PS Engineering
PAC24 Series Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-240-0010
Page 3-5
Rev. 29, Sept. 2021
For optimum microphone performance, PS Engineering recommends installation of a Micro-
phone Muff Kit from Oregon Aero (1-800-888-6910). This will not only optimize VOX perfor-
mance, but will improve the overall clarity of
all
your communications.
Table 3-1 Mic Muff ™ Part Numbers
Manufacturer
Model
Mic Muff™ Part Number
Bose
Dynamic
Electret
M87 Dynamic
90010
90015
90020
David Clark
H10-30
H10-20, H10-40
H10-13.4
90010
90015
90015
Lightspeed
15K & 20K
90015
Peltor
7003
7004
90010
90015
Pilot
11-20 & 11-90
90015
Sennheiser
90015
Telex
Airman 750
AIR3000
90015
90010
3.7.2
Volume Control (3)
The volume control is a concentric knob. The inner knob adjusts the loudness of the intercom for the pilot
(in single panel installation) and the outer knob controls copilot and passenger volume. It has no effect on
selected radio levels or music input levels.
In dual installation, the inner knob controls the main volume (the person connected to the audio panel) and
the outer knob controls the passengers.
When a panel mounted IntelliPax (11606) expansion unit is used, only the expansion volume controls are
active. The knob on the 11606, or the trimmer pots on the 11606R control passenger intercom volume.
3.7.3
Intercom Modes (5)
The lower switch on the left side of the audio panel is a 3-position mode switch that allows the crew to tai-
lor the intercom function to best meet the current cockpit situation.
3.7.3.1
Single Installation Intercom Modes
I
SO
:
(Up Position): The pilot connected to the PAC24 is isolated from the intercom and is connected only
to the aircraft radio system. He will hear the selected aircraft radio reception (and sidetone during radio
transmissions). The copilot will hear passengers’ intercom and entertainment, while passengers will hear
copilot, intercom and entertainment.
A
LL
:
(Middle Position): All parties will hear the aircraft radio and intercom. All will hear entertainment.
During any radio or intercom communications, the music volume automatically decreases. The music vol-
ume increases gradually back to the original level after communications have been completed.
C
REW
(Down Position): Pilot copilot and passengers are connected on one intercom channel and have ac-
cess to the selected aircraft radios. They may also listen to Entertainment. Because the single panel, non-
expansion PAC24 (and KMA 24H) uses the same output for the copilot and passenger, “Crew” mode is not
possible (Unless expansion module, p/n 11606 is used)
3.7.3.2
Dual Installation Intercom Modes
I
SO
:
(Up Position): The primary pilot connected to the PAC24 is isolated from the intercom and is connect-
ed only to the aircraft radio system. He will hear the selected aircraft radio reception (and sidetone during
radio transmissions). The crewmember on the other audio panel will hear locally selected radio audio, pas-
sengers’ intercom and entertainment, while passengers will hear the radio, intercom and entertainment.