PMA7000 compatability

[M20S Driver]

Hello,

 

I have  a PMA7000 in my Eagle and use two Bose ANRs for the front seats.  I have two older Sigtronics for the rear passengers but they only work if I plug then in the front jacks for pilot and co-pilot..  If I plug-in the two Bose headsets in the rear seats and the older Sigtronics in the front, all four will work fine.  

 

Does anyone have any idea what is causing this and if it has any solution short of buying two more Bose headsets?

 

Thanks for your help

Masoud

[N601RX]

Do they have a stereo /mono switch?

[Cris]

Masoud Go to the PS engineering site and download the install manual for the 7000 m-s which will give you the check out procedures to verify all is working not to mention the wiring diagram. In addition you might borrow a different headset to see if that makes a difference. The stereo mono switch previously mentioned is a good possibility. You can check that easily by changing it on your Bose. I am assuming that the Sigtronics are only mono headsets. The ps 7000 can be easily modified to cure that issue if you want to keep the headsets but I've seen new off brand ANR headsets for as low as $200 ea.

[kevinw]

I have a similar setup in my J; PMA7000 with Bose ANRs (6-pin) in front and 2-pin connections for the rear passengers. I use some old David Clarks in the rear and never had a problem. Try using a different mono headset in the back to rule out your Sigtronics.

[N201MKTurbo]

I assume the mics all work and you are just not getting any audio to the headset speakers. Try pulling the headset plugs (the fat ones) out one notch (about 1/4 inch) in the back.

[Jerry 5TJ]

Hypothesis:  If all four jacks in the plane are wired for Stereo and if L and R are reversed on one of the rear plugs, and if you plug in a pair of mono headsets with the 2 contact phone plug it is possible the L and R are each hooked to ground and so the two mono headsets will basically short each other out when used in the rear.  Both rear seats share the same audio out towards the headsets.   In the front the pilot and copilot are on different audio circuits to each headset.   If this is happening, then ONE mono headset should work in the rear but not both at the same time.  Borrow some stereo headsets and try them; all four should work in that case.

[M20S Driver]

Thanks for all the posts. I will test the mono/stereo and wiring checks this weekend and report back.

Clarification: With Sigtronics in the back jacks, the speaker or mike plugged in separately don't work. One or two Sigtronics in the back does not make any difference and they don't do anything plugged in the rear jacks.

[M20S Driver]

Today, I tested the Mono/Stereo scenarios with no luck.  The wiring looks the same on both sides so I assume it should be OK. I also noticed that the Sigtronics headset's speaker works in the back but the volume is so low  that is hard to hear.  The Mic is completely off.  

 

My last shot is to try a couple of different headsets in the back (David Clark?)  and if that doesn't help, buy a couple of more modern ANRs for the back seat.