$20 LCR ESR Transistor checker project

[indman]

In the last audits of a firmware the author added the new mode of measurement of inductance. It is necessary for operation of this mode in case of calibration (Selftest mode) there will be a parameter "Cap for L meas?" - the condenser for measurement of L.
in case of which it is necessary on T1 - T3 to connect capacity =10nF to 20nF which in case of measurement needs to be connected further parallel to the measured inductivity
In case of measurement on T1 - the inductivity T3 with parallely connected condenser is displayed:
1 - 3  0.02- - resistance in Ohm.
600nH if 10.7nF - inductivity in mH (millihenry) µH (microhenry) of nH (nanohenry) with if capacity added parallely in nF (nanofarad).
1985kHz Q=2.5 - frequency (resonant or the frequency of a circuit) in kHz (kilohertz) and Q (good quality of L).

[yo0]

yo0,try this firmware for the tester. I hope everything will work!

thank you very much!, works as intended, just i having trouble with calibration, as i understand i need a 10-20 nf cap, need to find one

and the font you choose looks great!!

you plan to release new versions this model in the future?


best regards

Pio

[indman]

yo0, I am glad that at you the firmware earned!
You can use for calibration any capacity from 10nF above, it is only desirable that it was high quality.
If fresh firmwares for your clone are necessary, I will help!
I collect and I compile firmwares for different clones, on Yandex resource a disk I have a space for them. You can look at them according to the link
https://yadi.sk/d/yW8xa5NJgUo5z

[yo0]

yo0, I am glad that at you the firmware earned!
You can use for calibration any capacity from 10nF above, it is only desirable that it was high quality.
If fresh firmwares for your clone are necessary, I will help!
I collect and I compile firmwares for different clones, on Yandex resource a disk I have a space for them. You can look at them according to the link
https://yadi.sk/d/yW8xa5NJgUo5z

thank you very much again, i already bookmaked your repository, i will visit it for any update.

thank you again!

best regards

Pio

[nbritton]

Can someone post an executive summary of this 87 page thread? I would like to know how I can build one or where I can pickup one of these devices.

[bitseeker]

There are so many to choose from. Some are assembled, some are in kit form.

Here's a high-level summary of some of the variations:

• Compact, 2-line character LCD display: some use 9-volt, some use rechargeable battery.
• Graphical LCD display: some have single button (test/on), some have two (test/on, off), some of the newer ones have a rotary encoder that you can press for test/on.
• There are different models of microcontrollers on them: Atmega 8, 168, 328, 2560; some are socketed DIP (easy to replace if you fry it because you forget to discharge a cap before testing), others are SMD.
• The ones with at least Atmega328 can use the extra features of the latest firmware such as function generator and frequency counter.
  
• Some are built into a case or have a separate case that they fit into.

There are many other details, but hopefully this will get you oriented.

[Messtechniker]

Here's a high-level summary of some of the variations:

6. With or without ISP connector.

In the case of non-socketed processors you will need the ISP connector for flashing.

Since I wanted to help development of this thing, I went for the GM 328. It has a socketed processor.
So it is easy to flash externally and replace if damaged. Can easily happen when connecting
large capacitors which are still charged. A protection circuit would prohibit measurements
on other components.

Yours Messtechniker

[bitseeker]

Thanks for the additional info, Messtechniker.

I got my kit today (socketed 328 with graphical LCD and rotary switch). Weekend project!

[yo0]

hello, somebody know the unpopulated parts of this tester pcb are intended for?


best regards


Pio

[quantalume]

some are socketed DIP (easy to replace if you fry it because you forget to discharge a cap before testing), others are SMD.

This is a very good point. In fact, I would not recommend anyone buy a version without either a socketed controller or protection on the input pins.

[indman]

hello, somebody know the unpopulated parts of this tester pcb are intended for?

yo0, these details are necessary to provide a supply and illumination for displays of different types. If everything works for you, there is no need to solder them

[yo0]

hello, somebody know the unpopulated parts of this tester pcb are intended for?

yo0, these details are necessary to provide a supply and illumination for displays of different types. If everything works for you, there is no need to solder them

thank you for the info!


Pio

[Electro Fan]

Don't know if this one has been nominated in the tester + frequency generator category:
http://www.amazon.com/gp/product/B00OOQC2E8/ref=pd_luc_rh_top_sim_03_03_t_img_lh?ie=UTF8&psc=1

[indman]

Don't know if this one has been nominated in the tester + frequency generator category:
http://www.amazon.com/gp/product/B00OOQC2E8/ref=pd_luc_rh_top_sim_03_03_t_img_lh?ie=UTF8&psc=1

Any tester with a new firmware from Karl-Heinz Kübbeler contains this function of the generator

[wasyoungonce]

Don't know if this one has been nominated in the tester + frequency generator category:
http://www.amazon.com/gp/product/B00OOQC2E8/ref=pd_luc_rh_top_sim_03_03_t_img_lh?ie=UTF8&psc=1

Yeah I have one...from fleabay  works ok but no in circuit programming port.
Here it is.... in a feable box.  Had to remove the display SIL header and lower the display (so it wasn't too high wrt the ZIF socket), butcher the box and heat bend the zif socket actuator arm to fit.

What can I say...it works, no prizes though.

[amirtebyan]

Hi guys:
My english is not very good.

I have some problems with my tester.
I use 1.12k ver with graphic lcd st7920 and atmega2560.

1_ some times When no component connected and i press test key a capacitor in range of micro farad is shown.

2_ When "not calibrated" massage is shown on lcd i do calibration prosses and after finishing it this massage shown again.

3_ when i connect any inductor and press test button lcd dosen't show any thing and i should reset microcontroller for back to normal opration. This happen some times when i connect larg capacitor to tester like 2200 uf .

Do you know the reason?

[klaus11]

yo0, I am glad that at you the firmware earned!
You can use for calibration any capacity from 10nF above, it is only desirable that it was high quality.
If fresh firmwares for your clone are necessary, I will help!
I collect and I compile firmwares for different clones, on Yandex resource a disk I have a space for them. You can look at them according to the link
https://yadi.sk/d/yW8xa5NJgUo5z

with open programming spl7 extension schemes.

[indman]

with open programming spl7 extension schemes.

Diagrams in the spl7 format open the sPlan7.0 program. Link to this software:
http://abacom-online.de/uk/html/demoversionen.html

[madires]

1_ some times When no component connected and i press test key a capacitor in range of micro farad is shown.

2_ When "not calibrated" massage is shown on lcd i do calibration prosses and after finishing it this massage shown again.

3_ when i connect any inductor and press test button lcd dosen't show any thing and i should reset microcontroller for back to normal opration. This happen some times when i connect larg capacitor to tester like 2200 uf .

Do you power the tester with a battery or a switching mode power supply?

[klaus11]

with open programming spl7 extension schemes.

Diagrams in the spl7 format open the sPlan7.0 program. Link to this software:
http://abacom-online.de/uk/html/demoversionen.html

Thank! 

[amirtebyan]

Do you power the tester with a battery or a switching mode power supply?

I use switching power supply with 9v 1000mA output.

[madires]

Do you power the tester with a battery or a switching mode power supply?

I use switching power supply with 9v 1000mA output.

Please try a battery or a linear regulated power supply.

[amirtebyan]

Please try a battery or a linear regulated power supply.

Thanks I will try it.

I have another questions to
1- When I connect capacitors like 2200uF and 100uF are shown  much lower (1.7mF and 79uF). what is the reason?
2- I use atmega2560 and i set clock source 8Mhz internal rc oscillator , is it ok? how should i set the other fuese?

[madires]

1- When I connect capacitors like 2200uF and 100uF are shown  much lower (1.7mF and 79uF). what is the reason?

I'd think it's caused by normal tolerances.

2- I use atmega2560 and i set clock source 8Mhz internal rc oscillator , is it ok? how should i set the other fuese?

For a higher accuracy I'd recommend an external crystal. The fuse settings are in the setup.mk file (included by Makefile).

[bitseeker]

1- When I connect capacitors like 2200uF and 100uF are shown  much lower (1.7mF and 79uF). what is the reason?

Check what's the tolerance for those capacitors. For example, if they're 10%, then the 2200uF can be from 1980-2420uF (2200+-220uF). Looks like those two are a little over 20%, which might be close enough for 20% caps if your tester is a little out of calibration.