$20 ESR LCR Transistor NPN PNP Mosfet Meter

[Shock]

For info and discussion on the cheap Chinese testers click here.

Link to the original open source German project "AVR TransistorTester" by Karl-Heinz Kubbeler:
http://www.mikrocontroller.net/articles/AVR_Transistortester
Same website translated to English
Manual (English) Version 1.12k (2017-01-20)

[Amarbir[Lynx-India]]

Has anyone checked these out or own one?  If they work $20 seems a bargain.
Be interested to know their exact specs such as ESR voltage and frequency range for the DUT.

http://www.ebay.com/itm/170971859171

Well,
     This is The newer Version of Markus Firmware That Has ESR Measurement .It Misses The Case and also the finish quality of a pro product .But i am sure if we peeps can find out a good casing for the same and someone can make a pcb design and learns if and buts of the same its a damn good bargain lol

[firewalker]

Why even bother to hide the mcu?



Alexander.

[Spawn]

I have seen them before, the thing is there is no information about accuracy, on the pictures most capacitors seems to read well till you see the 1000uF one, it shows 673uF on one and 872 on other, lower values are looking good strange enough.

Since I don’t use a LCR that much and still want one in my lab, I ordered UNI-T UT603 just to check out, UNI-T meters give me some confident, but I can imagine the quality is not same every time with UNI-T.

[SeanB]

So it takes 40 seconds longer to realise it is a common MCU............

[Amarbir[Lynx-India]]

So it takes 40 seconds longer to realise it is a common MCU............

SeanB ,
      Boss earlier i used to see they have a dip type mcu.now they have a smd type .I am sure its the same as before only ,Can someone confirm  .This AVR has some brilliant code in there .I am sure the accuracy can be improved by talking into consideration the code and some tweaks  .

[madires]

Has anyone checked these out or own one?  If they work $20 seems a bargain.
Be interested to know their exact specs such as ESR voltage and frequency range for the DUT.

You can find all details (docs, source code) at http://www.mikrocontroller.net/svnbrowser/transistortester/. The original version was done by Markus F. and Karl-Heinz started to improve the design and the firmware. Last year I joined in too with an alternative firmware. Karl-Heinz' current version supports the measurement of inductance and ESR in a very limited way (it's not done the classic way). Since the circuit isn't designed for those measurements it's suprising how much can be achieved with some clever programming. All other tests and measurements work well. The latest changes are about reducing the battery usage by the MCUs sleep mode (sleeping instead of NOPing for larger delays).

Regarding accuracy you'll find some nice graphs in the documentation. Karl-Heinz did a lot of measurements with the tester and a LCR meter. I did too and tried to improve the measurement methods (that's what my alternative firmware is for :-). Capacitors are darn close now with the LCR meter and the tester. BTW, there's a self calibration function in both firmwares. It's strongly recommended since the MCUs and the PCBs may differ a lot.

PS: The MCU of the tester from ebay is an ATmega168. And it seems that the PCB layout could be improved for higher accuracy.

[Amarbir[Lynx-India]]

Has anyone checked these out or own one?  If they work $20 seems a bargain.
Be interested to know their exact specs such as ESR voltage and frequency range for the DUT.

You can find all details (docs, source code) at http://www.mikrocontroller.net/svnbrowser/transistortester/. The original version was done by Markus F. and Karl-Heinz started to improve the design and the firmware. Last year I joined in too with an alternative firmware. Karl-Heinz' current version supports the measurement of inductance and ESR in a very limited way (it's not done the classic way). Since the circuit isn't designed for those measurements it's suprising how much can be achieved with some clever programming. All other tests and measurements work well. The latest changes are about reducing the battery usage by the MCUs sleep mode (sleeping instead of NOPing for larger delays).

Regarding accuracy you'll find some nice graphs in the documentation. Karl-Heinz did a lot of measurements with the tester and a LCR meter. I did too and tried to improve the measurement methods (that's what my alternative firmware is for :-). Capacitors are darn close now with the LCR meter and the tester. BTW, there's a self calibration function in both firmwares. It's strongly recommended since the MCUs and the PCBs may differ a lot.

PS: The MCU of the tester from ebay is an ATmega168. And it seems that the PCB layout could be improved for higher accuracy.

Excellent ,
    can we have some more details about your project with a link or something

[madires]

Excellent ,
    can we have some more details about your project with a link or something

Same link as above (cd Software/Markus). I've also done a modified circuit with a current limiting PWM driver for the LCD backlight (benchtop instead of handheld), which is fully compatible with both firmwares but not uploaded yet.

[Jay_Diddy_B]

Hi,

It seems we have some people on the forum who know this device well 

Can the device measure the ESR of capacitor in circuit or do they have to have to be removed from the circuit for testing?

Many thanks !!

Jay_Diddy_B

[madires]

It seems we have some people on the forum who know this device well 

I guess so :-)

Can the device measure the ESR of capacitor in circuit or do they have to have to be removed from the circuit for testing?

The Transistor Tester doesn't support in-circuit testing/measurements.

[Stonent]

Probably wouldn't be too hard to build an arduino version of this.

[madires]

Probably wouldn't be too hard to build an arduino version of this.

Someone already did but it's got some drawbacks.

[Amarbir[Lynx-India]]

It seems we have some people on the forum who know this device well 

I guess so :-)

Can the device measure the ESR of capacitor in circuit or do they have to have to be removed from the circuit for testing?

The Transistor Tester doesn't support in-circuit testing/measurements.

Hello ,
      Are You Called Mark With firmware Rev 1.05m ? .How Many Different people are making alternative firmware and releasing it in open source  .Also i read the esr accuracy is now 0.01 resolution . Whats the difference between your and that other developer code  ?

[madires]

Are You Called Mark With firmware Rev 1.05m ? .How Many Different people are making alternative firmware and releasing it in open source  .Also i read the esr accuracy is now 0.01 resolution . Whats the difference between your and that other developer code  ?

Yep, Markus with the m-version. The original author is a Markus too :-) The original firmware was written by Markus Frejek and is obsolete by now. Karl-Heinz improved and extended the original firmware and still does. And I joined in by cleaning up source code and adding/changing some stuff. So we got two current firmware forks.

The main differences between both forks is that Karl-Heinz' firmware supports more AVRmega models (with smaller flash size), inductance and ESR measurements (in a limited way). My version has a changed user interface, a milli-ohm measurement and some measurements are done in a little different (better?) way. For example I wasn't happy with Vf (Vbe) of BJTs, it was much to high. So I tried something else and Karl-Heinz improved his solution too. The nice thing is that Karl-Heinz and I learn a lot from each other.

[Amarbir[Lynx-India]]

Yep, Markus with the m-version. The original author is a Markus too :-) The original firmware was written by Markus Frejek and is obsolete by now. Karl-Heinz improved and extended the original firmware and still does. And I joined in by cleaning up source code and adding/changing some stuff. So we got two current firmware forks.

The main differences between both forks is that Karl-Heinz' firmware supports more AVRmega models (with smaller flash size), inductance and ESR measurements (in a limited way). My version has a changed user interface, a milli-ohm measurement and some measurements are done in a little different (better?) way. For example I wasn't happy with Vf (Vbe) of BJTs, it was much to high. So I tried something else and Karl-Heinz improved his solution too. The nice thing is that Karl-Heinz and I learn a lot from each other.

Well,
     Whats the point then if each other take suggestions from each other and improve the code .Then why have two different tracks  .I did read the code and the project in the afternoon today and i would say that you should not stick to the hardware frejek made  .Might be its time for a little redesign and then taking the project to a higher level  .Frejeks initial eye of attraction was a project my jeremy from peak electronics uk .Whom i am proud in representing as national distributor in india .They have taken DCA55 to a Higher Level ,They Have the DCA75 now and this is with computer interface  .Even Dangerous Prototypes has a project just like this .Hence shake up your leg and take it to a higher level .Sign i still do not know about microcontrollers yet .I am learning the veteran 8051 right now and it will take a while IMHO  .Then migration to other platforms etc would be easy .

[sonnytiger]

I got one of these months ago from some guy in china, about the same price, it did not work very well, it measured inductance at a quite low value and capacitors were lower then they should be as well. I tested multiple 680uH inductors for example and all tested much more than 10% below their rated value.

[Amarbir[Lynx-India]]

I got one of these months ago from some guy in china, about the same price, it did not work very well, it measured inductance at a quite low value and capacitors were lower then they should be as well. I tested multiple 680uH inductors for example and all tested much more than 10% below their rated value.

Well,
      Could You Compare it with a LCR Meter As Inductance Is Not This tools forte

[madires]

Whats the point then if each other take suggestions from each other and improve the code .Then why have two different tracks .

If you read my readme file you'll find the answer :-) Or just call it evolution or improvement by competition. 

I did read the code and the project in the afternoon today and i would say that you should not stick to the hardware frejek made  .Might be its time for a little redesign and then taking the project to a higher level  .Frejeks initial eye of attraction was a project my jeremy from peak electronics uk .Whom i am proud in representing as national distributor in india .They have taken DCA55 to a Higher Level ,They Have the DCA75 now and this is with computer interface  .Even Dangerous Prototypes has a project just like this .Hence shake up your leg and take it to a higher level .

The firmware should stay compatible with the old circuit design. If we would change the hardware design every six months for new features we would make a lot of users unhappy. This is a open hardware and software project, not a commercial venture. There are some ideas about a Tester+ with improved hardware but it would be much more complex (a lot of external components) and SMT-only. Since there are a lot of starters in the userbase I'm unsure if a Tester+ would be a great idea for them.

Sign i still do not know about microcontrollers yet .I am learning the veteran 8051 right now and it will take a while IMHO  .Then migration to other platforms etc would be easy .

Not as easy as you think. The AVRmega runs nicely at 5V which is a good compromise for testing a lot of components. More powerful MCUs run at 3V which is too low and requires a lot of external components to drive 5V or even higher voltages with a decent current. Some measurements done with the AVRmega exceed the maximum I/O current. You have also to deal with MCU specific details like the internal resistance of I/O pins and so on. That's just the hardware. Optimizations for higher accuracy are based on the MCU. Another MCU family causes a complete rework of those optimizations.

[Amarbir[Lynx-India]]

Well,
    Any links for that tester+ concept you are referring to markus .Have you seen some other component tester design and projects .i know a few

1 : This project
2 : Dangerous prototypes - i think its going to be done with now IMHO
3 : semtest - one hell of a project @ silicon chip and this months epe uk also has this project its three part project  .

[madires]

Well,
    Any links for that tester+ concept you are referring to markus .

That's just an internal/private discussion at the moment.

Have you seen some other component tester design and projects .i know a few

1 : This project
2 : Dangerous prototypes - i think its going to be done with now IMHO
3 : semtest - one hell of a project @ silicon chip and this months epe uk also has this project its three part project  .

Yes, DPs project is based on a PIC. But I didn't know about semtest (got no subscription). Let's see. It provides quite high voltages but only 1mA drive current. That's much too low for power devices, like a 2N3055.

[Amarbir[Lynx-India]]

Markus ,
    i got a iphone and i when to store and i could download one version of EPE free .The Feb issue has part 1 of semtest all free

Ps :  Everyone a little thank you for this info is appreciated hee hee 

[madires]

There's a firmware fork and a shield for the Arduino now at http://www.pighixxx.com/lavori/ardutester/. Alberto used my code and is adding the ESR and inductance measurement functions from Karl-Heinz.

[triac]

I purchased this tester and found it to be quite accurate.Latest version. Certainly worth $20.
With the exception on large capacitors which i could not verify as my HP tester is down. but large capacitors drift and vary a fair amount so a close call is probably OK.
It is quite impressive that so many functions are packed in to a small unit.
I note some are available in a box with a Zif connector I can make this modification my self even some strip board for the surface mount components.
The board has some connections for USB and a battery charging circuit, any body have info on this?

[madires]

I purchased this tester and found it to be quite accurate.Latest version. Certainly worth $20.
With the exception on large capacitors which i could not verify as my HP tester is down. but large capacitors drift and vary a fair amount so a close call is probably OK.
It is quite impressive that so many functions are packed in to a small unit.

And it's not finished yet :-) Currently I'm working on an improved diode detection.

I note some are available in a box with a Zif connector I can make this modification my self even some strip board for the surface mount components.
The board has some connections for USB and a battery charging circuit, any body have info on this?

Unfortunately not, since that part is added by the PCB designer, it's not an "official" feature.