
PS Engineering
PAC24 Series Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-240-0010
Page 3-4
Rev. 29, Sept. 2021
Split mode for Com 5, in normal (not TEL/Duplex) is possible.
Pilot on Com 2, with copilot on Com 3, Com 4 or Com 5, is also possible.
Note
: Split Mode does not turn off other (Nav, ADF, etc.) selected audio to
pilot
. Copilot does not hear
other selected radios.
3.6.2
Split Mode, Dual Panel
In a dual panel installation, both pilots have access to any combination of transceivers. Because there is
cross communication, each PAC24 knows the other unit’s transmitter selection. The audio panel designated
as “Pilot’s” will have transmission priority over the panel designated as copilot’s, when both panels are
keyed for transmit on the same radio.
It is not necessary to activate the split mode by holding the buttons in a dual installation.
3.6.3
Split Mode, Observer Panel (-04XX)
In observer mode, split mode is selected on the crew panel in the same manner as a single panel
(for example, press COM1 and COM2 for COM1/2 mode). The observer’s panel will split as in a
conventional dual panel installation.
3.7
Intercom Operation
3.7.1
IntelliVox® VOX-Squelch
No adjustment of the
IntelliVox
® squelch control is necessary. There is no field adjustment.
Through individual signal processors, the ambient noise appearing in all six microphones is con-
stantly being sampled. Non-voice signals are blocked. When someone speaks, only their micro-
phone circuit opens, placing their voice on the intercom.
The system is designed to block continuous tones, therefore people humming or whistling in
monotone may be blocked after a few moments.
For consistent performance, any headset microphone
must
be placed within ¼-
inch of your lips, preferably against them. (ref:
RTCA/DO-214, 1.3.1.1 (a
)).
It is also a good idea to keep the microphone out of a direct wind path. Moving
your head through a vent air stream may cause the
IntelliVox
® to open momen-
tarily. This is normal.
The
IntelliVox
® is designed to work with normal aircraft cabin noise levels (70 dB
and above). It loves airplane noise! Therefore, it may not recognize speech and
clip syllables in a quiet cabin, such as in the hangar, or without the engine run-
ning. This is normal.