Chinese TC1 transistor tester

[distefanom]

Hi guys
I bought this transistor tester from china.
It worked well until I tested a 1000uF capacitor which was discharged. But immediately the instrument TC1 turned off.
I've seen there are other discussions on this machine, but one seems to me not enough discussed.
On my TC1 I tried to search the faulty component and I've found the DZ2 in short circuit.
I removed it and checked every other component around: all seems ok
But if I turn it on, It displays a "ghost battery" of 1,42V applied at terminals 1&2 but of course, there isn't (see images).
Also, if try to measure any component I get always the same image.
If I think to change the microcontroller, is there any firmware available? Where I can download it?
Please let me know, thanks
Mario

[PKTKS]

There are more than a dozen  firmwares available..

Try to check which version matches your hardware
and be careful with the FUSES

https://www.mikrocontroller.net/articles/AVR-Transistortester

Paul

[PKTKS]

ALAS...

The original mamut thread is still alive and well

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

And new firmware  available with the olders..
https://github.com/madires/Transistortester-Warehouse/tree/master/Firmware/m-firmware
https://github.com/svn2github/transistortester
https://github.com/atar-axis/tc1-u4

Take your time reading stuff

Paul

[PKTKS]

This picture is part of Markus bundle  software package.

It should help you to find a primary reference for your board..

The newest firmware is already in the URI above

Paul

[distefanom]

I want to thank you PKTKS for your kind answer, I've already tried to download those GITHUB links -but- there's a problem 4 me:
Several of those files, I cant' be downloaded, and, more of all, I don't know how to compile the firmware.
I'm not a programming nerd, so I have difficulties trying to compile these things.
Also you finally suggest to be careful with the programming fuses...
Since those are ALOT fuses inside the microcontroller, I really don't know which is which and their correct configuration I need to set them to be able to program the new microcontroller I bought AND to be able to reprogram it anytime in the future. (In case it will break again)
I'm a simple user of the TC1 tester, not making them in any production... I simply want to repair this valuable tester... don't want to do anything else with it...
Believe me, all this is a mess as it is, from my pov.

I'm not a master in all this, unfortunately.
similarly, that little PCB to replace the U4... I don' have a PC equipped & power enough to handle also kikad to read those files (I already have a mess of applications on my PC, that I use for a lot of other jobs, and don't have enough time to learn new programs.
The electrical scheme of that little PCB would be already enough for me to replicate it.
Consider that I'm 62!
So if you or someone else could link me:
- the already compiled firmware (any version, .hex or .bin) compatible with the U4 hardware PCB modification;
- could tell me how to set the fuses to be able to use the thing, and can read/reprogram it eventually anytime AFTER;
- and finally could give me a screenshot of the schematic to replace U4, I would be TOTALLY GLAD.
That's all I need.
Thanks for the attention.
Mario

[PKTKS]

The whole packages contain the firmware already compiled...

But I got you very well - in that point of the
learning curve this task is way too complicated..

In simple terms you need to find the proper firmware version.
and using AVRDUDE... flash the atmega using ICSP tool.

A newbie with decent skills in arduino should be able to do that..

Using GIT the older and the newer firmware can be retrieved

OLD: git clone git://github.com/svn2github/transistortester

NEW: git clone git://github.com/kubi48/TransistorTester-source


Having the compiled firmware 1st step..
flashing that on the MCU using an ICSP programmer tool with AVRDUDE...

That are the required steps..

The grunt (really grunt) work was done already by Markus and other folks.

Paul

[distefanom]

Sorry... maybe I'm dumb as goat...
what is git?
The links you posted are not active links, and when I copy/glue them into the address bar I get the very same page...
Again:
- I need the already compiled firmware (any version, .hex or .bin) compatible with the U4 hardware PCB modification;
- how to set the fuses to correctly program the microcontroller, and can read/reprogram it eventually anytime AFTER?
- and finally could give me a screenshot of the schematic to replace U4?

please help!

[PKTKS]

Sorry... maybe I'm dumb as goat...
what is git?
The links you posted are not active links, and when I copy/glue them into the address bar I get the very same page...
Again:
- I need the already compiled firmware (any version, .hex or .bin) compatible with the U4 hardware PCB modification;
- how to set the fuses to correctly program the microcontroller, and can read/reprogram it eventually anytime AFTER?
- and finally could give me a screenshot of the schematic to replace U4?

please help!

GIT is a developer framework.
http://git-scm.com/

There are TONs of "front-ends" applets to interface with GIT.
Any applet will understand the GIT URL.

Regarding SCHEMATICS..  there so many as there are versions of the software.
Every bundle already contains one or two schemas...

I can attach one here but hardly will fit all the boards out there..
it is close.. nevertheless it helps...

You need to climb the learning curve.. so do not skip steps..

when in doubt ... ask more here...
the folks here when having time will drop a bit or 2

Paul

[distefanom]

It's ok for me 4 the learning curve, I can do it.
but it seems to me, seeing your posts, that we're talking about of two different devices.
Those schematics you posted are NOT of the tester I have to repair.
I want to repair the TC1 tester. its images are the ones I've posted at the beginning of this thread.
Attached again here for your commodity.
In your picture-link.pdf file, you call it "m644_T4".
But take into consideration that the microcontroller inside is an ATMEGA324PA.
This is the exact tester I need to repair

[PKTKS]

No they are not..
I have no means to know which one fits...

I have half dozens models myself and NONE fits
perfectly the schemas.. the ones posted are the original
ones bundled already with Markus orginal stuff.

All boards you find EBAY/ALIX are clones .. modified clones.

I need to adapt mines to fit..
you need to adapt yours...

This is your first one..

I have half dozen..  they change over time and got better..
Nevertheless you can use the older and fix them fine as well

The steps will not change..

Hardly you will find a perfect match schema..
close enough is good enough..

the whole gizmo is simple..
the software is complicated..

The GIT url contains a full manual.. it will take you 15 days just to read ...
Paul

[cdev]

I still get so much use out of mine, possibly its because its so easy to use and always gives a usable and thought provoking answer of what it sees the DUT as being.  Its not always what I think its going to tell me. Not at all.

[nigelwright7557]

I still get so much use out of mine, possibly its because its so easy to use and always gives a usable and thought provoking answer of what it sees the DUT as being.  Its not always what I think its going to tell me. Not at all.

While battery powered transistor testers do have their uses the test current can be little more than useless.
Some use as little as 2mA to test a transistor.
Normal working current for some transistors can be amps which is a totally different area of operation.
Hfe at 2mA can be very different to Hfe at 5 amps.

[Kim Christensen]

This is the exact tester I need to repair
TC-1 schematic.JPG

Did you create the schematic yourself by reverse engineering your broken unit?

[distefanom]

Sorry for my late answer, but the schematic is exactly the one I posted above