SonexBuilders.net

Am getting static only while talking. If I push ptt switch without talking I get no static. Noticed the wires to the jacks are not shielded so I'm guessing that's a no no. So just to confirm, are the wires to the jacks supposed to be shielded?

John

The Flightcom installation manual says to use shielded wire on all mic and headphone lines so that would be a good start.

Peter

I don't remember what my installation manual said, but I would definitely shield those wires. I did.

I have run into these kind of problems on a few others aircraft installs, and one thing is to definately use shielded wires, grounded at one end only, a the radio ground point, as close to the radio chassis as you can, typically a screw on the radio itself, or the main ground wire into the radio. Further, the jacks, where the headset/ mic are located, typically on a metal surface, you really should use insulating washers ( plastic, fiber or bakalite ones) with a pronounced collar that keeps the jack totally insulated from the mounting metal, preventing a ground loop in the audio, for both the head set and mic circuits. I believe ACS sells them. Run the shield all the way to the jack, and connect the shield to the ground post on the jack, not to anything else,other than to the other end at the radio itself. I also had to put quite a large capacitor on the dc buss, under the pannel, to prevent any engine noise interfeering with the audio, either inbound or outbound via the radio. Best of luck!!

Johns wrote:Am getting static only while talking. If I push ptt switch without talking I get no static. Noticed the wires to the jacks are not shielded so I'm guessing that's a no no. So just to confirm, are the wires to the jacks supposed to be shielded?

John

Yes, those wires should be shielded.

However, the first test I'd run is to use another headset. Fast, easy to do and eliminates that possibility.

Joe, great info,thanks for that!! Will definitley check and do all that I need to.

I have swtched headsets.
, I have a Lightspeed anr pair, and The quiet technologies Halo TubePhones. I actually prefer the Halo TubePhones better.

Thanks Guys!! John