Transitor/ESR tester dead

[SteveNielsen]

Re: Transitor/ESR tester dead

The docs say say something about the ADC can't clock that fast. I think. Also states there a difference between using a sine wave and a square wave, the tester uses square wave.

[ben7]

Re: Transitor/ESR tester dead

The docs say say something about the ADC can't clock that fast. I think. Also states there a difference between using a sine wave and a square wave, the tester uses square wave.

Yep, you beat me to it.
It needs a faster ADC so it can capture the waveform, then calculate the ESR based on voltages and time (I think XD).
Of course, it could possibly do it with some external circuitry to trigger the ADC when it needs to measure a certain part of the waveform.

-Ben

[SteveNielsen]

Re: Transitor/ESR tester dead

Yep, you beat me to it.
It needs a faster ADC so it can capture the waveform, then calculate the ESR based on voltages and time (I think XD).
Of course, it could possibly do it with some external circuitry to trigger the ADC when it needs to measure a certain part of the waveform.

-Ben

Yeah, also something about it taking 1.5 clock cycles of the ADC after the charge is applied and in that time the charge is already decaying in the cap under test. I've been looking at the documentation a bit lately.

I don't know if ext ckt could speed up the process. I don't know enough about these chips but starting to learn a bit.

Random thought - what if they could make this thing into a little o-scope? It'd need better graphics but that'd be fun

[ben7]

Re: Transitor/ESR tester dead

Random thought - what if they could make this thing into a little o-scope? It'd need better graphics but that'd be fun

Oh, plenty of people have done that! Not very good performance, but hey, it can at least give you an idea as to what a signal looks like!


-Ben

[SteveNielsen]

Re: Transitor/ESR tester dead

Really? Got links? Yeah, that's all you could expect but an imperfect measurement gives more information than none at all.

[stj]

Re: Transitor/ESR tester dead

all over ebay.

btw, you could maybe add an SPI interfaced flash ADC chip.

[vinceroger69]

Re: Transitor/ESR tester dead

http://www.ebay.co.uk/itm/DSO138-2-4...8AAOSw9r1WA5ep

[SteveNielsen]

Re: Transitor/ESR tester dead

STJ: Do you have wiring diag of the 10 - 6 pin adapter?

[stj]

Re: Transitor/ESR tester dead

yes

attached:
the common programmer,
the standard header pinouts,

and pics of an adapter from ebay - that i dont own btw, just saved the pics.

[stj]

Re: Transitor/ESR tester dead

btw, put something over the display before you solder a header on, so you dont get flux on the panel!

[SteveNielsen]

Re: Transitor/ESR tester dead

Ok. Will do. Finally ordered the rotary and programmer. I'll scrounge up stuff for the connections. Thanks.