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6
PMA7000MS-Option CD Pilot Guide
1.6
Intercom Operation
1.6.1
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 constantly being sampled. Non-voice
signals are blocked. When someone speaks, only their microphone circuit
opens, placing their voice on the intercom.
The system is designed to block continuous tones, therefore people hum-
ming 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 momentarily. This is normal.
The
IntelliVox
® is designed to work with normal aircraft cabin
noise levels (70 dB and above). It loves airplane noise! There-
fore, it may not recognize speech and clip syllables in a quiet
cabin, such as in the hangar, or without the engine running.
This is normal.
For optimum microphone performance, PS Engineering recommends instal-
lation of a Microphone Muff Kit from Oregon Aero (1-800-888-6910). This
will not only optimize VOX performance, but will improve the overall clar-
ity of
all
your communications.
1.6.2
Intercom Volume Control
The intercom volume control is the smaller concentric knob on the left side
of the unit. This volume control knob adjusts the loudness of the intercom
for the pilot and copilot only. It has no effect on selected radio levels, music
input levels or passengers' volume level.
Adjust the radios and intercom volume for a comfortable listening level for
the pilot. Most general aviation headsets today have built-in volume con-
trols; therefore, passenger volume can be adjusted at the headset. If desired,
passenger volume level can be reduced by a screwdriver adjustment at the
top of the tray.
1.6.2.1
Mono headsets in Stereo Installation
All passenger headsets are connected in parallel. Therefore, if a monaural
headset is plugged in to a PMA7000MS-CD Stereo installation, one chan-
nel will be shorted. Although no damage to the unit will occur, all passen-
gers will lose one channel, unless they switch to the “MONO” mode on the
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7
PMA7000MS Option CD Pilot Guide
headset. PS Engineering modifies headsets to add stereo capability, using
high-fidelity speakers. Contact factory (865-988-9800 or www.ps-
engineering.com) for details.
1.6.3
Intercom Modes
The lower switch on the left side is a 3-position mode switch that allows the
pilot to tailor the intercom function to best meet the current cockpit situa-
tion. The description of the intercom mode function is valid
only when the unit is not in the "Split" mode. Then, the pi-
lot and copilot intercom is controlled with the ICS button.
I
SO
:
(Up Position): The pilot is isolated from the intercom
and is connected only to the aircraft radio system. He will
hear the aircraft radio reception (and sidetone during radio
transmissions). Copilot will hear passengers’ intercom and
Entertainment 1, while passengers will hear copilot inter-
com and Entertainment 2. Neither will hear aircraft radio
receptions or pilot transmissions.
Mode
Pilot
Hears
Copilot
Hears
Passen-
gers Hear
Telephone
Comments
ISO
A/C Radios
Pilot Side-
tone
(during
radio trans-
mission)
Passen-
gers
Copilot
Music Input
1 (CD)
Copilot
Passen-
gers
Music 2
“Phone Booth”
mode
Pilot has exclu-
sive use of the
telephone
This mode allows the pilot to
communicate without the others
bothered by the conversations.
Copilot and passengers can con-
tinue to communicate and listen
to music
ALL
Radios
Copilot
Passen-
gers
CD Music
Radios
Pilot
Passen-
gers
CD Music
Radios
Pilot
Copilot
Passen-
gers
Music 2
All have ac-
cess to phone
through Hook
Switch. Pilot
access through
TEL switch.
All hear tele-
phone audio if
off hook.
This mode allows all on
board to hear radio reception
as well as communicate on
the intercom. Music and in-
tercom is muted during inter-
com and radio communica-
tions
CREW
Radios
Copilot
CD Music
Radios
Pilot
CD Music
Passen-
gers
Music 2
Pilot and
copilot don’t
have phone
access un-
less mic sel
in TEL. Pas-
sengers
have phone
through
Hook Switch
Passengers
hear phone
This mode allows the pilot
and copilot to concentrate on
flying while the passengers
can communicate amongst
themselves
