Author Topic: 5 Transistor ESR Meter Design (Read 310608 times)

old-jo · « **Reply #375 on:** December 21, 2022, 11:37:41 am »

Hello everyone.

I finally completed my build of the 5 Transistor ESR Meter.

This is the final build:

This was the internals before it was put inside the enclosure:

In my build I powered the circuit directly from 4 AA cells without the 5V regulator. It appears to be working fine.

Thank you Jay_Diddy_B for the design!

I am looking forward for the new and improved ESR meter design.

Jay_Diddy_B · « **Reply #376 on:** December 21, 2022, 02:51:07 pm »

Quote from: old-jo on December 21, 2022, 11:37:41 am

Hello everyone.

I finally completed my build of the 5 Transistor ESR Meter.

Snip ...

It looks great!!

You should be able to modify that to the new version.

Jay_Diddy_B

Jay_Diddy_B · « **Reply #377 on:** December 30, 2022, 12:04:00 am »

Hi group,

I promised an update after I have tested the prototype.

I received the partially assembled board assemblies from JLCPCB. This is the first time that I have ordered assembled boards. The process was very smooth. I chose only to have them install parts in their basic library. You can have them install other parts, but there is a $3.00 per line item charge.

Here is a picture of the assembled board.

Schematic

This is the revised schematic:

The changes are:

1) The regulator was changed from the 7805 to AZ1117-5. This has a lower dropout voltage, but requires larger capacitors.

2) C4 was added. This is a d.c. blocking capacitor to allow shorted capacitors to be detected.

3) The circuitry Q4 and Q5 was added. The LED will illuminate if the capacitor being tested is less than 25 $\$\Omega\$$ .

The rest of the circuit is the same as the original version.

Notes: This was redrawn in KICAD version 5.00 there is no connection between the component references in this version and the previous version or the LTspice model.

R22 must be chosen depending on the resistance of the 50uA meter movement. In my case the resistor is around 18k $\$\Omega\$$

If you search 5 transistor ESR meter on the internet you get quite a few hits from all around the world. A lot of people have done the right thing and given credit back to the original design presented in this thread. Other people have not. It would be nice if you make a copy or a derivative to credit the original work.

Files

I have attached a zipfile that should contain enough information to open the project in KICAD. Let me know if anything is missing.

I have also attached the LTspice model.

Regards,
Jay_Diddy_B

picture.PNG (1753.64 kB. 1196x903 - viewed 5215 times.)

7 transistor ESR meter with sc detector.asc (7.7 kB - downloaded 471 times.)

Jay_Diddy_B · « **Reply #378 on:** December 30, 2022, 12:11:09 am »

Hi group,

Quote from: kripton2035 on December 20, 2022, 03:23:16 pm

another possible improvement : add the same high voltage protection than on the esr to voltmeter adapter...

Kripton2035 asked if it was possible to implement the same high-voltage protection that I used in this project:

https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/

The circuit used has ac coupling capacitor on the source and the receiver.

I couldn't work out how to do this and the dc path that is required to detect a shorted capacitor.

Jay_Diddy_B

kkamel · « **Reply #379 on:** December 30, 2022, 04:37:44 am »

Thanks Jay I will try the new board, I will order it partially assembled from Jlcpcb as you did, but why didn’t you add it as a project in PCBWay with your name to get the proper credit you deserve.

BravoV · « **Reply #380 on:** December 30, 2022, 02:32:51 pm »

Jay_Diddy_B,

Excellent update, thanks.

Suggesting to update the 1st post pointing about this new version, as its buried deep in this long thread.

Jay_Diddy_B · « **Reply #381 on:** December 30, 2022, 10:54:19 pm »

Quote from: BravoV on December 30, 2022, 02:32:51 pm

Jay_Diddy_B,

Excellent update, thanks.

Suggesting to update the 1st post pointing about this new version, as its buried deep in this long thread.

Good idea!!

I have placed a link in the first message to the latest version.

Regards,
Jay_Diddy_B

Chris56000 · « **Reply #382 on:** January 09, 2023, 04:26:11 am »

That meter scale software is rising distinctly alarmingly in price – the author is now wanting 55 USD for it – it was 42 USD when I looked this time last year!

Chris Williams

pgr2002 · « **Reply #383 on:** February 02, 2023, 03:57:06 pm »

If there is a thru hole pcb design with silkscreen it will be more helpful for 7 transistor esr meter

quadtech · « **Reply #384 on:** February 03, 2023, 01:34:57 pm »

Quote from: pgr2002 on February 02, 2023, 03:57:06 pm

If there is a thru hole pcb design with silkscreen it will be more helpful for 7 transistor esr meter

Koogar (Rupert Hirst) posted an eagle version for the original 5 transistor design here.
https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg407749/#msg407749

I modified this for the latest version (untested / untried). Attaching here for further review by others.
WARNING - this is not tested by me

paronaram · « **Reply #385 on:** February 11, 2023, 07:32:12 pm »

Hello Jay_Diddy_B,

Just finished reading 16 page long post,
Excellent device and very informative read! Thank you for sharing!
Quick question, do you possibly have PCB in Gerber format? All PCB makers accept only Gerber format (at least the once that I know), or if you or anyone else have an extra PCB I would like to have one.
(and of course I will pay for it + shipping - just need to state obvious

)

Thanks again,
Aram.

labjr · « **Reply #386 on:** February 12, 2023, 07:52:58 pm »

Ok, I'm finally tired of my Blue ESR meter. Some things are done better with analog.

I think I want to build one of these. Is the 7 transistor design still a work in progress or is it complete? Is it an improvement over the 5 transistor design or just different?

Thanks

quadtech · « **Reply #387 on:** February 13, 2023, 04:57:54 am »

Quote from: paronaram on February 11, 2023, 07:32:12 pm

Quick question, do you possibly have PCB in Gerber format?

Thanks again,
Aram.

Aram, you can use Eagle to generate gerber files from the attached eagle PCB files (updated from the previous one) in zip format.
I have NOT tested the board yet, but it is a fairly simple circuit and I checked my board multiple times - fairly degree of confidence that it should work.

labjr · « **Reply #388 on:** February 13, 2023, 05:34:59 am »

Quote from: quadtech on February 13, 2023, 04:57:54 am

Aram, you can use Eagle to generate gerber files from the attached eagle PCB files (updated from the previous one) in zip format.
I have NOT tested the board yet, but it is a fairly simple circuit and I checked my board multiple times - fairly degree of confidence that it should work.

What happened to the low drop-out regulator? I'm interested in building a thru-hole version. Anyone interested doing a group buy?

BravoV · « **Reply #389 on:** February 13, 2023, 05:48:57 am »

Quote from: labjr on February 12, 2023, 07:52:58 pm

I think I want to build one of these. Is the 7 transistor design still a work in progress or is it complete? Is it an improvement over the 5 transistor design or just different?

Improvement, it has LED indicator on detecting a bad & shorted capacitor (less than 25 Ohm) which the 5 transistors version does not have.

paronaram · « **Reply #390 on:** February 13, 2023, 02:50:29 pm »

If you are going to order PCB from "quadtech" post, I am in.
Please PM if you need more info.

Thank you,
Aram.

labjr · « **Reply #391 on:** February 13, 2023, 05:09:34 pm »

Quote from: paronaram on February 13, 2023, 02:50:29 pm

If you are going to order PCB from "quadtech" post, I am in.
Please PM if you need more info.

Thank you,
Aram.

I don't believe the thru-hole PCB has been built and tested yet. Also seems to still be using the 7805T regulator. There are plenty of low dropout regulators available. I don't think it needs to be a 1 Amp device?

labjr · « **Reply #392 on:** March 06, 2023, 08:20:10 pm »

Hi Jay_Diddy_B, Thanks for all your help. I sent a PM. Not sure if you received my message?

kallek · « **Reply #393 on:** March 18, 2023, 03:26:54 pm »

Hello everyone! This is my version of this 5 transistor ESR meter.

Thank you Jay_Diddy_B for sharing this design. It seems to work very well!

paronaram · « **Reply #394 on:** March 21, 2023, 04:48:38 am »

Very nice Kallek !

What software do you guys use to scale the printout for the 50uA gauge ?
I purchased 50uA from ebay 44C2 model and all examples from this post are too big or small, so picture need to be resized

Thank you

quadtech · « **Reply #395 on:** March 21, 2023, 06:45:47 am »

Do a google search for "online image scaling", and you will find a bunch of free services.
If you are a Linux user, try "gimp"

Southerner · « **Reply #396 on:** March 21, 2023, 06:55:46 am »

Quote from: quadtech on March 21, 2023, 06:45:47 am

Do a google search for "online image scaling", and you will find a bunch of free services.
If you are a Linux user, try "gimp"

Even if you are a Windows user, try GIMP.

paronaram · « **Reply #397 on:** April 02, 2023, 05:18:14 am »

Thank you for GIMP advice, it worked perfectly. See results in pictures

And I actually complete entire ESR meter, came out very good (I think)
I found 1970's DC mA meter, and repurpose it for this project

Only problem I have is scale calibration, when I short test leads, pointer goes past 0, I understand I need to replace value of R22, 50K will work for this ?
And one more question is there any capacitor ESR reference chart ? I Google it and it's mostly electrostatics from 1uF and up

Thank you Jay_Diddy_B for this awesome Project!!!

labjr · « **Reply #398 on:** April 02, 2023, 01:38:03 pm »

Do you have a pot in series with the meter for Zero Adjust? I just received a nearly identical meter movement and preliminary testing shows that a 10K pot should work fine to zero the meter.

You may need to redo your scale after adding a pot.

paronaram · « **Reply #399 on:** April 02, 2023, 07:03:36 pm »

Thanks labjr.
on my version of "5" Transistor ESR don't have zero adj. pot.
see post from December 30, 2022, 12:04:00 am, I will add 10k in series and see if it fix my issue. I did not do anything with scale, posted picture was resized to feet in this ebay 50mA meter


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Author Topic: 5 Transistor ESR Meter Design (Read 310608 times)

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