PS Engineering PM1200 Installation Manual - Manual (Page 5)

200-196-0104 Page 5 March 2013 Rev. 12
green to red when a radio PTT is pressed.
7. Verify proper intercom operation for pilot and copilot.
For more information, consult Section 3.
8. Verify proper transmit and receive operation on the
copilot position, noting that the copilot PTT switch
allows proper transmission on the selected transceiver.
9. Verify proper Intercom system operation in the ALL and
ISO modes.
10. Verify that the intercom system does not adversely affect
any other aircraft system by systematically switching the
unit on and off, while monitoring the other avionics and
electrical equipment on the aircraft.
11. PTT ICS– Push the copilot volume control to activate the
PTT-ICS mode. Verify that the mic audio is heard when the
intercom push to talk switch is activated.
Section 3 OPERATION
3.1 On/Off and Volume
Press the left hand knob to turn the unit on and off.
This is also the fail-safe position. Whenever the unit is
off, or power removed, the pilot’s headset is connected
directly to the aircraft audio system.
The pilot's volume control knob adjusts the loud-
ness of the intercom and music for the pilot's headset
only. It has no effect on aircraft radio volume level,
allowing an additional degree of aircraft radio listen-
ing flexibility. The copilot's volume control adjusts the
intercom volume for the copilot.
3.2 Squelch
The PM1200 incorporates PS Engineering’s revo-
lutionary Advanced Microphone Processing (AMP)
and IntelliVox™ intercom squelch. No adjustment of
the squelch control is required. Through individual
signal processors, the ambient noise appearing in both
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. The IntelliVox®
is designed to work with normal aircraft cabin noise
levels (70 dB and above). Therefore, it may not recog-
nize speech and clip syllables in a quiet cabin, such as
in the hangar, or without the engine running. This is
normal. For best performance, the headset microphone
must be placed within ¼ inch of your lips, preferably
against them. It is also a good idea to keep the micro-
phone out of a direct wind path. Moving your head
through a vent air stream may cause the IntelliVox™
to open momentarily. This is normal.
For optimum microphone performance, PS Engineering, Inc.
recommends installation of a Microphone Muff Kit (provided).
This will not only optimize VOX performance, but will improve
the clarity of all your communications
In some extremely high noise environments, it
may be desirable to have a push to talk (PTT) inter-
com, instead of relying on voice-activation (VOX). In
the PM1200 audio panel the PTT intercom capability
is added. To operate the PTT, push the PTT-ICS con-
trol switch on the copilot volume control. Using an
external ICS PTT switch for pilot and copilot will al-
low voice on the intercom.
3.3 Mode Select
The center switch is a mode control that allows the
pilot to tailor the intercom function to suit flight condi-
tions. Regardless of configuration, the pilot will al-
ways hear the aircraft radio. NOTE: If there is a
power failure to the PM1200, or if the power switch is
turned off, the copilot will not hear the aircraft radio.
Only the pilot is connected directly to the aircraft ra-
dio.
ISO (Up Position): The pilot is isolated from the
intercom and is connected only to the aircraft radios.
He will hear the aircraft radio reception (and sidetone
during radio transmissions). Copilot and passengers
will hear themselves and music but not the aircraft
radio traffic.
ALL (Middle position): All parties will hear the
aircraft radio, intercom, and music. However, during
any ICS or radio communications, the music volume
automatically mutes. The music volume increases
gradually back to the original level after communica-
tions have been completed.
CREW (with expansion and 11960-EXP ONLY,
down position, unlabeled): Pilot and copilot have ac-
cess to aircraft radios, and hear Music input to
PM1200. Passengers do not hear aircraft radio or pilot
and copilot, but can talk to each other, and hear Music
2. In non-expanded systems, the down and middle po-
sitions operate the same way.
The music input on the expansion unit will only be
active in Crew mode, otherwise, music from the
PM1200 EXP will be heard by passengers.