Is Configuration of Com Monitor Audio Required?

I had my avionics shop add the Comm Monitor lines from the IFD540 to my PS Engineering PMA8000.  I specified connecting to the DME audio inputs, which means the audio should be selected by the "Aux" button, and which also matches the wiring of the special "Avidyne" version of the PMA8000.

Alas, it does not work.  My test was simply to tune the local ATIS, and confirming I could hear it with ATIS as the Selected Comm frequency, swap the frequency with the Aux input selected.  No audio.  On the Sys->Audio screen, the Monitor audio is mid-range (and I tried increasing it, to no avail.)  I also had them add the wiring of Alerts (to the "ADF" button, "A" for "Alert" ), and that function does seem to work.

Today I talked to Avidyne support, and they confirmed that the HW mod to support the "Monitor" audio was performed when I shipped it back for SB work in May or June of last year.  So...

Is there any configuration item on either the Sys or Maintenance screens besides the volume for the Comm Monitor function?  I didn't find anything in either the Pilot's Guide or Installation Manual, but my search could certainly be inadequate.  Tech Support was ambivalent beyond "the standby block should show that your are receiving", something I can readily check, and will.

I'm going to meet with the installer at the airport tomorrow, and it would be good to have available any additional knowledge.  They've confirmed the wiring with an Ohmmeter (IFD pins to PMA pins; I'll ask tomorrow if they confirmed the Hi pins weren't also shorted to ground.)

Thanks in advance!

Jon

I specified connecting to the DME audio inputs, which means the audio should be selected by the "Aux" button

I am not that familiar with the PMA8000, but wouldn't it be the DME button to select the DME input?

David Bunin

DavidBunin wrote: I specified connecting to the DME audio inputs, which means the audio should be selected by the "Aux" button I am not that familiar with the PMA8000, but wouldn't it be the DME button to select the DME input? David Bunin

Edited by oskrypuch - 01 Mar 2016 at 11:01am

We wired our standby freq monitor to the former ADF button ( and relabeled it) on our PMA 8000bt. We still have a DME and is wired separately.

I Also remember reading that only the second freq box can be used for the monitor function.



Edited by Dlesh123 - 01 Mar 2016 at 7:56pm

AzAv8r wrote: The PMA8000BT "Installation and Operators Manual" states in numerous places, including both in the Operations section and on the interconnect diagram: "DME audio is passed when AUX button is pressed."   That is in addition to "Aux" audio.  Eg, the two inputs on the back are not differentiable on the front. Go figure.   Now, the manual might be wrong, but there certainly is no other mechanism obvious for the Operator (that would be me) to select the source connected to the DME input.

I did not find any mention of such in the PS Engineering manual.  One of the unswitched inputs has a volume adjust, but it's an installation-time control, accessed through the bottom of the unit.