For what it is worth, I got rid of the big spike by making two changes.
First, there was a 2.2K resistor in the power line leading to the mic
element. This resistor is between the PTT switch and the element so I
increased that to 22K. I tested it with a resistor substitution box and
the mic output was unchanged until the resistor value got to about 33K.
At 22K, the output level is the same as before so it is not too much
Secondly, there is a capacitor from the positive terminal of the mic
element to ground. I added extra capacitance at that point and those
two changes got rid of the spike completely. My theory was to prevent a
voltage spike from being supplied to the mic element. So, between the
larger resistor and the larger cap, it allows the voltage to build up
quickly instead of being a sudden power spike. The audio output level
is the same as before the changes and the audio quality also seems
unaffected to me.
Just thought I would post what I did. It was spiking to 100W every time
I keyed the mic before the fix. I'm not sure why but I'm happy with it now.
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