PS Engineering
PMA8000 Series Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-890-0000
Page 2-5
Revision 9, June 2005
2.4.11 Public Address Mode
By pressing the Mute and SPR pushbuttons at the same time, the PMA8000 will be placed into public ad-
dress (PA) mode. In this mode, both Com 1 and Com 2 receive indicators will blink, alerting the pilot that
when he presses his PTT switch he will be talking over the cockpit speaker. Copilot will still continue on
the selected COM radio.
When in the PA mode, J2 Pin 19 will go low, providing a digital logic level that can be used to incorporate
a speaker-switching scheme. This can control some switching means such as a relay that would transfer the
speaker output amplifier from the cockpit speaker to drive another cabin speaker. If the PA mode is used
with a microphone in proximity to an active cockpit speaker, feedback might result.
2.4.12 PA Mute (J2, Pin 12)
Pin 12 of J2 is a TTL logic output that is pulled low during PTT operation. This serves as an input to exter-
nal public address system to prevent feedback during transmissions.
2.4.13 Miscellaneous Logic Output (J2, Pin 18)
Pin 18 of the J2 connector is pulled to ground whenever the AUX button is depressed. This serves as a
control line for external devices, such as an entertainment system that the pilot wishes to control.
This pin can also be used to control passenger Karaoke Mode, by connecting to pin 13 of the J2, or as a PA
cockpit/cabin speaker relay control.
NOTE
: J2, Pin 18 should NOT be used
if
the AUX is going to be used to switch DME or auxiliary audio.
2.4.14 Intercom wiring
See Appendix C and D for intercom connection configurations. It is critical to the proper operation of this
system to have this connector wiring made in accordance with these diagrams. Use 2- and 3-conductor,
MIL-spec cable as shown. Connect the shields at the audio panel end only, and tie to the audio low inputs
as shown.
NOTE:
The intercom harness can be custom made by PS Engineering, Inc. Simply call the factory or
www.ps-engineering.com
to obtain a wire harness work sheet. The harness will be made to your specifica-
tions and fully functionally tested. Harness can be ordered with jack, or without the intercom jacks in-
stalled, for easier wire routing through the aircraft.
2.4.14.1
Entertainment Input
The PMA8000 has two INDEPENDENT music inputs. Entertainment input number 1 is J2 pins 23 (left
channel) and 24 (right channel), with respect to pin 25, and is provided to the pilot and copilot. Entertain-
ment number 2 is provided to the passengers at all times, and is connected to 26 (left channel), 27 (right
channel), with respect to 28.
Entertainment 1 and 2 must be connected together in order for all positions to hear the same music source.
We recommend installing a DPDT switch to allow isolation of the music source to the crew.
Ent. #1 Input
Alternate Music Interconnect
Note 7
Ent. #2 Input
24
23
25
27
26
28
