[ARC5] T-30 throat microphone

[Robert Eleazer]

Back in the mid-70's I got a T-30, plugged it into the stock PTT switch that matched it and gave it to a friend to try out in his airplane.  He got signal reports back that his voice was garbled.  Aside from that, he said he just knew that if the airplane crashed he would be trapped by that strap around his neck.

But I do recall hearing that after WWII skin divers rigged up a simple comm system using the T-30 plus a battery and a dynamic speaker and found they could talk to the surface.  Of course, the throat mike did not require that they remove the SCUBA mouthpiece.

What kind of adapter was employed for the tests?  I built some mikes for use with headsets in airplanes using a Radio Shack electic mike plus a transistor and a few other parts.  They worked great although they were not noise canceling and thus could not be used with an intercom. 

Wayne