Operating instructions

202-890-0602 Page 9
July 2008 PMA8000MP3 Pilot Guide
ing 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 indi-
cator 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 accurate location of the Outer Marker. Holding the MKR button
for one second activates marker test lamp, labeled "T/M" and illumi-
nates all three lamps simultaneously to assure the lamps (internal and
external) are in working order. TST does not activate MM autopilot
sense output. Releasing the button returns to the last sensitivity.
Pressing the marker mode select (“T/M”) for one second will also
cause the marker audio to mute for that beacon. The next beacon re-
ceived will re-activate the audio.
Internal Recorder System
The Intercom Recording System is a digital recording system allow-
ing automatic storage and playback of aircraft radio traffic.
Operating as a continuous loop recorder, (first message received will
be the last heard), the recorder has 30 seconds of recording time, or
up to 16 messages. With its own built in VOX circuit, there are no
buttons to press to start recording. The system automatically begins to
record the instant the radio becomes active. Only the com radio se-
lected for transmit is recorded, and only the pilot and copilot will hear
the playback audio.
Operation
Recording is automatic. To play back the last recorded message, press
and hold the COM Receive pushbutton associated with the selected
radio transmitter for about one
(1) second. You must wait for
the message to finish playing
before accessing the prior mes-
sage. To cancel the playback,
press and hold the playback but-
ton for two seconds (2). The next
time the button is pressed for one
(1) second, the next earlier mes-
sage will be heard.