This may be exactly what you are looking for, for the mic amplifier!

http://www.gfa.org.au/vic/mgc/micamp.htm

Stan

wrote:
Hello all,

I have searched and read the posted info on converting a military low
impedance headset for use in GA aircraft.

Does anyone have a schematic or have they actually built the lo - hi
impedance transformer and mic amplifer? I hate buying stuff I know I
could build.

Current pricing on the super secret powered amp is $79. It probably has
10 bucks of parts in it. I can follow a schematic or drawing and do
have experience building Cmoy power amps etc.

Thanks in advance for any responses.