$20 LCR ESR Transistor checker project

[madires]

The BSide ESR02 has an ST7565 compatible display. If the display output is shifted you can change LCD_ST7565_H_OFFSET in the Makefile (from 4 to 0) and recompile the firmware. In case you like to try the m-firmware please see https://github.com/roger-/bside-firmware for a compiled m-firmware.

[Yuriy_K]

I burned mega328_st7565 to the tester, and that is the only one which is kinda working except that the screen size doesn't fit

I really don't know what to do with the makefile or how to use it, looks like a compiling thing

Did some tests still the same problem with those uF's

Your problem is that you need to have some knowledge of programming and understand how to configure some parameters in the makefile.
Here I fixed the horizontal offset of the text displayed on the display...

Now about the value of large capacities. In the firmware you can adjust this value, but you must take into account that the readings measured at a constant current differ from the readings at a frequency of 100 Hz. At 100 Hz the readings are noticeably lower...

[Davo013]

Wow Thnx 
Why is the battery voltage doubled? i
You are totally right, it's the lack of  knowledge...

I know electronics but, programming is a whole other department
It took so many time only to get where i'm now, and programming etc, i don't have the time for that, electronics is what i like.
I find this stuff quite interesting, i like to repair stuff, to much stuff is thrown in the garbage trunk.
A while ago i found this topic, and i thought okay, let's give it a try though...
It really took me a-lot of energy to repair the bside & burn the firmware
I Don't have linux, and if i have to setup a linux system & learning all of the other stuff is giving me to much stress to keep everything going over here
sometimes it's better to throw things away and give up, and buy another one...
Life lol

Iám aware about the freq at 100/120 hz but hasn't that more effect on the esr as for the capacity

[Davo013]

The higher battery voltage was already in the firmware i just saw it in my other pictures....

[madires]

The OSHW firmwares can be also compiled on MacOS and Windows.

[Davo013]

So with command prompt in windows you open avrdude.exe, and with the makeme file + .hex & .eep you have to upload it somehow into the 328 or just in windows memory and then compile it.
all those code's in avrdude not as easy as it looks... doing it the right way..
isn't there some decent tutorial or so?

maybe we have to a  little bit longer for a.i haha

[madires]

There's a ton of tutorials and videos. Please search for 'AVR toolchain for windows'.

[Yuriy_K]

Why is the battery voltage doubled? i
You are totally right, it's the lack of  knowledge...

Iám aware about the freq at 100/120 hz but hasn't that more effect on the esr as for the capacity

I have corrected the settings for the battery and some parameters for the example. You can compare it with the previous firmware.
I use the WinAVR environment to compile the firmware.

[Davo013]

I found comparator and i can see what you changed next nice work!

I have winavr installed & ii’m trying to figure out how to run everything

[Davo013]

This is going to take to much time & frustration to learn...
I haven't got that much experience in this kinda stuff
Butt I really appreciate your help bro! & Madires also! 
Maybe it's simple? I don't know... watching all those vids  made it look more harder for me

[Davo013]

There's something wrong & i doný know what is causing it...

When i attach a small capacitor 22 or 47uF and click on the button, Testing... and after the 3rd point the power goes off??
this is with a 4700uF also, when i use 3300uF it works okay: testing....... and then the capacitor test
Really weird... the battery is 8.3v so that's enough, i never had those problems even at 7v it worked.
It looks like it's crashing or so

Well i did some testing and with a 9.3v battery and the meter didn't crash with values between 330uF & 3300uF that is quite odd
And values from 1uF/8,2uF didn't make it crash also, if it take a cap between 10uF and 330uF it crashes
I tried a few other firmwares and the problem stays the same WTF is going wrong??

[Kim Christensen]

Well i did some testing and with a 9.3v battery and the meter didn't crash with values between 330uF & 3300uF that is quite odd

Maybe it's a combination of regulator voltage dropout spec and a battery with higher than normal ESR? Perhaps when testing larger capacitors, the unit draws a bit more current...
What voltage regulator does your tester use?

[Davo013]

This one

[Davo013]

it's a kinda strange that 1uF/8,2uF it works,
from 10uF/220uF it crashes,
from 330uF.3300uF it work
From 4700uF it crashes 
tried different voltages etc

but when it's on with a cap from 470uf and i replace it with a 220uf it works
you could have a point there with esr while booting the regulator is 5v 30mA

There.s another 3.5v but that one for the display

i used my thermal cam also and nothing remarkable to see,,,

[Kim Christensen]

You could use a scope on the 5V rail to see if the voltage dips when the unit crashes. Interesting that they used the HT7150-1 with it's 30mA spec vs the MCP1702 which is good for 250mA. You could also measure the current draw to see if it's close to the limit. Just a guess.

[Yuriy_K]

it's a kinda strange that 1uF/8,2uF it works,
from 10uF/220uF it crashes,
from 330uF.3300uF it work
From 4700uF it crashes 
tried different voltages etc

Can you show the display readings of the Show data menu item after Selftest?

When examining your circuit, I noticed a significant difference in U4. What is the voltage between GND and GND0?

When performing Selftest, it is necessary to disconnect all measuring wires, except for the short jumper shown in the photo below. In the k-firmware, a series of short pulses is used when measuring the ESR, and long wires can affect the measurements and readings of the ESR. As I showed on my homemade T-tester.

[madires]

Looks like a hardware issue. Have you swapped C10 and C12 by any chance?

[indman]

Looks like a hardware issue.

I drew the schematic diagram of this clone because I have this device and have studied all its features well.
In red color I showed the improvements that are very necessary to make so that the device works stably!!!
It is especially important to replace the weak and low-quality stabilizer HT7150 with a stronger MCP1702!!!
C10 can be removed from the circuit altogether, its absence will not affect the operation of the circuit, but C12 is important and preferably of high quality!!!
Yuriy_K made a correct comment on the calibration procedure. Initially, you need to disconnect all long conductors and calibrate with a short jumper and then check the details on the same contacts. If longer conductors are needed, then the calibration procedure must be repeated and the parts checked only on these contacts.
It is also very important to correctly complete all calibration steps and use high-quality calibration capacitors, because the correct operation of the device depends on this. All these nuances are discussed in detail in the author's manual, read very carefully, otherwise you will constantly have questions and problems.

[Per Hansson]

Davo013: I think you have reversed the position of C10 and C12, compare this picture of mine, it is important that the AREF capacitor is of the correct type

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1371182/#msg1371182

[indman]

  it is important that the AREF capacitor is of the correct type

As I wrote above, all the latest k-firmware and m-firmware work perfectly without this capacitor C10 at the AREF pin!

[Davo013]

You could use a scope on the 5V rail to see if the voltage dips when the unit crashes. Interesting that they used the HT7150-1 with it's 30mA spec vs the MCP1702 which is good for 250mA. You could also measure the current draw to see if it's close to the limit. Just a guess.

Nah i'm just going to order some other parts this versions sucks haha

it's a kinda strange that 1uF/8,2uF it works,
from 10uF/220uF it crashes,
from 330uF.3300uF it work
From 4700uF it crashes 
tried different voltages etc

Can you show the display readings of the Show data menu item after Selftest?

When examining your circuit, I noticed a significant difference in U4. What is the voltage between GND and GND0?

When performing Selftest, it is necessary to disconnect all measuring wires, except for the short jumper shown in the photo below. In the k-firmware, a series of short pulses is used when measuring the ESR, and long wires can affect the measurements and readings of the ESR. As I showed on my homemade T-tester.

I'm aware of the inductance of the alligator clips, i made screens from the show data & made screens from the calibration also

Looks like a hardware issue. Have you swapped C10 and C12 by any chance?

Good one!, but no, i took them both of the board and measured them when I noticed that they where shifted..

Looks like a hardware issue.

I drew the schematic diagram of this clone because I have this device and have studied all its features well.
In red color I showed the improvements that are very necessary to make so that the device works stably!!!
It is especially important to replace the weak and low-quality stabilizer HT7150 with a stronger MCP1702!!!
C10 can be removed from the circuit altogether, its absence will not affect the operation of the circuit, but C12 is important and preferably of high quality!!!
Yuriy_K made a correct comment on the calibration procedure. Initially, you need to disconnect all long conductors and calibrate with a short jumper and then check the details on the same contacts. If longer conductors are needed, then the calibration procedure must be repeated and the parts checked only on these contacts.
It is also very important to correctly complete all calibration steps and use high-quality calibration capacitors, because the correct operation of the device depends on this. All these nuances are discussed in detail in the author's manual, read very carefully, otherwise you will constantly have questions and problems.

You made the schematic!
Ah Cool Nice work! 
I'm going to order those regulators, are those the right ones?
MCP1702T-5002E
LM4040AIM3X-5.0

Weird that the regulaor doesn't has a regulator cap... just an 10uF elco can make a difference in stabilty
 The manual what you are talking about, is that ttester.pdf?

Davo013: I think you have reversed the position of C10 and C12, compare this picture of mine, it is important that the AREF capacitor is of the correct type

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1371182/#msg1371182

It's the same one, the other cap 1nF has a bigger package size 0805
Which class has it to be? i have some over here but i really don't know which class they are..
Maybe test 'm with a heat source for stability? those frikkin things never have markings...

  it is important that the AREF capacitor is of the correct type

As I wrote above, all the latest k-firmware and m-firmware work perfectly without this capacitor C10 at the AREF pin!

So ditch C10 lol

[indman]

I'm going to order those regulators, are those the right ones?
MCP1702T-5002E
LM4040AIM3X-5.0
Weird that the regulaor doesn't has a regulator cap... just an 10uF elco can make a difference in stabilty
The manual what you are talking about, is that ttester.pdf?

Yes, if you find an original and high-quality MCP1702T-5002E, then you can refuse the external LM4040AIM3X-5.0, it is not needed just like the C10
The manual for k-firmware is ttester.pdf, you wrote it correctly.

[Davo013]

I'm going to order those regulators, are those the right ones?
MCP1702T-5002E
LM4040AIM3X-5.0
Weird that the regulaor doesn't has a regulator cap... just an 10uF elco can make a difference in stabilty
The manual what you are talking about, is that ttester.pdf?

Yes, if you find an original and high-quality MCP1702T-5002E, then you can refuse the external LM4040AIM3X-5.0, it is not needed just like the C10
The manual for k-firmware is ttester.pdf, you wrote it correctly.

Lol

[indman]

Davo013, I looked at your photos from the ShowData archive. Your clone now has Atmega installed, which is of Chinese origin and is not of the highest quality. This can be clearly seen from the internal resistance of the measuring ports. Even if you replace the +5V stabilizer, problems with capacitance measurement may remain with a 50% probability. Therefore, read my recommendations, which I outlined in detail in this post, especially points 4 and 5
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg5552775/#msg5552775

[Phil1977]

It´s the same issue I mentioned in this thread 2 pages ago, with a different type of tester.

I have a 1000uF cap between terminal 1 and 3. I switch the tester on, it says "Bat12V ok, testing..." and a few seconds later it switches off.

I attached the scope to the 7550 voltage regulator. The yellow line is the 12V-intermediate voltage in my tester (Battery level), the cyan line is the output of the 7550. I would really like to exchange the IC for something better, but the scope is quite convinced that that´s not the problem:




The first page of the "Show Data" screen is:

Version: 1.12k
R0=0.18 0.17 0.17Ohm
Ri_high=15.9Ohm
Ri_low=13.1Ohm

Any other ideas? I think about adding programming pins to the device, reprogram the AVR, (re-)set the fuses and as last resort exchanging the AVR against an original one.