ESR meter upgrades

[stj]

Re: ESR meter upgrades

you need firmware that matches the crystal speed because there are time-constants in the software.

[eccerr0r]

Re: ESR meter upgrades

Ah so the actual value doesn't matter and you don't need to "enter" the value in...? interesting. I guess with accurate "T" and "R" you can still find accurate "C".

Will be interesting to compare this to the Sencore.

[redwire]

Re: ESR meter upgrades

If the crystal does not match the MCU fuse setting, as well as the F/W- there are problems. Fast F/W with low crystal will read smaller C values I think.
i.e. compiled F/W build is for 20MHz, crystal fuse 8MHz, C readings too low.

TransistorTester with AVR microcontroller and a little more
Version 1.13k Karl-Heinz Kubbeler

[stj]

Re: ESR meter upgrades

a copy/paste from my old txt

after programming, you need to calibrate the unit. (preferably twice)
you need something to short all 3 inputs,
and an accurate capacitor between 100n and 1uf - i recommend a 220n polyester cap.
-
you also need a good stable capacitor between 10 and 30nF to calibrate the new small inductor mode.
if you dont have one, just ignore the cal message till it times-out

[eccerr0r]

Re: ESR meter upgrades

How much calibration do these need anyway, these devices vary so much that we need 0.1% capacitors to calibrate them? Uhoh.

2uF capacitor? (I've hated "mF" for uF even though they've done this in the past, grr. I don't like mmf for pf either. Make Money Fast!)

0.022uF = 22nF = 22000pF = 22 x 10³ pF = code 223; 223j = 0.022uF±5%

I don't think I have any accurate (i.e. not a ceramic) 0.22uF capacitor... needed for calibration?

[sauna]

Re: ESR meter upgrades

I will explain the test.what it should be.


1. in the first stage, short circuit to 123
2. the second stage I have a 2 mf capacitor
3 .0.022 capacitor.this is 223j.this is 23nf
or am I wrong?

[sauna]

Re: ESR meter upgrades

Thank you, stj.I've tried everything.at the last stage, he does not measure anything.
as if stuck tightly.

[stj]

Re: ESR meter upgrades

223 is 22nF
you need 220nF (224)

[sauna]

Re: ESR meter upgrades

https://disk.yandex.ru/d/EWk4K3zB3bKl9w

Hello.I have such Mega328 V 2,68 ESR-T4.

https://de.aliexpress.com/item/10050...3bce0dd330da5b

after the modified firmware I can not go self test at the last stage.as if stuck.for 1 and 3 times I tried a new 223j capacitor. This is the last stage of verification.I have already stitched 30 different firmwares with many firmwares. But alas, I can not pass the test. At the last stage, I did not save my own. It's a pity.

[redwire]

Re: ESR meter upgrades

I think Schottky leakage current is much higher.
I tried a 1N459A silicon low leakage diode and Vf=761mV but no Ir measurement shows up on the display.

[eccerr0r]

Re: ESR meter upgrades

Hmm so it looks like it might sort of distinguish a germanium compared to a schottky actually... but it can't do it directly at least as of yet...

[redwire]

Re: ESR meter upgrades

I have a bunch of germanium diodes tried out, and not so impressed. Readings seem to be different every run. AY-AT and stj's F/W I think 20MHz:

1N34A 371mV (DMM measures 317mV)
1.6pF--1.2pF @0-5V
Ir=74nA

1N34A 376mV (DMM measures 317mV)
1.8pF--1.2pF @0-5V
Ir=61nA

1N54 848mV (DMM measures 470mV)
27pF--17pF @0-5V
Ir=5.1uA

1N54 846mV (DMM measures 482mV)
11pF--10pF @0-5V
Ir=2.4uA

1N34A 380mV (DMM measures 313mV)
1.7pF--0.72pF @0-5V
Ir=46nA

[stj]

Re: ESR meter upgrades

no, not seen one since i was small and had a radio-shack crystal radio kit!!!

[eccerr0r]

Re: ESR meter upgrades

hmm... I guess we'll find out regardless, provided it ships...

If you're curious now, do you have any germanium transistors and just stick in two terminals?

[stj]

Re: ESR meter upgrades

if i had a germanium diode i could tell you

[eccerr0r]

Re: ESR meter upgrades

speaking of which... can it tell the difference between a Schottky diode vs Germanium?

[stj]

Re: ESR meter upgrades

well the tc-1 uses a 44pin atmega324,
and there is a highland one with an atmega644

probably others too

[eccerr0r]

Re: ESR meter upgrades

oh well pulled trigger on one, unfortunately it's a 32K flash limit, but nevertheless it still should work to test parts even if it cant take latest flash...

just hope it knows how to detect germanium transistors/diodes and I couldn't care less if it could PWM or be a frequency generator, I have other tools for those functionalities...

[clearchris]

Re: ESR meter upgrades

i have no idea - first time i'v seen that.
it looks similar to the one we call "AY-AT"

if your thinking of buying it - dont.
it has a 32pin cpu - so limited to 32k flash.
you want one with a 44pin cpu so you can use upto 128k for maximum features.

Do you have a suggested unit you like? It's time for me to get one of these...

[eccerr0r]

Re: ESR meter upgrades

How widespread are the "44 pin" units? Which specific microcontrollers qualify for these? Seen any specific models with them?

Since it seems that there are so many mega328 units out there, wouldn't it make sense to keep trying to use these?

Dang. I would rip out the PWM generator code, rather have a dedicated device to generate PWM and not sacrifice this unit to control something. Frequency counter... maybe keep. Signal generator... rip out, same issue/opinion as PWM code. *shrug* again just IMHO...