OK, so my pretty exhaustive search for a replacement hand mike for my Vigil RT-80 VHF
turned up nothing. On to plan B....
I bought a new ICOM
HM-100N hand mike that I figured I could make work. It's a basic condenser mike... or so I thought.
The OLD mike was 4 wires, and the electrical engineer
who was the P.O. of the boat (seriously - he was an electrical engineer
...) had done a drunken soldering job of the 2 wires that are apparently the only ones needed for this thing to work. 4 wires, red, black, yellow & shield of which only the yellow & shield were in use. I swear it worked - just the bakelite case is busted up from being dropped on the deck
The picture tries to show that the yellow wire goes first to the PTT switch, then to the condenser, then out of the condenser via the white wire which is then soldered to the shield. Easy enough to figure out - a nice little loop controlled by the push to talk switch.
The NEW mike is an 8-wire setup
I see from the schematic that Pin 4 is the PTT switch, Pin 6 goes to the condenser, and Pin 7 is ground.
So, how do I wire this to create the same "loop" configuration of the old microphone? Since the ground is common to both the PTT switch and the condenser, I can't just take the PTT output and feed it into the condenser can I?
Any suggestions would be appreciated.