Geek wrote:
Hi and welcome!
What I see here is a circuit that shorts the AC and the DC difference that causes the *pop* is bled-out by the 100K resistor.
How well 100uF will work depends on the output imedance of the microphone. IIRC, most electret condensor built-in preamps are about 47 to 100 ohms. So you'll need 10 ohms or less reactance at the lowest frequency. For voice communications on a talkie, this is usually cutoff at 300Hz. Use 100Hz for good measure.
A quick check on a reactance calculator says 220uF will work.
This isn't a HiFi circuit, so best linearity isn't needed, but low ESR on the cap is. A Panasonic FM series would be my first go-to.
If the leakage is too much and you still get a *pop* after cap break-in period (~50 hours), my second go-to would be a Nichicon UKL low leakage.
Cheers!
Thanks for the reply! So the issue is not with this circuit - it works fine as it is with a NC switch.
I need it to work with a NO switch somehow
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