Bizarre Intercom Problem

[Andy Young]

Was your cellphone charger plugged into power socket?
Still suspicious of the mike socket contacts!

No, it wasn't. Keep in mind that this has ben consistent, on EVERY flight over the last three years. I've never had a flight with this intercom in which this did not occur.

I looked at the mic sockets, as did the folks at Northern Lights. Also, it does it if I plug the copilot headset into pilot sockets or the rear sockets. It's dependent on where you're sitting, not where the headset is plugged in.

Thanks for the thoughts though, and please keep them coming!

[Wyflyer]

How about running it with the alternator turned off? The alternator is on that side of the engine, I'm now wondering if it could generate some RF.
Sounds like you have been very thorough.

[Andy Young]

How about running it with the alternator turned off? The alternator is on that side of the engine, I'm now wondering if it could generate some RF.
Sounds like you have been very thorough.

Yeah, tried that too. No change.
Thanks though.

[maules.com]

So do I understand correctly, wherever the copilots headset is plugged in you get the noise. Does'nt that point to the headset ?
Or is the noise only when two headsets are plugged in ?

[Andy Young]

So do I understand correctly, wherever the copilots headset is plugged in you get the noise. Does'nt that point to the headset ?
Or is the noise only when two headsets are plugged in ?

It would indeed point to the headset, and for years, I thought it was my girlfriend's Bose that was at fault. However, I have recently discovered that it also happens with every other headset I try in that seat, though it is much, much less prevalent with my particular headset.

In summation: It happens with any headset that is on the head of any person sitting in the passenger seat, regardless of what jacks that headset is plugged into.

[maules.com]

Have you sat there yourself?
Do you have the overhead or right side mounted speaker, or left side mounted?

[Andy Young]

Have you sat there yourself?
Do you have the overhead or right side mounted speaker, or left side mounted?

Yep, I've gone up alone, and swapped seat-to-seat. The problem occurs when I'm in the right seat, but not in the left seat. The speaker is overhead.

[maules.com]

What model Maule ?

[Andy Young]

What model Maule ?

1986 M-6-235 with the IO540W1A5D.

[maules.com]

Some models have the battery and master (full time) solenoid under the right seat. Some have a strobe power pack there, and some have Stec autopilot elevator drive.

[Andy Young]

Some models have the battery and master (full time) solenoid under the right seat. Some have a strobe power pack there, and some have Stec autopilot elevator drive.

Mine has nothing under the right seat. Strobe power packs are in the wing tips. No autopilot. It does have the (avionics?) relay under the right side of the panel; could that do it?

[maules.com]

That, I dont know. Anything is possible.
Try disconnecting the lighting rheostats maybe, also tyr disconnecting the speaker.

[Andy Young]

That, I dont know. Anything is possible.
Try disconnecting the lighting rheostats maybe, also tyr disconnecting the speaker.

Thanks Jeremy,

I'll try those. I did try turning the rheostats to see if that made a difference (it didn't) but I did not disconnect them.

[gbarrier]

Put the good black dog in the right front seat and the girlfriend in the back. Only works if dog doesn't wear headset.

[RobHill]

Ran into this once in a C182. It seemed that the air flow from the vent would break squelch and make noise when the boom mike was put in the stream of air flowing from the vent. It was the airflow which did it, rather than a person audible sound from the airflow. So, we figured that there was some sort of whistle being created at the boom mike as the air flowed past the boom mike.

Perhaps the ANR on your headset is particularly good.