PS Engineering
PAC45J Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-045-2000
Page 2-16
November 2020
Regardless of the position of Switches 43, 44, or 45, the Pilot will always hear music, if present, and Switch
42 controls the muting behavior.
2.7.11.1 Music Mute
When Switch 42 is
ON
, any music playing will mute when intercom or radio communication is active.
When Switch 42 is
OFF
, the music will NOT mute when
intercom
audio is present. It will mute for any
radio
activity.
2.7.11.2 Copilot Music Enable
When Switch 43 is
ON
, the copilot position will hear music that is present
When Switch 43 is
OFF
, the copilot position will never hear music in the system.
2.7.11.3 Observer Music Enable
When Switch 44 is
ON
, the observer 1 position will hear music that is present
When Switch 44 is
OFF
, the observer 1 position will never hear music in the system.
When Switch 45 is
ON
, the observer 2 position will hear music that is present
When Switch 45 is
OFF
, the observer 2 position will never hear music in the system.
2.7.12 Speaker Alert Audio
When Switch 46 is
ON
, the internal audio alert audio messages will be presented to the cockpit speaker.
When Switch 46 is
OFF
, the internal audio alert audio messages never be heard over the cockpit speaker.
2.7.13 Backlight Dimmer Voltage
Switches 47 and 48 control the backlight dimming input expected for the purpose of adjusting the curve.
For 28 VDC backlighting both Switches 47 and 48 are
ON
.
For 14 VDC backlighting, Switch 47 is
OFF
and 48 is
ON
.
For 5 VDC backlighting, both Switches 47 and 48 are
OFF
2.7.14 Other Shared Functions
Some functions are set by switches not easily accessible to the installer. Contact PS Engineering for detailed
information.
These include:
•
Observer 1 CVR or Observer 1 Speaker output (J452-39)
•
Observer 2 CVR or Copilot Speaker output (J452-40)
•
J455 function as Observer 2 or Pilot Control Head port (Shipped as Observer 2, pilot on J454)
•
Hand Mic enable for Copilot (J452-57) and Observer 1 (J452-58) (eliminate Unswitched 5 input
and wired telephone input).
•
RXI: Receive text will flash when comm is active.
•
TX-I: Keeps intercom active during radio transmissions so in-aircraft conversations can continue
when a crew member is communicating out of the aircraft.
•
All Comms Artificial Sidetone feature so whomever is transmitting can still hear themselves and
other headsets will hear if they are selected/receiving the same transceiver.