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Electronics => Projects, Designs, and Technical Stuff => Topic started by: Jay_Diddy_B on December 14, 2012, 04:07:37 am

Title: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 14, 2012, 04:07:37 am
Hi Forum Members,

There seem to be as many ESR meter designs as people who use them. I have decided to share my ESR meter design with the group.
Strictly speaking this ESR meter does not measure ESR, it measures the impedance of the capacitor under test at 100kHz. For Capacitors larger than a few uF this is approximately equal to the ESR.

ESR meter do not need to be precise, it most instances a bad capacitor will have any ESR many times that of a good one.

When I was kid, radio manufacturers would sell transistor radios based on the number of transistor in them. This is a 5 transistor ESR meter. The only IC that used is a 5V regulator. The circuit should also work directly from 3 or 4 AA batteries without the regulator. The design should work with any general purpose transistors. The diodes in the meter circuit will effect the meter scale. Use small signal Schottky diodes such as 1N5711, common diodes like BAT54 have too much capacitance. OA91 or similar Ge diode should also work.

The maximum voltage on the capacitor under test is 100mV. This allows for in-circuit testing.

The design started with modelling the circuit in LTspice:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37888;image)
The building blocks are labelled.

This is the result of the LTspice modelling, it shows how the meter deflection changes with ESR.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37890;image)

This good because it gives an expanded scale.

From the LTspice model, I made the OrCad schematic:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37892;image)

And then the board layout, I used SMD parts, but thru hole parts could also be used.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37894;image)

The circuit was made from the above design and the components attached:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37896;image)

The meter circuit was hooked up. The meter deflection was measure using some low value resistor. Artwork for a new meter scale was drawn using Corel Draw. The meter scale was printed on Photo paper to be attached to the meter.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37898;image)
The final assembly was completed. Here is a view of the inside of the ESR  meter:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37900;image)

And the Outside:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37902;image)

If you build this, remember to discharge capacitors before using.
Current consumption is 26mA, that is about 25 hours of use.

Regards,

Jay_Diddy_B aka John
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on December 14, 2012, 04:15:57 am
Thanks for sharing !  :-+

Any chance you could share the LTSpice file by attaching it to your 1st post ? Zip it 1st then attach.

Calling Kripton2035 ...   :)
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 14, 2012, 04:39:14 am
I have added the LTspice file to the original message.

To obtain the graph.

Run the LTspice file. The circuit will run 15 times.
This from this SPICE Directive:

.step param R LIST 0.0001 0.1 0.2 0.5 1 2 4 6 8 10 12 14 16 18 20

When the analysis is finished from the VIEW menu 'Spice Error Log'

Then right click in the Error log window.

Click plot .step'ed .meas data

The curve will then be displayed.


Jay_Diddy_B aka John

Title: Re: 5 Transistor ESR Meter Design
Post by: toli on December 14, 2012, 07:42:57 am
Very nice work  :-+

Would have built one myself, but came across this (http://www.ebay.com/itm/181030404166) a couple of weeks ago. For that price I think I'll give that one a try. Some more info can be found here (http://www.diyaudio.com/forums/car-audio/224329-another-ebay-gadget.html).
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 14, 2012, 01:16:41 pm
Toli,

I have had a look at the eBay offering. It looks a lot the AVR Transistor Tester that was started by Markus.

A very detailed description can be found here:

http://www.mikrocontroller.net/attachment/143988/TTester_096k.pdf (http://www.mikrocontroller.net/attachment/143988/TTester_096k.pdf)

It is possible that the software has been expanded to add additional functions. If you search 'markus AVR transistor tester' and look at the images you will find a lot of variations of this design.

It doesn't look like the unit can make in-circuit measurements, but I might be wrong.

You will have to let us know how well this unit works. May be somebody else has one?

In my design, I wanted to see if I could do something useful with a few transistors.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: toli on December 14, 2012, 01:56:45 pm
1. It is similar but of a later version. You can read more in the link I added to diyAudio forum.
2. Says the maximum voltage in the capacitor/ESR measurement range is 300mV, so it should be good for in circuit measurements as well.
Title: Re: 5 Transistor ESR Meter Design
Post by: cwalex on December 15, 2012, 11:49:36 am
That looks awesome! Really professional finish, looks like you used a cnc mill for a lot of it.  :-+
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 15, 2012, 02:57:36 pm
cwalex and the group,

The circuit board and the front panel were made with a LPKF Protomat C60.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37904;image)

Here are some of the capabilities of this awesome machine:



I was extremely lucky to find this, complete with the tools, vacuum and software at a reasonable price.

After milling the board was tinned using MG Chemicals 'Liquid Tin'.

http://www.mgchemicals.com/products/prototyping-and-circuit-repair/prototyping/liquid-tin-421/ (http://www.mgchemicals.com/products/prototyping-and-circuit-repair/prototyping/liquid-tin-421/)


Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: FenderBender on December 16, 2012, 06:35:08 pm
Did you just use some precision resistors for setting the scale? How many did you use?
Title: Re: 5 Transistor ESR Meter Design
Post by: alm on December 16, 2012, 07:17:29 pm
Only five transistors... plus a voltage regulator with more than a dozen transistors ;)
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 16, 2012, 07:18:59 pm
FenderBender & the group,


I would suggest that you get 5 x 1 Ohm and 4 x 10 Ohm  1% resistors

This lets you get the following values:

0.2 Ohm 5 x 1 Ohm in parallel

0.25 Ohm 4 x 1 Ohm in parallel

0.333 Ohm 3 x 1 Ohm in parallel

0.5 Ohm 2 x 1 Ohm in parallel

1 Ohm 1 x 1 Ohm

1.5 Ohm 1 x 1 Ohm + 2 x 1 Ohm in parallel

2 Ohm 2 X 1 Ohm in series

2.5 Ohm 4 x 10 Ohm in parallel

3 Ohm 3 x 1 Ohm in series

4 Ohm 4 x 1 Ohm in series

5 Ohm 2 x 10 Ohm in parallel

Then add 1 Ohm in series to get 6, 7, 8, 9 Ohms

10 Ohms one 10 Ohm resistor


I measured the deflection with the original meter scale. Plotted a graph in Excel and calculated the deflection angles for the marks on the meter.

Keep the leads short especially when measuring the lower values.

Does this make sense ?

After I had finished the ESR meter I checked the calibration with some electrolytic capacitors that had been measured with a HP 4275A LCR (Z) Meter. This LCR meter works at frequencies from 10 kHz to 10 MHz, has a basic accuracy of 0.1% and 5 1/2 Digit display. :-+

Jay Diddy B
Title: Re: 5 Transistor ESR Meter Design
Post by: FenderBender on December 16, 2012, 07:43:31 pm
So you used the 50uA scale since it is a linear scale. You measured the total angle of that scale? And then you did some proportions or something?

Corel Draw makes this easy? I understand how you did the math. Not so sure how I would go about drawing an accurate scale. I have Gimp..not too fluent in it.
Title: Re: 5 Transistor ESR Meter Design
Post by: SeanB on December 16, 2012, 07:55:23 pm
I did a similar thing with mine, just skipped the printing of the scale thing. Used white out to remove the original scale markings, then sat with some resistors and did the same plotting of where the pointer was deflected to, then wrote the values with a Rotring drafting pen. Not the neatest or the most accurate, but does the job.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 16, 2012, 08:22:15 pm
FenderBender & the group,

I measured the meter that I had using digital caliper. In my case the meter was 90o total deflection. Corel Draw defines 0o as vertical. So the angles required are +/- 45o.

Here is an image of the scale under construction:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37886;image)

The construction lines were deleted when the scale was finished.

Corel Draw is probably not the best software to us for this, but it is what I had available.

There is some special software available for doing custom scales. Here is a link to one that get good reviews:

http://tonnesoftware.com/meter2.html (http://tonnesoftware.com/meter2.html)

I believe the MeterBasic, free version, only supports linear scales. I could not justify the $ for one meter.

Jay Diddy B
Title: Re: 5 Transistor ESR Meter Design
Post by: EEVblog on December 21, 2012, 03:42:24 am
Old Skool, nice!  :-+

Dave.
Title: Re: 5 Transistor ESR Meter Design
Post by: KD0CAC John on December 21, 2012, 02:42:18 pm
Both the ARRL [ American Radio Relay league ] books , handbook & antenna book ,  have CDs in then with lots of software , ment for ham radio electronic repair & building .
I would say free , except you have to buy the books :) 
Title: Re: 5 Transistor ESR Meter Design
Post by: HardBoot on December 23, 2012, 06:12:03 am
Really cool gadget, wish I could buy something like that for a few bucks and instead of a meter output to a micro, then a device could monitor it's own caps.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on January 10, 2013, 09:34:38 pm
Hi group,

Has anybody else built this ESR?

Would there be any interest in a thru-hole circuit board design?

Regards,


Jay_Diddy_B

Title: Re: 5 Transistor ESR Meter Design
Post by: redlandman on January 11, 2013, 04:59:05 am
Jay_Diddy_B

I really like the design. I'd like to build it on a single sided board with standard componenets. I've made a few PCB's, but havn't been able to use any of the PCB design tools. I think it would be a great project, as yours has very good low end resolution.

Redlandman
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on November 10, 2013, 03:48:52 pm
Bumping an old thread when looking at various diy esr meter circuits, Jay_Diddy_B, is there any possibilities of modifying the circuit, while still using jelly bean components, but the output is for digital volt meter instead of analog one ? Wishing this will not make the circuit overly complicated compared to the original version.  :-[

The reason I asked is finding a good analog meter is not easy, or at least cheap here in my place, which defies the original purpose that this circuit supposed to be simple, easy to build & cheap ESR meter.  :-//

Hope I'm not asking too much.
Title: Re: 5 Transistor ESR Meter Design
Post by: kripton2035 on November 10, 2013, 04:00:53 pm
I ended up the same way when I build my esr meter years ago.
The go meter didnt exists, I focused on the analog poptronix esr meter
and did not find nor have in a desk the analog meter
so I used a bargraph and a lm3916 and it still works fine !
today I could use more segments (2x10 bargraphs) or the nice 28 segments display I found on ebay.
(http://www.barmeter.com/pic_big/bl28-3005sda04y..jpg)
http://www.barmeter.com/en/viewproduct.asp?ID=184&XiajiID=0 (http://www.barmeter.com/en/viewproduct.asp?ID=184&XiajiID=0)
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on November 10, 2013, 04:08:24 pm
Yeah, maybe for experience EEs or pros which probably have many old unused T&M gadgets that still using analog meter that easily pull one for use, but its quite a hard for enthusiasts like me which usually do not have this kind of old analog gears around.  :'(

But my wish still reasonable I think, especially nowdays a DMM is a electronics noobs must have tool.
Title: Re: 5 Transistor ESR Meter Design
Post by: dannyf on November 10, 2013, 04:20:27 pm
Quote
but the output is for digital volt meter instead of analog one ?

Yeah. I made one, far simpler than the OP's, using logic gates + some diodes, with a voltage read out -> making it an adapter for a digital meter.

As to analog read-out, analog multi-meters are fairly cheap, either in store or on ebay.

The fundamental issue with something like this is that they are NOT ESR meters -> they are ac impedance measurement tools. So you have to run them at high frequency to sufficiently null the impact of the capacitance.
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on November 10, 2013, 04:23:01 pm
Quote
but the output is for digital volt meter instead of analog one ?

Yeah. I made one, far simpler than the OP's, using logic gates + some diodes, with a voltage read out -> making it an adapter for a digital meter.

Schematic ?
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 10, 2013, 06:02:20 pm
Hi,

Before I designed the 5 Transistor ESR meter, I designed and built an ESR meter using a digital panel meter.

The design is unusual in that it uses 10kHz, instead of the more usual 100kHz. By using a synchronous rectifier to measure the in-phase component of the capacitor impedance.

Here is the schematic:

Update - I have corrected the schematic


(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66728;image)

I have attached the schematic in pdf format so that it will be easier to read.

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: dannyf on November 10, 2013, 07:04:19 pm
Quote
Schematic ?

Sure.

V1/R1 is your oscillator (in this case, a 555 running at 120Khz, 40% dc at 5vpp).

R3 is the measurement resistor +  current limiter: pick it to suit your particular oscillator. I am using a 200ma part so I picked R3 to output no more than 150ma current.

R1/C1 is the DUT. With the parameter given, the meter is good down to about 500mohm / 10u. Anything less is going to be difficult to read for a typical multi-meter.

D3 is optional.

The read out point is Vout.

The meter is unique in that Vout goes up monotonically with ESR. You can change that by swapping R3/DUT.

I also built a version with HC132 - It is simpler but the lower current capabilities means higher value R3, limiting the meter to higher value ESRs -> not a big issue.

You can expand the meter's capability by adding an amplifier, or expand its current capabilities.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 10, 2013, 11:34:49 pm
Dannyf and the group,

I modified your LTspice model so that I could get a graph of Vout versus ESR.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66702;image)
These are the results:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66704;image)

The circuit is non-linear below 500 mOhms as you said. This is mainly due to the characteristics of the rectifying diodes. Since the main purpose of these meters is to find capacitors with high ESR values the circuit should be able to do that.

Your circuit also puts more than 0.6V peak on the capacitor under test, so if there are any diodes in parallel with the capacitor under test, the range is limited to about 8 ohms. Again this is not really a concern, because it is probably a bad capacitor.


Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Stonent on November 11, 2013, 08:52:43 am
I'm loving the Allen Bradley 10K pot on it. It adds a bit of industial-ness to it.

A-B
Quality
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on November 11, 2013, 03:43:51 pm
Before I designed the 5 Transistor ESR meter, I designed and built an ESR meter using a digital panel meter.

The design is unusual in that it uses 10kHz, instead of the more usual 100kHz. By using a synchronous rectifier to measure the in-phase component of the capacitor impedance.

Jay_Diddy_B, thanks, that looks interesting.

Now, as usual, incoming bombardments of noob questions  >:D :

- What is so special about that "synchronous rectifier" method compared to others common "cheap DIY" ESR measurement techniques ?
- Why 10 KHz ? How about other frequency like 100 KHz ? or lower ?
- Any pre-adjustments or tunings required when finished building it ?


Quote
Schematic ?

Sure.

dannyf, thanks for the circuit, this going to take times to digest here, remember, its an EEE here, not an EE.  ;D

But as Jay_Diddy_B pointed out, below 500 mOhm limitation will be quite difficult when dealing with ultra low ESR cap like those polymer type isn't it ? Sometimes it goes down to teens of mili Ohm.

About adding an amp for increasing it's current capabilities, mind elaborate further why we need that ? For bigger cap ?
Title: Re: 5 Transistor ESR Meter Design
Post by: dannyf on November 11, 2013, 04:17:14 pm
Increasing the oscillator's current capabilities allows you to use a smaller measurement resistor, thus dropping proportionally more voltage on the dut -> higher reading out of the rectifiers. The basic principle of the circuit is to run at high enough frequencies so that only the ESR element of the capacitor has any impact on the output.

One simple but dumb way to increase the oscillator's current output is to use a buffer, like a pnp/npn pair configured as follower, or some mosfet gate drivers.

Alternatively, you amplify the signal out of the dut. An opamp will do - but in this particularly configuration, the signal will be very close to ground so you need to look for an opamp with pnp input stage.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 12, 2013, 03:05:30 am
Before I designed the 5 Transistor ESR meter, I designed and built an ESR meter using a digital panel meter.

The design is unusual in that it uses 10kHz, instead of the more usual 100kHz. By using a synchronous rectifier to measure the in-phase component of the capacitor impedance.

Jay_Diddy_B, thanks, that looks interesting.

Now, as usual, incoming bombardments of noob questions  >:D :

- What is so special about that "synchronous rectifier" method compared to others common "cheap DIY" ESR measurement techniques ?
- Why 10 KHz ? How about other frequency like 100 KHz ? or lower ?
- Any pre-adjustments or tunings required when finished building it ?

This screen shot from the scope will help answer the questions.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66832;image)

The upper trace is the output of the 10kHz oscillator.
The second trace is the output of the 10kHz bandpass filter, a reasonably nice sine wave.
The next trace is the output of the differential amplifier, that is the voltage across the capacitor under test.
The lower trace is the output of the synchronous detector. The imaginary components cancel. The in phase component, the resistive part is averaged and then displayed on the meter.

In this scope shot I am measuring a 4.7uF capacitor with an ESR of 1.2 Ohms. impedance  Z= 1.2 -3.3j ohms,    |Z|= 3.5 ohms.
The ESR meter correctly reads 1.2 Ohms.

10KHz was chosen as a compromise. 100kHz is the traditional frequency used for ESR measurements. At a 100KHz I would have needed some faster op-amps and a better analog switch.

I have checked this circuit against an HP 4274A LCR (Z) meter and it gives very accurate results for the cost.

There are several weaknesses in this design:

1) The amplitude of the square wave is dependant on how close the op-amp can swing to the rail.

2) The amplitude of the sine wave depends on being in the center of the band pass filter.

3) I tweaked the value of the R23 to obtain the calibration.

This circuit has a nice linear response. It is a true ESR meter, it is not an impedance meter. It use as nice low voltage test signal to allow in circuit measurements. It will work with a DMM, but you have to multiply the voltage read by 10x to get ohms.

Jay_Diddy_B



Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on November 12, 2013, 04:13:41 am
Thanks for the signal's scope shot, that helps me to further getting a grip on this circuit.  :-+

Btw, I have to be honest with you, that most of my questions are from an enthusiast level perspective, which emphasizing more at practicality point of view. Its not I'm lazy to learn in depth on how it works, its just it will take much longer time for me to catch up since without any strong foundation of electronics knowledge, and experiences like you EE or pro do. While the main interest is still on building it, hope you can bear with me here.  :P

More ..   >:D

10KHz was chosen as a compromise. 100kHz is the traditional frequency used for ESR measurements. At a 100KHz I would have needed some faster op-amps and a better analog switch.
How fast op-amp needed at 100 KHz ? Any example of popular op-amp ? Non the exotic one if possible, please.


There are several weaknesses in this design:

1) The amplitude of the square wave is dependant on how close the op-amp can swing to the rail.
2) The amplitude of the sine wave depends on being in the center of the band pass filter.
3) I tweaked the value of the R23 to obtain the calibration.
So I'm assuming from above points, this circuit has a fixed test frequency ?


This circuit has a nice linear response. It is a true ESR meter, it is not an impedance meter. It use as nice low voltage test signal to allow in circuit measurements. It will work with a DMM, but you have to multiply the voltage read by 10x to get ohms.
Will a cheap say like common low offset op-amp, set up as 10X gain connected at TP7 enough for that ? cmiiw


Have no intention to derail the discussion from this fine circuit, just curious about another diy esr meter circuit that output to DMM -> here (http://archive.siliconchip.com.au/cms/A_103805/article.html) (scroll down abit at the bottom), or link to the schematic -> here (http://archive.siliconchip.com.au/static/images/articles/i1038/103805_2mg.jpg) for better view.
Does it use the same/similar synchronous rectification method ? The reason I bring this out because I see it uses switches to switch the test signal back & forth like yours.  :-//
Title: Re: 5 Transistor ESR Meter Design
Post by: Stonent on November 12, 2013, 04:21:33 am
Thanks for the signal's scope shot, that helps me to further getting a grip on this circuit.  :-+

Btw, I have to be honest with you, that most of my questions are from an enthusiast level perspective, which emphasizing more at practicality point of view. Its not I'm lazy to learn in depth on how it works, its just it will take much longer time for me to catch up since without any strong foundation of electronics knowledge, and experiences like you EE or pro do. While the main interest is still on building it, hope you can bear with me here.  :P

More ..   >:D

10KHz was chosen as a compromise. 100kHz is the traditional frequency used for ESR measurements. At a 100KHz I would have needed some faster op-amps and a better analog switch.
How fast op-amp needed at 100 KHz ? Any example of popular op-amp ? Non the exotic one if possible, please.


There are several weaknesses in this design:

1) The amplitude of the square wave is dependant on how close the op-amp can swing to the rail.
2) The amplitude of the sine wave depends on being in the center of the band pass filter.
3) I tweaked the value of the R23 to obtain the calibration.
So I'm assuming from above points, this circuit has a fixed test frequency ?


This circuit has a nice linear response. It is a true ESR meter, it is not an impedance meter. It use as nice low voltage test signal to allow in circuit measurements. It will work with a DMM, but you have to multiply the voltage read by 10x to get ohms.
Will a cheap say like common low offset op-amp, set up as 10X gain connected at TP7 enough for that ? cmiiw


Have no intention to derail the discussion from this fine circuit, just curious about another diy esr meter circuit that output to DMM -> here (http://archive.siliconchip.com.au/cms/A_103805/article.html) (scroll down abit at the bottom), or link to the schematic -> here (http://archive.siliconchip.com.au/static/images/articles/i1038/103805_2mg.jpg) for better view.
Does it use the same/similar synchronous rectification method ? The reason I bring this out because I see it uses switches to switch the test signal back & forth like yours.  :-//

Sounds like the same idea that Dave had with the uCurrent.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 13, 2013, 03:01:17 am

How fast op-amp needed at 100 KHz ? Any example of popular op-amp ? Non the exotic one if possible, please.


Will a cheap say like common low offset op-amp, set up as 10X gain connected at TP7 enough for that ? cmiiw


Here is a LTspice model for a 100 kHz version. This uses LTC6244HV dual op-amps. These have 50MHz GBW and 35V/us Slew rate.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66920;image)

I have attached the LTspice model. You can experiment with the LTspice model.

I really think that there is little advantage over using 100 kHz instead of 10 kHz.

A 10x simple op-amp could be used for 10x correction, but unless you have a 24 rail, you will limit the maximum resistance that can be read.

Have no intention to derail the discussion from this fine circuit, just curious about another diy esr meter circuit that output to DMM -> here (http://archive.siliconchip.com.au/cms/A_103805/article.html) (scroll down abit at the bottom), or link to the schematic -> here (http://archive.siliconchip.com.au/static/images/articles/i1038/103805_2mg.jpg) for better view.
Does it use the same/similar synchronous rectification method ? The reason I bring this out because I see it uses switches to switch the test signal back & forth like yours.  :-//

Yes, the use of the analog switch to form a synchronous detector is similar. It applies a square wave current to the capacitor. In this circuit there is a trade off using analog switches at low signal levels and then dc amplification versus amplifying the ac signal and then using the analog switches.
It would be interesting to build a model of this circuit.

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 13, 2013, 03:58:51 am
Hi,

This is the ESR meter mention by BravoV:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66926;image)

Here is a very simplified and idealized model for the Silicon Chip ESR meter:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66923;image)


The test results from LTspice:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66928;image)

I have attached the model if people want to play with it.

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: dannyf on November 13, 2013, 12:17:15 pm
Quote
This is the ESR meter mention by BravoV:

Could you build a flip/flop from the spare gates? Or to build an oscillator from the spare flip/flop. Saving one IC.
Title: Re: 5 Transistor ESR Meter Design
Post by: kripton2035 on November 13, 2013, 03:34:11 pm
you cn use a single gate inverter like this one from TI : http://www.ti.com/product/sn74auc1g06 (http://www.ti.com/product/sn74auc1g06)
this does not save an ic but saves space and eliminates useless gates.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 13, 2013, 10:26:36 pm
Hi,
Unless, you redesign the circuit to work at lower voltages you can not use the SN74AUCxx series parts, they are low voltage parts.

The silicon chip design has the logic powered from -5 to +5V. The design use 4000 series CMOS.

To make a divide by 2, D-type flip-flop, I think that you need 4 two input gates. I can not see a way to reduce the IC count.

Jay_Diddy_B
 
Title: Re: 5 Transistor ESR Meter Design
Post by: AndersAnd on November 13, 2013, 11:33:20 pm
R1/C1 is the DUT.
R2/C1  :-/O
Title: Re: 5 Transistor ESR Meter Design
Post by: AndersAnd on November 13, 2013, 11:39:26 pm
Quote
This is the ESR meter mention by BravoV:

Could you build a flip/flop from the spare gates? Or to build an oscillator from the spare flip/flop. Saving one IC.
Speaking of saving components. Danny F in your design you could replace the two BAT54 with one BAT54S (two BAT54 in sereies):

(http://circuits.datasheetdir.com/75/VISHAY-BAT54-pinout.jpg)

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66675;image)
Title: Re: 5 Transistor ESR Meter Design
Post by: dannyf on November 13, 2013, 11:51:00 pm
Quote
I can not see a way to reduce the IC count.

Using two ICs of one type is also a move in the right direction.
Title: Re: 5 Transistor ESR Meter Design
Post by: dannyf on November 14, 2013, 12:05:48 am
Another way would be to use a mcu to output the two signals.
Title: Re: 5 Transistor ESR Meter Design
Post by: AndersAnd on November 14, 2013, 01:13:38 am
Another way to reduce component count is to replace the four 1N4004 diodes with a bridge rectifier. The bridge rectifier will then be hooked up in a unusual way with both the + and - outputs connected to GND.

At the top I drew a part of the original schematic and at the bottom a the modified schematic with the bridge rectifier.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=67053;image)

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66926;image)
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on November 14, 2013, 04:09:23 am
Here is a LTspice model for a 100 kHz version. This uses LTC6244HV dual op-amps. These have 50MHz GBW and 35V/us Slew rate.

Whats the minimal GBW & slew rate for this to work ?


I really think that there is little advantage over using 100 kHz instead of 10 kHz.

Ok, I keep hearing this, is there any examples where 100 KHz has the advantage over 10 KHz ?


A 10x simple op-amp could be used for 10x correction, but unless you have a 24 rail, you will limit the maximum resistance that can be read.

I think max resistance at 10 Ohm should be good enough ? Especially majority uses of this kind of diy esr kit will be sorting out old and bad caps. Or maybe checking if they've been conned by a shady seller after buying those cheap ultra low esr polymer caps.  >:D


Yes, the use of the analog switch to form a synchronous detector is similar. It applies a square wave current to the capacitor. In this circuit there is a trade off using analog switches at low signal levels and then dc amplification versus amplifying the ac signal and then using the analog switches.
It would be interesting to build a model of this circuit.
The test results from LTspice:
I'm still lost in understanding that circuit, what this test result is telling if you don't mind explain a bit ?  :P
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 14, 2013, 05:02:57 am
I really think that there is little advantage over using 100 kHz instead of 10 kHz.

Ok, I keep hearing this, is there any examples where 100 KHz has the advantage over 10 KHz ?

Using a 100kHz has advantages if you design an ESR meter that measures the impedance of the capacitor instead of the ESR. This determines how effective the meters work for low value capacitors.
If the meter is able to measure the in-phase component of the impedance, which is the ESR, then the frequency does not need to be as high.
General speaking you can tell by looking at the rectifier. If the rectifier use analog switches driven by the source, then the meter is measuring the ESR. If diodes are used then circuit is measuring impedance.

I'm still lost in understanding that circuit, what this test result is telling if you don't mind explain a bit ?  :P

The test result has the value of the test resistor on the X axis and the output voltage or meter reading on the Y axis. What you are looking for is a straight line that goes through 0,0. This tell you that the meter is linear and has the capability to measure low values of ESR accurately. You can also change the value of the capacitor in the simulation. A good ESR meter will be able to measure the ESR of a low value capacitor correctly.

In the 10 kHz digital ESR meter that I post I can correctly measure a 4.7uF capacitor with an ESR of 1.2 Ohms. This is good enough for me.

Here is a 4.7uF 85C capacitor in the homemade 10kHz ESR meter:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=67083;image)

Here is the same capacitor in an HP 4274A Multi-Frequency LCR meter (5 1/2 Digits 0.1% , around $1000 to $1500 for a used one, the 16047D Test Fixture is worth about $250.00):

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=67085;image)


Close enough for me  :-+

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on November 14, 2013, 06:27:07 am
Using a 100kHz has advantages if you design an ESR meter that measures the impedance of the capacitor instead of the ESR. This determines how effective the meters work for low value capacitors.
If the meter is able to measure the in-phase component of the impedance, which is the ESR, then the frequency does not need to be as high.

Btw, here as an example I'm talking about an enthusiast that is trying to fix a switching power supply, and don't have any other tools like a scope to watch the ripple. Only cheap DMM and the cheap diy esr meter, I used to be like that.  :'(

Now, questions from that "enthusiast's" perspective, since I believe this represents most of the cases in hobbyist world. I'm troubleshooting a power switcher and suspecting the caps at the secondary side are bad. Looking at the datasheet the cap's ESR specification measured at 100Khz say 20 mili Ohm, now, if I'm going to verify those cap whether they're still in spec, by using again, a cheap DIY ESR meter, will 10Khz signal is good enough ?


The test result has the value of the test resistor on the X axis and the output voltage or meter reading on the Y axis. What you are looking for is a straight line that goes through 0,0. This tell you that the meter is linear and has the capability to measure low values of ESR accurately. You can also change the value of the capacitor in the simulation. A good ESR meter will be able to measure the ESR of a low value capacitor correctly.

Great learning here, thank you !  :-+


In the 10 kHz digital ESR meter that I post I can correctly measure a 4.7uF capacitor with an ESR of 1.2 Ohms. This is good enough for me.

As above example, say you yourself are verifying a new purchased of a batch of expensive OS-CON ultra low esr caps that has just few teens of mili Ohms, how are you going to do that ? I'm really interested to hear this.


Here is the same capacitor in an HP 4274A Multi-Frequency LCR meter (5 1/2 Digits 0.1% , around $1000 to $1500 for a used one, the 16047D Test Fixture is worth about $250.00):

Sigh ... I rejected an offer while ago on this exact piece of nice gear with out the test fixture though, for about < $200 locally here when I was totally a noob.  :'(
Title: Re: 5 Transistor ESR Meter Design
Post by: kripton2035 on November 14, 2013, 07:06:19 am
if you dont have an enought precise esr meter, just change the suspected capacitor with an almost the same one
the secondaryside capacitors are not very special.
I always have some high voltages capacitors (400v 10µ 22µ or 47µF) on hand to test the high side capacitor easily
I have a small analog diy esr meter (the poptronix modified one) and it has detected a big quantity of bad capacitors, but sometimes it doent detect anything. example : a motherboard plane with 20 capacitors in parallel : you have to desoldier all of them ( and it's not easy at all) and test them but your diy meter is not enought precise to detect clearly in the ten m? range ...
Title: Re: 5 Transistor ESR Meter Design
Post by: notsob on November 14, 2013, 08:51:15 am
here's one with an analog display

http://www.users.on.net/~endsodds/esr.htm (http://www.users.on.net/~endsodds/esr.htm)
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 14, 2013, 01:19:11 pm
Hi Notsob and the group,

Here is a quick analysis of the VK5JST ESR meter. The operation of this meter is very similar to the 5 transistor design at the start of this thread. It place the rectifier inside the feedback loop of an op-amp. This type of  circuit has the advantage that the signals are larger for small ESRs than they are for higher values.

Model:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=67103;image)

Meter Deflection versus ESR:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=67105;image)

There makes for a nice non-linear scale on the meter.

I have attached the LTspice model for people who want to experiment.

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on November 15, 2013, 01:50:23 am
Here is a quick analysis of the VK5JST ESR meter. The operation of this meter is very similar to the 5 transistor design at the start of this thread. It place the rectifier inside the feedback loop of an op-amp. This type of  circuit has the advantage that the signals are larger for small ESRs than they are for higher values.

Off topic, in above simulation, which parts represent the analog meter ?
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 15, 2013, 01:56:42 am
BravoV and the group,

R18 represents the analog meter. So the current in R18 is proportional to the meter deflection. The simulation does not include the zero pot. The zero pot would be used to set the meter current to 1mA with a short on the input.

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on November 15, 2013, 02:19:26 am
Thanks, now I'm writing this into my notebook, in spice simulation ... resistor = analog meter.  :-+
Title: Re: 5 Transistor ESR Meter Design
Post by: AndersAnd on November 15, 2013, 08:56:31 am
Off topic, in above simulation, which parts represent the analog meter ?
R18

You can find info about VK5JST's ESR meter here http://www.users.on.net/~endsodds/esr.htm (http://www.users.on.net/~endsodds/esr.htm)

Direct link to the PDF schematic: http://www.users.on.net/~endsodds/ESRCircuit.pdf (http://www.users.on.net/~endsodds/ESRCircuit.pdf)
Title: Re: 5 Transistor ESR Meter Design
Post by: dannyf on November 15, 2013, 12:19:57 pm
You could change the last stage slightly so the output is a voltage signal - good for both analog and digital multi-meters.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 15, 2013, 01:14:23 pm
DannyF and the group,

To answer your question.

Nearly all of the ESR meters designed for analog meters have a non-linear response. My 5 transistor ESR meter at the start of the thread had a response like this:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37890;image)

This results in a meter scale like this:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37898;image)

This non-linear scale is  actually desirable on an analog meter, because it expands the lower value readings over a large section of the meter scale.

The digital meters require an output which is linear and proportional to the ESR.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=66928;image)



It would be quite challenging to take the non-linear output from an analog style ESR meter and convert it into a linear scale for a digital meter.

So there are really two kinds of ESR meter circuits.

I hope that this answers your question.

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: dannyf on November 15, 2013, 01:31:37 pm
Quote
a non-linear response.

It is not about linearity. It is about having a current output vs. a voltage output.
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on November 15, 2013, 03:10:55 pm
You could change the last stage slightly so the output is a voltage signal - good for both analog and digital multi-meters.

Post how and the circuit, please.

Hope it will not be too complicated to build or need exotic hard to find components.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 31, 2013, 05:41:48 pm
Hi group,

 A couple of people have asked me to clarify the connections to the potentiometer and the meter. So here is a revised schematic that shows these connections:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=74058;image)


Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: cellularmitosis on December 31, 2013, 09:30:23 pm
What a cool project!

Not to hijack the thread, but I wanted to mention that a while back I whipped up a quick python script for generating analog gauge faces like that:

http://jason.pepas.com/wiki/index.php?title=AsiaEngineerGauges (http://jason.pepas.com/wiki/index.php?title=AsiaEngineerGauges)

http://jason.pepas.com/wiki/images/5/58/Asiaengineer-0.5-signorm.png (http://jason.pepas.com/wiki/images/5/58/Asiaengineer-0.5-signorm.png)

I suppose I should put it up on github!


Title: Re: 5 Transistor ESR Meter Design
Post by: koogar on March 17, 2014, 03:16:01 pm
Hi group,

Has anybody else built this ESR?

Would there be any interest in a thru-hole circuit board design?

Regards,


Jay_Diddy_B

Hi Guys

I have designed a through hole version of the 5 transistor ESR off  Jay's  schematic below

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=74058;image)


What could I substitute for the ES1J SMD diodes,  D1 & D2 in through hole ?
Also what are the common alternatives for D3 & D4 ?

I will post all the files after I have updated the Schematic and PCB layout.

Cheers

Rupert
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on March 17, 2014, 07:59:00 pm
does it make sense to couple a sub circuit that "eats" this signal and "anti-logs" it (or log it?)? so that it spews something linear?
Like this ?  ;)

Click -> ESR Meter Adapter Design and Construction (https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/) , came from same designer as this one by our great contributor Jay_Diddy_B.  :clap:
Title: Re: 5 Transistor ESR Meter Design
Post by: koogar on March 17, 2014, 10:16:02 pm
Hey Guys

Here are the PCB files for a through hole version .

(http://homepage.ntlworld.com/ruperthirst/Forum%20Files/runawaybrainz.blogspot/ESR%20Project/5%20Transistor%20ESR%20Through%20Hole.png)

(http://homepage.ntlworld.com/ruperthirst/Forum%20Files/runawaybrainz.blogspot/ESR%20Project/5%20Transistor%20ESR%20Through%20Hole%20SCH.png)


Eagle PCB Files Attached

Cheers

Rupert
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 17, 2014, 10:46:15 pm
Hi,

Rupert,
That is a great job you have done with the design, converting it to thru-hole  :clap:


The ES1J diodes can be replaced by 1N4001, 1N4002 etc or 1N4935. These diodes take a beating if you connect a charged capacitor to the terminals.

D3 and D4 are critical, the 1N5711 will be fine. You need low capacitance small-signal Schotky diodes.


You want a panel mounted potentiometer for R23. You have to zero the meter to adjust for the lead resistance.

How are you going to make the board?

I will be happy to answer any questions that you might have.

Good luck !!

Jay_Diddy_B

Title: Re: 5 Transistor ESR Meter Design
Post by: koogar on March 17, 2014, 11:30:05 pm
Thanks for the advice and feedback Jay :)

The pot was only really on the PCB for testing  purposes.

what value would you suggest for R24 in series with the meter ?

All my panel meters seem to be 100uA,  what modifications do you suggest to drive it full scale ?
I will be etching the PCB.

PS. thanks for sharing your design, I will keep the thread updated

Thanks

Rupert


Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 18, 2014, 12:47:43 pm
Rupert and the group,

If you have a 100uA meter, the total resistance, meter + resistor plus + (pot resistance / 2) should be equal to about 7.5 k Ohms.

Jay_Diddy_B

Title: Re: 5 Transistor ESR Meter Design
Post by: 1jonnyz on March 18, 2014, 01:17:53 pm
I wonder how difficult would this be to build on a stripboard?  It seems like I would run out of room, given the size of my box, which is 6" x 3 1/2".
Title: Re: 5 Transistor ESR Meter Design
Post by: zaoka on March 18, 2014, 01:50:13 pm
So what do I modify to increase the range of up to 50ohm without loosing 20% of the scale for 0-1 range?
  :-//

Also to use 1mA meter.

Plsss :)
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 18, 2014, 03:23:30 pm
Hi group,

The deflection of the meter versus ESR comes from the properties of the unbalanced bridge circuit used in the design. You can adjust the resistor values in the lower legs of the bridge to bend the meter response.

This is an LTspice model that illustrates the effect of changing the resistor value. I have normalized the models to show 0-100% deflection.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=85651;image)

These are the results for 1,3 and 10 Ohms:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=85653;image)

3 Ohms was chosen the design to give the best scale on the meter, for the majority of applications.

Most electrolytic capacitors have an ESR less than 20 Ohms, if they are good.

Note: this model does not include the non-linearity introduced by the 1N5711 diodes.

It is not easy to adapt the circuit for a 1mA meter.



Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: jim17 on March 18, 2014, 04:18:45 pm
Hi Jay_Diddy_B,

I'm trying to simulate your circuit trhough ltspice, how do you do the plot ESR vs voltage ?


Thanks.
Title: Re: 5 Transistor ESR Meter Design
Post by: zaoka on March 18, 2014, 05:13:11 pm

Most electrolytic capacitors have an ESR less than 20 Ohms, if they are good.



If you test capacitors lower than 10uF range higher than 20R is needed, at least according to Sencore ESR troubleshooting sheet with min-max ESR values.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 18, 2014, 08:06:36 pm
Hi,

Jim17 asked:

Hi Jay_Diddy_B,

I'm trying to simulate your circuit trhough ltspice, how do you do the plot ESR vs voltage ?


Thanks.

To obtain the graph.

Run the LTspice file. The circuit will run 15 times.
This from this SPICE Directive:

.step param R LIST 0.0001 0.1 0.2 0.5 1 2 4 6 8 10 12 14 16 18 20

When the analysis is finished from the VIEW menu 'Spice Error Log'

Then right click in the Error log window.

Click plot .step'ed .meas data

The curve will then be displayed.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: jim17 on March 19, 2014, 02:15:05 pm
Hi Jay_Diddy_B,

Thanks for the response, I've done the steps and it worked !

Watching the different circuits you've done, I realise LTspice is a powerful tool to design analog circuits.

Keep the great job in this forum !
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on March 19, 2014, 02:21:31 pm
His LTSpice kungfu is probably one of the best around here.  :box:
Title: Re: 5 Transistor ESR Meter Design
Post by: w2aew on March 23, 2014, 12:41:50 am
does it make sense to couple a sub circuit that "eats" this signal and "anti-logs" it (or log it?)? so that it spews something linear?
Like this ?  ;)

Click -> ESR Meter Adapter Design and Construction (https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/) , came from same designer as this one by our great contributor Jay_Diddy_B.  :clap:

ah yes  :-+

i can understand that a charge is generated (oscillator), dumped into DUT, then it gets picked up and measured. but specifically, i dont understand how do you know 1ohm is really 1 ohm ESR. in theory i can understand the reactance calculation, but in most ESR meters am i right to say, the correct way is to measure its potential after it gets a "known" test charge? or there is more theory i am missing?

i try to simulate it here https://www.eevblog.com/forum/beginners/esr-frontend (https://www.eevblog.com/forum/beginners/esr-frontend)   |O :-DD ... did i just confuse myself?

The principle with most ESR meters like this is to apply a test signal at a frequency that is high enough for the capacitive reactance to be well under 1 ohm. Thus, any voltage appearing across the capacitor is due to the ESR alone.
Title: Re: 5 Transistor ESR Meter Design
Post by: JoeO on March 25, 2014, 11:52:08 am
Hey Guys

Here are the PCB files for a through hole version .


Eagle PCB Files Attached

Cheers

Rupert

I have downloaded and attempted to extract the files on 2 different systems.  They both indicate that the zip file is empty.
Title: Re: 5 Transistor ESR Meter Design
Post by: koogar on March 25, 2014, 01:37:52 pm
Try now JoeO

I compressed it as a ZIP, the files are also updated.

I had to rename the extention as ZIP as the forum doesnt allow RAR files. This works fine with WinRAR but windows extracter may not like it.

Thanks
Rupert
Hey Guys

Here are the PCB files for a through hole version .


Eagle PCB Files Attached

Cheers

Rupert

I have downloaded and attempted to extract the files on 2 different systems.  They both indicate that the zip file is empty.
Title: Re: 5 Transistor ESR Meter Design
Post by: koogar on March 25, 2014, 01:44:42 pm
Hi Guys,

I had some time over the weekend to etch my through hole PCB design, and calibrate a scale.
The more observant may notice the Easter Egg on the scale ;) ( Mr Jones may have a chuckle)

(http://homepage.ntlworld.com/ruperthirst/Forum%20Files/runawaybrainz.blogspot/ESR%20Project/IMG_20140325_130310%20(Medium).jpg)

Looks as if it works great, thanks Jay for sharing :)

Now I just need to make an enclosure.

PS. The missing 2.2uf caps on the picture are SMD mounted, underneath the PCB


Thanks

Rupert
Title: Re: 5 Transistor ESR Meter Design
Post by: akis on March 25, 2014, 02:00:18 pm
In terms of compactness and size for a through hole your design beats the pants off whatever I can make. Can you please tell me how you designed it?
Title: Re: 5 Transistor ESR Meter Design
Post by: JoeO on March 25, 2014, 02:04:31 pm
Try now JoeO

I compressed it as a ZIP, the files are also updated.

I had to rename the extention as ZIP as the forum doesnt allow RAR files. This works fine with WinRAR but windows extracter may not like it.

Thanks
Rupert
THANK YOU!  I can unzip it now.
JoeO
Title: Re: 5 Transistor ESR Meter Design
Post by: koogar on March 25, 2014, 02:19:38 pm

In terms of compactness and size for a through hole your design beats the pants off whatever I can make. Can you please tell me how you designed it?

About a day laying it out in Eagle PCB based off Jays's Schematic :)

I was pretty happy with the layout size wise, but I am sure there are plenty in here that would think I wasted a lot of PCB material ;)

I may have another go at it using smaller resistors, to get it down to 50 x 50mm  for iTeads cheap PCB service.

I also made the meter scale in Eagle PCB, after all it is CAD.

Cheers

Rupert
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 25, 2014, 02:32:26 pm
Hi group, :clap:

It is nice to see other people successfully building the meter  :clap:

I had designed a thru-hole version of the board. I never built the thru-hole version.

This is my design:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=86493;image)

The dimensions are 3.00 x 1.75 inches (75 x 44mm)

The 7805 can be replaced by the 78L05, this saves a lot of space. This layout is single sided. If you use itead you can use both sides and vias.


Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: koogar on March 25, 2014, 02:39:07 pm
Hi group, :clap:

It is nice to see other people successfully building the meter  :clap:

I had designed a thru-hole version of the board. I never built the thru-hole version.

The dimensions are 3.00 x 1.75 inches (75 x 44mm)

The 7805 can be replaced by the 78L05, this saves a lot of space. This layout is single sided. If you use itead you can use both sides and vias.


Regards,

Jay_Diddy_B

WOW! that's weird, Jay_Diddy_B

your dimensions are exactly the same as the PCB I designed give or take a  mm
Title: Re: 5 Transistor ESR Meter Design
Post by: w2aew on March 25, 2014, 03:19:45 pm
Hi Guys,

I had some time over the weekend to etch my through hole PCB design, and calibrate a scale.
The more observant may notice the Easter Egg on the scale ;) ( Mr Jones may have a chuckle)

(http://homepage.ntlworld.com/ruperthirst/Forum%20Files/runawaybrainz.blogspot/ESR%20Project/IMG_20140325_130310%20(Medium).jpg)

Looks as if it works great, thanks Jay for sharing :)

Now I just need to make an enclosure.

PS. The missing 2.2uf caps on the picture are SMD mounted, underneath the PCB


Thanks

Rupert

Love the Easter egg(s) on the meter scale.  Thanks Doc!
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on March 25, 2014, 03:43:50 pm
Rupert, aesthetically, that is one lovely pcb work you've done there, thanks for sharing.   :clap:

Also really love the idea using a printed paper for the silkscreen for a single sided through hole electronic project, definitely will adopt this idea for my next one.  :-+
Title: Re: 5 Transistor ESR Meter Design
Post by: koogar on March 26, 2014, 10:40:44 pm
Looks like we made it on to Dangerous Prototypes :P

http://dangerousprototypes.com/2014/03/26/dr-browns-capacitor-esr-tester/ (http://dangerousprototypes.com/2014/03/26/dr-browns-capacitor-esr-tester/)

I was also thinking something like these student lab meters would make an excellent meter/enclosure, with the correct meter sensitivity




Cheers

Rupert
Title: Re: 5 Transistor ESR Meter Design
Post by: at2marty on April 04, 2014, 04:54:17 pm
Just a quick question.

I've been researching a lot of different DIY ESR builds, and have decided to give this one a try.  My question is, would  2N2222 work in place of the 2N3904 transistors?  From what I can tell from the data sheets, they seem pretty similar.  The reason that I ask is I have a ton of 2N2222's sitting in my parts box.
Title: Re: 5 Transistor ESR Meter Design
Post by: dannyf on April 04, 2014, 05:39:24 pm
Quote
I had some time over the weekend to etch my through hole PCB design, and calibrate a scale.

Nicely done.

Here is one way you can tell if the meter is accurate.

1) pick a cap (any cap), take a ESR reading off your meter;
2) put a known resistor (1ohm or 0.47ohm for example) in serial with the cap used in 1), take another ESR reading off your meter;
3) the difference between the two readings should be the value of that known resistor.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on April 04, 2014, 09:21:29 pm
Just a quick question.

I've been researching a lot of different DIY ESR builds, and have decided to give this one a try.  My question is, would  2N2222 work in place of the 2N3904 transistors?  From what I can tell from the data sheets, they seem pretty similar.  The reason that I ask is I have a ton of 2N2222's sitting in my parts box.

Yes, you can use 2N2222, BC548 will work for European constructors, for the npn transistors.

2N2907 or BC558 etc. will work for the PNP transistor.

Regards,

Jay_Diddy_B

Title: Re: 5 Transistor ESR Meter Design
Post by: at2marty on April 04, 2014, 10:47:12 pm
Just a quick question.

I've been researching a lot of different DIY ESR builds, and have decided to give this one a try.  My question is, would  2N2222 work in place of the 2N3904 transistors?  From what I can tell from the data sheets, they seem pretty similar.  The reason that I ask is I have a ton of 2N2222's sitting in my parts box.

Yes, you can use 2N2222, BC548 will work for European constructors, for the npn transistors.

2N2907 or BC558 etc. will work for the PNP transistor.

Regards,

Jay_Diddy_B

Thank you very much for the answer Jay_Diddy_B!  I have been re-drawing the circuit with the parts that I plan to use.  I haven't deviated much except for the power supply portion (and the NPN transistors).  I am planning on using a L4931-50 regulator since a) I have some on hand and b) it has a bit smaller form factor.  I believe that I found a suitable meter so I can work out what resistor value I need for the final stage.

I plan on sharing my design so that others can try it out.  I would really like the 4 wire option to be included in this project.  I need to do some more research to determine what I need to add in order to accomplish this.  Rest assured, you and R. Hirst will be given the credit that you deserve.  That's part of the beauty of Open Source!  Thank you so much for all that you contribute.   :-+

I really like your other design, and I would attempt it, but my old eyes and shaky hands scare me when it comes to SMD stuff.  The way that you presented the design and showed the Spice models is truly impressive.  Please keep this up because us old geeks really dig this stuff.   :-+
Title: Re: 5 Transistor ESR Meter Design
Post by: koogar on April 05, 2014, 01:43:42 pm
Good luck with your build at2marty :P

I just finished the my enclosure.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=88062)

As usual the enclosure becomes the hardest part of the project!




Title: Re: 5 Transistor ESR Meter Design
Post by: at2marty on April 06, 2014, 11:15:55 am
Very nice koogar!  :-+
Title: Re: 5 Transistor ESR Meter Design
Post by: XombyCraft on August 04, 2014, 01:45:57 am
Gahhhh... why is it so hard to find 1n5711's in my random e-waste board pile?  How terrible would it be to use 1n4148?
Title: Re: 5 Transistor ESR Meter Design
Post by: XombyCraft on October 03, 2014, 07:00:36 pm
Hi group,

The deflection of the meter versus ESR comes from the properties of the unbalanced bridge circuit used in the design. You can adjust the resistor values in the lower legs of the bridge to bend the meter response.

This is an LTspice model that illustrates the effect of changing the resistor value. I have normalized the models to show 0-100% deflection.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=85651;image)

These are the results for 1,3 and 10 Ohms:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=85653;image)

3 Ohms was chosen the design to give the best scale on the meter, for the majority of applications.

Most electrolytic capacitors have an ESR less than 20 Ohms, if they are good.

Note: this model does not include the non-linearity introduced by the 1N5711 diodes.

It is not easy to adapt the circuit for a 1mA meter.



Jay_Diddy_B

For this part you're talking about R10, right?
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on March 01, 2016, 03:02:13 am
hi is there a black and white version of the pcb artwork,as having it in color makes it imposible to use the toner transfer method of making the pcb,cheers Paul.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 01, 2016, 03:29:40 am
hi is there a black and white version of the pcb artwork,as having it in color makes it imposible to use the toner transfer method of making the pcb,cheers Paul.

Are you looking for the SMD version or the thru-hole version?

I can make them available.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 01, 2016, 03:47:47 am
Hi,

Here is the pdf file for toner transfer. I have mirrored the image, so it is ready to use.

I have indicated the size in the file.

This is the SMD version.

Regards,

Jay_Diddy_B

Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 01, 2016, 04:05:58 am
Hi,

Here is the thru hole version.

It matches the layout in this message:

https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg412753/#msg412753 (https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg412753/#msg412753)

I have removed the copper pour and replaced it with a ground trace. It should make the board easier to make.


It is ready to go.

Regards,

Jay_Diddy_B


Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on March 01, 2016, 07:05:59 am
cheers i was after the thru hole version,cheers Paul.m3vuv
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on March 01, 2016, 07:37:38 am
thought the copper pour was better tbh,uses less etchant,is the image mirrored and ready to print and iron on?,cheers.
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on March 01, 2016, 10:25:00 am
Attached you can find my Eagle design of the through hole version.
I just made few changes to the Jay_Diddy_B Design of R.Hirst Design (I left all the names on the silkscreen :)).

The idea was to have a super easy layout that can be toner transferred and also built on a veroboard, since all the holes are on a 100mil grid as the traces.

I have't build it as I ended up building the M12864 DIY Kit instead (http://www.banggood.com/it/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html (http://www.banggood.com/it/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html)), but please let me know if you will build it (post pictures...) and if you have any suggestions.
The attached PDF is mirrored to be toner transferred.
Do not scale it and verify the print dimension against the measurement (70*43mm)

Can someone explain me why you prefer to build this analog version instead of the microcontroller one?
That kit came with a nice PCB, the micro already programmed (if this is your issue), a case is available, it can measure capacitance, ESR with 0.01ohm resolution, it can test also BJTs, MOS… and you can find a great support in this tread:
https://www.eevblog.com/forum/testgear/ (https://www.eevblog.com/forum/testgear/)$20-lcr-esr-transistor-checker-project/

Mauro

Edit: To answer my question, reading Jay_Diddy_B early posts: "In my design, I wanted to see if I could do something useful with a few transistors"
         Well you actually did it great  :-+ and thank you for sharing it.

Edit:Do not use files with version below 1.3. There was a mistake in the routing.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 01, 2016, 10:51:10 am
Hi,

The 5 transistor ESR meter use parts that most people will have in their junk box. The circuit can be built with just about any transistors. The only parts that are critical are the two rectifiers in meter circuit. I used 1N5711.

The $20.00 device is capable of a lot more measurements than the ESR meter.

The ESR meter can measure the capacitors in circuit, this means you don't have to remove them for measurement. There are, of course, some exceptions. If you have two or more capacitors connected in parallel you can not measure the ESR of the individual capacitors.

I also designed the ESR meter Adapter.

(https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/?action=dlattach;attach=77770;image)

(https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/?action=dlattach;attach=77775;image)

This can be found in this thread:

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

In many ways this better than the 5 transistor meter, it is really robust, You can apply a charged capacitor or even line voltage, without damaging the adapter. This is really important if you are working on SMPS, because sooner or later you find a charged capacitor. It does use a few parts that you might not have in your junk box.

Regards,

Jay_Diddy_B

@m3vuv

thought the copper pour was better tbh,uses less etchant,is the image mirrored and ready to print and iron on?,cheers.

The image is mirrored and ready to iron on. I have marked dimensions for you to check.



Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on March 01, 2016, 11:40:09 am
Wow really nice, thank you!!  :-+

Mauro
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on March 01, 2016, 11:52:48 pm
NICE ONE,what a star !,cheers.
Title: Re: 5 Transistor ESR Meter Design
Post by: ledtester on March 02, 2016, 06:38:28 pm
Hi,

The 5 transistor ESR meter use parts that most people will have in their junk box. The circuit can be built with just about any transistors. The only parts that are critical are the two rectifiers in meter circuit. I used 1N5711.

Can you recommend through-hole alternatives for the 1N5711 diodes?
Title: Re: 5 Transistor ESR Meter Design
Post by: fpliuzzi on March 02, 2016, 07:27:25 pm
Quote
Can you recommend through-hole alternatives for the 1N5711 diodes?

The through hole version of the 1N5711 Schottky diode is still readily available...

www.mouser.com/ProductDetail/STMicroelectronics/1N5711/?qs=FITO%2F%2FQgYDnH7pJ7rS2FRA%3D%3D (http://www.mouser.com/ProductDetail/STMicroelectronics/1N5711/?qs=FITO%2F%2FQgYDnH7pJ7rS2FRA%3D%3D)
Title: Re: 5 Transistor ESR Meter Design
Post by: DarkZero on March 16, 2016, 09:26:39 am
can i use BAT41 instead of 1N5711 ?

http://www.vishay.com/docs/85659/bat41.pdf (http://www.vishay.com/docs/85659/bat41.pdf)
Title: Re: 5 Transistor ESR Meter Design
Post by: EntropyWizard on May 05, 2016, 03:13:02 pm
Hi, thought I would post my build of the discrete version of the circuit. It could still use a bit of work on the graphic arts, but I built it about a year and a half ago and it's working fine as is (on the same batteries!)  I don't use it quite as much as I thought I would since I picked up an LRC meter at a university surplus auction cheap.

Main variations on the original are use of 2N4401/2N4403 transistors and SD101A schottky diodes.  I also dropped the voltage to 4V.  The voltage regulator is  a Microchip 1702 4V LDO.  The circuit is built up on a 11 by 24 hole standard protoboard. The protection diodes and the meter tuning resistor are soldered freeform to the terminal posts. The meter is a ancient Micronta (Radio Shack) one I've had sitting around for years. I added a power on LED as well.

The case is 1/4" poplar finished with a stain and oil finish. The panel is 1/8" hard-board (Masonite) coated with black gloss enamel spray paint. The meter face was just marked off using various resistors to calibrate it.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on May 05, 2016, 04:36:06 pm
entwiz,

It looks great!!

Thank you for sharing.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on May 05, 2016, 10:08:23 pm
Hi group,

If anybody has difficulty getting the ESR meter to work, there is some useful information in this thread:

https://www.eevblog.com/forum/projects/jay-diddy-5-transistor-esr-meter/msg933224/#msg933224 (https://www.eevblog.com/forum/projects/jay-diddy-5-transistor-esr-meter/msg933224/#msg933224)

I have posted the waveforms that can be expected.

Here is a schematic showing the DC voltages:

(https://www.eevblog.com/forum/projects/jay-diddy-5-transistor-esr-meter/?action=dlattach;attach=222107;image)

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: anda on October 28, 2016, 03:49:02 pm
Any one have the pcb ready for print for this esr?
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on October 31, 2016, 01:58:14 am
Any one have the pcb ready for print for this esr?

I might be able to help you. What are you looking for?

Are you looking for a picture of the artwork so that you can do toner transfer?

Are you looking for the Gerber files so that you can have the board made?

Are you looking to build a SMD version like my original unit or a thru hole version?

Let me know and I will see if I can help.

Regards,


Jay_Diddy_B

Title: Re: 5 Transistor ESR Meter Design
Post by: w2aew on November 09, 2016, 04:47:23 am
Since I think this 5 transistor ESR meter design is very clever, I decided to take a closer look at it in my latest "Circuit Fun" video:

https://www.youtube.com/watch?v=3fiUZZlveS0 (https://www.youtube.com/watch?v=3fiUZZlveS0)
Title: Re: 5 Transistor ESR Meter Design
Post by: Fisher77 on November 09, 2016, 07:28:59 pm
Any one have the pcb ready for print for this esr?

I might be able to help you. What are you looking for?

Are you looking for a picture of the artwork so that you can do toner transfer?

Are you looking for the Gerber files so that you can have the board made?

Are you looking to build a SMD version like my original unit or a thru hole version?

Let me know and I will see if I can help.

Regards,


Jay_Diddy_B

After reading through this thread, I am confused as to what schematic goes with what. I am interested in the through hole version. Can you post the schematic, the component layout, and image for the through hole toner transfer together?

Thanks
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 10, 2016, 01:33:45 am

After reading through this thread, I am confused as to what schematic goes with what. I am interested in the through hole version. Can you post the schematic, the component layout, and image for the through hole toner transfer together?

Thanks

Hi,

Here is a set of matching documents.

Note R24 is typically 12k Ohms but may need some adjustment. The 10K pot is place in series with the 50uA meter.


For this board:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269082;image)

The board size is 3.00 x 1.75 inches.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Fisher77 on November 11, 2016, 05:43:43 pm
Thanks for posting all the files together Jay_Diddy_B.

What would be the best analog meter to purchase for this?

I have a couple lying around, both are microamperes meteres, and are 50uA. I have no idea what the resistance of them is. I tried looking one up, it is a Modutec 930031-214(number on the front), but I found noting on it. The other just says made in Japan on it. I am fairly new to the electronics game, and have not messed with analog meters till now. I appreciate the help.
Title: Re: 5 Transistor ESR Meter Design
Post by: SeanB on November 11, 2016, 06:05:09 pm
Whichever one looks best to you, and where you can carefully dismantle it to change the scale ( or have a conversion table next to it if not) on it. the circuit will work with pretty much any 50uA meter, as the trimmer pot R24 ( a 10k pot for scaling) will handle pretty much any meter of 50uA, and is simple to calibrate by shorting the leads and setting for full scale on the meter.
Title: Re: 5 Transistor ESR Meter Design
Post by: joseph nicholas on November 11, 2016, 06:43:51 pm
I have searched for a voltmeter for this circuit and it would be better to get a jelly bean analog multimeter to house the circuit board and provide a simple set of test lead connections for the whole unit.   

I found a few on ebay for less than 5 usd. 

The only consideration is if the meter movement could be dissassembled to put the graphics inside.

jnicolas
Title: Re: 5 Transistor ESR Meter Design
Post by: Fisher77 on November 11, 2016, 08:02:08 pm
Whichever one looks best to you, and where you can carefully dismantle it to change the scale ( or have a conversion table next to it if not) on it. the circuit will work with pretty much any 50uA meter, as the trimmer pot R24 ( a 10k pot for scaling) will handle pretty much any meter of 50uA, and is simple to calibrate by shorting the leads and setting for full scale on the meter.

Thanks SeanB.
Title: Re: 5 Transistor ESR Meter Design
Post by: Radio Tech on November 11, 2016, 08:14:21 pm
Thanks for posting the through hole hole files. Have two boards eching now.
Got my interest up after watching Alans video.
Title: Re: 5 Transistor ESR Meter Design
Post by: alin_im on November 11, 2016, 10:01:16 pm
Thank you very much for the design !!!  I have some noob questions if its ok. Can I use 1n4148 diodes instead of es1j and also can I use a 1mA full deflection meter instead of a 50uA if I add a shunt resistor ?

Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 11, 2016, 10:32:39 pm
Thank you very much for the design !!!  I have some noob questions if its ok. Can I use 1n4148 diodes instead of es1j and also can I use a 1mA full deflection meter instead of a 50uA if I add a shunt resistor ?

The ES1J diodes are to provide some level of protection against charged capacitors. The 1n4148 will not provide enough protection.

The circuit is designed to use a 50uA meter movement, it will be difficult to get the circuit to work with a 1mA meter.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: alin_im on November 11, 2016, 11:14:59 pm
Thank you for the advice, I will try with other diodes 1n4007 for example, also do you know where I can get a 50uA  :bullshit: ? On ebay they dont specify this spec, or do you know what I can change in the design to adapt with my 1mA meter?

Thank you very much for the design !!!  I have some noob questions if its ok. Can I use 1n4148 diodes instead of es1j and also can I use a 1mA full deflection meter instead of a 50uA if I add a shunt resistor ?

The ES1J diodes are to provide some level of protection against charged capacitors. The 1n4148 will not provide enough protection.

The circuit is designed to use a 50uA meter movement, it will be difficult to get the circuit to work with a 1mA meter.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 12, 2016, 01:35:15 am
Hi group,

I have started the construction of the thru-hole version of the 5 transistor ESR meter.

Here is a picture of the blank PCB:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269590;image)

This was milled and drilled on my LPKF Protomat C60.

A few people have been asking about the 50uA meter. Here is a couple of pictures of the one that I used:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269592;image)

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269594;image)

It is not critical. You need to be able open the meter to change the scale. This one is 'Hope Sun'. I am sure that 'Hopeless Moon' will work just as well  ;D

The ESR meter does not need to be super accurate, you just getting an indication if a capacitor is good or bad.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: kripton2035 on November 12, 2016, 07:51:03 am
I made the poptronix esr meter (which is more or less like this one but with AOP instead of transistors the principle is the same)
I did not have any suitable meter display like this one.
so I made a small circuit with an LM3914 a small adjustable resistor , and 10 leds, it is more than enought to see if a cap is bad or not.
Title: Re: 5 Transistor ESR Meter Design
Post by: Radio Tech on November 12, 2016, 03:45:42 pm
How would a 1N34A work instead of a 1N5711?
I have now other substitute in my junk and is the only other part I do not have.
Title: Re: 5 Transistor ESR Meter Design
Post by: Fisher77 on November 12, 2016, 04:50:45 pm
Thank you for the advice, I will try with other diodes 1n4007 for example, also do you know where I can get a 50uA? On ebay they dont specify this spec.

Here is a good source for people that live in the UK: https://www.esr.co.uk/electronics/products/frame_test-panel.htm (https://www.esr.co.uk/electronics/products/frame_test-panel.htm)
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 12, 2016, 05:53:50 pm
How would a 1N34A work instead of a 1N5711?
I have now other substitute in my junk and is the only other part I do not have.

The 1N34A should work fine. Try them and let us know.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Fisher77 on November 12, 2016, 07:30:42 pm
Jay_Diddy_B what is the procedure for working out the resistance of R24? I see on the schematic that it has an x to it, so I figure there is some formula you have to work out to get the proper resistance for it. Or is R24 the 10K pot? I am confused again. One schematic shows R24 and a pot, and another shows just the R24, and states 50uA & Pot.

Title: Re: 5 Transistor ESR Meter Design
Post by: SeanB on November 12, 2016, 07:47:23 pm
R24 is the 10k pot. Use to calibrate full scale and then the rest will be approximate, somewhat nonlinear but usable. To get an accurate scale you have to use some low value resistors to mark your scale appropriately.
Title: Re: 5 Transistor ESR Meter Design
Post by: Fisher77 on November 12, 2016, 08:39:37 pm
R24 is the 10k pot. Use to calibrate full scale and then the rest will be approximate, somewhat nonlinear but usable. To get an accurate scale you have to use some low value resistors to mark your scale appropriately.

Thanks SeanB, that cleared it up. What threw me off was that 0ne schematic had a R23, and R24 on it. But I am guessing when Jay_Diddy_B updated the schematic to show the Pot connections he had to label it. If you give me a schematic for a International,Freightliner, etc. truck I can tell you where anything is. Still learning to read the electronics schematics. On the low value resistors, I assume you mean 1%. What values would I need to calibrate the scale?
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 12, 2016, 10:07:51 pm
Hi,

The original calibration procedure was described in this message:

https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg172109/#msg172109 (https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg172109/#msg172109)

You need  5 x 1 Ohm and 4 x 10 Ohm  1% resistors and by using them in various combinations of series and parallel you can get a good selection of values.

I also built a test board described in this message:

https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/msg343855/#msg343855 (https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/msg343855/#msg343855)


(https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/?action=dlattach;attach=70045;image)

(https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/?action=dlattach;attach=70047;image)

(https://www.eevblog.com/forum/projects/esr-meter-adapter-design-and-construction/?action=dlattach;attach=70049;image)

R24

The value of R24 depends a little bit on the meter being used. It is in series with the pot and the meter.

I am in the process of building another meter right now. I will let you know.

Note R24 is typically 12k Ohms but may need some adjustment. The 10K pot is place in series with the 50uA meter.



Regards,

Jay_Diddy_B - recovering ESR_nut

Title: Re: 5 Transistor ESR Meter Design
Post by: Radio Tech on November 12, 2016, 10:45:24 pm
Got my through hole version just about done. Have to play around with the calibration and do some test.
Decided to give an old piece of gear a new identity.
The range switch is now the variable resistor.
Zero ohm switch now has a BNC jack and also connected to the + / -.
Going to put an ON/OFF switch in the other hole.


(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269784;image)
(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269786;image)
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 12, 2016, 11:58:50 pm
Hi group,

I have completed the assembly of the thru-hole version. Here is a picture of the assembled board:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269809;image)

If you are trying to read the colour codes, most of the resistors used are 1 or 2% so they have an extra band.

I also substituted a 3.3 Ohm resistor for R10, because I didn't have any 3.0 Ohms.

Here is a photograph of the board being tested:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269811;image)

I have the board hooked to a General Radio Decade box, out of camera, set to 1 Ohm.

I needed a 12k Ohm resistor in R24 position.

Regards,

Jay_Diddy_B (Recovering ESR_Nut)

Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 13, 2016, 12:48:37 am
I have BC5xx transistors. Could they be substituted?

Wilfred,

You can use pretty much any silicon transistors in the design. Any that have the following spec.

Vce >20V
Hfe > 100
Ic > 50mA

You need 4 NPN and 1 PNP.

The only critical parts are the two diodes D3 and D4. These should be small signal Schottky or 1N34A etc.

Do not use 1N4148  - too much voltage drop or 1N5819 - too much capacitance.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: kripton2035 on November 13, 2016, 08:34:55 am
Hi group,
I have completed the assembly of the thru-hole version. Here is a picture of the assembled board:
(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269809;image)
What are the small pins you can attach hooks on them ? what are their names, where did you find them ?
I came to buy the Keystone test points, but they are really too expensive, and did not find them in europe the shipping is more than the test points !
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 13, 2016, 11:50:54 am
What are the small pins you can attach hooks on them ? what are their names, where did you find them ?
I came to buy the Keystone test points, but they are really too expensive, and did not find them in europe the shipping is more than the test points !

Kripton2035,

I have two types of those pins in my collection. I used Keystone 1502-2 on the board shown. I made my own tool for pressing them.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269948;image)

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269950;image)

They are $0.50 each in small quantities, dropping to $0.20 in large quantities. I was able to buy a bag of them on eBay. They were still expensive around $0.05 each.

I also have a bag of smaller pins made by Mill-Max:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269952;image)

I can't remember where I got them. These ones are designed for 0.032" board.

Try searching for "Turret Solder Terminal" on eBay.

As an alternative try looking for 'vero pins'.

Good Luck !!

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Radio Tech on November 13, 2016, 02:58:11 pm
Time for a bit of troubleshooting now. I can short the leads, zero meter. But when I disconnect the leads my meter reads just below half scale. Disconnect power and meter returns to normal. Not sure if D3 and D4 have a problem in the circuit.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 13, 2016, 05:47:30 pm
Time for a bit of troubleshooting now. I can short the leads, zero meter. But when I disconnect the leads my meter reads just below half scale. Disconnect power and meter returns to normal. Not sure if D3 and D4 have a problem in the circuit.

Hi,

Check this message:

https://www.eevblog.com/forum/projects/jay-diddy-5-transistor-esr-meter/msg933224/#msg933224 (https://www.eevblog.com/forum/projects/jay-diddy-5-transistor-esr-meter/msg933224/#msg933224)

Then report back.

Further to my last comment, check Q5 first. You should have a square wave on Q5 collector. The symptoms you have are consistent with Q5 not working.


Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: alin_im on November 13, 2016, 08:30:32 pm
what type of diodes are d1 and d2 ??? can 1n4007 replace them ? if not what is a replacement for them ?
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 13, 2016, 09:11:55 pm
what type of diodes are d1 and d2 ??? can 1n4007 replace them ? if not what is a replacement for them ?

alin_im and the group,

The diodes D1 and D2 are protection diodes. You can use any diodes from the 1N4001 to 1N4007 family.
They provide some limited protection against damage from a charged capacitor.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Bryan on November 14, 2016, 10:37:04 pm
For those interested in software for creating panel meter faces. Works under Win 10 if you run as administrator and XP compatibility. I am sure there is other software out there.

http://www.tonnesoftware.com/meter2.html (http://www.tonnesoftware.com/meter2.html)
Title: Re: 5 Transistor ESR Meter Design
Post by: bitseeker on November 14, 2016, 11:37:08 pm
Since I think this 5 transistor ESR meter design is very clever, I decided to take a closer look at it in my latest "Circuit Fun" video

Thanks for covering this, Alan. I didn't see the thread when it originally started and it looks like there's quite a bit of new activity as a result.
Title: Re: 5 Transistor ESR Meter Design
Post by: Elrod on December 21, 2016, 06:00:59 pm
Hi all.  I used the Hopesun PM-2 meter in my ESR meter.  I wanted to share my meter scale graphics.  May be useful for someone with this same meter.

Elrod
Title: Re: 5 Transistor ESR Meter Design
Post by: Bryan on December 23, 2016, 03:03:17 am
Tried opening the dxf file in DXFviewer and all that is displayed is a black screen? Tried different encoding options that are available in the viewer, but same thing.
Title: Re: 5 Transistor ESR Meter Design
Post by: alin_im on December 23, 2016, 07:55:38 am
What programs did you use to draw the meter scale  ?

Is there any special program that I can use (except Meter that costs 35 dollars, too much money for one meter) ?

In the worst case I will use Illustrator, but it will take some time.
Title: Re: 5 Transistor ESR Meter Design
Post by: kripton2035 on December 23, 2016, 09:44:46 am
hem ... illustrator is far more money than $35 for one meter ...
Title: Re: 5 Transistor ESR Meter Design
Post by: alin_im on December 23, 2016, 12:08:38 pm
hem ... illustrator is far more money than $35 for one meter ...

I have a friend that has it and can help me, but I wanted something that I can use in the future without the help of others.
Title: Re: 5 Transistor ESR Meter Design
Post by: Elrod on December 23, 2016, 02:41:47 pm
I drew the PM2 scale in QCAD Pro on Linux.  Here is a PNG version as well as an older format DXF file.  Maybe you can open it.
Title: Re: 5 Transistor ESR Meter Design
Post by: felixna on February 25, 2017, 02:27:48 pm
Hi all,

I wanted to share my rebuild of this fine ESR-meter with you. Not the most beautiful build but most parts were already here and it works perfectly!

The instrument is this cheap chinese HUA 85C1 meter: http://www.ebay.de/itm/291493659126 (http://www.ebay.de/itm/291493659126) - not the most precise one (class 2.5 is exaggerated, it's more like a 4), but good for the job.

The scale for the meter was done with Inkscape and is attached in the ZIP file.

Thank you, Jay_Diddy_B for this great circuit!

Cheers,
Felix

Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on February 25, 2017, 10:42:43 pm
Felix,

Congratulations !!!

Looks good, thank you for sharing!!

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Elrod on June 17, 2017, 03:56:22 pm
My ESR meter using the Hopesun meter movement got dropped one time to many.  I had to replace it.  I got a different meter this time so I had to make a different meter scale graphic.  May be useful to someone.  The eBay listing just called it a 50uA meter.  Box has M2D 0-50uA written on it.
Title: Re: 5 Transistor ESR Meter Design
Post by: sasa on August 07, 2017, 08:42:38 am
I have relatively recently made this quite useful circuit. I have used OA91, 1% resistors where is critical, common BC547 and BC557. It works extremely well, as well as with desoldered and in-circuit caps. This is my homemade board.

Since I have no any analog meter, I use plain digital multimeter. For in-circuit measures they are used quite short quality UTP cable wires. due lack of any quality test leads.  In this configuration, perhaps may be simplified a bit to use an op-amp and MCU with a LCD, however I'm quite happy with this bare design as well.

Thank you, Jay_Diddy_B, for this simple and very efficient  circuit!!
Title: Re: 5 Transistor ESR Meter Design
Post by: transistor12 on November 21, 2017, 03:49:23 am
Thank you very much for tru-hole efforts .
Title: Re: 5 Transistor ESR Meter Design
Post by: Efcis on December 28, 2017, 11:43:57 pm
Hi Jay_Diddy_B et al.

1/ What is the reason why C3 and C8 have different values (10nF vs 22nF) ?

2/ Several builders seem to use electrolytics caps for C4 and C6 (2.2 uF). Are their own ESR not too large compared to ceramic / MLCC ones ?

Thanks !
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 29, 2017, 03:30:08 am
Hi Jay_Diddy_B et al.

1/ What is the reason why C3 and C8 have different values (10nF vs 22nF) ?

2/ Several builders seem to use electrolytics caps for C4 and C6 (2.2 uF). Are their own ESR not too large compared to ceramic / MLCC ones ?

Thanks !

1) You can use 22nF in both locations.

2) The ESR of C4 and C6 should be small. <10%, of the resistors they are in series with. If use an electrolytic you can use a larger value to get the low ESR.

Hope this helps.

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: hugo on December 29, 2017, 03:37:58 am
Quote
1/ What is the reason why C3 and C8 have different values (10nF vs 22nF) ?

The LTspice schematic shows both capacitors as 22nF.

Quote
2/ Several builders seem to use electrolytics caps for C4 and C6 (2.2 uF). Are their own ESR not too large compared to ceramic / MLCC ones ?

They have used what they had available I guess, both capacitors are in series with a 33 ohm resistor so ESR does not matter.
Title: Re: 5 Transistor ESR Meter Design
Post by: Thebighat99 on January 23, 2018, 09:00:23 pm
Could someone be so kind to let me know what watt the resistors should be.  I am very new at this but would like to build this.

thanks in advance.
Title: Re: 5 Transistor ESR Meter Design
Post by: EntropyWizard on January 24, 2018, 08:43:51 pm
You should be able to use most any resistors you have available. Most builds seem to be using typical 1/4 or 1/8 watt through hole resistors. The 1/10 watt surface mount resistors should be fine as well.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on January 24, 2018, 11:05:18 pm
Could someone be so kind to let me know what watt the resistors should be.  I am very new at this but would like to build this.

thanks in advance.


I used 1/10W on the surface mount (SMD) version and 1/4W on the through hole version. These are the standard sizes. Nothing special in this design.

Good luck if you decide to build the ESR Meter.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on March 14, 2018, 05:30:23 am
hi mauroh,ive etched your design of board but cant see where the components go,is there a silk screen for it?,tried making p diddys board but found the tracks way to close together!,cheers m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on March 14, 2018, 02:10:46 pm
Attached you can find my update Eagle design of the through hole version I posted 2 years ago where I added the PDF of the "silkscreen" with the component values to be printed and applyed on the top side.  (I also updated the old post).
I just made few changes only to the layout to the Jay_Diddy_B Design of R.Hirst Design (I left all the names on the silkscreen :)).

The idea was to have a super easy layout that can be toner transferred and also built on a veroboard, since all the holes are on a 100mil grid as the traces.

Please let me know if you will build it (post pictures...) and if you have any suggestions.
The attached PDF of the PCB is mirrored to be toner transferred.
Do not scale it and verify the print dimension against the measurement (70*43mm)

Mauro

Edit:Do not use files with version below 1.3. There was a mistake in the routing.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 14, 2018, 09:03:14 pm
Hi,

Looks good!

Thank you for sharing your board layout.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on March 15, 2018, 08:50:27 am
Hi Jay_Diddy_B!!
All credits goes to you for the design and to koogar (Rupert Hirst) for the PCB Layout on Eagle.
I have only tweaked the PCB Layout to be easily built on a perfboard or etched with the press&peal method.

I report here your notes to koogar on the design:

- D1 and D2 can be replaced by 1N4001, 1N4002 etc or 1N4935. These diodes take a beating if you connect a charged capacitor to the terminals.
- D3 and D4 are critical, the 1N5711 will be fine. You need low capacitance small-signal Schotky diodes.
- You want a panel mounted potentiometer for R23. You have to zero the meter to adjust for the lead resistance.

Hope it will help someone to easily build this meter  :-+

Mauro
Title: Re: 5 Transistor ESR Meter Design
Post by: BravoV on March 15, 2018, 09:23:02 am
I report here your notes to koogar on the design:

- D1 and D2 can be replaced by 1N4001, 1N4002 etc or 1N4935. These diodes take a beating if you connect a charged capacitor to the terminals.

Additional report, my friend who successfully built this great ciruit, on D1 & D2 he was using "used" 1N4007 diodes salvaged from dead CFL bulb, and he sort of joked and bragged as they're "proven" to survive high mains voltage and temperature in the bulb.   :-DD
Title: Re: 5 Transistor ESR Meter Design
Post by: joseph nicholas on March 15, 2018, 09:36:34 am
Thanks muroch for your pcb layout for this.  I am waiting for some diodes from ebay to try and complete this circuit.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on March 17, 2018, 10:32:48 pm
hi,nice work,is the  silkscreen pdf mirrored?,73 m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on March 18, 2018, 12:17:42 am
No, only the bottom side is mirrored.
The idea was to print the silkscreen on paper, gluing it on the top side.

My suggestion is to install Eagle and print the bottom/top/silkscreen depending on which method you prefer to use to build the board.
For instance I'm using an old pen plotter (with a permanent marker) to print simple boards like this.
In this case the pdf is useless and I'm using Eagle CAM processor to optimize all the plot parameters.

Mauro
Title: Re: 5 Transistor ESR Meter Design
Post by: joseph nicholas on March 18, 2018, 10:24:17 am
Hi, I'm attempting to use mauroks pdf and the holes dont exactly line up with the vero board but Im going to continue to try to build this when I get all the components together.  It does look doable but lets see. 
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on March 19, 2018, 09:03:25 am
Hi  joseph nicholas, thank you to point this out!!
  the only holes that dosn't line up with the 100mil grid of a perfboard/veroboard, should be the base of the 5 transistors and the power connector.
As you can see in the attached picture, I left some room on each side of the transistors to allow it to be fitted at your convenience.
Regarding the power connector I didn't apply it and used the wires ofthe 9V battery clip instead.

If other holes are misulligned please let me know, I can't see it.
If several holes are misulligned, most probably you need to adjust the print scaling. Do not scale the print to fit the page.

Mauro
Title: Re: 5 Transistor ESR Meter Design
Post by: joseph nicholas on March 19, 2018, 12:02:42 pm
The place I get my printing done seems to think that the pdf file is scaled correctly using the standard settings.  I think everything is close enough although it does seem that the pdf is just a tad small the way it is unless the vero board is off.  Anyway what you have provided is excellent and I think eventually I will get a few of these templates made and start to try to get the soldering started on the back of the vero board.  I suppose the way to go with this is to have it made at a pcb house in china but I prefer to do it like I outlined earlier.

Its amazing the amount of detail and work you have done on this, and thanks again even if I cant get it to work or if there is an error in the design or my construction.  Just a cool fun and very practical project.  I plan to get this stuffed into one of those cheap MF type analog multimeters you find from China.
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on March 19, 2018, 02:19:05 pm
I've added couple of strip connector on the sides of the board and printed the pdf on 2 different laser printers to verify the holes alignment...
As you can see removing all possible rescaling/fitting options on the printers, it looks like it is close to the veraborad I have.

Always take the veraboard with you or a strip connector to verify the dimension of the strip BEFORE etching/press&peel!!!  :)

I've added also the bottom side NOT mirrored, this is usefull as reference, working on the bottom side of the veroboard.

Mauro

Edit:Do not use files with version below 1.3. There was a mistake in the routing.
Title: Re: 5 Transistor ESR Meter Design
Post by: blackdog on March 25, 2018, 10:02:40 am
Hi Jay_Diddy_B,

I liked your design of the ERS meter so much that I thought I would build one too.
On two radio flea market's, I bought some 50uA meters for this ESR meter.

There is only one component that I have changed in the design, and that is the 5V stabilizer.
I had some low power LDO stabilizer in a TO92 housing and that is the: TSTS2950-50
The dropout voltage when loaded with this ESR meter (24mA) is less than 5.5V.
This allows me to extract as much energy from the 9V battery as possible.

Picture time!
To minimize errors, I mark the parts on a print in the diagram, not all parts are marked, because I did not think this was necessary anymore.
(http://www.bramcam.nl/Diversen/JPD-ESR-05.png)

The top of the printed circuit board.
The structure is almost the same as the schematic, I think this is a pleasant way of building electronics.
Top left is the battery connection, the two connection pins at the bottom are for the D.U.T. the diode's ES1J wil come behind the banana jacks.
And the connection pins in the middle are for the meter, the top connection is for the +connection of the meter.
In the blue circle you can see R24, 12K for a 50uA meter, in the yellow circle is the only aberration, the 5V decouplig capacitor C9 under a angle.
(http://www.bramcam.nl/Diversen/JPD-ESR-04.png)


The bottum of the circuitboard, no spaghetti wiring  :-DD
The top wire is the +5V power supply, the wire below that is the connection from Q3 that drives Q5.
And on the bottom is the -rail.
(http://www.bramcam.nl/Diversen/JPD-ESR-03.png)


And yes, he worked on the first power on.  :)
The meter indicates 35uA when measuring a 1 ohm resistor.
(http://www.bramcam.nl/Diversen/JPD-ESR-01.png)


Now it is time to look for a instrument box, I'll show it here when the project is done.
Nice project!

Kind regards,
Bram
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on March 26, 2018, 02:26:35 am
Hi Jay_Diddy_B,

I liked your design of the ERS meter so much that I thought I would build one too.

snip ...

Now it is time to look for a instrument box, I'll show it here when the project is done.
Nice project!

Kind regards,
Bram

Bram,

Thank you for your kind words. The layout that you made looks great !! Thank you for sharing.
I look forward to see the completed project.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: bitseeker on March 26, 2018, 02:33:46 am
Nice job, Bram. I like how your component layout resembles the schematic so well. :-+

Note that "spagetthy" is spelled "spaghetti."
Title: Re: 5 Transistor ESR Meter Design
Post by: joseph nicholas on March 26, 2018, 09:55:57 am
I like the removal of the big 7805 bjt, from the original design.  Nice improvement, makes the circuit look more elegant.
Title: Re: 5 Transistor ESR Meter Design
Post by: blackdog on March 26, 2018, 05:39:07 pm
Hi All,

I would like to have an indication of the condition of the battery.
There are various ways to do this and the most used is an extra dpdt switch so that the meter can also measure the battery voltage.

I wanted to do it differently, so I have an indication that the ESR meter is on and that just before the battery is completely empty the extra power LED goes out.
But watch out!!! if you applied this in your version, then it is not a 5 transistor ESR meter anymore :-)

Take a look at the picture below, this battery level indicator only works with a low dropout regulator like the TS2950-50 i'am using!
My TS2950-50 stops regulating if the input voltage comes below 360mv dropout voltage, that is 200mV lower than the threshold voltage of the transistor BE voltage.
It is possible to to make the indication more soft, if you place a 47K over the base emittor of Q6, the LED wil be of at 6.2V and almost full on at 7V.
Whitout the extra resistor the LED wil be off at 5.5V and full on at 6V.
(http://www.bramcam.nl/Diversen/JPD-ESR-10.png)

I hope you find this a nice addition to this ESR meter.

Kind regards,
Bram


Title: Re: 5 Transistor ESR Meter Design
Post by: blackdog on March 28, 2018, 04:02:57 pm
Hi!

I have done some more steps to finish this ESR meter.
Yesterday I received some material and there was also the regulator of the type: LM2859-50.
This is, I think, better known to you than the TS2950-50 and i tested is and it works fine.

This wil be the box i will use, look at the meter, something is broken....
(http://www.bramcam.nl/Diversen/JPD-ESR-11.png)


I also had some of these smaller meters, but I thought it was less fun.
(http://www.bramcam.nl/Diversen/JPD-ESR-12.png)


It was a bit difficult to open the meter, it seemed that the meter cap was also glued.
(http://www.bramcam.nl/Diversen/JPD-ESR-13.png)


I used the meter scale of Jay_Diddy_B and at printing I adjusted the size for my meter.
Here you can see i'am measuring a 100uF capacitor, the blue version.
(http://www.bramcam.nl/Diversen/JPD-ESR-14.png)


The picture below shows my two "hacks", at the top of the extra transistor that controls the battery LED.
And a coax connection via a 47 Ohm resistor...
Why? look at the pictures below this one.
(http://www.bramcam.nl/Diversen/JPD-ESR-15.png)


With this simple addition, if you connect a scoop via a 47 resistor you can get an impression of the induction of your connected component.
In the case of a capacitor, this is indicated as ESL.
It is also instructive to see what happens when you test a capacitor with long connecting wires, you will see a lot of overshoot on the edges.

Some measurements, both capacitors are 100uF and 16V.
One is a rubicon ZLM series en the other ... not shure.
First the reference, a 1 Ohm resistor with the shortest possible connection wires.
This gives a nice block of signal without abberations.
(http://www.bramcam.nl/Diversen/1-Ohm-Resistor.png)

And now for the measurement of only the blue capacitor with 8mm long connecting wires.
(http://www.bramcam.nl/Diversen/Blue-01.png)


This is the measurement of the Rubicon capacitor with 8mm long connecting wires.
It is visible that the ESR is smaller with this capacitor, but also that there is still quite a bit of induction present because of the relatively long wires.
(http://www.bramcam.nl/Diversen/Rubicon-01.png)


What is extra handy of this hack is that you have an opportunity to see if two capacitors do not resonate in parallel.
Blue capacitor and 0.47uF Cer.
(http://www.bramcam.nl/Diversen/Blue+0.47Cer-01.png)


And now the Rubicon and the 0.47uF Cer, there is a problem... not a good match!
(http://www.bramcam.nl/Diversen/Rubicon+0.47Cer-01.png)


And this is a picture of the rubicon connected with the smales posible wires.
(http://www.bramcam.nl/Diversen/Rubicon-02.png)

And this is the measurement of this setup
(http://www.bramcam.nl/Diversen/Rubicon-Short-Wires.png)


Laters more, time is up!

Kind regards,
Bram
Title: Re: 5 Transistor ESR Meter Design
Post by: h2oo on May 01, 2018, 02:59:41 pm
If I don't have an analog Meter, how do I grade the value measured over a 20k resistor (which replaces the meter in my case)?

or how did the scale of the ESR label overlay has been defined?


Title: Re: 5 Transistor ESR Meter Design
Post by: hugo on May 01, 2018, 11:12:34 pm
Quote
how did the scale of the ESR label overlay has been defined?

It's right here on the first page:

https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg172108/#msg172108 (https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg172108/#msg172108)   ;)

Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 03, 2018, 10:44:59 am
are the 2.2uf caps critical values in this?,im having a job finding them local,would 3.3uf be ok?,cheers Paul m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on August 03, 2018, 05:55:49 pm
are the 2.2uf caps critical values in this?,im having a job finding them local,would 3.3uf be ok?,cheers Paul m3vuv.

The 2.2uF is not critical, you can use any value up to 47uF. I used ceramic, but other people have built the circuit with electrolytic capacitors.

Good luck with the project!

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 03, 2018, 07:48:51 pm
cool,thanks for that.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 12, 2018, 09:32:09 am
hi,i just built this using the mirrored image for the pcb traces and the un mirrored silkscreen on the top of the board,looks like the transistor pinouts are inverted,am i going mad?,cheers m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 12, 2018, 02:23:15 pm
gave up on the pcb idea,building it on veroboard now,im checking each stage as i go,the oscillator is running at 61.3khz measured with my freq counter,does that sound ok,i thought it was supposed to be 100khz?,cheers Paul m3vuv.73
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on August 14, 2018, 12:24:40 pm
gave up on the pcb idea,building it on veroboard now,im checking each stage as i go,the oscillator is running at 61.3khz measured with my freq counter,does that sound ok,i thought it was supposed to be 100khz?,cheers Paul m3vuv.73

Paul and the group,

I would start by checking the value of C1, the 1.5nF capacitor in the oscillator. It could have a high tolerance.

W2AEW did a video on this circuit. You can find it here:

https://www.youtube.com/watch?v=3fiUZZlveS0 (https://www.youtube.com/watch?v=3fiUZZlveS0)

Here is a screen shot from the video:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=497513;image)

If you look the oscillation is about 5.3 div at 2us/div so 10.6us = 94 kHz

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on August 14, 2018, 12:31:57 pm
i must say these cap ESR sense things are one of the most interesting LTspice thingy to play in LTspice. I have tried (in LTspice) a few types of oscillators, versions of pulsing the drive current, input protection for surge and a supply voltage like a single 3.6v cell.

Snip ...


Can you post (attach) the LTspice Files (.asc) the .GIF files are hard to read.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 15, 2018, 06:38:25 pm
hi mauroh,is there any way you can post the thru hole pfd toner transfer and the coresponding silkscreen?,ive etched the board from the mirrored pdf and etched it but no way does the silkscreen marry up to it,sort of mirrored ,can you post a matching set but say whats ready to print,ie no mirroring and whats not,cheers Paul m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 16, 2018, 05:08:39 pm
just a heads up,i spent ages building the thru hole version as posted on page 5,if you trace out the tracks from Q4 you will see the base and emitter pinouts are wrong,the base and collector are inverted,the silkscreen is wrong for the type of transistor used!!,regards Paul m3vuv .
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on August 17, 2018, 02:12:07 am
just a heads up,i spent ages building the thru hole version as posted on page 5,if you trace out the tracks from Q4 you will see the base and emitter pinouts are wrong,the base and collector are inverted,the silkscreen is wrong for the type of transistor used!!,regards Paul m3vuv .

Paul,

I am not too sure what you mean. Here is the artwork:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269082;image)


This follows the convention that boards are drawn with the component side on top, even if it is a single-sided board.

And here is a picture of the assembled (working) board:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=269809;image)

And here is a picture from the 2N3904 datasheet:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=499343;image)

It looks right to me.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 17, 2018, 09:12:18 am
its the board that Mauro did in talking about on page 5 ,check out Q4 and how it is on the silkscreen,unfortunatly your artwork is no good to me as i need to toner transfer it so needs to be black and white also the component markings will screw things up,regards paul.
Title: Re: 5 Transistor ESR Meter Design
Post by: mikerj on August 17, 2018, 09:32:39 am
There is a toner transfer PDF version of Jay's board attached to his original post.
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on August 17, 2018, 05:55:09 pm
Hi Paul, I've verified the files I posted and I can't find any issue.
Q4 looks fine to me with emitter, base and collector in the same position as in the original Jay_Diddy_B design.

Edit: "My design" is actually the original Jay_Diddy_B design, I just slightly modified a R.Hirst Eagle PCB to make it more veroboard friendly with all the holes on a 100mils grid and toner transfer friendly with all the traces enlarged.

Also the silkscreen match with the PCB.
I tried to overlay the mirrored image to be use for the toner transfer method with the silkscreen and everything seems to be aligned.
Can you please tell me which transistors have you used?
What exactly is not matching up?

Mauro
Title: Re: 5 Transistor ESR Meter Design
Post by: battlecoder on August 18, 2018, 09:27:09 pm
This is a really smart design, thanks for sharing, Jay_Diddy_B.
I have one of those Transistor testers that can measure ESR, but I was looking into getting a dedicated device for that task alone, so I think I'll be building this one.
I'll need to get the 50uA analog meter first, but once I do that I'll post my pictures here.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on September 05, 2018, 09:47:28 am
well ive etched a board from the design on page 5,ive printed the toner pdf as is without mirroring,the silkscreen pdf doesent match up unless i mirror it,then its all inverted,is there a set of both pcb artwork ie to etch and silkscreen ready to go as is without mirroring,p.s ive got self adhesive photo paper for the silkscreen,this is driving me nuts!,has it actualy been build with the files provided and tested?,cheers m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on September 05, 2018, 10:58:34 am
Hi Paul, I think I've got your issue now...
As always, depending on witch proccess you are using i.e. P&P, photo-etching, veroboard, you should check If you need to mirror or not the image provided.

In your case, you should have used the not mirrored file provided here for the copper side:
https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg1456176/#msg1456176 (https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg1456176/#msg1456176)

Since you already etched the board mirrored, you could just mount all the components on the copper side, bending the center pin of the transistors in the opposite direction and mounting the voltage regulator facing down.
The only component you will not be able to fit will be the power connector, but you can just use the wires of the 9V battery clip.

Please let me know if this will work for you.

I mounted mine on a piece of veroboard and giftged to a friend...

Mauro
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on September 05, 2018, 01:24:24 pm
i etched the board with the pcb tonner pdf on page 5 and corresponding silkscreen pdf( as p diddy said the pcb etch was mirrored and ready to print i printed and etched it without mirroring it,ive tried all ways none seems to match!,cheers m3vuv. ps . didnt mirror the silkscreen just printed it and stuck it on the pcb as is,something is wrong im sure.
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on September 05, 2018, 02:55:55 pm
Can you please post a picture of your board?

As I wrote, to save the already etched board you can forget abou the silkscren and since there are no components with more than 3 pins you can easily mount all the components on the copper side, or bend the pins of the transistors and mount the voltage regulator facing down.

You don't like this solution?

Mauro
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on September 05, 2018, 11:26:06 pm
i think ive sorted it,ive used the unmirrored pcb track layout with the un mirrored silkscreen,im just waiting for the board to etch,ill keep you posted cheers,m3vuv 73
Title: Re: 5 Transistor ESR Meter Design
Post by: karchiba on October 22, 2018, 11:29:35 pm
Good afternoon all,

I have built Jay_Diddy_B's original circuit, on a perf-board, and it seems to be measuring very well with test resistors and known capacitors.

I do have one issue that I'm trying to understand...

When the DUT terminals are left disconnected, there is ~10uA of idle current going through the meter.
I assume it is my choice of diodes D1 and D2... I used 1N4003's, which have a reverse leakage current of 1.1uA, and a Forward Voltage of 0.63v.  I am assuming that these Diodes are used to dissipate voltage which may be contained in the DUT.

I have looked at the graph that the designer (THANK YOU Jay_Diddy_B, it's fantastic!) created, and it does seem that his numbers do show some idle current flowing through the meter.  I also looked at the video that W2AEW created, which was extremely helpful to understand how the circuit worked, and it did show some current without a DUT.

Any suggestions as to a better component choice for the diodes?
Could these be the source of the voltage difference off the bridge which could be showing as the 10uA that I'm measuring?   
Does this 10uA of idle current compare with other builders of this circuit?

Thank you all!  I really am enjoying this build.

_karchiba

Title: Re: 5 Transistor ESR Meter Design
Post by: Mikeva on November 22, 2018, 08:44:28 am
Hi everybody,
I also trying to build this esr meter myself but something goes wrong.
Im using the Mauro's layout for the breadboard.All the components are the correct ones except the two 2.2 uf caps which i 've used electrolytics.
The thing is that i do get the right voltages up to Q3 but after the Q3 somethings goes wrong.
My meter says 1.9v on the Q4 collector and 1.4v on the collector of Q5.These ara way lower compare to the values that Jay Diddy posted.

Also in the R24 possition should i use 12k as you guys or should i use  this formula: 1800 ohm(50uAmeter) + 10k/2(pot) -7500ohms=700ohm?
If anyone can help it would be great!
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on November 22, 2018, 03:07:15 pm
Hi everybody,
I also trying to build this esr meter myself but something goes wrong.
Im using the Mauro's layout for the breadboard.All the components are the correct ones except the two 2.2 uf caps which i 've used electrolytics.
The thing is that i do get the right voltages up to Q3 but after the Q3 somethings goes wrong.
My meter says 1.9v on the Q4 collector and 1.4v on the collector of Q5.These ara way lower compare to the values that Jay Diddy posted.

Also in the R24 possition should i use 12k as you guys or should i use  this formula: 1800 ohm(50uAmeter) + 10k/2(pot) -7500ohms=700ohm?
If anyone can help it would be great!

Mikeva,

(https://www.eevblog.com/forum/projects/jay-diddy-5-transistor-esr-meter/?action=dlattach;attach=222107;image)

What voltage do you measure on the bases of the transistors?

The base voltage should be 1.3V

This means the emitter voltage = 1.3 - Vbe = 0.65V

Ie = 0.65V /Re = 2mA

Ic is Ie - Ib, Ib is small so Ic = Ie

Vcollector = Vsupply - Ic x Rc = 5V - (2mA x 1.2k  \$\Omega\$) = 5 - 2.4V = 2.6V

Check the supply voltage is 5V.

Check the values of the 330 \$\Omega\$ and 1.2k \$\Omega\$ resistors.

Check the transistor connections.


Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Mikeva on November 22, 2018, 03:36:39 pm
Hi Jay!

So at the momment i'doublechecking my conections and so far seems ok.
Regarding the voltages  i measure:
Q4
collector=1.55
base=1.9
emitter=1.19

Q5
collector=1.9
base=1.26
emitter=0.58

from the regulator  i measure 4.98v with fresh battery.
checked all resistors-ok


Thanks for your reply Jay.
And thanks for the nice work you did about the meter!
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on December 09, 2018, 08:19:13 pm
well i gave up on building the pcb version of this,i made it manhatan style,the only issue i have is with the test leads shorted i adjust it to fsd,then with nothing conected to the test leads the meter sits at about 30% of full scale,als all the esr calibration readings are only about 50% of what they should be,ie 2 ohms reads 1,10 ohm reads about 2.5,any ideas?,the diodes i used were some old oa series i had kicking about,would bat 85 diodes be better,im assuming the screwy readingd are down to diodes being non linearcant fathom why it sits a third way up the scale tho with nothing conected!,cheers m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 10, 2018, 04:23:58 pm
well i gave up on building the pcb version of this,i made it manhatan style,the only issue i have is with the test leads shorted i adjust it to fsd,then with nothing conected to the test leads the meter sits at about 30% of full scale,als all the esr calibration readings are only about 50% of what they should be,ie 2 ohms reads 1,10 ohm reads about 2.5,any ideas?,the diodes i used were some old oa series i had kicking about,would bat 85 diodes be better,im assuming the screwy readingd are down to diodes being non linearcant fathom why it sits a third way up the scale tho with nothing conected!,cheers m3vuv.

I am sorry to hear that you have are trouble getting the circuit to work.

I would suggest that you start by measuring the voltages at the various place in the circuit. The values are shown in the schematic in reply 204 of this thread.

Do you have access to an oscilloscope and a camera? can you post pictures of the waveforms?

I would also suggest looking at this video produced by W2AEW

https://www.youtube.com/watch?v=3fiUZZlveS0 (https://www.youtube.com/watch?v=3fiUZZlveS0)

Let us know what you find.

Regards,
Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on December 11, 2018, 02:20:02 am
dont get me wrong,it does work quite well,its just the meter sitting a third way off the bottom makes it awkward as the max esr tops out at about 10 ohm,ive redrawn the scale to match,i did check voltages,if i remember q5 collector was at about 2.9 volts,wondered if it was the diodes,if i decreased r21  slightly do you think it would help?,cheers m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on December 11, 2018, 04:09:28 pm
well,ive fitted mullard oa47 diodes inn place of d3 and d4,its made no difference(the needle still sits at 20% deflection with input open,ive checked all resistor values,(they seem spot on ( all 5% tolerance),the voltage readings i get are as follows ,left to right,originals first,mine in brackets. 4.98(4.990) 4.56 (4.533) 2.42 (2.748)   1.29 (1.286)  2.80 (2.81)  2.78 (2.652)  1.29  (1.295),i will post some screenshots from the scope later,ok.,im pulling my hair out now!! lol,73 m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on December 11, 2018, 06:46:04 pm
heres some scope shots,taken at the voltage test points,left to right on schematic.,may have tio upload them over a few posts due to file sizes!
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on December 11, 2018, 06:48:30 pm
and againe
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on December 11, 2018, 06:50:42 pm
and againe
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on December 12, 2018, 01:45:27 am
disregard the last pic heres q5 collector.its at .5v/divand .1ms/ div.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 12, 2018, 10:42:00 am
well,ive fitted mullard oa47 diodes inn place of d3 and d4,its made no difference(the needle still sits at 20% deflection with input open,ive checked all resistor values,(they seem spot on ( all 5% tolerance),the voltage readings i get are as follows ,left to right,originals first,mine in brackets. 4.98(4.990) 4.56 (4.533) 2.42 (2.748)   1.29 (1.286)  2.80 (2.81)  2.78 (2.652)  1.29  (1.295),i will post some screenshots from the scope later,ok.,im pulling my hair out now!! lol,73 m3vuv.

M3VUV,

The DC voltages at the various points are correct. This means that all the parts that determine the DC voltages are correct.

The parts with the blue check marks are correct.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=594730;image)

The circuitry in the emitter of the transistors, the 33 \$\Omega\$ resistors and the 2.2uF capacitors impacts the AC gain of these amplifier stages.

These 2.2uF capacitors have been discussed before. I used ceramic capacitors in the prototype. Other people have used low ESR electrolytic capacitors. If you use electrolytic capacitors you can increase the value to get a lower ESR. If the ESR is too high it will reduce the gain of these amplifier stages. Try 47uF or 100uF 105C low ESR electrolytic capacitors.

Operating Frequency

You say that the Tektronix 453 scope is set to 0.1ms/div. The UNCAL lights are on for the timebase and the vertical inputs:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=594736;image)

The variable timebase slows the time/div by up to 2.5 times. So if the UNCAL light is on the timebase is between 0.1 and 0.25ms/div

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=594742;image)

To extinguish the UNCAL lights, turn the red knobs on the vertical controls clockwise. There is normally a click, a switch, and the lights will go off. Do the same with the red knob on the timebase.

x10 Horizontal Magnification

The Tektronix 453 has a Horizontal magnifier. This should be set to off and the MAG light should be off:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=594748;image)

Make sure that the Horizontal Mag is set to off.

If I assume that the timebase is 0.1ms/div, the period of the waveform shown is about 1.5 div or 0.15ms
This means the frequency is only 6kHz and 10 times lower than it should be. Check the value of C2 in the oscillator section. It should be 1.5nF, 1500pF.

Regards,

Jay_Diddy_B

Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 12, 2018, 11:12:36 am
Hi M3VUV,

I have looked at this some more. This waveform is wrong:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=594181;image)

I modified my LTspice model so I could look at possible faults that would cause this:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=594772;image)

If the base capacitor, C3 in the LTspice model, is 1nF instead of 10nF it will cause the same waveform. The current through R22 is the same as meter deflection.

If C3 (LTspice designation) is the correct value, 10nF there is no meter deflection.

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=594778;image)


If C3 is too low there will be meter deflection.


(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=594784;image)

Check or replace this capacitor on your hardware.


Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on December 12, 2018, 04:44:24 pm
Well c3 was out of spec,changed and its fine,reads a bit low on high readings>5 ohm but thats ok,included some pics the last pic is a .6ohm resistor,cheers for your help,73 mvuv Paul.
Title: Re: 5 Transistor ESR Meter Design
Post by: LeoH on December 17, 2018, 01:58:05 am
Hello all,

I followed a procedure (https://www.neatcircuits.com/meter-mult.htm, (https://www.neatcircuits.com/meter-mult.htm,) Method #2, Section 1 Voltmeters) to help estimate my panel meter's internal resistance and came out to be about 7500 ohm. With this value for internal resistance of the meter, will R24 still necessary and what will be the recommended value for it?

This is the meter I got recently  for this project:

 
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on December 17, 2018, 02:15:26 am
if it helps i left out r 24,i just used a 20k multiturn pot instead of 10k,no reason its just what i had,r23/4 do is make it possible to zero the meter,ie go fully to the right with the test leads shorted!
Title: Re: 5 Transistor ESR Meter Design
Post by: Autoexe3219 on December 27, 2018, 02:22:44 pm
Hey Guys

Here are the PCB files for a through hole version .

(http://homepage.ntlworld.com/ruperthirst/Forum%20Files/runawaybrainz.blogspot/ESR%20Project/5%20Transistor%20ESR%20Through%20Hole.png)

(http://homepage.ntlworld.com/ruperthirst/Forum%20Files/runawaybrainz.blogspot/ESR%20Project/5%20Transistor%20ESR%20Through%20Hole%20SCH.png)

Eagle PCB Files Attached

Cheers

Rupert

What is the voltage of the capacitor(C2~C11)? 63V?
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on December 31, 2018, 11:01:44 pm
Hi,

(https://www.eevblog.com/forum/projects/jay-diddy-5-transistor-esr-meter/?action=dlattach;attach=222107;image)

The capacitor on the left, C10, has the battery voltage, so use a 25V part.
All the other capacitors have less than 5V on them. You can use any capacitors with a voltage rating with a voltage rating of greater than 5V. Most of the capacitors in the prototype would have been 25V or 50V parts.

Some people have used electrolytic capacitor in the C4 and C6 positions. If you do you can use larger values 10uF to 100uF with a 6.3V or greater voltage rating. They should be low ESR electrolytic capacitors.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: battlecoder on January 01, 2019, 12:04:58 am
Thanks again, Jay_Diddy_B for sharing such a fantastic circuit.
Here are some pics of my build. Not the fanciest one but it gets the job done.

The PCB is the through-hole design you shared. Toner-transfered.
I got the meter from this ebay listing (https://www.ebay.com/itm/50uA-30A-DC-Ammeter-5V-300V-DC-AC-Voltmeter-85C1-85L1-Analog-Panel-Meter-65x56mm/401335524600).
For my build/components R24 had to be around 20 ohm. Don't know if that's reasonable or normal, but it seems to be working properly.

The LED was an afterthough so it's soldered directly to the leads of two resistors. (Yikes) Please ignore all the reinforcement I had to add around the rocker switch; I was working with a drill since my dremel is currently out of service and things got slightly out of hand  ::).
Title: Re: 5 Transistor ESR Meter Design
Post by: kripton2035 on January 01, 2019, 07:29:25 am
well it's a really clean build ! congrats.
Title: Re: 5 Transistor ESR Meter Design
Post by: LeoH on February 19, 2019, 02:21:28 am
Hi Mauro,

After trobleshooting my board, I noticed that there is a track overlap in the version of yours.

I imported the project files to KiCad and to be certain, compared against the toner transfer provided.

Then the base voltage of Q4 measured correctly against the reference and meter deflected properly.

Check the figures.

Thank you!

Leonardo

Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on February 20, 2019, 11:04:09 am
Hi Leonardo, thank you so much for the correction and sorry everyone for the mistake.
Attached you can find the corrected files. To be safe I've also updated the attachements on the old posts.

I think this will solve the mistery of the M3VUV board not working properly.

Thank you
Mauro

Edit:Do not use files with version below 1.3. There was a mistake in the routing.
Title: Re: 5 Transistor ESR Meter Design
Post by: bd139 on April 07, 2019, 04:51:38 pm
Big thanks to Jay_Diddy_B due. A wonderful circuit that works nicely  :-+

(https://i.imgur.com/yFlkQKp.jpg)

(https://i.imgur.com/aI30PeR.jpg)
Title: Re: 5 Transistor ESR Meter Design
Post by: picofarad on May 01, 2019, 08:56:15 pm
Nice build! I'm building this ESR meter too. I see that you used a 100uA meter. What value did you use for R24 and the pot? The only ammeter I was able to find cheaply is a 100uA but I'm struggling to find the right value for R24.

I'm also hoping that Jay_Diddy_B will help me to figure out the right value!
Title: Re: 5 Transistor ESR Meter Design
Post by: bd139 on May 01, 2019, 09:10:12 pm
I can't remember off the top of my head and didn't write it down unfortunately ... I'll go and take it to bits and have a look. Give me a couple of mins  :-DD

Edit: ok I had a look and it was literally just the 10k pot and the meter movement across C5 (22n one). No series resistor. Movements are difficult to blow up with the source impedance of that circuit so I must have just skipped it. Works fine though!

Got to say that this thing has saved me a fortune in capacitors so far!
Title: Re: 5 Transistor ESR Meter Design
Post by: picofarad on May 01, 2019, 09:59:20 pm
Oh thanks! I'll try bypassing R24. I've already etched and partially populated my board... waiting for those 1N5711 diodes to arrive  :palm:
Title: Re: 5 Transistor ESR Meter Design
Post by: bd139 on May 01, 2019, 10:00:27 pm
Good luck. Any problems, post back  :-+
Title: Re: 5 Transistor ESR Meter Design
Post by: picofarad on June 01, 2019, 09:52:50 am
So, finally, the last components arrived (the diodes) and I've completed the build. Initially, it didn't work just right. After some troubleshooting that led to discovering an error in my pcb layout (basically, the collector of Q3 was shorted to ground), it worked perfectly. It's incredible sensitive. I'm gonna to test different probing cables since I've found that using regular alligator clip cables (those kits with 10 jumpers from ebay) it's impossible to zero the meter due to the cable resistence.

Anyway, great instrument! Now it's time for the boring part: the enclosure building. :palm:
Title: Re: 5 Transistor ESR Meter Design
Post by: Richard9026 on June 02, 2019, 01:15:15 pm
Hi!
I made the circuit, everything is working fine (all DC voltages match + 89,5khz oscillator frequency) but I need a higher current to drive the 250uA VU meter that I got. Without any resistance in series with the meter (no R23 and R24) I get 160uA with the probes shorted.
What do I need to modify to increase the current output? Without affecting the scale deflexion.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on June 03, 2019, 01:45:37 am
Richard and the group,

If you want to experiment with the circuit, you can try this modification:

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=753570;image)

It works in LTspice, you will have to play with the meter circuit. Start with a 4.7K pot in series with the meter.

This modification increases the current consumption to about 22mA. Not a problem if you use the ESR meter occasionally.

Let us know if this works.

Regards,

Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: Richard9026 on June 04, 2019, 05:54:55 am
 Yes, this circuit modification works just right! Now I can peak my M68501 250uA vu meter!
I will post a detailed analysis and measurements later.
Title: Re: 5 Transistor ESR Meter Design
Post by: Richard9026 on June 04, 2019, 10:02:30 pm
For the modified circuit:

Measurements are taken with the M2038 voltammeter, on the 0,75mA / x1 range (that means 750uA full scale). The scale is marked 0-150, so multiply by 5 to obtain the uA value.

(https://i.lensdump.com/i/Wnifoi.jpg)

Its internal resistance, measured on this range (0,75ma x1) with a multimeter is 21,7ohms

Connecting the meter to the circuit (no pot/resistor in series) and shorting the probes, I get a reading of exactly 70, multiplying by 5 -> 350uA

Measuring the voltage on the terminals of the voltammeter: 0,007V

The ESR deflection on the linear scale of the voltammeter is the same as yours:

Your meter deflection (taken from page 1):

(https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/?action=dlattach;attach=37886;image)

Notice that the 2 ohm inscription is on the left side of the middle line.

The voltammeter deflection is the same as above, if I connect a 2 ohm load across the probes of the circuit, it shows 32 -> 160 uA, that's right below 175uA (half of 350uA).

But I got issues when I use a VU meter.

I don't think that the circuit is the problem, because when connecting the voltammeter, that has a linear scale, the deflection is the same as yours.

The VU meters:

(https://i.lensdump.com/i/Wnjie3.jpg)

They both have the same "problem".
 
I don't think it's a problem, maybe is something that vu meters do, and maybe you guys know:

So, I connected the meter circuit as below:

(https://i.lensdump.com/i/Wnjjy0.jpg)

With the help of the 250k pot, I can adjust/peak the needle of the VU meter, and the voltammeter offers a precise reading of the current passing thru the VU meter.

So I peaked the VU meter (capacitor probes shorted):

(https://i.lensdump.com/i/WnjIRD.jpg)

I get a reading of 57,5 -> 287,5uA, let s call this the full deflection point.

Logically, the mid point will be at 57,5/2= 28,75 -> 143,7uA

I adjusted the pot so I can get the needle right in the middle:


(https://i.lensdump.com/i/WnjZ7q.jpg)

BUT I get a reading of 22 -> 110uA.

This means that the mid point is shifted 33uA below what it should be (110ua instead of 143ua) and the delflection on the VU meter would look like this:

(https://i.lensdump.com/i/WnjgUA.jpg)

The left side (the higher ESR values) have more space on the scale than the ones on the right side (the lower ESR values). This makes the reading of low ESR values harder, that is a little of a problem.

At the beginning, I mentioned that a 2 ohm reading will be at the left side of the scale.
If I connect a 2 ohm resistance at the capacitor probes:

(https://i.lensdump.com/i/WnjtIM.jpg)

See, the needle is in the right side of the scale...

Why is it so? Are the VU meters not linear?  I get the exact same problem with the black grundig vu meter, the mid point is not at the half of the full curent deflection.

Thanks!
Title: Re: 5 Transistor ESR Meter Design
Post by: cpt.armadillo on June 05, 2019, 09:18:25 pm
From https://en.wikipedia.org/wiki/VU_meter (https://en.wikipedia.org/wiki/VU_meter), it looks like it is not going to act linearly like a simple ammeter or voltmeter. I won't pretend to understand it but audio stuff often ends up using dB scales.
Title: Re: 5 Transistor ESR Meter Design
Post by: Jay_Diddy_B on June 06, 2019, 02:12:44 am

snip ...

Why is it so? Are the VU meters not linear?  I get the exact same problem with the black grundig vu meter, the mid point is not at the half of the full curent deflection.

Thanks!

I am not sure about the VU Meters. They are certainly not precision instruments.

It is possible that they are non-linear.

You will have to make a custom scale.

Have a look at this message:

https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg172109/#msg172109 (https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg172109/#msg172109)

Regards,
Jay_Diddy_B
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on June 19, 2019, 12:04:11 pm
are these mirrored,well except the silkscreen.
Title: Re: 5 Transistor ESR Meter Design
Post by: kkamel on July 15, 2019, 07:12:38 am
Hi Jay_Diddy_B,
Thanks for your excellent work and thanks for sharing it with us.
I did prepare all the components except of course 1N5711, can’t find it at all can I use BAT85 I can scavenge them from an old board?
I have the Multi-Function Tester - TC1 but I need to make in-circuit testing.
Thanks again,
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 12, 2019, 12:23:48 am
seems very odd to me, how so many have supposedly built this and had it work before the routing mistake was spotted!!!!
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 12, 2019, 04:51:10 pm
hi all,ive built this but have no meter movement,any ideas?,would send some scope pics but cant a my scope just died!,its oscillating at 80khz ,so that parts ok,the meter movement checks out ok,ive took some pic of variouse voltages,hope they display ok,find attached,any pointers on what wrong?,cheers paul.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 12, 2019, 04:52:47 pm
meant to say in my last post the readings were with the test points open.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 14, 2019, 09:35:14 am
anyone help ?
Title: Re: 5 Transistor ESR Meter Design
Post by: Cliff Matthews on August 16, 2019, 01:56:15 pm
anyone help ?
You've posted on the forum 173 times, you should know jpg files can be uploaded..  |O

If by chance, you didn't have a free image program like IrfanView, I'll post the the useful one.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 17, 2019, 03:03:26 pm
thanks for that,i didnt know about the files,ive attached the pic of my various readings,anyone have any idea why its not working?,ps the movement is new and working.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 19, 2019, 05:57:32 pm
well ive solved one problem and i have another,when building this i put a linkin place of the 10k pot as ive got mine on the front panel,i had forgot to solder one side of the link,anyway i soldered it,not the meter is hard over to the right with test points open,the only way i can get the meter to read at zero ie left,is by removing c8 22nf,ive checked all the cap values etc,for  c4+c6 im using 100uf electrolytics,any ideas?,cheers m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 20, 2019, 12:57:33 pm
well it looks like ive found the issue,ive been building this using the design for the pcb from mauroh,in short its a total fuck up,ive traced it thru after building it,the leg of c3 that should go to q4 base,his goes to q5 base and c8 is going to the base of q4 not q5,why to ppl not build there desigh of a pcb before releasing it?,ffs what a fuck up!,lost count of the hours ive spent on this fuck up and wasted copper clad,the cuircuit works well as i built it manhatan style a while ago,just maurohs routing is a
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 20, 2019, 12:59:32 pm
well it looks like ive found the issue,ive been building this using the design for the pcb from mauroh,in short its a total fuck up,ive traced it thru after building it,the leg of c3 that should go to q4 base,his goes to q5 base and c8 is going to the base of q4 not q5,why to ppl not build there desigh of a pcb before releasing it?,ffs what a fuck up!,lost count of the hours ive spent on this fuck up and wasted copper clad,the cuircuit works well as i built it manhatan style a while ago,just maurohs routing is a fuck up even 2nd time around!
Title: Re: 5 Transistor ESR Meter Design
Post by: bd139 on August 20, 2019, 01:05:25 pm
Joy. At least you got to the bottom of it. Perhaps there should be a warning in this thread.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 20, 2019, 02:29:59 pm
makes me laugh at the amount of ppl have built this and supposidly had it work,ive had various attempts at building this over the last few years,it was only today i figured it out,i made it on thin pcb so holding it up to the window could see thr to where the tracks went,supprising its not been spotted before,im just etching jdiddys original,we will see how that fairs!
Title: Re: 5 Transistor ESR Meter Design
Post by: bd139 on August 20, 2019, 02:36:50 pm
This used to be a design feature in some of the old electronics magazines I read when I was a kid :-DD

Think mine only worked because I did it from the schematic rather than the PCB layouts.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 20, 2019, 04:24:05 pm
thats the same as my first one was made manhattan style from the schematic.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 20, 2019, 09:57:56 pm
Well p diddys pcb worked like a charm strait off,ppl need warning about mauros pcb layout,its plain wrong,cant ever work,wish i had never of seen it with all the time and money wasted!!
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on August 22, 2019, 01:41:28 am
Dear m3vuv,
    I apologize for the trouble I caused to you and to someone else that used my incorrect files....
Just to understand what happened and to fix further mistakes, can you please tell me which version of my PCB Layout have you used?
The 1.3 that is the latest one should be correct.
There was a trace overlap in the previous versions that was spotted by another forum member on February 2019, see this: https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg2213103/#msg2213103 (https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/msg2213103/#msg2213103)
Please let me know if you have found another issue.
When I uploaded the corrected files, I delated all the previous one from all my posts in this thread and now I'm sure all the files are updated.
Please let me know
Mauro

If you use mauroh PCB Layout, do not use files with version below 1.3. There was a mistake in the routing.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 22, 2019, 09:05:50 am
Hi i used the latest version of your pcb layout,you have the base conections inverted,ie what routes to base of q3 should go to the base of q4 and what goes to the base of q4 should go to q3,regards m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 22, 2019, 03:19:35 pm
heres some pics of the one i just built,reads slightly high as i need to tweak the meter series resistor.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 22, 2019, 03:22:12 pm
not all uploaded.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 23, 2019, 08:10:10 am
is there anyway another transistor could be added onto this so it can drive a 1ma fsd meter movement as ive some lovely big meters in cases from the 1960s but all 1ma fsd.,also an add on to check shorted caps maybe?
Title: Re: 5 Transistor ESR Meter Design
Post by: bd139 on August 23, 2019, 12:26:39 pm
I think you'd need a higher supply voltage and much lower impedance at the actual rectifier bridge I reckon before that would be possible. Adding emitter followers after Q4/Q5 might do the trick but I haven't simulated it.

Nice looking build BTW  :-+
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 25, 2019, 11:02:51 am
your r15 680 is marked as r14 on mine,says 27k originaly,do you have them mixed up?,thats on the high power mod.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on August 30, 2019, 10:26:32 am
whats going on here?,the both schematics seemed to have a mix up with r12 -13-14-15 and 16,both shematics are different also which one corresponds to the thru hole component/silkscreen?,makes it hard work with silly cockups like that,can it be sorted?.cheers paul m3vuv.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on September 02, 2019, 01:46:00 pm
so mr diddy can you explain which schematic corresponds to which silscreen(ie component placement) pic?
Title: Re: 5 Transistor ESR Meter Design
Post by: mauroh on September 03, 2019, 10:26:05 am
Hi m3vuv,
   I just played spot the difference for few minutes with the original schematic from Jay_Diddy_B against the one I used to make my PCB routing and I really can't see anything that could prevent my circuit to work.
The DRC is fine and all the traces should go to the coorrect component.
In the silkscreen I privided, on top of the components you have the value of the components to place.
I'm not getting what it is wrong with the schematic or with the PCB and what it is mixed up in the components you have listed.

In few weeks I hope to have the spare time to build it and sort this out.

I have attached the comparison between the schematics.
Please let me know what I'm not seeing.
Thank you
Mauro
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on September 03, 2019, 11:30:13 am
it was the base connections were inverted think it was q4 q5 base connections were swapped,only spotted it as the board was thin and holding it up to the light i could trace the routing,hope that helps.
Title: Re: 5 Transistor ESR Meter Design
Post by: m3vuv on October 30, 2019, 04:20:38 am
seems to have died a death,still looking to use it with a 1ma fsd meter,any ideas how to do this?,cheers all m3vuv.