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Ringway Flyer
5th Mar 2010, 15:11
I have a 10 year old Sigtronics headset, which has, so far, worked fine. However last time we flew, I had bad radio reports. When challenged, i was told that the carrier was fine, but the audio was very weak. Since it was a bit busy, no further tests were carried out.

The intercom is a Garmin GMA 340 and the radios are Garmin GNS 430s. The headset is the basic, mono, non noise cancelling type.

I intend to try a few variations and see if the problem can be isolated. The comms between P1 and P2 are fine. But I will try using the P2 sockets with the same headset, and both with my second, identical but rarely used headset. And also try the other radio.

It's possible that the problem has been there all the time, but not bad enough to make communicating a problem. I can see no way to change the impedance via the intercom, if that's an issue, and have had no reports in the past of audio issues. It's been used in two other PA28s and several PA38s without any comments. :hmm:

Any suggestions?

RF

GarageYears
5th Mar 2010, 16:50
I think you need to try the other checks you already mentioned before it is possible to know if the problem is in the headset itself or the radio. Particularly using the suspect headset in the P2 side, and the P2 headset in the P1 side, and the other radio. Since you state that comm between P1-P2 is OK, that steers me to think it is not the headset, but the other tests will prove that.

- GY

Ringway Flyer
6th Mar 2010, 06:26
Thanks, GY, we hope to carry out the tests today. I'll put the results on here for the benefit of anyone else who might have a problem.
RF.

Ringway Flyer
6th Mar 2010, 16:57
Well that didn't take long.... RTFM applies, here. The manual for the headset emphasises that it is very important to ensure that the mic is 1/4" from the corner of the mouth. Using both headsets, we each spoke to the tower, being very careful regarding the mic position. Perfect transmissions. We then experimented in the cockpit only, and only a very small deviation from the correct position knocks the audio level down a lot. Whilst it was still quite acceptable in the cockpit, it obviously wasn't in a noisier environment without headsets.....

:O