Garmin GMA 347 User Manual

GMA 347

audio panel pilot’s guide

WARRANTY

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.

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.

Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. B

COPYRIGHT

Copyright © 2007 Garmin Ltd. or its subsidiaries. All rights reserved.

This manual reflects the operation of
to earlier or later software versions. Ask your installer for the Software version of your unit.

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

Garmin AT, Inc., 2345 Turner Road SE, Salem, OR 97302, U.S.A.
Tel: [phone] Fax [phone]

Garmin (Europe) Ltd., Liberty House, Bulls Copse Road, Hounsdown Business Park, Southampton, S040 9RB, U.K.
Tel: 44/ (0) 870.8501241 Fax: 44/ (0) 870.8501251

Garmin Corporation, No. 68, Jangshu 2nd Road, Shijr, Taipei County, Taiwan
Tel: [phone] Fax: [phone]

Website Address: www.garmin.com

Except as expressly provided herein, no part of this manual may be reproduced, copied, transmitted, disseminated, downloaded or stored in any storage medium,
for any purpose without the express written permission of Garmin. Garmin hereby grants permission to download a single copy of this manual and of any revision
to this manual onto a hard drive or other electronic storage medium to be viewed for personal use, provided that such electronic or printed copy of this manual or
revision must contain the complete text of this copyright notice and provided further that any unauthorized commercial distribution of this manual or any revision
hereto is strictly prohibited.

Garmin® is a registered trademark of Garmin Ltd. or its subsidiaries. These trademarks may not be used without the express permission of Garmin.

Software version 4.00 or later. Some differences in operation may be observed when comparing the information in this manual

November 2007 Printed in the U.S.A.

Garmin GMA 347 Pilot’s Guide190-00325-00 Rev. B

1

Layout

Pilot’s Squelch

Pilot’s Volume

Knob

Knob

Copilot/Passenger

Squelch Knob

Copilot/Passenger

Volume Knob

Marker Mute

Key

Marker Beacon

Indicators

Marker Beacon

Hi/Lo Sensitivity

2

Transmit Receive

Com Receiver

Keys

Keys

Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. B

Split Com

Key

Nav Receiver

Keys

Telephone and Speaker

Keys

Recording Playback

Key

Intercom Isolation

Keys

Layout

Volume/Squelch: Rotating the left (Pilot) volume
knob controls the ON and OFF function. (Full CCW
detent is OFF) Pressing the left volume knob
toggles between manual and automatic squelch.

Pulling the right volume knob controls passenger
volume, pushing in controls Copilot volume. Copilot
and passenger share the (outer) squelch knob.

COM receiver keys. Pressing a COM receiver key
selects the receiver, which is heard in addition to
the selected transceiver. Pressing again deselects
the receiver.

Transceiver selection keys. Selects the COM
transmitter and associated receiver.

Split COM operation key. When active, the Pilot
uses the COM 1 transceiver and the Copilot uses
COM 2.

COM Playback key. Pressing this key plays back
the most recent 2-1/2 minutes of received COM.

Nav receiver keys. Pressing a Nav receiver key
selects the receiver. Pressing again deselects
the receiver.

Selects telephone operation.

Selects cabin speaker. Press and hold 2 seconds
for PA mode. SPKR key blinks in PA mode.

Intercom isolation keys. Four modes
available.

Marker Beacon System. Annunciators, Marker
Mute key, Marker Sense key and Hi Sense LED.
Marker Mute key also turns ON/OFF Music
Muting and halts COM playback.

Garmin GMA 347 Pilot’s Guide190-00325-00 Rev. B

3

Description

INTRODUCTION

The Garmin GMA 347 is an audio control panel and marker
beacon system. Pushbutton keys control audio selection of
COM, NAV, telephone and intercom. With the exception of
the PLAY key, LED annunciators indicate when a key function
is selected. Annunciator brightness is adjusted automatically
by photocell dimming. LED-illuminated key brightness is
adjusted by the radio dimming bus control. A failsafe circuit
connects the pilot’s headset and microphone directly to COM 1
in case power is interrupted or the unit is turned off.

The GMA 347 includes a six-position intercom system
(ICS) with electronic cabin noise de-emphasis and two stereo
music inputs. Two volume controls, one for the pilot and a
combined copilot/passenger control, set intercom audio level.
The intercom provides four selectable modes of isolation (All,
Crew, Pilot, Copilot). A pilot-selectable cabin speaker output
is used to listen to selected aircraft radios or to broadcast
PA announcements. MASQ
processing reduces ambient noise from the avionics inputs.

TM

(Master Avionics Squelch)

Each microphone input has an automatic squelch threshold.

Manual squelch is available by pressing the Pilot side

VOL/SQ
knob. When the MAN SQ annunciation is lit the large squelch
knobs control pilot and copilot/passenger squelch threshold.
Turning either knob clockwise increases the squelch threshold
level, turning counterclockwise decreases the level.

The GMA 347 provides a digital recorder that can play back
two and a half minutes of COM audio. Recording is automatic
when a COM signal is received. Playback is controlled by
pressing the PLAY key or a remote mounted switch. Playback
can be stopped by pressing the

MKR/MUTE key.

Upon installation, the unit may be configured in various
ways depending on the aircraft type and the needs of the
pilot. See the configuration list at the end of this manual.
Contact a Garmin-authorized service center for details and
assistance in altering the configuration settings.

4

Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. B