Thanks but here is more info.
I was trying wrong. I was trying to shut down the mic at the mixer out but I think it has to be shut off at the radio plug by not sending a carrier. I'm running a shure mic 58, no switch, into a mixer which has a 2 wire main coming out. I do know my pin set up at the radio is pin 1 shield, pin 3 is transmit and 2 is audio pin 4 recieve. By shorting 1 and 3, at the radio, I throw a carrier. It looks like I need center out of mixer to go to pin 2 the ground to pin 1 and a second ground switchable, on off, with foot switch to go to pin 3. If this is right I need 3 wires coming out of my box which means one jack needs to go to let a 3 wire cable go to the radio 4 pin plug. Am I close??? Thanks Ron
Take a close look at the schematic for the microphone to see how the leaf switch is wired. On a typical radio (modern) they're double pole / double throw. One side shorts the mic element (mute) until the PTT is closed, then the mic opens up for TX. Some will also mute and un-mute the speaker. On the other side of the switch the center pole toggles between "enable RX" and "enable TX". In older radios with a T/R relay the normal state was RX until the PTT kicked the relay to TX. On electronically switched radios the PTT may always be needed to turn on TX or turn on RX.
If the radio won't play without the mic plugged in the PTT is muting the speaker as well as the mic element, or the radio wasn't designed to assume RX when the mic is "normally open".