Garmin GMA 350 Manual

GMA 350
pilot’s guide

Copyright © 2011 Garmin Ltd. or its subsidiaries. All rights reserved.
This manual reflects the operation of GMA 350 units with mod level 0 or later.
Some differences in operation may be observed when comparing the information
in this manual to earlier or later Mod status levels.
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September, 2011 190-01134-12 Rev. D Printed in the U.S.A.

LIMITED WARRANTY
This Garmin product is warranted to be free from defects in materials or
workmanship for two years from the date of purchase. Within this period, Garmin
will, at its sole option, repair or replace any components that fail in normal use.
Such repairs or replacement will be made at no charge to the customer for parts
and labor, provided that the customer shall be responsible for any transportation
cost. This warranty does not cover failures due to abuse, misuse, accident, or
unauthorized alterations or repairs. In addition, Garmin reserves the right to
refuse warranty claims against products or services that are obtained and/or used
in contravention of the law of any country.
THE WARRANTIES AND REMEDIES CONTAINED HEREIN ARE EXCLUSIVE AND IN
LIEUOFALLOTHERWARRANTIESEXPRESSORIMPLIEDORSTATUTORY,INCLUDING
ANY LIABILITY ARISING UNDER ANY WARRANTY OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE, STATUTORY OR OTHERWISE. THIS
WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS, WHICH MAY VARY FROM STATE
TO STATE.
IN NO EVENT SHALL GARMIN BE LIABLE FORANY INCIDENTAL,SPECIAL,INDIRECT
OR CONSEQUENTIAL DAMAGES, WHETHER RESULTING FROM THE USE, MISUSE,
OR INABILITY TO USE THIS PRODUCT OR FROM DEFECTS IN THE PRODUCT. Some
states do not allow the exclusion of incidental or consequential damages, so the
above limitations may not apply to you.
Garmin retains the exclusive right to repair or replace the unit or software, or to
offer a full refund of the purchase price, at its sole discretion. SUCH REMEDY SHALL
BE YOUR SOLE AND EXCLUSIVE REMEDY FOR ANY BREACH OF WARRANTY.
To obtain warranty service, contact your local GarminAuthorized Service Center. For
assistance in locating a Service Center near you, visit the GarminWeb site at“http://
www.garmin.com” or contact Garmin Customer Service at 800-800-1020.
CAUTION: Incorrect aircraft wiring could short the left channel or
both channels to ground if a monaural headset is plugged into
the stereo jacks. If wired incorrectly, fail-safe operation will not
work.

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GMA 350 Audio Panel
CONTROLS
GMA 350 Controls
21
14 15 1712 1311 19 20 1816
10
8642 3 5 7 9
1
NOTE: When a key is selected, a triangular annunciator above the key is
illuminated.
1
MKR/MUTE – Selects marker beacon receiver audio. Mutes the
currently received marker beacon receiver audio. Deactivates
automatically and marker beacon audio is heard when the next marker
beacon signal is received. Also, stops play of recorded COM audio.
2
COM1 – When selected, audio from the #1 COM receiver can be
heard. Press and hold to enable/disable monitored COM muting
during primary COM reception.
3
COM2 – When selected, audio from the #2 COM receiver can be
heard. Press and hold to enable/disable monitored COM muting
during primary COM reception.
4
NAV1 – When selected, audio from the #1 NAV receiver can be heard.
5
NAV2 – When selected, audio from the #2 NAV receiver can be heard.

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GMA 350 Audio Panel
6
– Selects and deselects audio from a telephone or entertainment
device connected to the Front Panel Jack. Audio from a telephone
connected to the rear of the audio panel is used if a device is not
connected to the Front Panel Jack. Press and hold to enable/disable
muting during reception.
7
MUS1 – Selects and deselects music entertainment audio. Press and
hold to enable/disable MUS1 muting during reception.
8
MUS2 – Selects and deselects music entertainment audio. Press and
hold to enable/disable MUS2 muting during reception.
9
MAN SQ – Manual Squelch annunciator. When lit, squelch is
controlled manually.
10
Volume Indicator – Indicates volume/squelch setting relative to full
scale.
11
Front Panel Jack – Used for an entertainment or telephone input.
12
MIC1 – Selects the #1 transmitter for transmitting. COM1 receive
is simultaneously selected when this key is pressed allowing received
audio from the #1 COM receiver to be heard. COM2 receive can be
added by pressing the COM2 Key. Selection of a second MIC button
initiates Split-COM mode. When in Split-COM mode, the pilot is
using COM1, the copilot is using the COM2.
13
MIC2 – Selects the #2 transmitter for transmitting. COM2 receive
is simultaneously selected when this key is pressed allowing received
audio from the #2 COM receiver to be heard. COM1 receive can be
added by pressing the COM1 Key. Selection of a second MIC button
initiates Split-COM mode. When in Split-COM mode, the pilot is
using COM1, the copilot is using the COM2.
14
PLAY – Press once to play the latest recorded memory block. Press
while audio is playing begins playing the previously recorded memory
block. Each subsequent press thereafter plays the previous block of
memory.

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GMA 350 Audio Panel
15
AUX – When selected, audio from the AUX inputs can be heard.
16
PILOT – Controls the pilot intercom system. Press and hold to toggle
3D Audio on/off for all headset positions.
17
COPLT – Controls the copilot intercom system. Press and hold to
toggle copilot configuration between crew and passenger.
18
PASS – Controls the passenger intercom system. Press and hold to
enable/disable passenger muting during reception.
19
SPKR – Selects and deselects the cabin speaker. COM, NAV, AUX, and
MKR receiver audio can be heard on the speaker. Press and hold for 2
seconds for Passenger Address (PA). The SPKR key flashes during PA.
20
Cursor (CRSR) Control Knob – Turn to move the cursor (flashing
white or blue annunciator) to the desired source.
21
Volume (VOL) Control Knob – Turn the smaller knob to control
volume or squelch of the selected source (indicated by the flashing
white or blue annunciator). When the volume control cursor is not
active press to switch to Blue-Select mode. If the volume control cursor
is active, press twice (once to cancel the cursor, twice to activate Blue-
Select mode).

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GMA 350 Audio Panel
FEATURES AND OPERATION
The GMA 350 Audio Panel provides the traditional audio selector functions
of microphone and receiver audio selection. The Audio Panel includes an
intercom system (ICS), a marker beacon receiver, and a COM clearance
recorder. Ambient noise from the aircraft radios is reduced by Avionics
Squelch (ASQ). When no audio is detected, ASQ processing further reduces
the amount of background noise. The MAN SQ Key toggles between manual
and automatic intercom system (ICS) squelch. In automatic ICS squelch
mode, threshold adjustments are handled automatically by the system. In
manual ICS squelch mode, individual threshold adjustments can be made
for the pilot, copilot, and passenger microphones by the crew. The ability to
adjust individual thresholds for each ICS position further reduces the amount
of background noise from the radios.
Pushbutton keys control audio selection. When a key is selected, a triangular
annunciator above the key is illuminated. Annunciator brightness is adjusted
automatically by photocell dimming. Key brightness is adjusted by the radio
dimming bus control. Three Aux inputs are available for additional avionics
or audio devices.
Upon installation, the unit may be configured in various ways depending
on aircraft type and the needs of the pilot.
POWER-UP
The GMA 350 performs a self-test during power-up. During the self-
test all Audio Panel annunciator lights illuminate for approximately two
seconds. Once the self-test is completed, most of the settings are restored
to those in use before the unit was last turned off.

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GMA 350 Audio Panel
MONO/STEREO HEADSETS
Stereo headsets are recommended when using the GMA 350. Using a
monaural headset in a stereo jack shorts the right headset channel output to
ground. While this does not damage the Audio Panel, a person listening on
a monaural headset hears only the left channel in both ears. If a monaural
headset is used at one of the passenger positions, any other passenger using
a stereo headset hears audio in the left ear only.
TRANSCEIVERS
NOTE: Transceiver functions may also be accessed via Voice Recognition
commands. Refer to theVoice Recognition section for more information.
Audio from the #1 or #2 COM receiver can be selected independently by
pressing the respective Key(s) (COM1 or COM2).
Pressing MIC1 or MIC2 selects the #1 or #2 transmitter and simultaneously
selects the related COM receiver (COM1 or COM2) allowing received
audio to be heard. The other COM receiver can be added by pressing the
respective key. During reception of audio from the COM radio selected for
transmission, audio from the other COM radio is muted.
ENABLING/DISABLING MONITORED COM MUTING
Press and hold COM1 or COM2 to enable/disable monitored COM
muting during reception of audio from the COM radio selected for
transmission. The aural message “Monitor Mute Enabled/Disabled”
is heard.

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GMA 350 Audio Panel
SPLIT-COM MODE
NOTE: Split COM performance is affected by the distance between
the COM antennas and the separation of the tuned frequencies. If the
selected COM frequencies are too close together, interference may be
heard during transmission on the other radio.
During Split-COM operation, both the pilot and the copilot can transmit
simultaneously over separate radios.
Pressing both MIC Keys simultaneously initiates Split-COM Mode
(i.e., COM1/COM2). The respective COM1/MIC1 or COM2/MIC2
annunciators are illuminated indicating Split-COM operation. Split-COM
operation is cancelled by pressing one of the selected MIC Keys again.
In Split-COM mode, the pilot is uses COM1 and the copilot is uses
COM2.
COM2 Radio is Selected
Selecting a COM Radio for Transmit

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GMA 350 Audio Panel
TRANSMIT INDICATIONS
During COM transmission, the active transceiver (MIC1 or MIC2) Key
Annunciator flashes approximately once per second.
During Split-COM transmission, the MIC1 annunciator flashes when
the pilot’s microphone PTT is pressed. The MIC2 annunciator flashes
when the copilot’s microphone PTT is pressed.
COM Radio Transmit Indication
Annunciator
Flashes During
Transmission
RECEIVERS
NOTE: Receiver functions may also be accessed via Voice Recognition
commands. Refer to theVoice Recognition section for more information.
Pressing the NAV1 and/or NAV2 Key(s) selects/deselects the receiver
audio for the corresponding navigation radio source. The selected audio
source can be heard over the headset and the speaker (if selected). All
radios can be selected individually or simultaneously.
Selecting a NAV Radio Receiver

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GMA 350 Audio Panel
MARKER BEACON RECEIVER
The marker beacon receiver detects any marker beacon signal within
the reception range of the aircraft.
When a marker beacon signal is detected, the lamps illuminate, and
an associated keyed-tone is heard when MKR audio is selected. Marker
beacon lamps operate independently of any audio selection and cannot
be turned off.
Marker Beacon Key & Lamps
The marker beacon signal sensitivity threshold can be set to High, Low,
or User Selectable (toggle switch required).
The receiver detects the three marker tones (outer, middle, and inner).
Audio
Frequency Audio Keying Lamp Actuated
400 Hz
(Outer) − − − − − Blue
1300 Hz
(Middle) −−−−−Amber
3000 Hz
(Inner)  White
The GMA 350 provides three states of marker beacon operation; On,
Muted, and Deselected. The MKR/MUTE key annunciator indicates
when marker beacon audio is selected. Marker beacon audio is not
heard when the annunciator is off or when the annunciator is on with the
marker beacon audio muted.

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GMA 350 Audio Panel
Turning Marker Beacon Audio On
With the MKR/MUTE annunciator off, press the MKR/MUTE Key
to activate marker beacon audio and illuminate the MKR/MUTE
annunciator.
Muting Marker Beacon Audio
During marker beacon audio reception, press the MKR/MUTE Key
to mute the audio. The MKR/MUTE annunciator remains lit, but the
current marker tone is silenced. Audio muting deactivates automatically
and marker beacon audio is heard when the next marker beacon signal
is received.
Deselecting Marker Beacon Audio
To deselect marker beacon audio, press the MKR/MUTE Key twice
during marker beacon reception or once if a marker beacon signal is
not detected.

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GMA 350 Audio Panel
INTERCOM SYSTEM (ICS)
NOTE: Intercom functions may also be accessed via Voice Recognition
commands. Refer to theVoice Recognition section for more information.
The GMA 350 includes a six-position intercom system (ICS), two MUSIC
inputs, and one telephone/entertainment input for the pilot, copilot and
passengers. The intercom provides Pilot, Copilot, and Passenger audio
isolation.
Intercom Controls
Press the PILOT, COPLT, and/or PASS Keys to distribute as required.
If the annunciators are lit, those positions will share intercom audio. If an
annunciator is NOT lit that position is isolated from the others.
COPILOT CONFIGURED AS CREW OR PASSENGER
NOTE: When the copilot position is configured as a passenger, the COPLT
Key is disabled and the copilot headset is treated as a ‘passenger’ for
intercom and entertainment audio distribution.
The copilot position can be configured as crew (COPLT Key enabled)
or as a passenger (COPLT Key disabled). Pressing and holding the
COPLT Key toggles the copilot position configuration between passenger
and crew. The aural message “Copilot Configured as Passenger” or
“Copilot Configured as Crew” is heard.

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GMA 350 Audio Panel
INTERCOM MODES
NOTE: In the following modes the copilot position is configured as crew.
NOTE: In the default ICS configuration, only the pilot and copilot
positions can hear aircraft alerts.
All Intercom Mode
In ‘All Intercom’ mode the Pilot, Copilot, and Passengers hear each
other and hear the aircraft audio.
ICS Keys Mode Operation
Aircraft Audio
PASS
PILOT COPLT
Pilot Isolate Mode
In ‘Pilot Isolate’ mode the Pilot, Copilot, and Passengers hear the
aircraft audio. The Copilot and Passengers also hear each other.

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GMA 350 Audio Panel
ICS Keys Mode Operation
Aircraft Audio
PASS
PILOT COPLT
Passenger/Crew Isolate Mode
In ‘Passenger/Crew Isolate’ mode the Pilot and Copilot hear the
aircraft audio and each other. The Passengers hear each other.
ICS Keys Mode Operation
Aircraft Audio
COPLTPILOT PASS

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GMA 350 Audio Panel
Copilot Isolate Mode
In ‘Copilot Isolate’ mode the Pilot and Passengers hear the aircraft
audio and each other. The Copilot has the option to use Split-COM
mode.
ICS Keys Mode Operation
Aircraft Audio
PASS
PILOT
COPLT
Split-COM Mode
(Optional)
All Isolate Mode
In ‘All Isolate’ mode the Pilot hears the aircraft audio. The Copilot
has the option to use Split-COM mode. The Passengers hear each other.
ICS Keys Mode Operation
Aircraft Audio
COPLTPILOT PASS
Split-COM
(Optional)

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GMA 350 Audio Panel
Pilot & Copilot Isolate Mode
In ‘Pilot & Copilot Isolate’ mode the Pilot and Passengers hear the
aircraft audio. The Copilot has the option to use Split-COM mode.
ICS Keys Mode Operation
Aircraft Audio
PASS
PILOT COPLT
Split-COM
(Optional)
Pilot & Passenger Isolate Mode
In ‘Pilot & Passenger Isolate’ mode the Pilot and Copilot hear the
aircraft audio. The Passengers hear each other.
ICS Keys Mode Operation
Aircraft Audio
COPLT
PILOT PASS

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GMA 350 Audio Panel
Copilot & Passenger Isolate Mode
In ‘Copilot & Passenger Isolate’ mode the Pilot can hear the aircraft
audio. The Copilot has the option to use Split-COM mode. The
Passengers hear each other.
ICS Keys Mode Operation
Aircraft Audio
COPLT
PILOT PASS
Split-COM
(Optional)
INTERCOM VOLUME AND SQUELCH
The VOL/CRSR Knob controls selection and volume or manual squelch
adjustment for audio sources that may not be adjustable anywhere else in
the system. The small knob controls the volume or squelch. Turning the
large knob activates and/or moves the cursor (flashing white annunciator/
or flashing blue annunciator in Blue-Select Mode) to select the audio
source to adjust. The cursor will time-out after a few seconds and the
position of the cursor will always default back to the PILOT Key. Pressing
the small knob cancels the cursor.
Blue-Select Mode (Telephone/Entertainment
Distribution)
The music (MUS1/MUS2) and telephone/entertainment ( ) audio
are distributed using the Blue-Select Mode. The following example
indicates that the pilot, copilot, and passengers will all hear the
telephone/entertainment audio.

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GMA 350 Audio Panel
Blue-Select Mode (Telephone/Entertainment Distribution)
The Blue-Select Mode is entered by pressing the small knob when the
volume control cursor (flashing white annunciator) is not active. If the
volume control cursor is active, press the small knob twice. The first
press will cancel the volume control cursor, the second will activate
Blue-Select Mode.
The annunciator over the Key will be flashing blue. Any
combination of the annunciators over the PILOT, COPLT, and
PASS buttons may be blue. Select the desired button to turn the blue
annunciator on or off to distribute the telephone/entertainment audio to
selected crew/passenger positions. Turn the large knob to select MUS1
or MUS2 and select the crew positions to receive the music audio.
Selecting any key other than PILOT, COPLT, PASS, MUS1, MUS2,
or will cancel Blue-Select Mode. Pressing the small knob will
also cancel Blue-Select Mode. After approximately ten seconds with no
input, the Blue-Select Mode will automatically cancel.
Adjusting Intercom Volume
When the cursor is on PILOT, COPLT, or PASS, the Volume Control
Knob adjusts the intercom volume for the listener.
Adjusting Manual Squelch
When the cursor is on MAN SQ, the Volume Control Knob adjusts
the ICS Squelch Threshold (the volume level that must be exceeded to
be heard over the intercom).

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GMA 350 Audio Panel
Adjusting Speaker Volume
When the cursor is on SPKR, the Volume Control Knob adjusts the
speaker volume of the selected sources (COM, NAV, AUX, MKR).
Adjusting MKR, AUX,
,
and MUSIC Volume
When the cursor is on MKR, AUX, , MUS1 or MUS2, the Volume
Control Knob adjusts the individual volume of the selected source.
Volume/Squelch Control
Manual Squelch Annunciator;
Off for Automatic Squelch, On
for Manual Squelch Relative Volume/ Squelch Scale
Volume or Manual Squelch Cursor
SPEAKER
All of the radios can be heard over the cabin speaker. Pressing the SPKR
Key selects and deselects the cabin speaker. Speaker audio is muted when
the PTT is pressed. Certain aural alerts and warnings (autopilot, traffic,
altitude) are always heard on the speaker, even when the speaker is not
selected.
Speaker Key