$20 LCR ESR Transistor checker project

[stj]

ah right,
i thought it was for the "small parallel cap" for inductance testing.
but couldnt see a film cap.

[hapless]

That's an interesting idea. But how would it be controlled? Some of the controller's pins are already pulling double duty...

[stj]

i spoke by email about this with mr Heinz a while back, he thought re-using the pin that is connected to the voltage reference was one way, if i remember right.

i already have a fet driven relay mod on mine, but i switch the fet manually at the moment.
btw, if you put a relay near the socket you should use a metal-screened "telecom" type or it may effect the inductor with it's field.

[madires]

The optional relay for discharging caps is driven by PC4 (ATmega 328), which is also the input for the optional external 2.5V reference. k and m-firmware support this (m: HW_DISCHARGE_RELAY in config.h). You'll find the old circuit plus an improved one in Karl-Heinz's documentation (section 2.2.1).

[stj]

we arent talking about the relay for discharge,
we are talking about the parallel cap for small inductor testing.

i doubt the relay would be much good against a fully charged low impedence cap anyway - it would probably have it's contacts burned.

[madires]

Ok, so the idea is to use PC4 (ATmega328) to drive a relay for a parallel cap instead of the discharging relay. At the moment the driver function for the discharging relay is integrated in the k-firmware (no switchable option). That would need to become an option while adding another one for the parallel cap. The 324/664/1284 dev board has a relay plus cap already on board (driven by PC2).

PS: I'm no friend of the discharging relay also.

[pepe10000]

Thanks to the forum I already have the rotary encoder installed and running on one of my LCR-T4.

I have made some photos in case someone is interested in making the modification that can serve as a guide.

Also included are photos of the 9V battery charger with constant current made with an LM317 and a still unfinished sub-coupler to measure optocouplers.

In order to operate in the correct direction the rotary encoder with the soldered cables in this way the following lines must be changed in the "config_328.h":

#define ENCODER_A        PD3
#define ENCODER_B        PD1

A greeting.

[deriterkeeg]

Something tells me that whoever posted that doesn't really know what it means. Correct me if I'm wrong, but I'd say it's either 1602 or 12864, not both. The picture is probably (probably!) a better indication of what's actually for sale.

Ok, buy it and tell us about your experience.
This kind of description is common. Who knows about the subject asks a question, others fall into the trap!
cheaper isn't the best.
regards

[madires]

While checking my to-do list I've stumbled across CLDs/CRDs (current limiting diodes / current regulater diodes). A quick search shows that they are availiable up to about 5mA (high current ones up to 23mA), which can be handled by the transistor tester. Common types seem to be 1N5285 up to 1N5314. If you got some CLDs and like to support this project, I'd appreciate a few samples

The next version of the m-firmware will be named just "Component Tester" without any hint about the edition to make things less complicated. So far I've added R_DS and Vf (body diode) for MOSFETs, and support for fixed IR receiver modules. Also I've moved the component symbol from the bottom to the right to have more lines for data (data on the left, symbol on the right).

[texaspyro]

While checking my to-do list I've stumbled across CLDs/CRDs (current limiting diodes / current regulater diodes).

Don't forget my favorite...  the tunnel diode    I actually use the beasties (plus very common in old Tek scopes).   They have the interesting property of exhibiting negative resistance above their current threshold point.   I don't think anybody makes them anymore.   I have to buy them from Russia. 

I think I have a local source of some CRDs.  I'll check today.

[hapless]

Something tells me that whoever posted that doesn't really know what it means. Correct me if I'm wrong, but I'd say it's either 1602 or 12864, not both. The picture is probably (probably!) a better indication of what's actually for sale.

Ok, buy it and tell us about your experience.
This kind of description is common. Who knows about the subject asks a question, others fall into the trap!
cheaper isn't the best.
regards

Looks like you took it the wrong way. I was referring to the person who posted the listing. That description is not just common, it looks like a "standard" copy/pasted one that's used all over the place. Useless. The images are supposedly the only clue of what you're buying. If you think that that particular seller is selling something else, that's even worse.

While checking my to-do list I've stumbled across CLDs/CRDs (current limiting diodes / current regulater diodes). A quick search shows that they are availiable up to about 5mA (high current ones up to 23mA), which can be handled by the transistor tester. Common types seem to be 1N5285 up to 1N5314. If you got some CLDs and like to support this project, I'd appreciate a few samples

The next version of the m-firmware will be named just "Component Tester" without any hint about the edition to make things less complicated. So far I've added R_DS and Vf (body diode) for MOSFETs, and support for fixed IR receiver modules. Also I've moved the component symbol from the bottom to the right to have more lines for data (data on the left, symbol on the right).

Wouldn't those diodes mess up at least some of the measurements if permanently installed? Is it even possible to compensate for a semiconductor at the input of a semiconductor tester?

As an aside, would it be a lot of work to print out everything after an underscore a couple of pixels lower than the rest and then to reset position at the null byte? I haven't looked at the code in a long time...

[madires]

Wouldn't those diodes mess up at least some of the measurements if permanently installed? Is it even possible to compensate for a semiconductor at the input of a semiconductor tester?

The CLDs won't be installed, they are going to be checked

As an aside, would it be a lot of work to print out everything after an underscore a couple of pixels lower than the rest and then to reset position at the null byte? I haven't looked at the code in a long time...

Yes. Either we would have to add a low-height font to support displays with a fixed page size, or we would need a screen buffer for displays without a read function.

[texaspyro]

While checking my to-do list I've stumbled across CLDs/CRDs (current limiting diodes / current regulater diodes).

I think I have a local source of some CRDs.  I'll check today.

I bought some 330 uA and 390 uA CRD's today.   K firmware does not see them.   1.26M firmware says they are diodes with If = 308 and 389 uA.   What does the number in (..) after the Vf mean?

I suspect the way to test for CRDs is to try driving them with different voltages and if the current stays (reasonably) constant that they are CRD's.

Madires, if you want to try them, PM me your address and I'll send them out.

[deriterkeeg]

Looks like you took it the wrong way. I was referring to the person who posted the listing. That description is not just common, it looks like a "standard" copy/pasted one that's used all over the place. Useless. The images are supposedly the only clue of what you're buying. If you think that that particular seller is selling something else, that's even worse.

Apologies, I misled the sense of your former reply.
Being an intensive eBayer, as soon as a picture doesn't fit the description, I suspect the listing! 
I never bought on aliexpress yet. Considering good bargains, is it equivalent to eBay ?
Regards

[madires]

I bought some 330 uA and 390 uA CRD's today.   K firmware does not see them.   1.26M firmware says they are diodes with If = 308 and 389 uA.   What does the number in (..) after the Vf mean?

The number in parentheses is Vf for the low current measurement (470k resistor, around 10µA). It's only displayed when the voltage is below 250mV, which mostly happens for Ge or Schottky diodes.

[pepe10000]

Hello, I installed the EC11 rotary encoder (20 steps 20 pulses according to distributor) in two units of the LCR-T4 those yellow color (Chinese clones) and with the firmware m everything works perfect, right, left, slow spin, normal spin, Quick spin etc.

But with the k firmware, it works fine but only with slow turns, if you turn the encoder at half speed or fast the screen fails, text lines jump, vertical streaks go out or it goes blank even though the tester keeps running.

Example:



I have compiled the latest version available (Trunk 699) with the options:

CFLAGS += -DWITH_ROTARY_SWITCH=2
CFLAGS += -DCHANGE_ROTARY_DIRECTION

I have also put the Pull-UP resistances recommended in the manual and quartz crystal at 16MHZ (photos in post # 3006 a little higher).

It happens to me in the two units exactly the same, is that normal?

[madires]

That's strange! I've forwarded your report to Karl-Heinz.

[ja421]

do you really mean this:

Code: [Select]

CFLAGS += -DWITH_ROTARY_SWITCH=2( "=2" )?

[pepe10000]

do you really mean this:

Code: [Select]

CFLAGS += -DWITH_ROTARY_SWITCH=2( "=2" )?

Yes, =2, according to the make:

# If your encoder has the same count of pulses at any switch as indexed positions (detent) for every turn,
# you should set the WITH_ROTARY_SWITCH to 2 or 3.

I tested with 2 and with 3, and the result is the same, the LCD fails if the encoder is rotated to medium or fast speed.

A greeting.

[kubi48]

The rotary encoder extension can only work correctly with the default pin setting, if the communication ports for the display are swiched to low (0V) and high level (5V). Because this board use a display controller, which don't tolerate 5V signals, the ATmega outputs are swiched to 0V only (Makefile option LCD_SPI_OPEN_COL). The high level is generated with pull-up resistors. I see only one workaround to use other port signals for the rotary encoder, which are not used for the display controller communication. Probably the PD5 signal is not used, but PD4 is used as LCD-Reset. The LCD-Reset signal is rised to high level at the program start. Probably this signal can also be generated with a RC combination. So you can use PD4 and PD5 for the rotary encoder.
Of course you must set the Makefile options ROTARY_1_PIN and ROTARY_2_PIN to change the software.
If you remove the Makefile option LCD_SPI_OPEN_COL, the rotary encoder will probably work correctly, but the supply voltage of the LCD controller can increase to a illegal value.

[pepe10000]

The rotary encoder extension can only work correctly with the default pin setting, if the communication ports for the display are swiched to low (0V) and high level (5V). Because this board use a display controller, which don't tolerate 5V signals, the ATmega outputs are swiched to 0V only (Makefile option LCD_SPI_OPEN_COL). The high level is generated with pull-up resistors. I see only one workaround to use other port signals for the rotary encoder, which are not used for the display controller communication. Probably the PD5 signal is not used, but PD4 is used as LCD-Reset. The LCD-Reset signal is rised to high level at the program start. Probably this signal can also be generated with a RC combination. So you can use PD4 and PD5 for the rotary encoder.
Of course you must set the Makefile options ROTARY_1_PIN and ROTARY_2_PIN to change the software.
If you remove the Makefile option LCD_SPI_OPEN_COL, the rotary encoder will probably work correctly, but the supply voltage of the LCD controller can increase to a illegal value.

I have the power supply of the LCD controlled by an AMS1117 3.3, so I think it would not be a big problem.

The strange thing is that with firmware m works perfectly.

If you wish tomorrow I can do the test to remove the LCD_SPI_OPEN_COL to see what happens.

Thanks and best regards.

[upsss]

Hello, I installed the EC11 rotary encoder (20 steps 20 pulses according to distributor) in two units of the LCR-T4 those yellow color (Chinese clones) and with the firmware m everything works perfect, right, left, slow spin, normal spin, Quick spin etc.

But with the k firmware, it works fine but only with slow turns, if you turn the encoder at half speed or fast the screen fails, text lines jump, vertical streaks go out or it goes blank even though the tester keeps running.

Example:



I have compiled the latest version available (Trunk 699) with the options:

CFLAGS += -DWITH_ROTARY_SWITCH=2
CFLAGS += -DCHANGE_ROTARY_DIRECTION

I have also put the Pull-UP resistances recommended in the manual and quartz crystal at 16MHZ (photos in post # 3006 a little higher).

It happens to me in the two units exactly the same, is that normal?

Unfortunately it is "normal" with this particular tester.  I have exactly the same problem and I am also using exactly the same LCR-T4 version tester.  I reported this problem back in April on Page 78 staring with post 1926, a lot of advice but no solution.  After recently changing my crystal to 16MHz it looks like it is behaving a little better but still if I rotate the encoder anyway faster than about 1 click per second the display will get scrambled or most of the time the display will become blank and the only way to recover is to the reset the processor.  I gave up trying fixing it so I installed a reset switch so I can reset the darn thing without opening my box every time it happens.

On post 2997 you can see a picture of my tester.  This picture is before I installed the reset switch.

[pepe10000]

I have compiled the latest available version k (702) with the option:

#CFLAGS + = -DLCD_SPI_OPEN_COL

And everything works perfect, so far nothing has broken and measurements go well.
The rotary encoder can be rotated at any speed without affecting the screen.

In these days I will be attentive to the operation in case something strange happens to report it.

Many thanks to all for the help and greetings

[Pukker]

Hi everybody,

Does someone have the latest K and M versions for AY-AT tester.
Don't have knowledge of compiling etc.
ehh, shame, and to lazy to learn,
maybe when I have lots of time.

Thanks anyway.
Pukker

[stj]

K here: