Dual Dynon Com wiring to GMA340

[PYoder]

Installing two Dynon com’s - in a Bonanza with both a pilot PTT and co-pilot PTT and a Garmin audio panel. I’m assuming that both comms could be used simultaneously (although a rare event) with the 1/2 feature of the audio panel.
2 questions -
1, do we still use the ‘transmit interlock’ wires in the install manual?
2, does anyone happen to have a wiring diagram for this configuration? (Two Dynon comms to a GMA340)

thanks
Phil

 

[ebackscheider]

Installing two Dynon com’s - in a Bonanza with both a pilot PTT and co-pilot PTT and a Garmin audio panel. I’m assuming that both comms could be used simultaneously (although a rare event) with the 1/2 feature of the audio panel.
2 questions -
1, do we still use the ‘transmit interlock’ wires in the install manual?
2, does anyone happen to have a wiring diagram for this configuration? (Two Dynon comms to a GMA340)

thanks
Phil

Ever get an answer to this one Phil? Just installed my #2Com and I have the same question.

 

[Rhino]

Though Dynon and many others recommend using the transmit interlock, it isn't absolutely mandatory. If you don't have it though, you'll very likely get bleedover from one radio to the other on close frequencies. If the antennas are close to each other, that could easily become all frequencies. And if you both transmit on the same frequency at the same time, it might get very interesting, at both ends of the transmission. I'd personally just use the interlock, and not have both pilots transmit at the same time.

The two interlock wires just go between the radios, so wiring them is a piece of cake. On the SV-COM-760, T8 or T25 radios, the PTT input on each radio (pin 15) is jumpered to the TX INTERLOCK input on the other radio (pin 18).

 

[Rhino]

One caveat for clarity, though. The Dynon installation manual only mentions transmit interlock in the context of blocking audio "break-through". It doesn't specifically say it prevents the other radio from transmitting. But from everything I've seen, it does block radio transmissions, and not just audio.

 

[Rhino]

 

[ebackscheider]

Thanks Rhino, I added Pin18 while I was in there. I'll see how it works first, and add if it's a problem.