PS Engineering PMA7000H Installation Manual - Manual (Page 22)

PS Engineering
PMA7000H Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-780-0429 Page 3-3 Rev. 4, Dec 2012
Note:
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 Split Mode ICS
In split mode, the pilot and copilot are usually isolated from each other on the intercom, simultaneously
using their respective radios. Depressing the ICS button in Split Mode will activate VOX intercom between
the pilot and copilot positions. This permits intercommunication when desired between the crew. Pressing
the ICS 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 (80 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.