Clicking in headset

[jd21476]

I just had a Garmin GNC355 with GMU11 and GAD29b installed along with a G5. I previously had a Garmin 330 transponder but it is not an ES model.

anyway, my avionics guy called me today as he was testing the new install and asked if I had previously had a clicking in the headset, which I did not. He said he seemed to have isolated it down the the transponder but cant seem to get it to stop.

He describes it as a repetitive clicking noise. Any ideas?

 

[Ryan Klems]

Bose headset? I’ve heard this pretty commonly with the Bose headsets and any 1090ES transponder. It’s very quiet and I’ve never really been able to hear it once things get a bit noisier (engine running).

 

[Jesse Saint]

If it’s about once per second, I’ve seen that before with an unshielded RS232 signal too close to audio wires.

 

[Rcmutz]

Once per second sounds almost like the flashing beacon. Could it be the that or strobes? Make sure it is not either of them causing the issue.

 

[jd21476]

Bose headset? I’ve heard this pretty commonly with the Bose headsets and any 1090ES transponder. It’s very quiet and I’ve never really been able to hear it once things get a bit noisier (engine running).

This was tested with a David Clark headset although I do use a Bose

 

[RickC]

when I had my GPS installed and I got the plane back there was clicking in the headset. I traced it to the interrogation light on the transponder. When it lights up I get a click. It's very faint and doesn't bother me but it was irritating at first not knowing what it was.

 

[jd21476]

That sounds like what it would be. How do I get rid of it?

 

[RickC]

The avionics guy said that it was probably the connector in the back of the transponder. Since it works and hasn't been a bother I just let it go for now.

 

[bkspero]

when I had my GPS installed and I got the plane back there was clicking in the headset. I traced it to the interrogation light on the transponder. When it lights up I get a click. It's very faint and doesn't bother me but it was irritating at first not knowing what it was.

I've had this type of clicking in the headset and it also correlated with interrogation of the transponder. In the case of my plane the issue, though, was the connection between the transponder antenna and its coaxial cable. Removing the cable and a shot of Deoxit contact cleaner, a sign-off, and restored peace and quiet.