Alternator noise in headset

[JonJay]

There is a relatively low volume, high pitch "whine" in my headset when I turn on the Alternator field. It is not percievable much of the time but is there. Any ideas?

[Ironflight]

Sounds to me like you've got a ground loop Jon. It could be many different things, but a quick one to check is to make sure that your headset jacks are isolated - not grounded - where they are attached. In general, audio line shields should only be grounded at the audio panel end, and you can get this whine if they are grounded at both ends. There are special fiber washers with a little shoulder to mount the jacks.

That's easy to check, and if it's not that....you'll be hunting ground loops for awhile!

Paul

[JonJay]

Originally Posted by Ironflight

Sounds to me like you've got a ground loop Jon. It could be many different things, but a quick one to check is to make sure that your headset jacks are isolated - not grounded - where they are attached. In general, audio line shields should only be grounded at the audio panel end, and you can get this whine if they are grounded at both ends. There are special fiber washers with a little shoulder to mount the jacks.

That's easy to check, and if it's not that....you'll be hunting ground loops for awhile!

Paul

Thanks. I will check it out. There is no audio panel. I have an SL30 and Flightcom Intercom. I used Van's intercom harness and followed those instructions but it could very well be grounded at both ends of the harness. Easy fix if it is.