$20 LCR ESR Transistor checker project

[indman]

MasGanBro,try to use an firmware which I have attached in archive.
What will be on the display? Check whether there is power + 5.0B on the 4-6(VCC) th pin of the ATMega328 processor. For check that the firmware works you can insert into the ZIF panel on contacts 1-3(1-2,2-3) any serviceable light-emitting diode - when pressing the Test button it has to blink.

[MasGanBro]

MasGanBro,try to use an firmware which I have attached in archive.
What will be on the display? Check whether there is power + 5.0B on the 4-6(VCC) th pin of the ATMega328 processor. For check that the firmware works you can insert into the ZIF panel on contacts 1-3(1-2,2-3) any serviceable light-emitting diode - when pressing the Test button it has to blink.

Code: [Select]

Microsoft Windows [Version 10.0.17134.165]
(c) 2018 Microsoft Corporation. All rights reserved.

C:\Users\hore>cd C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>FlashK.bat

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m
'avrdude' is not recognized as an internal or external command,
operable program or batch file.

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>FlashK.bat

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x00ff00
avrdude: Expected signature for ATmega328P is 1E 95 0F
         Double check chip, or use -F to override this check.

avrdude done.  Thank you.


C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>FlashK.bat

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0xff00ff
avrdude: Expected signature for ATmega328P is 1E 95 0F
         Double check chip, or use -F to override this check.

avrdude done.  Thank you.


C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>FlashK.bat

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>REM Writing Flash + EEPROM + Fuses (L=F7, H=D9, E=04)

C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>avrdude -c avrisp -p m328p -P COM4 -b 19200 -e -U flash:w:"TransistorTester.hex":a -U eeprom:w:"TransistorTester.eep":a \-U lfuse:w:0xF7:m \-U hfuse:w:0xD9:m \-U efuse:w:0x04:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: erasing chip
avrdude: reading input file "TransistorTester.hex"
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: writing flash (30064 bytes):

Writing | ################################################## | 100% 33.51s

avrdude: 30064 bytes of flash written
avrdude: verifying flash memory against TransistorTester.hex:
avrdude: load data flash data from input file TransistorTester.hex:
avrdude: input file TransistorTester.hex auto detected as Intel Hex
avrdude: input file TransistorTester.hex contains 30064 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 19.06s

avrdude: verifying ...
avrdude: 30064 bytes of flash verified
avrdude: reading input file "TransistorTester.eep"
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: writing eeprom (871 bytes):

Writing | ################################################## | 100% 42.78s

avrdude: 871 bytes of eeprom written
avrdude: verifying eeprom memory against TransistorTester.eep:
avrdude: load data eeprom data from input file TransistorTester.eep:
avrdude: input file TransistorTester.eep auto detected as Intel Hex
avrdude: input file TransistorTester.eep contains 871 bytes
avrdude: reading on-chip eeprom data:

Reading | ################################################## | 100% 3.48s

avrdude: verifying ...
avrdude: 871 bytes of eeprom verified

avrdude: safemode: Fuses OK (E:FC, H:D9, L:F7)

avrdude done.  Thank you.


C:\Users\hore\Downloads\Anto\LCR-T4NoStripGridRev798>

Whoa. She revive  v1.13k 
Big Thanks Mr Indman 
and honestly, still confused to use. And font too big 
Im more simple guy, put in socket and press button.
but i can learn new habits. Hehehe

Thank you Sir. Thank you
===add edit===
Im sorry, i think must hold/long press to measure, like first turn on.
turns out, still just click.

and for same component in sequence, said resistor
we can put in socket and that auto measure, remove, then put next item, auto measure
is that?

tester not wrong again about jfet and can measure small ceramic value. i like it!

but, this happen when test jfet

for me, its okay, still see pin in picture
Sorry, i dont know why became portrait 

for mosfet, 'normal'


End of morning news. 

[orientalsniper]

Hello all, I have the AY-AT Clone (red board).

I just finished building it and the zener diode is heating up! It's marked as 6V8C. Does anyone have any idea why that's happening?

[bitseeker]

First, check that it's installed in the correct direction. Measure the voltage across it. If it's around 0.6V (or even less), it's backwards or faulty.

[Willem52]

See also the attachment in: https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1673066/#msg1673066

[madires]

but, this happen when test jfet

for me, its okay, still see pin in picture

The two '?'s indicate that the FET's drain and source couldn't be detected, i.e. drain and source are likely to be symmetrical. The m-firmware displays an 'x' instead of the '?'.

[rddube]

Hello everyone,

I have a big question, as I'm about to check capacitors in circuit and there are quite a few on the patient board.

So my question is, which version (M or K) is better for in circuit ESR testing of capacitors?

Many thanks to all the masters!

[madires]

Don't ask me! I think the k-firmware's ESR measurement might be slightly more accurate.

[indman]

So my question is, which version (M or K) is better for in circuit ESR testing of capacitors?

Transistor tester can't fully take measurements in circuit!
Even at the C+ESR mode at the outputs  without loading of the device there are voltage impulses + 5B that inadmissibly there is a lot of!
 For measurements in circuit it is necessary to use more specialized devices.IMHO

[garthk]

I was going to copy progrock, here, but I've run into trouble with the parts ordering:

My current plan is to order one of these kits

Then, instead of using all the parts the kit comes with, replace some of them with the parts listed here.

(I tidied up the links; any errors are all mine.)

Here's the trouble: Mouser want $25 for shipping to Australia unless I rack up $60 of order, DigiKey seem to want batches of 500, four other suppliers have minimum order sizes of $50-$100, RS have decent 681Ω and 475kΩ resistors I think I can get away with but don't have stock of the 0.1% voltage reference but I can find that on eBay for $6…  it's a mess.

So, zooming out: will throwing another $20-$50 on parts be this worth the effort, or will that $16 kit from two years ago give me decent enough results?

[madires]

Transistor tester can't fully take measurements in circuit!
Even at the C+ESR mode at the outputs  without loading of the device there are voltage impulses + 5B that inadmissibly there is a lot of!
 For measurements in circuit it is necessary to use more specialized devices.IMHO

I agree, a dedicated meter for in-circuit ESR would be the best choice.

[madires]

So, zooming out: will throwing another $20-$50 on parts be this worth the effort, or will that $16 kit from two years ago give me decent enough results?

No, that would be insane! If you get the parts for a few bucks when ordering other stuff anyway then do it.

[Willem52]

When people exactly know what to order, search for it on AliExpress too.
I order a lot there for years, because it is cheap (even with shipping cost, if applicable).

[+Mikie]

I was going to copy progrock, here, but I've run into trouble with the parts ordering:

Then, instead of using all the parts the kit comes with, replace some of them with the parts listed here.

(I tidied up the links; any errors are all mine.)

Here's the trouble: Mouser want $25 for shipping to Australia unless I rack up $60 of order, DigiKey seem to want batches of 500, four other suppliers have minimum order sizes of $50-$100, RS have decent 681Ω and 475kΩ resistors I think I can get away with but don't have stock of the 0.1% voltage reference but I can find that on eBay for $6…  it's a mess.
[/quote]

I've just returned from picking up my order at Farnell. For $25 I got multiple of all the parts for this, plus some extra pots and MOSFETs for my power supplies repair. Digikey wanted 20 bucks for a delivery to Oz, I didn't bother checking at Mouser since Farnell had everything (kinda) except the resistors. I'm saying "kinda" cause I'm noticing a lot of parts are now "available in 6-7 days", meaning they are actually not in Australia. Anyway, not in a hurry, so I ordered them 2 weeks ago.

Similarly to you, I couldn't find a suitable 0.1% resistors there or anywhere else in Australia. I figured having a 681 ohm in high precision is a waste of money, since the value is off from the word go. So I ordered 30 of each resistors in plain 1% and I'll pick the matched triplets out of the pile. I'm not THAT interested in precision anyway. Main thing to me is identifying what the part is and if it is actually functioning, values.... not so much.

I'm now looking forward to firing this thing up and seeing what it does.

P.S. I also got 3 mini test clips and a bit of wire from Jaycar to be able to test components in-circuit. Again, important thing is to find out whether something is blown to avoid removing it unnecessarily and risking the board in the process. I'll 3D print the box for it, which seems to have occured to many others since there are already multiple designs available on Thingiverse.

[+Mikie]

I've tried compiling the 1.33m firmware with WinAVR, and I got an error in a file I haven't touched. Any ideas?

ST7735.c: In function 'LCD_CharPos':
ST7735.c:341: error: expected expression before ';' token
ST7735.c: In function 'LCD_ClearLine':
ST7735.c:417: error: expected expression before ')' token
ST7735.c:419: error: expected expression before ')' token
ST7735.c:421: error: expected expression before ')' token
make.exe: *** [ST7735.o] Error 1

> Process Exit Code: 2
> Time Taken: 00:07

Edit: Never mind, I figured it out. In file "Config_328.h" one of the LCD display definitions is already uncommented. I uncommented the correct one as per file "clones", which made the compiler spit the dummy, cause 2 displays at once. Makes sense Result:

AVR Memory Usage
----------------
Device: atmega328

Program:   32392 bytes (98.9% Full)
(.text + .data + .bootloader)
Data:        241 bytes (11.8% Full)
(.data + .bss + .noinit)
EEPROM:      852 bytes (83.2% Full)
(.eeprom)

[BradC]

Similarly to you, I couldn't find a suitable 0.1% resistors there or anywhere else in Australia. I figured having a 681 ohm in high precision is a waste of money, since the value is off from the word go.

I went 681 & 475k 0.1% (from Digikey) and just changed the constants in the source to tweak it up. I thought as long as the matches between channels were close the absolute value wasn't so important.

[Azure]

P.S. I also got 3 mini test clips and a bit of wire from Jaycar to be able to test components in-circuit. Again, important thing is to find out whether something is blown to avoid removing it unnecessarily and risking the board in the process.

You cannot reliably test components in circuit with this tester.  An in circuit tester uses a different method to be able to test components in circuit.

As long as there is no residual charge in any of the components you shouldn't damage the tester, you will just get incorrect readings.  Components will appear to be something they are not, have incorrect values or appear shorted depending on the other components around the part you are testing.

[madires]

Regarding the 0.1% resistors, inside the EU you can them in single quantities for €0.29-0.35 (Yageo TH) or €0.25 (Panasonic SMD) from reichelt.de.

[+Mikie]

You cannot reliably test components in circuit with this tester.  An in circuit tester uses a different method to be able to test components in circuit.

As long as there is no residual charge in any of the components you shouldn't damage the tester, you will just get incorrect readings.  Components will appear to be something they are not, have incorrect values or appear shorted depending on the other components around the part you are testing.

I realize that, I'm just hoping for go/no-go for components to speed up the diagnosis of faulty circuits. So you're saying even that wouldn't work?

Regarding the 0.1% resistors, inside the EU you can them in single quantities for €0.29-0.35 (Yageo TH) or €0.25 (Panasonic SMD) from reichelt.de.

I didn't look any more into the precision resistors, as what was available here in Australia were not specified values. 681 ohms and 475k weren't exactly what was specified. While playing with WinAVR I've realized that these values can be specified in software what they actually are, and that I could have used different values and declared them in software accordingly. I haven't seen that bit of info mentioned anywhere in this thread, and it would have been useful in the "replacement parts ordering" phase Maybe something to add to the documentation?

Again, utmost measurement accuracy isn't that important to me, but it may be to others.

[bitseeker]

You cannot reliably test components in circuit with this tester.  An in circuit tester uses a different method to be able to test components in circuit.

As long as there is no residual charge in any of the components you shouldn't damage the tester, you will just get incorrect readings.  Components will appear to be something they are not, have incorrect values or appear shorted depending on the other components around the part you are testing.

I realize that, I'm just hoping for go/no-go for components to speed up the diagnosis of faulty circuits. So you're saying even that wouldn't work?

It depends how badly you misinterpret the circuit layout. Take for example a go/no-go on some filter caps. You measure one, in circuit, and the capacitance seems to match the rating on the side and the ESR looks low. So, that might look like it's an OK cap. However, there are several in parallel on the board, which means the capacitance is less than it should be and the ESR is higher than it appears.

That's a simple example that usually isn't hard to detect by examining the PCB traces. But not every case is necessarily like that, especially if the junction of active components turn on during the measurement. So, if you know how the circuit works, you may be able to make some interpretations. If not, then what you see may not be what you get.

[MasGanBro]

The two '?'s indicate that the FET's drain and source couldn't be detected, i.e. drain and source are likely to be symmetrical. The m-firmware displays an 'x' instead of the '?'.

Ah, thanks for info. I thought that a fake J201.

Again (peace for ask too much), some question
- the batt is around 8.7x V, but in lcr-t4 always show around 7.0x V
really too much drop. That normal?

- if ditch battery, use 9-12V adaptor, what polarity? Center negative or positive?

- what the latest tester can handle all feature/function?

Thanks

[+Mikie]

I'm not sure about battery voltage thing, it could be a setting in firmware or hardware problem/wrong component. Look at the circuit and check components along the power supply lines.

For external power jack - center=positive (standard)

From what I understand, the best Chinese clone is the one marked "AY-AT" on the board. That's what I actually bought, except when it arrived, there were no such markings on the board. It does look the same, and it worked straight up after I soldered everything. So a copy of a copy, but so far seems ok.

I'm planing to use 1.33m or trendy-1.26m firmware. Not sure what's the difference (maybe Marcus will tell us). From what I worked out, you can choose features you want when you are compiling your own firmware, within reason and within the constraints of memory size.

[madires]

Again (peace for ask too much), some question
- the batt is around 8.7x V, but in lcr-t4 always show around 7.0x V
really too much drop. That normal?

Maybe the resistors of the voltage divider for battery monitoring have different values. Check the voltage drop across the BJT switching the power. Is there a diode for reverse polarity protection? You can adjust all values in the firmware's configuration file.

- what the latest tester can handle all feature/function?

DIY There's no clone with all hardware options on board.

[madires]

I'm planing to use 1.33m or trendy-1.26m firmware. Not sure what's the difference (maybe Marcus will tell us). From what I worked out, you can choose features you want when you are compiling your own firmware, within reason and within the constraints of memory size.

For a while there were two branches of the m-firmware, one for the classic HD44780 text display (classic) and another one for graphic displays (trendy). This was necessary to support the ATmega 168 with just 16kB flash. After dropping the support for the 168 the two branches were joined together. So the latest and greatest version is 1.33m.

[rddube]

For any of  you thinking you can test capacitors in circuit, the answer is yes and no.

Check out this video where the person explains it quite well: