motorola desk mike to Kenwood radio need help

[anautofix]

Hi all, I am trying to rewire a Motorola desk microphone to a Kenwood TK-8180. The issue I am having is how to get the needed voltage to the microphone. I know which pin from the Kenwood supplies voltage, but cannot seem to find where the microphone accepts it. Any help is greatly appreciated.


Thx. and a Happy New Year to all.

[Jim202]

Hi all, I am trying to rewire a Motorola desk microphone to a Kenwood TK-8180. The issue I am having is how to get the needed voltage to the microphone. I know which pin from the Kenwood supplies voltage, but cannot seem to find where the microphone accepts it. Any help is greatly appreciated.


Thx. and a Happy New Year to all.

Motorola has the DC bias on the mic high line. You would have to use a cap at the radio to keep the DC bias voltage off of the mic high input. Then use a resistor to add the DC bias voltage on the mic side of the capacitor. You might have to play a little with the value of the resistor, depending on what source you use for the bias.

If you modify the circuit behind the mic connector inside the radio, then a normal Kenwood mic would no longer work.

Jim

[Will]

Same basic interface as I use on an ICOM7100 HF radio... two resistors...