PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600
Page 3-4
Rev. 5, August 2020
NOTE: Switched Inputs can be renamed at the configuration set up. See §
In SPLIT mode, only the pilot will hear selected navigation audio.
Speaker Amplifier (7)
To activate the PMA450B cockpit speaker output, press and hold the bottom line-select button (SPR) for one
second or until SPR appears in the display.
In “Split Mode” all audio that the pilot hears will also be present in the speaker.
Unswitched audio #1 & #2, (the inputs dedicated to autopilot disconnect, altimeter warning, etc.) will come
through the speaker regardless of the speaker button position.
When a cell phone call is active, the selected radio audio is removed from the speaker.
Depending on installation, important audio annunciations such as radar altimeter or autopilot disconnect will
come over the speaker even if it is not selected, while other unswitched, but muted inputs, such as GPS alerts,
will only be present if the SPR button is selected. Consult your professional avionics installer for these im-
portant configuration details.
Unswitched
Input
Hear in
Fail Safe
(Pilot)
Hear in
Crew Headset
Hear in SPR
1
Yes
Yes
Yes
2
No
Yes
Yes
3
No
Yes
When SPR selected
4
No
Yes
When SPR selected
3.6.1
Public Address Function
To access PA function, press and hold the N1 button for more than 1 second, until the display changes to
PA
SPR
.
When PA mode is active, all microphones except for the Pilot will be disabled for complete and uninterrupted
announcements.
The pilot microphone will be heard on the speaker and headsets when the pilot PTT is used.
The copilot can continue to use the selected com radio while the pilot will be heard over the speaker.
