EEVblog Electronics Community Forum

Products => Test Equipment => Topic started by: Steve Zarg on June 20, 2014, 01:45:33 am

Title: I'd like to test a microphone capsule's capacitance: 50-100pF.
Post by: Steve Zarg on June 20, 2014, 01:45:33 am
Hi,
 I've been working on a condenser microphone project and I have been trouble shooting an issue with the impedance conversion circuit that accompanies the capsule.

 I need to reassure myself that the capsule is still working correctly and so I'd like to measure it's capacitance, but my Fluke 179 DVM doesn't have a range that will test for such a small value.

 If the capsule is undamaged it should read approximately 70pF.

 I just searched the forum and got caught up looking at LCR meters, and watching Dave's tear down and review videos.

 I'm thinking that I'm over thinking this. Can I make accurate measurements with a cheap store bought capacitor meter or will I end up learning I need something hi end? I learned about, but don't want to pursue, the idea that I can build a cap meter from a kit. I prefer to buy something so I can keep tinkering with the microphones.

 I think I learned enough about the LCR meters Dave reviewed to make a decision about something expensive, but I've also seen a few simple "Capacitance Meters" for under $100 that seem to have a range that will measure pF.

 I got over whelmed reading and watching... any tips?

 Thank You.


 BTW it seems like a happy coincidence that several of the recent blogs have been about the type of microphones I have been working on. I just discovered them this evening. Thanks Dave!