PTT switch - how does it work?

[Guest]

I bought a Push-to-talk switch thinking it would be cool to use my Avcomm headset for online ATC. I spent the morning putting together the circuitry needed to convert the mic impedence and it all works EXCEPT the mike is live all the time. I somehow envisioned the PTT switch as a simple switch that made the connection between the mic and the transmitter but that doesn't seem to be the case. I can probably gut the thing and somehow make a simple switch out of it but I'm thinking there must be a more elegant solution - if only I knew how such things work. Does anyone know? Thanks!David

[LAdamson 240]

Since I have to deal with this shortly for my PTT buttons on both the joystick and panel for my full size plane, I typed in Push to Talk Switch. There are a number of web sites to look at that may help. I already have an audio panel, but havn't checked the wiring diagram yet. Here is one of the sights with a diagramhttp://morrowmarsh.ca/concours/techpages/pttbasic.htmThis one might even be better --- diagram wisehttp://www.aeroelectric.com/articles/micjack/micjack.html

[Guest]

Wow! Thanks for the great links! I tried a web search too but all I got was a bunch of ham radio stuff. Your links definitely helped. It didn't occur to me going into this that the PTT actually signals the transceiver directly through its own wire. To make it functional for my use, then, required some alteration. I opened the jack on the PTT and altered the switch component so it is now in serial with the transmitting circuit. I also considered leaving it wired as is and using the PTT wire to trigger a keypress that would activate transmission on Roger Wilco but the way I did it seems more flexible. Granted, I can never use it in a real plane now but it was a cheapy I bought online for this purpose anyways. I used my Avcomms on a Vatsim flight last night and it was great! Only problem is my wife can't talk to me when I'm simming now. On second thought, maybe that isn't such a problem... ;-)David