$20 LCR ESR Transistor checker project

[indman]

Just a short observation though. On the schematic it is missing the LED between R6 and Q3.

Yes, thank you, I will supplement the scheme with this missing element, which plays an important role in the scheme.

I am confronting myself with the following problem: while the tester is working fine, when I press the TEST button, the current consumption is 220 mA (!!) and the battery voltage is reported wrong (7.72V instead of 8.9V). Transistor Q1 gets very hot. Alcohol evaporates almost instantly on it, in comparison with the other components. If I supply 6V instead of 9V, the current consumption drops to about 70mA, still too much IMO. Could it be a faulty capacitor C1?

This is already a known unpleasant problem for this clone. Look carefully at the picture I attached below and everything will become clear to you. Instead of a 3.3V Zener, a 3.3 volt stabilizer should be installed in the sot-23 to power the TFT screen, and the board is divorced incorrectly.2 and 3 outputs shorts are connected on the board. Drawn in red. Tracks need to be cut. In fact, there is a zener diode directly parallel to the output of the 7805. VCC instead of five sinks to 4 volts, and wild consumption from the battery. In the absence of stabilizers in sot-23, I put 1117-3.3 in sot-223, it is better to leave the resistor in front of the TFT screen at one 100 ohms, but you only need to solder it from the seat, it goes straight to 5 volts.

[masster]

@indman
1) Is the schematic attached the correct one? I mean, having all the corrections already applied?
2) Resistors R3 and R5 are 33K. Shouldn't be R3=10K and R5=3K3 to show the correct value of the battery voltage?
3) I have attached a high resolution photo of my board. Can you draw on it again, please? Because the other photo is low resolution, and I can't see exactly what to cut and what to connect.

[indman]

1. Yes, the scheme is correct.
2. You can change the resistors R3-R5 if you want to use new k and m-firmware. Or compile the firmware for the divider 33k/33k yourself.
3. I showed in the photo which jumper should be removed.

[free_electron]

has anyone ported this to a 329 or 629 ? how much code would need to change ?

[madires]

I'm not aware of anyone. No idea! If the 329 is basically a 328 plus additional features, then it should be just some minor adaptions.

[Feliciano]

Appart from being on a 64pin case, the main features of the 329pa look similar to those of 328pb. Attached a quick comparison.

[Jacon]

... a 328 plus additional features...

329 seems to have additional LCD controller only...

[masster]

Quote from: indman on August 21, 2022, 06:18:05 am

1. Yes, the scheme is correct.
2. You can change the resistors R3-R5 if you want to use new k and m-firmware. Or compile the firmware for the divider 33k/33k yourself.
3. I showed in the photo which jumper should be removed.

>@indman

It would help a lot for future owners of Fish-8840TFT to find in Clone Tester folder on YandDisk a detailed description of the modifications they have to make. In my opinion, the easiest to understand would be to draw 2 schematics. One schematic should show the original WRONG tracks and components (from factory) and another schematic the CORRECT ones.

Thank you for everything.

[free_electron]

does anyone have this thing available as a Atmel studio 7 project ?

i got as far as getting the gcc compiler installed and make and got it to build.
then i installed atmel studio 7. now make under the command prompt no longer works . it throws an error " the system cannot find the path specified".
Everything worked fine until installed studio 7.

i can also not import the makefile into studio 7 using the makefile import tool. it keeps complaining the makefile is not correct.

i'm getting frustrated ... why is this stuff always so bloody complicated.

or is there an other ide with the abilities of visual studio to edit this project ? if so : how to install it and load this as a project ?

thanks

more info :
if i run make on a freshly unzipped tarball it works fine.
if i re-run make without doing anything else i get the "the system cannot find the path specified" error

c:\comptester\make <enter>
..... compiles complete and produces output
c:\comptester\make <enter>
The system cannot find the path specified -barf-


-edit 2-
offending line is 221 : -include $(shell mkdir dep 2>/dev/null ....
i commented it out.

now i can import in studio 7 and the build works there too.

[Feliciano]

Let's say we received a new Chinese T7 clone, a TQFP32 MCU without any marks @16MHz. Is there any way to make an educated guess on what knock-off it can be, LGT8F328P or other?

[indman]

Feliciano,this is not difficult to do. ATmega and LGT8F have detailed documentation.It is enough to look closely at the location of Vcc and GND to determine the processor family.

[Calambres]

What is  the best transistor tester to buy?

Not really interested in hacking it, just in getting the more advanced one of the many options available in the web.

Thanks a lot in advance.

[amershehzadawan]

Hi everyone

first of all i really admire this great project. i salute all developrs of this project.

i am writing this after reading numerous posts in eevblog.com and mikrocontroller.net as well Transistortester documentation and source files at github repository and various firmware files at Yandex drive.

As this project progresses and so far no commercial transistor testor includes new features like continuity tester or ring tester. So i decided to make this testor on Atmega2560. But this chip (and others 644/1280) are not available in my country and Atmega328 has shorter flash memory and so forth i am only left to arduino version of Atmega2560.

The github repository includes Arduino Mega2560 'hex' and 'eeprom' files of newly released version 1.47m and also the source files.
I understood the software options required to be set in config.h or makefile etc.

My questions are

1 What are the hardware changes required for version 1.47m to be make to the arduino mega board to make this testor workable, apart from required 0.1 resistors etc and shorting of two pins to make frequency generator work. Do we have a schematic which includes continuity with buzzer option, zener testor, ring testor etc.
2 How to flash eeprom file to arduino mega.

If someone has already made some progress towards making this testor on arduino Mega2560 please share with me. It would be very helpful.
i know a version 1.13k that has made by plouc68000 two years back. But that does not include newly included fantastic options. And i am unable to translate '.c' to '.ino' files like he did.

your help will make my day

Thanks and regards,

[madires]

What is  the best transistor tester to buy?

Not really interested in hacking it, just in getting the more advanced one of the many options available in the web.

Please see https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf!

[indman]

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4291063/#msg4291063
This clone of T4 is not based on the original ATmega328, but so far on a processor known only to FNIRSI.
The marking on the ATMega328PU-TH case is a fake

Attention! Check with the seller which version of LCR-T4 he will send you, because updating the firmware and upgrading(repair) it is not yet possible! If this is important to you, then this version of the clone has a Chinese APT32F172K8T6 processor installed 

[madires]

1 What are the hardware changes required for version 1.47m to be make to the arduino mega board to make this testor workable, apart from required 0.1 resistors etc and shorting of two pins to make frequency generator work. Do we have a schematic which includes continuity with buzzer option, zener testor, ring testor etc.

We don't have a reference schematic for ATmega2560, but it's fairly simple to add the hardware options. Have you seen the required settings for Arduino in the Clones file and the default pin assignments in config_1280.h?

2 How to flash eeprom file to arduino mega.

Via avrdude for example (either directly via the ISP header, or when the Arduino bootloader is flashed via the USB2serial onboard adapter).

If someone has already made some progress towards making this testor on arduino Mega2560 please share with me. It would be very helpful.
i know a version 1.13k that has made by plouc68000 two years back. But that does not include newly included fantastic options. And i am unable to translate '.c' to '.ino' files like he did.

I've tested the m-firmware on a Mega2560 clone and it works fine. Ports for Arduino use the Arduino HAL which takes away some ressources and therefore limits what is possible, i.e. some features aren't available.

[Calambres]

What is  the best transistor tester to buy?

Not really interested in hacking it, just in getting the more advanced one of the many options available in the web.

Please see https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf!

Thanks, mate!

[amershehzadawan]

Thankyou MADIRES for your prompt reply.

i will check and reply.



Greetings

[masster]

Quote from: amershehzadawan on August 27, 2022, 04:52:34 am

My questions are

1 What are the hardware changes required for version 1.47m to be make to the arduino mega board to make this testor workable, apart from required 0.1 resistors etc and shorting of two pins to make frequency generator work. Do we have a schematic which includes continuity with buzzer option, zener testor, ring testor etc.
2 How to flash eeprom file to arduino mega.

>

[rddube]

Then it's most likely caused by damaged I/O pins. To verify this you can run the self test and look for strange values (or post them here).

I de-fluxed the board, cleaned-up a few things, looked for cracks, shorts, etc.  I didn't find a smoking-gun.

I entered menu mode, select "test", it asks for a short, I install the short, and then nothing happens.  I wait a minute, click the button, and it goes back to the main menu.
I entered the menu mode, select "adjustment", and get the same result as "test".

I entered "show values" I find the following:
Ri- 20 ohms
Ri+ 22 ohms
C0 43 pF
R0 0.2 ohms
Vref 1084 mV
Vcc 5049 mV *
Acomp 0 mV

I had the exact same problem, I changed the AtMega328p and it came back to normal. The AtMega was damaged.

[masster]

@indman
Here is the schematic for Fish-8840TFT updated with the original, wrong circuit schematic for 3.3V.
By the way, the current consumption dropped from 180mA to 26mA after correction.

[indman]

@indman
Here is the schematic for Fish-8840TFT updated with the original, wrong circuit schematic for 3.3V.

There are several variants of the Chinese clone Fish8840TFT - on a blue and green printed circuit board. The option on the green board does not have the same error as on the blue one.Therefore, the correct schematic diagram is on my resource. And I gave you the error variant above in the message #7850. This is a child's mistake, which can be easily detected by any amateur radio operator with experience. If he can't fix such a simple mistake, then the question is why does he need this device?

[Substance]

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg4291063/#msg4291063
This clone of T4 is not based on the original ATmega328, but so far on a processor known only to FNIRSI.
The marking on the ATMega328PU-TH case is a fake

Attention! Check with the seller which version of LCR-T4 he will send you, because updating the firmware and upgrading(repair) it is not yet possible! If this is important to you, then this version of the clone has a Chinese APT32F172K8T6 processor installed 

Thank you for this information. How did you find out that it has an APT32F172K8T6 microcontroller? I recently bought an LCR-T4 and, unfortunately, I received the "V4.1.3_2022/5/18" hardware version of this tester. I immediately saw something unusual about the microcontroller, and I checked how the (+5V) supply connects to the MCU: GND to pin 18 and VDD to pin 19!

No, this cannot be an Atmel ATmega328P, and the supply pins do match the APT32F172K8T6 pinout! Device marking: it does have an Atmel logo (that looks a bit weird), and "MEGA328P / U-TH / 35473D / 220642H" printed/etched on it. No 8 MHz crystal is mounted, and judging from the empty footprints there is a beginning of a serial-to-USB interface (for a CH340N) on the PCB. (I have seen pictures of this PCB version with the CH340N and USB connector mounted.)

Yes, be careful when ordering a new LCR-T4. If you are expecting to receive a component tester that has a genuine Atmel ATmega328P (which you could then reprogram... ) then a little chat with the seller is recommended. However, resellers may not be aware of this fake clone, or resellers may not be interested in customers demanding a product that has genuine components. My seller stated that the reason for this LCR-T4 having different components (with fake device marking on the MCU) is a "chip upgrade", and no comments on the microcontroller device markings.

So, if you have a chance to see the LCR-T4 before purchasing, it is advised to check the bottom side of the PCB to verify whether there is a crystal present. Also the top side of the "V4.1.3_2022/5/18" version PCB has a distinct pattern of traces running straight from ZIF socket to the 1, 2, & 3 test pads. Many customers have bought this product without knowing or complaining about the MCU. Some customers ask (themselves) what this USB connector is all about, but most customers just report that the device is working fine. I just wanted an LCR-T4 to experiment with and to reprogram it, but I now have to search for an original LCR-T4 clone.

[indman]

I just wanted an LCR-T4 to experiment with and to reprogram it, but I now have to search for an original LCR-T4 clone.

Over time, the old LCR-T4 clone will become more and more difficult to obtain, because the deficit and serious rise in price of genuine ATMEL chips will port the author's code to other platforms, which are provided by cheap Chinese CPU variants.
But since the firmware for these processors will not be available yet, consider that you are buying a disposable device.

[Andbro]

Hi,

I have upgraded my AY-AT to 1.47m. But the encoder does not work. I don't see where is my mistake.



CONFIG.h

#define HW_ENCODER
#define ENCODER_PULSES   4
#define ENCODER_STEPS    20




CONFIG328.h
/*
 *  rotary encoder
 */

#define ENCODER_PORT     PORTD     /* port data register */
#define ENCODER_DDR      DDRD      /* port data direction register */
#define ENCODER_PIN      PIND      /* port input pins register */
#define ENCODER_A        PD3       /* rotary encoder A signal */
#define ENCODER_B        PD1       /* rotary encoder B signal */



Thank for your help