PS Engineering
PMA8000BT Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-890-0702
Page 3-3
Rev. 1, Oct. 2010
mic will be transferred to the selected Com radio. The telephone party will not hear ATC communic a-
tions, and vice versa.
In
CREW
mode, only the pilot and copilot are connected to the telephone. Passengers will not hear the
telephone. The pilot and copilot will also have transmit capability on the other selected transceiver.
In
ISO
intercom mode, when the PMA8000BT is in the
TEL
mode, the pilot position is in the "Phone
Booth." Only the pilot will hear the telephone, and only he will be heard. He will also have access to Com
1 or 2, and will transmit on that radio using the PTT. All selected audio is provided to the pilot.
NOTE
Because the cell-phone uses an intercom circuit, all stations on that circuit will lose intercom capability
when the cell phone is in use.
3.4.1
Cell phone Sidetone
As shipped from PS Engineering, the PMA8000BT does NOT provide cellular telephone sidetone (the
user’s voice fed back to the headset). Some cell phones do not provide sidetone. In PMA8000BT audio
panels, Telephone sidetone can be enabled by pressing the TEL and ADF buttons for more than one sec-
ond.
3.5 Speaker Amplifier (5)
The
SPR
in the lower right section stands for speaker. This switch will place all selected audio on the
cockpit speaker when this switch is selected. Except for the unswitched audio, the speaker amplifier is not
active in the "Split Mode”.
Unswitched audio, (the inputs dedicated to autopilot disconnect, altimeter warning, etc.) wi ll come
through the speaker regardless of the speaker button position.
Depending on installation, important audio annunciations such as radar altimeter or autopilot disconnect
will come over the speaker even if it is not selected, while other unswitched, but muted inputs, such as
GPS alerts, will only be present if the SPR button is selected. Consult your professional avionics installer
for these important configuration details.
3.5.1.1
Public Address Function
To access PA function, press the
Mute
and
SPR
buttons simultaneously. The pilot
microphone will be heard on the speaker when the pilot PTT is used. The copilot
can continue to use the selected com radio while the pilot will now be heard
over the speaker. During Public Address, the
Mute
and
SPR
buttons will
flash. To exit PA mode, push
Mute
and
SPR
again.
3.6 Marker Beacon Operation (10)
The Marker Beacon Receiver uses visual and audio indicators to alert you when the aircraft passes over a
75 MHz transmitter.
The Blue lamp, labeled “O”, is the Outer Marker lamp an d has an associated 400-Hertz 'dash' tone. The
lamp and tone will be keyed at a rate of two tones/flashes per second when the aircraft is in the range of
the Outer Marker Beacon.
The Amber lamp, labeled “M”, is the Middle Marker lamp and is coupled with a 1300 Hertz tone. It is
keyed alternately with short 'dot' and long 'dash' bursts at 95 combinations per minute.
The White lamp, labeled “I”, is the Inner marker and has a 3000 Hertz 'dot' tone. The lamp and tone will
be keyed at a rate of six times per second.
The audio from the Marker Beacon Receiver can be heard by selecting the "
MKR
" push-button switch. To
adjust the volume level, there is a service adjustment located on the top of the unit.
A pushbutton is used to set the receiver sensitivity and to test the indicator lamps mute the marker audio.
Use "
HI
" sensitivity initially. This allows you to hear the outer marker beacon about a mile out. Then
touch the smaller MKR button to switch into Low Sensitivity mode. “
LO
” sensitivity gives you a more
