Cobra 29 LTD Classic - microphone circuit?

[KK4JW]

Cobra 29 LTD Classic with an Astatic 636L. I understand the 636L is a noise cancelling microphone and will result in lower audio drive, so how can I adjust for this? Are there any components in the mic amp circuit that I can swap out to boost drive a little bit?

Thanks!
73

 

[DoctorAudio]

Change R67 next to TR17 to a 15 ohm, 1/2 watt. (or 1/4 watt if a newer board)
R67 determines the gain of the bootstrap of the mic amp circuit. Lower the value the higher the gain.