"Scott VanHoveln" wrote in message
...
I need to know how to make a headset converter that allows me to use my
military (low impedance mic, single plug) headset in a GA airplane. The
plug pinouts I can probably figure out, but the mic impedance matching has
me stumped.

Jim will give a more useable answer,
but here goes for what it's worth:

There's more issues than impedance.
Standard airborne equipment is still ridicilously
designed for the carbon microphone of the 1930's or so,
it feeds a DC bias into the microphone jack
which is unhealthy to dynamic mike cells.

Do you know how your headset mike works?
If it is dynamic, some kind of adapter will be required.
If it is (as I suppose, because that's state of the art)
a condenser type with the required preamp,
it has a fair chance of needing only an adapter plug.

Just on a theoretic sidenote:
if impedance matching is the real issue,
a transformer is the answer.

Good luck!