THURSTON ACKERMAN wrote in a message to ROY J. TELLASON:

TA> I just wondered if it might be a PUSH to Talk mike like we useto 
TA> use on mobile transcivers. If I recall correctly it was the tip and 
TA> ground ring contact useta switch the transmitter ON when Pushed to 
TA> close the circuit.

TA> 10-4 ?

Well,  this one has a little slide-type switch on the mic body,  to turn it
on and off.  Paid something like $6 for this at a computer show a bunch of
years back.

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