$20 LCR ESR Transistor checker project

[intrax]

What about free-electron's board as mentioned in this thread… Will it ever appear? If not I will go with one of the newer at328 boards from our chinese 'friends'.

[Shock]

What about free-electron's board as mentioned in this thread… Will it ever appear? If not I will go with one of the newer at328 boards from our chinese 'friends'.

Well most of us own at least one so I doubt anyone is in too much of a hurry.
But a nice upgradable board design that offers all the features would be nice.

[intrax]

Could someone tell me what board this esr meter is based upon: and where to look for the layout?

[Hydrawerk]

The Karl Heinz Kubbeler version is IMHO better.

[casinada]

Intrax,
http://www.mikrocontroller.net/articles/AVR_Transistortester
It is in german, just let google translate it for you
All the information you need is there.

[simonmc]

I received my version yesterday, i will post some pics but i will have to resize them.

 It has a 168 installed and is running v1.07 i believe. I have to say i'm very impressed and the unit will prove very useful to me. I did have some problems with my order, it seems the first one the seller sent, got lost and the seller posted out a second one to me. I don't know if the one that has just arrived is the first or second one though so i may end up with another one in the next couple of weeks!

I will replace the 168 with a 328 when i get the time and replace the reg and resistors with better items and add some better decoupling to the micro. The fitted zener seems to be a smt 4.3V one. Can anyone recommend a decent LDO with the same footprint as the mounted 7805?

The ZIF socket is not the best quality but it is usable and if it breaks i will replace with a 3M one. I de-soldered the LCD and added a socket so that it is removable. I also added some stand off's to act as feet. I still have to add the 6 pin ISP header.

As regards to the latest firmware, can you good people confirm i have the correct tool chain to compile and programme the device. I have Amtel studio 6.1 installed, extreme burner AVR, and will be ordering a couple of the cheap ebay USB ISP devices that are on ebay. Is this all i need?

EDIT:- Added pics

[madires]

I will replace the 168 with a 328 when i get the time and replace the reg and resistors with better items and add some better decoupling to the micro. The fitted zener seems to be a smt 4.3V one. Can anyone recommend a decent LDO with the same footprint as the mounted 7805?

A zener? If a standard zener is connected to PC4 please remove it. And in case you like to have a voltage reference replace the zener with a LM285 or LM4040 2.5V. I'd recommend to use the MCP1702 as LDO, even with the different pinout. It works great and you don't need the external voltage reference.

As regards to the latest firmware, can you good people confirm i have the correct tool chain to compile and programme the device. I have Amtel studio 6.1 installed, extreme burner AVR, and will be ordering a couple of the cheap ebay USB ISP devices that are on ebay. Is this all i need?

Atmel Studio is fine. Can't say anything about extreme burner AVR since i'm using avrdude. And for the programmer I'd get something like the Diamex ALL-AVR which does ISP, PDI and TPI (USB is compatible with AVRISP-MkII).

[simonmc]

A zener? If a standard zener is connected to PC4 please remove it. And in case you like to have a voltage reference replace the zener with a LM285 or LM4040 2.5V. I'd recommend to use the MCP1702 as LDO, even with the different pinout. It works great and you don't need the external voltage reference.

It looks like a zener judging by its code (431, mounted just above and to the right of the micro in the second pic i posted) and is connected to PC4. Should i remove that part even though i dont have a reference or ldo on hand till i get to work?? Does this zener actually decrease the accuracy of the cct or does it do nothing at all?

[madires]

It looks like a zener judging by its code (431, mounted just above and to the right of the micro in the second pic i posted) and is connected to PC4. Should i remove that part even though i dont have a reference or ldo on hand till i get to work?? Does this zener actually decrease the accuracy of the cct or does it do nothing at all?

Hmm, could be a TL431. Are two pins shorted (cathode and ref)? A TL431 should be fine too. Though, we don't know it's accuracy (AFAIK you can get 2%, 1% and 0.5% types). It's all about the ADC's voltage reference. Either you got an accurate and stable 5V regulator or a proper external voltage reference. In the first case the tester assumes that 5V are 5.000V. In the latter case the tester uses the external voltage reference to calculate the offset of the 5V rail. For a 7805/78L05 you'll need the external voltage reference because the 78 is not accurate enough. The MCP1702 LDO for example has an accuracy of 0.4%. An external voltage reference with a poor accuracy will make the tester less accurate.

[simonmc]

looking at the datasheet it could very well be a TL431. Yes the cathode and ref pins are shorted.

[Aragorn]

Is there a file download section here for the tester Pcb layouts? I just built the tester, would like to cleanup the project. Is anyone selling blank pcbs?

Thanks,
-d

[casinada]

Aragonrn,
There are many different versions of the tester as is discussed here:
http://www.mikrocontroller.net/articles/AVR_Transistortester
All the information can be found there.
Assembled and ready to go testers can be found on ebayy for as little as $13
There is a member of the eevblog that might make a board soon.
If you have questions after reading all the info available here and the site mentioned above, please come back and ask.

[Aragorn]

Thank you, just ordered 2 from China. Not exactly what I wanted, but for the price, I couldn't build one myself.

-d

[retrolefty]

Well I bought this one 4 days ago from Hong Kong and it arrived today, that's a record for me as normally Asian E-bay shipping to me on West Coast USA is 10-12 days.

 It's got the 328P avr chip in a socket. No ISP connector. I put a couple of npn, pnp, caps and it identified them all. Then I dug out my 250 .01% reference resistor and it read it as 249.5 so I'm pretty impressed.

I added four 1/2" nylon standoffs so it would sit flat and wrapped the 9 volt battery in plastic tape and rubber banded it to the back of the PCB. Who needs a case, not me. 

http://www.ebay.com/itm/291041497713?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

[AintBigAintClever]

If you want the latest manuals go to http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/ and download the tarball (I've not found a way of viewing the PDFs within the browser, this seems to be the quickest way). German and Russian manuals are available if you go up to the parent folder.

Well worth it if you think this is just a component tester. Extra goodies are a few button presses away

[Mr Smiley]

Hi all,

Which version does the high 20,000uF capacitor readings as stated by the below ebay listing

http://www.ebay.co.uk/itm/New-Transistor-Tester-Capacitor-ESR-Inductance-Resistor-Meter-NPN-PNP-Mosfet-/251210970850?pt=LH_DefaultDomain_0&hash=item3a7d5736e2

Many thanks

 

Also, could this version be upgraded to the latest version just by upgrading the processor 

http://www.ebay.co.uk/itm/NEW-TRANSISTOR-TESTER-NPN-PNP-MOSFET-THYRISTOR-DIODE-RESISTOR-CAPACITOR-METER-/261192428249?pt=LH_DefaultDomain_0&hash=item3cd0482ad9

as it only costs 12 dollars and has a socketed processor


 

[madires]

Which version does the high 20,000uF capacitor readings as stated by the below ebay listing

Basically all do (theoretically up to 100mF).

Also, could this version be upgraded to the latest version just by upgrading the processor 

Any clone can be updated to the latest firmware, but only the ATmega328 can run the firmware with all features enabled. The other ATmegas with less flash memory got a stripped down firmware.

[Mr Smiley]

Hi,

Thanks, what gets me unsure sometimes is when China/Hong Kong put mF instead of uF 

The first ebay copies state upto 20,000uF and others, the latest version say 100mF ( mili or micro  )

So in the last link a posted, upping the atmega8 to a atmega328 will give it all for £7 uk pounds plus a 328 

 

[retrolefty]

If you want the latest manuals go to http://www.mikrocontroller.net/svnbrowser/transistortester/Doku/tags/english/ and download the tarball (I've not found a way of viewing the PDFs within the browser, this seems to be the quickest way). German and Russian manuals are available if you go up to the parent folder.

Well worth it if you think this is just a component tester. Extra goodies are a few button presses away

Is it possible someone could simple post the english PDF manual or a direct link to the same? I don't seen to have a tarball compatible program to process that.

[Mr Smiley]

Hi,

The file is 1.5Mb, the file you want is 1.3Mb, but the limitation here is 1Mb.

7zip will open the file for you but you need two steps


1/ right-click on the example.tar.gz file and choose 7-Zip --> Extract Here from the context menu.
   
2/  then take the resulting example.tar file and the right-click again and choose 7-Zip --> Extract Here from the context menu.

If you download 7zip, make sure you don't get the one with hidden junk.

 

[amtpdb]

How do you make sure you did not get the one with JUNK?

[Retep]

Also, could this version be upgraded to the latest version just by upgrading the processor 

http://www.ebay.co.uk/itm/NEW-TRANSISTOR-TESTER-NPN-PNP-MOSFET-THYRISTOR-DIODE-RESISTOR-CAPACITOR-METER-/261192428249?pt=LH_DefaultDomain_0&hash=item3cd0482ad9

as it only costs 12 dollars and has a socketed processor

Looking at the photo this one seems to have a ATMega8 processor. The ATMega8 processor doesn't have enough memory for all the features in the later software versions. Personally I would spend a few dollars more to get one with a (socketed) ATMega328 processor.

[retrolefty]

How do you make sure you did not get the one with JUNK?

 Same question. And does no one have the english manual pdf hosted somewhere?

[Mr Smiley]

Hi,

I've looked around and there are no reports of bloatware included with the install.

I use Linux, otherwise i would have installed it to see  When i did use windows, i used 7zip.

As for the Atmega8, yes i knew that, that's why i wondered if just popping in a 328 would be all that was needed, i was also thinking of using one of those cheep Clones, the arduino pro mini, changing the xtal to 8Mhz and adding a lcd which i have a few of 

 

[intrax]

Can any of these ones do 'in circuit' testing of (discharged) capacitors or is there an easy fix possible so that they can?