I pull a lot of scraps off of old electronics and use the parts from them. I use to never grab capacitors that were unmarked on the boards. I was wondering if any one knew a way to test for the capacitance(farad rating) of them with out having to buy a whole new multimeter?
Thank you,
Hi there,
The method you choose would be based on what test equipment
you already have in your possession. If you have a multimeter that
also measures capacitance then you would use that, but if you have a
scope and a frequency generator then you could use that.
If you dont have any test equipment then you'll have to look for
markings on the cap body itself, and if you dont find any then it will
be impossible to find out without any test equipment so you would
at least have to buy a multimeter with a cap tester on it too.
These are not expensive anymore so you could find one for cheap.
If you also want to test inductors then you would need an LCR meter
instead, and that would allow you to test inductors and capacitors.
You could also buy a scope and frequency generator or build a
frequency generator yourself, but the LCR meter would be easier.
With a scope and generator there are quite a few methods you
could use to measure both capacitance and inductance.
One thing to keep in mind is that electrolytic caps are polarized, so
you have to take care of the polarity of the applied voltage when
testing.