If this is the amplified T-UG8 mike, you'll find a tiny slide switch on the battery bracket underneath. It should be set to the "E" side, not the "R" side.
There should be some of the original mike cord still soldered to the connections under the radio's chassis.
The stock mike should have had a red and black wire. The audio is a white shielded wire.
White and shield go just where they did on the old mike cord.
But red and black get reversed.
Johnson used red for receive. Astatic uses black for receive, and red for transmit.
And if there is no trace of the original mike's wires, that makes it more complicated.
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