Tuesday, January 12, 2016

do it yourself ESR meter

Hi Marcus
This file is still too big, 57mb!
Also noted you did not use stripe board and therefore I will not be able to check any errors because you have used a different board.
Which country are you from?
Regards Humphrey

Sorry to hear that. I'm here in the Philippines

Hi Marcus,
No problem, actually the reason I asked your country is because I wanted to see if I can send you mine which I did as do it yourself project.

Using the template I send you I assembled it and worked first time, I remember a guy from Kenya who did it and never worked and invited me to his place to check out why his meter is not working.

I was surprised to find he has used a normal linear transformer and I told me to use the charger transformer and it worked till today.

so I think even you are missing something small, in fact with the materials ready and using my template without thinking because the template is tested and works you will find how easy it is for it to work.

All my template which I share online works, in fact I myself I started as do it yourself guy and through that I leant a lot.

So don’t give up, just do it one more time but be sure you have used my template so that in case you get problem I can always give you support.

All the best my friend

Regards Humphrey


I finally found it out! I realized that I was using a breadboard (the one for, solder less, temporary prototyping) to connect the 9v battery to my main circuit. I wondered if parasitic inductances and capacitances can affect my circuit, which is notorious on breadboards. So I tried to connect the power supply directly, and then stared to my meter whole day if it will go unstable. And it worked!!!

I reworked the whole meter to make the final build. Now it works flawlessly. I know now why people don't use a breadboard to prototype analog circuits.

Here's photos of my build. I didn't mind to add a project box any longer. It looks like a Arduino that way. I'll just simply add a container to keep the dust off

Thanks for the hope Humphrey. I know, I shouldn't give up either. I know there's something on the circuit waiting for me to be discovered, which I have.

Congratulations Marcus, very professional work here.
Regards Humphrey

Wait, 1 last thing. Can I use this to measure ESR of a battery like the Blue ESR meter? Although I'll be using this for caps but I'm still wondering...

Never try that at home... Haha  I have never tried that but am sure it will not work.
Regards Humphrey

OH! Okay, okay, thanks, really thanks! Good thing I ask!


Final product, ready to work
For those who want to make their own click here

For do it yourself fly-back tester click here.


  1. Hi Humphrey
    thanks for your article it is very useful

  2. you are really saving the world of poor technicians.