Piper PA-28-161, Maintenance Manual

Page: 270 / 1104

PIPER AIRCRAFT, INC.
PA-28-161, WARRIOR III
MAINTENANCE MANUAL
PAGE 2
Nov 30/06
2D4
23-50-00
(c) Transceiver Operational Check
1 Perform a ramp test radio check by exercising the installed transceivers, microphone,
microphone key and audio over the headphones and speaker.
2 Verify that communications are loud and clear and push-to-talk (PTT) operation is
correct.
(d) Intercom System (ICS) Check
1 Set the intercom to the ALL mode (Crew and Pilot LED’s off).
2 Plug in headsets at each ICS position.
3 Adjust squelch and volume for each position and verify that the ICS is working
properly.
4 Check Pilot and Copilot ICS positions for isolation and proper operation of volume
and squelch controls.
5 Press the PA button. Verify that microphone audio is heard over the speaker.
(e) Aircraft Receivers Check
1 Select the audio source corresponding to each installed avionics unit and check for
audio over the headsets.
2 Check for Pilot/Copilot audio isolation when pressing the COM 1/2 button.
3 Press the SPKR button and verify that any selected audio is heard over the speaker.
(f) Music System Check
Connect a stereo music source to MUSIC 2. Press the CREW button to set the ICS to the
crew mode. Verify that stereo audio is heard in the passenger headsets only.
(2) In Flight
Verify proper operation of the marker lamps and marker audio, including the marker audio
mute function. Check proper operation of the marker sensitivity selection (using the SENS
button) by flying towards the outer marker position initially using HI sensitivity. When the OM
audio is just barely audible in the headset, switching to LO sensitivity should reduce or
eliminate the audio.
C. Adjustment (See Figure 2.)
CAUTION: USE ONLY A 2 MM (MAX BLADE WIDTH) FLAT-BLADE NONCONDUCTIVE SCREW
DRIVER AS AN ADJUSTMENT TOOL. BE CAREFUL WHEN INSERTING
ADJUSTMENT TOOL THROUGH THE TOP COVER. THE UNIT MAY BE DAMAGED
IF AN ADJUSTMENT TOOL IS ACCIDENTALLY FORCED AGAINST UNINTENDED
COMPONENTS OR CIRCUIT BOARD PATHS.
The following adjustments can be made through access holes in the top cover of the GMA 340:
(1) Marker beacon audio level.
Counter-clockwise adjustment increases the marker audio level.
(2) Marker beacon sensitivity.
Clockwise (CW) adjustment increases the sensitivity. LOW sensitivity can be adjusted without
affecting HIGH sensitivity setting. Adjusting HIGH sensitivity will, however, affect the LOW
sensitivity. If the HIGH sensitivity setting is adjusted, then the LOW sensitivity setting should be
checked and adjusted afterwards, as needed. If your GMA-340 top cover does not have the
marker beacon sensitivity adjustment access holes as indicated in Figure 2, and you need to
adjust the sensitivity, contact Garmin for instructions.
(3) Aircraft radio speaker output level.
(4) Pilot PA microphone speaker output level.
(5) Copilot PA microphone speaker output level.