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Old February 1st 09, 05:12 PM posted to rec.radio.amateur.boatanchors
Antonio Vernucci Antonio Vernucci is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 395
Default Carbon microphone revitalization

I have a NOS T-17 carbon microphone that I use with my BC.-191.

The modulation level is rather low, but I cannot easily determine whether the
problem is with the transmitter or with the microphone.

Two questions:

1) I have been told that carbon microphones can be revitalized by leaving them
in an oven for an hour or so at a temperature of about 180 F. Did anyone try to
do that? It would be easier to put the entire microphone in the oven rather than
just the capsule, but I am not sure on whether this could cause damages to the
non-metallic parts

2) I would like to test the microphone by measuring the output voltage with an
oscilloscope while talking. Does anyone have an idea on how much (peak) voltage
I should see on the scope when powering the microphone with 12 V, through a
resistor of known value?

Thanks & 73

Tony I0JX