PS Engineering PMA8000 Installation Manual - Manual (Page 21)

PS Engineering
PMA8000 Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-890-0000 Page 3-3 Revsion 10, September 2005
3.4.1.1 Public Address Function
To access PA function, press the Mute (6) and SPR (5) buttons simultaneously. The COM1 and COM2
receive LEDs will blink to indicate the audio panel is in PA mode. The copilot can continue to use the se-
lected com radio while the pilot will be heard over the speaker. To exit, press Mode and SPR again.
We recommend that some switching means be used to transfer the audio from the cockpit speaker to a
cabin speaker for public address. This will prevent feedback. See section 2.4.11
3.5 Split Mode
The split mode can be activated at any time by pressing the Com 1 and Com 2 XMT buttons at the same
time. This places the pilot on Com 1 and the Copilot on Com 2.
Pilot on Com 2 and Copilot on Com 1 is not possible.
N o t e :
Due to the nature of VHF communications signals, and the size constraints in
general aviation aircraft, it is probable that there will be some bleed-over in the
Split mode, particularly on adjacent frequencies.
PS Engineering makes no warranty about the suitability of Split Mode in all air-
craft conditions.
Note: Split Mode does not turn off other (Nav, ADF, etc.) selected audio to pilot. However, the copilot will only hear
the selected communications receiver.
3.5.1 Mute Button, Split Mode ICS (6)
In split mode, the pilot and copilot are usually isolated from each other on the intercom, simultaneously
using their respective radios. Depressing the “Mute” button (6) in Split Mode will activate VOX intercom
between the pilot and copilot positions. This permits intercommunication when desired between the crew.
Pressing the Mute button again disables this crew intercom function.
3.6 Intercom Operation
3.6.1 IntelliVox® VOX-Squelch
No adjustment of the IntelliVox® squelch control is necessary. There is no field adjustment. Through three
individual signal processors, the ambient noise appearing in all six microphones is constantly being sam-
pled. 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 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 momentarily. 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 running. This is normal.
For optimum microphone performance, PS Engineering recommends installation of a Microphone Muff
Kit from Oregon Aero (1-800-888-6910). This will not only optimize VOX performance, but will improve
the overall clarity of all your communications.