DC Headset problem

[cabzjet]

I have a David clark H10-13.4. It is about 6 years old and i have had no problems with it until now.
I recently started flying a Decathlon.
My headset works fine in all other aircraft(so far) But in the Decathlon when i transmit on the comm there is a very loud squealing sound and my readability is about 3. The pilot to pilot intercom works fine, and only occurs in this aircraft. I have tried other headsets and they work fine. including another DC H10-13.4.
Any ideas on what might cause this? Or how to fix it? I do not want to buy another headset just for one aircraft.

[hiwaytohell]

I had a similar problem occurred when the other headset was a different type.

With two DC H10-30s no problem, but when we plugged in a different type similar problem.

[ampclamp]

Sounds like feedback. Unplug other headsets and turn down any volume on any speakers . see if it persists.If gone, plug in another headset, again with its vol right down, see what happens, gradually turn up volume to see if and when the squeal returns. The fact it just happens on one headset maybe just a mic sensitivity setting on the headset (assuming it has one) or perhaps the sidetone level thru the comm getting back into the system.
When you say comm, assuming you mean normal VHF comms ?

[baswell]

I have heard of similar difficulties with sidetone on some intercom and headset combos. Are you flying solo, or with someone in the back? Unplug their headset to see if that is causing the issue.

[Metro man]

The headset may be incompatible with the avionics fitted. In the Airbus we have to get company approval before using personal headsets, there is a list of models which aren't approved. Many of these are from the major manufacturers.

[gerry111]

I bought my DC H10-13.4 headset back in 1998. It worked fine for me for several years in Cessnas, Pipers and Bonanzas. That was up until I loaned it to a non pilot friend who was a passenger on a SeaRey delivery flight from YSBK to YGLB. The selling pilot complained that the intercom mic audio/ sidetone was broken and blamed my headset. (Like an intermittent connection.)
So I then sourced a new cord assembly from the Pilots' shop at YSBK and replaced it. Quite a difficult job as all the connections need to be soldered and heatshrunk. That's a fiddly job even for an electronics technician of 37 years experience that I am.
I subsequently flew in the SeaRey and the DC has performed perfectly ever since. That was several years ago. So I'm unsure whether I really identified a problem or indeed fixed it...

My suggestion Cabzjet, is to buy an Altronics DC inexpensive clone headset and see what happens with that.

[truthinbeer]

I bought a DC ANR headset 2nd hand online. It had an intermittent interference problem in the flying school's Warrior. Disappointed I contacted DC in US who advised me to take it to Pacific Avionics the DC repair agent in Bankstown. They replaced the twin plug section of the cable under warranty! Send an email to DC in US and ask their advice. Their willingness to help and the great service from Pacific Avionics might surprise you...it did me.

Cleaning the plugs may be all that is required. Use electrical contact cleaner or if not available nail polish remover, surgical spirit from the chemist. Dampen some kitchen towel and give the plugs a good rub. If that doesn't work go back to plan A, David Clark really do look after their customers. I cannot speak highly enough of DC and Pacific Avionics.

[cabzjet]

Thanks for all the replies. I have been dual and had the other pilot swap headsets as well. I will try and clean the plugs and see what happens, failing that a new cable.
Thanks

[scroogee]

You might also try moving the cords around if you can. I fly one aircraft with a removable PTT that gives a squeal if it runs under my leg from the control column to the (side mounted) radios. If I put it over my leg no problem.

[gerry111]

The new cord assembly I fitted to my DC had plated mic jack and phones plugs. (As opposed to the brass originals which hail from the 1940's or earlier telephone exchanges.)
So I rather doubt that corrosion of the plugs will ever be an issue no matter how infrequently I fly. I'm guessing that your headset has the same type of cord?

[scrufflefish]

I used to get some squealing from the Gosport tube in the DH82, but only during aerobatics.