I've got a PS Engineering PM2000 intercom, a King KMA24 audio panel, a Garmin GNC355 gps/comm, and a Garmin SL60 gps/comm that I'm installing in the RV7 I'm building. All of the radios are used except for the GNC355. The intercom works fine between the pilot and copilot, PTT works, too. I can hear audio coming back through the audio panel and intercom from the gps/comm radios and it seems fine. The problem is that when I use the PTT, instead of my voice being transmitted I get a tone (200 hz, I'm guessing) and no intelligible voice. I suspect I have a wiring screw-up on the mic side, but am unsure where to look.
Any help is appreciated!
Any help is appreciated!