Garmin GMA 350 User 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.

Garmin International, Inc., 1200 East 151st Street, Olathe, Kansas 66062, U.S.A.
Tel: [phone] Fax: [phone]

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Tel: [phone] Fax: [phone]

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Tel: [phone] Fax: [phone]

Web Site Address: www.garmin.com

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trademarks may not be used without the express permission of Garmin.

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
LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED OR STATUTORY, 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 FOR ANY 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 Garmin Authorized Service Center. For
assistance in locating a Service Center near you, visit the Garmin Web 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.

GMA 350 Audio Panel

CONTROLS

1

NOTE:

8642 3 5 7 9

14 15 1712 1311 19

GMA 350 Controls

1816

When a key is selected, a triangular annunciator above the key is

10

20

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.

21

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

4

NAV1

5

NAV2

– When selected, audio from the #1 NAV receiver can be heard.

– 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

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

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

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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– Selects the #1 transmitter for transmitting. COM1 receive

– Selects the #2 transmitter for transmitting. COM2 receive

– Press once to play the latest recorded memory block. Press

Garmin GMA 350 Pilot’s Guide

5

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 Blue­Select 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 self­test 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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7

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 the Voice 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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SPLIT-COM MODE

GMA 350 Audio Panel

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

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Selecting a COM Radio for Transmit

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9

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.

Annunciator

Flashes During

Transmission

COM Radio Transmit Indication

RECEIVERS

NOTE:

Receiver functions may also be accessed via Voice Recognition

commands. Refer to the Voice 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

400 Hz
(Outer)

1300 Hz
(Middle)

3000 Hz

(Inner)

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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− − − − −

−−−−−


Garmin GMA 350 Pilot’s Guide

Audio Keying Lamp Actuated

Blue

Amber

White

11

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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INTERCOM SYSTEM (ICS)

GMA 350 Audio Panel

NOTE:

Intercom functions may also be accessed via Voice Recognition

commands. Refer to the Voice 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:

NOTE:

In the following modes the copilot position is configured as crew.

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.

Aircraft Audio

PILOT COPLT

PASS

ICS Keys Mode Operation

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

Aircraft Audio

PILOT

COPLT

PASS

ICS Keys Mode Operation

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.

Aircraft Audio

COPLTPILOT

ICS Keys Mode Operation

PASS

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Garmin GMA 350 Pilot’s Guide

15

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.

Split-COM Mode

(Optional)

Aircraft Audio

COPLT

PILOT

PASS

ICS Keys Mode Operation

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.

Split-COM

16

Aircraft Audio

ICS Keys Mode Operation

Garmin GMA 350 Pilot’s Guide

(Optional)

COPLTPILOT

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PASS

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.

Split-COM

Aircraft Audio

(Optional)

PILOT COPLT

ICS Keys Mode Operation

PASS

Pilot & Passenger Isolate Mode

In ‘Pilot & Passenger Isolate’ mode the Pilot and Copilot hear the

aircraft audio. The Passengers hear each other.

Aircraft Audio

PILOT PASS

ICS Keys Mode Operation

COPLT

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Garmin GMA 350 Pilot’s Guide

17

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.

Split-COM

Aircraft Audio

(Optional)

PILOT

ICS Keys Mode Operation

COPLT

PASS

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.

Manual Squelch Annunciator;

Off for Automatic Squelch, On

for Manual Squelch

Volume or Manual Squelch Cursor

Volume/Squelch Control

Relative Volume/

Squelch Scale

SPEAKER

All of the radios can be heard over the cabin speaker. Pressing the
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.

SPKR

20

Speaker Key

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GMA 350 Audio Panel

Passenger Address Mode (PA Mode)

Press and hold the

SPKR

Key for 2 seconds to initiate Passenger
Address Mode. PA Mode is annunciated by a rapid blinking of the
SPKR annunciator. When in PA Mode the crew can use the PTT “Push­to-Talk” button to deliver announcements over the speaker, to the
passenger headsets, or both depending on configuration.

Split-PA Mode

During Split-PA Mode the pilot can continue to use the radio(s) while
the copilot delivers PA announcements. To initiate Split-PA Mode, first
enter Split-COM Mode by pressing both MIC Keys simultaneously,
then press and hold the SPKR Key for 2 seconds.

3D AUDIO

3D Audio is useful when multiple audio sources are present. By using
different responses in each ear, 3D audio processing creates the illusion that
each audio source is coming from a unique location or seat position.

Because this feature uses different signals for left and right channels, it
requires wiring for stereo intercom and stereo headsets. If 3D audio is
activated when mono headsets are in use, the listener will still hear all audio
sources; however, there is no benefit from location separation.

With a single COM selected and 3D Audio enabled, the listener hears
the audio source at the 12 o’clock position. If both COMs are selected,
the listener hears COM1 at 11 o’clock and COM2 at the 1 o’clock position.
All other intercom positions are processed to sound like their relative
seat location. By default, the GMA 350 assumes the pilot sits in the left
seat. A Garmin authorized service center can make changes to the default
configuration.

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GMA 350 Audio Panel

Enabling 3D Audio

Press and hold the

PILOT

Key to toggle 3D audio processing on and
off for all headset positions. When 3D Audio is enabled, the aural
message “3D audio left” is heard in the left ear followed by “3D audio
right” in the right ear. If the aural messages are not heard in only the
left and then the right ear respectively, the cause may be aircraft wiring
or headset settings. Refer to the following table if a headset or aircraft
wiring problem is suspected.

3D Audio Troubleshooting

Symptom(s) Cause(s) Solution(s)

“3D audio
left” message
heard in both
ears.

“3D audio
right” message
not heard

“3D audio
left” message
heard in both
ears, followed
by “3D audio
right” message
heard in both
ears

Mono headset in use 1) Use a stereo headset

1)

Stereo headset in use

2)

with mono/stereo
switch set to ‘mono’

Aircraft wiring has

3)

left audio wired to
both left and right
channels of stereo
headset jack

Mono headset in use 1) Use a stereo headset

1)

Stereo headset in use

2)

with mono/stereo
switch set to mono

Incorrect aircraft

3)

wiring (left/right
shorted together)

2) Set mono/stereo switch on
headset to ‘stereo’

3) If after checking solutions #1
and #2 see a service center as
soon as possible to inspect/
correct wiring. This wiring fault
can cause fail-safe audio not to
function.

2) Set mono/stereo switch on
headset to ‘stereo’

3) If after checking solutions #1
and #2 see a service center as
soon as possible to inspect/
correct wiring. This wiring fault
can cause fail-safe audio not to
function.

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GMA 350 Audio Panel

3D Audio Troubleshooting

Symptom(s) Cause(s) Solution(s)

“3D audio
right” message
heard in both
ears. “3D
audio left” not

Incorrect aircraft

1)

wiring (right channel
used for mono
instead of left or left/
right swapped)

1) See a service center as soon
as possible to inspect/correct
wiring. This wiring fault can
cause fail-safe audio not to
function.

heard
“3D audio

left” message
heard in
right ear only
followed by
“3D audio
right” message
heard in left
ear only

1) Stereo headset is on
backwards

2) Incorrect aircraft
wiring (left/right
channels swapped)

1) Verify correct orientation from
the left/right indication on
each side of the headset or
the position of the boom MIC
(usually attached on left side).
If the headset is backwards, the
left/right position information
will be swapped.

2) See a service center as soon
as possible to inspect/correct
wiring. This wiring fault can
cause fail-safe audio not to
function.

“3D audio
left” message

1) Aircraft wired for
mono intercom

1) See a service center to wire the
installation for stereo headsets.

heard in left
ear only, no
audio heard in
right ear.

“3D audio
right” message
heard in right
ear only, no
audio heard in

1) Incorrect aircraft
wiring (right channel
used for mono
instead of left, or left/
right swapped)

1) See a service center as soon
as possible to inspect/correct
wiring. This wiring fault can
cause fail-safe audio not to
function.

left ear

3D Audio Troubleshooting

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GMA 350 Audio Panel

CLEARANCE RECORDER AND PLAYER

The GMA 350 contains a digital clearance recorder that records up to

2.5 minutes of the selected COM radio signal. Recorded COM audio is
stored in separate memory blocks. Once 2.5 minutes of recording time
have been reached, the recorder begins recording over the stored memory
blocks, starting from the oldest block.

Pressing the PLAY Key once plays the latest recorded memory block. The
Play function can also be accessed via Voice Recognition commands. Refer
to the ‘Voice Recognition’ section for more information.

Pressing the

MKR/MUTE

Key during play of a memory block stops play.
If a COM signal is detected during play of a recorded memory block, play
is halted.

Pressing the PLAY Key while audio is playing begins playing the previously
recorded memory block. Each subsequent press of the PLAY Key selects
the previously recorded memory block.

Powering off the unit automatically clears all recorded blocks.

Stops Play

Marker Mute Key

VOICE RECOGNITION

Voice Recognition allows the pilot (and optionally copilot) to control the
GMA 350 using spoken commands. To activate Voice Recognition, push
and hold the Push-to-Command (PTC) button while speaking a command.
When the Push-to-Command button is released, the GMA 350 will respond.

If a command is correctly interpreted by the GMA 350, a positive
acknowledgement chime will be played, and the pilot should verify that the
correct button selection is indicated by the triangular annunciator lights.
Alternatively, some commands will be indicated by a voice response from
the GMA 350. If the desired modes are not indicated by annunciator lights
or a voice response, the pilot should repeat the command by using the
Push-to-Command button, or by manually using the front panel controls
of the GMA 350.

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GMA 350 Audio Panel

If a command is incorrectly interpreted by the GMA 350, a negative
acknowledgement tone will be played. The pilot should repeat the
command by using the Push-to-Command button, or by manually using the
front panel controls of the GMA 350. In the evenet of any abnormal Voice
Recoginition operation, the front panel controls may be used to override
Voice Recognition and manually control the GMA 350.

The following table lists the available Voice Recognition commands, the
associated actions, and the voice response if applicable:

Control Example Phrase Action

“COM one” Toggles COM1 audio
“MIC one” Selects MIC1/COM1 audio
“COM one MIC” Selects MIC1/COM1 audio
“COM two” Toggles COM2 audio
“MIC two” Selects MIC2/COM2 audio
“COM two MIC” Selects MIC2/COM2 audio
“Split COM” Selects split COM mode

COM

“Monitored COM mute” OR
“Mute Monitored COM”

Mutes monitored COM on
primary COM reception (refer to
Page 8).

Voice Response: “Monitor mute
enabled”.

“Disable monitored COM mute”
“Monitored COM mute disable”
“Disable mute monitored COM”

OR
“Mute monitored COM disable”

Disables monitored COM mute
on primary COM reception (refer
to Page 8).

Voice Response: “Monitored
mute disabled”.

“NAV one” Toggles NAV1 audio

NAV

“NAV two” Toggles NAV2 audio

AUX “AUX” OR “Auxiliary” Toggles AUX audio

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25

GMA 350 Audio Panel

Control Example Phrase Action

“Telephone”
“Phone” OR

Toggles (TEL/JACK) input

“Jack”
“Telephone mute”

“Mute telephone”
“Phone mute”
“Mute phone”
“Jack mute”
OR

Mutes TEL/JACK on radio
reception.

Voice Response: “Tel and jack
mute enabled”.

“Mute Jack”
“Disable telephone mute”

“Mute telephone disable”
“Disable phone mute”
“Mute phone disable”
“Disable jack mute”
“Mute jack disable”
“Telephone mute disable”
“Disable mute telephone”
“Phone mute disable”

Disables TEL/JACK mute on radio
reception.

Voice Response: “Tel and jack
mute disabled”.

“Disable mute phone”
“Jack mute disable”
OR
“Disable mute jack”

“MUSIC one” Toggles MUS1 input
“MUSIC two” Toggles MUS2 input

Mutes MUS1 on radio reception
Voice Response: “Music one

mute enabled”

Disables MUS1 mute on radio
reception.

Voice Response: “Music one
mute disabled”.

MUSIC

“MUSIC one mute”
OR
“Mute MUSIC one”

“Disable MUSIC one mute”
“MUSIC one mute disable”
“Disable mute MUSIC one”
OR
“Mute MUSIC one disable”

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Garmin GMA 350 Pilot’s Guide

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GMA 350 Audio Panel

Control Example Phrase Action

Mutes MUS2 on radio reception.
Voice Response: “Music two

mute enabled”.

Disables MUS2 mute on radio
reception.

Voice Response: “Music two
mute disabled”.

MUSIC

“MUSIC two mute” OR
“Mute MUSIC two”

“Disable MUSIC two mute”
“MUSIC two mute disable”
“Disable mute MUSIC two”
OR
“Mute MUSIC two disable”

“Pilot” Toggles PILOT button
“Copilot” Toggles COPLT button

ICS Isolation

“Passenger” OR
“Pass”

“Passenger mute”
“Pass mute”
“Mute passenger”
OR
“Mute pass”

Toggles PASS button

Mutes passengers during radio
reception.

Voice Response: “Passenger
mute enabled”.

“Disable passenger mute”
“Disable pass mute”
“Disable mute passenger”
“Disable mute pass”
“Passenger mute disable”
“Pass mute disable”
“Mute passenger disable”

Disables muting of passengers
during radio reception.

Voice Response: “Passenger
mute disabled”.

OR
“Mute pass disable”

Configures Copilot as a
“Copilot is passenger” OR
“Copilot is pass”

Copilot

Configuration

“Copilot is crew”

passenger.

Voice Response: “Copilot is

passenger”.

Configures Copilot as flight

crew.

Voice Response: “Copilot is

crew”.

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Garmin GMA 350 Pilot’s Guide

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GMA 350 Audio Panel

Control Example Phrase Action

“Manual squelch” OR
“Man squelch”

Toggles manual squelch mode

“Manual squelch threshold up”

Manual
Squelch

“Man squelch threshold up”
“Manual squelch volume up”
OR

“Man squelch volume up”

Increases manual squelch
threshold

“Manual squelch threshold
down”
“Man squelch threshold down”
“Manual squelch voume down”

Decreases manual squelch

threshold
OR
“Man squelch volume down”

NOTE: Finer manual squelch adjustment may be made using the dual concentric knobs
on the GMA 350. The voice command “Up” or “Down” is equivalent to three clicks of
the inner knob.

Speaker (SPKR) “Speaker” Toggles SPKR on/off

PA “P - A” Toggles PA on/off

Marker Beacon

(MKR/MUTE)

COM Clearance

Recorder

Cursor

Volume

Adjustments

“Marker”
“Mute marker” OR
“Marker mute”

“Play”
“Read back” OR
“Say again”

“Cursor off”
“Cursor cancel” OR
“Cancel cursor”

“(Desired selection*) volume
up”

“(Desired selection*) volume
down”

Same action as pressing MKR/

MUTE (refer to page 4).

Same action as pressing PLAY

(refer to page 5).

Cancels cursor when cursor is

flashing

Increases volume of desired

selection

Decreases volume of desired

selection

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Garmin GMA 350 Pilot’s Guide

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GMA 350 Audio Panel

Control Example Phrase Action
Volume

Adjustments

“(Desired selection*) volume

Displays the current volume but
does not change it

* Desired selection = “Speaker”, “pilot”, “copilot”, “passenger”, “pass”, “marker”,
“aux”, “auxiliary”, “telephone”, “phone”, “jack”, “music one”, or “music two”.

NOTE: Finer volume adjustment may be made using the dual concentric knobs on the
GMA 350. The voice command “Up” or “Down” is equivalent to three clicks of the
inner knob.

“Distribute telephone to (desired
position(s) **)”
OR

Distribution
(Blue Mode)

“Distribute phone to (desired
position(s) **)”
OR
“Distribute jack to (desired

Distributes TEL/JACK to desired
positions.

position(s) **)”
“Distribute music one to (desired

position(s) **)”
“Distribute music two to (desired

position(s)**)”

Distributes MUS1 to desired
position(s)

Distributes MUS2 to desired
position(s)

** Desired position(s) = “All”, “none”, “pilot”, “copilot”, “passenger”, “pass”, or any
combination of pilot, copilot, passenger, or pass.
NOTE: The word “to” may be omitted from distribution phrases.

Enables 3D audio (refer to page

“Three-D audio”

21)
Voice Response: “Three-D audio

left, three-D audio right”

3D Audio

Enables standard audio (disables

“Standard audio”

3D audio)
Voice Response: “Standard

Audio”

Voice Recognition Commands

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Garmin GMA 350 Pilot’s Guide

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GMA 350 Audio Panel

ENTERTAINMENT INPUTS

The GMA 350 provides three stereo telephone/entertainment inputs:

•The telephone/entertainment ( ) Key controls a telephone or
entertainment device connected to the rear of the audio panel or to the
Front Panel Jack.

•The MUS1 and MUS2 Key controls the Entertainment Music audio
input.

The Front Panel Jack can be used as an entertainment input or a telephone

input (in which case, it operates simultaneously with the rear telephone
interface). The Front Panel Jack is a 3.5-mm stereo jack that is compatible
with popular portable entertainment devices such as MP3s, CD players,
and cell phones. The headphone outputs of the entertainment devices are
plugged into the Front Panel Jack.

Distribution of the entertainment inputs are configured in Blue-Select

Mode.

TELEPHONE AND ENTERTAINMENT MUTING

Telephone and entertainment muting can be enabled or disabled by the

user, however it is always muted during alerts.

Enabling/Disabling Muting

Press and hold the

to toggle muting on and off. The aural message “Mute Music on

Reception Enabled/Disabled” or “Mute Tel and Jack on Reception
Enabled/Disabled” is heard.

MUS1, MUS2

, or ( ) Key for two seconds

FAIL-SAFE OPERATION

If there is a failure of the GMA 350 or when power is not applied, a

fail-safe circuit connects the pilot’s headset and microphone directly to the
COM1 transceiver. Audio is not available on the speaker during Fail-safe
operation.

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Garmin GMA 350 Pilot’s Guide

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GMA 350 Audio Panel

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Garmin GMA 350 Pilot’s Guide

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Garmin International, Inc.

1200 East 151st Street

Olathe, KS 66062, U.S.A.

Toll free: 800.800.1020 or

866.739.5687

p: 913.397.8200

f: 913.397.8282

Garmin AT, Inc.

2345 Turner Road SE

Salem, OR 97302, U.S.A.

Toll free: 800.525.6726

p: 503.391.3411

f: 503.364.2138

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Liberty House, Bulls Copse Road

Hounsdown Business Park

Southampton, SO40 9RB, U.K.

Toll free (within U.K.) 0808.2380000

p: 44/0870.8501241

f: 44/0870.8501251

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No. 68, Jangshu 2nd Road
Shijr, Taipei County, Taiwan

p: 886/2.2642.9199

f: 886/2.2642.9099

© 2011 Garmin Ltd. or its subsidiaries

www.garmin.com

190-01134-12 Rev. D