Garmin GMA 345 3-COM Manual

GMA 345 3-COM
pilot’s guide

Copyright © 2018 Garmin Ltd. or its subsidiaries. All rights reserved.
This manual reflects the operation of GMA 345 3-COM 3-COM units. 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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February, 2018 190-01878-05 Rev. A Printed in the U.S.A.

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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.

Transmitter Grant of Equipment Authorization
FCC
Contains FCC ID: QOQWT32I
This device complies with Part 15 of the FCC Rules. Operation is subject to the
following two conditions: (1) this device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
FCC RF Radiation Exposure Statement:
This equipment complies with FCC radiation exposure limits set forth for an uncontrolled
environment. End users must follow the specific operating instructions for satisfying
RF exposure compliance. This transmitter meets both portable and mobile limits as
demonstrated in the RF Exposure Analysis. This transmitter must not be co-located or
operating in conjunction with any other antenna or transmitter except in accordance
with FCC multi-transmitter product procedures.
IC
Contains IC: 5123A-BGTWT32I
NOTE
This device complies with Innovation, Science and Economic Development Canada
license-exempt RSS standard(s). Operation is subject to the following two conditions:
(1) this device may not cause interference, and (2) this device must accept any
interference, including interference that may cause undesired operation of the device.
Cet appareil est conforme aux normes RSS sans licence du ministére Innovation,
Sciences et Développement économique Canada. Son fonctionnement est soumis aux
deux conditions suivantes : (1) ce périphérique ne doit pas causer d’interférences et
(2) doit accepter toute interférence, y compris les interférences pouvant entraîner un
fonctionnement indésirable de l’appareil.

Anatel Warning
Este equipamento não tem direito ã proteção contra interferência prejudicial e não
pode causar interferência em sistemas devidamente autorizados.
Declaration of Conformity
Hereby, Garmin declares that this product is in compliance with the Directive
2014/53/EU. The full text of the EU declaration of conformity is available at the
following internet address: www.garmin.com/compliance.
Radio frequency/protocol: Bluetooth®wireless technology 2.4 GHz @ -0.49 dBm
nominal
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Part Number Change Summary
190-01878-05 Initial release
Rev Date Description
A February, 2018 Production Release

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 8
Table of Contents
Power-Up ...............................................................................................................................................10
Mono/Stereo Headsets...........................................................................................................................10
Left/Right Knobs ....................................................................................................................................10
Transceivers ...........................................................................................................................................12
Split-COM Mode ........................................................................................................................12
Transmit Indications ...................................................................................................................12
Enabling/Disabling Monitored COM Muting ..............................................................................13
Receivers................................................................................................................................................15
Nav Receiver ..............................................................................................................................15
Auxiliary Inputs ..........................................................................................................................15
Marker Beacon Receiver.............................................................................................................15
Turning Marker Beacon Audio On...................................................................................16
Muting Marker Beacon Audio.........................................................................................16
Deselecting Marker Beacon Audio..................................................................................17
Intercom System (ICS)............................................................................................................................17
Pilot Isolate Mode ..........................................................................................................17
Crew Isolate Mode .........................................................................................................18
Intercom Volume ........................................................................................................................18
Radio Mute Music ......................................................................................................................18
ICS Mute Music..........................................................................................................................18
Passenger Muting.......................................................................................................................19
Speaker ......................................................................................................................................19
Passenger Address Mode (PA Mode) ..............................................................................19
Split-PA Mode.................................................................................................................19
3D Audio................................................................................................................................................20
Enabling 3D Audio......................................................................................................................21
Clearance Recorder and Player ..............................................................................................................23
Entertainment Inputs .............................................................................................................................24
Music Effects..............................................................................................................................26
Entertainment Muting................................................................................................................26
Enabling/Disabling Muting .............................................................................................26
Bluetooth®.................................................................................................................................26
Pairing a Bluetooth Device .............................................................................................27
Pairing to a Garmin VIRB X or VIRB XE Action Camera...................................................28
Pairing To A Third-Party Camera......................................................................................28
Disabling Bluetooth........................................................................................................29
Bluetooth Media Controls ..............................................................................................29
Bluetooth Telephone Volume Controls............................................................................29
USB Power Jack......................................................................................................................................30
Fail-Safe Operation ................................................................................................................................31

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 9
GMA 345 3-COM Audio Panel
FEATURES AND OPERATION
The GMA 345 3-COM 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, a COM
clearance recorder, USB power jack, and Bluetooth®audio. 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. Intercom squelch threshold adjustments are handled automatically by
the system.
Pushbutton keys control audio selection. When a key is selected, a green
annunciator on 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.
GMA 345 3-COM
USB Jack Type ABluetooth Annunciator
Ambient Light Sensor Marker Beacon Lights

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 10
GMA 345 3-COM Audio Panel
NOTE: The 2-COM version of the GMA 345 (below) is described in the
GMA 345 Pilot’s Guide (Part Number: 190-01878-01).
GMA 345 (2-COM) User Interface
POWER-UP
The GMA 345 3-COM 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.
MONO/STEREO HEADSETS
Stereo headsets are recommended when using the GMA 345 3-COM.
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.
LEFT/RIGHT KNOBS
The Left Inner Knob powers-off the unit, and is used to control left
seat crew member ICS volume. The Left Outer Knob controls left seat
crew member music volume. The Right Inner Knob controls right seat
crew member ICS volume. The Right Outer Knob controls the right seat
crew member music volume. The seat considered the pilot position is
configurable for either left or right depending on the aircraft’s needs and is
set during installation. Passenger ICS and music volume is adjusted by the
knobs on the side associated with copilot.

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 11
GMA 345 3-COM Audio Panel
Right Knob - Right Seat Crew
Member Volume Controls
Left Knob - Left Seat Crew Member
Volume Controls
Right
Inner
Knob
Left
Outer
Knob
Left
Inner
Knob
Right
Outer
Knob
Function Action Visual/Tactile
Feedback Aural Feedback
Power OFF
Audio Panel
Turn Left Inner
Knob to full
counter-clockwise
position
All backlight
and annunciator
LEDs turn off
Left Inner Knob
clicks
Left seat crew
member ICS
Volume
Turn Left Inner
Knob right/left to
increase/decrease
volume
Minimum/maximum
volume is reached at
full counter-clockwise/
clockwise position
Left seat crew
member ICS
volume increases/
decreases
Left seat crew
member Music
Volume
Turn Left Outer
Knob right/left to
increase/decrease
volume
Minimum/maximum
volume is reached at
full counter-clockwise/
clockwise position
Left seat crew
member Music
volume increases/
decreases
Right seat
crew member
ICS Volume
Turn Right Inner
Knob right/left to
increase/decrease
volume
Minimum/maximum
volume is reached at
full counter-clockwise/
clockwise position
Right seat crew
member ICS
volume increases/
decreases
Right seat
crew member
Music Volume
Turn Right Outer
Knob right/left to
increase/decrease
volume
Minimum/maximum
volume is reached at
full counter-clockwise/
clockwise position
Right seat crew
member Music
Volume increases/
decreases
Left/Right Knob Functions

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 12
GMA 345 3-COM Audio Panel
TRANSCEIVERS
Audio from the #1, #2, or #3 COM receiver can be selected independently
by pressing the respective Key(s) ( COM1 , COM2 , or COM3 ). Pressing
COM1 MIC , COM2 MIC , or COM3 MIC selects the #1, #2, or #3 transmitter
and simultaneously selects the related COM receiver ( COM1 , COM2 , or
COM3 ) allowing received audio to be heard. The other COM receivers can
be added by pressing their respective keys.
By default, while transmitting on a COM channel (as selected with the
COM1 MIC , COM2 MIC , and COM3 MIC keys), both the transmitting and
receiving audio are heard on the COM channel. The GMA 345 3-COM
can be configured to instead mute receiving audio on a transmitting COM
channel. A Garmin authorized service center can make changes to the
default configuration.
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. The pilot uses the lower numbered
COM and the copilot uses the higher numbered COM.
Pressing two MIC Keys simultaneously initiates Split-COM Mode (i.e.,
COM1/COM2, COM1/COM3, or COM2/COM3). The respective COM
receive and MIC annunciators are illuminated indicating Split-COM
operation. Split-COM operation is cancelled by pressing one of the
selected MIC Keys again.
TRANSMIT INDICATIONS
During COM transmission, the active transceiver (COM1 MIC, COM2
MIC, or COM3 MIC) Key Annunciator flashes approximately once per
second.

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 13
GMA 345 3-COM Audio Panel
During Split-COM transmission, the lower numbered COM MIC
annunciator flashes when the pilot’s microphone PTT is pressed. The
higher numbered COM MIC annunciator flashes when the copilot’s
microphone PTT is pressed.
ENABLING/DISABLING MONITORED COM MUTING
Press and hold COM1 , COM2 , or COM3 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.
Function Action Key Annunciations
COM Selection: Toggle
between COM enabled
and COM disabled (the
audio from the current
MIC selected COM is
always enabled and
cannot be disabled).
Press the
corresponding COM
Key. COM
Enabled COM Disabled
MIC Selection: Selects
the COM used to
transmit during Push-to-
Talk (PTT).
Press the
corresponding MIC
Key. The last MIC
pressed remains
selected and
deselects all others.
MIC Enabled MIC Disabled
Transmit Indication:
Audio is sent from the
corresponding Crew MIC
to the selected COM. *
Push-to-Talk (PTT)
keyed.
MIC in-key
annunciator flashes.

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 14
GMA 345 3-COM Audio Panel
Function Action Key Annunciations
Split-COM Modes: The
pilot transmits on the
lower numbered COM
and the copilot transmits
on the higher numbered
COM independently.
Simultaneously
press COM1 MIC
and COM2 MIC
keys.
Simultaneously
press COM1 MIC
and COM3 MIC
keys.
Simultaneously
press COM2 MIC
and COM3 MIC
keys.
* The pilot has priority when transmitting in the case that both crew members attempt to transmit
on the same COM.
Transceiver Key Functions

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 15
GMA 345 3-COM Audio Panel
RECEIVERS
NAV RECEIVER
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
AUXILIARY INPUTS
The GMA 345 3-COM has 3 AUX inputs. A single AUX Key selects all
three AUX inputs to be simultaneously heard.
Selecting Auxiliary Inputs
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.
HI SENS AnnunciatorMarker Beacon Key & Lamps

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 16
GMA 345 3-COM Audio Panel
The marker beacon signal sensitivity threshold can be set to either a
regular or high sensitivity. To toggle between the two, press and hold the
MKR/MUTE Key for one second. The HI SENS annunciator illuminates
when signal sensitivity is set to high.
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 345 3-COM 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.
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.

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 17
GMA 345 3-COM Audio Panel
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.
INTERCOM SYSTEM (ICS)
The GMA 345 3-COM includes a three-position intercom system (ICS),
two MUSIC inputs, and one telephone/entertainment input for the pilot,
copilot and passengers. The intercom provides Pilot and Crew audio
isolation.
Intercom Controls
NOTE: The PILOT and CREW ICS ISOLATION states are exclusive. Both
cannot be active at the same time. When neither Pilot or Crew are
active, the unit is in All ICS mode. In this mode, the pilot, copilot, and
passengers communicate with each other.
NOTE: The left/right seat positions associated with ‘Pilot’ and ‘Copilot’
are configured during installation for the aircraft’s specific needs.
PiloT isolaTe Mode
Pressing the PILOT ‘ICS ISOLATION’ Key isolates the pilot from all
other ICS positions (copilot and passengers). The copilot and passengers
share communication between themselves but cannot communicate
with the pilot. A solid annunciation of the in-key annunciator indicates
PILOT ICS ISOLATION is active.

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 18
GMA 345 3-COM Audio Panel
crew isolaTe Mode
Pressing the CREW ‘ICS ISOLATION’ Key places the pilot and copilot
on a common ICS communication channel. The passengers are on their
own intercom channel and can communicate with each other, but
cannot communicate with the pilot and copilot. A solid annunciation
of the inkey annunciator indicates CREW ICS ISOLATION is active.
INTERCOM VOLUME
The knobs on either side of the GMA 345 3-COM control intercom and
music volume independently. The left inner and outer knobs control the
audio levels for the left seat crew member headset; the right inner and
outer knobs control audio levels for the right seat crew member headset.
Passenger volumes are shared with the side configured for copilot
operation. The inner, smaller knobs on both sides are used to control
intercom volume for the receiving headsets. The outer, larger knobs are
used to control music volume.
The left inner knob can be used to turn off the GMA 345 3-COM
audio panel, by turning fully counter-clockwise until the knob clicks. All
backlight and annunciator LEDs will turn off.
The position marks on all four knobs are not night-time visible.
RADIO MUTE MUSIC
Press and hold the NAV1 Key to enable or disable muting of music
channel 1, music channel 2 and Bluetooth music audio when radio (i.e.,
COM, NAV, or AUX) audio is active.
ICS MUTE MUSIC
Press and hold the AUX Key to enable or disable muting of music audio
when intercom audio is active.

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 19
GMA 345 3-COM Audio Panel
PASSENGER MUTING
Press and hold NAV2 to enable/disable passenger muting during COM
audio reception. The aural message “Passenger Mute Enabled/Disabled”
is heard.
SPEAKER
NOTE: Speaker audio turns off in circumstances where aircraft power
falls below 11 volts.
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
Passenger address Mode (Pa Mode)
Press and hold the SPKR Key for one second 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 “Push-
to-Talk” button to deliver announcements over the speaker and to the
passenger headsets.
sPliT-Pa Mode
During Split-PA Mode the pilot can continue to use COM1 or COM2
for transmission while the copilot delivers PA announcements. To
initiate Split-PA Mode, first enter Split-COM Mode by pressing any two
MIC Keys simultaneously, then press and hold the SPKR Key for one
second.

190-01878-05 Rev. A
Garmin GMA 345 3-COM Pilot’s Guide 20
GMA 345 3-COM Audio Panel
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 all three COMs are selected,
the listener hears the audio sources at the 11, 12 and 1 o’clock positions
with the COM numbers increasing clockwise. If two COMs are selected,
the listener hears the audio sources at the 11 and 1 o’clock positions with
the COM numbers increasing clockwise. All other intercom positions are
processed to sound like their relative seat location. By default, the GMA
345 3-COM assumes the pilot sits in the left seat. A Garmin authorized
service center can make changes to the default configuration.