[Boatanchors] M-15 type microphone

[hwhall at compuserve.com]

I have a couple of questions about a microphone, a noise-cancelling type that looks much like a T-17 mike, that is labeled M-15/UR...

a) What was the period that the M-15 was in military service?

b) Has anyone ever disassembled the black carbon mike element part? I'd like to know how far I can take it down for cleaning without getting to a point the carbon grains might fall out.

Thanks!

Wayne
WB4OGM