46:02 am
... and three more of the ISO8859-2 fonts. Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on July 24, 2020, 07:47:27 pm
Hello,

... not all Problems are so easy, thank you madires!

[attach=1]

Best regards, Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: xyz on July 25, 2020, 04:31:29 pm
Hi,

I followed your instructions but when I ran the command, I get the following error (towards the end of an otherwise successful run):
Code: [Select]
Reading | ################################################## | 100% 0.02s

avrdude: verifying ...
avrdude: 1 bytes of hfuse verified
avrdude: reading input file "0x04"
avrdude: writing efuse (1 bytes):

Writing |                                                    | 0% 0.00s ***failed;
Writing | ################################################## | 100% 0.05s

avrdude: 1 bytes of efuse written
avrdude: verifying efuse memory against 0x04:
avrdude: load data efuse data from input file 0x04:
avrdude: input file 0x04 contains 1 bytes
avrdude: reading on-chip efuse data:

Reading | ################################################## | 100% 0.02s

avrdude: verifying ...
avrdude: verification error, first mismatch at byte 0x0000
         0xfc != 0x04
avrdude: verification error; content mismatch

avrdude: safemode: efuse changed! Was 4, and is now fc
Would you like this fuse to be changed back? [y/n] Y

Any idea why it is complaining of mismatch and how to resolve this?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on July 25, 2020, 06:11:59 pm
@ xyz
get the latest version of AVRDUDE

http://savannah.nongnu.org/bugs/?45115 (http://savannah.nongnu.org/bugs/?45115)
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on August 04, 2020, 04:17:03 am
 Gift from China arrived.

(https://i.ibb.co/8659dh0/IMG-20200804-141502.jpg) (https://ibb.co/8659dh0)

Is this possible to reprogram with custom firmware? Can't see any ICSP headers anywhere.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 04, 2020, 07:06:30 am
Yes. I think that the location of the ICSP contacts will be similar to this option in the photo. But to be sure, you need to check each connection according to the standard connection diagram for the ATMega328 processor. Where to find the firmware for your clone, I already wrote in this message
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3088827/#msg3088827 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3088827/#msg3088827)
Title: Re: $20 LCR ESR Transistor checker project
Post by: joshto on August 04, 2020, 03:58:39 pm
First I want to say Bravo to the authors, amazing project. I've just bought a couple of clones, TC1 specifically, modded with a 22uF low esr cap and swapped mcu with a 644pa. Flashed u4 alt firmware, compiled and flashed of course the 1.40m on it. Seems that works very well.
I've bought it mainly for selectioning jfets. It shows Idss, coherent with a manual measure, but it's the only measure it give me. An important measure for jfets is Vgs(off), there is a way to show this value?
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 04, 2020, 04:29:28 pm
No idea, but I'll investigate if there's a way to measure Vgs(off) with the Transistortester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on August 04, 2020, 11:09:23 pm
 Thanks. The pinouts were the same. Flashed the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on August 05, 2020, 12:12:18 pm
Hi!
I compiled the English firmware of m-firmware v1.37m for a clone of AY-AT(GM328A) for 3 clock rates 8,16 and 20 MHz.
Once again great gratitude of madires for its work! :-+
The link for downloading of firmwares here in my storage
https://yadi.sk/d/yW8xa5NJgUo5z/M328Kit+TFT/Firmware/Markus Reschke/English (https://yadi.sk/d/yW8xa5NJgUo5z/M328Kit+TFT/Firmware/Markus Reschke/English)
ATMega328 do not have enough memory any more for all options which were made by madires therefore on a photo I showed the menu of functions which were located in the processor memory.
Also I added into the storage an original firmware from a clone of LCR-TC1 which it was succeeded to read to one of participants of a forum
https://yadi.sk/d/yW8xa5NJgUo5z/LCR%20%D0%A2%D0%A1-1/Firmware/Original (https://yadi.sk/d/yW8xa5NJgUo5z/LCR%20%D0%A2%D0%A1-1/Firmware/Original)

Hi Indman. I tried the original tc1 firmware you linked and it does indeed work  :-+ I am curious though about U4 original firmware as the program software doesn't appear to have a read function? can it be read or backed up or is it encrypted? Thanks..
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 05, 2020, 01:27:10 pm
The "U4" MCU doesn't support reading the current firmware, only writing a new firmware is possible. It's designed that way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: joshto on August 05, 2020, 02:11:06 pm
No idea, but I'll investigate if there's a way to measure Vgs(off) with the Transistortester.

In the k-firmware documentation ttester-1.13k.Bohu.pdf at page 77 there is this:
Quote
For JFET transistors often the characteristic current Idss is specified, the current in the drainwhen the gate-source voltage is 0V.  Here, however, the current is given by a 680 Ω load resistance atthe source side of the JFET. The load resistor generates a reverse voltage Vgs, which is also shown.With a 470kΩ load resistor at the source side of the JFET the Source-Drain current will be nearlyzero.   With  this  circuit  we  can  get  the  Gate-Source  Cutoff  voltage  Vgs_off  exactly  enough,  if  thevoltage remain below 5V.  With this two operating points we can estimate the current Igss with thenearly quadratic characteristic curve of the current.  If the estimated current Idss stay below 40mA,a additional measurement is done without a additional resistor at the source pin.  With the measuredvoltage at the source pin we can compute a additional current value.  Now we can compute a betterestimated current Idss with this higher current valued, the gate-source voltage and with the knownquadratic current curve, if the value of 40mAis not exeeded.  Due to the symmetrical design of theJFET transistors, the drain and source can not be distinguished.

So I think it's feasible
Title: Re: $20 LCR ESR Transistor checker project
Post by: jellytot on August 05, 2020, 02:44:48 pm
The "U4" MCU doesn't support reading the current firmware, only writing a new firmware is possible. It's designed that way.

Thanks madires. So no easy way to go back to original if i use the modified firmware unless I keep original u4 and either program a new one or modify the hardware ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 05, 2020, 04:20:36 pm
jellytot,the easiest way is to buy some more clean U4 chips and keep the original one. Soldering them is easy, so you always have a choice. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 05, 2020, 07:45:59 pm
In the k-firmware documentation ttester-1.13k.Bohu.pdf at page 77 there is this:
Quote
For JFET transistors often the characteristic current Idss is specified, the current in the drainwhen the gate-source voltage is 0V.  Here, however, the current is given by a 680 Ω load resistance atthe source side of the JFET. The load resistor generates a reverse voltage Vgs, which is also shown.With a 470kΩ load resistor at the source side of the JFET the Source-Drain current will be nearlyzero.   With  this  circuit  we  can  get  the  Gate-Source  Cutoff  voltage  Vgs_off  exactly  enough,  if  thevoltage remain below 5V.  With this two operating points we can estimate the current Igss with thenearly quadratic characteristic curve of the current.  If the estimated current Idss stay below 40mA,a additional measurement is done without a additional resistor at the source pin.  With the measuredvoltage at the source pin we can compute a additional current value.  Now we can compute a betterestimated current Idss with this higher current valued, the gate-source voltage and with the knownquadratic current curve, if the value of 40mAis not exeeded.  Due to the symmetrical design of theJFET transistors, the drain and source can not be distinguished.

So I think it's feasible

Yep, as long as V_GS(off) doesn't exceed 4.7 or 4.8V. I'll add it to my to-do list.
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on August 06, 2020, 05:02:16 am
4) avr8 toolchain 3.6.2 + Arduino-IDE 1.8.13 avr binaries (gcc 7.3.0)
like 3), but with binaries replaced by IDE ones

I am trying to set up my Win10 laptop  and was wondering which folder the binaries are located. These two have similar named folders. The second has more files.

1? C:\Program Files (x86)\Arduino\hardware\tools\avr\lib\gcc\avr\7.3.0
2? C:\Program Files (x86)\Arduino\hardware\tools\avr\avr\lib
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on August 07, 2020, 07:39:15 pm
Hello,

I bought two testers from Aliexpress. I tried to change the firmware on the first one in november already and posted my problems here (http://).


Cos I haven't so much time I bought a second one and tried to update this one. But it will also not work. :( What I have:

TC1 - 644PA inside - which I already tried in november to get working. MLCCs, diodes and measurement Rs (to 0,1%) changed, U4 successfully flashed.
Tester powers on, makes one measurement and powers off. Powers off so fast, that's not possible to read the result. As I described in my old postings. Same with v1.40

T7 - 344PA inside - HW ist china factory, no MLCCs or something else changed. U4 successfully flashed.
If there is no part in it, tester did not find any part (which is correctly) and restarts automatically a new measurement. This will be done 5 times and power off.
If there is any part in it (e.g. a C), tester starts to measure, shows result for some secons and will repeat measurment like a loop. It will never stop. Only if part is removed (then it will try only 5 times like no part at the beginning) or battery is empty.


For both testers config files are the same. Only change is the µC type in makefile. Other settings where copied from "clones".


Fuses on TC1 und T7 were different. But I can't remember how it was. I wrote the same fuses for both tester accidentally.
Now it is:

L: 0xFF
H: 0xD7
E: 0xFD (change like it is written in "clones")
LB: 0x3F

Any tips for me?  :-//

Regards
Chris
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 07, 2020, 08:23:23 pm
TC1 - 644PA inside - which I already tried in november to get working. MLCCs, diodes and measurement Rs (to 0,1%) changed, U4 successfully flashed.
Tester powers on, makes one measurement and powers off. Powers off so fast, that's not possible to read the result. As I described in my old postings. Same with v1.40

That's what the original firmware of U4 does. Presumably the reflashing of U4 went wrong.

T7 - 344PA inside - HW ist china factory, no MLCCs or something else changed. U4 successfully flashed.
If there is no part in it, tester did not find any part (which is correctly) and restarts automatically a new measurement. This will be done 5 times and power off.
If there is any part in it (e.g. a C), tester starts to measure, shows result for some secons and will repeat measurment like a loop. It will never stop. Only if part is removed (then it will try only 5 times like no part at the beginning) or battery is empty.

Either start the tester with a long key press (>0.3s) or enable UI_AUTOHOLD in config.h. It's explained in the README (and the German version README.de).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on August 08, 2020, 05:34:48 am
TC1 - 644PA inside - which I already tried in november to get working. MLCCs, diodes and measurement Rs (to 0,1%) changed, U4 successfully flashed.
Tester powers on, makes one measurement and powers off. Powers off so fast, that's not possible to read the result. As I described in my old postings. Same with v1.40

That's what the original firmware of U4 does. Presumably the reflashing of U4 went wrong.

Thanks for your reply. If I start the tester with a longer press it will make just one measurement. Later I'll check the readme again.

TC1

I flashed U4 again. But still the same. See the attached logfile. For me everything is looking fine. :(

Code: [Select]
Checking target MCU ...
  MCU type: STC15L104W
  F/W version: 7.2.5Q

Current H/W Option:
  . Current system clock source is internal IRC oscillator
  . IRC frequency: 11.999MHz
  . Wakeup Timer frequency: 26.419KHz
  . Do not detect the level of P3.2 and P3.3 next download
  . Power-on reset, use the extra power-on delay
  . RESET pin behaves as I/O pin
  . Reset while detect a Low-Voltage
  . Thresh voltage level of the built-in LVD : 2.42 V
  . Inhibit EEPROM operation under Low-Voltage
  . Hardware do not enable Watch-Dog-Timer
  . Watch-Dog-Timer pre-scalar : 256
  . Watch-Dog-Timer stop count in idle mode
  . Program can modify the Watch-Dog-Timer scalar
  . Do not erase user EEPROM area at next download
  . Do not control 485 at next download
  . Do not check user password next download
  . TXD is independent IO
  . TXD pin as quasi-bidirectional mode after reset
  . P3.3 output HIGH level after reset
  . Testing time: 2018-6-28

  . MCU type: STC15L104W
  F/W version: 7.2.5Q

Adjusting frequency ... [0.750"]
Adjusted frequency: 11.999MHz (-0.010%)

Re-handshaking ... Successful [0.125"]
Current Baudrate: 38400
Erasing MCU flash ...  OK ! [0.343"]
MCU ID : F2D4246E1A6F8E
Programming user code ... OK ! [2.171"]
Programming OPTIONS ... OK ! [0.047"]

H/W Option upgrade to:
  . Current system clock source is internal IRC oscillator
  . IRC frequency: 11.999MHz
  . Do not detect the level of P3.2 and P3.3 next download
  . Power-on reset, use the extra power-on delay
  . RESET pin behaves as I/O pin
  . Reset while detect a Low-Voltage
  . Thresh voltage level of the built-in LVD : 2.42 V
  . Inhibit EEPROM operation under Low-Voltage
  . Hardware do not enable Watch-Dog-Timer
  . Watch-Dog-Timer pre-scalar : 256
  . Watch-Dog-Timer stop count in idle mode
  . Program can modify the Watch-Dog-Timer scalar
  . Do not erase user EEPROM area at next download
  . Do not control 485 at next download
  . Do not check user password next download
  . TXD is independent IO
  . TXD pin as quasi-bidirectional mode after reset
  . P3.3 output HIGH level after reset

  . MCU ID : F2D4246E1A6F8E
  . MCU type: STC15L104W
  F/W version: 7.2.5Q

  . Set frequency: 12.000MHz
  . Adjusted frequency: 11.999MHz
  . Trim error: -0.010%


  Complete !(2020-08-08 07:25:25)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 08, 2020, 01:54:00 pm
The TC-1 has two special pads for solder bridges to set the power-off time (P1/P2). If you select the maximum time does the TC-1 stay on for a few seconds more? If so, the original firmware is still running. Or if you have a scope you can probe PD2 (or was it PD1?). When powering on U4 sends some data to the ATmega. Again, only the original firmware does that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on August 08, 2020, 06:02:24 pm
Thanks, I'll check it. To check signal on PD1/PD2 ist also no problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on August 08, 2020, 07:40:51 pm
I checked PD1/PD2 with a scope. No signals, only level changes.

PD2 changed from 2,8V to 4.8V after switching on. PD1 from 3.0V to 0V. And both back after power off.

And also no effect if P1 + P2 is connected to GND or VCC. Time is still the same.  :-//

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 09, 2020, 08:53:44 am
TC1 - 644PA inside - which I already tried in november to get working. MLCCs, diodes and measurement Rs (to 0,1%) changed, U4 successfully flashed.
Tester powers on, makes one measurement and powers off. Powers off so fast, that's not possible to read the result. As I described in my old postings. Same with v1.40

Do not be offended, but you have not been able to solve your problem for almost a year.
Have you tried the alternative 2-transistor control scheme that madires suggested?
It is assembled from simple parts in almost 30-60 minutes.
Can you access the menu on this firmware? You need to run hardware tests to help identify potential problems.
Show a photo of your tester board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 09, 2020, 10:35:26 am
I checked PD1/PD2 with a scope. No signals, only level changes.

PD2 changed from 2,8V to 4.8V after switching on. PD1 from 3.0V to 0V. And both back after power off.

And also no effect if P1 + P2 is connected to GND or VCC. Time is still the same.  :-//

In that case the new U4  firmware should be running. The m-firmware can be configured to run just one probing cycle and then power off by setting CYCLE_MAX to zero (default is 5). What are your settings for CYCLE_DELAY, CYCLE_MAX and POWER_OFF_TIMEOUT?
Title: Re: $20 LCR ESR Transistor checker project
Post by: aristarchus on August 09, 2020, 09:35:22 pm
Hi,

Got a GM328A with 1.12k and wondering how can I upgrade its firmware.

Is there a compiled 1.40m firmware for this so I could flash it?
Or, is there any document on how to compile the sources and get the flash files from this repository?
https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware (https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware)

Alternatively I see this one but I am not sure if it is a 1.40m
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_GM328/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_GM328/)
Is this 1.40m?


P.S.
Never mind about how to compile, found this post that gives the steps
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926)

Spoke too soon, tried it but got errors so back to square one.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on August 10, 2020, 09:29:46 am
I checked PD1/PD2 with a scope. No signals, only level changes.

PD2 changed from 2,8V to 4.8V after switching on. PD1 from 3.0V to 0V. And both back after power off.

And also no effect if P1 + P2 is connected to GND or VCC. Time is still the same.  :-//

In that case the new U4  firmware should be running. The m-firmware can be configured to run just one probing cycle and then power off by setting CYCLE_MAX to zero (default is 5). What are your settings for CYCLE_DELAY, CYCLE_MAX and POWER_OFF_TIMEOUT?

Config is exactly the same as on T7 and T7 doesn't make any problems. I'll check HW again.

What do you think about replacing 78L05 to MCP1703? Will the measurement more accurate?
I already replaced 680R and 470k to 0,1%.

If MCP1703 is assembled just need to comment #define HW_REF25 or anything else?
Title: Re: $20 LCR ESR Transistor checker project
Post by: aristarchus on August 10, 2020, 09:47:13 am
Hi,

Got a GM328A with 1.12k and wondering how can I upgrade its firmware.

Is there a compiled 1.40m firmware for this so I could flash it?
Or, is there any document on how to compile the sources and get the flash files from this repository?
https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware (https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware)

Alternatively I see this one but I am not sure if it is a 1.40m
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_GM328/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_GM328/)
Is this 1.40m?


P.S.
Never mind about how to compile, found this post that gives the steps
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926)

Spoke too soon, tried it but got errors so back to square one.


Ok, finally managed to be able at least to compile the 1.40m from here, (used a virtualbox XP since in my W10 I could not)
https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware (https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware)

But now I'm faced with a more daunting task, to identify what settings are needed for the GM328A .

Are the exact settings for the GM328A (config.h, config_328.h) known or anyone done this before and can help here?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on August 10, 2020, 09:50:01 am
Hi,

Got a GM328A with 1.12k and wondering how can I upgrade its firmware.

Is there a compiled 1.40m firmware for this so I could flash it?
Or, is there any document on how to compile the sources and get the flash files from this repository?
https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware (https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware)

Alternatively I see this one but I am not sure if it is a 1.40m
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_GM328/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_GM328/)
Is this 1.40m?


P.S.
Never mind about how to compile, found this post that gives the steps
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926)

Spoke too soon, tried it but got errors so back to square one.


Ok, finally managed to be able at least to compile the 1.40m from here, (used a virtualbox XP since in my W10 I could not)
https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware (https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware)

But now I'm faced with a more daunting task, to identify what settings are needed for the GM328A .

Are the exact settings for the GM328A (config.h, config_328.h) known or anyone done this before and can help here?

Check "clones" file for GM328 settings adn readme file also. :)
Compiling on win10 also works very well. I use WinAVR-20100110-install and need to replace msys-1.0.dll like on Windows Vista
Title: Re: $20 LCR ESR Transistor checker project
Post by: aristarchus on August 10, 2020, 10:00:41 am
Check "clones" file for GM328 settings adn readme file also. :)

Thanks,
I have already seen the clones text, it does not have the exact GM328A.
And it looks to me that to out the proper settings there the schematic is needed, does anyone got the exact GM328A schematic?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on August 10, 2020, 10:20:59 am
Check "clones" file for GM328 settings adn readme file also. :)

Thanks,
I have already seen the clones text, it does not have the exact GM328A.
And it looks to me that to out the proper settings there the schematic is needed, does anyone got the exact GM328A schematic?

What's different?

Maybe this one fits to your tester?
https://dragaosemchama.com/en/2019/04/gm328a-reverse-engineering-new-firmware-and-tetris/
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 10, 2020, 10:28:45 am
What do you think about replacing 78L05 to MCP1703? Will the measurement more accurate?

The MCP1703 is a good choice because of it's 0.4% tolerance and the higher output current. What really matters is that the voltage regulator delivers a stable voltage. The exact output voltage isn't that important since you can measure it and set it in config.h.

If MCP1703 is assembled just need to comment #define HW_REF25 or anything else?

Yep, that will disable the external voltage reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: aristarchus on August 10, 2020, 11:30:50 am

Maybe this one fits to your tester?
https://dragaosemchama.com/en/2019/04/gm328a-reverse-engineering-new-firmware-and-tetris/

Yes, that is the one.
Have seen this before but it looks to me that the author has problems in the schematic, he has interchanged the lines FREQ with VOLTMETER, at least from what I've seen and I do not know if he has other errors in his reverse engineering.
(My error, after seeing it again looks it is ok)

Anyway, I hope that someone has the exact GM328A settings and give a help here and save me the trouble.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on August 10, 2020, 11:37:28 am
Thanks, I'll order MCP1703. MCP1703 can be ordered in SOT-223 packe, which is pin compatible, but a littlebit bigger, to TO-89 LDO in TC1. TO-89 MCP1703 has got a different pinout.

Still one questions/sugesstion
I tried to test a brand new RGCL60TS60GC11. Only Diode is recordnized. I guess gate voltage is to low to switch the IGBT on?
What do you think about an small adapter PCB for testing IGBTs with higher gate voltage (even 15V ones). Higher voltage can be taken from boost converter and adjusted thru a e.g. LM317.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on August 10, 2020, 12:47:57 pm
@aristarchus

... the entry in clones-list is the first:

DIY Kit "AY-AT"

Regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 10, 2020, 05:10:38 pm
Still one questions/sugesstion
I tried to test a brand new RGCL60TS60GC11. Only Diode is recordnized. I guess gate voltage is to low to switch the IGBT on?
What do you think about an small adapter PCB for testing IGBTs with higher gate voltage (even 15V ones). Higher voltage can be taken from boost converter and adjusted thru a e.g. LM317.

Possibly, any semiconductor which needs more than 5V or 7mA can't be detected. Many users suggested similar ideas and the answer is that we like to keep the circuit simple. Adding support for higher voltages and currents would require an external switching matrix and would make the tester more complex and expensive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on August 10, 2020, 06:54:55 pm
You, and also Karl-Heinz, make a great job and I like the transistortester very much. The TC1 is my second Tester. My first one was built in 2013, long time before Chinese built it in a thousand  and I still use it, like it and love it:)

IMHO over this long time electronic has changed. More and more power electronics come to our homes. Almost every new device you buy in your household has got inverters, many many Tools and many many more. So maybe the Tester needs an update for power electronics too ?! :o

Keep it simple is good. I like it. But what do you thing about an adapter PCB like it is for testing optocouplers. A small PCB with additional electronic which will be pluged in the texttool socket and even has got an own socket?

On this PCB is a selectable voltage source for different gate voltages, powered from the boost converter. Selection has to be done manually, e.g. with a DIP switch. The tester will not trigger the device under test directly, it will trigger an additional transistor (bosster/driver stage). This transistor will power the gate of the DUT and you can measure lot's of values. This will be possible with any tester which has got and boost for Z-Diode testing. You have to calibarate this PCB before to know the characteristics of the booster.

Of course there are also some disadvantages, e.g. you need to know which pin is Gate, etc.

But it is a step in the right direction :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on August 11, 2020, 10:43:59 am
here you have some tested files
of course, recompile with your crystal frequency, I have 16Mhz version hex/eep files.
just change extension for ComponentTester - Copie.hex into ComponentTester.eep.
regards,pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: aristarchus on August 11, 2020, 12:58:36 pm
here you have some tested files
of course, recompile with your crystal frequency, I have 16Mhz version hex/eep files.
just change extension for ComponentTester - Copie.hex into ComponentTester.eep.
regards,pierre

Thank you.
The board here has 8MHz crystal, can I just remove the old one and simply install instead a new 16MHz crystal?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 11, 2020, 01:39:53 pm
Keep it simple is good. I like it. But what do you thing about an adapter PCB like it is for testing optocouplers. A small PCB with additional electronic which will be pluged in the texttool socket and even has got an own socket?

On this PCB is a selectable voltage source for different gate voltages, powered from the boost converter. Selection has to be done manually, e.g. with a DIP switch. The tester will not trigger the device under test directly, it will trigger an additional transistor (bosster/driver stage). This transistor will power the gate of the DUT and you can measure lot's of values. This will be possible with any tester which has got and boost for Z-Diode testing. You have to calibarate this PCB before to know the characteristics of the booster.

Of course there are also some disadvantages, e.g. you need to know which pin is Gate, etc.

I think a good idea would be to design a tester especially for power semiconductors. With the ability to limit currents/voltages it should be possible to detect pinouts as the Transistortester does. After detecting the component high current/voltage checks could be performed to measure the component's parameters. An addon adapter doesn't make much sense because you also need an additional power supply. A 9V battery isn't able to power that. So it's more reasonable to have a Power-Transistortester with everything included.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 11, 2020, 01:41:41 pm
The board here has 8MHz crystal, can I just remove the old one and simply install instead a new 16MHz crystal?

Yep, and no need to update the fuse bits.
Title: Re: $20 LCR ESR Transistor checker project
Post by: aristarchus on August 11, 2020, 02:06:59 pm
The board here has 8MHz crystal, can I just remove the old one and simply install instead a new 16MHz crystal?

Yep, and no need to update the fuse bits.

Ok, thanks!
Will go and get a 16MHz to replace.

One more question.
I did manage to have the compile ok with various settings.
Also I perform the programming for the Atmega238P with a AVRDragon under the AVRStudio tools, I use the eep & hex files produced from the previous compilation and I put fuses as E=0xFC H=0xD6 L=0xF7.

The problem is that I can flash with plain ISP method only new/blank 328P chips, if I flash them and put the fuses as above I can re-programm them only with parallel/HVPP programming and not with ISP.
Can I do something so to re-program the Atmega328P with plain ISP method?


/Edit: Is it something from the fuses that can be tweaked?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 11, 2020, 05:59:57 pm
Please try H=0xD9.
Title: Re: $20 LCR ESR Transistor checker project
Post by: aristarchus on August 12, 2020, 11:37:35 am
Yes, is is 0xD9 (sorry, obviously I mistyped above) and it does not allow ISP on a already programmed chip.
No problem anyway, I can reflash with HVPP, it just needs 20 or so cables but it does the job.

Found the reason for this, I do remove the atmega328p chip from its board and place it on the AvrDragon to flash it, whereas that is ok in other situations, it should not be done when the fuses are set to have external crystal..
Title: Re: $20 LCR ESR Transistor checker project
Post by: perieanuo on August 12, 2020, 03:55:07 pm
here you have some tested files
of course, recompile with your crystal frequency, I have 16Mhz version hex/eep files.
just change extension for ComponentTester - Copie.hex into ComponentTester.eep.
regards,pierre

Thank you.
The board here has 8MHz crystal, can I just remove the old one and simply install instead a new 16MHz crystal?
hi, of course you can put 16MHz crystal.Chances are the crystal's capacitors will work, if not just change them with those indicated in crystal's datasheet.
normally like madires said keep the correct fuses and it works by isp, I use only isp method.
my fuses are lfuse=0xF7 hfuse=0xD9 efuse=0xFC (or 04) and FF for lockbyte on my 16MHz AY-AT tester
best regards, pierre
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on August 13, 2020, 12:53:13 pm
Hi friends,
which version LCR meter is actually best? This from Reply #6352? I have LCR-T4 and LC-100A but LC-100A is very bad, I replaced inductor but isn't better so the version indman has?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 13, 2020, 02:27:15 pm
There's a common misunderstanding about the Transistortester being an LCR meter. It isn't, but it can measure L, C and R within some limits, and the k-firmware's SamplingADC function allows to measure also low value L/Cs. Inexpensive LC meters like the LC-100A are basically a simple LC oscillator plus a frequency counter. The Transistortester is presumably a little bit more accurate for capacitors above 1µF. Proper LCR meters, for example DER-EE DE-5000, apply an AC signal and measure voltage and current.

The AY-AT/GM328A is a nice general purpose Transistortester clone. However, I'd recommend to get a proper LCR meter if the LC-100A doesn't work for you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 13, 2020, 03:38:31 pm
Hi friends,
which version LCR meter is actually best?

I fully support the madires' thoughts on LCR! I have a quality DE-5000, but not as an advertisement, I also want to draw your attention to an affordable DIY kits LCR-bridge XJW01, which I use quite often and which in some cases is more convenient in terms of observing the measurement results. Sorry that may have deviated from the topic on the transistor tester. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on August 13, 2020, 04:23:30 pm
Ok but AY-AT/GM328A not test Zener diode wright? You have right about this basic projects as LC meters. I look one of this: PINTEK LCR-900 and have next question, what is difference between measure L, C, with professional LCR meter 100kHz freq. and e. g. 10MHz, difference is in measuring accuracy on smallest values L and C?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 14, 2020, 01:14:43 pm
The frequency of the AC test signal has an impact on the measurement range and the 100kHz are a common frequency for measuring a capacitor's ESR. If you have questions about specific LCR meters or about which one to choose please start a new thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chuck Norris on August 14, 2020, 02:14:05 pm
Hi! Thank you and congrats for this cool firmware!
I've installed the 1.40m on my T7 and it works very well.

I'm running into a small problem tho:
When it shuts down after the timeout, and when I turn it back on, it's stuck on "Bye!"
I have to remove the battery to turn it on again.
Any idea of where it's coming from? It doesn't happen when I manually turn it off.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 14, 2020, 03:59:10 pm
Could be a problem with the power control, i.e. the MCU keeps running. Have you reprogrammed U4 or are you using the hardware mod?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chuck Norris on August 14, 2020, 04:10:45 pm
I've reprogrammed U4
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 14, 2020, 07:11:40 pm
Does PD2's level change to low when the tester switches off?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chuck Norris on August 14, 2020, 07:32:44 pm
yes, PD2 is
high when I turn on the tester
low when it shuts down
low when I turn it on again and it displays 'Bye!'

I've reflashed U4 a few times, no errors, but it doesn't change anything.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 15, 2020, 08:39:21 am
I'm running into a small problem tho:
When it shuts down after the timeout, and when I turn it back on, it's stuck on "Bye!"
I have to remove the battery to turn it on again.
Any idea of where it's coming from? It doesn't happen when I manually turn it off.

Several owners of such clones on the Russian-language forum also drew attention to a similar problem.
There are several options for solving this problem:
1.Remove the U4 chip and replace it with the 2-transistor power control circuit suggested by madires.
2. Replace the U4 chip with a similar one, but with a + 5V power supply (STC15F104W).
3. Remove the DC SL diode from the circuit, which is connected to 2pin U4 from the 78L05 stabilizer
100% solution to this problem is 1st option :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chuck Norris on August 15, 2020, 12:46:11 pm
Thank you Indman & Madires,
now that I know U4 is the problem I will investigate it further.
(3rd solution does't do any good  ;) )
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chuck Norris on August 15, 2020, 01:41:54 pm
Thank you Indman & Madires,
now that I know U4 is the problem I will investigate it further.
(3rd solution does't do any good  ;) )

I thought I'd have fun debugging the thing, but nope.
I just had to recompile the u4.hex. I was using the one in the Objects directory, but the source must have been modified since.
So after recompiling it works flawlessly with the T7.
I've attached the u4.hex if anyone's interested.
Title: Re: $20 LCR ESR Transistor checker project
Post by: cz939 on August 17, 2020, 08:27:09 pm
Congratulations!
Did you measure and note some more characteristic voltages and signals in the "bad" system? Could you share them?
Could you also provide more info on the U4 FW - links, versions and dates? What tools did you use?
[It seems the only source is https://github.com/atar-axis/tc1-u4 - binaries are 1 day/update off!]
Probably presenting of proper settings for T7/TC1 M324PA would be also very helpful for many.
Title: Re: $20 LCR ESR Transistor checker project
Post by: avr on August 18, 2020, 10:12:34 am
Hi

I have a LCR T4 and I have update it to 1.13k firmware version (with the files inside mega328_GM328 folder) and it works well. Now, I want to test the 1.40 M firmware but I can't find how to modify the files to fit my device.

I have used this guide: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926) and I have completed the compilation, but when I uploaded the firmware to the transistor tester the screen was very dark, the letters are reversed but the device measures well the components. So I don' t know how to adapt the 1.40M files to my transistor tester. Could you help me?

Thanks

Title: Re: $20 LCR ESR Transistor checker project
Post by: K595 on August 18, 2020, 10:29:02 am
Добрый день. Хочу обратится к madires. Уменя есть купленный на aliexpress оригинальный Hiland m644 и подключенный дисплей ILI9341, который работает в программном SPI, и я не могу заставить его работать через аппаратный SPI. Прилагаю два фрагмента файла config_644.h, работающий, и не работающий. Я хотел бы чтобы вы объяснили, что я делаю не так. Можно было бы оставить как есть, с программным SPI, но уж очень хочется докопаться до подробностей.

Translated by moderator (using Google Translate)

Good day. I would like to contact madires. I have an original Hiland m644 bought on aliexpress and an ILI9341 display connected that works in software SPI, and I cannot get it to work through hardware SPI. I am attaching two fragments of the config_644.h file, working and not working. I would like you to explain what I am doing wrong. It could be left as is, with software SPI, but I really want to get to the bottom of the details.

Moderator comment: This user has also been notified via PM to keep posts in English for everyones benefit. EEVblog welcomes all, however it's difficult to moderate non-English posts. Let's keep it simple for everyone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: aristarchus on August 18, 2020, 10:36:22 am
Hi

I have a LCR T4 and I have update it to 1.13k firmware version (with the files inside mega328_GM328 folder) and it works well. Now, I want to test the 1.40 M firmware but I can't find how to modify the files to fit my device.

I have used this guide: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926) and I have completed the compilation, but when I uploaded the firmware to the transistor tester the screen was very dark, the letters are reversed but the device measures well the components. So I don' t know how to adapt the 1.40M files to my transistor tester. Could you help me?

Thanks


Read the provided CLONES text document, it is included in ComponentTester-1.40m.tgz

Then, modify the Makefile, config.h and config_328.h with the appropriate parameters from the CLONES document.
I am not sure but it should be the T3/T4 paragraph of settings in CLONES.


These are described in the 1.40m document here
https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/ctester-1.40m.pdf (https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/ctester-1.40m.pdf)
"1.8. Building the firmware", page 9
Title: Re: $20 LCR ESR Transistor checker project
Post by: K595 on August 18, 2020, 11:01:10 am
Thank you, I'll keep it in mind for the future.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 18, 2020, 01:32:14 pm
Good day. I would like to contact madires. I have an original Hiland m644 bought on aliexpress and an ILI9341 display connected that works in software SPI, and I cannot get it to work through hardware SPI. I am attaching two fragments of the config_644.h file, working and not working. I would like you to explain what I am doing wrong. It could be left as is, with software SPI, but I really want to get to the bottom of the details.

The pin assignment for hardware SPI is fine. Since the display is running with bit-bang SPI the wiring is also correct. And the Hiland's rotary encoder in parallel with PB5 and PB7 shouldn't cause any issues. Which firmware version are you using? Are the level shifters fast enough (ILI9341's Vcc is 3.3V)? The clock for hardware SPI is set to f_MCU/2 for the ILI9341.
Title: Re: $20 LCR ESR Transistor checker project
Post by: avr on August 18, 2020, 01:57:25 pm
Hi

I have a LCR T4 and I have update it to 1.13k firmware version (with the files inside mega328_GM328 folder) and it works well. Now, I want to test the 1.40 M firmware but I can't find how to modify the files to fit my device.

I have used this guide: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1011926/#msg1011926) and I have completed the compilation, but when I uploaded the firmware to the transistor tester the screen was very dark, the letters are reversed but the device measures well the components. So I don' t know how to adapt the 1.40M files to my transistor tester. Could you help me?

Thanks


Read the provided CLONES text document, it is included in ComponentTester-1.40m.tgz

Then, modify the Makefile, config.h and config_328.h with the appropriate parameters from the CLONES document.
I am not sure but it should be the T3/T4 paragraph of settings in CLONES.


These are described in the 1.40m document here
https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/ctester-1.40m.pdf (https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/ctester-1.40m.pdf)
"1.8. Building the firmware", page 9

Ok, I coudn't find the file with the instructions. I will read it.

Thanks :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chuck Norris on August 18, 2020, 02:01:25 pm
Congratulations!
Did you measure and note some more characteristic voltages and signals in the "bad" system? Could you share them?
Could you also provide more info on the U4 FW - links, versions and dates? What tools did you use?
[It seems the only source is https://github.com/atar-axis/tc1-u4 - binaries are 1 day/update off!]
Probably presenting of proper settings for T7/TC1 M324PA would be also very helpful for many.

Well, I haven't done much. I've just recompiled the U4 firmware with Keil.
Before updating, with the T7 turned off, I had about 2.8v on PD1 which seemed to power U1 as well (mesured 2V on Vcc pins)
Title: Re: $20 LCR ESR Transistor checker project
Post by: K595 on August 18, 2020, 02:37:38 pm
I am using ComponentTester-1.40m firmware with 16 MHz alum. At the expense of the speed of the level switches, I have 10 kΩ resistors installed. But this phrase "Clock for hardware SPI is set to f_MCU / 2 for ILI9341", I did not understand. I have an 8 channel TXS0108E level converter available. Maybe you should try to install it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 18, 2020, 03:28:45 pm
I am using ComponentTester-1.40m firmware with 16 MHz alum. At the expense of the speed of the level switches, I have 10 kΩ resistors installed. But this phrase "Clock for hardware SPI is set to f_MCU / 2 for ILI9341", I did not understand. I have an 8 channel TXS0108E level converter available. Maybe you should try to install it?

I see, you have in-series resistors to limit current and rely on the internal clamping diodes. Seems to be a timing issue. One solution is to replace the in-series resistors with a proper level shifter, as you already suggested. The other solution is to lower the clock rate of the hardware SPI. That can be done in function LCD_BusSetup() in the section for SPI in ILI9341.c. The line to modify is:
Code: [Select]
  SPI.ClockRate = SPI_CLOCK_2X;

For half the clock rate:
Code: [Select]
  SPI.ClockRate = 0;

And for a quarter:
Code: [Select]
  SPI.ClockRate = SPI_CLOCK_R0 | SPI_CLOCK_2X;

The ILI9341 driver's default clock rate for hardware SPI is f_MCU / 2, i.e. with a 16MHz MCU clock the SPI clock is 8MHz. Half would be 4MHz and quarter 2MHz. And that wouldn't be really faster than bit-bang SPI. IIRC, with an 8MHz MCU clock and bit-bang SPI clearing an ILI9341 based display takes about 3 seconds. So I would go for the level shifter IC to get maximum performance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: K595 on August 18, 2020, 03:54:52 pm
madires, I got it. The situation is starting to clear up. I will experiment with TXS0108E. Thank you for participating.
Title: Re: $20 LCR ESR Transistor checker project
Post by: K595 on August 18, 2020, 07:55:38 pm

madires, I followed your recommendation for TXS0108E and the result is excellent. With the level converter, the hardware SPI is working. It would be nice to note this in the documentation. Many thanks for the help. Another blank spot for me became smaller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ltwin8 on August 19, 2020, 12:03:40 am
Hello, I just came across this thread.

sadly its so long I can not possible read all, I hope that is understandable.

i have two questions:

first: which tester is at the moment the "best"? the M644?
added features:
50V Zener measure
better range resistor

second: I read in the firmwares from https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ComponentTester-1.40m.tgz?view=log (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ComponentTester-1.40m.tgz?view=log) some indications o relays for capacitor discharge, reverse hFe and some other cool nice to haves

is there any new model out here?

can someone point me to instructions, if possible video, on how to flash the new 1.40m firmware from Markus on the m644?

thank you all in advance
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 19, 2020, 10:14:15 am
first: which tester is at the moment the "best"? the M644?

Please see the last 10 pages (it's a common question).

second: I read in the firmwares from https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ComponentTester-1.40m.tgz?view=log (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ComponentTester-1.40m.tgz?view=log) some indications o relays for capacitor discharge, reverse hFe and some other cool nice to haves

is there any new model out here?

can someone point me to instructions, if possible video, on how to flash the new 1.40m firmware from Markus on the m644?

https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation/German (https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation/German)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ltwin8 on August 19, 2020, 11:20:56 am
first: which tester is at the moment the "best"? the M644?

Please see the last 10 pages (it's a common question).

second: I read in the firmwares from https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ComponentTester-1.40m.tgz?view=log (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ComponentTester-1.40m.tgz?view=log) some indications o relays for capacitor discharge, reverse hFe and some other cool nice to haves

is there any new model out here?

can someone point me to instructions, if possible video, on how to flash the new 1.40m firmware from Markus on the m644?

https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation/German (https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation/German)


Hello, thank you, but I did not find understandable instructions for flashing nor found an answer on what's currently the best tester.

is it possible that you just give the answer or direct me to a specific post?

the documentation I found before.

that's why I am asking in here because the instructions are not that understandable to me.

thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 19, 2020, 02:30:28 pm
The README.de and PDF both tell you to simply run "make upload" or to use your IDE. And the last answer to the common "which clone is the best?" question is just 4 pages away: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3127858/#msg3127858 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3127858/#msg3127858). Neither hard to understand nor hard to find. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: ltwin8 on August 19, 2020, 03:19:58 pm
The README.de and PDF both tell you to simply run "make upload" or to use your IDE. And the last answer to the common "which clone is the best?" question is just 4 pages away: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3127858/#msg3127858 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3127858/#msg3127858). Neither hard to understand nor hard to find. ;)

thank you, that two I also found, if that's the common sense now that that are the best all-round testers in this category that's fine, than I guess the stuff with the relays is only found in DIY versions of them.

one more thought is why do they still use the AVR chips and not a STM32 or at least external ADCs like ads1115?

thank you again for your answer. I will try with a real linux installation and not vm. as an IDE I can only think of maybe Arduino or similar?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 19, 2020, 03:58:59 pm
That was also answered in the last 10 pages. ;) You can get free IDEs from Atmel/Microchip for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 20, 2020, 01:42:38 pm
I'm looking for samples of Schottky transistors (AKA Schottky-clamped transistors). The next firmware version will support them and I'm simply connecting a Schottky diode to a BJT for testing. But Schottky-clamped transistors can also have the Schottky diode integrated on the same die which provides some benefits. So I'd like to test those too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2020, 04:36:56 pm
Would you like to know if the hFE of a BJT was measured in the common emitter or common collector circuit?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 31, 2020, 11:33:58 am
madires,Yes, of course :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: jdev99 on August 31, 2020, 05:04:49 pm
For anyone venturing into any of the ready made PCBs from China, I have made case designs suitable for 3D printing for several variants. If you do not have a 3D printer yourself, you can order 3D prints for various places. My designs are:

GM328A: https://www.thingiverse.com/thing:1920077 (https://www.thingiverse.com/thing:1920077)
M12864: http://www.thingiverse.com/thing:1580922 (http://www.thingiverse.com/thing:1580922)
LCR-T4: http://www.thingiverse.com/thing:797733 (http://www.thingiverse.com/thing:797733)
LCR-T3: http://www.thingiverse.com/thing:694790 (http://www.thingiverse.com/thing:694790)
Alphanumeric: http://www.thingiverse.com/thing:641003 (http://www.thingiverse.com/thing:641003)

Thank you egil for your designs.  :-+

I hope you don't mind, I remixed one to be able to use a double 18650 holder with the Hiland M644.
https://www.thingiverse.com/thing:4584702 (https://www.thingiverse.com/thing:4584702)
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on September 02, 2020, 12:12:52 am
Hi guys,

Having some problems with my BSIDE ESR2 Pro running 1.40m

It has started 'freezing'/hanging on the 'Bye!' shutdown screen. The only way to turn the unit off at this point is by removing the battery. Any clues on where to start looking for the fault?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 02, 2020, 09:01:06 am
I'd start with PD6 which switches the power and check the circuit around Q3 and Q2.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 03, 2020, 02:51:07 pm
Hello owners of the popular LCR-T1 clone! For ATMega644 only!
With the help of my friend bdk100@vrtp.ru I managed to adapt k-firmware 1.13k(revision 813) for this device.
It was entertaining in terms of gray matter warm-up.  ;D
The archive, which I attach below, contains a modified configuration file config.h, firmware files in English, and a description file Readme.txt.
Please read it carefully. Happy testing!
Photos were kindly provided by bdk100, who checked and tested this firmware in Russian. :)
There is no support for testing IR RC Detector/Decoder in k-firmware yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 07, 2020, 02:00:43 am
... LCR-T1 clone! For ATMega644 only!

Hello indman, madires and all the other members here in this forum,
my Multi-Funktion-Tester - T7 (the same PCB and all the same Components as LCR-T1) has now I modificated with TC1-Mod, a Rotary-Switch and change the controller to ATmega644PA U-TH.

[attach=1]

The k1.13 firmware and also the m1.40 firmware I flashed successfully and the tester works fine (nearly)!

[attach=2]

1. The k1.13 works fine, but at the top of the display the first 8 rows are wrong pixel?
Have anyone a idea about this wrong pixel???

[attach=3]

2. The m1.40 works also fine, the display looks good - but has a problem with hFE results. Not so great deviations like the "Hiland m644", but clear enough. If I take the workaround for this problem and the hFE results are good.

Best Regards Horst

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 07, 2020, 07:30:37 am
(Attachment Link)
1. The k1.13 works fine, but at the top of the display the first 8 rows are wrong pixel?
Have anyone a idea about this wrong pixel???
Replace the lcd_defines.h file that I attached below and compile again  :)
You can make 8 lines in the main menu if you use the flag in the makefile
CFLAGS + = -DMAX_MENU_LINES = 8
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 07, 2020, 09:41:27 am
Hi indman,

thanks for the prompt reaction at my call for help. :-+ But first, for a old man, needs time for a good breakfast! Later I go to install your hints and report it. In the last night I have detekt an other little bug, but report also later.

Regards Horst 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 07, 2020, 05:07:11 pm
... and report it.
Hi indman,

now the changing are tested - it works, but no 8 wrong lines, now 1. So I set the entry 130 to 131 and no longer wrong lines are in the display!
Many thanks for the right trigger.

The other "little problem": the examples with ATmega644 has all the menu-entrys for Counter with prescaler and xtal messurement for high and lo types as needed vor the example from documentation of Karl-Heinz in the "Figure 2.26. Extended Transistor Tester circuit with ATmega644".

Only the clon "Hiland 644m" comes with this additional hardware <AFAIK>. Is it possible, for testers without this hardware (f.e. TC-1; T7), the unusable menu-entrys deleting?

Best regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 07, 2020, 06:55:11 pm
Only the clon "Hiland 644m" comes with this additional hardware <AFAIK>. Is it possible, for testers without this hardware (f.e. TC-1; T7), the unusable menu-entrys deleting?
Possible! I did this in the firmware I attached above in the archive.
To do this, you need to very very carefully and properly correct the menu items in the function menu.c  file. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 08, 2020, 11:49:51 am
... I did this in the firmware I attached above in the archive.

... sorry, in which archive I can find that modified function menu.c  file?

Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 08, 2020, 01:41:58 pm
Obelix2007,I did not upload the file function menu.c, since each user himself must decide which items to delete and which not. I gave a hint.
Title: Re: $20 LCR ESR Transistor checker project
Post by: upsss on September 11, 2020, 05:35:00 pm
What are the differences between the LCR TC1 and LCR T7 testers, they look the same.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 11, 2020, 08:23:45 pm
@upsss
my Multi-Funktion-Tester - T7 (the same PCB and all the same Components as LCR-T1) has now I modificated with TC1-Mod, a Rotary-Switch and change the controller to ATmega644PA U-TH

... also the same FW I think.

Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 12, 2020, 01:05:24 pm
I've received a report about another Hiland M644 mystery problem, this time regarding the ESR measurement (firmware 1.40m). In the standard probing cycle the ESR values look reasonable but in the ESR check or C monitor the ESR values are way too high. Have you seen that too with your M644?

Edit: Happens for caps >= 470µF.

BTW, the new firmware will support 8 bit parallel bus and disabled extended command set for ILI9341. Some ILI9341 display modules for Arduino come with the extended command set disabled for whatever reason. And the SH1106 OLED controller will be supported too. Several OLED modules sold as SSD1306 actually have an SH1106. Both controllers are quite similar but not identical. The SH1106 can drive four additional columns, for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 12, 2020, 05:14:14 pm
... Have you seen that too with your M644?

... no, my "Hiland M644", my "M644-Lochraster" and my new "mod. T7 M644" has nearly the same ESR values at all three operating modes with the same DUT.

But the values at smaller capacitors (not only with M644 testers, also with the M328th in M1.40 FW) are to high in comparison to K1.13 FW testers  and my Gen_Rad_1687_LCR_Digibridge.

Horst

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 12, 2020, 05:28:06 pm
Obelix2007, can you check on your M644 devices ESR measurement at 1000μF capacitor in C-monitor mode and compare them with measurement in standart mode?
m-firmware 1.40.
Title: Re: $20 LCR ESR Transistor checker project
Post by: K595 on September 12, 2020, 06:33:51 pm
indman, Maybe my measurements will fit. Two measurements were made in each mode. Firmware 1.40.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 12, 2020, 06:48:51 pm
K595, thanks, this confirms the problem. Now there is another mystery for the madires. I think he will solve it successfully, as usual.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 12, 2020, 09:21:45 pm
Obelix2007, can you check on your M644 devices ESR measurement at 1000μF capacitor in C-monitor mode and compare them with measurement in standart mode?
m-firmware 1.40.

... the tests I have done, only my Selfmade with a M644 40p DIP hasn't this problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 13, 2020, 03:44:11 am
Hello K595,

... you have a "Hiland M644" with M1.40 firmware,  so I want to ask you:

Please can you test for me a PNP transistor BC558C or similar and tell me the hFE value? A year ago I have found a problem with hFE values 1500 and more with such components, at other testers with 328s the value a "normal" between 400 and max. 600 hFE.
[attachimg=1]

Best regards

Horst

Title: Re: $20 LCR ESR Transistor checker project
Post by: K595 on September 13, 2020, 06:46:11 am
Hi Obelix2007, I tested two BC558C transistors as you requested. Results in the photo. Sorry for the quality of the photo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 13, 2020, 08:39:13 am
... the tests I have done, only my Selfmade with a M644 40p DIP hasn't this problem.
Your Selfmade with a M644 tester also measures ESR incorrectly. I see ESR 0.20 in the photo, which exceeds the real 0.04-0.07 one by 4-5 times.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 13, 2020, 10:28:59 am
@ indman

... may be the absolut values of ESR are incorrect, but the question in this time was the deviation bitween the two methods "normal" component test and test in the continous test "C Monitor".
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 13, 2020, 10:43:28 am
Hi Obelix2007, I tested two BC558C transistors as you requested. Results in the photo. Sorry for the quality of the photo.

... thank you for the test.

In the hardware-configuration of your "Hiland" did you activatet the workaround #define NO_HFE_C_RL?

In this case has my "Hiland" tester the "normal" values too.

Best regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: K595 on September 13, 2020, 11:13:39 am
Obelix2007, Yes, you are right. I have commented out the #define NO_HFE_C_RL line. Strange indications. But I cannot explain it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 13, 2020, 11:35:41 am
... cannot explain it.

... oh, that was fast, thank you!

... comment of Markus: *    Hiland M664 (under investigation)  8)

Greetings Horst

P.S.  your new display for the "Hiland" looks better then the "Orginal"!!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 13, 2020, 03:46:35 pm
The Hiland ESR issue is intriguing. It also happens in the normal probing cycle when the cap is connected to probes #1 and #2, which is the last check performed. A quick & dirty workaround is to add a MeasureCap() for another pin pair before measuring the ESR. More to come ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 13, 2020, 06:21:59 pm
Looks like I found a way to solve the Hiland ESR issue. Please edit both functions MeasureESR() in cap.c. Yep, there are two. Look for

Code: [Select]
  /*
   *  init stuff
   */

  DischargeProbes();                    /* try to discharge probes */
  if (Check.Found == COMP_ERROR) return ESR;   /* skip on error */

and insert below

Code: [Select]
  /*
   *  init stuff
   */

  DischargeProbes();                    /* try to discharge probes */
  if (Check.Found == COMP_ERROR) return ESR;   /* skip on error */

  DischargeProbes();
  DischargeProbes();

Yes, it's weird.
Title: Re: $20 LCR ESR Transistor checker project
Post by: K595 on September 13, 2020, 07:43:14 pm
Madires, After editing the cap.c file, everything began to show normally. Thank.
Title: Re: $20 LCR ESR Transistor checker project
Post by: FearTec on September 13, 2020, 11:23:54 pm
Where is the best place to order the latest venison of the M328 tester?

Featured here
https://www.youtube.com/watch?v=7Br3L1B80ow (https://www.youtube.com/watch?v=7Br3L1B80ow)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 14, 2020, 01:53:32 am
... Hiland ESR issue.

... hallo madires,

May be, it is not only a problem with the Hiland and his M644, my testers T7, TC-1, T3 and T4 have the same ESR issue. Only the testers with a DIL (28/40) package are without this problem!

Best regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 14, 2020, 09:25:30 am
I don't think it's a DIL vs. non-DIL issue. A tester with a QFN ATmega328 (Nick's PCB) shows consistent ESR values without the patch.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 14, 2020, 09:28:09 am
Where is the best place to order the latest venison of the M328 tester?

Wherever you like. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 14, 2020, 04:53:43 pm
Looks like I found a way to solve the Hiland ESR issue. Please edit both functions MeasureESR() in cap.c.

Not really. It only mitigates the problem for caps up to about 2200µF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on September 15, 2020, 12:35:58 am

The problem I have with the cheap $20 checkers is REPEATABILITY and RELIABILITY of results.
For example, an electro cap may read a certain value (or esr) on first check .... remove it ... short it to discharge ... repeat the check ... and wham ... readings are anywhere from either slightly different to very different.

How do I "upgrade" the same $20 checker for better (more RELIABLE and REPEATABLE) performance?

I have not tried out any of the pricer (name brand) meters, like BK or Fluke.

I do own two Fluke DMMs including the 87. And, frankly, in my experience, the 87 is also not all that RELIABLE and REPEATABLE, sometimes requiring a power cycle to clear its memory or software lockup.

I haven't gone thru this thread (much less all of EEVblog) for some solution to my queries below, so please throw some links as necessary.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Peeps on September 15, 2020, 02:09:01 am
I'm running the MK-328 tester (atmega328p) and just upgraded to the 1.40m firmware. It seems to be working fine for most things, except it won't properly detect these TRIACS I have. They're model BTA16-800BW (datasheet (https://www.digchip.com/datasheets/download_datasheet.php?id=197717&part-number=BTB16-800BW)), and it shows them as being a ~60ohm resistor between the Gate and M1 regardless of how the leads are connected.

The TRIACS are definitely good as they're brand new from digikey, and read the same as the old ones I was going to replace them with.

Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on September 15, 2020, 02:37:28 am
What are important differences between MK-328 and LCR-TC1 testers?
They are similar price on ebay or Ali.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 15, 2020, 10:14:11 am
I'm running the MK-328 tester (atmega328p) and just upgraded to the 1.40m firmware. It seems to be working fine for most things, except it won't properly detect these TRIACS I have. They're model BTA16-800BW (datasheet (https://www.digchip.com/datasheets/download_datasheet.php?id=197717&part-number=BTB16-800BW)), and it shows them as being a ~60ohm resistor between the Gate and M1 regardless of how the leads are connected.

Please see the README, section Displaying Results / Additional Hints / TRIACs. That TRIAC needs more current than the tester is able to provide.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 15, 2020, 10:22:29 am
What are important differences between MK-328 and LCR-TC1 testers?
They are similar price on ebay or Ali.

The TC-1 has a color display, IR receiver module and boost converter for the Zener check (up to about 35V). And it comes with an ATmega324 or 644 plus an annoying control MCU (requires reprogramming or replacement with a simple two-transistor circuit).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 15, 2020, 11:14:47 am
The problem I have with the cheap $20 checkers is REPEATABILITY and RELIABILITY of results.
For example, an electro cap may read a certain value (or esr) on first check .... remove it ... short it to discharge ... repeat the check ... and wham ... readings are anywhere from either slightly different to very different.

It should be clear that the Transistortester isn't a precision instrument, but it can be quite accurate. Most problems are caused by a cheap power supply circuitry.

BTW, you don't need to remove the cap for discharging between probing cycles. Just keep it inserted. But make sure it's discharged before inserting.

How do I "upgrade" the same $20 checker for better (more RELIABLE and REPEATABLE) performance?

MCP1702/MCP1703 and remove the TL431. Don't forget to run the self-adjustment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on September 15, 2020, 02:37:10 pm
The problem I have with the cheap $20 checkers is REPEATABILITY and RELIABILITY of results.
For example, an electro cap may read a certain value (or esr) on first check .... remove it ... short it to discharge ... repeat the check ... and wham ... readings are anywhere from either slightly different to very different.

It should be clear that the Transistortester isn't a precision instrument, but it can be quite accurate. Most problems are caused by a cheap power supply circuitry.

BTW, you don't need to remove the cap for discharging between probing cycles. Just keep it inserted. But make sure it's discharged before inserting.

How do I "upgrade" the same $20 checker for better (more RELIABLE and REPEATABLE) performance?

MCP1702/MCP1703 and remove the TL431. Don't forget to run the self-adjustment.
You mean replace the TL431 with MCP1702/03?
About the PSU ... I assume 9v (which is the default for my tester, via the battery jack) is okay??? If not, please make specific suggestions. For example, a 9v ac/dc wall-wart adapter --- but with extra filtration and/or better regulation.

Let's say that our goal is create a $30 meter that can match, say, the BK 879B --- Is this possible?

(https://bkpmedia.s3.amazonaws.com/photos/87xB_front_lrg.jpg)

https://www.bkprecision.com/products/component-testers/879B-40000-count-dual-display-handheld-lcr-meter-with-esr.html (https://www.bkprecision.com/products/component-testers/879B-40000-count-dual-display-handheld-lcr-meter-with-esr.html)

Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on September 15, 2020, 04:06:58 pm
I just checked what I have .... it's an "MTester" ...

(https://www.elektor.com/media/catalog/product/cache/5562f759999b940b867d7ecf207c58b6/6/1/61mz_loh9_l._sl1000_.jpg)

The regulator is 78L05. Not sure how to improve on this topology????

(https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/?action=dlattach;attach=202318;image)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 15, 2020, 04:22:54 pm
You mean replace the TL431 with MCP1702/03?

Nope, replace the 5V regulator with an MCP1702/03 and remove the TL431.

About the PSU ... I assume 9v (which is the default for my tester, via the battery jack) is okay??? If not, please make specific suggestions. For example, a 9v ac/dc wall-wart adapter --- but with extra filtration and/or better regulation.

9V battery is fine.

Let's say that our goal is create a $30 meter that can match, say, the BK 879B --- Is this possible?

No, the Transistortester isn't an LCR meter which typically uses an AC test signal. Completely different measurement method.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 15, 2020, 04:24:22 pm
I just checked what I have .... it's an "MTester" ...

... or commonly known as T4 clone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 15, 2020, 04:44:54 pm
Not really. It only mitigates the problem for caps up to about 2200µF.

Update:
For some unknown reason the residual voltage of a large value cap is higher on the Hiland M644 and some other clones. The algorithm of the ESR measurement is able to compensate some residual voltage, e.g. caused by dielectric absorption, but in this case the voltage is too high. Despite the cap being discharged before the ESR measurement the residual voltage stays quite high. I've added a dedicated function to discharge caps which works fine so far (tested up to 10mF).
Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on September 15, 2020, 08:51:01 pm
No, the Transistortester isn't an LCR meter which typically uses an AC test signal. Completely different measurement method.
Are you sure? I'm referring to tester shown in my photos (MTester). It can test L, C, R, ESR, as well as semiconductors (trans, diodes). It does test using high-freq AC sweep.
Title: Re: $20 LCR ESR Transistor checker project
Post by: edavid on September 15, 2020, 09:14:27 pm
No, the Transistortester isn't an LCR meter which typically uses an AC test signal. Completely different measurement method.
Are you sure?
:palm:

Quote
I'm referring to tester shown in my photos (MTester). It can test L, C, R, ESR, as well as semiconductors (trans, diodes).
That doesn't make it an LCR meter.

Quote
It does test using high-freq AC sweep.
No, it doesn't.  Consult the source code and documentation.

However... I think it's clearer to say that an LCR meter like the B+K 879B uses a vector (phase sensitive) measurement technique.  The Transistortester only makes scalar measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on September 15, 2020, 10:01:44 pm
That doesn't make it an LCR meter.
Your comments are CONFUSING .... to say the least!!
Please note the title of this thread. See the "LCR" ? ;)
I would buy it if you said that the BK unit is a better, more reliable implementation of supporting metrology. But note the original goal of the $20 LCR ESR Transistor checker project was to bring formally expensive-to-do measurements (e.g. BK or Peak tools, and all their functionality ) down to a bare-bones price.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CatalinaWOW on September 16, 2020, 02:23:39 am
That doesn't make it an LCR meter.
Your comments are CONFUSING .... to say the least!!
Please note the title of this thread. See the "LCR" ? ;)
I would buy it if you said that the BK unit is a better, more reliable implementation of supporting metrology. But note the original goal of the $20 LCR ESR Transistor checker project was to bring formally expensive-to-do measurements (e.g. BK or Peak tools, and all their functionality ) down to a bare-bones price.

We are now dancing around the definition of functionality.  The $20 meter measures L, C and R so by some definition it is an LCR meter.  And the accuracy it achieves is more than sufficient for a great many purposes.  If it is not sufficient for your purposes you are doing something which requires more than basic knowledge, and you should know what you need and in what ways this meter doesn't do it.  You should also know if the fancier LCR meters that cost hundreds or thousands of dollars are adequate to your purpose.  There are times when they are not.

A 2.5 digit DMM and a 8 digit DMM are both DMMs.  The 2.5 digit unit is actually adequate for what I would guess is the high nineties percent of all readings.  But it won't do what the 8 digit unit will do, and should never be confused with it.  If you look at the single specification of price there should be little chance of confusion.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 16, 2020, 05:45:02 am
Your comments are CONFUSING .... to say the least!!

This absolutely does not bother those people who constantly follow this topic and have carefully studied all the documentation, kindly and gratuitously provided by the authors of the project. Many thanks to them for this great work!  :-+
First of all, this project is Transistor checker project ! LCR measurement is bonus functions that the authors were able to implement based on the capabilities and limitations of the simplified circuitry of this device. They do not claim metrological accuracy! You should always remember this and do not try to put specialized professional LCR meters and this project on the same scales.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on September 16, 2020, 02:40:28 pm
Your comments are CONFUSING .... to say the least!!
This absolutely does not bother those people who constantly follow this topic and have carefully studied all the documentation, kindly and gratuitously provided by the authors of the project. Many thanks to them for this great work!  :-+
[   :blah:   ]

First of all, this project is Transistor checker project ! LCR measurement is bonus functions that the authors were able to implement based on the capabilities and limitations of the simplified circuitry of this device. They do not claim metrological accuracy! You should always remember this and do not try to put specialized professional LCR meters and this project on the same scales.
But I am putting " this project on the same scales." And, thus, your reply is a complete FAIL!!!  |O :-DD

We are now dancing around the definition of functionality.  The $20 meter measures L, C and R so by some definition it is an LCR meter. 
Oh, so now (despite the thread title) it's "by some definition it is an LCR meter.  " :bullshit:  |O |O :-DD :-DD. Y'all just stick up fer one another, mincing words,  without rhyme or reason. Geeeeeeeeeeeeeeeeeeeeeeeeezusssssssssssssss!

Okay, so now let a low-post-count "Regular Contributor" like me throw some advice.
You might want to reply back with some rhyme or reason. For example, BKP created a product video detailing how LCR meter works for various components.

https://youtu.be/zZiVvgUiRdc (https://youtu.be/zZiVvgUiRdc)

(Watch this short video, and pay attention class!!!! This is how to reply. HINT: Y'all might wanna say, e.g., how the MTester selects and spits out test signals to "sweep" for component type, etc.). Now some/all this info may already be in this thread. In my orig. query post, which OBVIOUSLY most y'all didn't read,  I specifically asked for links. But y'all apparently neglected that in favor of throwing out spitfire, diatribes and criticism. GEEEEEEEEEEEEEEEEEEEEEZUSS  :-//  :palm:

Well here's lookin' back at ya kids ..... and a one more thanggggggggggggggggggggggg...
https://www.youtube.com/watch?v=IDDEpnjgTyw (https://www.youtube.com/watch?v=IDDEpnjgTyw)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 16, 2020, 03:31:07 pm
Please read https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/ttester-1.13k.pdf!

I don't expect anyone to read this whole thread, but the common questions about which tester to buy, how to pimp your tester or where to find the documentation are answered usually in the last ten pages. There's also a nice text field at the top right for searching this topic. ;)

So please let's keep this discussion civilized!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 16, 2020, 03:56:19 pm
No, the Transistortester isn't an LCR meter which typically uses an AC test signal. Completely different measurement method.
Are you sure? I'm referring to tester shown in my photos (MTester). It can test L, C, R, ESR, as well as semiconductors (trans, diodes).

And with a current firmware it will do many things more. But as one of the two developers of this OSHW project I'm pretty sure. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 16, 2020, 05:13:10 pm
But I am putting " this project on the same scales." And, thus, your reply is a complete FAIL!!!  |O :-DD
Are you sure? I'm referring to tester shown in my photos (MTester). It can test L, C, R, ESR, as well as semiconductors (trans, diodes).
This manner of communication reminds me very much of one "gentleman" Stan21, doesn't it? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on September 17, 2020, 03:26:07 am
This manner of communication reminds me very much of one "gentleman" Stan21, doesn't it? :)
Exactly what I was thinking. I marvel at how skilled some people are at making complete jack-asses of themselves. It requires a stupendous lack of self reflection.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on September 17, 2020, 02:46:30 pm
This manner of communication reminds me very much of one "gentleman" Stan21, doesn't it? :)
Exactly what I was thinking. I marvel at how skilled some people are at making complete jack-asses of themselves. It requires a stupendous lack of self reflection.
The WHACKY responses to y'alls lazy AF replies are exactly what you DESERVE. I openly admitted I don't know exactly how the MTester works. And asked some legitimate questions....e.g., a brief overview of how the MTester works (compared to a formal LCR meter, like BK)
 But what I got instead was the typical dismissals or smarty-pants lazy AF responses -- all typical of sciency forums.
KEEP IN MIND A COUPLE O' 'PORTANT FACTS-O-LIFE:
Y'all have spent over 260 pages on a friggin' $7 tester  :-DD
Some of you claimed the MTester is NOT an LCR meter (despite the title of this thread, one of you actually said this )   |O  :-DD

So ... I'm still waiting for a few words -- or a hyperlink -- on how the "$20 LCR ESR Transistor checker" works. That's not that big of an ask, exp. given the size and messiness of this thread.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Simon on September 17, 2020, 03:19:22 pm
This manner of communication reminds me very much of one "gentleman" Stan21, doesn't it? :)
Exactly what I was thinking. I marvel at how skilled some people are at making complete jack-asses of themselves. It requires a stupendous lack of self reflection.
The WHACKY responses to y'alls lazy AF replies are exactly what you DESERVE. I openly admitted I don't know exactly how the MTester works. And asked some legitimate questions....e.g., a brief overview of how the MTester works (compared to a formal LCR meter, like BK)
 But what I got instead was the typical dismissals or smarty-pants lazy AF responses -- all typical of sciency forums.
KEEP IN MIND A COUPLE O' 'PORTANT FACTS-O-LIFE:
Y'all have spent over 260 pages on a friggin' $7 tester  :-DD
Some of you claimed the MTester is NOT an LCR meter (despite the title of this thread, one of you actually said this )   |O  :-DD

So ... I'm still waiting for a few words -- or a hyperlink -- on how the "$20 LCR ESR Transistor checker" works. That's not that big of an ask, exp. given the size and messiness of this thread.



Have you finished or do you need finishing? I don't care what others have said your posts are rather over the top and if anything anyone said warranted such rubbish then you report it rather than posting that crap!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 17, 2020, 04:27:55 pm
So ... I'm still waiting for a few words -- or a hyperlink -- on how the "$20 LCR ESR Transistor checker" works. That's not that big of an ask, exp. given the size and messiness of this thread.

Apparently you've missed the linked documentation a few posts earlier. That PDF explains all the details. It helps if you can read. >:D
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on September 17, 2020, 07:51:27 pm
... if you can read. >:D
Judging from his command of English, not very well
Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on September 18, 2020, 05:15:37 pm
Apparently you've missed the linked documentation a few posts earlier. That PDF explains all the details. It helps if you can read. >:D
Literally a legitimate case for expression: TL;DR  |O |O

You project insiders should be able to dumb down the workings to a lay audience. It really will help you better assess WTF you've been investing your time/effort in for 260+ pages ..... a $7.00 tester that was originally obtained from China (i.e., someone had already done the hard work and math ).  ;D  LOL!!!  :-DD

The CHALLENGE is to summarize  how the MTester works, for non-project-insiders .... in, say, 100 words.
Say, I put any component on the ZIF and push "Test" .... how does the MTester first scan the ZIF ... and, after the "first scan", what comes next?
Or do I need to visit China EE forums for the answers?  :-DD

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 18, 2020, 07:26:32 pm
Sorry, we don't have any version which doesn't exceed Twitter's limit of 280 characters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: CatalinaWOW on September 19, 2020, 01:45:29 am
But if you read the long version you will find the math, in German (where this originated) and translated to English.  The Chinese who copied and commercialized this have never to my knowledge provided any decent documentation.

I also don't understand your obsession with mid-range LCR meters that essential measure the three elements of a single component over a small frequency range.  If your really wanted to be snobbish about it you would want a VNA.  But then you could look into the microVNA which does much of what an instrument that cost more than a luxury car for about $100. 

The microVNA also benefits from som RTFM where you will find that it originated in Texas and has then been copied, commercialized  and improved by the Chinese.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on September 19, 2020, 03:51:30 am

You project insiders should be able to dumb down the workings

No way. You are doing an amazing job of dumbing things here. Please carry on.


you've been investing your time/effort in for 260+ pages
Thank you for YOUR investment. You have almost set a new bar against which we will compare future spazzes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 20, 2020, 12:41:22 am
I gave a hint.

Hi indman,

thank you for your support and your hint's.

Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 20, 2020, 08:10:56 am
The CHALLENGE is to summarize  how the MTester works, for non-project-insiders .... in, say, 100 words.
Obelix2007, now that you have successfully trained your gray matter using this small piece of code as an example, you understand what a tremendous work the authors of the project have done in order for people Stan21 and 13hm13 were able to get their favorite MTester !!! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: 13hm13 on September 21, 2020, 03:11:30 am
NOTE: This message has been deleted by the forum moderator Simon for being against the forum rules and/or at the discretion of the moderator as being in the best interests of the forum community and the nature of the thread.
If you believe this to be in error, please contact the moderator involved.
An optional additional explanation is:
Title: Re: $20 LCR ESR Transistor checker project
Post by: pierreraymondrondelle on September 21, 2020, 08:28:38 am
 
Quote
... and that info reveals nothing about how the MTester works.
« Last Edit: Today at 03:13:12 am by 13hm13 »

Please, don't expect one will do YOUR job for you. Do it yourself: Read the manual and stop trolling

Please, moderator, may you ban this guy ?
Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on September 21, 2020, 05:03:25 pm
:-DD
Obelix2007, now that you have successfully trained your gray matter using this small piece of code as an example, you understand what a tremendous work the authors of the project have done in order for people Stan21 and 13hm13 were able to get their favorite MTester !!! :)
First, the language in Obelix2007 post  ist nicht Englisch ... it is Schweinhund !!!
But one can always Google Translate ... and that info reveals nothing about how the MTester works.

Better ask for your money back
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 25, 2020, 04:32:26 pm
This time we have a lot of improvements, new features and a driver for SH1106 based OLED displays:

v1.41m
- New remote command "MHINT" for hints about measurements (at the moment just the test circuit type for h_FE).
- Added auto mode (automatic update) to DS18B20 tool (suggested by  Obelix2007@EEVblog).
- Added additional discharge function to resolve ESR issue on some tester clones (reported by indman@EEVblog). ESR value was way too high for cap >= 470µF connected to probes #1 and #2, in ESR tool, C monitor and RCL monitor. And for cap >= 4700µF in all modes. Affected testers are Hiland M644 and TC-1 variants.
- Updated degree character in font_16x26_hf.h and font_16x26_iso8859-2_hf.h (changes provided by Bohu).
- Driver for OLED controller SH1106 (3-wire SPI, 4-wire SPI and I2C; thanks to Old-Papa for providing a sample display).
- Fixed issue with missing setup of optional /RES line for I2C in SSD1306 driver.
- Added output of test circuit type for hFE.
- Changed output of hexadecimal values to lowercase by default and added switch to enable uppercase (UI_HEX_UPPERCASE).
- Option for OneWire related tools to also read and display the ROM code (ONEWIRE_READ_ROM, suggested by indman@EEVblog).
- Swapped DQ and Vcc probes for OneWire bus to match sensor pinout (suggested by indman@EEVblog).
- Added detection for Schottky-clamped BJTs (SW_SCHOTTKY_BJT).
- Improved detection of depletion mode FETs by adding filter for Schottky-clamped BJTs.
- Optimized text line management for clearing the display.
- Added special display driver for identifying display controllers.
- Added R/C/L monitor (SW_MONITOR_RCL, suggested by indman@EEVblog).
- Fixed problem with jumping inductance values in L and R/L monitor (reported by indman@EEVblog).
- Added measurement of V_GS(off) for depletion-mode FETs (suggested by joshto@EEVblog). Also added "V_GS_off" command to remote command option.
- Added support for 8-bit parallel bus to ILI9341 driver. Also added a configuration switch for ILI9341 with diabled extended command set (LCD_EXT_CMD_OFF, thanks to Bohu for providing a sample display).
- Added 16x26 cyrillic font (FONT_16X26_WIN1251_HF, provided by Yuriy_K@VRTP.RU).
- Fixed missing µ (micro) in multiple ISO8859-2 fonts (reported by indman@EEVblog and Obelix2007@EEVblog).
- Fixed transposed digits for ATmega 2560 in Makefile (reported by Bohu).
- Colored battery status for color displays (suggested by indman@EEVblog).
- Replaced alternative 8x16 win1251 font with an updated version provided by indman@EEVblog.
- Fixed issue with validity check of low value resistors in CheckResistor() (reported by indman@EEVblog).
- Updated SmallResistor(), MeasureInductance() and GetGateThreshold() to support ADC_LARGE_BUFFER_CAP.
- Added missing update of ADC reference source to MeasureInductance() and GetGateThreshold().
- Added option to select the adjustment profile after powering on (UI_CHOOSE_PROFILE, suggested by Bohu).
- Added dedicated monitoring tools for resistors and inductors (SW_MONITOR_R, SW_MONITOR_L, suggested by indman@EEVblog).
- Updated Spanish texts (thanks to pepe10000@EEVblog).

Download 1.41m at https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on September 26, 2020, 09:16:58 am
For madires.

New Spanish translation file with the latest additions.

Thanks and best regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 26, 2020, 02:02:33 pm
A quick fix for 1.40m and 1.41m when enabling SW_R_E96_T or SW_R_E96_CC. Edit config.h and search for:
Code: [Select]
  #define SW_E86

Change that into:
Code: [Select]
  #define SW_E96

Thanks to Obelix2007 for pointing this out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jacon on September 27, 2020, 07:08:21 am
For Markus

Polish ISO translation file for v1.41 enclosed.
Win file is OK as it is  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 03, 2020, 12:08:19 pm
Hello everybody!
I offer all owners of the AY-AT clone as well as the GM328A black board clone a slightly modified version of the m-firmware 1.41m in English! I showed the functions that fit into the firmware in the photo.
You can download and check this firmware for 3 different processor frequencies - 8,16 and 20Mhz.
I excluded the "ESR" item from the main menu, since I do not use measurements in the circuit using this device. For this purpose, I have other devices.
But ESR measurement works fine in other modes when measuring C and monitors. ;) Madires has not yet provided such an option in config.h, so I edited the code a bit.
I also want to share the option of replacing a large quartz resonator with a small-sized ceramic SMD Murata 16MHz crystal. In the photo, I showed with blue arrows those parts that I removed from the front side of the board and the back side, on which the new die is installed. This crystal already has a 15pF capacitance to ground inside the case, which is necessary for the start. Therefore, two 22pF capacitors can be removed from the front side of the board.
I am also attaching an updated instruction in Russian in pdf format for the madires github collection! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on October 03, 2020, 06:29:41 pm
what is the advantage of the crystal? Do you get more accurate results?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 03, 2020, 07:29:40 pm
what is the advantage of the crystal? Do you get more accurate results?
No, I did not notice any significant difference in the stability and accuracy of the readings between the ceramic and quartz crystal.
The main advantages of a ceramic crystal are small dimensions, there is no need for precise adjustment after installation, and also fewer parts on the board.
But the frequency at which the crystal operates has a noticeable effect on the measurement results.
Previously, my AY-AT had a 20MHz crystal. I noticed that the tester was unstable at this frequency.
Most of the Chinese-made ATMega328 processors are very unstable at 20MHz. This is especially noticeable when measuring the ESR of capacitors.
At 16MHz, these same processors work much more stable and predictable.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on October 05, 2020, 06:33:43 am

I excluded the "ESR" item from the main menu, since I do not use measurements in the circuit using this device. For this purpose, I have other devices.
But ESR measurement works fine in other modes when measuring C and monitors. ;) Madires has not yet provided such an option in config.h, so I edited the code a bit.


Hi indman.

I find it very interesting since I do not use that menu option either and it could save some memory by keeping the ESR measurement in other modes.

I wonder if it would be possible for you to share the edited code or the modified file while madires considers adding that option to config.h for some testing.

Thanks and best regards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 05, 2020, 08:48:58 am
Ok, I'll put that on the to-do list.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tongbajiel on October 05, 2020, 03:33:07 pm
Hello everybody!
I offer all owners of the AY-AT clone as well as the GM328A black board clone a slightly modified version of the m-firmware 1.41m in English! I showed the functions that fit into the firmware in the photo.
You can download and check this firmware for 3 different processor frequencies - 8,16 and 20Mhz.
I excluded the "ESR" item from the main menu, since I do not use measurements in the circuit using this device. For this purpose, I have other devices.
But ESR measurement works fine in other modes when measuring C and monitors. ;) Madires has not yet provided such an option in config.h, so I edited the code a bit.
I also want to share the option of replacing a large quartz resonator with a small-sized ceramic SMD Murata 16MHz crystal. In the photo, I showed with blue arrows those parts that I removed from the front side of the board and the back side, on which the new die is installed. This crystal already has a 15pF capacitance to ground inside the case, which is necessary for the start. Therefore, two 22pF capacitors can be removed from the front side of the board.
I am also attaching an updated instruction in Russian in pdf format for the madires github collection! :)
Hello indman, Can you give the source code for Markus firmware, which can be simulated in proteus with ST7735 lcd. I've tried it myself, but still can't show anything until now. thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 05, 2020, 04:44:43 pm
tongbajiel,sorry no, i already answered before https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1578637/#msg1578637 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1578637/#msg1578637)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on October 08, 2020, 05:02:48 am
Hi, I have problem when measure cap 70mF, tester still detect it as battery, maybe 2/50 times detect 72mF but next time measurement was wrong. 35mF is correctly measure. I have Hiland M644 without any mod hardware and latest fw 1.41m with default settings like timings, voltages etc. I dont know if this problem is on previous ver fw Markus but on fw Karl-Heinz measurement is correctly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on October 08, 2020, 07:57:23 am
...and latest fw 1.41m with default settings...

...

/*
 *  Maximum voltage at which we consider a capacitor being
 *  discharged (in mV).
 */

#define CAP_DISCHARGED   2

change this entry to

#define CAP_DISCHARGED   4

maybe 5 or 6.

The compared value in K software is standard of 4

# The CAP_EMPTY_LEVEL  defines the empty voltage level for capacitors in mV.
# Choose a higher value, if your Tester reports "Cell!" by unloading capacitors.
CFLAGS += -DCAP_EMPTY_LEVEL=4


Horst

Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on October 08, 2020, 07:59:01 am
Ok, I check this in the evening, thank You.

So, change value in #define CAP_DISCHARGED from 2 to 8 solve problem. A propos, maximum measure capacity is 105mF.
Thanks Obelix2007  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 08, 2020, 04:38:22 pm
Since madires has published the new version 1.41m, I have updated the comparison tables for the most popular clones. ;) In tables there is also a small addition to the information on supply voltage monitoring.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on October 09, 2020, 05:09:50 am
I have next question. I can't measure quartz resonator over 15MHz in HF mode because have result 340kHz, 850kHz etc. I try 16. 20, 24MHz new and used. In LF mode have same but maybe my component was wrong, try today with different. Any sugestion?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 09, 2020, 10:09:44 am
Do you have a Hiland M644 or a DYI version with the extended frequency counter? Have you checked the oscillator frequency of the extended frequency counter with a scope?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 09, 2020, 11:15:46 am
Hello everybody!  I'm new to the forum, but old in electronics! ;)

I have a request for indman: please tell me with what software you compiled the 1.41m version. I have an M328 AY-AT on which I want to put the 1.41m software customized (special thanks madires!). I tried make in Debian and cygwin / Win7-64; I have compilation errors in both variants. I get error messages that some variables are not declared.

Thank you.§
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 09, 2020, 11:49:17 am
Dumidan
for Windows optimal https://drive.google.com/file/d/1DL5--2RUFIncdO8PmW87Bz9DzwPw5ms0/view?usp=sharing (https://drive.google.com/file/d/1DL5--2RUFIncdO8PmW87Bz9DzwPw5ms0/view?usp=sharing)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 09, 2020, 01:27:10 pm
indman thanks for the quick reply, but ...

I downloaded the tools package, I installed it according to README. I ran pn and got the same error message!

> "make.exe" all
avr-gcc -mmcu=atmega328 -Wall -I. -Ibitmaps -DF_CPU=8000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -mcall-prologues -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT main.o -MF dep/main.o.d -c main.c
main.c: In function 'Show_Fail':
main.c:360: error: 'Failed1_str' undeclared (first use in this function)
main.c:360: error: (Each undeclared identifier is reported only once
main.c:360: error: for each function it appears in.)
main.c:361: error: 'Failed2_str' undeclared (first use in this function)
main.c: In function 'Show_Error':
main.c:376: error: 'DischargeFailed_str' undeclared (first use in this function)
main.c: In function 'Show_BJT':
main.c:1095: error: 'BJT_str' undeclared (first use in this function)
main.c: In function 'Show_ThyristorTriac':
main.c:1567: error: 'Thyristor_str' undeclared (first use in this function)
main.c:1573: error: 'Triac_str' undeclared (first use in this function)
main.c: In function 'Show_PUT':
main.c:1608: error: 'PUT_str' undeclared (first use in this function)
main.c: In function 'Show_UJT':
main.c:1643: error: 'UJT_str' undeclared (first use in this function)
main.c: In function 'PowerOff':
main.c:1728: error: 'Bye_str' undeclared (first use in this function)
main.c: In function 'ShowBattery':
main.c:1758: error: 'Battery_str' undeclared (first use in this function)
main.c:1788: error: 'Low_str' undeclared (first use in this function)
main.c:1795: error: 'Weak_str' undeclared (first use in this function)
main.c:1802: error: 'OK_str' undeclared (first use in this function)
main.c: In function 'main':
main.c:1985: error: 'Timeout_str' undeclared (first use in this function)
main.c:1986: error: 'Error_str' undeclared (first use in this function)
main.c:2103: error: 'Tester_str' undeclared (first use in this function)
main.c:2263: error: 'Probing_str' undeclared (first use in this function)
make.exe: *** [main.o] Error 1

> Process Exit Code: 2
> Time Taken: 00:03

Where is the mistake? How do I solve the problem?
Please explain to me in more detail, I am a beginner in programming.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 09, 2020, 01:55:28 pm
Dumidan,publish your madires 1.41m source folder where you are compiling?
You can zip  file archive
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on October 09, 2020, 05:15:52 pm
I have Hiland M644 with 8MHz resonator. No, no i didn't check and now it's impossible. My conclusions: when run freq counter and try measure BNC, HF and LF I have in dedicated places is still "0" value. I have DMM with L measure so connect probes to BNC Tester because this is generator 1,394kHz and voilà - DMM "unlock" tester and now I can take a measurement so BNC work, LF work because have 2 small different resonators and HF work, max freq I get 28MHZ (49MHz not anymore) but in this HF counter mode is one problem - I can't take measurement near 8MHz and 16MHz. When put this resonators I have ca 800kHz. So what's going on here?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 10, 2020, 08:58:18 am
This is the folder with the custom version. We modified some values of constants, according to the parts on the PCB, values actually measured.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 10, 2020, 09:08:08 am
I can't take measurement near 8MHz and 16MHz. When put this resonators I have ca 800kHz. So what's going on here?

The best way for finding the cause in this case is to start with the hardware. Therefore I asked for checking the oscillators.

BTW, the theoretical maximum of the frequency counter is 1/4 MCU clock * precscaler (for 8 MHz: 2 MHz * 16 = 32 MHz). Based on the ICs used for the oscillators that limit can be lower.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 10, 2020, 09:21:31 am
This is the folder with the custom version. We modified some values of constants, according to the parts on the PCB, values actually measured.
Madires does not yet support Romanian language, so there are compilation errors. Add #include "var_romanian.h" line to variables.h file
I compiled the firmware from your archive, but it is 129% in size and will not fit into ATMega328 memory. You need to disable those options  config.h that you do not use very often.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 10, 2020, 02:12:21 pm
I've added Dumidan's var_romanian.h to the source code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 10, 2020, 05:13:28 pm
indman thanks for the directions. I managed to compile after correcting the omission from variables.h and I changed / supplemented the translation var_romanian.h (it is my contribution to the project, after I check its functionality, I will send it to madires to add it, if it wants).

After reducing the options, I reached "only" 117.9% flash and 102.8% EEPROM.  :D
Let's see what else I get out of the program ...
Beginner's question of m328 programming: can an external 24Cxx memory be used to store some of the program's routines? I know that this way the original hardware configuration is no longer respected, but I would be willing to build a multitester variant with m328p, 24cxx, frequency meter extensions, quartz crystal testing, zenner diodes, optocouplers ...Am I just a dreamer? Or is it possible?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fenichel on October 10, 2020, 09:42:09 pm
  I have one of these testers that I got as a Banggood kit in October 2015.  It was working well, but over a few minutes today the screen lost most, and then all, contrast.  As a result, I can't bring up its menu to adjust the contrast, because I can't tell where in the menu system I am, or if I've even got into it.  Installing a fresh battery doesn't help.

  Because I can't interrogate it through its own menus, I can't tell what version of the software it has.  FWIW, it has a 1" x 2" blue/white monochrome graphic screen and a 28-pin ZIF socket on a 2.5" x 3" red PCB.  The processor is an ATMega328.

  Of course, the display unit could have irreversibly failed, in which case I'll just get a whole new kit from Banggood (or elsewhere, if the old tester hands here have a recommendation).  Before I do that, is there a reset worth attempting?

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 11, 2020, 09:41:29 am
Beginner's question of m328 programming: can an external 24Cxx memory be used to store some of the program's routines? I know that this way the original hardware configuration is no longer respected, but I would be willing to build a multitester variant with m328p, 24cxx, frequency meter extensions, quartz crystal testing, zenner diodes, optocouplers ...Am I just a dreamer? Or is it possible?
All this is possible, but it will be a completely different project with different software. The authors adhere to the original version hardware of the project and this is supported by many. You can use a processor with more memory than the ATMega328 and enable features and modes that do not fit in 32KB of memory. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2020, 09:57:30 am
indman thanks for the directions. I managed to compile after correcting the omission from variables.h and I changed / supplemented the translation var_romanian.h (it is my contribution to the project, after I check its functionality, I will send it to madires to add it, if it wants).

If you send me an updated version I'll add it.

Beginner's question of m328 programming: can an external 24Cxx memory be used to store some of the program's routines?

The ATmega's architecture doesn't support that. Better go for an ATmega644 or 1284.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 11, 2020, 09:57:53 am
I've added Dumidan's var_romanian.h to the source code.

Thanks madires for adding, but i think the file is only valid for ver. 1.40m. I am attaching the translation for 1.41m which has some modifications, according to the original from English.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2020, 10:06:04 am
  I have one of these testers that I got as a Banggood kit in October 2015.  It was working well, but over a few minutes today the screen lost most, and then all, contrast.  As a result, I can't bring up its menu to adjust the contrast, because I can't tell where in the menu system I am, or if I've even got into it.  Installing a fresh battery doesn't help.

  Because I can't interrogate it through its own menus, I can't tell what version of the software it has.  FWIW, it has a 1" x 2" blue/white monochrome graphic screen and a 28-pin ZIF socket on a 2.5" x 3" red PCB.  The processor is an ATMega328.

Could be a bad display. If you post a picture of your tester we might be able to tell you the display controller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 11, 2020, 10:41:58 am
@madires:

To clarify any confusions, I am attaching the files with the Romanian translation for the 1.40m and 1.41m versions. I also tried a size optimization using some abbreviations. I will try to do translations in Romanian for the next versions as well - if Karl agrees, I will translate the last 2-3 versions of it plus the following ones. A good day!
Title: Reply to #6540
Post by: Fenichel on October 11, 2020, 04:37:58 pm
  Thanks for your rapid response.  Here are two pictures of my tester, one complete, and one with the display removed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2020, 05:02:45 pm
That's an M328Kit with an ST7565 based 2.4" display (SPI interface).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fenichel on October 11, 2020, 05:20:40 pm
That's an M328Kit with an ST7565 based 2.4" display (SPI interface).
OK.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 11, 2020, 06:37:02 pm
Basically you can use any supported display with an SPI interface as a replacement. You just need to compile a new firmware with the matching driver enabled. It's up to you to decide whether to buy a replacement display or a new tester. If you go for a new tester I'd recommend one with an ATmega644 and a rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 12, 2020, 08:09:29 am
  I have one of these testers that I got as a Banggood kit in October 2015.  It was working well, but over a few minutes today the screen lost most, and then all, contrast.  As a result, I can't bring up its menu to adjust the contrast, because I can't tell where in the menu system I am, or if I've even got into it.
You need to understand the reason why the display has lost image. If you have a multimeter, then first of all you can check the + 5V supply voltage, which goes to the LM1117 integrated stabilizer. The output of the stabilizer should be 3.3V. I have shown in the photo the points that need to be checked.You can also check the voltage that should come to the display backlight. The backlight LED may be damaged  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fenichel on October 12, 2020, 11:30:50 pm
  Thanks for your interest.  The voltages at U1 are 3V3 and +5V as they should be.  At BL, I see +2.65V.   The VSS & VDD points are GND and +5V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 13, 2020, 07:12:11 am
Fenichel,the display is likely to be working properly. When you press the Test button, does the display backlight come on? You can try to update the ATMega328 firmware located here
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on October 13, 2020, 01:29:25 pm
The TC-1 has a color display, IR receiver module and boost converter for the Zener check (up to about 35V). And it comes with an ATmega324 or 644
Can't that Zenerboost be used for TRIACS as well?

TC1 with 644? I think that would be the best base device to start with at the moment. I couldn't find one though. Anyone know a reliable source for TC1/644 devices?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fenichel on October 13, 2020, 03:40:16 pm
Thanks again for your help.
When you press the Test button, does the display backlight come on?
Yes, it does.
Quote
You can try to update the ATMega328 firmware located here
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_st7565_kit/)
I'll try that, but I'm pessimistic.  The fact that the contrast took a few minutes to go away, instead of being lost all at once, makes me believe that it is more likely to be a hardware trace giving up its last thread than a cosmic ray fouling the software.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 13, 2020, 03:54:21 pm
I'll try that, but I'm pessimistic. 

Hope dies last! At the very least, you will know that you have checked all possible causes of the malfunction. :)
A few more tips - look carefully at how the flat cable that leads to the display is sealed. Very often, simple soldering brings the display to life. Also check if any standard LED blinks if you insert it into test contacts 1-2 (1-3) and press the Test button.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fenichel on October 13, 2020, 07:38:31 pm

look carefully at how the flat cable that leads to the display is sealed.  Very often, simple soldering brings the display to life.
Your remark is apt, but the cable's soldering looks OK, even under magnification.
Quote
Also check if any standard LED blinks if you insert it into test contacts 1-2 (1-3) and press the Test button.
Yes, it does.  I think that there must be a hardware failure in the innards of the display.  I'll get a replacement to see if that works.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 14, 2020, 09:58:37 am

Can't that Zenerboost be used for TRIACS as well?

NOT! Because the test component is connected to and powered from the MCU ports, so with voltages between 0V and 5V. The testing of zenner diodes is done with a voltage of 30-40 V generated by an external MCU boost converter; the voltage is measured by resistive divider, so as not to exceed 5V on the MCU input. They are physically separate circuits.

If you have knowledge of electronics, study the original project documentation - you can find it here: https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Doku/trunk/pdftex/english/)

You will need to download all the content > click on Download GNU tarball. For unzip I recommend 7zip - or any program that can handle .tar and .gz archives.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on October 16, 2020, 11:50:53 pm
Sorry, I don't have a guide about creating fonts. As a starting point please see bitmaps/font_8x8_hf.h. I think the GLCD Font Creator is able to create the right bitmap format (export as TFT / new GLCD). For linux/unix users I've written a small command line tool to convert bit and byte orders of a character bitmap (hexadecimal input and output).
Is it possible to convert the fonts back from C to bmp to get an overview of all bitmaps?
Where can i find your tool to convert bit/byte order?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 17, 2020, 10:31:38 am
Is it possible to convert the fonts back from C to bmp to get an overview of all bitmaps?

You could enable SW_FONT_TEST to see the complete font or write a small tool.

Where can i find your tool to convert bit/byte order?

I haven't published it yet. Would you like a copy (no docs, besides the source code)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on October 17, 2020, 10:51:03 pm
Actually i wanted to create a comparison sheet to get a glimpse how all the fonts look like. But i probably have to go for 8x8 fonts/24x24 symbols on GM328A anyway to get enough room to put all the fun stuff into it (8x8 usually looks best anyway). So maybe its not necessary. I don't have a device yet though. Did you ever consider adding RLE compression for the bitmaps?

What do you think about sound feedback? Those little pc speaker tweeters are multifreq and cheap. Static resistor ranges could be mapped to predefined frequencies so a detected 4.7kOhm would always give the same freq beep (say 400Hz), 10kOhm maybe 800Hz so you could identify them (or get a feeling in what range you are) even before looking at the screen. Cap charging could be reflected in realtime (sweeping up sound) so one could actually hear the inner workings of the device. Just a wild thought though. Just reminded me on the old 8Bit computers where we sent the uncrunching data (beside copying it to ram where it belonged) to sound chip to hear the data. You could hear load errors/bad data or if you exceeded ram area. It was a nice debugging feature and cool to hear the true machine workings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 18, 2020, 10:51:33 am
I had some thoughts about compressing the bitmap data, but in this case there are more drawbacks than benefits. The compression would even increase the bitmap size. When I get a new toy, the first thing after unboxing is to disable acoustic feedback. >:D Some like it - I hate it. Anyhow, several measurements and functions are time-critical and won't allow any additional fancy beeping. But it can be added to others, and you need a dedicated PWM output.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jotka13 on October 18, 2020, 01:49:49 pm
Hello everybody,

I am new in this forum, so far I always looked at Mikrocontroller.net for the Transistor Tester AVR. Because of the last posts there, I have now also become aware of this forum here.

It seems to me that it is even more extensive than the forum on Mikroontroller.net. The English language does not make it easier for me.

I have now searched here for layout designs for PCBs to reproduce for the different versions of the transistor tester, but unfortunately I have not found them yet.

Maybe you have one or the other hint for me, if I can find them here at all, which ones are already available here or how I should have searched to find them myself.

Many thanks to you already!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 18, 2020, 02:43:45 pm
You'll find examples for PCBs at https://www.mikrocontroller.net/svnbrowser/transistortester/Hardware/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Hardware/) or https://github.com/madires/Transistortester-Warehouse/tree/master/Hardware. (https://github.com/madires/Transistortester-Warehouse/tree/master/Hardware.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on October 18, 2020, 03:31:11 pm
And there's Indman's comparison table (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3267562/#msg3267562) for the clones. Scroll down two posts. Not really "PCB layouts" though in case you want true templates for DIY.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rhb on October 18, 2020, 07:08:56 pm
FWIW  A suggested FW enhancement.

I am trying to learn RF amplifier design.  A key requirement for estimating the input impedance is the base spreading resistance and the forward biased base emitter resistance. 

I have means for measuring this using my 34401A, but it would be nice if the LCR tester software would report  rbb and rbe or rbb + rbe in addition to Vbe and Ce, the emitter diffusion capacitance, as currently reported by my BSIDE ESR02 Pro.  For details c.f. "RF Circuit Design" by Chris Bowick p 99 (1st ed) or p 105 (2nd ed).

My Peak Atlas LCR45 also reports complex impedance and other information if you press a button after the initial reading.

Part of my project is to compare the accuracy of HF designs using DC or low frequency measurements to VNA results and actual amplifiers built using the measured transistors.  Though widely used at HF, general purpose transistors such as the 2N3904/6 and 2N2222 don't give S or Y parameters for HF

Have Fun!
Reg
Title: Re: $20 LCR ESR Transistor checker project
Post by: uski on October 19, 2020, 08:01:56 am
what is the advantage of the crystal? Do you get more accurate results?
No, I did not notice any significant difference in the stability and accuracy of the readings between the ceramic and quartz crystal.
The main advantages of a ceramic crystal are small dimensions, there is no need for precise adjustment after installation, and also fewer parts on the board.
But the frequency at which the crystal operates has a noticeable effect on the measurement results.
Previously, my AY-AT had a 20MHz crystal. I noticed that the tester was unstable at this frequency.
Most of the Chinese-made ATMega328 processors are very unstable at 20MHz. This is especially noticeable when measuring the ESR of capacitors.
At 16MHz, these same processors work much more stable and predictable.  :)

Could this be related to the ADC clock ?
An unstable CPU would create many other issues than just problematics measurements.
However, an overclocked ADC can totally explain unstable measurements but an otherwise stable system

Have you tried to reduce the ADC clock with the 20MHz crystal and see if it solves the problem ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 19, 2020, 08:40:43 am
Have you tried to reduce the ADC clock with the 20MHz crystal and see if it solves the problem ?
I already wrote before that all measurement problems are solved by setting the clock frequency to 16MHz.
I am not interested in other experiments with ADC. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 19, 2020, 09:10:07 am
I have means for measuring this using my 34401A, but it would be nice if the LCR tester software would report  rbb and rbe or rbb + rbe in addition to Vbe and Ce, the emitter diffusion capacitance, as currently reported by my BSIDE ESR02 Pro.  For details c.f. "RF Circuit Design" by Chris Bowick p 99 (1st ed) or p 105 (2nd ed).

I can't promise anything, but I've noted down your suggestion.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 19, 2020, 02:01:20 pm
Could this be related to the ADC clock ?
An unstable CPU would create many other issues than just problematics measurements.
However, an overclocked ADC can totally explain unstable measurements but an otherwise stable system

Have you tried to reduce the ADC clock with the 20MHz crystal and see if it solves the problem ?

The ATmega's datasheet states that the maximum ADC clock is 200 kHz for a resolution of 10 bits. For an MCU clock of 8 or 16 MHz the ADC clock is set to 125 kHz, and for 20 MHz it's set to 156.25 kHz. Since the ADC prescaler can't go higher than /128 it's not possible to lower the ADC clock for an MCU clock of 16 or 20 MHz any further. And it doesn't matter much as long as the ADC clock stays lower than the supported maximum.

Another point to note is the maximum MCU clock. IIRC, some ATmegas max out at 16 MHz, also the new 328 types which don't have the "full swing crystal" option anymore. If you have any problems with 20 MHz move to 16, as indman recommends.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on October 20, 2020, 11:25:56 pm
1) When upgrading a GM328A to 16MHz is just the crystal to be swapped? Nothing else (beside software)?
2) Do i have to swap the crystal on the dev board as well?
https://www.aliexpress.com/item/32657285482.html (https://www.aliexpress.com/item/32657285482.html) (ATmega8 ATmega48 ATMEGA88 Development Board AVR)
3) Is the ISP/dev board flash method able to rescue the chip in case the fuses were set wrong? I can't remember the name anymore but if i reckon correctly there is another flash method for avr (that is able to flash the chip in all cases). The flasher i want to get is this:
https://www.aliexpress.com/item/32670511994.html (https://www.aliexpress.com/item/32670511994.html) (USBASP USBISP AVR Programmer ATMEGA8 ATMEGA128)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 21, 2020, 05:27:19 am
1) When upgrading a GM328A to 16MHz is just the crystal to be swapped? Nothing else (beside software)?
Yes.
2) Do i have to swap the crystal on the dev board as well?
https://www.aliexpress.com/item/32657285482.html (https://www.aliexpress.com/item/32657285482.html) (ATmega8 ATmega48 ATMEGA88 Development Board AVR)
No.
3) Is the ISP/dev board flash method able to rescue the chip in case the fuses were set wrong?
No.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on October 22, 2020, 12:52:02 am
Thanks. Just for reference, the other method is high voltage programming and seems to be a much more complex process (usually not necessary indeed). I will stick with the standard ISP.

1) Why are the GM328A DIY kits more expensive (9.80Eur DIY vs 5.80Eur SMD)? Any specific reason? My pick would be the pre-assembled.

2) I can't see it on the pictures. The pre-assembled version needs 16MHz SMD (not DIP) quartz crystals, right? I mean, the Atmega is still a DIP. They could have put the quartz up on purpose as DIP as well for easier modding.

3) None of the sellers explicitly mention the calibration parts (short/loop cable, resistor, capacitor) or the 9V battery buckle. Did anyone get them along with the GM328A?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 22, 2020, 10:15:24 am
1) Why are the GM328A DIY kits more expensive (9.80Eur DIY vs 5.80Eur SMD)? Any specific reason? My pick would be the pre-assembled.

The DIY variant has THT components, while the SMD variant has SMD components; THT components are more expensive than SMD ones, hence the price difference.

2) I can't see it on the pictures. The pre-assembled version needs 16MHz SMD (not DIP) quartz crystals, right? I mean, the Atmega is still a DIP. They could have put the quartz up on purpose as DIP as well for easier modding.

The quartz crystal will also be 8 MHz, this is the designed scheme and the Chinese manufacturers respect it exactly. If it is the SMD variant already assembled, I expect the MCU to be also SMD, not DIP. Chinese manufacturers do not worry at all that the user would like to make moddings, they choose the cheapest option of production.

3) None of the sellers explicitly mention the calibration parts (short/loop cable, resistor, capacitor) or the 9V battery buckle. Did anyone get them along with the GM328A?

Those who sell GM328 are not the ones who produce them, most of the time they have no idea what they are selling !! So .... hence the setup instructions!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on October 22, 2020, 02:54:04 pm
The quartz crystal will also be 8 MHz,
I want to upgrade it from 8 to 16MHz. Thus i need to know what to buy (THT or SMD).

I expect the MCU to be also SMD, not DIP.
I don't think so. Look at the pictures below. Even though you can just see the backside you can clearly see 2x14 THT pins. That should be the MCU.
https://www.aliexpress.com/item/33036516954.html (https://www.aliexpress.com/item/33036516954.html)

1) Is the quartz SMD or THT?
3) Is the MCU socketed already?


Edit: Found this (https://dragaosemchama.com/en/2019/04/gm328a-reverse-engineering-new-firmware-and-tetris/). Looks like both are THT and MCU is socketed already.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 22, 2020, 03:34:46 pm
Maniaxx
Chinese clones GM328A (B) may have several configuration hardware. In the photo that I attached, you can see the SMD MCU.
If this is important for you, then check with the seller which option will be sent to you after purchase. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 22, 2020, 05:32:52 pm
I have means for measuring this using my 34401A, but it would be nice if the LCR tester software would report  rbb and rbe or rbb + rbe in addition to Vbe and Ce, the emitter diffusion capacitance, as currently reported by my BSIDE ESR02 Pro.  For details c.f. "RF Circuit Design" by Chris Bowick p 99 (1st ed) or p 105 (2nd ed).

I can't promise anything, but I've noted down your suggestion.

I've looked into the suggestion. AFAICS, the Transistortester's hardware isn't able to measure those parameters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on October 23, 2020, 04:51:42 am
So problem is when put 7-9MHz and 15-17MHz HF crystal, tester show wrong value (300-800kHz) and when put osc. probe directly to crystal during the measurement scope show correctly value. There is something with the wrong reading. Can anyone check it? Max read freq on BNC mode is 1MHz?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 23, 2020, 09:17:20 am
As far as I know, the maximum frequency that can be measured by the basic scheme is 2MHz. That's why the extension for checking quartz crystals has a prescaler that can be set to a factor of 1:16 or 1:32 with a hardware jumper. But the prescaler option in the software must be activated. Did you activate the option? Or go 1: 1?
The prescaler can be used both for BNC input and for checking LF and HF quartz crystals.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on October 23, 2020, 03:08:40 pm
I haven't any hardware jumper. I guess. I just set software prescaler 1:16 (tip in file "Clones"), tester have soldered 8MHz crystal to ATMega.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 23, 2020, 07:45:12 pm
So problem is when put 7-9MHz and 15-17MHz HF crystal, tester show wrong value (300-800kHz) and when put osc. probe directly to crystal during the measurement scope show correctly value. There is something with the wrong reading. Can anyone check it? Max read freq on BNC mode is 1MHz?

The next step is to check the output fed into PB0 / T0.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 25, 2020, 11:29:19 am
I haven't any hardware jumper. I guess. I just set software prescaler 1:16 (tip in file "Clones"), tester have soldered 8MHz crystal to ATMega.

Please detail a bit what hardware version you have? Is it bought ready assembled? Is it made by you? If so, what scheme?
I know that when you ask for help on a forum, as an unwritten rule you have to give details about the problem, details of what you tried and what you got. No offense, yes?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Ricky25 on October 30, 2020, 03:38:03 am
Hello friends,

i have (tried) to read up the thread (searched, checked indman Table of clones, ...) , but still cant find what is the best LCR to buy at this moment (or link to aliexpress) with support the firmware updates posted here.
Looks like i have to spend a little bit more time, but advice what to buy would be really helpful.

I did come as far as this  ::) : TC-T7-H
https://www.aliexpress.com/item/4001208715581.html (https://www.aliexpress.com/item/4001208715581.html)

Thx
R.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 30, 2020, 09:54:42 am
Do you need an LCR meter and/or a component tester?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Ricky25 on October 30, 2020, 10:46:51 am
I would like to have a component tester (LCR functionality would be nice to have too :) ). They have today 20% for everything sold on AliExpress, would order one today.
I have read here a lot of comments about T1 / T7 and Bside ESR02 Pro, but could not read/figure out an "advice" for what to buy (with m/k firmware support).

R.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 30, 2020, 03:41:04 pm
The problem with recommending a specific clone is that there isn't any perfect or all-in-one tester. It's always a trade-off. The TC-1/T7 has the nasty U4 (a small MCU controlling power and test button) which needs to be reprogrammed or replaced with a small circuit. The Bside ESR02 Pro has only basic features. The Hiland M644 comes with the extended frequency counter, but no case and no LiPo. And there's the AY-AT (GM328A) which is still a good choice if you don't need a nice case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 30, 2020, 04:40:38 pm
Hello friends,
i have (tried) to read up the thread (searched, checked indman Table of clones, ...) , but still cant find what is the best LCR to buy at this moment (or link to aliexpress) with support the firmware updates posted Thx

I believe that since we have 2 respected authors of the project and 2 firmware versions, it will be reasonable to purchase several devices from Chinese friends that will complement each other. Considering the very low price at present, which essentially amounts to the price of component parts, this will be a small investment that will quickly pay off. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on October 30, 2020, 06:03:33 pm
And there's the AY-AT (GM328A) which is still a good choice if you don't need a nice case.
There are cases for the GM328A.
https://www.aliexpress.com/item/33036516954.html (https://www.aliexpress.com/item/33036516954.html)

Or are they that bad not worth to mention?

And yes, that's my favorite as it has color display and (in my opinion) the best h/w layout (more connectors for freq in/out, 9V plug, no LiPo (unnecessarily dangerous)).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Ricky25 on October 30, 2020, 07:17:34 pm
Thank you very much for your answers, i would start with a TC-T7-H :) .
Can i use the K/M firmware updates on that device?

Thx
R.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 30, 2020, 07:52:17 pm
Ricky25
Read my message carefully here https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2910034/#msg2910034 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg2910034/#msg2910034)
TC-T7H will most likely be equipped with a 128x128 display with an unknown controller. Therefore, the firmware update on this clone will not be possible until the controller type is recognized. Clones TC-1 are most preferred for buying and updating the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 02, 2020, 06:13:03 pm
I need to know (not guesses please):

Can this LCR-T4 tester output logging via UART, and how would this be accomplished, please?

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2020, 06:36:43 pm
Yep:
- find an unused I/O pin
- add a pull-up resistor to the pin (many TTL-serial2USB adapters will also work fine without the pull-up)
- compile k or m-firmware with the software UART enabled (set pin and features)
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 02, 2020, 07:33:06 pm
Yep:
- find an unused I/O pin
- add a pull-up resistor to the pin (many TTL-serial2USB adapters will also work fine without the pull-up)
- compile k or m-firmware with the software UART enabled (set pin and features)

Trawling through the "Make" file and the others, put my mind in a spin... not sure which bits to flip, which code to change etc...  :-\
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2020, 07:35:20 pm
k or m-firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 02, 2020, 08:13:34 pm
k or m-firmware?

How does one know?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2020, 08:25:31 pm
So you're running the modified firmware which came with the T4?
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 02, 2020, 08:31:27 pm
So you're running the modified firmware which came with the T4?

Yes
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2020, 08:36:52 pm
For serial output you need to choose between k and m-firmware. Are you familiar with compiling software and programming ATmegas?
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 02, 2020, 08:51:25 pm
For serial output you need to choose between k and m-firmware. Are you familiar with compiling software and programming ATmegas?

I know what commands to run, I can compile, yes, I just got thrown by all the serial options. As for what firmware I need, I found this in my email...

"TransistorTester 328p_st7565 1_13k r713"
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 02, 2020, 09:10:56 pm
That's the k-firmware which uses PC3 as serial output. Edit the Makefile and uncomment "CFLAGS += -DWITH_UART".
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 02, 2020, 09:45:36 pm
That's the k-firmware which uses PC3 as serial output. Edit the Makefile and uncomment "CFLAGS += -DWITH_UART".

Thanks so much! I now have serial data coming out into "minicom", via my Bus Pirate (in "transparent UART" mode) @ 9600Kbps!
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 03, 2020, 08:07:37 pm
I have two of these component testers:

#1: The one my UART enquiry was about (ST7565 LCD - gorgeous green screen)
#2: A "Fish8840" type tester, colour LCD, in a black case


On tester #2 (Fish8840), the ". . ." when it's testing the component is animated with growing periods ("."     ". ."   ". . ." etc) and also animates over serial. On tester #2, it is a static ". . ." symbol, which is fine on the LCD, but shows a non-printing characted over serial (attached). Any ideas how I can animate the ". . ." on tester #1?

@@ Also, you may have surmised, I got serial working on tester #2 (Fish8840) but I don't like this unit that much - it blew the "Z14" 3.3v reference when I first flashed a new firmware, and... well, I don't use it.

@@ Error? @@
Unit #1 (green screen, LCR-T4) complains with the message below, after each test when I give a long press for a subsequent test:

"Not calibrated!                                                                 
For calibration clamp                                                           
the 3 pins together                                                             
and start with                                                                 
the key. Acknowledge                                                           
the self-test with                                                             
the key within 2s.                                                             
Disconnect pins after                                                           
                                                                               
the message                                                                     
"isolate Probe!" is                                                             
shown. Software and                                                             
documentation is at                                                             
svn://                                                                         
mikrocontroller.                                                               
net/transistor tester "
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 03, 2020, 08:26:03 pm
On tester #2 (Fish8840), the ". . ." when it's testing the component is animated with growing periods ("."     ". ."   ". . ." etc) and also animates over serial. On tester #2, it is a static ". . ." symbol, which is fine on the LCD, but shows a non-printing characted over serial (attached). Any ideas how I can animate the ". . ." on tester #1?

AFAIK, the k-firmware just displays "...". The animation could be a modified firmware.

@@ Error? @@
Unit #1 (green screen, LCR-T4) complains with the message below, after each test when I give a long press for a subsequent test:

"Not calibrated!                                                                 

Simply run the calibration. Please see https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/ttester-1.13k.pdf.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on November 04, 2020, 10:37:58 pm
Something is with Your fw or my config because now I try with fw 1.13k Karl and all it's ok. I try Your older fw. I test 16MHz crystal and oscillation is correctly but LCD show wrong value. See picture.
(http://[attachimg=1])
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 05, 2020, 02:49:34 am
Something is with Your fw or my config because now I try with fw 1.13k Karl and all it's ok. I try Your older fw. I test 16MHz crystal and oscillation is correctly but LCD show wrong value. See picture.
(http:// (Attachment Link) )

? Expand please.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on November 05, 2020, 08:16:50 am
On my new from Ali Hiland M644 with ST7565R and 8MHz crystal i can't test correctly in HF mode crystal in terms of 7-9MHz and 15-17MHz because LCD show wrong value like 10kHZ. Oscillations are correct (see picture in previous post - tests 16MHZ there) just LCD show wrong value on fw 1.41m. On fw 1.13k this is not a problem. Can anyone check it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 05, 2020, 11:29:30 am
I can reproduce that issue with my Hiland M644. For crystals around 8 or 16 MHz the difference to 8 or 16 MHz is displayed instead of the real frequency. I don't see that on another tester with an ATmega644 running at 16 MHz. I'm curious what causes this strange issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on November 05, 2020, 10:09:23 pm
Hmm, interesting. Is better 16MHz crystal than 8MHz in Atmega644? More precise?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 05, 2020, 10:44:39 pm
I've found the cause and I'm working on a fix now. An MCU clock of 16 MHz doubles all frequency ranges (signal gen and frequency counter) and helps a little bit with some measurements.

Update: Fixed! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 06, 2020, 07:39:17 pm
Modified my LCR-T4 with the addition of an "HC-06" bluetooth module. Set the baud to 9600 and changed the name to "LCR-T4", tapped the serial O/P of the MCU and fed it to a 3K3 + 2K2 potential divider, to drop the UART level to a safe level for the "HC-06" bluetooth module (accepts 3.3V nominally), tapped off pin 10 of MCU to power the module only when the LCR-T4 is turned on, and finally connected to it over bluetooth, using "Serial Bluetooth Terminal": https://play.google.com/store/apps/details?id=de.kai_morich.serial_bluetooth_terminal&hl=en_GB&gl=US

Oh, and mounted the PP3 battery clip OUTSIDE the casing... duh.

Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on November 07, 2020, 12:46:41 am
nice. What serial app is that?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 07, 2020, 02:48:11 pm
... and with an ATmega644 plus m-firmware you can enable remote commands and run Messtechniker's tools (for Windows) or write your own tool to control the tester. Haven't seen any app for mobile phones yet. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 07, 2020, 07:30:25 pm
nice. What serial app is that?

If you read my post, the link is at the top :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 09, 2020, 07:47:48 pm
Okay, which version of the firmware is this as shown in the attached photos? This is the **original** firmware on my LCR-T4 which it came with, and to be honest, the graphics are MUCH clearer & nicer, and the calibration procedure MUCH simpler and more intuitive.

I'd like to find out which version this is so that I may enable UART on that (like I did in my previous post, the other day) and enable the sub-menus.

Ideas? Thanks! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 09, 2020, 08:35:01 pm
That's a modified k-firmware with a fancy GUI. Unfortunately the manufacturer of that clone didn't publish the modified source. The drawback of the fancy GUI is a higher flash usage, i.e. less flash for features (the ATmega328 has only 32kB flash memory).
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 09, 2020, 10:21:51 pm
That's a modified k-firmware with a fancy GUI. Unfortunately the manufacturer of that clone didn't publish the modified source. The drawback of the fancy GUI is a higher flash usage, i.e. less flash for features (the ATmega328 has only 32kB flash memory).

As I'd surmised, thanks. Okay, so bearing that in mind, how do I calibrate the device when using my compiled firmware, so that the calibration process is as easy as it is on the supplied firmare? It's rather vague and cryptic on the custom one - the supplied firmware may be "dumbed down" but the calibration is MUCH easier to accomplish
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 09, 2020, 10:33:08 pm
In case of the k-firmware you can trigger the calibration by shorting all three probes or via the menu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 10, 2020, 12:17:13 am
In case of the k-firmware you can trigger the calibration by shorting all three probes or via the menu.

Thanks. Was aware. I was asking how it can be made as simple and painless to calibrate as the retail firmware, not how to invoke it.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 10, 2020, 10:29:37 am
Don't both use the same process?
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 10, 2020, 06:41:16 pm
Don't both use the same process?

Technically, maybe, but not UI and simplicity-wise.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 11, 2020, 10:05:14 am
Unless you've enabled SHORT_UNCAL_MSG the k-firmware shows a text explaining the calibration process if the tester isn't calibrated yet. And during the calibration it tells you what to do anyway.

BTW, most people call it calibration, but it's actually an adjustment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on November 11, 2020, 10:08:57 am
... how do I calibrate the device when using my compiled firmware, so that the calibration process is as easy as it is on the supplied firmare? It's rather vague and cryptic on the custom one ...

Have you tried to calibrate the newly installed firmware? What exactly seems "vague and cryptic" in reading what is written on the screen / what exactly does the device ask for? The first time he asks you to summarize the 3 testers - after that he continues alone until the step when he asks you to remove the short of the testers ... What is cryptic here? Or do you say so, unproven? How simple do you want the procedure to be? Have a voice command like "Hey, tester, calibrate yourself!", Or how?   8)  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 11, 2020, 08:55:38 pm
... how do I calibrate the device when using my compiled firmware, so that the calibration process is as easy as it is on the supplied firmare? It's rather vague and cryptic on the custom one ...

Have you tried to calibrate the newly installed firmware? What exactly seems "vague and cryptic" in reading what is written on the screen / what exactly does the device ask for? The first time he asks you to summarize the 3 testers - after that he continues alone until the step when he asks you to remove the short of the testers ... What is cryptic here? Or do you say so, unproven? How simple do you want the procedure to be? Have a voice command like "Hey, tester, calibrate yourself!", Or how?   8)  :-DD

Mock me if you will, but I feel you have misunderstood which firmware version I find cryptic - the supplied, retail unit firmware "Mtester" is not the one I am having issues with, as you implied.

No need to be a wise guy.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on November 12, 2020, 10:54:50 am
I probably misunderstood due to a mistranslation - I'm not a native English speaker. That's it, google translate also makes mistakes ... Please accept my apologies, I didn't mean to make fun of you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on November 12, 2020, 06:36:26 pm
I probably misunderstood due to a mistranslation - I'm not a native English speaker. That's it, google translate also makes mistakes ... Please accept my apologies, I didn't mean to make fun of you.

I forgive you, don't think about it any more, we all make errors, you didn't mean to :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: cigmas on November 17, 2020, 11:55:21 pm
Would one of these units be suitable for in-circuit testing for failed capacitors? If so, which model?

I don't foresee needing an ESR meter often, but if it can be had for a budget price, it would be a nice asset. So much the better if it comes with other potentially useful (diagnostic) features for which I couldn't justify buying a dedicated, more professional device given my usage level.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2020, 09:53:15 am
Kinda. The test voltage could be too high to get meaningful results when semiconductors are in parallel. A special low-voltage ESR meter would be better. All clones of the Transistortester (ATmega328 or better) are able to measure capacitance and ESR.
Title: Re: $20 LCR ESR Transistor checker project
Post by: cigmas on November 18, 2020, 08:57:25 pm
Kinda. The test voltage could be too high to get meaningful results when semiconductors are in parallel. A special low-voltage ESR meter would be better. All clones of the Transistortester (ATmega328 or better) are able to measure capacitance and ESR.

Any specifically recommended (budget) products? I'm really not familiar with these devices.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 19, 2020, 10:52:21 am
No, but you'll find usually some hints about pros and cons of various testers in the last 10 pages.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bateau020 on November 19, 2020, 05:18:08 pm
Budget: one often mentioned candidate is the "Bob Parker ESR" meter. EVB meters make them for example. 2 digits, 10mOhm resolution at the lowest range. Simple, fast, and easy to use: 1 button. But lots of others are mentioned over here.
Personally I have it, but it gets less use since I got myself some LCR Research Pro tweezers (somewhat budget), as that is much more versatile, and smaller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: cigmas on November 19, 2020, 10:10:21 pm
Budget: one often mentioned candidate is the "Bob Parker ESR" meter. EVB meters make them for example. 2 digits, 10mOhm resolution at the lowest range. Simple, fast, and easy to use: 1 button. But lots of others are mentioned over here.

That one looks great and is designed specifically for in-circuit capacitor testing. The problem is with the "budget" definition going an order of magnitude more than the title of this thread. Looks like it won't be any cheaper than ~$150 CAD + shipping/etc, and that would be if it were not sold out. https://flippers.com/catalog_oc/index.php?route=product/product&path=675&product_id=64 A bit difficult to justify for occasional hobby use.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bateau020 on November 20, 2020, 06:29:06 am
Yes indeed, it is not in the price range of the title, although I got one in europe for 65% of the price you mentioned.
How about the MESR-100? That is around 35 USD. Getting closer. Don't know if it is any good though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 20, 2020, 09:49:22 am
If you like to discuss other ESR meters then please start a new thread to keep this one focused.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vague on November 27, 2020, 06:57:06 pm
Hi
Can the AY AT colour kit be fitted with a fixed calibration capacitor or does it need a chip with more pins?
Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 27, 2020, 07:54:27 pm
The fixed cap for self-adjustment needs an ADC pin and an I/O pin for the resistor. Therefore it's an option for an ATmega324/644/1284 based tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on November 28, 2020, 12:24:09 am
Probably another stupid question but...

Why does my GM328A only occasionally read the ESR of caps?

I cannot work out any pattern to this. All caps read the capacitance accurately and leakage current, but only sometimes will measure the ESR.

My instinct says that this isn't a fault - I think there must be an explanation for this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 28, 2020, 07:01:23 am
de_light, what capacitors are you measuring? If the ESR of the capacitor is close to zero, then on the m-firmware it is not always displayed as a result on the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 28, 2020, 12:28:24 pm
... or when the ESR measurement detects invalid values. Do you use an SMPSU to power the tester?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on November 28, 2020, 05:59:31 pm
...Why does my GM328A only occasionally read the ESR of caps?
I cannot work out any pattern to this.
The manual says "Measurement of ESR value of capacitors with value of above 20nF ."
So, the occasion may be the "capacitors with value of above 20nF. "
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on November 28, 2020, 11:29:59 pm
I've tried with both a 9V and standard 'wall-wart' SMPSU for the DC in.

Here are some examples:

Salvaged 6800uF/63V cap from an 80s device - reading 6026uF, ESR of 0.00 and iLeak of 36uA
Second salvaged cap as above, reading 6195uF, ESR 0.00 and iLeak 30uA

New 470uF/100V cap - 444.8uF and iLeak 3.55uA, no ESR displayed
Salved 1000uF35V - 888 uF, iLeak 15.98uA and no ESR displayed
New 1000uF/16V - 946 uF, iLeak 11.23uA no ESR displayed
Film polypropylene unknown capacitance, old - 1030nF ESR 0.03
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2020, 12:09:11 pm
Film polypropylene unknown capacitance, old - 1030nF ESR 0.03

That's way too low. Have you run the self-adjustment?
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on November 29, 2020, 12:54:58 pm
I did run it immediately after upgrading stock firmware. It completed without issue.

I have rerun the adjustment now and it completed fine.

Film cap ESR now reading 0.38
Big old salvaged caps still reading 0.00 Ohms  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 29, 2020, 02:57:48 pm
de_light,compare the readings of your capacitors with the measurements on BSideESR02. If they are of the same order, then everything is fine with your clone. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2020, 04:01:22 pm
Film cap ESR now reading 0.38
Big old salvaged caps still reading 0.00 Ohms  :-//

A bit more reasonable, but still too low for a low value film cap. A good 4.7mF cap has around 0.02 Ohms, so your 6.8mF cap could be 0.01 which is the lowest value the tester can measure. In that case 0.00 Ohms (which means <0.01) would be fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on December 02, 2020, 04:25:19 pm
My ESR results from LCR meter and compensated Hiland M644, all cap's are electrolytic and used condition:
6800uF 50V
(http://[attachimg=1])
(http://[attachimg=2])
1000uF 25V
(http://[attachimg=3])
(http://[attachimg=4])
100uF 16V
(http://[attachimg=5])
(http://[attachimg=6])
and 0,47uF 50V
(http://[attachimg=7])
(http://[attachimg=8])
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 02, 2020, 04:57:16 pm
Szybkijanek
This is not an entirely correct comparison for measuring ESR. Madires notes in the instructions that:
"The tester tries to measure the ESR for capacitors with more than 10nF.
But since the ESR measurement isn't done via an AC signal with a
specific frequency, please don't expect a solid result. The method used might
be comparable with a 1kHz test."
The capacitance value for electrolytic capacitors is usually measured at a frequency of 100-120Hz.
Your LCR meter must not only have AUTO mode, but also MANUAL to select the measurement frequency. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on December 02, 2020, 05:02:57 pm
All measurements was in manual mode but only 4 test was with 1,2kHz. First 3 cap's was in 100Hz mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 02, 2020, 07:22:43 pm
... and you should carefully select the right measurement mode (series/parallel) based on the impedance if supported by the LCR meter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on December 02, 2020, 07:32:13 pm
Ofcourse, I do this, with this original table:
(http://[attachimg=1])
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 02, 2020, 09:16:25 pm
Maybe you've already seen one of the cheap PIC LC meters which are based on a simple LC oscillator circuit. I've started to work on implementing the same measurement method with the LC oscillator as a hardware option. It's meant as option for ATmega644/1284 based testers. If you like to build one please find the schematic attached.

EDIT: C4 is the reference cap, not C3
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on December 03, 2020, 12:11:28 pm
I have LC-100A, it,s STM8 based LC meter but this meter have very bad accuracy (maybe only my model), before buying LCR meter I measure L element with scope method, accuracy ca. 5% when compare with professional LCR meter and software modeling, the smallest value I could measure is 20nH.
https://circuitdigest.com/electronic-circuits/how-to-measure-inductance-or-capacitance-using-oscilloscope (https://circuitdigest.com/electronic-circuits/how-to-measure-inductance-or-capacitance-using-oscilloscope)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 03, 2020, 01:52:59 pm
Maybe you've already seen one of the cheap PIC LC meters which are based on a simple LC oscillator circuit. I've started to work on implementing the same measurement method with the LC oscillator as a hardware option. It's meant as option for ATmega644/1284 based testers. If you like to build one please find the schematic attached.
Madires, what LC range are you planning to use with this option?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 03, 2020, 02:42:24 pm
The ranges of the PIC LC meter are 10nH - 100mH and 0.1pF - 900nF with a reference frequency about 595kHz. If you take 600,000 Hz as reference frequency and 599,999 Hz for the lowest possible L or C which can be measured, the ranges could go down to about 0.2nH and 3.3fF theoretically. At the moment the m-firmware starts at 10nH and 0.1pF, same as the PIC LC meter, and I have to figure out what the feasible limits are. The math provides more digits, but how many are reasonable for the measurement? The upper limit for inductance is higher than 100mH, possibly 150mH (have to check). And for capacitance I've ran into an issue with the output signal for caps above 22 or 33nF. Rising and falling edge start to have some "kinks" causing the frequency counter to see more pulses than there really are.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 03, 2020, 06:09:50 pm
Some updates. 150mH work fine (around 12kHz), and lower limits of 1nH and 10fF seem to be reasonable. I'm not sure, but the PIC LC meter uses a gate time of 100ms for the frequency counter while the m-firmware uses auto-ranging with 100ms and 1s. So we get a better frequency resolution for low value L/Cs. The auto-ranging for the LC frequency counter does exactly the opposite (longer gate time for high frequencies) of what a normal frequency counter would do (longer gate time for low frequencies). ;D The LC meter code increases the firmware size by about 5.5kB.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 04, 2020, 05:29:22 am
Some updates. 150mH work fine (around 12kHz), and lower limits of 1nH and 10fF seem to be reasonable.
Madires, i don't really need a 10fF measurement, but I am very interested in stable results when measuring 1-10nH. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on December 04, 2020, 06:46:27 am
Quote
stable results when measuring 1-10nH
I do not think that it would work on this tester because for such a resolution you need high accuracy and physically the equipment does not allow it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 04, 2020, 07:23:06 am
I do not think that it would work on this tester because for such a resolution you need high accuracy and physically the equipment does not allow it.
This is very possible without the use of expensive equipment! But on condition that not cables for connection are used, but fixed measuring contacts. Check out these links. The usual standart arduino is used.
https://soldernerd.com/2014/12/14/arduino-based-inductance-meter/
https://soldernerd.com/2017/01/29/standalone-inductance-meter-on-a-etched-board/
These schemes can be further simplified, as done on the Russian-language forum VRTP.ru. But this is already a separate topic for discussion. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on December 04, 2020, 08:51:34 am
Hmm, not bad, so we need at least 1MHz frequency for measurement 1nH inductor according to the table below:
(http://[attachimg=1])
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 04, 2020, 11:20:17 am
1 MHz could be possible. The self-adjustment checks the base frequency of the LC tank (just L_i and C_i) and also the frequency with the reference cap C_p connected. I'll use constants you can easily change if you like to use other values for L_i and C_i to increase the base frequency. The math is explained in the source. So you just have to calculate the two frequencies and update the constants for the limits.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 10, 2020, 12:27:48 pm
Maybe you've already seen one of the cheap PIC LC meters which are based on a simple LC oscillator circuit. I've started to work on implementing the same measurement method with the LC oscillator as a hardware option. It's meant as option for ATmega644/1284 based testers. If you like to build one please find the schematic attached

I've messed up C3 and C4, so here's the updated version:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 20, 2020, 10:00:26 pm
Happy holidays!

v1.42m
- Updated 6x8 fonts (thanks to Bohu).
- New ISO8859-2 based 6x8 font (FONT_6X8_ISO8859_2_HF, thanks to Bohu).
- Added LC meter hardware option (HW_LC_METER). It's based on a simple LC oscillator circuit, similar to some inexpensive LC meter kits.
- Changed Display_Value() to support also fempto (f).
- When CYCLE_MAX is set to 255 the automatic power-off is disabled and the tester keeps running until it's powered off manually.
- Fixed issue with display of strange frequencies in the extended frequency counter in a specific situation (reported by zybkijanek@EEVblog). Also changed display output of a missing signal or a too low frequency from '0Hz' to '-'.
- The basic counter displays now a '-' instead of '0Hz' in case of a missing signal or a too low frequency.
- Added option to display I_C/I_E test current for hFE measurement (SW_HFE_CURRENT, suggested by Obelix2007@EEVblog). Also added corresponding remote control commands (I_C and I_E).
- Added Romanian texts (thanks to Dumidan@EEVblog).
- Added configuration switch for ESR tool (SW_ESR_TOOL, suggested by indman@EEVblog).
- Changed text output of E series norm values to also display unit (suggested by indman@EEVblog).
- Updated alternative Polish texts (thanks to Jacon@EEVblog).
- Last text line on display was simply overwritten when UI_KEY_HINTS is enabled (reported by Obelix2007@EEVblog). Added function to wait for user feedback before clearing last line.
- Updated Spanish texts (thanks to pepe10000@EEVblog).
- Corrected error in "#define" for E96 norm values (reported by Obelix2007@EEVblog).
- Added driver for ILI9488 based displays (8/16 bit parallel and 4-line SPI, thanks to Bohu for a sample display).

Please download at https://github.com/madires/Transistortester-Warehouse (https://github.com/madires/Transistortester-Warehouse) or https://www.mikrocontroller.net/svnbrowser/transistortester/. (https://www.mikrocontroller.net/svnbrowser/transistortester/.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 21, 2020, 08:01:42 am
Hi Madires! Thank you for great work and another gift for the New Year and Christmas! :-+

I have a question on the README documentation:
"The PIC LC meters usually have measurement ranges of 10nH to 100mH, and 0.1pF
to 900nF. They seem to use a gate time of 100ms for the frequency counter.
The m-firmwmare uses auto-ranging with gate times of 100ms and 1000ms to
improve the resolution for low value L/Cs. Thus the ranges start at about 1nH
and 10fF. The maximum inductance supported is roughly 150nH. Regarding
capacitance I've run into an issue with my PCB. At around 33nF the output
signal starts having some spurs in the rising and falling edges causing the
frequency counter to see more pulses than there really are. Could be a problem
with my PCB layout. Despite that, the maximum should be around 900nF (beyond
that the LC oscillator will become unstabe). "

Is everything correct with the maximum inductance and capacitance values? 150nH or 150mH? 900nF?
Perhaps a faster and more modern comparator could be tried in the LC meter design instead of the outdated LM311?
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 21, 2020, 10:01:51 am
Hello Madires, thanks for the new firmware, I am attaching the new Spanish language file with the latest improvements that you have added.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 21, 2020, 10:57:38 am
Is everything correct with the maximum inductance and capacitance values? 150nH or 150mH? 900nF?
Perhaps a faster and more modern comparator could be tried in the LC meter design instead of the outdated LM311?

The maximum for inductance is around 150mH. "nH" is a typo. And the maximum for capacitance is around 900nF as long as the LC oscillator has a clean output signal. A larger capacitance causes the LC oscillator to stop. Modern comparators should work fine too. I was simply too lazy and used the well known circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 21, 2020, 12:41:05 pm
And the maximum for capacitance is around 900nF as long as the LC oscillator has a clean output signal. A larger capacitance causes the LC oscillator to stop.

Madires, it is a known issue for LM311 based generators. Take a close look at the LC / ESR meter schematic I made a few years ago. Pay attention to the resistor R17, the role of this resistor is to remove parasitic surges at the signal edges, which appear just at low oscillation frequencies. This allows (in addition to the chain) to increase the upper limit of measurements by about 5 ... 6 times. Also look closely at the feedback loop of elements C19-R16-L3. My upper limit of measurements of non-electrolytic capacitors reached 50μF. I have attached a photo below.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jacon on December 21, 2020, 10:28:52 pm
Hi Madires,

Thank you for such nice Christmas gift  :-+
Enclosed please find updated Polish language translation file.

Greetings
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on December 22, 2020, 04:08:20 am
Sorry for being out of sync in the Q&A but does anyone have a link to a good eBay seller with a recommended modified k-version with the fancy GUI?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 22, 2020, 07:34:23 am
Electro Fan
What do you mean by a fancy GUI? Do you need a multifunctional tester with working options or a beautiful interface?
Give an example of an upgraded k-firmware? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on December 22, 2020, 05:02:37 pm
Electro Fan
What do you mean by a fancy GUI? Do you need a multifunctional tester with working options or a beautiful interface?
Give an example of an upgraded k-firmware? :)

Hi indman,

Thanks for your reply.  And thanks for all your good leadership on the LCR ESR Transistor checker project.

I’ve been following this thread for a long time and recently thought it might be time to see if there is some consensus on “a” or “the” preferred tester.  Rather than reading all 250 plus pages I decided to read from the end to see if I could find some recent consensus.  (After 7 years of this thread I’m guessing the answer is “it depends”, and that the testers keep evolving.)

My sense is that different users want different testers for different purposes, of course.  Some might want an inexpensive versatile tester to get good enough measurements for various tests on various devices.  Others might want a tester that is somewhat open source / modifiable to meet particular requirements or because they enjoy modifying test equipment.  Others, like myself, might be interested primarily in the educational opportunities this class of testers (and test equipment) in general can provide.

In any event, on page 265 I saw a reply from madires to an inquiry by eti regarding the particular firmware on a particular device (I think a LCR-T4) in which madires said “That's a modified k-firmware with a fancy GUI.” – so I figured those might be somewhat definitive terms, but maybe they haven’t been officially confirmed terms. :)  In any event, armed with a descriptor of something that looked interesting I worked my way further back in the thread and was happy to find on page 261 a link to your good pdf summary.  Nice work, thanks!

With these good breadcrumbs I then shelled out to eBay and found a bunch of alternatives including some GM328, GM328A, GM238A+, and LCR-T4.  I’m not wedded to these models, whatever model make sense is cool.  These are just some examples, they are nearly dart throws that happened to land somewhere in the vicinity of the target.

What I’m looking for is a device that tests a wide range of components (don’t even really care which exactly because at the prevailing prices if necessary 2 or 3 might fit in the budget).  The main objective is to find one or more testers that provide a UI with schematic-like symbology to help tie the measured values to the internal circuitry and performance attributes of the DUT.

While it would be great to find a tester that does “everything” (measures many values for many devices) and that has highly accurate test results those are not my primary objectives.  (Not to mention "does everything" and "with high accuracy" don't seem like reasonable asks for a $20 tester.)  My preferred tester is a tester that will provide useful educational feedback about at least some popular devices (transistors, inductors, capacitors, resistors, etc.) and that helps tie the measured values to the particular device leads (especially for various types of transistors, of course).  I have a couple Peak Atlas products and I find the symbolic plus measured value display, and the physical to logical (socket/lead) ties in their UIs to be helpful when studying (or trying to teach) the characteristics of DUTs.

Of course it would be nice if the tester had a decent case to hold the battery and DUT in place and knobs and buttons that fit human fingers, etc. but my primary interest is a highly informative user interface, especially the display.  If there is such a device that comes to mind and it has the good house keeping seal of approval of the users in this thread that would be ideal as having access to the users here is almost as valuable (or more valuable) as the device itself.

Thanks in advance for any particular product recommendations or any other guidance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 22, 2020, 07:55:32 pm
In any event, on page 265 I saw a reply from madires to an inquiry by eti regarding the particular firmware on a particular device (I think a LCR-T4) in which madires said “That's a modified k-firmware with a fancy GUI.” – so I figured those might be somewhat definitive terms, but maybe they haven’t been officially confirmed terms. :)  In any event, armed with a descriptor of something that looked interesting I worked my way further back in the thread and was happy to find on page 261 a link to your good pdf summary.  Nice work, thanks!

Chinese friends have been selling the LCR-T4 tester with modified firmware for more than 5 years and it remains the most popular and affordable device today.
And many of its owners are still sure that it was invented and developed by Chinese engineers, and that everything that was released later was LCR-T4 clones!  :-DD
But, those who have been familiar with the topic for a long time, knows perfectly well who is actually the author of this wonderful project and makes a huge contribution to its further development.
I believe that despite a very rich selection of different clones, the most convenient and informative in every sense is a device that you make with your own hands and mind.
Trust me, it will bring you much more knowledge, benefit and good mood than the purchased device.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on December 22, 2020, 11:59:06 pm
So setting aside the build vs buy already made for the moment, is the LCR-T4 your top recommendation?  Or is there another model you prefer?  Thx
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 23, 2020, 06:50:19 am
etc. but my primary interest is a highly informative user interface, especially the display.  If there is such a device that comes to mind and it has the good house keeping seal of approval of the users in this thread that would be ideal as having access to the users here is almost as valuable (or more valuable) as the device itself.
If so, the LCR-T4 is almost perfect for your interests.
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 23, 2020, 08:23:10 am
I bought the m328 kit because it's easier to mod (no SMT), socketed mcu , included rotary enc, and because it's a kit I can throw away the sh***y components right off the bat.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on December 24, 2020, 06:55:39 am
I also prefer socketed vs SMD.

I’m sure it’s in here somewhere but what are the key distinctions between the m328 and LCR-T4?  Thx
Title: Re: $20 LCR ESR Transistor checker project
Post by: Electro Fan on December 24, 2020, 07:08:57 am
There's a common misunderstanding about the Transistortester being an LCR meter. It isn't, but it can measure L, C and R within some limits, and the k-firmware's SamplingADC function allows to measure also low value L/Cs. Inexpensive LC meters like the LC-100A are basically a simple LC oscillator plus a frequency counter. The Transistortester is presumably a little bit more accurate for capacitors above 1µF. Proper LCR meters, for example DER-EE DE-5000, apply an AC signal and measure voltage and current.

The AY-AT/GM328A is a nice general purpose Transistortester clone. However, I'd recommend to get a proper LCR meter if the LC-100A doesn't work for you.

I’m obviously jumping around in this thread trying to get up to speed on the basics of the thread but just wanted to say this is very helpful:

There's a common misunderstanding about the Transistortester being an LCR meter. It isn't, but it can measure L, C and R within some limits, and the k-firmware's SamplingADC function allows to measure also low value L/Cs. Inexpensive LC meters like the LC-100A are basically a simple LC oscillator plus a frequency counter. The Transistortester is presumably a little bit more accurate for capacitors above 1µF. Proper LCR meters, for example DER-EE DE-5000, apply an AC signal and measure voltage and current.

Thx

PS, if this thread had it’s own sticky this would be a good sticky
Title: Re: $20 LCR ESR Transistor checker project
Post by: timelessbeing on December 25, 2020, 02:28:06 am
See indman's post from Oct 8 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3268064/#msg3268064) for a PDF comparison of clones
Title: Re: $20 LCR ESR Transistor checker project
Post by: Ser9ei on December 28, 2020, 01:18:31 pm
Hello!
where can i find a sample (photo) of implemented devices (testers) with the new "hardware lc-meter" feature from the latest firmware 1.42m?
Thanks a lot and sorry if it was already here, but i am a new member of this forume, and here are a lot of pages on this thread)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 28, 2020, 02:36:54 pm
Welcome to the forum! There aren't any testers yet which come with the LC oscillator circuit, but you can build the oscillator on a piece of perfboard. And also have a look at the changes suggested by indman a few posts back.
Title: Re: $20 LCR ESR Transistor checker project
Post by: brunosso on December 29, 2020, 11:04:01 am
How to set the makefile for the MK-328 tester? This tester is in the Clone PDF but not in the Clones setting file
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 29, 2020, 11:24:55 am
Following might work for the display:
Code: [Select]
#define LCD_ST7565R
#define LCD_GRAPHIC                     /* graphic display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD0            /* port pin used for /RES */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
//#define LCD_OFFSET_X                    /* enable x offset of 4 dots */
#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
#define FONT_8X8_VF                     /* 8x8 font */
#define SYMBOLS_24X24_VFP               /* 24x24 symbols */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SI         /* port pin used for MOSI */

And for the TL431 enable HW_REF25. If you have a working config please send me the required settings and I'll add them to the Clones list.
Title: Re: $20 LCR ESR Transistor checker project
Post by: brunosso on December 29, 2020, 12:00:57 pm
This config works at least for the LCD:

Code: [Select]
#define LCD_ST7565R                     /* display controller ST7565R */
#define LCD_GRAPHIC                     /* graphic display */
#define LCD_SPI                         /* SPI interface */
/* control and data lines */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD0            /* port pin used for /RES (optional) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (data input) */
/* display settings */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
//#define LCD_OFFSET_X                    /* enable x offset of 4 dots */
//#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
/* font and symbols: vertically aligned & flipped, bank-wise grouping */
//#define FONT_6X8_VF                      /* 6x8 font */
#define FONT_8X8_VF                     /* 8x8 font */
//#define FONT_8X16_VFP                   /* 8x16 font */
//#define FONT_6X8_ISO8859_2_VF           /* 6x8 Central European font */
//#define FONT_8X8_ISO8859_2_VF           /* 8x8 Central European font */
//#define FONT_8X12T_ISO8859_2_VFP        /* thin 8x12 Central European font */
//#define FONT_8X16_ISO8859_2_VFP         /* 8x16 Central European font */
//#define FONT_8X8_WIN1251_VF             /* 8x8 cyrillic font */
//#define FONT_8X8ALT_WIN1251_VF          /* 8x8 alternative cyrillic font */
//#define FONT_8X8T_WIN1251_VF            /* thin 8x8 cyrillic font */
//#define FONT_8X12T_WIN1251_VFP          /* thin 8x12 cyrillic font */
//#define FONT_8X16_WIN1251_VFP           /* 8x16 cyrillic font */
#define SYMBOLS_24X24_VFP               /* 24x24 symbols */
/* SPI bus */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SI         /* port pin used for MOSI */

For the TEST button how can i enter in the submenu with options and AutoTest?!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 29, 2020, 12:09:06 pm
Two short key presses after the display of the last component found (it's explained in the README file).
Title: Re: $20 LCR ESR Transistor checker project
Post by: brunosso on December 29, 2020, 04:19:21 pm
Thank you madires!
After a few try i'm happy with this config!

config.h
https://pastebin.com/kha1USWv

config_328.h
https://pastebin.com/GPFL1GYy

Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on December 30, 2020, 12:17:46 pm
https://soldernerd.com/2014/12/14/arduino-based-inductance-meter/
https://soldernerd.com/2017/01/29/standalone-inductance-meter-on-a-etched-board/

These URLs do not work ....  Can't find the server!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on December 30, 2020, 12:40:18 pm
Hello madires! I have attached the updated file for the Romanian language according to the new version.
These days I have time to see how the new version runs on my AY-AT 328 tester. I come back with the results.

A new year better and more abundant to you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 31, 2020, 05:14:10 pm
https://soldernerd.com/2014/12/14/arduino-based-inductance-meter/ (https://soldernerd.com/2014/12/14/arduino-based-inductance-meter/)

These URLs do not work ....  Can't find the server!
An alternate copy of this server
https://www.radiolocman.com/shem/schematics.html?di=162628 (https://www.radiolocman.com/shem/schematics.html?di=162628)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 02, 2021, 03:00:13 pm
Film cap ESR now reading 0.38
Big old salvaged caps still reading 0.00 Ohms  :-//

Another user had a similar issue with some larger electrolytics and missing ESR readings. It turned out to be a lack of 100nF bypass caps for VCC and AVCC.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 04, 2021, 05:27:32 pm
Update on the L/C meter's LC oscillator: I tried several modifications for a cleaner output signal but they didn't help much and had an impact on the frequency. The best way to clean up the output signal is to add a Schmitt trigger logic gate (for example 4093) or a second comparator. This way I was able to measure caps up to 120nF. Beyond that the oscillator became unstable. So I'm wondering how the PIC based L/C meters can achieve 900nF using the same circuit. When the oscillator would run stable the theoretical maximum values supported by the m-firmware would be 250mH or 3.5µF (low frequency limit of 10kHz).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jerby on January 04, 2021, 08:16:16 pm
I have the DIY Kit "AY-AT" / GM328A (or Color kit) and upgraded from v1.13 to 1.42. V1.13 is working ok, but  v1.42 (after calibration) gives too high capacitor values (50%) and does not recognize resistor of 22K and more 10k and lower seems ok. And it measures capacitor (8pF) between probes 1 and 2 when nothing is connected. What parameters could be set wrong?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 04, 2021, 09:11:52 pm
Could be a clock mismatch. Which value have you set for FREQ in the Makefile? Does it match the quartz crystal?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jerby on January 05, 2021, 09:39:45 am
Thanks Madires, but both are 8Mhz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 05, 2021, 10:00:12 am
I have the DIY Kit "AY-AT" / GM328A (or Color kit) and upgraded from v1.13 to 1.42. V1.13 is working ok, but  v1.42 (after calibration) gives too high capacitor values (50%) and does not recognize resistor of 22K and more 10k and lower seems ok. And it measures capacitor (8pF) between probes 1 and 2 when nothing is connected. What parameters could be set wrong?
Do hardware tests T1-T6 and show us the results. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on January 06, 2021, 11:03:11 pm
I bought 2 of the Chinese clones in December 2020 from 2 different Amazon vendors.  Both are NO-NAME on PCB and No version on screen (just Mtester).

Also they BOTH have one obvious difference from the various easy to find schematics and PCB pictures: in place of the diodes D1 and D2, there are resistors that occupy that space but are oriented 90 degrees vs. the diodes (220 ohm and 330 ohm listed on the silkscreen).

Anyone know about this?  Is this a different display?

I've tried 3 different candidate firmwares, but nothing comes up on the display.

Back light does come on, and (once I think) it went off after about 95 seconds if I do nothing with 1,2,3 shorted.  Or maybe not.

I tried thomas from here
https://www.mikrocontroller.net/topic/248078?goto=4120737#4105488 (https://www.mikrocontroller.net/topic/248078?goto=4120737#4105488)

I tried
transistortester-trunk.tar.gz\trunk\mega328_T3_T4_st7565 - TAR+GZIP archive, unpacked size 6,013,626 bytes

And I tried
TT_Gelb_german.zip

Perhaps my mistakes are obvious to someone more versed than myself?
I stumbled through programming with a JATGICE3 and got the hex and eep to verify. 
I used thomas for fuses (
efuse:0x04
hfuse:0xd9
lfuse:0xf7
)

Anything I should look for with a 'scope to detect progress through the code execution?

Thanks!

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 07, 2021, 08:00:37 am
Hi mrmox!
You have a really small variation on one of the most popular T4NoStripGrid clones!
For this clone, you must use the firmware from the trunk \ mega328_T4_v2_st7565 folder
But there is one important note!
The tester has started, but the contrast is very low, the text is barely visible. The voltage across the 330/220 Ohm divider is 2.04 V. In order to comfortably read the screen, the contrast value had to be raised to the limit, i.e. 63.
Therefore, when the contrast value in the firmware is equal to 40, almost no symbols are visible and you have to peer very closely at the screen, trying to see the menu items. The decision how to raise the contrast when first turned on after the firmware was simple. You just need to swap the resistance of the divider. Then the voltage at its point is 3.04 V. Now, with a contrast value of 40, you do not need to twist anything, everything is perfectly visible (which pleases with repeated flashing). Those who purchase the same tester with the same divider can immediately throw over these resistances, and not be tormented trying to read the menu. With native Chinese firmware, everything read perfectly. Those with contrast issues with the same screen should check the screen voltage. It should be 3-3.3 V.
If desired, the XC6206 30-33 stabilizer fits well (diagonally) in place of these resistances.  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jerby on January 07, 2021, 01:38:56 pm
I have the DIY Kit "AY-AT" / GM328A (or Color kit) and upgraded from v1.13 to 1.42. V1.13 is working ok, but  v1.42 (after calibration) gives too high capacitor values (50%) and does not recognize resistor of 22K and more 10k and lower seems ok. And it measures capacitor (8pF) between probes 1 and 2 when nothing is connected. What parameters could be set wrong?
Found out that issue is caused by changing the "#define UREF_VCC" to the actual Li-ion voltage of 4150mV. When I set to 5000 resistor and capacitor measurements are ok but battery voltage is way to high.
Question: what changes are required to use Li-ion battery and 5V regulator removed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 07, 2021, 02:28:14 pm
The 5V regulator is required for proper operation. If you want to modify the tester for a Li-Ion cell you need a boost converter to feed the 5V regulator. The battery monitoring is a different story. The AY-AT/GM328A uses a voltage divider at PC5 to be able to deal with 9V batteries. You can keep it that way and change BAT_WEAK and BAT_LOW to match your Li-Ion battery. Or you could remove the divider since the battery's voltage is lower than 5V, and change the monitoring mode to BAT_DIRECT. However, you need to modify the battery monitoring circuitry to monitor the Li-Ion cell instead of the 9V input (after T3). And there are two obstacles more, power management circuitry and preventing the Li-Ion cell being drained when the tester is powered off.

@All: If you have modified your tester please tell us what you've changed (schematics are great for that) when asking for support.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jerby on January 07, 2021, 02:52:59 pm
Hi Madires, thanks again for your very quick reply. I will take the route of the step-up convertor and install the 5V regulator back. I already changed BAT_WEAK and BAT_LOW to match my Li-Ion battery. I didn't modify the tester, only removed the 5V regulator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on January 08, 2021, 04:24:21 am
Thanks so much indman!
I had gotten so close, I could have smelled success, but I needed you to push me over the finish line!
I had looked in transistortester-trunk\trunk\mega328_T4_v2_st7565\
But there was (and is) NO ReadMe.txt!  So I scratched my head and moved to the next one.

Who can I lobby to put in a ReadMe.txt for the next novice to come along? 
I volunteer to write it (by using YOUR words, ha ha!).

I did swap the resistors, and got the .hex and .eep files.
I have to JUMPER THE BUTTON CLOSED to keep the power on so I can program with my JTAGICE3.
Then I programmed mega328_T4_v2_st7565.hex
Then I programmed mega328_T4_v2_st7565.eep
Then I checked the Fuses and they were still:
EXTENDED = 0xFC (valid)
HIGH = 0xD9 (valid)
LOW = 0xF7 (valid)
(although thomas suggests efuse:0x04.  I will look at that tomorrow!)

I pulled off the programming connector and button jumper, then I fired it up (with a long push opf the button?  Or maybe just a push..)
And I got  words on the screen!  Now I will practice:
The Art of Engineering: Making something you want out of things you can get!


Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 08, 2021, 07:58:07 am
Who can I lobby to put in a ReadMe.txt for the next novice to come I volunteer to write it (by using YOUR words, ha ha!).

You can assume that I wrote to you in my message the contents of the ReadMe.txt file. :D
You can pass it on to other inheritance newbies.  :D
Most importantly, the device is now working as intended! Fuses no longer need to be changed - they are correctly programmed with you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on January 09, 2021, 05:21:13 pm
BUILDING FROM SOURCE  (ELI5)

I will share my stumbles before getting COMPILE FROM SOURCE working.

I had WinAVR-20100110 from some distant past installed on my PC, and I *hoped* it would generate identical code to the .hex and .eep in trunk

I was stumped when there was NO SOURCE that I could associate with my particular variant although I could find the .hex and .eep and a Make file within \trunk\mega328_T4_v2_st7565.
And I KEPT READING "just run the Makefile in Programmers Notepad" (=PN) that I finally realized COMES WITH WINAVR.
Even though I could see NO SOURCE CODE, I decided to try to RUN THE MAKEFILE to see if an error would enlighten me.

I launched PN.  I opened the Makefile from \trunk\mega328_T4_v2_st7565 in PN.  I clicked Tools/Make All.

Well it DID give me an error that was a clue.  The error said there was NO ../setup.mk
So.... the Makefile wanted to FIND A FILE in a directory ABOVE where the Makefile lived!  How would THAT HAPPEN?
And so it came to me that I NEEDED TO EXPAND THE WHOLE TRUNK on my disk instead of just fumbling around in the tarball looking for pieces that I thought were applicable.  Now I think I understand how the whole system for variants is made to work.  Simple really; silly of me to be looking for complexity!  All sources are in \trunk directly, all Makefiles are in subdirectories.

I decided to expand it to a memory stick to avoid cluttering my main PC even more.  After the WHOLE trunk tree was resident on the stick, I THEN opened (in PN) the Makefile that was within the directory for my variant:
I:\jays_lcr_t4\trunk\mega328_T4_v2_st7565\Makefile
Next (in PN) I ran Make All and got this familiar error:
0 [main] sh 9104 sync_with_child: child 15176(0x1E4) died before initialization with status code 0xC0000142
I say familiar since apparently many many people have had to find this  msys-1.0.dll file and place it as directed:

I found solution.
Copy this file:
http://www.madwizard.org/download/electronics/msys-1.0-vista64.zip (http://www.madwizard.org/download/electronics/msys-1.0-vista64.zip)
to utils\bin directory (WinAVR)

I BALKED at taking this random file, and pondered what to do....then I SEARCHED my C:\ drive and found LOTS of them already on my PC.  So I chose what looked like a more recent one (2014!)

And I was about to copy THAT into the location When I saw there was one ALREADY THERE!

Drat! It was going to be so easy!

Now what?  I fretted for a while…..then read so many people saying that it worked for them that I threw caution to the wind and RENAMED the existing file and went ahead and copied the rando different version in.  And it helped, darn it!

Mode                 LastWriteTime         Length Name
----                 -------------         ------ ----
-a----         5/18/2007   7:09 PM         724784 msys-1.0.dll      <---- downloaded from madwizard
-a----         1/19/2010  10:08 AM         781616 msys-1.0.dll.old
-a----         1/19/2010  10:08 AM         781616 msys-1.0HIDING.dll

The Make All succeeded.  I got 2 warnings:

../main.c:480:4: warning: #warning Capacity measurement from high to low not possible for diodes without PULLUP_DISABLE option!
../make_frequency.c:11: warning: 'wish_freq' may be used uninitialized in this function

Did I get IDENTICAL .hex and .eep to the ones in \trunk\mega328_T4_v2_st7565?  WinMerge compare = NO darn it..

There IS a block of identical bytes, starting here

:100070009395E5B8C4B8B6EFB0937A00A5E0A09325

But before & after this block of 19 identical lines, all lines differ.

What about those warnings…..
…OR should I try to update WinAvr?

Lemme look!  Well no info on warnings I could see.  And a mass of entanglement trying to research if I was using exactly the same version of WinAVR/gcc/??? as was used in \trunk.

I decided to change the word "Bat." to "Jay." to prove my compile was taking effect.
Searched for "Bat_str" and found it here:
"I:\jays_lcr_t4\trunk\Battery_check.c"
"I:\jays_lcr_t4\trunk\Transistortester.h"

I went ahead and flashed the code, AND IT RAN!  And it said my name!

I would like to know why my .hex is so different.  It has to be my avr-gcc version, right? 
I need to learn how to update.  Should I uninstall-reinstall WinAVR?

 Directory: I:\jays_lcr_t4\trunk\mega328_T4_v2_st7565

01/8/2021  11:02 PM          86450 mega328_T4_v2_st7565.hex

 Directory of H:\My Equipment\LCR-T4_T3_.....\github\transistortester-trunk\trunk\mega328_T4_v2_st7565

05/13/2020  03:37 AM         83468 mega328_T4_v2_st7565.hex


Thanks again!

Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on January 10, 2021, 07:30:24 pm
Does anyone know if there is a simple mod for finish.mk that will generate an .elf usable for debugging in AS7?

Or another way to get to use ISP debugging?  (I have a JTAGICE3).

Thanks.

Title: Re: $20 LCR ESR Transistor checker project
Post by: dma_k on January 12, 2021, 06:56:21 pm
Maniaxx
Chinese clones GM328A (B) may have several configuration hardware. In the photo that I attached, you can see the SMD MCU.
If this is important for you, then check with the seller which option will be sent to you after purchase. ;)
I have the same board / tester (purchased from here (https://www.aliexpress.com/item/4001331330448.html)). The tester reports firmware v1.12. It has colored display, but does not benefit from that (all information is in one color). I wonder if there is a firmware that takes advantage from colored display? If yes, is there any chance to flash it using the pins PC6/PB5/PB4/... wired on board?

Thanks in advance!
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on January 12, 2021, 08:30:02 pm
ERROR IN WIDELY DISTRIBUTED SCHEMATIC OF CHINESE CLONE [SOLVED]
[LOOK A FEW POSTS AHEAD for revised corrected schematic from Roland]

Years after Roland Elmiger provided a reverse-engineered schematic of a 91make Chinese clone of LCR_T4, I think I have found some missing connections in it!
These would lead the naive (like me) to think there are some unused pins still available!

Does anyone know of a CORRECTED Roland.png somewhere?

PS I have gotten Breakpoint Debugging to work in my no-name chinese clone using debugWIRE with FREE Atmel Studio 7 AS7 (actually called Microchip Studio now).
You will need a device that supports debugging, like the JTAGICE3 I use (some devices are program only).
And now I am not so afraid of bricking the AVR by using debugWIRE (since I do not mess with LOCKBITS).
Unfortunately, it requires DISCONNECTING 3 pins important to the LCR_T4 function, rendering it inoperative as a tester. 
But still useful for those trying to re-purpose this cheap board with display and backlight.

So please check my work, thanks.


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2021, 09:09:18 pm
I have the same board / tester (purchased from here (https://www.aliexpress.com/item/4001331330448.html)). The tester reports firmware v1.12. It has colored display, but does not benefit from that (all information is in one color). I wonder if there is a firmware that takes advantage from colored display? If yes, is there any chance to flash it using the pins PC6/PB5/PB4/... wired on board?

You could try the m-firmware which supports things like color coding for probes or resistor color codes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on January 14, 2021, 05:04:17 pm
CORRECTED SCHEMATIC FOR CHINESE CLONE LCR-T4
from 91make (and others)

It took days of searching for me to FIND the revised corrected schematic.
The errored one is very widely distributed and there are lots of fake russian sites trying to get
you to sign up for some service complete with fake testimonials about how great the service is.

Here I found Transistortester_T4_1d_100dpi.png by Roland dated 29.08.2016 with the corrections
I had proposed (and perhaps more).

https://www.mikrocontroller.net/topic/248078?page=23 (https://www.mikrocontroller.net/topic/248078?page=23)

https://www.mikrocontroller.net/attachment/304138/Transistortester_T4_1d_100dpi.png (https://www.mikrocontroller.net/attachment/304138/Transistortester_T4_1d_100dpi.png)

Best wishes to all.


Title: Frequency counter input voltage
Post by: hobbyist on January 17, 2021, 02:26:29 am
What is the right voltage input for the frequency counter on an AY-AT tester with the M firmware?  The PDF for the K firmware seems to say that the input should be 2.4 volts.  Is it OK to have a sine wave input?  Are negative voltages a problem?  If not, then does the tester expect a frequency that is 0 volts low and 2.4 volts peak?  Do I need to use a Schmitt trigger for low frequencies?  What voltages would damage the tester?   
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 17, 2021, 01:29:18 pm
The frequency counter (pin T0) is triggered by a low signal and the AY-AT has a voltage divider between Gnd and Vcc plus a 100 nF DC blocking cap as input circuitry. Any voltage lower than Gnd or higher than 5 V at T0 can damage the ATmega. If you limit the current the clamping diodes are able to protect the input to some degree. Sine wave is fine, but I haven't tested very low frequencies.
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on January 19, 2021, 10:14:00 pm
Hello Madires,
To compile: Download source from Madires current website.
Download and run AVRSTUDIO 7. Do not choose to install the latest version. Then follow the instructions in:
https://microchipsupport.force.com/s/article/Creating-a-project-from-Makefile-in-Atmel-Studio
Steps for importing makefile project into Atmel Studio :-
Step 1:- Go to Atmel Studio->Tools->Extension and updates->Available Downloads
Step 2:- Install "Create Project from Makefile" extension.
Step 3:- Restart Atmel Studio
Step 4:- Go to Atmel Studio 7->Tools->Create Project from Makefile
Step 5:- Choose the makefile and project name according to the instructions given in the window.
Step 6:- Click "Create Project"
Step 7:- After the project is created it can be built within Atmel Studio itself.
Then add an empty dep subdirectory to remove build errors.
Please can I recommend that you add a blank dep subdirectory to avoid this AVRstudio 7 compile error?

Also, please can you explain how to compile for a particular known model of tester? In my case an ordered T4, I cannot figure it out.
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 20, 2021, 12:12:49 pm
Please can I recommend that you add a blank dep subdirectory to avoid this AVRstudio 7 compile error?

I'll update the Makefile.

Also, please can you explain how to compile for a particular known model of tester? In my case an ordered T4, I cannot figure it out.
Thanks.

Please see the file "Clones" for the settings for your clone and edit config.h and config_328.h accordingly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on January 20, 2021, 03:10:53 pm
Re compile options for T4,
OK, thanks. I will follow that.
Which IDE are you using?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 20, 2021, 06:11:36 pm
A text editor and make - quite spartan.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on January 21, 2021, 03:40:38 pm
Hi.
They gave me a GM328 that they broke when measuring a charged electrolytic capacitor. The SVR05-4 was shorted, and the Atmega was bad too.
I removed the SVR05-4 and the P6KE6V8A since they are not necessary for the proper functioning of the meter, and I programmed another Atmega at 20Mhz (and tested with several) and also changed the Xtal to 20Mhz.
Now it turns on smoothly, but it doesn't work properly.

When I turn on the meter without any components in the measurement socket, it should indicate that there are no components.
Well, it indicates that there are high value resistors or high value capacitors connected.
With normal use of the meter I put components in the socket and except for the capacitors all other components seem to measure well.

The same happens with firm M and firm K, so it is a meter problem.

E measured continuity from the 3 points where the component to be measured is placed to pins 23-24-25 of the Atmega.
From those 3 same points to pins 14-15-16-17-18-19, checking that the resistors are good.

7550 output voltage when measuring component, stable 4.97V.
TL431 output voltage, 2.48V stable.

I would appreciate a help. Thank you

(https://i.ibb.co/f8gjTt5/20210121-125645-copia.jpg) (https://ibb.co/f8gjTt5)   (https://i.ibb.co/rGv477d/20210121-131849-copia.jpg) (https://ibb.co/rGv477d)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on January 21, 2021, 04:13:38 pm
I wonder if we'll see a Raspberry Pi RP2040-based transistor tester? $4 for dual Arms, on-board slave MCU's, and 12-bit A/D's  :-+
https://www.youtube.com/watch?v=o-tRJPCv0GA (https://www.youtube.com/watch?v=o-tRJPCv0GA)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 21, 2021, 04:35:23 pm
TL431 output voltage, 2.98V stable.
I would appreciate a help. Thank you
2.98V or 2.48V?
Show us the T1-T6 hardware test results
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on January 21, 2021, 04:46:45 pm
TL431 output voltage, 2.98V stable.
I would appreciate a help. Thank you
2.98V or 2.48V?
Show us the T1-T6 hardware test results

Sorry 2.48v
I do not understand the hardware results T1-T6
thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 21, 2021, 04:56:49 pm
K-Firmware manual carefully read section 5.5 Selftest Function. M-Firmware has the same section + Self Test
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on January 21, 2021, 06:19:23 pm
Performed test 5.5 in K-Firmware, it is carried out resulting between the test terminals 0ohm.
Performed Self Test with M-Firmware, it performs it with the same result.

But after I test without connecting anything, the problem continues.    :-// :-//     
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 21, 2021, 06:54:18 pm
https://www.youtube.com/watch?v=PS2xatlTWB8 (https://www.youtube.com/watch?v=PS2xatlTWB8)
Full Selfest is performed after entering the main menu of the tester
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on January 21, 2021, 07:25:50 pm
The self-evaluation and calibration is carried out within the menu. It does both without problem but the problem remains.
Firm M only asks for the step of shorting the three terminals, it does not ask for the >100nf and <10nf capacitors. The firm K does ask for the three steps.
I have other GM328 meters, one with the firm K and one with the M and they work fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 21, 2021, 08:32:38 pm
carrascoso, don't you understand me? I ask you to write the results that show the T1-T6 hardware tests! Then the reason why phantom parts are detected with empty test contacts will be clearer. Most likely the reason is a leak on the board or damaged processor ports.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on January 21, 2021, 09:01:27 pm
carrascoso does not seem to appreciate that "the test runs" is not enough!  The test never says "ERROR", it is up to the user to READ THE NUMBERS and compare them to the description of the test.  Often they are reported in mv and the answer is supposed to be a low number for all 3 (like less than 20mv or so...the code author has subtracted off the expected value and is displaying the difference for your convenience).  Other times a value is reported directly.  Best Wishes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on January 22, 2021, 08:56:58 am
Madires
AVRstudio 7 has the advantage of a simulator and, if you have a debugwire adaptor, debug.
AVRstudio 7 requires you to create the Madires  project from makefile.
AVRstudio 7 requires ComponentTester to be renamed ComponentTester.elf for the simulator and debug to work.
I can do this by changing the object file extension in the makefile, see changes below.

Is it possible to change the makefile to generate ComponentTester and ComponentTester.elf for everyone? Makefile is arcane and I checked google and tried CP and XCOPY but failed to replicate the file with a .elf extension.

# link firmware
$(NAME): ${OBJECTS}
    ${CC} ${LDFLAGS} ${OBJECTS} ${LIBDIRS} ${LIBS}  -o ${NAME}.elf


# create hex file of firmware
%.hex: ${NAME}.elf
   avr-objcopy -O ihex ${HEX_FLASH_FLAGS} $< $@

# create hex file of EEPROM data
%.eep: ${NAME}.elf
   -avr-objcopy ${HEX_EEPROM_FLAGS} -O ihex $< $@ || exit 0

# create dump of firmware
%.lss: ${NAME}.elf
   avr-objdump -h -S $< > $@

# output size of firmware and stuff
size: ${NAME}.elf
   @echo
   @avr-size -C --mcu=${MCU} $<


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2021, 10:40:49 am
I could add a new target "elf" to the Makefile. Does a manual "cp ComponentTester ComponentTester.elf" work?
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on January 22, 2021, 04:01:05 pm
Madires,
"I could add a new target "elf" to the Makefile. Does a manual "cp ComponentTester ComponentTester.elf" work?"
Exactly. I tried that but failed to get it to work.

I tried a number of variants suggested by google using CP and XCOPY and COPY and none that I tried resulted in a .elf file with AVRstudio. I am sure that I am making a trivial mistake because I am making random guesses without understanding it.
 
You probably would benefit from using an IDE and AVRstudio has the benefit of a simulator so you can run to a breakpoint and step through your programs without any hardware and, I assume, if you acquire a debugwire interface you can debug the hardware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2021, 04:09:31 pm
Have you tried the "cp ..." in a shell (not via the Makefile)? AVR studio doesn't run on my PC natively. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on January 22, 2021, 06:27:49 pm
Hi.
After doing different tests I had not been able to find the problem. She was even going to make a video calibrating the meter to see if it could be fixed.
I decided to change the socket where the component to be tested is placed.
Due to the tin with which it was soldered (this equipment was given to me already assembled) it has been impossible for me to remove it, but I have been able to remove a lot of tin from the holes.
And in order not to damage the PCB by doing some force, I decided to leave the same socket, but using good quality tin.
And from this moment on, the meter works correctly.
Possibly the problem was the tin with which the assembly was made. If it fails again, I would comment on it again.

Thank you very much for your help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on January 23, 2021, 04:15:48 am
A while after I posted this I realized that the Makefile scheme for the K-firmware and the M-Firmware are vastly different.
I now believe the K-Firmware uses specialized Makefiles for each PCB permutation, while with the M-Firmware
you make #define changes in the config.h and config_328.h files by editing them yourself.
MY COMMENT APPLIES ONLY TO THE  K-Firmware!  (But let me know if I am wrong!)
Sorry if I contributed confusion.



This is working for me to get to breakpoint debugging on hardware but it goes in the finish.mk file

%.lss: $(TARGET)
   $(AVR_TOOL/PATH)avr-objdump -h -S $< > $@
   ls $<
   cp $< ../mega328_T4_v2_st7565/JaysAS7_LCR-T4v2.elf
   @echo JAY thinks he can COPY THE ELF.

size: ${TARGET}

(I included some context) (you will need to adjust it for name)

IIRC, you have to copy it before it gets deleted!

Best All.
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on January 23, 2021, 09:12:40 am
Madires,
Re AVRstudio is not compatible with your computer, that is a shame.
I have used and can recommend Eclipse as a good IDE, but it is a lot more tricky to set up than AVRstudio. Which effort is probably not justified unless it was your job, given that what you do now is working. I find the eclipse forums are far more helpful than I ever found IAR  or Keil. Also I have never used eclipse with debugwire so am not certain of the debug part.

I look back with some nostalgia at AVR MCUs. Having looked afresh I now see limitations of the old AVR MCUs.

AVR studio works fine for me so far with the object file renamed to .elf in the makefile and the empty dep folder. Anyone using avrstudio with your code will find the solution in this forum. So there is no need to solve the copy issue.
Thank you for looking at it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 23, 2021, 03:19:42 pm
I wonder if we'll see a Raspberry Pi RP2040-based transistor tester? $4 for dual Arms, on-board slave MCU's, and 12-bit A/D's  :-+

Nope, the Transistortester needs a 5V MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: scaramonga on January 25, 2021, 10:11:05 pm
Hello all, I was recommended to come here for help, and I hope one of you brainy folks can? :)

I got one of these (GM328), this exact one:https://www.amazon.co.uk/gp/product/B07DJ4DSBH/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

I put it together OK, and it works, sort of, but it keeps alerting 'weak battery 5.6v', even though batteries are brand new, and on DC 7.5-12v its same error, 'weak battery 5.6v'?  It's like its not getting correct voltage.  Screen is a little dim also, but probably due to the max 5.6v problem.

I'm having a stab in the dark and guessing its the 'regulator' (HT7551)?, but then again, I'm probably way off the mark lol!

I'm not as good as you lot, and understand only the basics, so be gentle guys ;)

Any help much appreciated, thanking you kindly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 26, 2021, 07:59:03 am
scaramonga,do you have a voltmeter or multimeter to measure the voltage at the test points of the circuit?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hamlet600 on January 26, 2021, 10:48:47 pm
i have a lcr-t4 and upgrade with both m and k firmware, test all setting for lcd and two lcd pin option but noting show on lcd
even increase contrast number in software .and all thing advised by other user
ps.when i restore factory backup firmware its ok

this is my exact pcb diagram

thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Ser9ei on January 27, 2021, 05:29:31 am
hamlet600,
There are two versions of this t4 clone - “stripGrid” and “noStripGrid”.
Describe of this different you can find in the markus’s manual (see “7.0.3. T3/T4” section in the last version of manual).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 27, 2021, 10:39:45 am
... or read the "Clones" file. If

Code: [Select]
#define LCD_RESET        PD4            /* port pin used for /RES */
#define LCD_A0           PD3            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD1            /* port pin used for SI (LCD's data input) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */

doesn't work please try

Code: [Select]
#define LCD_RESET        PD0            /* port pin used for /RES */
#define LCD_A0           PD1            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD3            /* port pin used for SI (LCD's data input) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
Title: Re: $20 LCR ESR Transistor checker project
Post by: hamlet600 on January 27, 2021, 01:18:45 pm
this was my fist thing to change in firmware( by checking pcb trace Pd4 is not conected anywere) so it should be second pin assignment
also with/without stripgrid option,but no difference.

if something else you could advise its preciated

again big thanks for such a nice project and support :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Ser9ei on January 27, 2021, 02:05:07 pm
hamlet600, please attach your firmware's configuration files here (makefile, config, config328)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 27, 2021, 03:09:08 pm
hamlet600,show a real photo of your clone from the side of the details
Is she the same as here?
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3403834/#msg3403834 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3403834/#msg3403834)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hamlet600 on January 27, 2021, 06:31:27 pm
hamlet600,show a real photo of your clone from the side of the details
Is she the same as here?
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3403834/#msg3403834 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3403834/#msg3403834)
no its not same it hAS 2 SERIES DIODE instead resistor
after all tweaks it show like following display
seems to all pixels are on not just only text
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 27, 2021, 06:42:46 pm
hamlet600, you have a very high contrast! Decrease the contrast value through the main menu of the tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 27, 2021, 06:43:00 pm
The output is shifted by four pixels. If you have LCD_OFFSET_X enabled please disable it (or vice versa). The other issue seems to be the contrast setting. Try to change the contrast via the menu and see if it helps.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hamlet600 on January 27, 2021, 09:16:49 pm
by decreasing contrast to 10 and disable offset_x  and LCD_FLIP_Y everything is ok

is it normal lcd switch off/on by pressing key for move between menu items?

thanks. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hobbyist on January 28, 2021, 04:38:33 am
Hello, what are the advantages and drawbacks of the K firmware vs. the M firmware?  Here is what I know about so far:

K firmware:  Sampling ADC method can measure small capacitors with 0.01 pF resolution.
                    16 MHz maximum clock rate.
M firmware: 20 MHz maximum clock rate.
                   
I have just ordered an AY-AT tester kit and a programming device.  I suppose that either firmware version would work fine.  Would the M firmware give me better options for the device's menus, or the way that the results are displayed?  Are there other advantages to the way that it takes measurements?  Does the faster clock speed give faster measurements? 
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 28, 2021, 06:07:47 am
hobbyist
K-Firmware also supports operation at 20MHz clock rate!
But, most of the Chinese ATMega328 at 20MHz are unstable, so the optimal frequency for both firmware versions is 16MHz. This is the experience that many owners of similar clones have gathered.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 28, 2021, 10:52:07 am
is it normal lcd switch off/on by pressing key for move between menu items?

Yes, the T4's designer replaced the power indicator LED with the LCD's backlight LED to save a few cents.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 28, 2021, 11:08:56 am
Hello, what are the advantages and drawbacks of the K firmware vs. the M firmware?  Here is what I know about so far:

K firmware:  Sampling ADC method can measure small capacitors with 0.01 pF resolution.
                    16 MHz maximum clock rate.
M firmware: 20 MHz maximum clock rate.
                   
I have just ordered an AY-AT tester kit and a programming device.  I suppose that either firmware version would work fine.  Would the M firmware give me better options for the device's menus, or the way that the results are displayed?  Are there other advantages to the way that it takes measurements?  Does the faster clock speed give faster measurements?

As indman already has mentioned, both firmwares support a 20 MHz MCU clock. With the hardware LC meter option (additional circuitry) the m-firmware is also able to measure down to 0.01 pF and 1 nH. It offers many additional features like IR decoder, IR sender, and servo check for example. Simply try both firmwares and choose the one you like. Or buy two clones and run one with the k-firmware and the other one with m-firmware. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 28, 2021, 11:13:01 am
is it normal lcd switch off/on by pressing key for move between menu items?

To eliminate this problem for all clones T4, it is enough to install a 1kOhm resistor in the control circuit of the Test button!  ;)
As a result, when you press the button, the backlight stops turning off and the value of the load current decreases.
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on January 28, 2021, 07:51:18 pm
Madires:
Menu:
Your menu scan method is unusual and clunky. It seems a short press for next item, a long press to select and a double press to exit. It helps to put a resistor in series with the switch, I used 470k to avoid darkening the backlight.
Disabled people (think Professor Hawking) first had electronic scanning with a single switch in 1962, and since then the universal method is to display all the menu options on one screen. Then press(nothing happens)  and release the button to start scanning, indicating each menu item in turn. When you get to the correct menu item press(it stops) and release(it selects the item) Then either an action happens or a new menu appears. You may also need to debounce the switch.
To wake up the LCR T4 press the button. Then do the auto thing. If the button is pressed again go into the menu system. The double click thing is quite hard to do perfectly and is not intuitive.
You could for example have a table of strings to generate the display menu and on selection get a scan number and use a case statement to decide what happens.
Even in 1965 people were dialing numbers with the telephone, changing volume and channel on the TV, writing letters etc.
If you do any work on the menu system, please can I suggest that you consider this option?

I have just bought a LCR T4 with same characteristics as below using LCD_ST7565R as the LCD, the ISP header has pin 1 marked by a square pad and is correct for IDC cable from below, corrected from the LCR T4 png schematic:
 
by decreasing contrast to 10 and disable offset_x  and LCD_FLIP_Y everything is ok



thanks. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 28, 2021, 08:25:33 pm
Would a rotary encoder work for you? It's supported and makes some things more simple.
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on January 28, 2021, 08:28:19 pm
Potential uses of a LCR T4 and similar.
For people experimenting with making their own diodes for crystal sets. Staying on a diode only test is helpful for poking around on a mineral. With a parallel capacitor you could even plot the characteristic. For home made tunnel diodes a large series inductor might be rather better for plotting the characteristics. Then there is finding new mineral combinations. Silicon Carbide LEDS anyone? Home made transistors?

For vacuum diodes (with a separate heater supply) there is also contact voltage and some triodes provide gain at low voltages.For transistors it should be possible to measure switching time and possibly Ft for some. With an extra B-E capacitor perhaps hfe vs collector current.

Couple of other things that might be tested could be capacitor absorption and capacitor non linearity, (capacitance varying with voltage, eg most ceramic types except COG). Again this would involve staying on one test and finding out more about the tested item.
I know, you only have 32k.


Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on January 28, 2021, 08:34:49 pm
Would a rotary encoder work for you? It's supported and makes some things more simple.

Yes, rotary encoder is fine, though I have a T4.
I worked in disability so was trying to pass on some knowledge from that experience.
You may find the odd idea useful, or perhaps not, and I did not mean to offend you.
I am dead impressed with what you have achieved with something so simple.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hamlet600 on January 28, 2021, 10:50:46 pm
is it normal lcd switch off/on by pressing key for move between menu items?

To eliminate this problem for all clones T4, it is enough to install a 1kOhm resistor in the control circuit of the Test button!  ;)
As a result, when you press the button, the backlight stops turning off and the value of the load current decreases.

 AT WHICH POSITION DO YOU MEAN?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 29, 2021, 05:43:45 am
AT WHICH POSITION DO YOU MEAN?
I showed the place with a red arrow  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on January 29, 2021, 09:36:08 am
AT WHICH POSITION DO YOU MEAN?
I showed the place with a red arrow  ;)

I fitted my resistor as shown, but on my T4 I had to cut both the tracks leading to the switch and reconnect the tracks but without the switch using some fine enamelled wire. Then I fitted a 470k resistor from the BL to the switch to replace the cut track. I used a higher value resistor to avoid backlight dimming when switch is pressed. This resistor mod makes using the menu system practical.
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on January 29, 2021, 09:40:03 am
"It is possible to make a transistor using Galena (lead sulfide, PbS). Silvery hunks of Galena are often available from rock shops and science museum stores. You can even make your own by melting sulfur and lead powder over a flame. Look up keywords such as "cat's whisker diode" and "crystal radio" to find out more.
The trick to making a transistor is to use a hyper-clean, freshly-cleaved crystal face, to sharpen your cat's-whisker contacts by dissolving the tips using electrolysis, and then to put the tips within 0.05mm of each other (or preferably within 0.01mm). Obviously the latter is the hardest part. Better use a microscope! The authors of the following article found that the base/emitter junction was critical: it HAD to act as a good rectifier. The base/collector junction wasn't as important. They got some power gain, but their beta was in the single digits. Others have mentioned that if you break open a 1N34 glass diode to expose the Germanium chip, you can make a crude transistor with a similar procedure. Old Germanium audio power transistors probably do the same, while giving much larger semiconductor area on which to play."
"Crystal Triode Action in Lead Sulphide, P. C. Banbury, H.A. Gebbie, C. A. Hogarth, pp78-86. SEMI-CONDUCTING MATERIALS, Conference proceedings, H.K. Henisch (ed), 1951 Butterworth's scientific publications LTD 1951."
From:
http://amasci.com/amateur/transis.html (http://amasci.com/amateur/transis.html)

Note that point contact transistors were formed with a high current pulse which improved the characteristic. They also can have negative resistance effects so the circuits can be different.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Giox040 on January 29, 2021, 11:39:37 am
Hi!
Today rereading the documentation in ctester-1.42m.pdf, I had a doubt about how the adjustment procedure of the Component tester should be performed correctly the first time it is turned on after loading a new firmware.

First I think I have to measure a film capacitor with a value between 100nF and 3.3µF at least three times in a row.

Then I'm not sure if only the "Self Test" or only "Self Adjustment" should be performed, or both should be performed.

Perhaps the only difference between the two is that between the "Self Test" it stores the parameters in the eprom automatically, while with the "Self Adjustment" you must also use the "Save" function?

Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 29, 2021, 05:56:49 pm
The steps are:
- measure a film cap (100nF - 3.3µF) three times (unless your tester has a fixed adjustment cap)
- run the self-adjustment
- save the offset values

The self-test is meant to check the probes in case of strange readings or other issues.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on January 29, 2021, 07:05:47 pm
Stumbling again... if I download a tarball from here
https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/Markus/)

I cannot find ctester-1.42m.pdf!?!?

I thought it would be within ComponentTester-1.42m.tgz but I only see EUPL-v1.1.pdf.

Where should I be looking?   Thanks!



Title: Re: $20 LCR ESR Transistor checker project
Post by: Ser9ei on January 29, 2021, 07:29:36 pm
https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation/English
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 29, 2021, 09:06:34 pm
I cannot find ctester-1.42m.pdf!?!?

The firmware archive includes a "README" file with the documentation, a CHANGES file with firmware changes and the "Clones" file with settings for various clones. The ctester-1.42m.pdf is a compilation of those plus some additional information, done by Bohu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on January 31, 2021, 04:59:28 pm
Is anyone else frustrated that none of the permutations for sale are EXPERIMENTER FRIENDLY? 

Like with the programming connector present and accessible?

And maybe some extra breadboard spots on the PCB?

(or am I just missing this?)

I wonder if one of the (many?) manufacturers could be coaxed into producing such a device?

I have some unspent travel money to help fund such a foolhardy project...anyone have contacts?

Thanks!

 :-DMM


Title: Re: $20 LCR ESR Transistor checker project
Post by: hobbyist on February 01, 2021, 02:11:14 am
mrmox, if you were to put the ultimate transistor tester on the market, here are some cool features that it could include:
-- precision 5 volt regulator
-- high precision resistors
-- header pins for programming
-- a hardwired capacitor for convenient self adjustment
-- a relay to short connections whenever a measurement is not being made, preventing accidental tester destruction
-- an ATMega in a DIP socket so that it can be easily replaced if it ever gets damaged by misuse
-- clear markings to show the connections for frequency measurement, voltage measurement, and function generator
-- a 16MHz crystal
-- the latest M or K firmware
A typical user does not really need all of the above, but there is no reason that a kit or completed device could not have all of the above features.  I would like to buy one. 
Since an ideal tester is not available now, and since I don't quite know how to design my own board, I ordered an AY-AT type of kit from eBay, and precision parts from mouser.com.  Earlier posts from "blurpy" describe what to do, and I expect that it will all turn out quite well.   My tester will not have the relay or the self adjustment capacitor. 
For that matter, if you know how to design a board with all of those features, there must be lots of people on this forum who would like to buy one and populate it themselves, or who would like to get your Gerber file to have their own boards manufactured.
Title: Re: $20 LCR ESR Transistor checker project
Post by: liquidair on February 02, 2021, 04:14:17 am
Just bought one of the kits along with some 0.1% resistors, new voltage reg and precision reference. I'm hoping to update it to Markus's latest version 1.42m, but I'm a simple creature and only know how to compile within Atmel Studio 7 or Visual Studio. I've tried nMake in VS console but get errors because of illegal characters '{' or something.  I've also tried going the "Create project from Makefile" route in AS7, but it keeps telling me "Failed to get info from Makefile. Did you select a valid Makefile?". Then of course I've tried to build the project outright in AS7 but the code depends so much on the Makefile I'm not sure how to decouple them. Could anyone help me get straightened out on a Windows machine?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 02, 2021, 11:23:42 am
DAIRVINE has posted a short guide for Atmel Studio 7 two pages back.
Title: Re: $20 LCR ESR Transistor checker project
Post by: liquidair on February 02, 2021, 03:01:58 pm
Thank you, madires! I tried DAIRVINE's method but it seems to have a problem with the Makefile on my machine for whatever reason. I just noticed there's more to it, so maybe there's something I missed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: liquidair on February 03, 2021, 02:27:12 am
So I read and re-read everything about compiling this with AS7, including adding the .elf extension to ${NAME} and nothing, still "Failed to get info from Makefile...". Anyone successfully compile 1.42m in AS7, or can tell me how to compile this with make on Windows? Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Ser9ei on February 04, 2021, 12:48:15 pm
liquidair,
In case the same issue with others projects, for example, k-firmware, please try reinstalling atmel studio with complete uninstallation of the previous version (check that directory with atmel studio will be removed after the “uninstallation operation”).
Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on February 05, 2021, 02:30:31 am
liquidair:
I was apparently able to compile 1.42m without errors.
I do not know if the code runs though as I am do not have hardware at this instant.

I will attach my output in case it may be of some use.

I also took a screenshot as I generated the project so I will attach that too.

Title: Re: $20 LCR ESR Transistor checker project
Post by: mrmox on February 05, 2021, 02:55:00 am
Can someone tell me if my LCR-T4 (now running K-Firmware mega328_T4_v2_st7565) should be able to
support the IR function if I attach a VS 1838 Infrared Receiver? (or is it TL1838?)

I think the IR is only in the M-Firmware, is this correct?

Thanks!

Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on February 05, 2021, 08:28:49 am
Anyone successfully compile 1.42m in AS7, or can tell me how to compile this with make on Windows? Thank you!

I have Windows 7 64 bit installed on my PC and I use Notepad Programmers from WinAVR to customize and compile code. For programming I use USBavr with AVRDUDESS.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on February 05, 2021, 09:31:23 am
Can someone tell me if my LCR-T4 (now running K-Firmware mega328_T4_v2_st7565) should be able to
support the IR function if I attach a VS 1838 Infrared Receiver? (or is it TL1838?)

In short: YES

Detailed: you must compile with SW_IR_RECEIVER enabled. Careful! Due to the 32k flash memory you will have to give up other options.
The IR receiver will be connected to the 3 test terminals according to the indication that is displayed on the screen.
You cannot use the HW_IR_RECEIVER hardware option due to the lack of free GPIO ports.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 05, 2021, 12:48:32 pm
Can someone tell me if my LCR-T4 (now running K-Firmware mega328_T4_v2_st7565) should be able to
support the IR function if I attach a VS 1838 Infrared Receiver? (or is it TL1838?)

I think the IR is only in the M-Firmware, is this correct?

Yep, the m-firmware supports standard IR receiver modules and about 20 protocols. You can either connect the IR receiver via the probes or a dedicated MCU pin (if there's one unused). The VS1838 seems to need an additional pull-up resistor for the data/out line (around 33k between data/out and Vcc).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alphonso on February 06, 2021, 01:27:50 am
Hi all,

Can anyone confirm that they can build the current trunk copy (113K) using Atmel Studio 7.0 in Windowsn10.
I can build 112k and Marcus 1.42 but 113K fails with message...

“recipe for target ‘directories’ failed”. At line 115 of the finish.mk file.

any help appreciated.

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: liquidair on February 06, 2021, 01:33:17 am
@Ser9ei & @mrmox, I did a complete uninstall and have the exact same problem as before. Is there a step I'm missing? mrmox, what version of VS7 are you on? And did you have to do anything special to the makefile and/or code to get it up and running or was it as simple as your image seemed to show. For kicks, I named the project JAYSMarkus like in your image but no dice. I might try the PN route, but I would prefer to stick with AS7 because its convenient to use with my JTAGICE3.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 06, 2021, 01:49:12 pm
Can anyone confirm that they can build the current trunk copy (113K) using Atmel Studio 7.0 in Windowsn10.
I can build 112k and Marcus 1.42 but 113K fails with message...

“recipe for target ‘directories’ failed”. At line 115 of the finish.mk file.

The related part in finish.mk is:
Code: [Select]
deleteobj:
        rm -rf $(OBJDIR)
# create directories
directories: deleteobj
        mkdir $(OBJDIR)
        mkdir $(DEPDIR)

To ignore errors from those shell commands you could prepend each command with a "-":
Code: [Select]
deleteobj:
        -rm -rf $(OBJDIR)
# create directories
directories: deleteobj
        -mkdir $(OBJDIR)
        -mkdir $(DEPDIR)

However, you might to have to create those directories manually (dep and Obj).
Title: Re: $20 LCR ESR Transistor checker project
Post by: almamater on February 06, 2021, 10:24:15 pm
 :-\ Today my 2016 EZM328 started showing this error message:

(https://i.postimg.cc/ctZ3t3VB/IMG-5113.jpg) (https://postimg.cc/ctZ3t3VB)
(https://i.postimg.cc/2LwZQ6YR/IMG-5114.jpg) (https://postimg.cc/2LwZQ6YR)

I've tried the SelfTest a few times but it always blocks when it asks for the 100nF capacitor..

With the multimeter's continuity test, the probe 1 is actually in contact with probe 3, is it normal?

I don't know what happened, I was testing a capacitor and started doing this, I don't know if it was completely discharged or not ... did i burned the 328??
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on February 06, 2021, 10:27:04 pm
Just bought one of the kits along with some 0.1% resistors, new voltage reg and precision reference. I'm hoping to update it to Markus's latest version 1.42m, but I'm a simple creature and only know how to compile within Atmel Studio 7 or Visual Studio. I've tried nMake in VS console but get errors because of illegal characters '{' or something.  I've also tried going the "Create project from Makefile" route in AS7, but it keeps telling me "Failed to get info from Makefile. Did you select a valid Makefile?". Then of course I've tried to build the project outright in AS7 but the code depends so much on the Makefile I'm not sure how to decouple them. Could anyone help me get straightened out on a Windows machine?

I never had a problem with the "Create project from Makefile", it just worked the first time I tried. I repeated this and it still works for me. So it can make a project. I did have a compile issue caused by a lack of a dep folder. The elf issue is only important if you want to simulate or debug. I know it sounds silly, but are you actually selecting the file called makefile, and have you extracted the files?
I did have a bit of trouble getting the LCD screen working, but finally found the correct settings for my LCD.

Also I am not sure that 0.1% resistors are going to help much, this is not a precision instrument, you are expecting too much.

I am now building the project straight in AS7. I initially had a series of compile errors, but resolved them all by moving the defines one at a time, (followed by a new compile) from the makefile into config.h. So this route is also possible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 06, 2021, 10:55:11 pm
I don't know what happened, I was testing a capacitor and started doing this, I don't know if it was completely discharged or not ... did i burned the 328??

Most likely. Anything with a voltage higher than 5V can damage the ATmega. You could replace the ATmega and program a new firmware, or buy a new clone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: liquidair on February 07, 2021, 01:08:18 am
I never had a problem with the "Create project from Makefile", it just worked the first time I tried. I repeated this and it still works for me. So it can make a project. I did have a compile issue caused by a lack of a dep folder. The elf issue is only important if you want to simulate or debug. I know it sounds silly, but are you actually selecting the file called makefile, and have you extracted the files?
I did have a bit of trouble getting the LCD screen working, but finally found the correct settings for my LCD.
I extracted what looks like all versions as .tgz files then extracted "ComponentTester-1.42m.tgz" to its own folder. Then ya, in that folder I use the file that says Makefile. What version of AS7 are you on? I'm using 7.0.2397 if that makes a difference. I'm hesitant to upgrade to the Microchip version. Maybe I'll try extracting again or try an earlier version, who knows maybe when I was first exploring I changed something in the Makefile that screws it up.

Also I am not sure that 0.1% resistors are going to help much, this is not a precision instrument, you are expecting too much.
Ah well, I found a Github page where someone did that to improve accuracy. Honestly, I doubt I will ever need this thing to be accurate, but that's kinda how I learn. Always trying to push things.
Title: Re: $20 LCR ESR Transistor checker project
Post by: liquidair on February 07, 2021, 01:39:27 am
So I just did the following:
1. Re-extracted v1.42m and tried that Makefile
2. Extracted v1.41m and tried that Makefile
3. Downgraded to AS7 7.0.1645 and tried both 1.41m and 1.42m Makefiles
4. Reinstalled AS7 7.0.1645 on my C: drive instead of my D: drive

Same thing each time "Failed to get info from Makefile. Did you select a valid makefile?"  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on February 07, 2021, 08:20:35 am
So I just did the following:
1. Re-extracted v1.42m and tried that Makefile
2. Extracted v1.41m and tried that Makefile
3. Downgraded to AS7 7.0.1645 and tried both 1.41m and 1.42m Makefiles
4. Reinstalled AS7 7.0.1645 on my C: drive instead of my D: drive

Same thing each time "Failed to get info from Makefile. Did you select a valid makefile?"  |O

I am using AS7 7.0.2389
I extracted v1.42m into a folder on my downloads. Then had to extract that file into a folder on downloads. You get a lot of .c and .h files and one named makefile. Do not try and modify this makefile or anything else in the download to start with.
I initially selected the wrong CPU, but that actually compiled and worked OK. Then repeated the process with the correct CPU to try and fix a problem. I have now moved all the defines from the makefile into config.h and now have a normal AS7 project. I am using the latest win10 64 bit on a HP 2570P laptop.

If you sort it out, please can you tell us how you fixed it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on February 07, 2021, 09:11:22 am
mrmox, if you were to put the ultimate transistor tester on the market, here are some cool features that it could include:
-- precision 5 volt regulator
-- high precision resistors
-- header pins for programming
-- a hardwired capacitor for convenient self adjustment
-- a relay to short connections whenever a measurement is not being made, preventing accidental tester destruction
-- an ATMega in a DIP socket so that it can be easily replaced if it ever gets damaged by misuse
-- clear markings to show the connections for frequency measurement, voltage measurement, and function generator
-- a 16MHz crystal
-- the latest M or K firmware
A typical user does not really need all of the above, but there is no reason that a kit or completed device could not have all of the above features.  I would like to buy one. 
Since an ideal tester is not available now, and since I don't quite know how to design my own board, I ordered an AY-AT type of kit from eBay, and precision parts from mouser.com.  Earlier posts from "blurpy" describe what to do, and I expect that it will all turn out quite well.   My tester will not have the relay or the self adjustment capacitor. 
For that matter, if you know how to design a board with all of those features, there must be lots of people on this forum who would like to buy one and populate it themselves, or who would like to get your Gerber file to have their own boards manufactured.

Bring out at least all unused pins to PTH pads, ideally all pins. Soldering onto fine SMD IC leads is challenging. Add a 0.1" matrix of holes/pads in unused board area.
Fit a self calibrate capacitor so that we can use the (variable frequency) internal RC oscillator.
Allow for use of debugwire(do not use the reset pin, a simple 10k to 5V is all that is required)
Put the 9V battery pads a bit further apart to avoid the risk of a stray wire shorting out the battery.

Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on February 07, 2021, 10:07:41 am
Has anyone tried using flyback to measure inductance?
Add a 1N4148 class diode with the anode to probe 1. Connect the cathode to a 100n X7R 50V capacitor, with the other capacitor terminal connected to 0V.
Then add a 1k resistor from the cathode of the diode/capacitor to PC3 (On a T4). The main purpose of the resistor is to limit current during discharge.
To start with, discharge the 100n. Then generate flyback pulses which charge the capacitor. For example probe 2 680R to 5V and probe 1 to 20R 0V, then set probe 2 to 20R 0V and three state probe 1, (in one action using DDRC).
This may allow slightly smaller inductors to be detected and higher resolution below 1000uH.
The 50V capacitor rating is necessary to keep the X7R within tolerance.
The cost of these components? Perhaps £0.03
Any thoughts?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alphonso on February 07, 2021, 11:02:11 pm
Thanks Madires,

Not making a lot of progress...

Can you advise what is required to build these these AVR projects using the current version of Windows 10.
I take it that WinAVR-2010010 is long dead, or,  can it be patched with the latest AVR toolchain.
WinAVR and Atmel Studio seem to conflict with each other.
Is it best to build these using avr-gcc from command line shell?

Regards
Alphonso
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 08, 2021, 07:02:44 am
Not making a lot of progress...
Can you advise what is required to build these these AVR projects using the current version of Windows 10.
I take it that WinAVR-2010010 is long dead, or,  can it be patched with the latest AVR toolchain.

Alphonso, liquidair - for successful work and compilation of fresh firmware in any edition of Windows (7-10) it is not at all necessary to install
the program is the monster ATMelStudio! I, like many others, have been using the compact and stable WinAVR2010010 for more than 5 years. For Windows 10, you must additionally replace 1 system library msys-1.0.dll. I wrote about this earlier on the forum for Dimidian
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3269218/#msg3269218 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3269218/#msg3269218)
In addition to what I wrote, using this version of AVR-GNUToolchain 3.4.4.24 allows you to get the most compact size of the firmware, which is especially important for the small amount of memory in ATMega328.  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 08, 2021, 01:00:38 pm
Has anyone tried using flyback to measure inductance?

Not yet.  Do you have any weblinks for more details?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Alphonso on February 08, 2021, 10:08:39 pm
Hi Indman

Many thanks, spent hours on this and all fixed in 5 minutes with your toolkit.
Could these be added to an updated copy of WinAVR-2010 on sourceforge?

Regards
Alphonso
Title: Re: $20 LCR ESR Transistor checker project
Post by: DAIRVINE on February 08, 2021, 10:30:22 pm
Has anyone tried using flyback to measure inductance?

Not yet.  Do you have any weblinks for more details?
Sorry, none at all. It just seemed like a good idea.
The basic advantage is that you build up the capacitor voltage over many cycles. Roughly, you  turn on the inductor at least long enough to build up the maximum current then switch off the current for at least long enough for the current to drop to 0, the inductor energy is then dumped into the capacitor. You then count the number of cycles to trigger the analog comparator, measure the exact voltage and some sums leads to inductance. You can verify that you have reached the maximum current because increasing the ON time does not increase the inductor energy. Even with a dead short you will build up voltage because of switching transients, so you get a zero offset.
Roughly, total energy = 0.5NLI^2, where N is the number of cycles. You can measure the charge vs Voltage for the capacitor+diode combination and so work out energy vs voltage and compensate non linear capacitors and diodes. Or use energy = (Vd* CV +0.5CV^2).

 So we get L = (Vd* CV +0.5CV^2)/(0.5NI^2). You do need to switch from charge to flyback in the same clock edge, which may need assembler.
Performance? I estimate around 10uH to 1000uH using the 680R, but with much better resolution than the RL method.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Twiggy on February 09, 2021, 07:35:45 pm
Hello everyone,

thank you for your work on this nice project.
I bought an Hiland m644 that did not power up properly from factory : screen would come on only when i pressed the rotary switch. (attached pic)

I thought that it might have been because the device came without any firmware, so thanks to your thread I built firmware 1.42m (attached .hex and .eep)

However even after flash (screen avrdude)the screen status is the same. I tried even with k firmware (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega644_hiland_m644/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega644_hiland_m644/))
but got a verification error : https://i.imgur.com/P0ZJOLE.png (https://i.imgur.com/P0ZJOLE.png)

Can you tell from avrdude log if flash had some error? Is there a way to have a command prompt on the device
to know if it is defective?

avrdude log : https://pastebin.com/9GRpmsBQ (https://pastebin.com/9GRpmsBQ)
settings used : https://i.imgur.com/V4MZRqi.png (https://i.imgur.com/V4MZRqi.png)

If you want I can give more details on firmware config.

thanks for reading me

Title: Re: $20 LCR ESR Transistor checker project
Post by: Ser9ei on February 09, 2021, 09:10:58 pm
Hi Twiggy!,
as I see in the log, you have an exception in during the firmware process:
  "avrdude.exe: warning: cannot set sck period. please check for usbasp firmware update."

Please try one these options (or perhaps all):
  - upgrade the firmware of usbasp (another programmator is nessasary)
    last firmware is here https://www.fischl.de/usbasp/ (https://www.fischl.de/usbasp/)
  - Install the driver for Usbasp with help the Zadig tool (https://zadig.akeo.ie/ (https://zadig.akeo.ie/)). Instructions - https://www.instructables.com/USBASP-Installation-in-Windows-10/ (https://www.instructables.com/USBASP-Installation-in-Windows-10/)

In the screenshot the avrdudess soft work in the "Verify" mode (Combobox "Verify" is checked).
I would like to hope, you don't forget to chose "Write" mode in during flashing process.

PS
And,
 - before start "flash" process, please check connection (and the "Bit clock(-b)") setting with the help "Detect" button.
 - set "Erase flash and EEPROM (-e)" checkbox in during the firmware process (Please be aware, it is just only for the "Write" process, for the "Read/Verify" process should be unchecked)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on February 09, 2021, 09:47:10 pm
Hello everyone,

thank you for your work on this nice project.
I bought an Hiland m644 that did not power up properly from factory : screen would come on only when i pressed the rotary switch. (attached pic)

I thought that it might have been because the device came without any firmware, so thanks to your thread I built firmware 1.42m (attached .hex and .eep)

However even after flash (screen avrdude)the screen status is the same. I tried even with k firmware (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega644_hiland_m644/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega644_hiland_m644/))
but got a verification error : https://i.imgur.com/P0ZJOLE.png (https://i.imgur.com/P0ZJOLE.png)

Can you tell from avrdude log if flash had some error? Is there a way to have a command prompt on the device
to know if it is defective?

avrdude log : https://pastebin.com/9GRpmsBQ (https://pastebin.com/9GRpmsBQ)
settings used : https://i.imgur.com/V4MZRqi.png (https://i.imgur.com/V4MZRqi.png)

If you want I can give more details on firmware config.

thanks for reading me

Hello!

From what I saw in the pictures, you have problems with lockbit. The MCU you want to program is locked, see the attached images.
That's why the flash check gives an error. LB should have the value 0xFF.
According to the manufacturer's documentation "The Lock bits can only be
erased to “1” with the Chip Erase command. "

You must enter command com and give the command:

avrdude  -c usbasp -p m664p -e

Then read fuses & lock bits with AVRDUDESS.
Everything should be 0xFF. Write the desired values: L = 0xFF, H = 0xD9, E = 0xFC, LB remains 0xFF.

Only now can you load the desired firmware.

Good luck with that!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Twiggy on February 09, 2021, 10:14:38 pm
[...]


Hello Ser9ei, thanks for your reply! It's weird to me that this is the problem because it's displayed as a warning, not an error, and the write process continues and even verifies at the end. So it must somehow be able to find a SCK frequency thats accepted.

- before start "flash" process, please check connection (and the "Bit clock(-b)") setting with the help "Detect" button.
When I click detect, it says :
Code: [Select]
>>>: avrdude -u -c usbasp -B 0.5 -v -p m8
Detected 1e960a = ATmega644P
but does not set the baud rate (-b) nor Bit clock (-B). I left it by default at 1.5 MHz. I don't know what value to use.

I would like to hope, you don't forget to chose "Write" mode in during flashing process.
I did not do that mistake  :scared: . I think if I made a mistake, avrdude log would not show the writing process.

Please try one these options (or perhaps all):
  - upgrade the firmware of usbasp (another programmator is nessasary)
    last firmware is here https://www.fischl.de/usbasp/ (https://www.fischl.de/usbasp/)
  - Install the driver for Usbasp with help the Zadig tool (https://zadig.akeo.ie/ (https://zadig.akeo.ie/)). Instructions - https://www.instructables.com/USBASP-Installation-in-Windows-10/ (https://www.instructables.com/USBASP-Installation-in-Windows-10/)
Aww, it took long enough for the first one to arrive  |O Are you absolutely sure this is the issue despite avrdude process saying it succeeds in flashing & verifying data?

I did not have any issues installing the driver on my PC as I do not use windows 10 :P. I used windows 7 driver from https://eecs.oregonstate.edu/education/inventory_datasheets/P1438967372-1443308202.pdf (https://eecs.oregonstate.edu/education/inventory_datasheets/P1438967372-1443308202.pdf) section 4.1.1 and it installed well. According to what you said, the issue would not be the pc driver but the firmware itself, right? So I don't need to change that driver.


From what I saw in the pictures, you have problems with lockbit. The MCU you want to program is locked, see the attached images.
That's why the flash check gives an error. LB should have the value 0xFF.
According to the manufacturer's documentation "The Lock bits can only be
erased to “1” with the Chip Erase command. "

You must enter command com and give the command:

avrdude  -c usbasp -p m664p -e

Then read fuses & lock bits with AVRDUDESS.
Everything should be 0xFF. Write the desired values: L = 0xFF, H = 0xD9, E = 0xFC, LB remains 0xFF.

Only now can you load the desired firmware.

Good luck with that!

Hello :)
Where did you go to make those screenshots? I went to : https://www.engbedded.com/fusecalc?P=ATmega644P (https://www.engbedded.com/fusecalc?P=ATmega644P) but it does not say anything for the lock bits.
Also according to my pastebin the flash check does not fail - am I missing something?

I did the command you hinted : https://i.imgur.com/CRxCLr8.png (https://i.imgur.com/CRxCLr8.png) and it directly sets the values you told me.

When I ask to write lock bit, it fails : https://pastebin.com/UwS2DfC1 (https://pastebin.com/UwS2DfC1)
avrdudess was like this : https://i.imgur.com/D78cvy2.png (https://i.imgur.com/D78cvy2.png) do I need to check "Set lock" or do something else?

thanks

Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on February 10, 2021, 10:17:24 am

Hello :)
Where did you go to make those screenshots? I went to : https://www.engbedded.com/fusecalc?P=ATmega644P (https://www.engbedded.com/fusecalc?P=ATmega644P) but it does not say anything for the lock bits.
Also according to my pastebin the flash check does not fail - am I missing something?


I did the command you hinted and it directly sets the values you told me.

When I ask to write lock bit, it fails
avrdudess was like this : ...  do I need to check "Set lock" or do something else?

thanks

OK. Let's take them one at a time:

1. The USBasp firmware warning can be easily ignored if you do not program any ATtiny series MCUs.

2. in the case of flash memory a cell is deleted (empty) if it is written with logic 1, ie the byte has the value 0xFF. It is normal to give some errors if, instead of erase, you try to write the value 0xFF.

3. try this fusebit computer too: https://eleccelerator.com/fusecalc/fusecalc.php?chip=atmega644p (https://eleccelerator.com/fusecalc/fusecalc.php?chip=atmega644p)
it is more complete.

4. let's make a difference: avrdude.exe is a program that can be used in the com command terminal, while AVRDUDESS is a graphical interface (GUI) for avrdude.exe.

5. to know the status of the fusebits, in AVRDUDE press the read buttons. If the result is L = 0xFF, H = 0xD9, E = 0xFC, LB = 0xFF then you should have no more difficulties in programming the ATmega644 MCU.

If you still have questions, tell me and, if I know, I'll help you.

A good day.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Twiggy on February 10, 2021, 06:44:04 pm

1. The USBasp firmware warning can be easily ignored if you do not program any ATtiny series MCUs.
2. in the case of flash memory a cell is deleted (empty) if it is written with logic 1, ie the byte has the value 0xFF. It is normal to give some errors if, instead of erase, you try to write the value 0xFF.
3. try this fusebit computer too: https://eleccelerator.com/fusecalc/fusecalc.php?chip=atmega644p (https://eleccelerator.com/fusecalc/fusecalc.php?chip=atmega644p)
it is more complete.
4. let's make a difference: avrdude.exe is a program that can be used in the com command terminal, while AVRDUDESS is a graphical interface (GUI) for avrdude.exe.
5. to know the status of the fusebits, in AVRDUDE press the read buttons. If the result is L = 0xFF, H = 0xD9, E = 0xFC, LB = 0xFF then you should have no more difficulties in programming the ATmega644 MCU.


1. Thanks thats good to know :)
2. Not sure what you mean. I do avrdude command like you said :
Code: [Select]
PS D:\tools\AVRDUDESS-2.13-portable> .\avrdude.exe -c usbasp -p m644p -e
avrdude.exe: warning: cannot set sck period. please check for usbasp firmware update.
avrdude.exe: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.02s
avrdude.exe: Device signature = 0x1e960a (probably m644p)
avrdude.exe: erasing chip
avrdude.exe: warning: cannot set sck period. please check for usbasp firmware update.
avrdude.exe: safemode: Fuses OK (E:FC, H:DF, L:FF)
avrdude.exe done.  Thank you.

Then i read lock bits: :

Code: [Select]
> .\avrdude.exe -c usbasp -p m644p -U lock:r:-:h
avrdude.exe: warning: cannot set sck period. please check for usbasp firmware update.
avrdude.exe: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.02s
avrdude.exe: Device signature = 0x1e960a (probably m644p)
avrdude.exe: reading lock memory:
Reading | ################################################## | 100% 0.01s
avrdude.exe: writing output file "<stdout>"
0x3f

avrdude.exe: safemode: Fuses OK (E:FC, H:D9, L:FF)

avrdude.exe done.  Thank you.
>



and when I write 0XFF :
Code: [Select]
PS D:\Documents de Anis\Hobbies\Hiland m644\tools\AVRDUDESS-2.13-portable> .\avrdude.exe -c usbasp -p m644p -v -v -U lock:w:0xFF:m

[...]

avrdude.exe: Device signature = 0x1e960a (probably m644p)
avrdude.exe: safemode: hfuse reads as D9
avrdude.exe: safemode: efuse reads as FC
avrdude.exe: reading input file "0xFF"
avrdude.exe: writing lock (1 bytes):

Writing |                                                    | 0% 0.00s ***failed;
Writing | ################################################## | 100% 0.06s

avrdude.exe: 1 bytes of lock written
avrdude.exe: verifying lock memory against 0xFF:
avrdude.exe: load data lock data from input file 0xFF:
avrdude.exe: input file 0xFF contains 1 bytes
avrdude.exe: reading on-chip lock data:

Reading | ################################################## | 100% 0.01s

avrdude.exe: verifying ...
avrdude.exe: verification error, first mismatch at byte 0x0000
             0x3f != 0xff
avrdude.exe: verification error; content mismatch

avrdude.exe: safemode: hfuse reads as D9
avrdude.exe: safemode: efuse reads as FC
avrdude.exe: safemode: Fuses OK (E:FC, H:D9, L:FF)

avrdude.exe done.  Thank you.

We can see in log that the write operation fails. Why?

Besides, thanks for the fuse calculator =)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Ser9ei on February 11, 2021, 03:10:51 am
We can see in log that the write operation fails. Why?
Quote from: Atmel DataSheet
The LockBits can only be erased to “1” with the Chip Erase command.
The Chip Erase will erase the Flash and EEPROM memories plus Lock Bits. The Lock Bits are not reset until the Program memory has been completely erased. The Fuse Bits are not changed. A Chip Erase must be performedbefore the Flash and/or the EEPROM are reprogrammed.

- set "Erase flash and EEPROM (-e)" checkbox in during the firmware process (Please be aware, it is just only for the "Write" process, for the "Read/Verify" process should be unchecked)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Twiggy on February 11, 2021, 10:51:57 am
[...]

I read this already. I made a mistake formatting my previous post; I did chip erase (-e) as Dumidan said, read lock bit and got 0x3f, and tried to write lock bit, which failed as you explained.

Chip erase did not put lock bit to 0xFF.

Look here https://yadi.sk/d/IUL_bjs0K3A6OA (https://yadi.sk/d/IUL_bjs0K3A6OA)
I will try your fuse bits tonight. I would like to see the avrdude command that your GUI executes when flashing please.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 11, 2021, 11:23:59 am
Everything should be 0xFF. Write the desired values: L = 0xFF, H = 0xD9, E = 0xFC, LB remains 0xFF.

The recommended setting of the low fuse for the Hiland M644 (ATmega 644, 8MHz) is 0xf7.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Twiggy on February 11, 2021, 11:57:26 pm
What I compiled was wrong. used Yuriy_K's files (k firmware) with L = 0xF7, H = 0xD9, E = 0xFC and the menu came on. Device is very slow, takes 2s to scroll 1 item in the menu, things such as "exit voltage mode" took 10s of press to finish instead of 4, etc. It said battery 4.5V empty but it reads 7.6V on voltmeter.
Somehow I couldn't get the device to start after  I unplugged the programmer. screen would light up when i press the button but no matter how long i press the menu wouldnt show.
If I plug the programmer screen comes and stays on but menu does not show.
Seems like I don't know how to use the thing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Twiggy on February 13, 2021, 04:35:39 pm
Ok my 9V battery what was caused the device to not start, despite reading >7V. I wouldn't expect a device with a faulty battery to have the screen come on at all when pressing the start button..

Firmware from SVN trunk is ok now. Yuriy, your 8MHz firmware works as well, thanks.
As I bought this device for repair purposes to find dead components, I don't think I'll mind measurements errors.

What I compiled can make the device boot (as the red led light comes on) however the screen isn't driven properly (blank).
My screen is JLX12864G-378 Ver2.1 so i edited only st7565R section


Here are the files I modified. I tried to use section 7.07 of the manual. Please tell me what I did wrong.
https://www.diffchecker.com/bVoA3MMh (https://www.diffchecker.com/bVoA3MMh)
https://www.diffchecker.com/5dVZn1Jq (https://www.diffchecker.com/5dVZn1Jq)
https://www.diffchecker.com/87LiCWo6 (https://www.diffchecker.com/87LiCWo6)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Twiggy on February 16, 2021, 11:43:47 pm

What I compiled can make the device boot (as the red led light comes on) however the screen isn't driven properly (blank).
My screen is JLX12864G-378 Ver2.1 so i edited only st7565R section
Having a finely tuned version with a color display, it took me several hours to create a working version for you. Firmware for quartz 8 MHz. All corrected files are in the archive, and examples of measurements for monochrome and color displays.
All the best...
https://disk.yandex.ru/d/KOJ56yV7Rxo28g (https://disk.yandex.ru/d/KOJ56yV7Rxo28g)
Thank you so much!

here are diffs of what you changed, in case it helps someone else..
https://www.diffchecker.com/V0LPrhN0 (https://www.diffchecker.com/V0LPrhN0)
https://www.diffchecker.com/ieuImOYb (https://www.diffchecker.com/ieuImOYb)
https://www.diffchecker.com/KGUSgUMW (https://www.diffchecker.com/KGUSgUMW)
https://www.diffchecker.com/PX8fjGOG (https://www.diffchecker.com/PX8fjGOG)
https://www.diffchecker.com/gppBmW9E (https://www.diffchecker.com/gppBmW9E)

I couldnt compile your files as is though, I took all your files but config.h and it compiled but with your config.h i got :
Code: [Select]
tools_signal.c: In function 'FrequencyCounter':
tools_signal.c:1779: warning: 'Index' may be used uninitialized in this function
avr-gcc -mmcu=atmega644 -Wall -I. -Ibitmaps -DF_CPU=8000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -mcall-prologues -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT tools_LC_Meter.o -MF dep/tools_LC_Meter.o.d -c tools_LC_Meter.c
tools_LC_Meter.c: In function 'LC_Calc_C':
tools_LC_Meter.c:363: error: fixed-point types not supported for this target
tools_LC_Meter.c:364: error: fixed-point types not supported for this target
tools_LC_Meter.c:377: error: fixed-point types not supported for this target
tools_LC_Meter.c:378: error: fixed-point types not supported for this target
tools_LC_Meter.c:380: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:380: error: invalid operands to binary - (have '<unnamed-fixed:64>' and 'int')
tools_LC_Meter.c:387: error: fixed-point types not supported for this target
tools_LC_Meter.c:390: warning: implicit declaration of function 'bitsulk'
tools_LC_Meter.c:390: error: '__ULACCUM_FBIT__' undeclared (first use in this function)
tools_LC_Meter.c:390: error: (Each undeclared identifier is reported only once
tools_LC_Meter.c:390: error: for each function it appears in.)
tools_LC_Meter.c:396: error: fixed-point types not supported for this target
tools_LC_Meter.c:402: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:402: error: invalid operands to binary * (have '<unnamed-fixed:64>' and 'int')
tools_LC_Meter.c: In function 'LC_Calc_L':
tools_LC_Meter.c:426: error: fixed-point types not supported for this target
tools_LC_Meter.c:427: error: fixed-point types not supported for this target
tools_LC_Meter.c:443: error: fixed-point types not supported for this target
tools_LC_Meter.c:444: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:444: error: invalid operands to binary / (have '<unnamed-fixed:64>' and 'int')
tools_LC_Meter.c:446: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:446: error: invalid operands to binary / (have 'int' and '<unnamed-fixed:64>')
tools_LC_Meter.c:449: error: fixed-point types not supported for this target
tools_LC_Meter.c:450: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:450: error: invalid operands to binary / (have '<unnamed-fixed:64>' and 'int')
tools_LC_Meter.c:452: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:452: error: invalid operands to binary / (have 'int' and '<unnamed-fixed:64>')
tools_LC_Meter.c:459: error: fixed-point types not supported for this target
tools_LC_Meter.c:460: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:460: error: invalid operands to binary * (have '<unnamed-fixed:64>' and 'uint32_t')
tools_LC_Meter.c:461: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:461: error: invalid operands to binary / (have '<unnamed-fixed:64>' and 'long int')
tools_LC_Meter.c:462: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:462: error: invalid operands to binary / (have 'int' and '<unnamed-fixed:64>')
tools_LC_Meter.c:463: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:463: error: invalid operands to binary * (have '<unnamed-fixed:64>' and 'long int')
tools_LC_Meter.c:472: sorry, unimplemented: GCC cannot support operators with integer types and fixed-point types that have too many integral and fractional bits together
tools_LC_Meter.c:472: error: invalid operands to binary * (have '<unnamed-fixed:64>' and 'int')
tools_LC_Meter.c:482: error: '__ULACCUM_FBIT__' undeclared (first use in this function)
make.exe: *** [tools_LC_Meter.o] Error 1


I found that uncommenting #define HW_LC_METER produced this error. is that related to winavr toolchain somehow?

Quote
- Added LC meter hardware option (HW_LC_METER). It’s based on a simple LC oscillator
circuit, similar to some inexensive LC meter kits.
please explain this part of the manual. if it's hardware related how comes yuriy's uses it and it works on my board, but when I don't use it it still works on my board?
Title: Re: $20 LCR ESR Transistor checker project
Post by: v81 on February 17, 2021, 07:00:25 am
I've hit a roadblock with my tester, sourced from AliExpress.
Keen to swap firmware on it, but have never compiled or flashed anything outside the Arduino IDE before.

I do have an Atmel AVRISP MkII and a separate board with an ICSP header, is that all i need re hardware?
I have the code "ComponentTester-1.42m" and have made some changes to the make file, specifically the 20MHz xtal and some onewire stuff (it does currently read a DS18B20, and i'd like to keep that).
I've hit a roadblock as to what display i have.
It's colour, has 8 pins CD4050 chip on it.
Pic here..
[attach=1]

Any assistance appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Steve3103 on February 17, 2021, 09:44:40 am
Gentlemen, this is my first post and I would firstly like to give many thanks for the help and support you give to those with less knowledge than yourselves.
I have two AY-AT testers and, thanks to the advice given here and many, many hours of reading through the previous posts, they are both working.  The rotary encoder seems to work in reverse on one of them (turn clockwise instead of anti-clockwise) but that does not appear to be a problem.  The measurements are reasonably close but I don’t expect it to be a precision tester just a tool to help me identify faulty components.   My problem is that one of the screens was broken when it was supplied – unfortunately it was some months before I built that tester and it is too late to return the faulty part.  I have purchased a new display 1.8” ST7735 SPI but I notice that the pinouts are not the same as detailed in this forum – picture attached.  I have tried cross wiring to compensate – pin 1 of the new tester to pin 8 of the socket, 2 to 7, 3 to 5, 4 to 4, 5 to 2, 6 to 3, 7 to 6 and 8 to 1 – but only the backlight comes on and only when the encoder is pressed.   Have I wasted my money and need to buy another screen or do you have any ideas that might help?
Thank you for reading.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 17, 2021, 10:23:54 am
I have two AY-AT testers and, thanks to the advice given here and many, many hours of reading through the previous posts, they are both working.    I have purchased a new display 1.8” ST7735 SPI but I notice that the pinouts are not the same as detailed in this forum – picture attached.
3 questions for you:
1. Why are you sure that the tester with a broken display is working?
2. Have you switched a working display from one device to another?
3. Are you sure the new display has an ST7735 controller?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Steve3103 on February 17, 2021, 11:10:59 am
Hello Indman,
yes, I tried the screen from the working tester.

Hello Yuriy_K
thank you - I will reprogram the chip with these new files and report back.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Steve3103 on February 17, 2021, 11:36:09 am
Indman - sorry, I forgot to answer your final question - the screen indicates ST7735 on the reverse - photo attached.
Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2021, 11:37:01 am
I found that uncommenting #define HW_LC_METER produced this error. is that related to winavr toolchain somehow?

That switch is meant for the LC meter hardware option which is an additional circuit. Simply keep it commented out if you don't have that hardware option (commented out by default). The compiler errors are caused by the avr-gcc version you run, it doesn't support fixed-point variable types. Since fixed-point types are only used for the LC meter hardware option don't worry about that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2021, 11:52:39 am
Indman - sorry, I forgot to answer your final question - the screen indicates ST7735 on the reverse - photo attached.

That display doesn't seem to have a level shifter, only a 3.3V LDO. Does the old display have a level shifter (e.g. 74HC4050)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Steve3103 on February 17, 2021, 12:07:01 pm
Hello Madires,  thank you for becoming involved.  I have attached a copy of the screen as, even with a magnifying glass, I can not read what is printed on the chip.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2021, 12:34:42 pm
It's an HEF4050. If the LCD of the new module has the same flat-flex as the broken one you could use the new LCD with the old PCB to retain the level shifter (and the pinout). Otherwise you'd need to add a level shifter to the new display. The ST7735 is a 3.3V controller while the ATmega runs at 5V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Steve3103 on February 17, 2021, 12:39:11 pm
I will investigate and see what I can do.
Many thanks for your advice - much appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: drussell on February 17, 2021, 02:43:33 pm
Hi, guys....

I'd like to get a couple of these tester-doodles but there is such a ridiculous number of variants, I don't know which one to buy (or more correctly I suppose, if there are any specific models that I should avoid.)

Specifically, is there anything wrong with this particular variant, I'm thinking of getting a couple of these:
(https://i.imgur.com/1LRqU15.png)

This variant comes with a basic rechargeable Li-ion pack built in and with the current quantity discount, promotional codes, coupons and free shipping, I can get two of them for under $45 CAD total for the pair. 

That seems like a reasonable deal unless there is something spectacularly wrong with this model.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2021, 03:05:14 pm
TC-1's XXL drawback is U4, an additional MCU to control power and the test button. The other family members share the same design. If you like to run one of the two OSHW firmwares you need either to reprogram U4 or to replace it with a two-transistor circuit which also reduces the quiesent current dramatically. Some units come with cheap components in the power supply circuitry (shorted MLCCs, underrated Schottky diode or MLCCs for the 50V boost converter).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Twiggy on February 17, 2021, 08:52:57 pm
I found that uncommenting #define HW_LC_METER produced this error. is that related to winavr toolchain somehow?

That switch is meant for the LC meter hardware option which is an additional circuit. Simply keep it commented out if you don't have that hardware option (commented out by default). The compiler errors are caused by the avr-gcc version you run, it doesn't support fixed-point variable types. Since fixed-point types are only used for the LC meter hardware option don't worry about that.

Okay that about clears it for me, thank you for your firmware, your support, and also thanks again yuriy :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: v81 on February 17, 2021, 11:35:49 pm
I've hit a roadblock as to what display i have.
It's colour, has 8 pins CD4050 chip on it.
ST7735 - You must set this display to config_328.h...

Thanks for that.
Have done this by removing the //#if 0 and //#endif for the section ..
Code: [Select]
/*
 *  ST7735
 *  - 4 wire SPI interface using bit-bang SPI
 */
Compiles and runs ok, but i get a grey screen when i hit the encoder button.
Any ideas?

Also is there any way to tell what display it is, like a guide or tell tale signs, or you just know it by sight or memory?

Out of curiosity i flashed the hex from the archive you linked from the Russian forum above and that worked OK, but the display was upside down.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 18, 2021, 05:53:21 am
I have the code "ComponentTester-1.42m" and have made some changes to the make file, specifically the 20MHz xtal and some onewire stuff (it does currently read a DS18B20, and i'd like to keep that).
I've hit a roadblock as to what display i have.
It's colour, has 8 pins CD4050 chip on it.

There is no need  invent anything in a new way!
You have a standard kit for the AY-AT clone
Ready-made firmware for your clone can be applied directly from the k-firmware distribution
https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk/mega328_color_kit
AY-AT clone configuration settings for m-firmware can be viewed in the Clone file, which was kindly provided by madires
Ready-made k-firmware and m-firmware in English can be freely downloaded from my resource here
https://yadi.sk/d/yW8xa5NJgUo5z
For the AY-AT clone, you need to select the "M328Kit + TFT/Firmware/Markus Reschke/English" folder for downloading
Title: Re: $20 LCR ESR Transistor checker project
Post by: v81 on February 18, 2021, 07:58:04 am
Out of curiosity i flashed the hex from the archive you linked from the Russian forum above and that worked OK, but the display was upside down.
Show the photo as inverted, it can be easily removed ...
This will probably be the solution to your problem ...
https://disk.yandex.ru/d/39xY4idSzvHvaw

This did not work at all.
Only a grey screen when the encoder button is held down.

The firmware you linked to in this post did work, but with upside down display.

Also i have modified the crystal to 20MHz
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 18, 2021, 08:14:32 am
Also i have modified the crystal to 20MHz
I suggest you return to 16MHz crystal. 20MHz does not provide any particular performance advantage, but it significantly reduces the stability work of the Chinese processor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: v81 on February 18, 2021, 08:37:29 am
Also i have modified the crystal to 20MHz
I suggest you return to 16MHz crystal. 20MHz does not provide any particular performance advantage, but it significantly reduces the stability work of the Chinese processor.
The original was 8MHz, and the interface was slow and clunky.
I might be better off switching to a unit with a mono display for better features and performance.
Would love to have the menu that was in the firmware of my original, supported extras like reading DS18B20 etc..

This did not work at all.
Only a grey screen when the encoder button is held down.

Also i have modified the crystal to 20MHz
I confirm the messages of indman, but for verification, here is the firmware for 20 MHz.
https://disk.yandex.ru/d/JDI0RR_KVcx1Xg

Thanks, I'll try this one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: v81 on February 18, 2021, 08:50:19 am
There is no need  invent anything in a new way!
You have a standard kit for the AY-AT clone
Ready-made firmware for your clone can be applied directly from the k-firmware distribution
https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk/mega328_color_kit
AY-AT clone configuration settings for m-firmware can be viewed in the Clone file, which was kindly provided by madires
Ready-made k-firmware and m-firmware in English can be freely downloaded from my resource here
https://yadi.sk/d/yW8xa5NJgUo5z
For the AY-AT clone, you need to select the "M328Kit + TFT/Firmware/Markus Reschke/English" folder for downloading

I'm actually intending to do some modifications, so i do need to re-compile the code.
I have already swapped out the crystal for a 20MHz unit, and i have a precision 2.5v reference ready to try.
In addition to that I'd like to incorporate any improvements recent firmware has bought.
Finally, I'm not super familiar with working outside the arduino IDE, so it's also a learning experience to learn to select the correct options and compile the code.
Flashing firmware intended for a clone which was originally 8MHz, but which has been modified to 20MHz will affect the test results i think.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 18, 2021, 09:10:11 am
@v81 The folder "M328Kit + TFT / Firmware / Markus Reschke / English" contains ready-made firmware for 3 different clock frequencies 8MHz, 16MHz and 20MHz. Look carefully! |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: v81 on February 18, 2021, 09:31:24 am
v81 The folder "M328Kit + TFT / Firmware / Markus Reschke / English" contains ready-made firmware for 3 different clock frequencies 8MHz, 16MHz and 20MHz. Look carefully! |O

Tried this previously and it didn't work, but have since tried it again and it does work.
Have flashed it across 2 different MCUs and it consistently fails on one of them... possible counterfeit or dud???
I know one of them came with the component tester and the other is sourced via Element14 in Australia.

So now i have a couple of firmwares working on 20MHz

The ready made firmware above does not seem to have a menu or any way to interact with the rotary encoder, just seems to repeat the test over and over.
Is there a way to add OneWire functionality to it?

To you and Yuriy_K - i appreciate both your help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 18, 2021, 09:55:58 am
The ready made firmware above does not seem to have a menu or any way to interact with the rotary encoder, just seems to repeat the test over and over.
Read carefully the Tester Control Readme by madires. This must be done in the first place, if you want to use all the capabilities of the device correctly. Tester management on m-firmware differs from the work of k-firmware. See https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3260672/#msg3260672 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3260672/#msg3260672)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hamlet600 on February 18, 2021, 12:58:41 pm
where can i calibrate zener reading in m-firmware?
thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 18, 2021, 03:15:51 pm
There's no need for an additional adjustment for the Zener voltage, because the normal adjustment takes care about the reference voltages anyway. However, the resistor values of the voltage divider for the Zener voltage could be off by some degree. There's also one clone which doesn't use the standard 10:1 divider. BTW, the next version of the m-firmware will allow to specify resistor values for a custom voltage divider.
Title: Re: $20 LCR ESR Transistor checker project
Post by: drussell on February 18, 2021, 07:03:25 pm
TC-1's XXL drawback is U4, an additional MCU to control power and the test button. The other family members share the same design. If you like to run one of the two OSHW firmwares you need either to reprogram U4 or to replace it with a two-transistor circuit which also reduces the quiesent current dramatically. Some units come with cheap components in the power supply circuitry (shorted MLCCs, underrated Schottky diode or MLCCs for the 50V boost converter).

Ahh...  Thank you.

That gave me enough to search for everything I needed to know which was posted in various places earlier in this thread.  I see it is easy enough to modify that U4 circuitry to be generic (and essentially simpler and better!) if and when I move up to the generic open source firmware.

Thank you guys for all your hard work with regard to these units!!   :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: hamlet600 on February 18, 2021, 07:30:49 pm
is there any option in m-firmware which generate predetermined pulse duration(for example 100ms)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 18, 2021, 08:32:51 pm
Not for a single pulse.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hamlet600 on February 19, 2021, 02:08:53 pm
Not for a single pulse.

very usefull feature if you consider in next version update!
Title: Re: $20 LCR ESR Transistor checker project
Post by: XantheFIN on February 23, 2021, 09:58:54 am
I have read from here too that LCR meter can be used to measure Battery impedance if added example DC blocking cap.

I have here mega328_T4_v2_st7565 firmware installed at moment on mine cheap "LCR" meter and it shows resistance with that config plus capacitor but i am not sure what exactly it is and so i want check is it false reading and if its impossible.

I would be in time to check what are bad cells on my laptop battery.


If asked earlier i apologise.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 23, 2021, 11:42:51 am
The Transistortester's ESR measurement can't measure battery impedance because it doesn't create an AC test signal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: XantheFIN on February 23, 2021, 12:14:10 pm
Thanks. Makes sense as I didn't check that yet. Will go resistance measurement with arduino.

Edit. About the tester:

I downloaded and put software/firmware from here: https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk/mega328_T4_v2_st7565

i trying to calibrate as it keeps nagging about it. It goes in self test mode but i don't get isolate probe message. My point to get that extra menu too but it does not get there as well.


Edit2: It was about my backlight led dying, added another led instead of bridge and works now.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 24, 2021, 01:35:33 pm
Dumidan
for Windows optimal https://drive.google.com/file/d/1DL5--2RUFIncdO8PmW87Bz9DzwPw5ms0/view?usp=sharing (https://drive.google.com/file/d/1DL5--2RUFIncdO8PmW87Bz9DzwPw5ms0/view?usp=sharing)

I have updated the instructions for easy and quick installation of WinAVR and compilation of the firmware for my tester. The manual now contains an updated link to the GItHub with the k-firmware and m-firmware distributions. Thanks to de_light for help in editing the description in English! Good luck with your use!  :)
https://drive.google.com/file/d/1-IJA8uTcsCA_6SYHEuMydjfS2vNgmwdH/view?usp=sharing
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 01, 2021, 07:46:19 pm
It seems that mikrocontroller.net is migrating from SVN to git. So the new main repository is https://github.com/Mikrocontroller-net/transistortester which makes downloading much simpler.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Shannon on March 02, 2021, 01:02:10 am
Jumping into this thread
You may be interested in this project, the performance of the LCR meter is awesome ;)

https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/msg3473886/#msg3473886 (https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/msg3473886/#msg3473886)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2021, 09:49:51 am
Unfortunately not an OSHW project. Kickstarter planned, price around US$ 100.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on March 03, 2021, 01:34:13 am
It seems that mikrocontroller.net is migrating from SVN to git. So the new main repository is https://github.com/Mikrocontroller-net/transistortester (https://github.com/Mikrocontroller-net/transistortester) which makes downloading much simpler.
I have a self made tester with m328 and ST7108 display (k-firmware). So, I checked the new repository link and saw that there are some updated files in 'transistortester/Software/trunk/' folder. I decided to download the trunk and compile a new firmware. I know there are ready compiled files but I prefer a different font and options. So, I prepared my makefile and executed the make.exe. I got this error:

Code: [Select]
The system cannot find the path specified.
rm -rf ../Obj/mega328_st7108
process_begin: CreateProcess(NULL, rm -rf ../Obj/mega328_st7108, ...) failed.
make (e=2): The system cannot find the file specified.
make: *** [../finish.mk:112: deleteobj] Error 2

The 'Obj' folder have 3 different folder for ST7565 display and a 'TransistorTester' folder. So, I created the 'mega328_st7108' folder under 'Obj'. And same error again. I searched this thread and found your answer about modifying finish.mk file:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3450818/#msg3450818 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3450818/#msg3450818)
So, I added "-" before those commands. Then those errors ignored. But got this error:

Code: [Select]
../lcd_hw_4_bit.S:8:0: fatal error: opening dependency file ../Obj/mega328_st7108/dep/lcd_hw_4_bit.o.d: No such file or directory

compilation terminated.
make: *** [../finish.mk:14: ../Obj/mega328_st7108/lcd_hw_4_bit.o] Error 1

Then I copied all the files under 'Obj/TransistorTester/dep' to the 'Obj/mega328_st7108/dep'. And finally it's compiled:

Code: [Select]
Program:   30304 bytes (92.5% Full)
(.text + .data + .bootloader)

Data:        190 bytes (9.3% Full)
(.data + .bss + .noinit)

EEPROM:      841 bytes (82.1% Full)
(.eeprom)

Did I get the correct firmware?

ps: I find the k-firmware modifications confusing, there is no version number change or something like that, right? Is there a way to determine the current state of the firmware?

Thanks for reading.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 03, 2021, 10:00:26 am
When the firmware compiles without errors it should be fine. The version in the 'trunk' directory is the current k-firmware under development, similar to a beta version. With git the changes are referenced by the commit IDs. The finished versions are in 'tags'.
Title: Re: $20 LCR ESR Transistor checker project
Post by: b0hoon on March 06, 2021, 01:49:45 pm
Hi,

I don't know if it's right thread, but anyway to the point... I bought lately GM328A tester from aliexpress, for something like ten bucks with shipping. It came of course with the old version 1.12k of firmware, so i wanted to upgrade it with 1.42m. It had a strange lcd module, with additional unknown chip between buffer and controller, white silicone around the controller, module was mounted on pins on the left side (not on screws). On picture "LCD modules.jpg", on left side is my lcd module from the DIY GM328 red kit.

It turned out that after flashing atmega, this lcd just doesn't work, no matter what, but both lcd modules, this one and one from GM328 "red kit" worked on version 1.13k. I spent almost a week to get this thing working, and here is what i've finally done:

1) no image, garbage on the screen -  generally this module behaves like ST7735, but needs CS switching between sending bytes  in LCD_Data2 (High, Low), like it is in k-versions, after adding it both modules work on 1.42m.

2) this lcd module works in BGR mode, but doesn't react on command 0x36 (and most of the other control commands), so colors have to be inverted by the software, i've added inverted BGR colors to colors.h and defined LCD_BGR_SOFTWARE.

I attach changed files with fixes for the next version.

Thank you for developing this soft!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 06, 2021, 02:28:14 pm
Hi,
 It had a strange lcd module, with additional unknown chip between buffer and controller, white silicone around the controller, module was mounted on pins on the left side (not on screws). On picture "LCD modules.jpg", on left side is my lcd module from the DIY GM328 red kit.
This unknown chip is most likely a 74HC4053. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 06, 2021, 04:09:36 pm
4050 (hex high-to-low level shifter). But it's followed by another IC, which could be also a level shifter. Quite strange! The display controller isn't an ST7735 because the MADCTL command to change the color order should even work when EXTC is disabled (only system commands). And the need to /CS each byte is another strong indication. So far I haven't seen any graphics display controller which requires that. It would be great if we could figure out the controller, because I'd rather write a driver for that controller than bodging the ST7735 driver to work with the unknown controller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: b0hoon on March 06, 2021, 06:40:49 pm
By the unknown chip i meant U3.

Markings:
- on the edge: C177-237-B-P0-J-E-1 1001081122c
- underneath: CMC2P0437 V100125-B27

Google gave me nothing, unless i suck in google searching, worth to check by someone else.

During the tests i wrote a primitive lcd tester, based on the PWM menu, basically it was writing a cmd to the lcd and then one data byte. I've tested cmds from 0x00 to 0x80, with 0xff and then with 0x00 and was watching if something is going on with the display.

- 0x00 to 0x27 - no visual reaction
- 0x28 - display off - correct
- 0x29 - display on - correct
- 0x2a CMD_COL_ADDR_SET, 0x2b CMD_ROW_ADDR_SET, 0x2c CMD_MEM_WRITE - assume it worked, because it was used to display for me values, which i set
- the rest - no visual reaction.

What else can i do... Maybe i am wrong about the controller. I have a backup of the original firmware 1.12k of the tester, if there is a simple way to check what controller was compiled, without using IDA or something and analyzing the code...:)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 06, 2021, 07:57:03 pm
The best option would be to program the original firmware and use a logic analyzer to capture the LCD's initialization commands after power-on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on March 07, 2021, 09:12:23 am
When the firmware compiles without errors it should be fine. The version in the 'trunk' directory is the current k-firmware under development, similar to a beta version. With git the changes are referenced by the commit IDs. The finished versions are in 'tags'.
I worked on it again and realized that it doesn't need any file under 'Obj/mega328_st7108/dep' folder. Creating the empty 'dep' folder under 'Obj/mega328_st7108/' was enough. When I compiled again it created identical files.

Thank you for all madires! I'm planing to build another tester (with m644&ST7735) to program it with m-firmware. I'll post about it when I try.
Title: Re: $20 LCR ESR Transistor checker project
Post by: b0hoon on March 07, 2021, 02:34:31 pm
Quote
The best option would be to program the original firmware and use a logic analyzer to capture the LCD's initialization commands after power-on.

I've chosen to disassemble file. It wasn't so hard after all. LCD initialization is for ST7735, so i can confirm that i picked the correct driver. That's all i can do for now. And thank you again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 07, 2021, 03:30:35 pm
Thanks! However, I think we missed something. The original firmware sets MADCTL:
Code: [Select]
ldi     r24, 0x36       ; MEM ADDRESS CONTROL
rcall   lcd_command
ldi     r22, 0x6C
ldi     r24, 1
rcall   lcd_write_data  ; 6C = flipx + rotate + bgr, modded by someone, originally is 3C or 1C

Since the LCD module is actually 128x160 the output needs to be rotated for 160x128. After you've added the additional /CS cycle to LCD_Data2(), have you noticed the orientation of the display output? If it was correct, then MADCTL should work. Otherwise it would be the default orientation (upright, like an old mobile phone). Have you tried to enable LCD_BGR for the ST7735 driver to reverse the color order?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chaoticoz on March 07, 2021, 05:24:28 pm
Hey, this is my first post on the eevblog forums :)

I am sorry for asking, there is so much information and it is really overwhelming for me, surely this has been answered somewhere..

I have this transistor tester (https://i.imgur.com/czU94ic.jpg)

I flashed the precompiled 1.13k firmware from https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk/mega328_st7565_kit (https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk/mega328_st7565_kit)

Now i saw that there is another firmware version 1.42m, which seems more recent? The problem is i am lost trying to compile it for my tester as i really don't know where to start.

So my questions are:

-Is the 1.42m version better than the 1.13k?
-Do precompiled binaries of it exist? If not, how do i get started to compiling them?

Thank you guys!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 07, 2021, 05:50:31 pm
-Is the 1.42m version better than the 1.13k?

Not better, but it comes with several additional functions. It's explained in the README file.

-Do precompiled binaries of it exist? If not, how do i get started to compiling them?

I don't provide precompiled firmwares because I don't know which features someone likes to have. It's up to you to choose what you need. A few posts ago indman posted a link to a starter package for WinAVR which might be a good starting point.

PS: You could try the settings for the GM328 and also enable the rotary encoder (presumably PD3 and 1).
Title: Re: $20 LCR ESR Transistor checker project
Post by: b0hoon on March 07, 2021, 06:00:51 pm
Quote
Since the LCD module is actually 128x160 the output needs to be rotated for 160x128. After you've added the additional /CS cycle to LCD_Data2(), have you noticed the orientation of the display output? If it was correct, then MADCTL should work. Otherwise it would be the default orientation (upright, like an old mobile phone). Have you tried to enable LCD_BGR for the ST7735 driver to reverse the color order?

Let me show you, what i'm talking about.

1.12k OF

MEMADDRCTRL = 0x6C (flipx + hw_rotation + hw_bgr)

- both lcds work correct
- GM328A module - works correct, cause it behaves like 160x128 natively, both the lcd and the software works in bgr mode, so colors are ok too
- GM328 module - works correct, cause it reacts on hw flags (flipx, rotation and bgr), both the lcd and the software works in bgr mode, so colors are ok

1.13k compiled by me

- LCD_SCREEN_ROTATE defined, so command is MEMADDRCTRL = 0x3C (hw_rotation + hw_bgr),

- GM328A module - works correct, cause it doesn't react on hw_rotation flag, colors are ok
- GM328 module - x-flipped, cause there is no hw_flipx flag, colors are ok

1.42m

- added CS bitbanging between bytes
- defined as 128x160
- without any lcd flags like rotate, flip
- lcd_bgr defined, but not my soft bgr

- GM328A module - the display area is clipped to 128px, cause there is no rotation flag, but orientation is ok, colors are bad, cause it works in bgr mode, soft is in rgb
- GM328 module - lack of hw flags except bgr, so bad orientation, colors are bad, because it reacts on hw_bgr flag

and now without lcd_bgr flag

- GM328A module - display area and orientation is like before, colors are bad, cause it works in bgr anyway.
- GM328 module - bad orientation, colors are ok

As i said before, GM328A module doesn't react at all on command 0x36.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 07, 2021, 07:14:27 pm
I see! Thanks! So the display from the GM328A is 160x128 which is different from an ST7735's 128x160. Another detail I've spotted are the flags for MADCTL. 1.13k sets 0x3C (in m-firmware terms:  FLAG_HREFRESH_REV, FLAG_COLOR_BGR, FLAG_VREFRESH_REV and FLAG_XY_REV) while 1.42m doesn't set  FLAG_HREFRESH_REV and FLAG_VREFRESH_REV. I have the sneaky suspicion that the unknown IC on the GM328A's LCD module might be an MCU translating ST7735 commands for some other LCD controller. Using two level shifters in series doesn't make any sense. Maybe the other LCD controller plus MCU are cheaper than an ST7735?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on March 07, 2021, 07:23:31 pm
... 1.12k OF

Hallo bOhoon,

just for fun, i flashed your "Original Firmwarefiles" to my "GeekTeches GM328A" with a LCD 128X160p SPI Color TFT Module and ST7735 Controller:

It runs.

Start the calibration procedere works fine and end with hint for FW 1.12. The tester works fine also with the different components in the normal range.

But the start of the function-menu shows four entrys more then the "Orginal k1.12 version":

[attach=1]

   1.) The function >DS18B20 (1-Wire Digital Thermometer Sensor) works fine
   2.) The function >IR_Decoder fails
   3.) The function >IR_Encoder fails
   4.) The function >DHT11 fails

This additional functions are a part of m1.38 or higher, is it now a new SW-mix from the Chinese clones?

Regards
Horst

Title: Re: $20 LCR ESR Transistor checker project
Post by: b0hoon on March 07, 2021, 07:33:07 pm
Quote
I have the sneaky feeling that the unknown IC on the GM328A's LCD module might be an MCU translating ST7735 commands for some other LCD controller.

Exactly! U3 isn't another level shifter, probably it is some kind of translator.

Quote
Maybe the other LCD controller plus MCU are cheaper than an ST7735?

Well, maybe... But it's one of the most ridiculous things i ever seen :)

Quote from: Obelix2007
This additional functions are a part of m1.38 or higher, is it now a new SW-mix from the Chinese clones?

I don't really know, what to say about it. I have no idea.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chaoticoz on March 07, 2021, 07:54:45 pm
Thanks for your answer! Sadly i just killed it somehow by running it of my hacked together power supply. Set to 9V and checked with my DMM before connecting, it worked for a minute, now it's dead. Doesn't respond at all anymore :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: b0hoon on March 07, 2021, 08:24:30 pm
One more thing.

Now as i wondering about this cheapish thing on my desk, question just from pure curiosity, why LCD_BGR flag is even implemented? Is this used in some cases at all? If the software works in RGB, woudn't be better to have LCD_RGB flag and implement it by the software, in some similar way i did it?

Edit:

Nah... My logic is broken now, woudn't be better to still have flag LCD_BGR, but implemented by the software?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 07, 2021, 08:48:58 pm
just for fun, i flashed your "Original Firmwarefiles" to my "GeekTeches GM328A" with a LCD 128X160p SPI Color TFT Module and ST7735 Controller:

It runs.

The trick of the clone's firmware is to use the MADCTL command to set the right orientation and BGR color order while using BGR color codes. Since ST7735 displays are usually wired for RGB (there's also a pin to set the color order), reversing the color order by command and using BGR color codes negates the color reversal. So a genuine ST7735 display will output everything correctly. The special display ignores the MADCTL command is, but its defaults are 160x128 and BGR color order. Therefore sending BGR color codes results in a correct output.

   1.) The function >DS18B20 (1-Wire Digital Thermometer Sensor) works fine
   2.) The function >IR_Decoder fails
   3.) The function >IR_Encoder fails
   4.) The function >DHT11 fails

This additional functions are a part of m1.38 or higher, is it now a new SW-mix from the Chinese clones?

IIRC, some modded firmware was the first to support DHT11. A little bit later I added DHT11/22 to the m-firmware after a few users asked about supporting that sensor family. I'm not sure about the DS18B20, but the IR functions were introduced by the m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 07, 2021, 09:02:27 pm
Now as i wondering about this cheapish thing on my desk, question just from pure curiosity, why LCD_BGR flag is even implemented? Is this used in some cases at all? If the software works in RGB, woudn't be better to have LCD_RGB flag and implement it by the software, in some similar way i did it?

Edit:

Nah... My logic is broken now, woudn't be better to still have flag LCD_BGR, but implemented by the software?

Most displays are wired for RGB, but a few are BGR. So far I came across only ILI9481, ILI9486 and ILI9488 based displays wired for BGR. Since they all support reversing the color order via command it's simpler to make use of that instead of maintaining also a list of BGR color codes.

Edit: Also ILI9163.
Title: Re: $20 LCR ESR Transistor checker project
Post by: b0hoon on March 07, 2021, 09:10:12 pm
Fair enough. I guess there will be no support for my super tester in next version ;) That's ok. I got it running.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 10, 2021, 06:20:59 pm
FYI, the next m-firmware version will include a driver for b0hoon's ST7735 semi-compatible display. I assume that more users have (or will get) a GM328A with that special LCD module.
Title: Re: $20 LCR ESR Transistor checker project
Post by: klimm on March 16, 2021, 09:53:04 am
Interesting. It looks like you can use a junction FET as a low gain transistor - I had never thought of trying that.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=307697)

I think I stumbled into this problem of detecting the PN4117A as a NPN BJT with my multitester.
I tested also  a 2N4416  and it is recognised as a FET but it has a much higher IDSS. 
Is there a way to simple tell a FET from a BJT?
I did the usual BJT DMM test and the PN4117 behaves like a BJT  with pin2 as base
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 16, 2021, 11:17:50 am
You can check JFETs also by measuring the resistance across drain and source (gate and source shorted!). Typical values are around 100 Ohms. Do you run a current k-firmware? If that doesn't help you could try the m-firmware which comes with some additional checks to cope with JFETs with a low I_DSS.
Title: Re: $20 LCR ESR Transistor checker project
Post by: klimm on March 16, 2021, 12:21:03 pm
Thank you Madires,
I remember  I have the 1.13. I actually  bought the tester 2-3 years ago from a local builder. Don't know how to check the version.

Thanks for the other hints. I did that resistance check with GS shorted; it gives infinite resistance both ways, which it should not. I actually bought the PN4117s to be used as low leakage diodes on a null meter   
I'll build a simple BJT multivibrator to be sure.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 16, 2021, 12:40:53 pm
Don't know how to check the version.
You have k-firmware running. M-firmware is really better at identifying such JFETs. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: klimm on March 16, 2021, 12:53:11 pm
Thanks indman, I will need to find out if I can upload the m firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 16, 2021, 01:21:05 pm
Thanks for the other hints. I did that resistance check with GS shorted; it gives infinite resistance both ways, which it should not. I actually bought the PN4117s to be used as low leakage diodes on a null meter   

If you bought them via eBay or aliexpress and not from a reputable distributor there's the possibility that they could be fakes, e.g. cheap NPNs with changed markings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: klimm on March 17, 2021, 08:09:01 am
It looks the seller knew what he sent. To my inquiry he immediately commited to refund.
Well, at least I learned the fact that I need a new firmware  :)   
Thank you all for your help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 10, 2021, 06:23:18 pm
Hi! I updated the comparative table clones. Added modifications of clone T7, the number of connecting pins LCD to the base board.  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pierreraymondrondelle on April 11, 2021, 10:40:10 am
Hi, thanks for the update, My tester is a GM328 TR tester, as displayed on the LCD. The board is labelled GM328A V1.11. It's very similar to the GM328A+ of your table but with a TQFP instead of the DIL-28. If you need more for your information, I have to dismount the board from its cabinet to shoot it. Let me know.
Regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 11, 2021, 12:50:51 pm
pierreraymondrondelle,thanks! Information in the table, which I compiled, cannot be considered reliable by 100%, since there are a large number of options and modifications of the same clones manufactured by the Chinese. With all my desire, I can not put all these options in the table. Although in most cases, even sellers cannot answer your questions with sufficient confidence. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 11, 2021, 01:08:48 pm
Please enjoy the new v1.43m:
- Added R&D display driver for identifying display controllers.
- LCD_RD control signal is now optional for ILI9341, ILI9481, ILI9486 and ILI9488.
- Added modified driver for ST7735 semi-compatible displays (suggested by b0hoon4@gmail.com).
- Option to run Zener check during normal probing (HW_PROBE_ZENER, suggested by indman@EEVblog). Requires  ZENER_UNSWITCHED. Also added corresponding remote control command (V_Z).
- Added option to specify a custom voltage divider for the Zener check (ZENER_DIVIDER_CUSTOM, ZENER_R1 and ZENER_R2).
- Removed option for low resolution in Zener check and also the ZENER_HIGH_RES configuration switch.
- Updated Russian texts (thanks to indman@EEVblog).
- Optional display of pulse duration for PWM generators (PWM_SHOW_DURATION, suggested by guest "hamburger" @mikrocontroller.net).
- Source archive includes "dep" directory to make some IDEs happy (suggested by DAIRVINE@EEVblog).
- Renamed configuration switch SW_PROBE_COLORS to UI_PROBE_COLORS.
- New feature to color titles differently (UI_COLORED_TITLES) and also cursor and key hints (UI_COLORED_CURSOR).
- Updated Romanian texts (thanks to Dumidan@EEVblog).
- Updated alternative Polish texts (thanks to Jacon@EEVblog).
- Updated Spanish texts (thanks to pepe10000@EEVblog).

Available at:
- https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
- https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 11, 2021, 01:58:11 pm
Hi! I updated the comparative table clones. Added modifications of clone T7, the number of connecting pins LCD to the base board.  ;)
Sorry, I discovered small errors in the table as well as added additional information on the clone GM328A+.
I replaced the old file to a new one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pierreraymondrondelle on April 12, 2021, 10:25:15 am
Hi Indman, I understand. Great work anyway.
kind regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: g.costanza on April 14, 2021, 03:43:07 pm
When measuring a used 50v 33uf electrolytic capacitor that was removed from a circuit, why would this meter only display a capacitance reading and no ESR reading? I'm doing a recap project and it only showed capacitance on all three of the caps. It didn't show an esr reading at all. I measured several NEW caps I have that are close to those used caps in size/capacitance and the meter DID show ESR readings on those caps. Any ideas? Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 14, 2021, 04:40:23 pm
I don't know which firmware you're using, but in general a missing ESR value indicates a problem with the measurement, e.g. out of range.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on April 15, 2021, 12:09:44 pm
Hi friends! I have a GM328A tester, like the one in the photo from b0hoon. The microcontroller is installed Mega328PU-TH. I have compiled firmware 1.43M, it works, but esr is overstated by 30-40 times. With firmware 1.13K, there is no such effect, everything is correct within normal limits. This tester can only work with 8 MHz quartz, if quartz 16 - artifacts on the display ... on both firmwares. Wrt such a sadness ...  :-\
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 15, 2021, 01:14:51 pm
Do you have the ESR issue also with 1.42m and 1.40m? The broken display output can be caused by a slow level shifter or a slow display controller. You could try to slow down the display driver by adding some delay between sending bits (wait1us() or similar).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on April 15, 2021, 08:30:43 pm
To make it clear, I took a photo. One tester is Atmega328P-U, the other is Mega328PU-TH. Firmware 1.43m, display unknown model, capacitor 1000uF 6V. In the first variant esr = 0.01, in the second one esr = 0.35 Ohm. I understand that the problem is in the operation of the ADC of the Mega328PU-TH microcontroller. But firmware 1.13k 864 Mega328PU-TH works correctly, esr = 0.00 -0.01 Ohm.
I did not do the calibration, it will not change the readings significantly ... A new clone with an unknown display and a Mega 328PU-TH microcontroller cannot work correctly with firmware 1.43m, this is sad. Perhaps for this microcontroller you need to make additional changes to the firmware ...
The display can only work at a tester frequency of 8 MHz, if the crystal of the tester is 16/20 MHz, there will be debris on the screen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on April 16, 2021, 07:18:20 am
... display can only work at a tester frequency of 8 MHz, if the crystal of the tester is 16/20 MHz, there will be debris on the screen.

Hello Andrey,

at the Mikrocontroller.net I have reported on 01.05.2019 20:12 a problem with this kind of display:

https://www.mikrocontroller.net/topic/transistortester-avr?reply_to=5827593#postform (https://www.mikrocontroller.net/topic/transistortester-avr?reply_to=5827593#postform)

The driver-circuit has no connect to GND. So it works only at 8MHz. I solve this with a wire bitween GND and pin 8 of U1 CD4050B


Regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andrey on April 16, 2021, 08:56:45 am
Thank you Obelix2007!
I have a different display. There is a connection, I checked.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on April 16, 2021, 10:40:36 am
I have a different display.

... in this case, may be help markus new fw 1.43 with the modification Semi_ST7735. Description in clones-file at line 42.

Good luck, Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 16, 2021, 11:24:40 am
To make it clear, I took a photo. One tester is Atmega328P-U, the other is Mega328PU-TH. Firmware 1.43m, display unknown model, capacitor 1000uF 6V. In the first variant esr = 0.01, in the second one esr = 0.35 Ohm. I understand that the problem is in the operation of the ADC of the Mega328PU-TH microcontroller. But firmware 1.13k 864 Mega328PU-TH works correctly, esr = 0.00 -0.01 Ohm.
I did not do the calibration, it will not change the readings significantly ... A new clone with an unknown display and a Mega 328PU-TH microcontroller cannot work correctly with firmware 1.43m, this is sad. Perhaps for this microcontroller you need to make additional changes to the firmware ...

Your Mega328PU-TH should be an ATmega328P U made in Thailand. Most of my testers have also the picopower version but not the exact same type (328P AU). To be able to fix the ESR issue I need to reproduce the problem. So I'd need a tester with an ATmega328P U-TH, and which also has the ESR issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on April 22, 2021, 11:38:45 pm
Anyone added leads to their M644?  I'd like to use leads with alligator clips so I can test components taken out of equipment.  Concerned about adding errors if I do it.  The components leads are too short after being unsoldered for insertion in the M644.
Bill

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 23, 2021, 10:04:18 am
Adding short test leads works fine. And don't forget to rerun the self-adjustment. If you go for a detachable solution you can make use of the two adjustment profiles of the m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 23, 2021, 10:37:51 am
So far I've received two reports of too high ESR values. One clone with an ATmega328 and another one modified with an ATmega644. The user with the ATmega644 has two of the exact same 644s and tried the second 644 in another tester resulting also in too high ESR values. A friend of that user has the same clone with the same modifications while the ESR values are reasonable. So we checked a few things and concluded that it's not some compiler optimization issue. The problem could be related to specific ATmega chips.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Peeps on April 30, 2021, 03:46:18 am
I noticed in 1.40m and also 1.43m that when testing p-channel mosfets, the text which shows 123=GDS is correct, but the numbers on the drain and source symbol are swapped:

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 30, 2021, 11:50:39 am
I noticed in 1.40m and also 1.43m that when testing p-channel mosfets, the text which shows 123=GDS is correct, but the numbers on the drain and source symbol are swapped:

Thanks for reporting! Actually, the symbols for p-channel MOSFETs are wrong in the 24x24 symbol bitmaps because the source is supposed to be at the top. I'll update the symbols.
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on April 30, 2021, 01:15:37 pm
I noticed in 1.40m and also 1.43m that when testing p-channel mosfets, the text which shows 123=GDS is correct, but the numbers on the drain and source symbol are swapped:

What firmware do you use for the MK328?

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Peeps on May 02, 2021, 12:30:38 am
I noticed in 1.40m and also 1.43m that when testing p-channel mosfets, the text which shows 123=GDS is correct, but the numbers on the drain and source symbol are swapped:

What firmware do you use for the MK328?

Alexander.

1.43m currently. It works with minimal changes to the config, but I did disable LCD_OFFSET_X and LCD_FLIP_Y in config_328.h (display is default ST7565R) to make the display work correctly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on May 04, 2021, 11:13:46 pm
...Comments are welcome ...

Hello Yuriy,

... your Color-Testversion looks very nice, bat at my TTester GM328A I have to change some items in the Makefile befor I can test it.

For that I need the changed source-files from you so I can compile it again.

Many thanks and best regards

Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: horo on May 07, 2021, 03:07:27 pm
In addition to what I wrote, using this version of AVR-GNUToolchain 3.4.4.24 allows you to get the most compact size of the firmware, which is especially important for the small amount of memory in ATMega328.  ;)

I did a short test on my Debian system for the standard 1.43m source with two gcc versions 5.4.0 (standard Debian stable package 1:5.4.0+Atmel3.6.1-2) and 7.3.0 (provided by Arduino IDE 1.8.13) and the compiler setting "-flto", the winner is:

gcc 7.3.0 with option -flto

AVR Memory Usage
----------------
Device: atmega328
Program:   26254 bytes (80.1% Full)
(.text + .data + .bootloader)
Data:        224 bytes (10.9% Full)
(.data + .bss + .noinit)
EEPROM:      749 bytes (73.1% Full)
(.eeprom)


followed by:

gcc 5.4.0 with option -flto

AVR Memory Usage
----------------
Device: atmega328

Program:   26652 bytes (81.3% Full)
(.text + .data + .bootloader)

Data:        224 bytes (10.9% Full)
(.data + .bss + .noinit)
EEPROM:      749 bytes (73.1% Full)
(.eeprom)


gcc 7.3.0

AVR Memory Usage
----------------
Device: atmega328
Program:   26830 bytes (81.9% Full)
(.text + .data + .bootloader)
Data:        226 bytes (11.0% Full)
(.data + .bss + .noinit)
EEPROM:      749 bytes (73.1% Full)
(.eeprom)


gcc 5.4.0

AVR Memory Usage
----------------
Device: atmega328
Program:   27068 bytes (82.6% Full)
(.text + .data + .bootloader)
Data:        226 bytes (11.0% Full)
(.data + .bss + .noinit)
EEPROM:      749 bytes (73.1% Full)
(.eeprom)


All other CFLAGS (except -flto) are unchanged from the source of 1.43m:

Code: [Select]
CFLAGS = -mmcu=${MCU} -Wall -I. -Ibitmaps
CFLAGS += -DF_CPU=${FREQ}000000UL
CFLAGS += -DOSC_STARTUP=${OSC_STARTUP}
CFLAGS += -gdwarf-2 -std=gnu99 -Os -mcall-prologues
CFLAGS += -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
CFLAGS += -flto
CFLAGS += -MD -MP -MT $(*F).o -MF dep/$(@F).d

Earlier versions than atmel 3.6.1 of the toolchain (from Atmel website) did not work under Debian stable, but at least the newer version gives smaller code, so let's hope for the future.

Nevertheless it would be interesting to see the corresponding Windows build sizes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: horo on May 07, 2021, 04:00:03 pm
I have one finding with version 1.43m: when I measure two antiparallel diodes, e.g.:

1 --->|--- 2 (red)
1 ---|<--- 2 (infrared)

the component tester (AY-AT) shows:
2  ---|<--- 1 --->|--- 2
vf 1900mV 1100 mV


so the left diode is the red one and the right diode is the IR one, but the picture shows parallel diodes.

Shouldn't the picture look like below?
2  ---|<--- 1 ---|<--- 2
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on May 07, 2021, 04:21:44 pm
Nevertheless it would be interesting to see the corresponding Windows build sizes.

... this are the result in WIN7:

C:\WinAVR-20100110\bin>avr-gcc --version
avr-gcc (GCC) 7.3.0
Copyright (C) 2017 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

----------------
Device: atmega328 with option -flto

Program:   26254 bytes (80.1% Full)
(.text + .data + .bootloader)

Data:        224 bytes (10.9% Full)
(.data + .bss + .noinit)

EEPROM:      749 bytes (73.1% Full)
(.eeprom)



> Prozess beendet. Code:0
> Dauer:00:05

----------------
Device: atmega328 without option -flto

Program:   26830 bytes (81.9% Full)
(.text + .data + .bootloader)

Data:        226 bytes (11.0% Full)
(.data + .bss + .noinit)

EEPROM:      749 bytes (73.1% Full)
(.eeprom)



> Prozess beendet. Code:0
> Dauer:00:04

Best Regards
Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 07, 2021, 05:11:15 pm
I have one finding with version 1.43m: when I measure two antiparallel diodes, e.g.:

1 --->|--- 2 (red)
1 ---|<--- 2 (infrared)

Shouldn't the picture look like below?
2  ---|<--- 1 ---|<--- 2

You are right, an analogous error on the zener diode ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 07, 2021, 05:18:25 pm
Shouldn't the picture look like below?
2  ---|<--- 1 ---|<--- 2

Yep! I'll look into that issue. Thanks for reporting!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 07, 2021, 06:05:24 pm
Shouldn't the picture look like below?
2  ---|<--- 1 ---|<--- 2

In main.c in function Show_Diode() look for:
Code: [Select]
    if (A <= 3)          /* common anode or in-series */
    {
      Display_EEString(Diode_AC_str);   /* show ->|- */
    }
    else                 /* common cathode */
    {
      Display_EEString(Diode_CA_str);   /* show -|<- */
    }

Remove the lines above and change the next few to:
Code: [Select]
  if (D2)           /* second diode */
  {
    if (A == C)          /* anti-parallel */
    {
      n = D2->A;                        /* get anode */
      Display_EEString(Diode_CA_str);   /* show -|<- */
    }
    else if (A <= 3)     /* common anode or in-series */
    {
      n = D2->C;                        /* get cathode */
      Display_EEString(Diode_AC_str);   /* show ->|- */
    }
    else                 /* common cathode */
    {
      n = D2->A;                        /* get anode */
      Display_EEString(Diode_CA_str);   /* show -|<- */
    }

    ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: horo on May 08, 2021, 09:49:11 am
thx Markus, it works.
You can also remove the following redundant section where you set only n=... without Display_EE...

so the final diff to the orig 1.43m is:

Code: [Select]
--- main.c.orig 2021-03-08 19:54:05.000000000 +0100
+++ main.c 2021-05-08 11:02:36.838944180 +0200
@@ -910,26 +910,20 @@
 
   if (D2)           /* second diode */
   {
-    if (A <= 3)          /* common anode or in-series */
-    {
-      Display_EEString(Diode_AC_str);   /* show ->|- */
-    }
-    else                 /* common cathode */
-    {
-      Display_EEString(Diode_CA_str);   /* show -|<- */
-    }
-
     if (A == C)          /* anti parallel */
     {
       n = D2->A;              /* get anode */
+      Display_EEString(Diode_CA_str);   /* show -|<- */
     }
     else if (A <= 3)     /* common anode or in-series */
     {
       n = D2->C;              /* get cathode */
+      Display_EEString(Diode_AC_str);   /* show ->|- */
     }
     else                 /* common cathode */
     {
       n = D2->A;              /* get anode */
+      Display_EEString(Diode_CA_str);   /* show -|<- */
     }
 
     Display_ProbeNumber(n);             /* display pin */

@Markus: did you consider to move also your source code development into github - beside your Warehouse? This would it make easier for contributors to follow the development between version releases?
I made good experience - I develop most of my bigger personal projects in a local git repo and push it occasionally into github - either private or public.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 08, 2021, 11:08:42 am
@Markus: did you consider to move also your source code development into github - beside your Warehouse? This would it make easier for contributors to follow the development between version releases?

Maybe some day in the future, but not at the moment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: horo on May 09, 2021, 06:33:14 pm
@Markus: did you consider to move also your source code development into github - beside your Warehouse? This would it make easier for contributors to follow the development between version releases?

Maybe some day in the future, but not at the moment.

I hacked a github repo that mirrors all your releases from 0.99m up to 1.43m (+ your double diode fix) stacked as tagged commits.
No, i did not do it all by hand, bash was my friend :)

https://github.com/Ho-Ro/ComponentTester
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on May 14, 2021, 05:09:50 pm
My today fast modification: M644 Hiland and color LCD ST7735 1.8" with firmware 1.43m
(http://[attach=1])
But when want going to menu via rotary encoder i have white LCD. Any sugestions?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 14, 2021, 07:24:42 pm
Possibly one of the rotary encoder's switches is in parallel with SDA (LCD's serial data input) and when open (pulled up) the LCD sees only 1s for whatever reason. Usually the rotary encoder has in-series resistors and the ATmega prevails when driving the LCD. How did you wire the ST7735 display?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on May 15, 2021, 07:32:19 pm
ST7735 is wired like ST7565R with bitbang SPI and same CS is connected to GND (naturally i defined pins) and then i have photo from previous post with firmware versions and white LCD when want going to menu and when i plug it in CS to defined pin and physically to AtMega i have only white LCD.
My config:
Code: [Select]
/*
 *  ST7565R
 *  - SPI interface using hardware SPI
 *  - settings for Electronic Assembly EA DOGM/DOGL128-6
 */

#if 0
#define LCD_ST7565R                     /* display controller ST7565R */
#define LCD_GRAPHIC                     /* graphic display */
#define LCD_SPI                         /* SPI interface */
/* control and data lines */
#define LCD_PORT         PORTB          /* port data register */
#define LCD_DDR          DDRB           /* port data direction register */
#define LCD_RESET        PB4            /* port pin used for /RES (optional) */
//#define LCD_CS           PB2            /* port pin used for /CS1 (optional) */
#define LCD_A0           PB5            /* port pin used for A0 */
#define LCD_SCL          PB6            /* port pin used for SCL */
#define LCD_SI           PB7            /* port pin used for SI (data input) */
/* display settings */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_OFFSET_X                    /* enable x offset of 4 dots */
//#define LCD_FLIP_X                      /* enable horizontal flip */
#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     3             /* default contrast (0-63) */
/* font and symbols: vertically aligned & flipped, bank-wise grouping */
//#define FONT_6X8_VF                      /* 6x8 font */
//#define FONT_8X8_VF                     /* 8x8 font */
//#define FONT_8X16_VFP                   /* 8x16 font */
//#define FONT_6X8_ISO8859_2_VF           /* 6x8 Central European font */
#define FONT_8X8_ISO8859_2_VF           /* 8x8 Central European font */
//#define FONT_8X12T_ISO8859_2_VFP        /* thin 8x12 Central European font */
//#define FONT_8X16_ISO8859_2_VFP         /* 8x16 Central European font */
//#define FONT_8X8_WIN1251_VF             /* 8x8 cyrillic font */
//#define FONT_8X8ALT_WIN1251_VF          /* 8x8 alternative cyrillic font */
//#define FONT_8X8T_WIN1251_VF            /* thin 8x8 cyrillic font */
//#define FONT_8X12T_WIN1251_VFP          /* thin 9x12 cyrillic font */
//#define FONT_8X16_WIN1251_VFP           /* 8x16 cyrillic font */
#define SYMBOLS_24X24_VFP               /* 24x24 symbols */
/* SPI bus */
//#define SPI_HARDWARE                    /* hardware SPI */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SI         /* port pin used for MOSI */
#endif



/*
 *  ST7735
 *  - 4 wire SPI interface using hardware SPI
 */

//#if 0
#define LCD_ST7735                      /* display controller ST7735 */
#define LCD_GRAPHIC                     /* graphic display */
#define LCD_COLOR                       /* color display */
#define LCD_SPI                         /* SPI interface */
/* control and data lines */
#define LCD_PORT         PORTB          /* port data register */
#define LCD_DDR          DDRB           /* port data direction register */
#define LCD_RES          PB5            /* port pin used for /RESX (optional) */
//#define LCD_CS           PB3            /* port pin used for /CSX (optional) */
#define LCD_DC           PB4            /* port pin used for D/CX */
#define LCD_SCL          PB7            /* port pin used for SCL */
#define LCD_SDA          PB6            /* port pin used for SDA */
/* display settings */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       160            /* number of vertical dots */
//#define LCD_OFFSET_X     4               /* enable x offset of 2 or 4 dots */
//#define LCD_OFFSET_Y     2               /* enable y offset of 1 or 2 dots */
//#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y                      /* enable vertical flip */
//#define LCD_ROTATE                      /* switch X and Y (rotate by 90°) */
//#define LCD_BGR                         /* reverse red and blue color channels */
//#define LCD_LATE_ON                     /* turn on LCD after clearing it */
/* font and symbols: horizontally aligned & flipped */
//#define FONT_10X16_HF                   /* 10x16 font */
//#define FONT_6X8_ISO8859_2_HF           /* 6x8 Central European font */
#define FONT_8X8_ISO8859_2_HF           /* 8x8 Central European font */
//#define FONT_10X16_ISO8859_2_HF         /* 10x16 Central European font */
//#define FONT_8X16_WIN1251_HF            /* 8x16 cyrillic font */
//#define FONT_8X16ALT_WIN1251_HF         /* 8x16 alternative cyrillic font */
#define SYMBOLS_30X32_HF                /* 30x32 symbols */
/* SPI bus */
//#define SPI_HARDWARE                    /* hardware SPI */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SDA         /* port pin used for MOSI */
//#endif
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2021, 09:39:01 pm
Code: [Select]
#define LCD_RES          PB5            /* port pin used for /RESX (optional) */
#define LCD_DC           PB4            /* port pin used for D/CX */
#define LCD_SCL          PB7            /* port pin used for SCL */
#define LCD_SDA          PB6            /* port pin used for SDA */

PB5 and PB7 are also used for the rotary encoder. Since PB5 and 7 are switched to input mode (HiZ) to read the rotary encoder the display will see the output of the rotary encoder during that time (the display is /CS-ed all the time!). With your wiring the rotary encoder will reset the LCD controller and create clock pulses. Better use & wire PB5 for LCD_DC and PB7 for LCD_SDA. Another solution would be to wire /CS to an unused pin of the ATmega (PB2 or 3) and enable LCD_CS.

Edit: /CS wouldn't help because the rotary encoder at PB5 would still trigger the reset. But /CS plus wiring /RES to 3.3V should work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on May 17, 2021, 04:28:30 pm
I already connected the LCD_CS to the PB3 and I had a white screen all the time without even showing the firmware version.
I try PB5 for LCD_DC and PB7 for LCD_SDA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 17, 2021, 05:27:35 pm
When you wired /CS to PB3 have you also configured the firmware with "LCD_CS  PB3"?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on May 17, 2021, 08:10:01 pm
Of course!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 18, 2021, 01:46:14 am
I already connected the LCD_CS to the PB3 and I had a white screen all the time without even showing the firmware version.
I try PB5 for LCD_DC and PB7 for LCD_SDA.

See how ILI9341 is connected...
Title: Re: $20 LCR ESR Transistor checker project
Post by: el_ectron on May 18, 2021, 08:03:34 am
Hello :)

Anyone got any info regarding the more recent LCR-TC2 ?

what's inside?
just new firmware running on old hardware?
or is there more to all the extra cost? ???

any info welcome ^-^
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 18, 2021, 09:46:02 am
I already connected the LCD_CS to the PB3 and I had a white screen all the time without even showing the firmware version.

Because PB5 is still connected to /RES the rotary encoder would trigger a reset. LCD_CS can't help with that, but with LCD_SDA (PB7) since it would prevent the LCD controller to take in data when the rotary encoder is read.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Szybkijanek on May 18, 2021, 03:35:40 pm
So, LCD ST7735 works good now with this config:
Code: [Select]
#define LCD_PORT         PORTB          /* port data register */
#define LCD_DDR          DDRB           /* port data direction register */
#define LCD_RES          PB4            /* port pin used for /RESX (optional) */
//#define LCD_CS           PB3            /* port pin used for /CSX (optional) */
#define LCD_DC           PB5            /* port pin used for D/CX */
#define LCD_SCL          PB6            /* port pin used for SCL */
#define LCD_SDA          PB7            /* port pin used for SDA */
or this
Code: [Select]
#define LCD_PORT         PORTB          /* port data register */
#define LCD_DDR          DDRB           /* port data direction register */
#define LCD_RES          PB4            /* port pin used for /RESX (optional) */
#define LCD_CS           PB3            /* port pin used for /CSX (optional) */
#define LCD_DC           PB5            /* port pin used for D/CX */
#define LCD_SCL          PB6            /* port pin used for SCL */
#define LCD_SDA          PB7            /* port pin used for SDA */
Thanks guys!
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on May 21, 2021, 11:44:24 am
Very sorry if this has already been asked: is there a way to program the GM328A in circuit? Does anyone have the ICSP pinout? Or do I have to remove the Atmel chip and program it separately?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 21, 2021, 02:06:43 pm
Yes, but you need to solder six wires and somehow glue the header onto the PCB. The procedure is quite simple, e.g. https://www.instructables.com/Adding-ICSP-header-to-your-ArduinoAVR-board/. (https://www.instructables.com/Adding-ICSP-header-to-your-ArduinoAVR-board/.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on May 21, 2021, 08:57:21 pm
Thanks madires. Are the ICSP pins broken out anywhere on the board though?

Edit: It doesn't appear so.


PS: I found this schematic that an EE has reverse-engineered for the GM328A during my searches.

(https://i0.wp.com/dragaosemchama.com/wp-content/uploads/2019/04/sch2.png?ssl=1)
https://dragaosemchama.com/en/2019/04/gm328a-reverse-engineering-new-firmware-and-tetris/ (https://dragaosemchama.com/en/2019/04/gm328a-reverse-engineering-new-firmware-and-tetris/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 22, 2021, 10:14:59 am
MISO, MOSI and SCK are connected to test resistors, and RESET has a pull-up resistor. So you could solder the wires either directly to the ATmega or to the resistors which might be easier. For a schematic with designators please see https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on May 22, 2021, 11:30:11 am
...

Please, madires, or @indman if you are reading. I'm really struggling with compiling this. After spending three hours on it this evening, I finally managed to compile and upload to the Atmel328P using USBAsp and my Arduino as a shield.

However, when I load up my GM328A, all I get is a white screen. I read the 1.43m documentation and it makes reference to the LCD_SEMI_ST7735 and I used these values. Would you be able to take a look at my code from config_328.h and see where I'm going wrong?  :'(


Code: [Select]
/*
 *  ST7735
 *  - 4 wire SPI interface using bit-bang SPI
 */

//#if 0
#define LCD_ST7735  /* display controller ST7735 */
#define LCD_GRAPHIC /* graphic display */
#define LCD_COLOR   /* color display */
#define LCD_SPI     /* SPI interface */
/* control and data lines */
#define LCD_PORT PORTD /* port data register */
#define LCD_DDR DDRD   /* port data direction register */
#define LCD_RES PD0    /* port pin used for /RESX (optional) */
#define LCD_CS PD5     /* port pin used for /CSX (optional) */
#define LCD_DC PD1     /* port pin used for D/CX */
#define LCD_SCL PD2    /* port pin used for SCL */
#define LCD_SDA PD3    /* port pin used for SDA */
/* display settings */
#define LCD_DOTS_X 160 /* number of horizontal dots */
#define LCD_DOTS_Y 128 /* number of vertical dots */
//#define LCD_OFFSET_X     4               /* enable x offset of 2 or 4 dots */
//#define LCD_OFFSET_Y     2               /* enable y offset of 1 or 2 dots */
//#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y /* enable vertical flip */
//#define LCD_ROTATE /* switch X and Y (rotate by 90�) */
//#define LCD_BGR                         /* reverse red and blue color channels */
#define LCD_LATE_ON /* turn on LCD after clearing it */
/* font and symbols: horizontally aligned & flipped */
#define FONT_10X16_HF /* 10x16 font */
//#define FONT_6X8_ISO8859_2_HF           /* 6x8 Central European font */
//#define FONT_8X8_ISO8859_2_HF           /* 8x8 Central European font */
//#define FONT_10X16_ISO8859_2_HF         /* 10x16 Central European font */
//#define FONT_8X16_WIN1251_HF            /* 8x16 cyrillic font */
//#define FONT_8X16ALT_WIN1251_HF         /* 8x16 alternative cyrillic font */
#define SYMBOLS_30X32_HF /* 30x32 symbols */
/* SPI bus */
#define SPI_BITBANG       /* bit-bang SPI */
#define SPI_PORT LCD_PORT /* SPI port data register */
#define SPI_DDR LCD_DDR   /* SPI port data direction register */
#define SPI_SCK LCD_SCL   /* port pin used for SCK */
#define SPI_MOSI LCD_SDA  /* port pin used for MOSI */
//#endif


(https://i.postimg.cc/Lnw2Zzxd/IMG-20210522-213537.jpg) (https://postimg.cc/Lnw2Zzxd)

(https://i.postimg.cc/Z9hmwJkV/IMG-20210522-213546.jpg) (https://postimg.cc/Z9hmwJkV)





Also, in config.h I have uncommented #define HW_ENCODER. Further down the file, there is also

Code: [Select]
/*
 *  check for rotary encoders
 *  - uncomment to enable
 */

#define SW_ENCODER
Am I correct in having this uncommented?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 22, 2021, 11:55:32 am
de_light,the Clones file contains a working configuration for the AY-AT clone (GM328A),which you can take for a sample configuration config_328.h
You have a clone with a standard RGB display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on May 22, 2021, 12:08:17 pm
Is the clones file found in the github transistor tester warehouse? (madires)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 22, 2021, 12:24:57 pm
The "Clones" file is included in the firmware's tar.gz archive, i.e. you have it already in the directory with the source code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 23, 2021, 02:12:44 pm
Hi,

Do you can tell me what is this model LCD ? It's on new Chinese GM328A clone.

thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 23, 2021, 03:33:40 pm
Does the display module have an additional IC (U3) after the level shifter? If so, then it's some unknown LCD controller and U3 is an MCU emulating an ST7735. It will run with the semi-ST7735 driver.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 23, 2021, 05:14:06 pm
Firmware for GM328A with display of different Gamma. Last modified Ttester Karl-Heinz Kübbeler 1.13k + color
Changed some colors in the BGR version
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 23, 2021, 06:56:22 pm
To the latest question from Madires, yes an unknown MCU is used to emulated the display.

Thank for the firmwares from Yuriy_K. Does this firmware is for programming only the AT328 or it's for programming the unknown MCU ?
How to check if my display is RGB ou BGR ?

The display is very dark compared to the original display. Someone knows how to increase the intensity of the back light ?

Many thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 23, 2021, 07:42:53 pm
Yuriy_K's compiled firmwares are for the ATmega. If you use a firmware with RGB color scheme but blue and red are reversed during output you have a display with BGR color scheme. Most display controllers allow you to change the color scheme via command. However, the MCU emulating an ST7735 doesn't support that. Therefore the firmware needs to reverse red and blue also. Regarding the backlight you could try to change the dropping resistor for the LEDs carefully.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 24, 2021, 01:54:45 am
Regarding the backlight you could try to change the dropping resistor for the LEDs carefully.

220 \$\Omega\$ resistors installed, can be downgraded to 120-150  \$\Omega\$
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 24, 2021, 06:09:43 am
@Andbro and to all!
Those with a dim screen on the AY-AT(GM328A-B)!
In the power supply circuit of the screen backlite there are as many as two current-backlight resistors in series 220 ohms and the amount 440 ohms.
One stands on the red(black) board(red arrow in photo). I replaced it with a short jumper.
The second one is on a board with a display.
For normal visibility of the screen it was necessary to change it to 100 ohm resistor.
The consumption of current on the battery became 47mA screen is perfectly visible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on May 24, 2021, 08:44:49 am

My model is like on the pictures. The resistor for the display was a 510R (440R on PCB). She was replaced by a 220R. I will see if i must replaced by a 100R.

thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 24, 2021, 09:03:54 am
Andbro,you have a new type of circuit board that has not yet been considered in the forum. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on May 24, 2021, 09:55:18 am
Thanks both. Working now!
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on May 27, 2021, 08:01:45 pm
I have a rarely used M644 Tester that will not power on.  Can't see well enough o figure it out and even if I did I'm not set up for surface mount soldering.  Anyone out there that would check it out for me?

Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 28, 2021, 08:51:30 am
Hardware upgrade and update mod m-firmware 1.43m,k-firmware 1.13k for clone LCR-TC1! ;)

Hardware:
1. Removed the ATmega324PA chip. In its place, the Atmega644PA chip is installed.
2. Removed the STC15L104W chip. In its place,a small circuit board with a power management scheme proposed by madires is installed.
3. A 5-pin joystick is integrated into the circuit for more convenient control of the tester.
4. Additional parts are installed for the successful operation of the frequency meter and generator modes. To do this, I used miniature MMCX connectors.All additions are presented on the schematic diagram in the archive.
5. Instead of resistor R5(8k2), a resistor with a nominal value of 9k1 is installed. This reduced the input voltage of the 78L05 from 9.4V to 8.5V.
The test voltage of the zener diodes has decreased from 43V to 40V.
All the necessary materials for repeating my improvements are presented in the attached archive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 28, 2021, 08:56:25 am
Only for chip ATMega644 16Mhz!
Firmware:
The changes in the firmware are made to my personal taste and for a more visual and convenient control of the device's operating modes.
Improved the 8x15 font, added large question and zener symbols, as well as the standard inductance symbol.
Added a color battery status indicator. The "OK" and "WEAK" statuses are no longer displayed, but the "LOW" status remains.
The GUI and the color palette in 1.43m Mod and 1.13k Mod are made in the same style. These are my preferences.
Thank you to dear madires and Yuriy_K for your valuable advice and help!
In the archive, I compiled the firmware english for 3 variants of the clone's circuitry:
1. With the rotary encoder installed.
2. With a 5-pin joystick installed(this is my option)
3. Only one standard Test button.
I do not publish or distribute the modified versions source files. If madires likes my suggestions,I will send him all the necessary materials and he can easily use them in the next relised.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on May 28, 2021, 01:07:54 pm
I have a rarely used M644 Tester that will not power on.  Can't see well enough o figure it out and even if I did I'm not set up for surface mount soldering.  Anyone out there that would check it out for me?

Bill

... for this topic I had a contribution in the forum:

https://www.mikrocontroller.net/topic/transistortester-avr?reply_to=6439712#6439712 (https://www.mikrocontroller.net/topic/transistortester-avr?reply_to=6439712#postform)

contribution-TIME 14.10.2020 06:18

This are the GOOGLE-TRANSLATE:

Wilhelm K. wrote:
> How did you unsolder it?

Hello Wilhelm,

first I separate the solder pins directly on the TQFP housing with a
Carpet knife off. Now I can remove the pin scraps from every single PAD
unsolder. Then comes the removal of the excess solder
from the pads using end braid. Then clean with appropriate
Solvent, fix the Mega644 first with a corner pin and
align carefully, then solder on the opposite pin,
now there are only 42 left.

Then I removed the 8-pin U4 using the same method and
there the one made beforehand on a small piece of breadboard
2Transistor solution of the TC-1-MOD from Markus connected.

Before working on the controller, however, I first have the start button
away. Its solder points on the board are the right distance
for the rotary pushbuttons already known from other clones. The
Rotary encoder still needs a small 1mm hole for its GND connection
for which there is already a marking in the right place on the circuit board
is available. Next there must be a conductor path from the button connection to the
Encoder connection are severed and the other
Encoder connector on the front and back of its circuit board
respective 4 thin ground connections are released.

A 1kOhm resistor each leads from the encoder connections to the VCC
Connection and a 10kOhm to the control pins of the controller (PB5; Pin1 and
PB6; Pin2).

In addition, I have an opening for three in the side of the case
further connections are provided that connect the output (PD4; Pin13) of the
Frequency generator or PWM generator, the input for the
Frequency measurement (PB0; Pin40) and a GND connection are available
represents.

Greetings Horst

P.S. I have not (yet) exchanged the voltage regulators.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 28, 2021, 01:30:59 pm
I have a rarely used M644 Tester that will not power on.  Can't see well enough o figure it out and even if I did I'm not set up for surface mount soldering.  Anyone out there that would check it out for me?

Let's do some simple checks first. Does the LCD's backlight turn on when you press the start/test button (it should stay on as long as you press the button)? For a schematic please see https://disk.yandex.ru/d/yW8xa5NJgUo5z/Hiland%20M644.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on May 28, 2021, 01:50:57 pm
The back light does not come on.  Thanks for the schematic!!
Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 28, 2021, 02:03:25 pm
And the LED (right of the battery connector)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on May 28, 2021, 02:08:38 pm
Is Transistor T1 a 2SA673?  I can't see the text on the schematic very well.  Couldn't find it's pin out.  It has 9vdc on the two contacts that are on the same side to the single contact on the other side.
Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on May 28, 2021, 02:10:23 pm
The LED does not light up either.
Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 28, 2021, 02:15:37 pm
Yep, T1 can by any jelly bean PNP with an hFE of around 250 or higher. Do you get 5V at the output of the voltage regulator IC1 when pressing the test button?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on May 28, 2021, 02:26:17 pm
Checked all three contacts on IC1 to the GND contact on the other side and to each other.  No output voltage when pressing the test button.  Also checked both sides of C4 with no voltage see while pushing button.

Bad IC1??

Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 28, 2021, 02:31:33 pm
And also no input voltage (battery)? Then it could be a bad T1.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on May 28, 2021, 02:35:57 pm
Both the contacts on T1 that are on the same side read 9vdc to GND.
Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 28, 2021, 02:38:02 pm
Change T1, I changed mine twice, until I replaced it with a larger body ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on May 28, 2021, 02:42:14 pm
No voltage on either side of C10 or R20.  Must be T1.  What transistor did you use?
Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 28, 2021, 03:34:25 pm
Must be T1.  What transistor did you use?
PNP S9012  hFE=227. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on May 28, 2021, 03:49:58 pm
Can I use a TO92 pin type instead of a SMD 2T1 type?
Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 28, 2021, 04:00:17 pm
yes,  Ic (mA) = 500, OK!
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on May 28, 2021, 04:03:01 pm
I ordered 50 SMD type.  If I screw up I have plenty of extras!!

Thank you for the assistance!!
Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 28, 2021, 04:11:55 pm
Can I use a TO92 pin type instead of a SMD 2T1 type?
Of course, the location allows
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 28, 2021, 05:35:34 pm
In case of through-hole the BC328-40 (I_C -800 mA) is a good choice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 28, 2021, 05:44:36 pm
No, there is a two-sided mounting without pass-through holes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 28, 2021, 06:51:29 pm
The SMD equivalent (SOT-23) would be a BC808-40.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 29, 2021, 10:26:57 am
Ttesters with installed software Karl-Heinz Kübbeler 1.13k, after minor alterations, can test IGBT transistors. Everything in the picture ...

Checked out similar add-ons for ComponentTester-1.43m. With insufficient gate voltage, an additional battery allows you to get readings ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: ko4nrbs on June 01, 2021, 10:33:24 pm
I ordered 50 SMD type.  If I screw up I have plenty of extras!!

Thank you for the assistance!!
Bill
New transistor fixed it!!

Thank you.

Bill
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 03, 2021, 11:03:18 pm
Hi    Yuriy_K,

With the new GM328A model with a MCU for the display, i load by USBASP your firmware and it's over ?


Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on June 04, 2021, 03:19:40 am
With the new GM328A model with a MCU for the display, i load by USBASP your firmware and it's over ?

Your model differs from those Ttesters, which were used for debugging and adjusting the color gamma. Without seeing the back side of your display, i cannot determine the RGB or BGR gamma ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 04, 2021, 08:52:19 am
Hello Yuriy_K ,

Probably my display is BGR. After changed the frequency for 8Mhz, it's impossible to WINAVR MAKE ALL".
I have always 2 errrors.
One warning for CPU   unsigned long wish_freq;   // frequency (Hz), which you want to create
../Obj/ST7735_BGR/PinLayout.o: In function `ldata_ipp':
(.text+0x94): relocation truncated to fit: R_AVR_13_PCREL against symbol `lcd_data' defined in .text.lcd_data section in ../Obj/ST7735_BGR/lcd-routines.o
make.exe: *** [../Obj/ST7735_BGR/ST7735_BGR.elf] Error 1

thank



Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on June 04, 2021, 10:36:35 am
After changed the frequency for 8Mhz, it's impossible to WINAVR MAKE ALL".
Why are you trying to create your own firmware? You won't succeed !!! My sources are very different from the Author's.
You can only install my finished firmware using AVRDUDE ...
Added to the message on the previous page ST7735_RGB_en_8MHz.zip, sorry did not notice ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 04, 2021, 12:20:03 pm
Hi Yuriy_K,

I have questions:

- What is the difference between the firmware ST7735_BGR_en and ST7735_BGR_en1?
- The Vext is not available ?
- How work the f-Generator ?
- How can i modified battery voltage display (Display 8.15V, Real 8.9V)
- How change the rotation menu ?

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on June 04, 2021, 01:33:58 pm
I have questions:
- What is the difference between the firmware ST7735_BGR_en and ST7735_BGR_en1?
- The Vext is not available ?
- How work the f-Generator ?
- How can i modified battery voltage display (Display 8.15V, Real 8.9V)
- How change the rotation menu ?
- Changed color of double diodes, zener diodes.
- I can turn it on, it became possible after changing the fonts.
- Read the manual ...
- By changing the divider resistors after Selftest ...
...
I do not have such a Tester, I did it according to the sent Makefile and the responses of users based on the test results. So far I have not received significant comments, which means that hundreds of users are satisfied with the results.
It must be taken into account that the author's remarks about the accuracy of measuring his creation ...
If you run my firmware, show a photo of the measurement of any transistor, I will look at the color scheme.


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 04, 2021, 02:13:42 pm
- How can i modified battery voltage display (Display 8.15V, Real 8.9V)

Besides the voltage divider there's also an offset, e.g. by a reverse polarity protection diode or the PNP power switch. The offset can be set via BAT_OUT (k-firmware: Makefile), or BAT_OFFSET (m-firmware: config.h). And the voltage divider can be changed too: BAT_NUMERATOR and BAT_DENOMINATOR (k-firmware: Makefile), or BAT_R1 and BAT_R2 (m-firmware: config.h).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 04, 2021, 02:22:29 pm


I don't want a custom firmware. it's working well for me. I thought your firmware was open source.

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: kreutz on June 04, 2021, 02:49:59 pm
It is open source, but due to the amount of different implementations of the hardware you need to customize it by modifying the makefile and/or other functions/ pin arrangement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 04, 2021, 03:39:56 pm
 Hi,

The firmware from Yuriy_K is special for the GM328A with display controlled by a NONAME MCU.
I don't know if these sources can be shared.

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: apla on June 06, 2021, 10:13:55 am
Hi,

I think current firmware compile and update procedure is too complex. I don't care to lost 1K flash in order to have Arduino UART bootloader.

So, I've tried to compile 1.43m firmware with Arduino tools and after a few modifications compilation succeeds.

What I did:

Of course, nothing works after upload ;D

I've checked some obvious things.

First of all, compilation flags a little different,

Makefile:

Code: [Select]
avr-gcc -mmcu=atmega328 -Wall -I. -Ibitmaps -DF_CPU=16000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -mcall-prologues -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT main.o -MF dep/main.o.d -c main.c
Arduino:

Code: [Select]
avr-gcc -c -g -Os -w -std=gnu11 -ffunction-sections -fdata-sections -MMD -flto -fno-fat-lto-objects -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=10607 -DARDUINO_AVR_PRO -DARDUINO_ARCH_AVR -I/Users/apla/Library/Arduino15/packages/arduino/hardware/avr/1.8.3/cores/arduino -I/Users/apla/Library/Arduino15/packages/arduino/hardware/avr/1.8.3/variants/eightanaloginputs main.c -o main.c.o
Makefile have -DOSC_STARTUP=16384 -gdwarf-2 -mcall-prologues -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums and some -M flags for Makefile rules
Arduino have -ffunction-sections -fdata-sections -MMD -flto -fno-fat-lto-objects and includes cores, which is not used anyway.

Some I don't understand, will they affect resulting code or no. If someone can tell me which flag to add, I would be very grateful. Or what I should inspect.

Maybe it's not working because Arduino and TransistorTester have different entry points in flash. I spend some time reading about it, but didn't find good clear explanation.

My next problem can be with the SH1106 screen I've used. With Arduino screen runs fine, but for TransistorTester I opted for hardware I2C and maybe I have working device, but screen not works.

Maybe someone willing to help?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 06, 2021, 01:09:19 pm
Have you set the correct I2C address for the SH1106? Have you added pull-up resistors to SCL and SDA (3.3V)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: apla on June 07, 2021, 09:26:22 am
Yes, address is correct. It is default 0x78 (0x3c), have pullups. To ensure proper bus connections I'm running Arduino sketch with graphics on display before uploading TransistorTester.

Looks like I can have more answers myself. Yesterday I run out of ideas, but today I can connect LED to pin and send some message via serial port.

Will be back.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 07, 2021, 05:31:06 pm
Karl-Heinz has reorganized the repo:
- current firmware: https://github.com/kubi48/TransistorTester-source
- current docs: https://github.com/kubi48/TransistorTester-documentation
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on June 10, 2021, 04:21:48 pm
Just bought a Black BSIDE ESR02 Pro branded DTU-1701 to add to my collection of these devices.
Apart from the lack of protection I really like the form factor of these, especially as it has standard test lead 4mm jacks.
And the viewing angle of the LCD is perfect for bench use. I prefer using my MK-328 for testing transistors and components on PCB's as I made some nice thin silicone test clips.

I can confirm this one also has the 6 pin ICSP header (unpopulated) like my DTU-1701, I soldered a header in, swapped the crystal for a 16MHz version and flashed it with no issues on my TL866A through the ICSP header with the latest firmware.

You do not need to remove the PCB to fit the header, an easy way is to turn a 2.54mm pin header "upside down" and hold it with the pins just poking through the board and then solder from the top. It will solder fine as the header is through hole plated. Once this has been done just pull the black plastic spacer off the header turn it around the correct way and push it all the way back down on the pins.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 18, 2021, 08:20:32 pm
Hi,

Where i can download the latest firmware for the MK-328 ?

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on June 18, 2021, 10:57:49 pm
There may be a link in this thread somewhere where someone has compiled a firmware for the MK-328 but it probably won't be up to date.

You would be better off compiling your own firmware so it has the options that are suitable for your use.
And you can pick what font/language you want to use.

Also there is a choice of 2 different Firmwares, K Firmware (Karl-Heinz Kübbeler) and M Firmware (Markus Reschke)
This is all explained in this thread :-+

Hi,

Where i can download the latest firmware for the MK-328 ?

Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 19, 2021, 08:07:20 am
Where i can download the latest firmware for the MK-328 ?

k firmware: https://github.com/kubi48/TransistorTester-source/tree/master/trunk/mega328_MK-328
m firmware: https://github.com/kubi48/TransistorTester-source/tree/master/Markus (configure and compile)

Also there is a choice of 2 different Firmwares, K Firmware (Karl-Heinz Kübbeler) and M Firmware (Markus Frejek)

Markus Frejek originally started the project and the author of the m firmware is Markus Reschke. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on June 19, 2021, 08:10:31 am
Oops, sorry about that. Just edited my post  :palm:


Where i can download the latest firmware for the MK-328 ?

k firmware: https://github.com/kubi48/TransistorTester-source/tree/master/trunk/mega328_MK-328
m firmware: https://github.com/kubi48/TransistorTester-source/tree/master/Markus (configure and compile)

Also there is a choice of 2 different Firmwares, K Firmware (Karl-Heinz Kübbeler) and M Firmware (Markus Frejek)

Markus Frejek originally started the project and the author of the m firmware is Markus Reschke. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on June 19, 2021, 08:20:15 am
Where i can download the latest firmware for the MK-328 ?

Check out these firmwares with photo examples of measurements. When replacing quartz at 16 MHz, the ability to measure quartz up to 14 MHz and ceramic resonators has been added.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on June 21, 2021, 11:05:50 pm
Just come across a clone of a clone, a clone LCR-TC1
Very small battery, different 2 piece case and overall poor quality/soldering (pictures are after cleaning the flux off)
This came from a seller on Amazon UK. Identifiable by "please discharge before testing" instead of "Please discharge before testing" And a Purple "K" near the ZIF socket rather than a White "K".
Title: Re: $20 LCR ESR Transistor checker project
Post by: Algasman on June 23, 2021, 06:08:37 pm
I just got a LCR-TC2 delivered  :bullshit:
Payed €17,49 including shipment.
Hardware looks slightly different, it is supposed to be faster but I have nothing to compare against.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on June 23, 2021, 07:27:43 pm
That looks the same design as the LCR-T7H and some LCR-TC1 also have this board.
The only change I can see on the Plus version is the DC-DC boost circuit for the Zener test.
It still has a Atmega 324P so performance is the same, unless they have tweaked some code.
After a calibration (Short pins 1, 2 and 3) it should display the software version at the end.

Also someone at the factory forgot to solder one lead on your "Start" switch :)


I just got a LCR-TC2 delivered  :bullshit:
Payed €17,49 including shipment.
Hardware looks slightly different, it is supposed to be faster but I have nothing to compare against.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on June 24, 2021, 09:29:52 pm
...Also someone at the factory forgot to solder one lead on your "Start" switch :)
Two leads :)
Probably it's intentional.
Title: Re: $20 LCR ESR Transistor checker project
Post by: zeeloli6 on June 24, 2021, 10:18:22 pm
Interestingly the QR code on the board points to http://91make.taobao.com (http://91make.taobao.com)

Within that store this seems to be the product:
https://item.taobao.com/item.htm?id=534453342739 (https://item.taobao.com/item.htm?id=534453342739)

Google Translate has some "interesting" interpretations  ;)

"(Pirate my death family) High-speed transistor tester LCR-T7 full-color screen graphics display finished product"

"In order to fight against piracy, this version of the tester was specially made. The tester has upgraded the program. Don’t ask if I am genuine, I can take out the source code program. I have Taobao arbitration for complaints against piracy. The result of piracy is malicious competition. There is no development cost. Please support the genuine version. I will launch more upgraded versions in the future. From t1 to t8, I can come up with products. If it is not too annoying, you can continue to watch the piracy road introduced by the baby!


Welcome new and old friends to buy, overseas agents and wholesale friends want to contact us, there are surprises!


During the event, the debugging accessories and charging cable will be sent. Thank you new and old customers for your constant care."
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on June 24, 2021, 11:29:39 pm
Keeping costs down by saving solder usage.

...Also someone at the factory forgot to solder one lead on your "Start" switch :)
Two leads :)
Probably it's intentional.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 25, 2021, 02:17:17 pm
Interestingly the QR code on the board points to http://91make.taobao.com (http://91make.taobao.com)

Within that store this seems to be the product:
https://item.taobao.com/item.htm?id=534453342739 (https://item.taobao.com/item.htm?id=534453342739)

Google Translate has some "interesting" interpretations  ;)

"(Pirate my death family) High-speed transistor tester LCR-T7 full-color screen graphics display finished product"

"In order to fight against piracy, this version of the tester was specially made. The tester has upgraded the program. Don’t ask if I am genuine, I can take out the source code program. I have Taobao arbitration for complaints against piracy. The result of piracy is malicious competition. There is no development cost. Please support the genuine version. I will launch more upgraded versions in the future. From t1 to t8, I can come up with products. If it is not too annoying, you can continue to watch the piracy road introduced by the baby!

I think that guy is talking about other backyard manufacturers copying his clones. However, it's a modified version of the OSHW Transistortester which is changed intentionally to be incompatible with the standard design, i.e. for running the OSHW firmwares one has to reprogram U4 (additional management MCU) or replace U4 with a two-transistor circuit. And the firmware is a modified k-firmware. Karl-Heinz and I would prefer when tester clones are kept compatible to allow performing firmware updates easily. So much for "piracy".
Title: Re: $20 LCR ESR Transistor checker project
Post by: mspec on June 28, 2021, 06:29:16 am
I have the T3/T4 variant and have compiled the ComponentTester-1.43m file just fine but how do I update the firmware on the actual tester.
Are there any instructions for that actual part and what to use ??

Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on June 28, 2021, 09:12:10 am
... you need a isp-progammer and build in a connector to your T4:

Best Regards
Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: mspec on June 28, 2021, 09:25:50 am
... you need a isp-progammer and build in a connector to your T4:

Best Regards
Horst

Lucky I have this gathering dust then.

Do I need all the other mods it looks like you have there ??.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on June 28, 2021, 09:46:09 am
... the mod is only a rotary/switch encoder for better menu selection. No need for programming but helpfull in daily use.

Also I changing the xtal from 8 to 16 MHz.

Sorry my bad english.

Greetings Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: mspec on June 28, 2021, 10:10:58 am
Thanks for the info. Your English is great  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 28, 2021, 11:21:09 pm
Hi,

Is it possible to upgrade the MK168 ?


Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 29, 2021, 10:15:24 am
Yes, k-firmware still supports the ATmega168. However, I'd suggest to replace the 168 with a 328 to get more flash memory. This way you can use most features of the current firmwares (k & m).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 29, 2021, 10:24:51 am
I'd suggest to replace the 168 with a 328 to get more flash memory.
Madires, the ATMEGA328 processor has already been installed in the MK-168 model. The model name does not reflect its internal content. ;)
ATMEGA168 apparently installed in this model for a very long time. :D

Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 29, 2021, 11:55:11 am
Hi,

For me, inside it's a ATMEGA168P. I have found the firmware Rev804En(8Mhz), but it's for an ATMEGA328.
And if i try to makefile with PATNO = m168p, i have this message:

> "make.exe" all
rm -rf ../Obj/TransistorTester
mkdir -p ../Obj/TransistorTester
mkdir -p ../Obj/TransistorTester/dep
avr-gcc  -Wall -DNO_ICONS_DEMO -DFONT_7X12 -DWITH_SELFTEST -DAUTO_CAL -DSHORT_UNCAL_MSG -DWITH_UJT -DWITH_PUT -DFET_Idss -DWITH_AUTO_REF -DREF_C_KORR=10 -DREF_L_KORR=40 -DC_H_KORR=0 -DWITH_UART -DRMETER_WITH_L -DCAP_EMPTY_LEVEL=4 -DAUTOSCALE_ADC -DREF_R_KORR=3 -DESR_ZERO=20 -DNO_AREF_CAP -DUSE_EEPROM -DNO_LONG_PINLAYOUT -DPULLUP_DISABLE -DANZ_MESS=30 -DPOWER_OFF -DBAT_CHECK -DBAT_OUT=150 -DBAT_POOR=6400 -DBAT_NUMERATOR=133 -DBAT_DENOMINATOR=33 -DEXT_NUMERATOR=10 -DEXT_DENOMINATOR=1 -mcall-prologues -I. -DLANG_ENGLISH -DF_CPU=8000000UL -DF_CPU_HZ=8000000 -DMHZ_CPU=8 -mmcu=atmega168 -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT lcd_hw_4_bit.o -MF ../Obj/TransistorTester/dep/lcd_hw_4_bit.o.d  -ffunction-sections -fdata-sections -DSamplingADC -c -o ../Obj/TransistorTester/lcd_hw_4_bit.o ../lcd_hw_4_bit.S
avr-gcc  -Wall -DNO_ICONS_DEMO -DFONT_7X12 -DWITH_SELFTEST -DAUTO_CAL -DSHORT_UNCAL_MSG -DWITH_UJT -DWITH_PUT -DFET_Idss -DWITH_AUTO_REF -DREF_C_KORR=10 -DREF_L_KORR=40 -DC_H_KORR=0 -DWITH_UART -DRMETER_WITH_L -DCAP_EMPTY_LEVEL=4 -DAUTOSCALE_ADC -DREF_R_KORR=3 -DESR_ZERO=20 -DNO_AREF_CAP -DUSE_EEPROM -DNO_LONG_PINLAYOUT -DPULLUP_DISABLE -DANZ_MESS=30 -DPOWER_OFF -DBAT_CHECK -DBAT_OUT=150 -DBAT_POOR=6400 -DBAT_NUMERATOR=133 -DBAT_DENOMINATOR=33 -DEXT_NUMERATOR=10 -DEXT_DENOMINATOR=1 -mcall-prologues -I. -DLANG_ENGLISH -DF_CPU=8000000UL -DF_CPU_HZ=8000000 -DMHZ_CPU=8 -mmcu=atmega168 -gdwarf-2 -std=gnu99 -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT lcd-routines.o -MF ../Obj/TransistorTester/dep/lcd-routines.o.d  -ffunction-sections -fdata-sections -DSamplingADC -c -o ../Obj/TransistorTester/lcd-routines.o ../lcd-routines.c
make.exe: *** No rule to make target `../Obj/TransistorTester/i2lcd.o', needed by `../Obj/TransistorTester/TransistorTester.elf'.  Stop.

> Process Exit Code: 2
> Time Taken: 00:03

Thank for your help
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 29, 2021, 12:16:43 pm
Andbro, in what year did you buy this clone? I'm just wondering,in 2014, the Chinese already installed the 328th processor in such models. Can you show a photo of the circuit board with the processor168 installed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 29, 2021, 12:20:29 pm
make.exe: *** No rule to make target `../Obj/TransistorTester/i2lcd.o', needed by `../Obj/TransistorTester/TransistorTester.elf'.  Stop.

I there a rule like
Code: [Select]
$(OBJDIR)/i2lcd.o: ../i2lcd.S $(MKFILES)
        $(CC) $(INCLUDES) $(CFLAGS) -c -o $@ $<
in the Makefile?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 29, 2021, 12:34:10 pm
For me, inside it's a ATMEGA168P. I have found the firmware Rev804En(8Mhz), but it's for an ATMEGA328.
And if i try to makefile with PATNO = m168p, i have this message:
You used a makefile from the old revision 804, so you got an error when compiling.
In more new releases of k-firmware,the structure of the source files has been changed,so it is necessary to compile the firmware based on a makefile that corresponds to the new structure. The Default folder already has a ready-made firmware in English for ATmega168 (9V).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 29, 2021, 02:21:51 pm
Hi,


I have bought at very low price last week on Amazon. On board, you can see the year 2015. The firmware version is 1.07k.


Thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 29, 2021, 05:49:07 pm
Hi,

Problem resolved for the MK168 with ATMEGA168P. MCU replaced by ATMEGA328P and crystal 8Mhz replaced by 16Mhz.

Last question, where i can find the latest firmware for this model ?


Thank for your help and support
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 29, 2021, 09:32:12 pm
One page back I've posted the links for the repository. Presumably you need to configure and compile the firmware yourself. For the k-firmware you could try the Makefile from mega328_2X16_menu and change the MCU frequency to 16 MHz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on June 30, 2021, 08:26:07 am
Hello,

my T7 has 8mA sleep current. Did I anything wrong with compiling SW? After plugging in battery idle current is a few nA. But after the first measurement it won't go to sleep again.

@Markus
At resistor measurement with E24/E96 function will it be possible to show color code and value?
E.g. you are measuring a resistor, tester shows E24 5% 150 & 160  \$\Omega\$ and you will be able to compare colors to select the right one. At the moment you have colors or value. Maybe for SMD resistors EIA-96 code (e.g 01C = 10k) will be a nice  feature.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on June 30, 2021, 02:28:53 pm
Hi Madires,

All is working very well for my New Old Stock MK168. An ATMEGA168p  replaced by a ATMEGA328P, a crystal from 8Mhz to 16 MHz and the latest firmware.


thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 30, 2021, 02:50:58 pm
my T7 has 8mA sleep current. Did I anything wrong with compiling SW? After plugging in battery idle current is a few nA. But after the first measurement it won't go to sleep again.

Are you using the two-transistor mod? What have you set for POWER_CTRL (_PORT and _DDR)?

At resistor measurement with E24/E96 function will it be possible to show color code and value?
E.g. you are measuring a resistor, tester shows E24 5% 150 & 160  \$\Omega\$ and you will be able to compare colors to select the right one. At the moment you have colors or value.

IIRC, you can enable both (_CC and _T) at the same time.

Maybe for SMD resistors EIA-96 code (e.g 01C = 10k) will be a nice  feature.

Sounds like a good idea. I'll add it to my to-do list.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on July 01, 2021, 06:16:28 am
my T7 has 8mA sleep current. Did I anything wrong with compiling SW? After plugging in battery idle current is a few nA. But after the first measurement it won't go to sleep again.

Are you using the two-transistor mod? What have you set for POWER_CTRL (_PORT and _DDR)?
No, I'm using SW mod at U4.

Power control is set like you mentioned in "clones"
/*
 *  power control
 *  - can't be same port as ADC_PORT or R_PORT
 */

#define POWER_PORT       PORTD     /* port data register */
#define POWER_DDR        DDRD      /* port data direction register */
#define POWER_CTRL       PD2       /* controls power (1: on / 0: off) */

At resistor measurement with E24/E96 function will it be possible to show color code and value?
E.g. you are measuring a resistor, tester shows E24 5% 150 & 160  \$\Omega\$ and you will be able to compare colors to select the right one. At the moment you have colors or value.

IIRC, you can enable both (_CC and _T) at the same time.
It is working, thanks.


You wrote in "clones"
Quote
- boost converter for Zener check
  (runs all the time, non-standard voltage divider 100k/12k)
I guess you are talking about R5/R6. Which is standard value? (maybe it will be a useful info in "clones") I have two testers. One with 100k/10k and the other one with 120k/7,5k. Maybe this is already my standby problem?
Edit:
with 100k/12k  you mean R17/R18. Maybe you can add it to "clones". My one is also 100k/12k. So I need to replace it?

I guess I also found my problem about sleep current but not the solution yet. After the first power on there are still 2.2V on 5V VCC. On 78L05 IN is only 1,6V. Shorting 2.2V to discharge all Cs doesn't change anything, There are still 2.2V
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 01, 2021, 11:18:03 am
No, I'm using SW mod at U4.

Power control is set like you mentioned in "clones"

#define POWER_PORT       PORTD     /* port data register */
#define POWER_DDR        DDRD      /* port data direction register */
#define POWER_CTRL       PD2       /* controls power (1: on / 0: off) */

The settings seem to be fine. I'm wondering about the low quiescent current. With its original firmware U4 draws around 1mA or so.

You wrote in "clones"
Quote
- boost converter for Zener check
  (runs all the time, non-standard voltage divider 100k/12k)
I guess you are talking about R5/R6. Which is standard value? (maybe it will be a useful info in "clones") I have two testers. One with 100k/10k and the other one with 120k/7,5k. Maybe this is already my standby problem?
Edit:
with 100k/12k  you mean R17/R18. Maybe you can add it to "clones". My one is also 100k/12k. So I need to replace it?

The standard values for the Zener voltage divider are 180k/20k (10:1). If your tester uses a divider with a different ratio you can adjust that in config.h (enable ZENER_DIVIDER_CUSTOM, and set ZENER_R1 and ZENER_R2). No need to change resistors. The boost converter of the TC-1/T7 is running when the tester is powered on. So it shouldn't effect the quiescent current.

I guess I also found my problem about sleep current but not the solution yet. After the first power on there are still 2.2V on 5V VCC. On 78L05 IN is only 1,6V. Shorting 2.2V to discharge all Cs doesn't change anything, There are still 2.2V

Please see https://disk.yandex.ru/d/yW8xa5NJgUo5z for the schematic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 01, 2021, 12:30:41 pm
The settings seem to be fine. I'm wondering about the low quiescent current. With its original firmware U4 draws around 1mA or so.
The use of U4 is an unsuccessful circuit design solution that creates many problems in the tester's work.
The cardinal solution is to replace U4 with a circuit of 2 transistors ,which was proposed by madires and update firmware.
On my TC1 clone after deleting U4, the current consumption is 0.0042 mA(4mkA) in sleep mode. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 01, 2021, 01:35:52 pm
Chris02 said that he programmed the alternative firmware for U4 and after connecting the battery the quiescent current was just a few nA. That's what I'm curious about since the current should be much higher with U4.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 01, 2021, 01:53:09 pm
my T7 has 8mA sleep current.After plugging in battery idle current is a few nA. But after the first measurement it won't go to sleep again.
The problem with a large current consumption in sleep mode after updating the U4 alternative firmware is observed by almost every TC1-T7 owner. A lot of owners put an additional power switch due to the fact that the tester does not turn off normally,and also freezes after several measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Chris02 on July 01, 2021, 08:09:10 pm
Thanks for your replies. If the solution is to replace U4 with this simple circuit I'll do it. It is much better then having a empty tester every time you need it :)
I'll post result after mod is done.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tsmith35 on July 04, 2021, 04:42:58 am
So after looking at U4 on my TC2, I see that it is now a SOT23-6 marked B628. This corresponds to an LN3608 / SX1308 which is a high-efficiency 1.2 MHz 2A step-up converter as opposed to the STC15L104W 80c51 mcu used on prior versions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 04, 2021, 07:32:06 am
tsmith35,on the board of the T7Plus v0.1 version, the STC power management chip is marked U3.
Title: Re: $20 LCR ESR Transistor checker project
Post by: tsmith35 on July 04, 2021, 08:24:57 am
tsmith35,on the board of the T7Plus v0.1 version, the STC power management chip is marked U3.
Okay, good information to have. Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: H202 on July 06, 2021, 09:05:35 am
What "ERROR!" means during adjustment in 1.43m ?
Closed/open calibration are OK, then it displays reference/comparator voltage, and ERROR.

Measured capacitors are 1.5..2 times bigger than nominal value (1.13K firmware measures much closer to nominal).
Also it frequently can't reliably detect component on 1-3 terminals, instead uses 1-2, 1.13k detects better.

M328P @8M, powered from LiPo with XC6206.
Vref LM431, divider resistors 10K/3K 1%, but instead of 3.2..3.3V it displays Vbat=3.53..3.56V - IMHO too big difference...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 06, 2021, 11:23:54 am
What "ERROR!" means during adjustment in 1.43m ?
Closed/open calibration are OK, then it displays reference/comparator voltage, and ERROR.

That indicates that either the adjustment is skipped or a limit is exceeded:
Code: [Select]
Limits:
- probe resistance   < 1.50 Ohms for two probes in series
- probe capacitance  < 100 pF
- IO pin's internal resistance in low mode (RiL)   < 25 Ohms
- IO pin's internal resistance in high mode (RiH)  < 29 Ohms

Measured capacitors are 1.5..2 times bigger than nominal value (1.13K firmware measures much closer to nominal).
Also it frequently can't reliably detect component on 1-3 terminals, instead uses 1-2, 1.13k detects better.

M328P @8M, powered from LiPo with XC6206.
Vref LM431, divider resistors 10K/3K 1%, but instead of 3.2..3.3V it displays 3.53..3.56V - IMHO too big difference...

The transistortester is designed to run at 5 V, not 3.3. Have you adjusted BAT_OFFSET? BTW, the battery monitoring is meant to monitor the battery voltage and not Vcc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: H202 on July 06, 2021, 11:35:29 am
changes in config.h:
UREF_VCC = 3300
BAT_WEAK = 3100
BAT_LOW = 3000
BAT_R1 = 10000
BAT_R2 = 3000

in principle, battery control is not critical for me, can switch it off completely...

Quote
The transistortester is designed to run at 5 V, not 3.3
is this hardware or software limitation ?
3.3V at 8MHz must work reliably...
Title: Re: $20 LCR ESR Transistor checker project
Post by: H202 on July 06, 2021, 11:47:37 am
A4,A5,A6
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 06, 2021, 11:58:42 am
Quote
The transistortester is designed to run at 5 V, not 3.3
is this hardware or software limitation ?
3.3V at 8MHz must work reliably...

Both, because 5 V is the sweet spot when checking semiconductors. Some SCRs or TRIACs with a higher trigger voltage or current  require even more and can't be tested.
Title: Re: $20 LCR ESR Transistor checker project
Post by: H202 on July 06, 2021, 01:33:49 pm
its possible to auto-detect SSD1306/SH1106 - read register 0 before initialization.
SH1106 & clones contain 0x28/0x48/0x56 - add 2 pixel right-shift
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 06, 2021, 01:55:58 pm
Basically it should be possible to merge both drivers into one. However, the auto-detection requires an additional signal line (MISO) and the driver's size would increase (plus higher RAM usage for additional variables).
Title: Re: $20 LCR ESR Transistor checker project
Post by: H202 on July 06, 2021, 02:07:00 pm
powered from 5V - got the same "Error!".
my schematics:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 06, 2021, 02:16:50 pm
Have you set UREF_VCC back to 5000? Have you measured a film cap (220nF - 2.2µF) three times before running the self-adjustment? As I wrote above, some value might exceed the adjustment limit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 06, 2021, 02:37:45 pm
H202,show hardware tests A1-A6 with +5V VCC
Title: Re: $20 LCR ESR Transistor checker project
Post by: H202 on July 06, 2021, 03:21:15 pm
ok, now works from 5V, pity not from 3.3V.
0.22uF ceramics measured 288nF before calibration, 242nF after.
but, sometimes falsely detects 2..22uF cap on 1-2 or 2-3 pins, though cap is connected on 1-3 pins, or not connected at all...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 06, 2021, 05:01:54 pm
That is caused typically by an unstable power supply, e.g. SMPSU or lack of bypass caps. Again, with 3.3 V a lot of semiconductors can't be detected. For example, most classic MOSFETs (not logic-level types) have a V_th around 4 V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: H202 on July 06, 2021, 06:03:36 pm
I don't really need it, only R/L/C, and frequency.
thanks for the advice...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on July 12, 2021, 01:04:04 pm
@H202:

Operating on 5V power supply brings some benefits that you should take into account:

1. all digital ICs operate at a higher frequency at 5V compared to 3.3V, so you will be able to measure higher frequencies;
2. at 5V power supply you will have higher values of test currents (those passing through 680 ohms and 470 kohm), which increases the measurement accuracy for R / L / C / ESR.

The problem of portability, the power supply from the Li-Ion battery, is easily solved with a module from a power bank. It allows the controlled charging of the accumulator and ensures the 5V power supply of the tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 12, 2021, 02:19:00 pm
3.3V will also effect the measurement ranges, i.e. lower maximum resistance and worse lower limit for inductance. And the firmware would need several changes too, like adapted tables for capacitance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GianS on July 13, 2021, 10:46:11 pm
Anyone has a misaligned/titlted screen? Bought this TC1 variant from Amazon.it vendor "diymore®"
Took some photos and to me it seems to be the LCD itself that has been wrongly attached on its own board and not a soldering problem. Should I try to adjust it by resoldering? It's not really a problem but more an annoyance

And another question, since I wasn't able to find anything using the search option, isn't the power management (U5) usually a STC 15 series chip? Or am I looking at the wrong chip?
Nothing comes up looking up what is written on it
3G1K08
A772882
2044_XA (year/week code?)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 14, 2021, 07:06:04 am
3G1K08
8G1K08
http://www.stcmicro.com/stc/stc8g1k08.html (http://www.stcmicro.com/stc/stc8g1k08.html)   
https://datasheet.lcsc.com/lcsc/2011152335_STC-Micro-STC8G1K08A-36I-DFN8_C915664.pdf (https://datasheet.lcsc.com/lcsc/2011152335_STC-Micro-STC8G1K08A-36I-DFN8_C915664.pdf)
@GianS, You have one of the new variants of the clone TC1 circuit board with a different part marking U5 and a new STC processor ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on July 14, 2021, 07:41:54 am
Anyone has a misaligned/titlted screen? Bought this TC1 variant from Amazon.it vendor "diymore®"
Took some photos and to me it seems to be the LCD itself that has been wrongly attached on its own board and not a soldering problem. Should I try to adjust it by resoldering? It's not really a problem but more an annoyance

And another question, since I wasn't able to find anything using the search option, isn't the power management (U5) usually a STC 15 series chip? Or am I looking at the wrong chip?
Nothing comes up looking up what is written on it
3G1K08
A772882
2044_XA (year/week code?)


Send it back and get one from a different seller. I posted a few posts back about this TC1 from "diymore®",  it uses a clone of a clone PCB, different cheap case, misaligned LCD and really small battery.

I tried the T7 from the same seller and that has exactly the same board, casing, misaligned screen and small battery.

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3592094/#msg3592094 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3592094/#msg3592094)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 14, 2021, 09:29:30 am
Anyone has a misaligned/titlted screen? Bought this TC1 variant from Amazon.it vendor "diymore®"
Took some photos and to me it seems to be the LCD itself that has been wrongly attached on its own board and not a soldering problem. Should I try to adjust it by resoldering? It's not really a problem but more an annoyance

The display is usually a stack of the LCD and the backlight module glued together by strips of double sided tape at the edges. And that stack is glued down to the PCB also by double sided tape (sometimes sticky pads). So resoldering won't help. You can try to loosen the stack very carefully and glue it down again to the PCB.

And another question, since I wasn't able to find anything using the search option, isn't the power management (U5) usually a STC 15 series chip?

Yes. Looks like we have another designator (U4, U3 and now U5).
Title: Re: $20 LCR ESR Transistor checker project
Post by: H202 on July 14, 2021, 05:13:13 pm
Quote
the power supply from the Li-Ion battery, is easily solved with a module from a power bank
too much noise from step-up, hard to filter, I planned to completely remove switching regulators

Quote
3.3V will also effect the measurement ranges, i.e. lower maximum resistance and worse lower limit for inductance.
You calibrate pins resistance/capacitance anyway, so what the difficulty to work from stable 3V, even with higher pins resistance ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 14, 2021, 06:38:33 pm
Quote
3.3V will also effect the measurement ranges, i.e. lower maximum resistance and worse lower limit for inductance.
You calibrate pins resistance/capacitance anyway, so what the difficulty to work from stable 3V, even with higher pins resistance ?

Ohm's law! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 15, 2021, 04:04:30 pm
Quote
3.3V will also effect the measurement ranges, i.e. lower maximum resistance and worse lower limit for inductance.
You calibrate pins resistance/capacitance anyway, so what the difficulty to work from stable 3V, even with higher pins resistance ?
See how the tests should go ... and compare with yours.
Title: Re: $20 LCR ESR Transistor checker project
Post by: PBh on July 19, 2021, 03:18:29 pm
Hello everybody,
Sorry to ask such a basic question in this huge subject, but it seems i need an appropriate firmware for my GM328 board.
All details are here: https://www.eevblog.com/forum/testgear/gm328-out-of-order/msg3610441/#msg3610441 (https://www.eevblog.com/forum/testgear/gm328-out-of-order/msg3610441/#msg3610441)
Where to fine good hex file (for the moment) ?
Thanks,
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 19, 2021, 04:32:11 pm
k-firmware: https://github.com/kubi48/TransistorTester-source/tree/master/trunk/mega328_color_kit
m-firmware: https://github.com/kubi48/TransistorTester-source/tree/master/Markus (see "Clones" for AY-AT settings)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Mp3 on July 30, 2021, 02:03:39 am
I'm having a bit of trouble finding out which build is for the Bside ESR02 Pro. My AY-AT is programmed fine now, but not sure what to do for ESR02 pro
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 30, 2021, 08:12:17 am
@Mp3 https://yadi.sk/d/yW8xa5NJgUo5z/BSideESR02(DTU-1701)/Firmware/Karl-Heinz%20K%C3%BCbbeler%20/English
https://github.com/kubi48/TransistorTester-source/tree/master/trunk/mega328_st7565
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 01, 2021, 11:12:47 am
This summer's release comes with just a few changes and improvements as the garden keeps me busy.

v1.44m:
- Added output of EIA-96 code for resistor E96 norm values (SW_R_E96_EIA96, suggested by Chris02@EEVblog).
- Added support for 4-line SPI to ILI9481 and ILI9486 drivers.
- Fixed timeout issue caused by ST7920 driver (reported by ralleeiner@mikrocontroller.net).
- Changed the discharge function: in case of a discharge problem the DUT's unloaded voltage is measured and displayed by the discharge error message, e.g. a battery's unloaded voltage.
- Fixed reversed diode symbol for second diode in output of anti-parallel diodes (reported by horo@EEVblog).
- Added option for low-active backlight to HD44780 driver for PCF8574 based I2C backpack (LCD_BACKLIGHT_LOW, suggested by Andreas Deimel).
- Fixed faulty symbols for p-channel MOSFETs in 24x24 symbol bitmaps (reported by Peeps@EEVblog).

Please download at:
- https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
- https://github.com/kubi48/TransistorTester-source/tree/master/Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: s_murat on August 03, 2021, 06:47:19 am
You will not accidentally have original English firmware 1.12k for gm328a?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 03, 2021, 09:04:36 am
Have you already checked out https://disk.yandex.ru/d/yW8xa5NJgUo5z ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on August 04, 2021, 09:39:26 am
Hello!

I checked the var_romanian.h file for version 1.44m and it is correct, no changes required.

Have a good day!
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on August 15, 2021, 08:26:37 am
Hey guys, haven't posted on here for a while!

I'm trying to measure coil inductance with the tester project - is this possible? For example, I've wound a toroid on an Amidon T68-2 but whenever I connect it to my tester, it will only read a resistance. Even when I select LCR mode, it only reads a resistance.  Any suggestions?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 15, 2021, 09:07:26 am
L measured if resistance below 2100 Ω
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on August 15, 2021, 10:06:44 am
Strange. The measures resistance is around 1 ohm. It doesn't show any L values.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 15, 2021, 10:10:40 am
de_light,what clone, what firmware is used? Show photos of the inductance and measure.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 15, 2021, 10:31:42 am
The standard inductance measurement starts at about 10 µH for both OSHW firmwares. For lower values you can use the k-firmware's SamplingADC feature or the m-firmware plus the LC-meter hardware option.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on August 15, 2021, 10:59:47 pm
(https://i.ibb.co/qphpKrR/1629067811222.jpg) (https://ibb.co/qphpKrR) (https://i.ibb.co/C6ZgWZj/1629067811204.jpg) (https://ibb.co/C6ZgWZj)

Using v1.43m

Quote
The standard inductance measurement starts at about 10 µH for both OSHW firmwares. For lower values you can use the k-firmware's SamplingADC feature or the m-firmware plus the LC-meter hardware option.

Ah - this might be the issue. The inductances are low - around 1 uH
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on August 16, 2021, 04:02:13 am
Ah - this might be the issue. The inductances are low - around 1 uH
If you use my firmware from page 277, you can get this result ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 29, 2021, 04:20:38 pm
I've stumbled over LOPT/FBT testers (also called ring tester). It should be possible to design a simple hardware option for the Transistortester to do the same, i.e a test adapter for the three probes with a counter output for T0. Would you be interested in such a ring tester option?
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on August 30, 2021, 01:09:45 am
Hello!

Sorry if I'm not posting in the correct thread.

Even without components shows the value of a capacitor, what's going on?


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 30, 2021, 09:19:25 am
Could be a SMPSU powering the tester or a damaged SRV05-4 (or damaged MCU pin).
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on August 31, 2021, 04:39:06 pm
Could be a SMPSU powering the tester or a damaged SRV05-4 (or damaged MCU pin).

But sometimes the tester works normally.
That's what intrigues me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on August 31, 2021, 06:33:23 pm
Hello!

Check if:
1. The PCB is clean in the lower area, where the ZIF socket and the input protection are located; preventively clean the place, on both sides, with isopropyl alcohol using a brush with soft and long threads.
2. soldering the components on the PCB, in the area mentioned above.

What do you supply the tester with? Is it somehow a switching source? The voltage of 12V is a bit high, I recommend 7 - 9V; you can use an IC like LM7808 or 7809 between the source and the tester. Even the low power version 78L08 / 78L09 works. At the output of the LM put a capacitor of 47 - 100 uF / 16V.

If both methods do not work, it may be a defective component, most likely SRV05-4 protection.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 31, 2021, 06:35:21 pm
wandows,In such cases, careful cleaning from dirt is helped, especially ZIF socket.
To check the results of cleaning and detecting problems with board in the firmware there are T1-T7 hardware tests.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on August 31, 2021, 06:45:53 pm
I've stumbled over LOPT/FBT testers (also called ring tester). It should be possible to design a simple hardware option for the Transistortester to do the same, i.e a test adapter for the three probes with a counter output for T0. Would you be interested in such a ring tester option?

Yes; part of Bob Parker's scheme can be used. I will draw the portion I am thinking of and I will post it as soon as possible.

I tested the 1.13k version on my AY-AT and I liked the method of measuring the inductance using a standard (etalon) capacitor; can you add it in your next version?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 31, 2021, 09:06:53 pm
Sampling-ADC? Maybe in the future, but not now (lack of time).
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on August 31, 2021, 10:58:39 pm
Hello!

Sorry if I'm not posting in the correct thread.

Even without components shows the value of a capacitor, what's going on?


Hello friends!

Thanks for the valuable help in solving my tester's problem.

A thorough cleaning of the Zif socket and Srv-05 was enough to stabilize the device's operation.

Thank you all!!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on August 31, 2021, 11:18:22 pm
Hello everyone!!!
I have a device that was damaged by not discharging the electrolytic capacitor before testing.
I know when this happens the SRV-05-4 is damaged and must be replaced.
MCU gets damaged?, or just install the firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 01, 2021, 11:22:01 am
The SRV-05-4 is optional, i.e. the tester will run also without it. Remove the SRV-05-4 and check if the tester runs. If that doesn't help also remove the TVS and test again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on September 01, 2021, 06:29:10 pm
I've stumbled over LOPT/FBT testers (also called ring tester). It should be possible to design a simple hardware option for the Transistortester to do the same, i.e a test adapter for the three probes with a counter output for T0. Would you be interested in such a ring tester option?

Yes; part of Bob Parker's scheme can be used. I will draw the portion I am thinking of and I will post it as soon as possible.


Hi!

I had some time and drew two variants for the LOPT / FBT test adapter.

Both variants are designed by Bob Parker and can be found on the internet. The tester is well documented and explained. Bob also made a more complex version, based on a PIC MCU.
I built Bob's tester, the LM393 and CD4015 version and it works very well.


Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 02, 2021, 12:26:45 am
I've been following this long thread for years, and want to thank Karl-Heinz, the two Markus, indman, and the whole crew.

I have had a dozen of these component testers (haven't burn any, knock on wood), and I currently have a a T4, a TC1 (wondering how a recent m-firmware would look running on it), and other one I don't recall anyone reviewing it here, so here I go:

The PCB states WEI_M8_shell_TST. It has a 3.7V battery with a physical switch, a Mega328p, an 8MHz crystal, several scratched ICs, and 3 nice test leads plus a ZIF socket with extra PCB options, a monochrome graphics (don't know the controller). The 1.11k firmware was modified by VANVELL ELC.
I have used it for testing quite a lot of components without problems, and I'm happy with it. Nevertheless, I wonder whether somebody already updated the (k or m) firmware for it, although I've not studied how to connect the programming interface yet. Shall somebody already acmomplished this, please point me to the right place. (I could also remove/replace the 431 and try to switch to a 16MHz crystal, but first thing first).

I attach some pictures.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 02, 2021, 05:33:11 am
Feliciano,You have one of the numerous variants of the Chinese clone Wey_m8. For this clone should be firmware that lie in the "MG328" and "328WEY M8" folders on my resource https://yadi.sk/d/yW8xa5NJgUo5z
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 02, 2021, 12:51:38 pm
Looking at detailed pictures, now I see the ressemblance with the M328 WEI M8. Thanks for the hint and the links, indman. But I'm still not sure whether the display controller is a st7565.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 02, 2021, 01:06:38 pm
The LCD module looks very much like an ST7565.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 03, 2021, 11:34:24 am
Ok. I hooked my USBasp and used AVRDUDESS to erase the locked MCU and flash the 804 k-files and set the fuses. Now I have a 180º rotated screen with too much contrast (almost black background). I can barely see the text at an angle. 

I have the updated toolchain, I see where to make the changes on the makefile, but gave me an error.
shall I download the whole source code and place it on a particular location?

Edit:
I downloaded the whole source, and will try to fix the errors from programmers' notepad of WinAVR.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on September 03, 2021, 11:41:29 am
Why does the tester not read ESR sometimes?

I have an electrolytic cap, 470uF 50V.
The tester correctly identifies a capacitor, 465.6 uF, I_1 7.44uA. But not esr? Even when I select the specific esr option from the menu, still it doesn't read the esr!


Also, separate question. How normal is it to read an esr of 0.00
Is this possible?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 03, 2021, 11:47:32 am
Is your tester correctly calibrated? IIRC if the tester finds an ESR lower than the calibration offset, it generates a conflict, and perhaps that's whay it's not being shown.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 03, 2021, 11:58:52 am
or shall I download the whole source code and place it on a particular location?
Yes, you need to put all the code source(folder "Trunk")
Makefile must be used from this folder
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 03, 2021, 12:05:41 pm
Why does the tester not read ESR sometimes?
k-firmware or m-firmware? Type of clone, its model? When you are troubleshooting a problem, it is wise to include additional details about what you are using and this is important for solving the problem. Measure this capacitor on alternate firmware and compare the results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on September 03, 2021, 12:27:56 pm
It's a Gm328A running m1.43
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 03, 2021, 12:30:08 pm
Measure this capacitor on k-firmware and compare the results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 03, 2021, 01:31:01 pm
Good!. So for the V2.20 PCB is needed:
Code: [Select]
CFLAGS += -DLCD_ST7565_H_FLIP=1
CFLAGS += -DLCD_ST7565_V_FLIP=0
FLAGS += -DVOLUME_VALUE=30
And I'm provisionally setting the font to 8x8 (I think a 8x10 would be better, though).

I would like to set a vertical offset of a couple of points down. I see the setting for horizontal offset, but not the vertical offset.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 03, 2021, 01:52:21 pm
Feliciano, to correct the vertical offset in k-firmware, the display parameters must be adjusted very carefully in the lcd_defines.h file
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 03, 2021, 02:04:18 pm
Why does the tester not read ESR sometimes?

I have an electrolytic cap, 470uF 50V.
The tester correctly identifies a capacitor, 465.6 uF, I_1 7.44uA. But not esr? Even when I select the specific esr option from the menu, still it doesn't read the esr!

The m-firmware doesn't display the ESR value in case of a problem:
- capacitance too low (can't measure ESR)
- unreasonable measurement values (voltages)
- probe's zero offset higher than uncompensated ESR and capacitance lower than 1000 µF

Possible reasons:
- didn't run self-adjustment
- powered by an SMPSU
- noisy environment
- contact issues

Also, separate question. How normal is it to read an esr of 0.00
Is this possible?

Can happen for capacitors > 1000 µF when the probe's zero offset is equal to the uncompensated ESR or higher. So 0.00 Ohms basically means that the ESR is lower than what the tester is able to measure.
Title: FAQ proposal for the $20 LCR ESR Transistor checker project thread
Post by: Feliciano on September 06, 2021, 08:34:39 pm
@kubi48, @madires, @indman, @flywheelz, @blurpy, @Bohu:
Dears, I just wrote a FAQ about this component tester, so one person can get up to speed without reading this whole thread (or perhaps missing some interesting parts for him/her by just reading the last 10 pages). Because your names are in my doc, I kindly ask you whether you would like to review it privately in advance, or I rather publish it here so anyone (including you, of course) can make suggestions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 07, 2021, 07:54:37 am
Feliciano,@kubi48 and @madires have written detailed enough manuals so that a person who wants to understand the design and operation of this device, can do it themselves. For this you do not need to read this topic, enough thoughtfully read and assimilate that, what is kindly provided to us by the authors.The manual contains 99% of the answers to most of the questions mentioned in this thread.That's just my opinion.   :)
Title: Re: FAQ proposal for the $20 LCR ESR Transistor checker project thread
Post by: madires on September 07, 2021, 10:26:35 am
@kubi48 (I suppose this is KH's EEVblog username), @madires, @indman, @flywheelz, @blurpy:
Dears, I just wrote a FAQ about this component tester, so one person can get up to speed without reading this whole thread (or perhaps missing some interesting parts for him/her by just reading the last 10 pages). Because your names are in my doc, I kindly ask you whether you would like to review it privately in advance, or I rather publish it here so anyone (including you, of course) can make suggestions.

I'd suggest to open a new thread for posting and discussing your draft. The finished FAQ can be posted in this thread later on. Would this be fine with you?

I think an FAQ or quickstart guide would be helpful for some users, especially for tl;dr types.
Title: Re: FAQ proposal for the $20 LCR ESR Transistor checker project thread
Post by: indman on September 07, 2021, 11:31:20 am
Quote
I'd suggest to open a new thread for posting and discussing your draft. The finished FAQ can be posted in this thread later on. Would this be fine with you?
It would have been much more convenient to put the basic information on page 1 of this thread!
If that's not possible, perhaps a new topic could be created. On the Russian-language forum, I've posted all the useful information on page 1 in the topic header on clones. It is convenient and you do not need to look for information in other sections and topics. I have also placed a very small miniFAQ which covers only the most common issues. This is quite enough for the first acquaintance with the device. To understand it more deeply, it is necessary to get acquainted with the authors' manual in more detail.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 07, 2021, 01:33:04 pm
I also think a FAQ should have been inserted on the first page, long time ago, but as the users originally posting on this thread haven't show-up for a while, I think the options are either include it here and bookmark it for further typical questions, or create a separate thread as madires suggested. To separate the threads could confuse some users, though, as they might start to ask questions there instead of here, so it would have to make very clear from the begginging that the other thread would it be only for improving the FAQ/overview I wrote (5pages so far) or the miniFAQ (1page) indman already shared. That's why I'm scratching my head ATM.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 07, 2021, 01:38:29 pm
I'm not sure, but can't a forum moderator change (add) information on the first page on the request of other participants?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2021, 02:05:11 pm
Yes. However, it would make more sense to have a new thread just for documentation (kind of semi-locked if possible), while discussions stay here. The drawback with having a mod editing the first post is that each time something needs to be updated or changed the mod has to do that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 07, 2021, 02:23:02 pm
The drawback with having a mod editing the first post is that each time something needs to be updated or changed the mod has to do that.
Isn't a moderator's job supposed to involve that? Yes, editing will be needed, but it is not very often. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 07, 2021, 03:00:41 pm
I'm not sure how polite would it be regarding the OP to edit his/her post to add something different. Although if there is consensus about that and don't contradict the policies of EEVblog, maybe one of you could host a PDF on github or the russian server, and on the first post adding just a link to that file. That way further modifications wouldn't bother the moderators. What do you think?
to have a new thread just for documentation (kind of semi-locked if possible)
Is possible to restrict a thread to certain users? I don't know. The forum I moderate has only the option of locking a thread for read only, or unlocking it by request, but again that would involve moderators, and they're probably busy reading hundreds of posts per day.
Isn't a moderator's job supposed to involve that? Yes, editing will be needed, but it is not very often. :)
I think they're busy reading hundreds of post per day, and I'd rather not bother them with this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 07, 2021, 03:06:14 pm
Although if there is consensus about that and don't contradict the policies of EEVblog, maybe one of you could host a PDF on github or the russian server, and on the first post adding just a link to that file. That way further modifications wouldn't bother the moderators. What do you think?
I think such a solution would be ideal and I wanted to suggest that too. Madires has all the necessary materials on GitHub.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2021, 04:54:01 pm
Sounds like a reasonable idea. We could ask torch to add the link to the first post.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 07, 2021, 08:25:04 pm
@madires, @indman: you've been PM'd.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 09, 2021, 05:59:34 pm
Hello @Yuriy_K.
Your firmware came to my copy of the tester (on page 277 - ST7735_BGR_en_1).
Everything was installed without any problems. only there are no points:
- Voltage

- Front color

-Back color

- C + ESR @ TP1: 3

Front and Back colors are secondary, but -Voltage and C + ESR @ TP1: 3 I would like to have.
You wrote that you have your own sources and you just can't fix it, so the question is:
- is it possible to return these menu items to the firmware (Voltage and C + ESR @ TP1: 3)?
- if there is not enough memory (or what other reasons) can they be returned INSTEAD of points (f-generator and 10-bit PWR)?
Ideally, of course, I would leave everything ... but because of memory I think that something needs to be sacrificed))).
Also, the Switch Off menu item can be deleted (because I work from an external battery 2S-8.4V and just pull out the plug at the end)
But this is exactly what I would like to have in the firmware - are such fixes possible?
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 09, 2021, 06:32:02 pm
Vitaly_Ne,at the beginning you correctly wrote the message in English. This is an English-language forum.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 09, 2021, 07:19:21 pm
Hello.
Sorry, I fixed it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 10, 2021, 04:49:48 am
Hello @Yuriy_K.
Your firmware came to my copy of the tester (on page 277 - ST7735_BGR_en_1).
Everything was installed without any problems. only there are no points:
- Voltage
- Front color
- Back color
- C + ESR @ TP1: 3

But this is exactly what I would like to have in the firmware - are such fixes possible?

Added to the menu - Voltage, memory at the limit. Items - Front color, - Back color removed as unnecessary. Item - C + ESR @ TP1: 3 is not needed, since capacitance measurement at similar inputs duplicated this item.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stani9898 on September 10, 2021, 08:02:21 am
Hi, i bought the LCR-T4 tester but unfortunally has arrived with a broken lcd . So i have think to utilize the tester by reading the values on a pc, for example with the serial monitor. I  want know also if i can reprogram the tester in order to use an 16x2 lcd display (1602a). I don't know how to do that, so if you have any tips.. ;D. Thank you very much  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2021, 08:12:26 am
stani9898,there were a lot of people with that problem. Here is one of the solutions. In the include manual you will find the pins for the correct connection of the 1602 display to the ATMega328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stani9898 on September 10, 2021, 08:30:00 am
Is it only necessary to connect the pins correctly,as in the pdf? Or i have to modify also the hex file? Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2021, 08:32:51 am
Is it only necessary to connect the pins correctly,as in the pdf?
Just that!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 10, 2021, 09:31:27 am
Thank you very much!
Everything works fine on this firmware.

Probes (15cm with clamps at the ends), capacitors 25nF and 145nF for calibration are the same (film) as previously used (on V1.12), no changes in the type of soldering or replacement of parts were made (only a 6-pin cable is soldered for firmware).

1. What has changed (compared to the original firmware 1.12):
- the supply voltage shows more accurately (8.263V multimeter RM219 - 8.28V device) +/- 0.03V which is fine, it used to be +/- 0.2V
- subjective - it looks prettier in color)
- offhand measurements of capacitors, resistors and transistors are about the same (more precisely, then I will compare with old records)
- measurement speed is approximately the same

2. What raises questions (for me personally, although maybe I still don't understand something or haven't figured it out to the end):
- The ESR of many capacitors has become .00, although it used to show 0.03 - 0.07 .... for those that showed up to 0.2-0.8 or more, it also became almost half less ...
- when calibrating in the first steps, it shows R .00 .00 .00 although this may be the influence of the wires of the probes ... but should it be shorter with jumpers? I will understand and try))), although it measures the resistances relatively accurately (compared to RM219)

3. What I would like (if of course possible):
- completely remove auto shutdown, or make it as long as possible, or what delays to set so that it does not turn off itself ... to turn it on and until the battery is completely discharged))))
- a little bit even brighter to make the inscriptions ... otherwise it seems pale to me.

p.s. I recently had a tester, so don't judge strictly, I'm still learning to work with him)))
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 10, 2021, 09:53:04 am
p.s. I recently had a tester, so don't judge strictly, I'm still learning to work with him)))
Take out all your amateur performance if you want to have an accurate meter, not a show meter. Carry out all measurements on the standard connector, unsolder the wires for firmware, leave the pins for connecting an external cable at most. Calibrate with short shorting contacts. R0 must be different from 0.00. All the settings were made just for such measurement conditions. Read about the brightness setting on the page where the firmware -277 is published ...
Added a photo as an example of measuring SMD inductance 100 nH.
Title: Re: $20 LCR ESR Transistor checker project
Post by: stani9898 on September 10, 2021, 01:01:34 pm
Thank you very much!! It works  ;D :D

This is the guide for flasing the firmware.
https://www.instructables.com/TransistorTester-Firmware-Flash-With-Arduino/ (https://www.instructables.com/TransistorTester-Firmware-Flash-With-Arduino/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2021, 01:20:02 pm
@madires, @indman: you've been PM'd.

I've placed both FAQs in the repo: https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation/English
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 10, 2021, 07:37:41 pm
I will take into account the comments, thanks.
- I read about increasing the brightness by replacing the resistances. I shorted the resistor on the board (and also on the display) with tweezers - yes, it works. I just thought, maybe you can just fix something in the settings WITHOUT soldering to increase the contrast and brightness ... but since it is impossible, then the question is closed.

- about resistance: I soldered 3 pins from the comb (I put heat shrinkage for easy pulling out).
And .... the result is the same ... R .00 .00 .00, although measured on the same tester just as resistance shows 0.1 ohm for both.
I measured 0.08 and 0.09 ohms with a multimeter.

I made a calibration and measurements with probes, and then a calibration with a jumper and measurements directly in the ZIF-panel and ...
- there is practically no difference...
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2021, 08:03:11 pm
- about resistance: I soldered 3 pins from the comb (I put heat shrinkage for easy pulling out).
And .... the result is the same ... R .00 .00 .00, although measured on the same tester just as resistance shows 0.1 ohm for both.
I measured 0.08 and 0.09 ohms with a multimeter.
Replace the Chinese +5V stabilizer with a quality one and compare the calibration results!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 11, 2021, 02:02:17 am
I will take into account the comments, thanks.

I made a calibration and measurements with probes, and then a calibration with a jumper and measurements directly in the ZIF-panel and ...
- there is practically no difference...
I will repeat again, remove all amateur activities from the board. I pointed to the firmware cable in red. The maximum that can be left on the board without compromising work was shown by an example on my Hiland, shown by a green arrow ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 11, 2021, 05:33:12 am
...I pointed to the firmware cable in red. ...
I never would have thought that these 6-wires for firmware somehow affect the readings ... they then just "hang" in the air ...
Their length is about 10cm, they are not connected to each other ... strange. Is the device really so "capricious" that pickups from wires (which are not connected anywhere) can affect?
But I will try - remove them.
I still see that you can't do without a soldering iron ... shorten the resistance for brightness, remove these wires, and they also advised to replace the 5V stabilizer ...
Thanks for the tips, I will try ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 11, 2021, 05:39:37 am
Replace the Chinese +5V stabilizer with a quality one and compare the calibration results!
Thanks for the advice. Now the stabilizer gives out 5.04V
Do I need to look for a stabilizer that gives exactly 5.00V? Can you tell me the model? It's just that it will probably be difficult to pick up to hundredths of values ... after all, the microcircuits still have a spread.
By the way, Yuriy_K in the screenshot above showed 4.94V, it turns out you need to select a stabilizer, not higher than 5.00V?
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on September 11, 2021, 06:07:30 am
Added a photo as an example of measuring SMD inductance 100 nH.

What are you using for the contacts on your jig?  It looks really nice. I have a piece of pcb, some craft sticks, pointy bamboo skewer, and a rubber band  :-[
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 11, 2021, 07:24:16 am
What are you using for the contacts on your jig?  It looks really nice. I have a piece of pcb, some craft sticks, pointy bamboo skewer, and a rubber band  :-[
I use spring contacts from very ancient connectors. It is possible, if you have some locksmith skills, to use the contacts from the mains socket. These contacts have a large thickness, it is necessary to reduce the thickness on the anvil by forging. And cut strips 2 mm wide
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 11, 2021, 01:20:28 pm
I wonder whether it would be possible to add 8x10 font to devices with graphic display (not sure how it would look, and what space the bitmaps would take), anyways as starting pont I decided to draw the std 8x8 characters in order to understand how the rendering works. While doing so I found a little detail I think it can be improved, it's about the single quotes. AFAIK there is "'", "´", and "`" (i.e. tilted to the left, vertical, tilted to the right). On the font header file I read:
Code: [Select]
0x0C,0x0C,0x04,0x08,0x00,0x00,0x00,0x00,   /* 0x17 ´ */
.
.
.
0x0C,0x0C,0x04,0x08,0x00,0x00,0x00,0x00,   /* 0x50 ` */
Being currently the same picture for both symbols, I think it could be changed to something like:
Code: [Select]
0x30,0x30,0x20,0x10,0x00,0x00,0x00,0x00,   /* 0x17 ´ */

Edit:
Additionally, shouldn't the lowercase "q" be shifted 1column to the left as well?
Code: [Select]
0x00,0xFC,0xC6,0xC6,0xC6,0xE6,0xDC,0xC0,   /* 0x61 q */ <- original
0x00,0x7E,0x63,0x63,0x63,0x73,0x6E,0x60,   /* 0x61 q */ <- shouldn't be aligned to the left as others?

I attach pictures of what I'm talking about.

I leave my suggestions for your kind consideration.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 11, 2021, 06:58:57 pm
An 8x10 font is possible for graphic displays which don't use banks, e.g. ILI9xxx or ST7735. If you create any new font files or improve current fonts please send me a copy and I'll add them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 11, 2021, 09:36:59 pm
Thanks for the info, it would be the same for a 6x10 font, right? My current candidates, are a couple of ST7565, and a ST7735, and for what I've tried today, the 6x10 looks easier to draw.

I attach the improved font I was looking as a reference.

Regards,
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 12, 2021, 12:46:58 am
I leave my suggestions for your kind consideration.
Authors use fonts with different orientations and sizes for different displays. To adjust and create your own fonts, you need to use different graphic editors. Here are examples of such work ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 12, 2021, 02:31:28 am
Yes. Please don't get me wrong. I'm not trying to draw every character from scratch, just the needed ones and fixing the artifacts consequence of the combinations of a given source font and the tool used. In fact for optimizing that part, I'm writing a tool to allow me see the font rendering before flashing the equipment (so I can zoom in and out and judge where I need to polish more). Right now I think I will try some 6x10 as it looks easier to generate. (I'm focusing on the bitmaps first, the coding will be the second stage).

The other part of the post (the one you quoted) is about some minor details I noticed on the font I was studying. I already made some improvements and shared it for future upstream integration.

Regards,
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 12, 2021, 11:24:19 am
Thanks for the info, it would be the same for a 6x10 font, right? My current candidates, are a couple of ST7565, and a ST7735, and for what I've tried today, the 6x10 looks easier to draw.

Yep! ST7735 is fine but ST7565 uses banks/pages. The problem with banks is that they create 8 bit high bands across the display because it's the way the dots are addressed. If the height of a font matches a multiple of 8 then everything looks fine. A 6x10 font needs two banks (1 bank = 8 dots, 2 banks = 16 dots) and you'll get 6 rows of unused dots. You'll also half the number of text lines (from 8 to 4). The workaround would be to use a graphics buffer in the MCU's RAM and to copy that to the display. That's slower and we don't have sufficient RAM. The ST7735 uses an address window which can be freely set.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 15, 2021, 05:47:17 pm
Dears,

Today I found an oddball: a 2N4990 SUS (https://www.circuitstoday.com/silicon-unilateral-switch). The 1.13k firmware detects it as kinda the holy grail of PNP transistors ;); Older cloned firmware(s) detect it as completely different things  ::).

Pictures attached for your notes.

Edit:
Updated to reflect the 1.44m firmware identifies as a PUT, which I think it's better than showing a PNP or two diodes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 15, 2021, 07:46:42 pm
Makes somewhat sense. The forward breakdown happens at about 7 V which is too high for the tester's 5 V. Below the breakdown voltage there's nearly no current. But in reverse mode there's some current flowing, causing the tester to see a PNP.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 15, 2021, 10:52:00 pm
Yes, I was thinking on the same reason. Nevertheless I got curious about how it would be identified by the m-firmware, and it detects a PUT (closer to the real thing, I think, so, good job, friend). I'm updating my previuos post with your firmware reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ricktendo on September 15, 2021, 11:15:20 pm
I have a few questions, I have a Fish-8840 that I have made the battery drain fix/mod, added pin header and a DC power jack:

- I would like to know what firmware I should use? (mega328_fish8840 vs mega328_fish8840_OC vs FishTesterOC)
- Should I update the crystal from 8 to 16?
- If I do upgrade the crystal do I have to recompile the firmware for this upgrade?

Note: I do not plan on doing any further hardware mods, other than maybe upgrade the crystal oscillator (depending on what you guys advise)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 16, 2021, 10:09:31 am
- I would like to know what firmware I should use? (mega328_fish8840 vs mega328_fish8840_OC vs FishTesterOC)

Please try mega328_fish8840_OC. The OC is meant for driving 3.3 V displays without any level shifting or resistors in the signal lines.

- Should I update the crystal from 8 to 16?

The higher frequency helps a little bit with some measurements. It's up to you.

- If I do upgrade the crystal do I have to recompile the firmware for this upgrade?

Yes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ricktendo on September 17, 2021, 11:10:41 pm
Anybody have any idea what would cause this, no matter what firmware I flash (mega328_fish8840_OC, FishTesterOC, mega328_fish8840 or Original) I get this screen display

I used Teensy++ 2.0 with ArduinoISP and AVRDude cli v6.3.1.1 with the following commands

Code: [Select]
avrdude –C avrdude.conf –c avrisp –P COM5 –b 19200 –p m328p -U eeprom:w:mega328_fish8840_OC.eep:i
avrdude –C avrdude.conf –c avrisp –P COM5 –b 19200 –p m328p –U flash:w:mega328_fish8840_OC.hex:i
avrdude –C avrdude.conf –c avrisp –P COM5 –b 19200 –p m328p -U lfuse:w:0xff:m -U hfuse:w:0xd9:m -U efuse:w:0xfc:m

I also tried restoring my original backups and reset the fuses to what they were previously and same problem with the screen, could it be that I scrambled something on the LCD?

Edit: After browsing the forum I found AVRDUDESS gui and with this I was successfully able to flash my device. I did have to compile my own to FLIP LCD vertical, but other than that all good!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 19, 2021, 11:04:48 am

Edit: After browsing the forum I found AVRDUDESS gui and with this I was successfully able to flash my device. I did have to compile my own to FLIP LCD vertical, but other than that all good!
You can try this firmware,I did for my tester with the same display. If you set the crystal to 16 MHz, you can get additional functions. This firmware is for 8 MHz quartz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ricktendo on September 21, 2021, 06:10:22 pm
A feature I think would be a nice inclusion to this Swiss army knife of a device is a thermometer (similar to the FG-100) to calibrate soldering iron tips

I do not know if it would require a new PCB, or if it could simply be implemented in existing boards like the GM328A (maybe calibration would be too difficult :-// )
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 21, 2021, 07:30:01 pm
For a thermocouple you'll need a frontend plus cold junction compensation. If someone knows a suitable IC for that we might be able to add such a hardware option.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 21, 2021, 08:02:31 pm
As a first thought, it could be the typical K-thermocouple sensor of a DMM, connected to an opamp (or to an instrumentation opamp for better accuracy) converting those few mV to something less than 5V for a component tester to measure. That way you could adjust software parameters to match the slope and offset. Attached one example of such basic circuit.

Or to your exact question, an improved circuit is integrated into AD595 (https://www.analog.com/en/products/ad595.html#product-overview) (or the newer and smaller AD8495) and would allow direct connection to an ATmega (and there is also a C-code for that interface on the web).
Title: Re: $20 LCR ESR Transistor checker project
Post by: ricktendo on September 22, 2021, 05:54:26 am
Does the type of capacitor I use for calibration matter?

Can I use ceramic capacitors, what about electrolytic and smd?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 22, 2021, 07:28:54 am
"Film capacitor" usually refers to a polyester or polymer film as a dielectric - as another answer points out, metallized film capacitors are the same thing: a metal coating applied over an extremely thin polymer film to create conductive electrodes for the capacitor.

In general, ceramic capacitors are somewhat non-linear in their frequency and voltage characteristics when compared to film capacitors. Another (very minor) problem with ceramic capacitors is that they tend to behave like microphones, thus picking up ambient sound and modulating the voltage across them accordingly... :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 22, 2021, 07:56:26 am
Can I use ceramic capacitors, what about electrolytic and smd?
No, you must use capacitors with the smallest Temperature Coefficient of Capacitance.

The message \1-||- 3 >100nF" is shown in row 1 of LCD. To prepare the measurement of the comparator o set
voltage, you must connect a sucient big capacitor to pin 1 and pin 3. It should be a capacitor
with a high quality factor and a capacity between 100nF and 20F. You should never use
electrolytical capacitors, use lm capacitors instead. (Clause 5.5 page 119)

TransistorTester with AVR microcontroller
and a little more
Version 1.13k
Karl-Heinz Kubbeler
kh kuebbeler@web.de
March 8, 2018
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on September 22, 2021, 08:35:18 am
As a first thought, it could be the typical K-thermocouple sensor of a DMM, connected to an opamp (or to an instrumentation opamp for better accuracy) converting those few mV to something less than 5V for a component tester to measure. That way you could adjust software parameters to match the slope and offset. Attached one example of such basic circuit.

Or to your exact question, an improved circuit is integrated into AD595 (https://www.analog.com/en/products/ad595.html#product-overview) (or the newer and smaller AD8495) and would allow direct connection to an ATmega (and there is also a C-code for that interface on the web).
There are also ready-made modules based on MAX31855 (https://datasheets.maximintegrated.com/en/ds/MAX31855.pdf) or MAX6675  (https://datasheets.maximintegrated.com/en/ds/MAX6675.pdf)with cold junction compensation and digital output (I2C) for a few dollars, for example this one (https://www.aliexpress.com/item/32846894716.html), that could be used as an add on for this purpose
Title: Re: $20 LCR ESR Transistor checker project
Post by: ricktendo on September 22, 2021, 08:59:49 am
OK so lets say I have the following value film caps:

100nF, 150nF, 220nF, 470nF (for 1-||- 3 >100nF test)
10nF, 15nF, 22nF, 33nF (for 1-||- 3 10-30nF[L] test)

Which value would you recommend I select for calibration?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 22, 2021, 09:14:58 am
Which value would you recommend I select for calibration?
There is no need to invent anything, everything is described in detail by the author of the manual. It is necessary to use those ratings that are required for the calibration and it does not matter what particular value of capacitance from this range is used.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 22, 2021, 10:51:03 am
OK so lets say I have the following value film caps:

1   100nF, 150nF, 220nF, 470nF (for 1-||- 3 >100nF test)
2   10nF, 15nF, 22nF, 33nF (for 1-||- 3 10-30nF[L] test)

Which value would you recommend I select for calibration?
I have highlighted the capacity that I use. For the first point, the capacity value is not significant. On the second point, in addition to the value of the capacitance, the quality factor of the capacitance plays a significant role. He showed with an example in the photo how to select capacities according to the value of the figure of merit - the highest Q.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 22, 2021, 11:45:11 am
There are also ready-made modules based on MAX31855 (https://datasheets.maximintegrated.com/en/ds/MAX31855.pdf) or MAX6675  (https://datasheets.maximintegrated.com/en/ds/MAX6675.pdf)with cold junction compensation and digital output (I2C) for a few dollars, for example this one (https://www.aliexpress.com/item/32846894716.html), that could be used as an add on for this purpose

The MAX6675 looks promising as it supports a Vcc of 3.3 and 5 V. So we could wire it in parallel with the display's SPI and only need an additional I/O pin for /CS.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 26, 2021, 12:05:14 am
Yury_K, In the firmware (ST7735_BGR_en_2.zip) I made a correction of -2% in the "C (𝜇𝐹) -correction" item, so it seems to me more accurate in my copy. For some reason, this item only allows you to deposit from + 9.9% to -2% ... less than -2% already jumps back in a circle.
The instruction says "... You can set the amount of this correction with the C_H_KORR parameter in the Makefile ....". There is an inverse relationship - if in plus - then the value of the capacity shows less, in minus - the value is greater. I need to make a minus amendment.
I can't recompile your version of the firmware.
Could you build the same firmware with this one change (leave everything else as it is)?
I found this place in the Makefile in the picture ...
Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 26, 2021, 03:52:18 am
Could you build the same firmware with this one change (leave everything else as it is)?
Don't understand what prevents you from setting the desired value in the menu and saving this value for further work?
If you need to decrease the readings, the correction is positive.
Read the manual ... (it is in Russian)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 26, 2021, 08:52:35 am
Yury_K , yes, I know that ... I am doing this now.
But ... it is no longer possible to reduce it even more ... that is. -2.1% ..- 2.5% - cannot be put ...
And since these percentages can be registered programmatically, I thought, if you write down -2% in the code at once, then then I will have a "reserve" and through this item you can add extra ...
Those. already programmatically will be laid (-2%) and, if necessary, I can add something to the minus ...
I just measured a lot of capacitors and made sure that (in my copy) a -2% correction for almost all capacitors is suitable (I measured electrolytes from 2μF to 10000μF). And it ranges from (-2%) to I think about (-3%) ...
It's just that you won't be able to recompile yourself, you wrote that you have the source code slightly corrected from the original ..

p.s. the adjustment range is now from -2% to + 9.9%.
If you do not immediately "sew" (- 2%), can you expand the adjustment range?
Let's say from (-10%) to (+15%) ... or at least from (-5%) ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 26, 2021, 09:17:50 am
Yes, I know that ... I am doing this now.
But ... it is no longer possible to reduce it even more ... that is. -2.1% ..- 2.5% - cannot be put ...
Show with a specific example what you need.
I have a polymer capacitor with an inscription of 1500 uF having a real capacitance measured by MS5308, 1608 uF has a correction value of +3.2. If I set it to -2.0, then I get 1692 uF ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 26, 2021, 10:15:31 am

Show with a specific example what you need.
...
for example, a 4700mkF capacitor.
In reality, his capacity is about 4350-4400μF (a friend measured it with a more accurate device). My RM219 also shows about 4300μF.
And the tester, even with a correction (-2%), barely reaches the pre-actual capacity ...
And the opportunity to make an amendment at least (-2.5% or 3%) - NO, alas ... So I asked if you could programmatically set (-2%) and then the range of adjustments would expand (by Minus).
It would have been already (-2%) initially and I could add up to (-2%) through the menu, which in the end would give (-4%), i.e. the minus range would widen ...

in the end, to make it possible to make an amendment at least from (-5%), and not from (-2%) as it is now done in the device ...
---------
range of corrections in the tester:
"+" up to 9.9%
"-" up to -2% ... but I would like up to -5% .. -10% ....
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 26, 2021, 12:09:24 pm
for example, a 4700mkF capacitor.
Take a look at my example.
To clarify: The readings on different measuring instruments differ due to the measurement methods. For Ttester, you still need to take into account the "auto-correction", look at the second and third photos. The fourth photo shows MC5308 readings. And now the question - What is considered the correct reading for a given capacitor?

Try to reduce the voltage of the stabilizer to 4.995-5.000v and power it from a stabilized source of 9-10v ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on September 26, 2021, 03:00:38 pm
Hello everyone!

My AY-AT was damaged by not discharging the electrolytic capacitor.

The firmware on the new MCU has some issues:
     ** Very slow (2 minutes to read a 1uF ceramic capacitor);
     ** Does not accurately read components;
     ** 10 minutes to perform the self-test;

The second photo shows the reading of a 67.63nF ceramic capacitor, but the correct capacitor value is 1uF.

Could any friends help me to solve this problem?
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 26, 2021, 04:37:54 pm
....And now the question - What is considered the correct reading for a given capacitor?
Yes, all readings are correct.
Just measurements at direct or alternating current or another frequency - most likely differ ...
For household crafts, the accuracy of the multimeter is quite satisfactory and I would like the tester to match them as much as possible.
Compared to you, I have little experience and knowledge in this area, and I will not even try to prove something and argue or philosophize - which is more correct, at what frequency .. at what current, etc. really correct value ...)))
And not many have professional devices.
In your photo, the readings of the multimeter and testers practically coincide, so I would like to achieve this.
Even with (-2%) correction, my tester falls short of the error range.

It measures resistors, transistors, diodes very accurately (less than 5% error), which is quite satisfactory even with this power supply and parts inside, but with capacitors the nuances are ...
Try to reduce the voltage of the stabilizer to 4.995-5.000v and power it from a stabilized source of 9-10v ...
I just thought that it is not very difficult to change one number in the file ... it would be quite suitable for my needs.
The option with replacing the power supply, I will take into account, if it really does not work out with recompilation, but this is as a last resort ...

Suddenly, you still have time and without replacing the parts you will be able to solve the problem :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 27, 2021, 01:23:28 am
To compare these measurements against a generic DMM measurements it would be arguable, to say the least. The comparison against bench/professional meters has already been done by the developers and other supporters, and that's way they have come with several recommendations on this thread and the user manuals, and some improvements on the firmware.

To make a summary of those, IIRC, the accuracy of a component tester depends on a)the Voltage regulator precision (5%, 1%, etc.), b)the Voltage reference presicion (which should have 10x times the precision of the Voltage regulator, or be removed, and configured accordingly in the firmware), the frequency of the crystal (deppending on what you're measuring), and other factors such as whether the device has been calibrated the way is being used, and even whether is being powered from a clean steady DC voltage, or something with more or less ripple.

Bottomline, the accuracy/repeatability of the measurements can vary from one device to another.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 27, 2021, 11:28:26 am
....And now the question - What is considered the correct reading for a given capacitor?
Yes, all readings are correct.
You and everyone else.
Before correcting something, you need to conduct a thorough analysis of the measurements themselves. I am attaching a photo of the capacitors and graphs comparing the real capacitance measured by MS 5308 - according to the rest of X and the readings of Ttester - blue and UT61E - red. Hopefully it is clear that you cannot set the correction value in the ranges indicated by the red arrows. By adjusting the correction in these drop-down ranges, you automatically increase the readings of all other measurements. Obviously, it is necessary to have several high-quality (polymer) capacitors in a wide range and to choose a correction value based on the minimum deviation from their true value.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 27, 2021, 05:00:08 pm
...Before correcting something, you need to conduct a thorough analysis of the measurements themselves...
When multiple measurements are taken, some of the readings (which are out of range) can often be ignored. In such measurements, it seems to me that the main thing is to understand in "+" or in "-", on average, the tendency is observed.

In general, the google translator probably did not quite correctly translate my request.
The point was that I want to check whether the range for correction will expand, if we make an amendment to the file before compilation.
I repeat, now you can only correct up to -2%.
And I just wanted to check whether it is possible to programmatically expand the adjustment range, or if it is generally possible to do so ...
There are no complaints about the firmware, I just need to check my copy of the tester ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 28, 2021, 01:55:59 am
I repeat, now you can only correct up to -2%.
On my Ttesters, the correction 2.8-3.2 is set for correct readings, as a result, we have a margin of about 5% in both directions. This amendment is used in more than one place in the source texts and is associated with displacement. I'm not going to change anything. There is a need, experiment yourself ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on September 28, 2021, 11:25:52 am
...There is a need, experiment yourself ...
There are nuances. There was a desire to check with your modified files, and not with the original ones. But since they are not freely available, that's why I asked you to correct them yourself.
But in any case, the question is closed.
I checked on the original ones - I can't add more (-2%) to the file. I tried and (-5%) bet, it still resets to (-2%).
so you won't be able to make amendments smaller (-2%) without editing the code elsewhere.
Thank you for your answers and clarifications.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on September 28, 2021, 11:48:59 am
I have a rarely used M644 Tester that will not power on.  Can't see well enough o figure it out and even if I did I'm not set up for surface mount soldering.  Anyone out there that would check it out for me?

Bill

... for this topic I had a contribution in the forum:

https://www.mikrocontroller.net/topic/transistortester-avr?reply_to=6439712#postform (https://www.mikrocontroller.net/topic/transistortester-avr?reply_to=6439712#postform)

contribution-TIME 14.10.2020 06:18

This are the GOOGLE-TRANSLATE:

Wilhelm K. wrote:
> How did you unsolder it?

Hello Wilhelm,

first I separate the solder pins directly on the TQFP housing with a
Carpet knife off. Now I can remove the pin scraps from every single PAD
unsolder. Then comes the removal of the excess solder
from the pads using end braid. Then clean with appropriate
Solvent, fix the Mega644 first with a corner pin and
align carefully, then solder on the opposite pin,
now there are only 42 left.

Then I removed the 8-pin U4 using the same method and
there the one made beforehand on a small piece of breadboard
2Transistor solution of the TC-1-MOD from Markus connected.

Before working on the controller, however, I first have the start button
away. Its solder points on the board are the right distance
for the rotary pushbuttons already known from other clones. The
Rotary encoder still needs a small 1mm hole for its GND connection
for which there is already a marking in the right place on the circuit board
is available. Next there must be a conductor path from the button connection to the
Encoder connection are severed and the other
Encoder connector on the front and back of its circuit board
respective 4 thin ground connections are released.

A 1kOhm resistor each leads from the encoder connections to the VCC
Connection and a 10kOhm to the control pins of the controller (PB5; Pin1 and
PB6; Pin2).

In addition, I have an opening for three in the side of the case
further connections are provided that connect the output (PD4; Pin13) of the
Frequency generator or PWM generator, the input for the
Frequency measurement (PB0; Pin40) and a GND connection are available
represents.

Greetings Horst

P.S. I have not (yet) exchanged the voltage regulators.

Hi.. can anyone explain about this R15 and C19 modification? I just saw this mod how can you explain what the function of this change is, what is the recommended resistor and capacitor size?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 28, 2021, 01:07:48 pm
Hi.. can anyone explain about this R15 and C19 modification? I just saw this mod how can you explain what the function of this change is, what is the recommended resistor and capacitor size?
See the end of page 276 in my post for the Hiland diagram. These details are for auto-calibrating the capacity, but this must be written in the config ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on September 28, 2021, 02:03:58 pm
Hi.. can anyone explain about this R15 and C19 modification? I just saw this mod how can you explain what the function of this change is, what is the recommended resistor and capacitor size?
See the end of page 276 in my post for the Hiland diagram. These details are for auto-calibrating the capacity, but this must be written in the config ...

yes, I have seen your schematic on page 267, the capacitor was changed to 229nf and the resistor written was 470k ohm the same as the original resistor, but in the mod picture, the smd resistor was connected in parallel with the film resistor, then removed the original capacitor and replaced it with a 220nf wima
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 28, 2021, 02:47:32 pm
yes, I have seen your schematic on page 267, the capacitor was changed to 229nf and the resistor written was 470k ohm the same as the original resistor, but in the mod picture, the smd resistor was connected in parallel with the film resistor, then removed the original capacitor and replaced it with a 220nf wima
Why are these changes? It is easier to leave it as it was, but to register the necessary settings in the config file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on September 28, 2021, 03:33:00 pm
yes, I have seen your schematic on page 267, the capacitor was changed to 229nf and the resistor written was 470k ohm the same as the original resistor, but in the mod picture, the smd resistor was connected in parallel with the film resistor, then removed the original capacitor and replaced it with a 220nf wima
Why are these changes? It is easier to leave it as it was, but to register the necessary settings in the config file.

Yes, I just saw in the post, I thought this change was for the purpose of better refinement, if it turns out to be the same as the default size of the T7 scheme then I keep the authenticity. It's good enough now I'm using it and with your firmware mod, Thanks Yuriy_K
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 29, 2021, 09:09:04 pm
I have a rarely used M644 Tester that will not power on.  Can't see well enough o figure it out and even if I did I'm not set up for surface mount soldering.  Anyone out there that would check it out for me?

Bill

... for this topic I had a contribution in the forum:

https://www.mikrocontroller.net/topic/transistortester-avr?reply_to=6439712#postform (https://www.mikrocontroller.net/topic/transistortester-avr?reply_to=6439712#postform)

contribution-TIME 14.10.2020 06:18

This are the GOOGLE-TRANSLATE:

Wilhelm K. wrote:
> How did you unsolder it?

Hello Wilhelm,

first I separate the solder pins directly on the TQFP housing with a
Carpet knife off. Now I can remove the pin scraps from every single PAD
unsolder. Then comes the removal of the excess solder
from the pads using end braid. Then clean with appropriate
Solvent, fix the Mega644 first with a corner pin and
align carefully, then solder on the opposite pin,
now there are only 42 left.

Then I removed the 8-pin U4 using the same method and
there the one made beforehand on a small piece of breadboard
2Transistor solution of the TC-1-MOD from Markus connected.

Before working on the controller, however, I first have the start button
away. Its solder points on the board are the right distance
for the rotary pushbuttons already known from other clones. The
Rotary encoder still needs a small 1mm hole for its GND connection
for which there is already a marking in the right place on the circuit board
is available. Next there must be a conductor path from the button connection to the
Encoder connection are severed and the other
Encoder connector on the front and back of its circuit board
respective 4 thin ground connections are released.

A 1kOhm resistor each leads from the encoder connections to the VCC
Connection and a 10kOhm to the control pins of the controller (PB5; Pin1 and
PB6; Pin2).

In addition, I have an opening for three in the side of the case
further connections are provided that connect the output (PD4; Pin13) of the
Frequency generator or PWM generator, the input for the
Frequency measurement (PB0; Pin40) and a GND connection are available
represents.

Greetings Horst

P.S. I have not (yet) exchanged the voltage regulators.

Hi.. can anyone explain about this R15 and C19 modification? I just saw this mod how can you explain what the function of this change is, what is the recommended resistor and capacitor size?

The reason for the modifications to my "Multi-function Tester-TC1 -T7 -T7-H" was a problem with my TT-Hiland644. So I looked for other TT clones with Mega644. In the WWW there were references to the multi-function testers with Mega644 MCU.

After buying these testers, however, I discovered that they all had a Mega324 MCU.

So I installed the 644 MCU in the TC-1 and T7 and the 1284 MCU in the T7-H. On this occasion I also attached a ROTARY ENCODER, SPI interface and 3 additional sockets for frequency input and output.

However, the actual hFE problem has not yet been resolved.

Incidentally, the additional resistor in parallel with R15 was a bug and has been removed. C19 is always exchanged for a 220nF foil capacitor, if only because the original ceramic capacitor in all clones that I own was smaller than 100nF. The advantages of the foil capacitors at this point are explained by Karl-Heinz and Markus in their documentation.

Greetings Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: ilcaccillo on September 29, 2021, 11:20:52 pm
Does anyone know at which Frequency is Inductance tested with this unit?

thank you so much
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 30, 2021, 11:23:22 am
No AC test signal - no frequency. ;) The inductance measurement is based on i_L(t) = I_0 * (1 - e^(-t R / L)). The SamplingADC is a different story, the LC meter hardware option too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on September 30, 2021, 02:11:15 pm

The reason for the modifications to my "Multi-function Tester-TC1 -T7 -T7-H" was a problem with my TT-Hiland644. So I looked for other TT clones with Mega644. In the WWW there were references to the multi-function testers with Mega644 MCU.

After buying these testers, however, I discovered that they all had a Mega324 MCU.

So I installed the 644 MCU in the TC-1 and T7 and the 1284 MCU in the T7-H. On this occasion I also attached a ROTARY ENCODER, SPI interface and 3 additional sockets for frequency input and output.

However, the actual hFE problem has not yet been resolved.

Incidentally, the additional resistor in parallel with R15 was a bug and has been removed. C19 is always exchanged for a 220nF foil capacitor, if only because the original ceramic capacitor in all clones that I own was smaller than 100nF. The advantages of the foil capacitors at this point are explained by Karl-Heinz and Markus in their documentation.

Greetings Horst

and if when replacing C19 with 220nf should also change the config for the firmware?

Another question about frequency, I use T7 gen 1 maybe the same as TC1 only the difference is in STEP UP without a transformer, I use STRIP GRID 7 configuration, is the wire frequency IN on PD4 and OUT Generator on PB0? I saw hiland644 they added 74HCxxxx

and T7 without components 74HCxxxx the IN-F and OUT-G frequencies will work for  T7  ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on October 01, 2021, 12:13:09 am
and if when replacing C19 with 220nf should also change the config for the firmware?

Another question about frequency, I use T7 gen 1 maybe the same as TC1 only the difference is in STEP UP without a transformer, I use STRIP GRID 7 configuration, is the wire frequency IN on PD4 and OUT Generator on PB0? I saw hiland644 they added 74HCxxxx

and T7 without components 74HCxxxx the IN-F and OUT-G frequencies will work for  T7  ?

... changing from C19 does not require any changes to the firmware.

Yes, the frequency IN connection goes to PD4 (pin 13) and the f-generator OUT connection to PB0 (pin 40).

The T7 does not use any 74HCxxxx components. In the HilandM644 an extended Frequency and crystal measurements carried out.

Greetings Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: ilcaccillo on October 01, 2021, 02:12:48 am
No AC test signal - no frequency. ;) The inductance measurement is based on i_L(t) = I_0 * (1 - e^(-t R / L)). The SamplingADC is a different story, the LC meter hardware option too.

Hi mate,
thank you so much for the reply and info.

Do you think it's possible or do you have the patience to explain that in other words so an ignorant (not knowledgeable) person like me could understand?

Thank you so much Madires
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 01, 2021, 02:24:26 am
and if when replacing C19 with 220nf should also change the config for the firmware?

Another question about frequency, I use T7 gen 1 maybe the same as TC1 only the difference is in STEP UP without a transformer, I use STRIP GRID 7 configuration, is the wire frequency IN on PD4 and OUT Generator on PB0? I saw hiland644 they added 74HCxxxx

and T7 without components 74HCxxxx the IN-F and OUT-G frequencies will work for  T7  ?

... changing from C19 does not require any changes to the firmware.

Yes, the frequency IN connection goes to PD4 (pin 13) and the f-generator OUT connection to PB0 (pin 40).

The T7 does not use any 74HCxxxx components. In the HilandM644 an extended Frequency and crystal measurements carried out.

Greetings Horst


I have replaced the C19 with 220nf, then I did a calibration (selftest). for the measurement results in my opinion to be inappropriate in T7. capacitor 470nf result 504nf, 4.7uf result 5.2uf, for 10uf result 11.376uf, and 22uf result 24,211uf.

I haven't tried other components, but these measurements don't fit my T7
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 01, 2021, 10:43:51 am
Do you think it's possible or do you have the patience to explain that in other words so an ignorant (not knowledgeable) person like me could understand?

There's a chapter about the inductance measurement (also for the SamplingADC method) in Karl-Heinz' excellent documentation. And for the m-firmware you can find an explanation in inductance.c. It's boring physics. ;D Or see any suitable physics book/text/webpage about inductance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 01, 2021, 02:27:16 pm
and if when replacing C19 with 220nf should also change the config for the firmware?

Another question about frequency, I use T7 gen 1 maybe the same as TC1 only the difference is in STEP UP without a transformer, I use STRIP GRID 7 configuration, is the wire frequency IN on PD4 and OUT Generator on PB0? I saw hiland644 they added 74HCxxxx

and T7 without components 74HCxxxx the IN-F and OUT-G frequencies will work for  T7  ?

... changing from C19 does not require any changes to the firmware.

Yes, the frequency IN connection goes to PD4 (pin 13) and the f-generator OUT connection to PB0 (pin 40).

The T7 does not use any 74HCxxxx components. In the HilandM644 an extended Frequency and crystal measurements carried out.

Greetings Horst

for the "k" version I see when the frequency counter and receive a signal >50kHz then the screen display becomes 816.XXX kHZ must divide 16, I see in hiland644 there is a component 74HCxxxx and switch jumper for 1/16 and it's not there for T7, if you try then you will see this on firmware version "k" and I've tried on version "m" it doesn't require 1/16 in frequency counter options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on October 02, 2021, 08:33:02 am
for the "k" version I see when the frequency counter and receive a signal >50kHz then the screen display becomes 816.XXX kHZ must divide 16, I see in hiland644 there is a component 74HCxxxx and switch jumper for 1/16 and it's not there for T7, if you try then you will see this on firmware version "k" and I've tried on version "m" it doesn't require 1/16 in frequency counter options.

Hello anwfeb,

You are absolutely right, the k-firmware for TC-1 and T7 (M644) can test all components, including crystals, but the frequency measurement is always from a 16 to 1 prescaler from which these devices (TC-1, T7) do not is available. This is a mistake!

If you want to measure frequencies, use the m-firmware, which works, but cannot measure crystals and the display flickers a little.

Greetings Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 02, 2021, 01:43:10 pm
Have you tried to enable WITH_FREQUENCY_DIVIDER in the Makefile (add: CFLAGS += -DWITH_FREQUENCY_DIVIDER)? That should add a menu to select the prescaler. Another way could be to tweak the frequency counter section in autoconf.h (set USE_FREQ to 1, and USE_HFREQ/USE_H_CRYSTAL/USE_L_CRYSTAL to 0). The k-firmware's setup of the basic and extended frequency counter options is a little bit awkward. It assumes that an ATmega644 based tester comes with the extended counter option (hence the default 16:1 prescaler).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on October 02, 2021, 04:14:07 pm
Hi Markus,

I just tested your suggested changes:

Neither "CFLAGS + = -DWITH_FREQUENCY_DIVIDER" alone,
still "set USE_FREQ to 1, and USE_HFREQ / USE_H_CRYSTAL / USE_L_CRYSTAL to 0" alone,
Both measures together still lead to the desired result.

As before, the first measurement is always correct, after that the multiplication by 16 is always carried out.

Even the old firmware versions all have this behavior, I never noticed it at the time because I probably always tested with lower frequencies <20 kHz.

Greetings Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 02, 2021, 07:59:38 pm
Thanks for testing! The change to the 16:1 prescaler is caused by the auto-ranging. If that happens despite USE_HFREQ being set to 0 then it might be a bug.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on October 02, 2021, 08:24:04 pm
...Besides the voltage divider there's also an offset, e.g. by a reverse polarity protection diode or the PNP power switch. The offset can be set via BAT_OUT (k-firmware: Makefile), or BAT_OFFSET (m-firmware: config.h). And the voltage divider can be changed too: BAT_NUMERATOR and BAT_DENOMINATOR (k-firmware: Makefile), or BAT_R1 and BAT_R2 (m-firmware: config.h).

Hi, My display shows overestimated voltage !?
In reality, for example 8.303V (battery 2S2P- 8.4V), and the display shows 8.45V ...
I measured the 10k / 3.3K divider - in reality I have 9.996k / 3.300k, i.e. I think it's okay.
To correct the readings in the "#define BAT_OFFSET 290" parameter (config.h, 1.44 m-firmware) do I need to correct the readings in "+" or "-"? The difference I have is ~ 0.15V (150mV), i.e. To register ~ 140 or ~ 430, is the amendment indicated in the mV in the same place?
Or is it better to correct in the divisor "BAT_R1 and BAT_R2"?
Will these corrections only affect the display or will they also affect other measurements?
---------------------------
Sorted it out like. I put 150 and the voltage more or less began to coincide. The measurements did not seem to have changed either.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 03, 2021, 03:12:38 am
Hi Markus,

I just tested your suggested changes:

Neither "CFLAGS + = -DWITH_FREQUENCY_DIVIDER" alone,
still "set USE_FREQ to 1, and USE_HFREQ / USE_H_CRYSTAL / USE_L_CRYSTAL to 0" alone,
Both measures together still lead to the desired result.

As before, the first measurement is always correct, after that the multiplication by 16 is always carried out.

Even the old firmware versions all have this behavior, I never noticed it at the time because I probably always tested with lower frequencies <20 kHz.

Greetings Horst

Yes, you are right. the first 1 - 2 seconds displays the correct result, then the next second displays the incorrect calculation (result*16) which is displayed on the screen. I didn't test if this bug exists on hiland644 because they have an extra component for frequency.

For the "m" version I have tested the frequency on the T7 and it works fine, no bugs in the frequency counter, but this version does not have a crystal check feature.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2021, 11:39:55 am
Will these corrections only affect the display or will they also affect other measurements?
---------------------------
Sorted it out like. I put 150 and the voltage more or less began to coincide. The measurements did not seem to have changed either.

The BAT_* values only affect the battery monitoring, i.e. the battery voltage displayed and the low-battery shutdown.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 03, 2021, 09:07:57 pm
In the HilandM644 an extended Frequency and crystal measurements carried out.
Hiland has two menu items for frequency measurements - up to 2 MHz and over 2 MHz. Both measurements are shown in the photo. So there are no problems with the software, you need to look at your diagram ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on October 03, 2021, 11:00:44 pm
Hiland has two menu items for frequency measurements - up to 2 MHz and over 2 MHz. Both measurements are shown in the photo. So there are no problems with the software, you need to look at your diagram ...

Hello Yuriy_K,

the HilandM644 does not cause any problems, it was only given as an example, since it uses an additional prescaler by 16 for the higher frequencies. This is not the case with the T7, but the k software always assumes an additional prescaler by 16 for the Atmega644 MCU and higher frequencies, which then leads to incorrect (multiplied by 16) results after the first measurement.

Due to my limited knowledge of English, I occasionally use the Google translator. This may have led to problems of understanding.

Greetings Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: ilcaccillo on October 03, 2021, 11:46:45 pm
Do you think it's possible or do you have the patience to explain that in other words so an ignorant (not knowledgeable) person like me could understand?

There's a chapter about the inductance measurement (also for the SamplingADC method) in Karl-Heinz' excellent documentation. And for the m-firmware you can find an explanation in inductance.c. It's boring physics. ;D Or see any suitable physics book/text/webpage about inductance.

Still I cant get around to understand how Inductance is measure without an AC signal being use.
I'm having problems understanding the concept
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on October 04, 2021, 01:48:15 am
Still I cant get around to understand how Inductance is measure without an AC signal being use. I'm having problems understanding the concept

Hello ilcaccillo

Extract from Karl-Heinz Kübbeler's documentation:

Transistor tester with AVR microcontroller Version 1.13k

Page 44

3.10 Measurement of coils

The normal measurement of the inductance is based on the measurement of the time constant of the
current grow. The detection limit is about 0.01mH, if the resistance of the coil is below 24Ω. For
bigger resistance values the resolution is only 0.1mH. If the resistance is above 2.1kΩ, this technique
can never be used to detect coils. The measurement results of this normal measurement is shown in
the second line (resistance and inductance). With the samplingADC method a resonant frequency
of coils can be detected with greater inductance values. If this effect is noticeable, the frequency and
the quality factor Q of the coil is shown additionally in line 3.
The method of resonant frequency measurement can also be used for the determination of the in-
ductance value, if a sufficient big capacitor mith know capacity value is connected parallel to a little
inductance (<2mH). With a parallel connected capacitor the normal measurement of inductance
can no more operate well. If the resonant frequency let assume a parallel connected capacitor, the
inductance of the normal measurement is not shown and the resistance value is shown in line 1. For
this resonant circuit the quality factor Q is also computed and shown behind the frequency value in
line 3. You can identify this type of measurement with the inductance value at the first position of
line 2, followed by the text “ if ” and the value of the assumed parallel capacity. The value of this
parallel capacitor can currently only be set with the calibration function (1-||- 3 10-30nF(L)).
For displays with only two lines, the content for the third line is shown time-delayed in line 2.

Greetings Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on October 04, 2021, 01:51:54 am
Excellent thread, I learned a lot and tried a lot. I upgraded a GM328A (1.8 color TFT) from 8MHz to 20MHz crystal and the 1.41m mod.  The menus are so much zippier with the faster clock.

I tried to do a similar upgrade to the really old near first M328 that uses a 1602 display. I swapped the 8MHz to 16MHz crystal and installed the "Rev804En(16MHz)" on a fresh 328PU chip. Everything seems to work -- except testing electrolytic caps.  If I have just turned it on after having it off a while, it usually will make it through testing a 10uf 50V 'lytic just fine.  A second press of the button and it makes it 2 to 6 "dots" scanning and then it immediately shuts down. If I power it back on it will keep crashing repeatedly until I put something other than a 'lytic to test.  All ceramic caps test fine.

I have tried it with Alkaline (9.2v), NiMH (9.6v) and LiIon (8.4v) 9V batteries all with the same "crash" results.   Before I put in the faster crystal I had tried the "Rev804En(8MHz)" file at 8MHz clock and it did not crash.  I also tried programming a different chip, same results. The same chips at 8MHz clock and 8Mhz program works fine.   (In fact, I programmed the chip for the 20MHz version for the GM328A mentioned at the top and it had no problems, so I doubt it's the ATMEL itself being able to run at 16 or 20).

What's causing the crash at 16?  Anyone see this on the older units?   (Pic below is from the archive site with all of the precompiled firmware zip's, but my tester looks the same)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 04, 2021, 08:28:48 am
bffargo,What type of +5V regulator is installed on your M328 clone? Show T1-T7 hardware test results at 16MHz?
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 04, 2021, 08:42:11 am
In the HilandM644 an extended Frequency and crystal measurements carried out.
Hiland has two menu items for frequency measurements - up to 2 MHz and over 2 MHz. Both measurements are shown in the photo. So there are no problems with the software, you need to look at your diagram ...


Can you try for a frequency above 50KHz, for example 55KHz, I started to find this problem when the generator freq number shows a number above 50KHz, and I have tried with 900Khz and it works no error, so to make sure please try again at 55KHz frequency - 100KHz if on hiland644 it works, then this bug is specifically for T7 upgrade atmega644 only, please provide check result information between 55-100KHz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 04, 2021, 10:42:51 am
Still I cant get around to understand how Inductance is measure without an AC signal being use.
I'm having problems understanding the concept

This might help: https://www.youtube.com/watch?v=WR6qVvnDnI4&list=PLX2gX-ftPVXUCWdUJJFtkXRKfhpzPR-f_&index=7 (https://www.youtube.com/watch?v=WR6qVvnDnI4&list=PLX2gX-ftPVXUCWdUJJFtkXRKfhpzPR-f_&index=7)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 04, 2021, 10:55:14 am
Can you try for a frequency above 50KHz, for example 55KHz,... please provide check result information between 55-100KHz.

See the results ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 04, 2021, 11:26:57 am
Can you try for a frequency above 50KHz, for example 55KHz,... please provide check result information between 55-100KHz.

See the results ...

Okay thanks Yuriy_K if it's like this then firmware "k" is not suitable for TC7 for Frequency Counter function, because TC7 does not have additional components that exist in hiland644 and the pdf schematic is written in version 1.13k
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 04, 2021, 12:23:55 pm
pdf schematic is written in version 1.13k
Show this pdf schematic or provide a link ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 04, 2021, 12:53:48 pm
pdf schematic is written in version 1.13k
Show this pdf schematic or provide a link ...

Page 25, Figure 2.16. Extended Transistor Tester circuit with ATmega644.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 04, 2021, 02:00:15 pm
My 3 homemade Ttesters are assembled according to this scheme ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 04, 2021, 02:09:00 pm
Okay thanks Yuriy_K if it's like this then firmware "k" is not suitable for TC7 for Frequency Counter function, because TC7 does not have additional components that exist in hiland644 and the pdf schematic is written in version 1.13k

I had a quick look at the issue. The precompiler directives for ATmega644 in GetFrequency.c are causing the 16:1 prescaler problem. When using an ATmega644 the "#if"s add the code for switching the external prescaler including auto-ranging. If the frequency is higher than a specific threshold the auto-ranging will enable the 16:1 prescaler. That's what you've noticed for higher frequencies, i.e. the first measurement is fine and after that the frequency is multiplied by 16. Adding another constant (e.g. USE_HFREQ) to the "#if" logic should fix the problem. I'll inform Karl-Heinz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 04, 2021, 03:08:35 pm
Okay thanks Yuriy_K if it's like this then firmware "k" is not suitable for TC7 for Frequency Counter function, because TC7 does not have additional components that exist in hiland644 and the pdf schematic is written in version 1.13k

I had a quick look at the issue. The precompiler directives for ATmega644 in GetFrequency.c are causing the 16:1 prescaler problem. When using an ATmega644 the "#if"s add the code for switching the external prescaler including auto-ranging. If the frequency is higher than a specific threshold the auto-ranging will enable the 16:1 prescaler. That's what you've noticed for higher frequencies, i.e. the first measurement is fine and after that the frequency is multiplied by 16. Adding another constant (e.g. USE_HFREQ) to the "#if" logic should fix the problem. I'll inform Karl-Heinz.

Thanks madries, I had previously reported to Karl-Heinz via email, but I don't know where the problem is coming from. Thanks for investigating this case and hopefully Karl-Heinz can fix the "k" version soon for the Frequency Counter fix especially for the T7 upgrade 644
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on October 05, 2021, 12:18:24 am
bffargo,What type of +5V regulator is installed on your M328 clone? Show T1-T7 hardware test results at 16MHz?

The test screens aren't numbered. I stitched them all together in order of display.  The regulator is a AMS1117.  I measured 4.97V out using a separate DMM.

Yes, I modified the version string before burning so I would remember it was the 16MHz one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 05, 2021, 06:58:04 am
The test screens aren't numbered. I stitched them all together in order of display. 
You showed the calibration results.I asked you to show the T1-T7 hardware test results. Read in the manual (chapter 5.5) how they are displayed. Also compare the test readings and performance of the latest firmware, which I have attached to the message.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on October 05, 2021, 03:24:27 pm
Thank you.  The new ZIP file you attached fixed the problem!  It no longer crashes.

Even so, here are the T1-T7 screens based on the new image in case this is of any use.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 05, 2021, 03:34:52 pm
It is highly desirable for you to pick up 3 accurate 470kOhm resistors. In the T3 test, a difference in readings of no more than 4-5 units is acceptable. You have this difference of 7 units. The T2 test looks more reasonable on your clone.Ideally,for the most reliable measurements, the readings in these tests should be close to 0 and the same.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on October 05, 2021, 04:51:55 pm
Thanks. I tested all of the resistors in circuit (ATMEL pulled) with a couple DMM's with the following results.   So I should just pull a trio of resistors as close to 470K as possible and between each other and replace R2/R4/R6 ?  Any of the others below look far enough off to be of a concern?

Note the issue with R8 that comes off the 9V input to the transistor. It's an order of magnitude off; accd to the schematic posted here; or the schematic is wrong: https://disk.yandex.ru/d/yW8xa5NJgUo5z/M328/Schematic%20diagram/M328.JPG

Code: [Select]
        DMM1 DMM2
R1 680 s/b 680 706.8
R2 474K s/b 470K 474.6K
R3 680 s/b 680 706.2
R4 476K s/b 470K 475.8K
R5 680 s/b 680 706.2
R6 473K s/b 470K 473.8K

R7 8.7K s/b 10K 9.99K
R8 3.29K s/b 33K ??? 3.317K
R9 3.31K s/b 3.3K 3.331K
R10 27.1K s/b 27K 27.16K
R11 99K s/b 100K 99.2K
R12 9.98K s/b 10K 9.999K
R13 3.28K s/b 3.3K 3.324K
R14 558 s/b 560 584.0
R15 26.9K s/b 27K 26.95K
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 05, 2021, 05:12:36 pm
  So I should just pull a trio of resistors as close to 470K as possible and between each other and replace R2/R4/R6 ?
Yes!
Note the issue with R8 that comes off the 9V input to the transistor. It's an order of magnitude off; accd to the schematic posted here; or the schematic is wrong:
The schematic is correct,probably a mistake on the circuit board. Your problems with the tester malfunctioning and disconnecting it may be related to this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on October 05, 2021, 08:56:07 pm
All 3 resistors are now swapped. Here are the results (only showing the screens that were different than the last batch I uploaded).  Some of them flipped between values during the test, I only included the last values shown per test before the next test started.

I think the 3.3K vs. 33K resistor most impacted the raw voltage reading on the battery, it reported closer to actual once that was swapped out. The regulator was still outputting around 5V either way.

Thanks again. Let me know if there are any other concerns I should look into to make it better.  Otherwise the new firmware definitely helped with the crashing first.

Also, where did the new Rev897 zip come from? I didn't see it on the yandex site that was last updated with Rev804 back in May.  Was that just a one off build off the current branch you did for me? If so, thank you!

Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 06, 2021, 06:26:48 am
Hi.. how do I adjust the value of the measurement result? I'm using firmware 1.13k and the capacitor measurement results have to increase 0.5pf while the resistor measurement results have to reduce 0.05 ohm

Sample case,
I measure Capacitor 1pf, then the measurement result is 0.51pf

Sample case,
I measured a 0.33 ohm resistor, then the measurement result is 0.38 ohm.

How do I adjust the measure value in code? Calibration has been performed but does not solve the problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 06, 2021, 07:33:19 am
Was that just a one off build off the current branch you did for me?
Yes, this is a special version for your clone! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 06, 2021, 02:47:39 pm
Hi.. how do I adjust the value of the measurement result? I'm using firmware 1.13k and the capacitor measurement results have to increase 0.5pf while the resistor measurement results have to reduce 0.05 ohm

If you really want to add/subtract those values you can modify the firmware, e.g. the output function. However, for those low values it doesn't make much sense to go to the extreme because the Transistortester isn't a precision instrument.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 06, 2021, 06:10:42 pm
Hi.. how do I adjust the value of the measurement result? I'm using firmware 1.13k and the capacitor measurement results have to increase 0.5pf while the resistor measurement results have to reduce 0.05 ohm

Sample case,
I measure Capacitor 1pf, then the measurement result is 0.51pf

Sample case,
I measured a 0.33 ohm resistor, then the measurement result is 0.38 ohm.

How do I adjust the measure value in code? Calibration has been performed but does not solve the problem.
The measurement accuracy depends on many factors, voltage stability, input wiring, measurement frequencies, and so on. What true meaning are you targeting?
Here is an example of measuring capacitors using different methods on different devices. As you can see, the readings of the devices do not always correspond to the inscriptions on the capacitors. A similar example with resistance measurement, but measurements are made with direct current and the readings differ slightly ...

Show examples of your measurements ...

Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 07, 2021, 12:33:09 am
Hi.. how do I adjust the value of the measurement result? I'm using firmware 1.13k and the capacitor measurement results have to increase 0.5pf while the resistor measurement results have to reduce 0.05 ohm

If you really want to add/subtract those values you can modify the firmware, e.g. the output function. However, for those low values it doesn't make much sense to go to the extreme because the Transistortester isn't a precision instrument.

can you help me to adjust the output so that the measurement results can match?
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 07, 2021, 12:40:58 am
Hi.. how do I adjust the value of the measurement result? I'm using firmware 1.13k and the capacitor measurement results have to increase 0.5pf while the resistor measurement results have to reduce 0.05 ohm

Sample case,
I measure Capacitor 1pf, then the measurement result is 0.51pf

Sample case,
I measured a 0.33 ohm resistor, then the measurement result is 0.38 ohm.

How do I adjust the measure value in code? Calibration has been performed but does not solve the problem.
The measurement accuracy depends on many factors, voltage stability, input wiring, measurement frequencies, and so on. What true meaning are you targeting?
Here is an example of measuring capacitors using different methods on different devices. As you can see, the readings of the devices do not always correspond to the inscriptions on the capacitors. A similar example with resistance measurement, but measurements are made with direct current and the readings differ slightly ...

Show examples of your measurements ...

for the measurement I want is how it approximates exactly, it doesn't have to be right in the final digits of the 3rd digit but if 5.6pf looks on the screen is 4.8pf it means I will assume this capacitor is 4.7pf if there is no writing on the physical body of the capacitor
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 07, 2021, 12:41:45 am
or, if the resistor is 0.33 ohm, if on the physical body there is no color then I will assume the resistor is 0.39 ohm
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 07, 2021, 01:50:59 am
In your photo, I do not see a way to connect the part to be measured with the measurement contacts. It is impossible to understand what the Ttester readings are in the absence of the measured part.
In my photos, I specifically show the way to connect the part to be measured ...

Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 07, 2021, 02:27:36 am
In your photo, I do not see a way to connect the part to be measured with the measurement contacts. It is impossible to understand what the Ttester readings are in the absence of the measured part.
In my photos, I specifically show the way to connect the part to be measured ...

I connected directly to the ZIF socket because the photo with the app collage was cut off the bottom of the ZIF, the component was connected directly without a probe cable, and when without a component the value was 0.01 after calibration (not -0.5) I understood the calibration function so that the value without components was 0.00 or close to 0.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 07, 2021, 02:44:28 pm
anwfeb,show the measurement results of the same capacitors, but insert the part into pins 1-2 and 2-3.
I would also like to see the T1-T7 hardware test results on your clone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 07, 2021, 03:05:52 pm
anwfeb,show the measurement results of the same capacitors, but insert the part into pins 1-2 and 2-3.
I would also like to see the T1-T7 hardware test results on your clone.

Hi.. indman, I have done some experiments, the last time I saw a difference in the ZIF socket, when I calibrated with the ZIF Locked position, the 1pf Capacitor measuring value is now 1.2x pf. but if I calibrate with ZIF socket unlocked, the result of measuring 1pf capacitor is 0.5x pf. I already know that different measurements when calibrating with ZIF socket locked/unlocked make different measurement results, I don't know if this is the same for other devices? or my ZIF socket is broken? but I have realized that it affects the difference in the measurement results. however, for resistors measuring in 0.22 ohm still shows 0.28-0.31 ohm, I haven't figured out what the problem is.

i have researched further for TL431 at the foot of the PA3 pin I measure the voltage is not up to 2.5v but only get 2.48v is this a problem?

T1-T7 test results will follow soon I will inform

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 07, 2021, 03:22:45 pm
I already know that different measurements when calibrating with ZIF socket locked/unlocked make different measurement results, I don't know if this is the same for other devices?
Yes, this is a prerequisite for the correct calibration of all devices if you want to obtain reliable results with small capacitance values. As open contacts ZIF introduce an additional error during calibration.

i have researched further for TL431 at the foot of the PA3 pin I measure the voltage is not up to 2.5v but only get 2.48v is this a problem?
No.Install a quality MCP1702 stabilizer in your clone and the external TL431 can be removed from the circuit altogether. Firmware does not need to be changed, just change the 2.2kOhm resistor to 47Kohm.
Also select the same pairs of 680Ohm,470kOhm measuring resistors. Refer to the T1-T7 test results. This is 99% likely to help you solve your resistor measurement problem, although even now your error is no more than a reasonable value for TESTER.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 07, 2021, 03:46:07 pm
No.Install a quality MCP1702 stabilizer in your clone and the external TL431 can be removed from the circuit altogether. Firmware does not need to be changed, just change the 2.2kOhm resistor to 47Kohm.
Also select the same pairs of 680Ohm,470kOhm measuring resistors. Refer to the T1-T7 test results. This is 99% likely to help you solve your resistor measurement problem, although even now your error is no more than a reasonable value for TESTER.

yes, I'll try again, it's true this is still within the reasonable threshold of measurement, but I just want to improve for a more precise measurement then that is the best.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 07, 2021, 05:35:58 pm
Good news regarding the frequency counter issue with the 16:1 prescaler and ATmega644. Karl-Heinz has added a configuration switch (NO_FREQUENCY_SWITCH=1) to disable the external prescaler. Please see https://github.com/kubi48/TransistorTester-source for the latest version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 07, 2021, 05:42:33 pm
Good news regarding the frequency counter issue with the 16:1 prescaler and ATmega644. Karl-Heinz has added a configuration switch (NO_FREQUENCY_SWITCH=1) to disable the external prescaler. Please see https://github.com/kubi48/TransistorTester-source for the latest version.

thanks info madries, I'll try with the new firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 08, 2021, 05:07:27 am
anwfeb,show the measurement results of the same capacitors, but insert the part into pins 1-2 and 2-3.
I would also like to see the T1-T7 hardware test results on your clone.

I noticed T6 RH+ changed 4x in 4 seconds,
first second 0 0 0
2nd second -3 0 0
3rd second -2 0 0
fourth second -2 0 -1
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 08, 2021, 06:51:04 am
Why is there such a difference in the resistance of the closed contacts of 0.18-0.27?! This resistance should be approximately the same, check the reliability of the contacts of the ZIF panel. Also pick up the 680Ohm resistors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 08, 2021, 07:21:18 am
Why is there such a difference in the resistance of the closed contacts of 0.18-0.27?! This resistance should be approximately the same, check the reliability of the contacts of the ZIF panel. Also pick up the 680Ohm resistors.

I have check ZIF, and here are the test results now
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 08, 2021, 07:24:55 am
0.24-0.34!!!0.1 Оhm distinction!!! Check the measurement results of the low resistor, e.g. 0.33 Ohm, on the different pins 1-2,2-3,1-3.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 08, 2021, 07:38:17 am
0.24-0.34!!!0.1 Оhm distinction!!! Check the measurement results of the low resistor, e.g. 0.33 Ohm, on the different pins 1-2,2-3,1-3.

Please check
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 08, 2021, 07:44:03 am
Yesterday you showed the same resistors, but the results today are different and more reliable. What's changed since yesterday? ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 08, 2021, 08:03:53 am
Yesterday you showed the same resistors, but the results today are different and more reliable. What's changed since yesterday? ;)

I don't know what changes break the measurement value,
now i use "k" firmware with freq counter fix (not use yesterday firmware) then i fix 5V LDO now my LDO shows 5.04V as you said i have to replace better LDO.

however, the resistor measurement after 1 hour I repeat the measurement without calibration then, the result will change. every low resistor measurement I have to calibrate, or I have to do a 3pin jumper probe but when there is a request for selftest mode... ? I looked at it and saw the results of the short probe 0.00 0.00 so I did a resistor check and the results were appropriate. but if I do not calibrate and see the 3 pin probe jumper then the result is 0.07 0.00 this will damage the current value of the measurement. can you find out where this error lies?

the change in the value of short check pin 123 occurs after a few minutes or after a few hours, so I have to calibrate again to get the result 0.00 - 0.00, as if eeprom didn't save the last calibration result.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 08, 2021, 08:14:00 am
The first thing you need to do, as I wrote before, is to provide a stable and noise-free power supply to the processor. The word stable should be understood not only as a constant value of output voltage +5.000 V, but also the ability of the regulator to respond very quickly to changes in current and short-term pulses of the load. All this is achieved if you install a QUALITY! regulator, as well as apply the same QUALITY!  filter capacitors to the input and output. Only when these conditions are met can you hope to get reliable readings when testing different parts. Is that clear?
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on October 08, 2021, 08:30:32 am
The first thing you need to do, as I wrote before, is to provide a stable and noise-free power supply to the processor. The word stable should be understood not only as a constant value of output voltage +5.000 V, but also the ability of the regulator to respond very quickly to changes in current and short-term pulses of the load. All this is achieved if you install a QUALITY! regulator, as well as apply the same QUALITY!  filter capacitors to the input and output. Only when these conditions are met can you hope to get reliable readings when testing different parts. Is that clear?

Yes, I will try again later to find another LDO that can stabilize conditions where there is a change or the load short-term pulses of the remains at 5.00v
I understand how important the regulator is to get the right and accurate measurement value
Title: Re: $20 LCR ESR Transistor checker project
Post by: CatalinaWOW on October 08, 2021, 04:49:45 pm
It is kind of funny watching the change in attitude over the course of this thread.  Back when it started there was a sense of wonder that an inexpensive device could provide a variety of usable measurements.  Over time that has morphed into outrage that this same device doesn't provide instrument grade results.  In a sense it is recapitulating the history of test equipment.  Initially crude measurements refined over time through attention to detail and clever engineering.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 08, 2021, 05:14:32 pm
I Initially crude measurements refined over time through attention to detail and clever engineering.
Not only that, software and its improvement by the authors plays a big role. After all, the circuitry of this device is almost unchanged (not much) ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 08, 2021, 05:29:00 pm
And some don't understand that the Chinese clone manufacturers use whatever parts are on sale in Shenzhen. If you're lucky your tester is spot on. But it could be also a few percent off. With the right parts you can get about 1% accuracy for a few measurements which is the limit of what is possible with the current design. The Transistortester was never meant to be anything more than a versatile tool. Karl-Heinz and I are sometimes amazed what can be achieved with that simple circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on October 08, 2021, 05:54:08 pm
Karl-Heinz and I are sometimes amazed what can be achieved with that simple circuit.
Correction: there are allot more people that are amazed and talk about it, myself included! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 09, 2021, 11:49:17 pm
Dears,

Please give me a hand with my TC-1: I replaced U4 with a circuit composed of a veroboard and 2N3906, 2N3904, 3K3, 24K, 1N4148 (the small parts that I had at hand) plus enameled wire. Then I soldered a reversed SPI and flashed an 1.44m, make'd following the Clones file. Note: for the ST7735 I disabled the SPI_hardware (as I've read the pin assignment of this doesn't allow that), and added the spi bitbang configuration which was not on that section of the config_644.h. My flash size was 99.7% of the max.

At rest, it draws 4uA (as expected), and U4_P1 is Vbatt (3.8V), the rest 0V. If I short-press the button, the screen goes white for a second, then goes totally black with the backlight still on, drawing around 200mA, the button no longer responds and I have to remove the battery to power it off. If I long-press the button, the screen remains white for two or three seconds and then the same. When on, I measure close to 5V on the U4 pads.

Has anybody had similar difficulties?

BTW: Just in case, I'm following a schematic that sets P7(PD1) low when pressing the button, opposite to an old message in this thread during the early stages of support for this unit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 10, 2021, 07:37:46 am
Try pouring this firmware into the processor for a test
https://yadi.sk/d/yW8xa5NJgUo5z/LCR%20%D0%A2%D0%A1-1/Firmware/Markus%20Reschke/English/16MHz
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 10, 2021, 11:30:51 am
Spasiba. Now I know my error(s) was in the firmware settings (and not the hardware mod). Your 1.34m works, although the offsets are wrong (cutted letters at the top and the right, and garbage at the bottom). I'll compare the provided config.h and config644.h with mines to see how to fix my 1.44m.

Edit: Fixed my 1.44m. Thanks again, indman  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on October 12, 2021, 08:32:38 pm
Added to the menu - Voltage.....

Yury_K, do not tell me in which file what to fix, so that some colors can be changed?
in particular, I would like to make the colors of contacts 1,2,3 cyan, green, magenta.
I compiled the firmware from the "ST7735" folder (according to your Make-file, guided by this message), but it turned out I can only change the standard - the background color and the text color ...
Maybe where you need to register SEMI_ST7735 instead of ST7735? I can't figure out which files and what to fix yet ... I have a BGR 7735 display. Maybe at least just the names of the files, tell me which ones to dig (only those where the colors can be edited)?
Or can I write the colors of the probes in the Make-file? (although I tried to add it like this, but there is no result ... although everything was compiled without errors) ... In firmware 1.44m it is easier there (there is a file colors.h))))
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 12, 2021, 11:17:08 pm
As you refer, on the m-firmware there is the colors.h file, there you will find the RGB color definitions for the colors for the particular display you're about to use (if your display is BGR instead, I think the conversion is handled internally), followed by a section where you assign the particular color you want for an specific item on the screen.

You also have to uncomment the UI_PROBE_COLORS on the config.h for the zocket_terminals / cable_leads to be colored.

I attach some samples of this on 1.44m for a ST7735.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 13, 2021, 02:57:40 am
Yury_K, do not tell me in which file what to fix, so that some colors can be changed?
 ... In firmware 1.44m it is easier there (there is a file colors.h))))
Want to change colors? Try it out on m firmware. If possible, transfer his approach to the sources from Karl-Heinz. It took me over two years to do this. There is not enough room on the 328 processor without removing some of the Karl-Heinz approaches to colors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on October 13, 2021, 07:55:58 am
...I attach some samples of this on 1.44m for a ST7735...
Yes, at 1.44m I know all this and there are no problems, everything works out there )))

...Want to change colors? Try it out on m firmware. If possible, transfer his approach to the sources from Karl-Heinz. It took me over two years to do this. There is not enough room on the 328 processor without removing some of the Karl-Heinz approaches to colors.
It's clear. It is really difficult to deal with colors on k-firmware.
I looked more closely at the instructions, it says directly that at the moment the chromaticity is not used ... only the general background color and the text color can be changed.

Thanks for answers. In general, the situation has cleared up)))
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 14, 2021, 10:00:46 am
Question for madires: can the measuring range of capacitors be extended to supercapacitors?

I think it would be useful to be able to check the value of supercapacitors, even with lower accuracy, like 5% - 10%.

For example, I want to know if a supercapacitor of 0.33F/5.5V is still good, ie if it has a value close to the one inscribed on it. I'm not necessarily interested in ESR or power leakage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 14, 2021, 01:34:20 pm
Sorry, supercaps can't be checked with the Transistortester because they require a special test setup with a constant current discharge. Neither can a typical LCR meter, e.g. DE-5000, measure them.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 14, 2021, 04:44:06 pm
So a measurement solution would be a separate assembly, which measures the charging time with a constant current, a process controlled by an MCU.

Yeah, I'll get to work.

OK, thanks for the quick response and for the idea.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 14, 2021, 05:42:09 pm
The steps for measuring the capacitance of a supercap are:
- charge the supercap
- start discharging the supercap via a constant current (I)
- a little bit later: measure the cap's voltage (V1) and start counting seconds (T1)
- some time later: take a second voltage measurement (V2) and get the time elapsed since the first measurement (T2 - T1)
- C = I (T2 - T1) / (V1 - V2)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on October 14, 2021, 09:00:17 pm
Hello.
There is no "transistor" item in the menu (firmware 1.44m) ... it only measures if you initially insert and apply power.
If you work constantly through the "Menu" and you need to measure the transistor, then you have to press "Exit", then again after the inscription "Done!" (she's also annoying, it's better to have a blank screen :)) ... or to turn on / off the power, which is not very convenient.
Is it possible to add a separate item?Something like an "RCL-monitor" ... like a "TD-monitor" (Transistor-Diode)? Or just a "Transistor" (like in firmware 1.13k for example) ...
Not fundamentally, of course, but for convenience...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 15, 2021, 03:36:10 am
Going back to the colors subject, I have a question or feature request:
Would it be possible to reverse the color of some numbers, i.e. color squares with white numbers for the symbols and titles?
I think for some screens&colors combinations that would be easier to read.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 15, 2021, 05:36:04 am
Feliciano, all this can be made multicolored and inverse, but take into account that this will increase the memory consumption for the firmware, which is already catastrophically not enough for ATmega328(324)!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 15, 2021, 10:22:27 am
There is no "transistor" item in the menu (firmware 1.44m) ... it only measures if you initially insert and apply power.
If you work constantly through the "Menu" and you need to measure the transistor, then you have to press "Exit", then again after the inscription "Done!" (she's also annoying, it's better to have a blank screen :)) ... or to turn on / off the power, which is not very convenient.
Is it possible to add a separate item?Something like an "RCL-monitor" ... like a "TD-monitor" (Transistor-Diode)? Or just a "Transistor" (like in firmware 1.13k for example) ...

Should be possible. But it would be something for an ATmega with 64kB flash.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 15, 2021, 10:44:21 am
Feliciano, all this can be made multicolored and inverse, but take into account that this will increase the memory consumption for the firmware, which is already catastrophically not enough for ATmega328(324)!
That's what I was afraid of. Anyways I think it would be a good option for 64KB units.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 15, 2021, 11:00:38 am
Yes,for devices with 64kb or more memory there is an opportunity to add color coloring and big symbols, but then largely lost the versatility of basic firmware, which can not give up our esteemed authors. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on October 15, 2021, 12:45:42 pm
Should be possible. But it would be something for an ATmega with 64kB flash.
Yes, memory problems are serious, alas.
But on the other hand, there is an option to disable unused menu items.
For example, I have never used (10-PWM, generator, frequency counter) at all ... and if you suddenly need it sometime, then it's a matter of 15 minutes to recompile the firmware by replacing something ...
It's just good when there is a large selection of items and the user can rebuild according to his needs (taking into account the memory of course) :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 15, 2021, 01:54:44 pm
I'll put it on the to-do list (low priority). BTW, I've started working on the ring tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 15, 2021, 05:23:00 pm
if you suddenly need it sometime, then it's a matter of 15 minutes to recompile the firmware by replacing something ...
Yes, because memory limitations everyone should prioritize which functions use often and which functions are seldom used. To recompile it's an option, other is to have two (or three) devices ready-made for different purposes.

I'll put it on the to-do list (low priority).
Good (no rush indeed). I was thinking one approach to keep memory consumption under control could be to tweak the font file. For instance, AFAIK in English the letters Ä,Ö,Ü,ä,ö,ü are not used. That could give us 6 places where to put the reversed numbers. Other special characters that could be revised are the three quotes on the font file, i.e. ´,', " and the ~ (which I don't recall whether it's currently used by the firmware), as well as the round, square and curly brackets. I attach a font sample to help you ponder whether this approach could be implemented (and of benefit). Of course the other apprach would it be to set the background for a tile in one color and the foreground in other. I don't know which method would use more flash, so I leave it to the expert (madires).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on October 16, 2021, 06:08:02 pm
...BTW, I've started working on the ring tester.

"ring tester"(oh, this google ...) Those. I understand correctly that you are planning to make a function to ring out radio components?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 16, 2021, 06:35:05 pm
I was thinking one approach to keep memory consumption under control could be to tweak the font file. For instance, AFAIK in English the letters Ä,Ö,Ü,ä,ö,ü are not used. That could give us 6 places where to put the reversed numbers. Other special characters that could be revised are the three quotes on the font file, i.e. ´,', " and the ~ (which I don't recall whether it's currently used by the firmware), as well as the round, square and curly brackets.

Of course you can remove unused characters and lower the flash usage, but it will become a nightmare to maintain font files specific for each language.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 16, 2021, 06:39:54 pm
"ring tester"(oh, this google ...) Those. I understand correctly that you are planning to make a function to ring out radio components?

Also called LOPT or FBT tester. It's meant to check chokes and transformers for shorts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 16, 2021, 06:45:18 pm
"ring tester"(oh, this google ...) Those. I understand correctly that you are planning to make a function to ring out radio components?
And it's not a bad idea to add an audible continuity check and sound notification of the p-n junction of diodes and transistors? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 17, 2021, 12:06:30 am
Of course you can remove unused characters and lower the flash usage, but it will become a nightmare to maintain font files specific for each language.
Yes, I was thinking on tweaking only the English font, since this would be a visual aid (for older eyes) more than anything else. That would be an addon font, shall you determine that would be the best approach. I could help creating/revising that font map.

And as I said, other option would it be a traditional approach of drawing color backgrounds and foregrounds. But as you know C much better than me, I leave it to your kind consideration when you take the time to study this case.

Other thought for improving readability on 160x128 displays would it be to have a tad bigger font -with the same 32B/tile- like 12x16. What do you think?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 17, 2021, 10:51:17 am
And it's not a bad idea to add an audible continuity check and sound notification of the p-n junction of diodes and transistors? :)

Adding a buzzer is easy. But doing a proper continuity check in software isn't.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 17, 2021, 11:05:43 am
But doing a proper continuity check in software isn't.
You can use a simple -3 level option that evaluates the ADC on the input:
1.Below 0.1V - continuous signal
2.Range 0.1V-0.7V p-n junction(single short signal)
3.Above 0.7V - no signal
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 17, 2021, 11:57:01 am
Yes, I was thinking on tweaking only the English font, since this would be a visual aid (for older eyes) more than anything else. That would be an addon font, shall you determine that would be the best approach. I could help creating/revising that font map.

And as I said, other option would it be a traditional approach of drawing color backgrounds and foregrounds. But as you know C much better than me, I leave it to your kind consideration when you take the time to study this case.

Other thought for improving readability on 160x128 displays would it be to have a tad bigger font -with the same 32B/tile- like 12x16. What do you think?

Adding reversed characters to the font (doesn't matter if in the same font file or if it's an additional one) would add another layer of complexity to everything related. Using slightly larger characters for probe numbers would make the layout framework more complex. And we also have to deal with page organized displays. Simply reversing foreground and background colors requires additional lines at one or two sides of each character, as fonts include a fixed character spacing scheme. Again, many transistortesters have page organized displays. Unfortunately there's no easy way without increasing the firmware size significantly and maybe rendering a lot of testers obsolete. For an easy to read display I'd recommend a large ILI9341/2 based LCD (up to 3.2") and using the 16x26 font.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 17, 2021, 12:05:51 pm
You can use a simple -3 level option that evaluates the ADC on the input:
1.Below 0.1V - continuous signal
2.Range 0.1V-0.7V p-n junction(single short signal)
3.Above 0.7V - no signal

I see. I'll put it on the to-do list.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 17, 2021, 12:12:55 pm
I see. I'll put it on the to-do list.
I'm sorry we're not letting you get bored and relaxed with our new ideas. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 17, 2021, 12:20:45 pm
Poor me! ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 17, 2021, 05:06:33 pm
Once more, thanks for all your support.

As reversing some colors looks too complicated, I think I would create a bold or semibold 10x16, or try to use a 12x16 font for the ST7335 (some reason for not being an option on the current config644.h?).

BTW: I looked into the 12x16_hf and spotted 3 errors (flipped first diode, wrong Ä, and the Ü=ü) (iirc, somebody already reported the diode error). If that font is viable, I'll look how to fix those characters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 17, 2021, 06:54:31 pm
The 12x16_hf (also 2x16_iso8859-2_hf) isn't used yet because it allows only 13 characters per line on a 160 pixel wide display. If you want to use it with an ST7735 you need to add '#include "font_12x16_hf.h"' to the driver and set FONT_12X16_HF in the display configuration.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on October 18, 2021, 01:23:47 am
The san-serif font just posted above is great. It's crisp and clear. The ones with thin edges to then accommodate serifs are much harder to read. Standard 8-bit block fonts from the 80's are much easier.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 18, 2021, 11:06:01 am
Since we're talking about fonts, there's an option in the m-firmware to display the whole font. Enable SW_FONT_TEST in config.h and you'll get a menu item "Font".
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 18, 2021, 04:40:46 pm
The fonts bitmaps I've been attaching recently have been rendered on my computer from the actual font file (simulating a display under a ~5x zoom), to ponder how it would look, and spot for little bugs and/or things to improve before compile/flashing it.

If you guys already have the font loaded to your device, you can use the optional Font menu on the m-firmware, or it can be shown at the end of the show data on the k-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: robca on October 18, 2021, 05:28:08 pm
You can use a simple -3 level option that evaluates the ADC on the input:
1.Below 0.1V - continuous signal
2.Range 0.1V-0.7V p-n junction(single short signal)
3.Above 0.7V - no signal

I see. I'll put it on the to-do list.
Not sure if it's possible with the existing circuit, but this is an interesting implementation of a continuity tester using an ATtiny85 http://www.technoblogy.com/show?1YON (http://www.technoblogy.com/show?1YON)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 18, 2021, 05:42:50 pm
Not sure if it's possible with the existing circuit, but this is an interesting implementation of a continuity tester using an ATtiny85 http://www.technoblogy.com/show?1YON (http://www.technoblogy.com/show?1YON)
There are enough devices of this kind on the internet, simple and more complicated, on Arduino, ATiny, Pic controllers. But it will be very goot if autors adapt this function to the tester. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 19, 2021, 11:51:17 am
If we keep talking about additional functions for the tester, it might be interesting to add a logic probe function with selection, from the menu, for TTL / CMOS level.

In the case of CMOS it would be good to be able to select the supply voltage in the range 3.3V - 15V.

The measuring input can be for external voltage.

It would not require hardware changes, only software.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 19, 2021, 02:09:35 pm
If your tester has the 10:1 voltage divider for the Zener check but no boost converter we could use that input. The ratio of the voltage divider isn't ideal for 18 V or so, but it should work. Some testers have that 10:1 voltage divider for measuring an external voltage up to 50 V. Another idea is a temporary voltage divider at the probes, but I don't like that (some silly mistake could kill the ATmega easily). So I'd prefer an unused ADC pin with an optimal voltage divider and some simple and robust input protection.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 20, 2021, 12:23:26 pm
Quick question: the special B-like character on the font file, is supposed to be the greek beta (β) or the german esstsett (ß)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 20, 2021, 12:53:33 pm
The one just after the upper case umlauts is the ß (Eszett, or sharp s).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 20, 2021, 01:17:35 pm
I have three testers (clones). In order of purchase: LCR-T4, M328 KIT COLOR (AY-AT) and LCR TC-1 (with ATmega324).

For the M328 KIT COLOR (AY-AT) I was thinking of adding an 80k resistor (1: 5 ratio) for the additional logic tester input, using the same PC3 port and 20k ground resistor, as for the voltmeter function.

From SRV05-4 only 3 protection circuits are used; the fourth can be used to protect PC3.

For me, hardware modification is not a problem, but software modification is. I am a beginner in programming. madires can you please help me, tell me what exactly I should add / modify in the software?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 20, 2021, 02:01:15 pm
To just measure the voltage:
- Enable HW_ZENER, ZENER_DIVIDER_CUSTOM and ZENER_UNSWITCHED.
- Set ZENER_R1 and ZENER_R2
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 20, 2021, 06:54:18 pm
Thanks for the reply madires, but I think I did not express myself intelligibly enough.

My intention is to introduce a new "logic tester" function, with "TTL" and "Vcc - CMOS" submenu options, where Vcc can be selected in the 3.3V - 15V range.
"L" or "H" or "Indefinite or HiZ" or "Pulse" should be displayed on the screen, as the voltage value on the ADDITIONAL pin "Test logic input" falls within the logic levels:

For TTL (Vcc = 5V)
- L => 0V to 0.8V
- H => 2V to 5V
- Undefined / HiZ => 0.8V up to 2V

For CMOS (Vcc = 3.3V up to 15V)
- L => 0V up to 1/3*Vcc
- H => 2/3*Vcc to Vcc
- Undefined / HiZ => 1/3*Vcc to 2/3*Vcc

Can I make the necessary changes / additions, considering that I am a beginner in programming?
If so, I would need some guidance on how to intervene in the script.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 20, 2021, 07:30:37 pm
I think it would better to wait until I have the time to add the logic probe function, because it would take more time to explain all the details.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on October 22, 2021, 08:30:45 pm
I picked up a LCR-T4: The 128x64 LCD arrived broken on the top left overhang. The top half of the display is dead but bottom works perfectly.

I was curious if there was any way to get either alternate firmware to work on this making it think it was a 128x32 display forcing everything into the lower half (or having it treat it like a 1602 in a way?) as it would be fully usable then.  Now: Diodes, Transistors = cut off, caps and inductors mostly okay.

Screens cost more than a new T4; no sense to try to replace the screen. I was originally going to mod it to 16MHz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 22, 2021, 10:36:15 pm
Should be an ST7565 based display which is easy to get. To just use the working half of the display you would have to modify the display driver in the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on October 23, 2021, 06:41:05 am
@bffargo:

In my experience, an LCD display that has been broken in one corner will be completely damaged in a relatively short time, on the order of months.
You better replace it with another graphic display that you have at hand - anyway I understood that you will have to change its software, if you want to change the quartz with a 16MHz one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 23, 2021, 07:51:30 am
In my experience, an LCD display that has been broken in one corner will be completely damaged in a relatively short time, on the order of months.
I concurr.
Screens cost more than a new T4; no sense to try to replace the screen.
Then I would buy another component tester with a 328p, and keep the one you have for spares.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on October 23, 2021, 08:20:22 pm
...Screens cost more than a new T4; no sense to try to replace the screen.
Maybe a 2x16 LCD display would be easier and cheaper to obtain?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 30, 2021, 12:53:26 pm
FWIW here's a proposal of a sample reversed_numbers-font I was talking about, that could be used on graphical c_testers -with enough free flash- for drawing tiled_pin_numbers next to the symbols. (note: as discussed on the previous page, this is a low-priority request).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 31, 2021, 07:22:29 pm
The best solution would be to add the three inversed digits to each font, use ASCII values for control characters (e.g. 8-10) for the mapping and simply change the base character in Display_ProbeNumber(). That way the reversed digits would be also used for other pinouts, not just for the semiconductor symbols. And, of course, as an option.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on November 01, 2021, 01:16:50 am
Sounds good to me, but you know best, so I leave it to you (as an option for equipments with enough free flash, and when you have some spare time).
Shall you want me modify some other font let me know.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 01, 2021, 11:01:15 am
If you like you can do the three inversed digits for all other fonts (not for HD44780 and ST7036).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on November 01, 2021, 01:03:16 pm
But as you told me for compatibility reasons we rather no reasign special characters for this, do you want me to insert some tile_numbers bitmaps without code (to be called by some special method you'll design), or you want an additional font bitmap file (with the three numbers each) and then you select one fontset or the other according to what is going to be draw?

If we go with the later, on the main code we select font_x_hf.h for drawing measured values, and when we're about to write the first line icon or the font symbols we select font_x_inv_hf.h, like the .h I attached on my last post. (note: atm I have only have developed how to render horizontal_flipped fonts).

Please confirm.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 01, 2021, 01:38:06 pm
Please do them as in your example above. I'll add them to the normal font files afterwards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 01, 2021, 02:20:06 pm
About a year ago I also had an idea to make an interface similar to the Chinese version of LCR-T4 firmware. I made new graphics for the elements as well as inverted pin numbers for the 8x8 font and m-firmware. But later I was convinced that such interface looks good, but it takes a lot of memory space in the 328th ATMega and for the basic functionality is not enough space. I gave up on that option. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on November 01, 2021, 04:45:16 pm
I see. Which font did you use, 8x8? If you still have the bitmaps, and if you are willing to share it, it will save us some time for this test, and it would be appreciated.

On the other hand, do you recall how much extra memory took your approach?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 01, 2021, 04:47:47 pm
No, I've put that idea aside for the future and I'm not going to publish it just yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on November 01, 2021, 06:26:21 pm
Random thought - Rather than take space making full numerals, could you use 1,2,3 pixels arranged to indicate pin number instead? Something like this using one pixel per dot, or could be expanded to 2x2 pixels per dot.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on November 01, 2021, 07:06:16 pm
Well, we could reduce (the size of) symbols and/or fonts to save memory (that options already exist), but what I'm proposing goes in the opposite direction, i.e. improving readability for older eyes, perhaps using a bigger font for the symbols and/or title bar, and/or by inverting the colors of the 1,2,3 numbers actually being used for that (like some clones do).

We all know this would use more lines of code, but only the developers or somebody who already did it can assess how many Bytes it would be. If I understand this correctly, the bitmaps of 1,2,3 are going to consume a few Bytes itself (for instance 24B+ on 8px_tall numbers and 96B+ on 16px_tall numbers). What it's going to use more Bytes would it be the routine for selecting one font/character or the other.

Another alternative I'm working on is to create bold fonts 10x16 and 12x16. That wouldn't have impact code-wise.

Anyways, whatever we conclude for this low-priority enhancement, it's going to be optional, so each one can make the best-suiting combo of features  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 04, 2021, 04:27:58 pm
For those with an HD44780 based display (2x16) and missing characters at the beginning of the first line (m-firmware):
- caused by a slow LCD controller which needs more time for clearing the display
- edit function LCD_Clear() in HD44780.c and increase the delay to 3-5 ms until the output is fine
Code: [Select]
LCD_Cmd(CMD_CLEAR_DISPLAY);      /* send clear command */
MilliSleep(2);                   /* LCD needs some time for processing */
Title: Re: $20 LCR ESR Transistor checker project
Post by: jshonw on November 06, 2021, 11:15:09 pm
What's the minimum wattage that can be used for the 470k and 680 ohm resistors?  I want to use smd precision resistors and 1/8 watt seems to be the most economical.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on November 06, 2021, 11:26:42 pm
The AVR uses 5V, so any resistor of 1/16W or more should work fine (for the I/O).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 13, 2021, 12:27:04 pm
If you like to beta-test the ringtester (requires ringtester frontend) or logic probe (requires dedicated ADC pin with 4:1 voltage divider and rotary encoder) please drop me an email.

Edit: Latest additions are continuity check with buzzer and third profile for adjustment values.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lordium on November 18, 2021, 07:09:42 am
Had some issues with my TC1 not shutting down properly. Last time this happened I reflashed the U4 IC and that worked. But this time that would not work so I replaced it with the transistor version (can be found here in this thread). Just though I'd show some pictures of it to inspire others with same problem. Basically pads on bottom that solder to the pcb and then through vias to top.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TheBay on November 18, 2021, 10:47:14 am
Had some issues with my TC1 not shutting down properly. Last time this happened I reflashed the U4 IC and that worked. But this time that would not work so I replaced it with the transistor version (can be found here in this thread). Just though I'd show some pictures of it to inspire others with same problem. Basically pads on bottom that solder to the pcb and then through vias to top.

What issue did you have with the TC1 not shutting down? I have one "original" TC1 that the battery will go flat on its own when left for a few days, but I have a clone of a clone TC1 that works perfectly and the battery is never discharged.
I quite fancy modifying the problematic TC1 I have.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on November 18, 2021, 02:50:56 pm
My ~4 yr old TC-7 (blue panel, yellow button, wider screen) had the same issue with eating the battery. My solution was to just install a DPDT 8mm x 8mm push latch switch inside and exposed it on the bottom edge near the micro USB charge port. Just do a physical on before starting use then use the normal button until you're done then hard shut if off.

Attached is a pic of all 7 of my testers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 19, 2021, 12:01:47 am
...Comments are welcome ...

Hello Yuriy,

... your Color-Testversion looks very nice, bat at my TTester GM328A I have to change some items in the Makefile befor I can test it.

For that I need the changed source-files from you so I can compile it again.

Many thanks and best regards

Horst

Do you have english version? i like this firmware and need to try
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on November 19, 2021, 12:08:17 am
Below you will see a summary of the main issue with the TC1 (and similars), and it's workarounds:
Whoever manufactures the TC-1 has made some changes (control MCU U4) which are incompatible with k and m-firmware. For running one of the OSHW firmwares the changes need to be undone. One way is to reprogram U4 (https://github.com/atar-axis/tc1-u4), and the other way is to replace U4 by a small circuit (https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/TC1-Mod.kicad.tgz). The TC-1 also has a few issues with poorly chosen components, especially around the voltage booster for the Zener test. I'd recommend to replace MLCCs C11 and C1 with a 10 or 22µF low-ESR electrolytic rated for 100V.
For more details you can search the related posts on this thread starting around june 2018.
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 19, 2021, 01:19:13 am
Firmware for GM328A with display of different Gamma. Last modified Ttester Karl-Heinz Kübbeler 1.13k + color
Changed some colors in the BGR version

Hi Yuriy_K
I have tried this firmware ST7735_RGB_en.zip https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1221711 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1221711) and I don't see the VOLTAGE menu, can you add

thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on November 19, 2021, 03:38:07 am

and I don't see the VOLTAGE menu, can you add

thank
After optimizing the source code, it became possible to add this to the menu.
Changed archive
Who repeats the situation described below?
Everything works fine for me.
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 19, 2021, 09:50:59 am

and I don't see the VOLTAGE menu, can you add

thank
After optimizing the source code, it became possible to add this to the menu.
Changed archive

Hi Yuriy_K
This firmware works, but I don't understand why I have to press push 2 to 3 times to start, if only pressing the button 1 times clone doesn't turn on.


thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: lordium on November 19, 2021, 10:13:50 am

What issue did you have with the TC1 not shutting down? I have one "original" TC1 that the battery will go flat on its own when left for a few days, but I have a clone of a clone TC1 that works perfectly and the battery is never discharged.
I quite fancy modifying the problematic TC1 I have.

Wasn't shutting down properly. Stuck with screen on saying something along the lines of "shutting down, bye bye". Measured 3.7uA current with it turned off as it is now. Attached kicad project for reference. Guess you can tweak some components or values if you need better result or have different parts in hand compared to what I had (some space available for larger components). This was just a quick and easy fix so didn't spend real any time on it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 19, 2021, 03:20:37 pm

and I don't see the VOLTAGE menu, can you add

thank
After optimizing the source code, it became possible to add this to the menu.
Changed archive

Hi Yuriy_K
This firmware works, but I don't understand why I have to press push 2 to 3 times to start, if only pressing the button 1 times clone doesn't turn on.


thank
I have tried this firmware https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/Markus%20Reschke/English/16MHz (https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/Markus%20Reschke/English/16MHz) and the same problem when I press the button once the screen just flashes, if I long time press the button, or press it many times quickly, the clone can start life. I use clone AY-AT / GM328A

then I tried the firmware https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/Karl-Heinz%20K%C3%BCbbeler%20 (https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/Karl-Heinz%20K%C3%BCbbeler%20) and the problem is gone, the clone can be turned on with just 1 button press. I'm sure it's not a hardware malfunction, please anyone who knows any advice is appreciated


Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on November 19, 2021, 04:05:19 pm
then I tried the firmware https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/Karl-Heinz%20K%C3%BCbbeler%20 (https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/Karl-Heinz%20K%C3%BCbbeler%20) and the problem is gone, the clone can be turned on with just 1 button press. I'm sure it's not a hardware malfunction, please anyone who knows any advice is appreciated
Over the course of three years, Karl-Heinz made a lot of changes to the source code. My color additions added even more changes. Recently I made a color version of mega644_T7_Mod on this library. Everything worked without errors.
Check the parts pointed to by the arrows, especially the resistors ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 20, 2021, 01:39:29 am
Over the course of three years, Karl-Heinz made a lot of changes to the source code. My color additions added even more changes. Recently I made a color version of mega644_T7_Mod on this library. Everything worked without errors.
Check the parts pointed to by the arrows, especially the resistors ...
Hi Yuriy_K
I really appreciate your hard work in building the color firmware.

I have checked the transistors S9012, R3K3 and R33K as well as S9014 which is connected to the switch, I see everything is fine. measurements were also taken, I even tried to replace the components with the same value. there is something strange when try to attach the 6PIN cable for the programmer to the IDE USB ISP, it should be 5V connected via USB ISP can be start and testing the clone (without battery connect to LCR, only USB to ISP 6PIN) it should start to testing. but what I see with the above firmware is just a "white screen" on the Clone LCD display.

so which other parts to check? I will check everything..

Direct 5V VCC source (no LDO, no SWITCH) can't turn on the LCR with Yuriy_K's new color firmware in post #7273
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1326938 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1326938)
and the M firmware in
https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/Markus%20Reschke/English/16MHz (https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/Markus%20Reschke/English/16MHz)
only "white screen" on LCD.

while with the Yuriy_K firmware on post #6912
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1221711 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1221711)
and the K firmware in
https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/Karl-Heinz%20K%C3%BCbbeler%20/English/16Mhz (https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/Karl-Heinz%20K%C3%BCbbeler%20/English/16Mhz) my GM328A clone it worked fine.

it looks like the firmware doesn't respond immediately to turn on the atmega when the ON button is pressed, whether my clone is bad?? or if someone has a GM328A please test the above firmware and provide a report, if it works well on your clone, then obviously the problem is in the my hardware GM328A bad.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on November 20, 2021, 06:23:25 am
it looks like the firmware doesn't respond immediately to turn on the atmega when the ON button is pressed, whether my clone is bad?? or if someone has a GM328A please test the above firmware and provide a report, if it works well on your clone, then obviously the problem is in the my hardware GM328A bad.
I do not know in what version the board of your GM328A, if, as in message 6916, then temporarily unsolder C8 10uF. Check how the tester turns on, if normal, then the reason is 7550 or S9012. About the selection of S9012 in detail at the beginning of page 278. I replaced 7550 with 7350, it works fine or look on the forum pages ...
When 5V is applied to Vcc, the "white screen" turns on, after 0.5 seconds the command to clear the screen passes and the messages are displayed as in the photo. There is no reaction to the button, since the low voltage protection is triggered. After 5 seconds, the tester turns off.

I have no testers with your display, this tester is built on ILI9341.
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 20, 2021, 07:16:33 am
I do not know in what version the board of your GM328A, if, as in message 6916, then temporarily unsolder C8 10uF. Check how the tester turns on, if normal, then the reason is 7550 or S9012. About the selection of S9012 in detail at the beginning of page 278. I replaced 7550 with 7350, it works fine or look on the forum pages ...
When 5V is applied to Vcc, the "white screen" turns on, after 0.5 seconds the command to clear the screen passes and the messages are displayed as in the photo. There is no reaction to the button, since the low voltage protection is triggered. After 5 seconds, the tester turns off.

I have no testers with your display, this tester is built on ILI9341.

I have removed C8 the value of 10uF, and then tried again the result is still the same, I use smd 9012 with code 2T1 and use LDO HT7550, I don't think this is a problem Battery wire up to LDO 5V, because it's true what you said should be VCC with external 5V (without LDO ) then the clone tester should flash and turn on even though the 4V and EMPTY! battery logo appears but on firmware M and your latest color firmware, it doesn't show anything, only "white screen" waits more than 5 seconds even more than 1 minute the screen stays "white screen" different from firmware K uploaded on yandex disk for GM328A and your color firmware on page 277 all works fine (no bug here). so my clone is normal with firmware K and your color firmware is on page 277, but my clone GM328A has an error (white screen) with firmware M and your new color firmware is page 291. it should be without battery, clone I should display a 4V EMPTY! screen the same as the clone you are using.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 20, 2021, 07:46:56 am
frank19,Show good quality pictures of your clone from 2 sides. You should always do this when asking questions about the circuitry.
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 20, 2021, 08:03:31 am
frank19,Show good quality pictures of your clone from 2 sides. You should always do this when asking questions about the circuitry.

GM328A
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 20, 2021, 08:15:39 am
Take 1 more photo with the display removed
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 20, 2021, 08:30:15 am
Take 1 more photo with the display removed

like your post on #6916
crystal changed to 16MHz
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 20, 2021, 08:54:38 am
Try firmware 1.41Mod from this archive https://disk.yandex.ru/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke/English/16MHz. Before you fill in the firmware do a complete cleaning of the whole chip and set fuses H-D9 L-F7 Ext-FD(05) correctly!
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 20, 2021, 09:24:56 am
Try firmware 1.41Mod from this archive https://disk.yandex.ru/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke/English/16MHz. Before you fill in the firmware do a complete cleaning of the whole chip and set fuses H-D9 L-F7 Ext-FD(05) correctly!

Hi indman
thanks this is very useful information, i have wiped clean all firmware then reset fuse, and now my clone is working with new firmware Yuriy_K

I understand the situation, I will try to recreate the old library and make you firmware, but this may take several days. Karl-Heinz made a lot of changes and I adjusted my sources to his changes without keeping my old sources. Wait.

Hi Yuriy_K
thanks, your firmware is working fine now. I don't understand if I have to delete everything and set the fuse for your new firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on November 20, 2021, 10:00:35 am

thanks, your firmware is working fine now. I don't understand if I have to delete everything and set the fuse for your new firmware.
If the new firmware has worked, then leave it, the latest changes by Karl-Heinz are implemented in it. This state is prepared for new changes in firmware version "k". And I don't need to roll back to the previous state. All the best to you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 25, 2021, 11:49:06 am
I've ordered a pair of MAX6675 and MAX31855 modules/PCBs (thermocouple converters), but they will arrive end of January. If someone likes to sponsor modules/PCBs with a faster delivery time please let me know.

Edit: I've added support for MAX6675 and MAX31855 to the firmware but can't test them as I don't have the modules yet. If you have a MAX6675 or MAX31855 module/PCB and like to beta-test please drop me an email. MAX31855 has a Vcc of 3.3V a needs level shifters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 27, 2021, 10:11:54 am
I've ordered a pair of MAX6675 and MAX31855 modules/PCBs (thermocouple converters), but they will arrive end of January. If someone likes to sponsor modules/PCBs with a faster delivery time please let me know.

Edit: I've added support for MAX6675 and MAX31855 to the firmware but can't test them as I don't have the modules yet. If you have a MAX6675 or MAX31855 module/PCB and like to beta-test please drop me an email. MAX31855 has a Vcc of 3.3V a needs level shifters.

Hi madires
does it mean that the transistor tester can measure temperature by adding a MAX6675 module?
Title: Re: $20 LCR ESR Transistor checker project
Post by: SeamlessPurse on November 27, 2021, 11:03:26 am
Which tester is preferred? There is many types on Ali. Eh, T4, 328a, 328b, 328p
 Some with signal generator etc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 27, 2021, 11:45:06 am
does it mean that the transistor tester can measure temperature by adding a MAX6675 module?

Yep, the next m-firmware version will support that. You need an SPI bus with MISO and an unused pin for the MAX6675's /CS. This is meant for ATmega324/644/1284 based testers (the 328 doesn't have enough pins).

Edit: Other temperature sensors already supported are DS18B20 and the DHTxx family which are connected via the standard probes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 27, 2021, 11:53:09 am
Which tester is preferred? There is many types on Ali. Eh, T4, 328a, 328b, 328p
 Some with signal generator etc.

Please see https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf for a list of common tester clones. Basically all testers with an ATmega328 or better support the PWM and square wave generator features (needs to be activated in the firmware). 
Title: Re: $20 LCR ESR Transistor checker project
Post by: rsjsouza on November 27, 2021, 10:55:16 pm
Great list of clones! I got the GM328A (will arrive in a few weeks) and the store (https://pt.aliexpress.com/item/33004956110.html?spm=a2g0s.9042311.0.0.4069b90a3bJhFw) says it supports IR encoder, but the spreadsheet simply says "encoder". I suspect these are the same thing, right? 

Alas, if I had seen this I would probably have opted for the LCR-T7 with higher Zener voltages.

Title: Re: $20 LCR ESR Transistor checker project
Post by: ricktendo on November 27, 2021, 11:10:44 pm
I am getting a GM328A in a few weeks, can anybody tell me what "k" firmware is compatible with this board (is 'mega328_GM328' correct, I see some using "color" firmware)

Also is there a list of hardware mods, I saw a video where a 10K resistor connection was repaired and there is this post (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3575378/#msg3575378) talking about downgrading a resistor under the LCD
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 28, 2021, 08:08:31 am
Great list of clones! I got the GM328A (will arrive in a few weeks) and the store (https://pt.aliexpress.com/item/33004956110.html?spm=a2g0s.9042311.0.0.4069b90a3bJhFw) says it supports IR encoder, but the spreadsheet simply says "encoder". I suspect these are the same thing, right? 
The Encoder in the table means that this clone has this operating mode HW control(rotary encoder).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 28, 2021, 12:18:16 pm
I am getting a GM328A in a few weeks, can anybody tell me what "k" firmware is compatible with this board (is 'mega328_GM328' correct, I see some using "color" firmware)

That would be mega328_color_kit  (AY-AT/GM328A clones).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 28, 2021, 12:55:53 pm
Great list of clones! I got the GM328A (will arrive in a few weeks) and the store (https://pt.aliexpress.com/item/33004956110.html?spm=a2g0s.9042311.0.0.4069b90a3bJhFw) says it supports IR encoder

Some remarks about clones and IR RC. The clones' modified firmware supports just one or two IR protocols (mostly NEC). This is the first time I've seen that they also added a sender. The IR receiver module is usually connected via the probes. Only TC-1 and family come with a fixed IR receiver. The m-firmware can do both, i.e. probes or dedicated pin. And it supports up to 20 IR protocols in Rx mode and up to 15 in Tx mode. For sending IR you can connect an IR LED directly (low range) or use a simple circuit with a transistor to drive the IR LED with more current.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on November 28, 2021, 09:39:23 pm
Very silly question, is there any video of how to install this firmware?

Pregunta muy tonta, hay algun video de como instalan este firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rsjsouza on November 28, 2021, 09:49:36 pm
Great list of clones! I got the GM328A (will arrive in a few weeks) and the store (https://pt.aliexpress.com/item/33004956110.html?spm=a2g0s.9042311.0.0.4069b90a3bJhFw) says it supports IR encoder

Some remarks about clones and IR RC. The clones' modified firmware supports just one or two IR protocols (mostly NEC). This is the first time I've seen that they also added a sender. The IR receiver module is usually connected via the probes. Only TC-1 and family come with a fixed IR receiver. The m-firmware can do both, i.e. probes or dedicated pin. And it supports up to 20 IR protocols in Rx mode and up to 15 in Tx mode. For sending IR you can connect an IR LED directly (low range) or use a simple circuit with a transistor to drive the IR LED with more current.
madires, thank you for the clarification. I will put the encoder funcionality to run and report back my results when the unit arrives.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ricktendo on November 28, 2021, 10:22:53 pm
Any tutorial/instructions on how to compile the "m" firmware?

I already know how to do the "k" and would like to test both.

Edit:
Very silly question, is there any video of how to install this firmware?

Pregunta muy tonta, hay algun video de como instalan este firmware?
That depends on what transistor tester you have. But it will require either an AVR programmer board (Arduino, Teensy, UsbAsp, etc)

Depende de cual transistor tester tienes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on November 29, 2021, 01:38:34 am
Any tutorial/instructions on how to compile the "m" firmware?

I already know how to do the "k" and would like to test both.

Edit:
Very silly question, is there any video of how to install this firmware?

Pregunta muy tonta, hay algun video de como instalan este firmware?
That depends on what transistor tester you have. But it will require either an AVR programmer board (Arduino, Teensy, UsbAsp, etc)

Depende de cual transistor tester tienes.

I own this GM328A, I also have arduino uno and mega boards
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2021, 11:22:09 am
Any tutorial/instructions on how to compile the "m" firmware?

I already know how to do the "k" and would like to test both.

Please see:
- README and Clones in the firmware archive
- https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/ctester-1.44m.pdf
- https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/FAQ.Feliciano.pdf
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2021, 11:37:15 am
I own this GM328A, I also have arduino uno and mega boards

k-firmware: see mega328_color_kit directory
m-firmware: see Clones files for settings for AY-AT/GM328A and compile firmware
Arduino: flash ArduinoISP from the example sketches and use the Arduino as ISP programmer
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on November 29, 2021, 04:13:14 pm
Very silly question, is there any video of how to install this firmware?
Basically, the steps are the following:
Here a simplified Spanish video of the overall procedure:
https://www.youtube.com/watch?v=2sypoyHJck0 (https://www.youtube.com/watch?v=2sypoyHJck0)
(For those who don't speak Spanish, perhaps the images sequence can be somehow helpulf anyways).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on November 29, 2021, 05:29:01 pm
Gracias felicano, despues me di cuenta que era igual que como le cargue el bootleader de arduino  a los atmega328P virgenes que traje de china. saludos cordiales hermano.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on November 29, 2021, 07:35:40 pm
Gracias felicano, despues me di cuenta que era igual que como le cargue el bootleader de arduino  a los atmega328P virgenes que traje de china. saludos cordiales hermano.
You're welcome (an please remember this is an English forum).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on November 29, 2021, 10:46:42 pm
I do the calibration, but it reads anything the capacitors, the rest of it well, what am I failing in?

In the video that Feliciano posted at minute 8.10, he puts a 100nF capacitor, I see all of what I have as 44 to 49 nf, and those with less than 4-30 nf also measure with error, the other components measure it well after calibrating

I use the same version as in the video, I downloaded it from there



realizo la calibracion, pero lee cualquier cosa los capacitores, lo demas bien, en que estoy fallando??

en el video que posteo Feliciano en el minuto 8,10 pone un capacitor de 100nF, a mi a todos lo que tengo me los ve como de 44 a 49 nf, y al de menos de 4-30 nf tambien mide con error, los demas componentes lo mide bien despues de calibrar

uso la misma version que en el video, la descargue desde ahi mismo
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on November 30, 2021, 12:56:18 am
Try firmware 1.41Mod from this archive https://disk.yandex.ru/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke/English/16MHz. Before you fill in the firmware do a complete cleaning of the whole chip and set fuses H-D9 L-F7 Ext-FD(05) correctly!

Hi indman
thanks this is very useful information, i have wiped clean all firmware then reset fuse, and now my clone is working with new firmware Yuriy_K

I understand the situation, I will try to recreate the old library and make you firmware, but this may take several days. Karl-Heinz made a lot of changes and I adjusted my sources to his changes without keeping my old sources. Wait.

Hi Yuriy_K
thanks, your firmware is working fine now. I don't understand if I have to delete everything and set the fuse for your new firmware.

To use this firmware 1.41 should I change the 8MHz crystal for a 16MHZ? and something else or just that?

Para usar este firmware 1.41 debo cambiar el cristal de 8MHz por una de 16MHZ?? y algo mas o solo eso?

Title: Re: $20 LCR ESR Transistor checker project
Post by: tsmith35 on November 30, 2021, 02:36:21 am
I am amazed at the amount of time, effort and money spent on these little transistor testers. If not for a handful of creative minds (thank you!) coming together to develop this amazingly popular device, very many people would have missed out on the unique opportunity to dive into electronics, programming and development. Many thanks to you guys.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on November 30, 2021, 04:35:48 am
To use this firmware 1.41 should I change the 8MHz crystal for a 16MHZ? and something else or just that?
Frank19 installed a 16MHz crystal and new firmware was indicated or created for it.
Capacitors greater than 100 nF must be used to calibrate capacitors. A 5-30 nF capacitor is used to set up the resonant method for measuring small inductances, see my post 7115 on page 285.
For "k" firmware, a 16MHz crystal allows measuring inductances starting from 60 nH versus 200 nH for an 8 MHz crystal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pierreraymondrondelle on November 30, 2021, 10:55:55 am
Very silly question, is there any video of how to install this firmware?

Pregunta muy tonta, hay algun video de como instalan este firmware?

Hi, This may help you:
https://www.eevblog.com/forum/beginners/usbasp-programming-atmel-328p/ (https://www.eevblog.com/forum/beginners/usbasp-programming-atmel-328p/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on November 30, 2021, 11:13:12 am
Ttesters with installed software Karl-Heinz Kübbeler 1.13k, after minor alterations, can test IGBT transistors. Everything in the picture ...

Checked out similar add-ons for ComponentTester-1.43m. With insufficient gate voltage, an additional battery allows you to get readings ...

Why IGBT 40N60 not support, only detect diode and capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on November 30, 2021, 11:57:06 am
Do you have several of those? According to the datasheets I've read, some can have Vge_threshold above 5V (and others below that, depending on the manufacturer and batch).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on November 30, 2021, 01:04:45 pm
https://www.youtube.com/watch?v=UFMsNgW0bqs (https://www.youtube.com/watch?v=UFMsNgW0bqs)

Excuse me that the video is not well aligned, here I show after trying several times with different capacitors that do not calibrate, I have tried with different atmega328, with 9 v and 12v, the version with which I flash is the video that they published here  [url=https://www.youtube.com/watch?v=2sypoyHJck0&t=324s]https://www.youtube.com/watch?v=2sypoyHJck0&t=324s] [url]https://www.youtube.com/watch?v=2sypoyHJck0&t=324s]https://www.youtube.com/watch?v=2sypoyHJck0&t=324s]https://www.youtube.com/watch?v=2sypoyHJck0&t=324s] [url]https://www.youtube.com/watch?v=2sypoyHJck0&t=324s (http://[url=https://www.youtube.com/watch?v=2sypoyHJck0&t=324s)[/url]


Disculpen que el video no este bien alineado, aca muestro despues de probar varias veces con distintos capacitores que no calibra, he probado con distintos atmega328, con 9 v y 12v, la vesion con la que flasheo es la del video que publicaron aca https://www.youtube.com/watch?v=2sypoyHJck0&t=324s (https://www.youtube.com/watch?v=2sypoyHJck0&t=324s)


PD: Para usar este firmware 1.41 debo cambiar el cristal de 8MHz por una de 16MHZ ?? y algo mas o solo eso?
https://disk.yandex.ru/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke/English/16MHz (https://disk.yandex.ru/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke/English/16MHz)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 30, 2021, 02:18:53 pm
PD: Para usar este firmware 1.41 debo cambiar el cristal de 8MHz por una de 16MHZ ?? y algo mas o solo eso?
This is an English forum, write in English so others can understand you!
Here is the m-firmware 1.41Mod for different quartz frequencies https://disk.yandex.ru/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke/English Do not use the calibration capacitors you showed in your video. They are of poor quality. Read in the manual for the k-firmware what type and quality of capacitors are needed for correct calibration.

PS Before you fill in the firmware do a complete cleaning of the whole chip and set fuses H-D9 L-F7 Ext-FD(05) correctly!
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on November 30, 2021, 02:44:19 pm
I am the author of that video, and the firmware, both M and K, is prepared for 20Mhz crystal.
Check if that may be the problem.
In that video I update the firm K, but I also do it without the M without major problem.
The firmware that I posted is that I am using at the moment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on November 30, 2021, 02:53:05 pm
I am the author of that video, and the firmware, both M and K, is prepared for 20Mhz crystal.
Check if that may be the problem.
In that video I update the firm K, but I also do it without the M without major problem.
The firmware that I posted is that I am using at the moment.

Friend, I do not mean that your firmware is wrong, I refer to your video so they know where you download it from. thanks for your contribution
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on November 30, 2021, 04:56:42 pm
Ttesters with installed software Karl-Heinz Kübbeler 1.13k, after minor alterations, can test IGBT transistors. Everything in the picture ...

Checked out similar add-ons for ComponentTester-1.43m. With insufficient gate voltage, an additional battery allows you to get readings ...

Why IGBT 40N60 not support, only detect diode and capacitor.
Here, on a larger scale, additional input terminals are used to measure those IGBTs that need more gate voltage. I cannot load my color "m" firmware into the ATmega328, there is not enough memory.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on November 30, 2021, 05:26:44 pm
I am the author of that video, and the firmware, both M and K, is prepared for 20Mhz crystal.
Check if that may be the problem.
In that video I update the firm K, but I also do it without the M without major problem.
The firmware that I posted is that I am using at the moment.

si ese es el problema con el de 16mhz se acerca, por las dudas no tenes el que esta preparado para 16mhz??
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on December 01, 2021, 12:53:44 pm
I was seeing that there is a GM328A, which has the option IR decoder-IRencoder and DTH11, someone has it firmware, see minute 11:04 onwards, https://www.youtube.com/watch?v=I-jHFmPkTsk (https://www.youtube.com/watch?v=I-jHFmPkTsk)

Estaba viendo que hay un GM328A, que tiene la opcion IR decoder-IRencoder y DTH11, alguien tiene es firmware, ver minuto 11:04 en adelante
Title: Re: $20 LCR ESR Transistor checker project
Post by: rsjsouza on December 01, 2021, 06:56:54 pm
I was seeing that there is a GM328A, which has the option IR decoder-IRencoder and DTH11, someone has it firmware, see minute 11:04 onwards,
This is probably the one that I got (and is still in transit to here).

Additional explanation is provided by madires in the previous post:

Great list of clones! I got the GM328A (will arrive in a few weeks) and the store (https://pt.aliexpress.com/item/33004956110.html?spm=a2g0s.9042311.0.0.4069b90a3bJhFw) says it supports IR encoder

Some remarks about clones and IR RC. The clones' modified firmware supports just one or two IR protocols (mostly NEC). This is the first time I've seen that they also added a sender. The IR receiver module is usually connected via the probes. Only TC-1 and family come with a fixed IR receiver. The m-firmware can do both, i.e. probes or dedicated pin. And it supports up to 20 IR protocols in Rx mode and up to 15 in Tx mode. For sending IR you can connect an IR LED directly (low range) or use a simple circuit with a transistor to drive the IR LED with more current.
madires, thank you for the clarification. I will put the encoder funcionality to run and report back my results when the unit arrives.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 01, 2021, 07:52:19 pm
I was seeing that there is a GM328A, which has the option IR decoder-IRencoder and DTH11, someone has it firmware, see minute 11:04 onwards
Guys, this Chinese firmware for GM328A(AY-AT) tester has long been lying on my resource here https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A/Firmware/OriginalEn(8MHz)
Only for 8Mhz crystal and based on k-firmware outdated version 1.12k
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on December 02, 2021, 02:39:14 am

Here, on a larger scale, additional input terminals are used to measure those IGBTs that need more gate voltage. I cannot load my color "m" firmware into the ATmega328, there is not enough memory.

if using k firmware with add 3.1V battery like your picture is it possible?
Title: Re: $20 LCR ESR Transistor checker project
Post by: frank19 on December 02, 2021, 02:47:25 am
This is an English forum, write in English so others can understand you!
Here is the m-firmware 1.41Mod for different quartz frequencies https://disk.yandex.ru/d/yW8xa5NJgUo5z/M328Kit%2BTFT/Firmware/Markus%20Reschke/English Do not use the calibration capacitors you showed in your video. They are of poor quality. Read in the manual for the k-firmware what type and quality of capacitors are needed for correct calibration.

PS Before you fill in the firmware do a complete cleaning of the whole chip and set fuses H-D9 L-F7 Ext-FD(05) correctly!

what do you think about using WIMA Film Capacitor?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on December 02, 2021, 05:00:10 am
if using k firmware with add 3.1V battery like your picture is it possible?
The addition of the circuit shown in the previous message is suitable for "m" firmware and "k" firmware starting from 1.13k.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 02, 2021, 07:18:49 am
what do you think about using WIMA Film Capacitor?
This type of capacitor is good for calibration! Only it is desirable to choose a capacity rating greater than 100nF
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on December 02, 2021, 09:51:25 am
the firmware in english for the 16MHz GM328A by Markus Reschke, did someone find it to download already compiled? because I only found it in Russian for 8MHz

in spanish
el firmware en ingles para el GM328A   de 16MHz de Markus Reschke alguien lo encontro para descargarlo ya compilado?? porque yo solo lo encontre en ruso para 8MHz
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 02, 2021, 10:00:54 am
Adrian_Arg.,I don't understand why you are going through every possible firmware for the tester?
What do you want to get out of your tester? If your clone has a hardware defect, no firmware can fix it!
Above is the link https://disk.yandex.ru/d/yW8xa5NJgUo5z to my firmware archive with m-firmware in English for GM328A - there's also a folder is called M328Kit+TFT(AY-AT). Look carefully and you'll find everything.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on December 02, 2021, 10:49:18 am
Adrian_Arg.,I don't understand why you are going through every possible firmware for the tester?
What do you want to get out of your tester? If your clone has a hardware defect, no firmware can fix it!
Above is the link https://disk.yandex.ru/d/yW8xa5NJgUo5z to my firmware archive with m-firmware in English for GM328A - there's also a folder is called M328Kit+TFT(AY-AT). Look carefully and you'll find everything.

install version 1.41 for gm328A and the problem I have is that I have to press three times to turn it on and and when I go to calibrate it asks me to short the three tips, and there it stays it does not advance. for that reason ask for 1.44. the one from colleague feliciano is for a 20mhz gm328a and I didn't get a 20mhz crystal, only the 16mhz one. Cheers


in spanish
instale la version 1.41 para gm328A y el problema que tengo es que tengo que presionar tres veces para que encienda y y cuando voy a calibrar me pide que ponga en corto las tres puntas, y ahi se queda no avanza. por ese motivo pregunte por la 1.44. la del colega feliciano es para gm328a de 20mhz y no consegui cristal de 20mhz, solo el de 16mhz. saludos
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 02, 2021, 11:24:43 am
Once again -If your clone has a hardware defect, no firmware can fix it!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on December 02, 2021, 12:01:06 pm
Once again -If your clone has a hardware defect, no firmware can fix it!

No, the module has no problems, since I read on this site that the same thing happens to some, they have to press the ignition several times, and with other firmware it works well, what happens is that I am looking for the most polished, ok

in spanish

no el modulo no tiene problemas, ya que lei en este sitio que a algunos le pasa lo mismo deben presionar varias veces el encendido, y con otros firmware funciona bien, lo que pasa es que busco el mas pulido, ok
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 02, 2021, 12:24:51 pm
No, the module has no problems, since I read on this site that the same thing happens to some, they have to press the ignition several times, and with other firmware it works well, what happens is that I am looking for the most polished, ok
Firmware, which are lying on my resource, checked a lot of people on a number of similar clones like yours and do not cause any such problems, as you think and write.
If the tester does not turn on after pressing the Test button on any firmware, it means that the device has problems. Which ones - this needs to be carefully analyzed and understood.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 02, 2021, 01:14:22 pm
Once again -If your clone has a hardware defect, no firmware can fix it!
No, the module has no problems, since I read on this site that the same thing happens to some, they have to press the ignition several times, and with other firmware it works well, what happens is that I am looking for the most polished, ok
Have you read the 294 pages of this thread, and/or made a thourough search through it? Several users have reported failures of that kind with their clones. In most cases is due:
a)failure to flash the firmware (force erase the AVR and then flash the firmware AND correctly set the fuses)
b)failure with the power supplies/regulators of their clones, or failures of the layout (I recall somebody found a short on one of the PCB traces, and somebody else found a bad placed regultator, I had a shorted ceramic capacitor on one unit, and bad solder on other unit, etc.)
c)failure of the microcontroller
BTW: don't forget disconnect the programming cable and anything external attached to the unit before attempting to use it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on December 02, 2021, 02:17:17 pm
If I'm going to test what you say, your firmware is fine but it is for 20MHz and I only got 16MHz in my city, so I had to remove it.

in spanish
Si voy a probar lo que tu dices, tu firmware esta bien pero es para 20MHz y solo consegui de 16MHz en mi ciudad, asi que lo tuve que sacar.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on December 02, 2021, 02:45:47 pm
@Adrian_Arg.

First of all a warning: THIS TOPIC IS IN ENGLISH !!!

I'm not a good English speaker either, but I use google translate to translate text from Romanian to English; you can do the same! Let's respect each other!

Secondly, if you want a certain firmware version, with certain options, why not make one yourself? It's not hard at all.

To compile which version you want, use the programs in indman's archive - many thanks! - from the "help" folder here: https://disk.yandex.ru/d/yW8xa5NJgUo5z/Help/Editing%20and%20compilation%20of%20a%20firmware. 

Good luck with that!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Muttley Snickers on December 03, 2021, 05:00:11 am
My GM328A arrived this morning and it seems to work okay but I was surprised at just how dusty it was.   :o

Another thing, the Ebay store (https://www.ebay.com.au/itm/393455706111) that I purchased it from indicated that it would be a DIP package but it’s not. I would have preferred a DIP because I already have a couple of spares in case something silly happens or for any future enhancements.   :-/O

Edit: Improved Images.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 07, 2021, 04:20:17 pm
Edit: I've added support for MAX6675 and MAX31855 to the firmware but can't test them as I don't have the modules yet. If you have a MAX6675 or MAX31855 module/PCB and like to beta-test please drop me an email. MAX31855 has a Vcc of 3.3V a needs level shifters.

Surprisingly the thermocouple converters I've ordered turned up early and both work fine. BTW, if you have a MAX31855 make sure it has a 10nF MLCC across the thermocouple input to reduce noise.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 07, 2021, 08:31:10 pm
As promised a few pages back, here are some inverted_color_numbers [1,2,3] bitmaps to be integrated on next releases as an optional way for enhanced readability of the components_pins displayed (on ctesters with enough memory).

EDIT: Currently developed: 6x8, 8x8, 10x16, and 12x16 (all hf).

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 17, 2021, 12:17:12 pm
I have an early Xmas gift for you:

v1.45m
- New hardware options: MAX6675 and MAX31855 thermocouple converters (HW_MAX6675, HW_MAX31855, suggested by ricktendo@EEVblog).
- Added option to have three profiles for adjustment values (UI_THREE_PROFILES, suggested by indman@EEVblog).
- Added continuity check (SW_CONTINUITY_CHECK, suggested by indman@EEVblog).
- New hardware option: audible indicator, i.e. active buzzer (HW_BUZZER, suggested by indman@EEVblog).
- New hardware option: logic probe (HW_LOGIC_PROBE, suggested by Dumidan@EEVblog).
- Fixed A-C diode symbol, A umlaut and U umlaut in font_12x16_hf.h and font_12x16_iso8859-2_hf.h (reported by Feliciano@EEVblog).
- New hardware option: ring tester (LOPT/FBT tester, HW_RING_TESTER).
- Added option to choose between staying in the main menu or automatically exiting (UI_MAINMENU_AUTOEXIT).
- Updated font_8x8_hf.h (thanks to Feliciano@EEVblog).

Please download at:
- https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
- https://github.com/kubi48/TransistorTester-source/tree/master/Markus (some time later)

For the ringtester frontend:
- https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/RingTester-Option.pdf
- other frontends should also work fine
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 17, 2021, 03:16:24 pm
Thanks madires! :-+ This is a great another gift for the holidays!
Now all that's left is to teach this device how to make coffee in the morning. ;D
He can do everything else already.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rsjsouza on December 17, 2021, 06:17:39 pm
My GM328A arrived yesterday. It is quite different than the one shown in the listing, but I got more than I bargained for: it came with a nifty box and it seems reasonably well made. Feature-wise, it is the same as the GM328A shown in the listing.

Amazing piece of kit. Really versatile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jacon on December 17, 2021, 09:51:57 pm
Hi Marcus,

Enclosed pls find fixed polish_2 translation  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on December 18, 2021, 05:10:57 pm
Hello Marcus,

Here is the updated file for the Romanian language.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on December 19, 2021, 07:04:13 am
Hi Marcus.

Here is the updated file for the Spanish language.

A greeting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 19, 2021, 06:16:48 pm
Madires I updated Russian translation of var_russian.h file and also pdf version of Russian manual for version 1.45m. In the pdf examples of connection of hardware options ring tester, buzzer, LC-meter are added  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: lotec25 on December 20, 2021, 12:49:32 am
Can someone point me to what post has the needed hardware that needs to be upgraded? Like the encoder, crystal etc? I have the "Multi-function Tester, Longruner 1.8 inch Colorful Display Pocketable Multifunctional TFT Backlight Transistor LCR-TC1 Tester"
https://www.amazon.com/gp/product/B07C5LC486/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 (https://www.amazon.com/gp/product/B07C5LC486/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) 

Thanks
Rob
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 20, 2021, 11:28:23 am
The first step is to make the TC1 compatible with the OSHW firmwares. You can update the firmware of the management MCU U4 (https://github.com/atar-axis/tc1-u4) or replace it with a simple circuit (https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/TC1-Mod.pdf).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 21, 2021, 01:30:17 pm
Talking about TC-1 and clones, a new T7 arrived. A different 324PA layout/numbering and box (and the un_labeled timing microcontroller is not placed at U5, so I don't know whether it would be compatible with the official firmwares) and smaller battery. Picture attached for reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 21, 2021, 01:51:58 pm
The new MCU above U5 seems be an alternative for U5 (STC15L104W, TC1: U4), possibly to deal with the chip shortage. So the hardware mod should still work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 21, 2021, 04:02:13 pm
At least the new T7 has an SS210 for the HV diode that used to burn on the traditional TC-1 and clones. And I also notice the new power/timer MCU has its own crystal, and the battery arrived charged. So I'll study this design a bit to see whether it's a real improvement, or basically a workaround.

Just to check: if the last line on the 324pa is "2120G1P" means manufactured in 2021, right?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 21, 2021, 05:43:39 pm
Yep, year 2021, week 20, lot G1P.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 22, 2021, 07:47:21 pm
Preliminar findings  :-DMM:
On the old model (unmodified STC15, powered on when connecting the battery) there is a whine noise and high current when using not_so_low shunt. When using the lowest shunt, it registers around 280mA under functioning and 0.24mA during standby.
On the new model (new power MCU, powered off when connecting the battery) the circuit uses around 200mA when working (no whine with the DMM), and 3.6µA during standby.

So, somebody made some improvements. Perhaps read this thread?  ;)

The main catch is still using a 324pa. Looking forward for the 64k version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ricktendo on December 24, 2021, 06:22:54 am
Will somebody be so kind as to share your mega328_color_kit 16MHz Makefile with me, trying to get it under 90KB with as much features as possible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on December 24, 2021, 09:08:59 pm
I have the standard one, orange solder resist, mint green backlit dot matrix display:

# Why do some LEDs only show as capacitors?

# Why do small inductors (20-90uH) only show as resistors?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: rsjsouza on December 25, 2021, 01:45:26 am
If the LED forward voltage is too high, the diode part will be an open circuit and the capacitance will be dominant. The tester will measure that.

When a very small inductor is measured in low frequency, its series resistance will be dominant. The tester will measure that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 25, 2021, 07:04:20 am
Why do small inductors (20-90uH) only show as resistors?
Install the latest K-firmware or M-firmware on your device and you can measure fine inductances from 50-100nH(NanoHenry) accurately enough. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 25, 2021, 12:04:07 pm
The normal inductance measurement of the OSHW firmwares can measure down to 20 or 10 µH when the tester/clone doesn't cheap out on components. The firmware measures inductance only after a resistance is detected. If the inductance measurement fails the tester assumes that the DUT is a resistor. The k-firmware supports an additional measurement method for low value capacitors and coils, called SamplingADC (requires a small reference cap in parallel with the coil). And the m-firmware supports an optional LC meter frontend (similar to the PIC based LC meters) to measure down to fF and nH.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 25, 2021, 06:28:00 pm
As promised a few pages back, here are some inverted_color_numbers [1,2,3] bitmaps to be integrated on next releases as an optional way for enhanced readability of the components_pins displayed (on ctesters with enough memory).

EDIT: Currently developed: 6x8, 8x8, 10x16, and 12x16 (all hf).

That's going to be UI_PROBE_REVERSED in the next version. If you like to create the character bitmaps for the other fonts too, be my guest. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 25, 2021, 10:36:32 pm
So far I only have figured out the encoding of the hf fonts. I haven't invested so much time on the other types of fonts. If there is any other hf pending let me know, as I developed a pseudo-automatic method for reversing the colors of those.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 26, 2021, 09:34:04 am
I've converted your 'hf' bitmaps for 6x8, 8x8, 10x16 and 12x16 into the other formats of the same sizes. Other fonts in 'hf' format are font_16x26_hf.h and font_8x16_win1251_hf.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on December 27, 2021, 06:30:02 am
If the LED forward voltage is too high, the diode part will be an open circuit and the capacitance will be dominant. The tester will measure that.

When a very small inductor is measured in low frequency, its series resistance will be dominant. The tester will measure that.

But the led lights up
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on December 27, 2021, 11:54:07 am
But the led lights up
You can show an image on your display or write what is not shown. My example :
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 27, 2021, 12:54:32 pm
The diode check is a little bit more complex than you might think. Several measurements are done to filter out other components which exhibit similar behaviour. There can be fringe cases in which a filter fails and the DUT is wrongly dedected as a diode or vice versa. For example, one of those filters checks if the forward voltage is between 0.15 and 4.64 V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 27, 2021, 01:44:18 pm
That's going to be UI_PROBE_REVERSED in the next version. If you like to create the character bitmaps for the other fonts too, be my guest. ;)
Here, the reversed_colors [1,2,3] numbers of the horizontally_flipped bitmaps, to be integrated on next releases as an optional feature for enhancing readability of the components_pins displayed on ctesters with enough memory for this. I also attach a sample of how I imagine it would look like on a monochrome display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 27, 2021, 02:14:18 pm
I would remove the circle from the element images. On a low resolution display, these circles are distorted and look clumsy.Still, they don't carry any useful information. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 27, 2021, 02:45:59 pm
You've got a point there!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 27, 2021, 08:51:55 pm
I would remove the circle from the element images. On a low resolution display, these circles are distorted and look clumsy.Still, they don't carry any useful information. ;)
Do you mean the circle around some symbols?
The icons of my previous picture are the 30x32. There is also the 24x24 and 32x32 (I haven't rendered those). For low_res displays it's very importante to balance the font_size and the symbol_size. As you suggest, the circle could be removed, and the size of the symbol be increased. This could be pondered and added as an option too :-\
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 28, 2021, 07:16:39 am
Do you mean the circle around some symbols?
Yes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on December 29, 2021, 09:38:54 am
Hi all.
I am testing the new features of the firm v1.45m on a GM328 color kit.
But there are some functions that do not appear in the menu, I do not know if they should really appear in it or not.
#define HW_BUZZER, this function does not appear in the menu, I understand that without appearing it would work having the meter modified with a buzzer, a modification that I will make shortly.
#define UI_THREE_PROFILES, this other one does not appear in the menu, besides not knowing what use it has.
I would ask for a little guidance on it.
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 29, 2021, 10:13:33 am
HW_BUZZER is a simple hardware option which is used by SW_CONTINUITY_CHECK. It's kept separate because other functions might use it in the future too. UI_THREE_PROFILES adds a '#3' to the load/save menus.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TERRA Operative on December 29, 2021, 03:39:39 pm
Question for the gurus here..

I have an LCR-T4-H (Green backlit monochrome display, yellow solder mask) that shows 'MTester v2.68 by Efan & HaoQixin/91make.taobao.com' on the initial screen.

Does anyone know of a newer firmware for this unit?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 29, 2021, 07:01:09 pm
The latest OSHW firmwares: k-firmware 1.13k or m-firmware 1.45m
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 30, 2021, 05:30:12 pm
I would remove the circle from the element images. On a low resolution display, these circles are distorted and look clumsy.Still, they don't carry any useful information. ;)

What do you think about adding small pin designators, like B, C and E for a BJT?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 30, 2021, 05:34:11 pm
This is convenient, fast and clear, of course, as long as these small symbols are distinguishable on the different types of displays. :)
Will this be in addition to numbers 1-2-3 or instead of them?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 30, 2021, 05:58:44 pm
I would add them to the symbol (after removing the circle there's free space for them). So it would be pin designators as part of the symbol  plus the pin numbers around the symbol.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 30, 2021, 06:19:41 pm
I like that option! Although we are gradually coming to the same optimal variant of symbols representation, which is used in k-firmware :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 30, 2021, 07:01:34 pm
Nothing wrong with that! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: lotec25 on December 30, 2021, 08:16:52 pm
The first step is to make the TC1 compatible with the OSHW firmwares. You can update the firmware of the management MCU U4 (https://github.com/atar-axis/tc1-u4) or replace it with a simple circuit (https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/TC1-Mod.pdf).

Ok i have my LCR-TC1 update to new firmware. Can someone please point me to what is needed to upgrade the hardware? The Dial Encoder etc?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 30, 2021, 08:35:45 pm
Please see section 2.2.5 of https://github.com/kubi48/TransistorTester-documentation/blob/main/pdftex/english/ttester.pdf for adding a rotary encoder.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 30, 2021, 11:54:02 pm
I would add them to the symbol (after removing the circle there's free space for them). So it would be pin designators as part of the symbol  plus the pin numbers around the symbol.
If we take a "clear enough" NPN symbol, we should distinguish B,C,E without need for more clues. Anyways the most important thing is to know which number is which termination, like 123=BCE, or 1=B, 2=C, 3=E, or something like that.

On the other hand, if we remove the icon circle, we could increase the figure_size within the same symbol_size, therefore perhaps it would be easier to identify BCE that way, or indeed the letters can be added to the symbols itself.

So, if I get correctly what you mean, as a picture worth thousand words, with the attached you can imagine some options we may have.

(PS: BTW I realize the arrow of the NPN should be a tad down-right on the currently used symbols).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 31, 2021, 07:42:40 am
Feliciano, I've shown before how large symbols can look without a circle. Adding the B-C-E designations to them is not difficult. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on December 31, 2021, 11:08:17 am
Hi all.
I intend to build the "RingTester" circuit.
I want to put a female connector on the GM328 Color Kit itself, and a male connector on the "Ring tester" circuit.
In order to be able to put and remove the circuit according to my needs. And simply connect the component to be measured in DUT.
My question is:
Where the "4-Counter" and "2-Pulse IN" terminals should be connected on the GM328.
And in this case of a detachable circuit, whether or not I have to put the 680ohm resistor R1.

And if I'm not mistaken the best option for the GM328 Kit Color is to use the test leads as hardware is limited.

I ask for a little explanation and guidance.

Thanks
Happy New Year to everyone   :popcorn: :popcorn:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 31, 2021, 12:15:22 pm
The GM328A has a dedicated counter input already (PD4). I haven't tested using one of the probes as pulse output (RINGTESTER_OUT), but I think you can simply use one of the Rl pins of R_PORT. So for probe #1 you would set RINGTESTER_OUT to PB0 (same as R_RL_1), RINGTESTER_PORT to PORTB and RINGTESTER_DDR to DDRB. And you wouldn't need the additional 680 Ohms resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 31, 2021, 12:25:05 pm
On the other hand, if we remove the icon circle, we could increase the figure_size within the same symbol_size, therefore perhaps it would be easier to identify BCE that way, or indeed the letters can be added to the symbols itself.

That's another reasonable idea! Let's see what other users think about a revamp of the symbols.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on December 31, 2021, 04:44:56 pm
[attach=5][attach=5]
That's another reasonable idea! Let's see what other users think about a revamp of the symbols.
On my ILI9341 it turns out like this:
Title: Re: $20 LCR ESR Transistor checker project
Post by: TERRA Operative on January 01, 2022, 05:36:07 am
The latest OSHW firmwares: k-firmware 1.13k or m-firmware 1.45m

Ok, I'm completely lost with all this stuff. I think I'll just leave well enough alone, not really worth it to me to spend hours figuring it all out just for some cheap ebay trinket.
Thanks anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 01, 2022, 11:32:59 am
You could try the ready-to-burn k-firmware for the T4. For older models use https://github.com/kubi48/TransistorTester-source/tree/master/trunk/mega328_T3_T4_st7565, and for newer ones https://github.com/kubi48/TransistorTester-source/tree/master/trunk/mega328_T4_v2_st7565.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TERRA Operative on January 01, 2022, 04:24:04 pm
Thanks, that does make things easier... How do I know if I have a new or old version?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 01, 2022, 04:37:21 pm
Simply try the first firmware. If you don't see any output on the display flash the second one. They use different pinouts for the display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on January 01, 2022, 11:14:45 pm
Does a curve tracer option exist in this sea of firmwares? That would be nice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on January 02, 2022, 03:05:53 am
If the graphics are clear enough on and around the symbol, some screen space and visual noise could be saved by removing the redundant line of text/glyphs then?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 02, 2022, 01:06:44 pm
Does a curve tracer option exist in this sea of firmwares? That would be nice.

No, the circuit doesn't support that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 02, 2022, 01:17:50 pm
If the graphics are clear enough on and around the symbol, some screen space and visual noise could be saved by removing the redundant line of text/glyphs then?

We could make the classic pinout an option, but the freewheeling diode is not part of the symbol.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on January 02, 2022, 02:31:22 pm
Does a curve tracer option exist in this sea of firmwares? That would be nice.

No, the circuit doesn't support that.
Trully the circuit "as is" doesn't support that. But what if we suppose we have enough memory -or a dedicated firmware fork is created for this purpose for the higher resolution displays-, AND we add an external RC integrator to PWM output(s), tuned to the sampling speed? That way some rough IV curves could be slowly plotted for the <6mA range (at least some guy already did that with an Arduino). What do you think?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 02, 2022, 03:52:32 pm
I know, curve tracers are a hot topic, but the Transistortester isn't designed for that. How useful would be a curve tracer with a driving capabilty of just up to 5V and 7mA? This isn't sufficient, not even for a small signal BJT like the BC548.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 02, 2022, 03:59:06 pm
Coffee is made by a coffee maker, transistor curves are drawn by a special Curve Tracer, and the device in question already has a surplus of functions and options. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rsjsouza on January 02, 2022, 08:57:29 pm
I know, curve tracers are a hot topic, but the Transistortester isn't designed for that. How useful would be a curve tracer with a driving capabilty of just up to 5V and 7mA? This isn't sufficient, not even for a small signal BJT like the BC548.
I agree with you, although a very popular curve tracer (DCA75) does not go much further than that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on January 10, 2022, 03:39:54 am
I am having a problem with a new GM328A (red pcb) kit. I build an identical one successfully previously, and also have a blue pcb pre-assembled with SMD working fine; including upgrading crystals and firmware on the blue board.

This new red one will not complete self test as it doesn't see a 220nf cap as > 100nf using the stock 1.12K firmware (reports 0nf during calibrate).  Putting in something very large gets it through the self test but then all caps are metered very low. (100nf is < 50nf, 220nf is < 140nf). All tests perfect in the other self-assembled red board.  Due to this it also messes up other tests like a NPN shows up as a FET or something.

I pre-tested every resistor, and retested every one between the good red pcb and the bad red pcb now in circuit. The only thing I haven't done is pull all the caps and test them.  I made sure the 3x each 680R and 470K resistors were all identical resistance before installing.

When I swap the ATMEL328P between boards the problem stays with the main board so it's not a damaged microcontroller.   Before I pull all the caps any other stuff to test out of circuit, does anyone have any ideas what I should concentrate on?

I tried multiple firmware alternatives and 3 different clock speeds to match the firmware (thus the angled crystal leads--but this all failed when I started with the original 8 MHz soldered directly as well.) and all exhibited similar calibrate and testing problems.

Thanks in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on January 10, 2022, 07:08:57 am
I am having a problem with a new GM328A (red pcb) kit.
I had a similar issue when upgrading from 1.12k to 1.13k. The problem is in the 7550 and the capacitance of 10 microfarads, to the right of the crystal. Change the 7550 or match the indicated capacitance with a large ESR within> 3 ohms
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 10, 2022, 07:29:28 am
I am having a problem with a new GM328A (red pcb) kit.
In this topic and the author's manual repeatedly reiterated condition, which solves 99% of all problems with measurements and calibration, replacement of the weak Chinese +5V regulator to a QUALITY (MCP1702, LP2950)!
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on January 13, 2022, 01:17:11 am
In this topic and the author's manual repeatedly reiterated condition, which solves 99% of all problems with measurements and calibration, replacement of the weak Chinese +5V regulator to a QUALITY (MCP1702, LP2950)!

I had a similar issue when upgrading from 1.12k to 1.13k. The problem is in the 7550 and the capacitance of 10 microfarads, to the right of the crystal. Change the 7550 or match the indicated capacitance with a large ESR within> 3 ohms

I swapped the capacitor, the 7550 and the TL431 between boards and the problem stayed with the board. I then replaced them all with other parts and the problem again stayed with bad board and the good board still worked fine with parts from the bad board.

Any other ideas as to the source?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on January 13, 2022, 04:10:02 am
Any other ideas as to the source?
Compare the selftest run on your boards with the picture:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on January 13, 2022, 12:00:12 pm
Any other ideas as to the source?
Besides the Atmega or the ZIF socket (it can be bypassed for tests), other user found a bad PCB with a tiny shortcircuit among traces, and we have found some shorted ceramic capacitors too (SMD and/or through-hole).
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on January 13, 2022, 04:47:20 pm
As stated in the original post, ATMEGA was swapped between boards and problem stays with board; the microcontrollers are healthy in the other board.

ZIF socket bypassed for SMD pad but same results.  Show 0 ohm continuity between all pad and zif pins as well no cross shorting there. 

All resistors measured in circuit with ATMEGA removed and show in spec and same between boards within ~1%. 


Edit: I pulled every transistor (except the LED one ) and every capacitor and tested and swapped between boards. Still same problem that always stayed with the bad board.

Could not see any damaged/shorted traces anywhere.  Metered for shorts in the microcontroller socket and ZIF and found nothing.  I'll do a bit more digging then get config data.  Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 15, 2022, 03:50:21 pm
Could not see any damaged/shorted traces anywhere.  Metered for shorts in the microcontroller socket and ZIF and found nothing. 
Remove the SRV5-04 and 6V8 protection elements temporarily. Check the operation of the tester without them. If the problem persists, show the results of the T1-T7 hardware tests.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 06, 2022, 07:43:44 pm
I've updated the comparison table for the most popular clone models. Several new models have been added as well as more information about the color palette of the displays. Fixed minor bugs and minor changes in description. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 08, 2022, 09:43:03 pm
Hello  Yuriy_K
I tried to test your "ST7735_RGB_en16MHz-Version" with a GM328A. The board is original with a 16MHz-Quartz. Fuses are (low=0xF7; high=0xD9; ext=0xFC). But the  result is only a lighted LCD. Have you made any changes in the hardware, needing other fuses?

Best wishes
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 09, 2022, 04:37:35 am
Have you made any changes in the hardware, needing other fuses?
Firmwares from page 277 are tested on the displays shown on the same page and earlier. If you have a different display, show its large image. Fuses in the picture.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 09, 2022, 03:26:57 pm
Hello  Yuriy_K,
I tested your firmware ST7735_RGB_en16MHz again with changed ext. fuse, - low fuse and high fuse are the same as before and in your posted picture. When I start the tester only the backlight of LCD switched on. Nothing others happens. As you can see: board is GM328A-kit and LCD is with ST7535 driver. I think, your vers. of firmware is based of K-H Kuebbeler's firmware. I wonder, when I flashed firmware 1.13k, all is ok. What could be the reason for this mistake? Curiously is, after starting the tester, led goes on - but by pressing the knob short or long - led and LCD staying on.

Best wishes
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 09, 2022, 05:15:56 pm
You yourself confused me. You are trying to run my firmware from page 291. This firmware is after last changes by Karl Heinz, I don't know how it works on old GM328A. Try the firmware from page 277 ST7735_RGB_en.zip it is 16MHz. She should definitely work.
Read the next steps on page 292.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 10, 2022, 06:22:54 pm
Hello Yuriy_K
R8 and R9 are checked (32,9k and 3,29k) are testet, Q1 not desoldered and testet. Your firmware "ST7735_RGB_en_kit_16MHz" testet with fuses (l=f7; h=DC; ex=FC).
After starting such strips appeared in blue later white than red, finalla was displayed "not calibrated". When I put a m328 with firmware 1.12k or 1.13k - tester operates normaly. I have no  explanation for it.
Have you or another one a solution

Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 11, 2022, 04:18:14 am
Have you or another one a solution
Send a Makefile from the firmware that works correctly. Show the image on the display in the normal connection of the display to the board.
Solder the same capacitors in parallel with the 10 uF electrolytic capacitors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on February 11, 2022, 12:29:32 pm
Hello Yuriy_K
R8 and R9 are checked (32,9k and 3,29k) are testet, Q1 not desoldered and testet. Your firmware "ST7735_RGB_en_kit_16MHz" testet with fuses (l=f7; h=DC; ex=FC).
After starting such strips appeared in blue later white than red, finalla was displayed "not calibrated". When I put a m328 with firmware 1.12k or 1.13k - tester operates normaly. I have no  explanation for it.
Have you or another one a solution

Hi Rober!
Did you change the quartz from GM328? I know the original is 8MHz, the software version you want to use is compiled for 16MHz. Maybe that's where the problem lies.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on February 11, 2022, 12:37:19 pm
Hello colleagues.

With some delay, for which I apologize, I am posting the Romanian language file, updated and functionally verified, for ver. 1.45m
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 11, 2022, 02:18:10 pm
@ Yuriy_K
the makefile is from 1.13k; output to lcd is the same as before. Sorry, which caps in parallel to which 10µF?

@ Dumidan

The quarz was changed a long time ago to 16 MHz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 11, 2022, 04:08:09 pm
Sorry, which caps in parallel to which 10µF?
In your diagram, there are two of them (indicated by red arrows) soldered to them in parallel. At the end of the previous page, I wrote that when installing version 1.13k, it is necessary to adjust the electronic components. it is necessary to replace the 7550 and select the capacitances of these capacitors. This is due to the large current at a frequency of 16 MHz (against 8 MHz) and a slightly higher load on the processor due to color switching commands.
Judging by the fact that "?" is displayed correctly, the software is installed correctly and it is only necessary to restore the normal operation of the TTester by hardware.
I compared the files, everything needs to be corrected "hardware".
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 11, 2022, 06:23:22 pm
The 7550 is replaced by mcp1702 long time ago also changed TL431 to LT1004; caps of 100n in parallel to both electrolyt caps are already installed during construction; 10µf cap near quarz changed by one with ESR > 3 ohm - I had only one with 10µF and low height. The result is displayed on cld the same as before.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 12, 2022, 03:16:19 am
Your situation is similar to the GM328A with the BGR gamut, where the display does not allow you to transfer the TTester to 16MHz. The attached picture shows an image with such a quartz. Try to choose the parameters of the stabilizer and blocking capacities yourself. Try replacing the 1702 with a more powerful LM1117 and increasing the blocking capacitances to 47uF. There is nothing more I can do to help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 12, 2022, 05:45:30 pm
Hello Yuriy_K
I had today more time and tested both versions ST7735_BGR from page 277 and got an output. But this is mirrored and stands on head. After test routine is indicaded a value of about 60 pF without any component in test socket(without adjust).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 12, 2022, 10:14:00 pm
If your screen is horizontally and/or vertically flipped, and if you build your own firmware, you can define the screen orientation according to your needs. For instance, for the m-firmware:
Code: [Select]
//#define LCD_FLIP_X                      /* enable horizontal flip */
#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_ROTATE                      /* switch X and Y (rotate by 90°) */
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 13, 2022, 04:01:33 am
But this is mirrored and stands on head. After test routine is indicaded a value of about 60 pF without any component in test socket(without adjust).
Hello  Rober
On the current page there is a picture with the results of selftesting. Compare with your results and show the difference. The RGB and BGR firmware differ only in the preset colors for the displayed elements. In all other respects they are the same. Decide which firmware works for you and send the picture to flip and mirror it no problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 13, 2022, 11:13:36 am
Hello Yuriy_K
it's a little bit difficult to make the selftest with mirrored  presentation. I dont know, where in the program I can do changes to flip vertically and horizontally lcd. In firmware of madris it is in config.h , but in k-version it is not descripted and I don't have your version of firmware to do any changes in h- or c-files. After then, with a normal presentation  I'll do the selftest
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 13, 2022, 12:49:39 pm
In order to change the screen orientation of a GM328: on the the m-firmware you use the config_328.h file, on the k-firmware you use the makefile of the mega328_GM328 folder. Then you "make" the firmware and test.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 13, 2022, 02:57:35 pm
After then, with a normal presentation  I'll do the selftest
See the firmware in your personal mail.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 13, 2022, 03:02:03 pm
Hi Feliciano
One of my testers is using k-firmware and the other m-firmware. Both testers work fine. Now I'm going to test the modified color firmware of Youriy_K - it is a modified k-firmware and it looks like an output of testers with mega644. It looks like very nice and I wanted test it. The only published files are -.hex, -.eep and makefile. To compile I'm need the changed and/or modified files.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 13, 2022, 03:09:58 pm
Thank you so much, just I found your mail and will test now
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 13, 2022, 03:32:16 pm
All three versions are standing on head.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 13, 2022, 05:32:50 pm
All three versions are standing on head.
Try the following option from personal mail
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 13, 2022, 09:59:50 pm
Hi Yuriy_K
Unfortunately all three versions are flipped  horizontally and  for 8 MHz not necessary, because no tester with 8MHz-quarz
Title: Re: $20 LCR ESR Transistor checker project
Post by: ricktendo on February 14, 2022, 04:32:54 am
All three versions are standing on head.
Try the following option from personal mail
Would you be so kind as to share your makefile for the mega328_color_kit with me too?

I would like to compare to mine and see if I can get as many features as possible and have it fit the flash.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 14, 2022, 07:03:28 am
Would you be so kind as to share your makefile for the mega328_color_kit with me too?
I know several different modifications of the ST7735 that require customization of my sources. To increase the number of menu items for the 328 processor, I removed or replaced some of the Karl-Heinz approaches. For this reason, the sources are not transferred. You need to create a working version on the latest version 1.13k yourself and send me the Makefile or try my firmware from page 277. Based on the results of these tests, i can understand what changes need to be made and the source texts for your display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ricktendo on February 14, 2022, 01:07:17 pm
I do not have one for 1.13k but I do have one for 1.45m, these are the modifications I make.

Code: [Select]
cd TransistorTester-source/trunk
sed -i -r 's/\#CFLAGS \+\= \-DNO_FREQ_COUNTER/CFLAGS \+\= \-DNO_FREQ_COUNTER/' ./mega328_color_kit/Makefile
sed -i -r 's/\#CFLAGS \+\= \-DPAGE_MODE/CFLAGS \+\= \-DPAGE_MODE/' ./mega328_color_kit/Makefile
sed -i -r 's/CFLAGS \+\= \-DFONT_8X12thin/\#CFLAGS \+\= \-DFONT_8X12thin/' ./mega328_color_kit/Makefile
sed -i -r 's/\#CFLAGS \+\= \-DFONT_8X16thin/CFLAGS \+\= \-DFONT_8X16thin/' ./mega328_color_kit/Makefile
sed -i -r 's/CFLAGS \+\= \-DBIG_TP/\#CFLAGS \+\= \-DBIG_TP/' ./mega328_color_kit/Makefile
sed -i -r 's/\#CFLAGS \+\= \-DINVERSE_TP/CFLAGS \+\= \-DINVERSE_TP/' ./mega328_color_kit/Makefile
sed -i -r 's/\#CFLAGS \+\= \-DNO_TEST_T1_T7/CFLAGS \+\= \-DNO_TEST_T1_T7/' ./mega328_color_kit/Makefile
sed -i -r 's/\#CFLAGS \+\= \-DWITH_XTAL/CFLAGS \+\= \-DWITH_XTAL/' ./mega328_color_kit/Makefile
sed -i -r 's/\#CFLAGS \+\= \-DWITH_UJT/CFLAGS \+\= \-DWITH_UJT/' ./mega328_color_kit/Makefile
sed -i -r 's/\#CFLAGS \+\= \-DWITH_PUT/CFLAGS \+\= \-DWITH_PUT/' ./mega328_color_kit/Makefile
sed -i -r 's/OP_MHZ \= 8/OP_MHZ \= 16/' ./mega328_color_kit/Makefile
sed -i -r 's/\#CFLAGS \+\= \-DNO_LONG_PINLAYOUT/CFLAGS \+\= \-DNO_LONG_PINLAYOUT/' ./mega328_color_kit/Makefile
sed -i -r 's/CFLAGS \+\= \-DANZ_MESS\=25/CFLAGS \+\= \-DANZ_MESS\=30/' ./mega328_color_kit/Makefile
sed -i -r 's/\#CFLAGS \+\= \-DEXT_NUMERATOR\=10/CFLAGS \+\= \-DEXT_NUMERATOR\=10/' ./mega328_color_kit/Makefile
sed -i -r 's/\#CFLAGS \+\= \-DEXT_DENOMINATOR\=1/CFLAGS \+\= \-DEXT_DENOMINATOR\=1/' ./mega328_color_kit/Makefile

Main thing I want to do is increase the menu count but from downloading your makefile from 277 I think I know why mine is shorter
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 14, 2022, 01:52:34 pm
I do not have one for 1.13k but I do have one for 1.45m, these are the modifications I make.
Here is the firmware that Rober tested today.
According to him, everything works fine.
Only I do not know what changes he made to the circuit in his TTtester, except for those that are published above.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Rober on February 14, 2022, 04:36:35 pm
@ Yuriy_K.
5 years plus (your last question) . A little mistake I have seen  in both versions. When you test a FET, at the symbol are gate, drain and source labeled - but at the end of text, only gate is labeled. For drain and source stand a "?". It doesn't have to corrected - only for your infirmation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 14, 2022, 06:01:53 pm
The '?' or 'x' for a JFET's drain/source pins indicates that drain and source are symmetrical. It's not a bug, it's a feature. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: tsmith35 on February 15, 2022, 12:08:57 am
Oh, that's really interesting. Myself, I never thought about such a thing since I'm so used to silicon components having a polarity of sorts. But I see where one textbook says, "Although the JFET is a symmetrical device whose source and drain can be interchanged, it is useful in circuit design to designate one of these two terminals as source and the other as drain. The circuit symbol achieves this designation by placing the gate closer to the source than to the drain."

From a practical point of view, I can see where designating source and drain may be necessary for circuit design since component orientation could be an issue with three connection points.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 15, 2022, 01:55:43 pm
There is a way to tell source and drain for a symmetrical JFET apart, but the Transistortester can't do that. The gate-source capacitance is much lower than the gate-drain capacitance. And not every JFET is symmetrical.
Title: Re: $20 LCR ESR Transistor checker project
Post by: magic on February 15, 2022, 06:19:01 pm
Speaking of capacitance, how accurate is that pF measurement and junction capacitance reporting? Does the measurement technique provide stable/reproducible readings near zero or does it have visible zero drift like the LC100-A? Does it show any reading for less than 1pF?

Is it true that this function still only exists in K firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 15, 2022, 07:15:07 pm
Speaking of capacitance, how accurate is that pF measurement and junction capacitance reporting? Does the measurement technique provide stable/reproducible readings near zero or does it have visible zero drift like the LC100-A?

The lower limit for the normal capacitance measurement (also used for diodes and so on) is:
- k-firmware: 25 pF
- m-firmware: 5 pF

The meaurement can be fairly stable with a good tester (stable Vcc).

Does it show any reading for less than 1pF? Is it true that this function still only exists in K firmware?

The k-firmware offers an optional software feature called SamplingADC which allows a special measurement of low capacitance values down to a few fF. For the m-firmware there's an LC meter hardware option with a similar measurement range down to a few fF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 15, 2022, 07:41:35 pm
Does it show any reading for less than 1pF?
Is it true that this function still only exists in K firmware?
An example of measurement on 1.13k firmware and comparison of measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: magic on February 15, 2022, 08:35:37 pm
Thanks, this doesn't look too terrible. Am I to understand that 0.01pF stability is realistic with this meter?
Those cheap resonant LC meters easily drift more, even after warmup. Furthermore, mine clamps negative readings to zero, making it harder to correct for drift.

Yes, this is the mode I meant. Reading the 1.13k manual gave me impression that it's this mode which is used for junction capacitance (it even mentions testing at 0V and -5V bias), I didn't know that normal mode can be used too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dark_hawk on February 16, 2022, 04:14:47 pm
Hi,

I have an LCR-T4 tester I've bought from China ages ago and just now found out it has an original better firmware and a 300 page thread on eevblog.
I swapped the 8M crystal to a 16M and upgraded the firmware to 1.13k found on that yandex disk. And things seem better in all aspects.

I'm thinking about getting Hiland M644 or the T7 with that fancy color screen.
I have a few questions that I tried to search answers on the thread but couldn't find any.
1- What would be the extra benefits I get If I switch to one of those newer versions?
2- Which one should I get? The Hiland M644 or the T7 or another model?
3- RDSon readings of my T4 seems off. I think maybe because it's being tested with 5V instead of the 10/12 volts I usually use to get RDS.
This is made worse with mosfets that have lower gate capacitances like the IRF740B with reads 4 ohms RDS while the value using a 12v/1.6A load is around 0.5-0.6 ohm.
Are the newer versions using higher voltages when testing for RDS since it can test zeners up to 35? Or is it the still the same 5 volts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 16, 2022, 04:23:37 pm
These gadgets works with 5V for the microntroller, so your Rds measurements are with Vgs 5V. (And the ctesters able to test zeners use a divider to measure/calculate Vz).

64KB versus 32KB allows more functions to be enabled on your firmware at once, and some of those requires extra hardware (like the hardware extensions on the Hiland M644, or you can DIY).
Title: Re: $20 LCR ESR Transistor checker project
Post by: dark_hawk on February 16, 2022, 05:46:21 pm
Could you please elaborate as to the extra functionality I will get with a 64KB chip/Extra hardware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 17, 2022, 12:18:58 pm
I mean, more things enabled on your own particular firmware build.

There are plenty of features you can choose from. You can look at the config files of the m-firmware or the makefile of the k-firmware for grasping how many (similar or different) features each one has to offer.

Every function uses memory, some more, some less. A larger font user more flash, and a color screen requires more code than a monochrome screen (and deppends on the particular controller), etc.

Let's take one example: to show the E12 or E24 or E96 standard values next to a resistor measurements, so you can say whether the particular piece you're measuring is within range or not. Of course E96 with colour codes will use more memory than E12 only text. You can also choose to show standard values for capacitors.

Another example: there is an option to monitor DUT placed between Terminals 1 and 3. You can monitor L, or C, or R, or R and L, or R and C, or R, L, and C. The memory requirements are different.

So maybe somebody wants to enable every single feature the m-firmware or k-firmware has. I don't whether 64KB of flash will suffice for that, neither I know whether the RAM would it be enough too. Also keep in mind some features requires extra hardware.

Bottomline: me and others look at the source code, check which things like better than others for our job/hobby, make the file, check whether fits our unit or not, until we find the best tailored binaries for our likings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: faustino on February 19, 2022, 12:54:11 am
Hi everybody
Right now where can i find the Hiland M644 online? In Banggood it says its in backlog.
Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 22, 2022, 06:38:26 am
Measurement example of a MOSFET transistor rarely encountered depletion type
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 23, 2022, 04:42:55 pm
Does anyone knows the maker of the attached Zener? (The 6P2's logo resembles General Semicondutor, but I don't think it is).
I would ask the same for the V05, but I don't notice a logo  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 23, 2022, 04:55:37 pm
SML4735 - ZENER 6.2V
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 23, 2022, 05:03:25 pm
Thanks for the reply indman.

So do you think it's a Vishay (formerly General Semiconductor)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 23, 2022, 05:07:11 pm
The original manufacturer is Vishay and what is installed on your board is made in China! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 23, 2022, 05:39:15 pm
Exactly! that's why I was asking whether the real maker can be guessed from the not-so-alike logo (to look for a better-matching datasheet and/or an improved aftermarket part, TVS vs Zener, etc.).
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on February 25, 2022, 01:41:05 pm
Hello guys. I have the LCR-T4 with stock firmware version 2.07

I would really like the in-circuit ESR measuring function so I want to update the firmware.
I know the m firmwares are for compiling yourself and k firmwares are precompiled.
I intend to use the mega328_T3_T4_st7565 k-firmware. But in the subfolder I also see a Makefile.

I know how to program an ATmega chip using avrdude with .hex files but the Makefile is confusing.
Do I have to use the Makefile?
Or is it sufficient to upload the .hex and .eep files to the chip using avrdude itself?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 25, 2022, 02:20:53 pm
You just need to program the .hex and .eep file. The Makefile is meant for compiling the firmware yourself if you want to (comes with the correct settings for the specific tester model).
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on February 25, 2022, 03:35:51 pm
You just need to program the .hex and .eep file. The Makefile is meant for compiling the firmware yourself if you want to (comes with the correct settings for the specific tester model).

Thank you.
I flashed it and I see a nice new firmware now with the additional functions available.  :-+

A few questions tho:
1- It takes a bit longer to start up and to make measurements, is that normal?
2- It doesn't turn off automatically anymore, it appears that it is constantly making measurement. Do I have to do something to turn it off? Also is it okay to swap the element in it while it's still showing the previous element measurements?
3- I didn't touch the fuses. Do I have to change them? They read as follows:
Code: [Select]
avrdude: safemode: lfuse reads as FF
avrdude: safemode: hfuse reads as D7
avrdude: safemode: efuse reads as F9
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 25, 2022, 04:19:33 pm
If it's just a bit longer it should be fine since the OSHW firmware usually checks more things than any modified one. Please see Karl-Heinz' excellent documentation for usage details (https://github.com/kubi48/TransistorTester-documentation). When the output of the current DUT is done you can swap the DUT. The fuse bits seem to be ok (though, lfuse should be 0xf7 for a quartz crystal).
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on February 25, 2022, 06:16:24 pm
If it's just a bit longer it should be fine since the OSHW firmware usually checks more things than any modified one. Please see Karl-Heinz' excellent documentation for usage details (https://github.com/kubi48/TransistorTester-documentation). When the output of the current DUT is done you can swap the DUT. The fuse bits seem to be ok (though, lfuse should be 0xf7 for a quartz crystal).

I read that but I'm still confused by the tester's behavior:

When I put the component in pins 1&2 :
- Battery voltage is not shown at the bottom of the result
- An indication letter (like [R]) is not shown at the top right of the screen
- After making a measurement, the tester turns off automatically after ~25 seconds
- After making a measurement, if I press the button a new measurement will be performed
- After making a measurement, a new measurement is possible by replacing the component and pressing the button once
- When I put in a capacitor a single measurement result is shown (result is not constantly updated)

However when I put the component in pins 1&3 or 2&3:
- Battery voltage is always shown at the bottom of the result
- An indication letter (like [R]) is shown at the top right of the screen
- After making a measurement, the tester does not turn off automatically
- After making a measurement, if I press the button once nothing happens. If I press the button again the tester turns off.
- After making a measurement, a new measurement is not possible as pressing the button has above behavior. Also putting a new part causes bugous behavior because the tester is not expecting a new part.
- When I put in a capacitor the results are constantly updated, I can tell because the ESR value keeps changing roughly every second.

I don't know if this is intended behavior or if I made a mistake somewhere.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 25, 2022, 07:32:33 pm
Just in case: it's not the same to start your ctester with a long press of the button or a short press of it. In one case it can "stay on", and the other it could "auto power off". Anyways you can check that part on the makefile (k-firmware) or the config file (m-firmware).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Enlargee79 on February 26, 2022, 03:39:28 am
Hello all.

This is a gargantuan thread; I've skimmed through quite a few pages but I can't find any n00b friendly summaries or recommendations.

I would like a component tester for simple DIY/hobby/basic repair use cases, and I don't need any Dave style super high-level features. Simple component identifiaction and basic functionality testing would be more than enough for my needs.

Since these things have evolved quite a bit since ~2013 (or even earlier), does anyone have a recommendation for simply getting started, or a general overview of features? I've seen GM328/Mega328's and the original LCR-T4 style that Dave reviewed in a video, but I'm not sure which of these to get or whether something else would be more appropraiate.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on February 26, 2022, 09:53:30 am
Just in case: it's not the same to start your ctester with a long press of the button or a short press of it. In one case it can "stay on", and the other it could "auto power off". Anyways you can check that part on the makefile (k-firmware) or the config file (m-firmware).

I read that in the manual but it doesn't make any difference for me.
The only thing that makes a difference is if I insert the component in pins 1&2 or not.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 26, 2022, 10:56:48 am
Since these things have evolved quite a bit since ~2013 (or even earlier), does anyone have a recommendation for simply getting started, or a general overview of features? I've seen GM328/Mega328's and the original LCR-T4 style that Dave reviewed in a video, but I'm not sure which of these to get or whether something else would be more appropraiate.

Please see https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf for a list of Transistortester clones.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 26, 2022, 11:24:25 am
The only thing that makes a difference is if I insert the component in pins 1&2 or not.

The other pins trigger a special measurement mode. Please see chapter 1 'Features', item 30!
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on February 26, 2022, 05:35:17 pm
The only thing that makes a difference is if I insert the component in pins 1&2 or not.

The other pins trigger a special measurement mode. Please see chapter 1 'Features', item 30!

Ah that must be it!
Thank you very much for your help and for your work on the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Enlargee79 on February 27, 2022, 12:03:38 pm
That is exactly what I was talking about. It would be great if the OP could add a link to this in the first post.

Thank you kindly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Tekjive on February 27, 2022, 02:30:46 pm
Anyone know the difference between the LCR-T7 vs the T7-H?

@Enlargee79 I’ve narrowed my choice between these 2 as they have the most info per reading, are as accurate as you can get in this price range, etc. they are basically all the same when compared on that chart but the fact this model gives the RDS spec of mosfets is the selling point for me as I want to be able to group similar rated mosfets in same bank.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 27, 2022, 04:03:05 pm
R_DS is a feature supported by both OSHW firmwares. If your clone doesn't do R_DS simply flash one of the two OSHW firmwares. BTW, TC1, T7 and family come with an additional control MCU (kind of lock-in) which can be flashed with an alternative firmware or replaced with a simple two-transistor circuit to make it compatible with the reference design.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on February 28, 2022, 11:41:53 am
Does anyone know how the ring tester external circuit is supposed to be wired?
I see a "counter" and a "pulse in" pin and also another "counter" at the right and I'm not sure where I should connect these.

(https://i.imgur.com/V2VC1At.png)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 28, 2022, 01:07:39 pm
It's explained in the m-firmware's README file. 'Counter Out' has to be connected to the ATmega's T0 pin and 'Pulse In' either to a dedicated pin or to probe #2. The same for 'Vcc' and 'Gnd'. And the 'Counter' flag is just a signal name for the schematic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 28, 2022, 01:08:18 pm
Anyone know the difference between the LCR-T7 vs the T7-H?
The Display & Controller. AFAIK T7 can be made compatible with OSHW (with the required mods madires told), whereas the T7-H isn't supported.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on February 28, 2022, 02:19:05 pm
It's explained in the m-firmware's README file. 'Counter Out' has to be connected to the ATmega's T0 pin and 'Pulse In' either to a dedicated pin or to probe #2. The same for 'Vcc' and 'Gnd'. And the 'Counter' flag is just a signal name for the schematic.

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 28, 2022, 02:45:15 pm
Anyone know the difference between the LCR-T7 vs the T7-H?
The Display & Controller. AFAIK T7 can be made compatible with OSHW (with the required mods madires told), whereas the T7-H isn't supported.

The T7-H seems to come with an S6D0117 compatible display which isn't supported yet. If someone sends me a sample T7-H I would try to write a driver for the m-firmware. However, the combination of a small display and a resolution of 128x128 pixels isn't very helpful, unless you're near-sighted or wearing reading glasses.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on March 02, 2022, 10:30:39 am
@madires are the config files used to compile the k-firmware available?
I flashed the mega328_T3_T4_st7565 k-firmware successfully.
I need the ring tester function and I have to use the m-firmware but I cannot get it working. When I press the button the LCD lights up but no text is shown. I desoldered it to make sure pin numbers are correct but it appears to have 10 pins! And there are only 5 pins in the config file.
I'm lost.

Is there perhaps a debug function where I can put an LED somewhere to at least confirm that the firmware is working?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2022, 11:00:07 am
Have you tried the settings for the T3/T4 clones listed in the Clones file? There are two different pinouts for the display. For testing connect an LED to the probes, it should flicker while the component search runs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on March 02, 2022, 11:32:21 am
Have you tried the settings for the T3/T4 clones listed in the Clones file? There are two different pinouts for the display.
Which file exactly? I have the clone comparison PDF and the models PDF but they don't have the pinouts.
It's very difficult to trace the pins because of the board layout and parts being SMD and vias not always being visible. But I'm sure PD4 is connected to my display which is not listed in ST7565R section of config_328.h

Quote
For testing connect an LED to the probes, it should flicker while the component search runs.
It does flicker so hopefully the firmware is working.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on March 02, 2022, 11:53:50 am
OK I found this post https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/msg872669/#msg872669 (https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/msg872669/#msg872669) and I think I have figured the pinouts. I finally managed to get "something" into the display. Gonna play with it a bit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2022, 12:06:54 pm
Have you tried the settings for the T3/T4 clones listed in the Clones file? There are two different pinouts for the display.
Which file exactly? I have the clone comparison PDF and the models PDF but they don't have the pinouts.

The source code of the m-firmware comes with a file named 'Clones'.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on March 02, 2022, 12:16:04 pm
The source code of the m-firmware comes with a file named 'Clones'.

Ah yes. The configs are listed there and they work.
Thanks yet again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on March 02, 2022, 05:01:11 pm
I've faced another problem.
In my clone (LCR-T4) the PD4(T0) pin is connected to LCD reset.
The documentation keeps saying it can be shared with the LCD but it can't.
When I open the frequency counter or ring tester function, after a few seconds the LCD is reset and I only see a green screen until I reset the device.
 |O

Is there any hope for me?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2022, 05:21:41 pm
No surprises there! Sharing the display's reset line with another signal doesn't work, but sharing SCK or MOSI works fine. You can blame the clone designer for the poor pin assignment. As work-around you could cut the trace and hardwire the LCD's reset line via a resistor to 3.3V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on March 02, 2022, 05:59:42 pm
No surprises there! Sharing the display's reset line with another signal doesn't work, but sharing SCK or MOSI works fine. You can blame the clone designer for the poor pin assignment.

Is the reset functionality not needed at all?
It's listed as "optional" in the config file but I'm not sure how optional it is.

Quote
As work-around you could cut the trace and hardwire the LCD's reset line via a resistor to 3.3V.
Ugh that's really undesirable but I guess I have no choice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2022, 06:59:25 pm
It's nice to have the MCU control /RESET and /CS, but to save pins you can hardwire both. That's the reason why both signals are optional in the configuration. Some clones have hardwired /CS for example. However, there can be also drawbacks based on the specific pin assignment. WIth a hardwired /CS no other SPI chips can be attached to the bus, like a touchscreen controller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elepo on March 02, 2022, 07:10:38 pm
It's nice to have the MCU control /RESET and /CS, but to save pins you can hardwire both. That's the reason why both signals are optional in the configuration. Some clones have hardwired /CS for example. However, there can be also drawbacks based on the specific pin assignment. WIth a hardwired /CS no other SPI chips can be attached to the bus, like a touchscreen controller.

I see. I'll probably cut the trace then.
Mine has CS shorted to gnd.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Regina on March 05, 2022, 12:30:12 am
I, I'm new here. Not a total newb, but skills are mad rusty. A google search of the fish48840 led me here. Rather than searching the 300 pages here, can I just be lazy and ask what some common problems it may have where it will not turn on at all? It worked years ago when I bought it, but now seems dead. No electrolytic or tants in sight. What could be wrong with this thing. Not advanced enough to be updating firmware and the like. Just want to be able to use it again. I tried the test button down for the 3+ seconds, but nothing, not even backlight. Any ideas? I don't have an ESR tester and usually don't have to mess with surface mount. I mean, I guess I could if I had to, but not something I am used to. Not like lifting a lead of a cap and checking it out of circuit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 05, 2022, 11:36:07 am
Welcome to the forum! First thing to check is the power supply. When you push the test button does the voltage regulator output 5V?
Title: Re: $20 LCR ESR Transistor checker project
Post by: BDX18 on March 09, 2022, 09:52:36 am
Howdy,

I decided to get one of these testers, but based on what I saw on eBay and read here (the last 10 pages), looks to me there are many different versions, and I presume some may be better than others.

Can someone recommend me a few models that would be good buys for one reason or another?

Obviously, I want something that can be updated to the latest firmware -- that's a must.
Having a faster CPU, more memory, a better LCD or a case are all nice to have.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 09, 2022, 12:17:25 pm
Welcome to the forum.

Because there are many options available of hardware and/or firmware, I would start by looking the clone comparison chart posted on the last couple of pages (shared by indman and madires). Knowing which specs and options each hardware offers, you can narrow your choices.

And after you buy it and you're familiar with it, you can flash an OSHW firmware to further improve that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 23, 2022, 06:42:47 pm
Anyone speaking Hungarian? A user from Hungary needs some help with the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: yo0 on March 23, 2022, 07:46:29 pm
Any comments about this model?

https://a.aliexpress.com/_mOqwxsG

Best regards

Pio
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2022, 10:04:57 am
Looks like a GM328A with a nicer design. Should be fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 24, 2022, 11:04:48 am
Any comments about this model?
This model is presented in my table of clones, and photos of its internal content can be viewed in the "GM328A(BGR)1" folder on my resource https://yadi.sk/d/yW8xa5NJgUo5z   ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on March 24, 2022, 11:16:42 am
From indman's photos, it seems to have the components for extended frequency measurement and zener testing... am I right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 24, 2022, 11:34:02 am
it seems to have the components for extended frequency measurement and zener testing... am I right?
No, this clone has the same feature set as the regular GM328A
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on March 24, 2022, 07:15:01 pm
Ok, I thought these components were for the frequency measurement prescaler and zener voltage boost, but they must be for something else
[attachimg=1]
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 24, 2022, 07:28:28 pm
3 chips that are marked in red are the maintenance of the BGR display, and voltage boost are marked in red is the node for powering the tester from + 5V(USB-С,microUSB) ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2022, 07:49:08 pm
Is that setup similar to the ST7735 semi-compatible display? IIRC, that display had a level shifter and an MCU emulating an ST7735.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 24, 2022, 07:55:43 pm
madires,yes, it's 99% likely! ;) It is enough to look at the white frame of the distinctive display to understand that this is a BGR semi-compatible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2022, 08:21:39 pm
So LCD_SEMI_ST7735 might work for that new design as well. Let's wait and see.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 26, 2022, 09:56:54 pm
But I was thinking, according to indman's table of clones, that it was already supported. Isn't it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: DarthMalgus on March 28, 2022, 11:53:42 am
Hey guys, after reading a lot about these cheap testers i decided to buy one for myself. There was a post analyzing their differences and i decided to go with this "M328" from aliexpress: https://www.aliexpress.com/item/32797552392.html (https://www.aliexpress.com/item/32797552392.html)

Despite the seller pictures i received a black PCB with all SMD components but luckily the 328p processor was socketed. It looks exactly like this tester: https://www.banggood.com/GM328A-LCD-Transistor-Tester-Diode-ESR-Meter-PWM-Square-Wave-Generator-Soldered-Module-p-1384846.html (https://www.banggood.com/GM328A-LCD-Transistor-Tester-Diode-ESR-Meter-PWM-Square-Wave-Generator-Soldered-Module-p-1384846.html)

The firmware was 1.12k on it. I bought a new processor and a 20Mhz crystal and i upgraded to a 1.37m firmware version which i got online. The archive name is "AY-AT-Markus1.37En(20Mhz)" so it should work with the new crystal Found the source of this firmware after posting: https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A (https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A) (It should be compatible)

Now with the new processor and crystal the tester takes 10 seconds to boot up and everything is slow and laggy. My issue is that i don't know how to make the hex and eep files for this tester on my own. Is there a place to get the latest firmware for this clone or any guidance on how to make it myself ?
Did i miss some other important modification to make the tester work with the m-firmware or could this simply be a case of a bad processor or incompatible firmware ?

Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: theHWcave on March 28, 2022, 01:29:41 pm
My main suspect is the fuses not set correctly for external crystal operation. I think by default (new chip) the default setting is for a very slow internal oscillator.

These are settings that work for me:
fuses_lo = 0xf7
fuses_hi = 0xd9
fuses_ext = 0xfc
lock_byte = 0xff
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 28, 2022, 01:54:18 pm
The firmware was 1.12k on it. I bought a new processor and a 20Mhz crystal and i upgraded to a 1.37m firmware version which i got online. The archive name is "AY-AT-Markus1.37En(20Mhz)" so it should work with the new crystal Found the source of this firmware after posting: https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A (https://disk.yandex.ru/d/yW8xa5NJgUo5z/GM328A) (It should be compatible)
Now with the new processor and crystal the tester takes 10 seconds to boot up and everything is slow and laggy. My issue is that i don't know how to make the hex and eep files for this tester on my own.

WARNING!
All author's K- and M- firmware, which are presented for free use and download on my resource https://disk.yandex.ru/d/yW8xa5NJgUo5z, have been tested 100% in operation on 1000 and more similar devices! If the firmware on your clone does not work at all or very slowly, then this does not mean that your device is special and needs some kind of specially compiled firmware! First of all, check the correctness of the installed fuses and firmware, as well as possible options for malfunctioning the hardware stuffing. All this is discussed in detail in the author's manuals. Read carefully.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 28, 2022, 02:14:03 pm
But I was thinking, according to indman's table of clones, that it was already supported. Isn't it?

Possibly someone tested that already. I have just a few clones for testing purposes and don't know all the clones and their variants out there.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 28, 2022, 03:00:22 pm
Hello everyone,

I have a mega328_MK-328 from Electronics Studio with version 1.31M of Markus. I would like to upgrade to version 1.45M but can't remember how to create the eep and hex files needed?

Does anyone have the eep and hex files for this model they could upload (mega328_MK-328 from Electronics Studio)?

Or does Indman's repository have the 1.45m version, I seem to have checked and don't see a directory for the mega328_MK-328 ??

Thank you so much!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 28, 2022, 03:14:24 pm
Or does Indman's repository have the 1.45m version, I seem to have checked and don't see a directory for the mega328_MK-328 ??
My repository for MK-328 clone only has a working k-firmware. I did not compile m-firmware for this clone. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: PKTKS on March 28, 2022, 03:19:36 pm
Hello everyone,

I have a mega328_MK-328 from Electronics Studio with version 1.31M of Markus. I would like to upgrade to version 1.45M but can't remember how to create the eep and hex files needed?

Does anyone have the eep and hex files for this model they could upload (mega328_MK-328 from Electronics Studio)?

Or does Indman's repository have the 1.45m version, I seem to have checked and don't see a directory for the mega328_MK-328 ??

Thank you so much!

Have a look if still there the versions ..
git clone https://github.com/madires/Transistortester-Warehouse

Then just make all  in a properly setup system should be enough...

Tested again today.. holds fine

Paul
Title: Re: $20 LCR ESR Transistor checker project
Post by: DarthMalgus on March 28, 2022, 04:59:42 pm
Thanks a lot for the help and your fast replies guys!
After looking around i found a program that will set my fuses.
Here is what is currently in the chip:
[attach=1]
What do i need to change for an external 20Mhz crystal and to make the firmware work on my GM328A clone ?
Also if i manage to find a newer than 1.37m version will i need to reprogram the fuse along with eeprom and flash ?
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 28, 2022, 05:06:51 pm
theHWcave wrote to you in detail how to set the fuses correctly. Set your program to the same values.
Make sure that the new values ​​are written correctly in the program and do not touch them again, even if you have to install a more recent firmware!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 28, 2022, 05:23:33 pm
Hello everyone,

I have a mega328_MK-328 from Electronics Studio with version 1.31M of Markus. I would like to upgrade to version 1.45M but can't remember how to create the eep and hex files needed?

Does anyone have the eep and hex files for this model they could upload (mega328_MK-328 from Electronics Studio)?

Or does Indman's repository have the 1.45m version, I seem to have checked and don't see a directory for the mega328_MK-328 ??

Thank you so much!

Have a look if still there the versions ..
git clone https://github.com/madires/Transistortester-Warehouse

Then just make all  in a properly setup system should be enough...

Tested again today.. holds fine

Paul

That's the problem, I don't have a proper setup to compile the code. Any one have it already compiled? Tks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: DarthMalgus on March 28, 2022, 06:01:02 pm
It seems i can not alter the extended fuse but i got the other two to match the provided values and it works now!  :-+
I would like to upgrade it further to 1.45m but i don't know how to make the .hex and .eep files myself. I downloaded an archive and it has a bunch of files with .c and .h extensions.
Any further help would be much appreciated.
Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: PKTKS on March 28, 2022, 06:29:44 pm

That's the problem, I don't have a proper setup to compile the code. Any one have it already compiled? Tks!

Just do not blame me if the drive explode...   :popcorn:

Compiled again just now...  just fine..

Hope you know what you are doing.. your device may brick...
you need to identify things and do things by hand...


Paul  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 28, 2022, 06:57:00 pm

That's the problem, I don't have a proper setup to compile the code. Any one have it already compiled? Tks!

Just do not blame me if the drive explode...   :popcorn:

Compiled again just now...  just fine..

Hope you know what you are doing.. your device may brick...
you need to identify things and do things by hand...


Paul  :-+

Hi Paul, thanks a million. I know how to get it on the device with avrdude, I still have the .bat file I used for version 1.31m, so I'll give it a try. If it bricks, I have version 1.13k compiled that I transferred to another identical device and it works, so I'll let you know. Thanks again!
Title: Re: $20 LCR ESR Transistor checker project
Post by: PKTKS on March 29, 2022, 09:18:38 am
OK just care to not brick your device...

Paul
Title: Re: $20 LCR ESR Transistor checker project
Post by: wizard1 on March 30, 2022, 06:05:46 am
Moving to 1.45m on an AY-AT clone I have started to experience phantom selections when scrolling through items in the menu. This doesn't happen with k firmware or the original 1.12k Chinese firmware that came with the tester. I'm using the internal 8Mhz oscillator if that matters at all. Is this expected? I don't see a timeout that would cause this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: itkw_com on March 30, 2022, 06:34:13 am
Hello, everyone. If I want to DIY this device, but AVR MCU is expensive, can I replace it with other MCU? For example, 8051 or pic or stm8, STM32?  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 30, 2022, 09:52:02 am
Moving to 1.45m on an AY-AT clone I have started to experience phantom selections when scrolling through items in the menu. This doesn't happen with k firmware or the original 1.12k Chinese firmware that came with the tester. I'm using the internal 8Mhz oscillator if that matters at all. Is this expected? I don't see a timeout that would cause this.

No, any menu item should only run when pressing the push button. And there's no timeout for the menu. Are you accidently pushing the rotary encoder's knob while turning?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 30, 2022, 09:54:24 am
Hello, everyone. If I want to DIY this device, but AVR MCU is expensive, can I replace it with other MCU? For example, 8051 or pic or stm8, STM32?  :)

Sorry, ATmega only.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 30, 2022, 10:42:54 am
Moving to 1.45m on an AY-AT clone I have started to experience phantom selections when scrolling through items in the menu. This doesn't happen with k firmware or the original 1.12k Chinese firmware that came with the tester. I'm using the internal 8Mhz oscillator if that matters at all.
Chinese rotary encoders are of poor quality and may cause firmware instability. This was noticed by many users of AY-AT and other clones. If changing the m-firmware encoder settings in config.h
#define ENCODER_PULSES
#define ENCODER_STEPS 
does not lead to the elimination of unpleasant effects, then you should simply replace the rotary encoder with a similar one of better quality. ;)
Another important nuance is that the firmware that was compiled for an external 8MHz quartz is undesirable to use with an internal oscillator. It's my opinion.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Klockaren on March 30, 2022, 12:36:14 pm
Adrian_Arg.,I don't understand why you are going through every possible firmware for the tester?
What do you want to get out of your tester? If your clone has a hardware defect, no firmware can fix it!
Above is the link https://disk.yandex.ru/d/yW8xa5NJgUo5z to my firmware archive with m-firmware in English for GM328A - there's also a folder is called M328Kit+TFT(AY-AT). Look carefully and you'll find everything.
Thank you for the English firmware for the GM328A. It worked perfect!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 01:44:15 am
OK just care to not brick your device...

Paul

Hi Paul, well it didn't brick it but the display is upsided down with a few scrarce pixels lit up.

I traced my config_328.h file that I had used for compiling version 1.31m (that's a long time ago on the mega328_MK-328 from Electronics Studio) and I seem to remember having made changes to the display part to get it right. Wonder if you could take a look and recompile 1.45m with the changes in the config_328.h I have uploaded?

Thanks again Paul!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 06:13:44 am
well it didn't brick it but the display is upsided down with a few scrarce pixels lit up.
Show me a photo of what an upsided image looks like on your display with firmware 1.45?
The display settings in your config_328 are no different from the settings in the Paul file.
In addition, there are settings in config.h from Paul that do not match the hardware stuffing of your clone.
For example, an external voltage reference is not included
//#define HW_REF25
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 08:14:17 am
well it didn't brick it but the display is upsided down with a few scrarce pixels lit up.
Show me a photo of what an upsided image looks like on your display with firmware 1.45?
The display settings in your config_328 are no different from the settings in the Paul file.
In addition, there are settings in config.h from Paul that do not match the hardware stuffing of your clone.
For example, an external voltage reference is not included
//#define HW_REF25
Hello Indman, here are pictures of my tester - hope they are clear enough. Tks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 08:25:10 am
Your clone is called GM328(A+) on my resource and has nothing to do with the MK-328 clone except for the display controller on the ST7565. Remember that for the future.
Later I will build new test firmware 1.45m for your clone. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 08:49:54 am
I took good note of the name of my tester in your resource directory.

Thank you for compiling the 1.45m version, as I am eager to test the resistance function!

Thanks again Indman.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 09:29:23 am
rddube, check the firmware and take new photos from the display. I have included almost all possible functions in the firmware, including continuity check, but in order to use it you need to make a hardware modification of the BUZZER which is listed in the madires manual.
P.S There is a special button on the forum to express gratitude for your help "Say Thanks" ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: PKTKS on March 31, 2022, 10:32:44 am
OK just care to not brick your device...

Paul

Hi Paul, well it didn't brick it but the display is upsided down with a few scrarce pixels lit up.

I traced my config_328.h file that I had used for compiling version 1.31m (that's a long time ago on the mega328_MK-328 from Electronics Studio) and I seem to remember having made changes to the display part to get it right. Wonder if you could take a look and recompile 1.45m with the changes in the config_328.h I have uploaded?

Thanks again Paul!

my pleasure...

BUT! These changes in the header file are not meant for this particular code..

IT DOES NOT COMPILE ...
As said you probably have a different  modified version...

need to match precisely

Paul
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 10:36:25 am
rddube, check the firmware and take new photos from the display. I have included almost all possible functions in the firmware, including continuity check, but in order to use it you need to make a hardware modification of the BUZZER which is listed in the madires manual.
P.S There is a special button on the forum to express gratitude for your help "Say Thanks" ;)

Hello Indman,

It flashes ok, but now it won't turn on...I press power button and it doesn't boot up or turn on? It lights up the screen, but as soon as I let go the switch it turns off without anything appearing on the screen?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 10:53:00 am
OK just care to not brick your device...

Paul

Hi Paul, well it didn't brick it but the display is upsided down with a few scrarce pixels lit up.

I traced my config_328.h file that I had used for compiling version 1.31m (that's a long time ago on the mega328_MK-328 from Electronics Studio) and I seem to remember having made changes to the display part to get it right. Wonder if you could take a look and recompile 1.45m with the changes in the config_328.h I have uploaded?

Thanks again Paul!

my pleasure...

BUT! These changes in the header file are not meant for this particular code..

IT DOES NOT COMPILE ...
As said you probably have a different  modified version...

need to match precisely

Paul

Hi Paul, I guess age is having it's toll on my memory, but I recall using that header file for version 1.31m, but the output back then were .bin files, as shown here in a batch file I had written to upload it to the device: avrdude -c avrisp -p m328p -P COM10 -b 19200 -e -U flash:w:"Mtester207Flash.bin":a -U eeprom:w:"Mtester207Eeprom.bin":a -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0xFC:m . So frankly, I don't remember how it used to work?

But your previous version worked, but the display was upside down, and I think Indman nailed it...just need to tweak for the display. I think Indman is looking at the results from the latest compile (the device won't start) and probably recompile or suggest some fuse changes?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 10:55:40 am
Is this very strange! Did you do a crystal cleanup before updating the firmware? Try 1 more variant of the test firmware. If you get the same effect, install Paul's firmware. Will it work?

Hi Indman, ok will try this out. Not sure what a crystal cleanup is however? Is it explained somewhere?

Also, the manual you are referring to in your archive from Markus, is it possible it is only in Russian?

Many thanks again!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 11:00:54 am
Not sure what a crystal cleanup is however? Is it explained somewhere?
Also, the manual you are referring to in your archive from Markus, is it possible it is only in Russian?
Just try the new firmware and show me the results. I think I figured out the reason why my first option didn't work. You can easily find the English manual in the distribution package Madires (ReadMe file).
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 11:07:31 am
Not sure what a crystal cleanup is however? Is it explained somewhere?
Also, the manual you are referring to in your archive from Markus, is it possible it is only in Russian?
Just try the new firmware and show me the results. I think I figured out the reason why my first option didn't work. You can easily find the English manual in the distribution package Madires (ReadMe file).

Hi Indman, ok it flashed well, when I pressed the test button, screen lighted up and turned off when I let go the test button. So I repressed the test button longer let it go and immediately repressed it and the device started showing version 1.45m perfectly and the probing! I turned it off, and and to "jerk" it again to get it going..it is not smooth, like click and go, I have to "jerk" the test button to get it to start. Also, if I hold long enough or double click the test button, I don't seem to be able to access the functions menu? I can take a video if that would help? When it does start, characters are perfect on the screen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 11:09:30 am
Also, after fumbling around with it for a few times, it locks up with nothing on the screen just the screen light up and the only way out is to pull the battery.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 11:18:28 am
I reinstalled Paul's version which seems to work fine, but the characters are upside down as in the photos with random pixels? Confused ???
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 11:46:39 am
Another firmware option.Will it work?

Eureka! Works fine now, but I can't seem to access the function menu? Is there a special key sequence different than version 1.31m?

Many thanks Indman!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 11:48:25 am
Quickly press the Test button 2 times!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 11:52:03 am
Quickly press the Test button 2 times!

When I quickly press the Test button 2 times, I get a blank screen?? Lit up but blank. I have to turn it off and restart??
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 11:54:37 am
Show a video of the device's operation. On the Paul firmware are you also unable to access the menu? Can you take a good photo of the back side of the board where the parts are located?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 12:13:55 pm
Oh, I think I discovered a cold solder on the switch, will reflow and retest and report back. Sorry about that.

Be right back.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 12:25:19 pm
Oh, I think I discovered a cold solder on the switch, will reflow and retest and report back. Sorry about that.

Be right back.

Yes, exactly that, all is fine now and working perfectly. Thank you Indman and Paul for all your help!!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 12:30:44 pm
rddube,Test3 is a basic firmware with a minimal number of functions. I put it together to make sure your device is in good working order. In my opinion, Test2 firmware should also work successfully. Try installing it again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 01:52:02 pm
rddube,Test3 is a basic firmware with a minimal number of functions. I put it together to make sure your device is in good working order. In my opinion, Test2 firmware should also work successfully. Try installing it again.

Hello again,

Ok, so reinstalled Test 2 and it has become erratic again, and there is no way to access the function menu. Put back Test3 and it works flawlessly, except that the function menu doesn't include continuity testing.

So test3 works perfectly, test2 doesnt. Test2 when I press the test button, it flashes and off. I have to jiggle or constant press down let go to get the device to work??
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 02:16:49 pm
You need to determine what does not allow full-fledged firmware to work. Try another test version.Where is the PD5(9pin) port of the processor connected? How much current does the tester draw from the power supply?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 02:48:35 pm
You need to determine what does not allow full-fledged firmware to work. Try another test version.Where is the PD5(9pin) port of the processor connected? How much current does the tester draw from the power supply?

Hello Indman, bang you nailed it. Works perfectly now with this latest version.

Attached is a photo of the port (mine has 6 pins ?) I think you are referring to.

Thanks again!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 03:01:15 pm
Works perfectly now with this latest version.
Attached is a photo of the port (mine has 6 pins?) I think you are referring to.
No,this programming connector does not interest me. I asked where the 9th leg (pin) of the ATMega328 processor is connected?
This is the pin you will need to connect the buzzer to if you want to use the continuity test.
It is also very important to measure the current that the device consumes from a + 9V power source.
I also see a lot of extra flux on your board, especially on the ZIF test pins. Wash it off!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 05:46:00 pm
Ok, so test5 doesn't work, the device doesn't start??

Here are the photos of test4 and my atmega328 chip - pin 9 seems to connect into the board, so I'll probably have to solder on the pin 9 leg.

Test4 works  perfectly!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 06:12:47 pm
Ok, so test5 doesn't work, the device doesn't start??
Hm, I can't explain it! Maybe madires will find an explanation why only changing the font from 8x8_vf to 8x8alt_win1251_vf leads to a disruption in the firmware? I tested the Test5 firmware in Proteus and it works great. :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 06:20:23 pm
Ok, so test5 doesn't work, the device doesn't start??
Hm, I can't explain it! Maybe madires will find an explanation why only changing the font from 8x8_vf to 8x8alt_win1251_vf leads to a disruption in the firmware? I tested the Test5 firmware in Proteus and it works great. :-//

Could it be the size of the file, as test4 is 89K whereas test5 is 90k?? To be more precise it's 88.2k vs 89.3k ??
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on March 31, 2022, 06:42:57 pm
Let's check if this is the case. I reduced the firmware size a bit. Try Test6 ;)

No, test6 doesn't work either. I put back Test4 and it's working perfectly??
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 31, 2022, 06:48:02 pm
OK! Then we will consider the Test4 version as definitely working for the GM328A + clone and stop there. I will delete the rest of the versions so that they do not mislead users. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: wizard1 on April 01, 2022, 06:39:15 am
Moving to 1.45m on an AY-AT clone I have started to experience phantom selections when scrolling through items in the menu. This doesn't happen with k firmware or the original 1.12k Chinese firmware that came with the tester. I'm using the internal 8Mhz oscillator if that matters at all. Is this expected? I don't see a timeout that would cause this.

No, any menu item should only run when pressing the push button. And there's no timeout for the menu. Are you accidently pushing the rotary encoder's knob while turning?

I'm not accidentally pressing the knob. It's very odd that this only occurs with the m firmware. I'm searching for an alternate rotary encoder to try that. Interestingly when I have my scope hooked up to monitor the pulses from the rotary encoder everything works fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 01, 2022, 09:27:28 am
Have you tried to change the settings for ENCODER_PULSES and ENCODER_STEPS as indman suggested?
Title: Re: $20 LCR ESR Transistor checker project
Post by: wizard1 on April 02, 2022, 07:32:55 am
Have you tried to change the settings for ENCODER_PULSES and ENCODER_STEPS as indman suggested?

I tried changing those tonight. They have an impact to the rotary action but not to the switch action when I push the encoder shaft. After some more testing I believe this might be due to glitching on the switch line but I'm still not clear on why k firmware doesn't have a problem with the glitch.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 02, 2022, 10:59:55 am
OK! Then we will consider the Test4 version as definitely working for the GM328A + clone and stop there. I will delete the rest of the versions so that they do not mislead users. ;)

Hello Indman, I think will be installing winavr to get back to compiling some of this stuff. Where would I find Test4 of Markus 1.45m source code to compile and play with it?

Many thanks,

Ray
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 02, 2022, 11:44:04 am
Hi rddube!
I added the Test4 firmware along with the necessary configuration files config.h and config_328.h to the "GM328(A+)" folder on my resource https://disk.yandex.ru/d/yW8xa5NJgUo5z. Look carefully and you will find everything. I also added a Readme!!!.txt file in English to the "CloneTester" root folder, which explains how to quickly find the firmware you need from the clone photo. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 02, 2022, 01:20:17 pm
I tried changing those tonight. They have an impact to the rotary action but not to the switch action when I push the encoder shaft. After some more testing I believe this might be due to glitching on the switch line but I'm still not clear on why k firmware doesn't have a problem with the glitch.

So it's the encoder's push button which causes the issue. The k-firmware manages the rotary encoder a little bit different than the m-firmware. The m-firmware is able to monitor multiple user inputs at the same time. That's why I asked about pushing the knob accidently. Since you didn't the rotary encoder seems to have a flaky push button.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 03, 2022, 12:56:20 am
Hi rddube!
I added the Test4 firmware along with the necessary configuration files config.h and config_328.h to the "GM328(A+)" folder on my resource https://disk.yandex.ru/d/yW8xa5NJgUo5z. Look carefully and you will find everything. I also added a Readme!!!.txt file in English to the "CloneTester" root folder, which explains how to quickly find the firmware you need from the clone photo. ;)

Hello Indman...finally got my compiling environment up and running. The code in the archive for Test4 firmware compiles for me @ over 90K (hex) whereas the version you had sent me and that is already compiled in the archive is at 88.2K (hex)? Could it be that you left config.h and config328.h with the code for Test5 or Test6 ? Also, which part needs to be changed to change the font used?

Many thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 03, 2022, 01:27:13 am
Ok, so I found it in the config files - seems my compiler compiles a little larger than yours, but the code works perfectly well (Test4 version of the config.h and config328 files).

Will be experimenting now and report back if I discover anything special.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 03, 2022, 09:49:16 am
Question for programmers - I'd like to modify the ESR function of Markus version 1.45m so that it probes every X seconds, just like when you start the tester with automatic probing. How difficult would that be? Or maybe it has already been done?

Many thanks,

Ray
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 03, 2022, 10:13:39 am
Question for programmers - I'd like to modify the ESR function of Markus version 1.45m so that it probes every X seconds, just like when you start the tester with automatic probing.
Why don't you like the RCL Monitor option? That's exactly what it's designed for-automatic monitoring!
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 03, 2022, 10:23:13 am
Question for programmers - I'd like to modify the ESR function of Markus version 1.45m so that it probes every X seconds, just like when you start the tester with automatic probing.
Why don't you like the RCL Monitor option? That's exactly what it's designed for-autonatic monitoring!

Hello Indman! Ok, maybe I don't understand this, but I mean the ESR function (testing caps in circuit), whenever I want to test a cap, I have to press the test button while holding the 2 probes...I'd like it to probe automatically every 5 seconds for example. Is there a way to activate this? I know that when you start the tester you can have both modes available (automatic probing or wait for keypress) and I would like to be able to have the automatic probing in the ESR function? Tks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 03, 2022, 10:31:00 am
rddube,The in-circuit ESR measurement function of this tester has a 50% chance of obtaining a reliable result, as well as any measurement of a part in a circuit. There are many factors that affect the test result. Therefore, I exclude this function from my mod firmware. For in-circuit measurements, it is necessary to use highly specialized devices that are designed for this kind of measurement. Better yet, test parts that are dismantled from the circuit - this is the main purpose of this device.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 03, 2022, 12:36:14 pm
rddube,The in-circuit ESR measurement function of this tester has a 50% chance of obtaining a reliable result, as well as any measurement of a part in a circuit. There are many factors that affect the test result. Therefore, I exclude this function from my mod firmware. For in-circuit measurements, it is necessary to use highly specialized devices that are designed for this kind of measurement. Better yet, test parts that are dismantled from the circuit - this is the main purpose of this device.

I hear you Indman and I know it's not very accurate, but I do like to use it when I can. Certainly, if I suspect a capacitor to be bad, I'll take it out of circuit to test. Right now, I use the 1.13k version of this function because you don't have to press the test button to have it measure, albeit as inacurate as it may be. Was just wondering if I could make the 1.45m version to work in the same manner.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 03, 2022, 02:16:59 pm
Have you tried SW_MONITOR_C (in config.h)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 03, 2022, 02:57:15 pm
Have you tried SW_MONITOR_C (in config.h)?

Hello Madires,

If I enable SW_MONITOR_C it doesn't change anything. Should I disable SW_MONITOR_RCL and enable SW_MONITOR_C ?

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 03, 2022, 03:42:14 pm
Enter the main menu and run "C Monitor". ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on April 03, 2022, 05:00:34 pm
Enter the main menu and run "C Monitor". ;)

That works perfectly! Thank you Madires!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 03, 2022, 05:36:04 pm
Enter the main menu and run "C Monitor". ;)
I don't see much difference in the universal RCL Monitor mode, which also includes a separate C Monitor. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Felipe Lacerda on April 04, 2022, 10:34:03 pm
hi guys,

Attached to the (new/old) T7 images, the circuit doesn't look the same as the previous ones with a step-up transformer. :-//
firmware v3.12k? :-DD

The measurements I got:
Resistor   2.2 \$\Omega\$
DMM       2.2 \$\Omega\$
T7          1.8 \$\Omega\$  :--
(Should this compromise ESR measures, or not?)

What can I do to improve performance?
Does it support 1.45m firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2022, 05:58:49 am
Felipe Lacerda, You have a new type of T7 clone that has an ATMega328 processor and no STC power controller. Apparently the Chinese comrades have run out of ATMega324 and ATMega644 processors! ;D In any case, you first need to thoroughly rinse the board from flux residue and repeat the calibration. If this does not help, then with a high probability the firmware from GM328A (AY-AT) with minor modifications should be suitable for your clone. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 05, 2022, 07:25:07 am
hi, i have a clone of LCR TC1 with atmega644 change as published by indman, i have been using it so far it's good, but i just found a resistor measurement problem for small value measurement for example 0.22 ohm then if i measure with pin pins 1 and 3 the result the test always changes in a few seconds, for example to 0.23 0.24 0.21 0.19 my question is, is this reasonable? and can i fix this shortcoming? i have changed the stable LDO, 431 shunt, also 680 and 470k resistors with 0.1% but the test results are still not getting good results for resistance measurement..
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2022, 07:34:31 am
anwfeb,show results of hardware tests T1-T6
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 05, 2022, 08:11:39 am
Please check..
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2022, 08:17:51 am
Great results, congratulations! In what mode are you measuring resistance? Measure a 0.22 resistor between pins 1-2 and 2-3. Will there be a difference in the readings? Also try the RCL Monitor mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 05, 2022, 08:26:28 am
yes. I have changed many components to get a better value, but the measurement value < 1 ohm the results always change, for tests on legs 2 and 3 or 1 and 2 the test results also change when I press the first test start for example the 0.23 ohm result then test start next 0.21 ohms. is the problem on the pcb line that is too small? until the reading is not accurate because the small PCB path seems to have obstacles, and is the atmega644PA U-TH different from atmega644PA AU? because the component supplier in my country only has atmega644PA U-TH if this is the main problem then I have to buy imports for atmega644PA AU because I don't know for sure what is the cause of this problem..

In what mode are you measuring resistance?
I tested in auto/transistor mode on pins 1 and 3 but directly connected to Resistor and Inductor mode

for RCL Monitor i haven't tested it
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2022, 08:34:24 am
anwfeb,drift of measurement results within + - 0.05Ω is quite possible for many reasons - do not forget that this is just a tester, and not a professional meter. The drift is affected by the shortcomings of the ADC of an 8-bit processor, the heating of ports, the quality and batch of the processor, etc. d.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 05, 2022, 08:45:27 am
yes this is just a clone, and i just want to try to fix if it's possible..
testing the test button in cold conditions (when the clone hasn't been turned on at all in a few hours) the results are accurate, but when the clone has been turned on in a few minutes the test results change, even testing 0.22 ohms will get a value of 0.26 ohms that's a big difference in clone conditions has been turned on in a few minutes..
so I have to wait for the clone condition to be turned off in a few hours then the first test of the start button is usually an accurate measurement value of 0.22 ohm the results are very accurate.. different from when the clone has turned on the second and then third test even in the next few minutes the measurement value starts to change..
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2022, 08:51:08 am
What type of resistor are you using? Try to measure another highly stable type of resistance. Preferably without internal inductance, that is, non-wire.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 05, 2022, 09:05:01 am
I use this resistor, but when I try to jumper pins directly pins 1 and 3 only with solder wire the results also changed for example 0.01 - 0.03 - 0.04
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2022, 09:10:54 am
Once again, try to measure another type of precision resistor. And you can also try to solder high-quality 100nF filter capacitors directly to the power pins of the processor. Also, 431 sources in the presence of a high-quality LDO + 5V can worsen the result.

Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 05, 2022, 09:23:32 am
Once again, try to measure another type of precision resistor.
I have tried with other resistors that are more precise and the results are the same, even when I connect the jumper pin for selftest only on pins 1 and 3, the result can't be exactly 0.00 ohms, it always changes 0.01 - 0.03 - 0.04

And you can also try to solder high-quality 100nF filter capacitors directly to the power pins of the processor.
does that mean I solder directly into pins 5, 17, 27, 38 with 100nf high quality, is it enough with 1pcs 100nf on one of the vcc pins 5v to GND, or 4pcs 100nf for pins 5, 17, 27, 38 to GND
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2022, 09:25:09 am
I understand that you are currently using k-firmware? Try m-firmware and compare the results.
I solder directly into pins 5, 17, 27, 38 with 100nf high quality, is it enough with 1pcs 100nf on one of the vcc pins 5v to GND, or 4pcs 100nf for pins 5, 17, 27, 38 to GND
To check the effect, 2 capacitances between 5-6 and 17-18 pins are enough
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 05, 2022, 09:31:20 am
To check the effect, 2 capacitances between 5-6 and 17-18 pins are enough
okay i will try

do you have the latest (m) version? i already have your previous file(m) from yandex disk
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2022, 09:33:23 am
Use the working version from the Yandex disk. I have not yet collected a more recent version for this clone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 05, 2022, 09:53:01 am
okay
i have tested LCR-TC1 1.43m, test results with monitor RCL values ​​always change 0.25, 0.24, 0.22, 0.26, 0.28, 0.21, 0.29 to 0.31 i have calibrate (selftest and adjustment) and results in monitor RCL same as version(k) results are variable
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on April 05, 2022, 01:27:26 pm
So now for the table of clones we have at least 4 "T7" variants:

Attached to the (new/old) T7 images, the circuit doesn't look the same as the previous ones with a step-up transformer. :-//
firmware v3.12k? :-DD
Is there another way to differentiate this from the others aside the "v3.12k" reference?
BTW: you can look at the atmegas's date code to guess whether this is a newer or older version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2022, 01:38:09 pm
Feliciano,all the most interesting is yet to come, since the TC1 clone also has a modification based on the ATMega328 in a DIP package  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on April 05, 2022, 02:26:22 pm
i have tested LCR-TC1 1.43m, test results with monitor RCL values ​​always change 0.25, 0.24, 0.22, 0.26, 0.28, 0.21, 0.29 to 0.31 i have calibrate (selftest and adjustment) and results in monitor RCL same as version(k) results are variable
Nobody canceled the change in readings when the microprocessor warmed up. If you use the TTester for single measurements, then Selftest must be performed on a "cold" TTester. If you need to take multiple measurements, then the Selftest results should be saved after 4-5 cyclic repetitions. Saving the results of the "warmed up" TTester. Check and compare measurements after such a method.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 05, 2022, 10:19:46 pm
hi Yuriy_K
after I noticed when the clone was in "cold" conditions with "warm" conditions the difference result in measurements still continued to occur, but now I prefer selftest when the clone has been used "warm". the measurement changes are more stable than when "cold". I still use the firmware color that you made, this is specifically for my clone because i have replaced the screen with a different offset, thank you very much for your help making the firmware..

if you don't mind I want to try with the rotary encoder version, can you make a firmware for me? your firmware works fine for my clone..
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on April 05, 2022, 10:38:58 pm
Feliciano,all the most interesting is yet to come, since the TC1 clone also has a modification based on the ATMega328 in a DIP package  :-DD
:palm: The bright side is it will be easier to repair.
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 06, 2022, 10:57:42 am
Use the working version from the Yandex disk. I have not yet collected a more recent version for this clone.

Hi.. indman
did you change to the source file? i tried compiling your makefile with change source files CFLAGS += -DWITH_ROTARY_SWITCH=2 but it doesn't work for my clone TC1.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 06, 2022, 04:22:27 pm
anwfeb,yes,I explained everything in a text file ReadmeModEn.txt

Several variants of the modified m-firmware 1.45m for clone GM328A(AY-AT)! You can read all the details ReadmeModEn.txt file in the attached archive! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: anwfeb on April 06, 2022, 05:01:16 pm
yes.. i have read it and i have adjusted the encoder PIN for my clone. Thank you for the information
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 07, 2022, 01:33:07 pm
Several variants of the modified m-firmware 1.45m for clone GM328A(AY-AT)!
Sorry, I have missed a very important nuance when creating the firmware. For the correct work of the Mod1 firmware a little hardware modification of the display module and connection of Buzzer to the PD5 processor port is needed. Without these modifications the firmware will not work. So I added another basic Mod configuration in which the "Continuity" function disabled. This firmware variant, as well as the Mod2 variant, will work on your device without any hardware modifications. I've updated the archive with firmware and description!
Title: Re: $20 LCR ESR Transistor checker project
Post by: de_light on April 09, 2022, 11:30:52 pm
Probably been asked before, probably by me

What does it mean when testing a cap esr when it reads 0.00ohms?surely that can't be right.


(https://i.ibb.co/sPbqRyK/IMG-20220410-092925.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 10, 2022, 08:18:09 am
Madires already answered that question of yours here before
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3665140/#msg3665140 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3665140/#msg3665140)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 11, 2022, 05:50:28 pm
For a nice Easter weekend:
v1.46m
- Added option to disable text based pinout for 3-pin semiconductors when component symbols are enabled (UI_NO_TEXTPINOUT, suggested by bffargo@EEVblog).
- Pin designators for MOSFET's intrinsic diode, IGBT's flyback diode, BJT's flyback diode, BJT's base-emitter resistor and Schottky-clamped BJT's base-collector diode are now also color coded.
- Fixed output of symbol pinout for symmetrical JFETs (shows now 'x' for drain and source).
- Reworked management and output of pin designators for 3-pin semiconductors.
- Updated Romanian texts (thanks to Dumidan@EEVblog).
- Updated font font_8x12t_win1251_vfp.h (thanks to indman@EEVblog).
- Revised component symbols. Removed cycles and added pin designators (suggested by indman@EEVblog). Old symbols can be still used (set SYMBOLS_<size>_OLD_<format>.h in config_<MCU>.h).
- Display probe/testpin IDs with reversed colors (UI_PROBE_REVERSED, suggested by Feliciano@EEVblog).
- Added numbers 1-3 with reversed color to several fonts (thanks to Feliciano@EEVblog).
- Updated Russian texts (thanks to indman@EEVblog).
- Updated Spanisch texts (thanks to pepe10000@EEVblog).
- Updated Romanian texts (thanks to Dumidan@EEVblog).
- Updated Polish texts #2 (thanks to Jacon@EEVblog).

Please download at:
- https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
- https://github.com/kubi48/TransistorTester-source/tree/master/Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on April 12, 2022, 02:49:22 pm
Hello.

I have tried the new version, but I have noticed something strange.

If I use the English language and the default font FONT_10X16_HF that I have always used, the letters on the screen come out wrong:

(https://imgur.com/bjbMvM7.jpg)

I have tried to use the Spanish language with the same font FONT_10X16_HF and the result is similar, they cannot be read.

But, if I use the font FONT_10X16_ISO8859_2_HF, the letters come out fine, both in English:

(https://imgur.com/dHMgbnh.jpg)

Like in Spanish:

(https://imgur.com/bv8kKGe.jpg)

The problem is that this font FONT_10X16_ISO8859_2_HF takes up more space and forces me to disable some features so that the firmware does not exceed the available space.

This is normal?.

Would it be possible to go back to using the standard font FONT_10X16_HF which takes up less memory?

Thank you and greetings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2022, 03:24:24 pm
The characters are shifted by one. Let's check the font... Found it. Please edit font_10x16_hf.h and insert after the bitmap for '(':
Code: [Select]
  0x00,0x00,0x06,0x00,0x18,0x00,0x30,0x00,0x20,0x00,0x40,0x00,0x40,0x00,0x40,0x00,
  0x40,0x00,0x40,0x00,0x40,0x00,0x20,0x00,0x30,0x00,0x18,0x00,0x06,0x00,0x00,0x00,   /* 0x19 ) */

Somehow I managed to delete those two lines.  ::)

Edit: The next character  (0x1a '*') is also affected. Please replace the bitmap data with:
Code: [Select]
  0x00,0x00,0x10,0x00,0x10,0x00,0xD6,0x00,0x6C,0x00,0x28,0x00,0x38,0x00,0x28,0x00,
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,   /* 0x1a * */
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on April 12, 2022, 03:54:55 pm
Hello.

Perfect, adding these two lines the screen can be read correctly again.

Tomorrow I will recompile everything again so I can activate the features that I had to remove for it to pick up the firmware so I can get the most out of it.

Thank you very much for everything and greetings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 12, 2022, 05:15:17 pm
Madires,I updated the Russian manual in pdf format and also slightly corrected the Russian translation of var_russian.h  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on April 13, 2022, 06:47:34 am
Hello madires.

Once the two lines have been added to the FONT_10X16_HF font, the texts on the screen can now be read correctly.

I have recompiled with the options I need and the tester is working fine.

But after the first more thorough tests, I have discovered that some strange artifacts still come out, see attached photos.

I think the problem is in the lines:

Quote
  0x00,0x00,0x06,0x00,0x18,0x00,0x30,0x00,0x20,0x00,0x40,0x00,0x40,0x00,0x40,0x00,
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,   /* 0x1a * */

Which should be like this:

Quote
  0x00,0x00,0x10,0x00,0x10,0x00,0xD6,0x00,0x6C,0x00,0x28,0x00,0x38,0x00,0x28,0x00,
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,   /* 0x1a * */

All the best.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on April 13, 2022, 07:23:19 am
Probably been asked before, probably by me
What does it mean when testing a cap esr when it reads 0.00ohms?surely that can't be right.
Your readings may be the result of an incorrect Adjustment. Photo 1 shows a jumper for closing the measuring contacts, an auxiliary capacitance for tuning, and the measured polymer capacitor itself. Before Adjustment, we measure the auxiliary capacity 5-10 times photo 2-3. Then, without turning off the TTester, select Adjustment in the Menu and, upon completion of the test, save the settings in Save. When checking capacitors, the polarity of the connection must be observed, this is shown in photo 4-5 (arrows show "-").
This is especially noticeable on polymer and tantalum capacitors.
P.S. Version 1.46m works great, but I'm testing with my trusted fonts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 13, 2022, 10:13:52 am
But after the first more thorough tests, I have discovered that some strange artifacts still come out, see attached photos.

Yep, '*' (the next character after ')') is also effected. It got the top part of the ')'. I've updated the post with the changes to include also the fix for the '*'.
Title: Re: $20 LCR ESR Transistor checker project
Post by: fabriciofx on April 14, 2022, 02:42:11 pm
So guys,

sorry for this question, but what is the nowadays cheap chinese $20 LCR ESR test do buy? I saw some options, but I'm bit lost because some people said the best ar those we can update firmware, but I don't know.

I appreciate some suggestions!

Best Regards!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 15, 2022, 06:02:28 am
madires,is it possible to add the option "SW_SYMBOLS_TEST" by analogy with the option "SW_FONT_TEST"?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 15, 2022, 10:23:17 am
sorry for this question, but what is the nowadays cheap chinese $20 LCR ESR test do buy? I saw some options, but I'm bit lost because some people said the best ar those we can update firmware, but I don't know.

We had this question a few pages back. There you'll find your answers!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 15, 2022, 10:48:56 am
madires,is it possible to add the option "SW_SYMBOLS_TEST" by analogy with the option "SW_FONT_TEST"?

Yes, it's possible. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: fabriciofx on April 15, 2022, 01:01:27 pm
Hi madires!

Thanks for answer my question!

I've bought this one: https://www.aliexpress.com/item/32310123631.html?spm=a2g0o.order_list.0.0.21ef1802zWTjNT (https://www.aliexpress.com/item/32310123631.html?spm=a2g0o.order_list.0.0.21ef1802zWTjNT)

Was it a good choice?

Best Regards!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 15, 2022, 02:40:49 pm
The MK-328 is an average clone with a nice enclosure. Nothing wrong with that. If you like to improve your tester please see Karl-Heinz' excellent documentation (https://github.com/kubi48/TransistorTester-documentation/blob/main/pdftex/english/ttester.pdf).
Title: Re: $20 LCR ESR Transistor checker project
Post by: cdev on April 21, 2022, 07:17:55 pm
My AVR Transistor tester still sits on my desk despite my having bought test equipment that does what it did better. Why? It is really good at clarifying my thinking sometimes.. Thats the best way to put it.  Components sometimes look a certain way to it, and I find that insight invariably valuable. In saving time.
It does surprisingly well at measuring capacitance and inductance..
Its the best deal around, up there with the $6 logic probe.. thsts super useful also with sigrok/pulseview..
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on May 01, 2022, 07:39:52 pm
The characters are shifted by one. Let's check the font... Found it. Please edit font_10x16_hf.h and insert after the bitmap for '('
Hi madires,
I downloaded today your 1.46m, made, updated my T7, and got the same "Dpnqpofou..." bug.
Are you sure you updated your github file?
Regards,
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 01, 2022, 08:26:05 pm
I didn't update the 1.46m archive but you can use the attached file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on May 01, 2022, 10:42:58 pm
I already had updated the font bitmaps according to your directions on the previous page. Thanks anyways.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lhlad on May 13, 2022, 09:57:40 pm
Hello

I have put a config of the m firmware here https://gitlab.com/a11059/t7_328_m.git that works on my recenlty purchased T7 with atmega 328 image below.
There's also a schematic in there, it may have some errors/ommisions.

Thankyou Markus.

[attachimg=1]
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2022, 04:27:48 pm
That new variant of the T7 seems to have a pin header for the hardware serial interface. The additional 8-pin MCU could be a level shifter for 3.3V serial? The drawback is that PB2 is used for the LCD, i.e. no signal output (PWM/squarewave/...) possible. You've changed the SPI clock to a lower rate. Was there an SPI clock issue with the LCD?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 16, 2022, 02:10:07 pm
Madires,the version of the T7 clone(photo) that Felipe Lacerda offered us on page 303 of this thread is even more mysterious?! :D
It is not based on the classical ATMega328 but most likely on the Chinese analog LGT8F328P. This was reported by another owner of the same clone on a Russian-language forum.

I made several different symbols set options (24x24_vfp, 30x32_hf and 32x32_hf) for m-firmware and would like to hear your opinion - are there any bugs or reasonable suggestions for corrections to the style?
In the screenshot on the left, a set of symbols with a thin outline, and on the right side a set of symbols with a bold outline. If there are no comments or amendments, then madires will add these sets to their new release of m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lhlad on May 16, 2022, 05:33:22 pm
Yes couldn't really work out what the 15L104W is there for.  It isn't connected to anything other than the serial ports on the 328.  The only thing i've seen it do, with the original firmware, still on the original 328 but not readable, is receive some serial input from the 328 and then respond, happens every time its powered up.  The 328 send whats looks like some binary data that finishes with the ascii text "ending." the 15l104 replys with an ascii number and "OK" in ascii from memory something like "3624OK!". It didn't come with the header pins BTW I soldered them on. 

Re the spi I kept getting a blank white screen trying the hardware spi when bitbang displayed stuff.   I saw a suggestion I think you gave someone else in here to try reducing clock rate so I did quarter worked and half worked.  Possible if I go back to default it would work now because I solved another issue with my confusion over the CS and Reset pins after.  But working fine as is.
 
Oh I also changed the 5v reg, supply not really high enough for the original,  for a better LDO one and adjusted the UREF_VCC to reflect the actual when measured, not sure if should do that?  Seems reasonably accurate compared to other measure kit have access to.

Also nearly forgot to mention the IR receiver function didn't work at all with the orignal firmware, no sensible response from supplier.  I could see sensor OK with scope.  Part of the motivation for the firmware change, it works fine now.

Cheers
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: theHWcave on May 16, 2022, 11:45:07 pm
Hi Markus, I just upgraded from 1.45m to 1.46m and after applying the font fix, everything works great. Many thanks.

I use my tester (similar to MEGA_328_Colour) a lot to do in-circuit capacitance and ESR measurements and it is brilliant for that. Can you explain if the ESR menu item is different in measurement methodology from the C-monitor (which also shows ESR) ?

My reason in asking is that a lot of times I am using probes to measure on a PCB which often needs precision placement. Using 2 hands for the probes means the ESR menu is not great because it requires a button press. The C-monitor is better for me because it automatically repeats. But my problem with that method is that I need to look up to see the display which is not always possible because I may shift the probes in doing so and if that happens the readout is of course gone.

Since neither are ideal for tricky measurement conditions, I wonder what your thoughts are of a special version of the autohold similar to say Fluke and some other high-end gear.  For example, if one probes a new cap, it measures and shows the measurements on the display, but when then taking the probes off (i.e. a near zero value is detected) it freezes the display of the last previously measured good value until the probes are reapplied for another measurement. That way one can measure without having to press any buttons or needing to squint or hurry to read the display before it disappears. It would be great if that type of autohold could be enabled or disabled through the menu

Sequence could be something like this:
Event: probes in the air (=near zero measurement) --> State: Hold  (display the last value significantly greater than near zero)
Event: probes applied (=measurements significantly higher than zero) --> State: Wait  (do measuring and update values on the display)

not sure if this is too primitive to work. It is also a question of what threshold is a near-zero measurement. I know there are more fanciful algorithms where a value has to be sufficiently different (say 10%) from the previous value to get through to the display. Maybe that would work better, but then, especially in probing caps, its quite common to have a lot of close values which might not be detected as sufficiently different...

 

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 17, 2022, 08:18:03 am
But my problem with that method is that I need to look up to see the display which is not always possible because I may shift the probes in doing so and if that happens the readout is of course gone.
I do not see anything wrong with the fact that the readings will disappear for a while, which indicates that you currently have a bad connection. The C-Monitor mode was conceived and implemented precisely for this purpose, in order to monitor the change in capacitance and ESR in real time, since these parameters are unstable and can vary significantly from the influence of many factors - temperature, humidity, leakage,poor contact, etc. . It's my opinion. ;)

It would be great if that type of autohold could be enabled or disabled through the menu
In this case, you risk getting erroneous capacity status values ​​for the reasons that I mentioned above.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 17, 2022, 09:43:53 am
Yes couldn't really work out what the 15L104W is there for.  It isn't connected to anything other than the serial ports on the 328.  The only thing i've seen it do, with the original firmware, still on the original 328 but not readable, is receive some serial input from the 328 and then respond, happens every time its powered up.  The 328 send whats looks like some binary data that finishes with the ascii text "ending." the 15l104 replys with an ascii number and "OK" in ascii from memory something like "3624OK!".

Interesting! Then the 15L104W could be removed when running one of the OSHW firmwares. In other TC-1/T7 variants it's used to control power and the test button.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 17, 2022, 10:10:08 am
I use my tester (similar to MEGA_328_Colour) a lot to do in-circuit capacitance and ESR measurements and it is brilliant for that. Can you explain if the ESR menu item is different in measurement methodology from the C-monitor (which also shows ESR) ?

The measurement methodology is the same, just the user interaction is different.

Since neither are ideal for tricky measurement conditions, I wonder what your thoughts are of a special version of the autohold similar to say Fluke and some other high-end gear.  For example, if one probes a new cap, it measures and shows the measurements on the display, but when then taking the probes off (i.e. a near zero value is detected) it freezes the display of the last previously measured good value until the probes are reapplied for another measurement. That way one can measure without having to press any buttons or needing to squint or hurry to read the display before it disappears. It would be great if that type of autohold could be enabled or disabled through the menu

I could add an option to display the last valid measurement result in the third text line. Would this help?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on May 17, 2022, 10:57:57 am
a lot of times I am using probes to measure on a PCB which often needs precision placement. Using 2 hands for the probes means the ESR menu is not great because it requires a button press. The C-monitor is better for me because it automatically repeats.
For the m-firmware, you can also set the ctester to "continous mode" instead of "autohold", and/or set the timers to allow you read the measurement results before a starting a new test cycle.
Title: Re: $20 LCR ESR Transistor checker project
Post by: theHWcave on May 17, 2022, 07:32:19 pm
@madires

Yes, a "previous (stable) value" could work. I wonder if there might be an issue (software wise) to recognise the last previous value. I mean removing the probes produces more measurements, just the values are usually very small and normally no ESR is shown. So maybe the lack of ESR could be used?
Title: Re: $20 LCR ESR Transistor checker project
Post by: theHWcave on May 17, 2022, 07:57:21 pm
a lot of times I am using probes to measure on a PCB which often needs precision placement. Using 2 hands for the probes means the ESR menu is not great because it requires a button press. The C-monitor is better for me because it automatically repeats.
For the m-firmware, you can also set the ctester to "continous mode" instead of "autohold", and/or set the timers to allow you read the measurement results before a starting a new test cycle.

Thanks but I am well aware of this. The problem is that neither mode works well (for me) when using flying probes to measure ESR in circuit. I don't have a hand free to press the button (autohold) and in continuous mode, if I have to concentrate on where I probe, I can't look at the display. More often than not when trying to look at the display I lose firm probe contact ever so slightly, thus removing or changing (ESR) the displayed value just before I can read it (very frustrating...). Sometimes the soldering points and traces of old kit (most likely to have developed bad caps) are a bit tarnished and hard to probe reliably despite using needle probes & pressure.
Maybe its just me but I long to have a true Fluke-style smart autohold ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: theHWcave on May 17, 2022, 08:53:17 pm
I've stumbled over LOPT/FBT testers (also called ring tester). It should be possible to design a simple hardware option for the Transistortester to do the same, i.e a test adapter for the three probes with a counter output for T0. Would you be interested in such a ring tester option?
Another question (sorry). Is there a schematic for what the tester expects as front-end for the Ring Tester (probes) option? I looked at Bob's Basic Ring Tester and its a whole standalone tester by itself. Obviously the counting and pulse gen is done by the ATMEGA but what else from Bob's circuit is needed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 18, 2022, 10:59:29 am
Yes, a "previous (stable) value" could work. I wonder if there might be an issue (software wise) to recognise the last previous value. I mean removing the probes produces more measurements, just the values are usually very small and normally no ESR is shown. So maybe the lack of ESR could be used?

Might be an idea!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 18, 2022, 11:01:02 am
Another question (sorry). Is there a schematic for what the tester expects as front-end for the Ring Tester (probes) option? I looked at Bob's Basic Ring Tester and its a whole standalone tester by itself. Obviously the counting and pulse gen is done by the ATMEGA but what else from Bob's circuit is needed?

Please see https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/RingTester-Option.pdf.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on May 18, 2022, 12:11:04 pm
Thanks indman for developing those symbols.

I think they are easy on the eyes, specially the bold ones.
I notice they are rectangular on the picture you kinldy shared, I'm not sure if it's because the different resolution on X and Y, and/or aspect ratio of the screen or something else, so just to confirm: It will be seen somehow square when displayed on the actual screen?
On the other hand, I also notice the SCRs are narrower than the rest, therefore it's just a matter of tastes, but you could move the G a little bit to the left on those. And on the same line of thinking, you could move the B of the BJTs a little bit to the right.

Whatever you decide, it will be very welcome.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 18, 2022, 02:17:56 pm
I think I should add some background info about what's going on with the symbols. The next version will have an option to place the probe numbers in an alternative way. Currently the probe numbers are placed left and right of the symbol. The new option will move the right-hand numbers above and below the symbol (and the symbol is moved to the right). A new positioning flag can place a probe number in the mid (old: only top/bottom). This will make the fancy pinout easier to read for some folks. And we'll also have an option for a question mark symbol when no component was detected. This is accompanied by indman working on additional symbol sets.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 18, 2022, 02:50:06 pm
On the other hand, I also notice the SCRs are narrower than the rest, therefore it's just a matter of tastes, but you could move the G a little bit to the left on those. And on the same line of thinking, you could move the B of the BJTs a little bit to the right.
You have very good eyesight, congratulations on that! When you work with similar images of symbols for a long time, your eyes get tired and you can miss important details. :) That's why I decided to get your opinion on the new styles in symbols.
I will arrange the letters G and B as you noticed. As for the slightly narrow SCR symbol, this is due to the fact that the letters A and C are slightly larger in size. But I will reduce their size a little and make the symbol larger and the same as in the thin set. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on May 18, 2022, 07:10:27 pm
Indeed several set of eyes can discover more than just one.

If you are going to resize/move letters, I think your standard is 1px of separation between text and lines, but in some cases you have 2 vertical or 2 horizontal. And there is a "1" extra-bold on the bottom-left UJT.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 18, 2022, 08:11:54 pm
And there is a "1" extra-bold on the bottom-left UJT.
No, everything is fine with this  "1", it just got distorted when I made a collage of screenshots. :)
I've updated the symbol images so that the 2 different sets have the same symbol placement and letters placement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on May 19, 2022, 11:38:48 am
Hi all, first post on this forum. I have a problem with my fish8840 avr transistor tester from 2014-07, I powered it on but the lcd screen went blank. then i peered between the pcbs and realised an offcut of wire had got in and shorted stuff out. i guess there are burned pins now. would isp flashing bring it back to life?  most likely not i assume.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 19, 2022, 11:56:40 am
Welcome! First check the power supply section (should output 5V when the test button is pressed). Then connect an LED to the probes and check if it's blinking.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on May 19, 2022, 12:09:11 pm
I checked the voltage at the isp header and i get 4.97 volts. i plugged in the led at 1 and 3 on the socket and it does blink.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 19, 2022, 12:33:29 pm
In that case the LCD and/or the MCU pins driving the LCD could be damaged. Do you have a logic analyzer or scope?
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on May 19, 2022, 12:57:47 pm
I have neither, and if I did i would have no idea how to use them. iirc there was a mode where the transistor tester could report readings over a serial terminal. maybe that could be used to test the mcu, bypassing the lcd.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 19, 2022, 02:23:14 pm
Yep, serial output is an option. In case you want to replace the LCD, the monochrome LCD is a ST7565 and the color LCD a ST7735. Both are inexpensive and easy to get.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 19, 2022, 02:28:16 pm
Hi all, first post on this forum. I have a problem with my fish8840 avr transistor tester from 2014-07, I powered it on but the lcd screen went blank.
Show a picture of your display from both sides. In this clone, the display can be quickly separated from the main board.
You need to check if +5V power is supplied to the display and if the 3.3V regulator is OK
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on May 19, 2022, 02:45:15 pm
I am getting 5v on the lcd header and when i soldered a wire to the 3 pin regulator behind the lcd i got 3.293v on it so it seems to be ok. when i say the lcd is blank i mean that there is a backlight but nothing shown on screen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 19, 2022, 03:01:13 pm
From the photo I can see that your clone is in poor condition with dust, dirt and flux residue everywhere.
First you need to wash off all the dirt and inspect the boards for broken printed circuit conductors. Also, I do not exclude the possibility that there is a breakage in the cable that connects the display to the main board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on May 19, 2022, 03:30:37 pm
I think i have a 1602 lcd around here. do you know how to wire it up.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 19, 2022, 04:19:30 pm
gipetto, see
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3678982/#msg3678982 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3678982/#msg3678982)
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on May 19, 2022, 05:06:16 pm
thanks. the wiring is different. i think i'll call it quits.

On an unrelated subject i have made a mechanical keyboard with atmega328p. some related keyboards also support ssd1306 lcd for useful features like tamagotchi. I had an idea to make a keyboard that could work as an avr transistor tester, since they both use much the same hardware. would a psu usb 5v be stable for component measurements? I could use an atmega32a to free up more pins. I don't think both transistor tester and keyboard firmware could fit at the same time though, nor would i be able to handle coding. i guess a jmp instruction could select between firmwares, if both were appended in a text file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: taste_tester on May 20, 2022, 02:18:41 am
Is anyone using this alternate firmware on "Bside ESR02 Pro"?? and any mods needed besides  16mhz for this one?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 21, 2022, 02:39:44 pm
The BSIDE ESR02 Pro runs fine with k and m-firmware without any mods (it comes with the k-firmware). Of course you can improve the tester if you like.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GGMM on May 23, 2022, 05:16:51 pm
Hello,

I put this kit together. It works very well. (Menu access)
It’s powered by a 9v rechargeable battery, and I don’t understand why the P6KE6v8 component is so hot.
When I look at the diagram, it is directly connected from the VCC to the ground.
I think the VCC is the 9V, so if I’m not mistaken it may be in protection ??? It’s a 6V8 model i think!
Component that has no cabling direction, so no error.
Tell me if I’m wrong about the value of the VCC, or if there’s anything else to see.
Or don’t  look correctly the schématic?? Lol?
thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 23, 2022, 05:48:37 pm
Vcc is 5V (5V voltage regulator). There are two versions of the TVS, one is unidirectional (P6KE6V8A) and the other bidirectional (P6KE6.8CA). For the unidirectional the polarity matters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GGMM on May 23, 2022, 06:40:34 pm
Hello madires,

Thanks for your answer

On the file I downloaded, I was looking at page 20
there is no indication of VCC behind the regulator.!!
On the other hand, another diagram, page 10, where the VCC is indicated in output of the regulator.
Is this the latest version? If there’s anything better, I’ll take it.
I’m gonna check my clone’s circuit, maybe he’s got a mistake??
To see.
See in attached  the last file I downloaded. If best version, thank's to :D share.
cdt
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 23, 2022, 07:02:05 pm
You'll find the latest version of Karl-Heinz' excellent documentation at https://github.com/kubi48/TransistorTester-documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on May 23, 2022, 07:27:01 pm
GGMM:

The 6V8 inputs protection shouldn't be hot under normal conditions because the Vcc should be 5.0V after the voltage regulator, hence Vcc shouldn't be close to 0V unless something is in short-cirtuit (maybe the TVS and/or other protection) and/or the regulator is damaged.

As I'm not sure which specific kit you assembled, we can only guess.

BTW: on the k-firmware and indman folders there is a table of clones, so you can name yours.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Danyit on May 24, 2022, 04:54:24 pm
Hello, please can someone help me? I am in total confusion.
I have the M328Kit+TFT, bought here with 1.13K firmware https://it.aliexpress.com/item/32675418755.html?spm=a2g0o.order_list.0.0.21ef3696r4KtrG&gatewayAdapt=glo2ita (https://it.aliexpress.com/item/32675418755.html?spm=a2g0o.order_list.0.0.21ef3696r4KtrG&gatewayAdapt=glo2ita)

1) I read that this kind of tester must be improved for proper working, here a link https://github.com/blurpy/transistor-tester/blob/master/resources/AY-AT-J1.3.png (https://github.com/blurpy/transistor-tester/blob/master/resources/AY-AT-J1.3.png) is it true?
I will upgrade original firmware with the 1.46m version, and here I am really confused.
2) For the reprogram, Is the arduino nano a good choose, following this guide https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/ (https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/)?
3) For this firmware I have to build the firmware, or is there something ready for my hardware, where I can only change the firmware feature?
For now that's all  ;D
Please help me... Thank you...
Title: Re: $20 LCR ESR Transistor checker project
Post by: GGMM on May 24, 2022, 04:58:30 pm
Hello,

The regulator looks HS. I have 9v input and 6.8v output, not 5v. (Protective voltage will be active in continus , so warm), which is not normal.
 I’ve checked the entire circuit board, nothing abnormal.  No short circuit or other
I don’t have any small in stock. Only big
Well, I could do the test with a bigger one with a test connection.
To be see

cdt

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 24, 2022, 05:54:39 pm
1) I read that this kind of tester must be improved for proper working, here a link https://github.com/blurpy/transistor-tester/blob/master/resources/AY-AT-J1.3.png (https://github.com/blurpy/transistor-tester/blob/master/resources/AY-AT-J1.3.png) is it true?

It can be improved, but you don't have to if you're happy with your clone as it is.

2) For the reprogram, Is the arduino nano a good choose, following this guide https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/ (https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/)?

Any AVR ISP programmer is fine, e.g. an Arduino with the ISP scetch or an inexpensive USBASP clone.

3) For this firmware I have to build the firmware, or is there something ready for my hardware, where I can only change the firmware feature?

Use the settings listed in the Clones file as starting point.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 24, 2022, 05:56:08 pm
The regulator looks HS. I have 9v input and 6.8v output, not 5v. (Protective voltage will be active in continus , so warm), which is not normal.

Is the 5V regulator shot?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Danyit on May 25, 2022, 07:57:58 am
@madires Thank you...
2) Ok so I can follow the linked guide, paying attention to the arduino nano pinout. In the section # avrdude: ISP programmer, port and options in Makefile, I have to choose # Arduino as ISP, is it true?
3) Where is Clone file? Do you mean page 67 of the user manual?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 25, 2022, 09:20:40 am
2) Ok so I can follow the linked guide, paying attention to the arduino nano pinout. In the section # avrdude: ISP programmer, port and options in Makefile, I have to choose # Arduino as ISP, is it true?

Yep!

3) Where is Clone file? Do you mean page 67 of the user manual?

The Clones file is in the m-firmware's source archive (ComponentTester-1.46m.tgz). The manual you've mentioned includes a copy of the Clones file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mclute0 on May 26, 2022, 09:44:52 pm
Has anyone tried one of these round testers with the two USB ports?

https://www.aliexpress.com/item/3256803630829124.html (https://www.aliexpress.com/item/3256803630829124.html)

I think a USB power supply might be better than some of the regulators in the Chinese versions. I blew up my first one using a 12v wall wart.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 27, 2022, 11:46:40 am
IIRC, we need to add support for the 74HC164 serial shift register to the semi-ST7735 driver for that new GM328A variant. It comes with an MCU emulating an ST7735 with reversed color order (BGR instead of RGB). Any circuit diagram already available?
Title: Re: $20 LCR ESR Transistor checker project
Post by: lhlad on May 28, 2022, 01:02:19 pm
Some more background info on the symbol sizes in the m-firmware ;) At the moment there are two bitmap sets, 24x24 (horizontal & vertical bit orders) and 32x32 (horizontal only). As larger the symbols as larger the firmware. Based on the display controller you have to select a bitmap with a specific bit order. ILI9341 and ST7735 need horizontal order, and ST7565 is page-wise vertical. For ILI9341 and ST7735 you can change SYMBOL_RESIZE in the driver source file to resize the symbols by that factor. I've choosen the defaults to match the display size. For the ST7735 you can choose between SYMBOLS_24X24_H (default) and SYMBOLS_32X32_H in the config_328.h and change the sizing factor (default: 2) via SYMBOL_RESIZE in ST7735.c.

In case someone likes to draw some nicer symbols, I've written a tool to convert the bitmaps from and to different bit orders, including page-wise grouping.

Hi Madires

Is the tool you mention in the above available anywhere?

Cheers
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 28, 2022, 03:42:20 pm
Not publicly. Please send me an email.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GGMM on May 28, 2022, 03:57:59 pm
Hello Madires

I have changed the 7550 regulator by a 78L05.
It's work well now

Watch out for connections that are differenst  for these 2 regulators, but it’s functional.
cdt
Title: Re: $20 LCR ESR Transistor checker project
Post by: Danyit on May 30, 2022, 09:19:24 am
@madires I hope that I only have last request. If I want use pl-2303 usb to serial programmer, what avrdude: ISP programmer I have to choose in the makefile? And please what software did you recommend to put this 2 files into transitor checker?
Thank you very much for you help and time...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 30, 2022, 10:48:07 am
Haven't tried programming the ATmega with a PL-2303 yet. Maybe this helps: http://nerdralph.blogspot.com/2014/05/pl-2303hx-bit-bang-avr-programmer.html. (http://nerdralph.blogspot.com/2014/05/pl-2303hx-bit-bang-avr-programmer.html.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on June 05, 2022, 01:04:27 pm
Hello Madires.
How do you feel about this idea. Add a vertical diode symbol to the font and display this symbol as shown in the photo. It would be easier if all component symbols were displayed in a fixed location (no vertical shifts). I've just started to redo it, it takes more time. Do not pay attention to my colors, I did it for myself.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 05, 2022, 03:48:11 pm
That's a nice idea! Since indman is working on alternative symbol sets I'd suggest to wait until he has finished the symbol sets (some already include the MOSFET's body diode) before implementing your idea.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 05, 2022, 06:05:48 pm
Displaying the parasite diode(body) symbol as an additional diode is already used in k-firmware. But since a MOSFET include has such a diode in its structure, it is reasonable to represent it initially in the symbol. This is what the picture will look like with the alternative symbols set and the location alternative of the numeric contact numbers. This will make it much easier to read the display information. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on June 06, 2022, 02:50:08 am
That's a nice idea!
This is not an idea, but a variant of incomplete implementation. The photo shows from my display. Only arrows from Photoshop, corrected all the required places. Now everything turned out as planned to the best of my abilities.

With great changes, I managed to get the second option. In my opinion, it is more acceptable.
Title: Re: $20 LCR ESR Transistor checker project
Post by: b0hoon on June 07, 2022, 10:15:25 pm
Hi.

I attach corrected fonts from firmware 1.46m:

font_6x8_iso8859-2_hf -> lack of cathode line in the first diode symbol, fixed badly encoded "W" letter (0x44 -> 0x14)
font_8x8_iso8859-2_h -> fixed index of "\" in index table (0x4b -> 0x4c)
font_10x16_hf -> lack of data for ")" symbol (it's 0x19), fonts are useless without it, cause it shifts the data in relation to index table

Additionally i attach fonts converted with my tool from font_8x12t_iso8859-2_vfp and font_8x16_iso8859-2_vfp to hf format, which are for me very usefull for GM328(A) testers.


Title: Re: $20 LCR ESR Transistor checker project
Post by: ifonlyeverything on June 10, 2022, 02:39:45 am
Before I potentially waste money, can logic analyzer style probes be used on this meter without messing up accuracy too badly? Something like https://www.ebay.com/itm/374089380526 (https://www.ebay.com/itm/374089380526) I want to be able to use test inductors and oddly shaped capacitors without twisting and contorting the leads.

edit: This may be helpful for anyone else in a similar position. https://sigrok.org/wiki/Probe_comparison (https://sigrok.org/wiki/Probe_comparison)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 10, 2022, 10:00:48 am
Yes! But the cheap Chinese ones usually have a poor contact and the wires break off easily.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on June 11, 2022, 07:32:48 am
As you are on the topic of graphics here I'll ask:
In the M-firmware the acronym Ube is used for transistors Vbe voltage.
It is a German acronym, anyone knows if it is by design or an oversight?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 11, 2022, 07:45:15 am
Your photo shows k-firmware. The m-firmware uses the designation Vbe. There is nothing stopping you from changing the parameter designation in k-firmware to one that suits you best. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on June 11, 2022, 07:52:29 am
Yes sorry that was a typo, I'm aware I'm using the k-firmware, and hence the logic use of the acronym Ube since it is written by Karl-Heinz Kübbeler in Germany :)
I was just curious if others noticed this and thought it was an oversight or not... :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 11, 2022, 09:34:32 am
Easy to change in Transistortester.h:
Code: [Select]
const unsigned char Ube_str[] MEM_TEXT = "Ube=";
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on June 12, 2022, 11:12:40 am
Finally someone explains an upgrade to 1.46 I can digest!  :-+  Enjoy  :popcorn:
https://www.youtube.com/watch?v=P5zWMnvjfM4 (https://www.youtube.com/watch?v=P5zWMnvjfM4)
* Post edit *
Famous YouTuber DanyK.cz added his overview, so I might as well add it here (hard believing he's never owned one till now..) https://www.youtube.com/watch?v=B4YM_ljELl4 (https://www.youtube.com/watch?v=B4YM_ljELl4)
It's actually rather humorous watching him try 3 components simultaneously to see the results..  :-DD 
I suspect he was "playing dumb" but managing to demonstrate theory and measurement limits, it worked out well.
https://www.youtube.com/watch?v=-pEmM0Kt2UY (https://www.youtube.com/watch?v=-pEmM0Kt2UY)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 13, 2022, 06:57:14 pm
Famous YouTuber DanyK.cz added his overview, so I might as well add it here (hard believing he's never owned one till now..)
Everything that is shown in this video, you can easy find in the documentation of Karl-Heinz in detail with diagrams,tables and test results, a long time ago! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: b0hoon on June 20, 2022, 09:54:47 pm
Hi.

More fixes for fonts. Sides of resistors were swapped in file font_8x12t_iso8859-2_vfp, so in my converted hf version too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on June 24, 2022, 12:40:11 pm
I've been using Karl-Heinz firmware on my tester (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=240350).
But today I felt I should try Markus firmware on it, however I can't get the encoder to behave properly.
I have tried setting "ENCODER_PULSES" to 1,2 & 4 but it moves erratically.
If I am very careful moving one indentation while in PWM mode it will count 2 steps no matter what I set "ENCODER_PULSES" to.
That is to say one indentation seems to correspond to two pulses.
If I however turn it at a "normal slow" speed it will go very fast, probably due to the double signals?
My encoder has 24 physical indentations or steps which I've set in "ENCODER_STEPS"
What can I do to troubleshoot this further, any more info I can provide?
Out of curiosity I bought a new Bourns PEC11R-4215F-S0024 encoder, the securing legs where a little bit too wide but I snipped them down and then it fits well.
I have attached a couple screenshots, first the original Chinese encoder that was included with the kit for my unit.
Then I tried adding 100pF 0603 SMD NP0 capacitors between the legs of the A/B signals and ground to it as this is recommended in the datasheet of the Bourns encoder.
Then I changed to the Bourns encoder but I did not add the capacitors to it.
You can see that the Chinese one is just crazy: some of the indentation steps are not 90 degrees apart but more like 0 degrees or even maybe negative!
So no wonder it did not work well, I had kept the firmware I compiled back when I made the above post and it now behaves perfectly with this new encoder!
Madires: would you like that I send you this encoder? Because I have used it with Karl-Heinz firmware all this time with very little issues...
If not it will go in the trash because that is where my oscilloscope says it belongs! :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 24, 2022, 02:23:47 pm
The screenshots of the dodgy rotary encoder are interesting. Back then I bought a bunch of the cheapest encoders I could find on aliexpress to optimize the algorithm for reading the rotary encoder. They cause some glitches, but yours is truly worse. ;D There's a huge difference beween good struff from ALPS or Bourns and Chinese cheapies. I agree, your encoder should go into the e-junk container. It wouldn't help to improve the encoder algorithm, as it detects glitches and drops them, i.e. nothing happens (intended design).
Title: Re: $20 LCR ESR Transistor checker project
Post by: rsjsouza on June 24, 2022, 05:40:45 pm
This is an interesting capture of the encoder; my tester is quite erratic and I will see if an old spare that I bought for my oscilloscope will fit and work. :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 24, 2022, 05:58:46 pm
Moving to 1.45m on an AY-AT clone I have started to experience phantom selections when scrolling through items in the menu. This doesn't happen with k firmware or the original 1.12k Chinese firmware that came with the tester. I'm using the internal 8Mhz oscillator if that matters at all.
Chinese rotary encoders are of poor quality and may cause firmware instability. This was noticed by many users of AY-AT and other clones. If changing the m-firmware encoder settings in config.h
#define ENCODER_PULSES
#define ENCODER_STEPS 
does not lead to the elimination of unpleasant effects, then you should simply replace the rotary encoder with a similar one of better quality. ;)

I mentioned the poor quality of Chinese encoders several times before! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on June 28, 2022, 09:59:18 am
Hello everyone.
I am expanding the GM328 with the different Madires mounts.

E built the optocoupler tester which works perfectly.
Today and tried to mount the "sound emitter", as the schematic and as you can see in the photo, using a buzzer, a 2N2222 and a 1K5ohm resistor.
The base of the transistor connected through the resistor that is connected to PD5 (pin 11 of the Atmega), because when you connect the power supply of the GM328 and put it to work, the buzzer is always sounding.
I've checked everything, I've even reloaded the firmware again, and everything is still the same. What could be the problem?

(https://i.ibb.co/YWDDS1F/20220628-112235.jpg) (https://ibb.co/YWDDS1F)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 28, 2022, 10:25:01 am
carrascoso
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4105798/#msg4105798 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4105798/#msg4105798)
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on June 28, 2022, 10:58:06 am
carrascoso
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4105798/#msg4105798 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4105798/#msg4105798)

Thank you Indman for your quick response.
I have modified what you have told me and everything remains the same, it is constantly ringing

(https://i.ibb.co/r4YdZFS/20220628-124502-copia.jpg) (https://ibb.co/r4YdZFS)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 28, 2022, 11:20:38 am
In the config_328.h file, you must additionally disable the PD5 port for the ST7735 display
//#define LCD_CS           PD5            /* port pin used for /CSX (optional) */
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on June 28, 2022, 06:15:36 pm
Indman, I followed your instructions and all the same, constantly ringing.
I've cut the track and jumpered, and disabled //#define LCD_CS PD5, I'm using version 1.46.

Any more suggestion.
Thank you very much, greetings
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 28, 2022, 06:42:01 pm
You can program my Mod1 1.45m from the link I gave earlier and test the Buzzer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on June 29, 2022, 03:43:18 pm
indman with your firm Mod1, perfect.
I'm going to compare my config_328.h with yours to see if I find the problem.

I liked some details of your firm, such as the battery issue, the display of messages, etc.
If you don't mind, you can send me a complete signature to copy your ideas.   :-DD :-DD

Thank you very much for everything and greetings.

PD: Solved the continuity problem, it already works, my mistake   |O |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on June 30, 2022, 11:34:12 am
Indman, I told you if you could send me the files to modify some things that I like about your firm, among them:

1 - That the messages appear in the center of the screen and not at the top.
2 - The battery indicator is very good and I would like to change it because it gives it a very professional touch.
3 - Between the changes I would like to change the color of the menu (white better green, the same as the font (thicker), both changes are better seen with a lot of lighting

If you don't mind, can you tell me what would be the things to modify or files I should look at to get it.

Thank you and regards

(https://i.ibb.co/1X968zG/1-45-Mod1-En.jpg) (https://ibb.co/NNLSZT2)

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 30, 2022, 11:51:15 am
carrascoso,sorry,my firmware modification involves significant changes to the madires code in a very large number of files.
You probably missed or misunderstood what I wrote in the ReadmeModEn file:
I do not publish or distribute the mod source files!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 30, 2022, 01:47:08 pm
You can change some colors in colors.h (scroll down to the end).
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on June 30, 2022, 06:49:31 pm
You can change some colors in colors.h (scroll down to the end).

Thanks, Madires.
I already make what changes I can in colors.h, but I like the font for my view that Indman uses.
I also liked the different messages, warnings, etc. in the center of the screen, this can be done in your firm or at least I haven't found it.
And the battery icon and result is also very good, although this surely takes up a lot of memory.

Cheers
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on June 30, 2022, 09:20:59 pm
I like the font for my view that Indman uses.
You can create/modify fonts (I've shared here some improvements to existing fonts/symbols, with some cues on how I did it). For the m-firmware, there are several fonts to choose from. Think on those as bitmaps; if you understand the encoding, you can modify or create one "by hand". Or you can use one of the few AVR font tools available on the net.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 01, 2022, 02:34:34 pm
The character bitmaps aren't specific to AVRs, any font tool will do. Be aware that based on the display controller a particular bit order is needed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 01, 2022, 02:37:53 pm
I also liked the different messages, warnings, etc. in the center of the screen, this can be done in your firm or at least I haven't found it.
And the battery icon and result is also very good, although this surely takes up a lot of memory.

Maybe I'll add such features as options in the future. The next firmware version will come with several new UI options.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 02, 2022, 05:47:18 am
Maybe I'll add such features as options in the future. The next firmware version will come with several new UI options.
On the previous page, I gave an example of characters from my font. Here is an example of these images on the display...

I'll add from another thread. To obtain high accuracy when measuring small inductances on k firmware. I'm applying a little tweak, highlighted in red on the schematic fragment. On the 1st picture, the measurement of this inductance with the values indicated on the diagram. The range of possible deviation of the inductance L1 is shown in pictures 2.3.

The readings are different, different measurement methods, different frequencies. MS5308 shows within its error at this frequency. But I determined a long time ago that his readings were underestimated. After purchasing the NJ100S, I checked its readings on the standards available to me, its readings on the fuel are more accurate. Below are the readings without L1 and with L1, and error table  MS5308.

P.S. The quality factor readings differ from those previously given, it took time to normalize the parameters of the parts after soldering.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 02, 2022, 12:10:40 pm
To obtain high accuracy when measuring small inductances on k firmware. I'm applying a little tweak, highlighted in red on the schematic fragment. On the 1st picture, the measurement of this inductance with the values indicated on the diagram. The range of possible deviation of the inductance L1 is shown in pictures 2.3.
I don't see any high accuracy in measuring the inductance of R36,if you look at the readings of your 3 instruments? They are different and I can't see comparing readings without tweaking upgrade the circuitry.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Embehu on July 07, 2022, 10:21:10 pm
Hello everyone, I tried to complie the newest version of m-firmware, I got everything under (100%). However,when I uploaded the firmware, there is nothing displayed in the screen.
I’m using ay at transitor tester with some modification, the Vref of mine is 2.234V, the resistor I’m using 680R 470K with 0.1%
I also write fuses as this
fuses_lo = 0xf7
fuses_hi = 0xd9
fuses_ext = 0xfc
lock_byte = 0xff

 please guide me out of this problem. Many thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: theHWcave on July 08, 2022, 09:15:50 am
Likely either the wrong display is selected in the config_328h or the pinout to drive it is not standard. I think you need LCD_ST7735 to be active. But then, my hardware version used totally different pins to drive the LCD which I had to discover and redefine. In the hope yours may be similar, you can try my config_328h which you can download from here: https://github.com/TheHWcave/TransistorTester (https://github.com/TheHWcave/TransistorTester)  My changes are marked with "theHWcave" in the file
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 08, 2022, 10:22:16 am
Some AY-AT/GM328A come with a different LCD emulating an ST7735 (semi-compatible). That LCD module has an MCU and a level shifter on the PCB. In this case use LCD_SEMI_ST7735 (see 'Clones' file).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Embehu on July 08, 2022, 11:37:23 am
Some AY-AT/GM328A come with a different LCD emulating an ST7735 (semi-compatible). That LCD module has an MCU and a level shifter on the PCB. In this case use LCD_SEMI_ST7735 (see 'Clones' file).

Thank you so much, I flashed the new firmware, it runs into the Probing.... and then restart again and again. And the screen direction is flipping, X become Y. So what am I still doing wrong?
here is my 7735 semi that I found somewhere on internet
Code: [Select]

#define LCD_SEMI_ST7735
#define LCD_GRAPHIC                     /* graphic display */
#define LCD_COLOR                       /* color display */
#define LCD_SPI                         /* SPI interface */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RES          PD0            /* port pin used for /RESX */
#define LCD_CS           PD5            /* port pin used for /CSX (optional) */
#define LCD_DC           PD1            /* port pin used for D/CX */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SDA          PD3            /* port pin used for SDA */
#define LCD_DOTS_X       160            /* number of horizontal dots */
#define LCD_DOTS_Y       128            /* number of vertical dots */
#define LCD_LATE_ON                     /* turn on LCD after clearing it */
#define FONT_8X8_HF                     /* 8x8 font */
#define SYMBOLS_30X32_HF                /* 30x32 symbols */
#define SPI_BITBANG                     /* bit-bang SPI */
#define SPI_PORT         LCD_PORT       /* SPI port data register */
#define SPI_DDR          LCD_DDR        /* SPI port data direction register */
#define SPI_SCK          LCD_SCL        /* port pin used for SCK */
#define SPI_MOSI         LCD_SDA        /* port pin used for MOSI */

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 08, 2022, 01:40:45 pm
Does the probing cycle start again or does the tester restart (showing the firmware version)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Embehu on July 08, 2022, 02:10:27 pm
Does the probing cycle start again or does the tester restart (showing the firmware version)?

It restarts. Showing firmware version 1.46 then Battery ok, Probing... and the screen light up then get dark and start showing firmware again...
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 08, 2022, 02:19:58 pm
Embehu,Try this firmware to test the performance of your clone. ignore the russian language.
Will there be the same reboot effect as on your 1.46m?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Embehu on July 08, 2022, 02:59:13 pm
Embehu,Try this firmware to test the performance of your clone. ignore the russian language.
Will there be the same reboot effect as on your 1.46m?

Oh my God, suprisingly it works, screen also ok. But the results is not good (I think because I'm using 2,234V as Vref). 
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 08, 2022, 03:02:51 pm
Embehu,for what purpose did you apply such a Vref? Put a good quality LDO +5v and remove the external REF altogether!
Attach the zip archive to a message with your config.h and config_328.h. I will compile the 1.46m firmware for you in English.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Embehu on July 08, 2022, 03:33:02 pm
Embehu,for what purpose did you apply such a Vref? Put a good quality LDO +5v and remove the external REF altogether!
Attach the zip archive to a message with your config.h and config_328.h. I will compile the 1.46m firmware for you in English.

I got LM399 (it has 6.75 super stable Vout) from scratch then I use three 470K resistors 0.1% in series then I got 2234V. I think it will be better than mpc1720 or tl431
You are so kind to me but if I can I would love to make it myself because if I change the function I don’t really want to bother you again. Otherwise  I will send you via inbox.
Really thank you for helping me!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 08, 2022, 03:43:24 pm
I got LM399 (it has 6.75 super stable Vout) from scratch then I use three 470K resistors 0.1% in series then I got 2234V. I think it will be better than mpc1720 or tl431
Put original MCP1702-5002 - it will be enough for this clone and you will get great results without using ExtVref. LM399 can be used in other project, where high stability of the reference voltage is required. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 08, 2022, 06:07:06 pm
Yep, LM399 is total overkill.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Embehu on July 08, 2022, 09:25:52 pm
Put original MCP1702-5002 - it will be enough for this clone and you will get great results without using ExtVref. LM399 can be used in other project, where high stability of the reference voltage is required. :D

Yep, LM399 is total overkill.

Ah ha, I got it. So this project requires stability of 5V more than Vref.
Since I really get difficulty while buying the real mcp1702. How about the one from China? Do you have any idea about it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 09, 2022, 07:58:25 am
Since I really get difficulty while buying the real mcp1702. How about the one from China? Do you have any idea about it?
In 99% of cases you will receive a fake or relabeled part from China. You can take a risk and order it from a seller who has the highest number of orders of this LDO and positive feedback from buyers - shop FU NENG Store
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjt9a2qqev4AhVJKewKHYq1AFM4ChAWegQICRAB&url=https%3A%2F%2Fwww.aliexpress.com%2Fw%2Fwholesale-mcp1702.html&usg=AOvVaw0n34iQzC8z5oOlhG0OeJ6J (https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjt9a2qqev4AhVJKewKHYq1AFM4ChAWegQICRAB&url=https%3A%2F%2Fwww.aliexpress.com%2Fw%2Fwholesale-mcp1702.html&usg=AOvVaw0n34iQzC8z5oOlhG0OeJ6J)
But I'm not at all sure it'll be an original part. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Embehu on July 09, 2022, 10:58:53 am
In 99% of cases you will receive a fake or relabeled part from China. You can take a risk and order it from a seller who has the highest number of orders of this LDO and positive feedback from buyers - shop FU NENG Store
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjt9a2qqev4AhVJKewKHYq1AFM4ChAWegQICRAB&url=https%3A%2F%2Fwww.aliexpress.com%2Fw%2Fwholesale-mcp1702.html&usg=AOvVaw0n34iQzC8z5oOlhG0OeJ6J (https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjt9a2qqev4AhVJKewKHYq1AFM4ChAWegQICRAB&url=https%3A%2F%2Fwww.aliexpress.com%2Fw%2Fwholesale-mcp1702.html&usg=AOvVaw0n34iQzC8z5oOlhG0OeJ6J)
But I'm not at all sure it'll be an original part. ;)

Absolutely I know it then I would rely on the Vref function with lm399. In Vietnam it’s super hard to order just a mcp1702 from digikey or mouser because the price would be really high. Anw I will figure it out!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on July 09, 2022, 12:50:42 pm
Put original MCP1702-5002 - it will be enough for this clone and you will get great results without using ExtVref. LM399 can be used in other project, where high stability of the reference voltage is required. :D
Yep, LM399 is total overkill.
Ah ha, I got it. So this project requires stability of 5V more than Vref.
Since I really get difficulty while buying the real mcp1702. [...]
AFAIK the ATmega generates its internal Vref from an amplified bandgap (obviously feeded from Vcc), therefore if the Vcc is stable enough, so is the Internal Vref. Else, we use the external Vref.
I got LM399 (it has 6.75 super stable Vout) from scratch then I use three 470K resistors 0.1% in series then I got 2234V. I think it will be better than mpc1720 or tl431
You can either modify the source code to work with a non-standard External Vref, or you can create an arrange to obtain the one we normally use. Several examples of such arrangements can be found on the Appendix C of the AN42 of LT (https://www.analog.com/media/en/technical-documentation/application-notes/an42.pdf).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 09, 2022, 12:57:25 pm
In Vietnam it’s super hard to order just a mcp1702 from digikey or mouser because the price would be really high. Anw I will figure it out!

You can also use any other 5V regulator with a stable output (measure the voltage and update UREF_VCC in config.h).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 09, 2022, 01:11:51 pm
AFAIK the ATmega generates its internal Vref from an amplified bandgap (obviously feeded from Vcc), therefore if the Vcc is stable enough, so is the Internal Vref. Else, we use the external Vref.

The internal bandgap reference (1.1V) can vary between 1.0 and 1.2V. The Transistortester:
- assumes Vcc is 5V exactly
- can check for an external 2.5V reference and use it to update the actual Vcc
- measures the internal bandgap reference with Vcc as reference
Title: Re: $20 LCR ESR Transistor checker project
Post by: Embehu on July 09, 2022, 02:35:08 pm
My thinking is quite simple, the tester uses 2.5V as ref so I change to 2.234 then the mcu will use “new value” to calculate everything. So I’m wrong right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 09, 2022, 05:32:41 pm
In that case you'll also need to change the voltage range check in CheckVoltageRefs() in main.c:
Code: [Select]
  /* check for valid voltage range */
  if ((U_Ref > 2250) && (U_Ref < 2750))      /* voltage is fine */

Try 2000 for the lower threshold and 2500 for the upper.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lusant on July 10, 2022, 12:29:33 pm
Hi,

I know there are a lot of different models, anyway have you saw this one ?
What is the purpose of USB interface ?

I try to use it to supply the module, it shows around 7 V, but didn't measure a simple resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: LinuxHata on July 10, 2022, 01:02:30 pm
Is there a version of firmware for these devices, which skips battery tests and other welcome messages on each button press?
This is very annoying.....
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 10, 2022, 01:50:02 pm
Hi,

I know there are a lot of different models, anyway have you saw this one ?
What is the purpose of USB interface ?

I try to use it to supply the module, it shows around 7 V, but didn't measure a simple resistor.
I have no idea what version that is, but trying a OCR translation it seems to be saying that the USB port is only for user upgrades (of the firmware) and that it does not supply power.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 10, 2022, 01:59:53 pm
I know there are a lot of different models, anyway have you saw this one ?
What is the purpose of USB interface ?

No, but it looks similar to the LCR-T4, just with an additional USB to serial adapter (CH340). So the USB interface could be for TTL serial (both OSHW firmwares support a serial interface) or for ISP (programming the ATmega).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 10, 2022, 02:07:39 pm
I have no idea what version that is, but trying a OCR translation it seems to be saying that the USB port is only for user upgrades (of the firmware) and that it does not supply power.

Then it should be possible to update the firmware directly via avrdude.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 10, 2022, 02:22:27 pm
Is there a version of firmware for these devices, which skips battery tests and other welcome messages on each button press?
This is very annoying.....

Let me guess, you're still running the modified firmware which came with the clone? Which clone do you have?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 10, 2022, 03:53:45 pm
I know there are a lot of different models, anyway have you saw this one ?
A very strange implementation of the circuitry on this clone. The quartz resonator is not used, but the 7th and 8th pins of the processor are connected to an empty 6-pin connector. Instead of ExtVref, LM358 is included. Another K2 button appeared on the board ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: LinuxHata on July 10, 2022, 07:22:31 pm
I have two different models, one with B/W 1602 LCD screen (the model with red pcb and space for 9V battery), and another one with color graphical LCD. (GM-328)
Haven't touched firmware at all, but both work in the same way - a press of the button goes each time thru the initialization sequence, which is very boring :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 10, 2022, 08:15:14 pm
There's the k-firmware (https://github.com/kubi48/TransistorTester-source) and the m-firmware (https://github.com/madires/Transistortester-Warehouse). Maybe the m-firmware would be the better choice for you since it offers several options to customize the UI. Try the slightly older version 1.45m (1.46m has a small font issue impacting the GM-328A).
Title: Re: $20 LCR ESR Transistor checker project
Post by: LinuxHata on July 10, 2022, 09:14:35 pm
Thanks, and is there a brighter and bigger display option for that color one?
I've set custom colors to white, but it is still quite dim.
In fact, I need to know display controller and pinout, and I'll handle other things by myself.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 10, 2022, 10:03:21 pm
I have no idea what version that is, but trying a OCR translation it seems to be saying that the USB port is only for user upgrades (of the firmware) and that it does not supply power.

Then it should be possible to update the firmware directly via avrdude.
Just noticed there is an unpopulated 0Ω resistor R12 near the USB port.
This would power the device directly with the VCC from the serial port, not through any regulator it seems.
I wonder how well the LMV358 (U5) works as a voltage reference in this implementation.
It would be interesting to see a schematic of this unit, have you tried asking the seller @lusant?
Sometimes they have been strangely forthcoming with that...
Title: Re: $20 LCR ESR Transistor checker project
Post by: lusant on July 11, 2022, 01:16:51 am

Just noticed there is an unpopulated 0Ω resistor R12 near the USB port.
This would power the device directly with the VCC from the serial port, not through any regulator it seems.
I wonder how well the LMV358 (U5) works as a voltage reference in this implementation.
It would be interesting to see a schematic of this unit, have you tried asking the seller @lusant?
Sometimes they have been strangely forthcoming with that...

Yes, there are 3 missing resistors, that one of 0 Ohm, and more two R15 and R16 of 5.1k, these are for terminating the data lines of USB, I suppose.
The funny thing is, when supplied from USBC plug (with the mobile charger) and without battery, the display shows the message MTester and also the voltage level, 7. something Volt (it is in the box, which does not allow access to the plug, and I need to open it to connect and the be more precise).
So, anyhow the cpu is running, maybe waiting for k2 pressing and some bytes of data from USBC.

If you guys need, I can make some measures to clarify some connections.
This is my first LCR of this kind and I was surprised when I saw the USB stuff.

I don't have any schematic and I doubt the seller will send it, I can try, but ...
I bought this module two weeks ago from Aliexpress in one seller named FNIRSI Factory Store. It cost me 13.98 € with the box and the test wires and now it cost 17.06 €. The pictures in the advertising doesn't show the bottom of the PCB.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 11, 2022, 08:56:48 am
Thanks, and is there a brighter and bigger display option for that color one?
I've set custom colors to white, but it is still quite dim.
In fact, I need to know display controller and pinout, and I'll handle other things by myself.

The LCD controller and the pinout for the GM-328A is noted in the 'Clones' file. You can replace the display with a larger one if you like, e.g. ILI9341/ILI9342. Or try to change the resistor for the LED backlight.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 12, 2022, 12:55:02 pm
Thanks, and is there a brighter and bigger display option for that color one?
If desired, can be converted to displays ILI9341 2.8"
Title: Re: $20 LCR ESR Transistor checker project
Post by: LinuxHata on July 12, 2022, 09:14:11 pm
Thanks, will check it tomorrow.
And another question, my another one, with 1602 LCD, often makes same error - capacitance is displayed as 86.XX something, and ESR as 0.14K (always these values).
I've re-checked wiring, even replaced IC socket, but that does not helps. Any ideas, what can be causing this ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 13, 2022, 02:40:51 am
... Any ideas, what can be causing this ?
It is necessary to look at the readings of self-tests, whether there was a replacement of the crystal, and it is possible to change the LDO, adjust the blocking capacitances ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 13, 2022, 10:06:16 am
And another question, my another one, with 1602 LCD, often makes same error - capacitance is displayed as 86.XX something, and ESR as 0.14K (always these values).
I've re-checked wiring, even replaced IC socket, but that does not helps. Any ideas, what can be causing this ?

Powered by SMPSU, unstable voltage regulator or self-adjustment not done?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 16, 2022, 02:03:28 pm
Can someone that has compiled Madires M-firmware for the Hiland644 post the config files here so I have something to start from?
I looked through the thread but could not find anyone that had posted a working config before?
Pictures of my meter: 1 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=778521;image), 2 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=801300;image).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 16, 2022, 02:28:35 pm
The required settings for the Hiland M644 are listed in the 'Clones' file (part of the firmware archive).

BTW, the new GM328A model with the black round PCB runs fine with the Semi-ST7735 driver.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 16, 2022, 04:58:41 pm
Can someone that has compiled Madires M-firmware for the Hiland644 post the config files here so I have something to start from?
Verified changes for Hiland.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 16, 2022, 07:11:34 pm
BTW, the new GM328A model with the black round PCB runs fine with the Semi-ST7735 driver.
Yeah, it's true. For this "GM328A(BGR)2" clone I added actual k-firmware 1.13k and m-firmware 1.46m in English for 8Mhz to my firmware collection  https://yadi.sk/d/yW8xa5NJgUo5z
Also added a schematic diagram for this clone (thanks to the member of the forum 4pa.to vad.leo for creating it).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 16, 2022, 09:59:55 pm
The required settings for the Hiland M644 are listed in the 'Clones' file (part of the firmware archive).
Thank you!
Maybe something to change: in the 1.46m archive the "ILI9342" LCD is enabled with:
//#if 0 in config_644.h this took a while before I realized because Notepad++ did not do proper syntax highliting.
It was not until I viewed the file with VIM that I realized why I only had a white screen on my tester after loading the firmware on it...
The reason I think this is a mistake is that further down is this code, but it will obviously never be invoked to help the user as it is now.
Maybe it could even be improved to check if multiple displays are enabled, unless there is some use case for that?
(P.S: Not relevant for my compile but in config_328.h "ST7565R" is enabled by default instead).
Code: [Select]
/*
 *  check if a LCD module is specified
 */

#if !defined(LCD_TEXT) && !defined(LCD_GRAPHIC)
  #error <<< No LCD module specified! >>>
#endif
Lastly I think the "Clones" file should mention that you should change the MCU type in the Makefile from the default atmega328 for those models where that is relevant.

Everything should be 0xFF. Write the desired values: L = 0xFF, H = 0xD9, E = 0xFC, LB remains 0xFF.

The recommended setting of the low fuse for the Hiland M644 (ATmega 644, 8MHz) is 0xf7.
I know this is an old message but I have to ask why? Does this disable the external 8Mhz crystal and use the internal RC crystal, if so what is the purpose of this change, and if I misunderstood it can you please explain?

Verified changes for Hiland.
Thank you! I had already done pretty much exactly the same changes as you when I saw your message, but I did borrow some of them now! :)
But a question for you: does your tester not require the hFe fix? Mine does, it displayed way too high values otherwise, after enabling the fix it shows the same as my other tester:
#define NO_HFE_C_RL
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 17, 2022, 12:26:55 am
But a question for you: does your tester not require the hFe fix?
#define NO_HFE_C_RL
My previous post shows a photo of my Hiland board. You can see some changes, but there are also not noticeable ones, these are C4, C3, C10 values. I don't need to enable this option.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 17, 2022, 09:14:56 am
But a question for you: does your tester not require the hFe fix?
#define NO_HFE_C_RL
My previous post shows a photo of my Hiland board. You can see some changes, but there are also not noticeable ones, these are C4, C3, C10 values. I don't need to enable this option.
Thank you, I remember you posted about the high resistance for the VCC and GND traces on the Hiland board a long time ago but I can't find the post any longer.
Could you detail what the different mods achieve / what improvement you see in the behavior with your changes?
1: GND/VCC lower resistance traces
2: C10 input and C4 output capacitor for IC1 1117M3 voltage regulator, and what values do you use? Just recommended from the datasheet?
3: C3 capacitor, did you change it or just add the one that is directly on pins AVCC to AGND of the Atmega644?
4: C8 fixed capacitor for self-adjustment
5: Anything I missed? :) (except for precision test resistors, those are obvious what they do...)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on July 17, 2022, 09:17:03 am
Hi Yuriy,

... could you please tell us the values of the capacitors?

Regards Horst

P.S.

sorry for the overlap
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 17, 2022, 12:50:24 pm
Maybe it could even be improved to check if multiple displays are enabled, unless there is some use case for that?

Another good idea for the to-do list.

Lastly I think the "Clones" file should mention that you should change the MCU type in the Makefile from the default atmega328 for those models where that is relevant.

RTFM (please see README, section 'Building the Firmware')! ;)

The recommended setting of the low fuse for the Hiland M644 (ATmega 644, 8MHz) is 0xf7.
I know this is an old message but I have to ask why? Does this disable the external 8Mhz crystal and use the internal RC crystal, if so what is the purpose of this change, and if I misunderstood it can you please explain?

0xf7 enables the external quartz crystal and sets the prescaler to 1:1. The ATmega's default setting is internal RC oscillator and 8:1 prescaler.



Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 17, 2022, 03:53:13 pm
RTFM (please see README, section 'Building the Firmware')! ;)
Well the little note would not hurt to add to the "Clones" file IMO :)

0xf7 enables the external quartz crystal and sets the prescaler to 1:1. The ATmega's default setting is internal RC oscillator and 8:1 prescaler.
I had to re-read the Atmega644 datasheet about 28 times but I finally got it, the most important piece of the puzzle when reading the datasheet is this:
Quote from: Atmega644 datasheet
Note: 1. For all fuses “1” means unprogrammed while “0” means programmed.
With it programmed with 0xFF it sets all bits to "1" meaning unprogrammed, this means that the oscillator has a limited frequency range of 8 to 16MHz and startup mode: "slowly
rising power" this is a low power operation mode for the crystal oscillator.
With it programmed with 0xF7 instead the CKSEL3 bit is progammed and this means that the crystal oscillator has a frequency range of 0.4 to 20MHz with the same starup mode as before, this is a higher power mode for the crystal oscillator.

Here it is in practice, measured with a 100:1 probe to affect the drive level as little as possible, 1.3v vs 5.4v as you can see:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 17, 2022, 04:29:05 pm
Anything I missed? :) (except for precision test resistors, those are obvious what they do...)
You've got almost everything right. Here is the full scheme of changes and an enlarged view of the board. Enlarged view of T1, location in the case and the use of additional sockets, for the resonant method of measuring small inductances.
When selecting capacitances, one should take into account the change in capacitance and ESR values after heating the soldering points. It may take several hours to restore the original values. It depends on the type of ceramic. In the first two pictures, cold capacitors, in the next picture after warming up.
On my homemade Ttesters with ILI 9341 (built according to the Hiland scheme) I experimented with various changes in the Hiland scheme. To improve the stability of the readings and the correct measurement of the ESR of electrolytic and film capacitors, I selected the indicated capacitors, I don’t know their type, but they are soldered from cell phones of well-known companies. On a self-made capacitance meter, I can see the capacitance value of 5-6 characters. In the continuous measurement mode, you can judge the stability of the readings of these containers as they warm up. All significant changes obtained during experiments on homemade products were transferred to Hiland. Important, all changes are individual, adjusted to the installed ATmega644 and may have deviations from those indicated in this scheme. When selecting blocking containers, I paid special attention to the correct ESR. If the capacitance value is insufficient, the readings are underestimated. If the capacitance is too large, the readings are more than necessary. This is exactly for ATmega644, for circuits with ATmega328 it's the other way around.
This is a very simplified explanation.

P.S. Perhaps this is not true for most Hiland users. All my alterations are designed for firmware with increased up to 4 digits for measuring inductances and up to 5 digits for measuring capacitances. This was first worked out on homemade with ILI9341 in color, and then I transferred the changes to the sources for Hiland but the line length should be 20 characters. This is only possible with my font with a different display approach compared to the original "k" version. For this reason, I do not distribute the sources for the "k" version.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 17, 2022, 07:25:45 pm
I have a question about the rotary encoder on my Hiland 644.
It does not work so well with M-firmware, and I found something strange:
On channel B the voltage is 4.97v but on Channel A it is only 460mV.
I checked the pullup resistors R3 & R4 and they are 10K as they should.
And then the PB5 & PB7 resistors R6 & R8 are 1K as they should.
Is this normal behavior or what could be causing this?

In addition I measured the A and B channels with my scope like I did on my other component tester (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4259041/#msg4259041).
I used 10:1 probes for both channels, yes I know, it looks like I fucked up the probes or settings but it really is like this!
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1541278;image)

I used the Zener page because that does not write to the display: so it is much easier to scope gray codes, otherwise it looks like this:
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1541284;image)


You've got almost everything right. Here is the full scheme of changes and an enlarged view of the board.
Thanks Yuriy_K! If you could just describe what problems the different changes solve that would be nice, except the obvious ones of course :)
P.S: Do you have a link for a higher resolution version of the schematic than the one on Indman's Yandex site (https://disk.yandex.ru/d/yW8xa5NJgUo5z/Hiland%20M644/Schematic%20diagram/HilandM644.JPG)?
P.P.S: Two errors in that schematic I noticed: R17 connected to base of T3 should be named R19 and R3 and R4 should swap places.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 18, 2022, 06:04:16 am
P.S: Do you have a link for a higher resolution version of the schematic than the one on Indman's Yandex site (https://disk.yandex.ru/d/yW8xa5NJgUo5z/Hiland%20M644/Schematic%20diagram/HilandM644.JPG)?
P.P.S: Two errors in that schematic I noticed: R17 connected to base of T3 should be named R19 and R3 and R4 should swap places.
Thank you, I corrected the errors in the circuit that you found! I am attaching the corrected scheme in the highest possible quality for SPlan in jpg format
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 18, 2022, 10:50:11 am
I have a question about the rotary encoder on my Hiland 644.
It does not work so well with M-firmware, and I found something strange:
On channel B the voltage is 4.97v but on Channel A it is only 460mV.
I checked the pullup resistors R3 & R4 and they are 10K as they should.
And then the PB5 & PB7 resistors R6 & R8 are 1K as they should.
Is this normal behavior or what could be causing this?

In case of the Hiland M664 PB5 and 7 are shared between display and rotary encoder. Both I/O pins are set to output mode at startup, and when waiting for user feedback the pins are temporarily set to input mode to poll the rotary encoder every few ms. What you see can be normal at a specific time (pin setup).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 18, 2022, 11:14:51 am
This time we have done some work on the display output.

v1.47m:
- Fixed swapped resistor symbols in font_8x12t_iso8859-2_vfp.h and font_8x12t_iso8859-2_hf.h (reported by b0hoon@EEVblog).
- Added option to display quartz crystal symbol for LF/HF modes in extended frequency counter (UI_QUARTZ_CRYSTAL, suggested by indman@EEVblog).
- Added fonts font_8x12t_iso8859-2_hf.h (FONT_8X12T_ISO8859_2_HF) and font_8x16_iso8859-2_hf.h (FONT_8X16_ISO8859_2_HF, thanks to b0hoon@EEVblog).
- Fixed wrong reference of '\' in font_8x8_iso8859-2_h.h, broken diode symbol A-C and 'W' in font_6x8_iso8859-2_hf.h (Thanks to b0hoon@EEVblog).
- Added option to display a Zener diode symbol in any Zener check (UI_ZENER_DIODE, suggested by indman@EEVblog).
- New 32x39 symbol set to match 26 pixel high fonts (SYMBOLS_32X39_HF, thanks to indman@EEVblog).
- Added options to auto-hold ESR and inductance for C and L monitor (SW_MONITOR_HOLD_ESR, SW_MONITOR_HOLD_L, suggested by theHWcave@EEVblog).
- Added character translations for inversed pin numbers to Serial_Char().
- Added option for /RESX line on separate MCU port to ST7735 driver (LCD_RES_PORT, LCD_RES_DDR, based on idea from lhlad@EEVblog).
- Added option to display a question mark symbol in case of a failed test run (UI_QUESTION_MARK, suggested by indman@EEVblog).
- Added symbols for question mark, Zener diode and quartz crystal to all symbol sets (thanks to indman@EEVblog).
- Added additional positioning flags for fancy pinout (PIN_CENTER, PIN_ALT_CENTER, suggested by indman@EEVblog).
- Display small diode symbol in front of Vf for MOSFETs and IGBTs (suggested by indman@EEVblog).
- Added numbers 1-3 and character x with reversed color plus degree character to font_8x16alt_win1251_hf.h. Also updated 1-3 and x with reversed color in font_8x8alt_win1251_vf.h. Same for font_16x26_win1251_hf.h (thanks to indman@EEVblog).
- Added option to disable display of text based pinout of the body diode for MOSTFETs (UI_NO_BODYDIODE_TEXTPINOUT, suggested by indman@EEVblog).
- Added symbol set 32x39 (SYMBOLS_32X39_HF, thanks to indman@EEVblog).
- Added alternative symbols sets 24x24 (SYMBOLS_24X24_ALT1_H, SYMBOLS_24X24_ALT2_H, SYMBOLS_24X24_ALT1_HF, SYMBOLS_24X24_ALT2_HF, SYMBOLS_24X24_ALT1_VFP, SYMBOLS_24X24_ALT2_VFP, SYMBOLS_24X24_ALT1_VP_F and
SYMBOLS_24X24_ALT12_VP_F), 30x32 (SYMBOLS_30X32_ALT1_HF and SYMBOLS_30X32_ALT2_HF) and 32x32 (SYMBOLS_32X32_ALT1_HF and SYMBOLS_32X32_ALT2_HF, thanks to indman@EEVblog).
- Added option to fancy pinout to show right-hand probe numbers above/below the symbol (UI_PINOUT_ALT, suggested by indman@EEVblog).
- Fixed issue in FontTest() with missing spaces for some display drivers.
- Added test output of component symbols (SW_SYMBOL_TEST, suggested by indman@EEVblog).
- Updated Russian texts (thanks to indman@EEVblog).
- Fixed missing ')' character and broken '*' in font_10x16_hf.h (reported by pepe10000@EEVblog).

Please download at:
- https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
- https://github.com/kubi48/TransistorTester-source/tree/master/Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 18, 2022, 02:02:43 pm
I have a question about the rotary encoder on my Hiland 644.
It does not work so well with M-firmware, and I found something strange:
On channel B the voltage is 4.97v but on Channel A it is only 460mV.
I checked the pullup resistors R3 & R4 and they are 10K as they should.
And then the PB5 & PB7 resistors R6 & R8 are 1K as they should.
Is this normal behavior or what could be causing this?

In case of the Hiland M664 PB5 and 7 are shared between display and rotary encoder. Both I/O pins are set to output mode at startup, and when waiting for user feedback the pins are temporarily set to input mode to poll the rotary encoder every few ms. What you see can be normal at a specific time (pin setup).
I tested Indman's 8MHz K-firmware build for my Hiland now and the result is interesting:
The encoder works fine with this build, it also did with the "original Chinese" firmware (yes it's an oxymoron I know!)

When no writes occur to the display the voltage is pulled up to ca 4.1v for both channels.
This was 460mV for Channel A and 5v for Channel B with M-firmware.
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1542256;image)

When writes do occur they are at 5v with both firmwares.
I think the difference is caused by the pullup configuration.
But I am not sure what setting specifically would affect it.
I posted a small exert from Indman's Makefile below, the full is available on his site (https://disk.yandex.ru/d/yW8xa5NJgUo5z/Hiland%20M644/Firmware/Karl-Heinz%20Kübbeler%20/English/8Mhz).
Maybe someone smarter than me can look at this and give me their opinion :)
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1542262;image)

Code: [Select]
# With the option LCD_SPI_OPEN_COL the data signals of the SPI interface are not switched to VCC.
# With option LCD_SPI_OPEN_COL the signals are switched to GND only, for high signals the pullup resistors
# of the ATmega are used. For the RESET signal a external pull-up resistor is required, if the
# option PULLUP_DISABLE is set. For the other signals the internal pullup resistors of the ATmega
# are temporary used, even if option PULLUP_DISABLE is set.
#CFLAGS += -DLCD_SPI_OPEN_COL

# If LCD_ST7565 option is used: Set the resitor ratio for the internal
# voltage regulator. Supported value range: 0..7.
# Good values are e.g. 4 or 7. If unsure just have a try.
LCD_ST7565_RESISTOR_RATIO = 4


# The PULLUP_DISABLE option disable the pull-up Resistors of IO-Ports.
# To use this option a external pull-up Resistor (10k to 30k)
# from Pin 13 to VCC must be installed!
CFLAGS += -DPULLUP_DISABLE

# The sleep mode of the ATmega168 or ATmega328 is normally used by the software to save current.
# You can inhibit this with the option INHIBIT_SLEEP_MODE .
#CFLAGS += -DINHIBIT_SLEEP_MODE

Here is my understanding of this:
LCD_SPI_OPEN_COL is not configured, so it means the SPI interface is switched to VCC
PULLUP_DISABLE is configured, the pin should be 26 on the Atmega644 I believe, this has a 27k pullup to VCC.
LCD_ST7565_RESISTOR_RATIO is set to 4, I guess this could also be affecting the drive level?
Corrections for my interpretation of this are more than welcome! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 18, 2022, 04:23:38 pm
I tested Indman's 8MHz K-firmware build for my Hiland now and the result is interesting:
The encoder works fine with this build, it also did with the "original Chinese" firmware (yes it's an oxymoron I know!)

My Hiland M644's rotary encoder works fine with the m-firmware. :-// Configuration issue? If the encoder works intermittent try different values for ENCODER_PULSES and ENCODER_STEPS, in case it's a different encoder type. BTW, the Chinese firmware is a modified k-firmware.

Here is my understanding of this:
LCD_SPI_OPEN_COL is not configured, so it means the SPI interface is switched to VCC
PULLUP_DISABLE is configured, the pin should be 26 on the Atmega644 I believe, this has a 27k pullup to VCC.
LCD_ST7565_RESISTOR_RATIO is set to 4, I guess this could also be affecting the drive level?
Corrections for my interpretation of this are more than welcome! :)

PULLUP_DISABLE disables the internal I/O pull-up resistors (20-50k) globally. And LCD_ST7565_RESISTOR_RATIO is meant for the ST7565's internal voltage regulator (contrast etc).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 18, 2022, 05:03:51 pm
My Hiland M644's rotary encoder works fine with the m-firmware. :-// Configuration issue? If the encoder works intermittent try different values for ENCODER_PULSES and ENCODER_STEPS, in case it's a different encoder type. BTW, the Chinese firmware is a modified k-firmware.
Yes I've already tried several different settings for the encoder but it does not really change much.
Here is a picture of moving the encoder only one of the 24 steps / detents it has:
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1542403;image)


PULLUP_DISABLE disables the internal I/O pull-up resistors (20-50k) globally. And LCD_ST7565_RESISTOR_RATIO is meant for the ST7565's internal voltage regulator (contrast etc).
Yes but how does this compare with the settings in your M-firmware?
I mean can we make similar settings there too or is it not configurable?
Because I think the 460mV signal level could be an issue since it is only on Channel A and that does not happen with K-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 18, 2022, 06:44:38 pm
Yes but how does this compare with the settings in your M-firmware?
I mean can we make similar settings there too or is it not configurable?

In the m-firmware the ATmega's internal I/O pull-up resistors are disabled anyway (not a configuration option). The ST7565's resistor ratio has no impact on the interfaces's logic levels. And the open collector style switching of SPI lines is not supported.

Because I think the 460mV signal level could be an issue since it is only on Channel A and that does not happen with K-firmware.

As I tried to explain already, that can be normal at a specific time period, e.g. before or after probing the rotary encoder when PB5 and 7 are in output mode and one is set high and the other one low. If the settings are fine then it's most likely a cheap rotary encoder (we've discussed this just a few posts back). The k-firmware is more tolerant of poorly switching encoders, while the m-firmware ignores glitches (nothing happens, intended design). A typical symptom is that the encoder works fine in one direction, but not in the other direction. Or the tester reacts only after turning the encoder several steps/detents. Looking at your scope images it seems that one contact is switching too briefly in comparison to the other one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 18, 2022, 07:26:29 pm
Thanks Madires, my hope was that there would be some configuration mistake that causes it, but it seems from your explanation that I have the same in both k and m firmware.
I honestly think this encoder is not so bad, the one on my other meter that I replaced with a genuine Bourns was terrible.
But this one I think is fine, still debating if I should replace it or just live with it, if I do would you like me to send this one to you?
Because this one unlike the other one I think should be handled by the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 18, 2022, 11:32:22 pm
I encountered a problem with my Hiland 644 tester now, I have not started doing any hardware mods yet.
I was just making sure everything is ok before I start, and it is not!
The R0 values are all showing as 0.00Ω with Indman's K-firmware (https://disk.yandex.ru/d/yW8xa5NJgUo5z/Hiland%20M644/Firmware/Karl-Heinz%20Kübbeler%20/English/8Mhz) as you can see in the attached picture.
It was 0.27 0.26 0.27Ω with the original K-firmware.
If I instead use M-Firmware it reports 0.22Ω during the self adjustment for R0 and that sounds more reasonable!
Has anyone got any ideas?
I notice a compile value in the K-Firmware Makefile below, would it apply during calibration for R0 values also?
Could this be the reason?
Code: [Select]
# The ESR_ZERO value define the zero value of ESR measurement (units = 0.01 Ohm).
CFLAGS += -DESR_ZERO=20
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 19, 2022, 05:33:20 am
Per Hansson,before conducting experiments and drawing any practical conclusions about comparing the results, you need to remember and do just 1 important thing - YOU NEED TO INSTALL A HIGH-QUALITY(NO CHINA) STABILIZER + 5V in the TESTER!
99% of all complaints(problems) and incomprehensible measurement results on this tester are associated with unstable and poorly filtered CPU voltage! Remember ALL this and hang this reminder in front of you on the monitor. :)

Here is an answer from Karl-Heinz to a similar question that I also asked him about not too long ago:
"The R0 measurement is done with the function GetESR.S. For the ESR measurement of capacitors with low capacity the current pulses used for measurement are short.The newer 1.13k use a shorter puls-length than the 1.12k.
The pulse is shortened for measure capacitors above 20nF instead of above 90nF for
the older version.The timing of the ADC sampling must match to 1 clock cycle for correct mesurement results
of little capacitors because the voltage is rising fast.
But a short current pulse can also make problems, if the VCC voltage is unstable.
You can try to add additional capacitors to make the VCC voltage more stable to
prevent measurement errors for this reason (short current puls)."
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 19, 2022, 10:15:44 am
Thanks Indman, I found the post where this is mentioned:
https://www.mikrocontroller.net/topic/transistortester-avr?page=single#5644769 (https://www.mikrocontroller.net/topic/transistortester-avr?page=single#5644769)

But a bit further down this is then stated:
Quote
> Der Fehler tritt auch bei größeren Kondensatoren auf - Werte < 0,8 Ohm
> werden als 0.00 Ohm angezeigt - erst darüber sind die Werte mit denen
> der "328er" vergleichbar.

Die Ursache war eine falsche Abfrage in der Funktion GetESR.S speziell für den ATmega644.
https://www.mikrocontroller.net/topic/transistortester-avr?page=single#5775968 (https://www.mikrocontroller.net/topic/transistortester-avr?page=single#5775968)

So I tested to recompile the latest git version of K-firmware and then the R0 test is fine!
I will now make some tests to replace the silly 100nF capacitors for the 1117M3 regulator because as you say it is not really stable!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 19, 2022, 11:56:45 am
I honestly think this encoder is not so bad, the one on my other meter that I replaced with a genuine Bourns was terrible.
But this one I think is fine, still debating if I should replace it or just live with it, if I do would you like me to send this one to you?
Because this one unlike the other one I think should be handled by the firmware.

I wouldn't call a rotary encoder working fine when one of the two switching contacts creates pulses half as long as the other. From the software point of view, a commonly used algorithm (simple, taking a shortcut) for reading rotary encoders would be able to read that specific encoder ok-ish, but it has problems with encoders creating lots of switch bouncing. One step/detent could be detected as two or more. Very annoying when you have a dynamic control taking the turning speed into account (as the m-firmware does for some functions). The m-firmware's algorithm takes a different approach which results in ignoring poor switching signals. So bad encoders become more apparent.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 19, 2022, 02:25:54 pm
I have now replaced the input and output capacitors on my Hiland 644 tester, I started with only C4 (the output capacitor).
This completely fixed the stability problems, before the ESR or Ohm value would "hunt" up and down if I left the tester running.
Now it is stable! It would even randomly corrupt the calibration data and say the meter is uncalibrated, that is was fixed too...
I also changed C10 (the input capacitor) for good measure but noticed no difference.
(That said it could help when the battery gets weaker as the battery internal resistance goes up).

Here is a recap of events:
Meter would show 0Ω for all R0 tests with the Hiland K-Firmware Rev804En(8x12t)8Mhz.zip from Indman's repository:
This was fixed by compiling the latest version, no hardware changes necessary! (See my previous post for explanation).
This also changed the "REF_C" test value from 23 down to 18, all other values had only minimal changes.

Meter would not show a stable reading, and sometimes would hang including corrupting calibration data:
This was fixed by replacing the 100nF output filter capacitor C4 with a 4.7µF ceramic capacitor taken from a PC motherboard.
The capacitor ESR reads 1.1Ω @ 1kHz, 0.4Ω @ 10kHz and 0.33Ω @ 100kHz using my Agilent U1733C.
The pads are ca 2.3mm wide so a 0805 capacitor does fit tightly, but a 0603 would be a better fit.
If also replacing the input capacitor C10 keep in mind it needs to handle the higher battery voltage!


I wouldn't call a rotary encoder working fine when one of the two switching contacts creates pulses half as long as the other.
Well, if you look at the scope shots from the genuine Bourns encoder I installed on my other meter a few weeks ago it is very similar in that regard:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg4259041/#msg4259041
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 19, 2022, 08:42:35 pm
I made some continued tests: the Hiland 644 tester now matches the "original Chinese" firmware.
But it is still no match for my old venerable GM328R meter!
So I changed C3 to also be a 4.7µF ceramic, this did actually improve the meter further, measurement stability increased.
However the meter still shows invalid ESR values (0.00Ω) for some caps that my old Atmega328 based meter handles fine.
So I thought this is probably due to the integrated calibration cap C8 which also is a regular 100nF ceramic, an obvious issue...
I replaced it with a nice Wima 470nF film capacitor, however that made surprisingly little difference for the calibration!

So I thought maybe it is because of the 8MHz crystal, my other meter has a 20MHz crystal and this affect the SamplingADC function.
So I swapped it for a 16MHz crystal however then the issue with the R0 values being 0.00Ω came back :(
I have spent allot of time looking at the GetESR.S file in K-Firmware because I think the issue is there.
If you look at the value "FAKTOR_ESR" it is defined to 30250 if the processor type is Atmega644.
Otherwise it will be defined as 550000
Then we get to a if statement if the CPU speed is 16MHz
However here all definitions are commented out!
I'm no expert on C code but doesn't this mean the previous value should still be valid then?
There is a further confusion at the beginning of the file: #if (PROCESSOR_TYP == 640) || (PROCESSOR_TYP == 1280)
Well, 640 doesn't equal 644 so I guess that statement will be false, but then again the statement would not change due to the processor speed...
Can someone that has a bit better coding skills than me take a look at this?
https://github.com/kubi48/TransistorTester-source/blob/master/trunk/GetESR.S

P.S: Are the changelogs for the old SVN repository still available somewhere?


EDIT: I tried a couple edits of GetESR.S but could not get it right.
Then I found this post linked below by Yuriy_K and his attached HEX file in "Hiland_M644.zip" from post #810901 works great!
I'm unable to compile that version though when using his version of GetESR.S with the latest git release so too much has changed I guess :(
https://vrtp.ru/index.php?showtopic=25020&st=1170#
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 20, 2022, 05:27:35 am
Per Hansson,use m-firmware, it doesn't have problems with GetESR because R0 is determined by another method  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 20, 2022, 06:32:25 am
Use m-firmware, it doesn't have problems with GetESR because R0 is determined by another method  ;D
Yes Indman that is what I intend to do, because I want this meter to have all the nice extras of M-firmware.
However I also want to help other people out that want to run K-firmware on it.
It seems to me that this change I mentioned below only applies when the clockspeed is 8MHz, not 16MHz:

Quote
> Der Fehler tritt auch bei größeren Kondensatoren auf - Werte < 0,8 Ohm
> werden als 0.00 Ohm angezeigt - erst darüber sind die Werte mit denen
> der "328er" vergleichbar.

Die Ursache war eine falsche Abfrage in der Funktion GetESR.S speziell für den ATmega644.
https://www.mikrocontroller.net/topic/transistortester-avr?page=single#5775968 (https://www.mikrocontroller.net/topic/transistortester-avr?page=single#5775968)

So I tested to recompile the latest git version of K-firmware and then the R0 test is fine!
I will now make some tests to replace the silly 100nF capacitors for the 1117M3 regulator because as you say it is not really stable!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 20, 2022, 07:51:43 am
However I also want to help other people out that want to run K-firmware on it.
It seems to me that this change I mentioned below only applies when the clockspeed is 8MHz, not 16MHz:
To compare measurements of different capacitances on
ATMega328 - top row,
ATmega644 - middle row,
Hiland M644 - bottom row.
All Ttesters with 16MHz crystal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 20, 2022, 08:15:42 am
So that now there are no questions why the ESR measurement for non-electrolytic capacitors differs by 10-100 times on m-firmware compared to k-firmware, I will explain. ESR measurement for this type of capacitors and for m-firmware is equivalent to measuring with a sinusoidal signal at a frequency of 1kHz LCR-bridge, for k-firmware this frequency is approximately equal to 10-20kHz. Also a very important factor that greatly affects these measurements is the quality and batch of the processor used. The Chinese processors that I have had experience with have a huge variation in parameters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Felipe Lacerda on July 22, 2022, 04:26:44 am
So that now there are no questions why the ESR measurement for non-electrolytic capacitors differs by 10-100 times on m-firmware compared to k-firmware, I will explain. ESR measurement for this type of capacitors and for m-firmware is equivalent to measuring with a sinusoidal signal at a frequency of 1kHz LCR-bridge, for k-firmware this frequency is approximately equal to 10-20kHz. Also a very important factor that greatly affects these measurements is the quality and batch of the processor used. The Chinese processors that I have had experience with have a huge variation in parameters.

Does this justify these measurements with 0805 X5R/X7R?

New parts, I tried to use the shortest lead possible.
All with the same 0.33k \$\Omega\$ ESR.   |O
10uf displays 11.14uf, on keysight multimeter it displays 9.1uf.

Did I get junk parts? Or is the meter crazy?  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 22, 2022, 08:39:38 am
Does this justify these measurements with 0805 X5R/X7R?
No.
What indman explains is that the two different open source firmware have a different way of testing small capacitors:
Only K-firmware have "SamplingADC" and this gives more "expected" results (compared to capacitor datasheets) vs M-firmware.
For example I tested a 4.7µF ceramic capacitor SMD now on my Hiland 644 and it gives these results:
4588nF 0.05Ω 0.3% vloss
Compared with my Agilent U1733C that I posted above in my post #7759:
ESR reads 1.1Ω @ 1kHz, 0.4Ω @ 10kHz and 0.33Ω @ 100kHz using my Agilent U1733C, it reads capacitance as 4.535µF @ 100Hz
So I would say something is wrong with your meter, have you calibrated it by shorting the three test points?
If so please show the results of "show data" in the meters menu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 22, 2022, 09:16:16 am
For those who want to transfer their Hiland to a 16 MHz crystal. I can’t transfer the source codes, there are too many changes, but I collected the required large font for my changes. Here is the firmware and examples of capacitance measurements from the previous message and others.

P.S. Fixed JFET display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 22, 2022, 09:22:03 am
So I thought maybe it is because of the 8MHz crystal, my other meter has a 20MHz crystal and this affect the SamplingADC function.
So I swapped it for a 16MHz crystal however then the issue with the R0 values being 0.00Ω came back :(
I have spent allot of time looking at the GetESR.S file in K-Firmware because I think the issue is there.
If you look at the value "FAKTOR_ESR" it is defined to 30250 if the processor type is Atmega644.
Otherwise it will be defined as 550000
I found a repository that had all the old changes from the SVN repository listed.
This change that fixed the problems with the "R0" test values being 0.00Ω at 8MHz is here in SVN 809:
https://github.com/M-Reimer/transistortester/commit/00a2d497d1d8349cb4ce15f59deb7accb49fe412

Then we get to a if statement if the CPU speed is 16MHz
However here all definitions are commented out!
I'm no expert on C code but doesn't this mean the previous value should still be valid then?
As for this I tested it, yes the section with "#if F_CPU == 16000000UL" under the "FAKTOR_ESR" section is redundant, deleting it does not affect the code.
It looks like Karl-Heinz was testing other values for "FAKTOR_ESR" at 16MHz but never commited to them.

There is a further confusion at the beginning of the file: #if (PROCESSOR_TYP == 640) || (PROCESSOR_TYP == 1280)
Well, 640 doesn't equal 644 so I guess that statement will be false, but then again the statement would not change due to the processor speed...
Can someone that has a bit better coding skills than me take a look at this?
https://github.com/kubi48/TransistorTester-source/blob/master/trunk/GetESR.S

P.S: Are the changelogs for the old SVN repository still available somewhere?
The commit that shows this fix is in SVN 808.
It seems it should really be 640 and 1280 and not 644 and 1280 like it was in the previous versions.
Because these two processors are from the same range I guess so this is fine...
https://github.com/M-Reimer/transistortester/commit/6322ea82b5f0f55bf6382b8c65114878a33279ac

EDIT: I tried a couple edits of GetESR.S but could not get it right.
Then I found this post linked below by Yuriy_K and his attached HEX file in "Hiland_M644.zip" from post #810901 works great!
I'm unable to compile that version though when using his version of GetESR.S with the latest git release so too much has changed I guess :(
https://vrtp.ru/index.php?showtopic=25020&st=1170#
I found a further version by Yuriy_K in his post #865595 file "Forum.zip" that works fine: https://vrtp.ru/index.php?showtopic=25020&st=1320

I have tried to get the same good values as with Yuriy_K's firmware by compiling the latest from GIT and trying different values for "FAKTOR_ESR".
However I am not able to do it: whatever I change "FAKTOR_ESR" to has little effect, and the result is always that some small film caps show 0.00 ESR.
I also realized the "R0" calibration values are not stable in the one I compile, but it is in Yuriy_K's firmware they are ALWAYS 0.30Ω to 0.31Ω!
A further confusion is that Yuriy_K uses FAKTOR_ESR of ca 550000 which is the standard value for all Atmegas, while Karl-Heinz uses 30250 for the Atmega644, very big difference!

Before I realized this I actually added back the 100nF caps at C3 C4 & C10 ontop of my new 4.6µF capacitors, but it had no effect.
I also realized that the boost converter draws around 45mA (consumption rises from ca 35mA to 80mA) when it starts.
What is bad about this is that the boost converter sits on the regulated 5v line, and when you press the button to start the test it briefly activates.
This probably is a very big reason for the problems with the cheap Chinese regulators, this is simply not a good design at all!
If you look in the original 644 design included in Karl-Heinz documentation the boost converter has its own DC>DC regulator fed from the battery.
So it does not affect the stabilized 5v for the processor at all, this is especially bad in the Hiland design where the penny pinchers used 100nF caps when they really should be 10µF!!!
That said I removed R9 to disable the boost converter: this did not seem to have any discernible effect, my own compiled firmware still gives unstable calibration values.
While Yuriy_K's firmware has given consistent results with all these changes implemented!
Please Yuriy_K's: can you (for my own sanity) post what GIT version you used to compile your firmware that I linked before?
Either "Hiland_16_en.zip" from: October 27 2020 or "Hiland_M644.zip" from: March 10 2019?

P.S: Maybe a nice design addition for M-Firmware would be to be able to dedicate one processor pin for starting the boost converter so it only starts when you are in the Zener menu and press the button?
All that would be required is to lift R9 and attach it to one of the Atmega644 free outputs, this would also save allot of battery power since it is a rarely used function that draws allot of current?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 22, 2022, 09:32:36 am
Did I get junk parts? Or is the meter crazy?  :palm:
Per Hansson and Felipe Lacerda,the reason for the false readings is hidden elsewhere
1. The T7 clone shown in the photo is based on the Chinese analogue ATMega328 -LGT8F328P
2. Factory firmware for these and similar clones, T1-T7 is not at all a copy of the author's firmware k-firmware and m-firmware. Many functions and options in the Chinese firmware are removed in order to get a beautiful picture on the screen instead.
And in this particular measurement example, we see that the ESR measurement function was copied by Chinese friends for the LGT8F328P processor unsuccessfully.
3. Quality SMD ceramics have low ESR values, as evidenced by the graph below, as well as a few measurements I made on my DTU-1701 clone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 22, 2022, 10:13:43 am
Please Yuriy_K's: can you (for my own sanity) post what GIT version you used to compile your firmware that I linked before?
Try the firmware from my previous post. Since then, both Karl-Heinz and I have made many changes to the source code and not only to GetESR. Not all changes in the source texts were indicated by Karl-Heinz, I had to search on my own and make them to my source codes, which differ significantly from the author's ones.

P.S. In my homemade Ttesters, I use a simple switch to turn off the boost converter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 22, 2022, 11:38:16 am
P.S: Maybe a nice design addition for M-Firmware would be to be able to dedicate one processor pin for starting the boost converter so it only starts when you are in the Zener menu and press the button?
All that would be required is to lift R9 and attach it to one of the Atmega644 free outputs, this would also save allot of battery power since it is a rarely used function that draws allot of current?

I agree, it would better to switch on the boost converter only when checking Zener diodes. I'll put it on the to-do list. The current design (either switched by the test button or running all the time) stems from the lack of free pins of the ATmega328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on July 22, 2022, 01:49:02 pm
Now that indman refreshed the LGT8F328P existence for some T7s (maybe other clones too), I wonder, has anyone ported the OSHW to this "arguably improved" 32KB derivative via SWD? And if so, were some benefits obtained against the traditional ATmega328p?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 22, 2022, 02:59:14 pm
And if so, were some benefits obtained against the traditional ATmega328p?
I think that for now we cannot talk about any advantages of the Chinese version compared to the classic ATMEL.
On the contrary, I think that if we completaly and thoroughly test all the modes of operation of the new tester, we will find many more unpleasant surprises. The same can be said about the new DSO-TC2 hybrid device, in which the Chinese analogue of STM is already installed and the k-firmware code is partially copied to the new platform. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 22, 2022, 03:27:34 pm
Now that indman refreshed the LGT8F328P existence for some T7s (maybe other clones too), I wonder, has anyone ported the OSHW to this "arguably improved" 32KB derivative via SWD? And if so, were some benefits obtained against the traditional ATmega328p?

I haven't worked with that ATmega clone yet. A fourth timer and a 12 bit ADC could be a benefit, but I have no idea how the ADC performs. We also would need to spend some effort on checking critical things which require perfect timing and figure out differences. The flash size limit of 32k is a drawback, and I don't think it would make much sense to invest time in this for the foreseeable future.
Title: Re: $20 LCR ESR Transistor checker project
Post by: macboy on July 22, 2022, 03:40:15 pm
I picked up a GM328A kit with 160x120 color display, rotary encoder, and TL431 reference. I didn't like the original firmware so I built my own versions of both the m and k firmware discussed here.

I found the update of the display to be too slow, so I did a couple things: upgraded from the original 8 MHz crystal and fixed some code. I ended up running at 27 MHz (significant overclocking but it works) and needed to update some timing related things for correct readings. In particular, sampling_cap.c required trivial but important update to support this specific frequency. The ADC is running at ~210 kHz clock, slightly beyond spec for best accuracy, but we over-sample and average anyway so a little bit of LSb noise isn't so bad.

The other thing I did was "fix" the menu system (K firmware). I tried switching to the page mode menu, but it was still way too slow to respond to the rotary control. I found that although most of the screen is not changing content, the entire screen is re-drawn each time the control is moved. So I fixed that: if the 'page' doesn't change, then draw only the '>' or ' ' at the first char of each line, to indicate the selection. This was only 3 lines of code including a variable declaration. I also changed the rotary encoder input to not wait for additional increments, but return on the first one. The combination of these two changes makes the menu instantly responsive.

As I played I thought it would be great to add measurement of VCEsat (Voltage of Collector-Emitter at saturation) for BJTs. I chose to do this in the M firmware as the code looked better structured and easier to follow. The web of #ifdef statements in the K firmware can be hard to follow. I only implemented the NPN so far, but it works well. I use the 680R to drive the base with about 7 mA in a common emitter type circuit. Originally, I used the 680R to limit Ic collector current, but this small ~7 mA Ic, plus Ic/Ib ratio nearly =1 gave lower (sometimes much lower) than expected results for measured VCEsat. So I switched to using no R at all in the collector-emitter path. Only the internal resistance of the pin drivers (20-24 Ohm) and test leads will limit current, so it ends up at around 80 to 100 mA (depending on VCEsat slightly). The Ic/Ib is now about 10 to 14, closer to ideal for this measurement about 30, still lower than the ideal ratio of 10 (used in many datasheets). The high Ic is far exceeding the max specified I/O pin current, but it is for only a few milliseconds at a time during the test. So far I haven't blown up any '328Ps. The Ic current is high enough that even the test probe resistance must be accounted for in calculations. With the low-ish base current, DC gain must be >>30 (I'd say at least 100) to ensure good saturation. Case in point: result with the low gain 2SC2625, see below.

Obviously I am willing to share my code changes, but I don't know the best way to do that.

Left to Right:
2N2222 (TO-92), 2SD2394 (TO-220), 2SC2625 (TO-247)
I suppose I should duplicate the test conditions (Ib and Ic) on the bench and verify the results with the same set of devices. In fact I'll do that now, and update this post with the results.

Bench Test Update:
For 2N2222, I measured 250 mV at 95 mA Ic, roughly 3 mA Ib.
For D2394, I measured 63 mV at 109 mA Ic, roughly 3 mA Ib.
For 2SC2625, due to its low gain (20) was not in saturation due to the small (~3 mA) base current. On the bench, increasing base current to about 6 mA resulted in saturation with about 206 mV across C-E. The tester can't drive this base current due to the ~20 Ohms RIL (I/O pin internal resistance) acting as an emitter degeneration resistor, lifting the emitter voltage to about ~ 2 V, and the base voltage to about ~2.6 V.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 22, 2022, 04:31:42 pm
I have updated the comparison table of the most popular clones, taking into account the release of the new 1.47m and the addition of another clone variant LCR-TC1(T7)ATMega328DIP! To my resource https://yadi.sk/d/yW8xa5NJgUo5z added working English and Russian firmware 1.45m as well as its schematic diagram for this clone. I have also updated the Russian-language pdf format instruction for 1.47m. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 22, 2022, 05:39:30 pm
Obviously I am willing to share my code changes, but I don't know the best way to do that.

One way would be to send an email to the address noted in the documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lhlad on July 22, 2022, 08:08:54 pm
Hello

Working 1.46m for LCR T7H clone, picture attached.

Added ATAR_TC1_U4 config option to make it play nice with U4/5 firmware. 
I got same problem as others trying to use the replacment U4/5 firmware, mainly power off straight away after first probe. 
Took a while to work out what was going on as both work as expected independently.

See https://gitlab.com/a11059/t7h_644_m.git  Scroll down to see info.

Repo includes schematic and more images of unit.
Also a link to an SDCC compatable version of U4 firmware.

Hope some find it usefull.



Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 22, 2022, 08:58:50 pm
I'll add your workaround to the next version. Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on July 22, 2022, 09:15:34 pm
Thanks indman and madires for your comments on the previous page about the ATmega clone, and also about the STM clone I think nobody had mentioned here before.

So from your valuable comments no plans on working on those for the short term. But anyways we should keep an eye on what the vendors puts on the shelves the next months, so maybe the market could shift in the medium run, we will have to wait.

And as always, thank you for your support.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mclute0 on July 22, 2022, 09:43:35 pm
I have some spare AVR128DB28-I/SP and they seem like a great MCU for these testers given how hard to find the atmega28pu chips are. maybe make a plugin socket to translate the pins for a prototype?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 22, 2022, 10:52:40 pm
That AVR128DB28 looks much more interesting than the ATmega clone mentioned before. 12 bit ADC, DAC, built-in level shifting and some more features. EEPROM is a bit meagre.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 22, 2022, 11:07:14 pm
But anyways we should keep an eye on what the vendors puts on the shelves the next months, so maybe the market could shift in the medium run, we will have to wait.

I concur! For the foreseeable future we'll stay with the ATmega328 and 644 (324, 1284).
Title: Re: $20 LCR ESR Transistor checker project
Post by: N9XYP on July 23, 2022, 12:08:42 am
Now that indman refreshed the LGT8F328P existence for some T7s (maybe other clones too), I wonder, has anyone ported the OSHW to this "arguably improved" 32KB derivative via SWD? And if so, were some benefits obtained against the traditional ATmega328p?

over on GitHub = https://github.com/DurandA/transistor-tester-lgt328p

and to make working with the timers easier - https://dbuezas.github.io/arduino-web-timers/#mcu=LGT8F328P&timer=0

Don't forget the DAC, 80mA pins, computing accelerator (math routines) and a differential amplifier
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on July 23, 2022, 01:06:46 am
Interesting. Have you tried it?

From a quick glimpse of the files, it looks like DurandA took 1.42m and made some equivalences between the lgt and the 328. Maybe one of the developers could take a better look of that (provided they want to spend a little time to further study this fork).
What I miss most is it seems he didn't update the documentation to help us non-programmers get better bearings.

Anyways, thanks for the hint.

Don't forget the DAC, 80mA pins, computing accelerator (math routines) and a differential amplifier
Regarding the 80mA, unless the circuit is modified to reduce the low-value resistors to 68R or something like that, and consequently improved power supply and stabilization, it wouldn't benefit the "standard" component tester.  And for the rest of features, I guess it would require a lot more of coding and/or hardware mods.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 23, 2022, 01:47:34 pm
DurandA did only a few modifications, mainly adapted Makefile, ADC clock rates and the waitX() functions. The asm commands rcall and ret apparently need four cycles less. So a few time critical functions have to be adapted too. If the LGT8F328P matches the ATmega328 really well, maybe there isn't much more to be done.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 24, 2022, 02:15:53 am
The other thing I did was "fix" the menu system (K firmware). I tried switching to the page mode menu, but it was still way too slow to respond to the rotary control. I found that although most of the screen is not changing content, the entire screen is re-drawn each time the control is moved. So I fixed that: if the 'page' doesn't change, then draw only the '>' or ' ' at the first char of each line, to indicate the selection. This was only 3 lines of code including a variable declaration.
I really like the page mode, can you post the changes you did for this?
Also cool to read about your VCEsat tests, good work! :)

I have some spare AVR128DB28-I/SP and they seem like a great MCU for these testers given how hard to find the atmega28pu chips are. maybe make a plugin socket to translate the pins for a prototype?
That AVR128DB28 looks much more interesting than the ATmega clone mentioned before. 12 bit ADC, DAC, built-in level shifting and some more features. EEPROM is a bit meagre.
madires: 128KB flash though, very very nice!
mclute0: I think making an interposer board for it would be nice so it could be used as a drop-in replacement for Atmega328P boards that have the microcontroller in a socket!

Please Yuriy_K's: can you (for my own sanity) post what GIT version you used to compile your firmware that I linked before?
Try the firmware from my previous post. Since then, both Karl-Heinz and I have made many changes to the source code and not only to GetESR. Not all changes in the source texts were indicated by Karl-Heinz, I had to search on my own and make them to my source codes, which differ significantly from the author's ones.
Thanks!
You posted at the same time I had written my very long post that I doubt few people have the patience to read through ;)
I would be very grateful if you could give some idea where you think the issue is with the K-firmware that I see.
Am I on the right path with trying to adjust "FAKTOR_ESR" or was there some other much more imprtant thing you had to change?
Because it would be much nicer if the problem can be reported back to Karl-Heinz so he can fix it in the official source code!
Remember: it worked fine at 8MHz after upgrade to SVN 809 (https://github.com/M-Reimer/transistortester/commit/00a2d497d1d8349cb4ce15f59deb7accb49fe412).
Only 16MHz operation causes the R0 values to be reported as 0.00Ω after that, recapped in these quotes here:

I encountered a problem with my Hiland 644 tester now, I have not started doing any hardware mods yet.
I was just making sure everything is ok before I start, and it is not!
The R0 values are all showing as 0.00Ω with Indman's K-firmware (https://disk.yandex.ru/d/yW8xa5NJgUo5z/Hiland%20M644/Firmware/Karl-Heinz%20Kübbeler%20/English/8Mhz) as you can see in the attached picture.
It was 0.27 0.26 0.27Ω with the original K-firmware.

Thanks Indman, I found the post where this is mentioned.
a bit further down this is then stated:
Quote
> Der Fehler tritt auch bei größeren Kondensatoren auf - Werte < 0,8 Ohm
> werden als 0.00 Ohm angezeigt - erst darüber sind die Werte mit denen
> der "328er" vergleichbar.

Die Ursache war eine falsche Abfrage in der Funktion GetESR.S speziell für den ATmega644.

So I tested to recompile the latest git version of K-firmware and then the R0 test is fine! (At 8MHz)

So I swapped it for a 16MHz crystal however then the issue with the R0 values being 0.00Ω came back :(
I have spent allot of time looking at the GetESR.S file in K-Firmware because I think the issue is there.
If you look at the value "FAKTOR_ESR" it is defined to 30250 if the processor type is Atmega644.
Otherwise it will be defined as 550000
Then we get to a if statement if the CPU speed is 16MHz
However here all definitions are commented out!
I'm no expert on C code
<cut...>

EDIT: I tried a couple edits of GetESR.S but could not get it right.
Then I found this post linked below by Yuriy_K and his attached HEX file in "Hiland_M644.zip" from post #810901 works great!
I'm unable to compile that version though when using his version of GetESR.S with the latest git release so too much has changed I guess :(
https://vrtp.ru/index.php?showtopic=25020&st=1170#
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 24, 2022, 05:34:35 am
I would be very grateful if you could give some idea where you think the issue is with the K-firmware that I see.
Am I on the right path with trying to adjust "FAKTOR_ESR" or was there some other much more imprtant thing you had to change?
"FAKTOR_ESR" Only works for 20nF - 200nF capacitors. For electrolytic capacitors, I changed a few places. But I consider myself understanding enough in Assembler to lecture Karl-Heinz. Who does not fit my firmware, do not use. I can't help anymore.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ledtester on July 24, 2022, 02:31:27 pm
But anyways we should keep an eye on what the vendors puts on the shelves the next months, so maybe the market could shift in the medium run, we will have to wait.

I concur! For the foreseeable future we'll stay with the ATmega328 and 644 (324, 1284).

I'm curious if there is any interest in porting the TransistorTester code to the STM32 platform?

FNIRSI seems to have done that with their DSO-TC2 product -- a mash-up of the "200 KHz scope" and the transistor tester:

https://www.eevblog.com/forum/testgear/new-(toy)-dsolcr-meter-fnirsi-tc2-(june-2022)/msg4318003/#msg4318003 (https://www.eevblog.com/forum/testgear/new-(toy)-dsolcr-meter-fnirsi-tc2-(june-2022)/msg4318003/#msg4318003)

Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 24, 2022, 02:49:28 pm
Does this justify these measurements with 0805 X5R/X7R?

New parts, I tried to use the shortest lead possible.
All with the same 0.33k \$\Omega\$ ESR.   |O
10uf displays 11.14uf, on keysight multimeter it displays 9.1uf.

Did I get junk parts? Or is the meter crazy?
I will clarify the ESR measurements of ceramic capacitors. Here are the readings of a similar capacitor on the NJ100S - initial and final values. All values on the chart. readings on different devices "k" and "m" firmware ATmega 328 - 644. Readings "k" firmware after warming up for 1-2 minutes drops to a value of 0.05 -> 0.03 \$\Omega\$, readings "m" firmware little depends on warming up. Red arrows indicated the approximate ratio of measurement frequencies.

P.S. Anyone who bought Ttesters on other microprocessors can forget about the shown resolution and accuracy of measuring ESR, small capacitances of capacitors and diodes, etc. All the latest "novelties" of Chinese manufacturers are a pathetic parody for measuring instruments.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 24, 2022, 03:06:13 pm
I'm curious if there is any interest in porting the TransistorTester code to the STM32 platform?

That's one of the commonly asked things. For detecting semiconductors we need 5V (some parts require even more). IIRC, the STM32 family is 5V tolerant, but can't provide 5V without the help of additional circuitry. So we would have to add a switch matrix. And this would make the design more complex and expensive which is detrimental to the design goal of being simple and inexpensive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 24, 2022, 03:43:15 pm
P.S. Anyone who bought Ttesters on other microprocessors can forget about the shown resolution and accuracy of measuring ESR, small capacitances of capacitors and diodes, etc.

That's a good point! Since we have several questions about porting the Transitortester to other MCU families, please let me explain what the main obstacles are. As already mentioned, we need a 5V MCU. Many measurement algorithms are specifically taylored for the ATmega to get the maximum possible, or for precise timing of events. Porting these algorithms to other MCUs will take a lot of time and effort to get it right. The current OSHW firmwares are the result of 10 years' work. So we're hesitant to move to a new MCU family, unless there is a better one to be worth the effort.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 24, 2022, 04:19:45 pm
Many measurement algorithms are specifically taylored for the ATmega to get the maximum possible, or for precise timing of events. Porting these algorithms to other MCUs will take a lot of time and effort to get it right.
I think that a lot depends on the desire and ability of Chinese programmers to bring the sold device to certain standards, to which we are accustomed since the founding of the project. As we have seen on the example of using a platform other than ATMEL AVR, it will not easy to do. For example, the new DSO-TC2 does not measure ESR but only VLoss. But in my opinion it's better than showing "fantastic" results on a LGT328P clone. ;D I have said before that we will get more unpleasant surprises if we test the clones now on the new CPUs in all modes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: edgard22 on July 24, 2022, 11:18:23 pm
Good afternoon, I am an enthusiast of this project, I use the ay-at with Markus 1.47m software and I would like to know if it is possible to add the base-emitter and collector-emitter capacitance to the data shown in the BJT's, since it would be very useful when identify false transistors (something unfortunately more and more frequent and that has already given me several headaches). I use this method with power transistors since it allows to obtain with some precision the size of its silicon chip. Although it is possible to do it by connecting only the aforementioned terminals, I think it would be very useful to see it as data to the already existing ones.
Unfortunately I do not have the knowledge to carry out such a modification and I would appreciate your help to achieve it.
Thank you very much.
ps: Sorry if the words are not well expressed, I'm using a translator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 25, 2022, 02:19:38 am
I use the ay-at with Markus 1.47m software and I would like to know if it is possible to add the base-emitter and collector-emitter capacitance to the data shown in the BJT's
What prevents you from shifting the transistor in the measuring sockets 1112333, as shown in the pictures, or using separate wires?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 25, 2022, 10:36:56 am
Shouldn't the third terminal be grounded? For example, for C_eb (NPN) ground the collector and measure capacitance between emitter and base.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 25, 2022, 02:28:46 pm
Shouldn't the third terminal be grounded? For example, for C_eb (NPN) ground the collector and measure capacitance between emitter and base.
The answer to your question requires some clarification. I found the technique for measuring the capacitances of transitions in the old Soviet GOST. An excerpt with translation and a diagram in the left column, below the readings of a 1000 pF capacitor, on a home-made device that I will use as a "reference".
Further along the columns: Diode 1N4148, capacitance be, capacitance bc.
Comparison of readings "m" and "k" firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 25, 2022, 02:53:26 pm
That's interesting! Infinion's application note AN024 about 'Parasitic Capacitance in Bipolar Junction Transistors' (https://eva.fing.edu.uy/mod/resource/view.php?id=90733) shows different ways (open and shorted) with their specific definitions. Shall we go for the method with the third terminal open or shorted?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 25, 2022, 06:09:24 pm
(https://www.infineon.com/dgdl/AN024.pdf?fileId=db3a30431400ef6801142715ee7106d3 (https://www.infineon.com/dgdl/AN024.pdf?fileId=db3a30431400ef6801142715ee7106d3))
From this link I get:
HTTP Status 404
Type Status Report

Description The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 25, 2022, 06:35:28 pm
Sorry! I've updated the link.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 25, 2022, 07:39:36 pm
I would be very grateful if you could give some idea where you think the issue is with the K-firmware that I see.
Am I on the right path with trying to adjust "FAKTOR_ESR" or was there some other much more imprtant thing you had to change?
"FAKTOR_ESR" Only works for 20nF - 200nF capacitors. For electrolytic capacitors, I changed a few places. But I consider myself understanding enough in Assembler to lecture Karl-Heinz. Who does not fit my firmware, do not use. I can't help anymore.
I can understand that you are tired of me Yuriy_K but I really like your dedication! :)
I used the latest GIT version with only this code replacing line 832 (https://github.com/kubi48/TransistorTester-source/blob/645773139d9b20ede23979dde81b1f735cd3e61c/trunk/GetESR.S#L832):
Code: [Select]
#if (PROCESSOR_TYP == 644) || (PROCESSOR_TYP == 1280)
        #define FULL_PULSE_LENGTH_TICS ((HALF_PULSE_LENGTH_TICS*2) - 1)
#else
#define FULL_PULSE_LENGTH_TICS ((HALF_PULSE_LENGTH_TICS*2)+(MHZ_CPU/14))
#endif
With this change I have the following result:
Code: [Select]
GM328R 20MHz: Hiland644-1*: Hiland644-2*: Hiland644-3*: Hiland644-4*
20mΩ resistor: 0.01Ω 0.00Ω 0.15Ω 0.01Ω 0.03Ω
50mΩ resistor: 0.04Ω 0.03Ω 0.19Ω 0.05Ω 0.06Ω
47nF film cap: 46nF 0.50Ω 46.0nF 0.00Ω 46.1nF 1.10Ω 46.1nF 0.23Ω 47.1nF 12.0Ω
330nF film cap: 319.2nF 0.10Ω 316.7nF 0.00Ω 317.4nF 0.23Ω 316.3nF 0.12Ω 324.7nF 1.74Ω
2200µF lytic (KMG): 2326µF 0.10Ω 2327µF 0.07Ω 2229µF 0.28Ω 2470µF 0.08Ω 2294 0.11Ω
1000µF polymer (PSG): 980µF 0.02Ω 980µF 0.04Ω 942µF 0.13Ω 1044µF 0.05Ω 960µF 0.01Ω
Hiland644-1*= Latest GIT release, no changes (unable to read ESR of small caps).
Hiland644-2*= Latest GIT release, changed GetESR.S according to code above. (reads small caps but with a bit high ESR, same for resistors)
Hiland644-3*= Latest GIT release, same as Hiland644-2 but also changed FAKTOR_ESR on line 578 (https://github.com/kubi48/TransistorTester-source/blob/master/trunk/GetESR.S#L578) to: 550000 (reads pretty good!).
Hiland644-4*= M-firmware 1.48m-beta (added by edit later for comparison).

But I don't understand the purpose of the original code:
Code: [Select]
#define FULL_PULSE_LENGTH_TICS ((HALF_PULSE_LENGTH_TICS*2)+(MHZ_CPU/14))I checked the source and "MHZ_CPU" is defined as the frequency in Hz divided by a million, so it is for example "8" with 8MHz CPU.
"HALF_PULSE_LENGTH_TICS" is defined a very similar way.
What I don't get is why it is then divided by the frequency of the CPU by the number 14?
And in your changed version in my example code above this is instead "-1" if the CPU is Atmega644, but why?
Title: Re: $20 LCR ESR Transistor checker project
Post by: edgard22 on July 25, 2022, 09:21:10 pm
Yes, it is the same to connect only 2 terminals to see the junction capacitance, but sometimes it is inconvenient when there are many transistors. Anyway I copied a few lines of code in the BJT sector and I achieved the task.
In the photos you can see measurements of several 2SC5200 of different qualities. The one that shows Cbe460pF is very bad, measured with another instrument it has a Vbr of 130V (The originals generally measured Vbr above 320V)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 26, 2022, 06:00:14 am
Yes, it is the same to connect only 2 terminals to see the junction capacitance, but sometimes it is inconvenient when there are many transistors. Anyway I copied a few lines of code in the BJT sector and I achieved the task.
Incorrect measurement examples, you cannot compare I_E = 6.25mA readings with I_C = 0.935mA readings. The tester incorrectly detects the emitter and collector pins. From this, the capacity of the transition "eb" is incorrectly determined. Measure on individual wires and see if I'm right.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 26, 2022, 06:20:21 am
I can understand that you are tired of me Yuriy_K but I really like your dedication!
I showed my settings, measurements and firmware with corrections on page 311. I have nothing more to say.
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on July 26, 2022, 09:57:40 am
on 1.45m firmware, on 16M MCU crystal single measurement takes 10..30sec, is it possible to make it faster ?
or leave only R/C/L mode, disable all others to make faster detection
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 26, 2022, 10:00:52 am
on 1.45m firmware, 16M crystal single measurement takes 10..30sec, is it possible to make it faster ?
M-firmware tests crystals only if there is an extended version of the frequency meter! Which version of the clone (device)are you using?
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on July 26, 2022, 10:02:03 am
thats MCU crystal, I measure only R/C/L elements
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 26, 2022, 10:04:48 am
Check if you have programmed the MCU fuses correctly?
H:D9 L:F7 E:FD(FC)
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on July 26, 2022, 10:30:27 am
tried - nothing changed. Measured with frequency counter - 16M generation on crystal is ok

is it possible to disable TP2 probing ?
test clips connected to TP1/TP3, but sometimes it detects component on TP1/TP2
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 26, 2022, 11:31:45 am
is it possible to disable TP2 probing ?
There's no need for that.Read the section in the manual for the tester where it is indicated how to start the self-testing procedure and show us these results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 26, 2022, 01:15:58 pm
Sorry! I've updated the link.
I looked, I re-quote the transistor measurements from the previous page. The unconnected lead lies on top of the case. For the bottom row I will explain by numbers:
1. base and collector are connected together,
2. The сollector lead not connected,
3. The emitter is not connected,
4. The emitter is connected to the collector,
5. The base is not connected.

The examples shown show that not connecting free terminals has little effect on the readings of the capacitances of the junctions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 26, 2022, 01:19:41 pm
on 1.45m firmware, on 16M MCU crystal single measurement takes 10..30sec, is it possible to make it faster ?
or leave only R/C/L mode, disable all others to make faster detection

Are you talking about measuring large capacitors?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 26, 2022, 01:43:02 pm
The examples shown show that not connecting free terminals has little effect on the readings of the capacitances of the junctions.

Thanks for checking! The capacitance between the  terminals is a bit more complex because there a several capacitances adding up. The capacitance of the leads, junction capacitance and diffusion capacitance. The latter two change with bias, frequency, temperature and so on. Anyway, if 'third terminal open' provides a usable value then we can use this method.
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on July 26, 2022, 02:50:10 pm
Quote
Are you talking about measuring large capacitors?
yes

simply shorted pins PC1,PB2,PB3 (TP2) - now measures much faster and no false detections...
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 26, 2022, 03:07:26 pm
simply shorted pins PC1,PB2,PB3 (TP2) - now measures much faster and no false detections...
Nothing is clear from your explanation because you don't state your problem correctly from the start and no name your clone model. There are no psychics here to guess at your measurement difficulties. |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 26, 2022, 05:05:53 pm
Quote
Are you talking about measuring large capacitors?
yes

As larger the capacitance as longer it takes. This is normal for the measurement method used.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 26, 2022, 05:15:25 pm
As larger the capacitance as longer it takes. This is normal for the measurement method used.
Madires,that's right,but not 30 seconds,even if he is it measures 100mF capacitance! :D
Capacity of 10mF is measured by m-firmware with quartz 16MHz for 5-6 seconds, the capacity of 100mF -15 seconds! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on July 26, 2022, 05:31:37 pm
found crack on PC1 trace, so maybe it was catching noise from near tracks.
now all works fast
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 26, 2022, 07:32:46 pm
Glad you found the cause. I can't remember that I ever heard of that issue, i.e. a broken trace causing a delayed probing cycle.
Title: Re: $20 LCR ESR Transistor checker project
Post by: edgard22 on July 26, 2022, 08:50:49 pm
Yes, it is the same to connect only 2 terminals to see the junction capacitance, but sometimes it is inconvenient when there are many transistors. Anyway I copied a few lines of code in the BJT sector and I achieved the task.
Incorrect measurement examples, you cannot compare I_E = 6.25mA readings with I_C = 0.935mA readings. The tester incorrectly detects the emitter and collector pins. From this, the capacity of the transition "eb" is incorrectly determined. Measure on individual wires and see if I'm right.
You are right, but the values ​​read with the multimeter, although they differ a little from the AY-AT, maintain a relationship. I believe that an exact value is not necessary since it is used as a reference and it is possible to clearly differentiate them in a primary classification.
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on July 27, 2022, 07:49:07 am
Glad you found the cause. I can't remember that I ever heard of that issue, i.e. a broken trace causing a delayed probing cycle.
is it possible to increase parameters indication time, before next measurement ?

small 128x32 0.91" OLEDs are supported, or only 128x64 ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on July 27, 2022, 08:34:06 am
is it possible to increase parameters indication time, before next measurement ?

You can change it here in config.h:
Code: [Select]
/*
 *  Maximum time to wait after probing (in ms).
 *  - applies to continuous mode only
 *  - Time between printing the result and starting a new probing cycle.
 */

#define CYCLE_DELAY      5000

But you can also instead enable this and the tester will wait for button or encoder input to measure again:
Code: [Select]
/*
 *  Set the default operation mode to auto-hold.
 *  - instead of continous mode
 *  - uncomment to enable
 */

#define UI_AUTOHOLD
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 27, 2022, 08:48:31 am
... or you can start the tester with a long button press (>300ms) to enter the auto-hold mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 28, 2022, 05:23:19 pm
madires
I will try to explain the identified problem in main.c. When checking on the "m" firmware of the specified transistor, in my opinion, a very important parameter Vbe was missing. The given corrections allow to show this value. I understand that my solution looks primitive. I hope you find a better solution...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 28, 2022, 06:28:40 pm
In this case it's not a bug, it's a feature. Any base-emitter resistor(s) will screw up some measurements and make related results less meaningful. When no base-emitter diode (or two in series for a Darlington) is found V_BE and h_FE aren't displayed. For measuring the h_FE of a power BJT a higher base current would be helpful. The tester can provide just 7mA which isn't sufficient for this. So a simple trick is used to extrapolate mathematically a higher base current. This doesn't work for a power BJT with base-emitter resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: n6rob on August 03, 2022, 11:19:32 pm
Greetings;

I have a LCR-T4 (mega328p, 8 MHz crystal, 78L05, TL431, one button, no encoder, no up/down buttons) and I have loaded 1.47m on it successfully (also previously loaded 1.13k, but that's another story).  Anyhow, running 1.47m, and noticing some odd behaviors.

Here's what I did; per instructions I edited Makefile, config.h, and config_328.h with appropriate settings (as best I could).  If I was unsure about a software or hardware feature, then I took it out.  The unit boots, and displays fine (had to flip the display and remove the offset in the x axis of the display), and responds to the button as expected.

Observations:
The unit boots, and runs a test and comes back with an IGBT N-ch (with nothing in the test port).
I put the unit in menu mode by quickly clicking twice, I select test, it asks for a short, I install it, and then it does nothing.  I quick-click, and it returns the menu (if I long-click then it gives an error! and returns to the menu).
If I leave the short in during a normal test cycle, it says "probing..... C", it takes a while, but then shows the short across all three terminals.  (Draws a fair bit of current, about 45 mA, from the power supply, too).
It reads an resistor, LED, or an NPN, or a PNP, as an IGBT.
It reads a resistor as "no component found".

Measuring resistance (power and ISP programmer disconnected) between test pins 1 and 2, I get 39K ohms, from 2 to 3 I get an open, from 1 to 3 I measure about 1.4M ohms.  I'm going to hit Google and look for a schematic for this unit after I post this.

Any suggestions of things I should look for?  Much appreciated.

Rob

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 04, 2022, 10:19:11 am
Have you used the settings listed in the Clones file? There could be something wrong with the pin assignments for the probes. You'll find a schematic at https://disk.yandex.ru/d/yW8xa5NJgUo5z (the T4 comes in two variants).
Title: Re: $20 LCR ESR Transistor checker project
Post by: n6rob on August 04, 2022, 05:54:05 pm
Have you used the settings listed in the Clones file? There could be something wrong with the pin assignments for the probes. You'll find a schematic at https://disk.yandex.ru/d/yW8xa5NJgUo5z (the T4 comes in two variants).

Greetings and thank you for your reply.

Yes, I referenced the Clones file when updating the configuration files.
Thanks for the link to the reference files, including schematics.  In reviewing the photos I can say that I have the T4/T3-NoStripGrid version.  That helps.  I just referenced the schematics and the pin designations in the config_328p.h file and I don't see any incorrect assignments.

Since my last post, I have reloaded the original firmware (as it came when I bought it, "MTester", no version indicated).  It exhibits some of the same problems.  I might play with the 1.13k version again (previous attempts have given the same results as the original & 1.47m firmware).

Taking a step back, I think it is likely that I have damaged something at the test ports (probably the chip).  I probably failed to discharge a cap before testing; but that is just a guess.

The next step I'll take is to disassemble the unit from the case and inspect it for damaged traces, solder bridges, or cracked solder joints.  It worked just fine for a few years; this weird behavior is more recent.
 If I learn something new, I will post back here.  Otherwise, I would consider this a case of damaged hardware.

Thanks for the help.

Rob
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 04, 2022, 06:33:19 pm
Then it's most likely caused by damaged I/O pins. To verify this you can run the self test and look for strange values (or post them here).
Title: Re: $20 LCR ESR Transistor checker project
Post by: n6rob on August 04, 2022, 07:01:01 pm
Then it's most likely caused by damaged I/O pins. To verify this you can run the self test and look for strange values (or post them here).

I de-fluxed the board, cleaned-up a few things, looked for cracks, shorts, etc.  I didn't find a smoking-gun.

I entered menu mode, select "test", it asks for a short, I install the short, and then nothing happens.  I wait a minute, click the button, and it goes back to the main menu.
I entered the menu mode, select "adjustment", and get the same result as "test".

I entered "show values" I find the following:
Ri- 20 ohms
Ri+ 22 ohms
C0 43 pF
R0 0.2 ohms
Vref 1084 mV
Vcc 5049 mV *
Acomp 0 mV
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 04, 2022, 07:26:41 pm
I see. In this case replace the ATmega or get a new tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: blubillcanada on August 05, 2022, 02:54:02 pm
I wonder how hard this project would be to port over to a Raspberry Pi Pico.
USB would make for a simple display on a PC to keep it real simple, also firmware updates would be a snap.
A significant increase in the program memory 2MB vs 32kB, more speed! & cheap too.
It can be programmed in C++ or Python
The ADC VREF is easy, LM4040 is recommended in the Pico datasheet.
pushbutton(s), 470K,  680ohm resistors and a connector would be all the external parts for a basic unit.
Optionally:
The original tester schematic just for reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 05, 2022, 03:23:19 pm
That was answered already just two pages back: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4318561/#msg4318561 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4318561/#msg4318561)
The Raspberry Pi Pico has the same drawback, it runs with 3.3V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: n6rob on August 08, 2022, 08:11:32 pm
I have no idea what version that is, but trying a OCR translation it seems to be saying that the USB port is only for user upgrades (of the firmware) and that it does not supply power.

Then it should be possible to update the firmware directly via avrdude.

Do you have any suggestions for how to set avrdude (in Linux command line)?  I'm not sure how to set the "-c" switch (i.e. which programmer) as I am connecting my computer USB directly to the USBC connector on the board.

~$ lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 046d:c534 Logitech, Inc. Unifying Receiver
Bus 001 Device 019: ID 1a86:7523 QinHeng Electronics CH340 serial converter
Bus 001 Device 002: ID 05e3:0608 Genesys Logic, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

I tried this...

~$ avrdude -c ttl232r -p m328p
avrdude: ft245r_open(): invalid device identifier '        '

avrdude done.  Thank you.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 09, 2022, 09:40:31 am
Adding the port argument might help, e.g. -P /dev/ttyACM0. But I don't know which programmer needs to be set for the CH340.
Title: Re: $20 LCR ESR Transistor checker project
Post by: n6rob on August 09, 2022, 04:48:13 pm
Adding the port argument might help, e.g. -P /dev/ttyACM0. But I don't know which programmer needs to be set for the CH340.

Okay.  I played around with a few port designations and programmer options but was never successful. 

I wrote to the seller asking for instructions and a schematic.  They replied and said they were working on getting me the info.  If I learn anything I will share it here.

Thanks for the help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on August 15, 2022, 09:42:56 am
Hello everyone.
I like to try out the different options Madires adds to our little meter.
The last thing was the continuity meter that is already working thanks to the help of Indman.

Now I have assembled the circuit for the LOPT/FBT measurement but it does not work.
I have reviewed the assembled circuit and in principle it is fine, but it does not go beyond screen 1, both with or without the coil being tested.
It always emits a small constant and intermittent sound.

Perhaps, as in the case of continuity, some other adjustment must be made or activated.
Please if someone can help me to solve the problem.

Thank you

(https://i.ibb.co/JpwWJhY/2022-08-15-11-22-23.png) (https://ibb.co/JpwWJhY)  (https://i.ibb.co/ctz9fYz/2022-08-15-11-23-28.png) (https://ibb.co/ctz9fYz)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 15, 2022, 10:17:50 am
Could you please post your settings for the ring tester? Do you have a scope to check the trigger pulse and the rings?
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on August 15, 2022, 04:25:29 pm
Could you please post your settings for the ring tester? Do you have a scope to check the trigger pulse and the rings?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 15, 2022, 05:47:40 pm
And the settings for RINGTESTER_PORT, RINGTESTER_DDR and RINGTESTER_OUT? Is the port pin set in RINGTESTER_OUT used by any other setting too?
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on August 15, 2022, 06:26:58 pm
The three that you tell me are activated

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 15, 2022, 07:14:49 pm
You have
 #define RINGTESTER_OUT   PD5       /* pulse output */
and
 #define BUZZER_CTRL      PD5       /* control pin (low: off / high: on) */
while
 #define HW_RING_TESTER
and
 #define HW_BUZZER

So ring tester and buzzer are enabled and are using the same port pin. Try another pin or disable the buzzer (also remove the buzzer).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on August 16, 2022, 06:41:49 am
Information for users of my firmware. The reaction to a short-circuited coil is shown in the pictures on the right.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 16, 2022, 08:00:25 am
The reaction to a short-circuited coil is shown in the pictures on the right.
This method does not guarantee 100% detection of short-circuited coil.Example in the photo below. You should always have a sample of a similar, serviceable throttle to compare readings. The simplified version of LOPT/FBT also cannot guarantee accurate detection of short-circuited turns and is very dependent on the core material. It is better to use specialized devices for this purpose. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: masster on August 21, 2022, 03:56:13 am
Does anyone have the schematic for the tester clone known as Kuman Multifunction Transistor Checker or DROK Transistor tester?
https://www.amazon.com/kuman-Multifunction-Transistor-Automatic-Identification/dp/B075DDXV11 (https://www.amazon.com/kuman-Multifunction-Transistor-Automatic-Identification/dp/B075DDXV11)
http://www.kumantech.com/kuman-multifunction-transistor-tester-with-18-inch-lcd-tft-display-mega328-npn-pnp-automatic-identification-transistor-diodes-dual-diode-scr-res_p0435.html (http://www.kumantech.com/kuman-multifunction-transistor-tester-with-18-inch-lcd-tft-display-mega328-npn-pnp-automatic-identification-transistor-diodes-dual-diode-scr-res_p0435.html)

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 21, 2022, 06:53:56 am
masster Look at my resource https://disk.yandex.ru/d/yW8xa5NJgUo5z the "Fish8840TFT" folder
Title: Re: $20 LCR ESR Transistor checker project
Post by: firewalker on August 21, 2022, 08:20:10 am
masster Look at my resource https://disk.yandex.ru/d/yW8xa5NJgUo5z the "Fish8840TFT" folder

The folder with the MK-328 is the firmware the device came with?

Alexander.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 21, 2022, 09:06:56 am
firewalker No, if there is a factory firmware, it will be located in the "Firmware/Original" folder

Hi,
I know there are a lot of different models, anyway have you saw this one ?
What is the purpose of USB interface ?
I try to use it to supply the module, it shows around 7 V, but didn't measure a simple resistor.
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4291063/#msg4291063 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4291063/#msg4291063)

Surprises from Chinese friends continue! ;D
This clone of T4 is not based on the original ATmega328, but so far on a processor known only to FNIRSI.
The marking on the ATMega328PU-TH case is a fake, since the pins of this chip does not match either ATMel or LGT8F328P.
The K2 button is used to enter BootLoader mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: masster on August 21, 2022, 10:10:57 am
Quote from: indman on Yesterday at 11:53:56 pm (https://www.eevblog.com/forum/index.php?topic=14399.msg4370932#msg4370932)>masster Look at my resource https://disk.yandex.ru/d/yW8xa5NJgUo5z (https://disk.yandex.ru/d/yW8xa5NJgUo5z) the "Fish8840TFT" folder

Quite a treasure you have there. Well organized and very full of resources.

Just a short observation though. On the schematic it is missing the LED between R6 and Q3.


I am confronting myself with the following problem: while the tester is working fine, when I press the TEST button, the current consumption is 220 mA (!!) and the battery voltage is reported wrong (7.72V instead of 8.9V). Transistor Q1 gets very hot. Alcohol evaporates almost instantly on it, in comparison with the other components. If I supply 6V instead of 9V, the current consumption drops to about 70mA, still too much IMO. Could it be a faulty capacitor C1?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 21, 2022, 10:54:15 am
Just a short observation though. On the schematic it is missing the LED between R6 and Q3.
Yes, thank you, I will supplement the scheme with this missing element, which plays an important role in the scheme.

I am confronting myself with the following problem: while the tester is working fine, when I press the TEST button, the current consumption is 220 mA (!!) and the battery voltage is reported wrong (7.72V instead of 8.9V). Transistor Q1 gets very hot. Alcohol evaporates almost instantly on it, in comparison with the other components. If I supply 6V instead of 9V, the current consumption drops to about 70mA, still too much IMO. Could it be a faulty capacitor C1?

This is already a known unpleasant problem for this clone. Look carefully at the picture I attached below and everything will become clear to you. Instead of a 3.3V Zener, a 3.3 volt stabilizer should be installed in the sot-23 to power the TFT screen, and the board is divorced incorrectly.2 and 3 outputs shorts are connected on the board. Drawn in red. Tracks need to be cut. In fact, there is a zener diode directly parallel to the output of the 7805. VCC instead of five sinks to 4 volts, and wild consumption from the battery. In the absence of stabilizers in sot-23, I put 1117-3.3 in sot-223, it is better to leave the resistor in front of the TFT screen at one 100 ohms, but you only need to solder it from the seat, it goes straight to 5 volts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: masster on August 21, 2022, 11:50:16 am
@indman
1) Is the schematic attached the correct one? I mean, having all the corrections already applied?
2) Resistors R3 and R5 are 33K. Shouldn't be R3=10K and R5=3K3 to show the correct value of the battery voltage?
3) I have attached a high resolution photo of my board. Can you draw on it again, please? Because the other photo is low resolution, and I can't see exactly what to cut and what to connect.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 21, 2022, 01:18:05 pm
1. Yes, the scheme is correct.
2. You can change the resistors R3-R5 if you want to use new k and m-firmware. Or compile the firmware for the divider 33k/33k yourself.
3. I showed in the photo which jumper should be removed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: free_electron on August 23, 2022, 03:41:01 am
has anyone ported this to a 329 or 629 ? how much code would need to change ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 23, 2022, 08:38:46 am
I'm not aware of anyone. No idea! If the 329 is basically a 328 plus additional features, then it should be just some minor adaptions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on August 23, 2022, 11:47:22 am
Appart from being on a 64pin case, the main features of the 329pa look similar to those of 328pb. Attached a quick comparison.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jacon on August 23, 2022, 11:53:15 am
... a 328 plus additional features...
329 seems to have additional LCD controller only...
Title: Re: $20 LCR ESR Transistor checker project
Post by: masster on August 25, 2022, 04:01:43 am
Quote from: indman on August 21, 2022, 06:18:05 am (https://www.eevblog.com/forum/index.php?topic=14399.msg4371511#msg4371511)
1. Yes, the scheme is correct.
2. You can change the resistors R3-R5 if you want to use new k and m-firmware. Or compile the firmware for the divider 33k/33k yourself.
3. I showed in the photo which jumper should be removed.

>@indman

It would help a lot for future owners of Fish-8840TFT to find in Clone Tester folder on YandDisk a detailed description of the modifications they have to make. In my opinion, the easiest to understand would be to draw 2 schematics. One schematic should show the original WRONG tracks and components (from factory) and another schematic the CORRECT ones.

Thank you for everything.
Title: Re: $20 LCR ESR Transistor checker project
Post by: free_electron on August 26, 2022, 01:23:47 am
does anyone have this thing available as a Atmel studio 7 project ?

i got as far as getting the gcc compiler installed and make and got it to build.
then i installed atmel studio 7. now make under the command prompt no longer works . it throws an error " the system cannot find the path specified".
Everything worked fine until installed studio 7.

i can also not import the makefile into studio 7 using the makefile import tool. it keeps complaining the makefile is not correct.

i'm getting frustrated ... why is this stuff always so bloody complicated.

or is there an other ide with the abilities of visual studio to edit this project ? if so : how to install it and load this as a project ?

thanks

more info :
if i run make on a freshly unzipped tarball it works fine.
if i re-run make without doing anything else i get the "the system cannot find the path specified" error

c:\comptester\make <enter>
..... compiles complete and produces output
c:\comptester\make <enter>
The system cannot find the path specified -barf-


-edit 2-
offending line is 221 : -include $(shell mkdir dep 2>/dev/null ....
i commented it out.

now i can import in studio 7 and the build works there too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on August 26, 2022, 11:34:18 pm
Let's say we received a new Chinese T7 clone, a TQFP32 MCU without any marks @16MHz. Is there any way to make an educated guess on what knock-off it can be, LGT8F328P or other?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 27, 2022, 06:24:34 am
Feliciano,this is not difficult to do. ATmega and LGT8F have detailed documentation.It is enough to look closely at the location of Vcc and GND to determine the processor family.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on August 27, 2022, 09:20:43 am
What is  the best transistor tester to buy?

Not really interested in hacking it, just in getting the more advanced one of the many options available in the web.

Thanks a lot in advance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: amershehzadawan on August 27, 2022, 11:52:34 am
Hi everyone

first of all i really admire this great project. i salute all developrs of this project.

i am writing this after reading numerous posts in eevblog.com and mikrocontroller.net as well Transistortester documentation and source files at github repository and various firmware files at Yandex drive.

As this project progresses and so far no commercial transistor testor includes new features like continuity tester or ring tester. So i decided to make this testor on Atmega2560. But this chip (and others 644/1280) are not available in my country and Atmega328 has shorter flash memory and so forth i am only left to arduino version of Atmega2560.

The github repository includes Arduino Mega2560 'hex' and 'eeprom' files of newly released version 1.47m and also the source files.
I understood the software options required to be set in config.h or makefile etc.

My questions are

1 What are the hardware changes required for version 1.47m to be make to the arduino mega board to make this testor workable, apart from required 0.1 resistors etc and shorting of two pins to make frequency generator work. Do we have a schematic which includes continuity with buzzer option, zener testor, ring testor etc.
2 How to flash eeprom file to arduino mega.

If someone has already made some progress towards making this testor on arduino Mega2560 please share with me. It would be very helpful.
i know a version 1.13k that has made by plouc68000 two years back. But that does not include newly included fantastic options. And i am unable to translate '.c' to '.ino' files like he did.

your help will make my day

Thanks and regards,
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 27, 2022, 02:28:57 pm
What is  the best transistor tester to buy?

Not really interested in hacking it, just in getting the more advanced one of the many options available in the web.

Please see https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 27, 2022, 02:40:32 pm
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4291063/#msg4291063 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4291063/#msg4291063)
This clone of T4 is not based on the original ATmega328, but so far on a processor known only to FNIRSI.
The marking on the ATMega328PU-TH case is a fake
Attention! Check with the seller which version of LCR-T4 he will send you, because updating the firmware and upgrading(repair) it is not yet possible! If this is important to you, then this version of the clone has a Chinese APT32F172K8T6 processor installed  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 27, 2022, 02:49:51 pm
1 What are the hardware changes required for version 1.47m to be make to the arduino mega board to make this testor workable, apart from required 0.1 resistors etc and shorting of two pins to make frequency generator work. Do we have a schematic which includes continuity with buzzer option, zener testor, ring testor etc.

We don't have a reference schematic for ATmega2560, but it's fairly simple to add the hardware options. Have you seen the required settings for Arduino in the Clones file and the default pin assignments in config_1280.h?

2 How to flash eeprom file to arduino mega.

Via avrdude for example (either directly via the ISP header, or when the Arduino bootloader is flashed via the USB2serial onboard adapter).

If someone has already made some progress towards making this testor on arduino Mega2560 please share with me. It would be very helpful.
i know a version 1.13k that has made by plouc68000 two years back. But that does not include newly included fantastic options. And i am unable to translate '.c' to '.ino' files like he did.

I've tested the m-firmware on a Mega2560 clone and it works fine. Ports for Arduino use the Arduino HAL which takes away some ressources and therefore limits what is possible, i.e. some features aren't available.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on August 27, 2022, 05:47:15 pm
What is  the best transistor tester to buy?

Not really interested in hacking it, just in getting the more advanced one of the many options available in the web.

Please see https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf!

Thanks, mate!
Title: Re: $20 LCR ESR Transistor checker project
Post by: amershehzadawan on August 27, 2022, 07:50:17 pm
Thankyou MADIRES for your prompt reply.

i will check and reply.



Greetings
Title: Re: $20 LCR ESR Transistor checker project
Post by: masster on September 03, 2022, 06:58:32 pm
Quote from: amershehzadawan on August 27, 2022, 04:52:34 am (https://www.eevblog.com/forum/index.php?topic=14399.msg4383688#msg4383688)
My questions are

1 What are the hardware changes required for version 1.47m to be make to the arduino mega board to make this testor workable, apart from required 0.1 resistors etc and shorting of two pins to make frequency generator work. Do we have a schematic which includes continuity with buzzer option, zener testor, ring testor etc.
2 How to flash eeprom file to arduino mega.

>https://www.youtube.com/watch?v=P5zWMnvjfM4 (https://www.youtube.com/watch?v=P5zWMnvjfM4)

https://www.youtube.com/watch?v=NXwT7NL4PQM (https://www.youtube.com/watch?v=NXwT7NL4PQM)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on September 04, 2022, 11:08:59 am
Then it's most likely caused by damaged I/O pins. To verify this you can run the self test and look for strange values (or post them here).

I de-fluxed the board, cleaned-up a few things, looked for cracks, shorts, etc.  I didn't find a smoking-gun.

I entered menu mode, select "test", it asks for a short, I install the short, and then nothing happens.  I wait a minute, click the button, and it goes back to the main menu.
I entered the menu mode, select "adjustment", and get the same result as "test".

I entered "show values" I find the following:
Ri- 20 ohms
Ri+ 22 ohms
C0 43 pF
R0 0.2 ohms
Vref 1084 mV
Vcc 5049 mV *
Acomp 0 mV

I had the exact same problem, I changed the AtMega328p and it came back to normal. The AtMega was damaged.
Title: Re: $20 LCR ESR Transistor checker project
Post by: masster on September 04, 2022, 03:55:53 pm
@indman
Here is the schematic for Fish-8840TFT updated with the original, wrong circuit schematic for 3.3V.
By the way, the current consumption dropped from 180mA to 26mA after correction.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 04, 2022, 04:14:49 pm
@indman
Here is the schematic for Fish-8840TFT updated with the original, wrong circuit schematic for 3.3V.
There are several variants of the Chinese clone Fish8840TFT - on a blue and green printed circuit board. The option on the green board does not have the same error as on the blue one.Therefore, the correct schematic diagram is on my resource. And I gave you the error variant above in the message #7850. This is a child's mistake, which can be easily detected by any amateur radio operator with experience. If he can't fix such a simple mistake, then the question is why does he need this device? ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Substance on September 05, 2022, 12:11:40 pm
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4291063/#msg4291063 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4291063/#msg4291063)
This clone of T4 is not based on the original ATmega328, but so far on a processor known only to FNIRSI.
The marking on the ATMega328PU-TH case is a fake
Attention! Check with the seller which version of LCR-T4 he will send you, because updating the firmware and upgrading(repair) it is not yet possible! If this is important to you, then this version of the clone has a Chinese APT32F172K8T6 processor installed  ;)
Thank you for this information. How did you find out that it has an APT32F172K8T6 microcontroller? I recently bought an LCR-T4 and, unfortunately, I received the "V4.1.3_2022/5/18" hardware version of this tester. I immediately saw something unusual about the microcontroller, and I checked how the (+5V) supply connects to the MCU: GND to pin 18 and VDD to pin 19!

No, this cannot be an Atmel ATmega328P, and the supply pins do match the APT32F172K8T6 pinout! Device marking: it does have an Atmel logo (that looks a bit weird), and "MEGA328P / U-TH / 35473D / 220642H" printed/etched on it. No 8 MHz crystal is mounted, and judging from the empty footprints there is a beginning of a serial-to-USB interface (for a CH340N) on the PCB. (I have seen pictures of this PCB version with the CH340N and USB connector mounted.)

Yes, be careful when ordering a new LCR-T4. If you are expecting to receive a component tester that has a genuine Atmel ATmega328P (which you could then reprogram... ) then a little chat with the seller is recommended. However, resellers may not be aware of this fake clone, or resellers may not be interested in customers demanding a product that has genuine components. My seller stated that the reason for this LCR-T4 having different components (with fake device marking on the MCU) is a "chip upgrade", and no comments on the microcontroller device markings.

So, if you have a chance to see the LCR-T4 before purchasing, it is advised to check the bottom side of the PCB to verify whether there is a crystal present. Also the top side of the "V4.1.3_2022/5/18" version PCB has a distinct pattern of traces running straight from ZIF socket to the 1, 2, & 3 test pads. Many customers have bought this product without knowing or complaining about the MCU. Some customers ask (themselves) what this USB connector is all about, but most customers just report that the device is working fine. I just wanted an LCR-T4 to experiment with and to reprogram it, but I now have to search for an original LCR-T4 clone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 05, 2022, 12:28:00 pm
I just wanted an LCR-T4 to experiment with and to reprogram it, but I now have to search for an original LCR-T4 clone.
Over time, the old LCR-T4 clone will become more and more difficult to obtain, because the deficit and serious rise in price of genuine ATMEL chips will port the author's code to other platforms, which are provided by cheap Chinese CPU variants.
But since the firmware for these processors will not be available yet, consider that you are buying a disposable device. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 12, 2022, 08:40:26 pm
Hi,

I have upgraded my AY-AT to 1.47m. But the encoder does not work. I don't see where is my mistake.



CONFIG.h

#define HW_ENCODER
#define ENCODER_PULSES   4
#define ENCODER_STEPS    20




CONFIG328.h
/*
 *  rotary encoder
 */

#define ENCODER_PORT     PORTD     /* port data register */
#define ENCODER_DDR      DDRD      /* port data direction register */
#define ENCODER_PIN      PIND      /* port input pins register */
#define ENCODER_A        PD3       /* rotary encoder A signal */
#define ENCODER_B        PD1       /* rotary encoder B signal */



Thank for your help
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 13, 2022, 10:34:58 am
The settings look fine. Please open ComponentTester.lss in a text editor and check if function ReadEncoder() is included.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Andbro on September 13, 2022, 11:33:44 am
 
Hi,

This is the part where it talk about the rotary encoder in ComponentTester.iSS

 /*
       *  rotary encoder
       */

      #ifdef HW_ENCODER
      Test = ReadEncoder();        /* read rotary encoder */
    208c:   0e 94 31 0f    call   0x1e62   ; 0x1e62 <ReadEncoder>

      if (Test)                    /* got user input */
    2090:   88 23          and   r24, r24
    2092:   51 f1          breq   .+84        ; 0x20e8 <TestKey+0x14c>
      {
        if (Steps == 0)            /* first step */
    2094:   dd 20          and   r13, r13
    2096:   19 f0          breq   .+6         ; 0x209e <TestKey+0x102>
        {
          Key = Test;              /* save direction */
        }

        if (Test == Key)           /* step in same direction */
    2098:   8d 17          cp   r24, r29
    209a:   11 f0          breq   .+4         ; 0x20a0 <TestKey+0x104>
    209c:   69 c0          rjmp   .+210       ; 0x2170 <TestKey+0x1d4>
    209e:   d8 2f          mov   r29, r24
        {
          Steps++;                 /* increase counter */
    20a0:   d3 94          inc   r13


thank
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 13, 2022, 01:46:52 pm
That means that the firmware included the code for the rotary encoder. If the pin assingnment is correct then maybe it's a hardware problem? Does the encoder still work with the old firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: bffargo on September 17, 2022, 09:24:47 pm
After the appearance of the rounded GM328A, it looks like another new clone has appeared based on a new chip or so they claim. It's called the LCR-T4-TINY and claims to "Using a new generation of chips, more powerful"  :blah:

Even smaller monochrome screen, but now only 4 socket pins doubled up through a .100 female header, and no ZIF for better tight connections.  :--  But it is small, I'll give it that.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on September 18, 2022, 12:39:52 am
Interesting recent posts about this subject, because there are news stating the chips shortage/backlog is starting to slowly decrease.

But anyways we all know the Asian vendors will keep porsuing for cost savings and/or cutting corners. And some people think "the last version should be a better version", and the sellers know it. So we'll have to wait and see...

In the meantime, those among us looking for the ATmega-based units would have to search for older stocks and keep the fingers crossed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on September 18, 2022, 06:36:49 am
amazing why there are no tweezers form-factor for SMD parts in mass-production:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 18, 2022, 11:27:10 am
Nice job! BTW, we have a thread for your creative output: https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/ (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/).
Title: Re: $20 LCR ESR Transistor checker project
Post by: pizzigri on September 22, 2022, 09:26:46 am

Thank you for this information. How did you find out that it has an APT32F172K8T6 microcontroller? I recently bought an LCR-T4 and, unfortunately, I received the "V4.1.3_2022/5/18" hardware version of this tester. I immediately saw something unusual about the microcontroller, and I checked how the (+5V) supply connects to the MCU: GND to pin 18 and VDD to pin 19!

No, this cannot be an Atmel ATmega328P, and the supply pins do match the APT32F172K8T6 pinout! Device marking: it does have an Atmel logo (that looks a bit weird), and "MEGA328P / U-TH / 35473D / 220642H" printed/etched on it. No 8 MHz crystal is mounted, and judging from the empty footprints there is a beginning of a serial-to-USB interface (for a CH340N) on the PCB. (I have seen pictures of this PCB version with the CH340N and USB connector mounted.)

Yes, be careful when ordering a new LCR-T4. If you are expecting to receive a component tester that has a genuine Atmel ATmega328P (which you could then reprogram... ) then a little chat with the seller is recommended. However, resellers may not be aware of this fake clone, or resellers may not be interested in customers demanding a product that has genuine components. My seller stated that the reason for this LCR-T4 having different components (with fake device marking on the MCU) is a "chip upgrade", and no comments on the microcontroller device markings.

So, if you have a chance to see the LCR-T4 before purchasing, it is advised to check the bottom side of the PCB to verify whether there is a crystal present. Also the top side of the "V4.1.3_2022/5/18" version PCB has a distinct pattern of traces running straight from ZIF socket to the 1, 2, & 3 test pads. Many customers have bought this product without knowing or complaining about the MCU. Some customers ask (themselves) what this USB connector is all about, but most customers just report that the device is working fine. I just wanted an LCR-T4 to experiment with and to reprogram it, but I now have to search for an original LCR-T4 clone.

Yeah, well, I got a T7 and it also has the SAME chip in it, with Atmel markings  identical to the last digit. Only silver lining, I paid 13 Euro for it, so it was not a huge loss; and maybe I can recycle some component (namely, LiIon battery, lcd screen, case)...

ETA: and I forgot to say that performance is worse - not hugely, but noticeably - to the other "antique" versions of the tester I already have, all based on the 328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on September 22, 2022, 10:43:40 am
Quote
performance is worse - not hugely, but noticeably
5% resistors, plus high parasitic capacitance in ground-flooded areas
Title: Re: $20 LCR ESR Transistor checker project
Post by: pizzigri on September 22, 2022, 02:32:12 pm
Hi guys,
I've been looking for a Hiland M644 everywhere for some time - including here, with a post on the Buy/Sell/Wanted board.
On aliexpress the Hiland when available goes for almost 40 euro, with the risk that what is received is not at all what it's advertised. Having already lost 35 Euro, including the 13 Euro to the last T7 debacle, the whole point of "cheap" is moot - now it is actually preferable to spend 50-60 Euro in parts and a JLCPCB sourced board to be at least able to have a perfectly working higher end device, rather than throwing literally away money out the window... like i just did with the two dud testers I got chasing the white herring of a M644.
At this point, the option of actually drafting on diptrace a PCB becomes a sort of necessity if I want a real, certified Atmega644 inside.

.... Problem is I tried to search info on the Atmega644 based transistor tester and there is LOTS. In reality, even overwhelming.
Karl-Heinz's 1.13K manual covers a Atmega644 schematic, with many add-ons, including a relay based protection - But, no definite PCB design.
In the repository, the only PCB available is a discrete, thru hole developer kit design without LCD, built around the DIP version of the MCU - and I have a few M644 but in the smt TQFP 44 package.

The most approachable and sensible thing to do could be to use as a basis the Hiland TT-M644 schematic, and either try to loosely redraft (reverse engineer) the PCB following the pictures posted, or try to design a completely new layout...
I can do the grunt work - I can use Diptrace, but a few things are a bit out of my league. Can anyone help me, at least providing an updated schematic based on the Hiland M644 that includes all improvements and corrections discussed here since the introduction of the Hiland a few years back (including the apparently missing Measuring ports protection), and maybe once I manage to actually produce something, check on the drafted design I did not do noob errors?
Once I have a definite design, I will make both diptrace and gerber files available to everyone here! It could become sort of a "reference" design.
Please help...
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 22, 2022, 02:53:00 pm
Karl-Heinz's 1.13K manual covers a Atmega644 schematic, with many add-ons, including a relay based protection - But, no definite PCB design.
Please help...
In fact, this work has already been implemented for you by the author of the extended ATmega644-1284 tester scheme - dear Nick Lanchak. It is his great contribution to the development of this project that Karl-Heinz mentions in his manual.You can read the full documentation on his device here ;)
https://drive.google.com/folderview?id=0B4yqyYy2Daakfl9DeTBkMEJVTVNwajkzNGtjVi0wcjdMUG5ZODJXa216WFZEZG1ZZE1ud3M&usp=sharing&tid=0B4yqyYy2DaakZzBVU3JDSXB6S1E (https://drive.google.com/folderview?id=0B4yqyYy2Daakfl9DeTBkMEJVTVNwajkzNGtjVi0wcjdMUG5ZODJXa216WFZEZG1ZZE1ud3M&usp=sharing&tid=0B4yqyYy2DaakZzBVU3JDSXB6S1E)
Alternative link
http://vrtp.ru/screenshots/3588_Rev_A0.02C_m1284.zip (http://vrtp.ru/screenshots/3588_Rev_A0.02C_m1284.zip)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pizzigri on September 22, 2022, 03:28:58 pm
OK. So, that's FANTASTIC.
In a way, I was aware that someone called NickL. did something - I read the whole mikrocontroller.net/topic/transistortester-avr thread...  But, I could never get access - and as a matter of fact, cannot open the link even now. I login my Gmail but it says I need to request access...
ETA and now, I also tried to ask for access. using the Google form.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 22, 2022, 04:23:00 pm
New modification English k-firmware for GM328A(AY-AT) based on the current 899th revision 1.13K.Quartz 8 or 16 MHz.Font 8x15.

The author's code has been supplemented and corrected in many places to speed up the work and best display the test results:
1. Improved font 8x15, added new symbols of inductance,zener diode,triac,thyristor, "eta" as well as large symbols UJT and PUT.
2. Test results (value data) are highlighted in a separate color.
3. A full pinout for 3 contact parts is always placed at the bottom of the display for convenience when sorting.
4. A new color icon has been added to assess the battery status. If an external power supply(>10V) is used, the display shows the inscription "DCPwr".
5. A small (simple) modification of the circuit allows you to measure the zener diodes at the terminals of the voltmeter "GND" - "V+" up to the voltage of the power supply (9-15V) by holding the Test button for a long time at start. The zener diode symbol will appear on the display if it is connected correctly, and on the 2nd line its breakdown voltage is Vz. If the zener diode is connected as a diode, only the forward voltage drop on it will be displayed on the display Vext.
6. Improved auto-detection of UJT and fixed the display of the transmission coefficient "eta".
7. The tester's algorithm has been changed for cyclic modes [RL] and [C] - now exit from these modes without turning off the tester. Long press of the Test button - exit the cyclic mode and restart the test.
8. Fixed calculation of the capacitance of diodes at a reverse voltage of 5V (negative capacitance values are no longer displayed for germanium diodes).
9. Added calculation and display of base-emitter capacitance (Cbe) for BJT.
10. Added auto-detection of silicon and Schottky/Germanium diodes with the display of the corresponding designations in the 1st line.
11. For a more accurate assessment of the quality of the potentiometers(trimmer), a display of its total resistance between contacts 1-3 has been added, as well as the percentage of resistances R1<=>R2.
12. There are now 8 full active lines in the menu without an unnecessary "Mode-Select" line. The page mode of the menu display is enabled, which increases the speed and convenience when moving through the items.The "Turn off" item is highlighted in a separate color.
13. To save memory space, the ESR in-circuit measurement mode has been removed.A similar mode can be obtained using the cyclic capacitance measurement point on terminals 1-3.
The screenshots below compare the standard firmware and the modified one
 I will answer questions about receiving this modified firmware in my personal message!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 25, 2022, 08:12:34 am
A year has passed since the publication of the changes for ST7735 TTesters, posted on page 277. During this time, many changes have accumulated for the software from Karl-Heinz. The images of the elements and the program code for their display have been redesigned. Here are the new firmware, they were tested on my homemade products with ILI9341. I have no way to test on ST7735. There may be comments, write in a personal mail.
Here are pictures of some of the changes.

Added Mega64_T7 to ST7735 and similar changes for my version of Hiland M644
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on September 26, 2022, 06:03:55 pm
New modification English k-firmware for GM328A(AY-AT) based on the current 899th revision 1.13K.Quartz 8 or 16 MHz.Font 8x15.


Thank you, but where to find it for download?
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on September 27, 2022, 06:44:45 am
what about 0.91" 128x32 OLED ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 28, 2022, 10:00:58 am
I tried to add for BJT transistors measurement of junction capacitance be - Cbe. There are problems with darlington transistors with internal resistors and epitaxial transistors. With the latter, the problem was solved, but there may be other problems.
I offer the RGB version for testing. Comments and bugs are welcome...

P.S. there is not enough memory for the ATmega328, I had to refuse to show component icons on the screen. All other functions of the TTester are preserved.
Title: Re: $20 LCR ESR Transistor checker project
Post by: techie on September 28, 2022, 07:55:09 pm
Hi,

I was able to configure ComponentTester-1.47m firmware to work properly on a LCR-T5 meter, based on the STRIP_GRID_BOARD = 5 LCD port mapping found in Karl-Heinz firmware. In order for the LCD contrast to work properly within the LCD_CONTRAST range of 1-63, a minor edit to ST7565R.c was required:

The lines:
/* set contrast: resistor ratio 6.5 */
LCD_Cmd(CMD_V0_RATIO | FLAG_RATIO_65);

should be changed to:
/* set contrast: resistor ratio 4.5 */
LCD_Cmd(CMD_V0_RATIO | FLAG_RATIO_45);

I've attached Markus v1.47m firmware binaries for the LCR-T5 tester :-DMM, along with the modified source files (Makefile, config.h, config_328.h, and ST7565R.c) needed for re-compiling  :-/O:

Hope this helps!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 29, 2022, 09:54:19 am
Has your LCR-T5 a case similar to the TC-1 and includes a LiIon battery? Or is it just a red PCB with two bush buttons at the bottom right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on September 29, 2022, 01:46:45 pm
OLED 128x32 works after modifying LCD_Init in SSD1306.c, line 751:

for normal display:
Code: [Select]
  // scan config
  LCD_Cmd(CMD_COM_CONFIG_SET);
  LCD_Cmd(0x20);

for rotated display:
Code: [Select]
  // scan config
  LCD_Cmd(CMD_SEGMENT_MAP);
  LCD_Cmd(CMD_COM_SCAN_DIR);
  LCD_Cmd(CMD_COM_CONFIG_SET);
  LCD_Cmd(0x02);

probably it would be useful to add condition flags OLED_32 and OLED_32F for normal and flipped display in Makefile or config.h ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Danyit on September 30, 2022, 03:58:48 pm
Hello I have the DIY Kit "‘AY-AT"’ or GM328A, with your help I Updated it with the wonderfoul M firmware (I also updated with the latest revision).
Now I am here looking for info about cap checking.
I use this 3 function for cap checking:
1) general function for component check (Capacity, ESR and Leakeage)
2) ESR (capacity and ESR NO leakeage information)
3) Cap Leakage (charge and discharge)

For Esr checking, I usually use Function 1 and 2 (they give same result). For reference I use Typical Esr values tables, founded online.
With function 1 I can aslo check for leakeage, comparing the result with the following table, founded in the manual.
10 - 220UF 1-3UA
330 - 470UF 4-5UA
470 - 820UF 4-7UA
>1000UF 5-7UA

But now for function 3 what can I do? What I have to check?

I think that if a Cap pass all the test, it should be ok, Am I wrong?
Thank you, for your support
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 30, 2022, 05:13:24 pm
There's no simple answer. Based on the capacitor type the leakage current can vary a lot. An idea would be to compare the leakage with a cap of the same type and known to be good. Some dataheets might give a hint. Also be aware that it's a low voltage test. For a proper leakage check you would need a tester able to provide the voltage the cap is rated for.
Title: Re: $20 LCR ESR Transistor checker project
Post by: techie on September 30, 2022, 05:51:27 pm
@madires   Yes, my LCR-T5 has a case similar to the TC1 and a Li-ion battery.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 02, 2022, 11:28:29 am
Added measurement of Cbe for BJT and Cg for JFET transistors for Hyland M644. The display is clearly not suitable for such changes. I made two firmware for fonts 7x12 and 6x8. If anyone needs it please post your comments.
In the measurements, I highlighted the Darlington transistor in red and showed the measurements of this transistor on the "m" firmware and the datasheet of this transistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on October 03, 2022, 11:16:54 am
is it possible to keep measured value indication between measurements,
show status (probing/not found/element type/battery status)
in upper line (or in upper right corner) ?

its not very convenient when it clears on every measurement...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2022, 12:20:29 pm
Would the auto-hold mode help (next probing cycle is triggered by a button press)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on October 03, 2022, 12:51:16 pm
not always, sometimes its desirable to work in auto-restart mode (sorting of components, measuring of value change etc)...
simply don't clear whole screen, just rewrite element type/values

and somehow to disable TP2 pin probing, for false detections
(using resistor pullup/down on some pin, or in config)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2022, 02:18:11 pm
Then maybe the 'monitor' functions?
Title: Re: $20 LCR ESR Transistor checker project
Post by: boneDragon on October 03, 2022, 03:37:18 pm
thats it
is it possible to add to this diode/LED junction measurement, E24/E96 values with resistance continuity buzzer,
and make "monitor" as default mode on power-on, with working long-click for power-off, double-click for menu etc ?...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2022, 06:41:22 pm
A diode/LED monitor shouldn't be too hard to add. The other features would screw up the UI concept and might be an idea for an alternative firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on October 04, 2022, 01:07:48 pm
I know the porting to a 3.3v mcu question gets asked a lot and shot down because 5v is superior, but i was thinking of how split transformers have a negative, 0v and positive output. some of the transistor testers use two 3.7v cells in series.
Could a pair of cells be tapped in the middle for 0v and run a pair of 3.3v mcu in a split rail setup. that way you could get 6.6v of range, superior to the 5v mcu.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 04, 2022, 05:37:54 pm
The reason for 5V is that more components can be detected than with 3.3V. Placing two 3.3V MCUs in series won't work because they will be exposed to voltages out of spec. One solution for using a 3.3V MCU is to add an external switching matrix plus ADC which make things more complex and expensive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on October 04, 2022, 06:20:29 pm
Ah I see.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jwperry on October 07, 2022, 11:12:32 pm
Hey guys, quite the thread!

So like many of you, I purchased a random tester off of ebay several years ago and noticed some limitations that might be rectified by better firmware. Going off of the clones folder, I believe I have a MK-328. I attempted to flash Karl-Heinz Kübbeler's firmware based off some instructions from a Russian blog, but sadly I don't speak Russian and might have messed up some fuse settings. In addition, I was unable to dump the original firmware prior to flashing as I believe the chip was set to not allow dumping. (I'm not super knowledgeable when it comes to this stuff). Anyway, I am attaching images showing the unit, the board, the original fuses and lock bit settings, and the output from avrdudess. As it stands, a single button press will turn the screen on and then eventually fade to black after about 10 seconds.
Any input would be appreciated
-John
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 08, 2022, 08:22:02 am
jwperry,try to fill in the firmware that I attached below.
Download the archive, unzip it to the root of the disk from your computer. There should be no long paths to the firmware source files, as you have shown in your screenshots.
Now the fuses - they should be like this
fuses_lo = 0xf7
fuses_hi = 0xd9
fuses_ext = 0xfc
lock_byte = 0xff
Title: Re: $20 LCR ESR Transistor checker project
Post by: jwperry on October 08, 2022, 09:24:30 pm
indman,
Thanks for getting back to me. I have updated and set the fuses and lock bit. I attempted flashing the firmware you shared with me and now I am getting strange characters on screen. This only happens once. If I pull the battery from the unit and reinstall then I get the same "fade to black" behavior. I have attached a photo of the unit and a screenshot of avrdudess when using your firmware. This was flashed from a short path. Thanks again
-John
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 09, 2022, 08:22:03 am
Try 2 more firmware versions from the archive that I attached.The fuses are exactly the same as I wrote before. What will be on the display in this case?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 09, 2022, 08:40:13 am
Question to users of my firmware. Do I need to include in the firmware ??? The memory of the ATmega 328 is at its limit.
Improved the measurement of single diodes. Expanded the measurement of the forward voltage drop with a measuring resistor of 470k (in the original texts at 680 Ohms). Here are measurement examples for various types of diodes ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on October 10, 2022, 08:30:32 pm
Is there anything one should pay attention to when getting a GM328A from China? I read something from "old batches" or "round edges". I want to flash custom firmware and replace crystal (16MHz). Would this (https://www.aliexpress.com/item/1005002033157250.html) be a good pick? They call it 'new version'.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jwperry on October 10, 2022, 09:58:05 pm
indman,
We are starting to get somewhere. Both versions boot and allow for testing of components. I just using a 4700uf 35v cap for testing purposes. However there is still some interesting behavior from the tester. I can test components with the Chinese NoStripe firmware but the display font is very dim.  On the third firmware the font takes a second to "warm up" but is eventually bold and legible.  Also the third firmware keeps requesting calibration which I attempted. I can test a component with the third firmware and I receive values but it does ask for calibration each time. I may need to read the documentation on how to properely calibrate. I would start wondering about components on the board or the display itself, however, when flashing the first firmware you provided (with the odd characters), the font is is completely fine.

Breakdown:
First Firmware: Bold, legible odd characters
ChineseNoStripe: Faded hard to read, tests components successfully
Third Firmware: Screen looks mostly fine. Tests components successfully, but might have some calibration issues

Thank you for your efforts so far sir!

-John
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 11, 2022, 07:23:43 am
I want to flash custom firmware and replace crystal (16MHz). Would this (https://www.aliexpress.com/item/1005002033157250.html) be a good pick? They call it 'new version'.
If this clone has a BGR gamma display, it cannot run at 16 MHz. See page 277 for details.

For "k" firmware corrected the measurement of Darlington transistors. Source and pictures are attached. The source requires more memory, check for exceeding the limit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 24, 2022, 05:55:16 pm
For "k" firmware corrected the measurement of Darlington transistors.
What are the markings on the transistors you showed in the screenshots?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on October 25, 2022, 03:51:34 am
What are the markings on the transistors you showed in the screenshots?
These are NPN transistors - KT972B, PNP - 2SB1093 - datasheet on the previous page.

New firmware, taking into account previously published changes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vever001 on October 26, 2022, 01:00:53 am
Hello everyone, and thank you for this great project!

I'm attempting to update my "Daniu" TC-1 clone with an atmega324pa.
I did not make any hardware modifications yet (no 10uF cap, no mod).
The v1.34m hex from the Yandex repo works fine https://disk.yandex.ru/d/yW8xa5NJgUo5z/LCR-%D0%A2%D0%A11/Firmware/Markus%20Reschke/English/16MHz

I'm now trying to compile the latest v1.47m but all I get is a white screen and I need to unplug the battery.
Here are the changes I made from the original v1.47m: https://github.com/vever001/Transistortester-Warehouse/compare/39cf8f2adc5921e460891bf5707916381a2d36cf...vever001:Transistortester-Warehouse:master
You can also check my commits here: https://github.com/vever001/Transistortester-Warehouse/commits/master

I don't know what's wrong... I tried to replicate the exact config from the yandex repo.
Can anyone spot the issue? or give any hints?

Thank you very much  :),
Hervé
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 26, 2022, 08:42:32 am
Have you tried the settings listed in the Clones file?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vever001 on October 26, 2022, 11:19:21 am
Ok I started again from scratch, applied the clones instructions and it works perfectly now... Sorry for that :palm:
Here's my config if anyone wants it (for a Daniu TC-1 with atmega324pa): https://github.com/vever001/Transistortester-Warehouse/commits/clones-settings

I made some more changes:
- flip the LCD X and Y (screen was upside down)
- remove the LCD offsets (pixel lines were showing up at the edge)
- use 8x16 cyrillic font (some chars were not showing properly)
- enabled UI_AUTOHOLD (for convenience)

Now I can start digging in the options and hardware mods :)

Thank you for the amazing work,
Hervé
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 29, 2022, 08:37:26 am
New! :)
Updated the comparison table of clones  - added 2 devices on fake microcontroller and a clone on LGT8F328.
Be careful when choosing a device to purchase from Chinese friends!  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxFrister on October 29, 2022, 03:59:57 pm
I bought a T7 ("LCR-T7(2)"?) recently to try. It appears to mostly work except for zener testing.

For low voltage zeners, it seems to test but test high.

For high voltage (>20V) zeners, it seems to power them as soon as connected even before test button is pressed.  Reports results but high.  However the zeners are hotter than the sun after removed.

Before I open the case and void my warranty ;-) I wanted to check that this is not  the expected behavior.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 29, 2022, 04:29:36 pm
IIRC, the boost converter of the TC-1, T7 and the other models with the same case is running as long as the tester is powered on.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 29, 2022, 05:16:35 pm
MaxFrister,In all TC clones, the current in the tested zener diode is limited by a resistor of a certain value in units of milliamps(no more than 5mA). If the zener diode being tested is very hot, this means that a more significant current flows through it, which can damage it.This is a malfunction!Open a dispute with the seller, unless of course you somehow shorted the K-A contacts between each other or with one of the test contacts 1-2-3.Then you are the culprit of the malfunction.

 I also have a suspicion that you have a clone inside with a fake processor. You are no longer the 1st who complains about the heating of the tested zener diode.I think this malfunction is caused by a serious error in the circuitry of Chinese engineers. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxFrister on October 29, 2022, 06:44:44 pm
I'm pretty sure it is defective although I was unable to quantify how defective.  I tried to measure the current using a series resistor and managed to melt the probe grabber on my scope.  I don't think I'll try that again.

As for shorting K and A on the tester, I didn't do that but isn't that a normal diode failure mode?

Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 29, 2022, 06:49:48 pm
As for shorting K and A on the tester, I didn't do that but isn't that a normal diode failure mode?
This is really not dangerous if a current stabilizer or its limiter is provided in the circuit. If it is not present or it is incorrectly calculated, this will lead to the failure of the measuring port of the controller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 29, 2022, 09:32:26 pm
To characterize the boost converter you have in front, with the aid of your DMM:
a)you could measure the open-circuit voltage, it should be around 30V
b)then you could put a resistor, like 1K (around 1W to be on the safe side), and measure the voltage again, calculate the current, and check whether the internal current limitiation is working as it should. For testing a Zener, a few mA should be enough
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 30, 2022, 07:00:40 am
Feliciano,this measurement operation is true for the classical tester scheme. But in the clone version with a fake processor, the LM358 operational amplifier is present in the zener diode measurement circuit.What function does it perform in the scheme? A clear and understandable schematic diagram of the clone is needed to definitively determine the cause of this error. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on October 30, 2022, 12:03:53 pm
For sure an schematic (official or reverse-drawn) would be better, but as you know a boost converter should follow an inductive (classical) or capacitive (voltage multiplier) principle, and we could try to guess a rough Thevenin or Norton equivalents of it around a given operating point. If the zener gets too hot, the Voc is too high, and/or the internal resistance is too low. Knowing which is the case, a modification could be devised to the circuit, trying to make it safe.

Regarding the op-amp in this case, it could be part of a not-so-regulated (cheapo) boost converter, or it could be part of the V sensing for protecting the microcontroller. That would deserve analysis after the initial findings. On the other hand, an LM358 can only source a few tens of mA, bellow it's Vcc. That's why if I were MaxFrister, I would start by trying to understand how the circuit behaves and then think whether a mod can be made.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 30, 2022, 12:17:01 pm
Look closely at the PCB - pins A are shorted to ground through a 40 ohm resistor(59x)! The output voltage from the DC-DC switch (28V) is directly fed through the diode to pin K. It turns out that the current through the zener is limited only by this resistor and open diode (and it's ~ 0.7A!!!) That's why the diode D2 damage and the zener diode is very hot. If I saw the right track on the board. ;)
For the experiment I suggest you solder a 5-10 kΩ resistor in series with the diode.It's not hard mod.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 30, 2022, 05:16:02 pm
Look closely at the PCB - pins A are shorted to ground through a 40 ohm resistor(59x)! The output voltage from the DC-DC switch (28V) is directly fed through the diode to pin K. It turns out that the current through the zener is limited only by this resistor and open diode (and it's ~ 0.7A!!!)

Ouch! A constant current source with a BJT and a few diodes and resistors is simple and inexpensive. Just a series resistor causes a too large variation of the test current, which in turn also impacts the measurement (Zener voltage). AFAIK, the TC-1 and T7 Plus have a 10k series resistor. We would have less trouble if those cloners would stick to the recommended design instead of trying to cut even more corners.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 30, 2022, 05:21:45 pm
A constant current source with a BJT and a few diodes and resistors is simple and inexpensive.
You're right of course, a simple current constant regulator is called for in this design. But this is only one obvious problem that was detected. And I'm sure there will be others. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxFrister on October 31, 2022, 02:58:11 am
Look closely at the PCB - pins A are shorted to ground through a 40 ohm resistor(59x)! The output voltage from the DC-DC switch (28V) is directly fed through the diode to pin K. It turns out that the current through the zener is limited only by this resistor and open diode (and it's ~ 0.7A!!!) That's why the diode D2 damage and the zener diode is very hot. If I saw the right track on the board. ;)
For the experiment I suggest you solder a 5-10 kΩ resistor in series with the diode.It's not hard mod.

I was able to install a 5.1k resistor for current limiting.  I chose to install it after the cap rather than before.  I initially tried a 8.2k resistor but the tester reported a zener of 29.5V with nothing in the test socket.

On my unit, "A" is connect to ground via a 5-ohm resistor.  I'm not really sure why. 

It works now and best of all you can no longer use the DUT as a soldering iron.


Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 31, 2022, 05:41:23 am
I chose to install it after the cap rather than before.  I initially tried a 8.2k resistor but the tester reported a zener of 29.5V with nothing in the test socket. On my unit, "A" is connect to ground via a 5-ohm resistor.  I'm not really sure why. 
I'm not quite sure how you installed the extra resistor? Can you show a high quality photo of this section of your PCB with the resistor installed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on October 31, 2022, 06:10:25 am
I was able to install a 5.1k resistor for current limiting.  I chose to install it after the cap rather than before.  I initially tried a 8.2k resistor but the tester reported a zener of 29.5V with nothing in the test socket.

On my unit, "A" is connect to ground via a 5-ohm resistor.  I'm not really sure why. 

It works now and best of all you can no longer use the DUT as a soldering iron.
Try to play with that 5 ohm resistor instead of 5,1k. It seems that 5 ohm resistor is a shunt (current sensor) in current supply unit (similar to power supply for led). Put variable resistor in place of 5 ohm and try to change current using it.
It is just a theory, I don't have such a device to check. But if sdb628 is in use here then 120 ohm shunt should limit current to 5mA. 5ohm shunt should limit current to 120mA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mebel on October 31, 2022, 06:25:20 am
Sorry for obvious question.

The link doesn't work anymore. Where from can I download this file?

1. To download from the author's site at the link https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)  the current distribution kit of firmwares.
For this purpose to click in the bottom of the page on a line of ""Download GNU tarball"".

Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on October 31, 2022, 10:41:08 am
Sorry for obvious question.

The link doesn't work anymore. Where from can I download this file?

1. To download from the author's site at the link https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/ (https://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/)  the current distribution kit of firmwares.
For this purpose to click in the bottom of the page on a line of ""Download GNU tarball"".


https://github.com/kubi48/TransistorTester-source/ (https://github.com/kubi48/TransistorTester-source/)

https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/k-firmware (https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/k-firmware)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 31, 2022, 11:39:33 am
Try to play with that 5 ohm resistor instead of 5,1k. It seems that 5 ohm resistor is a shunt in current supply unit (similar to power supply for led). Put variable resistor in place of 5 ohm and try to change current using it.
MaxFrister If now you have nothing warmed up and check stabilitrons works fine, then do not touch anything else and listen to other silly advice, otherwise you risk to lose serviceable device!  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on November 01, 2022, 01:32:17 pm
Try to play with that 5 ohm resistor instead of 5,1k. It seems that 5 ohm resistor is a shunt in current supply unit (similar to power supply for led). Put variable resistor in place of 5 ohm and try to change current using it.
silly advice
Actually the advice can be not so silly.
Look. It is typical application of SDB628 in image1, it is voltage source:
[attachimg=1]
But SDB628 can be used as a current source, see image2:
[attachimg=2]
A current through D2 will be equal to 0.6/R2 (in case D2 rating is bigger than Vin).
If R2=5 Ohm, then the current will be 120mA.
If R2=40 Ohm, then the current will be 15mA.
Look at the image you posted more carefully and you will see that it is the case. So, there will be no 0,7A current there, just 15mA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 01, 2022, 01:43:41 pm
If R2=5 Ohm, then the current will be 120mA.
If R2=40 Ohm, then the current will be 15mA.
I don't need to explain the theory of how a simple chip DC-DC works.I can give you a big lecture about her work myself. The current of 15mA, and even more 120mA, which you have "calculated" is many times higher than the maximum permissible for checking a low-current zener diode. I repeat once again - do not give silly advice if you are 100% unaware of the complete connection scheme of the zener diode from Chinese "engineers".
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on November 01, 2022, 01:57:08 pm
Whole circuit is clearly visible in the photo you provided. You can see that it is the same as I provided in image2.
I believe that you have a big background in electronics, much bigger than mine.
But please don't be so aggressive, be more polite.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on November 01, 2022, 04:28:20 pm
Let me try to shed some light on the subject:
1.- Let's say the "designer" of this clone took the typical schematic from the boost converter datasheet, and forgot to add a current limitation (by mistake, or to save a few more cents)
2.- Let's say the boost can source 100mA and 30V (just a guess, I don't have measurements of the circuit with its chinese ICs):
2.1.- If you try to test a 30V zener, you are applying 3W to it (P=V*I). If it's an small zener (0.25W or 0.5W) you will fry it, or if supports it for short term, you would be testing it outside its intended operating window
2.2.- On the other hand, if the efficiency of the boost converter is around 85%, you will be asking close to 1A from the battery. For a small Li-ION battery, you will be exceeding the recommended C-rate
2.3.- If you put a small resistor in parallel to the zener, you will be lowering the maximum zener voltage you can measure, and for small-V zener (like 3.3V), you will still applying a lot of current to it, and drawing high current from the battery, whether you're testing a zener or not
2.4.- If you modify the IC voltage divider, you will be still lowering the open circuit output voltage, but not limiting the current
Therefore, as madires suggested, the best mod for a circuit like this it would be to add a current limiter, or if space is a problem, at least a series resistor, as indman suggester earlier (just make sure to add it before the measuring loop)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 01, 2022, 04:46:17 pm
A competent and simple solution, as indicated in the screenshot. Selection of the most optimal current and its stabilization for safe testing of high-power and middle(low)power zener diodes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxFrister on November 02, 2022, 03:45:32 am
I'm not quite sure how you installed the extra resistor? Can you show a high quality photo of this section of your PCB with the resistor installed?

Attached is a picture of my ugly fix as well as an attempt at reverse engineering of the LCR-T7 zener test circuit.

It looks to me like the resistor R16 is bad and that it is intended to control the feedback pin of U7 in constant current mode (0.6V/60R = 10mA).   
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 02, 2022, 06:46:22 am
On my unit, "A" is connect to ground via a 5-ohm resistor.  I'm not really sure why. 
Why do you think that R16 on your board has a resistance of 5 ohm? The internationally coded 59X stands for 40.20 ohms ± 1%.
Your board has exactly the same resistor rating as the one I showed in my example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxFrister on November 02, 2022, 01:55:40 pm
Why do you think that R16 on your board has a resistance of 5 ohm?

That is approximately what it measures in circuit.  I can pull it and measure it accurately tonight.

Does anyone know what IC U7 is?  It is not the SDB628 mentioned above; the pin wiring does not match.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 02, 2022, 02:07:01 pm
That is approximately what it measure in circuit.  I can pull it an measure it accurately tonight.
Does anyone know what IC U7 is?  It is not the SDB628 mentioned above; the pin wiring does not match.
U7 is very similar to SY7208CABC in the location of the contacts, but this cannot be said with 100% certainty, because the HYDSI or HYDWE marking does not appear anywhere yet.

P.S Here is an even more likely interpretation of U7 - this is AN_SY7200A (marking HY6VE). If you believe the documentation for this chip, then the output current is calculated by the formula I=0.2/R1. If R1 = 40 ohms, then the test current I=0.2/40=0.005A, that is, 5mA.

Now it remains to solve the riddle from Chinese friends -why does this circuit not withstand a given R1 current and allows it to conduct a much higher current?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on November 02, 2022, 03:46:40 pm
Because of open circuit. There is no load to inductance if you do not measure zener diode and there is no current, there is no voltage drop at current sensor resistivity and IC tries to add more and more power, it works at its maximum, it loads a lot of power into inductance and inductance generates high voltage pulses. And these high voltage pulses from inductance go to both capacity and IC itself. Both of them get fried in some time. If there is a big current then it means that feedback part of IC has already been fried and resistance between pins 2 and 3 is very small (shorted), such fried IC continues to work but with no ability to adjust the current by mean of that 40 ohm resistor any more.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 02, 2022, 04:10:42 pm
It is possible, although according to the documentation, this chip should have good overload protection for mode of open circuit.
And here is also an important note from the datasheet, which should be taken carefully:
"6) If the system chip interfacing with the EN pin has a
high impedance state at shutdown mode and the IN pin
is connected directly to a power source such as a Li-Ion
battery, it is desirable to add a pull down 1Mohm
resistor between the EN and GND pins to prevent the
noise from falsely turning on the regulator at shutdown
mode."
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on November 02, 2022, 04:23:48 pm
Low quality of these ICs I think...
We know that it can be not easy task to purchase good quality electronics parts from China. Maybe fnirsi have purchased defective ICs for their devices.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 02, 2022, 04:26:24 pm
Low quality of these ICs I think...
On this most likely assumption, I certainly agree with you. Probably a fake of chips, which is similar to the same fake of microcontrollers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxFrister on November 05, 2022, 02:38:50 am
Why do you think that R16 on your board has a resistance of 5 ohm? The internationally coded 59X stands for 40.20 ohms ± 1%.

I ran some measurements on my board.  First I returned it to it's original configuration and measured the current.  Testing a 2V zener, it uses 52mA.

I removed R16 and measured it out of circuit.  It measures 40 ohms as you expected.  I returned it to the circuit and it measures ~7 ohms. 

I think it is likely that U7 is bad. 

Does zener testing work on any LCR-T7 boards?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 05, 2022, 07:27:58 am
I returned it to the circuit and it measures ~7 ohms. I think it is likely that U7 is bad. 
Yes, you have a faulty U7! 7 ohms is the resistance between 2 and 3 pins of U7!
If you find an original high-quality SY7200A and install, then testing zener diodes will work fine on your clone.Also, according to the documentation in the circuit, it is desirable to install an X7R type capacitor at least 2.2 mkF(low ESR) at the output voltage, as well as to ensure a minimum load on the chip in the form of a resistor (pick up the nominal value), which will exclude possible self-excitation of the circuit in idle mode(open circuit).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on November 05, 2022, 10:41:31 am
It was possible to obtain acceptable measurement results of the TTester using the Mega2560. Additionally, I installed capacitors and replaced the capacitor with AREF. Scheme and examples of measurements in the pictures.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 05, 2022, 03:24:25 pm
The ATmega2560 also has sufficient pins for driving larger displays (ILI9481, ILI9486 or ILI9488) via 8-bit parallel bus.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ozkarah on November 07, 2022, 12:00:37 am
I have a new BSIDE ESR02 Pro. I want to check which firmware it came with but no FW version is published either on the boot screen, or in menu options.
Does anyone know how to learn which fw it has and which version?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 07, 2022, 11:29:52 am
IIRC, they come with a modified older k-firmware. You can update the firmware to the latest k or m-firmware if you like.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Martini on November 12, 2022, 01:28:25 pm
I'd like to buy my first (and hopefully last) component tester. Could you advise me the right hardware and firmware depending on my requirements?
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on November 12, 2022, 02:38:56 pm
hello,
does anyone here know this version with socketed µC and may know a source of purchase ?
regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 12, 2022, 04:14:17 pm
I'd like to buy my first (and hopefully last) component tester. Could you advise me the right hardware and firmware depending on my requirements?

Please see https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf for an overview.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 12, 2022, 04:31:06 pm
does anyone here know this version with socketed µC and may know a source of purchase ?

Looks like an LCR-T7 with ATmega328. You can get them from most shopping platforms. However, finding the exact same one could need some effort as there are several different LCR-T7 models.
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on November 12, 2022, 04:36:09 pm
Hello everybody!
After updating the firmware I'm having some problems, could any friends help me solve this problem (M328_KIT_TFT)?

Firmware version 1.47m

config.h
#define HW_ENCODER
#define ENCODER_PULSES   4
#define ENCODER_STEPS    20
#define HW_REF25

Note: The device works normally with the original firmware


Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 12, 2022, 07:05:06 pm
Have you tried the settings for AY-AT / GM328A in the Clones file? And don't forget to program also the EEPROM.
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on November 12, 2022, 07:11:41 pm
Yes, I've tried several versions and the only one that works is version 1.12.

And I always update the EEPROM
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 12, 2022, 07:15:57 pm
After updating the firmware I'm having some problems, could any friends help me solve this problem (M328_KIT_TFT)?
Note: The device works normally with the original firmware

You have combined the files from the modified firmware with the original files yourself and compiling? Therefore, the display is chaos.
In order for the modified firmware to work well, you need to make changes in a very large number of source files and understand the whole mechanism of the author's algorithm.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on November 12, 2022, 07:25:21 pm
I modified the following files:
makefile
config.h
config_328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 12, 2022, 07:31:08 pm
In that case you need to clean the entire crystal before you update the firmware. I see in the screenshot you showed the remnants of code from the previous firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on November 12, 2022, 07:44:34 pm
Friend indmam, what would be the procedure to clean the crystal?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 13, 2022, 06:55:16 am
wandows,I don't know what shell you use. For example, in a very simple program AVRDUDE PROG 3.3 cleaning of the entire crystal is done by simply pressing the button which I have shown with a red arrow.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on November 13, 2022, 07:42:45 am
A small addition to the TTester circuit allows you to measure the frequencies of quartz and ceramic resonators. This is for testers that have an input for measuring frequency. The picture shows unsuccessful measurements of the Ttester according to the HilandM644 scheme, the first three pictures are the top row and measurements according to the attached scheme. For example, various measurements are given. The measurement range of the above circuit is 32 kHz - 4.5 MHz.
If you need to measure quartz resonators at high frequencies, use the 74HC4060, change the resistors and capacitors down and use a prescaler.
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on November 13, 2022, 12:16:19 pm
wandows,I don't know what shell you use. For example, in a very simple program AVRDUDE PROG 3.3 cleaning of the entire crystal is done by simply pressing the button which I have shown with a red arrow.

Hello friend indman!

I managed to solve it, and the problem was in the selection of the .HEX and .EEP files.

By a simple oversight I was selecting the .HEX file for the EEPROM.

Update completed successfully!

Thanks in advance for your attention and help!!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Martini on November 13, 2022, 01:25:54 pm
I'd like to buy my first (and hopefully last) component tester. Could you advise me the right hardware and firmware depending on my requirements?

Please see https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf (https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf) for an overview.

I did check it out but I'm not sure that's enough for me to make a decision :-\

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 13, 2022, 03:43:35 pm
I'll use it mostly for in-circuit capacitor testing, is there any difference ESR-wise?

No, but I'd recommend a dedicated in-circuit ESR tester (lower test voltage)

saw the m firmware could test capacitor leakage (like this (https://t.ly/2Rmb)?). How does it work, what hardwares can do it?

Works with standard probes, but only up to 5V. If you are playing with higher voltages better get a special leakage tester which can provide the voltages the DUTs are rated for.

Does the power supply make any difference? Like, will a tester using a 9V battery be able to generate a 9V signal from his function generator? Or test a higher voltage Zener diode?

Just 5V signals. However, the Zener check uses a separate boost converter up to 50V output. Some clones generate a test voltage around 25 or 35V, a few about 45V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: juvann on November 14, 2022, 07:13:55 pm
Very big and interesting thread, sorry if I don't read all pages, I tried to search my question without success.
I'd like buy a LCR-T7(2) and use the good alternative firmware madires, but I'd like also an interesting feature of Hiland M644 "quartz and ceramik resonators".
Is there a mod for support "quartz and ceramik resonators" in LCR-T7 and just enable it with define HW_FREQ_COUNTER_EXT?
I don't like Hiland M644 because use a not recharable battery, no ports protection and is not cheap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2022, 08:38:37 pm
If that model got two unused pins and if T0 is also available then it should be possible to add the extended frequency counter. The next challenge is to make it small enough to fit into the case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: juvann on November 15, 2022, 05:47:57 am
Looking at the schematics available online PB0 (T0) and other 3 pins are available
So I will buy and I will try the mod.
what will be the maximum frequency that can be detected?

Thank you madires for the help.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 15, 2022, 11:09:06 am
I don't know the max frequency supported by the hardware of the extended frequency counter but for the MCU the theoretical limit is:
   f_max = MCU clock * prescaler / 4
(prescaler is 16 or 32)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 15, 2022, 11:23:49 am
madires,are there plans future to add the SamplingADC function in your to doo list? ;)
External additional modules are, of course, good and they expand the capabilities of the tester.But if it is possible to use internal reserves and processor capabilities for the same purpose, then why not?
This is аctual true for a small portable device.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 15, 2022, 03:29:15 pm
Back then when Karl-Heinz added PA3FWM's idea of the SamplingADC I had a look at it and my first thought was that it's an interesting concept. On the other side I'd prefer a proper LCR meter when measuring such tiny values. Weighing up pros and cons I decided to not implement the SamplingADC. But if someone likes to implement it for the m-firmware I wouldn't hesitate to add the code.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 15, 2022, 04:03:15 pm
But if someone likes to implement it for the m-firmware I wouldn't hesitate to add the code.
This is definitely a great motivation for those who want to thoroughly understand PA3FWM's code, but this task does not seem too easy to me. Maybe I'm wrong. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: coromonadalix on November 15, 2022, 05:23:30 pm
I'm surprised to see the lack of mega 1280 - 1284  2560 series of arduino's  .... or diy  boards

With bigger display shield(s)  it could be evolved further without costing an arm

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 15, 2022, 05:50:07 pm
coromonadalix What do you think this is?  :D
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3119442/#msg3119442 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3119442/#msg3119442)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4504399/#msg4504399 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4504399/#msg4504399)
Title: Re: $20 LCR ESR Transistor checker project
Post by: BroMarduk on November 21, 2022, 04:23:58 pm
Not sure if this has been pointed out or not but there's a small bug in config.h

Line 2082 is where it starts:

This
Code: [Select]
/* variable Start_str */
#if defined (SW_OPTO_COUPLER) || defined (SW_DS18B20) || defined (SW_ONEWIRE_SCAN) || defined (HW_EVENT_COUNTER)
  #ifndef VAR_START_STR
    #define VAR_START_STR
  #endif
#endif

Should be:
Code: [Select]
/* variable Start_str */
#if defined (SW_OPTO_COUPLER) || defined (SW_DS18B20) || defined (SW_ONEWIRE_SCAN) || defined (HW_EVENT_COUNTER) || defined (SW_DHTXX)
  #ifndef VAR_START_STR
    #define VAR_START_STR
  #endif
#endif

At least that is the only way I can enable DHTXX without one of the others also enabled.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on December 01, 2022, 11:44:40 am
When setting up sampling_lc.c for the TTester on MEGA 2560, I noticed the dependence of low inductance readings on the connection to the inputs with direct and reverse switching. This dependence is also observed on other measuring instruments. See for yourself in the picture.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 04, 2022, 08:51:08 am
I don't know if that is an issue specific to the MEGA2560, but on other ctesters, I've noticed when I measure several times the same inductor --whithout moving it-- the results differ a little.

I haven't looked into the measurement subroutine, but maybe the method tends to let some remanent core magnetization. You may want to dig into that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 04, 2022, 11:52:33 am
The Transistortester uses DC for measuring inductance (standard measurement method, SamplingADC is a different story) while a proper LCR meter applies an AC signal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on December 04, 2022, 01:16:56 pm
I don't know if that is an issue specific to the MEGA2560, but on other ctesters, I've noticed when I measure several times the same inductor --whithout moving it-- the results differ a little.
No, the testimonies themselves are stable, all meaningful numbers. Indications have more value when connecting the lower output of inductance to the input "1" and less when connecting the upper output of inductance to the entrance "1". The method implemented in sampling_lc.c is very accurate. I only adjust it to the length of the internal compounds of the Mega 2560 in the range of 40 nH - 2 μH.

 Here is a fragment from ttester-1.13k en.pdf
"...Together with a parallel connected capacitor the inductor build a resonant circuit. With a
short current pulse this circuit begins to oscillate some times without further stimulation. With the
sampling method the frequency of this oscillation can be measured..."
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 05, 2022, 09:04:01 pm
The Transistortester uses DC for measuring inductance (standard measurement method, SamplingADC is a different story) while a proper LCR meter applies an AC signal.
Currently I have one WEI with K-fimware and one of the new T7 (not a 324) with Chinese firmware. IIRC, the SamplingADC is enabled for the first one, but I don't have both equipment in front of me to take some snapshots now.

When I measure some chokes or transformers, the first(s) measurement(s) gives me one value, and further measurements tend to give me different, but reasonable stable, values. That's why I think the measurement method perhaps uses more pulses in one direction than the other, therefore having some sort DC offset which in some cases is more noticeable than others. But you guys know the code better.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Spongey on December 06, 2022, 12:53:51 am
I finally took the plunge and got a random version from eBay. From the outside this looks identical to the LCR-TC1 version but inside it has the same PCB as LCR-T7(FNIRSI) AFAICS complete with a (presumably fake) chip marked as MEGA328P.

When you power it up in test mode it says FNIRSI-TC1, pauses at 38% but it does not report the firmware version at the end.

I was hoping to reflash it, never mind.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on December 06, 2022, 07:30:00 am
I propose a new version of the addition of the TTester circuit for measuring quartz and ceramic resonators in the range of 100 kHz - 20 MHz. The Chinese version HCF4060BE with a supply voltage of 6V and the use of an internal divider, allows you to measure quartz up to 20 MHz. Malaysian variant up to 16 MHz. I did not manage to lower the frequency for sentries (32768 Hz).

P.S. I apologize for some texts in Cyrillic, while debugging...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 06, 2022, 11:24:28 am
Firmware-wise it would be the extended frequency counter without the input selection. I could add it as a new counter variation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jemp on December 06, 2022, 04:37:59 pm
Hello
Got 2 LCR Testers today from AliXpress..  New LCR-T4 and LCR-T7 Color  
Both have new firmware version 3.12K  
Does anybody know where to find this firmware.. or is it a hoax..  mean Chinese Variants.. ?

tnx for info

JP
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 06, 2022, 05:15:19 pm
That's a modified k-firmware with fancy graphics and less features.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 06, 2022, 05:23:12 pm
New LCR-T4 and LCR-T7 Color 
Both have new firmware version 3.12K 
I'm not 100% sure, but these new firmware are protected for reading and are also designed for clones with Chinese-made microcontrollers. This is mentioned in my clone comparison table.;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on December 07, 2022, 08:12:35 am
Firmware-wise it would be the extended frequency counter without the input selection. I could add it as a new counter variation.
To use the 4060 as a driver pre-amplifier, the following circuit must be applied. A multi-turn variable resistor will allow you to accurately set the maximum conversion frequency.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jemp on December 08, 2022, 05:19:18 pm
Hello, like in  #7908 I have also a MK-328 , with PCB 1.0 Date 2014/07/14
I programmed it with 1.13k..
Seems to be 2-3 versions.. with light fonts, or thicker fonts..
So programming no problem at all..
I works OK, starts up etc.. will do calibrate etc..  BUT....
I wont shut off ! when no component in it.. it goes blank and restart always again, automatically

Any thoughts ?

Does anybody has the ORIGINAL Firmware 1.11 ?

Tnx Jemp
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 09, 2022, 11:56:42 am
The k-firmwmare has a setting for power management called POWER_OFF (in the Makefile). What have you set for POWER_OFF? Or have you disabled it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: jemp on December 09, 2022, 02:38:13 pm
Hi Markus
I did not compile the soft myself for the moment
I just flashed firm 1.13k, like attachment in msg #7910-11 and following
No firmware whatsoever closes the Tester Down... it resets itself constantly..
Could be a hardware failure..?
But I measures OK and perfectly.. just wont power off , after certain time
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 09, 2022, 03:07:57 pm
A common setting for POWER_OFF is 5, i.e. the tester will shut down after 5 consecutive "no part found" messages. You could also try to press the test button for a few seconds after the last result.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jemp on December 09, 2022, 08:33:46 pm
Tnx, Marcus for input
Found problem..  due to soldering new chip ATMEGA328P, i made short circuit, between pin 10-11  so turn-on and turn-off were connected..
My mistake;.
Firm 1.13K works TOP !! tnx Guys and Designers..

JP
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 13, 2022, 03:13:59 pm
New modification English k-firmware for clones LCR-TC1(LCR-TC2,T7) based on the current 899th revision 1.13K.Quartz 8,16 or 20MHz.Font 8x15.With 8MHz quartz there will be no option to test different resonators.

The firmware will work only on clones with installed ATMega644 MCU and ST7735 display!

The author's code has been supplemented and corrected in many places to speed up the work and best display the test results:
1. Improved font 8x15, added new symbols of inductance,zener diode,triac,thyristor, "eta" as well as large symbols UJT and PUT.
2. Test results (value data) are highlighted in a separate color.
3. A full pinout for 3 contact parts is always placed at the bottom of the display for convenience when sorting.
4. A new color icon has been added to assess the battery status.
5. Measure the zener diodes at the terminals of the voltmeter "A" - "K". The zener diode symbol will appear on the display if it is connected correctly, and on the 2nd line its breakdown voltage is Vz. If the zener diode is connected as a diode, only the forward voltage drop on it will be displayed on the display Vext.
6. Improved auto-detection of UJT and fixed the display of the transmission coefficient "eta".
7. The tester's algorithm has been changed for cyclic modes [RL] and [C] - now exit from these modes without turning off the tester. Long press of the Test button - exit the cyclic mode and restart the test.
8. Fixed calculation of the capacitance of diodes at a reverse voltage of 5V (negative capacitance values are no longer displayed for germanium diodes).
9. Added calculation and display of base-emitter capacitance (Cbe) for BJT.
10. Added auto-detection of silicon and Schottky/Germanium diodes with the display of the corresponding designations in the 1st line.
11. For a more accurate assessment of the quality of the potentiometers(trimmer), a display of its total resistance between contacts 1-3 has been added, as well as the percentage of resistances R1<=>R2.
12. There are now 8 full active lines in the menu without an unnecessary "Mode-Select" line. The page mode of the menu display is enabled, which increases the speed and convenience when moving through the items.The "Switch off" item is highlighted in a separate color.

I will answer questions about receiving this modified firmware in my personal message!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 13, 2022, 07:36:43 pm
And another one:

v1.48m
- Added remote command V_F_clamp for V_f of clamping diode for Schottky transistors.
- Pin assignment for the 3 test pins/probes can be changed now (suggested by dreieck@mikrocontroller.net).
- Optional confirmation beep for valid frame/packet in IR receiver/decoder (SW_IR_RX_BEEP) or after probing is done (UI_PROBING_DONE_BEEP).
- Updated license to EUPL v. 1.2.
- Option to center-align infos and some other texts (UI_CENTER_ALIGN).
- Option to show self-discharge voltage loss of a capacitor > 50nF (SW_C_VLOSS, suggested by indman@EEVblog). Also added as remote command.
- Option to show additional info for a possible potentiometer/trimpot (SW_R_TRIMMER)
- Workaround option for clones with SCT15L104W management MCU, in case the tester turns off suddenly after the first probing cycle (PASSIVE_POWER_CTRL, based on idea from lhlad@EEVblog).
- Added option to switch boost converter for Zener check by a dedicated I/O pin (ZENER_SWITCHED, suggested by Per Hansson@EEVblog).
- New option to display values in a different color (UI_COLORED_VALUES, suggested by indman@EEVblog).
- Added precompiler check for detecting if multiple displays are configured (suggested by Per Hansson@EEVblog).
- Moved supporting configuration management from config.h and config_<MCU>.h to a new header file (config_support.h). Also added a few additional configuration checks. Fixed issue with missing text for SW_DHTXX (reported by BroMarduk@EEVblog).
- Moved UJT symbol bitmap to standard symbols.

Please download at:
- https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
- https://github.com/kubi48/TransistorTester-source/tree/master/Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: Adrian_Arg. on December 14, 2022, 03:03:21 pm
very silly question, has anyone made a video of the complete process to make the hex and epp files, using the files downloaded from here
very silly question, has anyone made a video of the complete process to make the hex and epp files, using the files downloaded from here (http://very silly question, has anyone made a video of the complete process to make the hex and epp files, using the files downloaded from here)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 14, 2022, 03:12:53 pm
For example: https://www.youtube.com/watch?v=P5zWMnvjfM4 (https://www.youtube.com/watch?v=P5zWMnvjfM4)
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on December 16, 2022, 03:05:33 am
Quick question, please. I have an LCR-T4 I bought years ago. Will I get the extra functionality present in other versions of the tester if I flash this firmware, please?
https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk/mega328_T4_v2_st7565
I mean stuff like leakage currents for transistors, and all the extra goodies the GM328 has. Or those things are device specific?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 16, 2022, 10:00:28 am
I have updated the comparison table of the most popular clones, taking into account the release of the new 1.48m
https://yadi.sk/d/yW8xa5NJgUo5z  ;)
I have also updated the Russian-language pdf format instruction for 1.48m as well as the change log file CHANGES.ru ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on December 16, 2022, 10:56:20 am
OK, I managed to brick my T4. I flashed the firmware using:

avrdude -p m328p -P usb -c usbasp -U flash:w:mega328_T4_v2_st7565.hex

Now I have a black screen at all times. Any ideas, please? Do I need to also flash the eep file or something?
Thanks

EDIT: Here's the avrdude command output:

Code: [Select]
avrdude: warning: cannot set sck period. please check for usbasp firmware update.
avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.04s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
         To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: warning: cannot set sck period. please check for usbasp firmware update.
avrdude: reading input file "mega328_T4_v2_st7565.hex"
avrdude: input file mega328_T4_v2_st7565.hex auto detected as Intel Hex
avrdude: writing flash (29334 bytes):

Writing | ################################################## | 100% 18.99s

avrdude: 29334 bytes of flash written
avrdude: verifying flash memory against mega328_T4_v2_st7565.hex:
avrdude: load data flash data from input file mega328_T4_v2_st7565.hex:
avrdude: input file mega328_T4_v2_st7565.hex auto detected as Intel Hex
avrdude: input file mega328_T4_v2_st7565.hex contains 29334 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 16.90s

avrdude: verifying ...
avrdude: 29334 bytes of flash verified

avrdude: safemode: Fuses OK (E:FD, H:D9, L:F7)

avrdude done.  Thank you.

EDIT2: Oh, I erased the entire flash memory and now I need to burn the bootloader again, right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on December 16, 2022, 11:45:48 am
Oh! I needed to flash the eeprom file as well, of course! In case someone finds this and it helps, this is the command that worked for me:

avrdude -p m328p -P usb -c usbasp -U flash:w:mega328_T4_v2_st7565.hex -U eeprom:w:mega328_T4_v2_st7565.eep
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 16, 2022, 02:54:44 pm
Quick question, please. I have an LCR-T4 I bought years ago. Will I get the extra functionality present in other versions of the tester if I flash this firmware, please?
https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk/mega328_T4_v2_st7565
I mean stuff like leakage currents for transistors, and all the extra goodies the GM328 has. Or those things are device specific?

Yes! Please see https://github.com/kubi48/TransistorTester-source/tree/master/trunk for the latest version. No, only hardware specific options. However, the flash size might limit the features available.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on December 16, 2022, 04:06:40 pm
Quick question, please. I have an LCR-T4 I bought years ago. Will I get the extra functionality present in other versions of the tester if I flash this firmware, please?
https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk/mega328_T4_v2_st7565
I mean stuff like leakage currents for transistors, and all the extra goodies the GM328 has. Or those things are device specific?

Yes! Please see https://github.com/kubi48/TransistorTester-source/tree/master/trunk for the latest version. No, only hardware specific options. However, the flash size might limit the features available.

Thanks, madires. I'll try those as well... In a while, after I replace the LCD screen, cause I managed to rip the connector off. Oh well  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 17, 2022, 06:05:58 pm
That is approximately what it measure in circuit.  I can pull it an measure it accurately tonight.
Does anyone know what IC U7 is?  It is not the SDB628 mentioned above; the pin wiring does not match.
U7 is very similar to SY7208CABC in the location of the contacts, but this cannot be said with 100% certainty, because the HYDSI or HYDWE marking does not appear anywhere yet.

P.S Here is an even more likely interpretation of U7 - this is AN_SY7200A (marking HY6VE). If you believe the documentation for this chip, then the output current is calculated by the formula I=0.2/R1. If R1 = 40 ohms, then the test current I=0.2/40=0.005A, that is, 5mA.

Now it remains to solve the riddle from Chinese friends -why does this circuit not withstand a given R1 current and allows it to conduct a much higher current?

I recently purchased one of these so-called "improved" LCR-TC1 transistor tester units. U1 (MCU) is mislabeled as a Mega328. The display shows "FNIRSI" when performing the self-calibration. This tester contains the U7 circuit (as discussed in this thread) to generate 30V DC for testing zeners.

For me the zener test feature worked properly a couple of times without excessive zener current, but then it failed in the mode where the zener test current isn't limited.
After it failed I measured up to 500mA into a short circuit placed on the K and A terminals. I did this test very briefly. Fortunately conducting this short-circuit current test one time did not cause any additional failures. The U7 circuit continues to generate 30V (but without any current limiting). All other functions of the tester still work OK.

I believe the failure occurred when I connected an 11V zener across the K and A test terminals while the tester was already powered up.

Here is what I suspect causes U7 to fail:

1) When powered up with an open circuit on the K and A terminals, U7 continuously generates the full 30V DC output. The filter capacitor on the 30V rail, although small, still holds a substantial amount of energy when charged up to 30V.
2) Connecting a component across K and A can immediately dump the entire 30V directly into the current sensing pin of U7, causing this pin to permanently short circuit.
3) According to the U7 datasheet the current sensing pin is only capable of handling 4V

To prevent the failure of U7 I intend to experiment with placing a resistor of perhaps 4K7 or 10K between the high end of the 40 ohm sensing resistor and the current sensing terminal of U7. Hopefully this will prevent failures of U7. The worst case test will be to have the tester powered up and then apply a short circuit between K and A.

U7 is intended for use as a current-limited LED driver. In this application the string of LEDs is permanently connected. Therefore the current limit will activate gradually as the output voltage rises soon after power up. In this case the feedback loop is always closed, preventing excessive voltage from reaching the current sensing pin of U7.

But in the transistor tester application, the output voltage rises to the full 30V when K and A are open circuit. The output voltage rises to 30V because the current-limiting feedback loop is open. Then, when a short-circuit or low resistance is applied across K and A, the entire 30V is instantly dumped into the current sensing pin of U7. This is what damages U7.

I will post my results after testing. First I must obtain a supply of replacement U7 chips. I will try to get several types that have the same pinout, including the SY7200A.

-EB
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on December 20, 2022, 12:50:00 pm
And another one:

v1.48m
- Added option to switch boost converter for Zener check by a dedicated I/O pin (ZENER_SWITCHED, suggested by Per Hansson@EEVblog).
Here is a little picture to go together with this new option for the Hiland Elec M644 based on Indman's schematic, maybe someone can find it helpful :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 21, 2022, 01:26:00 am
OK, I managed to brick my T4. I flashed the firmware using:

EDIT2: Oh, I erased the entire flash memory and now I need to burn the bootloader again, right?

A bootloader is not needed when programming the AVR MCU with the ISP header.
(On the other hand a bootloader is required to program Arduino boards via a serial or USB port. It’s easy to get confused about this.)

Upgrading transistor tester firmware always requires programming the flash and the eeprom.

Generally the fuse bytes require no changes (except possibly when changing the frequency of the crystal from 8MHz to 16 or 20MHz - could the experts please comment on this?)

Programming of the fuse bytes is required when a virgin (never used before) AVR MCU is programmed for the very first time. The factory default is 1MHz internal clock. Therefore the fuse bytes must be changed to “external crystal oscillator” or else the transistor tester will operate at only 1/8 of its normal speed.

-Elecdonia
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on December 21, 2022, 06:16:25 am

To prevent the failure of U7 I intend to experiment with placing a resistor of perhaps 4K7 or 10K between the high end of the 40 ohm sensing resistor and the current sensing terminal of U7. Hopefully this will prevent failures of U7. The worst case test will be to have the tester powered up and then apply a short circuit between K and A.
It will cause quite a big additional power consumption by device (additional 40mA or something like that) (my misunderstanding, I didn't catch the place of that resistor you proposed).
You can put protective diode or zener diode in parallel to that 40 ohms resistor. Diode will not allow over voltage on U7 sensor pin, it will cut voltage to 0,7v.

But we have to think about a case user shorted A and K terminals - in this case U7 will produce voltage near (Ubat - Vschottky) = 4v and it will be applied directly to our diode. The diode may be burned if we do not limit current. We can put 100 ohms resistor between output capacitor of U7 and K-terminal - it will limit current through diode (Ishorted = (4v-0,7v)/100ohms = 33ma). Voltage drop on this resistor in normal situation (measuring zener diode) will be equal to (100 ohms * 5mA) = 0,5v - it is very low and it should not affect zener detection functionality of TT.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrAl on December 21, 2022, 01:28:19 pm
This is a reply to the very first post...


Hello there,

If you get a scope and frequency generator you can test for all those things and get the error down to a very low value.  This is especially useful for cap ESR which is an important specification.

Also, these little meters will never be able to read inductors except for the very small ones maybe, and maybe only air core inductors.  That's because inductors with metal cores require some excitation current to be able to get a good idea what the inductance is, and the inductance changes with DC bias so you need a way to change that also.  Sometimes the only way to measure inductors like this is to measure their characteristics while they are actually in the circuit they are going to be used in, such as a buck converter.
These harder to measure inductors include 50/60Hz line frequency inductors and switching regulator inductors as they usually have some type of specialized metal core which makes them very DC bias sensitive as well as frequency sensitive.  You can usually measure ESR with an Ohm meter for these types though.

To measure cap ESR, you can put some resistance in series with the cap and use a square wave to energize the circuit.  Looking across the cap with the scope will show a waveshape that can be analyzed that will reveal the capacitance and the ESR.  The ESR shows up as a very vertical part of the wave and measuring the current thought the resistor on channel 2 of the scope and cap voltage on channel 1 will show you the ESR by simply dividing the voltage delta by the current delta for that vertical part.  A bad cap ESR shows up very vividly this way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 21, 2022, 01:35:23 pm
MrAl,why did you provide us with a full copy of the message February 23, 2013 from the 1st page of the topic? You could just make a short link to this post in the topic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 21, 2022, 01:47:31 pm
Generally the fuse bytes require no changes (except possibly when changing the frequency of the crystal from 8MHz to 16 or 20MHz - could the experts please comment on this?)

If you just change the frequency the fuse bytes don't need any changes..
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 21, 2022, 02:09:38 pm
Also, these little meters will never be able to read inductors except for the very small ones maybe, and maybe only air core inductors. 

The Transistortester isn't an LCR meter, but in can measure L, C and R to some extend. Get one, compare the results with a proper LCR meter, and you'll see that the Transistortester isn't that bad.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rsjsouza on December 21, 2022, 02:40:48 pm
Hello there,

If you get a scope and frequency generator you can test for all those things and get the error down to a very low value.  This is especially useful for cap ESR which is an important specification.
(...)
I agree with your remarks about the potential pitfalls when measuring inductors and capacitors, but the keyword is convenience: for a quick check these testers are exceptionally useful. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 21, 2022, 04:17:59 pm
Also, these little meters will never be able to read inductors except for the very small ones maybe, and maybe only air core inductors. 

The Transistortester isn't an LCR meter, but it can measure L, C and R to some extent. Get one, compare the results with a proper LCR meter, and you'll see that the Transistortester isn't that bad.
For years I’ve used the LC100-A to measure inductors & capacitors. The LC100-A excels at measuring small capacitors & inductors - uH & pF. That said, the LC100-A is also capable of measuring large values: 100,000uF, 50H. I recommend that everyone who enjoys using their transistor tester should consider adding the LC100-A to their test gear collection.

The LC100-A is a modern digital version of the legendary “ grid dip meter ” used by ham radio enthusiasts for nearly 100 years. It measures the unknown L or C by connecting it in parallel with an internal calibrated C or L. This forms a tuned LC circuit. An IC comparator with positive feedback drives the LC circuit into steady oscillation. Typical oscillation frequency is 1-500kHz. The internal MCU-based frequency counter measures the oscillation frequency and uses clever math to calculate and display the uH or pF of the unknown L or C.

Many Asian electronics vendors sell the LC100-A. Although quality/accuracy varies by vendor, the low cost ( < $25 USD ) allows exploring this device on a budget. The original LC100-A manufacturer is a company named MingHe. I have a genuine branded MingHe LC100-A which is quite accurate, often well within 2% when compared to high-end LCR meters. Try to find a vendor who shows a photo of the LC100-A with a MingHe label on the PC board. This is the one to buy.

Comprehensive discussions of the LC100-A may be found here:
https://www.antiqueradios.com/forums/viewtopic.php?f=8&t=365161 (https://www.antiqueradios.com/forums/viewtopic.php?f=8&t=365161)
https://www.eevblog.com/forum/testgear/lc100-a-a-precise-lc-meter-for-3-75$/msg4596301/#msg4596301 (https://www.eevblog.com/forum/testgear/lc100-a-a-precise-lc-meter-for-3-75$/msg4596301/#msg4596301)

-Elecdonia


Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 21, 2022, 04:22:03 pm
Generally the fuse bytes require no changes (except possibly when changing the frequency of the crystal from 8MHz to 16 or 20MHz - could the experts please comment on this?)

If you just change the frequency the fuse bytes don't need any changes..
Thanks!
I’ll soon be updating the firmware in one of my transistor testers. I also intend to experiment with changing the crystal from 8MHz to 16MHz.

-E
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 21, 2022, 04:24:57 pm
For several years I’ve been using a device known as the LC100-A to measure inductors and capacitors.
This information is certainly interesting to many on the forum, as well as information about measuring ESR using a generator and an oscilloscope. But I want to ask without offense - what does this information have to do with the project being discussed here? There are relevant topics for discussing these devices on the forum. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 21, 2022, 05:44:23 pm
For several years I’ve been using a device known as the LC100-A to measure inductors and capacitors.
This information is certainly interesting to many on the forum, as well as information about measuring ESR using a generator and an oscilloscope. But I want to ask without offense - what does this information have to do with the project being discussed here? There are relevant topics for discussing these devices on the forum. ;)
I agree: in this topic we should focus on the transistor tester.

My LC100-A post was intended mainly to call attention to a low-cost alternative device for measuring C and L. I was responding to several questions posted here about measuring L & C with the transistor tester.

I use my transistor testers several times per day. But I go to my LC100-A when L or C must be measured precisely, especially with RF circuitry.

To me the transistor tester represents an inexpensive device which every electronics enthusiast should have on their workbench. I am very appreciative of the efforts of the folks here on this topic who continue refining & maintaining the transistor tester project.

-E
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on December 22, 2022, 11:41:21 am
Also, these little meters will never be able to read inductors except for the very small ones maybe, and maybe only air core inductors. 

The Transistortester isn't an LCR meter, but in can measure L, C and R to some extend. Get one, compare the results with a proper LCR meter, and you'll see that the Transistortester isn't that bad.
For several years I’ve been using a device known as the LC100-A to measure inductors and capacitors.
Both authors inattentively read messages with examples of measurements. I gave measurements of small capacitances < 1 pF.
When it comes to measurements of small and large inductances, it is necessary to take into account the different measurement methods and frequencies at which measurements are made.
The top row shows the readings of the TTester when the turns of inductance are compressed and the readings of the measurement of large inductance. Below are the readings of this inductance on different RLC meters at different measurement frequencies.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 22, 2022, 04:04:16 pm
MrAl,why did you provide us with a full copy of the message February 23, 2013 from the 1st page of the topic? You could just make a short link to this post in the topic.
What is the method to insert links to other posts which are inside the EEVblog forums? The only instructions I can find in the forum help documents are for linking to URLs. I can do that OK. But I cannot yet link to an individual forum post. 
Thanks in advance!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 22, 2022, 04:13:02 pm
elecdonia, this is easy to do if you copy the link "Re: $20 LCR ESR Transistor checker project" in the browser and paste it through the globe icon "InsertHiperlink"  :)
For example, here is a link to the 1st post in the topic
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg195093/#msg195093 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg195093/#msg195093)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 22, 2022, 04:33:01 pm
Quote
To protect U7 I will try adding a series resistor (4K7 or 10K) between the high end of 40 ohm current sensing resistor and U7 current sensing pin.
It will cause quite a big additional power consumption by device (additional 40mA or something like that).

You can put protective diode or zener diode in parallel to that 40 ohms resistor. Diode will not allow over voltage on U7 sensor pin, it will cut voltage to 0,6v.
I will test your suggestion to connect diode in parallel with 40 ohm resistor.
Advantage: Addition of parallel diode doesn’t require cutting a PC board trace.

However, addition of 10K series resistor should not cause power consumption to increase. The input resistance of U7 current sensing pin is much larger than 10K. Therefore the series resistor is not expected to alter the operation of U7.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on December 22, 2022, 07:01:05 pm
However, addition of 10K series resistor should not cause power consumption to increase. The input resistance of U7 current sensing pin is much larger than 10K. Therefore the series resistor is not expected to alter the operation of U7.
Agree. I have updated that message recently, please have a look. I think it is necessary to add one more component for a special case I didn't think about. See a drawing there as well.

By the way, if the input resistance of U7 current sensing pin is much larger than 10K then almost all voltage from capacitor will be applied to U7 current sensing pin (it will be similar to a simple resistor divider), 10K resistor will not protect U7 from overvoltage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 23, 2022, 01:27:25 am
However, addition of 10K series resistor should not cause power consumption to increase. The input resistance of U7 current sensing pin is much larger than 10K. Therefore the series resistor is not expected to alter the operation of U7.
Agree. I have updated that message recently, please have a look. I think it is necessary to add one more component for a special case I didn't think about. See a drawing there as well.

By the way, if the input resistance of U7 current sensing pin is much larger than 10K then almost all voltage from capacitor will be applied to U7 current sensing pin (it will be similar to a simple resistor divider), 10K resistor will not protect U7 from overvoltage.
Yes, adding a small series resistance (100R) between the filter capacitor and the ZIF socket will reduce the instantaneous peak of the transient current to 300mA when a direct short is placed across K and A test pins.

Regarding current sensing pin of U7, it is possible this device has ESD protection, but dumping a capacitor charged to 30V directly into it would likely cause permanent damage. I accidentally destroyed the SRV05-4 protection device in a much older transistor tester (GM328 AY-AT type) with a capacitor which I (incorrectly) thought was discharged. The ATmega328 MCU was undamaged, so the protection circuit did protect the MCU. I temporarily removed the faulty SRV05-4 but will replace it as soon as the replacements arrive. I also ordered replacement U7 devices at the same time. I will be testing the revised circuit you recommend as soon as these arrive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on December 23, 2022, 06:00:23 am
Yes, adding a small series resistance (100R) between the filter capacitor and the ZIF socket will reduce the instantaneous peak of the transient current to 300mA when a direct short is placed across K and A test pins.
300mA will be applied for a very short time and will not damage the diode.
And we can increase this resistor to limit the current more. But we have to know triggering voltage for zenner diode detection to find the best value for the resistor.
Can you find this voltage?
Just remove burned u7 and connect voltage supply to K and A terminals to emulate voltage drop of zenner diode. Set 30v and slowly decrease it, TT will start detecting zenner diode at specific level. It will be near 25v most probably. Having triggering voltage we'll be able to find better value for that resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 23, 2022, 06:22:03 am
I also ordered replacement U7 devices at the same time. I will be testing the revised circuit you recommend as soon as these arrive.
For me, your efforts to restore this clone from FNIRSI look ridiculous - it's like trying to make a chocolate candy out of shit!? FNIRSI has released a crude, low-quality product to the market, which does not correspond to the level of this project in any way. It is desirable to return such products to the seller, to demand a refund of the money spent for wasting time. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 23, 2022, 08:02:01 pm
Hardware upgrade and update mod m-firmware 1.43m,k-firmware 1.13k for clone LCR-TC1! ;)
I wish I had purchased LCR-TC1 last year, back when the Asian manufacturers made them with ATmega324 MCU. Sadly it appears all LCR units available today contain an unknown MCU (frequently mislabeled ATmega328). I know of 2 ways to ID the fake MCU, but it requires seeing a photo of PC board (never shown by the Asian vendors):
   1) Pinout is totally different than Atmel MCU
   2) There is no crystal

I would have loved to do the ATmega644 mod described in detail in the following post. It has all the advanced features in a self-contained unit powered by a rechargeable battery!
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3578117/#msg3578117 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3578117/#msg3578117)

FYI the Asian vendors are now offering bare ATmega324 and ATmega644 TQFP-44 MCU chips for $20-30 USD each, plus shipping. I suspect they learned the bare IC chip all by itself can now be sold for more $ than a fully assembled transistor tester. As a long-term Atmel AVR fan I’m glad I bought several tubes of AVR MCU (DIP-40) with large flash size several years ago before they became expensive, and then unavailable from USA distributors like Digikey & Mouser.

New plan: I’ll build a “full featured” transistor tester from scratch. As a consolation prize I may use a much larger TFT display panel. It will be the “bench version” rather than “handheld.”
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 23, 2022, 08:26:03 pm
I also ordered replacement U7 devices at the same time. I will be testing the revised circuit you recommend as soon as these arrive.
…FNIRSI has released a crude, low-quality product to the market, which does not correspond to the level of this project in any way.
Maybe FNIRSI had no official relationship at all with these recent LCR-TC1 clones?
Could it be that the LCR clone makers simply thought it would look better to display FNIRSI on the self-calibration screens?

When I ordered the LCR-TC1 (where U7 failed after I used it a couple of times) I was hoping to receive the ATmega324 unit.

From what I’ve read about FNIRSI, the stuff they make is very cheap. Some of it is said to be “functional” to a certain extent. But mostly it is just “cheap.” I won’t buy any more FNIRSI gear until their reputation improves. I own way too much test gear already. Most of it is in the “restored vintage” category.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrAl on December 24, 2022, 01:39:27 pm
MrAl,why did you provide us with a full copy of the message February 23, 2013 from the 1st page of the topic? You could just make a short link to this post in the topic.

Oh it must have come out that way when quoted the very first post.  Not sure why the images show up again like that.  Makes it longer.
I can try to get rid of that part i guess.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrAl on December 24, 2022, 01:44:06 pm
Also, these little meters will never be able to read inductors except for the very small ones maybe, and maybe only air core inductors. 

The Transistortester isn't an LCR meter, but in can measure L, C and R to some extend. Get one, compare the results with a proper LCR meter, and you'll see that the Transistortester isn't that bad.
For several years I’ve been using a device known as the LC100-A to measure inductors and capacitors. I highly recommend the LC100-A for measuring small capacitance and inductance - uH and pF. That said, the LC100-A is also capable of measuring 10,000uF and 50H.

The LC100-A is a modern digital version of the legendary “grid dip meter” used by ham radio enthusiasts for nearly 100 years. It tests the unknown L or C by connecting it in parallel with an internal calibrated C or L to form a tuned LC circuit. It then uses an IC comparator with positive feedback to drive the LC circuit into steady oscillation. Typical oscillation frequency is from 5kHz to 500kHz. Finally an internal MCU-based frequency counter measures the frequency of oscillation and uses clever math to calculate and display the uH or pF of the unknown L or C.

As a result of my personal experience with the LC100-A I recommend that everyone who enjoys using their transistor tester should also try out the LC100-A.

There are numerous Asian vendors for the LC100-A. Although the quality and accuracy of the LC100-A implementation varies by vendor, the cost ( < $25 USD) allows one to explore this useful device on a budget. The original manufacturer of the LC100-A is a company named Ming-He. I have a genuine branded Ming-He LC100-A which is amazingly accurate, often within 2% when compared to high-end LCR meters. If you can find a vendor who shows a photo of the LC100-A with a Ming-He label under the PC board, then this is the one to buy.

Here is a link to a more comprehensive discussion of the LC100-A from the Antique Radio forum:

https://www.antiqueradios.com/forums/viewtopic.php?f=8&t=365161 (https://www.antiqueradios.com/forums/viewtopic.php?f=8&t=365161)


-Elecdonia


What is the excitation current adjustment range?

I cant see how any one meter will be able to measure all inductors, although it may still be useful.
For example, some buck converters will output 100ma while others 100 amps.  That means the filter inductor may be seeing either 100ma DC or 100 amps DC.  I've dealt with that entire range in my career so i can see how things can vary and how the inductance can vary.
Im not saying other meters cant help, but they will never be able to test the entire range of inductors available.  That's all.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrAl on December 24, 2022, 01:46:21 pm
Hello there,

If you get a scope and frequency generator you can test for all those things and get the error down to a very low value.  This is especially useful for cap ESR which is an important specification.
(...)
I agree with your remarks about the potential pitfalls when measuring inductors and capacitors, but the keyword is convenience: for a quick check these testers are exceptionally useful.

Yes of course i understand that, but i wanted to make it clear that no one tester can test every inductor out there and some require a large DC bias to test properly.  For a quick example, saturation current.

I just wanted to make it clear that there will be inductors that are harder to test so they would have to be tested in the actual circuit they will be used in or a prototype of the same circuit.  That way they are subject to the same bias and frequencies and all that.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 24, 2022, 01:55:42 pm
I just wanted to make it clear that there will be inductors that are harder to test so they would have to be tested in the actual circuit they will be used in or a prototype of the same circuit.  That way they are subject to the same bias and frequencies and all that.
None of the people who understand the meaning of electronics does not argue with this opinion, it's true, but as correctly observed by dear rsjsouza - the key purpose for this project is a QUICK TEST of a part, removed from the board or a new (unknown) part. For more detailed testing and analysis you will certainly need more serious equipment. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 24, 2022, 03:16:51 pm
None of the people who understand the meaning of electronics does not argue with this opinion, it's true, but as correctly observed by dear rsjsouza - the key purpose for this project is a QUICK TEST of a part, removed from the board or a new (unknown) part. For more detailed testing and analysis you will certainly need more serious equipment. :)
I agree 100%.

The transistor tester is intended to be the quickest, easiest, and lowest cost method to identify unknown components and provide reasonable measurements of their parameters. Often this is sufficient when diagnosing a malfunctioning circuit. Faulty components usually measure grossly out of spec. But a component which measures within +/- 20% of its expected value is likely to be functional.

Yes, "lab grade" test gear can be necessary for comprehensive design and debugging projects. However one doesn't always need expensive gear to quickly determine whether a component is good or bad. I own plenty of test gear, yet I nearly always make my "first tests" with small convenient easy-to-use tools like the transistor tester or a hand-held 3.5 digit multimeter. I also own a 6.5 digit multimeter ( HP 3456A ), but I don't use it every day.

Finally, for people with limited budgets and for folks who are just starting out with electronics, low-cost multi-function test gear like the transistor tester is essential.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 24, 2022, 06:01:17 pm
What is the excitation current adjustment range?

I cant see how any one meter will be able to measure all inductors, although it may still be useful.
For example, some buck converters will output 100ma while others 100 amps.  That means the filter inductor may be seeing either 100ma DC or 100 amps DC.  I've dealt with that entire range in my career so i can see how things can vary and how the inductance can vary.
Im not saying other meters cant help, but they will never be able to test the entire range of inductors available.  That's all.
I value your comments about L & C measurement and wish to continue this discussion in greater depth.
Therefore let’s move our discussion to the following topic which is focused on L/C measurement devices such as the LC100-A:

https://www.eevblog.com/forum/testgear/lc100-a-a-precise-lc-meter-for-3-75$/msg4596301/#msg4596301 (https://www.eevblog.com/forum/testgear/lc100-a-a-precise-lc-meter-for-3-75$/msg4596301/#msg4596301)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 24, 2022, 07:20:17 pm
One of the new clones of the Chinese industry and its inner world. The marking of the chips is smeared, but if we compare the location of 6 external measuring resistors, we can assume that the Chinese LGT8F328P controller or its equivalent is used. ;)
The photos are not mine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 24, 2022, 11:50:30 pm
I finally took the plunge and got a random version from eBay. From the outside this looks identical to the LCR-TC1 version but inside it has the same PCB as LCR-T7(FNIRSI) AFAICS complete with a (presumably fake) chip marked as MEGA328P. When you power it up in test mode it says FNIRSI-TC1, pauses at 38% but it does not report the firmware version at the end. I was hoping to reflash it, never mind.
I got a similar unit a couple of weeks ago. It works but... I wanted a unit with ATmega324 so I could change the MCU to ATmega644 and gain a lot more functionality in a self-contained battery-powered unit. This post describes the mod I want to do:
     $20-lcr-esr-transistor-checker-project/msg3578117 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3578117/#msg3578117)
 
But... No luck!
Yesterday I ordered another unit which just might contain the ATmega324. These things are cheap enough that I'll keep at it until I get the one I want!

FYI these forum posts suggest the fake ATmega328 is actually a APT32F172K8T6 :
     $20-lcr-esr-transistor-checker-project/msg4291063 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4291063/#msg4291063)
     $20-lcr-esr-transistor-checker-project/msg4370932 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4370932/#msg4370932)
     $20-lcr-esr-transistor-checker-project/msg4383955 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4383955/#msg4383955) 
     $20-lcr-esr-transistor-checker-project/msg4398580 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4398580/#msg4398580)
     $20-lcr-esr-transistor-checker-project/msg4429093 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4429093/#msg4429093)

Also take a look at the attached pinouts. They are totally different! In fact the VDD and VSS pins are on opposite sides of the package! The only thing they have in common is that both MCU chips are in a 32-pin TQFP package.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Spongey on December 28, 2022, 05:32:14 am
I found out two other things about the fake TC1.

It sends traffic down the serial port (which is connected to the USB port via a CH340N) at various points, such as pressing the button, making a measurement and decoding IR. Not readable text though.

Pressing the button 4 times rapidly puts in into a bootloader screen. Not managed to do anything else at that point. After 5 minutes (or disconnecting the battery) it resumes normal operation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 28, 2022, 08:33:11 pm
One of the new clones of the Chinese industry and its inner world. The marking of the chips is smeared, but if we compare the location of 6 external measuring resistors, we can assume that the Chinese LGT8F328P controller or its equivalent is used. ;)
The photos are not mine.
RE: This LGT8F328P clone of the Atmel ATmega328 MCU:
     Evidently this MCU has been ported into the Arduino IDE.
     It is also claimed that clone Arduino boards are available with this LGT8F328P MCU.
     I intend to get some for experimentation since they cost almost nothing.
     I'm intrigued by its (claimed) 32MHz clock option.

The following links may be useful:
     projects/anyone-here-interested-in-the-logic-green-avrs-lgt8f328p (https://www.eevblog.com/forum/projects/anyone-here-interested-in-the-logic-green-avrs-lgt8f328p/msg2717650/#msg2717650)
     microcontrollers/lgt8f328p-clone-of-atmega328-with-lots-of-extras-anybody-use-them (https://www.eevblog.com/forum/microcontrollers/lgt8f328p-clone-of-atmega328-with-lots-of-extras-anybody-use-them/)

Also a suggestion for searching for this MCU on EEVblog: Try both of these search terms: LGT8F328P and LG8F328 (without P at the end), and also search for "logic green" (manufacturer of the LGT8F328P)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 29, 2022, 06:58:02 pm
I found out two other things about the fake TC1. It sends traffic down the serial port (which is connected to the USB port via a CH340N) at various points, such as pressing the button, making a measurement and decoding IR. Not readable text though. Pressing the button 4 times rapidly puts in into a bootloader screen. Not managed to do anything else at that point. After 5 minutes (or disconnecting the battery) it resumes normal operation.
My LCR-TC1 FNIRSI responds to the "quickly press the button 4 times" command as seen in the attached photo. It displays FNIRSI-TC1 in the bootloader screen. It also displays FNIRSI-TC1 at the start of the selftest procedure. I haven't yet checked for any output from the USB port.

-E
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on December 30, 2022, 11:29:33 am
How does one know if this model uses genuine part? Photo shows 32 pin atmega…

ARCELI LCR-T4 ESR Meter Transistor Tester Diode Triode Capacitance SCR Inductance https://amzn.eu/d/g9qNQx6
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 30, 2022, 12:25:13 pm
It's a lottery. >:( Even when the images show a genuine ATmega it doesn't mean that you'll get one with your new tester. One of the replacement MCUs has a different pinout (check Vcc and Gnd). The other one often has fake markings with a specific batch number and production date code (was posted a while ago).
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on December 30, 2022, 01:42:57 pm
PCB in the photos has ISP header specific for atmega MCU. So, if your PCB is identical to the photo then most probably it will be atmega MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 30, 2022, 02:47:01 pm
How does one know if this model uses genuine part? Photo shows 32 pin atmega…
ARCELI LCR-T4 ESR Meter Transistor Tester Diode Triode Capacitance SCR Inductance https://amzn.eu/d/g9qNQx6
The unit in the Amazon photos has a genuine ATmega328 MCU. Because it’s coming from Amazon you can return it if it doesn’t look exactly like the photo.

One other thing: This unit does not have a protection circuit for the MCU. So be sure to discharge all capacitors before connecting them to the tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 30, 2022, 03:05:34 pm
It's a lottery. >:( Even when the images show a genuine ATmega it doesn't mean that you'll get one with your new tester.
The following post contains the most recent (16 Dec 2022) clone identification and comparison list. I think it is the best available reference to identify different versions of the transistor tester:

$20-lcr-esr-transistor-checker-project/msg4584517 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4584517/?topicseen#msg4584517)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Spongey on December 30, 2022, 04:06:34 pm
I haven't yet checked for any output from the USB port.

For that I just connected a terminal program to the virtual COM port the CH340N creates on a PC. I don't know what the serial port speed is though. A scope connected to the header near U1 could work that out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 30, 2022, 05:05:58 pm
Feliciano,this measurement operation is true for the classical tester scheme. But in the clone version with a fake processor, the LM358 operational amplifier is present in the zener diode measurement circuit.What function does it perform in the scheme? A clear and understandable schematic diagram of the clone is needed to definitively determine the cause of this error. ;)
I have a recently manufactured LCR-TC1 clone containing two LM358 opamps. I will endeavor to post a schematic of my unit. This unit employs APT32F172K8T6 MCU. I have the MCU pinout so I can show which of its I/O pins are used for zener diode test when I draw the schematic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 30, 2022, 05:42:41 pm
I also ordered replacement U7 devices at the same time. I will be testing the revised circuit you recommend as soon as these arrive.
For me, your efforts to restore this clone from FNIRSI look ridiculous - it's like trying to make a chocolate candy out of shit!? FNIRSI has released a crude, low-quality product to the market, which does not correspond to the level of this project in any way. It is desirable to return such products to the seller, to demand a refund of the money spent for wasting time. ;)
If it was from Amazon I would have returned it. But this was eBay purchase shipped direct from China. I have bought from same large Chinese eBay vendor many times with no problem. So I think I will keep it and use it for experimentation.

The build quality of its PC board is actually better than some of my older transistor tester units. The LCD display is sharp & bright. The plastic case is well designed and it looks great. Aside from failure of U7 in the 30V step-up circuit for zener diode test, this LCR-TC1 is reasonably functional. So far I observed it gives accurate results for resistors and for the uF of capacitors. I still need to make detailed tests for all other items which are identified and measured accurately by a traditional transistor tester.

RE: Zener test feature, I temporarily inserted a 10K series resistor at the output from the 30V step-up converter. This works OK while waiting for arrival of replacement U7 chips. Note: This 10K series resistor was in the very first schematics published for implementing zener diode test feature.

I think these are the main faults of transistor testers containing non-Atmel MCU:
   1) Firmware cannot be changed or upgraded
   2) Several features of the traditional transistor tester aren’t implemented
   3) 30V power source for zener testing does not have functional current limiting
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 30, 2022, 07:47:05 pm
I have said before that we will get more unpleasant surprises if we test the clones now on the new CPUs in all modes.
I carefully study the customer reviews of clone models with APT32F172K8T6 and LGT8F328 chips and can add a few more differences that are characteristic of a tester based on these chips:
1.Incorrect measurement of ESR capacitors.For most serviceable electrolytic capacitors, the ESR is not defined at all or is designated as 0.00. For some types of ceramic SMD capacitors, the ESR, on the contrary, is overestimated by 10-100 times.
2.Some faulty capacitors are detected by the tester as 2 counter diodes.
3.Some BJT transistors (for example,2N5089,MPSA12,MPSA13, etc.) are defined as thyristors or resistors.
4.Some JFET transistors (e.g. J112,J113,2N5457, etc.) are not defined at all or are defined as BJT.
5. Diode assemblies with a common cathode are incorrectly determined.
I think that this is not a complete list of differences from the original project and it will be supplemented over time. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 31, 2022, 12:30:25 am
These new MCU chips APT32F172K8T6 and LGT8F328 are likely to have totally different characteristics for their I/O pins.

As I understand it (please correct me if I’m wrong) measurements of very small resistance require direct connection of the tested component between one MCU I/O pin outputting 5V and another MCU I/O pin outputting 0V. The residual internal output resistance of these I/O pins are the reference resistors for this measurement. Not the 680R or 470k probe resistors. Evidently all flavors of Atmel AVR MCU have similar and relatively stable internal output resistance for their I/O pins. This provides capability to share similar software among all Atmel AVR MCU varieties.

I discovered a very old post which states the output resistance of an Atmel AVR I/O pin is about 20R:
     $20-lcr-esr-transistor-checker-project/msg889515 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg889515/?topicseen#msg889515)

However, other MCU are likely to have considerably different internal resistance for I/O pins set in output mode. For example some of these new MCU are said to have 80mA source or sink capability on their output pins. Their residual output resistance would be much lower than Atmel AVR.

One thing I find of interest is that both the APT32F172K8T6 and the LGT8F328 can operate with 5V power supply. Because of this their I/O pins can directly generate 5V output levels for “logic high.” Compare this to nearly every other modern MCU: Their I/O in output mode can produce only 3V3 maximum for the logic high output state. This could explain why there aren’t any transistor testers using STM32 or other similar MCU families. The capability to directly generate a 5V output from an I/O pin is essential to the traditional transistor tester architecture. Otherwise an additional driver circuit separate from the MCU itself is necessary.

I’m beginning to think about “output driver” circuits which are independent from the MCU itself. Would it be possible to design such a circuit to be both simple and precise?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on December 31, 2022, 10:04:29 am
As you say, the output current of these MCUs is limited, but also keep in mind we are often using small-battery-powered units, and most of the times we are talking about "chinese" regulators (and other components), so asking for pulses of 50mA or so can generate different kinds of troubles/errors (and quickly exhaust the battery).

Fortunately, the developers took that into consideration, and that's why the calibration procedure was introduced, which allows us to obtain a reasonable accuracy on the measurements, if we remember to calibrate the instrument every now and then, specially if you are alternating leads and ZIF measurements (for which the m-firmware offer the option to have different profiles).
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 31, 2022, 02:58:37 pm
As you say, the output current of these MCUs is limited, but also keep in mind we are often using small-battery-powered units.
The Atmel AVR MCU chips (ATmega328, ATmega324, ATmega644) share similar output current ratings from their digital I/O pins. But we know very little about the characteristics of these alternate MCU chips from the Chinese manufacturers. Some are said to offer 80mA output current. These new Chinese MCU chips are targeted at low-cost applications where BOM cost and PC board real estate is saved when the output pins can drive loads directly without needing additional components.
Quote
…and most of the times we are talking about "chinese" regulators (and other components), so asking for pulses of 50mA or so can generate different kinds of troubles/errors (and quickly exhaust the battery).
Yes, the stability of the 5.0V power supply rail is critically important for the transistor tester. This is why it is often recommended to install a higher grade LDO voltage regulator IC in place of the commonly used 78L05. Larger input and output capacitors near the voltage regulator are also recommended. I intend to make detailed measurements of the 5V rail with my oscilloscope to learn how large the variation is when the transistor tester is measuring small resistance, such as while testing capacitor ESR, and also during self-calibration.
Quote
Fortunately, the developers took that into consideration, and that's why the calibration procedure was introduced, which allows us to obtain a reasonable accuracy on the measurements, if we remember to calibrate the instrument every now and then, specially if you are alternating leads and ZIF measurements (for which the m-firmware offer the option to have different profiles).
Unfortunately the Chinese engineers who ported the traditional transistor tester software to these other (non-Atmel) MCU chips were not fully aware of these issues. They were on a tight budget for expense and development time. Therefore they released firmware which was only partially functional.

At this time my experience with non-ATmega328 transistor testers extends only to one LCR-TC1 unit containing the APT32F172K8T6 MCU. So far the only improved feature I’ve observed is that measurements finish much faster in comparison to traditional transistor testers with ATmega328 clocked at 8MHz. I estimate the speed of the LCR-TC1 to be 4 or 5 times faster.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on December 31, 2022, 04:14:28 pm
Small resistors measurement needs not more than 5v/720R=6,9mA additional current. If you want to load TTto investigate power supply stability then you should measure inductance - it takes up to 5v/38R=130mA additional current (for a short period of time of course). lgt8f328p takes even more since it has lower internal resistance of io-ports than atmega MCU has. And I know nothing about APT32F172K8T6, but inductance measurement will load it hard as well I believe.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on December 31, 2022, 05:44:16 pm
Small resistors measurement needs not more than 5v/720R=6,9mA additional current.
If I understand this correctly: Small resistor measurement includes one 680R probe resistor in series with internal resistance of two MCU output ports (one I/O port at 5V, other I/O port at 0V). Total resistance of 720R is 680R + (2 * 20R).
Quote
If you want to load TT to investigate power supply stability then you should measure inductance - it takes up to 5v/38R=130mA additional current (for a short period of time of course).
For this case there is only the internal resistance of two MCU output ports in series. Again, one I/O port is at 5V and other at 0V. The unknown inductor is connected between these 2 I/O ports.
Quote
lgt8f328p takes even more since it has lower internal resistance of io-ports than atmega MCU has. And I know nothing about APT32F172K8T6, but inductance measurement will load it hard as well I believe.
At this time I will re-read all of the TT manuals and documentation. Then I will measure the parameters of the output ports of the APT32F172K8T6 in my LCR-TC1.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on December 31, 2022, 06:12:46 pm
I would suggest you to have a look into source code of TT, it contains very nice comments where measuring methods are described. And there is a document from Karl where he describes the methods as well.
And I am not sure how can you find internal resistance of mcu's ports if you do not have developer toolchain for APT32F172K8T6 to compile and run simple tests on it (you need pull io-port up or down, connect current source to the port, measure voltage drop on the port and calculate the resistance). We do not even know how that fnirsi bootloader works...
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 31, 2022, 06:38:04 pm
If I understand this correctly: Small resistor measurement includes one 680R probe resistor in series with internal resistance of two MCU output ports (one I/O port at 5V, other I/O port at 0V). Total resistance of 720R is 680R + (2 * 20R).

Here you will find a very brief and practical explanation of how the tester works.
http://www.pa3fwm.nl/technotes/tn11b.html (http://www.pa3fwm.nl/technotes/tn11b.html)
All very clear and accessible.Very much I advise to acquaint all. This certainly does not replace the grand work done by the authors of the firmware to create detailed documentation. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on December 31, 2022, 06:46:17 pm
If I understand this correctly: Small resistor measurement includes one 680R probe resistor in series with internal resistance of two MCU output ports (one I/O port at 5V, other I/O port at 0V). Total resistance of 720R is 680R + (2 * 20R).

Here you will find a very brief and practical explanation of how the tester works.
http://www.pa3fwm.nl/technotes/tn11b.html (http://www.pa3fwm.nl/technotes/tn11b.html)
All very clear and accessible.Very much I advise to acquaint all. This certainly does not replace the grand work done by the authors of the project to create detailed documentation. :)

Also here, for those who prefer visual learning:

https://www.youtube.com/watch?v=bRtLkQ8dOj0 (https://www.youtube.com/watch?v=bRtLkQ8dOj0)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 31, 2022, 06:51:55 pm
Also here, for those who prefer visual learning:
Yes, this video is also very useful for those who want to understand in detail the principle of the tester!  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on December 31, 2022, 08:24:50 pm
Amazon UK sourced LCR-T4 product info update:

https://www.amazon.co.uk/gp/product/B07J2Q4VY9/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1 (https://www.amazon.co.uk/gp/product/B07J2Q4VY9/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1)

Note: In the event this listing is edited or removed, I have archived the Amazon page in the current (incorrect listing) state, for your records: https://web.archive.org/web/20221231203216/https://www.amazon.co.uk/gp/product/B07J2Q4VY9/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1 (https://web.archive.org/web/20221231203216/https://www.amazon.co.uk/gp/product/B07J2Q4VY9/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1)

That archived URL seems to fail ONLY when clicked here, so I added it to a "tinyurl.com" URL:
https://tinyurl.com/amaz-B07J2Q4VY9-listing (https://tinyurl.com/amaz-B07J2Q4VY9-listing)

This item arrived with the telltale signs of it being a Chinese counterfeited IC:

# No crystal
# USB-C socket
# CH-340N IC


Suffice to say I immediately went on CS chat, sent them these photos (attached and on the post immediately following this one) and they refunded without question, and allowed me to keep this product.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on December 31, 2022, 08:27:35 pm
Amazon UK sourced LCR-T4 product info update:

https://www.amazon.co.uk/gp/product/B07J2Q4VY9/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1 (https://www.amazon.co.uk/gp/product/B07J2Q4VY9/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1)

This item arrived with the telltale signs of it being a Chinese counterfeited IC:

# No crystal
# USB-C socket
# CH-340N IC

Suffice to say I immediately went on CS chat, sent them these photos (attached and on the post immediately following this one) and they refunded without question, and allowed me to keep this product.


Second photo (front) attached:
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 01, 2023, 06:55:21 am
This item arrived with the telltale signs of it being a Chinese counterfeited IC:

It's a lottery. >:( Even when the images show a genuine ATmega it doesn't mean that you'll get one with your new tester.
Madires spelled it right.Unfortunately, you could not win this lottery, like many others who want to get an authentic product from Chinese comrades.
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on January 01, 2023, 08:06:20 am
This item arrived with the telltale signs of it being a Chinese counterfeited IC:

It's a lottery. >:( Even when the images show a genuine ATmega it doesn't mean that you'll get one with your new tester.
Madires spelled it right.Unfortunately, you could not win this lottery, like many others who want to get an authentic product from Chinese comrades.

Due to the sheer size of this thread and the variety of opinions, sketchy sometimes, elsewhere online and here, would you please clarify:

# What is “wrong” with the LCR-T4 units with no crystal, a counterfeit “mega328p” and a USB-C socket

# What firmware they’re running

# Whether there is a way to mod them and flash in a special version of the original project  firmware

?

Thank you. As much detail as possible please. Happy 2023! Blessings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 01, 2023, 08:19:03 am
"# What is “wrong” with the LCR-T4 units with no crystal, a counterfeit “mega328p” and a USB-C socket"

eti,the answers to your questions are on this page in a message from elecdonia
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610050/#msg4610050 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610050/#msg4610050)
and my message below, in which I listed the detected flaws of these clones with fake chips
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/#msg4610314 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/#msg4610314)

"# What firmware they’re running"
This is a proprietary firmware from the clone manufacturer.

"# Whether there is a way to mod them and flash in a special version of the original project  firmware"
There is no such possibility yet!
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on January 01, 2023, 08:27:44 am
"# What is “wrong” with the LCR-T4 units with no crystal, a counterfeit “mega328p” and a USB-C socket"

eti,the answers to your questions are on this page in a message from elecdonia
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610050/#msg4610050 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610050/#msg4610050)
and my message below, in which I listed the detected flaws of these clones with fake chips
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/#msg4610314 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/#msg4610314)

"# What firmware they’re running"
This is a proprietary firmware from the clone manufacturer.

"# Whether there is a way to mod them and flash in a special version of the original project  firmware"
There is no such possibility yet!

I appreciate your rapid help. Okay so it’s as good as useless, got it. I’ll keep it in my “might use one day” pile. 😁
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 01, 2023, 02:53:14 pm
# What firmware they’re running

# Whether there is a way to mod them and flash in a special version of the original project  firmware

They use a modified k-firmware with a more fancy UI, but had to remove features to free up flash memory for the fancy UI. At the moment Karl-Heinz and I have no plans to support any other MCU. We have to wait and see what will happen after chipageddon is over, i.e. if ATmegas will be inexpensive and easy to source again, or not. However, a user is working on a port of the m-firmware for the Logic Green MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: py-bb on January 01, 2023, 02:59:44 pm
I haven't yet checked for any output from the USB port.

For that I just connected a terminal program to the virtual COM port the CH340N creates on a PC. I don't know what the serial port speed is though. A scope connected to the header near U1 could work that out.

When I opened my T7 up it had like 1 IC. if there is a USB->UART in there it is integrated into the main IC - in which case all you'll see is USB traffic. You wont see the baud rate from this.

That said 9600 is a good guess - do you know anything it's supposed to respond to?

"screen /dev/ttyUSB0" tends to set the baud rate to 9600 but it will do lots of non-trivial stuff for you (TTYs are a big topic) and set it up for you, this tends to abstract things like \r expected for newlines, but if you are stuck I find "echo -n -e 'WHATEVER\r' > /dev/ttyUSB0" works quite well (This is a Bashism)

 
Title: Re: $20 LCR ESR Transistor checker project
Post by: eti on January 01, 2023, 07:35:52 pm
# What firmware they’re running

# Whether there is a way to mod them and flash in a special version of the original project  firmware

They use a modified k-firmware with a more fancy UI, but had to remove features to free up flash memory for the fancy UI. At the moment Karl-Heinz and I have no plans to support any other MCU. We have to wait and see what will happen after chipageddon is over, i.e. if ATmegas will be inexpensive and easy to source again, or not. However, a user is working on a port of the m-firmware for the Logic Green MCU.

Thank you. Who is "a user" btw?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Spongey on January 01, 2023, 08:15:44 pm
When I opened my T7 up it had like 1 IC. if there is a USB->UART in there it is integrated into the main IC - in which case all you'll see is USB traffic. You wont see the baud rate from this.

That said 9600 is a good guess - do you know anything it's supposed to respond to?

Some of the fakes have a CH340N chip connected to the MCU which look like a UART from their pin description. The same pins go to a 6 pin header nearby: presumably for flashing the device. A scope on there should reveal the baud rate.

I've tried a range of speeds including 9600baud and got no consistent output and nothing like readable ASCII. Maybe it's just binary data in a proprietary format?

I've no idea what data should be sent on there: presumably only FNIRSI know. I was hoping it would output something like a version number or the value of whatever it was measuring and maybe some usable commands, nope.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 01, 2023, 10:01:33 pm
Thank you. Who is "a user" btw?

A member of this forum.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 01, 2023, 10:16:24 pm
Amazon UK sourced LCR-T4 product info update:
This item arrived with the telltale signs of it being a Chinese counterfeited IC:
     # No crystal
     # USB-C socket
     # CH-340N IC

Suffice to say I immediately went on CS chat, sent them these photos (attached and on the post immediately following this one) and they refunded without question, and allowed me to keep this product.
The MCU (U1) in the photo of this LCR-T4 PC board is NOT the Atmel ATmega328P.
I received an LCR-TC1 a few weeks ago which contains an identically (mis)labeled MCU. Evidently someone in China created a totally fake Atmel label and is applying it to this other MCU chip: APT32F172K8T6. The only thing in common between the ATmega328P and the APT32F172K8T6 is they are both housed in 32-pin TQFP packages.
(Personally I find deliberate mislabeling of electronic components to be extremely annoying and insulting. It is bad enough when the original label has been removed with sandpaper >:()

Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 01, 2023, 10:34:58 pm
JLCPCB lists the APT32F172K8T6 MCU in their catalog:
 
    https://jlcpcb.com/partdetail/Aptchip-APT32F172K8T6/C448572 (https://jlcpcb.com/partdetail/Aptchip-APT32F172K8T6/C448572)

They even offer a downloadable .pdf data sheet… but only in Chinese language. I don’t know much about JLCPCB, never ordered PC boards from them (yet). They do run a lot of banner ads here on EEVblog.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ozkarah on January 03, 2023, 10:21:33 pm
Hi guys,

I bought an ESR02PRO.
1- How can I check the current firmware it has now?
2- Which fw is the latest compatible for the upgrade?

thanks...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 04, 2023, 02:48:18 pm
Usually the testers display the firmware version after powering on. If not, someone has removed it on purpose. You can update to the lastest k (1.13k) or m-firmware (1.48m).
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 10, 2023, 01:03:14 am
Hello
Got 2 LCR Testers today from AliXpress..  New LCR-T4 and LCR-T7 Color 
Both have new firmware version 3.12K 
Does anybody know where to find this firmware.. or is it a hoax..  mean Chinese Variants.. ?
tnx for info.  JP
Could I ask you to please post photos of the PC boards of these LCR-T4 and LCR-T7 units which you received in December?

     I wish to determine whether any Chinese suppliers still use Atmel ATmega324 MCU.
ATmega324 has 44 pins (11 pins on each side of TQFP package).
No other MCU used in Transistor Testers has 44 pins except Atmel ATmega644.
There is a DIY upgrade which replaces original ATmega324 with ATmega644. Official OSHW Transistor Tester firmware for ATmega644 is available. This link describes the upgrade:
     https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3578117/#msg3578117
 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg3578117/#msg3578117)
However, starting in 2022 the Chinese suppliers are also using two different non-Atmel MCU which have 32 pins (8 pins per side): One type is APT32F172K8T6. Other is LGT8F328P. Evidently most of the LCR-TC1, LCR-TC2, and LC-T7 units sold since July 2022 contain these. Unfortunately there is no official OSHW Transistor Tester firmware for these recently manufactured units with non-Atmel MCU. Their firmware cannot be upgraded. Also these units lack several popular Transistor Tester features which were omitted by the Chinese suppliers.

Summary:
     ATmega324 MCU: 44-pin TQFP package. Fully supported by official OSHW Transistor Tester software. DIY upgrade to ATmega644 or ATmega1284 is possible.

     Alternate Chinese MCU, APT32F172K8T6 or LGT8F328P: 32-pin TQFP package. Software cannot be upgraded. Not supported by the OSHW Transistor Tester project.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on January 10, 2023, 11:06:19 am

Summary:
     ATmega324 MCU: 44-pin TQFP package. Fully supported by official OSHW Transistor Tester software. DIY upgrade to ATmega644 is possible.

     Alternate Chinese MCU, APT32F172K8T6 or LGT8F328P: 32-pin TQFP package. Software cannot be upgraded. Not supported by the OSHW Transistor Tester project.

... DIY upgrade to ATmega1284 is also possible:
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 11, 2023, 03:14:14 am
Summary:
     ATmega324 MCU: 44-pin TQFP package. Fully supported by official OSHW Transistor Tester software. DIY upgrade to ATmega644 is possible.
     Alternate Chinese MCU, APT32F172K8T6 or LGT8F328P: 32-pin TQFP package. Software cannot be upgraded. Not supported by the OSHW Transistor Tester project.
... DIY upgrade to ATmega1284 is also possible:
Lovely upgrade there! I forgot to mention the mega1284. I shall edit my post to include it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 11, 2023, 12:32:14 pm
Hope you guys can help me fix my T-4. I managed to break the LCD screen, so I bought a replacement off of aliexpress, but it's not working. Is this the right way to solder it, please?
Also attached a pic showing what it does when I power it up.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 11, 2023, 03:41:14 pm
Hope you guys can help me fix my T-4. I managed to break the LCD screen, so I bought a replacement off of aliexpress, but it's not working. Is this the right way to solder it, please? Also attached a pic showing what it does when I power it up.
Could you post photos of your old broken LCD screen for comparison?
Do the flat flex PC cables look exactly the same for both old and new screens?
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 11, 2023, 05:26:13 pm
Hope you guys can help me fix my T-4. I managed to break the LCD screen, so I bought a replacement off of aliexpress, but it's not working. Is this the right way to solder it, please? Also attached a pic showing what it does when I power it up.
Could you post photos of your old broken LCD screen for comparison?
Do the flat flex PC cables look exactly the same for both old and new screens?

Thanks. They look the same to me, have a look:

EDIT: I should say the pads in the pcb were intact, and the new screen looks good as well. It also seems to be properly aligned, since when I fold it in position, both lugs at the bottom of the screen line up with the holes in the pcb

EDIT2: Tried re-flashing the firmware, still the same gibberish onscreen
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 11, 2023, 06:08:32 pm
They look the same to me, have a look:
And now take a close look and compare how the cable should be soldered on the same clone as yours.
You turned the cable over. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 11, 2023, 06:25:41 pm
They look the same to me, have a look:
And now take a close look and compare how the cable should be soldered on the same clone as yours.
You turned the cable over. ;)

WTF? I reversed the cable orientation (and I don't know how a would mount it that way) and it works, but the text is all flipped horizontally. What gives? Was the screen not properly assembled or something?
I'll try to get a picture, but I need extra hands for that
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 11, 2023, 06:29:51 pm
What gives? Was the screen not properly assembled or something?
The most important thing is that you do not damage the display cable.If there is a picture on the display, but it is mirrored, all this can be fixed with another firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 11, 2023, 06:37:25 pm
What gives? Was the screen not properly assembled or something?
The most important thing is that you do not damage the display cable.If there is a picture on the display, but it is mirrored, all this can be fixed with another firmware.

That's just one issue. With the flex cable in that orientation, I can't fold it in place on top of the pcb, or it would end sitting bottom up.
Did I buy the wrong screen or something?
Here's a pic:

EDIT: Something else seems wonky. Now I need to keep the button pressed, or else the screen goes blank
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 11, 2023, 06:40:42 pm
Did I buy the wrong screen or something?
Yes, this display is working, but it is different from the one that was damaged.

EDIT: Something else seems wonky. Now I need to keep the button pressed, or else the screen goes blank
You need to connect the backlight LED to avoid this effect
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 11, 2023, 06:47:58 pm
Did I buy the wrong screen or something?
Yes, this display is working, but it is different from the one that was damaged.

EDIT: Something else seems wonky. Now I need to keep the button pressed, or else the screen goes blank
You need to connect the backlight LED to avoid this effect

OK, thanks again. I think I'm going to get me a new meter and be done with it. Damn it...
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 11, 2023, 08:47:18 pm
OK, I've decided to try and flash a modified version of the firmware to fix the orientation of the text, then I'll run wires from the pcb to the flex cable and fix that in place with hot glue.

Is this the part of the code in lcd-routines.c that needs tweaking to mirror the display?

Code: [Select]
volume = eeprom_read_byte(&EE_Volume_Value); // read Vop
   lcd_command(CMD_SET_VOP_UPPER | ((volume >> 5) & 0x07)); // set upper Vop
   lcd_command(CMD_SET_VOP_LOWER | (volume & 0x1f)); // set lower Vop
   lcd_command(CMD_SET_START_LINE | (LCD_ST7565_Y_START & 0x3f));       // Set the Start line 0
   lcd_command(CMD_SET_ALLPTS_NORMAL); // 0xa4 set display to normal
   lcd_command(CMD_SET_POWER_CONTROL | 4); // 0x28|4 Charge Pump ON
   lcd_command(CMD_SET_COM_REVERSE); // 0xc8
   lcd_command(CMD_SET_COM_NORMAL); // 0xc0 set normal Y orientation
   lcd_command(0xa1); // set MX, X orientation, is pad selectet!
   lcd_command(0xaa); // set horizontal mode
   lcd_command(0xac); // set initial row
   lcd_command(0x08); // initial row = 8  (0-7)
   lcd_clear();
   lcd_command(CMD_DISPLAY_ON); // 0xaf Display on
   lcd_set_cursor(0,0);
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 11, 2023, 09:46:24 pm
I already have WinAVR installed, and it seems to compile the code and generate the hex and eep files just fine. I guess I just need to figure out how to mirror the screen, and I also need to flip the screen 180º. Or I think so.

Using this repo for the source, not sure if that's the right one. Any pointers are appreciated.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 12, 2023, 02:04:23 am
They look the same to me, have a look:
And now take a close look and compare how the cable should be soldered on the same clone as yours. You turned the cable over. ;)
WTF? I reversed the cable orientation (and I don't know how a would mount it that way) and it works, but the text is all flipped horizontally. What gives? Was the screen not properly assembled or something? I'll try to get a picture, but I need extra hands for that
This same type of thing has happened to me: Although frustrating and time consuming, I prefer to think of these events as “learning experiences.” One new habit I’ve developed is to take plenty of photos before and during the disassembly process.
Also not every LCD screen of similar dimensions and specs has its flex cable oriented the same way. I’ve run into this myself.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 12, 2023, 06:59:47 am
OK, I've decided to try and flash a modified version of the firmware to fix the orientation of the text, then I'll run wires from the pcb to the flex cable and fix that in place with hot glue.
Is this the part of the code in lcd-routines.c that needs tweaking to mirror the display?

No, you don't need to delve so deeply into the code to correct the orientation of the image.
All the necessary settings that you need to configure are in the Makefile file from the folder "mega328_T4_v2_st7565":

# If LCD_ST7565 option is set to 1: Flip the display's horizontal direction.
#CFLAGS += -DLCD_ST7565_H_FLIP=1
# With LCD_ST7565_H_OFFSET you can specify a horizontal pixel offset to the display window.
# The controller knows 132 horizontal pixel, the window shows only 128 pixel.
# OFFSET values can vary for the connected display type to 0, 2 or 4.
CFLAGS += -DLCD_ST7565_H_OFFSET=0
# If LCD_ST7565 option is set to 1: Flip the display's vertical direction
#CFLAGS += -DLCD_ST7565_V_FLIP=1
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 12, 2023, 07:43:38 am
This same type of thing has happened to me: Although frustrating and time consuming, I prefer to think of these events as “learning experiences.” One new habit I’ve developed is to take plenty of photos before and during the disassembly process.
Also not every LCD screen of similar dimensions and specs has its flex cable oriented the same way. I’ve run into this myself.

You're 100% right. I'll be more disciplined from now on.

No, you don't need to delve so deeply into the code to correct the orientation of the image.
All the necessary settings that you need to configure are in the Makefile file from the folder "mega328_T4_v2_st7565":

# If LCD_ST7565 option is set to 1: Flip the display's horizontal direction.
#CFLAGS += -DLCD_ST7565_H_FLIP=1
# With LCD_ST7565_H_OFFSET you can specify a horizontal pixel offset to the display window.
# The controller knows 132 horizontal pixel, the window shows only 128 pixel.
# OFFSET values can vary for the connected display type to 0, 2 or 4.
CFLAGS += -DLCD_ST7565_H_OFFSET=0
# If LCD_ST7565 option is set to 1: Flip the display's vertical direction
#CFLAGS += -DLCD_ST7565_V_FLIP=1

Awesome! Thanks, I'll try that. Technically I just need to flip the display horizontally. The screen will be upside down, but I can always flip the whole device and use it that way, not a huge deal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrSqueaky on January 12, 2023, 07:58:52 am
I received an LCR-TC2 from Aliexpress that I ordered in December 2022. The board appears to be updated. The boot screen says firmware is 3.1E and chip U3 seems to have been removed. No options for changing the power off delay (which is annoying short).

I previously had a round GM328A but the display driver was glitchy and wouldn't initialise properly half of the time. I managed to smash the display and couldn't easily source a replacement (I think it is a Samsung E1310/E1360/E1360M/B210/B220/B510 copy)
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 12, 2023, 08:31:09 am
OK, I've decided to try and flash a modified version of the firmware to fix the orientation of the text, then I'll run wires from the pcb to the flex cable and fix that in place with hot glue.
Is this the part of the code in lcd-routines.c that needs tweaking to mirror the display?

No, you don't need to delve so deeply into the code to correct the orientation of the image.
All the necessary settings that you need to configure are in the Makefile file from the folder "mega328_T4_v2_st7565":

# If LCD_ST7565 option is set to 1: Flip the display's horizontal direction.
#CFLAGS += -DLCD_ST7565_H_FLIP=1
# With LCD_ST7565_H_OFFSET you can specify a horizontal pixel offset to the display window.
# The controller knows 132 horizontal pixel, the window shows only 128 pixel.
# OFFSET values can vary for the connected display type to 0, 2 or 4.
CFLAGS += -DLCD_ST7565_H_OFFSET=0
# If LCD_ST7565 option is set to 1: Flip the display's vertical direction
#CFLAGS += -DLCD_ST7565_V_FLIP=1

One more question, please. Is this the right repo? https://github.com/Mikrocontroller-net/transistortester
There hasn't been a commit there in one year
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 12, 2023, 08:38:43 am
https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk
Here is the current actual k-firmware distribution 07.10.2021
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 12, 2023, 08:40:42 am
https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk
Here is the current actual k-firmware distribution 07.10.2021

Great, thanks. That's the one I was using  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 12, 2023, 08:54:02 am
Success! Thanks everyone for the help
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2023, 10:55:29 am
One more question, please. Is this the right repo? https://github.com/Mikrocontroller-net/transistortester
There hasn't been a commit there in one year

That's outdated (migration of mikrocontroller.net's SVN). Please use https://github.com/kubi48/TransistorTester-source!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 12, 2023, 11:12:17 am
I received an LCR-TC2 from Aliexpress that I ordered in December 2022. The board appears to be updated. The boot screen says firmware is 3.1E and chip U3 seems to have been removed. No options for changing the power off delay (which is annoying short).

Haven't seen any schematics for that version yet, but without the additional control MCU it should be easier to upgrade to an OSHW firmware. And you could customize the user interface settings to your liking.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 12, 2023, 02:31:08 pm
One more question, please. Is this the right repo? https://github.com/Mikrocontroller-net/transistortester
There hasn't been a commit there in one year

That's outdated (migration of mikrocontroller.net's SVN). Please use https://github.com/kubi48/TransistorTester-source!

Thanks. I was having issues with the calibration process, so I will use that instead  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 12, 2023, 06:45:27 pm
I was having issues with the calibration process, so I will use that instead.
With Transistor Testers that were previously in use, I go into the menu and select “Self Test” which works its way through several different screens, first with “probes shorted,” then with “probes isolated,” and finally with a film capacitor connected to pins 1-3. I use a 1.0uF capacitor for this. Don’t rush it by pressing the button to move on to the next screen. It will advance all by itself after each section finishes. I had to practice this several times before I was patient enough to wait and let it proceed at its own pace.

In particular it appears that capacitor ESR results are more accurate after performing this full menu-driven “self test” with the 1.0uF film capacitor connected to 1-3 when the display message calls for it.

I’ve also used the faster self-test with probes shorted before pressing power button. But this “fast self-test” by itself didn’t permanently shut off the “not calibrated” message. It was only after the longer self-test (from the menu) that the “not calibrated” message disappeared permanently.

I discovered this “not calibrated” issue with an unmodified “GM328 color-kit” tester running the original Chinese factory firmware it came with. This firmware displays “1.12k” but I suspect the Chinese modified it. Unfortunately its ATmega328P is locked.

Among several transistor testers in my workshop I use this one the most. I’ve had only one issue with it: I accidentally toasted its SRV05-4 overvoltage protector with a charged capacitor. The tester worked well again after removing the failed SRV05-4 except it began showing the “not calibrated” message. I observed no damage to the ATmega328P or any other parts. But I did need to run the full menu-driven self test after that incident in order to clear the “not calibrated” condition.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 12, 2023, 06:57:44 pm
I received an LCR-TC2 from Aliexpress that I ordered in December 2022. The board appears to be updated. The boot screen says firmware is 3.1E and chip U3 seems to have been removed. No options for changing the power off delay (which is annoying short).
Haven't seen any schematics for that version yet, but without the additional control MCU it should be easier to upgrade to an OSHW firmware. And you could customize the user interface settings to your liking.
I’ve been trying to get my hands on one of these for 2 months. The first unit I received, labeled LCR-TC1, contained APT32F172K8T6 MCU. The 2nd unit, also labeled LCR-TC1, contained LGT8F328P MCU. I’m now awaiting unit #3, said to be model LCR-TC2.

My goal is to acquire a unit containing Atmel ATmega324 which I will then upgrade to ATmega644 along with adding the paddle switch on the side for menu access.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 12, 2023, 07:24:53 pm
Quote from: Atmega644 datasheet
Note: 1. For all fuses “1” means unprogrammed while “0” means programmed.
With it programmed with 0xFF it sets all bits to "1" meaning unprogrammed, this means that the oscillator has a limited frequency range of 8 to 16MHz and startup mode: "slowly rising power" this is a low power operation mode for the crystal oscillator.
With it programmed with 0xF7 instead the CKSEL3 bit is progammed and this means that the crystal oscillator has a frequency range of 0.4 to 20MHz with the same starup mode as before, this is a higher power mode for the crystal oscillator.
I have an unmodified GM328A+ Transistor Tester, factory original v1.12k firmware, 8MHz, which fails to initialize its ST7565 monochrome LCD at startup when the room temperature is cold (10-15 C). But it starts up perfectly if I warm up the ATmega328 by holding my thumb over it for 20 seconds. This tester always works perfectly at normal room temperature. I plan to check the fuse bits to learn which oscillator settings are in it. Perhaps “low-power oscillator” mode starts up too slowly at very cold room temperature?

I own several Transistor Testers. The others work well at low temperatures. I’ll post what I find when I check this GM328A+ unit. I also intend to update it to current v1.13k.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on January 12, 2023, 11:06:30 pm
IIRC "low power" xristal oscillator runs at 3.3V, and the "normal" or "full swing"are 5V. The ctesters I've seen have used normal oscillators, so I set the fuses accordingly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 13, 2023, 04:23:02 am
Hello. Got 2 LCR Testers today from AliXpress..  New LCR-T4 and LCR-T7 Color. Both have new firmware version 3.12K 
Does anybody know where to find this firmware.. or is it a hoax..  mean Chinese Variants.. ? tnx for info JP
Would it be possible for forum members who recently purchased LCR- series Transistor Testers to post photos of their PC boards?

I’m asking because the Chinese manufacturers are now using 3 different MCU chips in current production LCR series Transistor Testers. Only one of these MCU chips is compatible with existing open-source -k or -m software. The other two MCU chips can use only proprietary software created by their Chinese manufacturers. That software cannot be updated or replaced by open-source Transistor Tester software.

At this time we can only determine which MCU is inside an LCR series Transistor tester by viewing a photo of the PC board. The model number, which could be LCR-TC1, LCR-TC2, LCR-T4, or LCR-T7, reveals nothing about what is inside. Often the vendors don’t even know what they are selling. They don’t post photos of the PC boards either.

Forum user indman maintains a table of clone versions of Transistor Tester hardware here:
     https://yadi.sk/d/yW8xa5NJgUo5z (https://yadi.sk/d/yW8xa5NJgUo5z)
The file name is TableClonesEn.pdf (or TableClonesRu.pdf)
However the large number of different Transistor Testers recently manufactured in China is on the verge of becoming a tsunami of randomness. Well-known model names such as LCR-TC1 or LCR-T4 are being applied to several entirely different hardware/software combinations. Some are incapable of running open-source -k and -m software. But the vendors don’t disclose this.

I recommend we should all pitch in and assist with separating the good and bad from the ugly. Photos of the PC boards will be a big help,
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrSqueaky on January 13, 2023, 12:06:54 pm
I received an LCR-TC2 from Aliexpress that I ordered in December 2022. The board appears to be updated. The boot screen says firmware is 3.1E and chip U3 seems to have been removed. No options for changing the power off delay (which is annoying short).

Haven't seen any schematics for that version yet, but without the additional control MCU it should be easier to upgrade to an OSHW firmware. And you could customize the user interface settings to your liking.

I've made a schematic the for LCR-TC2 T7-PLUS v1.2 I received. I also traced the tracks on the PCB in case I've made a mistake somewhere in the schematic. Ordered from this seller https://www.aliexpress.com/item/1005004717377243.html (https://www.aliexpress.com/item/1005004717377243.html) . I soldered on the battery connector. Hope this helps.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 13, 2023, 12:16:47 pm
IIRC "low power" xristal oscillator runs at 3.3V, and the "normal" or "full swing"are 5V. The ctesters I've seen have used normal oscillators, so I set the fuses accordingly.

low power oscillator:
- reduced voltage swing (no voltage given)
- can't drive other clock inputs
- more susceptible to noise
- low power consumption

full swing oscillator:
- rail-to-rail swing
- can drive other clock inputs
- less susceptible to noise
- power consumption higher than for low power oscillator
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 13, 2023, 12:35:46 pm
[I've made a schematic the for LCR-TC2 T7-PLUS v1.2 I received. I also traced the tracks on the PCB in case I've made a mistake somewhere in the schematic.

Matches nearly the pin assignment of the TC1 (just without the additional control MCU). PD1 and PD2 are swapped (push button and power control) and the display pinout could be:
Code: [Select]
/RES   PB4
D/C    PB5
SCL    PB7
SDA    PB6
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 13, 2023, 12:41:15 pm
PD1 and PD2 are swapped (push button and power control) and the display pinout could be:

Madires, for this clone variant your m-firmware as well as k-firmware(if ATMega644) is suitable.You only need to swap PD1 and PD2 in places. This has already been tested.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 13, 2023, 01:42:54 pm
Great! I'll add that one to the list of clone settings (Clones file).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 13, 2023, 04:41:27 pm
Madires,I am afraid that your Clones file may increase in size in an incredible way, given the number of different modifications that the Chinese industry produces! :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 13, 2023, 06:35:38 pm
Madires,I am afraid that your Clones file may increase in size in an incredible way, given the number of different modifications that the Chinese industry produces! :-DD
Wow! It will require much time and effort to categorize so many different versions.

          At first glance I suspect all 6 PC boards in these photos have either
          Atmel ATmega324 or ATmega644 MCU for the following reasons:
1) All MCU seen in these photos have 44 pins.
2) Also all of these PC boards have a place to mount the 6-pin Atmel ISP programming header. This 6-pin ISP interface is unique to Atmel products. To the best of my knowledge it isn’t used by any other MCU manufacturer.

          In contrast:
1) All non-Atmel MCU I’ve observed in Transistor Testers have only 32 pins.
2) In addition the non-Atmel Transistor Testers do not have the Atmel 6-pin ISP header. Instead they have other types of programming interface, such as SWD (single wire debug) or CH340X USB IC
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 13, 2023, 06:49:13 pm
elecdonia, I wanted to show exactly the varieties of seemingly the same topology of a printed circuit board with ATMEL MCU. To this gallery, you can add a variant with an ATMEL MCU in a DIP case.As for the variants with non-ATMEL MCU, they will make the same large gallery.  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2023, 10:22:07 am
Madires,I am afraid that your Clones file may increase in size in an incredible way, given the number of different modifications that the Chinese industry produces! :-DD

Indeed! However, one has to do what one has to do. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 14, 2023, 04:32:13 pm
Details about MCU chips found in recent production Transistor Testers:

Atmel ATmega324 has been used in Transistor Testers for several years, but recently had a big price increase ($5-15 USD) and became harder to get. This MCU has 44 pins (11 pins on each of the 4 sides). ATmega324 is supported by existing -m (Markus) Transistor Tester software. However, ATmega324 software is not available in -k (Karl-Heinz) version.

Atmel ATmega644 has same 44-pin package as ATmega324 and can be used with same PC board layout. ATmega644 has 64k flash memory compared to 32k for ATmega324. Therefore ATmega644 accommodates larger software with additional testing/measurement capability, higher resolution display fonts, and multiple user-selected languages. ATmega644 is supported by both -k and -m Transistor Tester software versions.

LGT8F328P - First used by Transistor Tester manufacturers in 2021. Price: < $1 USD. 32-pin package (8 pins on each of the 4 sides). This is same package as Atmel ATmega328. It is said to be “similar” to Atmel ATmega328. However its pinout is different and it has several additional features. For example the LGT8F328P can operate at 32MHz. The LGT8F328P has been ported into the Arduino IDE. Clone versions of Arduino Pro and Nano boards containing LGT8F328P are available. But no open-source Transistor Tester software for LGT8F328P has been officially released yet. However, one Transistor Tester enthusiast has a GitHub project to adapt the -m software to LGT8F328P:
     https://github.com/DurandA/transistor-tester-lgt328p (https://github.com/DurandA/transistor-tester-lgt328p)

APT32F172K8T6 - First used by Transistor Tester manufacturers in 2022. Also < $1 USD. 32-pin package (8 pins on each of the 4 sides). Pinout, internal architecture, and instruction set are totally different than Atmel ATmega328. Only similarity is 32-pin package. Very few development tools are available for compiling and debugging APT32F172K8T6 software. Existing open-source Transistor Tester software does not support this MCU. Warning: Unfortunately some Transistor Tester manufacturers are deliberately mis-labeling the APT32F172K8T6 as Atmel ATmega328P.
 
Conclusion:
ATmega324 and ATmega644 are the only 44-pin MCU chips found in Transistor Testers.
Therefore a quick look at the PC board will distinguish these MCU chips from the other two.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 14, 2023, 04:53:54 pm
Atmel ATmega324 has been used in Transistor Testers for several years, but recently had a big price increase ($5-15 USD) and became harder to get. This MCU is in a 4-sided TQFP package with 44 pins, 11 pins on each of the 4 sides. This MCU is fully compatible with existing -k and -m Transistor Tester software.
No.There is an m324p MCU in the k-firmware makefile, but the firmware compilation ends with an error.That is,in fact, ATmega324 is not yet supported by Karl-Heinz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2023, 06:36:16 pm
Could you please post the error message? I remember that my avr-gcc package came with a broken iom324p.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 14, 2023, 06:47:25 pm
madires,Karl-Heinz has not been answering my questions lately. Check out its current documentation - ATMega324 is not listed in the list of supported MCUs. I provide a screenshot of the error
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 14, 2023, 06:55:06 pm
No.There is an m324p MCU in the k-firmware makefile, but the firmware compilation ends with an error.That is,in fact, ATmega324 is not yet supported by Karl-Heinz.
Thank you for correcting me. I have just confirmed this:
          https://github.com/kubi48/TransistorTester-source (https://github.com/kubi48/TransistorTester-source)
contains compiled ready-to-load -k firmware for ATmega644 only. But nothing for ATmega324. I will edit my post.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 14, 2023, 06:59:57 pm
Is there any functional -k software for ATmega644 at this time?
I didn't quite understand your question?For ATmega644, there have been working k-firmware for LCR-TC1(T7),Hiland644,LCD2004 for a long time
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2023, 07:17:20 pm
I provide a screenshot of the error

The MCU type is missing. Edit setup.mk, copy the section for m328p, change 'ifeq ($(PARTNO),m328p)' to 'ifeq ($(PARTNO),m324p)', and 'MCU = atmega328p' to 'MCU = atmega324p'.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 14, 2023, 07:35:23 pm
Is there any functional -k software for ATmega644 at this time?
I didn't quite understand your question?For ATmega644, there have been working k-firmware for LCR-TC1(T7),Hiland644,LCD2004 for a long time
Karl-Heinz firmware for LCR-TC1 with ATmega644 MCU is in Yandex repository:
     https://disk.yandex.ru/d/yW8xa5NJgUo5z/LCR-%D0%A2%D0%A11/Firmware/Karl-Heinz%20K%C3%BCbbeler/English/16Mhz (https://disk.yandex.ru/d/yW8xa5NJgUo5z/LCR-%D0%A2%D0%A11/Firmware/Karl-Heinz%20K%C3%BCbbeler/English/16Mhz)

Yandex repository also mentions this recently modified Karl-Heinz ATmega644 firmware for LCR-TC1, -TC2 -T7:
     https://disk.yandex.ru/d/yW8xa5NJgUo5z/LCR-TC2/Firmware/Karl-Heinz%20Kubeller/English/FirmwareModNew (https://disk.yandex.ru/d/yW8xa5NJgUo5z/LCR-TC2/Firmware/Karl-Heinz%20Kubeller/English/FirmwareModNew)
Additional details in forum post #8001:
      https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4578967/?topicseen#msg4578967 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4578967/?topicseen#msg4578967)

Please confirm. I am hoping to obtain LCR-TC2 containing ATmega644 soon. Or if I get one with ATmega324 I will replace MCU with ATmega644. Then I will install this firmware described in forum post #8001
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 14, 2023, 07:36:45 pm
madires, it works, thanks a lot!  :-+ I will still check the firmware on any device with ATMega324, but I am sure that it will work fine. Really, this issue was solved so easily and simply.I'm sorry I didn't figure it out sooner.I think you will be able to pass this amendment to Karl-Heinz so that he adds it to his distribution?  :)

elecdonia,I think you may back edit your post regarding ATmega324 and its support in k-firmware. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 14, 2023, 08:09:12 pm
madires, it works, thanks a lot!  :-+ I will still check the firmware on any device with ATMega324, but I am sure that it will work fine. Really, this issue was solved so easily and simply.I'm sorry I didn't figure it out sooner.I think you will be able to pass this amendment to Karl-Heinz so that he adds it to his distribution?  :)
elecdonia,I think you may back edit your post regarding ATmega324 and its support in k-firmware. ;)
Many thanks to both of you!  :-+

I am always happy to see compiler finish its work with zero errors!
It just fits into flash size of ATmega324.

I am very eager to get LCR-TC2 containing either ATmega324 or ATmega644. So far I received one unit with LGT8F328P and another with APT32F172K8T6. Both were stated to be LCR-TC1 by ebay vendor. Unfortunately when I ordered those two units I did not think LCR-TC1 and LCR-TC2 were different from each other. So a week ago I ordered a third unit described by vendor as LCR-TC2. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 14, 2023, 08:13:19 pm
So a week ago I ordered a third unit described by vendor as LCR-TC2.
I think and wish you that your 3rd order attempt was a success! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 15, 2023, 04:26:45 pm
madires,what does the name of the folder "experimentelle mega328_FA-BT2" in k-firmware imply?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 15, 2023, 04:57:06 pm
That's a tester kit sold by a German ham radio magazine (kit not sold anymore). You can find some pictures at http://dk8jg.de/ttest.htm. (http://dk8jg.de/ttest.htm.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 15, 2023, 05:03:41 pm
Wow! A rare copy of 10.2013.Beautiful!  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: techie on January 15, 2023, 05:26:49 pm
Hi,

I was able to configure ComponentTester-1.48m firmware to work properly on a new LCR-TC2 v1.2 (T7 Plus v1.2 PCB) meter. Please see attached photo.
It lacks the STC15L104W chip found in the v1.0 and v1.1 PCBs, has a larger atmega644 MCU, and it swaps the test button and power enable pins.
In order to support 32x39 symbols, a minor edit to ST7735.c was required:

The line:
#include "symbols_32x39_hf.h"

should be added after:
#include "symbols_32x32_old_hf.h"

I've attached Markus v1.48m firmware binaries, along with the modified source files (colors.h, Makefile, config.h, config_644.h, and ST7735.c) needed for re-compiling  :-/O:

Hope this helps!
Title: Re: $20 LCR ESR Transistor checker project
Post by: RoGeorge on January 17, 2023, 04:44:13 pm
I have this one with a firmware from around 2015, MTester V2.07, should I bother updating its firmware?
If yes, where from please, so to be compatible with this hardware version from 91make taobao?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 17, 2023, 07:16:12 pm
That one seems to be a T4. For k-firmware try mega328_T3_T4_st7565 or mega328_T4_v2_st7565, and for m-firmware see Clones file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RoGeorge on January 17, 2023, 08:07:13 pm
Thank you.  Mine seems to be the LCR-T4 version, by looking at the pics here: https://www.mikrocontroller.net/topic/transistortester-avr?goto=4120737#4105488 (https://www.mikrocontroller.net/topic/transistortester-avr?goto=4120737#4105488)

On the previous page it says the current repository has now changed to kubi48, i.e.
https://github.com/kubi48/TransistorTester-source/tree/master/trunk/mega328_T4_v2_st7565 (https://github.com/kubi48/TransistorTester-source/tree/master/trunk/mega328_T4_v2_st7565)

1. There are countless forks on github.  Which one should I use?
2. Can not find any log for what has changed from one firmware version to the other.  Is it worth to upgrade the firmware from 2015 to the most recent one?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 17, 2023, 08:52:28 pm
Karl-Heinz' repo (k-firmware) is https://github.com/kubi48/TransistorTester-source. Your tester runs a modified k-firmware, and AFAIK there's no recent changelog. However, the k-firmware version of 2015 should be 1.10k or 1.11k (latest one is 1.13k).
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 19, 2023, 05:11:29 pm
I'm back with a question, please. A friend of mine is testing jfets with a TC1, and I have the suspicion that his measurements are not Idss and Vgsoff. Here's a picture

I perused the manual, and it seems to me that's not really Idss and Vgsoff, is that correct? Could it be that his firmware was compiled with the FET_Idss flag disabled?
Are those values shown there the ones obtained with a 680 ohms source resistor, as per the manual?
My T4 with the latest firmware does seem to measure Idss and Vgsoff, plus an extra operating point in the middle. Did I get it right and that's what it's doing?

Actually, I have two questions. I also have a few MMBFJ201 and MMBF5457, and they are both detected as BJT's by my T4, while his TC1 does spit out a reading, what's the deal there, please?

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 19, 2023, 05:24:47 pm
dazz
1. Please make the resolution of your photos smaller, attach them to the message or hide them under the spoiler. See how other forum members attach photos.
2. Install m-firmware for your T4 clone and test your transistors again.Compare your results with k-firmware. :)
3. Carefully calibrate your tester according to the author's manual.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 19, 2023, 05:49:57 pm
dazz
1. Please make the resolution of your photos smaller, attach them to the message or hide them under the spoiler. See how other forum members attach photos.
2. Install m-firmware for your T4 clone and test your transistors again.Compare your results with k-firmware. :)
3. Carefully calibrate your tester according to the author's manual.

1. Sorry about that, fixed now.
2. I believe my T4 is at the latest version and it's calibrated. Got it from Kubi40's github repo a couple weeks ago. Is madires' the m-firmware you're referring to? Should I expect different results with that one?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 19, 2023, 05:54:46 pm
2. I believe my T4 is at the latest version and it's calibrated. Got it from Kubi40's github repo a couple weeks ago. Is madires' the m-firmware you're referring to? Should I expect different results with that one?
It is likely that there will be other results, which is why I suggested that you try the madires m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 19, 2023, 05:58:54 pm
The TC1 shows just V_GS (and the corresponding current) with the JFET's gate pulled down via the 470k test resistor. Yes, the 680 Ohms resistor is used as current shunt. Can't say much more about the TC1's firmware as it is a modified k-firmware (fancy UI, less features, no source available). Your T4 shows I_DSS, V_GS with gate pulled down via 470k (plus current), and V_GSoff (current 0). The 'I=...@Vg=...' format is a compromise to have voltage and current in one text line.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 19, 2023, 05:59:19 pm
2. I believe my T4 is at the latest version and it's calibrated. Got it from Kubi40's github repo a couple weeks ago. Is madires' the m-firmware you're referring to? Should I expect different results with that one?
It is likely that there will be other results, which is why I suggested that you try the madires m-firmware.

I'm looking for it. I need to recompile it to flip the display vertically, if you remember. But madire's repo is very different from kubi48's one. Is this it, please?
https://github.com/madires/Transistortester-Warehouse

Also, what about my friend's TC1? Will he get Idss and Vgsoff readings if he updates the firmware, or is that a limitation of that particular device?
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 19, 2023, 06:04:03 pm
The TC1 shows just V_GS (and the corresponding current) with the JFET's gate pulled down via the 470k test resistor. Yes, the 680 Ohms resistor is used as current shunt. Can't say much more about the TC1's firmware as it is a modified k-firmware (fancy UI, less features, no source available). Your T4 shows I_DSS, V_GS with gate pulled down via 470k (plus current), and V_GSoff (current 0). The 'I=...@Vg=...' format is a compromise to have voltage and current in one text line.

Oh, thanks for the info, that explains a lot. So no firmware upgrades for the TC1 then.
One thing I don't understand is, with a 470K source resistor, wouldn't that set the drain current very close to zero, hence measuring Vgsoff?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 19, 2023, 06:12:17 pm
Actually, I have two questions. I also have a few MMBFJ201 and MMBF5457, and they are both detected as BJT's by my T4, while his TC1 does spit out a reading, what's the deal there, please?
Some JFET-MOSFETs are not detected correctly by k-firmware, but are successfully detected by m-firmware.
I have experienced this effect many times. I also assume that Chinese firmware contains modified code not only for k-firmware but also partly for m-firmware. But I could be wrong about this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 19, 2023, 06:14:41 pm
Actually, I have two questions. I also have a few MMBFJ201 and MMBF5457, and they are both detected as BJT's by my T4, while his TC1 does spit out a reading, what's the deal there, please?
Some JFET-MOSFETs are not detected correctly by k-firmware, but are successfully detected by m-firmware.
I have experienced this effect many times. I also assume that Chinese firmware contains modified code not only for k-firmware but also partly for m-firmware. But I could be wrong about this.

Great, I'll try that.. I need to figure out how to flash madire's firmware with the display flipped vertically though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 19, 2023, 06:20:23 pm
Oh, thanks for the info, that explains a lot. So no firmware upgrades for the TC1 then.
One thing I don't understand is, with a 470K source resistor, wouldn't that set the drain current very close to zero, hence measuring Vgsoff?

No, the TC1 can be updated, but needs a mod for the additional control MCU (either a different firmware or a two-transistor-circuit). And yes, kind of.

Edit: ... as long as it comes with a genuine ATmega.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 19, 2023, 06:23:59 pm
So this is what I understand the meter should be doing, based on what's in the manual.
It initially measures Vgs an Id with a 680 ohm source resistor like this

(https://i.imgur.com/FQsSgtg.png)

These values represent an operating point somewhere in the middle of Vgsoff / Idss, and my guess is that's the info the TC1 is displaying, correct?

Then it adds a 470K source resistor to measure Vgsoff:

(https://i.imgur.com/U3fchEt.png)

Finally removes the source resistor to calculate Idss:

(https://i.imgur.com/CIet4Yd.png)

Not even close, probably, just trying to get a better picture of what's going on and what values each meter is displaying
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 19, 2023, 06:25:15 pm
No, the TC1 can be updated, but needs a mod for the additional control MCU (either a different firmware or a two-transistor-circuit).
Madires,as you know, now it is impossible to say with 100% certainty that the clones of the LCR-TC series can be upgraded, as there may be "surprises" from Chinese friends inside the package. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 19, 2023, 06:32:54 pm
So this is what I understand the meter should be doing, based on what's in the manual.
It initially measures Vgs an Id with a 680 ohm source resistor like this

All three circuits miss the 470k gate resistor. And in circuit #3 there's also a 680 Ohms source resistor. See CheckPins() in CheckPins.c for the details.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 19, 2023, 06:38:12 pm
OK, thanks again, guys, really appreciate you help. So the TC1 is showing something "close" to Vgsoff and the small drain-source current the fet is drawing in that condition, but doesn't measure Idss at all. Hope I got it right now.

I'll see if I can upgrade my T4 with madires' firmware and that allows me to measure my fets. Is the procedure the same as with kubi48's firmware? Where is madires repo?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 19, 2023, 06:51:07 pm
Nope, TC1 doesn't show V_GSoff or anything close. For the m-firmware please see https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 19, 2023, 06:57:53 pm
Some JFET-MOSFETs are not detected correctly by k-firmware, but are successfully detected by m-firmware.
Here is an example of how JFET-N J201 detection differs on k-firmware and m-firmware  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 19, 2023, 07:04:22 pm
I have madires' code compiled already with the added flag to flip the display, going to flash it now. Thanks, guys!
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 19, 2023, 07:26:30 pm
I have an issue with the display contrast, it's too high. I went to the menu and it was set to 22, but I don't know how to lower it, just kept increasing hoping it would cycle back to zero and up again, but it didn't. Also tried adding the CFLAGS += -DVOLUME_VALUE=10 flag to the makefile, but it seems to ignore it completely. Sorry to be such a pest, but can you guys please give me some pointers to fix this?

Using this: avrdude -p m328p -P usb -c usbasp -U flash:w:ComponentTester.hex -U eeprom:w:ComponentTester.eep
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 19, 2023, 07:35:31 pm
From the README:
Quote
You can adjust the contrast for some graphic LCD modules. A short key press
increases the value and and a long key press decreases it. Two short key
presses will exit the tool. With a rotary encoder installed the value
can also be adjusted by turning the encoder.

To change the default value check out LCD_CONTRAST in config_328.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 19, 2023, 07:58:47 pm
Got it working! It's now measuring my mmbfj201's, and the values for Idss and Vgsoff are almost identical to the ones I measured manually yesterday. Great stuff guys, vielen danke!
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 20, 2023, 12:54:06 pm
I'm still having a couple minor issues. The text in the display is shifted a little bit (see picture attached). I checked the flags in the documentation but couldn't find an obvious one to try, any ideas, please?

The second issue is, I added the POWER_OFF flag to the Makefile, but the tester keeps probing on a loop. Here's what I got in WinAVR, I added the last two compiler flags, and it compiles without error, not sure what I'm doing wrong.

Code: [Select]
# compiler flags
CC = avr-gcc
CPP = avr-g++
CFLAGS = -mmcu=${MCU} -Wall -I. -Ibitmaps
CFLAGS += -DF_CPU=${FREQ}000000UL
CFLAGS += -DOSC_STARTUP=${OSC_STARTUP}
CFLAGS += -gdwarf-2 -std=gnu99 -Os -mcall-prologues
CFLAGS += -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
#CFLAGS += -flto
CFLAGS += -MD -MP -MT $(*F).o -MF dep/$(@F).d
CFLAGS += -DLCD_ST7565_V_FLIP=1
CFLAGS += -DPOWER_OFF

EDIT: Wait a minute, I commented out both those flags I added, compiled, flashed... and it made no difference. Looks like it's ignoring them completely.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 20, 2023, 01:11:25 pm
For the m-firmware edit config.h and config_328.h, as explained in the README. And don't add random flags to the Makefile! The shift of the display is caused by LCD_OFFSET_X (config_328.h). Simply comment it out. For probing cycles see CYCLE_DELAY, CYCLE_MAX and POWER_OFF_TIMEOUT (config.h).
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 20, 2023, 01:26:23 pm
For the m-firmware edit config.h and config_328.h, as explained in the README. And don't add random flags to the Makefile! The shift of the display is caused by LCD_OFFSET_X (config_328.h). Simply comment it out. For probing cycles see CYCLE_DELAY, CYCLE_MAX and POWER_OFF_TIMEOUT (config.h).

Oh, by README I thought you meant the pdf documentation. Sorry about that, got it now.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 20, 2023, 01:44:26 pm
This is an important difference for compiling k-firmware and m-firmware I think will be very useful for many people to know:
In the k-firmware all the basic settings before compiling are made by editing the file "Makefile". In the m-firmware the global settings are concentrated in 3 files: "Makefile", "config.h" and "config_<mcu>.h
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 20, 2023, 02:24:56 pm
All is good now, thanks guys.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 20, 2023, 03:33:44 pm
The RTFM hint is really nice! I think I should add it as a default option, mabye UI_RTFM? ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 20, 2023, 03:57:10 pm
The RTFM hint is really nice! I think I should add it as a default option, mabye UI_RTFM? ;D
I also suggest that the RTFM be placed on the start page as well as in the "DATA" section ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: RoGeorge on January 20, 2023, 04:22:52 pm
Maybe make that an option, not the default.

Such a warning will become annoying from day one.  Will also defeat the whole idea of this instrument.  This instrument stands out exactly because it needs zero training.  Connect something and whatever you throw at it, the instrument does the rest.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dazz on January 20, 2023, 04:29:25 pm
I vote for slapping the entire README in a "welcome" screen and force the user to scroll down the whole thing before getting a reading.  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 20, 2023, 04:35:50 pm
Maybe make that an option, not the default.
Don't take my post above too seriously. Pay attention to the emoticons. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 22, 2023, 12:41:54 am
elecdonia,I think you may back edit your post regarding ATmega324 and its support in k-firmware. ;)
I am very eager to get LCR-TC2 containing either ATmega324 or ATmega644. So far I received one unit with LGT8F328P and another with APT32F172K8T6. So a week ago I ordered a third unit described by vendor as LCR-TC2.
Great news: I received the LCR-TC2 today. It contains ATmega324. I don’t have photos to post yet, but I did confirm the PC board looks exactly like the PC board in this post:
     https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4639780/#msg4639780 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4639780/#msg4639780)

My plan is to replace the ATmega324 with ATmega644. However I think I will try out the -k and -m firmware for ATmega324 first, before upgrading the MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vever001 on January 22, 2023, 07:16:52 pm
Hi everyone,

I have a TC-1 model. Everytime I want to use my tester the battery is flat  :horse:
I'll probably make the recommended TC-1 mod from https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/TC1-Mod.kicad.tgz (https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/TC1-Mod.kicad.tgz) to prevent the battery getting drained.
But I would also like to change the tiny litium cell in it for 1 or 2 standard 18650 cells.
I will also probably design and 3D print a suitable case for it.

Now I see the lithium cell has a BMS.
If I go with a single 18650, can I reuse the existing BMS?
Can I safely wire two 18650 cells in parallel each having their own BMS?
If so what kind of BMS should I choose?
Do I really have to use BMSes in the first place or is it just for safety?

Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 22, 2023, 07:55:01 pm
Hi everyone, I have a TC-1 model. Everytime I want to use my tester the battery is flat  :horse:
There may be something in the hardware which stays on all the time even when display is off.

Please measure the current flow from the battery to the PC board for both the operating state (display on) and the sleep state (after display turns off) and post the results.

Also please post photos of the PC board.
Several different manufacturers are now producing LCR-TCx units. So far I have identified 3 totally different circuit designs:
   1) LCR-TC1 with APT32F172K8T6 MCU, 32-pin TQFP square package. This is same size package as ATmega328. But totally different pinout.
   2) LCR-TC1 with LGT8F328P MCU. Also 32-pin TQFP. Pinout is different than ATmega328, also different than APT32F172K8T6.
   3) LCR-TC2 with ATmega324 MCU, 44-pin TQFP package. I think older LCR-TC1 units (2021 and before) also contained ATmega324 MCU.

So far all of my LCR-TC1 (or -TC2) units hold a battery charge for several weeks or more. I will endeavor to measure their battery currents and post the results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vever001 on January 22, 2023, 09:13:57 pm
Wasn't the issue already identified by those who created the TC1-mod? Which is supposed to fix this exact issue I believe.
Right now I'm running the alternative firmware for the U4 chip https://github.com/atar-axis/tc1-u4

I have the version with ATmega324PA, so circuit design n°3 that you described.
I'll measure the current draw when I have some time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: RoGeorge on January 22, 2023, 09:28:21 pm
Everytime I want to use my tester the battery is flat

Mine (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4643827/#msg4643827) has the same 9V alkaline battery since 2015.  The instrument is used rather rare, but the battery was connected all this time.  Battery is less than half now.  There is no mechanical switch.  The instrument goes to standby by itself, at a few seconds after each measurement. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: masterdums on January 22, 2023, 09:33:15 pm
Hello. Can you share the project in Proteus?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on January 23, 2023, 12:18:02 am
Hi everyone, I have a TC-1 model. Everytime I want to use my tester the battery is flat  :horse:
There may be something in the hardware which stays on all the time even when display is off.
If we're talking about an unmodified old version of the TC-1, that's a known issue. If you dig into the messages of june 2018 of this thread, you will find recommendations for replacing the U3 (or U4) that draws some idle current (with the screen off), replace it with a new power management circuit, and flash the m-firmware (don't forget to set the fuses too).

Or if you have one of the new non-Atmega versions, maybe you need to check the battery itself (and the new shipped batteries are tiny).

I think older LCR-TC1 units (2021 and before) also contained ATmega324 MCU.
Also the old versions of the T7. For more details, you can consult the Table of Clones.

Title: Re: $20 LCR ESR Transistor checker project
Post by: vever001 on January 23, 2023, 07:04:09 pm
Indeed, this was my understanding.
I plan to replace U4 with the TC-1 mod but I would also like to use 18650 batteries since the current battery is tiny.

My main questions was about the BMS and possibly wiring 2 18650 in parallel.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 23, 2023, 07:54:59 pm
My main questions was about the BMS and possibly wiring 2 18650 in parallel.
Why attach an 18650 and a BMS module if you can use a 2600mAh battery and forget about the power supply problem? ;)
This battery fits perfectly in the TC-1 case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: py-bb on January 24, 2023, 01:45:11 pm
So I had one of these (a T7) but it just broke and now thinks everything's a zener diode. Any idea where one can get a "good" one - I love the feature set and speed - it was a great tool but yeah I'm annoyed now. Would appreciate any advice.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on January 24, 2023, 03:01:27 pm
If the one you have has a protection IC, try removing it. Else, it looks you will have to find a replacement unit. The "good ones" are "old stock", so try thinking where to find that for your country.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 25, 2023, 05:10:16 pm
So I had one of these (a T7) but it just broke and now thinks everything's a zener diode. Any idea where one can get a "good" one - I love the feature set and speed - it was a great tool but yeah I'm annoyed now. Would appreciate any advice.
Try this: Connect DC voltmeter to “A” and “K” zener test ports. Minus to “A,” plus to “K.” Then press LCR-T7 “START” button and observe voltmeter. It should read >25V. If <24V then there is a fault in the DC-DC converter circuit which steps up from the battery voltage to the expected 25-30V zener test voltage.

I believe the software checks this “A” to “K” voltage first. If >25V then it concludes “no zener is connected” and moves on to performing the standard transistor tester tests at ports 1,2,3. But if open-circuit voltage from “A” to “K” is <24V then it stays in zener test mode and won’t do anything else.

Also please test several zener diodes, for example 5V, 12V, 15V zeners. Are the results within +/- 1V of the zener’s rated voltage? Also while testing a zener diode: Does the zener get hot after few seconds? (It shouldn’t). If zener gets hot there is definitely a fault in the zener test hardware circuit.

I have three different LCR-x transistor testers with totally different internal circuit designs. Starting in 2022 some Chinese manufacturers substituted <$1 USD MCU chips for the traditional Atmel ATmega328, -324, or -644 MCU ( >$5 USD each and rising ). One of my LCR units with non-Atmel MCU developed the “zener gets hot” fault but otherwise still works OK otherwise.

My units have the following open-circuit voltages from K to A:
LCR-TC2 with  Atmel ATmega324 MCU:   25.4V
LCR-TC1         APT32F172K8T6 MCU:      30.2V
LCR-TC2         LGT8F328P MCU:             25.2V

Note: The Chinese manufacturers interchangeably label their models as LCR-T7, LCR-TC1, or LCR-TC2.The only way to identify “what is inside the plastic box” is from a photo of the PC board. However the vendors don’t provide photos of the PC boards. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: py-bb on January 25, 2023, 08:06:05 pm
So I had one of these (a T7) but it just broke and now thinks everything's a zener diode. Any idea where one can get a "good" one - I love the feature set and speed - it was a great tool but yeah I'm annoyed now. Would appreciate any advice.
Try this: Connect DC voltmeter to “A” and “K” zener test ports. Minus to “A,” plus to “K.” Then press LCR-T7 “START” button and observe voltmeter. It should read >25V. If <24V then there is a fault in the DC-DC converter circuit which steps up from the battery voltage to the expected 25-30V zener test voltage.

I believe the software checks this “A” to “K” voltage first. If >25V then it concludes “no zener is connected” and moves on to performing the standard transistor tester tests at ports 1,2,3. But if open-circuit voltage from “A” to “K” is <24V then it stays in zener test mode and won’t do anything else.

Also please test several zener diodes, for example 5V, 12V, 15V zeners. Are the results within +/- 1V of the zener’s rated voltage? Also while testing a zener diode: Does the zener get hot after few seconds? (It shouldn’t). If zener gets hot there is definitely a fault in the zener test hardware circuit.

I have three different LCR-x transistor testers with totally different internal circuit designs. Starting in 2022 some Chinese manufacturers substituted <$1 USD MCU chips for the traditional Atmel ATmega328, -324, or -644 MCU ( >$5 USD each and rising ). One of my LCR units with non-Atmel MCU developed the “zener gets hot” fault but otherwise still works OK otherwise.

My units have the following open-circuit voltages from K to A:
LCR-TC2 with  Atmel ATmega324 MCU:   25.4V
LCR-TC1         APT32F172K8T6 MCU:      30.2V
LCR-TC2         LGT8F328P MCU:             25.2V

Note: The Chinese manufacturers interchangeably label their models as LCR-T7, LCR-TC1, or LCR-TC2.The only way to identify “what is inside the plastic box” is from a photo of the PC board. However the vendors don’t provide photos of the PC boards.

While I appreciate the thought a diode sort of burned itself in two and it's next to some very unhealthy looking components, I accidentally scraped the diode off trying to clean it up a bit and see what it was and yeah it's bad...

No idea why this happened either, I've been treating it right!
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 25, 2023, 08:38:59 pm
While I appreciate the thought a diode sort of burned itself in two and it's next to some very unhealthy looking components, I accidentally scraped the diode off trying to clean it up a bit and see what it was and yeah it's bad...

No idea why this happened either, I've been treating it right!
I bet you have the same (very poorly designed) LCR-Txx model that I received a couple of months ago. Does the area where the PC board has bad (cooked) components look like the attached photo? And is the toasted diode labeled D2?
Title: Re: $20 LCR ESR Transistor checker project
Post by: GraemeG on January 25, 2023, 10:51:31 pm
I have just received a "TC1" of this latest design elecdonia. Within a couple of days it failed while testing a few zeners and schottky diodes on the K-A terminals. After the failure it would always show a 4.1V zener across the K-A terminals and when I opened the box it was obvious that D2 was burned.

I was able to find a replacement SMD diode for D2 and it was soon working again but I noticed whenever I tested a zener diode both the zener and D2 would get very hot. Apparently there is nothing to limit the current through D2 and the tested device other than the ability of the DC-DC converter circuit to supply current!

I found a solution on another site (that I now can't find) that suggested cutting the track between C14 and the K terminal and inserting a 4K7 resistor. This limits the current to about 6-7mA even into a short circuit on K-A. This seems to work perfectly! Originally I tried a 10K resistor but the voltage drop was a bit too much and the tester identified it as a zener of about 27V. With the 4K7 resistor the open circuit K-A voltage is 29.7V and this is high enough that the detector assumes no zener is connected.

With an oscilloscope I also noticed that the test voltage was not very well filtered with about 1V peak-peak of 1kHz ripple. I added a 1uF 50V low ESR electrolytic from the K terminal to ground and this dramatically reduced the ripple but to be honest I'm not sure it changed the test results very much. I have tested several zeners now and there is no sign of over heating. The test results seem to be low by perhaps 0.3-0.6V but it's a bit difficult to be sure as there is some variation in diodes and the voltage does depend a little on the test current. In any case it is near enough to give a good/bad indication and if I open the box again some time I might tweak the voltage divider to give a slightly better result.

The bottom line is that every tester of this latest design is almost certain to fail when testing zeners, particularly low voltage zeners and or diodes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 26, 2023, 07:14:10 am
I have just received a "TC1" of this latest design elecdonia. Within a couple of days it failed while testing a few zeners and schottky diodes on the K-A terminals. After the failure it would always show a 4.1V zener across the K-A terminals and when I opened the box it was obvious that D2 was burned.
This failure will occur sooner or later to every LCR-TXx unit having this PC board design where the 30V power source rail connects directly to the test socket K terminal.  This manufacturer really “went their own way” with both hardware and software. Unlike the original OSHW Transistor Tester zener test circuit, which has a “step-up switching voltage regulator” IC generating a steady 30V rail followed by a 10K series resistor, this manufacturer substituted a “step-up constant-current LED driver” IC. Their main mistake is they failed to place a proper series resistor >2K2 ohms between the 30V rail and pin K.
Quote
I was able to find a replacement SMD diode for D2 and it was soon working again but I noticed whenever I tested a zener diode both the zener and D2 would get very hot. Apparently there is nothing to limit the current through D2 and the tested device other than the ability of the DC-DC converter circuit to supply current!
Here’s what happened: When a zener or a diode (forward-biased) is connected between K-A while the tester is in a powered up state, this damages the current sensing input pin of the step-up IC (U7 on PC board). Actually any electronic component with low resistance <1K ohms or a capacitor with low ESR could cause this failure. This pin on the step-up IC (U7) has a maximum input voltage of 4V. This IC pin is connected to the A terminal of the test socket. Worst case is placing a direct short between K and A while the LCR tester is powered up with the LCD screen turned on. There is a filter capacitor (C14) on the 30V rail (K on test socket). C14 carries a 30V charge. Making a short circuit from K-A dumps all the energy stored inside C14 straight into the current sensing pin of the step-up IC. Although the duration may be brief, 30V is a lot more than 4V. In many cases only the current sensing portion of U7 gets destroyed. The rest of U7 continues to operate, generating 30V without any current limiting. This allows the peak current up to 500mA  through K-A. This is why a zener under test can get extremely hot almost instantaneously.
Quote
I found a solution on another site (that I now can't find) that suggested cutting the track between C14 and the K terminal and inserting a 4K7 resistor.
I used a 2K2 series resistor in my unit. If the series resistance is larger the tester may report that a zener is being tested while the K-A pins are open-circuit. A value of 2K2 is sufficient to protect U7 from damage.

To conclude, the fix is:
1) Cut the PC board foil leading to pin K and then connect 2K2 resistor from junction of D2 and C14 to pin K,
2) Replace U7
3) Replace D2 if faulty or burned
4) Check that open circuit voltage from K to A is approximately 30V
5) Place a 1K resistor across K-A and confirm that tester identifies this as a 5 to 7V zener.
Title: Re: $20 LCR ESR Transistor checker project
Post by: GraemeG on January 26, 2023, 09:17:26 am
this manufacturer substituted a “step-up constant-current LED driver” IC.

Thanks for this, I had not checked out the DC-DC converter circuit and did not realise the design change they had made. It is likely that the current sensing input is damaged on my device but it is still generating about 31.5V on C14 so with a new D2 and the extra resistor before the K terminal I still have a working circuit  :)

A 1K resistor between K and A reads as a 5.2V zener but this is with the 4K7 resistor that I used instead of the 2K2 you recommend. If I have it open again some time I might change the resistor as I am not sure how close I am to the threshold where the code decides a zener is connected to the K-A terminals. The built in battery is currently 3.87V and the zener circuit with 4K7 resistor is producing 29.7V on open circuit K-A terminals but this may drop as the battery discharges. Time will tell!
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on January 30, 2023, 02:07:14 pm
Just bought a tester marked Multi-function Tester - TC1 from ebay.
It is never able to test any component but it does boot up ok and the display is ok.

It doesn't recognise any components in the 1,2,3 sockets, it just displays "unknown or damaged part" after
pressing the start button.

I have tried a lot of other simple components and I get the same result.
If I put a diode in the (K, A) part of the socket it does recognise it as a zener, so it seems to be stuck in zener mode.

It has a blue PCB with no transformer, uploaded a photo. On the clones table it looks like a TC1(2), but can't find
a schematic anywhere. cant see any damage on the pcb.

I just got the tester for resistors, capacitors and transistors and I don't need the zener function which seems
to be problematic in any case.

Anyone know how to completely remove and disable the zener testing function?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 30, 2023, 03:15:54 pm
If your TC1 doesn't detect any component connected the standard test pins then it's obviously broken. Have you notified the seller and asked for a replacement? In case of a genuine ATmega you can try an OSHW firmware and run the selft-test to check the test pins. The OSHW firmware can also be customized, e.g. disabling the Zener check.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on January 30, 2023, 03:19:10 pm
I think its time to put out a strong warning
about fake transistor testers.
The good times are definitely over. :scared:
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 30, 2023, 03:21:45 pm
In case of a genuine ATmega you can try an OSHW firmware and run the selft-test to check the test pins.
Madires, this is not a genuine ATmega.This clone variant is built on LGT8F328.I also advise the clone owner to contact the seller with a complaint about a faulty device.In addition, I see a lot of traces of flux on the board, which can negatively affect the quality of work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on January 30, 2023, 04:36:06 pm
Thanks for the info. I have already got a refund from the seller and they let me keep the fake box, so I will play with it later. ;)
I have ordered a DIY kit tester instead so hopefully I will have more luck with this.  :P
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 31, 2023, 04:09:09 am
Just bought a tester marked Multi-function Tester - TC1 from ebay. It is never able to test any component but it does boot up ok and the display is ok. It doesn't recognise any components in the 1,2,3 sockets, it just displays "unknown or damaged part" after pressing the start button.
Have you performed the “self-adjustment” procedure?
Do this by shorting test socket pins 1, 2, 3. The metallic strip of 3 crimp pins supplied with these LCR-Txx units can be used for this. Take care to place it so that it shorts pins labeled 1-2-3. Then press the button. It should display “self test.” After 10-30 seconds it should display “isolate probes.” Now pull out the short circuit and it should eventually display “test complete.”
Quote
If I put a diode in the (K, A) part of the socket it does recognise it as a zener, so it seems to be stuck in zener mode.
If your tester displays “unknown or damaged part” then it isn’t stuck in zener test mode.
Quote
It has a blue PCB with no transformer, uploaded a photo.
The unit in your photo is likely to be a clone using the LGT8F328P MCU.

Unfortunately the software is proprietary and cannot be upgraded. Eventually the open-source Transistor Tester software might get ported to the LGT8F328P MCU, but I’m not expecting this anytime soon. Note: The LGT8F328P claims to be an improved version of the Atmel ATmega328P. However it isn’t fully compatible at either the hardware (different pinout) or software level. This MCU is made by a Chinese semiconductor company named “LogicGreen.”

I have a similar unit with LGT8F328P MCU. It functions but has issues (inaccurate for some types of transistors). It does measure resistors, capacitors, and inductors reasonably well.

I discovered a way to identify units with LGT8F328P MCU: Press and hold down the button for 30 or more seconds. The display language should switch from English to Chinese. Wait till tester times out and powers off, then press and hold the button for another 30+ seconds to switch back to English.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on January 31, 2023, 10:11:35 am
Yes I tried the self test and just got the “unknown or damaged part” message. After pressing Start testing across the 1,2,3 pins gives 0 volts. testing across K,A gives 25.4v. Do you know what voltage I should get across the 1,2,3 pins after pressing the start button?

Thinking that there could be a bad connection to the test pins somewhere, might try working my way back re-soldering the joints. other than this thinking the 6 pin V05 (D2) might need swapping.

Yes, if I press the Start button for around 30 seconds the language does change to Chinese.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on January 31, 2023, 01:23:49 pm
If you have an oscilloscope at hand, you could try to see whether there are pulses on the 123 positions when you press the test button.
With a DMM you could double check the continuity of the traces.
If the MCU is damaged, there's nothing more to do.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on January 31, 2023, 04:11:47 pm
Yes I tried the self test and just got the “unknown or damaged part” message. After pressing Start testing across the 1,2,3 pins gives 0 volts. testing across K,A gives 25.4v. Do you know what voltage I should get across the 1,2,3 pins after pressing the start button?
OK, I will post the voltages from my LCR-TC1 which contains the LGT8F328P MCU. Its PC board is similar to yours.
Quote
Thinking that there could be a bad connection to the test pins somewhere, might try working my way back re-soldering the joints.
My experience is that shorts from solder bridges occur more often than open circuits from dry joints. I recommend a close visual inspection with a strong magnifier, microscope, or close-up photos taken by smartphone.
Quote
…other than this thinking the 6 pin V05 (D2) might need swapping.
When V05 failed in another of my Transistor Testers (different model) the display was “CELL” for one of the pins. I don’t recall which pin or the exact voltage reported by the “CELL” display message. FYI, “CELL” normally gets displayed when the tester software detects that a battery has been connected to the test pins. In my case V05 failed when I accidentally connected a charged capacitor. Replacing V05 fixed my tester.
Quote
Yes, if I press the Start button for around 30 seconds the language does change to Chinese.
This confirms you have the version with LogicGreen LGT8F328P MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on February 01, 2023, 10:41:45 am
Put the scope on the 1,2,3 pins, after pressing start I get a short series of pulses at 5 volts, except between pins 2 and 3 where I get 0 volts.

With the battery disconnected did a continuity test between 2 and 3 and have a short in both directions, can't see any obvious short, so I'll
need to trace the tracks and maybe try to draw a schematic, need to get a pinout for the MCU. At least PCB seems to have a 10k series resistor for
the K pin.

The short could be under the ZIF or the 6 pinV05, or a damaged MCU, at least the infra red remote test works ok.  lol.
Title: Re: $20 LCR ESR Transistor checker project
Post by: zzika on February 01, 2023, 09:33:51 pm
To conclude, the fix is:
1) Cut the PC board foil leading to pin K and then connect 2K2 resistor from junction of D2 and C14 to pin K,
2) Replace U7
...


Could you please tell me which step-up IC (U7) it is?

The marking on the my chip is  HYEQG.

Where can I buy those step-up IC?


Title: Re: $20 LCR ESR Transistor checker project
Post by: GraemeG on February 01, 2023, 09:57:49 pm
I don't know what chip U7 is but looking at your board D2 shows no sign of burning or heat. If you still measure 28-32V on the K-A pins with no component connected then U7 is still working and all you need to do is to cut the track between C14 and the K terminal and insert a 2K2 resistor. Once this change has been made this version of the tester seems to work well.
Title: Re: $20 LCR ESR Transistor checker project
Post by: zzika on February 01, 2023, 10:06:01 pm
I don't know what chip U7 is but looking at your board D2 shows no sign of burning or heat. If you still measure 28-32V on the K-A pins with no component connected then U7 is still working and all you need to do is to cut the track between C14 and the K terminal and insert a 2K2 resistor. Once this change has been made this version of the tester seems to work well.


The voltage on the K-A pins is 4V - the voltage of the Ni-Mh battery.

I need to replace U7 but I can't find which circuit it is.




Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 02, 2023, 05:23:14 am
zzika, it is advisable for you to read this topic carefully or use the search system for the necessary information on the forum. Information about the U7 chip has already been discussed in this topic:
U7 - this is SY7200A (marking HY6VE)
Title: Re: $20 LCR ESR Transistor checker project
Post by: zzika on February 02, 2023, 09:40:42 am
This topic has 328 pages. Before asking the question I tried reading the discussions to find an answer, but without success. The search system could not find a suitable post for me according to the parameters I had.

Thank you for your response. I already ordered the SY7200A so if anyone needs info I'll leave a message here if everything is working as it should.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 02, 2023, 10:02:50 am
Before asking the question I tried reading the discussions to find an answer, but without success. The search system could not find a suitable post for me according to the parameters I had.
In the screenshots below, I show you that the search engine on this forum is working fine. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: RoGeorge on February 02, 2023, 10:06:11 am
LOL, thanks, I didn't know that button either.  ;D
Was using Google with site:eevblog.com appended in the search terms.
Title: Re: $20 LCR ESR Transistor checker project
Post by: py-bb on February 02, 2023, 03:40:16 pm
While I appreciate the thought a diode sort of burned itself in two and it's next to some very unhealthy looking components, I accidentally scraped the diode off trying to clean it up a bit and see what it was and yeah it's bad...

No idea why this happened either, I've been treating it right!
I bet you have the same (very poorly designed) LCR-Txx model that I received a couple of months ago. Does the area where the PC board has bad (cooked) components look like the attached photo? And is the toasted diode labeled D2?

Sorry for late reply, you're exactly right it's that bit. My diode was far more visibly cooked though it'd basically popped in half.

Any recommendations on getting a long and happy life out of the replacements? I apologise you clearly know a lot about the model and I regret treating mine as screwed (I used it for heatgun practice)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on February 02, 2023, 10:05:24 pm
The short could be under the ZIF or the 6 pinV05, or a damaged MCU, at least the infra red remote test works ok.  lol.
Check very closely for solder bridges at all locations where the PC board foils for test socket terminals 2 and 3 connect to the MCU, to the V05 protection device, and to the group of 680R and 470K resistors. You will need a microscope or a strong magnifier. These pins 2 and 3 connect straight to 2 pins on the MCU which may be right next to each other. Even if you don’t find a visible solder bridge it is a good idea to reheat these IC pins after applying solder flux to them. The solder flux is the important part: Flux permits solder bridges to separate when the solder melts. If you find a big blob of solder anywhere then use desoldering wick to absorb the excess. I recently learned to add additional solder flux to the desoldering wick before using it. Even though the wick already contains flux, “everything works better with extra flux” when correcting solder bridges.

If there aren’t any solder bridges then I suggest removing the V05 protection IC as the next step. Although V05 is rated at 10A peak current it isn’t totally bulletproof. It is safe to operate the transistor tester with V05 removed as long as you are careful to discharge capacitors before testing them. If V05 is the culprit then get another one and replace it before using the tester heavily. I have a tester where V05 did fail. Everything worked again after removing the faulty V05. It sacrificed itself to save the MCU.

A short underneath or inside the ZIF test socket is unlikely but if nothing else clears the short between pins 2 and 3 then I recommend desoldering and removing the ZIF socket. There is a first time for every failure.

Here’s the most important thing: Your transistor tester has a direct short between ZIF pins 2 and 3. But this isn’t a short to ground or +5V is it(please confirm)? When an IC fails it will often have pins shorted to ground or VCC (+5V in this case). It isn’t likely for 2 pins of an IC to short to each other without also being shorted to ground or VCC.

Summary: If the only short in your unit is between pin 2 and pin 3 this means there are only a small number of causes for this fault.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on February 02, 2023, 10:19:13 pm
Any recommendations on getting a long and happy life out of the replacements? I apologise you clearly know a lot about the model and I regret treating mine as screwed (I used it for heatgun practice)
Replace diode D2 and step-up IC U7. Add a 2K2 series resistor between the junction of D2/C14 and the K pin of the ZIF socket. This requires cutting the PC board foil between these two points. Doing this will make the zener testing circuit unbreakable.

It’s a pity the manufacturer neglected to include the 2K2 series resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on February 02, 2023, 10:26:34 pm
Put the scope on the 1,2,3 pins, after pressing start I get a short series of pulses at 5 volts, except between pins 2 and 3 where I get 0 volts.
Are pins 2 and 3 both shorted to ground?
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on February 03, 2023, 09:32:02 am
Sorry yes, pins 2 and 3 are shorted to ground, so likely no short under the ZIF.

I guess that likely means V05 is bad?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 03, 2023, 01:58:35 pm
I guess that likely means V05 is bad?
Maybe. You can remove it and mesure again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on February 03, 2023, 03:35:23 pm
Sorry yes, pins 2 and 3 are shorted to ground, so likely no short under the ZIF. I guess that likely means V05 is bad?
It is very likely that V05 failed. Try removing it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on February 03, 2023, 10:23:28 pm
Removed V05, but the short still exists, it must be a defective MCU, reached the end of the road with this clone box.
Anyway I've got a AY-AT kit on the way with loads more options, so no loss  :P
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 04, 2023, 12:05:18 pm
A final test you can do: cut a trace and measure the ports directly.

And you can save the protection IC for future use.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on February 04, 2023, 04:03:04 pm
Removed V05, but the short still exists, it must be a defective MCU, reached the end of the road with this clone box. Anyway I've got a AY-AT kit on the way with loads more options, so no loss  :P
I recently bought an AY-AT kit. For years I’ve had a factory-built AY-AT. It has served me well. In fact it is getting a bit shabby from years of daily use.

Because these AY-AT kits are so cheap ($10-12 USD) I decided to get one. I’ve assembled my AY-AT kit and am beginning to test it.

In addition I fired up my MCU programming kit in order to try out different TransistorTester firmwares. My programming device is an Arduino UNO loaded with the standard “Arduino as ISP” sketch. I recently obtained a nifty programming shield for it which has a ZIF socket. Another cool item I just started using is the superb AVRDUDESS GUI front-end app for AVRDUDE. Wow! It makes programming chores much faster and easier!

At this time my two AY-AT units are still running their original Asian factory firmware. Both are a modified 1.12k. Each is slightly different. The older unit has fewer items in the user menu compared to my new AY-AT kit. Unfortunately the MCU flash is locked in my older unit so I won’t be able to directly compare flash contents. However the ATmega328P which came with my new AY-AT kit is unlocked. I’ve already grabbed the contents of its flash and EEPROM.

My next task is to get both of them to run the 1.13k firmware. I have a whole tube of brand-new ATmega328P. Both of my AY-AT units have a socket for the MCU, making it very easy to swap different firmwares.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on February 04, 2023, 10:38:33 pm
A final test you can do: cut a trace and measure the ports directly.
Yes I did cut the trace next to the MCU at pin 24, I can confirm 100% the short is at the MCU.

Is it worth swapping out the MCU for a real ATMega? probably not. would it work with this clone board?
then I would need to program the replacement with the open source firmware, I'll keep the box in case I try to give it a go.  :box:
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on February 04, 2023, 10:42:46 pm
Removed V05, but the short still exists, it must be a defective MCU, reached the end of the road with this clone box. Anyway I've got a AY-AT kit on the way with loads more options, so no loss  :P
I recently bought an AY-AT kit. For years I’ve had a factory-built AY-AT. It has served me well. In fact it is getting a bit shabby from years of daily use.

Because these AY-AT kits are so cheap ($10-12 USD) I decided to get one. I’ve assembled my AY-AT kit and am beginning to test it.

AY-AT kit looks like a good choice then. I noticed there are a few upgrades you can do like swapping out the crystal, and upgrading the voltage regulator.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 05, 2023, 12:06:27 am
Is it worth swapping out the MCU for a real ATMega? probably not. would it work with this clone board?
then I would need to program the replacement with the open source firmware, I'll keep the box in case I try to give it a go.  :box:
As elecdonia recently mentioned, there are at least 3 kinds of alternate MCUs for this series of ctester. If you modify the pinout for a valid ATmega, you could swap the damaged MCU, but you would also need to replace the power controller MCU with a circuit previously described in this thread, and program the new ATmega with the m-firmware. Would it worth it? For me, if the options were throw it away, or rescue it for few pounds, I would proceed and later rejoice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 05, 2023, 06:45:30 am
As elecdonia recently mentioned, there are at least 3 kinds of MCU for this series of ctester. If the pinout is valid for ATmega, you could swap the damaged MCU, but you would also need to replace the power controller MCU with a circuit previously described in this thread, and program the new ATmega with the m-firmware.
This is not the case, you are slightly mistaken here.I do not see any difficulties and obstacles in order to bring this clone back to life and normal operation. LGT8F328 is 99% similar to ATmega328 in terms of the location of contacts. Therefore, here is the procedure that should be done:
1. Remove the old controller from the board.
2.Before installing ATmega328, carefully compare those contacts that are designed for normal ATMEL operation and activate them.This applies to pins 3,6,18,21
3.Compile a new firmware for ATmega328.This is perhaps the most difficult point for beginners, but also realizable. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 05, 2023, 07:08:13 am
Madires,as you know, now it is impossible to say with 100% certainty that the clones of the LCR-TC series can be upgraded, as there may be "surprises" from Chinese friends inside the package. :D
Here is 1 more version of the LCR-T4 "surprise" from Chinese friends on LGT8F328. However, it can also easily be redesigned to work with genuine ATMEL. It remains only to purchase a few spare ATmega328 from the same Chinese friends! :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 05, 2023, 12:54:55 pm
2.Before installing ATmega328, carefully compare those contacts that are designed for normal ATMEL operation and activate them.This applies to contacts 3,18,21
indman, thanks for bringing this to my attention, but I think you forgot the pin 6.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 05, 2023, 01:10:09 pm
but I think you forgot the pin 6.
Yes, thanks you for noticing.I have apdate my post above.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: cincin on February 07, 2023, 01:07:39 am
I read a half-dozen pages back but couldn't find a clear answer: Where can one reliably purchase one of the better one of these nowadays?

From what I read back in this thread, the good ones are not sold anymore, or are hard to find old-stock, and there's a million lesser clones being sold as the good ones everywhere. Is that correct?

So there are no known reliable sources for decent ones? I'm probably not looking to tinker with it much (may not need to be flashable if it's already useful), just to use it for part ID and tester.

Cheers!
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on February 07, 2023, 04:25:30 pm
I read a half-dozen pages back but couldn't find a clear answer: Where can one reliably purchase one of the better one of these nowadays?
I recently purchased this LCR-TC2 unit:
     https://www.ebay.com/itm/LCR-TC2-Transistor-Tester-Diode-Triode-Capacitance-Meter-V2-3E-with-Tester-Cable/295395097022/ (https://www.ebay.com/itm/LCR-TC2-Transistor-Tester-Diode-Triode-Capacitance-Meter-V2-3E-with-Tester-Cable/295395097022/)

After inspecting it internally and using it for several weeks I confirmed it contains the desirable ATmega324P MCU. Its performance and accuracy are very good. The zener test feature works properly without overheating the zener diode being tested. The internal rechargeable lithium cell provides plenty of hours of use. In fact I haven’t needed to charge it yet.

Notes:
1) This unit has a dark blue front panel with manufacturer’s logo at top left (2 Chinese characters).
2) Model number is “LCR-TC2”
3) Version is “V2.3E”
4) The ebay listing contains a color image of a detailed user manual provided by the manufacturer. My unit arrived with a printed user manual identical to what was shown in the ebay listing.

I should mention that several months ago I acquired two other LCR- units which contained alternative (non-Atmel) MCU. Both had issues and faults. In my opinion they were barely functional. Those units had light gray front panels without any manufacturer’s logo. The ebay descriptions did not show the color image of the manufacturer’s user guide.

Conclusion: I do not recommend purchasing any LCR- unit other than this LCR-TC2 V2.3E unit with the dark blue front panel which carries the manufacturer’s Chinese logo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: cincin on February 07, 2023, 07:29:20 pm
Thanks! Unfortunately, that seller doesn't ship to Canada. But I will try to find that specific unit somewhere else. If anyone has a reputable lead that ships to Canada, please do tell.
Cheers!
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on February 07, 2023, 09:43:38 pm
Thanks! Unfortunately, that seller doesn't ship to Canada. But I will try to find that specific unit somewhere else. If anyone has a reputable lead that ships to Canada, please do tell.Cheers!
The ebay vendor I ordered my LCR-TC2 V2.3 unit from ships to USA locations from a warehouse inside the USA. That might be why they don't ship to Canada.

I know of several other Chinese ebay vendors who offer the exact same LCR-TC2 V2.3E unit. I've ordered from ebay vendors listed below. They have nearly always shipped what I expected. If there was any issue they immediately issued refunds.

     alice1101983 (557,445) 99.7%
     worldchips (181,380) 99.6%
     modulefans (109,038) 99.4%
     diybox (73,854) 99.4%

Another thing I noticed is most ebay listings for this version of the Transistor Tester include all of the following words in the listing title:

           high precision LCR-TC2 V2.3E

Therefore I recommend using the above words for searching on ebay
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrSqueaky on February 08, 2023, 09:02:44 am
I read a half-dozen pages back but couldn't find a clear answer: Where can one reliably purchase one of the better one of these nowadays?

I bought an LCR-TC2 back in December from Aliexpress https://www.aliexpress.com/item/1005004717377243.html (https://www.aliexpress.com/item/1005004717377243.html).

It contained an ATmega324 and has worked well so far https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4635052/#msg4635052 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4635052/#msg4635052)

Title: Re: $20 LCR ESR Transistor checker project
Post by: ws786873 on February 08, 2023, 12:15:51 pm
I bought an AY-AT clone and bought the resistor and IC needed for the upgrade. But when I wanted to burn the M firmware, I found that I could not find the pre-compiled firmware that could be burned in the Windows system... It seems that it needs to be compiled and burned on the Linux system... Can anyone provide the pre-compiled M firmware? I used 16MHZ crystal oscillator. ;D ;D ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: py-bb on February 09, 2023, 02:43:40 am
Any recommendations on getting a long and happy life out of the replacements? I apologise you clearly know a lot about the model and I regret treating mine as screwed (I used it for heatgun practice)
Replace diode D2 and step-up IC U7. Add a 2K2 series resistor between the junction of D2/C14 and the K pin of the ZIF socket. This requires cutting the PC board foil between these two points. Doing this will make the zener testing circuit unbreakable.

It’s a pity the manufacturer neglected to include the 2K2 series resistor.

Hi there, I've ordered 2 replacements as unfortunately being without this bit of tat sucks. Before I do the mods any recommendations? I have some diodes I need to test - should I be really careful in which way around they go?

I appreciate your advice on this as you clearly know a lot about these devices. Would you like to hear back if I do the mods?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: GraemeG on February 09, 2023, 02:58:53 am
Assuming you have that particular version of the tester, my advice is DO NOT test anything on the zener test pins (K - A) until you have made the mods. You might get away with it if it is a higher voltage zener and you are fast but there is a good chance you will burn D2 and possibly damage the DC-DC boost IC.

I didn't have any SMD resistors of the right value but it is not too difficult to use a normal through-hole resistor. Cut the track near to the K pin and carefully scrape the copper clean on the track leading to D2. With the resistor lying flat on the board near the end of the ZIF sock pins, solder one lead of the resistor to the K pin (easy) then carefully adjust the other lead to align with the cleaned track. It shouldn't be too difficult to solder the lead to the track if you have a reasonably fine soldering iron tip.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 09, 2023, 12:11:05 pm
I bought an AY-AT clone and bought the resistor and IC needed for the upgrade. But when I wanted to burn the M firmware, I found that I could not find the pre-compiled firmware that could be burned in the Windows system... It seems that it needs to be compiled and burned on the Linux system...
If you prefer the m-firmware, you won't find it pre-compiled online, as there are many features one person may want to enable and other person don't. It's not so difficult to compile it yourself, you may want to read the "Clones" file for instructions on what to modify for your particular unit.
Regarding your other question, it's not mandatory to use linux, there are Windows tools for the task, let's say AVRdudess and others. You will also need the cable for programing it, and the toolchains.
For more infiormation, you can search old posts of this thread.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on February 09, 2023, 04:03:32 pm
<offtopic>
...I have some diodes I need to test - should I be really careful in which way around they go?
What do you want to measure? Zener voltage? Forward voltage? There are simple ways to measure diodes (Google it). You don't need to risk your tester.
</offtopic>
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on February 09, 2023, 09:50:24 pm
Assuming you have that particular version of the tester, my advice is DO NOT test anything on the zener test pins (K - A) until you have made the mods. You might get away with it if it is a higher voltage zener and you are fast but there is a good chance you will burn D2 and possibly damage the DC-DC boost IC.
There is one item which can be safely tested across the zener test pins (K-A) on every version of the Transistor Tester, modified or not:

        This item is a 1k ohm resistor

No matter what condition the Transistor Tester is in, the absolute maximum current which will flow through this 1k ohm resistor will be safe. It will be no higher than 30mA.

In fact the “zener voltage” displayed by the Transistor Tester (for the 1k resistor) represents the mA flowing from K to A.

     This is just Ohms Law: The voltage drop across a 1k ohm resistor is exactly 1V per mA.

Transistor Testers with the original OSHW zener test circuit will display 2-3V for “zener voltage” with 1k resistor connected to K-A. The original OSHW zener test circuit is a 30V DC source feeding the “K” pin through an internal 10k ohm series resistor. The “A” pin is grounded. This internal 10k series resistor therefore limits the absolute maximum zener test current to 30V/10k = 3mA.

In contrast, unmodified (but working) LCR- units with APT32F172K8T6 MCU and the poorly designed U7 circuit will display 5-8V “zener voltage” with the 1k resistor connected to K-A. This is because DC-DC converter U7 actually does function as a constant current source (until it gets damaged).

An LCR-TC1 where the current-limiting portion of U7 has been damaged, but where the rest of the circuit still works, will apply about 30V across the 1k resistor. In this case the tester may display “unknown or faulty component”. However, a multimeter connected in parallel with the 1k resistor will read 25-30V.

Finally, if D2 and/or U7 failed catastrophically, then the tester may report a zener voltage of either 0V or 4V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on February 09, 2023, 10:08:01 pm
Hi there, I've ordered 2 replacements as unfortunately being without this bit of tat sucks. Before I do the mods any recommendations? I have some diodes I need to test - should I be really careful in which way around they go?
I have a Transistor Tester just like yours where the current limiting feature of U7 failed, but fortunately I avoided roasting D2. Therefore my unit is still generates 30V, but without any current limiting. I went ahead and installed the 2k2 series resistor between the junction of D2/C14 and the K test socket pin. This limits maximum short-circuit current to about 15mA.

IMHO putting in the 2k2 series resistor alone is good enough to prevent anything from smoking.

I continue to recommend replacing U7 too. The 2k2 series resistor protects U7. Even if a direct short is placed from K to A, the 2k2 series resistor keeps U7 safe and happy. After installing a new U7, testing with the 1k resistor should display a “zener voltage” of 5-6V. This indicates U7 is properly limiting the zener test current.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrSqueaky on February 11, 2023, 03:35:41 am
I've discovered a problem with the reference voltage on pin PA3 for my stock LCR-TC2. I was looking at the config.h file of the m-firmware and saw an option for defining the reference voltage so I decided to measure it on my tester but found it was only 45mV.

The TL431 works fine out of circuit so I cut the trace going to PA3 and now the reference voltage is 2.495V. So something is wrong with PA3 pin or it is not being configured properly by the firmware. The resistance between PA3 and ground is ~26 ohms when powered and open circuit when not powered. The voltage drop between 5V and PA3 is 5V so it must be being pulled low.

I'll try to compile and upload the m-firmware and see if the problem still persists.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 11, 2023, 01:29:46 pm
Have you enabled HW_DISCHARGE_RELAY by chance? That would ground the TP_REF pin (in your case PA3) between probing cycles.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrSqueaky on February 11, 2023, 03:28:15 pm
Have you enabled HW_DISCHARGE_RELAY by chance? That would ground the TP_REF pin (in your case PA3) between probing cycles.

The reference voltage problem was with the original Chinese firmware (3.1E). I compiled the 1.48m firmware and uploaded it. Now when I press the test button I get a white screen that turns off after 30s.

The LCD is a 14 pin Z180SN009 (same as TC1 I think). I used the display configuration for the TC1 (ST7735). According to my multimeter LCD_RES stays low the whole time which might explain the white screen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 11, 2023, 04:15:06 pm
The 'original Chinese' firmware is a modified k-firmware. And apparently they didn't disable the support for the discharging relay. When LCD_RES stays low then there could be something wrong with the configuration, e.g. same pin also used for some other function.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 11, 2023, 04:16:50 pm
I've discovered a problem with the reference voltage on pin PA3 for my stock LCR-TC2. I was looking at the config.h file of the m-firmware and saw an option for defining the reference voltage so I decided to measure it on my tester but found it was only 45mV.
This is not a problem, but a feature of the tester that you need to know and take into account. In this circuit, the PA3 pin of the MCU is periodically connected to ground (by software), so the reference voltage of 2.495V appears only when the measurement cycle starts for a very short time. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrSqueaky on February 12, 2023, 01:21:47 am
I've discovered a problem with the reference voltage on pin PA3 for my stock LCR-TC2. I was looking at the config.h file of the m-firmware and saw an option for defining the reference voltage so I decided to measure it on my tester but found it was only 45mV.
This is not a problem, but a feature of the tester that you need to know and take into account. In this circuit, the PA3 pin of the MCU is periodically connected to ground (by software), so the reference voltage of 2.495V appears only when the measurement cycle starts for a very short time. ;)

I also have a round GM328A(BGR)2 tester and the reference voltage stays on for a couple of seconds after pressing the test button. I'm pretty sure it wasn't with the LCR-TC2. I overwrote the Chinese firmware so I can't test it anymore to double check
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 12, 2023, 07:13:59 am
I also have a round GM328A(BGR)2 tester and the reference voltage stays on for a couple of seconds after pressing the test button. I'm pretty sure it wasn't with the LCR-TC2. I overwrote the Chinese firmware so I can't test it anymore to double check
If you have a copy of k-firmware installed on your GM328A, then I'm sure the same behavior with Vref was also on your LCR-TC2 with Chinese firmware,which, as madires rightly pointed out, is a modified k-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrSqueaky on February 13, 2023, 05:44:39 am
I finally got the v1.48m firmware working on my LCR-TC2 with hardware SPI.  The pin assignment for the LCD conflicts with the hardware SPI. Tracks need to be rearranged to make a permanent solution. Bit banging works without any need for hardware modification but the output seemed a bit slow. Also, I had to half the hardware SPI speed otherwise I just got a white screen (possibly due to the jumper wires)

Code: [Select]
/* hardware SPI in config_644.h: */
#define SPI_HARDWARE
#define SPI_PORT         PORTB     /* port data register */
#define SPI_DDR          DDRB      /* port data direction register */
#define SPI_PIN          PINB      /* port input pins register */
#define SPI_SCK          PB7       /* pin for SCK */
#define SPI_MOSI         PB5       /* pin for MOSI */
#define SPI_MISO         PB6       /* pin for MISO */
#define SPI_SS           PB4       /* pin for /SS */

/* ST7735 using hardware SPI  in config_644.h: */
#define LCD_PORT         SPI_PORT       /* port data register */
#define LCD_DDR          SPI_DDR        /* port data direction register */
#define LCD_RES          PB0            /* port pin used for /RESX (optional) */
#define LCD_CS           SPI_SS         /* port pin used for /CSX (optional) */
#define LCD_DC           PB1            /* port pin used for D/CX */
#define LCD_SCL          SPI_SCK        /* port pin used for SCL */
#define LCD_SDA          SPI_MOSI       /* port pin used for SDA */

/* set SPI clock rate for hardware SPI display in ST7735.c: */
// SPI.ClockRate = SPI_CLOCK_2X;    /* set clock rate flags */
SPI.ClockRate = 0;    /* set clock rate flags - SPI2X = 0, SPR1 = 0, SPR0 = 0, SCK = fosc/4 */

/* set power management pins in config_644.h: */
#define POWER_PORT       PORTD     /* port data register */
#define POWER_DDR        DDRD      /* port data direction register */
#define POWER_CTRL       PD1       /* controls power (1: on / 0: off) */

#define BUTTON_PORT      PORTD     /* port data register */
#define BUTTON_DDR       DDRD      /* port data direction register */
#define BUTTON_PIN       PIND      /* port input pins register */
#define TEST_BUTTON      PD2       /* test/start push button (low active) */

/* set probe colors to match decal in color.h */
#define COLOR_PROBE_1         COLOR_RED
#define COLOR_PROBE_2         COLOR_YELLOW
#define COLOR_PROBE_3         COLOR_GREEN


Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 13, 2023, 05:51:31 am
I finally got the v1.48m firmware working on my LCR-TC2 with hardware SPI. 
In my experience, for a 1.8" color display at 16-20MHz, there is no particular need for a hardware SPI.
The difference in speed compared to software SPI is not noticeable. For displays with a diagonal of 2.2 inches and above, hardware SPI really gives an increase in the speed of updating the picture, but still not as big as we would like. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on February 19, 2023, 01:06:17 pm
Got this AY-AT kit and it works really well, mounted the ZIF socket in a standard 14 pin DIL socket so I can easily swap it out if need be, the 16Mhz upgrade
was easy-peasy, thanks to all involved with the open source firmware.

Thinking about getting another AY-AT kit, wondering what it would take to make it work with a 3 color e-paper display, i'm guessing it would help a
bit with battery life. https://uk.banggood.com/Waveshare-1_54-Inch-ink-Screen-Module-152x152-Electronic-Paper-SPI-Interface-Yellow-Black-and-White-Three-color-Display-p-1750623.html?imageAb=1&cur_warehouse=CN&rmmds=CategoryElectronicsPop&a=1676811431.4374&DCC=GB&currency=GBP&akmClientCountry=GB (https://uk.banggood.com/Waveshare-1_54-Inch-ink-Screen-Module-152x152-Electronic-Paper-SPI-Interface-Yellow-Black-and-White-Three-color-Display-p-1750623.html?imageAb=1&cur_warehouse=CN&rmmds=CategoryElectronicsPop&a=1676811431.4374&DCC=GB&currency=GBP&akmClientCountry=GB)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 19, 2023, 05:11:27 pm
Recently we've tried an SSD1681 based EPD. It's so slow that it's infeasible. A b/w full display refresh takes several seconds, a three color update even longer. A b/w partial refresh is a bit faster (and blurry), but requires a full refresh after every few partial ones.
Title: Re: $20 LCR ESR Transistor checker project
Post by: py-bb on February 22, 2023, 03:17:33 am
Hi there, I've ordered 2 replacements as unfortunately being without this bit of tat sucks. Before I do the mods any recommendations? I have some diodes I need to test - should I be really careful in which way around they go?
I have a Transistor Tester just like yours where the current limiting feature of U7 failed, but fortunately I avoided roasting D2. Therefore my unit is still generates 30V, but without any current limiting. I went ahead and installed the 2k2 series resistor between the junction of D2/C14 and the K test socket pin. This limits maximum short-circuit current to about 15mA.

IMHO putting in the 2k2 series resistor alone is good enough to prevent anything from smoking.

I continue to recommend replacing U7 too. The 2k2 series resistor protects U7. Even if a direct short is placed from K to A, the 2k2 series resistor keeps U7 safe and happy. After installing a new U7, testing with the 1k resistor should display a “zener voltage” of 5-6V. This indicates U7 is properly limiting the zener test current.

Replacing U7 is out of the question, the boards on mine are not very clean and I've barely used a heatgun before, but I can do the other one.

I think you have made a mistake though, the junction  between D2 and C14 is the K test point so you'd be putting it in parallel with a wire. Do you mean I should knife the trace? That doesn't seem reliable.

Thanks.

Ed in an earlier post you explain this'll require cutting the trace

I can't find that manual link and I'd like to see a picture of your modifications please - I noticed the replacements but not the cut trace in a post you made 3 pages back
Title: Re: $20 LCR ESR Transistor checker project
Post by: py-bb on February 22, 2023, 03:28:29 am
<offtopic>
...I have some diodes I need to test - should I be really careful in which way around they go?
What do you want to measure? Zener voltage? Forward voltage? There are simple ways to measure diodes (Google it). You don't need to risk your tester.
</offtopic>

This is a non-answer but it'd be nice to measure the breakdown voltage (or "the voltage" when using them as voltage regulators) - but mostly I just want a tool I can't break if some wires touch somewhere.

This is why I like hand-held (or differential) voltmeters, you can stick those probes anywhere and it'll be fine (except in weird contrived circumstances which if you bring up I'll point out that if I end up in those conditions something has already gone very wrong - like lack of job equipment & training a person in that situation would actually have)
Title: Re: $20 LCR ESR Transistor checker project
Post by: GraemeG on February 22, 2023, 03:56:38 am
I think you have made a mistake though, the junction  between D2 and C14 is the K test point so you'd be putting it in parallel with a wire. Do you mean I should knife the trace? That doesn't seem reliable.

Thanks.

Ed in an earlier post you explain this'll require cutting the trace

I can't find that manual link and I'd like to see a picture of your modifications please - I noticed the replacements but not the cut trace in a post you made 3 pages back

I don't have a photo to show you but you are correct in your first comment and in your edit. The track from the junction of D2/C14 and the K test point must be cut and the 2K2 resistor soldered in to bridge the cut in the track. This is definitely reliable and it fixes a flaw in this version of the tester.

Almost the first use of my tester was to measure the forward voltage drop of some schottky power diodes. I used the zener test terminals for a slightly higher current than the normal test terminals. In theory U7 is supposed to limit the test current but after just a few tests my unit failed and I discovered D2 totally burned. I don't know what current was flowing during the test but D2 was well past its specs! By inserting the 2K2 resistor the short circuit current is limited to a maximum of about 14mA into a short circuit on the K-A pins. ie. approximately 31V supply divided by 2200 ohms = 14.1mA
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on February 22, 2023, 11:47:34 am
<offtopic>
...I have some diodes I need to test - should I be really careful in which way around they go?
What do you want to measure? Zener voltage? Forward voltage? There are simple ways to measure diodes (Google it). You don't need to risk your tester.
</offtopic>

This is a non-answer but it'd be nice to measure the breakdown voltage (or "the voltage" when using them as voltage regulators)
As I said, Google it. Like Google 'measuring zener voltage' or 'testing zener diodes'
Title: Re: $20 LCR ESR Transistor checker project
Post by: mastershake on February 25, 2023, 07:01:51 am
so out of the insane amount of various clones out there can so done simply suggest one that works and will allow firmware upgrades if need be? I've been trying to get through this thread but with one eye down reading for me is a lot slower than it used to be. I'm about 1/4 way into the thread but think maybe I should have started on 330 and went backwards. I'm looking for really the best of the clones I guess but one I can upgrade or will that require changing the chip regardless. thank you in advance and I def appreciate any help or info. I'm heading back in for two weeks to the hospital for more cancer stuff and I'd love to get one ordered before going in. hopefully lots of boxes waiting for me when I get out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 25, 2023, 01:34:49 pm
Which clone to get is a common question and you'll find the answer quite often on the last 10 pages. Be aware that some clones currently come with an alternative MCU not supported by the OSHW firmwares.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mastershake on February 26, 2023, 07:13:19 am
Thats why I was asking does anyone have a recc seller or one you have recently bought that was legit? I just don't want to go through a bunch trying to get a good one. any AliExpress or Amazon etc link anyone could share if you know you got a legit one recently?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 26, 2023, 07:22:20 am
mastershake,so this is the problem that no one will give you a 100% guarantee that the seller will send you the LEGIT device.Because in most cases, the seller has no idea about the contents of the goods.Today one person received a legitimate product, and tomorrow another person will receive an "illegal" product from the same seller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mastershake on February 26, 2023, 08:26:07 am
is there a certain board layout that one would want vs the rest of them at least? that sucks about not being able to get a legit one from any one seller.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on February 27, 2023, 11:36:46 am
Right now from my experience, it seems the best option is to get the self build kit, that way you can be sure of getting a component tester you can easily self repair, mod and upgrade the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on February 27, 2023, 06:42:20 pm
Right now from my experience, it seems the best option is to get the self build kit, that way you can be sure of getting a component tester you can easily self repair, mod and upgrade the firmware.
I recently purchased one of these kits. It is a "through-hole" PC board  using a DIP package ATmega328P mounted in a socket.

It had just one significant issue: The 680 ohm and 470k ohm "probe resistors" supplied with the kit were out of spec.

Specifically one 680 ohm resistor measured 691 ohms compared to the other two (675 and 676 ohms). The error is 1.6%
Unfortunately this prevented my tester from entering the "self-test" mode. It failed to detect that the probes had been shorted to start the self-test.

Re-reading this topic revealed these frequent instructions from the experts:

     "make sure your 680 ohm and 470k resistors are well-matched within 0.1%."

For a "quick fix" I put a 33k resistor in parallel with the out-of-spec 691 ohm resistor. The result is 677 ohms.
This immediately permitted "self-test" to operate.
My tester now works perfectly.

I do recommend these kits for people who are comfortable soldering "through-hole" PC boards.
There is no chance of getting a "fake" DIP package ATmega328P because nobody but Atmel/Microchip makes them.
Also having the MCU in a socket makes firmware upgrades and experimentation quick and easy.
And it is feasible to replace those crummy original resistors with ultra-high precision resistors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on February 27, 2023, 07:13:21 pm
Moreover, if you kill the MCU with a charged capacitor,
you can in this case simply replace the MCU.  :horse:
Title: Re: $20 LCR ESR Transistor checker project
Post by: GraemeG on February 27, 2023, 11:25:16 pm
Right now from my experience, it seems the best option is to get the self build kit, that way you can be sure of getting a component tester you can easily self repair, mod and upgrade the firmware.

Alex did your kit come with the clear plastic case or does this need to be ordered separately?
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on February 28, 2023, 10:04:01 am
My kit didn't come with case, I ordered it later. There are 2 types of plastic clear case, I got the angled one with space for the 9v battery underneath.
It's worth mounting the ZIF socket in a regular DIL socket since it raises a bit so you can operate the handle better.

I flipped around the 2 bottom terminals underneath so I could easily get at the protection diode if I ever need to swap it out.
I tested out all the resistors before I assembled the kit and found 4 were the wrong value and couldn't be used, not a big deal as I had the missing values
in my spares box.

I mounted the power connector for the battery underneath so making the wire routing easier. I also got a spare Atmega so I could program it on
a breadboard. The kit is worth it just for the PCB and the MCU alone.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on March 01, 2023, 03:19:07 pm
@ GraemeG.

Yes that case works fine.
I have made an modification to acces the SMD Pad
and easier to move the handle of the Zif-socket.
See post 2673
Title: Re: $20 LCR ESR Transistor checker project
Post by: GraemeG on March 01, 2023, 10:32:40 pm
Thanks Alex and Pukker. I hadn't seen the angled case before and I like the idea of a built in 9V battery.

I also think I would modify the case as you did Pukker although I don't do much SMD work. Perhaps lifting the ZIF socket with a normal DIL socket is a simpler option although I would prefer soldered connections. Has anyone had problems with the ZIF or the MCU being mounted in sockets? The contact resistance should be low but I wonder if it could affect any of the measurements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2023, 12:26:12 pm
I'd recommend to use precision sockets. Cheap ones tend to cause connection problems after a while, especially when the ZIF is a bit wiggly (no tight fit allows movement of the ZIF).
Title: Re: $20 LCR ESR Transistor checker project
Post by: davidut5 on March 03, 2023, 11:15:05 am
Got new tester lcr-tc1, first measurement capacitor in zener diode kaa probes got some charge then moved to 1-2, tester got damaged.
Bought new mega328PB, 328p not available, read about pin 3 and 6, pin 6 not connected and pin 3 connected to ch340n pin 7.
5v ok when mega328 removed, but when in place after pushing start it gets very hot in short time and have to remove the battery to stop. No software on yet, but getting hot i think is not software related. Cut the circuit to pin 3 still getting hot. Resistance on 6v8 diode is 400k.
And about firmware, was looking for original, nothing fancy just need it to work. Managed to repair another lcr t4, replacing the mega328p, using avrdudes but for this did not find original firmware to download, just modified.
I am confused, board gives power only on pins 18(gnd) and 19(vcc), but datasheet say pins 3 and 4! I think the chip has wrong markings on it, probably on purpose. there is also no oscillator on board. What kind of chip this could be? Atmega3208 maybe?
In the picture not 100% but the one on the right is from tc1 and the left from t4.
Thank you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: smg on March 03, 2023, 12:21:23 pm
Delivered my T7 with a clone Mega328,
pcb similar to LCR-TC1(2) from the file TableClonesEN.pdf by indman@EEVblog
https://yadi.sk/d/yW8xa5NJgUo5z


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 03, 2023, 03:24:19 pm
I am confused, board gives power only on pins 18(gnd) and 19(vcc), but datasheet say pins 3 and 4! I think the chip has wrong markings on it, probably on purpose. there is also no oscillator on board.

Most likely the MCU the clone came with is an APT32F172K8T6 with fake ATmega marking. Sadly we see more and more of those.

Title: Re: $20 LCR ESR Transistor checker project
Post by: davidut5 on March 03, 2023, 03:57:16 pm
Very disappointing, the mega328 was almost 1/4 the price of the tc1 tester and now not getting it to work any time soon!
I get it there is no firmware available for it yet, or the chip not available to buy!
Clone tester with a clone chip from a clone!  :-DD
Hope the mega328pb is still ok, to keep for the t4, just in case another charged cap comes around!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on March 03, 2023, 09:33:56 pm
What kind of chip this could be? Atmega3208 maybe?
I have exactly the same circuit board and mine has a APT32F172K8T6 on it.
So I guess yours is a APT32F172K8T6 too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on March 04, 2023, 06:27:31 pm
I'd recommend to use precision sockets. Cheap ones tend to cause connection problems after a while, especially when the ZIF is a bit wiggly (no tight fit allows movement of the ZIF).

This is what the Hiland M644 uses, pity you can't get a through-hole kit or PCB for this M644 layout  ;-)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MrSqueaky on March 05, 2023, 01:18:19 am
Very disappointing, the mega328 was almost 1/4 the price of the tc1 tester and now not getting it to work any time soon!
I get it there is no firmware available for it yet, or the chip not available to buy!
Clone tester with a clone chip from a clone!  :-DD
Hope the mega328pb is still ok, to keep for the t4, just in case another charged cap comes around!

A 5V Arduino Pro Mini glued on to the nice big ground plane and lots of enamelled jumper wires and it'll be good as new  :)

There seems to be a ~US$5 price difference between the LCR-TC1 and LCR-TC2 on Aliexpress. I'm guessing that covers the price of a real Atmel chip
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 05, 2023, 02:52:02 am
There seems to be a ~US$5 price difference between the LCR-TC1 and LCR-TC2 on Aliexpress. I'm guessing that covers the price of a real Atmel chip
BINGO! Spot-on! :-+  :clap:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Thelmos on March 07, 2023, 08:15:55 pm
I just received a LCR-TC2 from China...

I didn't like the first test, short-circuiting the three pins didn't launch the calibration, it directly measures the short-circuit resistance, from what I've read in this thread this may be because the resistors are out of spec (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4726172/#msg4726172 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4726172/#msg4726172)).

The manual doesn't even mention how to do the calibration.

I have also done the test that @elecdonia mentioned in https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4692413/#msg4692413 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4692413/#msg4692413), results: 12.68V  :-//

Seeing the board, my fears have come true...

Title: Re: $20 LCR ESR Transistor checker project
Post by: MrSqueaky on March 08, 2023, 02:32:00 am
I just received a LCR-TC2 from China...

Looks like cost cutting has finally caught up to the LCR-TC2 (PCB labelled T7-PLUS V2.0) or it a knock off. What markings are on the MCU? It is not a ATMega324 (pin count wrong) and not a ATMega328P (power pins don't match). Some sort of clone chip.

The circuit for the zener diode voltage appears OK (U7, R18, R19, L2, D4, C15). R20 should limit the current. The voltage between D4 and R20 should be around 27V

The 6V8 TVS diode has been omitted. Smaller crystal. Configurable power-off time is back. There appears to be a little push button (?) in the bottom left labelled "OFF" for manual shutoff? Strange
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 08, 2023, 03:15:33 am
I just received a LCR-TC2 from China...  I didn't like the first test, short-circuiting the three pins didn't launch the calibration, it directly measures the short-circuit resistance, from what I've read in this thread this may be because the resistors are out of spec Seeing the board, my fears have come true...
Your LCR-TC2 is likely to contain the LGT8F328P MCU chip. This is a Chinese “?clone?” of the Atmel ATmega328P MCU. However the pinout is different. Also the architecture is sufficiently different enough to require a rewrite of the existing TransistorTester firmware. Check out these other posts for more info:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4316005/?topicseen#msg4316005 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4316005/?topicseen#msg4316005)

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4606612/?topicseen#msg4606612 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4606612/?topicseen#msg4606612)

As for the failure of your tester to enter the “self test” you should measure the resistance of the three 680 ohm resistors which connect from the MCU to test terminals 1, 2, and 3. These 3 resistors must be matched to each other within 0.1%. I fixed a similar issue by adding a parallel resistor to one of the 680 ohm resistors which was above its proper value by +1.8%

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4726172/?topicseen#msg4726172 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4726172/?topicseen#msg4726172)

Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 09, 2023, 03:47:34 pm
Delivered my T7 with a clone Mega328, pcb similar to LCR-TC1(2) from the file TableClonesEN.pdf by indman@EEVblog
https://yadi.sk/d/yW8xa5NJgUo5z (https://yadi.sk/d/yW8xa5NJgUo5z)
The MCU chip in your LCR-T7 is the LGT8F328P made by a Chinese company known as “Logic Green.” It is somewhat similar to the Atmel ATmega328P, but it certainly isn’t a direct replacement. First of all the pinout is different. More important, its architecture and software are considerably different. Furthermore it doesn’t support the Atmel “ICSP” (aka “ISP”) programming interface.

Here are some related EEVBlog topics discussing the LGT8F328P:

https://www.eevblog.com/forum/microcontrollers/arduino-pro-mini-two-copies-have-different-sleep-currents/msg3184622/#msg3184622 (https://www.eevblog.com/forum/microcontrollers/arduino-pro-mini-two-copies-have-different-sleep-currents/msg3184622/#msg3184622)

https://www.eevblog.com/forum/projects/anyone-here-interested-in-the-logic-green-avrs-lgt8f328p/msg2717650/#msg2717650 (https://www.eevblog.com/forum/projects/anyone-here-interested-in-the-logic-green-avrs-lgt8f328p/msg2717650/#msg2717650)

https://www.eevblog.com/forum/microcontrollers/lgt8f328p-clone-of-atmega328-with-lots-of-extras-anybody-use-them/ (https://www.eevblog.com/forum/microcontrollers/lgt8f328p-clone-of-atmega328-with-lots-of-extras-anybody-use-them/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 09, 2023, 03:56:08 pm
Very disappointing, the mega328 was almost 1/4 the price of the tc1 tester and now not getting it to work any time soon!  I get it there is no firmware available for it yet, or the chip not available to buy!
Clone tester with a clone chip from a clone!  :-DD

Hope the mega328pb is still ok, to keep for the t4, just in case another charged cap comes around!
At least the manufacturer of this particular Transistor Tester was ethical enough to keep the original APT32F172K8T6 label on the MCU chip.

A couple of months ago I received a Transistor Tester where the APT32F172K8T6 device had been deliberately re-labeled as Atmel ATmega328P.  :wtf:  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 09, 2023, 10:33:58 pm
Let's say we received a new Chinese T7 clone, a TQFP32 MCU without any marks @16MHz. Is there any way to make an educated guess on what knock-off it can be, LGT8F328P or other?
If there is a crystal mounted on the PC board next to the MCU chip:   Then MCU is Lucky Green LGT8F328P

If there is no crystal on the PC board:   Then MCU is APT32F172K8T6. Evidently this MCU has internal clock oscillator

Note: During the past several months I have seen and tested several recently manufactured  “LCR-x” Transistor testers.
None of these units with the MCU chip in a 32-pin TQFP package contain the Atmel ATmega328P MCU.
However, some of these 32-pin MCU chips did have realistic looking (counterfeit) ATMega328P  labels laser engraved on them.

I recently bought one LCR-x unit with a real ATmega324 in a 44-pin TQFP package. It cost about $9 USD more than the units containing imitation 32-pin MCU chips. To the best of my knowledge none of the low-cost Chinese MCU chips come in 44-pin packages (yet).  So if the MCU has 44-pins it is likely to be a real Atmel ATmega324.
Title: Re: $20 LCR ESR Transistor checker project
Post by: davidut5 on March 09, 2023, 10:45:24 pm
Yes, i guess 328p does not support infrared and maybe zenner test. That's why they use the 44 pin 324, but now they made their own ic. This was the cheapest lcr-1 tester i can get in my country, probably the other ones had the 324 atmel. Did not think it would be different.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 10, 2023, 07:39:04 am
You can have the IR receiver/decoder (via the three probes) and the Zener check (usually PC3) with an ATmega328 without any problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on March 10, 2023, 06:52:23 pm
If  I had a custom PCB made using AY-AT design but altered the board substituting the ATMega328 with a ATmega1284p package, it should just work right?
assuming I compile the the firmware for the ATmega1284p and I would have 4 times the flash?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 10, 2023, 07:39:53 pm
Yep! But you could make some small changes to improve the display performance:
- move the rotary encoder to dedicated pins
- go for hardware SPI for the display
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 10, 2023, 10:12:40 pm
If  I had a custom PCB made using AY-AT design but altered the board substituting the ATMega328 with a ATmega1284p package, it should just work right?
assuming I compile the the firmware for the ATmega1284p and I would have 4 times the flash?
I've been thinking about the same thing. In fact there are ATmega644 and ATmega1284 devices sitting on my workbench right now. They are housed in 40-pin DIP packages.

I plan to scratch-build a Transistor Tester on a "perma-proto" board with a 40-pin MCU socket.

Another of my ideas is to design a separate analog section to interface with the 3 test pins. 
It will have a high-resolution A-D converter and dedicated low-resistance drivers for the test pins.
All signals to/from the MCU will then be logic level. This way it won't matter whether the MCU operates at 5V or 3.3V. 
Eventually I might make the test voltages/currents for the 3 test pins programmable: Ideally 0-100V and 0-2A.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on March 11, 2023, 02:23:23 pm
To conclude, the fix is:
1) Cut the PC board foil leading to pin K and then connect 2K2 resistor from junction of D2 and C14 to pin K,
Thank you!
There isn't much space for a 1206 SMD, but it works.
This is my first attempt at SMD soldering.  :-[

Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on March 12, 2023, 09:11:04 am
A question for Madires:
I had a device with a seemingly working Rohm 1SR159-200 diode rectifying the output from a switch mode transformer but it provided unexpected low output voltage.
In the end I found that the diode had failed in such a way that it became a regular diode, not a ultra fast diode!
I first replaced it with a UF4007 and it got me much closer to the expected output voltage.
So I bought a even faster diode (Diotec ES1D) that should exceed the originals specifications on paper and I got the expected output voltage!
My question is if this type of testing (speed of the diode) could be implemented in the transistor tester?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 12, 2023, 09:25:23 am
A question for Madires:
I had a device with a seemingly working Rohm 1SR159-200 diode rectifying the output from a switch mode transformer but it provided

And what test results do you see now with this diode on a transistor tester? What is the CpF? What are the results compared to a serviceable ES1D?  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on March 12, 2023, 10:01:05 am
And what test results do you see now with this diode on a transistor tester? What is the CpF? What are the results compared to a serviceable ES1D?  :)
The bad Rohm 1SR159-200 with trr value from datasheet: <50ns (23ns typical)
Uf=570mV
9.3pF - 3.6pF @ 0 - 5V
Ir=0.18µA

A new Diotec ES1D with trr value from datasheet: <15ns
Uf=541mV
24pF - 15pF @ 0 - 5V

But to do a proper test I should desolder one of the other Rohm diodes from the unit and measure those, since the Diotec has better specs in the datasheet.
But first I want to hear what madires thinks too :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on March 12, 2023, 10:20:43 am
If  I had a custom PCB made using AY-AT design but altered the board substituting the ATMega328 with a ATmega1284p package, it should just work right?
assuming I compile the the firmware for the ATmega1284p and I would have 4 times the flash?

I recall years ago seeing one of the first avr transistor tester prototyped on a dip atmega32a. i think the page is only accessible on the web archive. however the support for that mcu seems to not be listed any more.
If you want any help in designing the pcb and keeping it open source i can offer it. I'd like it to have an isp header, something that is missing from most designs. If nothing else i can check for mistakes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 12, 2023, 10:57:41 am
My question is if this type of testing (speed of the diode) could be implemented in the transistor tester?

The ATmega's slow ADC plus some processing time would limit that measurement to about 30µs, I'd guess. The reverse recovery time of a classic 1N400x can be somewhere between 30 and 2µs (UF400x: 50/75ns). So it wouldn't help much.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on March 12, 2023, 11:50:04 am
The reverse recovery time of a classic 1N400x can be somewhere between 30 and 2µs (UF400x: 50/75ns). So it wouldn't help much.
There is no need to add anything, both authors clearly show the dependence of the diode capacitance on its speed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 12, 2023, 12:09:51 pm
The reverse recovery time of a classic 1N400x can be somewhere between 30 and 2µs (UF400x: 50/75ns). So it wouldn't help much.
There is no need to add anything, both authors clearly show the dependence of the diode capacitance on its speed.
Then why is the lower capacitance 1SR159-200 diode not working properly?:)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on March 12, 2023, 12:14:44 pm
Then why is the lower capacitance 1SR159-200 diode not working properly?:)
Because, Ir=0.18µA
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 12, 2023, 12:19:04 pm
Then why is the lower capacitance 1SR159-200 diode not working properly?:)
Because, Ir=0.18µA
According to the datasheet 1SR159-200, the allowable Reverse Ir can reach 10µA
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on March 12, 2023, 12:22:55 pm
My question is if this type of testing (speed of the diode) could be implemented in the transistor tester?

The ATmega's slow ADC plus some processing time would limit that measurement to about 30µs, I'd guess. The reverse recovery time of a classic 1N400x can be somewhere between 30 and 2µs (UF400x: 50/75ns). So it wouldn't help much.
Thank you for the explanation madires!

Yuriy_K: I desoldered a working Rohm 1SR159-200 diode now but unfortunately it measures almost identical to the bad one:
Uf=545mV
10pF - 3.5pF @ 0 - 5V
Ir=0.20µA

I thought it could be a nice addition to measure the reverse recovery speed (trr) since this was a pretty tricky failure mode, but if the ADC is too slow then that is not possible of course...
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 12, 2023, 12:26:18 pm
Per Hansson,What operating voltage is present on this diode in the circuit?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on March 12, 2023, 12:30:58 pm
Per Hansson,What operating voltage is present on this diode in the circuit?
The output from the transformer is 50v p-p at ca 100kHz, see attached screenshot.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 12, 2023, 12:38:34 pm
The operating voltage exceeds the test voltage by 10 times, so it has been repeatedly repeated in this and other topics that this tester cannot provide a 100% probability of detecting all faults. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on March 12, 2023, 04:27:49 pm

Yuriy_K: I desoldered a working Rohm 1SR159-200 diode now but unfortunately it measures almost identical to the bad one:
Uf=545mV
10pF - 3.5pF @ 0 - 5V
Ir=0.20µA

I thought it could be a nice addition to measure the reverse recovery speed (trr) since this was a pretty tricky failure mode, but if the ADC is too slow then that is not possible of course...

I made a comparison of similar characteristics of US1M and 1SR159-200. Compare for yourself, I can’t understand where Ir=0.18µA  comes from at 5v. Probably problems with the diode, it is a pity that there is no unused diode to compare with the used ones.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on March 12, 2023, 06:53:24 pm
I made a comparison of similar characteristics of US1M and 1SR159-200. Compare for yourself, I can’t understand where Ir=0.18µA  comes from at 5v. Probably problems with the diode, it is a pity that there is no unused diode to compare with the used ones.
Notice how there is very little difference of reverse current at 200v vs the minimum the datahseet shows at 50v.
So if we extrapolate down to 5v it is easy to see how the reverse current value could still be valid.

The operating voltage exceeds the test voltage by 10 times, so it has been repeatedly repeated in this and other topics that this tester cannot provide a 100% probability of detecting all faults. ;)
Sure, but it still provides relevant data, I'm sure it could test reverse recovery time too even at that low voltage.
But as madires says if the speed of the ADC is not enough that will limit the lowest trr value we can see.
And just to provide a different way to visualize it:
Diotec ES1D in-circuit output voltage: 17.87v
Rohm 1SR159-200 in-circuit output voltage: 17.83v
Diotec UF4007 in-circuit output voltage: 17.30v
Bad Rohm 1SR159-200 in-circuit output voltage: 14.4v
Title: Re: $20 LCR ESR Transistor checker project
Post by: 9voltbrain on March 12, 2023, 08:00:36 pm
Can anyone chime in on the differences between the LCR-T7 and LCR-T4? I'm mostly interested in getting some ballpark measurements on the inductors I have lying around here. As long as I get +/- 20uH I'm happy. I don't want to get the LCR-T7 because of the built in rechargeable battery. It's just annoying to me having to keep it charged and dealing with it going bad eventually. Do you have to recalibrate the T4 every time you take the 9v battery out?

There is also another meter available from where I usually buy stuff called M162, but I can't find any info on it. Anyone tried it? It's like 3x the price of the other ones. Picture below.
(https://www.electrokit.com/uploads/productimage/41019/41019116-2-2-600x450.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 12, 2023, 08:54:43 pm
Have you looked at indman's table of ctester clones (https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 13, 2023, 01:09:27 am
There is also another meter available from where I usually buy stuff called M162, but I can't find any info on it. Anyone tried it? It's like 3x the price of the other ones. Picture below.
That is a gorgeous display. Someone with talent designed it and wrote the code for it.

Regarding testing small inductors, have you considered the LC100-A?
It measures L and C only (nothing else). I’ve had one for years. It is an excellent companion for a Transistor Tester because it uses a totally different measurement process. I found that the LC100-A does a great job measuring L <10uH and C <50pF. Here’s a topic that discusses them:

https://www.eevblog.com/forum/testgear/lc100-a-a-precise-lc-meter-for-3-75$/msg4599424/#msg4599424 (https://www.eevblog.com/forum/testgear/lc100-a-a-precise-lc-meter-for-3-75$/msg4599424/#msg4599424)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on March 13, 2023, 07:18:49 am
The M162 is not a transistor checker.
You might want to go here:
https://www.eevblog.com/forum/testgear/new-jyetech-m162-lcr-meter-(april-2022)/msg4136254/#msg4136254 (https://www.eevblog.com/forum/testgear/new-jyetech-m162-lcr-meter-(april-2022)/msg4136254/#msg4136254)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on March 13, 2023, 12:31:22 pm
As long as I get +/- 20uH I'm happy.
...
Do you have to recalibrate the T4 every time you take the 9v battery out?
Three years ago I made a firmware for T4 for another forum. In it, to measure small inductances and capacitances, it is necessary to replace the crystal with 16 MHz. Since then, much of the software has changed and expanded. In the archive, the changes are in New, but this firmware is not tested, I do not have T4.
The calibration is retained when the battery is replaced.

Examples of measuring small inductances are in my posts.

Title: Re: $20 LCR ESR Transistor checker project
Post by: hojnikb on March 13, 2023, 01:47:13 pm
hello; new here with these whole cheap LCR tester... Which one should one buy these days? There seems to be lots of different versions available (like TC1, TC2, T7 etc)....

Is there a list of all these clones and pros/cons of each one?  ^-^
Title: Re: $20 LCR ESR Transistor checker project
Post by: hojnikb on March 13, 2023, 01:54:56 pm
hello; new here with these cheap LCR testers... Which should one buy these days? There seems to be lots of different versions available (like TC1, TC2, T7 etc)....

Is there a list of all these clones and pros/cons of each one?  ^-^
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 13, 2023, 04:25:30 pm
Feliciano posted a link to a list just four posts earlier. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on March 13, 2023, 04:50:02 pm
Feliciano posted a link to a list just four posts earlier. ;)
Yes, but I'm not sure how current this list is.
There are TC1 and T7 with APT32F172K8T6 in them, which are not listed there.
It's difficult to say what you're actually getting.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 13, 2023, 05:14:33 pm
Feliciano posted a link to a list just four posts earlier. ;)
Yes, but I'm not sure how current this list is.
There are TC1 and T7 with APT32F172K8T6 in them, which are not listed there.
It's difficult to say what you're actually getting.

Sorry, but I'm personally already tired of sorting out the varieties of Chinese shit that they have been putting on the market lately.
Maybe someone else can do it better than me.  >:D
If you want to get a real product, then the best option is to assemble the tester with your own hands from the very beginning according to the original author's project, using high-quality components.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on March 13, 2023, 09:00:36 pm
Feliciano posted a link to a list just four posts earlier. ;)
Yes, but I'm not sure how current this list is.
There are TC1 and T7 with APT32F172K8T6 in them, which are not listed there.
It's difficult to say what you're actually getting.

Sorry, but I'm personally already tired of sorting out the varieties of Chinese shit that they have been putting on the market lately.
Maybe someone else can do it better than me.  >:D
If you want to get a real product, then the best option is to assemble the tester with your own hands from the very beginning according to the original author's project, using high-quality components.
That gets said a lot but it's hardly necessary. as others have said there are no fake dip mcu. so if i was looking for one i'd chose something that can be hooked to a 9v square battery, ( the 18650 3.7v cells may not work with all components) although there's not always a foto of the dip ic, you usually get a foto of the back of the pcb. make sure you get one with two rows of 14 pins, which is the dip 28 package of the atmega328p. I just checked a chinese site and although there's a lot of fakes, the dip pcbs are easy to see.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 14, 2023, 12:26:21 am
Stated another way: “You get what you pay for.”

Unfortunately all of the currently available cheap LCR-style Transistor Testers which are housed inside cream-colored plastic cases are garbage. Please do not buy any of them. 

Starting a bit over a year ago the Chinese manufacturers of these LCR-style Transistor Testers abandoned the (original design) Atmel ATmega324 MCU chip in favor of the (much cheaper) APT32F172K8T6 or LGT8F328P MCU chips. However these substitute MCU chips cannot run any of the (excellent quality) open-source Transistor Tester firmware. Unfortunately the non-upgradable firmware which comes in these “cheap” LCR-style units barely works at all.

These alternate MCU chips are made by smaller Chinese semiconductor manufacturers. They cost only about $0.25 USD each. In contrast a genuine Atmel/Microchip ATmega324 MCU now sells for $5-9 USD each as a bare IC chip. Therefore it is impossible for anyone to sell an LCR-type Transistor Tester containing the Atmel ATmega324 MCU for <$25 USD.

I did succeed at purchasing a model LCR-TC2 “V2.3E” Transistor Tester recently which contains the proper (original design) Atmel ATmega324 MCU but it cost me nearly $40 USD. Although more expensive, this unit fully supports the open-source Transistor Tester firmware, both k- and m- variants. This makes it well worth the extra cost. More details may be found in the following posts:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4653559/#msg4653559 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4653559/#msg4653559)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4687568/#msg4687568 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4687568/#msg4687568)
https://www.eevblog.com/forum/testgear/lcr-t7-tester-reliable/msg4603333/#msg4603333 (https://www.eevblog.com/forum/testgear/lcr-t7-tester-reliable/msg4603333/#msg4603333)
https://www.eevblog.com/forum/testgear/lcr-t7-tester-reliable/msg4606021/#msg4606021 (https://www.eevblog.com/forum/testgear/lcr-t7-tester-reliable/msg4606021/#msg4606021)

Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 14, 2023, 02:34:16 am
I like DIP because of the ease of swapping out the chip. What would be the advantage of an ATmega324 over ATmega328 to pay a premium for a tester based on it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 14, 2023, 04:50:58 am
I like DIP because of the ease of swapping out the chip. What would be the advantage of an ATmega324 over ATmega328 to pay a premium for a tester based on it?
1) Some of us want a Transistor Tester which comes in an attractive “toolbox-friendly” finished plastic case with a self-contained USB rechargeable battery, rather than an unenclosed PC board with a loose 9V battery dangling by its cable.

2) High-quality LCR-style units contain the ATmega324 MCU in a 44-pin TQFP package. In contrast, “cheap” LCR-style units have 32-pin MCU chips which probably aren’t the Atmel ATmega328P. However there aren’t yet any alternative “cheap” MCU chips which come in 44-pin TQFP packages. Therefore if a Transistor Tester contains a 44-pin TQFP MCU chip this indicates the MCU is likely to be an authentic Atmel ATmega324, rather than some dodgy $0.25 USD MCU with unknown architecture running poorly designed Chinese firmware which cannot be upgraded.

3) Transistor Testers with ATmega324 can be upgraded to ATmega644 to get twice as much flash (64k vs. 32k). This enables activating all of the advanced features offered by some versions of the open-source Transistor Tester software. The ATmega324 and ATmega644 have the same physical dimensions and pinout.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hojnikb on March 14, 2023, 06:21:02 am
Feliciano posted a link to a list just four posts earlier. ;)

Thank you, i've totally missed it. I see there are numerious variations and with different MCUs  :-/O
Title: Re: $20 LCR ESR Transistor checker project
Post by: hojnikb on March 14, 2023, 06:37:38 am
Stated another way: “You get what you pay for.”

Unfortunately all of the currently available cheap LCR-style Transistor Testers which are housed inside cream-colored plastic cases are garbage. Please do not buy any of them. 

Starting a bit over a year ago the Chinese manufacturers of these LCR-style Transistor Testers abandoned the (original design) Atmel ATmega324 MCU chip in favor of the (much cheaper) APT32F172K8T6 or LGT8F328P MCU chips. However these substitute MCU chips cannot run any of the (excellent quality) open-source Transistor Tester firmware. Unfortunately the non-upgradable firmware which comes in these “cheap” LCR-style units barely works at all.

These alternate MCU chips are made by smaller Chinese semiconductor manufacturers. They cost only about $0.25 USD each. In contrast a genuine Atmel/Microchip ATmega324 MCU now sells for $5-9 USD each as a bare IC chip. Therefore it is impossible for anyone to sell an LCR-type Transistor Tester containing the Atmel ATmega324 MCU for <$25 USD.

I did succeed at purchasing a model LCR-TC2 “V2.3E” Transistor Tester recently which contains the proper (original design) Atmel ATmega324 MCU but it cost me nearly $40 USD. Although more expensive, this unit fully supports the open-source Transistor Tester firmware, both k- and m- variants. This makes it well worth the extra cost. More details may be found in the following posts:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4653559/#msg4653559 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4653559/#msg4653559)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4687568/#msg4687568 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4687568/#msg4687568)
https://www.eevblog.com/forum/testgear/lcr-t7-tester-reliable/msg4603333/#msg4603333 (https://www.eevblog.com/forum/testgear/lcr-t7-tester-reliable/msg4603333/#msg4603333)
https://www.eevblog.com/forum/testgear/lcr-t7-tester-reliable/msg4606021/#msg4606021 (https://www.eevblog.com/forum/testgear/lcr-t7-tester-reliable/msg4606021/#msg4606021)

Looks like LGT8F328P could be a better bet, since someone actually tried to port alternative firmware to it
https://github.com/DurandA/transistor-tester-lgt328p (https://github.com/DurandA/transistor-tester-lgt328p)

Anyone bought and used this MCU with this firmware? Is it even possible to know if you're getting LGT8F328P or APT32.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 14, 2023, 01:10:35 pm
P.S. Regarding the table of clones: There are so many variants lately, and the totally chinese ones are not currently supported by OSHW, so there will be not so useful to say "the same box, but with an MCU not currently supported".
Title: Re: $20 LCR ESR Transistor checker project
Post by: hojnikb on March 14, 2023, 01:24:46 pm
  • We already had a short discussion about DurandA approach. You can go back to the posts of July 23, 2022 of this thread
  • Unless the vendor shows an internal photo (and even in that case we cannot be 100% certain), you cannot know for sure what you're going to get untill you have it in your hands. For instance, last July I bought one T1 and one T7 from Amazon, for $20+ each, from different sellers. One was the real ATmega, the other was a 32pin clone

Guess i'll have to roll the dice and see what i get. It's cheap though, so it won't matter that much.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mcgyvr81 on March 16, 2023, 03:39:04 pm
Hello folks,

I just found out about this thread on eevblog forums about Markus' and Karl-Heinz' Testers recently.

After reading about the latest batches of LCR-TC1/TC2 containing counterfeit or clone MCUs, I tried not to head down the "Aliexpress Alley" - so I purchased a T7-Tester that is locally branded by german distributor Joy-It. I attached some pictures - as it seems, this still is "the real deal" on the inside?

This one was purchased from reichelt.de
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 16, 2023, 04:36:25 pm
Yep, that should be a genuine ATmega328. If you want to run the m-firmware the settings are listed in the Clones file. IIRC, the STC15L104W of that model doesn't need to be reprogrammed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Specmaster on March 17, 2023, 01:34:41 pm
I can thoroughly recommend one of these units with the case. I've had mine now for a number of years and is the same board as this uses, there are other slight variations of the eBay for sale, but I can't vouch for those, but this one has given my very good service and is certainly reasonably accurate, checking it against bigger 4 lead devices.

https://www.ebay.co.uk/itm/155087140184 (https://www.ebay.co.uk/itm/155087140184)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 17, 2023, 05:42:04 pm
…I purchased a T7-Tester that is locally branded by german distributor Joy-It. I attached some pictures - as it seems, this still is "the real deal" on the inside?
This one was purchased from reichelt.de
This unit should be perfect for upgrading to current OSHW firmware, either k- or m- style. To the best of my knowledge all ATmega328P chips in 28-pin DIP packages are genuine. And because it is mounted in a socket it will be very easy to change if you wish to do so.

Another good feature about this PC board is that it has pads for installing the standard 6-pin Atmel ISP programming header. This permits uploading firmware through an AVR-ISP programmer without removing the MCU from the PC board. I use “Arduino as ISP” for this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 17, 2023, 06:28:46 pm
I can thoroughly recommend one of these units with the case. I've had mine now for a number of years and is the same board as this uses, there are other slight variations of the eBay for sale, but I can't vouch for those, but this one has given my very good service and is certainly reasonably accurate, checking it against bigger 4 lead devices.
https://www.ebay.co.uk/itm/155087140184 (https://www.ebay.co.uk/itm/155087140184)
There is one major issue with these Transistor Testers which have their MCU in a 32-pin TQFP package (8 pins on each of the 4 sides of the package).

     These days there are 3 totally different 32-pin TQFP package MCU chips which may appear in Transistor Testers:

Atmel ATmega328P   — this is the MCU specified by the original OSHW Transistor Tester project. However its price has increased from $3 USD to $9-10 USD, so the low-cost Chinese vendors stopped using it.

Logic Green LGT8F328P — This is a Chinese MCU which costs <$1 USD. It is said to be “somewhat” similar to the original Atmel AT328P. But unfortunately several of its pins have different functionality. Therefore a Transistor Tester containing LGT8F328P cannot easily have its MCU replaced by the Atmel ATmega328P. Also the LGT8F328P has substantially different internal features, which means existing OSHW firmware won’t work without considerable modification.

Aptchip APT32F172K8T6.  — Another Chinese MCU which costs <$1 USD. It has nothing at all in common with the original Atmel ATmega328P. The pinout is totally different. Also the internal MCU architecture is totally different.

Warning: Some of these $1 USD Chinese MCU chips have been deliberately mislabeled as “Atmel ATmega328P.”

More discussions about this are found here:
   https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4613737/?topicseen#msg4613737 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4613737/?topicseen#msg4613737)
   https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/?topicseen#msg4610314 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/?topicseen#msg4610314)
   https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4600771/#msg4600771 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4600771/#msg4600771)
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on March 17, 2023, 09:15:08 pm
Hello folks,

I just found out about this thread on eevblog forums about Markus' and Karl-Heinz' Testers recently.

After reading about the latest batches of LCR-TC1/TC2 containing counterfeit or clone MCUs, I tried not to head down the "Aliexpress Alley" - so I purchased a T7-Tester that is locally branded by german distributor Joy-It. I attached some pictures - as it seems, this still is "the real deal" on the inside?

This one was purchased from reichelt.de
After you posted this i decided to buy it too, since i was in need of one and they took bank transfer as payment. my research says there's a minor issue with power with the stc chip on that model that can cause a higher standby drain as well as crashes. i'm not worried so much about the power drain since it is rechargeable.
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg3598639/#msg3598639
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 17, 2023, 09:54:59 pm
The high drain during standby was a major issue because the battery is small (and getting smaller). Nevertheless, it seems that part has already been solved by several of the manufacturers, if you want (or cannot migrate from) the chinese firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Specmaster on March 18, 2023, 12:54:50 pm
I can thoroughly recommend one of these units with the case. I've had mine now for a number of years and is the same board as this uses, there are other slight variations of the eBay for sale, but I can't vouch for those, but this one has given my very good service and is certainly reasonably accurate, checking it against bigger 4 lead devices.
https://www.ebay.co.uk/itm/155087140184 (https://www.ebay.co.uk/itm/155087140184)
There is one major issue with these Transistor Testers which have their MCU in a 32-pin TQFP package (8 pins on each of the 4 sides of the package).

     These days there are 3 totally different 32-pin TQFP package MCU chips which may appear in Transistor Testers:

Atmel ATmega328P   — this is the MCU specified by the original OSHW Transistor Tester project. However its price has increased from $3 USD to $9-10 USD, so the low-cost Chinese vendors stopped using it.

Logic Green LGT8F328P — This is a Chinese MCU which costs <$1 USD. It is said to be “somewhat” similar to the original Atmel AT328P. But unfortunately several of its pins have different functionality. Therefore a Transistor Tester containing LGT8F328P cannot easily have its MCU replaced by the Atmel ATmega328P. Also the LGT8F328P has substantially different internal features, which means existing OSHW firmware won’t work without considerable modification.

Aptchip APT32F172K8T6.  — Another Chinese MCU which costs <$1 USD. It has nothing at all in common with the original Atmel ATmega328P. The pinout is totally different. Also the internal MCU architecture is totally different.

Warning: Some of these $1 USD Chinese MCU chips have been deliberately mislabeled as “Atmel ATmega328P.”

More discussions about this are found here:
   https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4613737/?topicseen#msg4613737 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4613737/?topicseen#msg4613737)
   https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/?topicseen#msg4610314 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/?topicseen#msg4610314)
   https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4600771/#msg4600771 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4600771/#msg4600771)
I was not aware of this, however, if anything other than a capacitor or resistor failed, wouldn't it be better to replace the whole unit seeing as it is such a low cost unit, rather than run the gauntlet of facing a possible problem with fake chips? 
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 18, 2023, 02:58:46 pm
I was not aware of this, however, if anything other than a capacitor or resistor failed, wouldn't it be better to replace the whole unit seeing as it is such a low cost unit, rather than run the gauntlet of facing a possible problem with fake chips?
At the present time (March 2013) I can provide two recommendations worth considering. The choice depends on whether one wants a simple little device to toss into their toolbox for quick measurements (with limited accuracy), or whether they wish to learn more of “the details” of the Transistor Tester project with the intention of improving and customizing their device into an accurate and dependable bench instrument.

1)    For those who wish to get a functional Transistor Tester which won’t need any modification I specifically recommend the “LCR-TC2 V2.3E” model. Please expect to pay $30-40 USD for it. This  model contains a genuine Atmel ATmega324 MCU chip (44-pin TQFP square package).
Example:  https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4753835/?topicseen#msg4753835 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4753835/?topicseen#msg4753835)

2) For those who wish to modify/customize/improve their Transistor Tester I recommend the “kit-form” AY-AT GM328 “color” units which come as a bare PC board and a bag of parts. These units use the Atmel ATmega328P (28-pin DIP package).
Example:   https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4681222/?topicseen#msg4681222 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4681222/?topicseen#msg4681222)

3) Avoid purchasing “LCR style” units (plastic case with rechargeable battery inside) costing <$25 USD. Nearly all of these will contain cheap (<$1 USD) Chinese MCU chips. Most will be only partially functional. The OSHW Transistor Tester firmware does not currently support any of these $1 Chinese MCU chips.

Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 18, 2023, 03:51:52 pm
I like DIP because of the ease of swapping out the chip. What would be the advantage of an ATmega324 over ATmega328 to pay a premium for a tester based on it?
1) Some of us want a Transistor Tester which comes in an attractive “toolbox-friendly” finished plastic case with a self-contained USB rechargeable battery, rather than an unenclosed PC board with a loose 9V battery dangling by its cable.

2) High-quality LCR-style units contain the ATmega324 MCU in a 44-pin TQFP package. In contrast, “cheap” LCR-style units have 32-pin MCU chips which probably aren’t the Atmel ATmega328P. However there aren’t yet any alternative “cheap” MCU chips which come in 44-pin TQFP packages. Therefore if a Transistor Tester contains a 44-pin TQFP MCU chip this indicates the MCU is likely to be an authentic Atmel ATmega324, rather than some dodgy $0.25 USD MCU with unknown architecture running poorly designed Chinese firmware which cannot be upgraded.

3) Transistor Testers with ATmega324 can be upgraded to ATmega644 to get twice as much flash (64k vs. 32k). This enables activating all of the advanced features offered by some versions of the open-source Transistor Tester software. The ATmega324 and ATmega644 have the same physical dimensions and pinout.

None of this is what I was asking. Looking to build, not buy. Need info.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 18, 2023, 04:36:13 pm
I like DIP because of the ease of swapping out the chip. What would be the advantage of an ATmega324 over ATmega328 to pay a premium for a tester based on it?
ATMega324 has more I/O ports than ATMega328 DIP. Therefore, you simply have more chanses and options for connecting peripheral sources for the tester. I don’t see any more advantages. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 18, 2023, 05:55:12 pm
None of this is what I was asking. Looking to build, not buy. Need info.

Please see https://github.com/kubi48/TransistorTester-documentation for Karl-Heinz' excellent documentation which includes schematics and a few hardware options. One benefit of an ATmega324 is that the additional pins allow you to assign things differently, making the use of hardware SPI possible (which is great for color displays). If you go for more features a 644 would be the better choice as the 328/324's flash is easily maxed out.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 18, 2023, 06:13:43 pm
I see. Thanks.

A problem with a thread as huge as this is that even when you know what you're looking for, it's not always easy to find. It would be nice to have either the first post or a separate page (or web site?) that links to the current important stuff: Where the current repository is, where the most updated documentation is, where the different modifications are described (like how to wire up a display for hardware SPI for example).

A bit unrelated, I wanted to ask if you'd ever managed to solve the problem with LC add-on where it was counting too many pulses.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on March 18, 2023, 07:01:12 pm
I know that many are unhappy with the tester that contains the APT32F172K8T6 (TC1 in my case).
But if you don't know anything about ATmega and firmware etc., it's not that bad for ~$10 including battery and case.
Despite the small battery, it has a really good endurance.
Once the problem with KAA range is solved (2K2 resistor) there is no reason to throw it away. Imo it's worth the money.

I randomly tested some components (cheap chinese stuff in a big bag). Here are the results.
Imho even the ESR values seem plausible.

Resistors:
680k -> 682k
220k -> 217k
51k -> 53k
3,3k -> 3.28k
100 -> 98.7

Capacitors:
6.8pF -> 6.2pF
470pF -> 520pF
3.3nF -> 3.5nF
220nF -> 240nF
470nF -> 504nF
1μF -> 0.974μF (ESR:4.1Ω)
2.5μF  -> 2.41μF (ESR:4.8Ω)
10μF -> 9.78 (ESR:0.98Ω)
22μF  -> 24.6μF (ESR:1.5Ω)
33μF  -> 32.1μF (ESR 0.8Ω)
47μF  -> 49μF (ESR:0.5Ω)
220μF  -> 228μF (ESR:0.2Ω)
470μF  -> 420μF (ESR:0.13Ω) (Aneng 8080 shows also 420μF).

Diodes:
1N4148 -> Uf=708mV C=2pf Ir=11na
1N4007 -> Uf=703mV C=9pf Ir=8na
FR107 -> Uf=666mV C=10pf Ir=10na

Zener:
3.6V -> 3.6V
5.1V -> 5.1V
12V -> 12.2V

Transistors:
A42:    NPN hFE=45  Ube=609mV Ic=5.9mA
BC547B: NPN hFE=344 Ube=774mV Ic=5.9mA
BC547C: NPN hFE=562 Ube=813mV Ic=5.9mA
C1815 : NPN hFE=382 Ube=773mV Ic=5.9mA
C8050:  NPN hFE=138 Ube=695mV Ic=5.8mA
C945:   NPN hFE=362 Ube=768mV Ic=5.9mA
S9013:  NPN hFE=151 Ube=675mV Ic=5.8mA
S9014:  NPN hFE=375 Ube=770mV Ic=5.9mA
S9018:  NPN hFE=71  Ube=735mV Ic=0.0mA
2N3904: NPN hFE=214 Ube=719mV Ic=5.9mA
2N2222: NPN hFE=289 Ube=717mV Ic=5.9mA
2N3904: NPN hFE=211 Ube=718mV Ic=5.9mA
2N5551: NPN hFE=154 Ube=681mV Ic=5.9mA

A93:    PNP hFE=116 Ube=729mV Ic=6.0mA
A733:   PNP hFE=385 Ube=890mV Ic=6.0mA
A1015:  PNP hFE=358 Ube=884mV Ic=6.0mA
2N5401: PNP hFE=162 Ube=761mV Ic=6.0mA
2N3906: PNP hFE=210 Ube=838mV Ic=5.9mA
S9012:  PNP hFE=184 Ube=776mV Ic=6.0mA
S9015:  PNP hFE=390 Ube=889mV Ic=6.0mA
S8550:  PNP hFE=345 Ube=868mV Ic=5.9mA

It definitely helps to put the components in the right drawer.  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Specmaster on March 18, 2023, 07:13:03 pm
I agree, those results are very similar to my findings and are certainly good enough to work with in the restoration / repair of other equipment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 18, 2023, 07:43:23 pm
A bit unrelated, I wanted to ask if you'd ever managed to solve the problem with LC add-on where it was counting too many pulses.

The m-firmware expects the base frequency of the LC meter hardware option to be within a specific range. Do you mean this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 18, 2023, 07:44:08 pm
...A problem with a thread as huge as this is that even when you know what you're looking for, it's not always easy to find. It would be nice to have either the first post or a separate page (or web site?) that links to the current important stuff: Where the current repository is, where the most updated documentation is, where the different modifications are described (like how to wire up a display for hardware SPI for example).
For those who haven't noticed, this Transistor Tester topic is by far the largest on the eevblog "Test Equipment" board: 8,323 replies, 2,957,670  views. In fact this might be the largest topic on the entire eevblog forum.

The sheer size of this topic does suggest that adding a "table of contents" or "faq" would be a useful task.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 18, 2023, 07:53:22 pm
A bit unrelated, I wanted to ask if you'd ever managed to solve the problem with LC add-on where it was counting too many pulses.

The m-firmware expects the base frequency of the LC meter hardware option to be within a specific range. Do you mean this?

Yes. I remember it counting too many pulses at one end of the range, probably above 500nF (but, of course, now I can't find where I saw that being stated  |O).
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 18, 2023, 08:01:20 pm
I know that many are unhappy with the tester that contains the APT32F172K8T6 (TC1 in my case).
But if you don't know anything about ATmega and firmware etc., it's not that bad for ~$10 including battery and case.
Despite the small battery, it has a really good endurance.
Once the problem with KAA range is solved (2K2 resistor) there is no reason to throw it away. Imo it's worth the money.
I also have one of these LCR-style units with the APT32F172K8T6. My unit is reasonably accurate when testing R, C, L, or zener diodes.

However, I have noticed that it sometimes totally fails to correctly identify transistors by type. On a related topic it tends to display wildly inaccurate hfe values for some transistors which test consistently within the expected range by several other transistor testers which I have on hand. I will review the notes I made when I observed this discrepancy and post them.

Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 19, 2023, 02:40:59 am
None of this is what I was asking. Looking to build, not buy. Need info.

I'm starting construction on a scratch-built DIY Transistor Tester "development system:"
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on March 19, 2023, 07:24:30 am
I have several ATmega644 and ATmega1284 MCU chips in 40-pin DIP packages.
Good idea. If socketed, makes for easy replacement since the inputs are unprotected (for a good reason).
Also dont forget to provide an USB data output. The firmware does provide for this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on March 19, 2023, 10:57:42 am
None of this is what I was asking. Looking to build, not buy. Need info.
I am starting construction on a DIY Transistor Tester myself:
I have several ATmega644 and ATmega1284 MCU chips in 40-pin DIP packages. Actually the mega644 is big enough in terms of flash size. Enabling all available features in the OSHW Transistor Tester software does require an MCU with more than 32k of flash.
I intend to use a larger color LCD display than what comes in the ready-made Chinese units.
I plan to build the first unit on a “perma-proto” style board.
My version will have a high-quality rotary encoder for user input.

It makes sense to build on this existing project. I have yet to find the original post in this thread about it.
https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/DevKit-644.kicad.tgz
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 19, 2023, 11:27:32 am
Yes. I remember it counting too many pulses at one end of the range, probably above 500nF (but, of course, now I can't find where I saw that being stated  |O).

Larger capacitance means lower frequency (lower limit is 10 kHz). The base frequency is around 595 kHz (L_i 82µH, C_i 1nF), the theoretical measurement range is 3.3 fF - 3.5 µF, and what you get with the example circuit in the repo is 10 fF - 33 nF (120 nF with signal clean-up). A different LC oscillator circuit might extend that range.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 19, 2023, 11:28:33 am
It makes sense to build on this existing project. I have yet to find the original post in this thread about it.
https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/DevKit-644.kicad.tgz (https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/DevKit-644.kicad.tgz)

Here's a picture: https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/msg1201483/#msg1201483 (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/msg1201483/#msg1201483)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on March 19, 2023, 11:45:34 am
I also have one of these LCR-style units with the APT32F172K8T6. My unit is reasonably accurate when testing R, C, L, or zener diodes.

However, I have noticed that it sometimes totally fails to correctly identify transistors by type. On a related topic it tends to display wildly inaccurate hfe values for some transistors which test consistently within the expected range by several other transistor testers which I have on hand.

Hi!

I've updated my list with some transistor measurements (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/8300/#msg4765046).
Do you see a problem with these numbers?
I don't have enough knowledge to judge that.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 19, 2023, 03:26:13 pm
Aldo22, Check these items from the list, if there are any in your household?
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/#msg4610314 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/#msg4610314)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on March 19, 2023, 03:47:26 pm
Aldo22, Check these items from the list, if there are any in your household?
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/#msg4610314 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/#msg4610314)
Thank you!
No, I don't have any of these.
All I have is in the list above (21 types).

I found that calibration is really important with this device.
If it is not freshly calibrated, it sometimes even recognizes a transistor as a resistor.
After the calibration, however, it recognizes it correctly.
Maybe even the battery status makes a difference (just a guess).

I am sure that the tester with the APT32F172K8T6 has weaknesses (like other devices?).
I just think it's not completely useless and not that bad for $10.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 19, 2023, 08:14:01 pm
Quote
10 fF - 33 nF
That's... a disappointingly short range. What's involved in the cleaning up of the signal? (I thought it came as a simple square wave at the output of the comparator.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 19, 2023, 09:39:03 pm
Aldo22  Check these items from the list, if there are any in your household?
I'll test these transistors and JFETs with my Transistor Testers and post a spreadsheet of my results here. I have large quantities of the parts listed below:
Quote
3.Some BJT transistors (for example,2N5089,MPSA12,MPSA13, etc.) are defined as thyristors or resistors.
4.Some JFET transistors (e.g. J112,J113,2N5457, etc.) are not defined at all or are defined as BJT.
I have 3 LCR-style units at this time: One with ATmega324, another with LGT8F328P, and another with APT32F172K8T6.
All have the Chinese firmware they came with. Eventually I'll put different FW into my ATmega324 unit (probably upgrading to ATmega644 at same time) but I haven't done that yet.
I also have 2 AY-AT style units and one GM328A (monochrome graphic LCD). All have Atmel ATmega328P MCU with original Chinese firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 19, 2023, 09:46:04 pm
That's... a disappointingly short range. What's involved in the cleaning up of the signal? (I thought it came as a simple square wave at the output of the comparator.)

The LM311 based LC oscillator circuit has a known issue with the signal starting around 30 nF (spurs at falling/rising edges). Another comparator or a 4093 will do the job. But starting around 120 nF the oscillator becomes unstable. It's no big deal as the LC oscillator is meant for measuring low value capacitance/inductance (below the normal range of the tester).
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 20, 2023, 06:05:08 pm
I like DIP because of the ease of swapping out the chip. What would be the advantage of an ATmega324 over ATmega328 to pay a premium for a tester based on it?
ATMega324 has more I/O ports than ATMega328 DIP. Therefore, you simply have more chanses and options for connecting peripheral sources for the tester. I don’t see any more advantages. :)
My thoughts about selecting MCU chips for scratch-built DIY Transistor Testers and also for upgrading/customizing "factory built" Transistor Testers:

The OSHW Transistor Tester requires the MCU to have GPIO ports which fully support 5V logic levels for both input and output.
There simply aren't many alternatives to the Atmel/Microchip AVR family.
The trend is for newer/faster/larger/cheaper MCU chips to operate only at 3.3V (although some can accept 5V logic signals as inputs on selected pins)
     To review: Since the Transistor Tester generates its test signals directly from MCU GPIO pins this means the MCU must be able to output a full 5V from its GPIO pins.

And with the OSHW Transistor Tester software gradually growing in features and size this makes it desirable to select an MCU with 64k (ATmega644) or 128k (ATmega1284) flash program memory. Fortunately I already have ATmega644 and ATmega1284 on hand in 40-pin DIP packages  I will use them for my scratch-built Transistor Tester.

ATmega324 TQFP-44 (square SMT package) has 44 pins vs. mega328P (TQFP-32) with only 32 pins
-   The additional pins are useful GPIO ports.
-   ATmega324 can be directly replaced by ATmega644. No alteration of PC board is needed.
-   So far none of the $1 USD Chinese MCU chips come in 44-pin TQFP.
-   Therefore a Transistor Tester which contains a 44-pin TQFP MCU is very likely to have a real ATmega324 (or ATmega644) MCU.
-   In contrast, there are at least 2 different $1 USD Chinese MCU which come in 32-pin TQFP packages.
-   This means Transistor Testers with 32-pin MCU chips could have any one of 3 different MCU chips (Atmel ATmega328P, Lucky Green LGT8F328P, or AptChip APT32F172K8T6.

Title: Re: $20 LCR ESR Transistor checker project
Post by: ayubando on March 20, 2023, 07:11:50 pm
About to finish an exact build like this, with an atmega 1284, protoboard and an ili9488 3.5 inch screen
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on March 21, 2023, 10:47:15 am
Aldo22, Check these items from the list, if there are any in your household?
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/#msg4610314 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4610314/#msg4610314)
Hi!
Could it be that the APT32F172K8T6 version has a problem with lower hFE values (~<50) on BJT transistors?
It also identifies some of my fishy A42 as resistors (4 of 10).
The same could be the case with your MPSA12 and MPSA13.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 21, 2023, 05:40:06 pm
Could it be that the APT32F172K8T6 version has a problem with lower hFE values (~<50) on BJT transistors?
It also identifies some of my fishy A42 as resistors (4 of 10). The same could be the case with your MPSA12 and MPSA13.
I plan to measure the emitter and/or collector currents during the test. This will likely require a small value current sensing resistor (1 to 10 ohms) and my oscilloscope. To the best of my knowledge the duration of hFE (gain) measurement is rather brief. Therefore it can't be measured with a DVM.

When I look at my Transistor Tester results I observe widely differing collector (or emitter) currents reported by the Transistor Testers with Chinese MCU/firmware compared to units with Atmel AVR MCU running OSHW firmware. The gain of a BJT depends quite a bit on the collector current it is measured with. This is especially true for power transistors. Curiously NPN transistors have considerably lower gain at low currents vs. high currents compared to PNP transistors where the hFE is relatively stable over a wide range of collector currents.

I'm getting real close to measuring a whole bunch of different BJT and JFET with several different Transistor Testers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on March 21, 2023, 08:10:05 pm
sounds like there's some kind of hardware bug with the mcu. the rp2040 for instance had an adc bug, but could be compensated for by notching out some spikes in software. link here although it's off topic.
https://www.hackster.io/news/raspberry-pi-confirms-it-is-investigating-a-flaw-in-the-raspberry-pi-pico-rp2040-adc-95c393b55dfb (https://www.hackster.io/news/raspberry-pi-confirms-it-is-investigating-a-flaw-in-the-raspberry-pi-pico-rp2040-adc-95c393b55dfb)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on March 22, 2023, 09:49:07 am
When I look at my Transistor Tester results I observe widely differing collector (or emitter) currents reported by the Transistor Testers
I only have a TC1 with the APT32F172K8T6 and a Fnirsi DSO-TC2.
The DSO-TC2 reports a range of Ic from ~2.5mA (mostly for NPN) to  ~5.5mA (mostly for PNP) afaics, while the TC1 always shows ~6 mA (see my list above).
If you have a look a these curves, this might explain the big difference in some cases, e.g. for MPSA 42.
https://www.biophysicslab.com/2021/04/27/testing_transistor_hfe/ (https://www.biophysicslab.com/2021/04/27/testing_transistor_hfe/)
In most cases, however, 6mA seems to be a reasonable (average) value.

EDIT: Not quite true. The DSO-TC2 sometimes reports Ie.

A42, C1815
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 22, 2023, 10:33:34 pm
I only have a TC1 with the APT32F172K8T6 and a Fnirsi DSO-TC2.
The DSO-TC2 reports a range of Ic from ~2.5mA (mostly for NPN) to  ~5.5mA (mostly for PNP) afaics, while the TC1 always shows ~6 mA (see my list above).
If you have a look a these curves, this might explain the big difference in some cases, e.g. for MPSA 42.
   https://www.biophysicslab.com/2021/04/27/testing_transistor_hfe/ (https://www.biophysicslab.com/2021/04/27/testing_transistor_hfe/)
In most cases, however, 6mA seems to be a reasonable (average) value. EDIT: Not quite true. The DSO-TC2 sometimes reports Ie. A42, C1815
That URL contains an excellent article about testing BJT gain. The curves shown are typical of NPN devices.

Note: My APT32F172K8T6 TC1 does this:
- Pressing "Start" button 4 times in quick succession (from off) causes my TC1 to display: FNIRSI-TC1 BOOTLOADER.
- It displays FNIRSI-TC1  for ~2 seconds just after entering self-test mode by pressing "Start" with a short between 1-2-3.

I wonder if FNIRSI makes these APT32F172K8T6  TC1 units?
(It is also possible the actual maker "borrowed" the FNIRSI name to try to make their knock-off product look more legitimate.)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on March 22, 2023, 11:18:14 pm
I wonder if FNIRSI makes these APT32F172K8T6  TC1 units?
I doubt it - I suspect the actual manufacturer "borrowed" the FNIRSI name to try to make their product look more legitimate.
Note: Pressing "Start" button 4 times in quick succession does cause my TC1 to display: FNIRSI-TC1 BOOTLOADER.
Yes, it also shows "Fnirsi-TC1" in self-test mode for me.
I'm not sure either. "Fnirsi" is not written anywhere else, neither on the case nor on the circuit board.
In any case, the DSO-TC2 has a different level of quality.
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on March 23, 2023, 11:45:31 pm
I have ordered a through hole DIY kit.  Is it worth it doing the things in this mod just for general use?  https://github.com/blurpy/transistor-tester
Title: Re: $20 LCR ESR Transistor checker project
Post by: wandows on March 24, 2023, 02:02:15 am
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1742501)


is this a full version of the LCR ESR Transistor Tester Project?
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 24, 2023, 05:00:59 am
I have ordered a through hole DIY kit.  Is it worth it doing the things in this mod just for general use?  https://github.com/blurpy/transistor-tester
That’s a very good set of recommendations. Note that it begins by explaining the importance of matching the probe resistors. Especially the three 680 ohm probe resistors. They don’t need to be precisely 680 ohms, but they need to match each other within +/- 0.5 ohms. The three 470k ohm probe resistors also need to match each other. Unfortunately the resistors which come with these kits usually aren’t matched. Replacing these six resistors with high-quality 0.1% precision resistors is a great place to start.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2023, 11:21:14 am
is this a full version of the LCR ESR Transistor Tester Project?

No, it's my 644 developement board (https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/DevKit-644.kicad.tgz) and a display board with level shifters. The dev board features the Zener check with boost converter, rotary encoder, 2.5V reference, self-adjustment cap, SRV05-4 input protection and the SamplingADC cap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on March 24, 2023, 12:14:31 pm
Hi all, sorry- tried reading the whole forum, but it will take a few months..

I have a LCR-TC2 with a Mega324PA cpu, on a T7-plus V1.1 board, 6 pin connector to 160x128 display subboard.
Originally was showing v3.1E firmware, but had a very bad(although consistent) accuracy on certain resistor values only, and very low reading on zeners below 10V(showing less than 1V). Input ports were not blown- confirmed it by measuring equal resistance of few hundred kOhm to Vcc and Gnd.

Soldered headers for main cpu, and U3(in my case), tried a few pre-compiled firmware(.hex and .eep) files without success. Best I can get is startup, quick measurement, and then almost immediate off(with v1.34m).
Is there any alternative firmware for the U3 chip? It gets recognized by STC-ISP as STC15L104W, but the only firmware I have is tc1_u4_v0.3.1.hex(which flashes without error). Or is it the main program that's not right?

If I need to compile from a source file, why are there no mega324 subfolders inside the trunk folders of both developers?
Sorry about the noob questions, but have been battling for few days.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2023, 02:13:02 pm
Is there any alternative firmware for the U3 chip? It gets recognized by STC-ISP as STC15L104W, but the only firmware I have is tc1_u4_v0.3.1.hex(which flashes without error). Or is it the main program that's not right?

Nope, the STC15 firmware from https://github.com/atar-axis/tc1-u4 (https://github.com/atar-axis/tc1-u4) should also work for your tester. Alternatively you could replace U3 with a simple two-transistor circuit (https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/TC1-Mod.pdf (https://github.com/madires/Transistortester-Warehouse/blob/master/Hardware/TC1-Mod.pdf)). And yes, the m-firmware could be configured incorrectly. In the source archive is a file called 'Clones' which lists the recommended settings for various clones, including the TC family.

If I need to compile from a source file, why are there no mega324 subfolders inside the trunk folders of both developers?

The k-firmware needs a small modification for the ATmega324 (see https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4637602/#msg4637602] (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4637602/#msg4637602) and the next few posts). And the m-firmware doesn't provide any binaries as there are too many configuration possibilities.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 24, 2023, 02:23:39 pm
The dev board features the Zener check with boost converter, rotary encoder, 2.5V reference, self-adjustment cap, SRV05-4 input protection and the SamplingADC cap.
I’ve read many posts claiming the “2.5V reference IC isn’t needed if the 5V regulator is very precise in voltage and free of drift.”

What is your current opinion about this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2023, 02:47:52 pm
Still the same, i.e. the external 2.5V voltage reference should be at least 10 times more precise than the 5V voltage regulator to make sense. The dev board has an external reference for testing purposes (in this case an LM4040).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on March 24, 2023, 06:32:16 pm
...it's my 644 developement board... features the Zener check with boost converter, rotary encoder, 2.5V reference, self-adjustment cap, SRV05-4 input protection and the SamplingADC cap.
I'm curious about the MCP1702 at the boost converter input. Any reason to use that precision regulator there instead of an AMS1117-5.0 or 78L05?

Also curious about the 'logic probe' option. Do you think about including that circuit on the dev kit schematic?

The 'SamplingADC cap relay' option is on the schematic but firmware files say 'not suppoted yet', 'not implemented yet'. Is there any developement about it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 24, 2023, 07:10:40 pm
Any 5V regulator is fine. I simply had a bunch of MCP1702s at hand. The logic probe option is a dedicated ADC pin with a voltage divider, quite easy to add. I don't think I'll add it to the dev kit to keep one ADC pin free for testing future options. The SamplingADC is currently supported only by the k-firmware, and I don't have any plans to add it to the m-firmware any time soon. Also, I don't know if Karl-Heinz already added support for the cap relay option.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 9voltbrain on March 27, 2023, 07:53:31 pm
About the LCR-T7... The rechargeable battery is making me a little paranoid, plus I think it's annoying having to keep it charged, so I'm thinking of replacing it with AAA-batteries. How hard would this be? Would I need to regulate the voltage down from 4.5 volts (3xAAA), or can it handle 4.5? The rechargeable battery is 3.7v.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on March 27, 2023, 09:40:28 pm
i saw a post saying the stc chip in the t7 is only rated for 3v max, and so using it with a 3.7v li ion is overdriving. in that case, two aa cells in series would be sufficient.when (if) mine arrives i may do as others did and use a switch in series with the battery to prevent discharge if it is an issue. aa cells are expensive, i think you would be going backwards.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 27, 2023, 10:34:35 pm
About the LCR-T7... The rechargeable battery is making me a little paranoid, plus I think it's annoying having to keep it charged, so I'm thinking of replacing it with AAA-batteries. How hard would this be? Would I need to regulate the voltage down from 4.5 volts (3xAAA), or can it handle 4.5? The rechargeable battery is 3.7v.
Title: Re: $20 LCR ESR Transistor checker project
Post by: thm_w on March 27, 2023, 10:55:21 pm
Can't believe there is still no STM32 or other high end port of this tester. Some regular alix models are selling for $30.
Usually Chinese products are very quick to swap out the micro to a completely different model. But maybe the atmega clones are so cheap there is no incentive.

Anyone here working on it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: 9voltbrain on March 27, 2023, 11:40:56 pm
About the LCR-T7... The rechargeable battery is making me a little paranoid, plus I think it's annoying having to keep it charged, so I'm thinking of replacing it with AAA-batteries. How hard would this be? Would I need to regulate the voltage down from 4.5 volts (3xAAA), or can it handle 4.5? The rechargeable battery is 3.7v.
To feed the ctester with something less than 5V, and variable (as batteries goes flat) would give you all sort of troubles. For starter remember this is comparing voltages samples against references. So I would rather find a bigger Li-Ion battery and/or modify the circuit as I stated above. But if you really want to use AAA size, I would analize whether the existing charger/boost converter could handle that scenario[/li][/list]

The battery that comes with it is already lower than 5V (3.7), so how would this be more of an issue with AAA? When the battery voltage drops too low for it to regulate to its desired operating voltage, it's going to tell me to "charge", then I'll just change the batteries. Am I missing something?
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on March 27, 2023, 11:48:23 pm
Can't believe there is still no STM32 or other high end port of this tester. Some regular alix models are selling for $30.
Usually Chinese products are very quick to swap out the micro to a completely different model. But maybe the atmega clones are so cheap there is no incentive.
Anyone here working on it?
In the existing Transistor Tester hardware architecture several MCU I/O pins are directly connected to the 3 probe terminals (or connected through the 680 ohm and 470k ohm probe resistors). This requires the MCU to directly support 5V I/O for digital outputs and inputs. Also the on-chip A/D converter needs to accept 0-5V. If the test voltages were limited to 3V it would become impossible to test most transistors, JFETs, and MOSFETs.

A substantial amount of additional analog driver and level-shifting hardware will be necessary to make the Transistor Tester concept functional with a 3V MCU. It will no longer be a “simple” circuit design where the MCU itself does most of the work.

With that said, if  an analog driver section was to be developed it would be feasible to support testing with voltages >5V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: thm_w on March 28, 2023, 01:30:27 am
Can't believe there is still no STM32 or other high end port of this tester. Some regular alix models are selling for $30.
Usually Chinese products are very quick to swap out the micro to a completely different model. But maybe the atmega clones are so cheap there is no incentive.
Anyone here working on it?
In the existing Transistor Tester hardware architecture several MCU I/O pins are directly connected to the 3 probe terminals (or connected through the 680 ohm and 470k ohm probe resistors). This requires the MCU to directly support 5V I/O for digital outputs and inputs. Also the on-chip A/D converter needs to accept 0-5V. If the test voltages were limited to 3V it would become impossible to test most transistors, JFETs, and MOSFETs.

A substantial amount of additional analog driver and level-shifting hardware will be necessary to make the Transistor Tester concept functional with a 3V MCU. It will no longer be a “simple” circuit design where the MCU itself does most of the work.

With that said, if  an analog driver section was to be developed it would be feasible to support testing with voltages >5V.

Yeah I did see a bit about that earlier but your explanation is much clearer, thank you.
It would be cool to have more than 5V available on all of the testing pins, on a higher end version. IMO.

There is also say the ATSAMC20G18A, instead of STM32, which can do 5V.

Looks like the $100 Peak DCA55 only supports 5V as well.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on March 28, 2023, 08:00:37 am
there are 8051 mcus widely available. they tend to be more ram limited than the current atmega (300 bytes) due to  their age, but they're much cheaper. some have 64k of flash. If you wanted to avoid the scarcity issue it would be a good way to go.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 28, 2023, 08:12:13 am
Can't believe there is still no STM32 or other high end port of this tester. Some regular alix models are selling for $30.
Anyone here working on it?
There is such a port and it is called DSO-TC2. And now, Chinese friends have launched an updated version of DSO-TC3 on the market, in which they added a signal generator and also taught how to measure the ESR of capacitors.
It is interesting to look at the circuitry of this clone and find out how it is possible to match the power supply of the STM with checking parts with a higher voltage?  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 28, 2023, 11:25:45 am
The battery that comes with it is already lower than 5V (3.7), so how would this be more of an issue with AAA? When the battery voltage drops too low for it to regulate to its desired operating voltage, it's going to tell me to "charge", then I'll just change the batteries. Am I missing something?
Similar to a power bank, your ctester comes with a 3.7V Li-Ion charger and boost converter to 5V, designed to operate within 4.2V to 3.2V or so. A new set of 3x AAA can be between 4.8V full or 2.7V flat.

As I said, if you connect the alkaline batteries directly to the main MCU you will have a lot of trouble. And if you connect it to where the actual battery is, you would have to check whether that IC supports 5V Vbatt (and put a tape over the microUSB input), and how it would be behave under that scenario.

Let's say it does: If your ctester shut off at 3.5V, you would be replacing alkaline batteries with around 45% of charge remaning.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 28, 2023, 01:50:13 pm
About the LCR-T7... The rechargeable battery is making me a little paranoid, plus I think it's annoying having to keep it charged, so I'm thinking of replacing it with AAA-batteries. How hard would this be? Would I need to regulate the voltage down from 4.5 volts (3xAAA), or can it handle 4.5? The rechargeable battery is 3.7v.

You could add a simple switch to prevent discharging by the control MCU. When going for the AAA batteries check if the Li-Ion charger chip will be happy with the higher voltage or needs to be removed. The second thing to check is the control MCU. The STC15L104W is rated for 2.4 to 3.6V (STC15F104W 3.8 - 5.5V).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Cliff Matthews on March 29, 2023, 11:47:47 am
Can't believe there is still no STM32 or other high end port of this tester. Some regular alix models are selling for $30.
Anyone here working on it?
There is such a port and it is called DSO-TC2. And now, Chinese friends have launched an updated version of DSO-TC3 on the market, in which they added a signal generator and also taught how to measure the ESR of capacitors.
It is interesting to look at the circuitry of this clone and find out how it is possible to match the power supply of the STM with checking parts with a higher voltage?  :D
TC3 first looks here I think
https://www.youtube.com/watch?v=JpISM7g9Ff4 (https://www.youtube.com/watch?v=JpISM7g9Ff4)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on March 29, 2023, 03:28:35 pm
Thanks for the answers, Madires.

Any 5V regulator is fine. I simply had a bunch of MCP1702s at hand.
Just noticed the 'Extented circuit with ATmega644' in Karl-Heinz's pdf document also has MCP1702 in the same place. :)

The logic probe option is a dedicated ADC pin with a voltage divider, quite easy to add. I don't think I'll add it to the dev kit to keep one ADC pin free for testing future options.
Yes, the voltage divider is easy to add. I just thought seeing the options on the schematic would be better than discovering them inside the firmware files.

The SamplingADC is currently supported only by the k-firmware, and I don't have any plans to add it to the m-firmware any time soon. Also, I don't know if Karl-Heinz already added support for the cap relay option.
As far as I see there is no mention of cap relay in the k-fw makefile and config files.

I also noticed the 'extented circuit' schematic uses a darlington BJT for 'power management', your dev-kit schematic has a standard BJT there. I imagine it's just preference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on March 29, 2023, 04:04:49 pm
i received my joyit lcr-t7 from reichelt.de today. i tried the self test with the three terminals shorted but it pauses indefinitely at 26% unless the short is removed. the pcb is the same as the previous user posted, with the dip mcu.
I guess if i want to calibrate it i'd have to change a resistor somewhere to get the self test to run. i dont plan to do so because smt is painful for me, and if i put a through hole part on it would surely tear the traces.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 29, 2023, 05:04:35 pm
Yes, the voltage divider is easy to add. I just thought seeing the options on the schematic would be better than discovering them inside the firmware files.

True! I'll add a simple diagram to the README file.

I also noticed the 'extented circuit' schematic uses a darlington BJT for 'power management', your dev-kit schematic has a standard BJT there. I imagine it's just preference.

Yep, any PNP with a sufficient high hFE and current rating is fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 29, 2023, 05:15:20 pm
i received my joyit lcr-t7 from reichelt.de today. i tried the self test with the three terminals shorted but it pauses indefinitely at 26% unless the short is removed.

Around 22% the tester will ask to remove the short (small text below the progress bar). It's part of the normal self-adjustment.

I guess if i want to calibrate it i'd have to change a resistor somewhere to get the self test to run. i dont plan to do so because smt is painful for me, and if i put a through hole part on it would surely tear the traces.

If the tester has an ATmega you can flash the original OSHW firmware with much more features.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mcgyvr81 on March 29, 2023, 05:20:16 pm
i received my joyit lcr-t7 from reichelt.de today. i tried the self test with the three terminals shorted but it pauses indefinitely at 26% unless the short is removed. the pcb is the same as the previous user posted, with the dip mcu.
I guess if i want to calibrate it i'd have to change a resistor somewhere to get the self test to run. i dont plan to do so because smt is painful for me, and if i put a through hole part on it would surely tear the traces.

No, this is standard behaviour of this tester. It requires 1,2,3 to be shorted upon startup to enter self-test mode, then have the short removed when requested to complete the test. This happens to be at 26% on my unit as well - it flashes the request to remove the short on the bottom of the screen when it's waiting for it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 29, 2023, 05:26:15 pm
And now, Chinese friends have launched an updated version of DSO-TC3 on the market, in which they added a signal generator and also taught how to measure the ESR of capacitors.
This is how the new DSO-TC3 measures the ESR of capacitors. While the Chinese friends have a lot of work to achieve similar results on the classic AVR. In the meantime, the ESR of this device shows the weather on Mars and not the actual equivalent resistance values. :-DD
However, like other similar testers that are not built on the original ATMEL.
In the photo, for comparison, the measurement of the same capacitor with the mod m-firmware 1.48m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on March 30, 2023, 08:02:34 am
This is how the new DSO-TC3 measures the ESR of capacitors.
The photo does not show which capacitor is being measured. Such readings are typical for ceramic capacitors. Here are the measurements on the firmwares of both authors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 30, 2023, 08:12:49 am
The photo does not show which capacitor is being measured.
The photo shows the measurement of an electrolytic capacitor 4.7uF(not ceramic). Is it really not clear that such a electrolytic capacitor of any company cannot have ESR = 0.11Ohm ?
Here are some more comparison photos for example. Transistor KП103 DSO-TC3 defines as a resistor. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on March 30, 2023, 01:42:13 pm
The photo shows the measurement of an electrolytic capacitor 4.7uF(not ceramic). Is it really not clear that such a capacitor of any company cannot have ESR = 0.11Ohm ?
I have some 10uF/16V Sanyo Os-con polymer electrolytics that measure ESR=0.11 Ohm
https://en.wikipedia.org/wiki/Polymer_capacitor
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 30, 2023, 01:45:02 pm
Fuzzy Star,and the photographs that I provided do show polymer capacitors? :) Or does DSO-TC3 define them as polymer? :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on March 30, 2023, 03:39:05 pm
Fuzzy Star,and the photographs that I provided do show polymer capacitors? :) Or does DSO-TC3 define them as polymer? :-DD
"electrolytic capacitor 4.7uF(not ceramic)... such a capacitor of any company"
Polymer capacitors are electrolytics, too and they don't look different. We can't be sure from your photo what type of electrolytic is it.

does DSO-TC3 define them as polymer? :-DD
Do these testers can detect and display capacitor type?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 30, 2023, 04:01:24 pm
Polymer capacitors are electrolytics, too and they don't look different. We can't be sure from your photo what type of electrolytic is it.
I assure you that the photo measured is an ordinary electrolytic capacitor, not a polymer one. If you can't tell the difference between an ordinary electrolyte and a polymer one, I'm sorry.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on March 31, 2023, 11:25:27 am
Ok, I bricked it, took a week 8)
Maybe this will help someone avoid doing the same:
The Windows installation of WinAVR for some reason installs an empty folder for Programmers Notepad. So, used WinAVR Portable. Didn't [apparently] need to install the extra toolchain, but had to change the msys-1.0 file inside C:\WinAVR_Portable_V14_1\WinAVR-20100110\utils\bin to get everything to compile without errors.
The 1.44m firmware compiled fine with minimal set of features, the 1.48m was giving an error, so when I compared the 1.44 and 1.48 I saw both #define SPI_BITBANG, and #define SPI_HARDWARE were commented off. Enabling #define SPI_BITBANG made it compile without error..

That's when I decided to try SPI_HARDWARE, and also manually changed the low fuse from 0xff to 0xf7 using Avrdudess(I saw inside the Makefile: LFUSE_CRYSTAL = -U lfuse:w:0xf7:m, since I have a mega324pa, running 16 MHz external crystal)... //famous last words...

Whichever of the above did the trick, I cannot program anything on the cpu anymore, everytime avrdude "Detect" shows different device signature, and any attempt to change fuses or firmware gives an error. And of course the screen stays blank.
Any suggestions regarding resetting the fuses would be welcome :-DD, but it looks like- apart from cpu swap(which would be practically impossible, since i have no hot air station/experience), it's only good for the dust bin.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 31, 2023, 01:44:35 pm
You can debrick an ATmega324 by high-voltage (parallel) programming or maybe JTAG. Only a few ATmega programmers support the high-voltage mode, but some (many?) universal programmers do.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ekoloski on March 31, 2023, 05:21:46 pm
Fuse bits are dangerous...

It looks like that fuse config set the AVR to expect a low power crystal oscillator. If there's a crystal on there that just isn't being driven right, maybe you can rescue it by setting a slower bitrate and trying to program the fuse? With avrdude it's the -B option (substitute in your parameters for the programmer you're using, and experiment with the -B flag which is the bitclock period in uS): avrdude -p m324 -B20 ... -U lfuse:w:0xff:m

Otherwise as the previous poster mentioned, parallel programming is the way to recover it. The catch is that you'd need to remove the chip from the board first and you've stated that's a no go. Maybe there's someone local who can help out with the desoldering if necessary?

A number of programmers out there support hvpp. I personally use an older AVR Dragon, but some people even make their own programmers out of another AVR. If you are able to get it removed it would be something similar to:

avrdude -p m324 -P usb -c dragon_pp -U lfuse:w:0xff:m



Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on March 31, 2023, 06:59:59 pm
Thanks for the replies! Why is it necessary to remove the chip for parallel programming? If I ensure all peripherals are disconnected, can't I do it in-circuit? I've already written it off, so wouldn't mind trying anything, if it will help others.
Sorry for wasting the time of one of the project creators :-[!
Title: Re: $20 LCR ESR Transistor checker project
Post by: ekoloski on March 31, 2023, 07:14:30 pm
I'd remove the chip out of caution, since I don't know what the schematic for this board looks like. HVPP uses 12 volts on the Reset line, if anything else on the board is connected to it and is not tolerant of 12V it could be damaged.

Beyond that, anything else connected to the pins could load it down and interfere with the programming. And lets not forget that there are a LOT of pins to connect (21 of them!) for parallel programming.

If there really isn't anything else on those pins that could get damaged or interfere, then you're right. The chip could be programmed in-place.

For reference, below is a snapshot from page 368 of the datasheet (this is a Mega324, right?) which shows the pins for parallel programming. Note that in addition to each named line all of PB is connected for data.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on April 01, 2023, 02:44:47 pm
Any suggestions regarding resetting the fuses would be welcome
Another method for recovering a bricked AVR is using an external clock/oscillator. I did a quick search and found these:

https://www.eevblog.com/forum/beginners/bricked-atmega-1284-with-avrdude (https://www.eevblog.com/forum/beginners/bricked-atmega-1284-with-avrdude)!-can-it-be-saved/
https://www.avrfreaks.net/s/topic/a5C3l000000UMBiEAO/t099084 (https://www.avrfreaks.net/s/topic/a5C3l000000UMBiEAO/t099084)
https://www.avrfreaks.net/s/topic/a5C3l000000UboeEAC/t159156 (https://www.avrfreaks.net/s/topic/a5C3l000000UboeEAC/t159156)
https://classbproject.com/fixes-and-hacks/recovering-a-bricked-avr/ (https://classbproject.com/fixes-and-hacks/recovering-a-bricked-avr/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on April 03, 2023, 08:51:36 am
Hello everybody.
It was necessary to measure the capacitance of the coaxial wire (about 1m), I plan to make a probe for the oscilloscope, but I noticed something odd.
Compared with the device RM219.
Those. ordinary capacitances measure +/- the same way (taking into account the error), in the photo just for example the capacitance is 1 microfarad (yellow) and 10nF (green) ...
But that's it when measuring a piece of cable - the readings differ twice!??? I measured other pieces 50cm ... and 1.5m ... also a huge discrepancy ...
Moreover, measurements of other components are normal ... if there are discrepancies, then they fit perfectly into the errors (and my needs).
Usually I measure something with either a device or a tester and there have never been any problems ... but here an incomprehensible situation arose with the measurement of the cable .. Maybe someone came across? Is it in different ways or features of measuring instruments?
I want to know what to believe anyway...
Or maybe someone will also conduct a similar test (wire range from 0.75 - 1.2m coaxial), will you have discrepancies?

It’s just that later I’ll calculate the compensation capacity and I don’t know what evidence to build on ...
The cable is marked RG58A / U (but I doubt that this is the original ...)

Tester G328A(BGR), firmware costs 1.13k (from Yuriy_K from page 277)
In principle, I can try to flash 1.44m (Thanks to indman,
  for help in compiling in due time ...), only the USBASP-programmer threw it somewhere, but I can search(But I don't think it's a firmware issue...) ...

p.s. According to the videos on the network, who made such probes, the capacitance is within 30-45nF for people ... i.e. the readings of the tester in this case are greatly overestimated (I don’t understand the reason), but the readings of the device 219 are, as it were, normal ...
This is probably some kind of feature of measurements by a tester of coaxial cables?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 03, 2023, 12:06:16 pm
The Transistor Tester doesn't use an AC signal to measure capacitance. Instead it charges the DUT to a specific voltage, counts the time, and calculates the capacitance from that. It measures the DC capacitance. For a transmission line, e.g. a coax cable, a proper LCR meter with an AC signal is recommended.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on April 03, 2023, 12:22:19 pm
This is probably some kind of feature of measurements by a tester of coaxial cables?
The indications should not depend on the methods of measurement. Here are examples of measurements on different instruments...

Attention! Added,  for the TTester on both firmware, there is a dependence of the readings on the connection of the leads to the measuring terminals.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on April 03, 2023, 12:28:17 pm
I measured other pieces 50cm ... and 1.5m ... also a huge discrepancy ...
The capacitance of a coax cable is function of its length (think about the capacitance of two conductors in parallel of variable lenght separated a constant distance by a dielectric, the more the length, the more charge can be stored). In fact, if you look at the manufacturer datasheet it will tell you the typical pF/m or nF/m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on April 03, 2023, 12:52:19 pm
The Transistor Tester doesn't use an AC signal to measure capacitance. Instead it charges the DUT to a specific voltage, counts the time, and calculates the capacitance from that. It measures the DC capacitance. For a transmission line, e.g. a coax cable, a proper LCR meter with an AC signal is recommended.

Yes, that's understandable. Unfortunately, I do not have such devices yet. I thought to measure, not perfectly accurately, but at least to decide on further calculations ...
But such a nuance turned out ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on April 03, 2023, 01:01:06 pm
The capacitance of a coax cable is function of its length....

What depends on the length, I know that.
According to the datasheet, the manufacturer claims 85pf per meter.
When I measure a long piece and a short ratio with a tester, this is how it turns out.
Also, if I measure with a multimeter, the length ratio is the same (+/- error) ...
But Yuri wrote that the readings should be the same, but for some reason I have different ones .. moreover, they simply measure the capacitors EQUALLY ... and resistors, etc.
But it was with the cable that such a nuance arose ...
I myself wonder what my problems are ... is it a multimeter? those. According to Yuri's screenshots, his tester readings approximately coincide with mine (70-80pF)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on April 03, 2023, 01:05:13 pm
The indications should not depend on the methods of measurement. Here are examples of measurements on different instruments...

Here you have "ideal" ... The tester calibrated ... Everything shows correctly ...
It happens that you need to believe his testimony (they are closer to the datasheet) .. but the multimeter turns out to be a failure for me ...
But why exactly when measuring the cable ??? This is incomprehensible to me ... after all, all other measurements for them practically coincide ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 03, 2023, 01:29:04 pm
Any suggestions regarding resetting the fuses would be welcome
Another method for recovering a bricked AVR is using an external clock/oscillator. I did a quick search and found these:

https://www.eevblog.com/forum/beginners/bricked-atmega-1284-with-avrdude (https://www.eevblog.com/forum/beginners/bricked-atmega-1284-with-avrdude)!-can-it-be-saved/
https://www.avrfreaks.net/s/topic/a5C3l000000UMBiEAO/t099084 (https://www.avrfreaks.net/s/topic/a5C3l000000UMBiEAO/t099084)
https://www.avrfreaks.net/s/topic/a5C3l000000UboeEAC/t159156 (https://www.avrfreaks.net/s/topic/a5C3l000000UboeEAC/t159156)
https://classbproject.com/fixes-and-hacks/recovering-a-bricked-avr/ (https://classbproject.com/fixes-and-hacks/recovering-a-bricked-avr/)

Connected it to an external 1 Mhz source(arduino), the mega324PA even has 125.0 kHz coming out of its PB1 pin. Running avrdudess with -b 1200 -B 56 (16 kHz SCK). Still unable to read signature, or change fuses.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hojnikb on April 03, 2023, 01:42:24 pm
  • We already had a short discussion about DurandA approach. You can go back to the posts of July 23, 2022 of this thread
  • Unless the vendor shows an internal photo (and even in that case we cannot be 100% certain), you cannot know for sure what you're going to get untill you have it in your hands. For instance, last July I bought one T1 and one T7 from Amazon, for $20+ each, from different sellers. One was the real ATmega, the other was a 32pin clone

Guess i'll have to roll the dice and see what i get. It's cheap though, so it won't matter that much.

Just got mine after 3 weeks. It has an unmarked microcontroller. By the looks of it, it seems like a 32pin deal
(https://i.imgur.com/g2F4jse.jpg)
(https://i.imgur.com/PfbNBFK.jpg)

Is there a way to know which of the clones this is ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on April 03, 2023, 01:55:33 pm
Yes, that's understandable. Unfortunately, I do not have such devices yet. I thought to measure, not perfectly accurately, but at least to decide on further calculations ...

... the ComponentTester is better than you think, correct calibration is important ...

... I carried out the measurement with different devices and documented the results in photos.

Greeting Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on April 03, 2023, 03:15:43 pm
This is probably some kind of feature of measurements by a tester of coaxial cables?
Your photo says: "Measurements of just capacitances are more or less the same ... but when measuring a cable such a spread"
The capacitances you use to compare are 1uF and 10nF. But the capacitance of the cable you're trying to measure is less than 100pF. It's such a low value to say 'spread'. Results are 40pF and 70pF, it's only 30pF difference. With such a low value, your probe capacitances and the connection methods affect the results.
How many pF the Tester shows when there is nothing connected to the probes? (keep the probes connected to the ZIF socket)

Use a 50-100pF capacitor to compare your DMM and Tester. Probably you will see a similar 'spread'.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on April 03, 2023, 03:38:08 pm
... the ComponentTester is better than you think, correct calibration is important ...
... I carried out the measurement with different devices and documented the results in photos.

Of course, the tester is an excellent device. Calibrated, I think, is also correct (I have been using it for a relatively long time and figured it out a little) ...
Here you are in the photo, I also look at the instrument readings more or less the same ...
So I have problems with the multimeter ... because. my readings are 70nF closer to those measured by Yuriy_K and you...
___________________
p.s.  I just measured a piece of double-sided textolite and ....
in general I have a COMPLETE misunderstanding ((((
The readings are almost the same (I leaned the contacts several times) +/- a few units of difference ..
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on April 03, 2023, 04:13:00 pm
....
in general I have a COMPLETE misunderstanding
Don't you understand that it is impossible to compare the readings of devices with autonomous power and kicking from a mains power supply?
The sensitivity of the TTester is so high that it reacts to the close presence of hands, like an antenna to influence network interference.
In all my examples, there is no mains power and there are no hand pickups.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on April 03, 2023, 05:14:01 pm
...With such a low value, your probe capacitances and the connection methods affect the results.
How many pF the Tester shows when there is nothing connected to the probes? (keep the probes connected to the ZIF socket)

Use a 50-100pF capacitor to compare your DMM and Tester. Probably you will see a similar 'spread'.

1. The tester shows 0.05pF-0.1pF
2. measured 15nF almost the same (I think the error is normal) ..
3. I connected the cable to the ZIF - 69-75pF, which is almost similar to the measurements from others ... i.e. tester can be trusted...
then the problem is in the multimeter ... it probably can't cope ...
Okay, I'll focus on the tester.
Thanks to EVERYONE who helped :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 03, 2023, 05:28:18 pm
tester can be trusted...
then the problem is in the multimeter ... it probably can't cope ...
The problem is in your multimeter, which has a large error when measuring the picofarad range. Try to measure the usual capacitance of 10-20pF on this multimeter and you will immediately see the difference in the readings.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on April 03, 2023, 05:52:20 pm
....Don't you understand that it is impossible to compare the readings of devices with autonomous power and kicking from a mains power supply?
The sensitivity of the TTester is so high that it reacts to the close presence of hands, like an antenna to influence network interference.
In all my examples, there is no mains power and there are no hand pickups.

So I have both a multimeter and a tester powered by batteries ...
I take into account the influence of the hands, and I understand that they can influence ... but the fact is that when everything is connected and the hands are removed - for some reason, when measuring the cable, this is what happens ...
In all other measurements, the tester and multimeter are almost the same ...
Here ONLY this coaxial cable froze and confused ... it seems to me that even with "noise", there should not be such a large spread ...
But for now, I decided to trust the testimony of the tester (of course, having correctly connected it to the ZIF panel and removed my hands away)
---------------------------------
Tell me more please. On page 317 Your options for BGR display - ST7735_BGR_en.zip is this the final option for G328A(BGR)? Those. Can I reflash this k-version over 1.13 color?
-------------------------------------
I have the m-firmware version 1.44 extreme .... still available :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 03, 2023, 11:00:26 pm
Just got mine after 3 weeks. It has an unmarked microcontroller. By the looks of it, it seems like a 32pin deal. Is there a way to know which of the clones this is ?
That is a Logic Green LGT8F328P MCU. It is said to be "almost" compatible with the Atmel ATmega328P. However the pinout is slightly different. As of yet there really isn't any fully tested OSHW Transistor Tester software for it, although this person is working on it:
     https://github.com/DurandA/transistor-tester-lgt328p (https://github.com/DurandA/transistor-tester-lgt328p)

I have also read discussions stating "it may be possible to rework the PC board for Atmel ATmega328P."
Title: Re: $20 LCR ESR Transistor checker project
Post by: hojnikb on April 04, 2023, 06:18:37 am
Just got mine after 3 weeks. It has an unmarked microcontroller. By the looks of it, it seems like a 32pin deal. Is there a way to know which of the clones this is ?
That is a Logic Green LGT8F328P MCU. It is said to be "almost" compatible with the Atmel ATmega328P. However the pinout is slightly different. As of yet there really isn't any fully tested OSHW Transistor Tester software for it, although this person is working on it:
     https://github.com/DurandA/transistor-tester-lgt328p (https://github.com/DurandA/transistor-tester-lgt328p)

I have also read discussions stating "it may be possible to rework the PC board for Atmel ATmega328P."

cool. Did anyone try this modified firmware... Does it actually work?
How does one go about flashing these things.... likely not serial, like arduinos?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on April 04, 2023, 04:52:58 pm
We could review/update  some discussion of last year about the several MCU clones populating the market, and DurandA initiative (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4315945/?PHPSESSID=10v69mav0slsoudpp107lg250c#msg4315945). If we re-read the discussion around those days, maybe there is something worthy to add now.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 04, 2023, 10:34:04 pm
cool. Did anyone try this modified firmware... Does it actually work?
How does one go about flashing these things.... likely not serial, like arduinos?
I don’t know very much about the DurandA project on GitHub. It hasn’t been updated in 2 years. Perhaps the author went on to other projects before finishing it? There seem to quite a few unfinished projects on GitHub.

Programming LGT8F328 chips is totally different than Atmel AVR.
The AVR programming interface is known as “ISP” and uses a 6-pin cable and a programming device.
Arduino boards have a “bootloader” which works through a TTL level or USB serial port.
But to get the bootloader onto an AVR initially requires the ISP programmer.
LGT8F328 uses a totally different programming device than AVR.

Note: Transistor Testers don’t usually have a bootloader. There’s not enough flash in 32k devices like ATmega328P or ATmega324 for them to have a bootloader and still have enough room for the Transistor Tester firmware.

Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 05, 2023, 01:24:57 am
My LCR testers turned up today.

While the chip says Atmel 328P and it did come from what should have been a reputable seller (fnirsi)  There is no crystal on the board, so I am going hmm.



Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2023, 07:17:54 am
.RC.,you got a fake from FNIRSI! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 05, 2023, 07:58:03 am
Well a fake there.

Then I try to use the second one I bought and it is DOA.

Not even the screen lights up when I connected a battery and tried to test a resistor.

Just not my day.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 05, 2023, 08:06:12 am
Not even the screen lights up when I connected a battery and tried to test a resistor.
In this option, a lot depends on how thoroughly and carefully you assembled the constructor.
Before soldering parts, it is highly desirable to check their compliance with the diagram and item number.
Very rarely, but there have been cases that the ATMEGA328 was empty. Then you need a simple programmer to determine this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 05, 2023, 01:02:44 pm
Then I try to use the second one I bought and it is DOA. Not even the screen lights up when I connected a battery and tried to test a resistor. Just not my day.
Two months ago I purchased a Transistor Tester in  “kit form” identical to the unit in your photo. I thought it was easy to assemble, but then I’m a professional EE with many years of experience.

Before starting the build I took several photos of the bare PC board since it has the labels showing where each component part is supposed to go. Then I measured the resistors with ohmmeter and put them into groups of same resistance before soldering to PC board. These resistors are small and the color bands can be difficult to read.

After assembly the LCD would turn on and display the expected screens. It was almost functional. However it was unable to enter the “self test”  mode. Then I discovered that one of the 680 ohm “probe” resistors was slightly out of spec. Details are in my previous post:

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4726172/?topicseen#msg4726172 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4726172/?topicseen#msg4726172)

I strongly recommend downloading the full Transistor Tester manual and then printing the schematic and selected pages to use while troubleshooting. I will endeavor to post a brief checklist to assist with getting these “kit form” Transistor Testers into working condition.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on April 05, 2023, 05:33:23 pm
Then I try to use the second one I bought and it is DOA.

Not even the screen lights up when I connected a battery and tried to test a resistor.

Just not my day.
Well duh, you have to solder the components to the PCB first!
Sorry, I'll find the door and let myself out :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on April 05, 2023, 08:09:36 pm
Well a fake there.

Then I try to use the second one I bought and it is DOA.

Not even the screen lights up when I connected a battery and tried to test a resistor.

Just not my day.

Worth looking at this video for troubleshooting:-
https://www.youtube.com/watch?v=h9_XkkmFfAk (https://www.youtube.com/watch?v=h9_XkkmFfAk)  #108 Building and testing an eBay Transistor Tester kit
Also feel free to post some closeup photos of the assembled board in case we can spot something.
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 05, 2023, 08:52:56 pm

Well duh, you have to solder the components to the PCB first!
Sorry, I'll find the door and let myself out :-DD

Oh, damn, I thought I must have done something wrong.   :-DD

There is another job to do.

Actually I was going to get some high precision components for the kit before I built it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vk3em on April 06, 2023, 12:23:25 am
I ordered a LCR-TC2 from SeeSensor on AliExpress which arrived today.
https://www.aliexpress.com/item/1005004717377243.html (https://www.aliexpress.com/item/1005004717377243.html)

PCB is marked T7 Plus v2.0 - mcu has no markings, 8 pins per side.

Note: This seller was previously known to ship Atmel based LCR testers (at least in Jan 2023) but now in April 2023 they have moved to the alternative.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1754720)



Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 06, 2023, 04:53:55 am
I ordered a LCR-TC2 from SeeSensor on AliExpress which arrived today.
     https://www.aliexpress.com/item/1005004717377243.html (https://www.aliexpress.com/item/1005004717377243.html)
PCB is marked T7 Plus v2.0 - mcu has no markings, 8 pins per side.
Note: This seller was previously known to ship Atmel based LCR testers (at least in Jan 2023) but now in April 2023 they have moved to the alternative
That is a Logic Green LGT8F328P MCU. It is said to be "almost" compatible with the Atmel ATmega328P. However the pinout is slightly different. As of yet there really isn't any fully tested OSHW Transistor Tester software for it, although this person is working on it:
     https://github.com/DurandA/transistor-tester-lgt328p (https://github.com/DurandA/transistor-tester-lgt328p)
I have also read discussions stating "it may be possible to rework the PC board for Atmel ATmega328P."
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 06, 2023, 04:57:16 am
...Then I try to use the second one I bought and it is DOA.
Not even the screen lights up when I connected a battery and tried to test a resistor.
Just not my day.
After looking at your photo very closely I think I understand the problem. 8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 06, 2023, 11:39:33 am
After looking at your photo very closely I think I understand the problem. 8)

Yes, there is no crystal there either, or so I found out when I was going through the components.

So I visited Ms Mouser and ordered all the parts to make it as per the proper original specs.  I actually ordered twice the number (plus some other stuff I needed) as then I got free freight, as otherwise the freight was more then the component costs. Only thing I could not get was a spare dip ATMega328 as they were out of stock.

I will probably blow this unit up down the track doing something silly.   Probably worth getting another kit anyway as who knows how long these genuine Atmel kits will be around for.  It seems the prebuilt SMD units are pretty much non Atmel now, unless you are lucky. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: vk3em on April 06, 2023, 10:57:58 pm
Quote
Probably worth getting another kit anyway as who knows how long these genuine Atmel kits will be around for.

Where can you buy it from?

Luke
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 06, 2023, 11:30:53 pm
Yes, there is no crystal there either, or so I found out when I was going through the components.
The standard factory crystal is 8MHz. That's what my "kit form" unit came with. Only part "missing" from my unit was a 10k resistor which I had dropped on the floor (I did manage to find it).
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 07, 2023, 12:34:53 am


Where can you buy it from?

Luke

I generally buy from Aliexpress now.   Seems to be far cheaper then ebay for me.

I searched with this term GM328 LCR tester  -->> https://www.aliexpress.com/w/wholesale-gm328-lcr-tester.html (https://www.aliexpress.com/w/wholesale-gm328-lcr-tester.html)

I did some searching and found one seller selling a kit for a far lower price then everyone else.   Then I noticed the three SMD components on the PCB were missing in the photo -->> https://www.aliexpress.com/item/32706710335.html (https://www.aliexpress.com/item/32706710335.html)

I also found a version that looked to be a cut down version. 

So I went for a version were multiple sellers were around a similar price.  Like -->>https://www.aliexpress.com/item/1005003127524856.html (https://www.aliexpress.com/item/1005003127524856.html)

Title: Re: $20 LCR ESR Transistor checker project
Post by: hoangtran on April 07, 2023, 04:59:11 am
I ordered a LCR-TC2 from SeeSensor on AliExpress which arrived today.
https://www.aliexpress.com/item/1005004717377243.html (https://www.aliexpress.com/item/1005004717377243.html)

PCB is marked T7 Plus v2.0 - mcu has no markings, 8 pins per side.

Note: This seller was previously known to ship Atmel based LCR testers (at least in Jan 2023) but now in April 2023 they have moved to the alternative.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1754720)

I have the same item like this. Mod to Atmega328 with 1.48m firmware. Here is the result:
Original firmware:
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1755716)
M328 with 1.48m firmware
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1755722)
Measuring with DE5000
(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1755728)


Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on April 07, 2023, 07:55:53 am
I have the same item like this. Mod to Atmega328 with ...
The value of any measuring instrument is determined by its accuracy in relation to reference values.
I did not find a similar capacitor in my arsenal. For example, the readings of such capacitors on the firmware of both authors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hoangtran on April 07, 2023, 08:22:13 am
In my pics, there is a big difference in ESR measuring between the original firmware (8.19 ohm) and the m firmware (0.14 ohm). And the ESR results of m firmware and DE-5000 are nearly equal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on April 07, 2023, 05:30:03 pm
Have you calibrated the component tester before and after flashing the OSHW firmware? and again when alternating between the ZIF socket and the test leads? This is an important step to do every time to change the environment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 07, 2023, 07:26:38 pm
In my pics, there is a big difference in ESR measuring between the original firmware (8.19 ohm) and the m firmware (0.14 ohm). And the ESR results of m firmware and DE-5000 are nearly equal.
Regarding Transistor Testers with their original Chinese factory firmware:

It is always necessary to "short the probes" and then press "Start" to perform the "self-test" before expecting accurate test results. Chinese firmware performs "self-test" for 15 to 60 seconds and then displays a message instructing the user to "isolate probes" (remove the short) and then the self-test continues for another 20 to 60 seconds before it finishes. Unlike open-source Transistor Tester firmware the Chinese firmware does not display intermediate "step-by-step" data screens during self-test. It may be necessary to perform "self-test" several times before getting accurate test results.

Many Transistor Testers with Chinese firmware are capable of selecting either English or Mandarin for the displayed language. This is (of course) desirable for Transistor Testers which are sold both inside Chinese-speaking countries and exported. For example I have an LCR-TC1 unit (MCU is LGT8F328P) where holding down "Start" button for 5 to 10 seconds changes the displayed language between English and Chinese characters.

Because Chinese display fonts occupy a substantial amount of flash, the Chinese software developers must remove large portions of the original Transistor tester code and/or greatly simplify it.

This most certainly impacts their accuracy and reduces their feature sets.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hoangtran on April 08, 2023, 12:14:42 am
In my pics, there is a big difference in ESR measuring between the original firmware (8.19 ohm) and the m firmware (0.14 ohm). And the ESR results of m firmware and DE-5000 are nearly equal.
Regarding Transistor Testers with their original Chinese factory firmware:

It is always necessary to "short the probes" and then press "Start" to perform the "self-test" before expecting accurate test results. Chinese firmware performs "self-test" for 15 to 60 seconds and then displays a message instructing the user to "isolate probes" (remove the short) and then the self-test continues for another 20 to 60 seconds before it finishes. Unlike open-source Transistor Tester firmware the Chinese firmware does not display intermediate "step-by-step" data screens during self-test. It may be necessary to perform "self-test" several times before getting accurate test results.

Many Transistor Testers with Chinese firmware are capable of selecting either English or Mandarin for the displayed language. This is (of course) desirable for Transistor Testers which are sold both inside Chinese-speaking countries and exported. For example I have an LCR-TC1 unit (MCU is LGT8F328P) where holding down "Start" button for 5 to 10 seconds changes the displayed language between English and Chinese characters.

Because Chinese display fonts occupy a substantial amount of flash, the Chinese software developers must remove large portions of the original Transistor tester code and/or greatly simplify it.

This most certainly impacts their accuracy and reduces their feature sets.

In this Chinese firmware, it looks like self-calibration has been cut off. I have tried many times, but only this result appears:
Title: Re: $20 LCR ESR Transistor checker project
Post by: hoangtran on April 08, 2023, 12:25:40 am
Have you calibrated the component tester before and after flashing the OSHW firmware? and again when alternating between the ZIF socket and the test leads? This is an important step to do every time to change the environment.

Yes, I know, but 8.19 ohm vs 0.14 ohm is not acceptable. And most importantly, I cannot run self-calibration with this Chinese firmware; it looks like they cut off that function.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 08, 2023, 10:03:35 am
In this Chinese firmware, it looks like self-calibration has been cut off. I have tried many times, but only this result appears
Please measure resistance of each 680 ohm probe resistor. There are 3 of these, each connected between a MCU pin and a test socket pin.

These 3 resistors must match each other within +/- 1 ohm.

I had a similar issue with a “kit” style Transistor Tester where the 3 resistors supplied with the kit measured as follows:  675, 676, 691 ohms. The resistor which measured 691 ohms was far enough out of range to  prevent my tester from entering “self test” mode. Instead, when powered up with 1-2-3 shorted it would only display the following test result:    “1 - [resistor] - 2 - [resistor] - 3”

Details in my earlier post:
   https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4726172/#msg4726172 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4726172/#msg4726172)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on April 08, 2023, 02:57:08 pm
Please measure resistance of each 680 ohm probe resistor. There are 3 of these, each connected between a MCU pin and a test socket pin.
Hi!
Because of your posting, I looked at the circuit board of the TC1 with the APT32F172K8T6 again.
It looks like the middle "1" connectors go somewhere different than the first "1".
The first goes to R4 (474 Resistor), while the middle ones go to U6 ("V05").
I can't see what's happening on the other side of the board because that's where the connector is soldered, but to me it looks like there are different "1"s.
Does anyone understand what's going on here?
Thank you.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 08, 2023, 04:21:54 pm
Have you checked for continuity between all the #1 test pins? U6 plus D1 is the overvoltage protection. Each test pin should be connected to an ADC pin, a 680 Ohms resistor, a 470 kOhms resistor, and one I/O pin of the SRV05-4 (U6).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on April 08, 2023, 04:40:44 pm
Have you checked for continuity between all the #1 test pins?
No, I have not. I was just looking at a photo of the inside of my device that I took earlier.
I've opened it up again now and checked continuity.
You're right, all #1's are connected.
On this occasion I also measured all resistors.
They are very close together (<1%).
Everything's ok.

Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: vk3em on April 08, 2023, 11:41:53 pm

I have the same item like this. Mod to Atmega328 with 1.48m firmware. Here is the result:

Can you provide details on how you modded to replace this mcu with the ATMEGA328?

Luke
Title: Re: $20 LCR ESR Transistor checker project
Post by: hoangtran on April 09, 2023, 01:48:37 am
In this Chinese firmware, it looks like self-calibration has been cut off. I have tried many times, but only this result appears
Please measure resistance of each 680 ohm probe resistor. There are 3 of these, each connected between a MCU pin and a test socket pin.

These 3 resistors must match each other within +/- 1 ohm.

I had a similar issue with a “kit” style Transistor Tester where the 3 resistors supplied with the kit measured as follows:  675, 676, 691 ohms. The resistor which measured 691 ohms was far enough out of range to  prevent my tester from entering “self test” mode. Instead, when powered up with 1-2-3 shorted it would only display the following test result:    “1 - [resistor] - 2 - [resistor] - 3”

Details in my earlier post:
   https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4726172/#msg4726172 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4726172/#msg4726172)

I have read your post before. Those resistors in my kit are good: 680, 680, 680.01.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hoangtran on April 09, 2023, 02:29:32 am

I have the same item like this. Mod to Atmega328 with 1.48m firmware. Here is the result:

Can you provide details on how you modded to replace this mcu with the ATMEGA328?

Luke

Yes, I can.

In the hardware: Replace LGT8F328P with ATmega328P. Wiring pin 3 and 21 to GND; pin 6 and 18 to +5V.

Here is a change in makefile:
Code: [Select]
FREQ = 16

In config.h
Code: [Select]
#define HW_REF25
#define ZENER_R1         100000
#define ZENER_R2         10000
#define ZENER_UNSWITCHED
#define ZENER_BOOST_HIGH                  /* high active */
#define HW_PROBE_ZENER
#define ZENER_VOLTAGE_MAX     20000     /* max. voltage in mV */
#define HW_IR_RECEIVER
#define UI_ZENER_DIODE
#define BAT_DIRECT
#define BAT_OFFSET       0
#define BAT_WEAK         3600
#define BAT_LOW          3400
#define ADC_LARGE_BUFFER_CAP

In config_328.h
Code: [Select]
/*
 *  ST7735
 *  - 4 wire SPI interface using bit-bang SPI
 */
#define LCD_RES          PD1            /* port pin used for /RESX (optional) */
//#define LCD_CS           PD5            /* port pin used for /CSX (optional) */
#define LCD_DC           PD2            /* port pin used for D/CX */
#define LCD_SCL          PD4            /* port pin used for SCL */
#define LCD_SDA          PD3            /* port pin used for SDA */
#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_LATE_ON                     /* turn on LCD after clearing it */

#define TP_REF           PC5       /* test pin for 2.5V reference and relay */
#define TP_BAT           PC4       /* test pin for battery */
#define TEST_BUTTON      PD5       /* test/start push button (low active) */
#define IR_DATA          PD0       /* data signal */
#define BOOST_CTRL       PD7       /* control pin */

You can play around with other options as you want.

The schematic is based on MrSqueaky's work.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Vitaly_Ne on April 11, 2023, 12:35:21 pm
There was a need to measure megaohm resistors, and noticed a nuance. It immediately shows, for example, 4470k, and then at first faster, and then it grows more slowly ... after a minute, about 4495k ... if you wait even longer from about 2 minutes, it can grow to 4497k ... and stops.
Interested in the question: is this normal for measurements? if so, is it really necessary to measure large resistances for 2 minutes? Or is it some kind of accumulation in the controller (or a failure ... although everything else measures correctly ...)? When can a measurement be considered more or less correct? At the very end or when it starts to "slow down"?
I don't attach a photo, but I can, if necessary)))
I measured on different megaohm resistors ... 0.125W, 0.5W, 1W ..
The denominations are also from 2M to 4.7M ... everything is about the same in time ..
I apologize if this has been explained before (tell me the page?) .. just for the first time I measured megaohms, so it was embarrassing ...
Tester G328A(BGR), firmware 1.13 color(from Yuriy_K).
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on April 11, 2023, 01:00:32 pm
my jt lcr t7 jumps around resistance measurements also 3.3kohm resistor
3278
3286
3290
3290
3289
3286

I have calibrated it with the sorted 3 pin wire but i can't find the procedure i recall reading about how to calibrate it with a capacitor. i've searched through the ttester.pdf

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 11, 2023, 04:55:20 pm
There was a need to measure megaohm resistors, and noticed a nuance. It immediately shows, for example, 4470k, and then at first faster, and then it grows more slowly ... after a minute, about 4495k ... if you wait even longer from about 2 minutes, it can grow to 4497k ... and stops.
Interested in the question: is this normal for measurements? if so, is it really necessary to measure large resistances for 2 minutes? Or is it some kind of accumulation in the controller (or a failure ... although everything else measures correctly ...)? When can a measurement be considered more or less correct? At the very end or when it starts to "slow down"?
[...]
Tester G328A(BGR), firmware 1.13 color(from Yuriy_K).

From Karl-Heinz' documentation for the k-firmware:
Quote
If the ATmega has more than 8 KByte flash memory, the voltage measurement at the resistors will be delayed until no more changes are detected or the time limit is reached. With this method big capacitors are no more detected as resistors by mistake and the DC resistance of big inductors will be measured correctly.

I'd guess, an unstable Vcc (5V) could trigger that feature too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on April 11, 2023, 05:35:30 pm
... calibrated it with the shorted 3 pin wire but i can't find the procedure i recall reading about how to calibrate it with a capacitor. i've searched through the ttester.pdf

... you can find it at page 40, capter 3.3 Selftest and Calibration.

Regards

Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on April 11, 2023, 07:55:29 pm
I've read that already. I think my firmware does not have the WITH Samplin-
gADC = 1 enabled in the makefile. thanks anyway
Title: Re: $20 LCR ESR Transistor checker project
Post by: richtoy on April 12, 2023, 07:05:15 pm
Hi,

I have one of these cheap testers and decided to spend a rainy afternoon attempting a firmware update  ::)

The version of the device I have is LCR-TC1 with original 2.12k firmware; a ATMEGA324PA version with 16MHz crystal with exactly this schematic  https://www.eevblog.com/forum/oshw/chinese-tc1-transistor-tester/?action=dlattach;attach=1355798;image (https://www.eevblog.com/forum/oshw/chinese-tc1-transistor-tester/?action=dlattach;attach=1355798;image)

So from reading I see that I first need to update the firmware in U4, the STC15L104W.  The first thing I noticed is that the TX & RX are reversed in the P1 & P2 connections.  In the original schematic U4 pin 5 (tx) goes to P2 and pin 6 (rx) goes to P1 whereas is the schematic above they are reversed!

I downloaded the latest stc-isp (V6.91K) and eventually managed to update the firmware using the method described with the addition of the holding the button on the device down whist power is applied to force the 15L104 into boot mode.

Checking target MCU ...
  MCU type: STC15L104W
  F/W version: 7.2.5Q

Current H/W Option:
  . Current system clock source is internal IRC oscillator
  . Current frequency: 11.051MHz
  . Wakeup Timer frequency: 27.089KHz
  . Do not detect the level of P3.2 and P3.3 next download
  . Power-on reset, use the extra power-on delay
  . RESET pin behaves as IO pin
  . Reset while detect a Low-Voltage
  . Thresh voltage level of the built-in LVD : 2.42 V
  . Inhibit EEPROM operation under Low-Voltage
  . Hardware do not enable Watch-Dog-Timer
  . Watch-Dog-Timer pre-scalar : 256
  . Watch-Dog-Timer stop count in idle mode
  . Program can modify the Watch-Dog-Timer scalar
  . Do not erase user EEPROM area at next download
  . Do not control 485 at next download
  . Do not check user password next download
  . TXD is independent IO
  . TXD pin as quasi-bidirectional mode after reset
  . P3.3 output HIGH level after reset
  . Reference voltage: 1231 mV (Range: 1150~1320mV)
  . Testing time: 2017-9-28

  MCU type: STC15L104W
  F/W version: 7.2.5Q

Adjusting frequency ...         [1.031"]
Adjusted frequency: 12.011MHz (0.090%)

Re-handshaking ... Successful         [0.141"]
Current Baudrate: 38400
Erasing MCU flash ...  OK !      [0.359"]
Programming user code ... OK !      [1.375"]
Programming OPTIONS ... OK !      [0.063"]

H/W Option upgrade to:
  . Current system clock source is internal IRC oscillator
  . Current frequency: 12.011MHz
  . Do not detect the level of P3.2 and P3.3 next download
  . Power-on reset, use the extra power-on delay
  . RESET pin behaves as IO pin
  . Reset while detect a Low-Voltage
  . Thresh voltage level of the built-in LVD : 2.42 V
  . Inhibit EEPROM operation under Low-Voltage
  . Hardware do not enable Watch-Dog-Timer
  . Watch-Dog-Timer pre-scalar : 256
  . Watch-Dog-Timer stop count in idle mode
  . Program can modify the Watch-Dog-Timer scalar
  . Do not erase user EEPROM area at next download
  . Do not control 485 at next download
  . Do not check user password next download
  . TXD is independent IO
  . TXD pin as quasi-bidirectional mode after reset
  . P3.3 output HIGH level after reset
  . Reference voltage: 1231 mV (Range: 1150~1320mV)
  . Testing time: 2017-9-28
MCU ID : F2D400EC18041F

  MCU type: STC15L104W
  F/W version: 7.2.5Q

  . Set frequency: 12.000MHz
  . Adjusted frequency: 12.011MHz
  . Trim error: 0.090%


  Complete !(2023-04-12 17:49:36)

However, after successful flashing of the STC15L104W the tester no longer works.  It turns on as far as the title bar "M-Tester" but does nothing else and will not turn off!  Is this normal?

My intention is to build the full firmware on a RPi using the options that between lines 534-667 of the Clones.txt file in the firmware folder.  Has anyone done this?  Any pitfalls?

What is the procedure for flashing the main firmware?  Is the connection made via the U4 bit with EN shorted as power is applied to get the ATMEGA324PA into the correct mode?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 12, 2023, 07:12:57 pm
That's to be expected without the OSHW firmware. The 'main' firmware is programmed via the ATmega's ISP interface using an ISP programmer, e.g. USBasp or Arduino with the ISP sketch.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 12, 2023, 08:13:07 pm
]In this Chinese firmware, it looks like self-calibration has been cut off. I have tried many times, but only this result appears
Quote
I have read your post before. Those resistors in my kit are good: 680, 680, 680.01.
I looked inside my Transistor Tester clone which contains same LGT8F328P MCU as yours.

Edit: Sorry, I was looking at wrong photo. Your LGT8F328P unit does have same PC board as my unit

 However my unit has a totally different PC board (photo attached).

All of my Transistor Testers with Chinese firmware go straight into "self test" immediately after powering up with 1-2-3 shorted. This differs from OSHW firmware where "Start" button must be pressed a second time to enter self-test.

I intend to rework my LGT8F328P unit for ATmega328P with the instructions you provided. Thanks!  :clap:
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 12, 2023, 08:50:52 pm
Any suggestions regarding resetting the fuses would be welcome
Another method for recovering a bricked AVR is using an external clock/oscillator. I did a quick search and found these:

https://www.eevblog.com/forum/beginners/bricked-atmega-1284-with-avrdude (https://www.eevblog.com/forum/beginners/bricked-atmega-1284-with-avrdude)!-can-it-be-saved/
https://www.avrfreaks.net/s/topic/a5C3l000000UMBiEAO/t099084 (https://www.avrfreaks.net/s/topic/a5C3l000000UMBiEAO/t099084)
https://www.avrfreaks.net/s/topic/a5C3l000000UboeEAC/t159156 (https://www.avrfreaks.net/s/topic/a5C3l000000UboeEAC/t159156)
https://classbproject.com/fixes-and-hacks/recovering-a-bricked-avr/ (https://classbproject.com/fixes-and-hacks/recovering-a-bricked-avr/)

Connected it to an external 1 Mhz source(arduino), the mega324PA even has 125.0 kHz coming out of its PB1 pin. Running avrdudess with -b 1200 -B 56 (16 kHz SCK). Still unable to read signature, or change fuses.


Yes, I got it... Unbricking the avr(smd, 44 pin mega324PA) in-circuit is possible. Luckily most of the needed pins are present on the J7 header(H7 plus 2.1 board). Had to unsolder the onboard 10 kOhm reset resistor(to avoid frying the cpu with the 12 V). Also unsoldered the 6 pin display board(quite unnecessary I think), used arduino as prommer, and plenty jump-wires on abreadboard.
Don't want to clog the forum, but if someone needs it will provide step-by-step. Currently playing with the 1.48m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dirtmover on April 13, 2023, 03:58:48 pm
I have the same item like this. Mod to Atmega328 with 1.48m firmware. Here is the result:

Got the exact same device delivered last week, T7-PLUS-V2 with V3.1E FW . Only found this discussion a couple of days ago, wish I'd have found it before ordering.

So far noticed the capacitor esr, inductance and zener breakdown voltage is quite a bit off :(

Can you point me to some details of this mod.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 13, 2023, 09:59:49 pm
Got same device delivered last week, T7-PLUS-V2 with V3.1E FW . So far noticed the capacitor esr, inductance and zener breakdown voltage is quite a bit off :(
Does the PC board in your unit look exactly like either of my 2 attachments? Tan board or blue board?

Note that both units in my photos have 32-pin MCU (8 pins per side). Also there is a 16MHz crystal connected to the MCU. In both of my photos the MCU is “Logic Green” LGT8F328P.

I am asking because more companies are manufacturing Transistor Testers all the time. I’m trying to stay current with all the different variations which people are receiving.
Title: Re: $20 LCR ESR Transistor checker project
Post by: dirtmover on April 13, 2023, 11:41:00 pm
Does the PC board in your unit look exactly like either of my 2 attachments? Tan board or blue board?

This is mine, looks the same as your tan one
Title: Re: $20 LCR ESR Transistor checker project
Post by: hoangtran on April 14, 2023, 04:40:20 am
I have the same item like this. Mod to Atmega328 with 1.48m firmware. Here is the result:

Got the exact same device delivered last week, T7-PLUS-V2 with V3.1E FW . Only found this discussion a couple of days ago, wish I'd have found it before ordering.

So far noticed the capacitor esr, inductance and zener breakdown voltage is quite a bit off :(

Can you point me to some details of this mod.

I shared here in this post: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4804496/#msg4804496 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4804496/#msg4804496)
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on April 14, 2023, 07:19:32 am
I bought a brand new ATMega644P, when I program it for the first time with a 20Mhz external crystal what fuse settings do I need to use?

This is what I used for ATMega328p

avrdude -c usbasp -p m328p -B 12.0 -e -U flash:w:"ComponentTester.hex":i -U eeprom:w:"ComponentTester.eep":i -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 14, 2023, 07:46:32 am
Those fuse bit settings work for the ATmega644 too. But please change the efuse to 0xfc and ignore avrdude's warning about it (known issue, mistake in avrdude's config file).
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 14, 2023, 08:01:41 am
Edit: Found the issue.   Needed to install Winavr as windows was missing some bits. But it still did not make an eeprom file of a cfg file.


I have built my AYAT model with precision resistors, 0.1% voltage regulator and a 16mhz crystal, and need firmware. Well all I need is to change the clock from 8Mhz to 16MHz

Is there any way to use the makefile to output a .hex and .eep with windows 10 or is it linux only?

I downloaded the full 1.42m files just to see if I could output the hex files, and when I use the make command using the mingw program all I get is a heap of error messages. Which from prior experience seems par for the course when trying to do this with Windows.

Quote
C:\transtester>make
The system cannot find the path specified.
avr-gcc -mmcu=atmega328 -Wall -I. -Ibitmaps -DF_CPU=16000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -mcall-prologues -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT main.o -MF dep/main.o.d -c main.c
process_begin: CreateProcess(NULL, avr-gcc -mmcu=atmega328 -Wall -I. -Ibitmaps -DF_CPU=16000000UL -DOSC_STARTUP=16384 -gdwarf-2 -std=gnu99 -Os -mcall-prologues -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -MD -MP -MT main.o -MF dep/main.o.d -c main.c, ...) failed.
make (e=2): The system cannot find the file specified.
Makefile:209: recipe for target 'main.o' failed
make: *** [main.o] Error 2
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 14, 2023, 08:46:02 am
Obligatory photo's.  My soldering is a bit ordinary.  I am still relearning that skill.
[attachimg=1]
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 14, 2023, 10:44:20 am
Hi all,
I'm encountering a peculiar problem that was there with the original firmware, and also showing with the 1.48m. T7-plus v1.1 board, mega324pa with the 27V voltage source(no transformer).
If I measure higher voltage zeners, it displays correct. For lower values- below 10V, it displays way lower- i.e. 3-4 times lower(but the voltage drop over the zener while measuring is correct).
I cannot perform calibration(having issues with the single button- only working to start, but no redo), but I think this has nothing to do with [RC] calibration?
Where can I manually touch the calculation?
The zener resistors were checked(100k and 12k), the voltage references are ok too.

These -afaik, are just to define the "working range", out of which the part is declared "not a zener"
#define ZENER_VOLTAGE_MIN     1000      /* min. voltage in mV */
#define ZENER_VOLTAGE_MAX     24000     /* max. voltage in mV */

And fiddling with these(which are correct):
#define ZENER_DIVIDER_CUSTOM
#define ZENER_R1         100000
#define ZENER_R2         12000
Only makes things worse. Is there an off-set I am not aware of?

Title: Re: $20 LCR ESR Transistor checker project
Post by: gipetto on April 14, 2023, 10:47:11 am
Maybe this is a silly idea but if anyone wanted to fix the situation with the clone mcu then one way would be to clone the clone testers, but with a second footprint for a dip or smt mcu. it wouldn't be much more expensive for manufacturers to build, and if someone wanted to upgrade, they could cut the traces to the logic green and drop in their mcu and crystal.
If they open sourced the design, then there would be a standard sellers would follow for more sales, same way as how the ay-at is the best seller now.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 14, 2023, 12:06:32 pm
I cannot perform calibration(having issues with the single button- only working to start, but no redo), but I think this has nothing to do with [RC] calibration?

Press the button twice to enter the menu. This and the self-adjustment process is explained in the README file.   
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 14, 2023, 12:09:56 pm
Is there a dummies guide on how to compile the firmware, now I see 1.49m  just got released a few minutes ago. I am not sure what the flashlight is all about.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 14, 2023, 12:11:17 pm
Is there any way to use the makefile to output a .hex and .eep with windows 10 or is it linux only?

Please see https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/2475/ (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/2475/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 14, 2023, 12:16:22 pm
Get your ISP programmer ready! ;)

v1.49m:
- Alternative pinouts for IR receiver module (SW_IR_RX_PINOUT_G_V_D, SW_IR_RX_PINOUT_D_G_V, SW_IR_RX_PINOUT_D_V_G, suggested by boleslaw_43@mikrocontroller.net).
- Fixed capacitor detection issue in ESR tool. Happened after a semiconductor was found before by normal probing (reported by indman@EEVblog).
- Fixed bug in configuration management for touchscreens.
- Added check for frequency counter options to config_support.h.
- Moved code for counter tools from tools_signal.c to new tools_counter.c.
- Added checks for SPI_PIN and SPI_MISO to config_support.h in case bit-bang SPI with read support is enabled. Also extended SPI section in all
  config_<MCU>.h for easier handling.
- SW_R_TRIMMER shows now also the ratio of the second resistor (suggested by wandows@EEVblog).
- Display OneWire device symbol in DS18B20, DS18S20 and DHTXX tool (UI_ONEWIRE, suggested by indman@EEVblog).
- Added symbol for OneWire devices to all symbol sets (thanks to indman@EEVblog).
- Support for temperature sensor DS18S20 (SW_DS18S20, DS18S20_HIGHRES, suggested by indman@EEVblog).
- Added checks for Darlington BJTs to CheckProbes() & CheckDepletionModeFET() to prevent false detection as JFET in case EMI issues cause a high leakage current (reported by wandows@EEVblog).
- Fixed bug in check for Germanium PNP BJTs in CheckDepletionModeFET().
- Added configuration switch for sequential COM pin layout to OLED drivers for SH1106 and SSD1306 (LCD_COM_SEQ), and a switch for reversed COM mapping to the SSD1306 driver (LCD_COM_REMAP, suggested by boneDragon@EEVblog).
- Added support for a passive buzzer (BUZZER_ACTIVE or BUZZER_PASSIVE, suggested by boneDragon@EEVblog).
- Texts in Brazilian Portuguese (thanks to wandows@EEVblog).
- Added general purpose switched output, e.g. for an LED flashlight (HW_FLASHLIGHT, suggested by boneDragon@EEVblog).

Please download at
- https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
- https://github.com/kubi48/TransistorTester-source/tree/master/Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 14, 2023, 12:31:05 pm
now I see 1.49m  just got released a few minutes ago. I am not sure what the flashlight is all about.

It's a simple switched output controlled via the menu, e.g. for switching an LED (hence the name). Even smartphones have a flashlight app. ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 14, 2023, 01:21:08 pm
Is there any way to use the makefile to output a .hex and .eep with windows 10 or is it linux only?

Please see https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/2475/ (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/2475/)

Thanks.  Some of the links are dead but I managed to find the avr GNU8 toolchain from the microchip website.

I was still getting an error message as the eeprom was not getting made.   But the solution is here https://www.youtube.com/watch?v=5JpNGKeIOn8 (https://www.youtube.com/watch?v=5JpNGKeIOn8)

I will have to research ans configure the firmware for my device.  My first attempt has given me a white screen and that is all. But at least I can compile and upload it now. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on April 14, 2023, 06:02:34 pm
Thanks madires.

Attached update of the Spanish language file for those interested.

All the best.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jacon on April 14, 2023, 07:58:21 pm
Hi Marcus,

Attached please find updated Polish translation.

BTW - my ordinary '328 configuration reached 32764 bytes (sic!) this time...

Great work as always  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 15, 2023, 12:00:35 am
No idea how to use it, but it is there.   ;D

But my tester does this and I am not sure why.  I assume a hardware build error.  Sometimes with nothing installed it will say there is a resistor, always between pins two and three.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 15, 2023, 06:52:07 am
But my tester does this and I am not sure why.  I assume a hardware build error.  Sometimes with nothing installed it will say there is a resistor, always between pins two and three.
This is not surprising, because in your photos I see a lot of unwashed flux. This device has a high sensitivity, so any dirt, flux between the test contacts is perceived as resistance. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 15, 2023, 08:48:10 am
Thanks, I did think I had cleaned the board enough.  It would explain the erratic nature of the issue.   Given it a good clean now and all is good.

Now that I have worked out this compiling and programming I am blown away at the number of options in the config.h file. There seems to be a lot of fine tuning option where you can measure your device and put in correction figures, along with way too many things to enable everything on a little AT328P

It leaves the FNIRSI clone tester for dead and is only AU$10 more expensive.  I just need to find a good case to print out.

And who needs a torch option. :)






Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on April 15, 2023, 05:39:37 pm
Has anyone got the passive buzzer to work?  tried enabling the passive buzzer options and connected to the port in config_MCU.h, but get no sound when probing, using the piezo type like in the photo below.   :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 15, 2023, 06:57:40 pm
I tested a few passive buzzers and boneDragon tested too. Do you have a scope to check the output signal? Do you know the voltage specs of your buzzer?
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on April 15, 2023, 09:52:34 pm
I tested a few passive buzzers and boneDragon tested too. Do you have a scope to check the output signal? Do you know the voltage specs of your buzzer?

Doh, found my mistake, didn't uncomment #define HW_BUZZER as well, works fine now.  :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 16, 2023, 10:23:07 am
I have updated the Russian translation of the pdf documentation for version 1.49m as well as the language file. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on April 16, 2023, 12:38:22 pm
Madires, thank you very much for the new version. Everything works great, but there is a small remark. When measuring electrolytic capacitors, there is a "dead zone" up to about 0.03 ohm. Maybe it's on my Mega644, please check everyone who installed the new 1.49m version...
The picture shows the measurements of two different capacitors at different frequencies.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 16, 2023, 01:03:03 pm
You're welcome! There are no changes in the actual ESR measurement functions for quite a while.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on April 16, 2023, 03:46:13 pm
Get your ISP programmer ready! ;)

v1.49m
Since v1.47m we have symbols_32x39_hf in the bitmaps folder but don't have "#define SYMBOLS_32X39_HF" lines in config-<MCU> files. An oversight?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 16, 2023, 04:11:32 pm
Since v1.47m we have symbols_32x39_hf in the bitmaps folder but don't have "#define SYMBOLS_32X39_HF" lines in config-<MCU> files. An oversight?
No, this is not an oversight. This symbols set is relevant for displays with a higher resolution of 320x240 and higher.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 16, 2023, 04:44:19 pm
The long answer: The 32x39 symbol set is the companion of the 16x26 font. 39 pixels resized by a factor of two creates a symbol 78 pixels high. This matches three text lines with a height of 26 pixels each (26 * 3 = 78).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on April 16, 2023, 04:51:26 pm
The long answer: The 32x39 symbol set is the companion of the 16x26 font. 39 pixels resized by a factor of two creates a symbol 78 pixels high. This matches three text lines with a height of 26 pixels each (26 * 3 = 78).
Sorry! 
I searched  '32x39' in my config_644.h file but forgot that it's my moded file with irrelevant display sections removed  :palm:
I see that in the original config_644 there are 32x39 symbol options.

Anyway, thanks again for the new version!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Polf on April 17, 2023, 02:06:14 am
Please tell me for what reason an error occurs Process Exit Code: 2 during compilation?
But if you disable the menu CFLAGS += -DWITH_MENU, compilation is successful.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 17, 2023, 10:14:56 am
Let's see. It's about k-firmware and it's a warning about a potentially uninitialized variable, not really an error. I guess that the compiler is called with the option to treat warnings as errors and then returns 2. A simple solution would be to initialize the variable:
Code: [Select]
  unsigned long wish_freq = 0;
Title: Re: $20 LCR ESR Transistor checker project
Post by: Polf on April 17, 2023, 10:56:29 am
Thank you for your reply! Today I have successfully compiled on another PC with Windows 7 64 bit operating system installed. This means that after updating Windows 10 64-bit on the main  PC, my compiler does not work correctly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 17, 2023, 11:49:01 am
What do I need to enable to test Zeners on the AY-AT through hole model?  When I built my tester, I made sure the 180k and 20k resistors were well under 1% accuracy. 

The config has these options it seems

//#define HW_ZENER




//#define ZENER_DIVIDER_CUSTOM
//#define ZENER_R1         180000
//#define ZENER_R2         20000




//#define ZENER_UNSWITCHED




//#define ZENER_SWITCHED
//#define ZENER_BOOST_HIGH                /* high active */
//#define ZENER_BOOST_LOW                 /* low active */




//#define HW_PROBE_ZENER
//#define ZENER_VOLTAGE_MIN     1000      /* min. voltage in mV */
//#define ZENER_VOLTAGE_MAX     30000     /* max. voltage in mV */




---------------------------------------------------------------------------------------------------------------------------------

Thank you for your reply! Today I have successfully compiled on another PC with Windows 7 64 bit operating system installed. This means that after updating Windows 10 64-bit on the main  PC, my compiler does not work correctly.

I am running windows 10, 64 bit and have managed to get it to work.

I followed sort of this guide that madires kindly linked for me  https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/2475/

 the link for toolchain would not work for me (funnily enough it does now) and I ended up getting version avr8-gnu-toolchain-3.7.0.1796-win32.any.x86_64

I am using WinAVR on windows 10 and when I tried to compile I got an error message, the fix was to go to the installation folder for winavr on the C: drive and search for patch.exe

If you run that it opens a command prompt page.   You have to leave it open and go back to the winavr running program and it should compile. Or mine does anyway.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vk3em on April 17, 2023, 12:08:06 pm
Yes, I know, but 8.19 ohm vs 0.14 ohm is not acceptable. And most importantly, I cannot run self-calibration with this Chinese firmware; it looks like they cut off that function.
I can confirm the same problems. The printed quick start guide includes instructions for "Self-Calibration" but its not possible to get it to enter that mode. I have tried all combinations. The instructions show screen shots of firmware including self-calibration mode that is "2.xx" while the shipped firmware is "3.xx" - the lack of self-calibration mode may or may not be the cause of the erroneous readings, but on my unit as well, the ESR readings seem totally wrong, which is a real shame as ESR measurement of capacitor was the reason I purchased it! Might have to get a real ESR meter now. :)

Luke
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 17, 2023, 12:15:04 pm
What do I need to enable to test Zeners on the AY-AT through hole model?  When I built my tester, I made sure the 180k and 20k resistors were well under 1% accuracy. 

The AY-AT doesn't come with a boost converter, it just measures an external voltage via a 10:1 voltage divider. So the only option to enable is HW_ZENER. If you want to check Zener diodes you would have to apply an external power source (<50V and a current limit of a few mA). The recommended settings for the AY-AT are listed in the Clones file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hoangtran on April 18, 2023, 01:27:01 am
Yes, I know, but 8.19 ohm vs 0.14 ohm is not acceptable. And most importantly, I cannot run self-calibration with this Chinese firmware; it looks like they cut off that function.
I can confirm the same problems. The printed quick start guide includes instructions for "Self-Calibration" but its not possible to get it to enter that mode. I have tried all combinations. The instructions show screen shots of firmware including self-calibration mode that is "2.xx" while the shipped firmware is "3.xx" - the lack of self-calibration mode may or may not be the cause of the erroneous readings, but on my unit as well, the ESR readings seem totally wrong, which is a real shame as ESR measurement of capacitor was the reason I purchased it! Might have to get a real ESR meter now. :)

Luke

Because of this long thread, I was curious, so I picked one to try. Now it's gone. And yes, a real ESR meter is a serious thing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vk3em on April 18, 2023, 06:16:29 am

Yesterday I ordered another unit which just might contain the ATmega324. These things are cheap enough that I'll keep at it until I get the one I want!


Call me a sucker for punishment, but after recently failing with my purchase of the LCR-TC2 from this vendor (I wanted an ATmega324 but got the LGT8F328P), I've taken a gamble on the LCR-TC1 model from the same vendor. https://www.aliexpress.com/item/1005004717377243.html (https://www.aliexpress.com/item/1005004717377243.html)

What gives me hope?

Quote
LCR-T7 / LCR-TC1:color screen / M644 chip, two functions are the same! T7 is slightly faster! The TC1 screen is slightly larger and they are all powered by lithium batteries. In addition to measuring resistance, capacitance, inductance, diodes, MOS transistors, thyristors, it can also measure additional voltage regulators, infrared decoding (limited to for Hitachi format)
Self test with automatic calibration

In the LCR-TC2 description, it does not mention M644 (since it was delivered with LGT8F328P that makes sense) nor does it mention "Self test with automatic calibration" - this also makes sense as firmware for the LGT8F328P (in my case V3.1e) cannot fit the code for self-calibration. V3.1E firmware is also horrifically buggy, cannot reliability measure ESR, or Darlington transistors, etc. I will definitely be modifying my LCT-TC2 with LGT8F328P to the ATmega328P.

I can only presume (hope) M644 mentioned in the details of the LCR-TC1 description refers to ATMega644 and so far this is the only specific mention of M644 within an advertisement that I can find. Lets see when it arrives.

Luke

Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 18, 2023, 06:53:46 am



What gives me hope?

ha ha, well I now have gone from zero testers a month ago to two and another currently on a plane.  Then I bought six resistors for $2.57 each and six for $1.60 each to "fix up the kits" Along with a couple of precision voltage regulators and a couple of precision voltage references.

I think I am up around $80 now for the three units and the fnirsi one is just a basic basic thing.  Although in passing I wonder instead of spending large sums on through hole precision resistors.   0.1% SMD's are only a dollar each, I wonder if I could have soldered wires to them and used them instead.

Now I am thinking for zener diodes is there a boost converter module I could use to apply the required boost voltage.  Hide it in a 3d printed case connected with the battery.

The other downside is the small memory I can not fit the entire spread of options into one device. (so you do need multiple anyway) or one with the bigger chip.

-----------------------------------------------------------------------------------------------



Makes me wonder about this one as I can not find a reference to this design in the clone list.  One listing I saw had a review where a photo of the rear of the board and it showed the same as the attached photo below.

https://www.aliexpress.com/item/1005005137402266.html (https://www.aliexpress.com/item/1005005137402266.html)

This a photo of the board from the internetz.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 18, 2023, 06:58:00 am
Makes me wonder about this one as I can not find a reference to this design in the clone list. 
You don't need to think about this design as it is of no interest due to the poor quality BGR display. ;)
Similarly, with similar clones, where such a display is used.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 18, 2023, 09:31:02 am
ha ha, well I now have gone from zero testers a month ago to two and another currently on a plane.  Then I bought six resistors for $2.57 each and six for $1.60 each to "fix up the kits" Along with a couple of precision voltage regulators and a couple of precision voltage references.

Wow, that's expensive! A local online shop sells 0.1% TH resistors (Yageo) in single quantity for around EUR 0.25 - 0.30 (680 and 470k are 0.27).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 18, 2023, 09:43:08 am
0.1% SMD's are only a dollar each, I wonder if I could have soldered wires to them and used them instead.
Maybe I'm wrong, 0.1% resistors are good, but for this project it is quite enough to select measuring resistors from the 1% set with a multimeter. This selection is then easily controlled using the built-in hardware tests T1-T6. It's just important that the pairs of resistors are close in resistance. I didn't notice much difference in readings compared to 0.1% precision resistors. Do not forget that this is just a SIMPLE TESTER, in which there are still a lot of factors that do not allow equating it to metrological instruments. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 18, 2023, 10:18:09 am
I was just being guided by others on ways to improve on the chinese kits  https://github.com/blurpy/transistor-tester/blob/master/resources/AY-AT-J1.3.png

Is this the way to check zeners on this model.    It was a 12V Zener.   40V being input, 28V showing, so 12V Zener?

I only enabled  HW Zener
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 18, 2023, 01:35:14 pm
Nice! ;D Connect the Zener diode and the external power supply in parallel to the tester's input, while limiting the current to a few mA (typically 3 mA).
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 18, 2023, 01:40:20 pm
OK, I connected PD0 of my mega324pa(which is a configuration pin, pulled up to 5V, not used in m-firmware) to the test button, and can now use the test button properly. I did the Test, and Adjustment(now with the 1.49m) number of times, completed successfully, and saved in Profile1.
However the issue persists: 1. Zener diodes over 10 V are measured perfectly, below 10 V(or thereabout) are shown as ~1/4th of their voltage.
2.Resistors are shown in a very strange way: I put a brand new 10 kOhm(which measures 4247 Ohm after Adj) multiturn pot, and starting from 0 slowly go up. I get this in Ohms: 0.91, 70.5, 535.6, 960.2, 1224, 1610, 2104, 2424, 2601, 11.59k, 12.72k, 14.07k, 15.23k, 16.60k, 18.20k, 2418, 2569, 2854, 3043, 3329, 3615, 3862, 4187, 4322(at the end).
I.e. going linnearly, albeit low, then for a while overshooting by double, then back to low, and finnishing at around half the actual value.

Please be aware that this is NOT A FIRMWARE ISSUE, since it had a similar behaviour with the original Chinese firmware.
I would like an opinion whether this is a hardware defect(why does it complete the Adjustment then?), or a wrong port pin specified somewhere(checked number of times, schematic is very similar to the T7 in the Clones memo)?
I have checked the resistance of the 3 probes, and the readings are practically the same to GND and VCC for all 3. Also the resistance of the 3 680 Ohms, and 470 kOhms are within 0.1% of each other.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 18, 2023, 02:18:50 pm
Could you please repeat the Zener test (with a Zener <10V and another one >10V) and measure Vcc (5V) with a DMM? Is Vcc stable?
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 18, 2023, 02:55:05 pm
Is this the way to check zeners on this model.    It was a 12V Zener.   40V being input, 28V showing, so 12V Zener?
Another method is this:

1) Connect a 10k ohm resistor instead of the zener shown in your photo. Temporarily set the zener diode aside (not connected). Otherwise keep same connections to your 40V power supply. After replacing zener with 10k resistor then the Transistor Tester should display the DC voltage provided by your power supply (~40V).

2) Next, connect the zener to be tested directly across the 2 “voltage test” terminals of the Transistor Tester, with zener cathode (banded end) to + terminal of voltage test connector.

3) Transistor Tester should then display the actual zener voltage (12V). You won’t need to subtract the voltage displayed by the Transistor Tester from the power supply voltage to obtain the zener voltage.

The 10k series resistor limits the maximum zener test current to <4mA (when external power supply voltage is 40V).

Most  “factory built” Transistor Testers with self-contained zener test feature use a 10k series resistor to limit the test current. Although the Transistor Tester technical reference manuals provide a schematic for an optional “constant current source” for zener testing, I don’t think this extra complexity is necessary. The 10k series resistor all by itself is adequate.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 18, 2023, 03:27:57 pm
Call me a sucker for punishment, but after recently failing with my purchase of the LCR-TC2 from this vendor (I wanted an ATmega324 but got the LGT8F328P), I've taken a gamble on the LCR-TC1 model from the same vendor. https://www.aliexpress.com/item/1005004717377243.html (https://www.aliexpress.com/item/1005004717377243.html)
What gives me hope?
Quote
LCR-T7 / LCR-TC1:color screen / M644 chip
I succeeded at getting a unit containing a genuine Atmel ATmega324 in Jan. 2023. I purchased it from an eBay vendor who also offered several different Transistor Tester models, quite similar to the Aliexpress listing in your post.

The item I selected was priced at $23 USD vs. $12-15 USD for all other models offered by the same vendor. The eBay vendor described it as “LCR-TC2 improved” (I expected to pay ~$23 USD because genuine Atmel ATmega324 as bare IC chip sells for >$8 USD).

Curiously my mega324 unit also displays V2.3E for its firmware. I have confirmed it contains a genuine ATmega324 (44 pins, not 32). I’m nearly ready to install OSHW Transistor Tester firmware into it. I will post my results when finished upgrading.

Please let us know what arrives for you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on April 18, 2023, 04:33:30 pm
Is this the way to check zeners on this model.    It was a 12V Zener.   40V being input, 28V showing, so 12V Zener?

I only enabled  HW Zener

... connecting your z-diode is wrong for a measurement without calculation:

Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 18, 2023, 08:37:28 pm
Is this the way to check zeners on this model.    It was a 12V Zener.   40V being input, 28V showing, so 12V Zener?I only enabled  HW Zener
... connecting your z-diode is wrong for a measurement without calculation:
Is that a 20k ohm series resistor in your photo?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on April 18, 2023, 10:12:28 pm
... yes, it is - this prevents the BZX83C47 from heating up. With higher current, the zener voltage increases and the distance to the measuring voltage (50 volts) becomes too small to measure accurately - with this arrangement, the measuring current is approx. 250 µA!

Regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 18, 2023, 11:03:01 pm
Here are some pricey ones  https://www.aliexpress.com/item/1005003670951373.html (https://www.aliexpress.com/item/1005003670951373.html)

I want upgrade 3.  "After sales upgrade,New skin shrimps will be given away and accidentally burned within one year,"   :-DD

I think they mean a different firmware and a one year warranty.

I guess this is the same basic model without the accidentally burnt shrimp skins. https://www.aliexpress.com/item/1005003680113751.html (https://www.aliexpress.com/item/1005003680113751.html)

All claim 48V zener capability.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on April 19, 2023, 02:14:44 am
Here are some pricey ones  https://www.aliexpress.com/item/1005003670951373.html (https://www.aliexpress.com/item/1005003670951373.html)I want upgrade 3.  "After sales upgrade,New skin shrimps will be given away and accidentally burned within one year,"   :-DD
Interesting that this vendor posts photos of the PC boards. Most do not. Also all 3 of their PC board photos show MCU chips with 44 pins. To the best of my knowledge there aren’t (yet) any cloned/faked Atmel MCU chips with 44 pins. Popular “fake” Atmel MCU chips all have 32 pins. Yet another “tell” is the presence of j4, a 6-pin Atmel ISP programming header in the traditional 2x3 pin format. Transistor Tester PC boards with clone/fake MCU never have this 2x3 pin programming header. Some do have what appears to be a programming header, but never in the 2x3 pin style.

Chinese-> English is often entertaining. For example:

https://www.ebay.com/itm/324243157482 (https://www.ebay.com/itm/324243157482)

Quote
Product parameters:
Product Type: Electronic Tube Amplifier
Number of channels: two channels
Output rent resistance: 4-8 euros
Power supply: AC12V
Product net weight: 170g
Product size: 81*81*43MM
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 19, 2023, 05:43:30 am
Could you please repeat the Zener test (with a Zener <10V and another one >10V) and measure Vcc (5V) with a DMM? Is Vcc stable?

Sorry about the mess on the desk! See attached measurement of an 8.2 V Zener with the dmm over the diode.One with the dmm over the VCC.
Another with a 16 V Zener. And one with empty test terminals.
I can put a trace scope on the VCC if needed, but it looks pretty steady. |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 19, 2023, 07:51:45 am
However the issue persists: 1. Zener diodes over 10 V are measured perfectly, below 10 V(or thereabout) are shown as ~1/4th of their voltage.
Please be aware that this is NOT A FIRMWARE ISSUE, since it had a similar behaviour with the original Chinese firmware.
In this case, show us the compiled firmware and the configuration files you used.
It will also be nice if you show the results of hardware tests T1-T6 from the Selftest item.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 19, 2023, 08:41:48 am
However the issue persists: 1. Zener diodes over 10 V are measured perfectly, below 10 V(or thereabout) are shown as ~1/4th of their voltage.
Please be aware that this is NOT A FIRMWARE ISSUE, since it had a similar behaviour with the original Chinese firmware.
In this case, show us the compiled firmware and the configuration files you used.
It will also be nice if you show the results of hardware tests T1-T6 from the Selftest item.

See attached makefile, config.h, config_644.h, .hex file, and .eep file in one archieve.
Second archieve has screenshots of each stage of Self Test, as well as the Show Values screen.
The T4 stage did not show any values, but flickered very quickly, before asking to "remove short".
Didn't want to upload a video. Hope this is what you needed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 19, 2023, 09:04:33 am
Second archieve has screenshots of each stage of Self Test, as well as the Show Values screen.
Well, a hardware problem was immediately discovered in the T2-T3 tests. In the photo, I highlighted with a red question the values ​​that indicate a problem with the measuring resistors or controller ports. The values ​​in these tests should always be of the same order and close in value. Now you must remove all the extra wires that you use for the ZIF panel and also power the tester not from an external source, but from a 3.7V battery. Then repeat tests T1-T6 and show us the results.
Show us also a good quality photo of the reverse side of your clone where is the microcontroller and parts?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 19, 2023, 10:01:13 am
I completely forgot one more thing. Such poor readings in the T2-T3 tests can be caused by a faulty SRV05-4 protective assembly. Remove it for a while and repeat the hardware tests again. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 19, 2023, 11:08:37 am
Sorry about the mess on the desk! See attached measurement of an 8.2 V Zener with the dmm over the diode.One with the dmm over the VCC.
Another with a 16 V Zener. And one with empty test terminals.
I can put a trace scope on the VCC if needed, but it looks pretty steady. |O

So Vcc is stable and the problem is somewhere else. Please follow indman's suggestions next.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 19, 2023, 11:12:44 am
I completely forgot one more thing. Such poor readings in the T2-T3 tests can be caused by a faulty SRV05-4 protective assembly. Remove it for a while and repeat the hardware tests again. :)

Thanks, I will try removing the OV protection.
With the battery back, and Self Test performed(all T readings are basically the same), the zener/resistor issue is still present.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 19, 2023, 02:19:08 pm
Thanks, I will try removing the OV protection.
With the battery back, and Self Test performed(all T readings are basically the same), the zener/resistor issue is still present.
[/quote]

No luck with the DZ1 chip removed, I'm afraid! Re-did the tests, similar results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 19, 2023, 02:26:46 pm
No luck with the DZ1 chip removed, I'm afraid! Re-did the tests, similar results.
Have the test results not changed at all, exactly the same as before?
One more question - why did you change the port for the Test button from PD2 to PD0?
Title: Re: $20 LCR ESR Transistor checker project
Post by: vk3em on April 19, 2023, 02:40:37 pm
ha ha, well I now have gone from zero testers a month ago to two and another currently on a plane.  Then I bought six resistors for $2.57 each and six for $1.60 each to "fix up the kits" Along with a couple of precision voltage regulators and a couple of precision voltage references.

Wow, that's expensive! A local online shop sells 0.1% TH resistors (Yageo) in single quantity for around EUR 0.25 - 0.30 (680 and 470k are 0.27).

E96 resistor values are more common in 0.1% than E12 where 0.1% values are non standard. Look for 681 Ohms (instead of 680) and 475 kOhms (instead of 470k).

Luke
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 19, 2023, 02:51:43 pm

Have the test results not changed at all, exactly the same as before?
One more question - why did you change the port for the Test button from PD2 to PD0?
[/quote]
They look pretty identical...

I could never get the Test Button to operate properly via the U3(as in my board) chip. I re-programmed it as stated, but could not get it to go low on pin8(i.e. PD2 on the MCU). So using it before only woke-up the tester, but could not enter the menu, so only usable way was to program it as "continuous".
I know replacing it with the 2 transistors will be better(also gaining a port), that's coming next, but I don't think this affects the measurements.

Tomorrow I will check the battery port if it can measure low voltage, since it is adjacent to the zener port. And the zener port is indeed failing in [low] voltage measurement. As to the weird resistor results- no idea what to do yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 19, 2023, 02:58:41 pm
They look pretty identical...
I could never get the Test Button to operate properly via the U3(as in my board) chip. I re-programmed it as stated, but could not get it to go low on pin8(i.e. PD2 on the MCU).
These strange and incorrect test data quite convincingly hint at a hardware problem with your tester. It is very likely that your controller is damaged or defective. Try the 2-transistor control option. If you have already checked the 680Ω and 470kΩ resistors and they are OK to I have no more ideas how to fix this problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on April 19, 2023, 07:03:20 pm
... no idea what to do yet.

... my suggestion is to swap the "small" Atmega324 for a 644 or 1284!!

Greeting Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 20, 2023, 09:33:19 am

[/quote]

... my suggestion is to swap the "small" Atmega324 for a 644 or 1284!!

Greeting Horst
[/quote]

Very nice job, doubt it I'll be able to do it, without damaging the pcb. Add to it the "Chipgate".
..And where's the fun, if you don't [try and] get to the bottom of things :-/O
I set the zener input as a Battery Test(TP_BAT), and changed the BAT_LOW to 1 mV- so the CPU doesn't switch off. Next I put it on Continuous mode, and connect a multiturn pot, instead of a zener. I have attached the results of measuring the voltage at the pin(AFTER ALL DIVIDERS- RIGHT ON THE INPUT PIN) to ensure proper voltage reaches the ADC. You can see that the measuring pin is receiving the right voltage, and the displayed reading is pretty consistent- increasing by 0.03 for each input volt, until the "magic" 1 V threshold is passed, after which the measurement is correct, and the reading increases by 0.11/V.

My knowledge of AVR's is not much, but doesn't this look like hardware configuration issue, rather than a blown port- which would be "clipping" over/under certain voltage.

And a stupid question(all trolling welcome :-+): Why is the AREF pin connected to GND via a capacitor(and not directly, or via dc ref)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 20, 2023, 09:51:05 am
oitar,it would be nice if you made a short video showing the process of turning on the tester and the self-test procedure. Only with the condition of using very short jumpers to short the ZIF 1-2-3 test contacts.
I would also like to see what fuses are currently installed for your chip? Exactly those that are now being read from your chip.

Why is the AREF pin connected to GND via a capacitor(and not directly, or via dc ref)?
You can remove this capacitor entirely. What it is for is explained in detail in the documentation from Karl-Heinz:
"The new software version can use ADC voltage scaling. The switching speed depends on the external capacitor C1 on AREF (pin 21 of the ATmega328). To avoid slowing down by more than necessary, the capacitance of this capacitor must be reduced to 1nF. You can remove the capacitor C1 altogether."
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 20, 2023, 11:51:09 am
oitar,it would be nice if you made a short video showing the process of turning on the tester and the self-test procedure. Only with the condition of using very short jumpers to short the ZIF 1-2-3 test contacts.
I would also like to see what fuses are currently installed for your chip? Exactly those that are now being read from your chip.

Why is the AREF pin connected to GND via a capacitor(and not directly, or via dc ref)?

Indman, thank you for your help!

I made a video, including Start-up, Test, Adjustment, 2 zeners test, and Fuse-read. I is almost 5 min long, and about 11 MB after recoding.
Couldn't upload it here, due to the 4 MB limit, please check the link to my GDrive. Otherwise let me know if I should cut it to 3 pieces maybe.

https://drive.google.com/file/d/1_b-A_LHtR5gFB1j11Iy09tIkvR9vuGX2/view?usp=sharing
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 20, 2023, 12:01:15 pm

You must "share to all" this file so that others can watch it. It is not necessary to cut the video into parts.
[/quote]

Sorry, should work now! If I play it online it's upside down and reversed, but vlc plays it fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 20, 2023, 12:56:55 pm
Have the test results not changed at all, exactly the same as before?
They look pretty identical...
1.Here is a clear example of the fact that it is very useful to make a video that explains a lot.
I asked you if the readings of the hardware tests have changed? You said they haven't changed.
And on your video, I see that the results of hardware tests now look quite standard, which indicates that the controller's measurement ports are in perfect order.
2. Who prompted you to set the fuse values ​​that you now have?
Set the fuses as I showed in the screenshot, make sure they are registered correctly and do not touch them again!
3. We will deal with the measurement of zener diodes separately, after you set the fuses correctly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 20, 2023, 02:09:56 pm

[/quote]
1.Here is a clear example of the fact that it is very useful to make a video that explains a lot.
I asked you if the readings of the hardware tests have changed? You said they haven't changed.
And on your video, I see that the results of hardware tests now look quite standard, which indicates that the controller's measurement ports are in perfect order.
[/quote]

My apologies, should've made it more clear in my previous post:

Thanks, I will try removing the OV protection.
With the battery back, and Self Test performed(all T readings are basically the same), the zener/resistor issue is still present.
No luck with the DZ1 chip removed, I'm afraid! Re-did the tests, similar results.
[/quote]

[/quote]
2. Who prompted you to set the fuse values ​​that you now have?
Set the fuses as I showed in the screenshot, make sure they are registered correctly and do not touch them again!
[/quote]

I put the values I've saved from the original F/W. Mentioned earlier that I had to unbrick it, because of wrong fuse values. After managing to parallel-program it in-circuit, decided that the original values are the safest.

[/quote]
3. We will deal with the measurement of zener diodes separately, after you set the fuses correctly.
[/quote]

The fuses are now exactly as you suggested. I made a number of Test/Adjustments, no improvement on the displayed results. Should I make a new video?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 20, 2023, 02:37:48 pm
The fuses are now exactly as you suggested. I made a number of Test/Adjustments, no improvement on the displayed results. Should I make a new video?
No, you don't need to make a video yet.
What will be the results when measuring zener diodes from the "Zener" menu item?
Remove diode D5 from the circuit and measure the Fluke voltage at the point I showed with the red arrow when measuring the 8.2V and 12V zener diode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 21, 2023, 05:55:50 am

[/quote]
No, you don't need to make a video yet.
What will be the results when measuring zener diodes from the "Zener" menu item?
Remove diode D5 from the circuit and measure the Fluke voltage at the point I showed with the red arrow when measuring the 8.2V and 12V zener diode.
[/quote]

Done.
While measuring 8.2V zener: at the highlighted point voltage is 0.892V(LCD showing 2230mV). While measuring the 12V zener(LCD showing 12.17V): 1.30V.
That's similar to the test I did yesterday with the D5 diode still in. You can see the 12V point( in the spreadsheet I posted ) is identical to the new measurement(with D5 out).

I re-run the test, using the Battery Test pin( PA5 ). Since this pin is connected to the battery, but via a 1MOhm resistor, one can short it progressively to GND without overloading the bat, to achieve all voltages between 0 and Vbat. The LCD reading behavior is identical to PA4: once the pin voltage crosses 1V downwards, the reading becomes way lower than the actual value. So the whole PA port is affected, and I'm sure this is the reason for the strange resistor measurements.

This pretty much confirms that I have a damaged/defective ADC then?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 21, 2023, 06:38:47 am
What will be the results when measuring zener diodes from the "Zener" menu item?
You didn't answer this question.
Show me a photo of the clone from the details side of how it looks at this point in time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on April 21, 2023, 07:14:04 am
This pretty much confirms that I have a damaged/defective ADC then?
Why did they do it in config_644.h
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 21, 2023, 07:28:36 am
Yuriy_K, In his config.h, the setting of a dedicated port for checking zener diodes is disabled
//#define ZENER_SWITCHED
, so the settings that you have shown do not affect the operation of the tester in this mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 21, 2023, 08:40:02 am
What will be the results when measuring zener diodes from the "Zener" menu item?
You didn't answer this question.
Show me a photo of the clone from the details side of how it looks at this point in time.

Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 21, 2023, 09:08:30 am
I saw something interesting...
Look at the 2 short videos. I'm measuring the voltage on the AREF pin(the one with the cap), while testing the 8.2V, and then the 12V zeners.
In the first case(8.2V) the voltage never goes over 4.3V at the beginning of every measurement, and drops further during the test.
In the 12V case the AREF clearly goes over 5V at the beginning of each measurement.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 21, 2023, 09:16:08 am
oitar, it is likely that ADC scaling is not working properly. Therefore, I propose several options for further action:
1. Remove capacitor C1 and repeat measurements without it. Does anything change?
2. Compile a new firmware, where the PA6 port will be assigned to measure the zener diodes. Apply external voltage(necessarily through a resistor divider) in the same way as you did before and check the response of this port.
3. You can try to upload firmware 1.13k.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on April 21, 2023, 06:07:12 pm
Adapter to upgrade the T-Tester with ATMEGA328 DIP28 to ATMEGA644 TQFP.
Idea and implementation by Boleslaw Jamroz from Poland,
I have only developed a circuit board for the cumbersome threading adapter
that simplifies the construction much ;-)
https://www.mikrocontroller.net/topic/transistortester-avr?goto=7398047#7381379 (https://www.mikrocontroller.net/topic/transistortester-avr?goto=7398047#7381379)
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 21, 2023, 11:24:33 pm
I found I had a small boost converter here.   It seems like it would work to supply voltage for zener diodes.

[attach=1]
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 22, 2023, 12:15:39 pm
My inductor measurements seem to be out as it seems to measure higher then the inductors say they are.   Are there any adjustments for inductance?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 22, 2023, 01:42:21 pm
Are there any adjustments for inductance?
What do you think for whom and why does the respected madires wasting his precious time and write detailed instructions(manual) in which he considers all the nuances of measuring resistors, capacitances, inductances and other details? I think for those who want to explore the possibilities of the project, and not just for themselves.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on April 22, 2023, 02:36:04 pm
Hello everyone.

I have a GM328 with the buzzer modification.
With v1.47m it works perfectly for me.
But with v1.49m, it's always ringing, and I've tried various things and it's always the same.

What could be the problem?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 22, 2023, 04:02:41 pm
My inductor measurements seem to be out as it seems to measure higher then the inductors say they are.   Are there any adjustments for inductance?

Please see the README file, section 'Inductors'!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 22, 2023, 04:07:44 pm
I have a GM328 with the buzzer modification.
With v1.47m it works perfectly for me.
But with v1.49m, it's always ringing, and I've tried various things and it's always the same.

What could be the problem?

Which buzzer related options have you enabled? Which pin have you set for BUZZER_CTRL (_PORT and _DDR) ? Is that pin also used for something else? Does the buzzer start ringing at power-on or when running a specific function?
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on April 22, 2023, 04:22:22 pm
I have not activated any function for the buzzer.
The buzzer starts to sound as soon as the equipment is turned on
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 22, 2023, 04:40:00 pm
Have you enabled HW_BUZZER? BUZZER_ACTIVE or BUZZER_PASSIVE? Which pin have you set for BUZZER_CTRL (_PORT and _DDR)? Or have you just connected the buzzer to some pin without enabling anything?
Title: Re: $20 LCR ESR Transistor checker project
Post by: carrascoso on April 22, 2023, 04:57:40 pm
Thank you, Madires, I already solved it.

What difference is there in the operation of BUZZER_ACTIVE or BUZZER_PASSIVE
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 22, 2023, 05:06:28 pm
BUZZER_ACTIVE: buzzer with integrated oscillator (makes sound when power is applied)
BUZZER_PASSIVE: simple piezo disc (needs external oscillator)
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 22, 2023, 09:02:36 pm

What do you think for whom and why does the respected madires wasting his precious time and write detailed instructions(manual) in which he considers all the nuances of measuring resistors, capacitances, inductances and other details? I think for those who want to explore the possibilities of the project, and not just for themselves.

Thanks for the help.   I simply did not see the reandme file in amongst the files in the download.  I did not ask the question frivolously.  I noticed in the .c files there are large amounts of explanatory text and I have been using that to fiddle around.  I searched through inductor.c and I did see something there, I also searched google for #define SW_INDUCTOR, and also searched this thread for the same. Coming up with nothing of consequence.

The reason I asked is the fnirsi clone (which is surprisingly accurate) seems to giving me a closer measurement on inductance and we simply cannot have a unit with a completely fake atmel chip doing that.

Anyway, I am now off to start a thread on how can I find a $50 oscilloscope, and what oscilloscope should I buy.

Thanks again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 24, 2023, 09:47:29 am
Have a matching pair now.

A tip for anyone building these.  The zif socket, you need to pull the lugs out a bit as you solder them otherwise the socket will rattle with use (found this out on the first built one).  I carefully used a pair of side cutters to gently pull on each lug as I soldered it. They pulled out about another 0.5mm or a tad more. 

Pics of results side by side with same component.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on April 24, 2023, 10:29:26 am
... the socket will rattle with use

... nice tip about the ZIF sockets (cheap China replica)!

... and, did you find a $50 oscilloscope??

Regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 24, 2023, 11:32:51 am
Nah, no time now for a $50 oscilloscope.  I have been too busy reading a readme file, changing configuration settings, compiling,  uploading, cursing when it says I have tried to compile too much for the atmega328.   Wondering why my screen was all screwed up.   Found I had a hashtag in the wrong spot. More compiling.   Now I have pretty colours everywhere, found out I have to save after doing the adjustment test, also found out why no capacitor was needed when doing the calibration.

These units are freaking amazing for AU$25.  The software and hardware inventors are up there with Ken Thompson and Steve Wozniak.
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 25, 2023, 12:58:49 am
I hope madires does not mind me doing this, but I added some new colours to my scheme.  I found the green to be too bright and tended to wash out the other colours on my screen as I have gone for pastel colours on a black background.  I also found the red too dark to see easily.

So I created

#define COLOR_PALE_GREEN    0x9fec    /* RGB 99FF66 */
#define COLOR_PALE_RED        0xfb6d    /* RGB FF6F6F */

I used this website to convert the hex colour I chose to the RGB565 form the tester uses http://www.rinkydinkelectronics.com/calc_rgb565.php (http://www.rinkydinkelectronics.com/calc_rgb565.php)

Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 25, 2023, 01:04:21 am
Here it is using the normal green and red.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on April 25, 2023, 01:08:47 pm
A little bit of fun: here's the last damaged capacitor I've tested. The kind of failure it developed fools K-firmware by looking a Xtal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on April 25, 2023, 02:21:04 pm
oitar, it is likely that ADC scaling is not working properly. Therefore, I propose several options for further action:
1. Remove capacitor C1 and repeat measurements without it. Does anything change?
2. Compile a new firmware, where the PA6 port will be assigned to measure the zener diodes. Apply external voltage(necessarily through a resistor divider) in the same way as you did before and check the response of this port.
3. You can try to upload firmware 1.13k.

1. Did not produce any noticeable change
2. Done, similar results to the original port. In fact that's what I did earlier, using the "Battery Votage" testing pin. They all have a problem with voltages below 1V(at the pin).
Did the following test by commenting off most lines between 156 and 163 in ADC.c:
/* get voltage of reference used */
  //if (Ref == ADC_REF_BANDGAP)      /* bandgap reference */
  //{
  //  U = Cfg.Bandgap;                 /* voltage of bandgap reference */
  //}
  //else                             /* Vcc as reference */
  //{
    U = Cfg.Vcc;                     /* voltage of Vcc */   
  //}

i.e. forcing VCC reference all the time.

Result: Both zener, and resistor measurements are now proportional, albeit with much bigger error. Also the "Adjustment" menu item keeps completing with Error.

Looks like I need much more digging, regarding bandgap calculation.

3. Haven't had a chance to check 1.13k yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on April 25, 2023, 02:28:18 pm
I have noticed a battery charge graphic at the bottom on some photos in this thread, looked in config.h but can't see the option to enable it  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on April 25, 2023, 03:30:55 pm
3. Haven't had a chance to check 1.13k yet.
Be sure to try this k-firmware and I will also suggest another option for m-firmware that you can easily check.
Turn on the #define ADC_LARGE_BUFFER_CAP setting, replace C1 with a 100nF capacitor and compile a new firmware with this setting.
Will there be any changes for the better? :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 25, 2023, 05:31:53 pm
I have noticed a battery charge graphic at the bottom on some photos in this thread, looked in config.h but can't see the option to enable it  :-//

That's a mod by a user, and is already on my to-do list.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 25, 2023, 05:46:00 pm
2. Done, similar results to the original port. In fact that's what I did earlier, using the "Battery Votage" testing pin. They all have a problem with voltages below 1V(at the pin).

When the voltage at the ADC pin is below the voltage of the internal band-gap reference the tester switches to the band-gap reference for better resolution and accuracy (both OSHW firmwares do this). Most likely there's a problem around the AREF pin. We use a small cap at the AREF pin to buffer the reference voltage (switched between Vcc and internal band-gap).
Title: Re: $20 LCR ESR Transistor checker project
Post by: vk3em on April 27, 2023, 11:32:46 pm

Yesterday I ordered another unit which just might contain the ATmega324. These things are cheap enough that I'll keep at it until I get the one I want!


Call me a sucker for punishment, but after recently failing with my purchase of the LCR-TC2 from this vendor (I wanted an ATmega324 but got the LGT8F328P), I've taken a gamble on the LCR-TC1 model from the same vendor. https://www.aliexpress.com/item/1005004717377243.html (https://www.aliexpress.com/item/1005004717377243.html)

What gives me hope?

Quote
LCR-T7 / LCR-TC1:color screen / M644 chip, two functions are the same! T7 is slightly faster! The TC1 screen is slightly larger and they are all powered by lithium batteries. In addition to measuring resistance, capacitance, inductance, diodes, MOS transistors, thyristors, it can also measure additional voltage regulators, infrared decoding (limited to for Hitachi format)
Self test with automatic calibration

In the LCR-TC2 description, it does not mention M644 (since it was delivered with LGT8F328P that makes sense) nor does it mention "Self test with automatic calibration" - this also makes sense as firmware for the LGT8F328P (in my case V3.1e) cannot fit the code for self-calibration. V3.1E firmware is also horrifically buggy, cannot reliability measure ESR, or Darlington transistors, etc. I will definitely be modifying my LCT-TC2 with LGT8F328P to the ATmega328P.

I can only presume (hope) M644 mentioned in the details of the LCR-TC1 description refers to ATMega644 and so far this is the only specific mention of M644 within an advertisement that I can find. Lets see when it arrives.

Luke

Nope - It's a fail, its not a M644. I guess you just cant trust AliExpress sellers (Note: I have a message response from the seller confirming prior to sale, the device contains an M644 chip!). Not sure if its a fake 328P. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 28, 2023, 03:00:45 am
I assume it is a fake as the chip has totally identical markings to the chip on my Fnirsi, right down to the DOM. There is no external crystal.  Also R1 and R4 (two of the important 470K and 680R resistors) are entering the chip at the same position as mine which is different to the photos of boards with real 328P chips that I have seen.

Here is a real 328p board.  https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg1016677/#msg1016677



Title: Re: $20 LCR ESR Transistor checker project
Post by: vk3em on April 28, 2023, 04:36:01 am
Thanks. The TC1 firmware identifies as "M-Tester" and the TC2 firmware identifies as "LCR-TC2 v3.1E".

"Short the three test sockets, press the multi-function button shortly, and the tester will automatically calibrate.
No other operations are required after disconnecting the short wiring according to the prompt during the calibration process."

Neither of the units seem to allow entry into a self-calibration mode, despite both providing the calibration shorting pins.

I'll do some side by side comparison to see how they perform, but it looks like I have no choice now but to build the GM-328 kit which came with a genuine Atmel MEGA 328P. I feel like I am walking in your footsteps :) ! In the future, I will try to convert the TC2 with its LGT8F328P to a MEGA328.

Its a pity because AliExpress SeeSensor has good ratings, and they obviously did sell genuine Atmel units, but not now, and not even if you ask them to confirm!

Luke
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on April 28, 2023, 07:26:50 am
I feel like I am walking in your footsteps :)

My footsteps seem to be like that monastery in the movie Where Eagles Dare.

You have a destination this monastery atop a cliff edged mountain.   Most sensible people take the nice safe cable car to the top.   I am often the fool you see scrambling up the cliff face, because I rushed in and never saw the cable car.  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: moghaddam on April 28, 2023, 09:48:09 pm
I also have a T7 (pictured attached, fake obviously). It was working fine, but since a few days ago, when I try to test anything, it randomly detects it as resistor or mostly inductor. I can't remember what was the last thing that I tested. I checked all the diodes (in circuit) and they all looks ok. I don't have a hot-air gun, so I have not tried to desolder caps to check them one by one. I just checked for short, and seems none of them are shorted.

My question may have already been answered, but at least I didn't manage to find it in the last couple of days that I'm reading through this thread (10 years old thread, really impressive ;) ). I was wondering maybe someone has already had this issue and could give me some hint to do further troubleshooting.

I'm not professional. Just a hobyist trying to learn electronics.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 29, 2023, 07:56:03 am
A common fault is a toasted SRV05-4.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on April 29, 2023, 11:19:47 am
My question may have already been answered, but at least I didn't manage to find it in the last couple of days that I'm reading through this thread (10 years old thread, really impressive ;) ). I was wondering maybe someone has already had this issue and could give me some hint to do further troubleshooting.
I would calibrate it first and then check again.
Have you done anything in the K-A-A range?
I have the same board and you should add a resistor anyway.
I have done that as well. (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4749236/#msg4749236)
You can find information about the problem in the forum.

See also: https://www.eevblog.com/forum/testgear/... (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4661896/#msg4661896)

And you most likely have an APT32F172K8T6 like I d (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4734371/#msg4734371)o, not an Atmega.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 29, 2023, 08:50:24 pm
I flashed a tester that I've had for a while with the 1.49m code and noticed a problem with too high hFE. It also doesn't stay consistent, changing from time to time. The following fixes it:

Code: [Select]
/* ************************************************************************
 *   workarounds for some testers
 * ************************************************************************ */


/*
 *  Disable hFE measurement with common collector circuit and Rl as
 *  base resistor.
 *  - problem:
 *    hFE values are way too high.
 *  - affected testers:
 *    Hiland M644 (under investigation, possibly poor PCB design)
 *  - uncomment to enable
 */

#define NO_HFE_C_RL

However, this is not some fancy M644. It's a GM328-3V from 2014. A very simple, straightforward design. It does have a converter from 3V to 5V. It has the same issue when powered from the ISP port, which bypasses the DC-DC converter completely. I removed the surge suppressor, too, thinking that it might be fried. Same problem. The tester is rock-solid stable with 1.13k firmware, but with 1.49m sometimes it shows 0pF between probes during self-test while other times is the usual 47-51pF. Not sure where to look for further problems there. Could the problem lie with the way 1.49m measures common collector current or is it definitely something with the hardware? I can't seem to find any hardware problems on the probe side of the chip. Connecting ISP header adds some capacitance, but that's the only thing I can see that's even remotely suspect. Any ideas welcome at this point because I'd like this particular unit to be running the latest M firmware, not K.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on April 30, 2023, 06:06:44 am
I can't seem to find any hardware problems on the probe side of the chip.
...
 Any ideas welcome at this point because I'd like this particular unit to be running the latest M firmware, not K.
Compare the Show Values with the photo to see if there are significant differences.
Title: Re: $20 LCR ESR Transistor checker project
Post by: moghaddam on April 30, 2023, 06:34:38 am
Thanks for your suggestions guys.

@madires I just checked the SRV05-4 forward voltages. Seems they're all in range (0.6-0.8V).

@Aldo22 It doesn't get calibrated (as shown in the picture posted in my original question) and only detects an inductor between 2-3 when I short 1-2-3 together. I know I had tested some diodes between K-A and changed diodes while the tester was on, so that could easily be the case. I will definitely add the 2K2 resistor to the board.

I read the answer you linked as well as your other similar answer with even more details at https://www.eevblog.com/forum/testgear/%2420-lcr-esr-transistor-checker-project/msg4692413/#msg4692413 (https://www.eevblog.com/forum/testgear/%2420-lcr-esr-transistor-checker-project/msg4692413/#msg4692413). There it says:

Quote
Unmodified (but working) LCR- units with APT32F172K8T6 MCU and the poorly designed U7 circuit will display 5-8V “zener voltage” with the 1k resistor connected to K-A. This is because DC-DC converter U7 actually does function as a constant current source (until it gets damaged).

When I put the 1K resistor, it detects it as an 8V Zener. Also I tried measuring a 3V Zener and it detects it correctly as 3.2V Zener and it doesn't get hot at all. So is it safe to assume the U7 current limiting is still working?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on April 30, 2023, 06:51:53 am
@moghaddam:
I can't tell you more as I soldered the resistor in before I had a problem.
I had the information from here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4661896/#msg4661896).

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on April 30, 2023, 11:14:35 am
The tester is rock-solid stable with 1.13k firmware, but with 1.49m sometimes it shows 0pF between probes during self-test while other times is the usual 47-51pF.

0 pF can happen when some values don't add up during the measurement. You could try ADC_LARGE_BUFFER_CAP to increase the delay for switching the ADC's reference voltage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on April 30, 2023, 10:57:08 pm
I can't seem to find any hardware problems on the probe side of the chip.
...
 Any ideas welcome at this point because I'd like this particular unit to be running the latest M firmware, not K.
Compare the Show Values with the photo to see if there are significant differences.

Please see the attached image. Looks reasonably close? Maybe I'm missing something there.

The tester is rock-solid stable with 1.13k firmware, but with 1.49m sometimes it shows 0pF between probes during self-test while other times is the usual 47-51pF.

0 pF can happen when some values don't add up during the measurement. You could try ADC_LARGE_BUFFER_CAP to increase the delay for switching the ADC's reference voltage.
Doesn't seem to change anything... I'll try to recompile again later, just in case. The actual cap measures around 1.1nF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 01, 2023, 02:40:57 am
The actual cap measures around 1.1nF.
Perform the marked items in order without turning off the tester. See if AComp = 0 changes, this value should not be =0.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on May 01, 2023, 04:16:01 am
I get the same numbers after that. Looking at the code, I think I what I see is that AComp = NV.CompOffset = Offset (please correct me if I'm wrong), but I don't really understand why 0 is bad. Offset looks like it can be positive, zero, or negative. So I'm still stuck.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 01, 2023, 06:25:42 am
So I'm still stuck.
Increase the capacitance on AREF to 10nF and repeat steps 1, 2, 3 of the previous message. From my experience AComp = 0 - incorrect tester calibration.
What does not suit you in 1.13k if it works correctly on your hardware? RLC measurements are an order of magnitude more accurate and my changes allow me to expand some measurements for Mega328.

I hope you read these calibration features - excerpt from autocalibration:

"The analog comparator voltage offset is automatically corrected when measuring capacitance (in normal test mode without auto-adjustment) if the capacitor is in the range of 100nF to 3.3μF. The offset for the built-in reference is defined in the same way. Before making auto -adjustment for the first time, measure the calibration capacitor with a capacitance value between 100nF and 3.3μF at least 3 times so that the tester can correct the offsets mentioned above.Usually, the first measurement will result in a lower capacitance value, the second one will result in a higher capacitance and the third one will be the most accurate. Both offset values will be displayed at the end of the procedure."
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 01, 2023, 09:24:51 am
The tester is rock-solid stable with 1.13k firmware, but with 1.49m sometimes it shows 0pF between probes during self-test while other times is the usual 47-51pF.

I also get 0pF on my MEGA4GSL with ATMega644 during the adjustment process, but this does not cause me any concern, since a subsequent similar procedure returns normal values ​​ 40-45pF. It is important that these values ​​are fixed in the profile that you save. I do not observe any problems with measurements due to this effect on firmware 1.49m, so you can safely work with the device.
Regarding Acomp=0 :
Usually, on devices with ATMega644, a high-quality calibration capacitance above 100nF (usually ceramics) is connected by default to one of the ATMega ports. Then the
#define HW_ADJUST_CAP
setting should be enabled in the config.h file, and the port to which calibration capacitance connected in file config_644.h :
#define TP_CAP           PA7       /* test pin for self-adjustment cap */
#define ADJUST_RH     PC5       /* Rh (470k) for fixed cap */
If there is no such hardware capacitor, then
Yuriy_K wrote above, it is necessary to measure the external calibration capacitance on the test contacts 3 times in a row to get the correct AComp value, which will be valid for the subsequent adjustment procedure.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Substance on May 06, 2023, 07:00:07 pm
A couple of months ago, I got interested in experimenting with a component tester. I bought an LCR-T4, but what I received was a clone which had a fake Atmel MCU, so I could not use the open-source software to modify and improve the tester. So, I started to create a tester from an Arduino Pro Mini compatible board with a genuine ATmega328P, together with the salvaged LCR-T4 LCD and new components.

First, I built the component tester that is compatible with LCR-T4 hardware. I tried the available v1.13k firmware binaries to see it run for the first time. Then I moved on to the v1.48m software distribution and created a makefile project for Microchip Studio for AVR and SAM devices.

Just to see what difference it would make (not a lot) I use hardware SPI for the LCD, and I had to dive into the v1.48m code to make all necessary changes to GPIO and ADC ports. I have made many (cosmetic) changes to the display output. I use a (small) subset of the available test functions to make it all fit into memory. To locate and to fix all the mistakes that I made in the process, I used serial output for code debugging and tracing.

Thanks to the available hardware and software documentation, and thanks to the numerous questions and answers from the users on this forum, I was able to get pretty good results. It may need further experimenting and tweaking. Next, I will look at the v1.49m code and merge it into my tester software.

@madires, @indman, Karl-Heinz Kübbeler (and many others): you do a very nice job making this project popular and accessible to many electronics enthusiasts!

I posted a few pictures at “Show us your $20 Transistor Tester enclosures and mods”.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 07, 2023, 11:26:24 am
Bohu has updated the Czech, German and English PDF documentation for 1.49m: https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on May 08, 2023, 06:26:29 am
2. Done, similar results to the original port. In fact that's what I did earlier, using the "Battery Votage" testing pin. They all have a problem with voltages below 1V(at the pin).

When the voltage at the ADC pin is below the voltage of the internal band-gap reference the tester switches to the band-gap reference for better resolution and accuracy (both OSHW firmwares do this). Most likely there's a problem around the AREF pin. We use a small cap at the AREF pin to buffer the reference voltage (switched between Vcc and internal band-gap).

Quick recap: T7 Plus, v1.1 with a mega324pa(allegedly original), with erroneous measurement of all ADC inputs below 1V, affecting zener and resistance measurement. As suggested by @madires and @indman, tried removing O/V protection, different firmwares(k and m), changing(or removing the AREF cap) with similar results.

Eventually I found a workaround- reading more about the internal bandgap reference on atmega chips, I found someone mentioning that switching from VCC reference to bandgap is a lot slower than the other way around. So I just changed the priority( inside ADC.c) from VCC to bandgap(changes shown in orange, original statement in green:


    /* auto-switch voltage reference for low readings */
    if (Counter == 4)                   /* 5 samples */
    {
      if ((uint16_t)Value >= 1024) //if ((uint16_t)Value < 1024)       /* < 1V (5V / 5 samples) */
      {
        if (Ref == ADC_REF_BANDGAP)//if (Ref != ADC_REF_BANDGAP)     /* bandgap ref not selected */
        {
          if (Cfg.AutoScale == 1)       /* autoscaling enabled */
          {
            Channel &= ~ADC_REF_MASK;     /* clear reference bits */
            Channel |= ADC_REF_VCC;//Channel |= ADC_REF_BANDGAP;   /* select bandgap reference */

            goto sample;                /* re-run sampling */
          }
        }
      }
    }

Now everything works fine. Thanks for all suggestions!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 08, 2023, 07:01:24 am
Eventually I found a workaround- reading more about the internal bandgap reference on atmega chips, I found someone mentioning that switching from VCC reference to bandgap is a lot slower than the other way around.
Now everything works fine.
Well, if your decision does not affect the results of other measurements. In any case, your controller turned out to be non-standard. This is not surprising, given the rise in price of the original ATMEL chips.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 08, 2023, 08:36:38 am
Eventually I found a workaround- reading more about the internal bandgap reference on atmega chips, I found someone mentioning that switching from VCC reference to bandgap is a lot slower than the other way around. So I just changed the priority( inside ADC.c) from VCC to bandgap(changes shown in orange, original statement in green:

That's one reason why there's an intentional delay when switching the reference voltage and also a dummy conversion. The ADC_LARGE_BUFFER_CAP option is meant for Arduinos with a 100nF cap at AREF and basically increases the delay by a factor of 100. But for investigating the strange behaviour of your tester's MCU you could increase the delay in the unmodified source until the measurements are fine. It would be interesting to know how large the delay needs to be, in case someone else runs into the same problem.

ReadU() in ADC.c:
Code: [Select]
    /* wait some time for voltage stabilization */
    #ifndef ADC_LARGE_BUFFER_CAP
      /* buffer cap: 1nF or none at all */
      wait100us();                   /* 100µs */
    #else
      /* buffer cap: 100nF */
      wait10ms();                    /* 10ms */
    #endif

For the waitX() functions available please see wait.S.

PS: Without setting the default ADC reference to the internal band-gap reference your changes disable voltage measurements with the band-gap reference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on May 08, 2023, 11:21:05 am

That's one reason why there's an intentional delay when switching the reference voltage and also a dummy conversion. The ADC_LARGE_BUFFER_CAP option is meant for Arduinos with a 100nF cap at AREF and basically increases the delay by a factor of 100. But for investigating the strange behaviour of your tester's MCU you could increase the delay in the unmodified source until the measurements are fine. It would be interesting to know how large the delay needs to be, in case someone else runs into the same problem.

ReadU() in ADC.c:
Code: [Select]
    /* wait some time for voltage stabilization */
    #ifndef ADC_LARGE_BUFFER_CAP
      /* buffer cap: 1nF or none at all */
      wait100us();                   /* 100µs */
    #else
      /* buffer cap: 100nF */
      wait10ms();                    /* 10ms */
    #endif


Well, that's the thing: I doesn't seem to change anything! I am using a 1nF cap(even removed it previously, suggested by @indman), so I'm working within this section:


Code: [Select]
    /* wait some time for voltage stabilization */
    #ifndef ADC_LARGE_BUFFER_CAP
      /* buffer cap: 1nF or none at all */
      wait100us();                   /* 100µs */


With default value of 100us, one measurement takes about 2sec, with wait1ms() it takes about 4sec, with wait10ms()- about 6sec, with wait 100ms()- 23sec, and with wait200ms() one measurement took 1min and 3 seconds to complete. For the sake of sanity I stopped it there. The reading is exactly the same.
It looks like the internal reference never gets down to it's intended value.


Quote
PS: Without setting the default ADC reference to the internal band-gap reference your changes disable voltage measurements with the band-gap reference.

But isn't the alteration I showed previously doing exactly that: starting the ADC sample with the internal band-gap by default, and only if it reads 1024- switch to the VCC reference? I did a zener test within the whole range: 1 to 24.5 V, and the readings are smack-on. Same with various resistors. I am quite convinced the precision hasn't suffered at all. Semis check fine, only checked few caps, but they look ok too.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 08, 2023, 02:39:22 pm
Well, that's the thing: I doesn't seem to change anything! I am using a 1nF cap(even removed it previously, suggested by @indman), so I'm working within this section:

Maybe it's not a delay (voltage stabilization) issue at all.

With default value of 100us, one measurement takes about 2sec, with wait1ms() it takes about 4sec, with wait10ms()- about 6sec, with wait 100ms()- 23sec, and with wait200ms() one measurement took 1min and 3 seconds to complete. For the sake of sanity I stopped it there. The reading is exactly the same.
It looks like the internal reference never gets down to it's intended value.

That's interesting! The delay should happen only once when switching from Vcc to band-gap. Increasing the delay would increase the time of the voltage measurement by the same delay. In the Zener check the voltage is measured several times. Hence the maximum delay should be: number of calls of ReadU() * delay. Have you tested that with the original code or your modfied ReadU()?

Quote
PS: Without setting the default ADC reference to the internal band-gap reference your changes disable voltage measurements with the band-gap reference.

But isn't the alteration I showed previously doing exactly that: starting the ADC sample with the internal band-gap by default, and only if it reads 1024- switch to the VCC reference? I did a zener test within the whole range: 1 to 24.5 V, and the readings are smack-on. Same with various resistors. I am quite convinced the precision hasn't suffered at all. Semis check fine, only checked few caps, but they look ok too.

To make your changes work you need also to change the default voltage reference, which is done here:
Code: [Select]
  /* prepare bitfield for register: start with AVcc as voltage reference */
  Channel &= ADC_CHAN_MASK;        /* filter reg bits for MUX channel */
  Channel |= ADC_REF_VCC;          /* add bits for voltage reference: AVcc */

So you start with Vcc and set Vcc again when Value >= 1024 (your mod), i.e. the band-gap reference isn't used at all. And since the measurements are fine with just the Vcc reference the actual problem is related to the band-gap reference. Let's try something else. Take the original ReadU() and change
Code: [Select]
      if ((uint16_t)Value < 1024)       /* < 1V (5V / 5 samples) */
to
Code: [Select]
      if ((uint16_t)Value < 900)
The idea is to check if the voltage of the band-gap reference might by a bit too low.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Swainster on May 09, 2023, 05:00:09 am
Just adding another data point on the LCR-TC2 to this thread

Old version vs new version, both bought from "Z industry store" on Aliex about 18 months apart.

Old version:
New version:

Overall, the new version is not as nice as the old version, but it mostly gets the job done. The transistor parameters seem to vary a lot between the 2 units, or some are missing altogether, however it seems to reliably identify the transistor type and pin out, so I think that it is still a useful addition to the electronics toolbox. That said, if you want to tinker with the workings, this is not the tool for you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on May 09, 2023, 05:40:00 am
That's interesting! The delay should happen only once when switching from Vcc to band-gap. Increasing the delay would increase the time of the voltage measurement by the same delay. In the Zener check the voltage is measured several times. Hence the maximum delay should be: number of calls of ReadU() * delay. Have you tested that with the original code or your modfied ReadU()?

With the original code. If I use the modified one, the reading is correct regardless of time.
When original code is used with various wait functions, it is definitely taking that long as mentioned.

To make your changes work you need also to change the default voltage reference, which is done here:
Code: [Select]
  /* prepare bitfield for register: start with AVcc as voltage reference */
  Channel &= ADC_CHAN_MASK;        /* filter reg bits for MUX channel */
  Channel |= ADC_REF_VCC;          /* add bits for voltage reference: AVcc */

You got me here :-[
As soon as I change the code you specify to: Channel |= ADC_REF_BANDGAP;, the wrong reading comes back- even with my modification still in place!


So you start with Vcc and set Vcc again when Value >= 1024 (your mod), i.e. the band-gap reference isn't used at all. And since the measurements are fine with just the Vcc reference the actual problem is related to the band-gap reference.

I'm afraid I cannot argue with that. For voltages between 3 and 24 V, the error is around 1.5%. Under 3 V it gets a lot worse: -3% at 2.0V, -5% at 1.5V, -9% at 1.0 V, and -18% at 0.5 V


Let's try something else. Take the original ReadU() and change
Code: [Select]
      if ((uint16_t)Value < 1024)       /* < 1V (5V / 5 samples) */
to
Code: [Select]
      if ((uint16_t)Value < 900)
The idea is to check if the voltage of the band-gap reference might by a bit too low.

Result:
Votage Input, V:     Reads as, V:
       10.5               10.66
       10.0               10.13
        9.5                 9.622
        9.0                 9.090
        8.5                 8.586
        8.0                 2.165
        7.5                 2.025
        7.0                 1.885
        6.5                 1.754
        6.0                 1.614
        5.5                 1.474
                  .........
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 09, 2023, 07:25:55 am
oitar,your board has a QFN44 form factor controller. Have you checked the reliability of the soldering of its contacts with a multimeter? The thought that there is a bad contact or not enough connection with GND does not leave me.There have been cases when soldering all the contacts of the processor fixed the problems. :-DMM
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on May 09, 2023, 09:08:02 am
oitar,your board has a QFN44 form factor controller. Have you checked the reliability of the soldering of its contacts with a multimeter? The thought that there is a bad contact or not enough connection with GND does not leave me.There have been cases when soldering all the contacts of the processor fixed the problems. :-DMM
Visually all solder points look ok. All GND pins of the chip read properly. I will try and re-solder all pins later.

Just for interest's sake, if the internal bandgap reference cannot be used(for whatever reason), can I swap it with the 2.5V external? This would give a better precision for voltages below ~2.5V. After a few attempts to modify the ADC.c code, I keep getting "timeout" errors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Sudya on May 09, 2023, 12:01:54 pm
Comparison of LCR-TC2 testers.
The firmware for the converted (LGT8F328) to ATMega328P is added to the folder with the sources.
(http://[attach=1])
(http://[attach=2])
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 09, 2023, 02:11:24 pm
Result:
Votage Input, V:     Reads as, V:
        8.5                 8.586
        8.0                 2.165

Seems to follow the lower threshold for switching to the band-gap reference. There are some measurements which use the band-gap reference directly. Do you also get strange values for ESR and inductance?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 09, 2023, 02:14:09 pm
Just for interest's sake, if the internal bandgap reference cannot be used(for whatever reason), can I swap it with the 2.5V external? This would give a better precision for voltages below ~2.5V. After a few attempts to modify the ADC.c code, I keep getting "timeout" errors.

As soon as you use an external voltage reference at AREF you can't use the internal ones anymore, i.e. neither Vcc nor band-gap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on May 09, 2023, 02:22:43 pm
Seems to follow the lower threshold for switching to the band-gap reference. There are some measurements which use the band-gap reference directly. Do you also get strange values for ESR and inductance?

Definitely when measuring resistance. Don't have proper samples(with known parameters) regarding ESR or inductance.
Title: Re: $20 LCR ESR Transistor checker project
Post by: oitar on May 09, 2023, 02:26:25 pm
As soon as you use an external voltage reference at AREF you can't use the internal ones anymore, i.e. neither Vcc nor band-gap.

I was hoping it's possible to just make the program use the voltage from the external source, but consider it the bandgap voltage, without re-wiring.
Sorry this is just my ignorance talking, I'm still learning the internals of an AVR.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on May 09, 2023, 10:12:49 pm
Just adding another data point on the LCR-TC2 to this thread. Old version vs new version, both bought from "Z industry store" on Aliex about 18 months apart.
   Old version:
      Generic case (with modification)
      f/w v2.3E
      PCB T7-PLUS v1
      Atmel marked 44 pin MCU
MCU very likely to be Atmel ATmega324.  Why do I think this is so?
   1) No Chinese MCU comes in 44-pin package (yet)
   2) 6-pin header near top edge of PC board is standard Atmel ISP programming interface. Chinese MCU don't use ISP. It is unique to Atmel

Some modification of existing -K or -M firmware may be necessary, but it certainly is feasible to replace the Chinese firmware because this MCU is actually mega324. Also possible to upgrade MCU to mega644 or mega1284.

Quote
New version:
Customized case based on original generic case
f/w v3.1E
PCB T7-PLUS v2.0
Unmarked 32 pin MCU
MCU likely to be LGT8F328P
Several people on this forum report successfully replacing LGT8F328P with Atmel ATmega328P. Hardware mod is simple because only a few pins have different functions. However existing -K or -M firmware needs modification for mega328P to work with this PC board. When time permits I plan to try this myself.   
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 10, 2023, 05:36:15 am
Using symbols_32x39_hf.h. For the correct display of contact numbers, you need to correct the line:
PIN_LEFT | PIN_BOTTOM, PIN_RIGHT | PIN_TOP, PIN_RIGHT | PIN_BOTTOM, /* UJT n-type */
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on May 12, 2023, 04:46:22 pm
I've just received a T7-H multi-function tester (V1.1 E) and it seems there is no way to perform the auto calibration, neither with the supplied 3 pin header nor by shorting the also supplied three DuPont cables with mini grabbers.

Is this the normal behaviour of this version? The calibration instructions supplied in the AliExpress page are for the T7... Is it different in this T7-H model?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 12, 2023, 06:20:50 pm
Very likely a tester with an alternative MCU.

Some hints on identifying the MCU:
- MCU in DIP is usually an genuine ATmega.
- APT32F172K8T6 has different power pins:
  - 32-LQFP/QFN: 18=Vss, 19=Vdd (ATmega328 32-TQFP: 5=Gnd, 4=Vcc)
- APT32F172K8T6 uses SWD port for ISP:
  - 5 pins: Vdd, Vcc, F_SDAT, F_SCLK, F_RST
- Testers with APT32F172K8T6 often lack a quartz crystal.
- LGT8F328 has slightly different pins:
  - QFP32L: 21=PE2/SWD (ATmega328 32-TQFP: 21=Gnd)
- LGT8F328 uses SWD port for ISP:
  - 5 pins: Gnd, Vcc, SWD, SWC, Reset
- Clone variants with an genuine ATmega are usually about EUR/US$ 5 more
  expensive than the variant with a different MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on May 13, 2023, 05:54:05 pm
MCU is unlabeled, 8 pins per side so no Atmel   |O

This one has a XTAL, albeit a very small one (X2) just by the pads for the bigger non existent X1.

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1782158;image)

Some more photos below, includig two showing the process of not performing the calibration as indicated in the instructions.


Comparing the readings with both a DER EE-5000 and a Peak Atlas DCA55, the values are all over the place  ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 13, 2023, 07:05:05 pm
5-pin ISP header (SWD), one pin connected to MCU's pin 21 -> LGT8F328
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on May 14, 2023, 08:03:05 am
Thanks a lot. I suppose there's nothing I can do with this tester other than asking AliExpress for a refund  ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 14, 2023, 08:36:41 am
I suppose there's nothing I can do with this tester other than asking AliExpress for a refund  ::)
Right! It is necessary to return such a low-quality product back to the seller and demand a refund of the money spent.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on May 15, 2023, 07:35:53 am
I'm afraid the return postage cost to China is greater than the cost of the item itself  ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on May 15, 2023, 04:39:15 pm
This chinese seller is really wicked  ;D

I sent him a message through the AliExpress messaging service explaining my concerns about the impossibility to perform a calibration with this tester. On next day the seller answered, in a very amicable way, to send him a video showing the problem. Everything OK so far so I did a couple of videos, one using the supplied 3 pin header and another shorting the also supplied three DuPont cables with mini grabbers. I uploaded both of them to my youtube channel.

So far so good... except for one little detail: AliExpress does not allow neither sending files through their messaging system nor even sending youtube links. As soon as the system detects a youtube link or even the word "youtube", the message is zapped and a menacing warning is produced:

Note: This message contains prohibited content and hasn't been sent. Any further messages of this nature may result in account restrictions.

Isn't it wicked?  ;D ;D ;D

Of course the seller is perfectly aware of this AliExpress behaviour and asks for a video just to make all things difficult  |O

I've sent a note to the seller explaining what happened (without using the evil "youtube" word). Let's see what the seller comes with now  ::)

Meanwhile, if you feel courious and want to take a look at those two aforementioned videos:

https://www.youtube.com/watch?v=BUVljg-bQZU (https://www.youtube.com/watch?v=BUVljg-bQZU)

https://www.youtube.com/watch?v=jnuHhBpvZ4k (https://www.youtube.com/watch?v=jnuHhBpvZ4k)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on May 15, 2023, 05:21:31 pm
Ah, by the way, anyone knows what is hFEr?


(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1784063;image)


Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 15, 2023, 05:26:37 pm
Ah, by the way, anyone knows what is hFEr?
hFEr=REVERSE_HFE
"All transistors have inverse Hfe, since you can always swap the collector and emitter. This is equivalent (but not strictly identical - Hfe is a large signal, BF is a small signal hybrid signal) to the SPICE BR parameter, just as BF is equivalent to Hfe."

Link: https://www.physicsforums.com/threads/what-is-reverse-hfe.305553/ (https://www.physicsforums.com/threads/what-is-reverse-hfe.305553/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on May 15, 2023, 06:28:03 pm
Thanks, mate!    :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: 4thDoctorWhoFan on May 15, 2023, 08:26:05 pm
I did not realize these testers had a selftest/cal mode. lol
I tried it on my T7H and it worked.  I guess I have older firmware as mine says v1.1 (No E after the 1.1 like yours in the pictures)

Perhaps it's just a firmware issue and not a hardware problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on May 15, 2023, 09:16:42 pm
The self-adjustment feature is simply missing in the modified firmware for that specific alternative MCU. Either it's the lack of flash memory or the manufacturer is unable to adapt the self-adjustment to the other MCU. Because ATmegas are quite expensive at the moment some clone manufacturers switched to other MCU types. And those testers are a disaster, mostly thanks to a poorly ported firmware.

BTW, TC-1 and similar clones run a modified k-firmware (fancy graphics, less features).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on May 16, 2023, 06:05:33 am
Then which is the best option today?  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 16, 2023, 06:23:16 am
Then which is the best option today?  :-//
M328Kit+TFT RGB(GM328A) ATMega328 Dip form factor. It is easy to make an adapter for this clone for ATMega644.
This is the best option for today, so as not to get a fake and wasted money, nerves and time! ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on May 16, 2023, 07:53:07 am
Then which is the best option today?  :-//
M328Kit+TFT RGB(GM328A) ATMega328 Dip form factor. It is easy to make an adapter for this clone for ATMega644.
This is the best option for today, so as not to get a fake and wasted money, nerves and time! ;)
Well, that's the one I have (the T7-H was purchased for a friend).

Mine is the M328Kit+TFT(AY-AT) but has a buggy SW that prints trash instead of some symbols. Don't really know how to update the SW. I must find a "guide for dummies" somewhere  ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on May 16, 2023, 09:47:41 am
Bohu has updated the Czech, German and English PDF documentation for 1.49m: https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation

... Look to the Documentation of madires.

Regards Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on May 16, 2023, 09:52:58 am
Then which is the best option today?  :-//
M328Kit+TFT RGB(GM328A) ATMega328 Dip form factor. It is easy to make an adapter for this clone for ATMega644.
This is the best option for today, so as not to get a fake and wasted money, nerves and time! ;)
Don't you think the Hiland M644 is also a good option?

A bit pricey now (nearly $40 at Banggood (https://www.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html) when, f I remember well, I got it under $20) but already M644 and complete with prescaler and voltage booster for zener testing. AFAIK, no fake CPUs in this one also.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on May 16, 2023, 10:06:09 am
Don't you think the Hiland M644 is also a good option?
Yes, this is also a good option, but now it has almost disappeared from sales and sellers' offers. In addition, it is equipped with a monochrome display, which slightly reduces its merits. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on May 16, 2023, 11:46:14 am
True, it's hard to find now, even Banggood (https://www.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html) is out of stock now (the ad says "Restocking. Expected to ship before Jun 15").

The only place that seems to have stock is  here at taobao (https://item.taobao.com/item.htm?spm=a312a.7700824.w4004-22682728178.39.62fe70c4XLipQb&id=675714677875), (and very good price, $17 + shipping, I suppose). Unfortunately, I don't know how to buy at Taobao or if they would ship outside China. This seller (https://shop35395693.world.taobao.com/) also has two other versions of the tester, and he seems to be the manufacturer of the kits; maybe he would be interested in making a 644 version with a color screen if somebody tells him  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on May 17, 2023, 01:47:43 pm
hi,
i've often bought from taobao, but unfortunately that only works through a so-called sales agent and causes additional costs such as overseas shipping and agent fee. and depending on the country, there may be additional customs duties because bhiner does not collect them immediately, e.g. aliexpress or ebay.
best regards

https://www.bhiner.com/ (https://www.bhiner.com/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on May 18, 2023, 02:57:28 pm
Ah, by the way, anyone knows what is hFEr?
hFEr=REVERSE_HFE
"All transistors have inverse Hfe, since you can always swap the collector and emitter. This is equivalent (but not strictly identical - Hfe is a large signal, BF is a small signal hybrid signal) to the SPICE BR parameter, just as BF is equivalent to Hfe."

Link: https://www.physicsforums.com/threads/what-is-reverse-hfe.305553/ (https://www.physicsforums.com/threads/what-is-reverse-hfe.305553/)
There is a class of small-signal BJT transistors which have “reverse Hfe” of similar magnitude to their forward Hfe. In addition their E-B reverse breakdown voltage is similar to the E-C breakdown voltage, typically ~25V.

These devices are marketed for “audio muting” applications at analog line-level signal levels ( <5V RMS ). The E and C pins are interchangeable. A typical application circuit sends the output from an opamp through a ~1k ohm series resistor followed by the audio muting transistor operating as a controllable shunt to ground. Application of base current to the audio muting transistor provides >80dB of audio muting. The transistor is an open circuit when the base is reverse-biased. The reverse bias voltage is usually >10V. This is large enough to prevent clipping of the audio signal.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on May 18, 2023, 04:54:02 pm
True, it's hard to find now

If you add up the sales agent fee, shipping costs and taxes/duties, it's just as expensive as this one and he can deliver immediately :-+

https://www.elecbee.com/en-29467-Original-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-Frequency-Counter-PWM-Wave-Generator-Online-ESR (https://www.elecbee.com/en-29467-Original-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-Frequency-Counter-PWM-Wave-Generator-Online-ESR)

Economic Shipping $5.00 About 5-15 Days to EU


Title: Re: $20 LCR ESR Transistor checker project
Post by: Pukker on May 22, 2023, 07:30:12 am
How frustrating can the Chinese be?
Nice project by Markus Frejek, Karl-Heinz Kübbeler and all others,
the Chinese must be thinking "Aha, nice money making project"
They started making and selling useful versions.
Now they are back in their core business, MAKING FAKE. AARCHHHH |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 23, 2023, 11:51:28 am
For k-firmware using ILI9341 developed a new font for outputting 8 lines. In the original version, 7 lines were displayed. There are a lot of changes, now I'm checking all the output options on the screen. Who is interested write.

An example of a full font and an example of measurement in the photo...
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on May 23, 2023, 06:28:12 pm
Just adding another data point on the LCR-TC2 to this thread. Old vs new version, both from "Z industry store" on Aliex 18 months apart. New: Custom case based on original generic case, f/w v3.1E, PCB T7-PLUS v2.0, unmarked 32 pin MCU
This MCU is likely to be LGT8F328P.  Other EEVblog posts report successfully replacing LGT8F328P with Atmel ATmega328P. The hardware mod is simple: Only a few pins have different functions. However, existing -K or -M firmware needs modification for mega328P to work with this PC board. When time permits I plan to try this myself.
This week I received 5x LGT8F328P boards which are (somewhat similar) to the popular (Arduino) "pro-mini" board. A "boards" definition package is available for using these LGT8F328P boards with the Arduino IDE. I intend to experiment with Transistor Tester software which has been ported to the LGT8F328P. But first I will get familiar with the LGT8F328P by comparing its performance to Atmega-based Arduino boards (which I've been using for >10 years).

To me the LGT8F328P has an interesting feature set: Its I/O pins have full 5V capability, and a "handful" of them (not all) are rated at 80mA. This may be useful for the Transistor Tester because larger I/O output current corresponds to lower internal resistance/impedance. This might improve accuracy for measurements of small resistance and for capacitor ESR. The LGT8F328P would get even more attention from me if the manufacturer introduced a version with 64k flash.  
Title: Re: $20 LCR ESR Transistor checker project
Post by: vk3em on May 24, 2023, 07:04:17 am
I am thinking about building my own LCR tester based on one of the open hardware designs. I am looking for something M644 based and prefer SMT components rather than through hole.
I will get the PCB made professionally so plated holes and vias is not an issue. I have found the Mega 4GSL but are there others I have missed? Happy to consider all options.

Cheers
Luke
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 27, 2023, 07:15:49 am
I show my version of the conversion of Hiland M644 to ILI9341. Changes in the scheme and pictures of modernization and measurements. So far, only what I have debugged.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 27, 2023, 07:18:27 am
Measurement examples did not fit due to limitations.

P.S. Made a new body. Once placed in the housing, it must be recalibrated due to the effect of the dielectric between the three lower redundant inputs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on May 30, 2023, 01:50:13 pm
hi yuriy,
don't understand the green connection and the series resistor for BL certainly ohm and not kohm!?
do you also have the firmware as hex and eep and would you kindly provide them?
I am currently working on an (improved) pcb copy and will take the changes into this immediately.
I also found this booster mod (for the zener test voltage) on github
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 30, 2023, 03:32:17 pm
don't understand the green connection and the series resistor for BL certainly ohm and not kohm!?
In my board there was 2-3 ohms between AGND and GND - a defect in the board. Eliminated with a short jumper.
New displays require resistors of the indicated kOhm ratings.
I just finished fixing the firmware yesterday, but I haven't fully checked it yet. Here are the fixes for today.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on May 30, 2023, 03:57:33 pm
Quote from: Yuriy_K
New displays require resistors of the indicated kOhm ratings
yes, the 5x 10k in the data lines are fine, but 68-100k in the line for the backlight?
there won't be much light! 30\$\Omega\$ are right ! display needs 3,2V 60mA for backlight.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on May 30, 2023, 05:07:54 pm
there won't be much light! 68-100\$\Omega\$ are right ! display needs 3,2V 20mA for backlight.
I indicated the real value in my circuit, if you want to burn the display, put whatever you see fit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on June 01, 2023, 07:32:41 am
hello,
on the board a 1k resistor R6 is already inserted in the base line of the transistor,
according to the data sheet pin LED can be connected directly to 3V3 for maximum backlight,
nothing will burn there! where can you get the information for the 68-100K resistor ?
regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 01, 2023, 07:47:51 am
snapper,
There is a factory datasheet for each type of display, which indicates how to connect the power and backlight circuits.
This datasheet and be guided by the connection. This is a childish question for a person who understands electronics.
It's just that displays of the same diagonal exist have slightly different backlight control - in one it is controlled directly through a limiting resistor, in the other by a certain voltage level to the base of the control transistor or PWM. :)
Title: Transistortester AVR AY-AT Adapter für ATMEGA644
Post by: snapper on June 02, 2023, 01:43:42 pm
hey,
this is a project by Boleslaw J. and my idea to develop a circuit board for it.
the project has now been tested and completed and the pcbs are available.
see https://www.mikrocontroller.net/topic/transistortester-avr?page=31#7381379 (https://www.mikrocontroller.net/topic/transistortester-avr?page=31#7381379)
and ongoing.
if interested on adapter PCB please send me PM
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 02, 2023, 01:57:51 pm
The ATmega644 adapter for the AY-AT clone is accompanied by a modified m-firmware with added graphical output of the IR signal in the IR receiver/decoder function. That mod is done by Boleslaw J. (boleslaw_43): https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware

Edit:
And the PCB layout of Boleslaw's ATmega644 adapter for the AY-AT clone (format: Sprint Layout 6): https://github.com/madires/Transistortester-Warehouse/tree/master/Hardware
Title: Re: $20 LCR ESR Transistor checker project
Post by: .RC. on June 03, 2023, 01:16:00 am
Is the 644 Upgrade to the AY/AT board via the daughter board only for the increased memory. I ask as I cannot see where you can easily use the extra pins available on the 644. I know all the pins on the 328 are used, so I thought you were restricted to what you can switch on in the firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on June 03, 2023, 02:47:57 am
The control of the display has been changed to hardware SPI and there is a new generator output GEN (OC1B on pin 13) on the daughter board with a frequency output of 2 MHz.
the rest e.g. modified m-firmware with added graphical output of the IR signal, read in mikrocontroller forum posts
https://www.mikrocontroller.net/topic/transistortester-avr?page=31#7401381 (https://www.mikrocontroller.net/topic/transistortester-avr?page=31#7401381)
search for the contributions of boleslaw j. (all in english)
the new GEN connection of the adapter can be wired to the terminal block of the old one, as this is no longer required,
the old connection / conductor track must be severed for this purpose!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Sudya on June 08, 2023, 07:50:34 am
Comparison of LCR-TC2 testers and their firmware.
EFUSE 0xF7 (Solution for switching off the tester when measuring capacitors).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Sudya on June 08, 2023, 07:56:43 am
Markus Reschke firmware 1.49m.
LCR-TC2(T7-Plus V2.0) converted from LGT8F328 to Atmega328p, put a jumper where LGT8F328 programmer connection, 18 leg to plus, (21 can not touch, just an old photo).
I set the fuse, it does not turn off on capacitor test. Slightly amended the code, on my copy of the tester between 1-2, 1-3 and 2-3 shows very close values. It used to overestimate the capacitance and esr between 1-3.
EFUSE 0xF7 (Solution for switching off the tester when measuring capacitors).
Download LCR-TC2(T7-Plus V2.0 (Atmega328) firmware. (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=1801457)
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 11:08:08 am
Hi,

I have a GM328A that has been languishing in a drawer awaiting repair for about two years that I have only just had time to get round to this week.  It initially worked fine but began to fail now and again by displaying a white screen momentarily as the encoder was pressed to start it up.  Now that's all it does when the encoder is pressed.  I reflowed the solder on the TFT screen's pins as well as the socket into which it plugs on the main board, which made no difference.  I also flexed and tapped just about everywhere to see if I could get it to come to life again, but no joy.  However, during very warm weather (over 30°C) last year I thought I would try it and it worked, once, then died again.  Whether this was coincidence or the increased ambient room temperature I am not sure.  I have just taken it apart now and checked all the resistances of the resistors and they all measure according to their PCB stated values.  Looking at the soldering of the various components under a fairly high strength magnifying eyepiece I see nothing suspect.  I know this is not unquestionable proof that there are no dry joints, but I would like to avoid a full reflow of the board if I can.  I removed the ATMega328P to see what happens when the chip is removed, but the fault is the same.  Would this happen anyway as the chip is not installed, or is it a clue to the stage the fault must exist in?

So that I can understand the stage at which the fault is likely to be, is anyone able to briefly describe the procedure the GM328A follows as it powers up and engages the  ATMega328?

Thanks!

Ad
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 09, 2023, 11:18:38 am
UltimateX,
First of all, you need to arm yourself with a circuit diagram for your clone and also with a multimeter, with which you should measure the +5V supply voltage when you press the Test button, which should be on the 7th pin of the processor. Next, make sure that the LED on the upper left side of the board lights up and stays on when you press the Test button.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 11:50:30 am
Hi Indman,

Thank you for the schematic and advice.  I will test for the 5V shortly and feed back, but I know from previous testing that the LED does not light when the encoder is pressed.  I tested the LED yesterday with my DMM on the diode setting and it lights, so I know the LED itself is functioning normally.

Thanks!

Ad
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 02:59:42 pm
Hi,

Yes, I can confirm that +5V is reaching pin 7 of the µC when the encoder is depressed.

I then went looking for why the LED fails to light.  Looking at the schematic, the failure would imply that the base of Q1 (9014) was not being turned on.  I tested the base of T1 while depressing the encoder and I got 5V on the µC side of R8 (27k), but not on the Q1 side.  So, I retested R8 in circuit and it measures 27k. Hmm....  So do you think T1 is duff?

Thanks! 
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 09, 2023, 03:08:02 pm
Check the functionality of C2 (it can be removed for a while) and transistor Q1.
Is the processor now inserted in the DIP panel?
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 03:12:25 pm
Yep, I didn't take the µC out.  It's been there during testing.

Let me remove C1 and see what happens.  I'll be back.

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 03:30:00 pm
I removed C1 and no change.  I took out T1 and tested it on my older M328 tester and it tests fine as an NPN transistor.  ???
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 09, 2023, 03:35:22 pm
I wrote about the capacitor C2, which is installed in the base of transistor Q1. Do you have it marked as C1?
What is the voltage at the base of transistor Q1 now, if the Test button is pressed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 03:51:01 pm
Hi,  Sorry, I thought I read C1 on your original reply.  I need to remove C2 instead and test.

I measured the wrong 27k resistor - R15 instead of R8 - as they are beside each other and not sequentially marked.  I tested the voltage both sides of R8 and its 0V for both, so nothing is coming out of pin 12 (PD6) when the encoder is pressed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 04:02:47 pm
Removed C2 and no change.  Do you think it looks like I have a faulty ATMega328 or corrupt firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 09, 2023, 04:05:00 pm
When repairing, you need to be especially careful, otherwise you risk losing the device forever.
Solder a jumper between the emitter-collector of Q1. The LED should be on when the encoder button is pressed.
What will be on the display in this case? The absence of voltage on pin 12 indicates that the software did not start normally.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 04:19:57 pm
Thanks Indman.  The LED comes on anyway as power is direct to T1, not via the encoder.

What happens is the LED and screen both come on when the emitter and collector are shorted, but, again, a blank white screen.  When I press the encoder the LED goes off but the screen stays on with just the white screen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 09, 2023, 04:22:43 pm
You need to check ATMega328 with a programmer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 04:28:37 pm
I have the one in the attached photo.  Are there instructions somewhere on how to check, test, dump the chip contents, etc?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 09, 2023, 04:32:02 pm
I have the one in the attached photo.  Are there instructions somewhere on how to check, test, dump the chip contents, etc?
In your photo, this is not a programmer, but an attachment to the USBASP programmer. Do you have USBASP?
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 04:40:46 pm
I don't have USBASP but I thought I could upload new firmware to ATMega chips with the USB attachment.  Can you suggest what I should I get to check and test my ATMega328?  Thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on June 09, 2023, 04:51:56 pm
https://www.ebay.co.uk/itm/255552888808 (https://www.ebay.co.uk/itm/255552888808)

the atm328 of the chinese clones are mostly read protected, so you can only load a new firmware!
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 05:31:37 pm
Thanks snapper.  So I buy the"USBasp ISP Programmer including cable" in your link and connect it to the chip writer device I showed in my photo previously, right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on June 09, 2023, 05:44:47 pm
Yes is correct, but you still need software, I use this

https://extremeelectronics.co.in/avr-tutorials/gui-software-for-usbasp-based-usb-avr-programmers/ (https://extremeelectronics.co.in/avr-tutorials/gui-software-for-usbasp-based-usb-avr-programmers/)

http://digitalwizard.co.in/download.php?file_name=extreme_burner_avr_v1.4.3_setup.exe (http://digitalwizard.co.in/download.php?file_name=extreme_burner_avr_v1.4.3_setup.exe)

close VTarget jumper on the USBASP board and the usb connection to the board with the 28pin socket is then not needed.

https://www.fischl.de/usbasp/ (https://www.fischl.de/usbasp/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 09, 2023, 06:24:02 pm
Thanks very much, snapper.  I will take a look.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: danielferran on June 10, 2023, 10:31:28 pm
hi, i am trying to put the firmware one new 328P, cause I burned the original one of the device, but there is an error on AVRDudess.... could anyone help me? i am a dumb in burning HEX files... sorry for my english to... i am using arduino isp..


Using the AVRDUDE Software it shows this error...on the att
  :-[
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on June 11, 2023, 08:52:37 pm
hi, i am trying to put the firmware one new 328P, cause I burned the original one of the device, but there is an error on AVRDudess....

Using the AVRDUDE Software it shows this error...on the att
  :-[
Looks like your 'new' 328P is faulty. Where did you get it?
Are you sure your programmer is connected correctly?
Title: Re: $20 LCR ESR Transistor checker project
Post by: danielferran on June 12, 2023, 02:32:10 pm
I have checked the connections, the 338p IS New, from Aliexpress... I don't know, we have to burn a bootloader ir something like this on the New chip?
i have other 328p, but I don't know, os ter something measing?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 12, 2023, 02:35:28 pm
danielferran AVRDude tells you that the ATMega328 is not detected. If you have other ATMega328 check them also by connecting to the programmer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on June 12, 2023, 04:18:03 pm
@danielferran
Please take high-resolution photos of your bside tester with the new ATM328P and how you connected it to the programmer and upload them here.
Title: Re: $20 LCR ESR Transistor checker project
Post by: danielferran on June 18, 2023, 07:38:52 pm
I have tried 2 arduinos as ISP, and tried to burn a New pro mini, but the same...
Title: Re: $20 LCR ESR Transistor checker project
Post by: danielferran on June 18, 2023, 07:50:00 pm
Here friend... I have tried to upload in a pro mini board but the same happens.... with other Arduino I could upload an hex file normaly....
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on June 18, 2023, 09:54:28 pm
hi Daniel
you wired wrong, read here -->

https://docs.arduino.cc/built-in-examples/arduino-isp/ArduinoISP

where do the settings for the fuse bits come from?
I flashed my bside with low=CE, high=DF and Ext.=FF and it worked!

a new version AVRDUDESS is available here -->
https://github.com/ZakKemble/AVRDUDESS/releases/download/v2.14/AVRDUDESS-2.14-setup.exe

Title: Re: $20 LCR ESR Transistor checker project
Post by: danielferran on June 19, 2023, 08:46:50 pm
Thank you, I Will try! i read about the wiring and in the sites they say this.... After I workout I Will try
Title: Re: $20 LCR ESR Transistor checker project
Post by: danielferran on June 19, 2023, 11:04:36 pm
It is alive! Man, you help a lot! thank you!
I searched many sites on the web, tried many different softwares and configurations!
Is ther someone with the entire code? I would like to translate in portuguese...
The interface is different, but it seams that is working!

Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on June 20, 2023, 04:32:04 am
"I would like to translate in portuguese..."

https://github.com/Mikrocontroller-net/transistortester/

https://github.com/Mikrocontroller-net/transistortester/tree/master/Software/trunk
Title: Re: $20 LCR ESR Transistor checker project
Post by: Asko B. on June 22, 2023, 09:12:45 am
Hello
Sry, translatet by DEEPL

In the picture of user UltimateX, the board is labelled HW-849A.
The one I bought recently is labelled GM328A, but it is identical.
In principle, both versions are SMD versions of the AY-AT.

But what strikes me about the picture:
 https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg4901579/#msg4901579
the capacitor "102" is missing at pin21 AREF.
Mechanically broken off or cold solder joint and fell off.

Greetings Asko
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 22, 2023, 09:19:47 am
But what strikes me about the picture:
 https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg4901579/#msg4901579
the capacitor "102" is missing at pin21 AREF.
Mechanically broken off or cold solder joint and fell off.
For modern firmware, this capacitor does not really matter, so it is not necessary to install it. You can read more about this in the manual from Karl-Heinz. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Asko B. on June 22, 2023, 11:14:50 am
Hello indman,

I must have missed the part about the capacitor at AREF.

I also noticed that the voltage reference is no longer needed when using
MCP1702/1703 is no longer needed at all.
This was not the case in the days of K-Software < 1.xx.

At some point, the diode in the switch-on control also seems to be
disappeared (without a sound).

I wrote that the choke in the power supply of the AVR, which I had intended
power supply of the AVR is not needed, Karl-Heinz wrote to me a long
a long time ago.

Great! Three components less!
K.I.S.S.      :)

Greetings Asko

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 22, 2023, 01:22:13 pm
The external 2.5V voltage reference makes only sense if the tester has a crappy 5V regulator. If you can get an MCP1702/1703 (0.4% voltage tolerance) go for it. The inductor in the Vcc rail is meant primarily as a filter for AVcc.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MathWizard on June 22, 2023, 09:54:38 pm
I have 1 of these generic ebay testers, from ~2017, IDK what chip, but with the big 2*4" screen or so.

But recently I took off a sot23 SMD part, marked as NAN, and the tester said it was a JFET, but with no negative rail, it said Vgsoff was like 63.2V and Idss was 2.8mA or something like that.

This thing seemed to check mosfets ok. Has anyone ever had a MOSFET read as a JFET on 1 of these testers?

Going by the pinot the tester said, I checked it with a dual PSU and it seemed to turn on at about -1.8Vgs, as I headed towards Vgs=0V, and at Vgs=0, it seemed to have an Idss of 10-20mA, with a 1k res. on the drain to Vdd, but with Vdd going past 23V, I seemed to have zapped it somehow.
more details below
https://www.eevblog.com/forum/repair/what-is-this-jfet-and-whats-its-purpose/msg4913053/#msg4913053 (https://www.eevblog.com/forum/repair/what-is-this-jfet-and-whats-its-purpose/msg4913053/#msg4913053)


But I'm not sure if it was really a JFET, although if the tester pinout was correct, it never had any gate current, until I fired it a bit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on June 23, 2023, 08:24:51 am
Does your tester run one of two original OSHW firmwares or a modified one? Older firmware versions have an issue with confusing Germanium BJTs (leaky) with JFETs.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on June 23, 2023, 11:28:11 am
But I'm not sure if it was really a JFET, although if the tester pinout was correct, it never had any gate current.
To help you, we have to see your measurements on the display. For example, such as in the picture.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on June 23, 2023, 04:47:23 pm
Hi Yuriy,

I installed your ST7735_RGB_en16MHz software on my AY-AT today. Everything works fine so far - but it doesn't recognize any crystals  :-// ?

Greeting Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on June 23, 2023, 05:14:42 pm
Hi Horst,

The Mega328 does not have enough memory for such measurements. Mega644 or higher required.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on June 24, 2023, 01:28:42 pm
Hello Yuriy,

You are absolutely right, if you want to use all the functions of the KH 1.13 version, the memory of the Atmega328 is not enough.

So for this test I turned off the (CFLAGS += -DWITH_MENU) function and was able to use the quartz test function.

Greeting Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 02:58:06 pm
Hi,

Further to my previous post, I bought the USBasp ISP programmer and connected it to the dev board and my laptop (see photo).  I've launched Zadig and followed the https://www.instructables.com/USBASP-Installation-in-Windows-10/ (https://www.instructables.com/USBASP-Installation-in-Windows-10/) instructions; however, the left Driver box shows "(NONE)", not "libusb0 (v1.2.6.0) as shown on the instructables image.  I selected libusb-win32 on the right Driver box and the installation successfully completed, according to the Zadig log.  I expected the driver (NONE) in Zadig to be replaced by the installed driver, but it still shows "(NONE)".  Furthermore, Windows 10 still shows "USBasp Driver is unavailable" under Windows Settings > Bluetooth and other devices.  Device Manager also shows "The drivers for this device are not installed. (Code 28)".

Any clues as to where I am going wrong?  :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 04:10:23 pm
Sorted.  Didn't realise there are two installations (which the Instructable doesn't describe): one for the Windows driver and one for the WCID.  Getting the correct Zadig interface now.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on June 24, 2023, 06:21:23 pm
don't forget the V-Target jumper!
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 06:27:29 pm
Hi,

I have my USBasp connected and reading and writing with Extreme Burner (EB).  Referring back to post #8626, I installed the ATMega328P from the faulty GM328A in the chip reader and read the chip GM328A firmware into EB, then successfully wrote it out to a new ATMega328P.  I tried the new ATMega328P in my GM328A, but I still get the white screen a referred to in my post .  Could this be due to corruption of the GM32A firmware?  Is there a way of verifying the firmware or is re-flashing the latest GM328A firmware the quickest option?

Thanks   
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on June 24, 2023, 06:35:02 pm
please show what the SW reads!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 24, 2023, 06:36:25 pm
UltimateX,you need to fill in the controller with known working firmware and not the firmware you read from the ATMega328.
For example, this one I have attached below
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 06:42:55 pm
Thanks Snapper.

My USBasp didn't come with one, but I had a spare.  The model of my USBasp looks different to your image and silkscreen printing on mine does not have "5V" and "3.3V" on JP1.  Mine has the same pin layout but with JP21 in place of JP1 and JP1 where JP2 is on your image.  I assumed it was the same and installed my jumper on the 3.3V pins.  Is this correct for ATMega328P?
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 06:52:40 pm
If there is a particular piece of info you would like me to screen copy please let me know.  I have attached the .hex and .eep files (pls rename) in the meantime in case they are useful.

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 24, 2023, 07:04:27 pm
Mine has the same pin layout but with JP21 in place of JP1 and JP1 where JP2 is on your image.  I assumed it was the same and installed my jumper on the 3.3V pins.  Is this correct for ATMega328P?
On your USBASP the jumper must be set to +5V because the ATMega328 needs to be supplied with +5V programming voltage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 07:12:10 pm
Thanks indman.  So it is the reverse of the other USBasp's pins, which is fortunate as I installed the jumper on the 5V pins.  :)

I erased my new ATMega328P and installed your 1.12k firmware.  I then tried the new 328P in my GM328A, but there is no change - still I get the white screen.   Something tells me I still have a hardware fault somewhere, unless I have not flashed the firmware to the new ATMega328P properly or it is incompatible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on June 24, 2023, 07:16:16 pm
how are the fuse bits set?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 24, 2023, 07:17:48 pm
UltimateX,connect any working LED to the test pins, e.g. 1-3. After you press the Test button will this LED light up for a short time?
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 07:27:17 pm
Thanks Snapper.  Attached is the fuse bits tab.

Is there a way of loading/saving the fuse bits settings from/to a cfg file in XB?
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 07:33:07 pm
Thanks indman.  The test LED installed in the component DIP socket does not light or flicker at all.  All that happens is the white screen appears while the encoder is pressed down, then disappears as soon as the encoder is let go.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 24, 2023, 07:46:26 pm
Set the fuses as I showed in the screenshot.Then erase the crystal and write the firmware files again.Then by re-reading make sure that the fuses are written correctly as I showed you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 08:03:14 pm
I set the fuse bits as you showed, wrote out the full firmware, then read it back into the EB but it reverts to the fuse bits I showed in my previous image (attached).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 24, 2023, 08:14:59 pm
UltimateX,it means that the program cannot write the set values correctly. But even with the fuses as you showed, the program should start normally and the display should show a picture.
Can you create a short video of how your tester turns on? Sometimes it helps to understand and identify the problem more quickly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 08:20:40 pm
Okay, I got the fuse bits to set what you showed but when I read it back it keeps changing the second fuse bit (High Fuse) from D9 to DF??   I tried it in the GM328A but it still does nothing useful.

I will make a short video of the fault.

Thanks indman.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 24, 2023, 09:00:26 pm
3gp file made of fault.  Please remove ".txt" to play file.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 25, 2023, 03:38:09 am
Looks like the program doesn't run at all. Maybe try changing the fuses to use internal clock to check this. Or replace the quartz (I'd recommend going for 16 MHz).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 25, 2023, 10:35:56 am
3gp file made of fault.
There is no correct controller start. In order to go further in the troubleshooting process you must first make sure that the firmware and fuses are correctly written and read into the ATMega328! I have not used ExtremeBurner, so it's hard for me to advise you. Try other programming shells such as AVRDudesshell2019 or AVRDudess.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 25, 2023, 01:29:53 pm
Thanks both.  I will first try AVRDudesshell2019 to see if that helps to write the fuses reliably. I will come back with the result.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 25, 2023, 02:00:13 pm
Okay, I couldn't find a AVRDudesshell2019, so I just installed AVRDUDESS 2.14.  It successfully and reliably sets the fuse bits - I can set and read them as you showed now.  However, the fault still persists even with the fuse bits set as you showed.   How do I change the fuses to try to use the internal clock rather than the crystal? 
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 25, 2023, 02:42:43 pm
Try setting E2 for LOWFUSE instead of F7. This is an internal 8MHz oscillator. Do not change the other fuses.
Also show me a screenshot of the AVRDudess 2.14 window after you write the firmware files, I am interested in the messages that appear in the black box at the bottom of the window.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 25, 2023, 03:01:46 pm
Which firmware version did you want me to install on the blank 328P?  The copy of the firmware from the original 328P or the 1.12k firmware you posted?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 25, 2023, 03:18:01 pm
Better that firmware I gave you. Although the firmware you read from the original ATMega328 practically repeats it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 25, 2023, 03:24:34 pm
I used the original firmware (not sure which version it is) - it now works!  Thank you hapless and indman!  :-+ 8)  So I need to replace the original 8MHz crystal with an 8 or 16MHz crystal oscillator, correct?  Do you think I can upgrade to the latest firmware, i.e. 1.49m?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 25, 2023, 03:30:19 pm
So I need to replace the original 8MHz crystal with an 8 or 16MHz crystal oscillator, correct? Do you think I can upgrade to the latest firmware, i.e. 1.49m?
Try first to unsolder the original crystal, clean its legs well and solder it back. Don't forget to return F7 for the external quartz.
I think you do not need to update the firmware, you need to learn how to work with this firmware, it is also quite functional and stable, provided that you have no hardware problems.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 25, 2023, 03:36:16 pm
Thanks indman.  I will try this now...

If I have to replace the crystal, is there a benefit to replacing the 8MHz crystal with a 16MHz crystal?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on June 25, 2023, 03:40:17 pm
If I have to replace the crystal, is there a benefit to replacing the 8MHz crystal with a 16MHz crystal?
Yes, there are, but not so global. When replacing the crystal at 16MHz you will need a new author's firmware for this frequency. You will find the details in the author's manuals.
Title: Re: $20 LCR ESR Transistor checker project
Post by: UltimateX on June 25, 2023, 04:00:10 pm
I removed, cleaned and reinstalled the 8MHz crystal, but the white screen fault returns.  I will order a 8MHz and a 16MHz crystal as I may want to experiment with 16MHz firmware and new versions of the firmware.  Thank you very much for your help and advice.  It is very much appreciated!   :-+ :-+ :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: ayubando on June 27, 2023, 02:49:44 am
I removed, cleaned and reinstalled the 8MHz crystal, but the white screen fault returns.  I will order a 8MHz and a 16MHz crystal as I may want to experiment with 16MHz firmware and new versions of the firmware.  Thank you very much for your help and advice.  It is very much appreciated!   :-+ :-+ :-+
Check the screen pinout connection match with the new firmware pin connections
Title: Re: $20 LCR ESR Transistor checker project
Post by: ayubando on June 27, 2023, 02:51:28 am
I removed, cleaned and reinstalled the 8MHz crystal, but the white screen fault returns.  I will order a 8MHz and a 16MHz crystal as I may want to experiment with 16MHz firmware and new versions of the firmware.  Thank you very much for your help and advice.  It is very much appreciated!   :-+ :-+ :-+
Check the screen pinout connection match with the new firmware pin connections
Check the screen pinout connection match with the new firmware screen pin connections settings
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on June 28, 2023, 12:40:45 am
I removed, cleaned and reinstalled the 8MHz crystal, but the white screen fault returns.  I will order a 8MHz and a 16MHz crystal as I may want to experiment with 16MHz firmware and new versions of the firmware.  Thank you very much for your help and advice.  It is very much appreciated!   :-+ :-+ :-+
Check the screen pinout connection match with the new firmware pin connections
Check the screen pinout connection match with the new firmware screen pin connections settings
As well as clock speed and rotation, and offset and feature set... if you're the one compiling the firmware  :)

ayubando, this forum allows you to edit your own posts, so no need to double-post to make corrections.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on June 28, 2023, 02:28:23 am
For this display, a flashing with a change in font orientation. At the request of the Russian version ...

Replaced the archive with the firmware based on the results of debugging
Title: Re: $20 LCR ESR Transistor checker project
Post by: kiltro on July 03, 2023, 07:45:41 am
Hi everyone!
Is this still possibile to find this Hiland M644 version? (I'm in Europe)
Are there any newer versions?

Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on July 03, 2023, 08:38:03 am
sold out everywhere, maybe available at banggood from the beginning of august !

https://de.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 03, 2023, 01:43:21 pm
If you want to run the m-firmware with an NT7538 based display (ST7565 compatible) the reset timing needs to be adapted in function LCD_Init() in ST7565R.c:

Code: [Select]
  #ifdef LCD_RESET
    /* reset display */
      /* long reset for NT7538 (10µs/1µs) */
      /* trigger reset */
      LCD_PORT &= ~(1 << LCD_RESET);         /* set /RES low */
      wait20us();                            /* wait 20µs */
      LCD_PORT |= (1 << LCD_RESET);          /* set /RES high */
      /* wait for controller to perform reset */
      wait2us();                             /* wait 2µs */
  #endif

The next firmware version will have a setting to enable the long reset needed for the NT7538.
Title: Re: $20 LCR ESR Transistor checker project
Post by: supercap on July 17, 2023, 02:47:01 pm
Hi all!
Sorry for my poor English... :)

I prototyped the tester with one breadboard, Arduino Mega 2560 why I want to learn how work the software (version 1.49m).
I'm using Visual Studio Code and PlatformIO.

I corrected all setting (hope so) in config.h file.
I put too, the right values on #define R_LOW and R_HIGH. matching the real resistor values.

I did the Self Test and I had this values:
T1 Vref 1176mV
T1 Vref 1176mV
T1 Vref 1177mV
T1 Vref 1177mV
T1 Vref 1177mV
T2 +Rl- 12 13 23 13 18 18
T2 +Rl- 12 13 23 13 17 18
T2 +Rl- 12 13 23 13 18 18
T2 +Rl- 12 13 23 13 17 18
T2 +Rl- 12 13 23 13 18 18
T3 +Rh- 12 13 23 -2 -9 2
T3 +Rh- 12 13 23 -2 -9 2
T3 +Rh- 12 13 23 4 -11 -4
T3 +Rh- 12 13 23 -11 3 -8
T3 +Rh- 12 13 23 1 -13 -1
T3 +Rh- 12 13 23 -6 2 -13
T5 Rh- 0 0 0
T5 Rh- 0 0 0
T5 Rh- 0 0 0
T5 Rh- 0 0 0
T5 Rh- 0 0 0
T6 Rh+ 4995 4992 4995
T6 Rh+ 4993 4996 4990
T6 Rh+ 4994 4994 4996
T6 Rh+ 4992 4996 4992
T6 Rh+ 4993 4994 4996

I measured few times a film capacitor like instructions.

Self Adjustment values and first problem:

A2 R0 12 13 23 109 109 175
A2 R0 12 13 23 109 110 175
A2 R0 12 13 23 109 110 175
A2 R0 12 13 23 111 110 174
A2 R0 12 13 23 109 110 176
A2 R0 12 13 23 111 108 176
A4 Ri- 27 27 27
A4 Ri- 27 27 28
A4 Ri- 27 27 27
A4 Ri- 27 27 28
A4 Ri- 27 27 27
A5 Ri+ 132 133 134
A5 Ri+ 132 133 134
A5 Ri+ 132 133 134
A5 Ri+ 132 133 134
A5 Ri+ 132 133 134
A6 C0 12 13 23 54 51 54
A6 C0 12 13 23 54 51 54
A6 C0 12 13 23 54 51 54
A6 C0 12 13 23 54 51 54
A6 C0 12 13 23 54 51 54

Ri- 3,7 Ohm
Ri+ 18,4 Ohm
C0 53 pF
R0 0,20 Ohm
Vref 1191mV
Vcc 5001mV
AComp -8mV

Now when I push the button appear the message "Error!"
I push again the button and the tester return on menu.

I tried to test some resistors and I get wrong values:
Resistor Value | Tester Value | Real Value
100                   49,7              97
148                   72                 149
470                   477               475
560                   556               555
4,7 K                 11,8 K           4,61K
6,8 K                 17,2 K           6,71K
100 K                48 K              99K

The tester can recognize diodes, transistor, triac, ecc. with no problems.

Maybe I miss something setup when I was reading the manual of Markus Reschke? :-\
 
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 17, 2023, 06:27:05 pm
An Ri- of 3.7 Ohms is too low. There's something wrong. Have you enabled ADC_LARGE_BUFFER_CAP in config.h? The error message for the self-adjustment is caused by a too high R0 for probes #2 and #3 (A2 R0 12 13 23 109 109 175). The limit is 150 (1.5 Ohms for both in series).
Title: Re: $20 LCR ESR Transistor checker project
Post by: supercap on July 17, 2023, 08:00:44 pm
An Ri- of 3.7 Ohms is too low. There's something wrong. Have you enabled ADC_LARGE_BUFFER_CAP in config.h? The error message for the self-adjustment is caused by a too high R0 for probes #2 and #3 (A2 R0 12 13 23 109 109 175). The limit is 150 (1.5 Ohms for both in series).

Thank you Madires for you very fast reply.
Tomorrow I will check for the ADC_LARGE_BUFFER_CAP option.
About pin resistances, I will try to change the wires with not crimped one. This because I have found some days ago, one wire with inusual resistance... 8)
Title: Re: $20 LCR ESR Transistor checker project
Post by: supercap on July 18, 2023, 04:03:04 pm
I enabled ADC_LARGE_BUFFER_CAP and changed wires, now resistor values are ok!
Still present some problems on "big" capacitors:
Value | Tester Value | Real Value  | Type

100uF    76,12           100,4           electrolytic
220uF    165,9           225,0           electrolytic
47uF      39,19           51,25           electrolytic
10nF      10,26           10,53           polyester
330nF    316,2           318              polyester
150pF    155pF           154              tantalum

Maybe I miss something again...  |O

I can find somewhere a schematic diagram of this tester with all functions with Mega 2560 controller?

I wanna use this post too for make my big compliments for the clean code written by Madires. You did a really big work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 18, 2023, 04:11:19 pm
Maybe I miss something again...

Yes, here is the part of the madires manual that will help you

"* Capacitors

The measurement of capacitance is split into three methods. Large caps >47µF
are measured by the charging cycle method with 10ms pulses. Mid-sized
caps between 4.7µF and 47µF are processed the same way but with 1ms charging
pulses. And small caps are done by the analog comparator method. That
way the accuracy of the measurement of caps is optimized.

Large capacitances require a correction. Without correction the measured values
are too large. IMHO, that is caused by the measurement method, i.e. the ADC
conversion after each charging pulse needs some time and the cap looses charge
due to internal leakage during the same time. Also the ADC conversion itself
needs some charge to operate. So it takes longer to charge the cap, and the cap
seems to have a larger capacitance. A discharge measurement later on tries to
compensate this, but is able to do it just partially. The correction factors (
CAP_FACTOR_SMALL, CAP_FACTOR_MID and CAP_FACTOR_LARGE in config.c) are choosen
to work with most tester models. In some cases you might have to change them."
Title: Re: $20 LCR ESR Transistor checker project
Post by: supercap on July 18, 2023, 07:43:26 pm
Maybe I miss something again...

Yes, here is the part of the madires manual that will help you

"* Capacitors

The measurement ...

Large capacitances require a correction. Without correction the measured values
are too large. IMHO, that is caused by the measurement method, i.e. the ADC
conversion after each charging pulse needs some time and the cap looses charge
due to internal leakage during the same time. Also the ADC conversion itself
needs some charge to operate. So it takes longer to charge the cap, and the cap
seems to have a larger capacitance. A discharge measurement later on tries to
compensate this, but is able to do it just partially. The correction factors (
CAP_FACTOR_SMALL, CAP_FACTOR_MID and CAP_FACTOR_LARGE in config.c) are choosen
to work with most tester models. In some cases you might have to change them."

Thank you indman!
Yes I read this, but there is write "Without correction the measured values
are too large". In my case, I have small values not large one.
For this I was think about some other problems...
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 19, 2023, 05:23:09 am
Yes I read this, but there is write "Without correction the measured values
are too large". In my case, I have small values not large one.
You have a ARDUINO MEGA2560 and you have enabled the ADC_LARGE_BUFFER_CAP option, so you will need to correct capacitance readings on various bands anyway.

"CAP_FACTOR_SMALL, CAP_FACTOR_MID and CAP_FACTOR_LARGE in config.c"
Madires, there is a small error in Readme - instead of config.c, config.h is meant.
Title: Re: $20 LCR ESR Transistor checker project
Post by: supercap on July 19, 2023, 01:36:19 pm
Thank you indman, with a little setup on CAP_FACTOR_LARGE option I resolved this problem too.
Now last problem...
If I try to use DATA_EEPROM for store data in EEPROM, my tester don't work.
My display appear empty, after some second appear the text "2: 5v".
Is like the firmware cant store the data in the right mode...
If i double press the button for enter in menu, appear ":", then the moving pointer "*".
Is like the text are not stored in EEPROM?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 20, 2023, 12:46:15 am
Are you flashing both the program file and the EEPROM file or just the program? You need both.

Also, check the MCU speed in the makefile. If it says "FREQ = 16" and your crystal is 8MHz, you will have wrong measurements no matter what else you try.
Title: Re: $20 LCR ESR Transistor checker project
Post by: TankedThomas on July 21, 2023, 02:37:09 pm
I just got a T7 with what I believe is an LGT8F328 (QFP32L) and was wondering if someone can please help me with reprogramming it.
Since there's the WIP firmware for this chip, I was going to give that a try, but since it doesn't use ISP, I have no idea how to connect it to a programmer.

I soldered a 5-pin header onto the board but haven't managed to get neither Arduino nor AVRDUDE to read it.
I probably have the pinout wrong but it's hard to find any specifics about what to connect where in order to dump and flash the chip (assuming that's possible).

I'm using a Raspberry Pi because it's the most convenient, though I have a regular USBasp 2x3P connector as well, and some Arduino-compatible boards if necessary (Teensy 2.0++ and ESP8266).
If someone can please point me in the right direction, that'd be really helpful. I couldn't find anyone else trying to do this, though this thread is pretty large so I haven't read every single post (yet).
Maybe replacing it with the Atmega328p is a better idea but I'm not sure if it's worthwhile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on July 21, 2023, 03:09:12 pm
Since there's the WIP firmware for this chip
What firmware, which is tested and fully functional, are you going to program into the LGT8F328 chip?
My advice - do not waste your time, but change the chip to a classic ATMega328, for which there are author's working firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: elecdonia on July 21, 2023, 06:35:50 pm
Since there's the WIP firmware for this chip
What firmware, which is tested and fully functional, are you going to program into the LGT8F328 chip?
My advice - do not waste your time, but change the chip to a classic ATMega328, for which there are author's working firmware.
I agree with indman. At this point in time I think it will be far easier to replace the LGT8F328 with an Atmel ATmega328P. The required PC board modification is relatively simple.

I obtained a quantity of LGT8F328 "Arduino compatible" boards. These boards resemble the Arduino Pro-mini. They come with a bootloader installed and are programmed with a standard USB-TTL adaptor. I was curious to see what they are like. So far I succeeded at programming them after installing the LGT8F328 "boards" package into the Arduino IDE. These boards will run many standard Arduino sketches (such as "blink").

But I think it will still require considerable time and effort to modify existing Transistor Tester software for the LGT8F328.     
Title: Re: $20 LCR ESR Transistor checker project
Post by: supercap on July 28, 2023, 09:07:47 am
Are you flashing both the program file and the EEPROM file or just the program? You need both.

Also, check the MCU speed in the makefile. If it says "FREQ = 16" and your crystal is 8MHz, you will have wrong measurements no matter what else you try.

Hi hapless,
I do not compile the program with the makefile.
I'm using Visual Studio Core and PlatformIO and to be honest is hard for me understand why I have to flash EEPROM too: the program store the data in EEPROM with the files var_italian.h, variables.h.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 28, 2023, 09:39:19 am
I do not compile the program with the makefile.
You are creating problems for yourself. Here are my programs for writing code in arduino mega 2560...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 28, 2023, 10:23:02 am
I'm using Visual Studio Core and PlatformIO and to be honest is hard for me understand why I have to flash EEPROM too: the program store the data in EEPROM with the files var_italian.h, variables.h.

The text/strings can change between versions (rarely tables and other data). It will also vary with the featues enabled/disabled. And compilers can rearrange data (we don't use fixed addressing).
Title: Re: $20 LCR ESR Transistor checker project
Post by: supercap on July 28, 2023, 11:39:38 am
You are creating problems for yourself. Here are my programs for writing code in arduino mega 2560...

I think not, why PlatformIO and his debug is the best way for me to learn how the program work. :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: supercap on July 28, 2023, 11:44:47 am
The text/strings can change between versions (rarely tables and other data). It will also vary with the featues enabled/disabled. And compilers can rearrange data (we don't use fixed addressing).

Hmm, yes I start to think about some problem with compilator...
When I have time I will try to debug step by step and check the memory for find the problem.
Title: Re: $20 LCR ESR Transistor checker project
Post by: supercap on July 29, 2023, 08:16:38 am
I resolved my problem with DATA_EEPROM option.
The user hapless give me a input.
Some days ago PlatformIO released a new version.
So I found in Project tasks a function to upload the EEPROM too.
I tried and all was work fine.
I really appreciate your all help!
Thak you.

Last question, is there some way to make the LCD refresh more faster?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on July 29, 2023, 10:12:07 am
If you are already using hardware SPI with the 16MHz Mega2560 you could try a display with a parallel bus.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on July 29, 2023, 07:47:43 pm
Something slightly different...
https://dragaosemchama.com/en/2019/04/gm328a-reverse-engineering-new-firmware-and-tetris/ (https://dragaosemchama.com/en/2019/04/gm328a-reverse-engineering-new-firmware-and-tetris/)

I tried the Tetris game, and it works well enough, but the piezo speaker got ripped out of the PWM output early on for sanity's sake.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Piotrix on July 29, 2023, 10:32:23 pm
Good evening everybody , This is my first post on EEVblog, though I am  lurker for many years

  Question:
Which tester to buy nowadays and not get a fake Atmel chip? ,  I understand that these 2:
  aliexpress.com/item/1005003606018640.html or
  aliexpress.com/item/1005003678038543.html
  (GM328A the one with terminals on both sides of the PCB) ,  are right, are they?
  By the way, what is the difference between them. As far as I understand the difference is only in LCD screen, but what is exactly the difference?

Or is it better to buy an assembly kit, and then I can chose  resistors and caps with tighter specs   for more accurate measurements. Like this one: aliexpress.com/item/32706710335.html
Basically what I want is a real Atmel chip + the ability modify the tester to get the most reliable and accurate measurements.
Which way should I  go?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on July 30, 2023, 07:38:49 am
Like this one: aliexpress.com/item/32706710335.html
Basically what I want is a real Atmel chip + the ability modify the tester to get the most reliable and accurate measurements.
Which way should I  go?
The kit uses a display that allows the use of 16 MHz quartz. In the previous examples, you can get a BGR display that works with only 8 MHz quartz ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 01, 2023, 12:58:30 pm
A treat for the summer break:

v1.50m
- Removed temporary option UI_PROBE_REVERSED_X as it's not needed anymore.
- Option to display battery status in the last line after showing the probing result (UI_BATTERY_LASTLINE).
- Option to display a small battery symbol to indicate the battery status (UI_BATTERY).
- Added battery symbols to most fonts. Also supplemented some fonts with probe numbers with reversed foreground/background.
- Added option for a long reset pulse for an NT7538 LCD controller to the ST7565R driver (LCD_LONG_RESET).
- Added test function for photodiodes (SW_PHOTODIODE).
- Option to scroll menues page-wise instead of item-wise (UI_MENU_PAGEMODE, suggested by indman@EEVblog). Speeds up menu operation with graphics displays.
- Added two new colors to colors.h (COLOR_PALE_GREEN, COLOR_PALE_RED, suggested by .RC.@EEVblog).
- Updated Brazilian Portuguese texts (thanks to wandows@EEVblog).
- Updated Russian texts (thanks to indman@EEVblog).
- Updated Polish texts #2 (thanks to Jacon@EEVblog).
- Updated Spanish texts (thanks to pepe10000@EEVblog).

Please download at:
- https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
- https://github.com/kubi48/TransistorTester-source/tree/master/Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: pepe10000 on August 01, 2023, 04:00:32 pm
Hello.

Thank you madires for the gift for the summer holidays.

Attached the update of the Spanish language file with the latest news.

All the best.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 01, 2023, 07:39:52 pm
Thanks madires! :-+
I have updated the Russian translation of the pdf documentation for version 1.50m as well as the language file. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on August 02, 2023, 03:24:49 pm
Thanks madires! :-+

Checked the v1.50m  on the HilandM644 color variant. There is a warning, do not use

/*
 *  fixed cap for self-adjustment
 *  - see TP_CAP and ADJUST_PORT in config-<MCU>.h for port pins
 *  - uncomment to enable
 */

//#define HW_ADJUST_CAP 

Error! - after adjustment

Haven't found any other comments yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 02, 2023, 03:59:32 pm
Is the cap for self-adjustment an MLCC? If so, please try a film cap.
Title: Re: $20 LCR ESR Transistor checker project
Post by: siealex on August 02, 2023, 07:23:51 pm
1.50m, GM328A with ATmega in a DIP case. Strange behavior in the Generator mode: rotating the encoder knob exactly by one step changes the frequency in an unpredictable way, e. g. twice, in the opposite direction, by a random step or all the way up to 2 MHz. In other modes the encoder behaves correctly. Do I have wrong encoder settings or is it a bug in the generator mode?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on August 02, 2023, 08:01:05 pm
Is the cap for self-adjustment an MLCC? If so, please try a film cap.
Thanks Madires! :-+   I picked up a capacitor by analogy with a film capacitor MLCC. Everything began to work correctly. Shown in pictures...
The previously standing capacitor worked normally for more than 3 years. I don’t know what happened to him, but the readings differ from those shown in the right picture.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 02, 2023, 08:06:27 pm
1.50m, GM328A with ATmega in a DIP case. Strange behavior in the Generator mode: rotating the encoder knob exactly by one step changes the frequency in an unpredictable way, e. g. twice, in the opposite direction, by a random step or all the way up to 2 MHz. In other modes the encoder behaves correctly. Do I have wrong encoder settings or is it a bug in the generator mode?

Could be the encoder settings or a cheap/dirty/worn encoder. Since the encoder's turning speed impacts the frequency change in the signal gen (faster -> larger change) any issues will be more visible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: siealex on August 02, 2023, 08:37:00 pm
No, it was in fact a wrong setting: 2 pulses per notch instead of 4. Now the behavior is way more adequate in all modes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: siealex on August 02, 2023, 11:31:27 pm
A couple of questions on color graphic displays.
1. Is it possible to type text with 1 px offset from all edges? If I define a global offset, that line is not cleared at all and displays garbage.
2. Can small fonts (8x8) be upscaled twice vertically without losing flash space?
Title: Re: $20 LCR ESR Transistor checker project
Post by: siealex on August 02, 2023, 11:47:03 pm
A small visual bug. Graphic display, 8*8 font (font_8x8_iso8859-2_hf.h). Character "q" is shifted one pixel right, it should be:
 0x00,0x7E,0x63,0x63,0x63,0x73,0x6E,0x60,   /* 0x61 q */
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 03, 2023, 09:46:16 am
1. Is it possible to type text with 1 px offset from all edges? If I define a global offset, that line is not cleared at all and displays garbage.

You could modify the display driver to do that. However, it would be only possible for display controllers supporting address windows, but no for controllers with pages (8 bits heigh addressing bars).

2. Can small fonts (8x8) be upscaled twice vertically without losing flash space?

That should be feasible with a driver modification (see LCD_Symbol() of a driver supporting SYMBOL_RESIZE).
Title: Re: $20 LCR ESR Transistor checker project
Post by: tofof on August 04, 2023, 09:46:45 pm
What is the current consensus on the better chip for this project, a 324 or a 328? I have contacted many vendors of the T2 through ebay requesting board photos, to see if any of them do indeed have a genuine 324 inside as a few posters have managed to luck into. Alternatively, the german Joy-It T7 seems to be a safe way of getting a 328.

Is there any compelling advantage of one of these chips over the other?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 05, 2023, 10:38:50 am
The ATmega324 has more I/O pins which is great for addtional hardware options and driving a display via hardware SPI. Unfortunately, the pin assignment of tester clones is regularly screwed up and you won't get hardware SPI without some modifications.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Jacon on August 06, 2023, 11:30:34 am
Hi Marcus & T-Checkers,

Attached please find updated Polish translation file  :)
Good for discovering photovoltaic effect in various elements  :-+

Title: Re: $20 LCR ESR Transistor checker project
Post by: TankedThomas on August 07, 2023, 09:08:28 am
Since there's the WIP firmware for this chip
What firmware, which is tested and fully functional, are you going to program into the LGT8F328 chip?
My advice - do not waste your time, but change the chip to a classic ATMega328, for which there are author's working firmware.
I don't believe it's fully functional nor up-to-date, but this is the firmware I was thinking of: https://github.com/DurandA/transistor-tester-lgt328p

To be honest, I don't think I have the skills to remove and solder SMD chips. My eyesight isn't great (though I do have a microscope I can use) and I don't currently have rework equipment, though I do plan to get a hot air gun for it soon.

I agree with indman. At this point in time I think it will be far easier to replace the LGT8F328 with an Atmel ATmega328P. The required PC board modification is relatively simple.

I obtained a quantity of LGT8F328 "Arduino compatible" boards. These boards resemble the Arduino Pro-mini. They come with a bootloader installed and are programmed with a standard USB-TTL adaptor. I was curious to see what they are like. So far I succeeded at programming them after installing the LGT8F328 "boards" package into the Arduino IDE. These boards will run many standard Arduino sketches (such as "blink").

But I think it will still require considerable time and effort to modify existing Transistor Tester software for the LGT8F328.   
I'm not sure how to make the modifications required to swap the chips and use a full 6 pin header though - maybe the instructions are in this thread but I didn't see them when looking. If I understand correctly at least two of the pins have to be swapped.

I just have Raspbian Lite (i.e. CLI-only) installed on my main Raspberry Pi, so I don't have the full Arduino IDE to use (I do on Windows but I don't know how I'd hook the tester up to my PC), but even so, I think it's just a matter of me not knowing how to hook up the wires properly to the GPIO pins.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on August 07, 2023, 03:40:06 pm
To everyone who uses my firmware. You can correctly identify JFET pins by looking at smaller Cg= readings ... Sample measurement in the picture...
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 07, 2023, 03:54:48 pm
Yuriy_K,this is certainly good, but I don’t understand how knowing the correct drain and source will fundamentally change the way JFETs work, in which the channel has a symmetrical structure?
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on August 12, 2023, 01:02:45 pm
hello everyone
I compiled V1.50m and tried to test the DHT22 with my LCR-T4 and it was always detected as DHT11 and showed erroneous temperature and humidity so i checked the DHTxx.c code and found that it defaulted to DHT11 and i have to long-press the button twice to switch first to auto-mode then to the DHT22 sensor  which is not straightforward. i suggest 2 ways to solve this issue:
- add a submenu to select between DHT11 and DHT22
- use the fact that byte 2 and byte 4 in the DHT 11 are always 0 to make a 99% accurate guess between dth11 and dht22
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 12, 2023, 01:11:36 pm
moimem,maybe the Test button works badly or unreliably?
I don't see any difficulty in the standard madires solution for picking the sensor type.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 12, 2023, 01:25:58 pm
Or you could have simply read the README file which explains the operation of the DHTxx tool?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on August 13, 2023, 08:34:01 pm
Is the GM328A able to test horn caps (e.g. 82V 15000uF)? I'm aware of the 5V, 7mA limit (regarding diacs, triacs) as stated in the manual but i'm not sure if this affects caps as well as the 82V is just the max voltage.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 13, 2023, 08:53:43 pm
Should be able to measure the capacitance (needs some time, be patient). I guess the ESR is going to be too low.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on August 13, 2023, 09:44:46 pm
Should be able to measure the capacitance (needs some time, be patient)
Still enough to figure out if its still in good shape i guess. That would be ok.

I guess the ESR is going to be too low.
You mean the on-screen ESR value not the real/technical ESR characteristics (that might lead to test abortion or sth), right?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 14, 2023, 06:25:26 am
Is the GM328A able to test horn caps (e.g. 82V 15000uF)? I'm aware of the 5V, 7mA limit (regarding diacs, triacs) as stated in the manual but i'm not sure if this affects caps as well as the 82V is just the max voltage.
The tester is capable of measuring capacitances up to 100000uF and the model of the tester does not matter. The approximate test time for such a large capacity is 40-50 seconds. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 14, 2023, 08:56:51 am
You mean the on-screen ESR value not the real/technical ESR characteristics (that might lead to test abortion or sth), right?

No, both. The tester's lower limit is 0.01 Ohms and anything below that will be shown as 0 Ohms. When there's a problem with the ESR measurement nothing bad happens. IIRC, the k-firmware displays 0 Ohms in that case, while the m-firmware simply doesn't show the ESR value.
Title: Re: $20 LCR ESR Transistor checker project
Post by: xfint34 on August 16, 2023, 12:41:47 am
I checked the firmware size using the major GCC versions from GCC 12 going back to GCC 4.8.5. GCC 8.5.0 generates the smallest firmware size. A bit better than the commonly used GCC 7.3.0 for compiling these firmwares.

The results are a bit better with the m firmware. 160 bytes smaller. With k firmware it is only 26 bytes smaller.

1.50m firmware:
Code: [Select]
avr-gcc --version
avr-gcc (GCC) 7.3.0

AVR Memory Usage
----------------
Device: atmega328

Program:   27132 bytes (82.8% Full)
(.text + .data + .bootloader)

Data:        226 bytes (11.0% Full)
(.data + .bss + .noinit)

EEPROM:      749 bytes (73.1% Full)
(.eeprom)



avr-gcc --version
avr-gcc (GCC) 8.5.0

AVR Memory Usage
----------------
Device: atmega328

Program:   26972 bytes (82.3% Full)
(.text + .data + .bootloader)

Data:        226 bytes (11.0% Full)
(.data + .bss + .noinit)

EEPROM:      749 bytes (73.1% Full)
(.eeprom)


1.13k firmware:
Code: [Select]
avr-gcc --version
avr-gcc (GCC) 7.3.0

AVR Memory Usage
----------------
Device: atmega328p

Program:   31454 bytes (96.0% Full)
(.text + .data + .bootloader)

Data:        204 bytes (10.0% Full)
(.data + .bss + .noinit)

EEPROM:      875 bytes (85.4% Full)
(.eeprom)

avr-gcc --version
avr-gcc (GCC) 8.5.0

AVR Memory Usage
----------------
Device: atmega328p

Program:   31428 bytes (95.9% Full)
(.text + .data + .bootloader)

Data:        204 bytes (10.0% Full)
(.data + .bss + .noinit)

EEPROM:      875 bytes (85.4% Full)
(.eeprom)

Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on August 16, 2023, 09:20:14 pm
If the GM328A has a 16MHz crystal but the external ISP flasher dev board only an 8MHz crystal. Is it possible to flash a 16MHz firmware with an 8MHz board?
Edit: Maybe the 8MHz crystal is only used when running (not flashing) the chip on the dev board itself? The ISP pinout includes SCK (serial clock). Shouldn't that be the clock frequency (independent from crystal) provided by the ISP flasher itself?

Flasher:
https://www.aliexpress.com/item/1005001655965219.html (https://www.aliexpress.com/item/1005001655965219.html)
https://www.aliexpress.com/item/32582933115.html (https://www.aliexpress.com/item/32582933115.html)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 17, 2023, 01:01:46 am
Shouldn't make any difference.
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on August 17, 2023, 03:08:06 pm
Find attached simple french translation (without special letters: é è à ^¨ etc...) that work without dedicated fonts
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxaM on August 18, 2023, 11:46:37 am
Good morning, this is my first post although I have been following you for a long time.

I need your help: can someone kindly compile the latest firmware for GM328A (v1.50m) for 20Mhz quartz?
I am not very experienced in linux and on Windows I can't. Thank you in advance!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on August 20, 2023, 06:35:41 pm
can someone kindly compile the latest firmware for GM328A
If you post your configs (or the diffs) it might be possible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: VEGETA on August 21, 2023, 10:04:18 am
hello,

i am planning to get one of these, mainly to test capacitors and their ESR.

I found this on amazon: https://www.amazon.com/Transistor-DROK-Capacitor-Capacitance-Automatic/dp/B01MS1FOYM/ (https://www.amazon.com/Transistor-DROK-Capacitor-Capacitance-Automatic/dp/B01MS1FOYM/)

is this good? also, can it be software updated? I do have pic and atmel programmer on hand.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ledtester on August 21, 2023, 11:48:37 am
Have a look at this comparison chart:

https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf (https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf)

Compared to other models the  one you are interested in lacks input protection and only tests zener diodes up to 5V.

It may contain a genuine Atmel MCU. Since you buying from Amazon you might be able to disassemble it, check and return it if it doesn't.

For mesuring ESR I'd take a look at the 5 transistor ESR meter project:

https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/ (https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/)


Title: Re: $20 LCR ESR Transistor checker project
Post by: VEGETA on August 21, 2023, 12:35:56 pm
Have a look at this comparison chart:

https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf (https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf)

Compared to other models the  one you are interested in lacks input protection and only tests zener diodes up to 5V.

It may contain a genuine Atmel MCU. Since you buying from Amazon you might be able to disassemble it, check and return it if it doesn't.

For mesuring ESR I'd take a look at the 5 transistor ESR meter project:

https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/ (https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/)

I am interested in a good form-factor thing, not bare board.

I couldn't find LCR-TC2 on amazon but found this one: https://www.amazon.com/Transistor-Aideepen-Multi-Function-Capacitor-Resistor/dp/B08YNJYWCW/ (https://www.amazon.com/Transistor-Aideepen-Multi-Function-Capacitor-Resistor/dp/B08YNJYWCW/)

it looks like TC1 model, right?

it has "-H" variant which supposed to be upgraded specs and so on. USB power is always better than battery.

what do you think about this model?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 21, 2023, 01:52:58 pm
We can't give any recommendations on specific tester clones at the moment because many of them come with alternative MCUs and a poorly adapted firmware. Some lack the self-adjustment feature, and there are measurement issues with ESR and other values. The most important thing is to get a tester with a genuine ATmega.
Title: Re: $20 LCR ESR Transistor checker project
Post by: VEGETA on August 21, 2023, 04:54:53 pm
We can't give any recommendations on specific tester clones at the moment because many of them come with alternative MCUs and a poorly adapted firmware. Some lack the self-adjustment feature, and there are measurement issues with ESR and other values. The most important thing is to get a tester with a genuine ATmega.

ok then what is the recommended product to get? not bare board
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 21, 2023, 07:41:15 pm
Any tester clone with a genuine ATmega, as I already explained.
Title: Re: $20 LCR ESR Transistor checker project
Post by: VEGETA on August 21, 2023, 09:44:56 pm
Any tester clone with a genuine ATmega, as I already explained.

well, I need to buy from amazon this time since it deals with customs automatically for us in Jordan without headache.

I think I should just get the H version: https://www.amazon.com/Transistor-Aideepen-Multi-Function-Capacitor-Resistor/dp/B07RZRSBC5/?th=1 (https://www.amazon.com/Transistor-Aideepen-Multi-Function-Capacitor-Resistor/dp/B07RZRSBC5/?th=1)

All I need to to check caps and their ESR (or ESL if possible?) reasonably accurate... no need to update it if it does the job well.

if you know any store selling a superior version with genuine atmel MCU please link it.

Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on August 22, 2023, 02:01:08 am
Instead of playing the lottery and very possibly losing (who knows what's inside that "LCR-Txx" thing!), why not just buy a dedicated ESR meter instead? Sounds like you need a DE-5000 or something like that, not the component analyzer that this thread is about.
Title: Re: $20 LCR ESR Transistor checker project
Post by: VEGETA on August 22, 2023, 05:06:49 am
Instead of playing the lottery and very possibly losing (who knows what's inside that "LCR-Txx" thing!), why not just buy a dedicated ESR meter instead? Sounds like you need a DE-5000 or something like that, not the component analyzer that this thread is about.

well, a component tester is more versatile and offers much more than just an esr meter + cheaper. i am not a hardcore user anyway.

i searched for a professionally made component tester but could not find one, only the one in this thread and its clones are available.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on August 22, 2023, 08:11:41 am
I've recently used (not mine) a TC-7 and a TC-7H. Both used non ATmega processors and the TC-7H didn't even have a self calibration routine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 22, 2023, 08:20:24 am
VEGETA Currently these models are not available on Amazon, but you can focus on buying these clones with a solid case and sufficient functionality. At least until that time, none of the buyers complained that a non-original ATMEGA328 was installed on the board.

BSIDE ESR02 PRO Transistor SMD Diode Triode Capacitor MOSFET Resistor Inductance LCR ESR
https://www.amazon.com/dp/B07MKRBW2S/ref=cm_sw_r_cp_api_glt_i_68KT99GVRAE5G0C3K6FZ?psc=1 (https://www.amazon.com/dp/B07MKRBW2S/ref=cm_sw_r_cp_api_glt_i_68KT99GVRAE5G0C3K6FZ?psc=1)

MK-328 Transistor Capacitor ESR Inductance Resist LCR NPN PNP MOS
https://www.amazon.com/dp/B09132HM31/ref=cm_sw_r_cp_api_glt_i_1AB3MQRWT310Y9BT5G86?_encoding=UTF8&psc=1 (https://www.amazon.com/dp/B09132HM31/ref=cm_sw_r_cp_api_glt_i_1AB3MQRWT310Y9BT5G86?_encoding=UTF8&psc=1)
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxaM on August 22, 2023, 11:04:46 am
can someone kindly compile the latest firmware for GM328A
If you post your configs (or the diffs) it might be possible.

Thank you for your interest, currently I'm using the 1.45mEnMod2(20Mhz) version and I'm quite happy, I just wanted to browse and test the new version, if you can take a look at the 1.45mEnMod2(20Mhz) version and compile the 1.50 m with the same configurations I would be grateful. Thank you!
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on August 22, 2023, 04:07:02 pm
Thank you for your interest, currently I'm using the 1.45mEnMod2(20Mhz) version and I'm quite happy, I just wanted to browse and test the new version, if you can take a look at the 1.45mEnMod2(20Mhz) version and compile the 1.50 m with the same configurations I would be grateful. Thank you!

GM328A_1.50mEnMod2(20Mhz)_UNTESTED!!!
 some faitures needed to be removed to fit the firmware in the flash, try at your own risk!
Unfortunatly the atmega328P cant fit all the faitures of the firmware, the best you can do is try to build your own firmware with the faitures you like, its very eazy and well documented in this thread,and  you have already the config files provided in 1.45mEnMod2(20Mhz).zip
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 22, 2023, 04:15:15 pm
GM328A_1.50mEnMod2(20Mhz)_UNTESTED!!!
You will not be able to compile the same firmware as I did in 1.45Mod2 because the configuration files I put in the archive only for example.And also because this is a MODIFIED firmware and most of the author's source files have been changed.This is the main difference between the original firmware and modified. The most important thing is that these changes do not violate the functionality and proper operation of the author's algorithm. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on August 22, 2023, 04:32:59 pm
Thats true, i didnt use those exact files but used them as a base with the clones file in the firmware source to modify the stock config files of the 1.50m firmware, you can find attached those exact files
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxaM on August 22, 2023, 05:44:12 pm
Quote
GM328A_1.50mEnMod2(20Mhz)_UNTESTED!!!
...try at your own risk!

Thank you guys for your help and excuse my ignorance, what do you mean by test at your own risk? If it doesn't work I can always reprogram with GM328A_1.45mEnMod2(20Mhz) and restore the device, right? Or could irreversible problems arise?
Finally, to program the atmega328p, in addition to the file GM328A_1.50mEnMod2(20Mhz)_UNTESTED.hex wouldn't I also need a file like "ComponentTester.eep"? Please explain to me... Thanks again!
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on August 22, 2023, 11:21:58 pm
what do you mean by test at your own risk?
its just a warning since i have only compiled the firmware and coudn't test it, you can always reflash any firmware if something go wrong. My bad for the missing attachement, here is the full firmware with the config files if you want to try compiling it yourselft.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxaM on August 23, 2023, 10:40:45 am
moimem THANK YOU!

Firmware tested and working, although I didn't quite understand the main differences with the 1.45m apart from the graphic aspect (honestly as colors and graphics I personally preferred the 1.45m) anyway everything works perfectly and the measurements are correct. Finally I was wondering: among the various firmware versions out there is there any that allows quartz testing? Thank you again for your time.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 23, 2023, 11:16:41 am
For testing quartz crystals you can run the k-firmware with the SamplingADC feature or get a tester with the extended frequency counter option (e.g. Hiland M644, supported by both OSHW firmwares). BTW, there are many options for the m-firmware to change/optimize the user interface for your needs, including colors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vitiv on August 23, 2023, 12:00:18 pm
Hi I'm new here. After several days reading this thread, I have finally reached the end, with many doubts, different from those before I started reading.
I have a kit on the way from china (supposedly a Mega328 DIP) and just realized I don't know what type of screen it is. Does anyone know how to distinguish them by photo? I attach one.


On the other hand, after following years of answers in the thread, it seems that the m328 is in a terminal state, lack of stock, lack of memory...
Has anyone thought of creating a pcb with all the new options and a mega644/1284? It may be that for all the options there are no entries but it occurs to me to leave one empty and create plug-in modules, for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 23, 2023, 01:55:22 pm
You have an AY-AT/GM328A with an ST7735 based display. If the display PCB has an MCU then it's an ST7735 semi-compatible. There are already testers with ATmega644 (e.g. Hiland M644), but please feel free to design a new PCB.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on August 23, 2023, 02:03:54 pm
There are already testers with ATmega644 (e.g. Hiland M644), but please feel free to design a new PCB.
There is no need to develop a new PCB, since a simple DIP28-TQFP adapter for ATMega644/1284 can be made for this clone. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: vitiv on August 23, 2023, 03:13:35 pm
You have an AY-AT/GM328A with an ST7735 based display. If the display PCB has an MCU then it's an ST7735 semi-compatible.

Do they only differ by looking at whether it has the MCU?  :scared:

There are already testers with ATmega644 (e.g. Hiland M644), but please feel free to design a new PCB.

Yeah, I feel free to design a new PCB, but I haven't designed one in 40 years, what I don't have is the spirit. :o The Hiland M644 there is no way to get it and your extra options are missing. :-//

There are already testers with ATmega644 (e.g. Hiland M644), but please feel free to design a new PCB.
There is no need to develop a new PCB, since a simple DIP28-TQFP adapter for ATMega644/1284 can be made for this clone. ;)

Yes, I already saw the adapter, but unused pins remain and you have to change the code. If I see myself with strength, surely I will get one to test, but one is already old, sees badly and makes more fatal errors than successes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 23, 2023, 03:39:57 pm
You have an AY-AT/GM328A with an ST7735 based display. If the display PCB has an MCU then it's an ST7735 semi-compatible.
Do they only differ by looking at whether it has the MCU?  :scared:

Both come usually with a 3.3V LDO and a level-shifter. One is a genuine ST7735 display, and the other has an additional MCU to emulate the ST7735.
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxaM on August 23, 2023, 03:44:51 pm
For testing quartz crystals you can run the k-firmware...

About firmware K and related files for compilation (config.h, config_328.h, Makefile) do you have any links where I can retrieve it? I would appreciate it...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 23, 2023, 05:21:46 pm
Source code: https://github.com/kubi48/TransistorTester-source/tree/master/trunk
Dokumentation: https://github.com/kubi48/TransistorTester-documentation
Settings for the k-firmware are all done in the Makefile.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on August 23, 2023, 10:52:37 pm
...I didn't quite understand the main differences with the 1.45m apart from the graphic aspect (honestly as colors and graphics I personally preferred the 1.45m)
Download the latest firmware source from here:
https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
Then open the 'changes' file to see the change log of each version.
Also you might open and examine these files to get familiar with the options you have: config_328.h, config.h, Makefile
Title: Re: $20 LCR ESR Transistor checker project
Post by: MaxaM on August 24, 2023, 02:42:18 pm
Quote
Also you might open and examine these files to get familiar with the options you have: config_328.h, config.h, Makefile

Sorry, honestly I have never edited a Makefile, I would need your help, to activate
SamplingADC for quartz test what should I put in the Makefile?

(https://i.snipboard.io/dU2QAP.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 25, 2023, 08:06:21 am
It's already enabled.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on August 25, 2023, 01:40:42 pm
Sorry, honestly I have never edited a Makefile, I would need your help, to activate
SamplingADC for quartz test what should I put in the Makefile?
Looks like you have a modified makefile. In the original makefile that section looks like this:
Code: [Select]
# Option WITH_XTAL enables additional Xtal / Ceramic resonator tests.
# Option can be set only together with SamplingADC=1 and OP_MHZ=16
#CFLAGS += -DWITH_XTAL

See reply #8784 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5026024/#msg5026024) of Madires above. Download and examine the pdf document and the makefile inside the mega328_GM328 folder. Also examine the readme file inside the m-firmware source. Probably you'll find all the answers and you can learn how to compile, it's not difficult. Then you can experiment with different configuratons and try them on your tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on August 26, 2023, 03:49:25 pm
Or is it better to buy an assembly kit, and then I can chose  resistors and caps with tighter specs   for more accurate measurements. Like this one: aliexpress.com/item/32706710335.html
I ordered this (12Eur). Shipped to Germany in 9 days. Has 16MHz quartz.

The sellers assembly instructions are on a chinese cloud storage service though that only allows low-quality preview for unregistered users. For assembling its ok but the schematics.pdf (kicad) resolution is too low. I couldn't manage to register there (they request mobile phone number).

https://www.aliexpress.com/item/32706710335.html (https://www.aliexpress.com/item/32706710335.html)
https://www.jianguoyun.com/p/Df9U95oQweDQCxjm0YcFIAA (https://www.jianguoyun.com/p/Df9U95oQweDQCxjm0YcFIAA)

Is someone already registered there or can hack it or whatever to get the high resolutions schematics.pdf?

Edit:
1) Is there an overview/gallery somewhere that shows all the alternative icons and font sizes?
2) How to re-flash the Atmega328P DIP without in-circuit ISP? Or in other words, any good advice how to remove the chip easily out of the socket again (without an official pull tool)? I'm planning to put some strings under the chip to carefully lift it up. I once done that on PLCC Bios chips (hotswap flashing).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 26, 2023, 05:24:59 pm
That's an AY-AT/GM328A. You'll find the schematic and more at https://disk.yandex.ru/d/yW8xa5NJgUo5z/M328Kit%2BTFT. We don't have a gallery of all the fonts and symbols. If you like to program the ATmega out of circuit you can use an universal programmer or an ISP programmer plus adapter board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vitiv on August 27, 2023, 01:26:49 am
Is someone already registered there or can hack it or whatever to get the high resolutions schematics.pdf?
(hotswap flashing).

You have a PM
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on August 27, 2023, 08:34:40 am
Please post it as attachment.
Schematic.pdf and pcb.pdf should be sufficient.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on August 27, 2023, 10:45:47 am
Maybe the resolution will help you
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on August 27, 2023, 07:32:48 pm
Thanks. Its not only about resolution though. Its a clone and who knows if they changed something. Having the "clone specific" source wouldn't be wrong. You never know.

Edit:
When i measure larger caps (100uF) the tester shuts off everytime during detection. It shuts off sometimes with 2.2uF and it works properly on very small caps. What's wrong here? I have enabled colors, symbols, esr and e-values.
Edit2:
Maybe Brown-Out @4.3V? Fuses were set by 'make fuses'.
$ avrdude -c usbasp -P usb -p m328p -B 20 -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0xfc:m

I will try a lower bod.
Edit3:
confirmed, needs lower bod.

m-firm 1.50
gm328a/ay-at 16mhz
Title: Re: $20 LCR ESR Transistor checker project
Post by: vitiv on August 27, 2023, 09:15:38 pm
Schematic.pdf and pcb.pdf
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on August 29, 2023, 06:08:24 pm
Thanks vitiv!

The fixed cap for self-adjustment needs an ADC pin and an I/O pin for the resistor. Therefore it's an option for an ATmega324/644/1284 based tester.
1) No TP_CAP in 'config_328.h'? Isn't the 324 the same as 328?

2) When i just write the flash rom ($ make prog_fw) to keep my 'self-adjustment data' (in EEPROM) i get a 'checksum error' on 'boot screen' and profiles are gone. I'm on #define DATA_FLASH. How can i keep the data after flashing?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on August 29, 2023, 07:53:57 pm
The ATmega324 has more I/O pins than the ATmega328. Keeping the old profile(s) isn't supported when flashing a changed/new firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: siealex on September 03, 2023, 07:44:21 pm
A small bug with the E24 resistor series in 1.50m. This series contains "43", in the firmware it's "42".

Open variables.h and find this declaration:
const uint16_t E24_table[NUM_E24] MEM_TYPE = {100, 110, 120, 130, 150, 160, 180, 200, 220, 240, 270, 300, 330, 360, 390, 420, 470, 510, 560, 620, 680, 750, 820, 910};

Change 420 to 430 in this line, save and rebuild.
Title: Re: $20 LCR ESR Transistor checker project
Post by: majortom on September 04, 2023, 01:31:39 am
To everyone who uses my firmware. You can correctly identify JFET pins by looking at smaller Cg= readings ... Sample measurement in the picture...

Hi Yuriy_K,
I have been having fun playing around compiling and testing the different k-firmware, m-firmware.
I have seen you posted some firmware attachments, with .hex, .eep, and a Makefile in a a few posts.
Where would I find your source repository? I'd like to compile it and try it out as well, on this GM328A that I have.
See if I can get your modifications going.

Thanks,
majortom

Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 04, 2023, 03:20:02 am
Hi majortom,

I do not publish my sources due to their strong difference from the last version of the Karl-Heinz sources. In the sources, the font and formulas for calculating inductance and capacitance have been changed, and many color control commands have been added. All the changes are too long to list. Everything that can be published, you can try suitable for MG328A.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on September 04, 2023, 06:50:01 am
Hi majortom,

the open source idea is interpreted one-sidedly by some people!

Greeting Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 04, 2023, 09:01:43 am
the open source idea is interpreted one-sidedly by some people!
Address these reproaches to Chinese friends who churn out these devices in thousands of pieces and sell them without paying any attention to open source idea! :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 05, 2023, 12:31:53 am
Anything wrong with this self-adjustment setup? It always shows 'Error!' after adjustment (still shows value screen though).
I just have 2 clamps so i've put some shorter solid core cable in TP2. Maybe TP2 cable needs to be same length/type as well?
Cable 1+3 are stranded wire.

Short cables (2x solid core cable) for self-adjustment do work.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 05, 2023, 12:10:51 pm
Please post the values displayed during the self-adjustment. My guess would be that the probe resistance is too high.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 05, 2023, 01:11:50 pm
Short cables (2x solid core cable) for self-adjustment do work.
Such short cables are desirable. Long and thin wires with high internal resistance as well as wires that introduce significant additional capacitance and inductance must not be used with this device!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 05, 2023, 08:40:47 pm
Long and thin wires with high internal resistance as well as wires that introduce significant additional capacitance and inductance must not be used with this device!
So, thick wires are better? I will try 1.5mm² and somewhat shorter then.

Please post the values displayed during the self-adjustment.
I've attached the self-adjustment procedure with the setup shown above.

Is there any documentation for the self-adjustment values beside the source code annotations in 'adjust.c'?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 05, 2023, 09:32:44 pm
At step A6 the capacitance between probes #2 and #3 is 113pF for the first run. The limits are noted in the README:
Code: [Select]
Limits:
- probe resistance   < 1.50 Ohms for two probes in series
- probe capacitance  < 100 pF
- IO pin's internal resistance in low mode (RiL)   < 25 Ohms
- IO pin's internal resistance in high mode (RiH)  < 29 Ohms

Have you measured a film cap (100nF - 3.3µF) three times before running the self-adjustment?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 06, 2023, 10:43:10 pm
Looks like its the PSU (H+H SN1000). I suspect the multi plug interface (its somewhat loose). The device itself shouldn't be that bad. It's a heavy trafo (not a small switching one). With battery everything's fine.

1) When i measure 680Ohm (0.1%) i get (quite stable) 677.5Ohm no matter how its adjusted or with/without cables. 470k (0.1%) shows 469.5k that should be ok i guess.
Can i shift the RL value? There is 'RH_OFFSET' in config.h but no 'RL_OFFSET'.

2) I have a 470uF 63V cap. When testing in normal mode it shows 471uF 0.38Ohm. In 'C-Monitor' it shows 453uF with a slightly higher ESR. Do they have different testing methods?
Title: Re: $20 LCR ESR Transistor checker project
Post by: horo on September 07, 2023, 09:09:05 am
Hi,

If you want to create your own firmware version, choosing the right compiler version can noticeably reduce the code size.
I recently did a comparison of different avr-gcc versions. I took all the versions available for Linux (Debian stable) and compiled a 1.50m (with an identical setup for my AY-AT with 20 MHz xtal).
These are the results:

Code: [Select]
avr-gcc v. 12.1.0
Program:   35988 bytes (109.8% Full)
Data:        269 bytes (13.1% Full)
EEPROM:       22 bytes (2.1% Full)
avr-gcc v. 11.1.0:
Program:   35252 bytes (107.6% Full)
Data:        269 bytes (13.1% Full)
EEPROM:       22 bytes (2.1% Full)
avr-gcc v. 10.1.0
Program:   35196 bytes (107.4% Full)
Data:        251 bytes (12.3% Full)
EEPROM:       22 bytes (2.1% Full)
avr-gcc v. 9.2.0
Program:   35190 bytes (107.4% Full)
Data:        251 bytes (12.3% Full)
EEPROM:       22 bytes (2.1% Full)
avr-gcc v. 9.1.0
Program:   35190 bytes (107.4% Full)
Data:        251 bytes (12.3% Full)
EEPROM:       22 bytes (2.1% Full)
avr-gcc v. 8.3.0
Program:   32546 bytes (99.3% Full)
Data:        251 bytes (12.3% Full)
EEPROM:       22 bytes (2.1% Full)
avr-gcc v. 8.2.0
Program:   32536 bytes (99.3% Full)
Data:        251 bytes (12.3% Full)
EEPROM:       22 bytes (2.1% Full)
avr-gcc v. 8.1.0
Program:   32536 bytes (99.3% Full)
Data:        251 bytes (12.3% Full)
EEPROM:       22 bytes (2.1% Full)
avr-gcc v. 7.3.0 (Arduino-Version)
Program:   32612 bytes (99.5% Full)
Data:        251 bytes (12.3% Full)
EEPROM:       22 bytes (2.1% Full)
avr-gcc v. 5.4.0 (Debian-Stable-Version)
Program:   32742 bytes (99.9% Full)
Data:        251 bytes (12.3% Full)
EEPROM:       22 bytes (2.1% Full)

Based on these results, I set 8.3.0 (the last of the major version 8 ) as default.
For later review, I enabled "link-time optimisation" with the compiler switch "-flto", which reduced the code size even further:

Code: [Select]
avr-gcc v. 8.3.0 (my default)
Program:   31770 bytes (97.0% Full)
Data:        244 bytes (11.9% Full)
EEPROM:       22 bytes (2.1% Full)

avr-gcc v. 7.3.0 (Arduino-Version)
Program:   31810 bytes (97.1% Full)
Data:        244 bytes (11.9% Full)
EEPROM:       22 bytes (2.1% Full)

avr-gcc v. 5.4.0 (Debian-Stable-Version)
Program:   32096 bytes (97.9% Full)
Data:        244 bytes (11.9% Full)
EEPROM:       22 bytes (2.1% Full)


Martin
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2023, 12:04:47 pm
1) When i measure 680Ohm (0.1%) i get (quite stable) 677.5Ohm no matter how its adjusted or with/without cables. 470k (0.1%) shows 469.5k that should be ok i guess.
Can i shift the RL value? There is 'RH_OFFSET' in config.h but no 'RL_OFFSET'.

You could try to adjust R_LOW.

2) I have a 470uF 63V cap. When testing in normal mode it shows 471uF 0.38Ohm. In 'C-Monitor' it shows 453uF with a slightly higher ESR. Do they have different testing methods?

No, both use the same measurement functions. Different probes?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 07, 2023, 01:55:57 pm
Same probes. ZIF socket shows same behavior. Tried different power supplies and different caps. Testing resistors is ok.

'Default Test' vs. 'C-Monitor':
1063uF <> 1016uF
463uF <> 444uF
103uF <> 100uF
222nF <> 222nF

The first two measurements of 'C-Monitor' are higher then the following. I have 'hold' values enabled. Maybe the test cycles are too fast?
Not sure if relevant, i have MCP1702 installed with Vref and 2.2k still in place (but disabled in config.h).

Can someone confirm or falsify this behavior?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 07, 2023, 02:43:29 pm
Same probes. ZIF socket shows same behavior. Tried different power supplies and different caps.
Madires, I have the same effect on my clones, but I didn't pay much attention to it.
I made 2 short videos so you can better understand what I'm talking about. I measure the same capacitance 1000uFx10V on ZIF pins 1-3. In the RLC monitor mode, the tester first shows the same capacitance value as in normal testing, but then the result decreases jump. I don't know what is the reason for this behaviour?
https://drive.google.com/file/d/1DSnLMSiL0VmlU29ebRCczFxiez6BJ08C/view?usp=sharing
https://drive.google.com/file/d/1lwazwLodpxfv2d3wuUisQfvdH8jAHm17/view?usp=sharing
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2023, 03:54:15 pm
Does that happen only for electrolytic caps?
Title: Re: $20 LCR ESR Transistor checker project
Post by: ledtester on September 07, 2023, 03:59:21 pm
If you want to create your own firmware version, choosing the right compiler version can noticeably reduce the code size.
...

This is rather incredible! Do you have any idea of what's going on?

Could you post the assembly output from the 8.3 and 12.1 compilers? I would be interested in comparing the two.

See this link for generating an assembly listing interleaved with source:

https://stackoverflow.com/a/1289907
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 07, 2023, 04:14:53 pm
Does that happen only for electrolytic caps?
Yes, only on electrolytic capacitors, I didn't notice it on other families.

I recently did a comparison of different avr-gcc versions. I took all the versions available for Linux (Debian stable) and compiled a 1.50m (with an identical setup for my AY-AT with 20 MHz xtal).
Can you show your settings file for the config.h clone - I'm interested to compare the size of the firmware that will be with my compiler on Windows?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 07, 2023, 05:54:00 pm
Could be dielectric absorption as the polarity stays the same for all measurements in the C monitor (and C measurement in the LCR monitor).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 07, 2023, 06:13:43 pm
madires,hm... but then we should see exactly the same effect on a k-firmware clone if we measure the same capacitance first on pins 1-2 and then on pins 1-3, on which the monitor mode is automatically turned on? But I do not observe such an effect, or am I wrong? This effect does not bother me much, since I know that electrolytic capacitors can have a large deviation from the nominal capacity. But it was just interesting to understand why. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: prashk20 on September 08, 2023, 04:52:15 am
Hello!

I pulled in the 1.50m firmware and ran it on my Arduino Uno. Most of the functions work well except a specific range of resistors. Schematics is mostly based on AY-AT clone.

Before I go on about the issue, I want to thank everyone who is building this amazing instrument. Thank you! :)

Now the problem. I know Arduino Uno and Component Tester on a breadboard is not the best accuracy, but I get error of under 1% on most resistors, except a range where it gives 50% error.
Correct Readings of Resistors within 1%: 220, 330, 470, 1k, 2.2k, 220k, 470k, 1M.
[attach=1] [attach=3] [attach=4]
Incorrect Readings of Resistors: 10 as 5, 100 as 50, 4.7k as 14k, 10k as 4.2k, 22k as 9.9k, 47k as 21.5k, 100k as 44k.
 [attach=2]

I am using 1% resistors as of now and not required 0.1%. I'm not sure if this is the issue because 220 is read correctly but not 100 and 2.2k is correct. 200K is correct but 100K is read as 44K.
This issue is not specific to a set of probe pins. The issue is only with a range of resistors, while another range is read correctly, I wonder what the mistake here might be.

The self adjustment doesn't seem to work. After shorting the probes, it calculates Ri+-, etc., and on next click gives an error. [attach=5]
And the LEDs are not working. (Update: got LEDs working)
Any ideas?

[attachimg=6]

Attached are pictures.
Makefile and config modifications and output is here: https://github.com/pk17r/Transistortester-Warehouse/tree/prash/ComponentTester-1.50m_Arduino_Uno
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 08, 2023, 09:15:12 am
madires,hm... but then we should see exactly the same effect on a k-firmware clone if we measure the same capacitance first on pins 1-2 and then on pins 1-3, on which the monitor mode is automatically turned on? But I do not observe such an effect, or am I wrong? This effect does not bother me much, since I know that electrolytic capacitors can have a large deviation from the nominal capacity. But it was just interesting to understand why. :)

That asks for some further investigation.

Update:
The issue can happen when the electrolytic cap creates a negative voltage in respect to the measurement polarity. Karl-Heinz has solved this in the k-firmware by using a voltage divider to shift the reference point to about 140 mV which allows to also measure a small negative voltage. Both firmwares measure the cap's unloaded voltage after discharging the cap to get the zero offset.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 08, 2023, 09:23:36 am
The self adjustment doesn't seem to work. After shorting the probes, it calculates Ri+-, etc., and on next click gives an error.

Please post the values displayed during the self-adjustment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on September 08, 2023, 10:39:39 am
Any ideas?
Hello!

  For your circuit to work correctly, you need to modify ARDUINO_UNO. Replace the 1000 pF capacitor and cut the trace to input 5 of the op amp, marked with an X.
Title: Re: $20 LCR ESR Transistor checker project
Post by: horo on September 08, 2023, 06:11:55 pm

Could you post the assembly output from the 8.3 and 12.1 compilers? I would be interested in comparing the two.

See this link for generating an assembly listing interleaved with source:

https://stackoverflow.com/a/1289907

I get different output formats for 8.3.0 and 12.1.0, the newer version contains the source code while the old version lacks it.
I attached the compiler output of both versions as well as the disasm (which looks similar to the already produced listing lss).
I had to tar both tar.gz archives because the forum doesn't like tar.gz or tgz.

7.3.0:
Code: [Select]
0000338a <MeasureESR>:
    338a: a4 e0        ldi r26, 0x04 ; 4
    338c: b0 e0        ldi r27, 0x00 ; 0
    338e: eb ec        ldi r30, 0xCB ; 203
    3390: f9 e1        ldi r31, 0x19 ; 25
    3392: 0c 94 d6 3e jmp 0x7dac ; 0x7dac <__prologue_saves__>
    3396: 9c 83        std Y+4, r25 ; 0x04
    3398: 8b 83        std Y+3, r24 ; 0x03
    339a: 89 2b        or r24, r25
    339c: 51 f4        brne .+20      ; 0x33b2 <MeasureESR+0x28>
    339e: 2f ef        ldi r18, 0xFF ; 255
    33a0: 3f ef        ldi r19, 0xFF ; 255
    33a2: 3c 83        std Y+4, r19 ; 0x04
    33a4: 2b 83        std Y+3, r18 ; 0x03
    33a6: 8b 81        ldd r24, Y+3 ; 0x03
    33a8: 9c 81        ldd r25, Y+4 ; 0x04
    33aa: 24 96        adiw r28, 0x04 ; 4
    33ac: e2 e1        ldi r30, 0x12 ; 18
    33ae: 0c 94 f2 3e jmp 0x7de4 ; 0x7de4 <__epilogue_restores__>
    33b2: eb 81        ldd r30, Y+3 ; 0x03
    33b4: fc 81        ldd r31, Y+4 ; 0x04
    33b6: 63 81        ldd r22, Z+3 ; 0x03
    33b8: 74 81        ldd r23, Z+4 ; 0x04
    33ba: 85 81        ldd r24, Z+5 ; 0x05
    33bc: 96 81        ldd r25, Z+6 ; 0x06
    33be: a7 ef        ldi r26, 0xF7 ; 247
    33c0: ea 2e        mov r14, r26
    33c2: 0a e0        ldi r16, 0x0A ; 10
    33c4: 10 e0        ldi r17, 0x00 ; 0
    33c6: 20 e0        ldi r18, 0x00 ; 0
    33c8: 30 e0        ldi r19, 0x00 ; 0
    33ca: 42 81        ldd r20, Z+2 ; 0x02
    33cc: 0e 94 a5 11 call 0x234a ; 0x234a <CmpValue>
    33d0: 87 fd        sbrc r24, 7
    33d2: e5 cf        rjmp .-54      ; 0x339e <MeasureESR+0x14>
    33d4: 0e 94 f4 13 call 0x27e8 ; 0x27e8 <DischargeProbes>
    33d8: 80 91 91 01 lds r24, 0x0191 ; 0x800191 <Check>
    33dc: 81 30        cpi r24, 0x01 ; 1
    33de: f9 f2        breq .-66      ; 0x339e <MeasureESR+0x14>
    33e0: eb 81        ldd r30, Y+3 ; 0x03
    33e2: fc 81        ldd r31, Y+4 ; 0x04
    33e4: 11 81        ldd r17, Z+1 ; 0x01
    33e6: 00 81        ld r16, Z
    33e8: 17 b8        out 0x07, r1 ; 7
    33ea: 18 b8        out 0x08, r1 ; 8
    33ec: 14 b8        out 0x04, r1 ; 4
    33ee: 15 b8        out 0x05, r1 ; 5
    33f0: 40 e0        ldi r20, 0x00 ; 0
    33f2: 61 2f        mov r22, r17
    33f4: 80 2f        mov r24, r16
    33f6: 0e 94 b4 10 call 0x2168 ; 0x2168 <UpdateProbes>


12.1.0:
Code: [Select]
00004614 <MeasureESR>:
 *  - ESR in 0.01 Ohm
 *  - UINT16_MAX on any problem
 */

uint16_t MeasureESR(Capacitor_Type *Cap)
{
    4614: a7 e0        ldi r26, 0x07 ; 7
    4616: b0 e0        ldi r27, 0x00 ; 0
    4618: e0 e1        ldi r30, 0x10 ; 16
    461a: f3 e2        ldi r31, 0x23 ; 35
    461c: 0c 94 a4 44 jmp 0x8948 ; 0x8948 <__prologue_saves__>

00004620 <.L1^B33>:
    4620: 8e 83        std Y+6, r24 ; 0x06
    4622: 9f 83        std Y+7, r25 ; 0x07

00004624 <.LVL1075>:
  uint32_t          Sum_1;         /* sum #1 */
  uint32_t          Sum_2;         /* sum #2 */
  uint32_t          Value;

  /* check for a capacitor >= 10nF */
  if ((Cap == NULL) ||
    4624: 2e 81        ldd r18, Y+6 ; 0x06
    4626: 3f 81        ldd r19, Y+7 ; 0x07
    4628: 23 2b        or r18, r19
    462a: 51 f4        brne .+20      ; 0x4640 <.L605>

0000462c <.L607>:
      (CmpValue(Cap->Value, Cap->Scale, 10, -9) < 0)) return ESR;
    462c: 6f ef        ldi r22, 0xFF ; 255
    462e: 7f ef        ldi r23, 0xFF ; 255
    4630: 7a 83        std Y+2, r23 ; 0x02
    4632: 69 83        std Y+1, r22 ; 0x01

00004634 <.L604>:
  Cfg.Ref = ADC_REF_BANDGAP;       /* we've used the bandgap reference */

  DischargeProbes();               /* discharge DUT */

  return ESR;
}
    4634: 89 81        ldd r24, Y+1 ; 0x01
    4636: 9a 81        ldd r25, Y+2 ; 0x02
    4638: 27 96        adiw r28, 0x07 ; 7
    463a: e2 e1        ldi r30, 0x12 ; 18
    463c: 0c 94 c0 44 jmp 0x8980 ; 0x8980 <__epilogue_restores__>

P.S.:
This linker option gives even more space, from 32562 bytes down to 32044 bytes (avr-gcc-8.3.0):
Code: [Select]
LDFLAGS += -Wl,--relax
Title: Re: $20 LCR ESR Transistor checker project
Post by: majortom on September 08, 2023, 10:57:22 pm
I built the aur package for avr-gcc 8.5, and played around this morning to compare to avr-gcc 13.2.0.
My differences weren't nearly as impressive as horo, but using CFLAGS += -flto definitely helped to
squeeze a couple more features in there that wouldn't have otherwise fit.
GCC 13.2 below was prior to adding some features that normally wouldn't have fit, like IR Detector.

Was earlier this AM, and after a long day of work I might have missed a step here in my description.
edit: and saw similar with the linker --relax switch as well.
 
config.h
https://pastebin.com/Zag8JYRk
config_328.h
https://pastebin.com/jsVF55sL

Code: [Select]

avr-gcc (GCC) 8.5.0
AVR Memory Usage
----------------
Device: atmega328

Program:   32920 bytes (100.5% Full)
(.text + .data + .bootloader)

Data:        265 bytes (12.9% Full)
(.data + .bss + .noinit)

EEPROM:      884 bytes (86.3% Full)
(.eeprom)

avr-gcc (GCC) 8.5.0
CFLAGS += -flto
AVR Memory Usage
----------------
Device: atmega328

Program:   32342 bytes (98.7% Full)
(.text + .data + .bootloader)

Data:        263 bytes (12.8% Full)
(.data + .bss + .noinit)

EEPROM:      884 bytes (86.3% Full)
(.eeprom)


avr-gcc (GCC) 13.2.0
AVR Memory Usage
----------------
Device: atmega328

Program:   28926 bytes (88.3% Full)
(.text + .data + .bootloader)

Data:        261 bytes (12.7% Full)
(.data + .bss + .noinit)

EEPROM:      756 bytes (73.8% Full)
(.eeprom)

avr-gcc (GCC) 13.2.0
CFLAGS += -flto
AVR Memory Usage
----------------
Device: atmega328

Program:   28044 bytes (85.6% Full)
(.text + .data + .bootloader)

Data:        260 bytes (12.7% Full)
(.data + .bss + .noinit)

EEPROM:      756 bytes (73.8% Full)
(.eeprom)
Title: Re: $20 LCR ESR Transistor checker project
Post by: prashk20 on September 09, 2023, 12:34:11 am
The self adjustment doesn't seem to work. After shorting the probes, it calculates Ri+-, etc., and on next click gives an error.

Please post the values displayed during the self-adjustment.

The values are:
Ri- 20.0Ohm
Ri+ 22.0Ohm
C0 43pF
R0 0.20Ohm
Vref 1008mV
Vcc 5001mV
AComp -45mV

Next page on click is Error.

I went through your note on Self-Adjustment (Many many thanks for the superb documentation  :-+, I first used a 2.2uF cap several times before doing this.)

I am using Arduino Uno as of now for prototyping, but will use a Atmega1284 chip or a Teensy 4.0 microcontroller (if suitable) for my finished tester.
Title: Re: $20 LCR ESR Transistor checker project
Post by: prashk20 on September 09, 2023, 01:03:22 am
Any ideas?
Hello!

  For your circuit to work correctly, you need to modify ARDUINO_UNO. Replace the 1000 pF capacitor and cut the trace to input 5 of the op amp, marked with an X.

Hello Yuri,
I didn't think mods would be needed for Uno. I first implemented the k firmware for Arduino Uno shield using the posted hex files and that seemed to work fine, so I thought it should work here as well. For my finished tester, I will use an Atmega1084 chip or a Teensy 4.0 microcontroller (if permissible). The Atmega chip pcb should not run into this issue. I'll next prototype the tester with Atmega1084 chip on a breadboard and see the output. Thank you for the solution!
Regards
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 09, 2023, 01:56:53 am
The values are:
Ri- 20.0Ohm
Ri+ 22.0Ohm
C0 43pF
R0 0.20Ohm
Vref 1008mV
Vcc 5001mV
AComp -45mV

Next page on click is Error.
That's only the summary. The test results beforehand are needed. Or check the 'README' yourself for valid ranges. See this (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5045950/#msg5045950) and following post.
Title: Re: $20 LCR ESR Transistor checker project
Post by: prashk20 on September 09, 2023, 10:11:48 am
The values are:
Ri- 20.0Ohm
Ri+ 22.0Ohm
C0 43pF
R0 0.20Ohm
Vref 1008mV
Vcc 5001mV
AComp -45mV

Next page on click is Error.
That's only the summary. The test results beforehand are needed. Or check the 'README' yourself for valid ranges. See this (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5045950/#msg5045950) and following post.

Hello Maniaxx, thank you for the info! It helped!
I found the problem (an embarrassing one), I was not shorting the pins correctly, used disconnected male headers thinking I am shorting the circuit  :palm:

On actually shorting the circuits, it all works well. Thank you!  :-+
Video: https://drive.google.com/file/d/1Lh0MI19b0TE3IFjUfQ6MI-D5P-kdI-x4/view?usp=sharing (https://drive.google.com/file/d/1Lh0MI19b0TE3IFjUfQ6MI-D5P-kdI-x4/view?usp=sharing)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 09, 2023, 10:16:29 am
That list is the currently used adjustment profile. When the self-adjustment succeeds the profile will be updated. On error it won't change. In this case the first four values are the default values. Vref and AComp are already updated by measuring a film cap three times. Vcc is also the default value (no external reference available). It's a bit confusing, it's simply the same function as called by the 'show values' menu item to keep the firmware size small. Maybe it would be better to show the list only on success.
Title: Re: $20 LCR ESR Transistor checker project
Post by: prashk20 on September 09, 2023, 10:18:17 am
Any ideas?
Hello!

  For your circuit to work correctly, you need to modify ARDUINO_UNO. Replace the 1000 pF capacitor and cut the trace to input 5 of the op amp, marked with an X.

Hello Yuri,
Thank you for the info. Using this I actually found the difference on Uno (100nF) vs Component Tester (1nF) circuit. I also found Madires has clearly given instructions for Uno, which I somehow overlooked. I now enabled ADC_LARGE_BUFFER_CAP in config and that makes it all work. Now 10Ohm, 100, 10k, 22k, etc are all read correctly!
Thank you!  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: prashk20 on September 09, 2023, 10:32:57 am
That list is the currently used adjustment profile. When the self-adjustment succeeds the profile will be updated. On error it won't change. In this case the first four values are the default values. Vref and AComp are already updated by measuring a film cap three times. Vcc is also the default value (no external reference available). It's a bit confusing, it's simply the same function as called by the 'show values' menu item to keep the firmware size small. Maybe it would be better to show the list only on success.

Thank you for the explanation Madires. I earlier didn't really connect that measuring a film cap three times before was doing something. I'm new to this project, so some of the info on Readme and the manual, I miss even after reading it. It's a superb project, I'm super impressed!

I bumped onto this project while looking for better implementations of resistor measurement using potential divider. I got tired of using the Multimeter for every measurement. I made one basic resistor measurement program on Uno but that doesn't work well for small resistors or big ones. Maybe because I didn't use port and pin controls but I'll look into that sometime. Right now this is like amazing! And thank you for maintaining a superb documentation on this project! :) :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 09, 2023, 10:38:40 pm
This linker option gives even more space
Nice, indeed. My config on avr-gcc 8.5.0:

32600 bytes (99.5% Full)
32062 bytes (97.8% Full) #CFLAGS += -flto
31522 bytes (96.2% Full) #CFLAGS += -flto / LDFLAGS += -Wl,--relax

I'm wondering though why 'lto' is present but commented out in MAKEFILE. Maybe it doesn't work on Windows compiler?
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on September 10, 2023, 07:53:56 am
This linker option gives even more space
Nice, indeed. My config on avr-gcc 8.5.0:

32600 bytes (99.5% Full)
32062 bytes (97.8% Full) #CFLAGS += -flto
31522 bytes (96.2% Full) #CFLAGS += -flto / LDFLAGS += -Wl,--relax

I'm wondering though why 'lto' is present but commented out in MAKEFILE. Maybe it doesn't work on Windows compiler?

(#CFLAGS += -flto) is working for me in windows 11 x64 and reduce the 1.50m firmware size
I have tried some versions of avr-gcc from version  4.3.3 (included with the last winavr of 2010)  to  version 12.1.0 and i had the best results with version 7.3.0 and binutils: 2.26.20160125, newer versions seems to drop some optimizations but its in my todo list to try every gcc version. With the m_firmware evolving, for the atmega328 with only 32kb we need to find the best compiler version and options to fit as many features as possible.
with the same code i get
Code: [Select]
avr-gcc 7.3.0
Program:   32652 bytes (99.6% Full)
(.text + .data + .bootloader)

avr-gcc 12.1.0  (110.5% Full)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2023, 08:09:47 am
Maniaxx,moimem and everyone, without attaching the config_h and config_328.h settings files to your messages about compilation with different avr-gcc, the information is of little use, since there is no way for other people to compare results on their computers. majortom did the right thing in his message above and attached these files.
AVR-GCC 13.2 showed surprisingly good compilation results but i can't test it on my Windows machine yet. With avr-gcc 8.3.0(flto enabled) and majortom configuration files I get a firmware size of 31740 bytes (96.9%).
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on September 10, 2023, 09:02:31 am
Maniaxx,moimem and everyone, without attaching the config_h and config_328.h settings files to your messages about compilation with different avr-gcc, the information is of little use, since there is no way for other people to compare results on their computers. majortom did the right thing in his message above and attached these files.
AVR-GCC 13.2 showed surprisingly good compilation results but i can't test it on my Windows machine yet. With avr-gcc 8.3.0(flto enabled) and majortom configuration files I get a firmware size of 31740 bytes (96.9%).

avr-gcc 7.3.0 windows11_x64
Code: [Select]
AVR Memory Usage
----------------
Device: atmega328

Program:   32652 bytes (99.6% Full)
(.text + .data + .bootloader)

Data:        260 bytes (12.7% Full)
(.data + .bss + .noinit)

EEPROM:      903 bytes (88.2% Full)
(.eeprom)

avr-gcc 8.3.0
Code: [Select]
AVR Memory Usage
----------------
Device: atmega328

Program:   32662 bytes (99.7% Full)
(.text + .data + .bootloader)

Data:        260 bytes (12.7% Full)
(.data + .bss + .noinit)

EEPROM:      903 bytes (88.2% Full)
(.eeprom)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2023, 09:29:45 am
moimem, with your configuration files i get slightly different results on Windows 10x64.
A more compact size is obtained with avr-gcc 8.3.0.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 10, 2023, 11:04:20 am
32600 bytes (99.5% Full)
32062 bytes (97.8% Full) #CFLAGS += -flto
31522 bytes (96.2% Full) #CFLAGS += -flto / LDFLAGS += -Wl,--relax

I'm wondering though why 'lto' is present but commented out in MAKEFILE. Maybe it doesn't work on Windows compiler?

Because that option isn't supported by all compilers. IIRC, very old avr-gcc versions don't. I'll add a hint about compiler/linker optimizations to the README textfile.

Addendum:
When experimenting with other optimization options not already in the CFLAGS be careful with time critical functions/measurements. We have seen some options screwing up delay loops. A few years back I had to change a few inline asm delays for that reason.
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on September 10, 2023, 01:02:47 pm
moimem, with your configuration files i get slightly different results on Windows 10x64.
A more compact size is obtained with avr-gcc 8.3.0.
interestingly we obtain the exact file size with avr-gcc 8.3.0 (32662 bytes) so its not related to windows version but i have better results with avr-gcc-7.3.0
i have mixed a lot of versions of gcc and binutils and cant tell wich file is responsible of this defference in results, its either we have different gcc7.3.0 files or its related to an other bin called during compilation.
can you try my attached avr-gcc-7.3.0.exe file, and just drop it in place of the 8.3.0 with all other files from gcc 8.3.0 and check the results
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on September 10, 2023, 02:45:09 pm
moimem,404 - Attachment Not Found
reattached here
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2023, 03:39:37 pm
moimem,I tried to compile with your file, but the size of the firmware did not change at all - 99.8%.
Title: Re: $20 LCR ESR Transistor checker project
Post by: horo on September 10, 2023, 05:49:26 pm
These are the results for my AY-AT setup with different options, available at GitHub:
https://github.com/Ho-Ro/ComponentTester/tree/77066735c597e81ee78742bb1c902b6356520e12

Interesting that version 13 is back on small size, almost similar to version 8.

Code: [Select]
avr-gcc v. 13.2.0
Program:   33246 bytes (101.5% Full)
Program:   32524 bytes (99.3% Full) -flto
Program:   32090 bytes (97.9% Full) -flto; -Wl,--relax

avr-gcc v. 12.1.0
Program:   36834 bytes (112.4% Full)
Program:   35592 bytes (108.6% Full) -flto
Program:   35162 bytes (107.3% Full) -flto; -Wl,--relax

avr-gcc v. 8.3.0
Program:   33262 bytes (101.5% Full)
Program:   32562 bytes (99.4% Full) -flto
Program:   32044 bytes (97.8% Full) -flto; -Wl,--relax

avr-gcc v. 7.3.0
Program:   33332 bytes (101.7% Full)
Program:   32588 bytes (99.5% Full) -flto
Program:   32094 bytes (97.9% Full) -flto; -Wl,--relax

avr-gcc v. 5.4.0
Program:   (> 100% Full)
Program:   (> 100% Full) -flto
Program:   32034 bytes (97.8% Full) -flto; -Wl,--relax
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 10, 2023, 06:18:36 pm
Thanks horo!
With your archive, I got a compilation with the same firmware size as yours on avr-gcc 8.3.0.
Perhaps I'll stop at this point with experiments. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on September 10, 2023, 10:35:55 pm
These are the results for my AY-AT setup with different options, available at GitHub:
https://github.com/Ho-Ro/ComponentTester/tree/77066735c597e81ee78742bb1c902b6356520e12

Interesting that version 13 is back on small size, almost similar to version 8.

Code: [Select]
avr-gcc v. 13.2.0
Program:   33246 bytes (101.5% Full)
Program:   32524 bytes (99.3% Full) -flto
Program:   32090 bytes (97.9% Full) -flto; -Wl,--relax

avr-gcc v. 12.1.0
Program:   36834 bytes (112.4% Full)
Program:   35592 bytes (108.6% Full) -flto
Program:   35162 bytes (107.3% Full) -flto; -Wl,--relax

avr-gcc v. 8.3.0
Program:   33262 bytes (101.5% Full)
Program:   32562 bytes (99.4% Full) -flto
Program:   32044 bytes (97.8% Full) -flto; -Wl,--relax

avr-gcc v. 7.3.0
Program:   33332 bytes (101.7% Full)
Program:   32588 bytes (99.5% Full) -flto
Program:   32094 bytes (97.9% Full) -flto; -Wl,--relax

avr-gcc v. 5.4.0
Program:   (> 100% Full)
Program:   (> 100% Full) -flto
Program:   32034 bytes (97.8% Full) -flto; -Wl,--relax

most intersting fact in my opnion is that the best result so far is obtained with avr-gcc-5.4.0 and -flto -wl, --relax flags
confirmed after testing your code in windows and linux

Code: [Select]
Program:   32034 bytes (97.8% Full)
(.text + .data + .bootloader)

Data:        260 bytes (12.7% Full)
(.data + .bss + .noinit)

EEPROM:       22 bytes (2.1% Full)
(.eeprom)
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 11, 2023, 02:41:19 am
But the question is, does this happen because something important is optimized out and newer versions are smart enough to keep it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 11, 2023, 09:10:30 am
most intersting fact in my opnion is that the best result so far is obtained with avr-gcc-5.4.0 and -flto -wl, --relax flags
Code: [Select]
Program:   32034 bytes (97.8% Full)
(.text + .data + .bootloader)

Data:        260 bytes (12.7% Full)
(.data + .bss + .noinit)

EEPROM:       22 bytes (2.1% Full)
(.eeprom)

The funny thing is that when I returned to my old version of the compiler based on avr-gcc 6.3.1, the code turned out to be the most compact. I just added the -wl, --relax flag to -flto on the advice of horo  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 11, 2023, 09:23:23 pm
The 13.2.0 even outperforms the 8.5.0 now so i will go for that. I'd always prefer newer compilers over older ones if near on-par in size.

Code: [Select]
Custom config (--relax, -flto, avr-gcc 13.2.0):
AVR Memory Usage
----------------
Device: atmega328

Program:   31448 bytes (96.0% Full)
(.text + .data + .bootloader)

Data:        270 bytes (13.2% Full)
(.data + .bss + .noinit)

EEPROM:       22 bytes (2.1% Full)
(.eeprom)

Code: [Select]
Custom config (--relax, -flto, avr-gcc 8.5.0):
AVR Memory Usage
----------------
Device: atmega328

Program:   31522 bytes (96.2% Full)
(.text + .data + .bootloader)

Data:        252 bytes (12.3% Full)
(.data + .bss + .noinit)

EEPROM:       22 bytes (2.1% Full)
(.eeprom)
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on September 13, 2023, 07:46:39 am
The 13.2.0 even outperforms the 8.5.0 now so i will go for that. I'd always prefer newer compilers over older ones if near on-par in size.
I installed the 13.2.0 (had to build an archlinux VM) and tried some experiments and its getting a little bit more complicated since its not always a matter of compiler version but it  also depends of the code itself; adding or removing some features of the firmware make mixed final results, but with few bytes difference i prefere the 13.2 too.

Code: [Select]
config-maniaxx (--relax, -flto) avr-gcc 6.3.1
Program:   31526 bytes (96.2% Full)

config-maniaxx (--relax, -flto) avr-gcc 13.2.0
rogram:   31448 bytes (96.0% Full)

config-horo (--relax, -flto) avr-gcc 6.3.1
Program:   31998 bytes (97.7% Full)

config-horo (--relax, -flto) avr-gcc 13.2.0
Program:   32090 bytes (97.9% Full)
Title: Re: $20 LCR ESR Transistor checker project
Post by: JohnC on September 14, 2023, 04:19:58 pm
Help please to fix my old FISH8840  :scared:

Hi everyone, and thanks very much for all your work on these clone testers!

I would like to repair my original FISH8840 "Big Screen", to repay it for many years of faithful service. It's had the "power fix", upgraded LDO, matched resistors, etc but now the screen is stuffed.

It's been in storage for years, however I think that the front polarizer peeled off - anyway, now it has a very strange circular distortion (see attached pics). I tried overlaying a few polarizing sheets but they didn't improve it, so I thought maybe it used a circular polarizer or something?

The screen is 63 x 51mm, with an 18-conductor ribbon. I've attached a photo of the rear of the PCB, and you can see the 6 pin header going down to the main PCB. The SID, SCLK, RS and REST pins go to the LCD, the VCC goes through an LDO, and there's a heap of bypass caps on the other ribbon connections.

I read that it used a ST7565 controller (??), however I have not un-glued the panel to check and there is no markings on the ribbon cable. I tried searching but can't seem to find a matching replacement, nor even a screen with similar ribbon connection.

Do you have any idea what might be wrong with it, and is it repairable? If not, how could I find a replacement screen, even it it's a smaller footprint?

Obviously it'd be easier just to replace the whole gadget, but I thought I'd give you guys a shout out before I retired it permanently. Do you have any ideas or assistance for me?

Cheers, John  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 15, 2023, 10:48:47 am
Most likely fubar. You could search AliExpress for ST7565 and look for one with a matching flat-flex. Another way is to get an ST7565 display meant for Arduino (5V) and wire it up. Or go for the OSHW firmwares (k or m) and use any supported display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on September 15, 2023, 06:24:45 pm
Looks like it may be fixable with what this guy is doing:

https://www.youtube.com/watch?v=laYbjwxz_Ag (https://www.youtube.com/watch?v=laYbjwxz_Ag)

After that, you just replace the polarizer with a good one and you should be good to go.

However, doing all that, even if you have the patience, can result in a shattered display and personal injury, so I can't really recommend the procedure. It would be best to just replace it like madires said.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rfdes on September 18, 2023, 07:34:40 pm

Curious -
I have my unit apart for some upgrades and was wondering if there is any real motivation to move from 8MHz to 16MHz?  My unit is a simple unit using only the 16x2 display and don't know if there is any real benefit to increasing the frequency.

Does anyone have a valid reason to upgrade to 16MHz?
thanks
Jim


Title: Re: $20 LCR ESR Transistor checker project
Post by: JohnC on September 19, 2023, 02:35:14 am
Most likely fubar. You could search AliExpress for ST7565 and look for one with a matching flat-flex. Another way is to get an ST7565 display meant for Arduino (5V) and wire it up. Or go for the OSHW firmwares (k or m) and use any supported display.

Yeah, however it's probably not worth much $$ spent on it. If I cannot repair the screen, I'll just buy another AY-AT which has a more flexible PCB layout for the add-ons I wanted to install.

Looks like it may be fixable with what this guy is doing...

youtube.com > v=laYbjwxz_Ag

[snip]

Thanks heaps! That is EXACTLY the info that I hoped for!  :D

The replacement polarizer sheets are cheap on AliExpress. That video showed a reflective B&W LCD, yet mine is backlit (blue). Do you know if all the polarizers are the same basic thing?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 19, 2023, 06:06:33 am
Does anyone have a valid reason to upgrade to 16MHz?
This question is asked very often by people who do not read the global author’s manual from Karl-Heinz at all, or who simply skim through it without delving into the technical nuances and thoughts that the author, with his enormous work and effort, wanted to convey to you.
If you open the manual dated November 15, 2021 on page 50, you will find this:
"WITH SamplingADC With this option set, the tester make use of the sampling method of ADC
in special cases. By shifting the sampling time of the ADC with increments of 1, 4 or 16
processor clock intervals for repeatable signals fast changes of voltages can be monitored. The
load time of little capacitors below 100pF can be monitored with a resulting resolution of
0.01pF with a 16MHz processor clock."
The increased clock frequency also makes it possible to test various resonators (ceramic and quartz) in k-firmware, and in m-firmware it also allows you to expand the frequency ranges in the generator and frequency meter functions.
You can set the quartz to a frequency of 20MHz, but not all AVR controllers (especially Chinese ones) work stably at this clock frequency.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rfdes on September 19, 2023, 11:18:39 am
Quote
This question is asked very often by people who do not read the global author’s manual from Karl-Heinz at all,


I'm guilty of this.  I'll go back and read his write-up.  I appreciate the response.  I purchased this board years ago when the clones just started hitting the market.  I now see that this project has turned into a massive thread and  need to spend more time sifting through all of the information.
Take care -
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 20, 2023, 10:31:36 pm
@madires:
Can you add a 'hold' function (button press) for 'continuous mode' so we have time to write down values? On problematic PCBs (covered in collophonium) the continuous mode is better/faster. Generally, i prefer auto-hold mode though.

@all:
What 'test equipment' do you guys use with the tester? I currently use 3x 40cm cables with clamps and some additional solid wires for manually picking/clamping in-circuit. I'm wondering if i should create an interface for my banana-plug DMM equipment, especially the full-size tip pickers might come in handy at times.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 21, 2023, 06:41:18 am
I currently use 3x 40cm cables with clamps and some additional solid wires for manually picking/clamping in-circuit.
I already told you earlier that it is undesirable to use such long conductors with this device!
Despite the apparent simplicity of the circuit design, this tester is a very sensitive device that responds to any change in inductance and capacitance at its test contacts. Even if you save the parameters of your long conductors in profile, you cannot hope that if you change their position in your hands, these values ​​​​will not change much. And these values will vary greatly, I assure you. This will lead to distorted measurement results. External testing probes should not be longer than 10-15cm and have very good contact as well as minimal inductance and internal resistance. As an example, I can give this photo from the Karl-Heinz manual. Did I make it clear for you?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 21, 2023, 10:50:03 am
I cannot confirm that. I do in-curcuit testing (under worst conditions, touching contacts etc) and it works without problems. Even capacitors are not fluctuating in relevant ranges or differ significantly compared to in-socket testing. Tbh, i couldn't even notice any difference at all and results are astonishingly good but i haven't checked all circumstances. The only things that didn't work (expectingly) so far were DB3 DIACS (with 30V breakover).

It works for me and I'm curious what works for you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 21, 2023, 11:16:43 am
Maniaxx, you can make conductors of at least 1 meter in length, no one will forbid you to do this. Use it for your health if it suits you.
But the physical principles of operation of the device and its features have not been canceled. My advice mostly applies to k-firmware users with the SamplingADC option enabled
and for other people who want to learn more. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 21, 2023, 01:42:50 pm
It depends on your use case. Its neglectable e.g. for high capacitance or most semi-conductor function testing. I've had good experiences in uF and even nF ranges. pF is probably unreliable indeed. Be aware what you're doing and you should be good to go.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 21, 2023, 02:29:30 pm
I've had good experiences in uF and even nF ranges.
Do you have the same experience in measuring small amounts of microHenry range inductance with such long probes?
I do not use this tester for in-circuit measurements for several reasons and have written about this before. I still think that it is intended for testing only demounted parts and does not have sufficient protection for the test ports in order to examine in-circuit without fear! The protection in the form of the SRV05 assembly and the 6V8 suppressor looks very unreliable and in 99% of cases does not protect the controller’s measuring ports in any way. For in-circuit measurements, I have more specialized devices and instruments with good protection.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 21, 2023, 10:39:50 pm
Do you have the same experience in measuring small amounts of microHenry range inductance with such long probes?
I've measured two stator coils (180W motor). The results were 20R, 40.62mH for both. I'm not sure if these are sane values at all but the fact that these values were nearly identical for both was sufficient for me to believe they were not blown up. The cables were surely repositioned/curled/pushed/stretched/etc between testings.

does not have sufficient protection for the test ports in order to examine in-circuit without fear!
You measure unpowered of course (especially on AC circuits). And yes, i agree, in-circuit testing is unreliable in many ways. But for NPN/PNPs, Triacs and even many resistors and caps (that reflect target values) its simply a huge time saver. If in doubt you can still pry them out. I like this way of working. You have to be aware of course that the circuit might be playing tricks on you indeed.

I'm not an expert. I just expose my personal experiences and will thankfully stand corrected if i'm doing something wrong. So far the cables were not a show-stopper here though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 23, 2023, 01:38:11 pm
@madires:
Can you add a 'hold' function (button press) for 'continuous mode' so we have time to write down values? On problematic PCBs (covered in collophonium) the continuous mode is better/faster. Generally, i prefer auto-hold mode though.

In continuous mode a short button press will skip any delay. Two short button presses trigger the main menu, and a long button press will power off the tester. So we would need something else. Any suggestion?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hotnuma on September 24, 2023, 03:22:37 pm
Hi there,

I try to build the 1.50m source code under Linux on an Arduino Uno, I've installed gcc-avr avr-libc and avrdude.
Building the code works fine but when I try to "make upload" I have the following error :

Code: [Select]
avrdude warning: verification mismatch
        device 0x32 != input 0x00 at addr 0x0000 (error)
avrdude error: verification mismatch

The command was :

Code: [Select]
avrdude -c arduino -P /dev/ttyACM0 -p m328p -D -b 115200 -U flash:w:./ComponentTester.hex:a -U eeprom:w:./ComponentTester.eep:a
It seems that uploading the hex file works but uploading the eep file fails.

Also I'm not sure which pins I should use with a SSD1306 I2C :

Code: [Select]
#define I2C_SDA          PD0            /* port pin used for SDA */
#define I2C_SCL          PD1            /* port pin used for SCL */

If I understand correctly, PD0, PD1 are used for the UART interface on an Arduino Uno.

Any help would be greatly appreciated. Thanks in advance.

*** Edit : Apparently it's not possible to upload an eep file to an Arduino Uno without an external programmer :

https://forum.arduino.cc/t/avrdude-pretents-to-be-able-to-upload-into-eeprom-but-it-cant/461846

I'll have to try with an Arduino Pro Mini then :P
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 25, 2023, 10:27:55 am
Also I'm not sure which pins I should use with a SSD1306 I2C :

Code: [Select]
#define I2C_SDA          PD0            /* port pin used for SDA */
#define I2C_SCL          PD1            /* port pin used for SCL */

If I understand correctly, PD0, PD1 are used for the UART interface on an Arduino Uno.

Yep, they go to the USB2serial converter. Try two unused pins and change the pin/port configuration accordingly. And don't forget the external pull-up resistors for I2C.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 26, 2023, 09:35:31 am
In continuous mode a short button press will skip any delay. Two short button presses trigger the main menu, and a long button press will power off the tester. So we would need something else. Any suggestion?
What about this:
- Add an option in 'config.h' to enable 'short press' for pause/freeze so rotary controller users can have both functions (short press=pause and rotate right=skip).
One-button device users can also use this (but obviously lack 'rotate right'). They could decide to pick a short auto-continue time or keep the old behavior.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 26, 2023, 09:44:42 am
@madires:
Can you add a 'hold' function (button press) for 'continuous mode' so we have time to write down values? On problematic PCBs (covered in collophonium) the continuous mode is better/faster. Generally, i prefer auto-hold mode though.

I don't understand, what is the point of adding such an option?
If you need to examine the measurement data in detail, use the AUTO-HOLD mode.
If there is not enough time to review the results in continuous mode, simply increase the pause in the setting config.h
#define CYCLE_DELAY   
Why reinvent the wheel and the bicycle?  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 26, 2023, 04:44:10 pm
What about this:
- Add an option in 'config.h' to enable 'short press' for pause/freeze so rotary controller users can have both functions (short press=pause and rotate right=skip).
One-button device users can also use this (but obviously lack 'rotate right'). They could decide to pick a short auto-continue time or keep the old behavior.

Implementing that would require to change/check all TestKey() calls which is a ton of work. And it would also increase the firmware to some extend. Not very motivating.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Maniaxx on September 26, 2023, 05:14:53 pm
Another option would be an 'auto-hold on success' where 'success' is true by either a found semiconductor or predefined threshold (lowcut) for caps (>30pF) and R (>30 Ohm). That would cover the idle range (impact) when holding cables.
Title: Re: $20 LCR ESR Transistor checker project
Post by: hotnuma on September 27, 2023, 01:54:11 pm
And don't forget the external pull-up resistors for I2C.

Thanks a lot @madires, I managed to upload the hex and eep to an Arduino Pro Mini 5V 16 MHz.

Now I have a weird behavior, when I try to test a 1µF cap between 2-3, the device finds most of the time non existing caps with large values such as 89 µF 144 ohms between 1-3 or 949 µF 144 ohms between 1-2 etc... and sometimes it finds the right value among wrong ones, for example 1090 nF 0.87 ohms which is the correct reading.

I enabled ADC_LARGE_BUFFER_CAP for resistors but other than that I don't know what I can do.

Thanks in advance.  :P
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 27, 2023, 02:26:35 pm
That's a common issue when powering the tester with an SMPSU. Please try a linear PSU. The essential settings for Arduino based testers are listed in the Clones File.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on September 27, 2023, 02:28:26 pm
Another option would be an 'auto-hold on success' where 'success' is true by either a found semiconductor or predefined threshold (lowcut) for caps (>30pF) and R (>30 Ohm). That would cover the idle range (impact) when holding cables.

That could be feasible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: fpisi on September 27, 2023, 06:03:42 pm
I bought a GM328A tester from AliExpress with Russian language by mistake. I wanted to change its language, so bought another English one and tried to read its flash but was locked. I also bought developer boards with same microchips, so I have spare ones.

I also downloaded Markus Frejek and  Karl-Heinz projects from GitHub and built my own hex, but unfortunately it didn't work.

Tried the hex file from here: https://github.com/robsoncouto/gm328a_rev_eng, but couldn't get it work.

Anyone has a working English flash, hex file for this latest version tester?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on September 27, 2023, 07:10:42 pm
fpisi,try this firmware
Title: Re: $20 LCR ESR Transistor checker project
Post by: lezginka_kabardinka on September 27, 2023, 11:45:04 pm
Hi friends.

Like to change 'fake' Chinese IC part for genuine "Mega328P U-TH" on device "LCR-T4" (Unit with USB-C port, as seen since silicon downfall)...  = possible?

Thank. u

/update/: Image of downfalled item attach.
Title: Re: $20 LCR ESR Transistor checker project
Post by: lezginka_kabardinka on September 28, 2023, 06:51:31 am
CIyf pstèuri š″h′èfitèu, âl″ytènyg″èrè âfèš″uašèhèmrèkIè zèfèdèu k″al″fy. Ak″ylrè zèhèšIykI g″uazèrè âIèš″y, zyr zym zèk″oš zèhašІè azfagu dèl″èu zèfyŝytynhè fae?

Problem to understand? I speak from Adyghe, sorry have bad English, Circassia! : https://www.youtube.com/watch?v=LJsDPpg-Ikk (https://www.youtube.com/watch?v=LJsDPpg-Ikk)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on September 28, 2023, 11:37:45 am
Like to change 'fake' Chinese IC part for genuine "Mega328P U-TH" on device "LCR-T4"   = possible?
See these posts:
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4762751/#msg4762751 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4762751/#msg4762751)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4745147/#msg4745147 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4745147/#msg4745147)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4742351/#msg4742351 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4742351/#msg4742351)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Stinger on October 01, 2023, 03:27:43 pm
Hi,

Can i flash these LCR-T4 V2.68 clone with CH341a USB programmer ?

(https://www.makerfabs.com/image/cache/makerfabs/LCR-T4%2012864LCD%20ESR%20SCR%20Meter%20Transistor%20Tester/LCR-T4%2012864LCD%20ESR%20SCR%20Meter%20Transistor%20Tester_1-1000x750.JPG)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 02, 2023, 09:46:06 am
Yes, if your CH341a USB programmer supports ISP.
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on October 02, 2023, 12:00:25 pm
I bought a GM328A tester from AliExpress ...
Anyone has a working English flash, hex file for this latest version tester?
I also bought one of these "new version" (https://www.aliexpress.com/item/1005003678038543.html) of GM328A to add to my collection (my TEA is severe...). If the FW posted by indiman doesn't fit, I can try to make a backup of mine, which is in English, if it's not protected.

Also, @indiman, I see this version is not in your table of clones; if you want to include it and need more details, I'd be happy to contribute. It seems genuine 328P for <14€, and I bought it also because, form the photos in the ad, it seemed to have a DC/DC converter that I thought was for zener measurement (but I think it's not) and something that seemed a prescaler for frequency (also think it's not, but up to now I haven't analised it too much).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Circlotron on October 02, 2023, 08:53:17 pm
Haven’t read the whole thread, it’s a bit long. Got one of these things yesterday and every electrolytic cap I measure it shows ESR as zero ohms. Am I doing something wrong or are some of these testers a bit dodgy?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2023, 09:54:20 am
Have you done the self-adjustment?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Circlotron on October 03, 2023, 11:24:14 am
Have you done the self-adjustment?
No. It did not come with any instructions. Where could I find these?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2023, 12:46:48 pm
Short-circuiting all three testpins should trigger the self-adjustment. I don't know if there's a manual for the T4 clone, but please see Karl-Heinz' documentation for the k-firmware (https://github.com/kubi48/TransistorTester-documentation).
Title: Re: $20 LCR ESR Transistor checker project
Post by: LeWidget on October 03, 2023, 02:38:12 pm
Hi all. I was looking to get one of these testers but tossing up between the TC1 & T7. Which one is more useful, reliable, easier to repair if something goes wrong ?

https://www.aliexpress.com/item/1005005237553083.html?spm=a2g0o.productlist.main.3.3fc517ecauDpV2&algo_pvid=f153996f-afd1-4412-bd4a-b646f44233fb&algo_exp_id=f153996f-afd1-4412-bd4a-b646f44233fb-1&pdp_npi=4%40dis%21AUD%2154.17%2119.51%21%21%2133.88%21%21%402103228816963420811975338e03f6%2112000032317691182%21sea%21AU%211614096062%21&curPageLogUid=GZo8cWxUPCuz (https://www.aliexpress.com/item/1005005237553083.html?spm=a2g0o.productlist.main.3.3fc517ecauDpV2&algo_pvid=f153996f-afd1-4412-bd4a-b646f44233fb&algo_exp_id=f153996f-afd1-4412-bd4a-b646f44233fb-1&pdp_npi=4%40dis%21AUD%2154.17%2119.51%21%21%2133.88%21%21%402103228816963420811975338e03f6%2112000032317691182%21sea%21AU%211614096062%21&curPageLogUid=GZo8cWxUPCuz)

https://www.aliexpress.com/item/1005005430295628.html?spm=a2g0o.productlist.main.1.3fc517ecauDpV2&algo_pvid=f153996f-afd1-4412-bd4a-b646f44233fb&algo_exp_id=f153996f-afd1-4412-bd4a-b646f44233fb-0&pdp_npi=4%40dis%21AUD%2142.75%2121.37%21%21%21195.72%21%21%402103228816963420811975338e03f6%2112000033040265575%21sea%21AU%211614096062%21&curPageLogUid=7Wh4HQxFGkdT (https://www.aliexpress.com/item/1005005430295628.html?spm=a2g0o.productlist.main.1.3fc517ecauDpV2&algo_pvid=f153996f-afd1-4412-bd4a-b646f44233fb&algo_exp_id=f153996f-afd1-4412-bd4a-b646f44233fb-0&pdp_npi=4%40dis%21AUD%2142.75%2121.37%21%21%21195.72%21%21%402103228816963420811975338e03f6%2112000033040265575%21sea%21AU%211614096062%21&curPageLogUid=7Wh4HQxFGkdT)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2023, 02:58:44 pm
Make sure to choose a clone with a genuine ATmega. Currently many clones are sold with APT32F172K8T6 or LGT8F328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: LeWidget on October 03, 2023, 05:40:55 pm
Make sure to choose a clone with a genuine ATmega. Currently many clones are sold with APT32F172K8T6 or LGT8F328.

How do you find that out? Reading the description of the products does't mention anything about what chip they come with :/
Title: Re: $20 LCR ESR Transistor checker project
Post by: lezginka_kabardinka on October 03, 2023, 06:19:44 pm
Make sure to choose a clone with a genuine ATmega. Currently many clones are sold with APT32F172K8T6 or LGT8F328.

You make it sound like "a choice"  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 03, 2023, 06:36:31 pm
How do you find that out? Reading the description of the products does't mention anything about what chip they come with :/

It's a lottery at the moment, but there are some hints:

Quote
We have seen popular clones sold in multiple variants with genuine ATmegas and
alternative MCUs, some even with fake ATmega markings. When buying a clone it
can be hard to identify the MCU. Some hints:
- MCU in DIP is usually an genuine ATmega.
- APT32F172K8T6 has different power pins:
  - 32-LQFP/QFN: 18=Vss, 19=Vdd (ATmega328 32-TQFP: 5=Gnd, 4=Vcc)
- APT32F172K8T6 uses SWD port for ISP:
  - 5 pins: Vdd, Vcc, F_SDAT, F_SCLK, F_RST
- Testers with APT32F172K8T6 often lack a quartz crystal.
- LGT8F328 has slightly different pins:
  - QFP32L: 21=PE2/SWD (ATmega328 32-TQFP: 21=Gnd)
- LGT8F328 uses SWD port for ISP:
  - 5 pins: Gnd, Vcc, SWD, SWC, Reset
- Clone variants with an genuine ATmega are usually about EUR/US$ 5 more
  expensive than the variant with a different MCU.

Your best bet is to look for an DIP ATmega or to build a tester yourself.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on October 03, 2023, 07:21:09 pm
I think the slightly more expensive here (https://www.aliexpress.com/item/1005003678038543.html) could be "genuine".
The version called "English Language" (DIP), not the "New English Version".
It's hard to tell with the versions with a case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: LeWidget on October 04, 2023, 06:47:49 am
Thanks for the info :). Q: what does DIP mean ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on October 04, 2023, 06:52:07 am
Thanks for the info :). Q: what does DIP mean ?
https://en.wikipedia.org/wiki/Dual_in-line_package
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on October 04, 2023, 12:32:22 pm
Your best bet is to look for an DIP ATmega or to build a tester yourself.

Prefably socketed in case you fry your chip with a charged capacitor. |O


Title: Re: $20 LCR ESR Transistor checker project
Post by: TA2AWX on October 07, 2023, 08:49:36 pm
Now, this is an interesting video, I timestamped it to the point about counterfeits, but the whole thing is a good watch.

https://youtu.be/wjEI6d8MEJE?si=YFvrNjc8KSCe9m3H&t=546
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 08, 2023, 10:10:54 am
Interestingly, TheElectroBench said in his video that later versions of the LCR-TC2 support around 15 IR RC protocols. What a coincidence! ;D It would be nice if the Chinese clone manufacturers would adhere to the m-firmware's open source license.
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on October 08, 2023, 06:16:36 pm
I think the slightly more expensive here (https://www.aliexpress.com/item/1005003678038543.html) could be "genuine".
The version called "English Language" (DIP), not the "New English Version".
It's hard to tell with the versions with a case.
As I said here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5090326/#msg5090326), I also bought one of these in the "New English Version" with the MCU in TQFP-32 package; I've checked the pinout according to madires' tips here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5092647/#msg5092647) and it seems to be a genuine Atmega. The ICSP pads also go to the correct pins according to ATmega328p's pinout (https://www.ultralibrarian.com/2023/03/16/atmega328p-pinout-architecture-and-application-ulc).

Still haven't tried to read the FW, though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Ariamella on October 08, 2023, 07:16:26 pm
Is there a version of this with an STM32 chip or something along those lines? STM32 MCUs are significantly cheaper nowadays...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 09, 2023, 10:01:07 am
The Transistortester needs a 5V MCU to keep the circuit simple.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Lazarus42 on October 14, 2023, 10:47:40 am
Hey everyone, how's stuff?
Well, an LCR-T4 ESR has just arrived. After much trolling around I plumped for the  one in the photos.
As a bit of a noob I had no idea of the can of worms I was opening. This thread has been fascinating and a steep learning curve for me as I'm just starting out with electronics.
I'm also starting RC slope soaring, I bought the glider after I ended up on two prosthetic legs as incentive to get up & outside.
I thought that apart from being interested in both they seem to dovetail together.
So! how'd I do? Does anyone recognise the beasty that just arrived?
I haven't turned it on yet as my rechargeable 9V battery is not putting out 9V even at full charge, 8.2V isn't in spec and I've read in here that accuracy is sensitive to voltage.
Thanks for this thread, it's been interesting, funny and quite a bit of "Oh bu**er!
Keep safe all,
Lazarus 😎☮️
Edit: Aargh! Just realised, no crystal! ☹️
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 14, 2023, 12:24:35 pm
Yep, fake 328. A genuine 32pin TQFP ATmega328 would have pin 21 (Gnd) connected to ground and pin 20 (AREF) to a 1nF cap. Don't worry too much about the battery's voltage as long as it's above 7V.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Lazarus42 on October 14, 2023, 02:51:11 pm
Thank you! That's eased the pain a little 😃
I'm on the hunt for a manual at the mo and acrylic case on the way.
Onwards and upwards!

Laz😎
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on October 14, 2023, 04:35:13 pm
Still haven't tried to read the FW, though.
I tried to read it today but was protected.... It comes with 1.12K
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on October 16, 2023, 06:00:20 am
Prefably socketed in case you fry your chip with a charged capacitor. |O

The testers with DIP28 sockets can best be seen from the back of the board if shown by the seller.
and this version can also be easily converted to Mega644 using an adapter and upgrade to the latest firmware!

https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/msg4890983/#msg4890983
Title: Re: $20 LCR ESR Transistor checker project
Post by: Lazarus42 on October 16, 2023, 07:14:28 pm
Well, that's the end of that then! I sat down with the LCR-T4, a fresh 9V battery, three legs snipped off of a circuit under construction soldered together and a handful of components to calibrate it and see what it can do.
I peeled off the masking tape they ship it with only to find the Etch-a-Sketch Screen Blight you see below! It's a new one on me. Have you seen a mark like this before? It looks almost 3D, it has depth to it as you change your viewing angle.
Anyway, I attached the battery, shorted it out with the three legs and... Nothing! Removed the short, nothing again. Checked the battery, battery's good.
What a let down!
The supplier has refunded me so I suppose I'm a battery clip and a zif socket up. I'll check what I can with a multimeter, you never know.
Back to reading the thread & searching for obscure, backwater suppliers with new old stock I suppose 🤔
Thanks for the help, I'll pop back up if I find a proper looking unit. 🤞😎☮️
Title: Re: $20 LCR ESR Transistor checker project
Post by: snapper on October 16, 2023, 07:38:56 pm
Definitely the new variant of the C..... Virus, I would quickly package it well and send it to the hazardous waste  :-DD
Title: Re: $20 LCR ESR Transistor checker project
Post by: Lazarus42 on October 16, 2023, 08:22:26 pm
Definitely the new variant of the C..... Virus, I would quickly package it well and send it to the hazardous waste  :-DD

Strange, everything's been fine up to n... Aaaaargh! 😱
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on October 17, 2023, 04:15:23 pm
fpisi,try this firmware
Tested in my GM328A tester "Nev version" (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5090326/#msg5090326) and it works OK, so genuine mega 328Pcconfirmed. It came with 1.12K protected, so I couldn't make a backup (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5113119/#msg5113119) of the original FW. I think I remember the original FW had different options in the menu, but I'm not sure.

Now I'll try to upgrade it to 16 MHz, as I did with the rest of my units
Title: Re: $20 LCR ESR Transistor checker project
Post by: acerquax on October 18, 2023, 10:56:56 am
Hi threat,

I wrote my problems in the transistor-tester fix threat
the desire from indman is to swing over in this threat
so voila  ;D

In some words,

blew up my T7 tester,
replaced the atmega32x to atmega644
built up your transistor replacement U4.

What happens
The tester starts with the introduction menue
<<<Component Tester>>>
<<<LCR-TC1 v1.43m>>>
then it is displayed for a short time
Testing....
Bat 3.9V      VCC 4.98V
then >>>switching off

When I push the button
enable goes high (Pin3) ;
PD1 (Pin7) goes low;
PD2(Pin8) always High
as long as I see the introduction menue

Thats it...  :horse:

I haven't manipulated the fuses until now.
Via microscope I could check the pinning of the 644, all good! :-//

It seems to be having no powersupply for 644 via PD2  |O
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 18, 2023, 11:10:22 am
acerquax,I will repeat my question here, which you did not answer.
What programmer and software do you use to flash the ATMega644 firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on October 18, 2023, 06:00:07 pm
I have used my old TL 866 CS MiniPRO now from XGecu and the software coming with it, to program an ATMEGA 644.
The successor to the TL 866 CS will probably also do. See compatibility list in each case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: acerquax on October 18, 2023, 06:30:04 pm
I checked it with several softwares

AVR Burn-o-mat
and
myAVR Prog tool

My programmer worked always perfect in different projects! (Arduino,esp32...)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 19, 2023, 07:28:30 am
acerquax, It was not out of curiosity that I asked you a question about the programmer and the software that you use.
For the AVR Burn-o-mat shell, you need to set and program the fuses state exactly as I showed in the screenshots below. Only after you have done everything as I showed - program the fuses and verify and read them to make sure that they are installed correctly - can you move on.

P.S The sequence of screenshots that were attached to the message does not match, but I think you can figure out the settings without any problems. Start by setting the Expert mode. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: acerquax on October 19, 2023, 08:35:24 am

I am a bit further.. :palm:
Flashed the fuses as suggested

Tester starts ok, but toggles between
Testing.....
Bat=3,98V     Vcc=4,98V
and
  Battery?
2 4593 mV

with some DUT

Testing.....
Bat=3,98V     Vcc=4,98V
and
 Battery?
1 3673 mV
   :-BROKE


Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 19, 2023, 08:40:27 am
Remove diode assembly DZ2 temporarily and turn the tester on again.
Title: Re: $20 LCR ESR Transistor checker project
Post by: acerquax on October 19, 2023, 10:53:25 am
 :palm:...oh man,
......after some trial and error attempts I noticed that in the battery?-modus
and
3 times pushing the start button
a select menue appears..afterwards one time pushing I can chance the issue
so I guess it works now!
Many thx for your patient indman :clap:
My next idea .....I will study your schematics , maybe I adapt an encoder switch or something like that. 

 :-+ :-+

P.S.: I let the diode assembly as it is?!!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 19, 2023, 11:17:48 am
:palm:...oh man,
......after some trial and error attempts I noticed that in the battery?-modus
and
3 times pushing the start button
P.S.: I let the diode assembly as it is?!!

To be honest, I didn’t understand anything from your last message? Could you explain in a simpler way after what actions did your tester start working?
I don’t understand why you need to press the Test button 3 times? Have you read the madires manual on how to work correctly with m-firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: acerquax on October 20, 2023, 03:44:51 pm
Where do I find the manual? Thx

I guess a small video would be better than 1000 words!!  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 20, 2023, 04:12:27 pm
https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation/German or see the README.de file in the source archive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on October 20, 2023, 04:38:05 pm
Where do I find the manual? Thx

I guess a small video would be better than 1000 words!!  ;D

Not in this specific case.
This is one of the best - if not the best - manual I have ever seen.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 20, 2023, 04:44:22 pm
Not in this specific case.
This is one of the best - if not the best - manual I have ever seen.
You're a little ahead of me! These are the words I wanted adress to acerquax :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: acerquax on October 21, 2023, 03:06:19 pm
Hi mates,

So,  I have to realize, that the tester doesn't detect any DUT neither transistors nor any other device
after switching on the tester and>>> Testing.... appears.
 It swings after a short periode of further time to>>>Battery?
I have read the manuals and could find out that  all other features specified in the manuals are working!! :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 22, 2023, 10:02:59 am
It swings after a short periode of further time to>>>Battery?

Have you tried with the SRV05-4 removed?
Title: Re: $20 LCR ESR Transistor checker project
Post by: acerquax on October 22, 2023, 03:38:29 pm
 :palm:
Oh.......... I had no schematic beside me , so DZ2 and SRV05-4 means the same... :-DD |O
I will give this a try..  ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: acerquax on October 22, 2023, 09:09:39 pm
 It works perfect now....thx a lot mates :-+ :-+ :-+ :clap:
Title: Re: $20 LCR ESR Transistor checker project
Post by: acerquax on October 26, 2023, 06:02:34 am
Hi,
what is the difference between "k" and "m" versions for the tester sw?
Where could I find the latest hex/eep versions for the t7 tester? Is it the 1.43m version?
Thx for ideas.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 26, 2023, 07:09:38 am
Hi,
what is the difference between "k" and "m" versions for the tester sw?
Where could I find the latest hex/eep versions for the t7 tester?

You probably didn't read the Madires manual carefully?
It details the main differences between m-firmware and k-firmware.
Also in this manual there are links to sources where you can find the materials and firmware you need.
The best way to get the version you want is to build the firmware yourself, so you can customize the options you like and need. All it takes is some effort to learn how to compile. Even a child can do it. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on October 26, 2023, 03:02:57 pm
Anyone know of a source to buy a legit Atmel tester in the form of a T1, T2, T7... I like the convenience of the package but have never found one that's not fake, and I've opened quite a few!
Title: Re: $20 LCR ESR Transistor checker project
Post by: xfint34 on October 26, 2023, 08:20:43 pm
What about the GM328A DIP version with the acrylic case?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on October 27, 2023, 04:50:05 am
Well, my request was:

Anyone know of a source to buy a legit Atmel tester in the form of a T1, T2, T7... I like the convenience of the package...

The GM328A DIP version with the acrylic case is not what i'm looking for...
Title: Re: $20 LCR ESR Transistor checker project
Post by: luciano on October 27, 2023, 04:48:39 pm
Hello, what are the problems if I have a tester with a fake (or not Atmega) CPU ? Do they work not good ? Or there is no bad effect ?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on October 27, 2023, 05:40:12 pm
You can't program an OSHW firmware and some measurements are subpar.

Edit: Some also lack the self-adjustment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Fuzzy Star on October 28, 2023, 09:22:44 am
Hello, what are the problems if I have a tester with a fake (or not Atmega) CPU ? Do they work not good ? Or there is no bad effect ?

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4741682/#msg4741682 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4741682/#msg4741682)

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4762751/#msg4762751 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4762751/#msg4762751)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on October 28, 2023, 09:54:32 am
Hello, what are the problems if I have a tester with a fake (or not Atmega) CPU ? Do they work not good ? Or there is no bad effect ?

I have a TC1 with the APT32F172K8T6 and it works quite OK for most components.
Here (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4764980/#msg4764980) I had made some tests.
You can find it 2 posts below this link target (Reply #8323):

For some reason the actual link target is not working.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on October 28, 2023, 04:07:27 pm
Aldo22 Because you misspelled the post number in your link. It should look like this  ;)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4765046/#msg4765046 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4765046/#msg4765046)
I intentionally took another target because the direct link (yours too) just doesn't work (at least not for me).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 28, 2023, 04:13:53 pm
Yes, that's right, there was some kind of glitch in the messaging system. I've noticed this before.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mentholflash on October 30, 2023, 06:37:46 am
Hi all
I have one of the original clones ver 2.2 2012/11/26 atmega128 the same as pic 1 but i have the 2 caps between the lcd headers and a 8m crystal like a mashup of the 2 pics
I am looking to upgrade as much as possible
I have installed an atmega328(duino lilypad) and bought a rotary encoder
I also want to check in circuit esr
Can anyone point me in the direction of upgrade steps with adding encoder and the best firmware to use and steps to be taken
Thanks look forward to your replies
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 30, 2023, 07:45:20 am
mentholflash, I have attached the firmware for your clone below. You will find the encoder connection and programming flash method in the complete manual from Karl-Heinz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mentholflash on October 30, 2023, 08:27:00 am
Thank you for your speedy responce
I did read the encoder part but pd1 and pd3 are not connected at my lcd is it best to just solder to the ic or is there a better way to solder connections.
Thanks again
ps also looking to get a different screen would you know which is best for this device and would it benefit me to put a 1200 crystal just cause i have 1
cheers
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on October 30, 2023, 08:36:01 am
I did read the encoder part but pd1 and pd3 are not connected at my lcd is it best to just solder to the ic or is there a better way to solder connections.
Solder to the ic.

ps also looking to get a different screen would you know which is best for this device and would it benefit me to put a 1200 crystal just cause i have 1.
You can connect to the device any display with a controller that is supported by the firmware authors, but you will also have to update the firmware for the new display. You can only put quartz from the 8,16,20 MHz range into a clone.
Other frequencies are not suitable! All this is explained in detail in the manual.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mentholflash on October 30, 2023, 10:33:40 am
Thank you
Title: Re: $20 LCR ESR Transistor checker project
Post by: u666sa on November 02, 2023, 11:27:26 pm
If anyone looking for clone on real atmel 324

https://aliexpress.ru/item/1005002448100326.html (https://aliexpress.ru/item/1005002448100326.html)

 :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: uboot on November 03, 2023, 09:23:44 pm
Anyone know of a source to buy a legit Atmel tester in the form of a T1, T2, T7... I like the convenience of the package but have never found one that's not fake, and I've opened quite a few!
It seems that the Joy-IT LCR T7 (https://joy-it.net/de/products/JT-LCR-T7) always has a legit Atmega. It can be bought - in Germany at least - from different shops like Reichelt, ELV, Pollin, and Conrad. Some of them ship to other countries.

I just bought one and it has an Atmega324PA and usual ingredients like STC15L104W, TL431, LM7805, Boost Converter, IR Detector, but a slightly different PCB layout than what I have found elsewhere about the Joy-IT LCR T7, e.g. https://arnowelzel.de/m-tester

[attach=1] [attach=2]


But I could not get OSHW firmware to work with it yet  :-//

Following the instructions in the Clones document of v1.50m, I have updated the STC15 uC with https://github.com/atar-axis/tc1-u4 and set up the Makefile, config.h, and config_644.h but after flashing the device does not boot. (Lipo battery was disconnected of course during all ISP operations)

Now, when I press the test button, the LCD will power up with backlight and blank black screen and as soon as I release the button it switches back off. Nothing else will happen.

If you look at the pictures, C3 right above the Atmega is missing, but it was like that from the beginning and the device did work before with stock firmware, but I didn't like it - it even did not calculate ESR...


Any ideas for a noob like me on where to start with trouble shooting?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 04, 2023, 06:39:30 am
Any ideas for a noob like me on where to start with trouble shooting?
Yes, there are ideas. You have a clone model from FNIRSI, and these guys could have changed the connection between the display and the controller. You also need to trace which controller ports the U8 pins are connected to?
Therefore, first you need to draw this schematic and compare it with the classic one for this clone. Your further actions will depend on this. Good luck.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on November 04, 2023, 11:30:57 am
... @uboot, your board is very similar to the TC1 and T7, but J7 is missing.

In the appendix is the circuit of TC1/T7. This way you can better determine the port occupancy.

Good luck

Greetings Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on November 04, 2023, 12:08:12 pm
Didn't read the forum for a long time and have found different GCC comparision in accordance to fw size.
I have downloaded some gcc versions, including official one from microchip and have created a small script. Here is result for my particular case. So, sometimes the oldest one is the best one...
Code: [Select]
Trying system's avr-gcc [avr-gcc (GCC) 5.4.0] ... 28360 bytes
Trying avr-gcc-10.1.0-x64-linux [avr-gcc (GCC) 10.1.0] ... 30742 bytes
Trying avr-gcc-11.1.0-x64-linux [avr-gcc (GCC) 11.1.0] ... 30612 bytes
Trying avr-gcc-12.1.0-x64-linux [avr-gcc (GCC) 12.1.0] ... 31036 bytes
Trying avr-gcc-13.2.0-fc [avr-gcc (Fedora 13.2.0-1.fc38) 13.2.0] ... 28754 bytes
Trying avr-gcc-7.3.0-arduino [avr-gcc (GCC) 7.3.0] ... 28458 bytes
Trying avr-gcc-7.3.0-x64-linux [avr-gcc (GCC) 7.3.0] ... 28460 bytes
Trying avr-gcc-8.1.0-x64-linux [avr-gcc (GCC) 8.1.0] ... 28550 bytes
Trying avr-gcc-8.2.0-x64-linux [avr-gcc (GCC) 8.2.0] ... 28550 bytes
Trying avr-gcc-8.3.0-x64-linux [avr-gcc (GCC) 8.3.0] ... 28562 bytes
Trying avr-gcc-9.1.0-x64-linux [avr-gcc (GCC) 9.1.0] ... 30588 bytes
Trying avr-gcc-9.2.0-x64-linux [avr-gcc (GCC) 9.2.0] ... 30580 bytes
Trying avr8-gnu-toolchain-linux_x86_64-microchip [avr-gcc (AVR_8_bit_GNU_Toolchain_3.7.0_1796) 7.3.0] ... 28458 bytes
Title: Re: $20 LCR ESR Transistor checker project
Post by: uboot on November 04, 2023, 12:32:30 pm
@vklimk how about compiler optimizations and switches? I wonder if latest avr-gcc can be tweaked to get same low sizes as past versions just because there are different defaults being used.

I guess you already you use -Os everywhere, right? But there is more.

Here is a nice article that you might translate with Google: https://www.mikrocontroller.net/articles/AVR-GCC-Codeoptimierung (https://www.mikrocontroller.net/articles/AVR-GCC-Codeoptimierung)

For instance, -fno-jump-tables will reduce my current v1.50m build from 32072 to 32016 bytes.

And with a combination of CFLAGS += -ffunction-sections and LDFLAGS += -Wl,--gc-sections I was able to reduce that even further down to 31892 bytes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: vklimk on November 04, 2023, 05:27:07 pm
For instance, -fno-jump-tables will reduce my current v1.50m build from 32072 to 32016 bytes.

And with a combination of CFLAGS += -ffunction-sections and LDFLAGS += -Wl,--gc-sections I was able to reduce that even further down to 31892 bytes.
In my case it changes to the following if I add all these 3 options:
Code: [Select]
Trying system's avr-gcc [avr-gcc (GCC) 5.4.0] ... 28330 bytes
Trying avr-gcc-10.1.0-x64-linux [avr-gcc (GCC) 10.1.0] ... 30706 bytes
Trying avr-gcc-11.1.0-x64-linux [avr-gcc (GCC) 11.1.0] ... 30574 bytes
Trying avr-gcc-12.1.0-x64-linux [avr-gcc (GCC) 12.1.0] ... 30984 bytes
Trying avr-gcc-13.2.0-fc [avr-gcc (Fedora 13.2.0-1.fc38) 13.2.0] ... 28720 bytes
Trying avr-gcc-7.3.0-arduino [avr-gcc (GCC) 7.3.0] ... 28428 bytes
Trying avr-gcc-7.3.0-x64-linux [avr-gcc (GCC) 7.3.0] ... 28430 bytes
Trying avr-gcc-8.1.0-x64-linux [avr-gcc (GCC) 8.1.0] ... 28522 bytes
Trying avr-gcc-8.2.0-x64-linux [avr-gcc (GCC) 8.2.0] ... 28522 bytes
Trying avr-gcc-8.3.0-x64-linux [avr-gcc (GCC) 8.3.0] ... 28530 bytes
Trying avr-gcc-9.1.0-x64-linux [avr-gcc (GCC) 9.1.0] ... 30494 bytes
Trying avr-gcc-9.2.0-x64-linux [avr-gcc (GCC) 9.2.0] ... 30486 bytes
Trying avr8-gnu-toolchain-linux_x86_64-microchip [avr-gcc (AVR_8_bit_GNU_Toolchain_3.7.0_1796) 7.3.0] ... 28428 bytes
And I have the same result if I don't use CFLAGS += -ffunction-sections and LDFLAGS += -Wl,--gc-sections.
gcc 5.4.0 produces the smallest fw again. In my specific case.

My options are the following at the moment:
Code: [Select]
# compiler flags
CC = avr-gcc
CPP = avr-g++
CFLAGS = -mmcu=${MCU} -Wall -I. -Ibitmaps
CFLAGS += -DF_CPU=${FREQ}000000UL
CFLAGS += -DOSC_STARTUP=${OSC_STARTUP}
CFLAGS += -gdwarf-2 -std=gnu99 -Os -mcall-prologues
CFLAGS += -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
CFLAGS += -flto -fno-jump-tables
CFLAGS += -MD -MP -MT $(*F).o -MF dep/$(@F).d

# linker flags
LDFLAGS = -g -mmcu=${MCU} -Wl,--relax,-Map=${NAME}.map

PS. After reading that article you suggested I have added more options which allowed to save a little more space: -fno-inline-small-functions -fno-split-wide-types -fno-move-loop-invariants -fno-tree-loop-optimize -mstrict-X
And result is the following:
Code: [Select]
Trying system's avr-gcc [avr-gcc (GCC) 5.4.0] ... 28072 bytes
Trying avr-gcc-10.1.0-x64-linux [avr-gcc (GCC) 10.1.0] ... 30176 bytes
Trying avr-gcc-11.1.0-x64-linux [avr-gcc (GCC) 11.1.0] ... 30188 bytes
Trying avr-gcc-12.1.0-x64-linux [avr-gcc (GCC) 12.1.0] ... 30486 bytes
Trying avr-gcc-13.2.0-fc [avr-gcc (Fedora 13.2.0-1.fc38) 13.2.0] ... 28250 bytes
Trying avr-gcc-7.3.0-arduino [avr-gcc (GCC) 7.3.0] ... 28226 bytes
Trying avr-gcc-7.3.0-x64-linux [avr-gcc (GCC) 7.3.0] ... 28228 bytes
Trying avr-gcc-8.1.0-x64-linux [avr-gcc (GCC) 8.1.0] ... 28330 bytes
Trying avr-gcc-8.2.0-x64-linux [avr-gcc (GCC) 8.2.0] ... 28330 bytes
Trying avr-gcc-8.3.0-x64-linux [avr-gcc (GCC) 8.3.0] ... 28350 bytes
Trying avr-gcc-9.1.0-x64-linux [avr-gcc (GCC) 9.1.0] ... 30150 bytes
Trying avr-gcc-9.2.0-x64-linux [avr-gcc (GCC) 9.2.0] ... 30142 bytes
Trying avr8-gnu-toolchain-linux_x86_64-microchip [avr-gcc (AVR_8_bit_GNU_Toolchain_3.7.0_1796) 7.3.0] ... 28226 bytes
Options:
Code: [Select]
# compiler flags
CC = avr-gcc
CPP = avr-g++
CFLAGS = -mmcu=${MCU} -Wall -I. -Ibitmaps
CFLAGS += -DF_CPU=${FREQ}000000UL
CFLAGS += -DOSC_STARTUP=${OSC_STARTUP}
CFLAGS += -gdwarf-2 -std=gnu99 -Os -mcall-prologues -fno-inline-small-functions -fno-split-wide-types -fno-move-loop-invariants -fno-tree-loop-optimize -mstrict-X
CFLAGS += -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
CFLAGS += -flto -fno-jump-tables
CFLAGS += -MD -MP -MT $(*F).o -MF dep/$(@F).d

# linker flags
LDFLAGS = -g -mmcu=${MCU} -Wl,--relax,-Map=${NAME}.map
avr-gcc 5.4.0 is the winner again.
And again - it is my particular code configuration. It may happen that for other code configuration another avr-gcc version will win.
Title: Re: $20 LCR ESR Transistor checker project
Post by: uboot on November 04, 2023, 07:59:30 pm
@Obelix2007: compared to the schematics you posted, I found the following differences:

PB5 -> MOSI+LCD_SDA instead of MOSI+LCD_DC
PB6 -> only MISO instead of MISO+LDC_SDA
PB2 -> Collector of some 1AM NPN Transistor (MMBT3904LT1?) marked Q2 instead of NC
PB3 -> LCD_DC instead of NC

Connections to Test socket and STC15 look similar.

I then changed LCD pin assignment in the config file accordingly and reprogrammed it, but still same behavior.

So I suspect there is some difference in the power-up circuitry and I wonder if I will even need different firmware for the STC15 :-/


Emitter of Q2/1AM is grounded, Base is going to the Test button and when the latter is pressed, it's reaching out to R8+R30 on the very bottom left of the PCB. R30 goes to the Collector of another 1AM transistor (marked Q3) nearby, Emitter again grounded and Base going to C11+C5 wich go in parallel to GND.

R8 goes to what looks like Gate of an A1SHB/HM2301B  P-Channel Mosfet marked Q1 whose Drain is going to Pin4 of B628/U6 and U77.

Well, and the Test button has no direct connection to the STC15  ::)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 05, 2023, 08:12:29 am
uboot,As I suspected earlier, the Chinese guys from FNIRSI tried very hard to prevent you from easily updating the firmware to OSHW. Tell them a big thank you. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on November 05, 2023, 08:29:50 am
I recently bought a TC2 HaoQi from AliExpress and the PCB was silkscreened with "T7-PLUS V2.0". The tester is utter crap as the measurements are very inconsistent, erroneous and all over the place  >:(
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 05, 2023, 12:40:16 pm
Well, and the Test button has no direct connection to the STC15  ::)

Have you tried the settings for 'Multifunction Tester T7 with ATmega328' listed in the Clones file? Your tester looks very similar to that variant.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 05, 2023, 12:46:35 pm
I recently bought a TC2 HaoQi from AliExpress and the PCB was silkscreened with "T7-PLUS V2.0". The tester is utter crap as the measurements are very inconsistent, erroneous and all over the place  >:(

Could be one with an alternative MCU. A few pages back I posted some hints about detecting those (or see top of the Clones file in the source archive).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on November 06, 2023, 08:45:14 am
The MCU is a no-brand-no markings variant. I'll take some photos and will post them here...
Title: Re: $20 LCR ESR Transistor checker project
Post by: LeWidget on November 08, 2023, 06:40:54 pm
Still looking to get one of these testers. Are there any versions &/or sources that are good & accurate straight out of the box or do all need some sort of modding?
Title: Re: $20 LCR ESR Transistor checker project
Post by: maxmatteo on November 08, 2023, 06:46:15 pm
i went with the Bside Esr02 pro, has a real atmel inside and works great...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on November 08, 2023, 07:29:54 pm
i went with the Bside Esr02 pro, has a real atmel inside and works great...
Where did you buy it?
Title: Re: $20 LCR ESR Transistor checker project
Post by: maxmatteo on November 08, 2023, 08:51:05 pm
aliexpress
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pygmalion on November 13, 2023, 09:59:56 pm
Hello!  I am late to the party, so I hope you won't mind.

I want to have LCR ESR tester of my own and I just don't want to buy a fake one.  On the other hand, I have substantial experience with Arduino and even created my own projects with SMD ATmega328, with PCB designed in KiCAD and ordered at JCLPCB.

Would you recommend me making my own?
Which DIY project / ATmega328 sketch would you recommend?
Is the sketch for LCR ESR testers still being actively updated and is the latest code better than the one used in Chinese clones?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2023, 11:13:09 am
Yes! The best Transistortester is the one you make yourself.;) Please see https://github.com/madires/Transistortester-Warehouse/tree/master/Hardware for a starting point. There are two OSHW firmwares (k and m). You will find the m-firmware in the same repo and the latest k-firmware at https://github.com/kubi48/TransistorTester-source. Most clones are based on the k-firmware. Both OSHW firmwares are way better in functionality, but have less fancy graphics.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pygmalion on November 14, 2023, 01:03:00 pm
Explanation of difference between m and k firmware is supposed to be in your README file, which I cannot find...  Can you help me with this?

I am absolutely interested in making my own, because I want to have the latest firmware all the time.  Is building one yourself much more expensive that buying a good quality finished Chinese clone?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2023, 01:40:02 pm
The README file is part of the m-firmware's source archive. For the list of differences look for section "What's different?" (around line 157). Building your own tester is probably a bit more expensive (it's mainly the ATmega, display and PCB). But you'll get a genuine ATmega and all the hardware options you want to have.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pygmalion on November 14, 2023, 01:56:33 pm
I just realised that I can also make a stripboard version ;D. In this case, I already have most of the components on hand (DIP ATmega and 16x2 display included).  But I did not find a nice KiCAD design. I might be tempted to make my own if there is none available.

BTW, in my experience the most expensive part in my projects is shipping from JLCPCB |O... everything else can be sourced locally or at AliExpress for a negligible shipping.

I also discovered that you guys use diylc, a great free alternative for Fritzing program, which is no longer free |O. I have always drawn my stripboard projects in LateX/TikZ :palm:.

Even after reading the FAQ, the content of github is still confusing. There are 14 files in the hardware folder and you can not tell what each file is about unless you open it (and sometimes you do not know even after you open it :o).

I would assume that all hardware projects can use both firmwares, right? On the other hand, the FAQ mentions using a different, more powerful chip than the ATmega328. I only have ATmega328s at home (both DIP and SMD), but I would be willing to buy another chip if it would improve functionality. I am a bit confused on this point.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 14, 2023, 02:02:48 pm
On the other hand, the FAQ mentions using a different, more powerful chip than the ATmega382.
Not ATMega 382 but ATMega328
Read the user manual again carefully and you will find a list of supported controllers as well as answers to almost all future questions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pygmalion on November 14, 2023, 02:12:33 pm
Not ATMega 382 but ATMega328

Corrected.  By the way, "m" is lower case  :P

Read the user manual again carefully and you will find a list of supported controllers.

That is not the point. The point is that using another controller with more than 32kB of memory makes sense only if there is firmware that utilises that extra memory. If there isn't any, even just in plan, it does not make sense to use anything more advanced than the ATmega328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on November 14, 2023, 02:18:21 pm
That is not the point.
This is precisely the point. If you are going to build your own device, then you will have to master the compilation of firmware for it.
If you study the manual more deeply, you will understand that the firmware is compiled for any supported controller, only the set of available plug-in options and settings changes. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pygmalion on November 14, 2023, 03:17:33 pm
That is not the point.
This is precisely the point. If you are going to build your own device, then you will have to master the compilation of firmware for it.
If you study the manual more deeply, you will understand that the firmware is compiled for any supported controller, only the set of available plug-in options and settings changes. ;)

So if I compile with all options then 32k will no longer be enough?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 14, 2023, 03:18:34 pm
I would assume that all hardware projects can use both firmwares, right? On the other hand, the FAQ mentions using a different, more powerful chip than the ATmega328. I only have ATmega328s at home (both DIP and SMD), but I would be willing to buy another chip if it would improve functionality. I am a bit confused on this point.

The basic tester and most options are supported by both OSHW firmwares, a few options only by the m-firmware. Supported MCUs are ATmega328, 324, 644, 1284, 640, 1280 and 2560. The k-firmware supports also older types like the ATmega168.

The point is that using another controller with more than 32kB of memory makes sense only if there is firmware that utilises that extra memory. If there isn't any, even just in plan, it does not make sense to use anything more advanced than the ATmega328.

With multiple additional features enabled the firmware easily exceeds 32kB. So an ATmega644 is the best choice at the moment. Anyway, it depends on which features you need.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pygmalion on November 14, 2023, 04:00:13 pm
OMG. I really appreciate your work, but the learning curve is pretty steep. Someone should create a FAQ for potential builders...

If I understand it correctly, there is no single compile and no single PCB CAD file, because there are zillion different combinations. If they want to build their own device, they have to start from scratch, draw the entire schematic and create the PCB in CAD. And then they might see that their own compile and PCB are later used commercially for Chinese clones...

For me, it's quite doable, but I estimate it would take me (as someone who has neither a job nor formal training in electronics) at least three weeks if I were to focus on just this one project. For one (1) device. I am not sure I want to invest that much time, at least not until I finish my other hobby projects (like overhauling the ZX Spectrum or automating HO switches with DCC...), which will also take months if not years as they are just hobbies. In the meantime, I will just use my DMM and occasionally a signal generator/oscilloscope to measure the more complex things like ESR. Or, more likely, I will just buy a Chinese clone...

PS Can it at least be compiled in the Arduino IDE like the rest of Arduino stuff?
Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on November 14, 2023, 04:57:42 pm
Weeks?! Learning curve? All this simple project requires is a compatible ATMega, a screen and a few resistors to make it work. Great for someone who just learned to solder or for a child. You can throw your first one together on a piece of cardboard within a few minutes. The hardest part is figuring out how to program the MCU, but even that's easy for someone who's got an Arduino, which you clearly do. This is NOT an Arduino project, but it was ported for those who just don't care. Just go to YouTube and watch some videos. People put together these testers with an Arduino and without one within minutes in real time... you can try simply follow what they do. But if you choose to use a standalone MCU it's easier to use the precompiled firmware, which is what you'd probably want to do at first to test things out.

As for an FAQ, there's no need, this project has the best of manuals, find and read it, then RTFM, then consult the manual. It explains everything including how to improve the basic circuit and which displays to use.

And yes, after that you'd probably want to design a variant of your own with a unique PCB created in your choice of software. And take as much time doing it as you need.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pygmalion on November 14, 2023, 06:02:21 pm
I am sorry, I did not make myself clear enough. I could replicate one of those Veroboard projects on github without videos and tutorials in, let's be realistic, a couple of hours. But I just wanted to skip the testing phase and immediately create a "real" device on a "real" PCB and with a 64k IC. Just like these Chinese clones, apart from the 64k IC. And for that I would need the time I specified. So for a "real" device, it's not worth it for me to invest such huge effort to build a slightly better device than the one I can buy ready-made. I am talking about my personal cost-benefit estimate here, which you may not share.  [And since I am afraid the Chinese will send me some rubbish with fake controller, I will end up buying nothing and juggling with my oscilloscope and signal generator forever.  :-//]

As for the information available, I spent several hours reading documents on github to find out that this is not for me. Maybe I am just stupid or maybe this could all be explained in a few words in a document.  I wanted to make a useful suggestion, but you are absolutely free to ignore it.
Title: Re: $20 LCR ESR Transistor checker project
Post by: steveharriss on November 18, 2023, 09:17:55 am
I have only just come across this project having purchased one of the cheap Chinese clones some time ago. It's been a really useful bit of kit to have around. The fact that so many people have taken the time to share their expertise is brilliant.

I took a look at the DevKit-644 posted on GitHub and decided to have the PCB's made up in order that I can make my own AVR Transistor Tester. They are now on their way to me and I am pulling together the parts that I don't have to hand.

I've seen the advice about matching the resistors and I'll bear that in mind when it comes time to build it. I would like a visual reference though to keep me on track. Is there anyone who has previously built this DevKit-644 who would kindly share a picture of the completed PCB with components. TIA  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2023, 11:42:44 am
Please see https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/msg1201483/#msg1201483 (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/msg1201483/#msg1201483).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pygmalion on November 18, 2023, 04:15:42 pm
I took a look at the DevKit-644 posted on GitHub and decided to have the PCB's made up in order that I can make my own AVR Transistor Tester. They are now on their way to me and I am pulling together the parts that I don't have to hand.

After your post, I went looking for the DevKit-644 project and finally found it in the hardware folder :palm:. And after opening it, I found a complete project with KiCAD files. Looks great and may be exactly what I was looking for, especially if I succeed to get it to under 10cmx10cm and half the price of the PCB.

Since this project uses the ATmega644, does this mean that it is the most advanced version of the tester at the moment and that it supports all tester options?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 18, 2023, 05:55:02 pm
Yes and no. ;) That circuit is a basic tester with a few hardware options meant to be used as base for developing and testing new options. If you want to use it as a normal tester please modify the circuit as needed (add a display and more options, remove the relay for the Sampling-ADC's adjustment cap). The main benefits of that ATmega644 tester are more flash, more I/O pins and hardware SPI for driving a display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pygmalion on November 18, 2023, 07:30:16 pm
Yes and no. ;) That circuit is a basic tester with a few hardware options meant to be used as base for developing and testing new options. If you want to use it as a normal tester please modify the circuit as needed (add a display and more options, remove the relay for the Sampling-ADC's adjustment cap). The main benefits of that ATmega644 tester are more flash, more I/O pins and hardware SPI for driving a display.

​I actually love the fact that the PCB does not include a display :-+. This is a modular approach to the tester, everyone uses the same module PCB and then the display is connected to the module bus; different pins are used depending on the display type.  Also, I have half a dozen displays at home, which I used when researching for my display web page (https://www.pinteric.com/displays.html), and I may decide which one to use later 8).

I see that the PCB already contains a Zener test. Is there a list and circuits for other options? ???

Also, instead of the near-obsolete 9V batteries, I would prefer to use 5V power and/or Li-Ion batteries with boost-up to 5V, which would also simplify some of the circuitry. (Possibly even using a cheap Chinese boost-up for the Zener part) Is there a reason to use 9V?

That's what's scares me off, designing the optimal circuit... In comparison, PCB design is a piece of cake.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on November 18, 2023, 08:04:38 pm
this Tester comes with AtMega324 and I removed it and mount the pincompatible AtMega644. [attachimg=1]

Sorry for my bad english.

Greeting Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 19, 2023, 11:34:31 am
I see that the PCB already contains a Zener test. Is there a list and circuits for other options? ???

Please see the documentation of both OSHW firmwares (k and m) and also the hardware directory in the repo.

Also, instead of the near-obsolete 9V batteries, I would prefer to use 5V power and/or Li-Ion batteries with boost-up to 5V, which would also simplify some of the circuitry. (Possibly even using a cheap Chinese boost-up for the Zener part) Is there a reason to use 9V?

No, you just need a stable, clean and precise 5V supply. And don't forget to adapt the power management  to whatever you choose. The tester shown by Obelix2007 comes with a LiPo battery plus boost converter and linear post regulation, for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: steveharriss on November 20, 2023, 11:31:43 am
Really appreciate that. Here's the manufactured PCB's. I have a few spares I can send out for postage. I'm in the UK
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on November 20, 2023, 12:56:57 pm
I can confirm that these (https://www.aliexpress.com/item/1005003678038543.html) come with an ATMEGA328PU (Version "English Language" without "New").
Not particularly fast, but much more accurate than my TC1 with the APT32F172K8T6.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 20, 2023, 02:17:07 pm
That's an AY-AT (aka GM328A) which is still a nice basic tester. And it's supported by both OSHW firmwares (k & m).
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on November 20, 2023, 05:57:58 pm
I can confirm that these (https://www.aliexpress.com/item/1005003678038543.html) come with an ATMEGA328PU (Version "English Language" without "New").
Not particularly fast, but much more accurate than my TC1 with the APT32F172K8T6.
And the "New English Version" of that seller also comes with a genuine ATMEGA328PU, as I confirmed here  (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5118426/#msg5118426), just in QFP package.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Aldo22 on November 21, 2023, 09:42:31 am
That's an AY-AT (aka GM328A) which is still a nice basic tester.
Yes, I've done a few simple tests.
It's pretty accurate for such a cheap device.
Attached:
200Ω (1%) SMD resistor.
1KHz
1.0111 V
Title: Re: $20 LCR ESR Transistor checker project
Post by: mentholflash on November 21, 2023, 10:54:10 am
Really appreciate that. Here's the manufactured PCB's. I have a few spares I can send out for postage. I'm in the UK
Hey mate whereabouts in the uk are you would you consider sending 1 to Australia
cheers
Title: Re: $20 LCR ESR Transistor checker project
Post by: mentholflash on November 21, 2023, 10:58:34 am
Hi all
Can anyone tell me if this is
A. OK
2. Going to work
for adding a rotary encoder to 2013 booster edition
Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: hojnikb on November 21, 2023, 11:29:25 am
Is anyone still porting LGT8F328P to m/k-firmware ?

Or is this it? https://github.com/DurandA/transistor-tester-lgt328p
Title: Re: $20 LCR ESR Transistor checker project
Post by: dirtmover on November 21, 2023, 03:22:28 pm
I recently bought a TC2 HaoQi from AliExpress and the PCB was silkscreened with "T7-PLUS V2.0". The tester is utter crap as the measurements are very inconsistent, erroneous and all over the place  >:(

I fell for that POS as well and am having similar problems. There's some instructions a few months back for swapping out the LGT8F328P for an Atmega328 and switching to open source FW to get it working correctly.

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4804496/#msg4804496 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4804496/#msg4804496)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4899587/#msg4899587 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4899587/#msg4899587)

I've got a couple of Atmega328p in my parts drawer so will give this a try when I get a chance.

Is anyone still porting LGT8F328P to m/k-firmware ?

Or is this it? https://github.com/DurandA/transistor-tester-lgt328p (https://github.com/DurandA/transistor-tester-lgt328p)

That repo looks abandoned since Feb 2021. I think you can safely say that was a pie in the sky attempt that never got off the ground.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 21, 2023, 04:33:41 pm
Is anyone still porting LGT8F328P to m/k-firmware ?

Someone wanted to, but I don't know the current status.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 21, 2023, 04:44:41 pm
Can anyone tell me if this is
A. OK
2. Going to work
for adding a rotary encoder to 2013 booster edition

The resistors seem to be reversed. Please see Karl-Heinz' documentation (https://github.com/kubi48/TransistorTester-documentation) for the rotary encoder option.
Title: Re: $20 LCR ESR Transistor checker project
Post by: DELTA67 on November 28, 2023, 01:03:00 pm
Hi all,
Thanks madires for maintaining this awesome project!!!
How about using an LGT8F328P instead of the ATMEGA328P?
Can the 12bit resolution of the ADC in the LGT improve accuracy?
Is the differential mode, of the said ADC, of any useful application in measurements?
How about the pseudo math coprocessor uDSC, Can it speed some calculations?

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 28, 2023, 03:11:52 pm
We'll stick with the ATmega for the next years for several reasons. e.g. long term availability. If someone likes to port the OSHW firmwares to the LGT8F328P that would be totally fine with us. I have no hands-on experience with the LGT8F328P, so I can't say anything about the impact of its higher resolution ADC. The circuit of the Transistortester is designed for single-ended inputs. Complex real-time calculations aren't done by the firmware to keep the firmware size small. Instead we use tables with pre-calculated values.for those cases.
Title: Re: $20 LCR ESR Transistor checker project
Post by: DELTA67 on November 29, 2023, 09:53:38 am
OK, GREAT thanks anyway.
I want to try using an external ADC (ADS1115) instead of the integrated one. is it mandatory to read many samples then averaging and How to calculate values like "BJT_Level = 2557; " to accommodate the new 15bit resolution ?
Can you, please, add a battery testing function (Li-ion and Lead-acid types) ?
Perhaps this needs extra hardware to measure cranking current for LA batteries for example.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on November 29, 2023, 12:58:32 pm
The oversampling with the ATmega's internal ADC is done to improve the resolution, accuracy and measurement results. Moving to an external ADC won't be easy as you would need to adapt large parts of the firmware. If you want to do that the first step is to understand the firmware. Only then you will be able to determine what you have to change and how. And it will surely increase the firmware size significantly. For battery testing I'd recommend a proper battery tester, expecially for batteries with a high short circuit current. Yes, that involves power electronics, e.g. a bank of MOSFETs to switch the current.
Title: Re: $20 LCR ESR Transistor checker project
Post by: coromonadalix on November 29, 2023, 01:55:26 pm
@delta67

since all the code is / are available  you are free to implement what you want and share your results

this project is made simple to avoid the previously given explanations, adding this or that will change the code and design, and the project price

you are free to adapt whatever mcu you want etc ...   you have more powerful arduino pcb's  teensy's   stm32 arduino compatible stufff you can go up to 24 bits  if you want  loll  any lcd size too

i have one of theses   it work well enough for  my needs

but keep in mind  this is not a professional tool  in any way,  its not a dmm
not a battery load, not a professional  lcr   etc ...

it is a general / simple tool / practical tool 


Title: Re: $20 LCR ESR Transistor checker project
Post by: DELTA67 on November 29, 2023, 05:05:07 pm
@coromonadalix
I know very well this great project and I'm aware of it's limitations. I've built one not just bought a ready made clone.

@ Markus
I've tested (PROTEUS simulation) the ADS1115 with a stripped down version of Frejek's code and it works "pas mal"!
The problem is with the voltage values. For an 1N4148 I've got more than 1V forward voltage.
I've joined the code with simulation file.
NOTE:
- This stripped version can be used as a starting point to study the full code.
- ADS1115 module is very easy to use (code) and to add to the hardware.
- The full code has already the I2C driver needed to communicate with the ADS.
Title: Re: $20 LCR ESR Transistor checker project
Post by: ayubando on December 06, 2023, 08:35:09 pm
Wow. I would surely  loveto have one
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 18, 2023, 12:20:23 pm
Something for long, cold winter evenings:

v1.51m
- Changed GetThirdProbe() into convenience function UpdateProbes2() to reduce firmware size and adapted calls in various other functions (suggested by Viktor Klimkovich).
- Optimized DataStorage() and ManageAdjustmentStorage() to reduce firmware size (thanks to Viktor Klimkovich).
- Added option to slow down bit-bang SPI in case of a high MCU clock rate (SPI_SLOWDOWN, suggested by Viktor Klimkovich).
- Changed calculation of delay loop in IR_Detector() to support MCU overclocking (thanks to Viktor Klimkovich).
- Improved voltage drop algorithm in function LargeCap().
- Function LargeCap() takes now also negative zero offset into account.
- Changed self-adjustment to show the list of adjustment values only on success to prevent any misunderstanding.
- Corrected wrong value in E24 table (reported by siealex@EEVblog).
- POWER_OFF_TIMEOUT applies also to the main menu now (suggested by indman@EEVblog).
- Added French texts (thanks to moimem@EEVblog).
- Updated Brazilian Portuguese texts (thanks to wandows@EEVblog).
- Updated Polish texts #2 (thanks to Jacon@EEVblog).
- Corrected character 'q' in font_8x8_iso8859-2_hf.h (thanks to siealex@EEVblog).
- Updated Russian texts (thanks to indman@EEVblog).
- Updated Spanish texts (thanks to pepe10000@EEVblog).

Please downlaod at:
- https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
- https://github.com/kubi48/TransistorTester-source/tree/master/Markus
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on December 18, 2023, 11:51:58 pm
Thanks madires for the update, here attached my 1.51m builds for LCR-T4 nostripgrid
Title: Re: $20 LCR ESR Transistor checker project
Post by: Brad808 on December 19, 2023, 04:02:32 pm
This thread is great, thanks for all the information and hard work! I spent last weekend replacing the ATmega328p in a bside esr02 (blew it up with a charged cap a long time ago) and programming 1.13k onto it. I have a second esr02 that I bought after the first one blew up and I'm thinking of trying to put the m firmware on that one. Does anyone release a pre-compiled version of the m firmware for the esr02? I did find an old version floating around, but I wasn't sure if anyone maintains new versions anywhere. Thanks
Title: Re: $20 LCR ESR Transistor checker project
Post by: horo on December 19, 2023, 05:49:46 pm
If you want to experiment you can also clone my repo that's a mirror of Markus' source code in git mode.

https://github.com/Ho-Ro/ComponentTester

Here's the branch of my version for the AY-AT with 20 MHz:

https://github.com/Ho-Ro/ComponentTester/tree/AY-AT_20MHz

Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on December 20, 2023, 12:53:31 pm
Something for long, cold winter evenings:
v1.51m
Thank you madires.

There were problems during testing.
With these settings

//#define SW_MONITOR_L          /* just L */
#define SW_MONITOR_RCL        /* R plus L, or C plus ESR */
//#define SW_MONITOR_RL         /* R plus L */

Capacitors are measured unstably at inputs 1-2, 2-3 and are not measured at inputs 1-3.
Hiland M644 16 MHz.
shown in the photo:
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 20, 2023, 01:29:58 pm
I tried your settings with a 16MHz ATmega644 tester but couldn't reproduce what you've seen. Also after running the RCL monitor a 1µF cap measured fine for all probe combinations.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on December 20, 2023, 03:06:57 pm
Here are all the modified files to check my previous post.

If you replace CAP.C with a similar file from 1.50m, then everything works fine ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 21, 2023, 11:18:01 am
Using a smaller cap I'm able to reproduce the issue. And yes, the best solution for now is to take 1.50m's cap.c.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on December 21, 2023, 02:42:17 pm
To fix 1.51m's cap issue edit function LargeCap() in file cap.c. At the beginning of LargeCap() insert
Code: [Select]
  int16_t           U_temp;        /* temporary voltage */

And further down replace
Code: [Select]
    /* consider zero offset */
    if (U_Cap > U_Zero)            /* voltage higher than zero offset */
      U_Cap -= U_Zero;                  /* subtract zero offset */
    else                           /* shouldn't happen but you never know */
      U_Cap = 0;                        /* assume 0V */
with
Code: [Select]
    /* consider zero offset */
    U_temp = (int16_t)U_Cap;       /* explicit type conversion */
    if (U_temp > U_Zero)           /* voltage higher than zero offset */
      U_temp -= U_Zero;                 /* subtract zero offset */
    else                           /* shouldn't happen but you never know */
      U_temp = 0;                       /* assume 0V */
    U_Cap = (uint16_t)U_temp;      /* take result */
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 21, 2023, 03:16:45 pm
madires, thank you! Perhaps it will be easier for someone to replace the old cap.c file with the corrected one.
I've added it below. Right?  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pizzigri on December 25, 2023, 12:22:39 am
In fact, this work has already been implemented for you by the author of the extended ATmega644-1284 tester scheme - dear Nick Lanchak. It is his great contribution to the development of this project that Karl-Heinz mentions in his manual.You can read the full documentation on his device here ;)
https://drive.google.com/folderview?id=0B4yqyYy2Daakfl9DeTBkMEJVTVNwajkzNGtjVi0wcjdMUG5ZODJXa216WFZEZG1ZZE1ud3M&usp=sharing&tid=0B4yqyYy2DaakZzBVU3JDSXB6S1E (https://drive.google.com/folderview?id=0B4yqyYy2Daakfl9DeTBkMEJVTVNwajkzNGtjVi0wcjdMUG5ZODJXa216WFZEZG1ZZE1ud3M&usp=sharing&tid=0B4yqyYy2DaakZzBVU3JDSXB6S1E)
Alternative link
http://vrtp.ru/screenshots/3588_Rev_A0.02C_m1284.zip (http://vrtp.ru/screenshots/3588_Rev_A0.02C_m1284.zip)
Hello Indman,
It took a year - health problems and more.... but, I have managed to find basically all of the parts needed to build Nick's design - except the BFR93A,215 and BFT93,215 transistors  from NXP Semiconductors. Both are out of production, and I cannot find an equivalent. I already tried ebay and two on two, from different vendors, were fakes. Is there a source, or a replacement you - or Nick -  can suggest, that is available i.e. on Mouser?
Thank you so much!
Franco
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on December 25, 2023, 07:09:48 am
Hi pizzigri!
This problem with buying real BFR93A and BFT93 is well known to me.
I made 4 attempts to order these transistors on Aliexpress and only in the last parcel the seller included really high-frequency specimens. In the other 3 cases, they sent me a fake in the form of cheap MOSFETs.
I haven't purchased anything from Mouser, so maybe someone else can help you with this. :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: pizzigri on December 25, 2023, 10:47:42 pm
Wow! Thank you. Would you mind sharing the aliexpress source of these real high frequency parts? In PM also if you want! The way the circuit is designed makes it really difficult to replace these parts.
Franco
Title: Re: $20 LCR ESR Transistor checker project
Post by: Bibbbi on December 26, 2023, 07:13:28 pm
How can I compile the madires Transistor project via PlatformIO/VSCode IDE instead of WinAVR. Are there instructions?
Title: Re: $20 LCR ESR Transistor checker project
Post by: prashk20 on January 01, 2024, 02:34:33 am
Hello!

I have designed a small compact board based on Component Tester project that works using a single 3.7V LiPo battery. I have also added LiPo Charge Boost Protect circuit made by Great Scott with improvements. This combined project serves as Component Tester along with a Battery or USBC powered Power Supply providing 4.5-15V, ~1.5A and Power Monitor in the form factor of an Arduino Uno.

The only thing I have added in the code is a Power Monitor page measuring ADC Voltage of current measured using a Hall Effect Current Measurement IC - TMCS1108A4B and it's adjustment value at 0amps.

Attached are some its pictures.

Blog entry with more pictures, specifications and demonstration video: https://pk17r.wordpress.com/2023/12/18/ultimate-tester-component-tester-lipo-charge-boost-protect/
Project Github, Hex, EEP file: https://github.com/pk17r/Transistortester-Warehouse/tree/prash/ComponentTester-1.50m
Project Schematics, PCB, Boost resistors and E-Fuse resistor calculations, BOM and Gerber Files: https://github.com/pk17r/Transistortester-Warehouse/blob/prash/ComponentTester-1.50m/UltimateTester_PCB.zip

I did this to have the Component Tester project as well as a Power Supply in a small form factor. Thank you to everyone who helped me debug bringing up the Component Tester project on Arduino Uno a few months back, as well as @Madires to maintain the big project!
I am learning PCB design, if you have any feedback on the design or have suggestions on things I could have done differently, please feel free to comment on the blog entry.

Thank you!

Prashant

Title: Re: $20 LCR ESR Transistor checker project
Post by: matt09 on January 03, 2024, 11:56:17 pm
Could someone please post a working link to a current genuine 328 meter on Aliexpress?
I just spent a while searching the reviews in every single TC1 / 7 I could see for a confirmation of a genuine unit, but all I found was confirmation of fake ICs  :-//

Thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on January 04, 2024, 07:01:45 am
This has become a major problem. Even if you get a recommendation, you can never be sure, because things change so fast.
Title: Re: $20 LCR ESR Transistor checker project
Post by: slybunda on January 04, 2024, 02:45:04 pm
Really appreciate that. Here's the manufactured PCB's. I have a few spares I can send out for postage. I'm in the UK

will this check capacitor esr? if so id be up for one board im in West Midlands UK if thats close to you for collection otherwise post is fine thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: slybunda on January 04, 2024, 06:54:47 pm
Anyone built one of these:
https://youtu.be/mogaMWEWWlQ?si=3ij6w7viWwfwyJh3

This looks very simple to do and cheapo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 04, 2024, 07:36:24 pm
will this check capacitor esr?

Yes, if you run one of the two OSHW firmwares (k or m).

Anyone built one of these:
https://youtu.be/mogaMWEWWlQ?si=3ij6w7viWwfwyJh3

This looks very simple to do and cheapo.

Several users have built their Transistortester based on an Arduino (Uno, Nano, Mega). But I'd recommend to go for one of the two OSHW firmwares to get all features. The adapted Arduino sketches are limited in that regard.
Title: Re: $20 LCR ESR Transistor checker project
Post by: slybunda on January 04, 2024, 11:46:09 pm
will this check capacitor esr?

Yes, if you run one of the two OSHW firmwares (k or m).

Anyone built one of these:
https://youtu.be/mogaMWEWWlQ?si=3ij6w7viWwfwyJh3

This looks very simple to do and cheapo.

Several users have built their Transistortester based on an Arduino (Uno, Nano, Mega). But I'd recommend to go for one of the two OSHW firmwares to get all features. The adapted Arduino sketches are limited in that regard.

Is there a link to where to get started on building one of  those oshw ones?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 05, 2024, 11:25:05 am
k-firmware: https://github.com/kubi48/TransistorTester-source
main documentation: https://github.com/kubi48/TransistorTester-documentation
m-firmware and more: https://github.com/madires/Transistortester-Warehouse
Title: Re: $20 LCR ESR Transistor checker project
Post by: jdev99 on January 05, 2024, 01:00:14 pm
1st, thank you to all that contributed to this project. It is amazing. :-+

I noticed something interesting on a  ST7735 display when I un-commented these 2 lines in the config_644.h file:
I wanted to see the effect, thought it would "move" the display to the side and to the bottom by 4 and 2 pixels.

#define LCD_OFFSET_X     4               /* enable x offset of 2 or 4 dots */
#define LCD_OFFSET_Y     2               /* enable y offset of 1 or 2 dots */

The display did not work 100% after this, had some "interference" on 2 sides, and some other odd effects on the displayed contents.
So I just put the // back in-front of the 2 lines, but the display did not return to its previous, good state.

I then did this, and it was good again.

#define LCD_OFFSET_X     0              /* enable x offset of 2 or 4 dots */
#define LCD_OFFSET_Y     0               /* enable y offset of 1 or 2 dots */

Is this the normal way to "reset" these settings?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 05, 2024, 02:16:56 pm
The display did not work 100% after this, had some "interference" on 2 sides, and some other odd effects on the displayed contents.
So I just put the // back in-front of the 2 lines, but the display did not return to its previous, good state.

This means that you did not apply or save changes to the edited rows. Therefore, the firmware compilation chose the previous values.
Or you programmed the old firmware by mistake.
You could try an offset of 2 and 1 pixel respectively for your display.
Title: Re: $20 LCR ESR Transistor checker project
Post by: pizzigri on January 08, 2024, 06:55:12 pm
Karl-Heinz's 1.13K manual covers a Atmega644 schematic, with many add-ons, including a relay based protection - But, no definite PCB design.
Please help...
In fact, this work has already been implemented for you by the author of the extended ATmega644-1284 tester scheme - dear Nick Lanchak. It is his great contribution to the development of this project that Karl-Heinz mentions in his manual.You can read the full documentation on his device here ;)
https://drive.google.com/folderview?id=0B4yqyYy2Daakfl9DeTBkMEJVTVNwajkzNGtjVi0wcjdMUG5ZODJXa216WFZEZG1ZZE1ud3M&usp=sharing&tid=0B4yqyYy2DaakZzBVU3JDSXB6S1E (https://drive.google.com/folderview?id=0B4yqyYy2Daakfl9DeTBkMEJVTVNwajkzNGtjVi0wcjdMUG5ZODJXa216WFZEZG1ZZE1ud3M&usp=sharing&tid=0B4yqyYy2DaakZzBVU3JDSXB6S1E)
Alternative link
http://vrtp.ru/screenshots/3588_Rev_A0.02C_m1284.zip (http://vrtp.ru/screenshots/3588_Rev_A0.02C_m1284.zip)

Dear Indman,
I finally managed to source everything NickL's project needed. The last parts are on their way and hopefully they are real - BFR93A and BFT93.
I will be starting stuffing the board soon. I sourced the LCD specc'd by NickL for the project, but I have a few questions. Is the FW able to drive this obscure LCD, and is it replaceable by a color version?
Also, the PCB silkscreen requires a 8MHz xtal, however it is ambiguous if the mods needed for a 16MHz Xtal are already there or not - the BOM somehow did place a 16MHz part in the order, but I cannot remember if I modified it or that it was in the xls file.
Which FW should I use with the larger memory I have available using a 644 or even a 1284? I have both MCU on hand for the build.

It took a year... and finally i am going to build it! And, the heck - the parts for this build add up to almost 140 Euro. Not complaining, as most parts have a level of accuracy (i.e. 0.1 resistors!) that will undoubtedly reflect in great precision - and here is one more question, there is a resistor (R35) that can go from 15k to 175k - and the value must be "found adjusting", however it is not clear how to find this value. I was actually thinking of replacing it with a 200K SMD trimmer.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 09, 2024, 08:40:32 am
I will be starting stuffing the board soon. I sourced the LCD specc'd by NickL for the project, but I have a few questions. Is the FW able to drive this obscure LCD, and is it replaceable by a color version?
NickL is a very competent, intelligent person and specialist who made a very big contribution to the development of this project, so his tester designs are well thought out and designed, and are also equipped with detailed documentation and proven firmware. Therefore, feel free to repeat what he suggested and everything will work if you do everything correctly.

Also, the PCB silkscreen requires a 8MHz xtal, however it is ambiguous if the mods needed for a 16MHz Xtal are already there or not - the BOM somehow did place a 16MHz part in the order, but I cannot remember if I modified it or that it was in the xls file.
Which FW should I use with the larger memory I have available using a 644 or even a 1284? I have both MCU on hand for the build.
It is better to use 1284, as this will allow you to connect a color display in the future, which requires more memory for all options. With a monochrome display you can leave the crystal at 8MHz, but a color display will require a higher clock speed as well as a hardware SPI connection. If you understand compilation, you can easily assemble your own firmware with the options you need.

Title: Re: $20 LCR ESR Transistor checker project
Post by: ogulpal on January 12, 2024, 06:43:53 pm
Hi, I'm looking for this kind of tester. I've checked the PDF (https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf) that lists all the clones and it looks like the Hiland M644 is a decent option. But the PDF is a few years old and I can't find this particular model anywhere on eBay or Aliexpress.

I liked that it can test Zener diodes above 5V and would have liked it to have external power too.

Are there updated recommendations? If not, what happened to this model and where to find it?

Cheers!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on January 12, 2024, 08:27:51 pm
Be careful. I'seen the transistor tester being advertised as "Hiland M644", whereas the corresonduing pic showed a 328 processor of some sort. The current situation is pretty bad, since you will in advance never know what you will actually get. :palm:
Title: Re: $20 LCR ESR Transistor checker project
Post by: moimem on January 13, 2024, 12:29:09 am
New builds for LCR-T4 NoStripGrid with cap fix
Title: Re: $20 LCR ESR Transistor checker project
Post by: SA on January 13, 2024, 02:40:26 am
Hello

I have put a config of the m firmware here https://gitlab.com/a11059/t7_328_m.git that works on my recenlty purchased T7 with atmega 328 image below.
There's also a schematic in there, it may have some errors/ommisions.

Thankyou Markus.

(Attachment Link)

I am a newbie. I fried my TC-1, looks exactly like your picture with atmega328p DIP ic. The only way to repair it by replacing the atmega328p. I will be thankful if you provide the Hex , Epp and fuses for it......
Title: Re: $20 LCR ESR Transistor checker project
Post by: ogulpal on January 13, 2024, 06:24:49 am
But so what do I even look for? Hiland m644 has no hits on Alibay.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Obelix2007 on January 13, 2024, 01:50:35 pm
... https://de-m.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html

Greeting Horst
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on January 14, 2024, 02:22:35 am
I have an old MK-328 that I bought several years ago. I think I flashed it back then, as when it powers on, it says "GM328" and the "Show Data" menu reports firmware "1.14k".

Attached is a picture of the front of the case (from the net, but mine is exactly the same). Also, a picture of the PCB (again from the net).

It has a real 328P with an 8 MHz crystal. In the upper left corner are several unpopulated pads. Near the center are missing C9, U2, D2 & L1.

Can anyone tell me what the missing components are for? I assume that some may be for zener testing. Is there a full schematic, showing the missing components? Is it worth the trouble adding a rotary encoder and other missing features?

If I hold down the power button, I get a menu with several choices. Short presses cycle through them, and a long press selects one.
Title: Re: $20 LCR ESR Transistor checker project
Post by: coromonadalix on January 14, 2024, 02:59:17 am
mmm maybe was for a rechargeable battery ??  you have diodes and a inductor ...  and the 2 diodes seems to protect against an inverted supply

r22  would be some limiting resistor or can or could blow if over current ?


you would need to dismantle it and try to make a schematic

many teardowns on the web show no populated parts .....
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2024, 09:53:10 am
Can anyone tell me what the missing components are for? I assume that some may be for zener testing. Is there a full schematic, showing the missing components? Is it worth the trouble adding a rotary encoder and other missing features?

Looks like a signal input stage for the frequency counter. A rotary encoder helps with menu functions. And the firmware is a modified k-firmware (the latest k-firmware is 1.13k). If you like to update please see https://github.com/kubi48/TransistorTester-source/tree/master/trunk/mega328_MK-328,
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 14, 2024, 02:25:06 pm
In the upper left corner are several unpopulated pads. Near the center are missing C9, U2, D2 & L1.
U2 is the place to install the same +5V stabilizer as U6, just a slightly smaller form factor.
C9 is an additional capacitor for filtering the +5V output voltage. In some MK-328 models, 47μFx16V is installed in this place. L1 is an inductance for additional filtering of the input voltage to the stabilizer U6 (instead, jumper R14 is now installed). D2 is a protective diode. In general, these additional elements are not needed for this circuit, since it works stably without them.
Connector J5 and the circuit for it are an input signal bufer -  for the frequency counter option (as dear madires answered correctly).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on January 14, 2024, 06:16:14 pm
Hi, I'm looking for this kind of tester. I've checked the PDF (https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf (https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf)) that lists all the clones and it looks like the Hiland M644 is a decent option. But the PDF is a few years old and I can't find this particular model anywhere on eBay or Aliexpress.

I liked that it can test Zener diodes above 5V and would have liked it to have external power too.

Are there updated recommendations? If not, what happened to this model and where to find it?

Cheers!
... https://de-m.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html (https://de-m.banggood.com/Original-Hiland-M644-Transistor-Tester-LCR-Diode-Transistor-Zener-Quartz-Measurement-p-1279042.html)

Greeting Horst
Just adding my $0.02 opinion: the Hiland M644 is not worth $40
It has quite a few design mistakes that reduce the accuracy and usefulness of the device.
But on this note I wonder if any nice DIY projects exists to make a tester based on the Atmega 644 or 1284 chip that still stays true to the original intent of keeping this a simple low cost device?
On the previous page a very advanced SMD version was shown but I'd be more interested in a cut down version.
Maybe the PCB could be designed to both accept through hole and SMD components (or two separate PCB designs).
So far the closest designs I've found are these but I don't know if they have been published?
https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/msg1201483/#msg1201483 (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/msg1201483/#msg1201483)
https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/msg4851821/#msg4851821 (https://www.eevblog.com/forum/testgear/show-us-your-$20-transistor-tester-enclosures-and-mods/msg4851821/#msg4851821)

A cursory Google search also brought up this design, but I could not find the original author of it:
https://oshwlab.com/amilio.spring/ESR-Atmega-644 (https://oshwlab.com/amilio.spring/ESR-Atmega-644)

I think it would be nice if someone competent in PCB design would make a project on Github to make the hardware as accessible as the software is.
I could try myself but I'd probably make the same kind of mistakes that the original Hiland M644 design has as I'm not a PCB designer by trade...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2024, 06:47:04 pm
For the 644/1284 dev kit please see https://github.com/madires/Transistortester-Warehouse/tree/master/Hardware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Per Hansson on January 14, 2024, 07:37:44 pm
Thanks madires! Is the display PCB also available?
I just found a post by snapper on the German forum where he made an updated version of the Hiland M644 PCB.
I'm not sure if he published it anywhere though?
Relevant posts:

https://www.mikrocontroller.net/topic/transistortester-avr?page=32#7511818 (https://www.mikrocontroller.net/topic/transistortester-avr?page=32#7511818)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4886483/#msg4886483 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4886483/#msg4886483)
Title: Re: $20 LCR ESR Transistor checker project
Post by: coromonadalix on January 14, 2024, 07:49:25 pm
same for a mega 2560 ... nothing so far  ...  but code is there ...
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2024, 08:56:42 pm
Is the display PCB also available?

No, it's just a 3.3V LDO and level shifters (74HC4050, 74HCT125).

I just found a post by snapper on the German forum where he made an updated version of the Hiland M644 PCB.
I'm not sure if he published it anywhere though?

AFAIK, he didn't publish the PCB. However, you could ask him for a copy.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 14, 2024, 09:01:20 pm
same for a mega 2560 ... nothing so far  ...  but code is there ...

I'm using an Arduino Mega 2560 clone for testing, especially for displays with an 8-bit parallel bus.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Bibbbi on January 18, 2024, 11:47:24 am
Has anyone successfully managed to compile the madires Transistor project via the IDE Platform VSCode/PlatformIO instead of using the old WinAVR environment?

How does it work?  :-//
Title: Re: $20 LCR ESR Transistor checker project
Post by: jdev99 on January 20, 2024, 06:34:47 pm
I tried your settings with a 16MHz ATmega644 tester but couldn't reproduce what you've seen. Also after running the RCL monitor a 1µF cap measured fine for all probe combinations.

Can you use the ATmega644 with a 16MHz crystal?
I tried it and it does not work. If I look at the fuse settings for oscillators, it only goes to 8Mhz.
What am I missing?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 21, 2024, 11:19:24 am
Yes, a 16 MHz crystal works fine. The fuse bits are the same as for an 8 MHz quartz (external crystal, 1:1 prescaler). But you need to compile the firmware for 16 MHz (-> Makefile).
Title: Re: $20 LCR ESR Transistor checker project
Post by: jdev99 on January 21, 2024, 05:57:36 pm
I now installed a ATmega644 + 16MHz crystal, and it works great.
The only other thing I want to know is how to improve the zener test values.
A 5.1v read as 5.44v and a 12v read as 13.5v.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 21, 2024, 06:42:18 pm
Could be the test current (too low). Low wattage zeners need about 3 - 5 mA.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jdev99 on January 21, 2024, 10:29:21 pm
It draws 3.7mA for the 5.1v, so it seems like there is enough current.  ???
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 22, 2024, 07:44:48 am
jdev99
A competent and simple solution, as indicated in the screenshot. Selection of the most optimal current and its stabilization for safe testing of high-power and middle(low)power zener diodes.
For more precise adjustment of the measured voltage on the zener diode, in k-firmware the Makefile contains lines for the input resistor divider
# Voltage divider for the external zener voltage measurement 180k / 20k = 10/1
CFLAGS += -DEXT_NUMERATOR=10
CFLAGS += -DEXT_DENOMINATOR=1
Instead of a decimal value, you can use the following numbers for smoother voltage adjustment
CFLAGS += -DEXT_NUMERATOR=100
CFLAGS += -DEXT_DENOMINATOR=10
In your case, to reduce the voltage, you can, for example, try the following values
CFLAGS += -DEXT_NUMERATOR=120
CFLAGS += -DEXT_DENOMINATOR=10

For m-firmware, similar divider settings are in the config.h file
#define ZENER_DIVIDER_CUSTOM
#define ZENER_R1         180000
#define ZENER_R2         20000
Title: Re: $20 LCR ESR Transistor checker project
Post by: rherber1 on January 22, 2024, 09:42:50 am
I have purchased an LCR-TC2 which appears identical to that in Swainster's pics(Reply #8574 on: May 09, 2023, 05:00:09 am). My pcb is marked T7-PLUS V2.0 also and f/w is V3.1E.

My tester exhibits odd behaviour when measuring resistors of 15 Ohms and 18 Ohms in that it identifies them as Inductors with some arbitrary value of inductance and with the nominal resistance shown. If I use 12 Ohms or 22 Ohms these values are correctly identified as Resistor with the nominal values displayed.

The ability of this tester to produce an accurate value of resistance appears to be quite poor. I measured a nominal 56KOhm resistor with two different multimeters and both produce a reading of 56k6 Ohms. The TC2 produces a value of 58k07 - not what you would call close to the result of both multimeters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: wasedadoc on January 22, 2024, 10:36:07 am
Could be the test current (too low). Low wattage zeners need about 3 - 5 mA.
No, the effect would be the opposite.  Low current through a zener gives a lower voltage across it, not higher.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 22, 2024, 11:26:50 am
The Zener stabilization voltage may differ from the rated voltage even with the current allowed for it. Therefore, to be sure that the readings are correct, you must first provide current from the stabilized power supply through the zener diode, which is indicated in the datasheet for it, and then measure the voltage drop with a multimeter. This will be the right choice.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2024, 11:50:14 am
I have purchased an LCR-TC2 which appears identical to that in Swainster's pics(Reply #8574 on: May 09, 2023, 05:00:09 am). My pcb is marked T7-PLUS V2.0 also and f/w is V3.1E.

My tester exhibits odd behaviour when measuring resistors of 15 Ohms and 18 Ohms in that it identifies them as Inductors with some arbitrary value of inductance and with the nominal resistance shown. If I use 12 Ohms or 22 Ohms these values are correctly identified as Resistor with the nominal values displayed.

Have you run the self-adjustment (shorting all three probe pins)? BTW, that TC2's MCU is an LGT8F328.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rherber1 on January 22, 2024, 01:09:29 pm

Have you run the self-adjustment (shorting all three probe pins)? BTW, that TC2's MCU is an LGT8F328.

That procedure is not mentioned anywhere in the instruction pamphlet - so, no, I didn't do it.

Have done it now shorting 1-2-3 together and running a test. Shows 0.11 Ohms 1-2 and 0.14 Ohms 2-3. Then ran a test on the 15 Ohm resistor again and no difference - still says it is an inductor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 22, 2024, 02:20:17 pm
Bummer! Unfortunately some of the tester clones with an alternative MCU come without the self-adjustment feature.
Title: Re: $20 LCR ESR Transistor checker project
Post by: csuhi17 on January 22, 2024, 02:26:35 pm

Have you run the self-adjustment (shorting all three probe pins)? BTW, that TC2's MCU is an LGT8F328.

That procedure is not mentioned anywhere in the instruction pamphlet - so, no, I didn't do it.

Have done it now shorting 1-2-3 together and running a test. Shows 0.11 Ohms 1-2 and 0.14 Ohms 2-3. Then ran a test on the 15 Ohm resistor again and no difference - still says it is an inductor.

https://youtu.be/KPdoprtrfBg?si=xw6ZLrNqGqUZCcVY&t=130 (https://youtu.be/KPdoprtrfBg?si=xw6ZLrNqGqUZCcVY&t=130)

Did the calibration go well for you, like in the video?

It happened to me that the calibration failed, because the resistance value was higher with the short between me.
After pressing Test, it showed two or three resistances between the test points.
Title: Re: $20 LCR ESR Transistor checker project
Post by: slybunda on January 22, 2024, 02:35:56 pm
I have purchased an LCR-TC2 which appears identical to that in Swainster's pics(Reply #8574 on: May 09, 2023, 05:00:09 am). My pcb is marked T7-PLUS V2.0 also and f/w is V3.1E.

My tester exhibits odd behaviour when measuring resistors of 15 Ohms and 18 Ohms in that it identifies them as Inductors with some arbitrary value of inductance and with the nominal resistance shown. If I use 12 Ohms or 22 Ohms these values are correctly identified as Resistor with the nominal values displayed.

The ability of this tester to produce an accurate value of resistance appears to be quite poor. I measured a nominal 56KOhm resistor with two different multimeters and both produce a reading of 56k6 Ohms. The TC2 produces a value of 58k07 - not what you would call close to the result of both multimeters.

thats odd, your tester seems to be a bit like my T7 from the inside but your missing the crystal oscillator: https://www.eevblog.com/forum/testgear/t7-tester-410146/msg5276989/ (https://www.eevblog.com/forum/testgear/t7-tester-410146/msg5276989/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 22, 2024, 03:10:28 pm
thats odd, your tester seems to be a bit like my T7 from the inside but your missing the crystal oscillator: https://www.eevblog.com/forum/testgear/t7-tester-410146/msg5276989/ (https://www.eevblog.com/forum/testgear/t7-tester-410146/msg5276989/)
There is an X2 quartz crystal on the board, but it is small. What this tester lacks is this normal ATMEL chip and the original authors firmware! :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: NF6X on January 22, 2024, 03:42:58 pm
I posted photos of the "AITRIP" brand T7 tester I just got (https://www.eevblog.com/forum/testgear/t7-tester-410146/msg5291197/#msg5291197) from Amazon in slybunda's T7 thread (https://www.eevblog.com/forum/testgear/t7-tester-410146/msg5291197/). Mine has an APT32F172K8T6 microcontroller, and I don't see any crystal or resonator on it. I presume they're using an internal RC oscillator on the microcontroller. When I short 1-2-3, it identifies itself as "FNIRSI-TC1", and does not show a firmware version number.



Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 22, 2024, 03:56:43 pm
NF6X,you bought the most unsuccessful model of a Chinese clone from FNIRSI.
If for clones with LGT8F328 installed, you can replace it with the classic ATmega328 and with a little effort get a completely working version with authors firmware, then your controller in case of failure cannot be replaced with anything. :(
Title: Re: $20 LCR ESR Transistor checker project
Post by: jdev99 on January 22, 2024, 05:17:09 pm
jdev99


For m-firmware, similar divider settings are in the config.h file
#define ZENER_DIVIDER_CUSTOM
#define ZENER_R1         100000        // R17     
#define ZENER_R2         12000          // R18

After measuring the resistors out of circuit, and adjusting above mentioned values, it is now pretty good.
Values below 5v is a bit low, but everything up to 39v is 99% accurate.
I have a TC1, with ATmega644 and "ComponentTester-1.51m" firmware.
Thank you very much for all excellent advice and effort you guys are putting into this little tester.  :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: rherber1 on January 22, 2024, 11:56:43 pm
Bummer! Unfortunately some of the tester clones with an alternative MCU come without the self-adjustment feature.

It certainly seems that this version doesn't have a self test function.

I also tried the factory reset switch on the bottom and it doesn't seem to do anything.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rherber1 on January 23, 2024, 12:00:55 am
I have purchased an LCR-TC2 which appears identical to that in Swainster's pics(Reply #8574 on: May 09, 2023, 05:00:09 am). My pcb is marked T7-PLUS V2.0 also and f/w is V3.1E.

My tester exhibits odd behaviour when measuring resistors of 15 Ohms and 18 Ohms in that it identifies them as Inductors with some arbitrary value of inductance and with the nominal resistance shown. If I use 12 Ohms or 22 Ohms these values are correctly identified as Resistor with the nominal values displayed.

The ability of this tester to produce an accurate value of resistance appears to be quite poor. I measured a nominal 56KOhm resistor with two different multimeters and both produce a reading of 56k6 Ohms. The TC2 produces a value of 58k07 - not what you would call close to the result of both multimeters.

thats odd, your tester seems to be a bit like my T7 from the inside but your missing the crystal oscillator: https://www.eevblog.com/forum/testgear/t7-tester-410146/msg5276989/ (https://www.eevblog.com/forum/testgear/t7-tester-410146/msg5276989/)

This board accepts either the larger xtal in a can or the tiny ceramic version. Mine appears to use the latter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rherber1 on January 23, 2024, 09:31:25 am
thats odd, your tester seems to be a bit like my T7 from the inside but your missing the crystal oscillator: https://www.eevblog.com/forum/testgear/t7-tester-410146/msg5276989/ (https://www.eevblog.com/forum/testgear/t7-tester-410146/msg5276989/)
There is an X2 quartz crystal on the board, but it is small. What this tester lacks is this normal ATMEL chip and the original authors firmware! :D

You might be right about the ATMEL chip and original firmware.

I asked another guy who owns a similar unit and his definitely correctly identifies a 15 Ohm resistor as "Resistor". So perhaps my unit is an imperfect clone of the other "clone". see pic of his unit.
Title: Re: $20 LCR ESR Transistor checker project
Post by: wasedadoc on January 23, 2024, 10:16:55 am
.. see pic of his unit.
Tell the other guy that some of those testers can be switched between Chinese and English text by holding down the Start button  for an extended period.
Title: Re: $20 LCR ESR Transistor checker project
Post by: slybunda on January 23, 2024, 03:32:18 pm
My T7 measured a 10ohm thermistor as 11.7 ohm, but thats gonna vary with room temps but was detected as a resistor
Title: Re: $20 LCR ESR Transistor checker project
Post by: NF6X on January 23, 2024, 05:28:43 pm
It's unfortunate that the clone I got doesn't support the open source firmware, but I think it'll still be suitable for my "is this still a transistor?" testing purposes. Maybe I'll buy or build an Atmel-based one later. This was just the first one I tried buying from Amazon, and I knew there was a pretty high chance that I'd be getting a non-Atmel-based one in January, 2024. So, I'm not too disappointed about it.

Does the open source firmware implement the IR remote control decoder feature? I don't specifically need that feature, but it's kind of neat.

I hope there will eventually be an open source toolchain and English documentation for the APT32F family, so we can easily hack the things it shows up in.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 23, 2024, 05:53:47 pm
The m-firmware supports the detection/decoding of about 15 IR RC protocols (or 22 with the  SW_IR_RX_EXTRA option). You can also transmit about 15 protocols. The firmwares of the Chinese tester clones are all based on the OSHW firmwares (mostly k-firmware), but the manufacturers ignore the obligation to publish their modified versions.
Title: Re: $20 LCR ESR Transistor checker project
Post by: NF6X on January 23, 2024, 06:02:40 pm
Thank you for your explanation. Now I feel more motivated to buy or build hardware which works with the open source code, and maybe even contribute to the open source tester ecosystem in some small way.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on January 28, 2024, 04:55:52 am
This thread is much too long, so I hesitate to post my comparison here. If the mods think this would be better as a separate post, please "Make It So".

I had a MK-328 tester that I bought years ago. It has a real 328P uC and a 8 MHz xtal. I posted a picture of the internals here a few weeks ago (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5277592/#msg5277592 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5277592/#msg5277592)). It is pretty standard for its age. Quite some time ago, I did flash 1.12k firmware on it.

I just bought a TC1 tester, and a MTT-V1 tester (picture below). Both are smaller and use rechargeable lithium batteries. The TC1 has a micro-USB charging jack. The MTT-V1 has a USB-C jack, which surprisingly actually charges via USB-C.

No documentation comes with the TC1, but I did find a PDF online. The MTT-V1 came with a folded color sheet with basic instructions. One thing not documented for the MTT-V1 is how to do a self test. Even though the tester came with three pins shorted together, I couldn't find any way to do a self test.

The MTT-V1 is much thinner, and has swappable adapters - one for SMD, one for a ZIF socket, and one for two buttons to send IR commands.

Both the TC1 and MTT-V1 receive IR codes. the MTT-V1 handles several different manufacturer's codes. I'm not sure about the TC1. The document says Hitachi, but my two IR remotes both speak NEC, which was decoded. Interestingly, the MTT-V1 reports a two digit code, the TC1 reports a four digit code, the two MSD are the same as the MTT-V1.

The MTT-V1 also sends IR codes. To access the send/receive functions, you need to short press the button to go into normal testing mode, wait for testing to finish, then double-press the button to bring up a menu.

There are several YT videos on the TC1. Only one person has published videos on the MTT-V1. If you want to see the inside of the MTT-V1, watch his first video. I tried to take mine apart, but the display is glued in too well, and I didn't want to risk damage.

I did take a picture of the TC1 PCB, which is attached. The uC has the markings removed.

I did some testing of various components with all three testers, using the ZIF sockets. For resistors, capacitors and inductors, I also used my DE-5000 LCR meter, with the built-in slots.

For LCR measurements, none of the four instruments gave the same values. I'll consider the DE-5000 to be the most accurate.

For 1R to 1M all were close, but the old MK-328  agreed more closely with the DE-5000.

For 4.7pf to 470uF, the MK-328 and TC1 were both very close to the DE-5000., although below 33pF, the testers either gave no reading, or an inaccurate one.

For 0.47uH to 820uH, the three testers didn't register an inductor until somewhere between 10uH to 56uH (I didn't test every inductor I had). The MK-328 was closest to the DE-5000.

Next, I tested a variety of semiconductors (you know, those guys who only conduct an orchestra part time). Obvioulsy, I couldn't use the DE-5000 for this.

For the basic values on transistors and diodes, all three were fairly close. However, the MTT-V1 showed some odd values for transistor Ice. It also wouldn't read the only JFET I had (J310G), identifying only the gate. It also showed much higher values for diode reverse current than the other two testers. I'll have to dig up some specsheets to see which is correct. The TC1 showed some extra measurements vs the MK-328, so that may be of use.

As for zener diodes, both the TC1 and MTT-V1 test up to 20V. Looking at the numbers, I'd trust the TC1 more.

I don't need the IR capability, and for LCR measurements, I'd use the DE-5000. I mostly would need the semiconductor testing to identify unknown parts, and sometimes to match parts. For that, either the MK-328 or TC1 would do, with the TC1 having the edge. With some of the odd readings from the MTT-V1, I don't think I'd trust it.

If you don't have a better LCR meter, then the old MK-328 agreed best with the DE-5000.

I really wanted to like the MTT-V1 because of the size, the USB-C charging, and the swappable adapters. The measurements just didn't make it, compared to the two other testers and the DE-5000.

EDIT: One thing I forgot to mention when measuring caps. The DE-5000 used 1kHz for measuring ESR. I'm not sure how the testers measure ESR. All three testers reported much more optomistic ESR numbers, when they did show ESR.

EDIT again: Although the second picture is captioned MTT-V1, it is actually the TC1. I'm not sure how I messed up the name.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 28, 2024, 06:20:15 am
mojoe, As has already been repeatedly said and proven in this topic, it is not advisable to trust testers who are not built on original AVR controllers and do not have the author’s normal firmware to check parts, as there may be unpredictable results. Two respected authors our project have been developing and polishing code for more than 10 years, and this is immediately visible when compared with devices on another platform.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on January 28, 2024, 08:00:03 am
Yes, you don't need to tell me the obvious.  I know full well from reading most of this thread over the years that the newer testers are likely to have non Atmel uC's in them and different firmware. My reason for posting was to let others know how these two newer testers performed, compared to my old one.

Since many people don't want to build one from scratch, we have to buy one. This means buying a Chinese tester. The MK-328 I bought years ago has a real Atmel uC, as I mentioned. And, as numerous posts show, many people are buying various models, all made in China.

Despite all of this, the TC1 tester does a decent job. As I mentioned, for measuring LCR, I have better equipment.

If you can tell me where to buy an assembled tester (or a kit) with a case that uses the correct parts, and the authentic firmware, please do. If this information is in this very long thread, then I must have missed it.

Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 28, 2024, 12:56:43 pm
If you want to buy a tester at the moment the best bet is to look for a DIP ATmega. The problem with the alternative MCUs is that they come with a poorly adapted firmware. All tester clone firmwares are based on the OSHW firmwares (mostly k-firmware) which are tailored to the ATmega MCU family. Some measurements can't be simply ported 1:1 to other MCUs, leading to subpar results or complete screw-ups. Another issue (also for clones with a genuine ATmega with 32kB flash) is the fancy UI. That fancy UI increases the firmware size considerably so that features, cross-checks and other things need to be dropped, resulting in less reliable component detection and less component related values.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on January 28, 2024, 02:07:46 pm
madires, Of course, I’m not 100% sure, since my Chinese colleagues do not provide their source files, but most likely they write the code entirely in the ASM assembly language, which of course reduces the size of the firmware and increases the speed of its operation, but significantly complicates the possibility of customization and configuration many necessary parameters.
Title: Re: $20 LCR ESR Transistor checker project
Post by: alex_D on January 28, 2024, 11:05:26 pm
Yes, you don't need to tell me the obvious.  I know full well from reading most of this thread over the years that the newer testers are likely to have non Atmel uC's in them and different firmware. My reason for posting was to let others know how these two newer testers performed, compared to my old one.

Since many people don't want to build one from scratch, we have to buy one. This means buying a Chinese tester. The MK-328 I bought years ago has a real Atmel uC, as I mentioned. And, as numerous posts show, many people are buying various models, all made in China.

Despite all of this, the TC1 tester does a decent job. As I mentioned, for measuring LCR, I have better equipment.

If you can tell me where to buy an assembled tester (or a kit) with a case that uses the correct parts, and the authentic firmware, please do. If this information is in this very long thread, then I must have missed it.

This kit is the safest bet to use with OSFW and you get an Atmega with a DIP socket.
https://www.ebay.com/itm/142849416622 (https://www.ebay.com/itm/142849416622)
Title: Re: $20 LCR ESR Transistor checker project
Post by: NF6X on January 29, 2024, 12:01:19 am
Despite its shortcomings, I like my new APT32F172K8T6 based tester. It has gotten me interested in designing my own ATmega-based variant. I think I'll order one of those DIP socketed kits to start playing with the m-tester code while I begin designing my own hardware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on January 29, 2024, 03:37:46 am
This kit is the safest bet to use with OSFW and you get an Atmega with a DIP socket.
https://www.ebay.com/itm/142849416622 (https://www.ebay.com/itm/142849416622)

Thanks for the link. However, there is no description of capabilities. Do you know more about it?

If it doesn't do zeners, then it's pretty much the same as my old MK-328. The only extras I can see is the rotary encoder and the DIP socketed uC.

No internal battery (9V or otherwise), so not really portable. Also, these acrylic open frame "cases" aren't much protection if you want to toss it in with other tools to take with you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: mojoe on January 29, 2024, 04:01:33 am
I just checked some diode datasheets. As I suspected, the MTT-V1 is wrong for diode reverse current. It's reporting uA values, which should be in the nA range. It's not just a matter of the wrong units, the numbers are just plain wrong.

Both the MK-328 and TC1 values are similar to each other. The specsheet uses a higher voltage to test this, so it lists a higher reverse current, but still in the nA range.
Title: Re: $20 LCR ESR Transistor checker project
Post by: wasedadoc on January 29, 2024, 03:54:05 pm
This kit is the safest bet to use with OSFW and you get an Atmega with a DIP socket.
https://www.ebay.com/itm/142849416622 (https://www.ebay.com/itm/142849416622)

Thanks for the link. However, there is no description of capabilities. Do you know more about it?

If it doesn't do zeners, then it's pretty much the same as my old MK-328. The only extras I can see is the rotary encoder and the DIP socketed uC.

No internal battery (9V or otherwise), so not really portable. Also, these acrylic open frame "cases" aren't much protection if you want to toss it in with other tools to take with you.
I got one of those kits about 5 years ago.  With the same case I think it was close to £10.

The case does hold the 9 Volt battery inside.  It does not do zener diodes but has some extras.

A frequency counter.

A square wave generator of adjustable frequency.

A 10 bit PWM generator

A DS18B20 tester

A DHT11 tester

An IR_Decoder.  Needs a 3 pin IR sensor plugged into the ZIF socket

A Voltmeter

Section 2.9, Fig 2.27 of the attached pdf.


Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 29, 2024, 04:59:51 pm
This kit is the safest bet to use with OSFW and you get an Atmega with a DIP socket.
https://www.ebay.com/itm/142849416622 (https://www.ebay.com/itm/142849416622)

That's the classic AY-AT (aka GM328A) and still a good choice. And it's supported by both OSHW firmwares.
Title: Re: $20 LCR ESR Transistor checker project
Post by: NF6X on January 29, 2024, 05:01:12 pm
For my own component tester variant, I want to use a 3M Textool transistor test socket (or one of the less expensive ones from Sullins) like this one from my Tektronix 576 curve tracer. Sadly, they apparently aren't made with this lovely green plastic any more. I haven't seen a TFXDTOL brand knockoff of this socket on Aliexpress, so it won't be a cheap approach.

[attach=1]

If I include the Zener diode measurement function, one simple approach would be to have a 3PDT switch to connect the test socket to either the normal probe pins or the Zener test circuit. It would be nicer if there was just one button, though. I'm thinking about including relays to select the normal or Zener test modes, and modifying the m-firmware to automatically perform the Zener test when it detects a single diode with its cathode on pin 1 and its anode on either pin 2 or 3.

Do y'all think it is likely to be problematic for my tester to always try applying a reverse bias of around 30V with 5mA current limit whenever it sees a diode junction? Is that likely to burn out random components?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on January 29, 2024, 08:18:23 pm
Do y'all think it is likely to be problematic for my tester to always try applying a reverse bias of around 30V with 5mA current limit whenever it sees a diode junction? Is that likely to burn out random components?
I guess you're talking about to trigger the 30V generation at the end of all the other tests, provided it really looks it's a PN junction?
However, IMHO to apply 30V to a DUT can be arguably risky. Let's say you have a tiny low-voltage component (we could even say it's a 3-leg smd with dirt/loose contact on one), you could damage it. If you're doing your own CTester, I would rather assign a different set of terminals for that (like the TC-1 and its variants). This is just my opinion, for sure other people can shed more light on this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on January 30, 2024, 09:14:10 am
I agree. For example, some LED types don't like high reverse voltages.
Title: Re: $20 LCR ESR Transistor checker project
Post by: NF6X on January 30, 2024, 03:35:45 pm
Ok, thank you both. The automatic Zener test idea is out. I would still like to have a single transistor test socket for the device under test, so I'll provide some way for the user to configure the unit's test mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Dumidan on January 31, 2024, 04:37:29 pm
Hello!

A test of a reverse-biased pn junction would be useful to establish the maximum reverse voltage, but for the test to be non-destructive, the current must be limited to a very small value, on the order of 0.1 mA or less. The test can be done on the section reserved for measuring zenner diodes, using a special current limiting stage. In no case can it be implemented as an automatic function due to special hardware requirements.
Title: Re: $20 LCR ESR Transistor checker project
Post by: NF6X on January 31, 2024, 04:48:03 pm
Adding a low-current reverse breakdown test would push the tester's capabilities a tiny bit closer to a curve tracer. That has me wondering what a low-cost curve tracer inspired by the cheap LCR tester project might look like.
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on January 31, 2024, 05:40:47 pm
Not exactly inspired by the cheap LCR tester project, but as simple as it can be:

https://www.instructables.com/Transistor-Curve-Tracer/ (https://www.instructables.com/Transistor-Curve-Tracer/)

EDIT: Yes, it's inspired by this project: "I was very impressed when I bought one of the wonderful LCR-T4 testers by Markus Frejek and others but I wanted it to tell me more about the components so I started to design my own tester."
Title: Re: $20 LCR ESR Transistor checker project
Post by: pizzigri on February 02, 2024, 10:10:43 pm
Not exactly inspired by the cheap LCR tester project, but as simple as it can be:

https://www.instructables.com/Transistor-Curve-Tracer/ (https://www.instructables.com/Transistor-Curve-Tracer/)

EDIT: Yes, it's inspired by this project: "I was very impressed when I bought one of the wonderful LCR-T4 testers by Markus Frejek and others but I wanted it to tell me more about the components so I started to design my own tester."

Hi ! Did you build it? I tried some time ago (actually two years ago) using the smd version but it never worked correctly, possibly my fault….
Title: Re: $20 LCR ESR Transistor checker project
Post by: morgan_flint on February 03, 2024, 07:06:55 pm
No, I haven't built it.

BTW, I think it'd be interesting a screenless version, just sending commands and seeing the results from a PC
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pilot Error on February 06, 2024, 05:27:35 pm
Hello everyone, I'm a bit new to this so I've now got a collection of testers with unmarked chips. I was interested when I read the information about this LCR-TC3 as it said using 'imported chips'.
Anyway there is a Atmel 328p in this so what does everyone think?
I've checked the pins and it's genuine as far as I can tell. Also it has two 180mah batteries. This was from an AliExpress seller  :)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 06, 2024, 07:45:39 pm
Welcome to the forum.

Here a post relevant to the subject by our guru madires:

Some hints on identifying the MCU:
- MCU in DIP is usually an genuine ATmega.
- APT32F172K8T6 has different power pins:
  - 32-LQFP/QFN: 18=Vss, 19=Vdd (ATmega328 32-TQFP: 5=Gnd, 4=Vcc)
- APT32F172K8T6 uses SWD port for ISP:
  - 5 pins: Vdd, Vcc, F_SDAT, F_SCLK, F_RST
- Testers with APT32F172K8T6 often lack a quartz crystal.
- LGT8F328 has slightly different pins:
  - QFP32L: 21=PE2/SWD (ATmega328 32-TQFP: 21=Gnd)
- LGT8F328 uses SWD port for ISP:
  - 5 pins: Gnd, Vcc, SWD, SWC, Reset
- Clone variants with an genuine ATmega are usually about EUR/US$ 5 more
  expensive than the variant with a different MCU.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Pilot Error on February 07, 2024, 07:58:49 am
Welcome to the forum.

Here a post relevant to the subject by our guru madires:

Some hints on identifying the MCU:
- MCU in DIP is usually an genuine ATmega.
- APT32F172K8T6 has different power pins:
  - 32-LQFP/QFN: 18=Vss, 19=Vdd (ATmega328 32-TQFP: 5=Gnd, 4=Vcc)
- APT32F172K8T6 uses SWD port for ISP:
  - 5 pins: Vdd, Vcc, F_SDAT, F_SCLK, F_RST
- Testers with APT32F172K8T6 often lack a quartz crystal.
- LGT8F328 has slightly different pins:
  - QFP32L: 21=PE2/SWD (ATmega328 32-TQFP: 21=Gnd)
- LGT8F328 uses SWD port for ISP:
  - 5 pins: Gnd, Vcc, SWD, SWC, Reset
- Clone variants with an genuine ATmega are usually about EUR/US$ 5 more
  expensive than the variant with a different MCU.

Thank you for the welcome message and this useful information. After checking the grounds and vcc it seems this tester does have a genuine Atmel chip. I shall explore it's functionality
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 07, 2024, 07:54:12 pm
Continuing with the TC1, I have one FNIRSI 324p-based (with power MCU as U8, transformerless, still with its factory firmware). It has a failure: Most of the times doesn't work, but sometimes work. I found the failure after I rubbed away the ugly whitened factory solders with alcohol. I had it on a drawer until recently.

Given the fact is not easy to find an ATmega unit, I'm trying to troubleshoot it. I describe its weird behaviour:
.-Most of the times get stucked with only "M-TESTER" message on screen. U6 (boost converter) generates 6.1V and the 78L05 4.9V. I can power it off by long-pressing the button
.-If it pass the boot banner, sometimes shows wrong (lower) battery voltage, and measures a phantom uF-range capacitor, sometimes between terminals 1 and 2, sometimes between 2 and 3
.-I already cleaned everything with alcohol or contact cleaner several times, and redo the solderings. While doing this, I found if I moisturize U6 with little bit of alcohol, it works for some minutes, with U6 delivering 5.9V
.-Sometimes works fine on its own

[EDIT]: Desoldering U6 and cleaning beneath it didn't solve the issue.
[EDIT]: I haven't found an Schematic of the transformerless variant to better study U6 behaviour here, In the meantime, I'm looking at the SB6284 datasheet.

Has somebody found/fixed an odd failure like this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 08, 2024, 09:52:25 am
-If it pass the boot banner, sometimes shows wrong (lower) battery voltage, and measures a phantom uF-range capacitor, sometimes between terminals 1 and 2, sometimes between 2 and 3

That points to a power supply issue. Could be something like a nearly shorted MLCC around the boost converters or the 78L05.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 08, 2024, 11:52:43 am
I think the failure is located around the boost converter (lC marking B628), because if I somehow alter a little its Q point, it works. In fact I re-centered the output capacitor, and cleaned beneath U6 and some resilient goo around L1 and it has been working for a few hours. Fingers crossed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 08, 2024, 12:18:30 pm
Heating up the MLCC could have fixed the issue.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 08, 2024, 01:28:49 pm
It could be, because this time I heated it a lot (and even rolled it over). I keep watching it.

Anyways, I was about to ask you:
a nearly shorted MLCC.
IIUC, you're describing that some layers can be shorted or compromised? If that's the case, it should measure a lower capacity and/or high ESR, and/or high Ileak and/or high Vloss, right?. I didn't notice some really bad values of it (from k-firmware), but without knowing the nominal value for my transformerless variant, I'm not sure. Still, how come when it had some vapour/liquid residues nearby it worked?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 08, 2024, 02:51:14 pm
MLCCs can fail in different ways. One is a dead short, and another is a low resistance (a few or 10s of Ohms). And there's also some humidity issue which can sometimes be resolved by simply heating up the cap. I have no idea why the alcohol helped temporarily.
Title: Re: $20 LCR ESR Transistor checker project
Post by: YouCanDoIt on February 08, 2024, 07:54:39 pm
Hello to all guys,
I just joined the forum after spending a good amount of time in researches without coming up to a solution.
From what I have understood, as of now a device with an ATMega644/ATMega1284 and higher is the most desiderable because allows higher accuracy and many more features.
Hovewer, in the clone comparison chart I only see Hiland M644 which is limited to ATMega644. Very hard to find and sold at $40 in a couple of places. Some web pages before this one, an user said that it is just a waste of money which makes me think there would not be any significant difference between the old versions.
The list also shows some "LCR-T** marked as "possible ATMega644". I suppose the situation would be even worse for such models.

What seems to be very amazing is the Mega-4GSL, but I have not been able to find any DIY kit anywhere. Did someone here in the forum tried to build one? Where to find all the needed parts? I have no idea on the costs, but if there are other interested users we could create a purchase group and help each other in the build process.

Apart from this, are there any other alternatives?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 08, 2024, 10:30:44 pm
Welcome to the forum.

Currently it's not easy to find an original ATmega unit (I guess politics and economics reasons). Therefore you can buy any and use it with it's original Chinese firmware (keep in mind the fancier the interface, the less functionality). Or you can keep looking for an original one, being able to flash the OSHW firmware discussed on this long thread, where you can select a set of the most important functions to your liking. Note: If you buy a DIP version, you have better chance of getting a real 328.

Or as you said, you can build one yourself (with an 644 or 1284, for reacher fetures set), alone, or along with some other European readers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jdev99 on February 09, 2024, 09:34:48 pm
Just received this one, with original ATmega328P. They are still out there.  ;)

https://www.aliexpress.com/item/1005005497252414.html?spm=a2g0o.order_list.order_list_main.5.52321802KA7hcS (https://www.aliexpress.com/item/1005005497252414.html?spm=a2g0o.order_list.order_list_main.5.52321802KA7hcS)

(https://ae01.alicdn.com/kf/S72f6a266164a48b39711e139f31f0810v.jpg)
Title: Re: $20 LCR ESR Transistor checker project
Post by: YouCanDoIt on February 09, 2024, 10:25:38 pm
Currently it's not easy to find an original ATmega unit (I guess political and economic reasons). Therefore you can buy any and use it with it's original Chinese firmware (keep in mind the fancier the interface, the less functionality). Or you can keep looking for an original one, being able to flash the OSHW firmware discussed on this long thread, where you can select a set of the most important functions to your liking. Note: If you buy a DIP version, you have better chance of getting a real 328.
Many thanks for your help. I was originally planning to buy "M328Kit+TFT(AY-AT)" I saw on the chart since this one seemed to be the best one. Is right? Please accept my apologies for the stupid questions, but I am totally newbie about transistor testers. This model seems to be non DIP and therefore should be easier to find a genuine version, but what is the difference between DIP and non DIP versions?
There is still the problem that an ATMega328 can't run a full feature firmware and its low accuracy. Given the low price of the controller, I am wondering if I could just replace the bundled ATMega328 with an ATMega1284 and flash it with the related firmware.

Or as you said, you can build one yourself (with an 644 or 1284), alone, or along with some other readers.
Yes, this is the option that I'm currently evaluating, but it's getting harder than I thought due to the lack of sources. I thought to the Mega 4gsl because it has been mentioned here, but I should first try to understand how it really performs to see if it's worth all the efforts to build one.

I'm also unable to estimate costs. There are 150 components. By a quick (and dirty) look up it should be around 15-20$ for the board components, $5-15 for LCD+battery (depending from what can be adapted). It should remain the PCB and the case, but I have not been able to find these anywhere. The user pizzigri posted here what he spent to build one and I got totally shocked to see it was 140 € (euro). Hope it has been a typo.

If someone can post some documentation source I would really appreciate. The PCB photo shows a non existent link to https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/) and I'm wondering if this is a dead project. The firmware is heavily customized and I have read somewhere it is private. I am concerned about updates given the fact that the official ones regularly published will not work for sure.

Just received this one, with original ATmega328P. They are still out there...
Many thanks for the link. It seems to be a version of the GM328A different from the ones showed in the comparison chart. Isn't "M328Kit+TFT(AY-AT)" a better choice?
Title: Re: $20 LCR ESR Transistor checker project
Post by: YouCanDoIt on February 09, 2024, 11:08:32 pm
I forgot to mention that I have also considered smart tweezers given the fact that now prices are more accessible. For example I saw here in the forum DT71 and although I have read many good reviews on the web, the one posted here is not good at all:
https://www.eevblog.com/forum/blog/eevblog-1335-miniware- (https://www.eevblog.com/forum/blog/eevblog-1335-miniware-)$70-dt71-lcr-tweezer-review
That topic was around 3 years ago, so may be they managed to improve the quality through firmware and/or hardware changes.
I suppose that in the meanwhile new models entered in the market, but I'm not an expert and I have not gone further.

What I would like to know is that, for such price range, smart tweezers could be a better replacement of any of the best testers discussed on this topic.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 10, 2024, 12:45:36 am
If you buy a DIP version, you have better chance of getting a real 328.
but what is the difference between DIP and non DIP versions?
(Besides one being rectangular and larger whereas the other square and smaller), as we have been discussing on this thread, it seems the knock-off MCUs are being manufactured on small square encapsulations (cheaper), so that's why some of us think if you look for a DIP28 ATmega328P-PU, and if the vendor photo it's accurate, you have chances of obtaining a read one (with 32KB of flash, of course).
There is still the problem that an ATMega328 can't run a full feature firmware and its low accuracy. Given the low price of the controller, I am wondering if I could just replace the bundled ATMega328 with an ATMega1284 and flash it with the related firmware.
If you have a real ATmega, you can evaluate what changes you could make. Or, if you have an LGT8F328P-based unit, and you have a real ATmega, you could adjust the pinout and make the replacement.
If someone can post some documentation source I would really appreciate. The PCB photo shows a non existent link to https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/) and I'm wondering if this is a dead project. The firmware is heavily customized and I have read somewhere it is private. I am concerned about updates given the fact that the official ones regularly published will not work for sure.
kubi48, madires, and indman have posted documentation on different sites. madires has gathered many of that  (including an overview I composed) at github (https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation).
Title: Re: $20 LCR ESR Transistor checker project
Post by: rfink07 on February 10, 2024, 12:56:50 am
Hi, first time posting here. Let me know if there is a better place to ask this.

I bought a variant of this product recently, mostly to measure transistor gain. I've measured several 2n3094 and 2n3096 components, and they all measure hFE ~ 370. If I'm reading the datasheets right, it shouldn't exceed 300 (and usually be much lower).
https://www.amazon.com/Mega328-Digital-Transistor-Resistance-Capacitance/dp/B07WT9VVZB#customerReviews (https://www.amazon.com/Mega328-Digital-Transistor-Resistance-Capacitance/dp/B07WT9VVZB#customerReviews)

Am I missing something? I saw that there can be measurement errors for leaky parts (germanium), but haven't seen complaints about common Si parts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rsjsouza on February 10, 2024, 01:12:41 am
Assuming the transistors are legit, historically the hfe alone is a parameter that has a wide variability across manufacturers and even within the same manufacturer or the same batch. Also, it is highly dependent on the bias applied to the transistor.

I wouldn't rely much on it, unless you are talking variations of orders of magnitude...
Title: Re: $20 LCR ESR Transistor checker project
Post by: rfink07 on February 10, 2024, 04:47:16 pm
Thanks - the main reason I am confused is I measured ~10 components and they are remarkably consistent, all between 360-380, which differs from the datasheet
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 10, 2024, 04:56:59 pm
I bought a variant of this product recently, mostly to measure transistor gain. I've measured several 2n3094 and 2n3096 components, and they all measure hFE ~ 370. If I'm reading the datasheets right, it shouldn't exceed 300 (and usually be much lower).
https://www.amazon.com/Mega328-Digital-Transistor-Resistance-Capacitance/dp/B07WT9VVZB#customerReviews (https://www.amazon.com/Mega328-Digital-Transistor-Resistance-Capacitance/dp/B07WT9VVZB#customerReviews)
Am I missing something? I saw that there can be measurement errors for leaky parts (germanium), but haven't seen complaints about common Si parts.

You must clear understand that ONLY the original autors firmware installed on the device can to a greater extent guarantee the reliability of the results when measuring transistor parameters. And this is provided that the hardware of the tester is in good working order, the supply voltage of the microcontroller is well stabilized and clean. If your tester has original Chinese firmware installed, no one will give you any guarantees regarding the correctness of the results of testing various parts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: YouCanDoIt on February 10, 2024, 06:41:49 pm
If you buy a DIP version, you have better chance of getting a real 328.
but what is the difference between DIP and non DIP versions?
(Besides one being rectangular and larger whereas the other square and smaller), as we have been discussing on this thread, it seems the knock-off MCUs are being manufactured on small square encapsulations (cheaper), so that's why some of us think if you look for a DIP28 ATmega328P-PU, and if the vendor photo it's accurate, you have chances of obtaining a read one (with 32KB of flash, of course).
There is still the problem that an ATMega328 can't run a full feature firmware and its low accuracy. Given the low price of the controller, I am wondering if I could just replace the bundled ATMega328 with an ATMega1284 and flash it with the related firmware.
If you have a real ATmega, you can evaluate what changes you could make. Or, if you have an LGT8F328P-based unit, and you have a real ATmega, you could adjust the pinout and make the replacement.
Many thanks for your help. I will ensure to follow these guidelines if I will end up with a clone. I will post the parts I found and I would appreciate if you could ensure I will not do mistakes.

If someone can post some documentation source I would really appreciate. The PCB photo shows a non existent link to https://www.mikrocontroller.net/svnbrowser/transistortester/ (https://www.mikrocontroller.net/svnbrowser/transistortester/) and I'm wondering if this is a dead project. The firmware is heavily customized and I have read somewhere it is private. I am concerned about updates given the fact that the official ones regularly published will not work for sure.
kubi48, madires, and indman have posted documentation on different sites. madires has gathered many of that  (including an overview I composed) at github (https://github.com/madires/Transistortester-Warehouse/tree/master/Documentation).
Thanks, the link helped me a lot. I have read all the stuff included the faqs and now I have a better idea on how things work. However, even after having followed all the links available in github and its pdf files, unfortunately I didn't found anything about Mega 4gsl.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rfink07 on February 10, 2024, 08:30:54 pm
Update: I made a simple voltage measurement circuit for the transistors and it read... exactly the same as the meter.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 11, 2024, 06:35:37 pm
Many thanks for your help. I will ensure to follow these guidelines if I will end up with a clone.
Thanks, the link helped me a lot. I have read all the stuff included the faqs and now I have a better idea on how things work.
Welcome, and please note there's a "Say thanks" button on the forum  ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 12, 2024, 01:31:00 pm
I've updated my FAQs. Attached.
Title: Re: $20 LCR ESR Transistor checker project
Post by: YouCanDoIt on February 12, 2024, 08:41:41 pm
Many thanks for the updated Faq!
In the spirit of sharing I post a link (https://radiokot.ru/forum/viewtopic.php?f=51&t=126441) where is possible to buy the parts for the MEGA 4GSL. Prices are good and should be available as DIY kit or professionally assembled. Revision should be the latest (2022) while the one I saw posted in the topic is 2015.

I am in doubt if I should go with a Mega 4GSL or an Hiland M644 (which I will customize with all the possible mods I can find here in the forum including the MCU replacement). Do you think they are at the same level or a Mega 4Gsl is still far better even than a modded M644?
What you would buy if you were me?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 12, 2024, 11:12:00 pm
Continuing with my WIP clone, I found a major issue with one of the latest m324pa transformerless TC1 clones, limiting the OSHW mod posibilities: the manufacturer modified the push button behaviour so is no longer directly connected to the STC, but between two(three) transistors, where the power_lock is no longer triggered by the STC but from the ATmega itself (pin16 high on my m324pa), and the push button sends a low on pin42 of my m324pa. Therefore, the known "two vanilla transistors mod" to flash OSHW firmware is no longer valid for this model.

I attach a [WIP] diagram looking similar to the unit on my benchtop.

So what do we do now: create a new circuit for U8(STC) substitution, and/or create a new variant of the m-firmware config for this case? (I can test either).

In any case, a friendly warning for other Users until this is solved: please check what ATmega TC1 clone variant you have before attempting to flash the OSHW firmware.

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 13, 2024, 07:35:51 am
Feliciano, you have become the “lucky” owner of another FNIRSI product, congratulations! ;)
The engineers of this company seem to have set the task of making a product that does not lend itself to such a simple upgrade to the original transistor tester design.
However, this remark applies to all FNIRSI products - for the most part, hastily put together low-quality products with the goal of getting the maximum benefit from the sale as quickly as possible and then forgetting about support and eliminating errors for the consumer.

My thoughts on finalizing this miracle of Chinese thought:
1. Remove STC and forget about it!
2. Try to improve the circuit using this option, which I showed below.
3. Check the assignment of the display contacts to the microcontroller, as they may also differ from the standard ones.
4. Of course, you will need to adapt the autors' firmware for this clone, since cutting the tracks and laying new conductors will be ugly.
But, if desired, this option can be implemented. Although, to be honest, I wouldn’t waste my time on this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 13, 2024, 09:19:46 am
GM328A up and running on 1.13k   Non removable MCU
Files I changed attached
mega328_color_kit Makefile and lcd_defines.h  This display is mounted the opposite of other older GM328A I had to reverse the settings in lcd_defines.h

How I did it I put on GitHub
https://github.com/carl1961/New-GM328A
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 13, 2024, 09:44:43 am
carl1961, What frequency is the quartz currently set to?
1.13k is set to 8 MHz, and 1.51m is set to 16 MHz. Does this tester work stably at 16MHz?
And one more note - during measurements, tests and work with the device, no conductors should be connected to the ICSP bus! This can greatly ruin calibration and test results.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 13, 2024, 12:33:42 pm
Feliciano, you have become the “lucky” owner of another FNIRSI product, congratulations! ;)
to be honest, I wouldn’t waste my time on this.
indman, I respect your opinion, but you should agree that it's not only FNIRSI, as most of "the chinese comrades" cut costs/corners wherever they can. So for most of us, unless we are lucky and get a very old stock, the chances for flashing the OSHW and enjoying all its benefits are more limited as time passes. At least, when rolling the dice, my luck got me an apparently genuine 44pin MCU.

So, I rather invest some time on this unit than putting it aside or thowing it away. But to convert this schematic to the original one it's not feasible, as the changes are too many. Therefore if @madires and you and other readers can please support this new mod, I will appreciate it, and I think it will be of benefit for other "lucky" owners too.

My thoughts on finalizing this miracle of Chinese thought:
1. Remove STC and forget about it!
2. Try to improve the circuit
As I don't want to cut/lay many traces: I haven't spent much time trying to understand the m-firmware code, I don't know whether the communication between PD1<->PD2 is needed (which could be acheived by a resistor). And about pulling PD1 low for reset or menu access, and PD2 high for triggering the boost converter, I don't know whether this can be achieved by another STC substitution circuit, and/or by connecting it differently, and/or by some tweaks on the code. In fact, by reading the power supply part of the similar schematic (which I'm adapting from an m328p TC1 clone), on my unit the press of the button is detected by a low on pin 42, answered with a high on pin 16 to trigger the boosters. Could it be to use the traditional auxiliary PCB, but connecting P1 to Q2c and P3 to Q3b (by an additional resistor) the way to go, ar at least part of it? As I said, I don't know the code, so I can't tell.

3. Check the assignment of the display contacts to the microcontroller, as they may also differ from the standard ones.
I will. In the meantime, I can tell the ISP is the standard one, and gets recognized by my USBasp as an m324pa.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 13, 2024, 12:41:51 pm
Continuing with my WIP clone, I found a major issue with one of the latest m324pa transformerless TC1 clones, limiting the OSHW mod posibilities: the manufacturer modified the push button behaviour so is no longer directly connected to the STC, but between two(three) transistors, where the power_lock is no longer triggered by the STC but from the ATmega itself (pin16 high on my m324pa), and the push button sends a low on pin42 of my m324pa. Therefore, the known "two vanilla transistors mod" to flash OSHW firmware is no longer valid for this model.

I think you can simply ignore the STC of your TC1 variant, i.e. no need for the mod. Or remove it, as indman suggested.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 13, 2024, 01:00:35 pm
So, I rather invest some time on this unit than putting it aside or thowing it away. But to convert this schematic to the original one it's not feasible, as the changes are too many. Therefore if @madires and you and other readers can please support this new mod, I will appreciate it, and I think it will be of benefit for other "lucky" owners too.

All what we need might be just the pin assignment of the ATmega324 to configure the firmware accordingly.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 13, 2024, 01:11:40 pm
I think you can simply ignore the STC of your TC1 variant, i.e. no need for the mod. Or remove it, as indman suggested.
Thanks for replying. I had that gut feeling: the mod could be simpler. However, do the m-firmware?:
the press of the button is detected by a low on pin 42, answered with a high on pin 16 to trigger the boosters.
(I meant at the boot time. Of course pin 42 should be also read for menu access, as pin 16 should be high during operation).

On the other hand, I'm checking this soldered display, and uses a different pin mapping (from right to left bottom-view):
1=GND, 2=Vcc, 3=PB4 (44), 4=PB3 (43), 5=PB5 (1), 6=PB7 (3)
Is that what you meant by:
All what we need might be just the pin assignment of the ATmega324 to configure the firmware accordingly.


So what do you think? Shall we forget the auxiliary PCB, remove the STC (for power consumption reduction), adjust the config, make, and flash? Or something else needs to be adjusted?
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 13, 2024, 02:27:12 pm
It is running with the 8 hz crystal , I removed the 16 hz when I was having screen issues after I read in Karl-Heinz manual where he said something about , Logic Gate Chips on some of these boards and 16 hz not working on them, as this board has a no name china 20 pin Logic Gate Chip.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 13, 2024, 02:36:27 pm
carl1961, This is exactly the nuance I wanted to clarify with you.
The use of an additional microcontroller, which acts as a command translator for BGR displays as well as for the 8-bit paralell display that is installed in your clone version, does not allow full operation at a frequency of 16 MHz.
For whom this frequency factor is important, you should refrain from purchasing such GM328A models or find and connect a standard classic RGB SPI ST7735 display directly to the ATMega328 ports without an extra chip. ;)
Somewhat earlier, one of the participants in the Russian-language forum identified the marking of this 20-pin chip - HC89S003A.
A similar controller 24-pin HC89F0531 can also be installed.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 13, 2024, 02:44:00 pm
carl1961, This is exactly the nuance I wanted to clarify with you.
The use of an additional microcontroller, which acts as a command translator for BGR displays as well as for the 8-bit paralell display that is installed in your clone version, does not allow full operation at a frequency of 16 MHz.
For whom this frequency factor is important, you should refrain from purchasing such GM328A models or find and connect a standard classic RGB SPI ST7735 display directly to the ATMega328 ports without an extra chip. ;)
I bought this thing before I even knew about the firmware.
Thanks for the advice too, I will remove the ISP jig when I am done playing with this. I still trying to get the 1.51m to work, seems all the reason for not working is the 7735 driver.
Yes ,  now that you gave that chip number, it is more readable LOL in this photo of another similar model as mine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: jdev99 on February 13, 2024, 03:11:51 pm

Just received this one, with original ATmega328P. They are still out there...
Many thanks for the link. It seems to be a version of the GM328A different from the ones showed in the comparison chart. Isn't "M328Kit+TFT(AY-AT)" a better choice?

I don't know if it is better, it does have firmware version 1.12k
Title: Re: $20 LCR ESR Transistor checker project
Post by: NF6X on February 13, 2024, 03:19:08 pm
I am new to the transistor tester world, and I'm missing some context and history. Why is that additional STC microcontroller in there? Is that a feature of any of the OSHW designs, or something that the clone manufacturers added? I only see it connected to two ATMega pins in Feliciano's draft schematic. If it's not driving any other hardware, I don't understand why they spent money putting it on the board instead of implementing whatever it does in ATMega firmware. I saw indman's comment about it translating LCD commands, but I don't grok its reason for being there yet.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 13, 2024, 03:37:02 pm
NF6X, STC is an 8-pin power management controller that Chinese engineers have implemented in some clone models.
And the 20-pin(24-pin) microcontroller is another direction of Chinese engineering. They use crappy cheap BGR displays and connect them to ATMega that way. It's clear? In both cases, these Chinese tricks only worsen the design of the original author's project, which is optimally designed with a minimum number of parts used. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: NF6X on February 13, 2024, 03:42:16 pm
I'm having a hard time wrapping my brain around the idea that they spent money on a whole microcontroller to manage the power button instead of implementing it in the main microcontroller firmware for free, given how profit-motivated I expect the clone manufacturers to be. Does it normally have additional connections not shown in Feliciano's draft schematic?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 13, 2024, 03:53:05 pm
NF6X, using STC involved adjusting the time (from 10 seconds to 25 seconds) until the device was completely powered off.
But this time can be easily configured in advance and in the author’s project. So I don’t see any justification for using an additional controller. Maybe someone else can explain it to you better? ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 13, 2024, 03:56:56 pm
The short STC story:
The STC15L104 on the older TC1 and variants is used as a timing/power MCU. On the older factory firmware there was a communication between it and the MCU in order to hold the 5V, and for how long. It had high standby consuption (IIRC it was the 3.3V unit overdriven @VBatt-Vd). Later the manufacturers updated it with a better model. Later the manufacturers removed as by the schematic indman shared recently (and also replaced the transformer with a second booster). You can refer to the pages around May 2018 for the whole STC&TC1 discussion/details. Here I attach the original schematic as reference.

And that's what's puzzling me with my different STC-based TC1:
At the first press of the button, 5V is generated and the MCU will power up, with a low on pin 42. It shall reply with an steady high on pin 16 for keeping the 5V. If another low comes on pin 42, it shall be processed as menu enter (if held low, IIRC), or reset (if quickly returned to high). As I said, I don't know what normally m-firware does with these pins, so I don't know whether it can be adjusted on the config, or it had to be a different subrutine, or it can be accomplished by an external circuit taking Vbatt and 5V (from different places), reading the low from the push button from Q2 transmitting it to PD1, and reading the high on PD2 and transmitting it to Q3. I'm waiting for confirmation on whether the additional workaround is not needed, else, which shall be the better approach.
Title: Re: $20 LCR ESR Transistor checker project
Post by: NF6X on February 13, 2024, 04:13:49 pm
The best hypothesis I've come up with so far is "firmware engineer's uncle owns the local counterfeit STC factory, and snuck the part into the tester design for a kickback".
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 13, 2024, 04:18:32 pm
NF6X, I, for example, it does not bother me in any way, and I will not and do not want to bother with hypotheses as to how and why details absolutely unnecessary for the project appeared. If you are so concerned about it, ask a Chinese engineer, such as FNIRSI, directly!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 13, 2024, 04:20:52 pm
Agree. Please lets focus on the matter in question: how to make this work with OSHW firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 13, 2024, 04:29:57 pm
Feliciano,you have checked the display connection and identified the controller pins. Are the rest of the peripherals connected in the standard way or are there also differences from the original circuit? There are a lot of unclear points on the schematic you showed earlier, the pins of the ATMega324 are not labeled. It would be nice if you could draw a more detailed circuit diagram.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 13, 2024, 04:31:54 pm
Indeed:
I'm checking this soldered display, and uses a different pin mapping (from right to left bottom-view):
1=GND, 2=Vcc, 3=PB4 (44), 4=PB3 (43), 5=PB5 (1), 6=PB7 (3)

And not all the pins are labeled because I'm writing over an m328p schematic [WIP].
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 13, 2024, 04:34:54 pm
That's understandable, that's not what I'm asking. To which ports are connected 6 measuring resistors, ION, calibration capacitor, IR detector?
This is all to be considered when customizing new firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 2hry on February 13, 2024, 05:42:19 pm
@Feliciano

Your tester looks like my JOYIT T7.
I have removed the Stc chip, and flashed m-firmware.
It is not working anymore, because the srv05 got damged, but i made some notes of the pinout.

LCD_RES          PB4           
LCD_DC           PB3
LCD_SCL          PB7
LCD_SDA          PB5
LCD_OFFSET_X     2               
LCD_OFFSET_Y     1               
LCD_FLIP_X                     

TP1              PA0
TP2              PA1
TP3              PA2
TP_ZENER         PA4
TP_REF           PA3
TP_BAT           PA5
TP_CAP           PA7

R_RL_1           PC0
R_RH_1           PC1
R_RL_2           PC2
R_RH_2           PC3
R_RL_3           PC4
R_RH_3           PC5

POWER_CTRL       PD7
TEST_BUTTON      PB2 
IR_DATA          PD3
ADJUST_RH        PC6
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 13, 2024, 05:53:14 pm
I have removed the Stc chip, and flashed m-firmware.
It is not working anymore, because the srv05 got damged, but i made some notes of the pinout.
The tester can work without SRV05, unless, of course, the microcontroller is also damaged.
You could provide the firmware so Feliciano can test it on his clone.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 2hry on February 13, 2024, 06:43:57 pm
I think the microcontroller is damaged.
It didnt start anymore and the srv05 got hot. So i removed it and the tvs, but it always measures a battery on pin2.

and compiled it in english again if anyone is interested.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 13, 2024, 07:37:41 pm
Indeed 2hry firmware worked, and as madires suggested, without further hardware modifications. Thank you very much dears.

Now my unit is running 1.51m (STC no longer needed, removed). And with the hints on the pin assigments, I will work on the original configs for customization.

FWIW (maybe for the clones files), attached a comparison of some clones' PCBs (JOYIT, FNIRSI on the right).

PS: It also looks to me that 2hry's MCU is damaged.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 13, 2024, 07:55:06 pm
Hello everyone,

Programmed my TT with version 1.51m and when I try to put it into L Monitor (inductance) it just stands on the screen in the photo and won't read anything and won't respond to the button press either.

What did I do wrong to not have it give my inductance readings?

Many thanks,

Raymond
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 14, 2024, 12:30:59 am
what version is this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 14, 2024, 03:24:32 am
what version is this?

You mean the Ttester, it is version ST7565R .
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 14, 2024, 05:32:19 am
Programmed my TT with version 1.51m and when I try to put it into L Monitor (inductance) it just stands on the screen in the photo and won't read anything and won't respond to the button press either.
Enable the RLC Monitor mode in the firmware. Will the tester in this mode react to the connection of resistance, capacitance, inductance?

Feliciano, To which ports of the ATmega324 were pins 7 and 8 of the STC connected? I've almost updated the circuit diagram for FNIRSI's LCR-TC1.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 14, 2024, 10:52:39 am
Your tester looks like my JOYIT T7.
I have removed the Stc chip, and flashed m-firmware.
It is not working anymore, because the srv05 got damged, but i made some notes of the pinout.

LCD_RES          PB4           
LCD_DC           PB3
LCD_SCL          PB7
LCD_SDA          PB5

Have you configured bit-bang SPI or hardware SPI? With that pin assignment hardware SPI should be possible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 14, 2024, 11:42:52 am
@madires: I don't know about the firmware binaries 2hry shared, but with 1.46m I enabled bitbang for the old TC1 (now I recall you said hardware SPI was not possible) and I did the same for the new one; and with 1.51m I got undefined function errors when trying to enable the default hardware SPI for the FNIRSI, so I choosed bitbang as well.
Sidenote: I'm using 1.46m now because the same set of features represent 99.7% usage on that, and 100.6% (32980B) on the other. I was planning to try intermediate versions, or perhaps you can suggest what to remove for this particular unit in order to save some Bytes.

@indman: the STC was connected to traditional PD1 and PD2. I attach the updated draft diagram for comparison.

Thank you both.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 14, 2024, 12:14:03 pm
Have you configured bit-bang SPI or hardware SPI? With that pin assignment hardware SPI should be possible.
On such a small display 1.8 we should not notice any difference in speed, or are there any other important factors that indicate the usefulness of hardware SPI?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 14, 2024, 12:36:06 pm
If code-wise hardware SPI would save some Bytes (vs software SPI), that alone would it be useful/worthy.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 14, 2024, 01:05:16 pm
Programmed my TT with version 1.51m and when I try to put it into L Monitor (inductance) it just stands on the screen in the photo and won't read anything and won't respond to the button press either.
Enable the RLC Monitor mode in the firmware. Will the tester in this mode react to the connection of resistance, capacitance, inductance?

Feliciano, To which ports of the ATmega324 were pins 7 and 8 of the STC connected? I've almost updated the circuit diagram for FNIRSI's LCR-TC1.

Hello Indman, when I enable RLC Monitor, tester reacts to resistance, capacitance perfectly, when I try to test an inductor, it gives me a resistance reading... Thank you for your help!
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 14, 2024, 01:10:56 pm
when I try to test an inductor, it gives me a resistance reading...
This means that the tester cannot determine the inductance because it is too small or its resistance is greater than 2 kOhm.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 14, 2024, 01:25:00 pm
Sidenote: I'm using 1.46m now because the same set of features represent 99.7% usage on that, and 100.6% (32980B) on the other. I was planning to try intermediate versions, or perhaps you can suggest what to remove for this particular unit in order to save some Bytes.

You could disable checks for rare components (SW_UJT, SW_SCHOTTKY_BJT).
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 14, 2024, 01:34:34 pm
On such a small display 1.8 we should not notice any difference in speed, or are there any other important factors that indicate the usefulness of hardware SPI?

A slightly smaller firmware size, as Feliciano already pointed out. And the most visible impact would be a faster screen clearing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 14, 2024, 02:28:32 pm
when I try to test an inductor, it gives me a resistance reading...
This means that the tester cannot determine the inductance because it is too small or its resistance is greater than 2 kOhm.

But whatever size I put it always gives me a resistance reading. Can it not read a 1uh 1R0 inductor ? These are inductors around a CPU on a motherboard. What is the range that it can read? Many thanks.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 14, 2024, 02:33:35 pm
rddube,The lower range of inductance measurements on m-firmware starts at about 10 microHenry. If you want to measure inductance values ​​lower than 10 microHenry, you can build an additional LC meter attachment or use the resonant method in k-firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 14, 2024, 02:46:35 pm
A slightly smaller firmware size
I'm for it. So let's do the 1.51m exercise again (32980B vs X) and please help me troubleshoot my configuration. I enabled
SPI_HARDWARE both on config and config_644, and disabled SPI_BITBANG on the first. I thought that would be enough for the Make, but I get the following errors:
Code: [Select]
SPI.c: In function 'SPI_Clock':
SPI.c:388:10: error: 'SPCR' undeclared (first use in this function)
   Bits = SPCR;                            /* get control register */
          ^
SPI.c:388:10: note: each undeclared identifier is reported only once for each function it appears in
SPI.c:389:19: error: 'SPR1' undeclared (first use in this function)
   Bits &= ~((1 << SPR1) | (1 << SPR0));   /* clear clock rate bits */
                   ^
SPI.c:389:33: error: 'SPR0' undeclared (first use in this function)
   Bits &= ~((1 << SPR1) | (1 << SPR0));   /* clear clock rate bits */
                                 ^
SPI.c:406:18: error: 'SPI2X' undeclared (first use in this function)
     Bits = (1 << SPI2X);           /* set bit to double SPI speed */
                  ^
SPI.c:409:3: error: 'SPSR' undeclared (first use in this function)
   SPSR = Bits;                     /* update register */
   ^
SPI.c: In function 'SPI_Setup':
SPI.c:444:3: error: 'SPCR' undeclared (first use in this function)
   SPCR = (1 << SPE) | (1 << MSTR);
   ^
SPI.c:444:16: error: 'SPE' undeclared (first use in this function)
   SPCR = (1 << SPE) | (1 << MSTR);
                ^
SPI.c:444:29: error: 'MSTR' undeclared (first use in this function)
   SPCR = (1 << SPE) | (1 << MSTR);
                             ^
SPI.c:450:10: error: 'SPSR' undeclared (first use in this function)
   Bits = SPSR;           /* read flag */
          ^
SPI.c:451:10: error: 'SPDR' undeclared (first use in this function)
   Bits = SPDR;           /* clear flag by reading data */
          ^
SPI.c: In function 'SPI_Write_Byte':
SPI.c:469:3: error: 'SPDR' undeclared (first use in this function)
   SPDR = Byte;                     /* start transmission */
   ^
SPI.c:470:12: error: 'SPSR' undeclared (first use in this function)
   while (!(SPSR & (1 << SPIF)));   /* wait for flag */
            ^
SPI.c:470:25: error: 'SPIF' undeclared (first use in this function)
   while (!(SPSR & (1 << SPIF)));   /* wait for flag */
                         ^
make.exe: *** [SPI.o] Error 1

> Process Exit Code: 2
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 14, 2024, 03:27:35 pm
If you enable SPI_HARDWARE in config_644.h you don't need to do that also in config.h (it will trigger a compiler warning). The error messages about undeclared register names could be caused by a missing header file. That should be avr/io.h (#include <avr/io.h> which is included in common.h). Try an additional #include <avr/io.h> in SPI.c.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 14, 2024, 03:48:04 pm
No joy with the suggested modifications. I post here the relevant sections:
Code: [Select]
*
 *  SPI bus
 *  - might be required by some hardware
 *  - could be enabled already in display section (config_<MCU>.h)
 *  - for bit-bang SPI port and pins see SPI_PORT (config_<MCU>.h)
 *  - hardware SPI uses automatically the proper MCU pins
 *  - uncomment either SPI_BITBANG or SPI_HARDWARE to enable
 */

//#define SPI_BITBANG                /* bit-bang SPI */
//#define SPI_HARDWARE               /* hardware SPI */
//#define SPI_RW                     /* enable SPI read support */
//#define SPI_SLOWDOWN               /* slow down bit-bang SPI */
Code: [Select]
/*
 *  ST7735
 *  - 4 wire SPI interface using hardware SPI
 */

//#if 0
#define LCD_ST7735                      /* display controller ST7735 */
#define LCD_GRAPHIC                     /* graphic display */
#define LCD_COLOR                       /* color display */
#define LCD_SPI                         /* SPI interface */
/* control and data lines */
#define LCD_PORT         PORTB          /* port data register */
#define LCD_DDR          DDRB           /* port data direction register */
#define LCD_RES          PB4            /* port pin used for /RESX (optional) */
//#define LCD_CS           PB?            /* port pin used for /CSX (optional) */
#define LCD_DC           PB3            /* port pin used for D/CX */
#define LCD_SCL          PB7            /* port pin used for SCL */
#define LCD_SDA          PB5            /* port pin used for SDA */
/* display settings */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       160            /* number of vertical dots */
#define LCD_OFFSET_X     2               /* enable x offset of 2 or 4 dots */
#define LCD_OFFSET_Y     1               /* enable y offset of 1 or 2 dots */
#define LCD_FLIP_X                      /* enable horizontal flip */
//#define LCD_FLIP_Y                      /* enable vertical flip */
#define LCD_ROTATE                      /* switch X and Y (rotate by 90°) */
//#define LCD_BGR                         /* reverse red and blue color channels */
#define LCD_LATE_ON                     /* turn on LCD after clearing it */
/* font and symbols: horizontally aligned & flipped */
#define FONT_10X16_HF                   /* 10x16 font */
//#define FONT_6X8_ISO8859_2_HF           /* 6x8 Central European font */
//#define FONT_8X8_ISO8859_2_HF           /* 8x8 Central European font */
//#define FONT_8X12T_ISO8859_2_HF         /* thin 8x12 Central European font */
//#define FONT_8X16_ISO8859_2_HF          /* 8x16 Central European font */
//#define FONT_10X16_ISO8859_2_HF         /* 10x16 Central European font */
//#define FONT_8X16_WIN1251_HF            /* 8x16 cyrillic font */
//#define FONT_8X16ALT_WIN1251_HF         /* 8x16 alternative cyrillic font */
#define SYMBOLS_30X32_HF                /* 30x32 symbols */
//#define SYMBOLS_30X32_ALT1_HF           /* 30x32 alternative symbols #1 */
//#define SYMBOLS_30X32_ALT2_HF           /* 30x32 alternative symbols #2 */
//#define SYMBOLS_32X32_HF                /* 32x32 symbols */
//#define SYMBOLS_32X32_ALT1_HF           /* 32x32 alternative symbols #1 */
//#define SYMBOLS_32X32_ALT2_HF           /* 32x32 alternative symbols #2 */
/* SPI bus */
#define SPI_HARDWARE                    /* hardware SPI */
//#endif
And as I said, it makes no difference to me to include or not the
Code: [Select]
#include <avr/io.h>
on SPI.c

I'm using WinAVR2010 with the replaced dll and toolchain over W10.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 14, 2024, 04:24:26 pm
On such a small display 1.8 we should not notice any difference in speed, or are there any other important factors that indicate the usefulness of hardware SPI?
A slightly smaller firmware size, as Feliciano already pointed out. And the most visible impact would be a faster screen clearing.
To my surprise, the size of the test firmware with SPI BitBung turned out to be smaller than SPI Hardware?!!!  ;D
Feliciano, check both test firmware on your clone and compare their behavior. Unless, of course, I made a mistake somewhere with the settings?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 14, 2024, 04:46:29 pm
indman, are you messing with me?  ;)

[EDIT] I found the error, it was the toolchain of my WinAVR. I can confirm that hardware SPI should be faster, but takes a little more memory on the m-firmware (33358B vs 33396B in my case). (Interesting, I got less memory usage with the other toolchain, but errors when trying to enable hardware SPI).


Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 14, 2024, 05:08:06 pm
indman, are you messing with me?  ;)
No, I didn’t even think about it! I have my own method for setting up configuration files, sorry.
I don’t like the 10x16 font at all, it looks awkward and it significantly increases the size of the firmware.
For ATMega328 and ATMega324 this is critical, so for clones with these controllers I only use the 8x16 font.
It’s strange that your firmware launched in Russian, because I chose English in the settings, this font supports the Latin alphabet.
Try 1 more firmware option from bitbung. Now I applied a 10x16 font and rotated the display orientation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 14, 2024, 05:23:43 pm
(I know you weren't messing with me, that was the wink for).
The new binaries work: correct orientation, and in continous mode. A callibration was needed out of the box, though. After that, it shows a 23V zener, because this unit only generates that much voltage. With DUT in place, it seems to work fine.

And about the bitmaps, we know bigger fonts means more memory, but for older eyes like mines is a trade-off. I haven't rendered the 8x16. By any chance do you have a side by side comparison against the 10x16 (small screen)? Is the 10x16 still the one I graphed on the attached?

I also noticed that more symbols were added to the bitmaps on recent versions of m-firmware, like battery icon, onewire, and maybe other stuff. I wonder whether those symbols are loaded into memory regardless whether we choose to display it or not? (I mean, whether the whole bitmap is loaded, or just the part of it we're declaring it's going to be used).

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 14, 2024, 05:38:45 pm
Feliciano, this was a test firmware, the rest of the nuances and fine settings must be chosen by the user himself. This doesn’t interest me much anymore, since I don’t have such a clone and I hope there won’t be one. The main thing is that we managed to adapt m-firmware in a relatively simple way. Say a big thank you again to madires, who provided very flexible port settings in the configuration files. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 14, 2024, 06:03:57 pm
To my surprise, the size of the test firmware with SPI BitBung turned out to be smaller than SPI Hardware?!!!  ;D

That's intriguing!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 14, 2024, 06:07:54 pm
Indeed.

I publically express my gratitude again to madires, for keeping this project going for so long, and keeping improving it on his free time, and to the other people here that help, like indman of course, and others (like 2hry in this case). And because I appreciate that, I also try to collaborate a little bit every now and then.

There are some question marks remaining for this other variant, like the probable hardware SPI support on such, but that's not a priority, I will give it another try at another moment.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 14, 2024, 06:15:43 pm
I also noticed that more symbols were added to the bitmaps on recent versions of m-firmware, like battery icon, onewire, and maybe other stuff. I wonder whether those symbols are loaded into memory regardless whether we choose to display it or not? (I mean, whether the whole bitmap is loaded, or just the part of it we're declaring it's going to be used).

If none of the display features requiring additional characters/symbols are enabled the additional characters/symbols aren't included in the firmware. The additional characters in the font bitmaps are the probe numbers with reversed colors and the battery icons. Addtional symbols are question mark, Zener diode, quartz crystal and one-wire.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 14, 2024, 06:24:57 pm
New GM328A  running 1.51m   I had to use Semi-ST7735, took me a great while to figure how, I came across a post searching here.

#if 1
//#define LCD_ST7735                      /* display controller ST7735 */
#define LCD_SEMI_ST7735                /* display controller SEMI ST7735 */

Attached is files changed

I could no get 16 Hz crystal working on this board, it messes with the display driver.
Title: Re: $20 LCR ESR Transistor checker project
Post by: YouCanDoIt on February 14, 2024, 08:15:32 pm
Sorry guys for disturbing the discussion, but I need your help to build a Mega 4gsl.
I found these two versions of the pcb (2022, 2019):
(https://img.radiokot.ru/files/96239/2z8221g6ku.jpg)
(https://img.radiokot.ru/files/96239/2z8221lxs9.jpg)
I only saw version 2015 developed from Nick Lanchak, the original author. Did he also released the above two versions?
I would like to use a color LCD, but the seller said that he only partially succeded. The output shows up, but very slowly (he said it is due to too high resolution). Plus there was a problem with the encoder, most likely the encoder needs to be transferred to other ports.
Someone can recommend a compatibile color LCD without such problems?

UPDATE
The tested screens with the above problems are ST7789v and ILI9341 on 1.48m. The board used is rev2023:
(https://img.radiokot.ru/files/96239/31lvftuk44.jpg)
Works fine with with LG12864E:
(https://img.radiokot.ru/files/96239/31k7tey4n6.jpg)
(https://img.radiokot.ru/files/96239/31k91goyvz.jpg)
(https://img.radiokot.ru/files/96239/32mc2fk89c.jpg)
I am wondering if the board revision plays a role.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rddube on February 14, 2024, 09:28:01 pm
rddube,The lower range of inductance measurements on m-firmware starts at about 10 microHenry. If you want to measure inductance values ​​lower than 10 microHenry, you can build an additional LC meter attachment or use the resonant method in k-firmware.

Thank you Indman for your reply and patience. I am relatively new at this and didn't know that the K firmware could support lower values of inductance. I have a TT with version 1.12K, is that good enough or is there a newer version and if so, where can i find it? I'd also like to read about the resonant method if you point me in the right direction. And again, thanks!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 15, 2024, 12:05:26 am
The last k-firmware version at the moment is 1.13k. You can find it, as well as the extense documentation (including measuring methods) at madires' github (https://github.com/madires/Transistortester-Warehouse/tree/master).
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 15, 2024, 03:45:44 am
Just received this one, with original ATmega328P. They are still out there.  ;)

https://www.aliexpress.com/item/1005005497252414.html?spm=a2g0o.order_list.order_list_main.5.52321802KA7hcS (https://www.aliexpress.com/item/1005005497252414.html?spm=a2g0o.order_list.order_list_main.5.52321802KA7hcS)

(https://ae01.alicdn.com/kf/S72f6a266164a48b39711e139f31f0810v.jpg)

That's the same one I been posting about.  here I show pictures how I connected and programed. both 1.3k and 1.51m  https://www.eevblog.com/forum/testgear/lastest-gm328a/msg5327048/#msg5327048 (https://www.eevblog.com/forum/testgear/lastest-gm328a/msg5327048/#msg5327048)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 15, 2024, 11:02:21 am
The last k-firmware version at the moment is 1.13k. You can find it, as well as the extense documentation (including measuring methods) at madires' github (https://github.com/madires/Transistortester-Warehouse/tree/master).

Just some snapshots. You'll find the latest k-firmware at https://github.com/kubi48/TransistorTester-source and its documentation at https://github.com/kubi48/TransistorTester-documentation.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 15, 2024, 11:55:24 am
Got it.

On the other hand, I was checking the 8x16-iso8859-2_hf font, and I corrected the uppercase O umlaut, and added some missing commas. Attached.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 15, 2024, 12:46:53 pm
Feliciano,here is the schematic diagram for your clone! Check if there are any gross errors in the arrangement of parts? ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 15, 2024, 01:38:58 pm
On the other hand, I was checking the 8x16-iso8859-2_hf font, and I corrected the uppercase O umlaut, and added some missing commas. Attached.

Thanks! The commas aren't missing because the last element of an array doesn't need one. A comma after the ç (c with cedilla) is added when FONT_EXTRA is defined (two lines below ç).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 15, 2024, 03:07:24 pm
indman, I modified the LCD and ISP connections. There are other minor errors, like the nunmbering of resistors (R20-pin19, R21-pin20, R22-pin21, R23-pin22, R17-pin23, R16-pin24, R14-pin4, and so on), although I understand that's not critical to fix (except for a newbie-intended documentation).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 15, 2024, 04:41:12 pm
Feliciano,Initially in the clone the LCD ports are assigned like this
#define LCD_DC           PB3            /* port pin used for D/CX */
#define LCD_SDA          PB5            /* port pin used for SDA */
Now what did you show in the last diagram?
#define LCD_SDA          PB3            /* port pin used for SDA */
#define LCD_DC           PB5            /* port pin used for D/CX */
Where is right?

And one more question - PB1(41pin) is connected to +5V through resistor R7. It is also directly connected to somewhere else through a via hole. Where?

I updated the circuit diagram for the FNIRSI clone in my previous post, taking into account corrections from Feliciano.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 15, 2024, 05:44:05 pm
Thanks for your concern. For sure it could be more errors lying around (and I could have made a mistake) as we are adapting one diagram to another. To help, I attach a high res. photo of the area of interest.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 15, 2024, 05:48:54 pm
Feliciano, I just updated the circuit diagram. I think that if there are errors or something is missing, then this is not too important. The main thing is that the thoughts of FNIRSI engineers remained in the fog!  ;D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 15, 2024, 05:53:06 pm
Yep. I'm glad and thankful we could sort this out  :). Now I can pass my old and trusty and improved WEI-M8 to a friend.

Another question: are we now using an small right-pointing-arrow instead of the ~ (the top part of the ñ) char.? I ask because I saw that on the 8x16-ISO8859-2_hf bitmap, and I might create a similar font for being able to keep with the m-firmware increasing code size.

BTW: I would prefer the show font feature on the m-firmware would do something like the attached picture, instead of the actual block and pages based format.
Title: Re: $20 LCR ESR Transistor checker project
Post by: BILLPOD on February 15, 2024, 06:11:14 pm
I bought one of the units on Amazon, (USA),...this one:  https://www.amazon.com/dp/B07WT9VVZB?psc=1&ref=ppx_pop_dt_b_product_details, (https://www.amazon.com/dp/B07WT9VVZB?psc=1&ref=ppx_pop_dt_b_product_details,) which describes the item as:
LCR-T4 Mega328 Digital Transistor Tester.    However, the MCU is an APT32F172K8T6.   It looks at an IGBT transistor and says it is a resistor.
I also hooked it to a UJT, (Unijunction Transistor), and it described it as a double diode.  And some of the FETS I connected it to were identified as plain old resistors.  I bought a T1 Transistor tester back in 2019 and it
identified all of these items accurately.   This new one is a piece of crap and I do not recommend that anyone waste their money on it.  If I find my old one, this one is going in the bin. :popcorn:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 15, 2024, 09:55:07 pm
Some remarks about the measurements with the new CTester running 1.51m, after measuring some components and callibrated profile:

EDIT: Similar high ESR measurements with indman's 1.51m, or with 1.46m.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 16, 2024, 02:48:08 pm
Some remarks about the measurements with the new CTester running 1.51m, after measuring some components and callibrated profile:
Examples of measuring capacitors on different firmware.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 16, 2024, 04:41:21 pm
Interesting: you are measuring the same capacitor on each CTester of each photo, right? because in each case the values are different, but on the same range, 'though. However, on the bottom right of the C100 photo it shows a value ten or twenty times higher than the others, like what I'm seeing now with 1.51m or 1.46m vs 1.13k.

So this (re)opens a new/old discussion: in the short term, the best known practice for configuration, to obtain a closer to reality value that gives us the idea on whether to replace or keep the DUT. And in the long term, whether there is something it could be optimized on the firmware

Note: We know that a real LCR Meter and a CTester use different methods for ESR assesment, but the difference is really high in some cases.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 17, 2024, 01:26:22 pm
For low value capacitors it's better to use an LCR/ESR meter to measure the ESR. The k-firmware does a better job than the m-firmware in that regard, but the measurement error increases as the capacitance value decreases (for both firmwares, Karl-Heinz' documentation tries to explain this). There's another observation. The measurement algorithm delivers ESR results comparable to a 10kHz test signal of an LCR meter. With low capacitance values the ESR results seem to be increasingly converging to the real frequency of the measurement algorithm. For example, the m-firmware measures an ESR of about 5 Ohms for a 100nF film cap. An LCR meter shows 1 Ohm @ 1 kHz and 15 Ohms @ 120Hz.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 17, 2024, 08:34:39 pm
I see, so in your opinion, the values currently measured by the m-firmware would be closer to the real life usage?
(For my use case, I normally work with switched power supplies).
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 18, 2024, 12:01:28 am
Got JLC making von Boleslaw J. (boleslaw_43) Adapter_328-644_106_quartzw  there still in production, takes like 2-3 weeks before I get them. they or 5 on a part, so 25 total!  anyone who want's one, there free for the taking (20) just pay shipping (self return stamped envelope) C1 100nf,  R1 680 ohm,  C2 C3 22p
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 18, 2024, 04:50:21 am
I see, so in your opinion, the values currently measured by the m-firmware would be closer to the real life usage?
(For my use case, I normally work with switched power supplies).
For electrolytic capacitors, the difference in ESR readings is minimal. For film ones, the k-firmware readings are closest. Shown in the previous message. For ceramic capacitors, see for yourself...
Title: Re: $20 LCR ESR Transistor checker project
Post by: willinsau on February 18, 2024, 05:19:19 am
It Looks Good. Someone will sell this?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 18, 2024, 12:12:33 pm
I suppose carl1961 is talking about a new version of the following adapter:
Adapter to upgrade the T-Tester with ATMEGA328 DIP28 to ATMEGA644 TQFP.
Idea and implementation by Boleslaw Jamroz from Poland,
I have only developed a circuit board for the cumbersome threading adapter
that simplifies the construction much ;-)
https://www.mikrocontroller.net/topic/transistortester-avr?goto=7398047#7381379 (https://www.mikrocontroller.net/topic/transistortester-avr?goto=7398047#7381379)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on February 18, 2024, 12:20:19 pm
I see, so in your opinion, the values currently measured by the m-firmware would be closer to the real life usage?

The ESR values for low capacitances match an AC test signal of around 600 Hz, while for higher capacitances it's roughly 10 kHz. However, it's about comparing ESR vales at the same test frequency. Let's say you're repairing a buck converter running at 250 kHz, but your LCR meter's highest test frequency is 100 kHz. So you have to stick with the 100 kHz and compare a possibly bad electrolytic to a good one at that frequency.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 18, 2024, 12:53:04 pm
Sure thing, but for my hobby I don't have a real LCR (high frequency) meter, so I'm using the pulse-train-based budget CTester clones (k-firmware, m-firmware) to get a rule of thumb on whether I shall replace or not a capacitor (most of times electrolitic for through-hole power supplies).

What got my attention is the tenfold difference estimation on each firmware branch, I haven't paid attention to that until know (as the modded m-firmware clones ran quickly from my hands). If you tell me you're trying to assimilate the values to those we would obtain from an LCR, that would be enough reasoning for me. But it you tell me "k-firmware does a better job on that regard" (moreover for lower capacitance, IIUC) I wonder why you chosed to go that path? Of course there should be reasons for that, but I also wonder why we would compromise for less accuracy if we know better, again, if that's the case.

Anyways, what about the Vloss and/or Iloss, if the values are accurate enough, we could judge based on that, or better on the the whole-picture, I suppose.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 18, 2024, 02:11:26 pm
I suppose carl1961 is talking about a new version of the following adapter:
Adapter to upgrade the T-Tester with ATMEGA328 DIP28 to ATMEGA644 TQFP.
Idea and implementation by Boleslaw Jamroz from Poland,
I have only developed a circuit board for the cumbersome threading adapter
that simplifies the construction much ;-)
https://www.mikrocontroller.net/topic/transistortester-avr?goto=7398047#7381379 (https://www.mikrocontroller.net/topic/transistortester-avr?goto=7398047#7381379)

Yes, he posted the grbl files for v106  the v108 is SMT crystal  page 32 along with the files for AY-AT   ComponentTester-1.51m_mod_files_for_AY-AT.zip  Page 31 for mega644_T7_AY_AT-Mod_v113k.zip  Lot's of good reading from the designers! a "must to read" to know better about these testers
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 18, 2024, 02:26:32 pm
Nice case for the Latest NON removable atmega328p  I don't recommend buying these, I already had them before I adventured here. Buy a AY-AT kit and the .1% resistor and better MCP1702 5V chip

https://grabcad.com/library/transistor-tester-gm328a-2
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 19, 2024, 12:45:54 pm
FWIW, I ran the ESR test through a series of film Capacitors. The trend seems logical to me, what I was discussing was the differences (including slightly different slope).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 20, 2024, 07:38:06 am
FWIW, I ran the ESR test through a series of film Capacitors. The trend seems logical to me, what I was discussing was the differences
At the beginning of the work on upgrading the k-firmware, I compiled similar graphs. I hoped to find the dependence of ESR on capacitance, but when analyzing different types and models of capacitors, I realized that the idea was a dead end. A larger capacitance may have a higher ESR value. Here is an example of measurements for capacitors of 1 µF and 0.47 µF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on February 20, 2024, 12:44:08 pm
Just got one of these:

https://www.ebay.com/itm/142849416622?var=441847192858 (https://www.ebay.com/itm/142849416622?var=441847192858)

Seems to be a new variant of the AY-AT board (8MHz) with Atmel chip. Once calibrated it is very accurate... surprisingly accurate if you ask!
Title: Re: $20 LCR ESR Transistor checker project
Post by: Messtechniker on February 20, 2024, 01:17:11 pm
It's always a good idea to have the micro socketed.
And a few spares around too. :horse:
Title: Re: $20 LCR ESR Transistor checker project
Post by: BILLPOD on February 20, 2024, 01:47:57 pm
Just got one of these:

https://www.ebay.com/itm/142849416622?var=441847192858 (https://www.ebay.com/itm/142849416622?var=441847192858)

Seems to be a new variant of the AY-AT board (8MHz) with Atmel chip. Once calibrated it is very accurate... surprisingly accurate if you ask!
That was the description of the one I got from Amazon, but mine has the ATP32F172K8T6 Chinese chip.   Same clear DIY case.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 20, 2024, 04:04:10 pm
At the beginning of the work on upgrading the k-firmware, I compiled similar graphs. I hoped to find the dependence of ESR on capacitance
I read some post you made about this topic on mid-2022, and I tried to retake that line to prove a)there's a relationship, and more important to me, b)the difference between k-firmware and m-firmware approach.

For the first test, I selected some Capacitors from the same vendor, same batch, same voltage range (63V-100V), and the results were very nice IMO. For the second test, I took a blind approach (like the practical scenario for the repair shop): different vendors, different ages, different voltages, so I expected high discrepancies, which in fact ocurred but not enough to discard the idea IMHO. I suppose if somebody repeat the exercise with same brand and voltage Capacitors, a more evident trend can be obtained. Lastly, I notice the measurements differences between k-firmware and m-firmware, the values are more similar for this escenario (being the m the more consistent), but the slope of m-firmware is higher, confirming the observations of the first test.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Calambres on February 20, 2024, 05:46:21 pm
Just got one of these:

https://www.ebay.com/itm/142849416622?var=441847192858 (https://www.ebay.com/itm/142849416622?var=441847192858)

Seems to be a new variant of the AY-AT board (8MHz) with Atmel chip. Once calibrated it is very accurate... surprisingly accurate if you ask!
That was the description of the one I got from Amazon, but mine has the ATP32F172K8T6 Chinese chip.   Same clear DIY case.

The kit includes 2% 1/8W resistors. I have checked them all and had to substitute some of them because they were beyond the 2% limit. I bet they're factory rejects to reduce costs...

The chip seems to be a legit ATMEL but nowadays who knows...

As I said in my previous port, once calibrated it is quite precise. I compared results with my DER DEE-5000 for resistors, capacitors and inductors and with my Peak Atlas DCA55 for semiconductors.
Title: Re: $20 LCR ESR Transistor checker project
Post by: SA on February 21, 2024, 05:17:35 pm
I fried my TC1 by charged capacitor. I have replaced the damaged components. The DIP MCU is also damaged. Is any firmware available for TC1 with atmega 328p? Attached picture is similar to my unit. I am not an expert, it would be great if there is hex file available.... :-+
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 22, 2024, 02:44:18 am
I fried my TC1 by charged capacitor. I have replaced the damaged components. The DIP MCU is also damaged. Is any firmware available for TC1 with atmega 328p? Attached picture is similar to my unit. I am not an expert, it would be great if there is hex file available.... :-+

Maybe start here, seems to be your model

https://www.eevblog.com/forum/testgear/tc1-lcr-meter-transistor-tester-fix/225/ (https://www.eevblog.com/forum/testgear/tc1-lcr-meter-transistor-tester-fix/225/)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 22, 2024, 09:26:28 am
Some types of film capacitors have specific frequency characteristics. For comparison, I showed these characteristics in comparison with the readings of the k-firmware. The points on the graphs correspond to frequencies of 1,5,10,20,40,60,80,100 kHz
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 22, 2024, 11:21:10 am
Absolutely, that's why is important -if we want to find trends- select same type of Capacitor, same Voltage range, and if possible, same vendor and batch (which I did for my first graph and not for the second).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 22, 2024, 03:01:37 pm
For low value capacitors it's better to use an LCR/ESR meter to measure the ESR.
I fully support that opinion. The use of a transistor tester to evaluate the quality of ceramic, film and other similar types is purely indicative and can very often misjudge such capacitors. There's no point in citing specs and graphs. It's easy enough to compare a few of the different types I listed above with a professional LCR meter to realize this. The difference between real ESR and tester readings can be 10-1000 times! Capacitance and ESR measurements a transistor tester are purely bonus in nature and are only good for monitoring ELECTROLYTIC capacitors. ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: rsjsouza on February 23, 2024, 02:08:56 am
I personally find the tan(delta) or D (dissipation factor) a more convenient measure, as it is independent on the capacitance. Also, given it is specified in the datasheets, it becomes a more certain method to evaluate the state of a capacitor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 23, 2024, 04:09:11 am
I personally find the tan(delta) or D (dissipation factor) a more convenient measure, as it is independent on the capacitance. 
Exactly, I agree with you, but unfortunately, this parameter can only be measured correctly by a full-fledged LCR meter.
The tester will not be able to do this.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 24, 2024, 07:55:29 am
Latest retirement Project, following  von Boleslaw J. great work, except the 2.8" TFT is in case with the AY-AT Board






Title: Re: $20 LCR ESR Transistor checker project
Post by: Boleslaw_J on February 24, 2024, 02:47:26 pm
Got JLC making von Boleslaw J. (boleslaw_43) Adapter_328-644_106_quartzw  there still in production, takes like 2-3 weeks before I get them. they or 5 on a part, so 25 total!  anyone who want's one, there free for the taking (20) just pay shipping (self return stamped envelope) C1 100uf,  R1 360 ohm,  C2 C3 22p

Should be C1 100 nF, R1 680 Ohm.

Well done! I like it. Powered by a rechargeable battery, charged via USB socket.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on February 24, 2024, 09:07:31 pm
Got JLC making von Boleslaw J. (boleslaw_43) Adapter_328-644_106_quartzw  there still in production, takes like 2-3 weeks before I get them. they or 5 on a part, so 25 total!  anyone who want's one, there free for the taking (20) just pay shipping (self return stamped envelope) C1 100uf,  R1 360 ohm,  C2 C3 22p

Should be C1 100 nF, R1 680 Ohm.

Well done! I like it. Powered by a rechargeable battery, charged via USB socket.


Thanks, I changed those values in the post.     soon as I verify the Enclosure Case I will share the stl and Cad Files
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on February 28, 2024, 09:03:32 pm
indman & Feliciano,
Thanks for the FNIRSI m-firmware adaptation. It works for my unit as well. (I left the STC in circuit)
If it's not too much trouble, can you post the source code which you used to compile the "LCR-TC1 FNIRSI 1.51mEn(SPI bitbang).zip" HEX & EEP files as per your earlier post? (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5334287/#msg5334287)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 28, 2024, 10:29:27 pm
If you want the binaries, indman shared some a few days back (I asume that's the one you're running?). He also has the more polished version of the schematic. 2hry also shared key configuration and binaries to help accelerate this development.

Nevertheless, if you want to adapt the code to you liking, my m-firmware device_specific configuration is:
Code: [Select]
MCU = atmega324p
FREQ = 16
PARTNO = m324pa
Code: [Select]
#define HW_ZENER
#define ZENER_R1         100000
#define ZENER_R2         12000
#define ZENER_UNSWITCHED
#define HW_PROBE_ZENER
#define ZENER_VOLTAGE_MIN     1000      /* min. voltage in mV */
#define ZENER_VOLTAGE_MAX     22000     /* max. voltage in mV */
#define HW_IR_RECEIVER
#define HW_ADJUST_CAP
#define BAT_DIRECT
#define BAT_OFFSET       0
Code: [Select]
#define LCD_PORT         PORTB          /* port data register */
#define LCD_DDR          DDRB           /* port data direction register */
#define LCD_RES          PB4            /* port pin used for /RESX (optional) */
#define LCD_DC           PB3            /* port pin used for D/CX */
#define LCD_SCL          PB7            /* port pin used for SCL */
#define LCD_SDA          PB5            /* port pin used for SDA */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       160            /* number of vertical dots */
#define LCD_OFFSET_X     2               /* enable x offset of 2 or 4 dots */
#define LCD_OFFSET_Y     1               /* enable y offset of 1 or 2 dots */
#define LCD_FLIP_X                      /* enable horizontal flip */
#define LCD_ROTATE                      /* switch X and Y (rotate by 90°) */

#define ADC_PORT         PORTA     /* port data register */
#define ADC_DDR          DDRA      /* port data direction register */
#define ADC_PIN          PINA      /* port input pins register */
#define TP1              PA0       /* test pin / probe #1 */
#define TP2              PA1       /* test pin / probe #2 */
#define TP3              PA2       /* test pin / probe #3 */

#define TP_ZENER         PA4       /* test pin for for Zener check (10:1 voltage divider) */
#define TP_REF           PA3       /* test pin for 2.5V reference and relay */
#define TP_BAT           PA5       /* test pin for battery (4:1 voltage divider) */
#define TP_CAP           PA7       /* test pin for self-adjustment cap */
#define R_PORT           PORTC     /* port data register */
#define R_DDR            DDRC      /* port data direction register */
#define R_RL_1           PC0       /* Rl (680R) for test pin #1 */
#define R_RH_1           PC1       /* Rh (470k) for test pin #1 */
#define R_RL_2           PC2       /* Rl (680R) for test pin #2 */
#define R_RH_2           PC3       /* Rh (470k) for test pin #2 */
#define R_RL_3           PC4       /* Rl (680R) for test pin #3 */
#define R_RH_3           PC5       /* Rh (470k) for test pin #3 */
#define POWER_PORT       PORTD     /* port data register */
#define POWER_DDR        DDRD      /* port data direction register */
#define POWER_CTRL       PD7       /* control pin (1: on / 0: off) */
#define BUTTON_PORT      PORTB     /* port data register */
#define BUTTON_DDR       DDRB      /* port data direction register */
#define BUTTON_PIN       PINB      /* port input pins register */
#define TEST_BUTTON      PB2       /* test/start push button (low active) */
#define IR_PORT          PORTD     /* port data register */
#define IR_DDR           DDRD      /* port data direction register */
#define IR_PIN           PIND      /* port input pins register */
#define IR_DATA          PD3       /* data signal */
#define ADJUST_PORT      PORTC     /* port data register */
#define ADJUST_DDR       DDRC      /* port data direction register */
#define ADJUST_RH        PC6       /* Rh (470k) for fixed cap */
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on February 29, 2024, 06:03:19 am
Feliciano,
Yes, I'm running the firmware uploaded by indman. (LCR-TC1 FNIRSI 1.51mEn(SPI bitbang).zip)
The schematic will be helpful as well so I've also saved a copy of that. Thanks.
One thing I did notice with this version is that there is a discrepancy in the capacitance measured depending on what mode it is operating in. Does your unit also show vastly different capacitance readings between "Probing..." mode and "LCR Monitor" mode for certain values? I did perform both a "Test" and an "Adjustment" thinking that was the issue but it wasn't. For example this is what I measured in uF:

Cap       "Auto"   "LCR mon"
1uF        1.039    1.038
10uF      9.929    9.953
39uF      36.29    37.02
120uF    99.79    120.1
270uF    155.6    262.5
680uF    328.3    599.5
1000uF  392.9    932.0
3900uF  3017     3657

Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 29, 2024, 06:21:38 am
Does your unit also show vastly different capacitance readings between "Probing..." mode and "LCR Monitor" mode for certain values? I did perform both a "Test" and an "Adjustment" thinking that was the issue but it wasn't.
No,there shouldn’t be such a big difference in the readings! It is not normal. I wonder what the results will be on the Feliciano clone?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on February 29, 2024, 08:34:11 am
Does your unit also show vastly different capacitance readings between "Probing..." mode and "LCR Monitor" mode for certain values? I did perform both a "Test" and an "Adjustment" thinking that was the issue but it wasn't.
I also have a difference in readings, but not so significant...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 29, 2024, 02:37:23 pm
I think something is not quite right with m-firmware for large Capacitors, at least for 1.51m, and for this new TC1 variant. Has somebody tried an older version?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 29, 2024, 03:42:30 pm
I think something is not quite right with m-firmware for large Capacitors, at least for 1.51m, and for this new TC1 variant. Has somebody tried an older version?
I think that the issue is not the new or old version of m-firmware, but the fact that your FNIRSI clone tests electrolytes completely differently from Kim Christensen. I think that there is some other hardware difference from the standard in these clones that does not allow the firmware to function normally. Or the firmware is not yet fully adapted.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 29, 2024, 04:27:36 pm
It could be either one: hardware or firmware. That's the thing to determine now. But the odd part here is that the failure seems to be LCR-Monitor specific, not normal DUT measurements  :-//

Regardless, one approach could be to check with older m-firmware, other it could be check your later schematic (could you please share it with me?) against the PCB and against the configuration files.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on February 29, 2024, 04:41:40 pm
Updated diagram in my post
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5335865/#msg5335865 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5335865/#msg5335865)
If you have the desire and time, then check again whether it corresponds to the real scheme of your clone?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 29, 2024, 05:39:23 pm
Actually I'm busy now, so maybe someone else wants to take the lead from here.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on February 29, 2024, 08:04:40 pm
I think that the issue is not the new or old version of m-firmware, but the fact that your FNIRSI clone tests electrolytes completely differently from Kim Christensen. I think that there is some other hardware difference from the standard in these clones that does not allow the firmware to function normally. Or the firmware is not yet fully adapted.

I assume the one on the right is Feliciano's unit:

(https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=2015498)


EDIT: Updated to better picture. Ignore the test loop wire.
From what I can see, it looks identical to mine. I'll do some double checking of the schematic against my unit:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on February 29, 2024, 08:33:50 pm
Yes, the one under study is the one the right. I also uploaded a high-res photo of the MCU and it's traces and external components (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5336444/#msg5336444), just in case.

Please also check the LCR-related configuration, because it seems the error is in that use-case, and with relative large capacitors.

UPDATE:
For my unit and 1.51m configuration, and for the LCR-Monitoring feature: Capacitors <22uF are quickly detected with reasonable values. Larger capacitors are either not detected or seldom detected as Inductors (normal measurements for those work properly, 'though).

Code: [Select]
#define SW_INDUCTOR
#define SW_ESR
//#define SW_OLD_ESR
#define SW_ESR_TOOL

#define SW_CAP_LEAKAGE
#define SW_MONITOR_RCL        /* R plus L, or C plus ESR */
//#define SW_MONITOR_HOLD_ESR   /* auto-hold ESR (C monitor) */
//#define SW_MONITOR_HOLD_L     /* auto-hold L (L monitor) */
#define SW_C_VLOSS
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 01, 2024, 04:26:30 am
Feliciano or indman,
What AVR toolchain are you using? Googling shows some old ones like WinAVR and then newer stuff like Microchip Studio. I've never programmed with AVRs. Just PICs and older stuff like 68HC11, etc so it's a bit of a learning curve.

Hardware wise:
On my unit, the 78L05 is dropping out of regulation since U6, the SDB628 boost reg, is only outputting 6.5V (R18/R19 sets it to a nominal 6.6V but tolerances give me a bit less). So the 5V line was fluctuating at around 4.8-4.9V. I temporarily bridged a 100K resistor across R19 which boosted the input voltage to the 78L05 to 7.1V... Then the 5V stabilized. While it didn't make any significant difference to the capacitance readings, I did notice that it effected the battery voltage readout which leads me to believe the firmware I'm using doesn't use the TL431 reference and instead uses the 5V supply as the reference.

I did notice an error on your schematic though:
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 01, 2024, 06:21:23 am
I did notice an error on your schematic though:
I will correct this inaccuracy on my schematic, but it's not essential. I'm more interested in what is the capacitance rating of C13 and C10 on your board?
And one more question - PB1(41pin) is connected to +5V through resistor R7. It is also directly connected to somewhere else through a via hole. Where?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 01, 2024, 11:23:21 am
Kim Christensen,Feliciano, check this new firmware for your clones. How will large capacitances be measured on it?
It would also be useful if you provided the results of hardware self-tests T1-T6 and self-correction tests A1-A6.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 01, 2024, 01:46:50 pm
What AVR toolchain are you using?
I'm ussing the original that came with WinAVR2010, because if I replace it with the one I used to use, it gave me errors when trying to enable hardware SPI (which we don't use for this case anyways).

Hardware wise:
On my unit, the 78L05 is dropping out of regulation since U6, the SDB628 boost reg, is only outputting 6.5V (R18/R19 sets it to a nominal 6.6V but tolerances give me a bit less). So the 5V line was fluctuating at around 4.8-4.9V. I temporarily bridged a 100K resistor across R19 which boosted the input voltage to the 78L05 to 7.1V... Then the 5V stabilized. While it didn't make any significant difference to the capacitance readings
I also noticed the same, the boost is giving me 6.xV, but the linear regulator seems to hold 5V (haven't had time to check thouroughly). I was considering reinforcing the boost capacitor (that was giving me trouble at the begining), but now you mention the resistor mod and its effects, I will consider it too.

I did notice that it effected the battery voltage readout which leads me to believe the firmware I'm using doesn't use the TL431 reference and instead uses the 5V supply as the reference.
IIUC, for Vref you can choose to read the TL431, or use the internal Vcc/2 of the ATmega (which I'm currently using):
Code: [Select]
/*
 *  2.5V voltage reference for Vcc check
 *  - default pin: PC4 (ATmega 328)
 *  - should be at least 10 times more precise than the voltage regulator
 *  - see TP_REF in config-<MCU>.h for port pin
 *  - uncomment to enable and also adjust UREF_25 below for your voltage
 *    reference
 */

//#define HW_REF25


/*
 *  Typical voltage of 2.5V voltage reference (in mV)
 *  - see datasheet of the voltage reference
 *  - or use >= 5.5 digit DMM to measure the voltage
 */

#define UREF_25           2495

#define TP_REF           PA3       /* test pin for 2.5V reference and relay */
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 01, 2024, 09:10:38 pm
Kim Christensen,Feliciano, check this new firmware for your clones. How will large capacitances be measured on it?
It would also be useful if you provided the results of hardware self-tests T1-T6 and self-correction tests A1-A6.

Thanks. I'll update my unit in a bit. Need to sort out my dodgy AVR programming hardware first. Was using AVRdude and ponyser, a serial port bit-banger which was glacially slow via a USB to serial adapter. I knew it would be slow trying to bitbang via USB-->Serial but it was much slower than I expected.  :palm:
Going to try an older computer that has a legacy serial port, but gotta get it up and running 1st.

Meanwhile, here the test results from the previous firmware you gave us. I'll post another test result after updating with your latest firmware:
Just ignore my nose/mouth reflection. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 01, 2024, 10:23:13 pm
I did notice an error on your schematic though:
I will correct this inaccuracy on my schematic, but it's not essential. I'm more interested in what is the capacitance rating of C13 and C10 on your board?
And one more question - PB1(41pin) is connected to +5V through resistor R7. It is also directly connected to somewhere else through a via hole. Where?
Besides what Kim Christensen reported earlier, R7 goes between pin 41 and Vcc. On that side of the PCB, pin 41 also goes to the tip of EN test point. Therefore, EN don't go to the Crystal array, that part of the schematic need rework. /Reset is pulled high by R14. And regarding C13 C10, it would have to be removed to be measured, because on circuit it detects a diode in both cases (and I ran some wires over it, so it would require extra work for my case). FWIW, with a DMM C13 measures 100nF or 470nF and I couldn't get a reading for C10.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 01, 2024, 11:54:41 pm
Kim Christensen,Feliciano, check this new firmware for your clones. How will large capacitances be measured on it?
It would also be useful if you provided the results of hardware self-tests T1-T6 and self-correction tests A1-A6.

Ah... So much faster/reliable using a legacy serial port.
OK, here's the updated capacitance readings. Looks pretty much the same as the last version:

Cap       "Auto"   "LCR mon"
1uF        1.083    1.079
10uF      10.35    10.33
39uF      37.75    38.35
120uF    103.6    124.6
270uF    162.0    272.9
680uF    342.2    625.6
1000uF  525.3    960.7
3900uF  3240     3790

I used the same capacitors as last time. Here's the previous readings for easy reference:
Cap       "Auto"   "LCR mon"
1uF        1.039    1.038
10uF      9.929    9.953
39uF      36.29    37.02
120uF    99.79    120.1
270uF    155.6    262.5
680uF    328.3    599.5
1000uF  392.9    932.0
3900uF  3017     3657

And the new self tests/corrections:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 02, 2024, 12:22:49 am
Kim Christensen,Feliciano, check this new firmware for your clones. How will large capacitances be measured on it?
It would also be useful if you provided the results of hardware self-tests T1-T6 and self-correction tests A1-A6.
Thanks. Your binaries probe there's something in the configuration that affects measurements of large capacitors (large meaning >22uF for my configuration).

As study subject I keep using the "SANYO" 1000uF/35V:

I attach the calibration and test results, with test leads.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 02, 2024, 12:45:07 am
I also noticed the same, the boost is giving me 6.xV, but the linear regulator seems to hold 5V (haven't had time to check thouroughly). I was considering reinforcing the boost capacitor (that was giving me trouble at the begining), but now you mention the resistor mod and its effects, I will consider it too.

Another option would be to replace the 78L05 with a 5V LDO regulator of the same pinout. The only negative I see with increasing the boost voltage, is reduced battery life as a bit more power is dissipated in the 5V linear reg, but it's the simplest of the options.
BTW, I measured the current draw off the battery at various voltages. Fluctuated at bit as it did it's thing:
3.10V = 155-200mA
3.80V = 120-150mA
4.14V = 107-132mA
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 02, 2024, 01:11:53 am
As by your measurements, I don't mind disipating additional 100mW or so as long as the equipment work properly.

(Perhaps a more precise schematic could help).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 02, 2024, 06:23:21 am
Besides what Kim Christensen reported earlier, R7 goes between pin 41 and Vcc. On that side of the PCB, pin 41 also goes to the tip of EN test point. Therefore, EN don't go to the Crystal array, that part of the schematic need rework. /Reset is pulled high by R14. And regarding C13 C10, it would have to be removed to be measured, because on circuit it detects a diode in both cases (and I ran some wires over it, so it would require extra work for my case). FWIW, with a DMM C13 measures 100nF or 470nF and I couldn't get a reading for C10.
OK! I updated the circuit diagram again, it remains to clarify where the PD0 (9pin) port of the controller is connected?
C13 - I believe that on your board it is set to 100nF. C10 should be 1nF, in principle it can be safely removed from the board, this should not affect the measurement results in original firmware. But it is advisable to check this!

And the new self tests/corrections:
The results of your tests indicate that the +5V voltage is poorly stabilized. You need to replace the 7805 with a better LDO.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on March 02, 2024, 07:17:15 am
From what I can see, it looks identical to mine. I'll do some double checking of the schematic against my unit:
Several years ago I assembled my testers on the ATMega 644. Now I don’t remember why, but I had to change some of the capacitance values. Here in your diagram I indicated my values...

Added. In the Hiland M644 C13, according to your circuit, the manufacturer initially installed 220nF.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 02, 2024, 02:25:19 pm
it remains to clarify where the PD0 (9pin) port of the controller is connected?
Pin 9 goes to RxD, pin 10 to TxD and pin 7 of U8. And the rest of U8 part of the schematic seems right.
C13 - I believe that on your board it is set to 100nF. C10 should be 1nF, in principle it can be safely removed from the board, this should not affect the measurement results in original firmware. But it is advisable to check this!
IIUC, C13 is the Capacitor used for Adjustement, and C10 is the bypass Capacitor of the Aref, right? Yuriy_K thinks these Capacitors should be higher, though.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 02, 2024, 04:32:49 pm
C13 is the Capacitor used for Adjustement ?
Yes, this capacitor must be high quality and stable. In the config.h setting, you can disable this installed capacity so as not to unsolder it from the board. Instead, you can use an external high quality capacitor for the Adjustement procedure. Then you will need to measure this capacity 3 times in a row before the Adjustement procedure.
C10 is the bypass Capacitor of the Aref, right?
C10 is the setting of the ADC voltage scale switching speed. For correct operation of autors firmware, its capacity should not exceed 1nF. As I wrote above, it can be removed from the board and this should not affect the test results in any way.

P.S The circuit diagram has been updated once again in my post #9226
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2024, 05:38:01 pm
One thing I did notice with this version is that there is a discrepancy in the capacitance measured depending on what mode it is operating in. Does your unit also show vastly different capacitance readings between "Probing..." mode and "LCR Monitor" mode for certain values? I did perform both a "Test" and an "Adjustment" thinking that was the issue but it wasn't. For example this is what I measured in uF:

Cap       "Auto"   "LCR mon"
1uF        1.039    1.038
10uF      9.929    9.953
39uF      36.29    37.02
120uF    99.79    120.1
270uF    155.6    262.5
680uF    328.3    599.5
1000uF  392.9    932.0
3900uF  3017     3657

There's something very wrong! The values in the normal probing cycle and in the C or RCL monitor should be nearly the same. For electrolytic caps a small difference (about 1%) is normal. This is caused by the different checks run in both modes before the capacitance measurement. Despite discharging and offset compensation a small charge difference can build up and lead to a small error. Anyway, both modes use exactly the same capacitance measurement functions. Your problem could be related to the power supply or some component drawing excessive current.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 02, 2024, 06:56:22 pm
madres,

If "both modes use exactly the same capacitance measurement functions", shouldn't they both give the same reading even if there was a hardware fault?
The readings are highly consistent and repeatable in both modes. So there must be some differences between the two measurement modes firmware wise, because code is the only thing that changes between modes.
My unit was working Ok with the original Chinese firmware, but that firmware had a bit of a bug where it wouldn't consistently measure ESR so I decided to try changing the firmware. ie: It would randomly give me vloss only and other times give both vloss and ESR.
In the end if I can't figure it out, I'm OK with just using my unit in LCR monitor mode when measuring capacitors. But it'd be nice if it worked properly in both modes.

Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 02, 2024, 07:13:55 pm
If "both modes use exactly the same capacitance measurement functions", shouldn't they both give the same reading even if there was a hardware fault?
The readings are highly consistent and repeatable in both modes. So there must be some differences between the two measurement modes firmware wise, because code is the only thing that changes between modes.
+1

madires:

As Kim says, if allegedly being the same algorithm for normal measurements and for LCR monitoring, I don't understand why the big inconsistence,

and on the other hand, why indman's configuration reflect way so different values than mine's for both scenarios. Maybe he set a very different compensation or default values? (because his readings varies a lot after adjustment, but still doesn't reach the expected values), and more important, why his LCR monitoring somehow works and mine doesn't.
Code: [Select]
#define CAP_FACTOR_SMALL      -25    /* -2.5% */
#define CAP_FACTOR_MID        -15    /* -1.5% */
#define CAP_FACTOR_LARGE      10     /* +1.0% */

Maybe Kim Chirstensen wants to try my attached binaries for a separate comparison.

Lastly, regarding the power supply, I modded the booster to 7V, and upgraded C9 from 100nF to 1uF.  For my config I didn't notice major difference. As shown in the photos versus my previous posts.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 02, 2024, 08:30:55 pm
Maybe Kim Chirstensen wants to try my attached binaries for a separate comparison.

Here's my results with your firmware. I had the same thing as you. Looks better in auto probing mode, but now LCR Monitor mode is messed up with larger caps:

Cap       "Auto"   "LCR mon"
1uF        1.054    1.053
10uF      10.64    10.64
39uF      42.48    -----
120uF    144.5    -----
270uF    312.7    -----
680uF    740.4    -----
1000uF  1144    8.36uH 0.0R
3900uF  5212     8.36uH 0.0R

----- = no reading

I also noticed that if I short the leads in LCR monitor mode, then it reads 0.05R 8.36uH.


Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 02, 2024, 08:57:23 pm
Anyway, both modes use exactly the same capacitance measurement functions.
You know the code better. Could it be the LCR monitor uses a particular pin that the normal testing function doesn't use, and we, or a least me defined it wrong?

Kim: Your equipment and mine behave the same. Have you tried the LCR monitor of 2hry firmware posted few pages back?
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2024, 09:11:41 pm
If "both modes use exactly the same capacitance measurement functions", shouldn't they both give the same reading even if there was a hardware fault?
The readings are highly consistent and repeatable in both modes. So there must be some differences between the two measurement modes firmware wise, because code is the only thing that changes between modes.

Again, the same capacitance measurement function is called in both cases. The only difference is the frontend function (user interface).

As Kim says, if allegedly being the same algorithm for normal measurements and for LCR monitoring, I don't understand why the big inconsistence,

Neither do I. It's the first time that such an issue is reported. I've checked a 1000µF electrolytic in normal probing mode, C monitor and  RCL monitor running 1.51m and the values are fine. I think there is something else wrong.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 02, 2024, 09:22:44 pm
You know the code better. Could it be the LCR monitor uses a particular pin that the normal testing function doesn't use, and we, or a least me defined it wrong?

The monitor functions use probes #1 and #3, You could check if the probe pins and the resistor pins are all correct and that there are no additional components (besides the input protection).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 02, 2024, 10:47:40 pm
I tried again 2hry's binaries, observing similar behaviour as indman's.

I also checked the configuration against the schematic, and seems correct. There is something else we're overlooking, or the schematic still doesn't match the PCB and/or values. (BTW: I think C26 is not on the PCB, the one near pin 17 is C8. Before modding, I measured a total of 600nF from Vcc to GND).

indman or 2hry: please compare my config against yours, so we can figure out why the same firmware work so different, and get the best of each settings. (Of course madires is welcome to have a look at it as well).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 02, 2024, 11:47:04 pm
Feliciano,
Was looking at the 1.51m source on GitHub (https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware), and noticed there was a change to the file "cap.c". I wonder if you are using the same "cap.c" file as indman and 2hry.
There are some differences (lines 881 onward) in the routine "LargeCap(Capacitor_Type *Cap)" that may explain why your routine behaves differently than theirs:

old 1.51 code:
Code: [Select]
    /* consider zero offset */
    if (U_Cap > U_Zero)            /* voltage higher than zero offset */
      U_Cap -= U_Zero;                  /* subtract zero offset */
    else                           /* shouldn't happen but you never know */
      U_Cap = 0;                        /* assume 0V */

new 1.51 code:
Code: [Select]
    /* consider zero offset */
    U_temp = (int16_t)U_Cap;       /* explicit type conversion */
    if (U_temp > U_Zero)           /* voltage higher than zero offset */
      U_temp -= U_Zero;                 /* subtract zero offset */
    else                           /* shouldn't happen but you never know */
      U_temp = 0;                       /* assume 0V */
    U_Cap = (uint16_t)U_temp;      /* take result */

There may be other differences, but it's interesting that the differences are in the LargeCap routine...
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 12:48:59 am
Hmmm. I wasn't aware of that. According to your observations, the 1.51m I downloaded from github is the old one, from december I think.

UPDATE:
I applied my same configuration to 1.46m, and I get 997uF under normal mode, and 955uF under RCL monitoring, which seems a lot better, but makes me wonder there could be something in the code. I will try 1.48m tomorrow and report.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on March 03, 2024, 01:21:07 am
Hmmm. I wasn't aware of that. According to your observations, the 1.51m I downloaded from github is the old one, from december I think.

UPDATE:
I applied my same configuration to 1.46m, and I get 997uF under normal mode, and 955uF under RCL monitoring, which seems a lot better, but makes me wonder there could be something in the code. I will try 1.48m tomorrow and report.

in the firmware folder is the fixed cap.c

Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 01:28:44 am
yes, I know. I opened the 1.51m and found the code you mention, but around line 955:
Code: [Select]
    /* consider zero offset */
    if (U_Cap > U_Zero)            /* voltage higher than zero offset */
      U_Cap -= U_Zero;                  /* subtract zero offset */
    else                           /* shouldn't happen but you never know */
      U_Cap = 0;                        /* assume 0V */

    /* end loop if charging is too slow */
    if ((Pulses == 126) && (U_Cap < 75)) TempByte = 0;
   
    /* end loop if 300mV are reached */
    if (U_Cap >= 300) TempByte = 0;
And the file modification date is dec 2nd, 2023.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 01:35:55 am
I have backported my 1.51m config to 1.48m, and it shows a capacitor close to the expected value either under normal measurement or RCL monitoring. Therefore something on the code and/or the configuration is messing my 1.51m. I can try to download and customize 1.50m tomorrow to confirm/discard.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on March 03, 2024, 01:36:31 am
yes, I know. I opened the 1.51m and found the code you mention, but around line 955:
Code: [Select]
    /* consider zero offset */
    if (U_Cap > U_Zero)            /* voltage higher than zero offset */
      U_Cap -= U_Zero;                  /* subtract zero offset */
    else                           /* shouldn't happen but you never know */
      U_Cap = 0;                        /* assume 0V */

    /* end loop if charging is too slow */
    if ((Pulses == 126) && (U_Cap < 75)) TempByte = 0;
   
    /* end loop if 300mV are reached */
    if (U_Cap >= 300) TempByte = 0;
And the file modification date is dec 2nd, 2023.

Yes around  time of madires post

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5234115/#msg5234115 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5234115/#msg5234115)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 03, 2024, 05:54:28 am
Kim: Your equipment and mine behave the same. Have you tried the LCR monitor of 2hry firmware posted few pages back?

I guess I shouldn't have skipped that one, since 2hry's capacitor functions do work in both "auto probe" and "c-monitor" modes:

Cap       "Auto"   "C mon"
1uF        1.086    1.079
10uF      10.44    10.40
39uF      41.88    41.60
120uF    130.1    126.8
270uF    285.3    274.7
680uF    674.5    649.6
1000uF  1046     999.1
3900uF  4765     4688
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 03, 2024, 06:14:06 am
I guess I shouldn't have skipped that one, since 2hry's capacitor functions do work in both "auto probe" and "c-monitor" modes:
What m-firmware version number is shown on the start screen in this firmware?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 03, 2024, 06:20:30 am
v1.51m

EDIT: Though 2hry's menu item says, "C monitor" (it doesn't measure inductance) instead of "LCR monitor" like in yours and Feliciano's.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 03, 2024, 07:43:07 am
Ok! In order not to be completely confused about the reasons for this behavior I suggest to calm down a bit, think and start testing again.
I will compile 2 firmware versions with the same configuration file settings, 1.50m and 1.51m. They will include all possible monitoring options - RCL monitor, L-monitor, C-monitor. And you check and compare the behavior of your clone in these modes and AUTO mode. Is that okay with you? :)

Test firmware 1.50mEn and 1.51mEn for FNIRSI LCR-TC1 clone. The configuration files are in the archive.
Title: Re: $20 LCR ESR Transistor checker project
Post by: 2hry on March 03, 2024, 12:10:51 pm
I can not confirm this behavior on my T7 tester with 1.51.
Which is now modified because i have destroyed my adc inputs PA1,2 and 3(the reference???how did i do that).
Now i´m testing on PA0 PA6 and PA7, to which i botched 2 wires.
Lifted the broken pins of the atmega, and removed the TP_CAP.
So I dont have the reference on PA3, and the TP_Cap on PA7 anymore.

To compile, I downloaded the sources from Transistortester-warehouse, and changed the cap.c which is in an extra folder. Then only updated the pins for my tester, and the resistor divider for the zener test. (the cap factors are unchanged)

I have tried different options in config.h, but it is working as expected in normal and LCR mode.

What i did change earlier, are the 680R and 470K resistors.

Indmans schematic looks complete to me, except(as Feliciano pointed out)
 C26 is not on the PCB, and C8 near pin 17. 

Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 01:21:43 pm
Tried indman's new builds, with the same 1000uF subject, configured for -1% of compensation for this range, and adjusted:

1.50m (ignoring the first measurement in each case):
Notice there are some uF of variance for consecutive measurements. The repetitiveness of measurements have been already addressed: We know this is not a medium-high precision instrument, so I don't complaint.

1.51m (ignoring the first measurement in each case):

I think these results are acceptable, and maybe it can be fine-tuned with compensation for each of the 3 ranges. Still, there's some difference between normal mode and monitoring mode. Being the same algorithm, I don't see the reason.

What I'll do next is to backport my 1.51m config to 1.50m, because it works fine with older m-firmware (i.e. 1.46m and 1.48m) but screws 1.51m monitoring mode.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 03, 2024, 01:30:53 pm
Feliciano,Now your clone shows adequate results on both firmware versions.
You should not expect from a simple tester that the measured capacity will exactly match what is written on the marking (I think these are truisms and there is no need to further explain the reasons).
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 03, 2024, 01:42:17 pm
I think these results are acceptable, and maybe it can be fine-tuned with compensation for each of the 3 ranges. Still, there's some difference between normal mode and monitoring mode. Being the same algorithm, I don't see the reason.
Yes, they can be easily adjusted if necessary!
As for the difference when measuring capacitance in AUTO mode and monitor mode, madires has already explained this behavior earlier, and also made a note in the manual(hint). I also think that the slight difference in results is most likely due to the fact that AUTO mode involves a lot more preliminary checks and steps before measuring capacitance. And in monitor mode, the algorithm is immediately configured to measure a certain parameter. But it is a little surprising that the first measurement in monitor mode is always very close to the value obtained in AUTO mode, but then decreases.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 02:43:47 pm
Yes, I mostly agree with you. I'm only elaborating because this is a public discussion, and different readers are at different levels.

Anyways, I backported my 1.51m to 1.50m, and it works, so something on my configuration or my build environment breaks 1.51m monitoring. At least now we know is something like that, and it will require further reviewing.

Regarding my measurements, Normally the first value is higher than expected, the second lower, and then the others are intermediate.

Just for reference, my 1000uF on 1.50m, with my same settings, measures:

I also noticed that if I short the leads in LCR monitor mode, then it reads 0.05R 8.36uH.
And a short is still measured as 8uH on both modes.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 03, 2024, 04:03:48 pm
Yes, I mostly agree with you. I'm only elaborating because this is a public discussion, and different readers are at different levels.
This is true, but nevertheless, if a person is involved in amateur radio and he needs this device not only as a beautiful toy, then he must have basic knowledge and concepts in electronics. And it's never too late to learn ;)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 05:02:19 pm
We agree again.

To rule-out my W10 build environment, I took indman's config and made 1.51m, with the result of LCR monitoring broken too. So it's not my config files, it's my setup. Hence I ask:
indman, what toolchain are you using?
With the default toolchain of WinAVR-20100110, I can build a hardware SPI (which we don't use for this), but I cannot make your config files fit (105% vs your 99.6%), and the LCR monitoring gets broken on 1.51m -but not on olders-.
And with the avr8-gnu-toolchain-installer-3.5.1.87 I cannot make a hardware SPI (the compilation errors I reported before).

It may be related with:
Quote
v1.51m 2023-12
- Changed GetThirdProbe() into convenience function UpdateProbes2() to reduce firmware size and adapted calls in various other functions (suggested by Viktor Klimkovich).
- Optimized DataStorage() and ManageAdjustmentStorage() to reduce firmware size (thanks to Viktor Klimkovich).
- Added option to slow down bit-bang SPI in case of a high MCU clock rate (SPI_SLOWDOWN, suggested by Viktor Klimkovich).
- Changed calculation of delay loop in IR_Detector() to support MCU overclocking (thanks to Viktor Klimkovich).
- Improved voltage drop algorithm in function LargeCap().
- Function LargeCap() takes now also negative zero offset into account.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 03, 2024, 05:09:16 pm
Feliciano, I am using WinAVR-20100110 + AVR-GCC 8.3.0.
Use the search, not so long ago in this thread we discussed the most favorable combination of software for compilation to get a compact firmware size.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 05:38:19 pm
Thanks, I remember that discussion (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5048659/#msg5048659), but the conclusion was not clear to me.

I'm trying now that toolchain, downloaded from ZakKemble's github, but it gives me compile errors. I'm troubleshooting what it is.
Code: [Select]
avr-size: invalid option -- C
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 03, 2024, 05:42:43 pm
While you are figuring out how to install the software, you can give me your customized configuration files and font, I will compile the 1.51m firmware for you.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 03, 2024, 05:42:52 pm
To rule-out my W10 build environment, I took indman's config and made 1.51m, with the result of LCR monitoring broken too. So it's not my config files, it's my system. Hence I ask:

Have you replaced the 1.51m's cap.c file with the fixed one (repo: cap.c-1.51m.tgz)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 05:52:09 pm
As a little give-back to the project, here I present an alternate 8x16 hf western font. I composed it to be heavier and less serif than the existing one, and shifted a bit to the right, so I hope it gets better readability overall.

It's my first font from scratch, so please check it before adding to upcoming releases.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 06:01:03 pm
Have you replaced the 1.51m's cap.c file with the fixed one (repo: cap.c-1.51m.tgz)?
No, but I can fetch it an try again, once I fix the actual 8.3.0 toolchain incompatibility with the WinAVR2010.

In the meantime, I posted my config files on a previous message (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5368643/#msg5368643), and the custom font is on the previous post. So if somebody can build the binaries we can pinpoint the abnormal C monitoring differences bug. But me must note whether is with the december's cap.c or the current one.


EDIT:
I fixed the toolchain incompatibility, and made 1.51m with the old cap.c and with the new cap.c. And I can confirm now the monitoring bug can be specifically related to 1.51m and the old cap.c.

Special thanks to indman, and also Kim Christensen, 2hry and madires for the support.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 03, 2024, 06:28:43 pm
Feliciano, I'm glad you're over the problem!  :)
 I compiled the firmware with your font, it's in the archive.
There were a few errors in your config.h file, I fixed them. I also believe that for your clone, a correction of 0(-1%) for large capacitances is optimal. If you set +1.0, the tester will overestimate the capacitance on large capacitors, for example 4700.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 06:49:07 pm
Tried last indman's build.

And thinking about the compensation, I went to the other extreme, and tried a very large capacitor. I couldn't get a reading in this case: maybe the timeout for LCR monitoring is a tad short?

Note: I will check config's differences later.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 03, 2024, 06:53:49 pm
And thinking about the compensation, I went to the other extreme, and tried a very large capacitor. I couldn't get a reading in this case: maybe the timeout for LCR monitoring is a tad short?
This is already interesting! I have not tested such large capacities in monitor mode. Tomorrow I'll check it on my clones. :D
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 03, 2024, 08:49:06 pm
Tried last indman's build.
And thinking about the compensation, I went to the other extreme, and tried a very large capacitor. I couldn't get a reading in this case: maybe the timeout for LCR monitoring is a tad short?
Note: I will check config's differences later.

I tried a 10,000uF and it worked in both modes with the "1.51mEn(8x16)Feliciano firmware". (Read as 11.78mF)
Then I paralleled another 8,200uF and it continued to work in both modes.  (Read as 19.6mF)
Crammed another 3900uF.   (Read as 26.19mF)
Note: My jumper wires did add some extra "ESR" and these, except for the 3900uF, were used parts...

Not sure what the point of your "ESR" test mode is, since it only works with capacitors... ie: RCL monitor does that already. Speed?

Feliciano, I am using WinAVR-20100110 + AVR-GCC 8.3.0.
Use the search, not so long ago in this thread we discussed the most favorable combination of software for compilation to get a compact firmware size.

Thanks. I'll try this instead of continuing with the "whack a mole" compiler error game that I'm currently playing... (Bit of a C compiler noob here, so the binaries and config files are a godsend)
FYI, the "FNIRSI 1.51mEnTestMonitor" binaries also worked fine with my unit in all modes.

EDIT on Mar 5th, 2024:
Here are the changes I made to my ComponentTester-1.51m code's makefile so it compiles using WinAVR-20100110 and AVR-GCC 8.3.0 and works on the TC-1 (FNIRSI-4A10 version) tester.
The LDFLAGS makes the code smaller so it'll fit.
"avr-size" is no longer supported and gave errors, so that line was commented out and "avr-objdump" was added instead.

MCU = atmega324p
FREQ = 16
LDFLAGS += -Wl,-relax
#   @avr-size -C --mcu=${MCU} $<
   @avr-objdump -Pmem-usage ${NAME}

See attached makefile which includes the above changes:
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 03, 2024, 09:48:14 pm
Not sure what the point of your "ESR" test mode is, since it only works with capacitors... ie: RCL monitor does that already. Speed?
From the manual:
Quote
The ESR tool measures capacitors in-circuit and displays the capacity and ESR if the measurement detects a valid capacitor. Make sure that the capacitor is discharged before connecting the tester! Values could differ from the standard measurement (out-of-circuit) because any component in parallel with the capacitor will affect the measurement.

Note: My jumper wires did add some extra "ESR"
That's why we have the "Adjustement" and "Save" for. In my case, I use the two connection methods by turns, so that's why I select the saved profile at the begining, but other people can prefer to adjust and not to save.

(Bit of a C compiler noob here, so the binaries and config files are a godsend)
From my part, a pleasure to help, and contribute a bit to the developement. And I think we also shall thank indman and the other people for helping support this clone variant, and ironing the code (either with the "say thanks" button, or in written).

BTW: I increased the cycle time, and now I can detect a 22mF. I suppose if we increase it more we could detect larger capacitors (like 44mF), but it would become a trade off on waiting when measuring "normal" values on regular basis.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 04, 2024, 04:24:28 pm
As a little give-back to the project, here I present an alternate 8x16 hf western font. I composed it to be heavier and less serif than the existing one, and shifted a bit to the right, so I hope it gets better readability overall.

It's my first font from scratch, so please check it before adding to upcoming releases.

Thanks! I've corrected the index addresses for the additional characters and removed a comma.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 04, 2024, 05:39:19 pm
Thanks. I updated my original post for further readers.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on March 05, 2024, 03:47:46 am
For who may want this  ;) a alternative for WinAVR     Transistor-Tester-AVR-Compiled-files-On-Windows
Mainly did this so later when i forget how.

also the github link where anyone can fork and improve.

https://github.com/carl1961/Transistor-Tester-AVR-Compiled-files-On-Windows

Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on March 05, 2024, 03:56:00 am
Got the 644 Adapter board in today.. Now the fun begins. Remember anyone who wants one, there free for what a stamp and envelope cost.

Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on March 05, 2024, 09:51:12 am
Got the Board soldered and Programmed, having trouble with the 2.8 TFT
The firmware right now is von Boleslaw J. (boleslaw_43) pre compiled Adapter_m328_m644_AY-AT_mod_hard_SPI_firmware 1.49m
@indman can you have share how you connected the 2.8 TFT to AH-AT?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on March 05, 2024, 10:44:43 am
can you have share how you connected the 2.8 TFT to AH-AT?
Look at the message and at the fragment of the diagram...
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4882043/#msg4882043 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4882043/#msg4882043)

The link works
Title: Re: $20 LCR ESR Transistor checker project
Post by: Boleslaw_J on March 05, 2024, 11:10:25 am
Got the Board soldered and Programmed, having trouble ...

In order for the microcontroller to work with an external crystal
resonator, the microcontroller's fuses must be properly positioned.
When programming these keys, an external resonator (e.g. 8 or 16 MHz) must be
connected to the microcontroller!

Valid key values are:
Fuses:
L: 0xF7
H: 0xD9
E: 0xFC

Lock bits:
LB: 0xFF  (do not touch!)

Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on March 05, 2024, 11:33:59 am
Got the Board soldered and Programmed, having trouble ...

In order for the microcontroller to work with an external crystal
resonator, the microcontroller's fuses must be properly positioned.
When programming these keys, an external resonator (e.g. 8 or 16 MHz) must be
connected to the microcontroller!

Valid key values are:
Fuses:
L: 0xF7
H: 0xD9
E: 0xFC

Lock bits:
LB: 0xFF  (do not touch!)
Thanks Boleslaw_J ,

I already have a 16 MHZ Crystal on the main board, that's why the crystal is missing from your  644 Adapter. Do i need to remove it and install on adapter? I under stood to leave it off the crystal from Adapter if already have one on the board.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Boleslaw_J on March 05, 2024, 12:26:09 pm
Thanks Boleslaw_J ,

I already have a 16 MHZ Crystal on the main board, that's why the crystal is missing from your  644 Adapter. Do i need to remove it and install on adapter?

Of course not. The location of the external resonator is not important.




Title: Re: $20 LCR ESR Transistor checker project
Post by: Boleslaw_J on March 05, 2024, 03:53:26 pm
@ carl1961

The current used 2.8-inch 240x320 LCD TFT displays with ILI9341 or ST7789 drivers are powered by 3.3 V. To connect them to the AY-AT tester, whose microcontroller is powered by 5 volts, an additional interface must be used to reduce the voltage level.
Here is an example of such an interface.


Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on March 05, 2024, 05:51:54 pm
Thanks Boleslaw_J ,

I already have a 16 MHZ Crystal on the main board, that's why the crystal is missing from your  644 Adapter. Do i need to remove it and install on adapter?

Of course not. The location of the external resonator is not important.
Thanks  Boleslaw_J,  that's what I read from your post  ;)  https://www.mikrocontroller.net/topic/transistortester-avr?page=32#7426316 (https://www.mikrocontroller.net/topic/transistortester-avr?page=32#7426316)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 06, 2024, 11:59:30 pm
Dear madires:
I'm still working, with low priority, on the fonts.

IIRC, Karl-Heinz used to show the test of the bitmaps continously as it fit the screen (reminds me a typewriter). You on the other hand plot 8 chars per line. Because there is the case of small and/or narrow fonts on a high_res LCD (like 8x16 on 160128), I wonder whether it would take too much code to do something like:
if((screen_witdh/font_width>17);then plot_16_char_per_row;else plot_8_char_per_row /*as done now*/)
That way we would have to scroll less, and get a better understanding of the whole set.

What do you think?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Boleslaw_J on March 07, 2024, 07:41:26 am
Thanks Boleslaw_J ,
I already have a 16 MHZ Crystal on the main board, that's why the crystal is missing from your  644 Adapter. Do i need to remove it and install on adapter?

Of course not. The location of the external resonator is not important.
Thanks  Boleslaw_J,  that's what I read from your post  ;)  https://www.mikrocontroller.net/topic/transistortester-avr?page=32#7426316 (https://www.mikrocontroller.net/topic/transistortester-avr?page=32#7426316)

If you want to know exactly what I meant, check out the content of the post I wrote earlier on the subject:
https://www.mikrocontroller.net/topic/transistortester-avr?page=31#7396852 (https://www.mikrocontroller.net/topic/transistortester-avr?page=31#7396852)
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 07, 2024, 08:53:50 am
IIRC, Karl-Heinz used to show the test of the bitmaps continously as it fit the screen (reminds me a typewriter). You on the other hand plot 8 chars per line. Because there is the case of small and/or narrow fonts on a high_res LCD (like 8x16 on 160128), I wonder whether it would take too much code to do something like:
if((screen_witdh/font_width>17);then plot_16_char_per_row;else plot_8_char_per_row /*as done now*/)
That way we would have to scroll less, and get a better understanding of the whole set.

A similar suggestion was already on my to-do list (implemented a few days ago). The alternative output prints all available characters without an index address and uses the complete display width.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strateg58 on March 08, 2024, 05:23:56 am
Hi guys. Which one of you has implemented the LOPT/FBT function in the transistor tester.? It doesn't work for me. See if I have connected the circuit correctly. [attachimg=1]
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 08, 2024, 09:13:32 am
It seems that Vcc and Gnd are reversed. From the README:
Code: [Select]
Pinout for control output via probes:
  Probe #1:  Vcc (5 V)
  Probe #2:  pulse output (with 680 Ohms resistor to limit current)
  Probe #3:  Ground
  T0:        counter input
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strateg58 on March 09, 2024, 03:48:08 am
Thanks Madires. And to connect to +5 volts, or is it enough to connect to Pin1
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on March 09, 2024, 06:11:12 am
Finally got AY-AT Running, with von Boleslaw J. (boleslaw_43) Adapter_m328_m644_AY-AT. made a adapter from His photo FotoAlbum_TT_diagram. attached is eagle cad of the adapter and the kicad version to CNC mill, putting 4 jumpers (green traces) on back, because I can only do one sided PCB's.  I forgot to mirror the board , when doing the Milling file gcodes and had to solder the chip directly  to pcb (or redo it). Now to make small cables for screen and tweak the Case. 
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 09, 2024, 10:51:04 am
Thanks Madires. And to connect to +5 volts, or is it enough to connect to Pin1

Probe #1 is fine.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rogerdammit on March 10, 2024, 05:34:44 pm
Thanks, I remember that discussion (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5048659/#msg5048659), but the conclusion was not clear to me.

I'm trying now that toolchain, downloaded from ZakKemble's github, but it gives me compile errors. I'm troubleshooting what it is.
Code: [Select]
avr-size: invalid option -- C

I'm getting the same error. Can you please post the fix?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 10, 2024, 06:28:25 pm
I rolled back to the original avr-size.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 10, 2024, 08:08:15 pm
Thanks, I remember that discussion (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5048659/#msg5048659), but the conclusion was not clear to me.

I'm trying now that toolchain, downloaded from ZakKemble's github, but it gives me compile errors. I'm troubleshooting what it is.
Code: [Select]
avr-size: invalid option -- C

I'm getting the same error. Can you please post the fix?

I made the following changes to my makefile:

#   @avr-size -C --mcu=${MCU} $<
   @avr-objdump -Pmem-usage ${NAME}

Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on March 10, 2024, 08:55:36 pm
Signing off with this Project, It was fun.  :-DMM
Attached firmware is using the 74HC4050AP Adapter posted on my last post.
Title: Re: $20 LCR ESR Transistor checker project
Post by: carl1961 on March 10, 2024, 08:58:08 pm
STL file for case and pictures of testing
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 11, 2024, 03:43:01 pm
It's my understanding that after pondering pros and cons, the Sampling ADC development has been put on hold for m-firmware. So looking at the quartz crystal measurement options for this, I have some comments about the documentation:
Section 3.1.12. Frequency Counter of CTester 1.51m doc points: "The circuit diagrams for both are depicted in Karl-Heinz’ documentation."
However, on TTester 1.13k (2021) doc I notice the basic frequency measurement circuit, but not what referred from 1.51m doc.
And back to 1.51m doc, I think 3.1.13 and 3.1.14 are both the options of 3.1.12, so IMHO those should be 3.1.12.1 and 3.1.12.2.

Anyways, I looked at the schematic of the Hiland M644, and I notice the implemented (extended) hardware option. Could that be ported to an smaller MCU?
It's not like I'm testing xtals everyday, but anyways I know the workaround: to have k-firmware handy.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 11, 2024, 05:26:24 pm
The extended frequency counter is part of the extended Transistor Tester circuit with ATmega644 shown in Karl-Heinz' documentation (Figure 2.16.). I think it should be possible to use an ATmega328 with an I2C display to free up three I/O pins to control the frequency counter frontend.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 12, 2024, 06:47:44 am
Anyways, I looked at the schematic of the Hiland M644, and I notice the implemented (extended) hardware option. Could that be ported to an smaller MCU?
It's not like I'm testing xtals everyday, but anyways I know the workaround: to have k-firmware handy.
Pay attention to this simple modification, which was suggested earlier by Yuriy_K. I think it can be easily adapted to test quartz on both k-firmware and m-firmware. You only need 1 port for the frequency meter input. ;)
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4564999/#msg4564999 (https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4564999/#msg4564999)
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 12, 2024, 12:56:01 pm
Thanks, I've overlooked that post.

That more simple circuit seems easier to connect by the existing f-input port of a clone?, or as you say, we would have to allocate one pin for this?
Anyways, it looks the HCF4060B it's being used as a /16 frequency divider. I suppose that would have to be taking under consideration on the firmware or measurements.

I'm not familiar with that IC, so looking at the datasheets, I notice the manufacturers recommend to add an additional resistor to what Yuriy_K implemented. That series resistor is supposed to be "for power limitation and assuring a minimum transconductance". For further study, I refer an example (of the SMD equivalent) with some recommended values.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 12, 2024, 01:07:29 pm
That more simple circuit seems easier to connect by the existing f-input port of a clone?, or as you say, we would have to allocate one pin for this?
Connect wherever is most convenient for you! The main thing is to simply understand the principle of operation of this circuit.

I'm not familiar with that IC, so looking at the datasheets, I notice the manufacturers recommend to add an additional resistor to what Yuriy_K implemented.
Why do you need this if Yuriy_K has already done a lot of work and showed you that most quartz are perfectly detected and tested by this method and this schematic?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 12, 2024, 01:19:43 pm
Please don't get me wrong, I don't doubt it works without the resistor. I'm just suggesting what could be done for further improving it (perhaps enabling it to reach higher frequencies), and/or recommended as an official hardware frontend.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 12, 2024, 01:25:28 pm
Feliciano, this circuit can be assembled in a few hours if you want or maybe even faster on a breadboard. Check its work and then tell us about your experiments and improvements, I think that many people will be interested.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 12, 2024, 02:04:12 pm
If you build Yuriy_K's HCF4060B based frontend you can simply use the basic frequency counter option in the firmware and add a line to the source code to multiply the frequency by 16.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 12, 2024, 07:05:50 pm
Yeah, I was thinking on breadboard this, because it's simple. My local provider has old stock of the IC, so I'll buy one to start the process. The thing is I don't have an f-input CTester handy, so I was thinking to use a 5MHz oscilloscope instead.

I'll let you know maybe next week.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strateg58 on March 13, 2024, 04:57:28 am
It seems that Vcc and Gnd are reversed. From the README:
Code: [Select]
Pinout for control output via probes:
  Probe #1:  Vcc (5 V)
  Probe #2:  pulse output (with 680 Ohms resistor to limit current)
  Probe #3:  Ground
  T0:        counter input
I changed the connection on the recommendation of Madires. The result is the same. The scheme does not work. I changed the capacity of C2, changed the connected transformers. There are no fluctuations after C2. If no one responded, then no one is using this function.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 13, 2024, 08:58:20 am
That circuit is used by several ring tester projects. I've built exactly that circuit and it works fine for me. The only critical components are C2 and C3 (PP film caps). Have you double-checked your PCB? Have all components the correct value? Have you checked the signal at the counter output (checking at the DUT might load the signal too much)?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strateg58 on March 13, 2024, 11:44:11 am
OK Madires. Could you give me links to projects where this scheme is applied? Can you post a photo of how you check the pulse transformer? I would like to see your waveform on the Counter output at the same time. There's one more thing I can't figure out. If I connect your circuit to Probe 1,2,3. How will I test the rest of the components? The tester already sees the input resistance of the circuit as a connected resistor.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 13, 2024, 01:10:42 pm
Strateg58: please don't be rude. Remember madires and the other people do this for free for helping others. And they(we) normally design and test each proposal before proposing it.

To use the ring tester hardware option, you need to enable and later use the proper entry on the menu:
Code: [Select]
/*
 *  ring tester (LOPT/FBT tester)
 *  - uses T0 directly as counter input
 *  - uncomment to enable
 *  - select the pulse output: either dedicated pin or probes
 *  - see RINGTESTER_PORT in config-<MCU>.h for dedicated pin
 */

#define HW_RING_TESTER
//#define RING_TESTER_PIN                 /* dedicated pin */
#define RING_TESTER_PROBES              /* probes */
(Of course the add-on circuit had to be connected/disconnected according to the measurement intended).

Regarding the waveforms, I made a simulation with some approximate values. (If madires would like to share with me(us) the exact pulse-train parameters, I could further improve the sim), but regardless, I think the attached prove the point.

EDIT:
Updated sim, with "ring pulses" clearly visible.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 13, 2024, 01:14:06 pm
OK Madires. Could you give me links to projects where this scheme is applied? Can you post a photo of how you check the pulse transformer? I would like to see your waveform on the Counter output at the same time. There's one more thing I can't figure out. If I connect your circuit to Probe 1,2,3. How will I test the rest of the components? The tester already sees the input resistance of the circuit as a connected resistor.

Please see Dumidan's post on page 282 (based on Bob Parker's ring tester). There are two options to connect the ring tester. The first one is to use dedicated pins (RING_TESTER_PIN). And the second one is to use the standard probe pins (RING_TESTER_PROBES), i.e. the ring tester is connected temporarily to the probe pins and T0 as long as the ring tester function runs. After that you simply remove the ring tester, end the ring tester function and return to the normal probing.
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 13, 2024, 01:23:03 pm
Regarding the waveforms, I made a simulation with some approximate values. (If madires would like to share with me(us) the exact pulse-train parameters, I could improve the attached graph, but regardless, I think the attached prove the point).

The trigger pulse is 2ms.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 15, 2024, 05:09:49 pm
I propose a new version of the addition of the TTester circuit for measuring quartz and ceramic resonators in the range of 100 kHz - 20 MHz. The Chinese version HCF4060BE with a supply voltage of 6V and the use of an internal divider, allows you to measure quartz up to 20 MHz. Malaysian variant up to 16 MHz. I did not manage to lower the frequency for sentries (32768 Hz).
I was looking whether this frontend variant could further improved. However, according to the datasheets, and some experiments I conducted on breadboard, as Yuriy_K inferred it highly depends on the particular IC-vendor available/choosed.

I don't know the makers of what he tested, and what results obtained from 5V, but the originals National CD4060B and Philips HEF6040B I found on my local market can only reach a few MHz if powered by the 5V of our CTester. It could go faster if powered by 12V, though. Therefore we could implement a boost converter and a filter for that, but IMO that would overcomplicate the frontend design. Or maybe it could be powered by the 9V of some CTesters, if that's the case.

Anyways, I found a manufacturer-recommended design and values for 32MHz. Perhaps somebody with a faster IC could test it and let us know.

And for eye candy, I also attach a 4MHz/16 waveform from the Philips on a breadboard, with the recommended design I posted earlier.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 15, 2024, 07:33:38 pm
Or you could use the 74HC4060 version (https://www.onsemi.com/pdf/datasheet/mc74hc4060a-d.pdf) which can go to 28-30Mhz 4.5V or a bit more at 5V.

Anyways, I found a manufacturer-recommended design and values for 32MHz. Perhaps somebody with a faster IC could test it and let us know.
Hmmm... The image you linked (CD4060B Crystal Oscillator - 32MHz.png) is for 32Khz and not 32Mhz
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 15, 2024, 08:33:06 pm
Apologies, my old eyes. I removed the misleading picture while looking for an updated one.

And regarding the 74HC4060 you linked, it seems a better IC for the task. Still, I can't find it locally, so maybe somebody already has it and can implement/tune a test circuit for high frequencies. Design considerations I suggest: As this is intented for test gear, a wide bandwidth and low power is desired, to allow testing of as many xtals as possible, and not overdriving some of those.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strateg58 on March 16, 2024, 06:02:13 am
Strateg58: please don't be rude.   Alas. Feliciano. I had no intention of being rude. I am grateful to Madires for the work he does and helps everyone.Just reading the text that it works this way and that's one thing. And to see with your eyes how it works from a photo or video, it's better. Now for the essence of my questions. My LOPT board is working. What I did. I connected the +5v and GND power supply directly to the tester board. The In Pulse input was left connected to Probe 2. I returned the previously removed diode D1 to its place and the board started. Then I replaced the C2 capacitor with 0.027uf. Since with a 0.1 uf capacitor, the tester showed only 5 units, and with a 0.027 uf capacitor, the tester began to show 8 units.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Strateg58 on March 16, 2024, 06:03:59 am
An oscilloscope with a 0.027uf capacitor
Title: Re: $20 LCR ESR Transistor checker project
Post by: rogerdammit on March 17, 2024, 07:39:25 pm
I just flashed my BSIDE ESR02 Pro with 1.51m (+ the cap.c fix) and I can't get the unit to calibrate and get weird values on certain terminals.

First I'm getting a reported ~50uF between terminals 2-3 with nothing connected to the unit. Putting an actual capacitor on 2-3 gives a reasonable value (but not on 1-2 nor 1-3 -- though resistors work).

I figured it was a calibration issue, so after measuring a 2.2uF cap 4x times I went to the Adjustment menu but it failed here:

Code: [Select]
a6  c0 12 13 23
32 29 157

I'm guessing c0 for 2-3 is too large.

Any ideas?

My build config is here: https://github.com/roger-/bside-firmware/tree/main/modified
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 17, 2024, 08:26:44 pm
Yes, the limit is 100pF. Could you please run a self-test and post the values?
Title: Re: $20 LCR ESR Transistor checker project
Post by: rogerdammit on March 17, 2024, 08:43:44 pm
Yes, the limit is 100pF. Could you please run a self-test and post the values?

Is the Test menu supposed to give values at the end? Mine doesn't, but after running it Show Values gives:


Ri-: 20.4 R
Ri+: 23.1 R
C0: 43 pF
R0: 0.14 R
Vref: 1093 mV
Vcc: 5001mV
AComp: 0mV
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 17, 2024, 09:11:55 pm
No, the self-test simply runs each test five times. I'm interested in the values of T1, T2, T3, T5 and T6.
Title: Re: $20 LCR ESR Transistor checker project
Post by: rogerdammit on March 17, 2024, 09:31:25 pm
No, the self-test simply runs each test five times. I'm interested in the values of T1, T2, T3, T5 and T6.

Ah, got it. Here are the values I get:


T1: 1093 mV
T2: 13 18 23
T3: -44 -88 -49
T4: (none shown)
T5: 0 0 0
T6: 4995 4995 4996
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 17, 2024, 09:45:45 pm
I think 50uF is too much for nothing connected. Please double check the cap.c you're using for the make is dated around dec 2023.

You could also check with older m-firmware, or k-firmware, to confirm/discard whether there's a hardware issue (the easier to fix: white solder residues).
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 17, 2024, 09:58:32 pm
In the meantime I found something curious: it looks the second number and pin of the 1.51m results text are shiftted 1bit upward. Is this intentional, or something that requires checking?
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 18, 2024, 06:07:32 am
Ah, got it. Here are the values I get:
T2: 13 18 23
T3: -44 -88 -49
These results are poor, especially in the T3 test. The results in tests T2-T3 should be close to 0 and not differ from each other by more than 5 units. Check the values ​​of the measuring resistors 680 Ohm and 470 kOhm.
You can compare the results of your tests with similar tests of other participants on page 369.
You also need to remove all the conductors that you connected for the ICSP interface and repeat selftest!
Title: Re: $20 LCR ESR Transistor checker project
Post by: madires on March 18, 2024, 11:10:16 am
In the meantime I found something curious: it looks the second number and pin of the 1.51m results text are shiftted 1bit upward. Is this intentional, or something that requires checking?

No, could be some display glitch.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Yuriy_K on March 18, 2024, 12:47:30 pm
In the meantime I found something curious: it looks the second number and pin of the 1.51m results text are shiftted 1bit upward. Is this intentional, or something that requires checking?

No, could be some display glitch.

This is the principle of constructing a color pixel matrix. Blue is on top, Green is in the middle, Red is at the bottom. The Blue image is raised 1/3 of a pixel relative to the Green, and the Red is 2/3 lower than the Blue. It's almost a line down... Look at the photo.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 18, 2024, 01:11:26 pm
That would explain it, but in my case, the shift looks like exactly 1 pixel, and only happens on that particular screen.

Anyways I will flash another color set to check.
Title: Re: $20 LCR ESR Transistor checker project
Post by: indman on March 18, 2024, 01:19:51 pm
Feliciano Is this 1 pixel shift visible when you use your 8x16_alt_hf font?
Will there be the same effect if you use a different font?
Title: Re: $20 LCR ESR Transistor checker project
Post by: Feliciano on March 18, 2024, 01:37:38 pm
Seems Yuriy_k observation about the RGB construction is the answer, but in my display is more noticeable than others (specially with a relatively small font). You can notice "the ladder" on the color line when using a terminals sequence R-G-B with the original 8x16_hf font. (And in fact that also explains the ghosting on the purple of my previous images with my custom font).

Thanks, guys.
Title: Re: $20 LCR ESR Transistor checker project
Post by: Kim Christensen on March 19, 2024, 12:32:06 am
Yea, my TC1 screen definitely exhibits this same color shift as Feliciano's. I guess we can't really complain since the tester was less than $25 when I bought it.

On another note, I did change my firmware so that it upscales capacitance, resistance and zener readings. No more 9700nF capacitors and 6800mV zeners for me.  ;D

Title: Re: $20 LCR ESR Transistor checker project
Post by: hapless on March 19, 2024, 04:38:33 am
This height issue should go away if you rotate your display 90 degrees in firmware... I wonder if this means that the little screens were manufactured to be used as vertical ones.