PS Engineering PMA450 Installation Manual - Manual (Page 26)

PS Engineering
PMA450 Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0000 Page 3-6 Rev. 3, November 2014
MARKER, and turn the small knob to adjust the marker beacon volume. The green volume bar and numer-
ical readout will indicate the receiver volume in this menu. NOTE: marker Volume cannot be turned com-
pletely off.
NOTE: PMA450, P/N 050-450-0200, without Marker Beacon, will not have a Volume selection.
3.7.1 Marker Beacon Sensitivity
Press and hold the MKR button for about two seconds, or the letter H appears in the LCD display, indicat-
ing that the Marker beacon sensitivity in in the High Sense Mode. Repeat to switch back to Low Marker
Sense (“H” disappears.)
[Serial Number D1150 and below only: Marker Beacon sensitivity is set using an external toggle switch, if
desired. The PMA450 defaults to low sensitivity, and will be in high sensitivity if the switch is closed, con-
necting J2-Pin 30, to ground. ]
3.8 Intercom Operation (8)
3.8.1 IntelliVox® Intercom VOX-Squelch
No adjustment of the IntelliVox® squelch control is necessary. Through three 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 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)).
NOTE
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.
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 All 90015
Peltor 7003
7004 90010
90015
Pilot 11-20 & 11-90 90015
Sennheiser 90015
Telex Airman 750, Echelon
AIR3000 90015
90010
Table 3-1 Mic Muff ™ Part Numbers
3.8.2 Intercom Volume Control (1)
The smaller inner volume control knob adjusts the loudness of the intercom for the pilot and copilot. It has
no effect on selected radio levels, music input levels or passengers' volume level. The green volume bar
indicator shows the level of the crew volume by default.