Garmin 347 Manual

GMA 347
audio panel pilot’s guide
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Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. A
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.
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Garmin GMA 347 Pilot’s Guide190-00325-00 Rev. A
1
COPYRIGHT
Copyright © 2005 Garmin Ltd. or its subsidiaries. All rights reserved.
This manual reflects the operation of Software version 2.08. Some differences in operation may be observed when comparing the information in this manual 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., Unit 5, The Quadrangle, Abbey Park Industrial Estate, Romsey, Hampshire S051 9DL, U.K.
Tel: [phone] Fax: [phone]
Garmin Corporation, No. 68, Jangshu 2nd Road, Shijr, Taipei County, Taiwan
Tel: [phone] Fax: [phone]
Web Site 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.
June 2005 Printed in the U.S.A.
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Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. A
2
Layout
Marker Beacon
Indicators
Marker Beacon
Hi/Lo Sensitivity Transmit Receive Keys
Com Receiver
Keys Nav Receiver Keys
Marker Mute
Key
Telephone and Speaker
Keys Intercom Isolation Keys
Recording Playback
Key
Split Com
Key
Pilot’s Squelch
Knob
Copilot/Passenger
Volume Knob
Copilot/Passenger
Squelch Knob
Pilot’s Volume
Knob
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Garmin GMA 347 Pilot’s Guide190-00325-00 Rev. A 3
Layout
Transceiver selection keys. Selects the COM trans-
mitter and associated receiver.
Split COM operation key. When active, the Pilot
uses the COM 1 transceiver and the Copilot uses
COM 2.
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.
COM Playback key. Pressing this key plays back
the most recent 2-1/2 minutes of received COM.
Marker Beacon System. Annunciators, Marker
Mute key, Marker Sense key and Hi Sense LED.
Marker Mute key also turns ON/OFF Music Mut-
ing and halts COM playback.
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.
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.
Nav receiver keys. Pressing a Nav receiver key
selects the receiver. Pressing again deselects
the receiver.
Pulling the right volume knob controls passenger
volume, pushing in controls Copilot volume. Copi-
lot and passenger share the (outer) squelch knob.
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Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. A
4
Description
INTRODUCTION
The Garmin GMA 347 is an audio control panel and mark-
er 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. MASQTM (Master Avionics Squelch) process-
ing reduces ambient noise from the avionics inputs.
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.
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Garmin GMA 347 Pilot’s Guide190-00325-00 Rev. A 5
Description
Microphones
The GMA 347 Audio Panel can accept up to six (6) micro-
phone inputs, allowing for a two-person crew and up to four
(4) passenger intercom stations in the aircraft.
NOTE: A push-to-talk (PTT) switch must be pressed
to transmit on a selected Transceiver.
Each microphone input has an automatic squelch thresh-
old. Manual squelch override and PTT keyed ICS operation
are also available. Each microphone has a dedicated VOX cir-
cuit to ensure that only the active microphone is heard when
squelch is broken.
Mono/Stereo Headsets
The unit can accommodate up to six (6) headsets (pilot,
copilot and up to four (4) passengers).
NOTE: The use of stereo headsets is highly recom-
mended. However, if monaural headsets are plugged
into stereo jacks the unit will not be damaged.
When wired correctly, the use of a monaural headset in a
stereo jack shorts the right headset channel to ground. Anyone
listening on a monaural headset hears only the left channel in
both ears. If a monaural headset is used at one of the passen-
ger positions, anyone else listening on a stereo headset hears
audio in the left ear only, unless their headset has a mono/ste-
reo switch set to mono.
NOTE: 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, failsafe operation will not work.
Intercom
The intercom system provides four modes of isolation:
Pilot, Copilot, Crew and All. In Pilot mode, the Pilot is isolated
from all other occupants of the aircraft. In Copilot mode, the
Copilot is isolated, while the Pilot and Passengers share the
intercom.
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Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. A
6
Description
In Crew Isolation mode, the Pilot and Copilot can commu-
nicate with each other while the passengers are able to com-
municate only with each other. In All mode, there is no isola-
tion and every occupant can communicate with every other
occupant.
The passengers cannot transmit over the active COM radio,
even if equipped with a PTT key.
UNMUTED/UNSWITCHED INPUTS
The unit provides four (4) unmuted/unswitched inputs that
are always present on the headsets or speakers. These inputs
are as follows:
• ALTITUDE WARNING
• UNSWITCHED 1
• UNSWITCHED 2
• UNSWITCHED 3
The unit may be configured with preset volume levels for
MUSIC 1, MUSIC 2, UNSWITCHED 1, UNSWITCHED 2,
UNSWITCHED 3 and ALTITUDE WARNING. See the
configuration table at the end of this manual. Contact a Garmin-
authorized service center for volume level adjustment.
COM MUTING
The COM muting on receive and COM muting on transmit
options are enabled in the Configuration mode.
COM Muting on Receive
The COM Muting on Receive option mutes all secondary
COM audio when a primary COM signal is detected.
When the COM muting on receive option is enabled, only
the primary COM radio audio is recorded by the digital clear-
ance recorder.
COM Muting on Transmit
The COM Muting on Transmit option mutes all secondary
COM audio while the primary COM radio is transmitting.
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Garmin GMA 347 Pilot’s Guide190-00325-00 Rev. A 7
Description
Telephone
The GMA 347 provides a 2-way telephone interface.
Operation depends on the state of the TEL key and ICS
mode. See the ICS Isolation Modes & Telephone Distribu-
tion table in the operation section of this manual. Tele-
phone communication is much like using the intercom,
allowing both parties to talk at once.
The TEL channel may be disabled in Configuration mode.
Contact a Garmin-authorized service center for details.
Auxiliary Entertainment Inputs
The GMA 347 provides two stereo entertainment inputs;
MUSIC 1 and MUSIC 2. Two 3.5 mm stereo phone jacks
should be installed in a convenient location for this purpose.
These inputs are compatible with popular portable entertain-
ment devices such as MP3 and CD players. The headphone
outputs of these devices are plugged into the MUSIC 1 or MU-
SIC 2 jacks.
Only the pilot and copilot hear MUSIC 1. MUSIC 2 is a
non-muted input heard only by the passengers. MUSIC 1 and
MUSIC 2 characteristics are affected by the active intercom
mode. Refer to the ICS Isolation Modes and Telephone Dis-
tribution table.
MUSIC 1 is always soft-muted when an interruption occurs
from an aircraft radio. Soft muting is the gradual return of
MUSIC 1 to its original volume level. When the MKR/MUTE
key is pressed and held for two seconds, the pilot hears two
beeps to indicate that MUSIC 1 muting by COM has been dis-
abled. Pressing and holding the MKR/MUTE key again for
two seconds sends one beep to the pilot to indicate COM mut-
ing is restored.
MUSIC 1 can also be configured to mute during ICS activ-
ity. Contact a Garmin-authorized service center to configure
MUSIC 1 muting by the ICS.
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Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. A
8
Operation
SYSTEM OPERATION
Multifunction Controls
The Pilot side volume knob controls the ON
and OFF function, the pilot’s intercom volume
plus manual and automatic squelch.
When pressed, manual squelch is selected and the MAN
SQ LED is ON indicating that squelch is adjusted manually.
When pressed again the MAN SQ LED turns OFF and squelch
is automatic.
The Copilot side volume knob controls the
Copilot and passenger intercom volume level.
The MKR/MUTE key selects marker audio
and “Smart Mutes” the marker signal. That is,
the marker tone is silenced, then waits for the
next marker tone. It also turns ON/OFF Music Muting, plus
cancels the COM audio playback.
The SPKR key turns the cabin speaker ON
and OFF. Pressing and holding for 2 seconds
selects PA mode. The SPKR key LED blinks
when PA is active.
Power ON/OFF
The GMA 347 may be powered ON and OFF with the
avionics master switch.
To control the ON and OFF function with the Pilot ICS
volume, rotate the knob clockwise out of the detent to turn
ON and counterclockwise into the detent to turn OFF.
During power-up, the unit undergoes a self-test, illuminat-
ing all panel annunciator lights for two (2) seconds. Once the
self-test is complete, the unit is ready for use with the same
keys selected when the system was last powered OFF.
Voice Recorder
The voice recorder feature records all the audio heard on
any selected COM radio. Recording begins automatically
unless the external RECORDER OFF function is activated.
Playback is heard by anyone listening on the selected radios.
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Garmin GMA 347 Pilot’s Guide190-00325-00 Rev. A 9
Operation
Pressing the PLAY key plays back the most
recent message. Pressing the PLAY key again
stops that message and skips to the next preceding
message. The MKR/MUTE key cancels the playback. In Split-
COM mode, the pilot’s or the copilot’s COM audio is recorded
and played back to the selected headset.
Transceivers
NOTE: Audio level is controlled by the selected COM
radio volume control.
Pressing COM1 MIC, COM2 MIC, or
COM3 MIC key selects the transmitter and
receiver audio for the selected transceiver source.
The active com audio is always heard on the head-
phones.
Also, each audio source can be selected
independently by pressing the COM1, COM2
or COM3 receiver keys. When selected this
way, they remain active as audio sources regardless of which
transceiver has been selected for microphone use.
When a microphone is keyed, the active transceiver’s MIC
key LED blinks approximately once per second indicating that
the radio is transmitting.
Split Com and PA Mode
Pressing the COM 1/2 key activates the Split
COM mode. In this mode the pilot uses COM
1 for MIC audio while the copilot uses COM
2. The pilot and copilot can transmit simul-
taneously over separate radios. The pilot can
still listen to COM 3, NAV 1, NAV 2, DME, ADF and MKR as
selected. The Split COM mode is cancelled by pressing the
COM 1/2 key a second time.
When in the Split COM mode the copilot may make PA
announcements while the pilot continues using COM 1 indepen-
dently. PA mode is entered by pressing and holding the SPKR
key for two seconds while in the Split COM mode. The copilot’s
voice is then heard over the cabin speaker when keyed. A second
press of the SPKR key returns the copilot to normal Split COM
operation.
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Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. A
10
Operation
When in PA mode, the SPKR LED blinks at a faster rate than
that of the COM MIC key indicators.
NOTE: Garmin makes no expressed or implied guar-
antees regarding the suitability of the Split COM
feature in any given installation.
Transmit Interlock
An aircraft installation with transmit-interlock activated op-
erates in the following way. When one or another transmitter
is keyed, all other receivers are cut off so that they won’t pick
up the active COM transmitter interference. This is the pre-
ferred option for single pilot operation.
For aircraft with two pilots aboard, transmit-interlock may
interfere with communications. When the pilot or the copilot
transmit, no audio is heard on any other receiver. This means
that if the pilot is communicating with ATC while the copilot
transmits on another radio, all pilot reception is lost during the
time of copilot transmission.
If the installation does not have transmit-interlock activat-
ed, all the receivers are listening all the time whether any radio
is transmitting or not. Split COM performance varies signifi-
cantly across installations. In small aircraft, interference is af-
fected by both the distance between antennas and the tuned
frequency separation.
If the transceivers interfere with each other, transmission by
one radio produces static or squeal, thus loss of communica-
tion from any other radio.
Split COM can be disabled in the Configuration mode.
Contact a Garmin-authorized service center for Split COM and
transmit-interlock configuration.
COM SWAP
A remote mounted pushbutton switch may be used to
transfer the active microphone between COM1 MIC and
COM2 MIC. Pressing the switch has no effect when COM3 or
Split COM is active.
Contact a Garmin-authorized service center for details on
the remote COM swap option.
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Garmin GMA 347 Pilot’s Guide190-00325-00 Rev. A 11
Operation
MARKER BEACON RECEIVER
The GMA 347 marker beacon receiver and
indicators are part of the ILS system. The mark-
er beacon lamps operate independently of any
audio selection and cannot be turned off. The
GMA 347 can drive external marker lamps if required and also
provides an autopilot middle marker sense output.
Prior to beginning an ILS approach, select high or low
marker sensitivity with the SENS key. The HI LED above the
SENS key illuminates for high sensitivity and remains off for
low sensitivity.
Pressing the MKR/MUTE key prior to an
approach allows the marker audio tones to be
heard in the headsets. When the MKR/MUTE
key illuminates, the marker audio will be heard.
Pressing the key again while audio is heard will mute the
marker audio until the next beacon is received.
Once the MKR/MUTE key is pressed, when a marker bea-
con tone is received, pressing the MKR/MUTE key during the
tone SmartMutes the audio. That is, the audio turns off and
returns when the next marker signal is received.
The marker beacon signal sensitivity threshold can be set
in Configuration mode. Contact a Garmin-authorized service
center for adjustment.
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Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. A
12
Operation
Mode PILOT
LED
COPLT
LED
TEL
LED Pilot Hears Copilot Hears Passenger
Hears Input to Phone
ALL
OFF OFF OFF
Selected radios;
pilot; copilot;
passengers;
MUSIC 1
Selected radios;
pilot; copilot;
passengers;
MUSIC 1
Selected radios;
pilot; copilot;
passengers;
MUSIC 2
None
OFF OFF ON
Selected radios;
pilot; copilot;
passengers;
MUSIC 1;
TEL audio
Selected radios;
pilot; copilot;
passengers;
MUSIC 1;
TEL audio
Selected radios;
pilot; copilot;
passengers;
MUSIC 2;
TEL audio
Pilot; copilot;
passengers
PILOT
ON OFF OFF Selected radios;
pilot
Copilot;
passengers;
MUSIC 1;
TEL audio
Copilot;
passengers;
MUSIC 2;
TEL audio
Copilot;
passengers
ON OFF ON Selected radios;
pilot; TEL audio
Copilot;
passengers;
MUSIC 1
Copilot;
passengers;
MUSIC 2
Pilot
ICS Isolation Modes & Telephone Distribution
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Garmin GMA 347 Pilot’s Guide190-00325-00 Rev. A 13
Operation
Mode PILOT
LED
COPLT
LED
TEL
LED Pilot Hears Copilot Hears Passenger Hears Input to Phone
COPILOT
OFF ON OFF
Selected radios;
pilot; passengers;
MUSIC 1
Copilot;
TEL audio
Selected radios;
pilot; passengers;
MUSIC 2
Copilot
OFF ON ON
Selected radios;
pilot; passengers;
MUSIC 1;
TEL audio
Copilot
Selected radios;
pilot; passengers;
MUSIC 2;
TEL audio
Pilot; passengers
CREW
ON ON OFF Selected radios;
pilot; copilot
Selected radios;
pilot; copilot
Passengers;
MUSIC 2;
TEL audio
Passengers
ON ON ON
Selected radios;
pilot; copilot;
TEL audio
Selected radios;
pilot; copilot;
TEL audio
Passengers;
MUSIC 2 Pilot; copilot
ICS Isolation Modes & Telephone Distribution (Cont’d)
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Garmin GMA 347 Pilot’s Guide 190-00325-00 Rev. A
14
Operation
GMA 347 PROGRAMMING OPTIONS
Programming options include variable configurations that
can be arranged by a Garmin authorized service center. Some
options include a crew operable pushbutton or toggle switch
or might be fixed configurations that are unchangeable by the
crew. Configurations include the following:
• Com Swap. An external pushbutton Swaps Com 1
MIC and Com 2 MIC.
• External Marker Beacon Lights. The GMA 347 can
drive another set of marker lamps on the instrument
panel.
• Marker Beacon Volume and sensitivity are adjustable.
• Deactivate MASQTM (master squelch). Software con-
figuration enables/disables master squelch. Level of
MASQTM is also adjustable.
• PA Muting option enables/disables PA output.
• Record Playback. Two separate options: An external
pushbutton activates voice recorder playback. Also,
the recorder can be controlled with a toggle switch to
enable/disable recording.
• Auxiliary audio. An external switch or software con-
figuration controls the auxiliary audio input.
• Enable or Disable Internal Sidetone. Software configu-
ration enables/disables Internal sidetone.
• Enable or Disable COM muting on transmit and COM
muting on receive. When configured this way, audio
on unselected COMs is muted while the selected COM
is transmitting or receiving audio.
• Pilot or Copilot COM recording. Either permanent
change or a toggle switch option, during the Split Com
mode, COM 1 or COM 2 audio can be selected for
voice recording and playback.
• Record COM 2. Allows recording of Copilot audio.
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Garmin GMA 347 Pilot’s Guide190-00325-00 Rev. A 15
Operation
• Pilot and Copilot MIC volume and speaker levels are
adjustable.
• ICS Muting option stops playing Music 1 during ICS
activity.
• Enable or disable DME and ADF Input.
• Enable or Disable Split COM function.
• Enable or Disable COM 3 function.
• Enable or Disable the telephone channel
• Enable or Disable Speaker function.
• Adjust the volume level of Music 1 and Music 2,
Unswitched 1, Unswitched 2, Unswitched 3 and Alti-
tude Warning
CAUTION: When the GMA 347 Audio panel is turned
OFF or inoperative, certain autopilots will not oper-
ate. No warning tone is supplied when the autopilot
disengages, and the middle marker sense signal is not
supplied.
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www.garmin.com
Garmin Corporation
No. 68, Jangshu 2nd Road
Shijr, Taipei County, Taiwan
p: 886/2.2642.9199 f: 886/2.2642.9099
Garmin International, Inc.
1200 East 151st Street
Olathe, KS 66062, U.S.A.
p: 913.397.8200 f: 913.397.8282
Garmin AT, Inc.
2345 Turner Road SE
Salem, OR 97302, U.S.A.
p: 503.391.3411 f: 503.364.2138
Garmin (Europe) Ltd.
Unit 5, The Quadrangle
Abbey Park Industrial Estate
Romsey, SO51 9DL, U.K.
p: 44/0870.8501241 f: 44/0870.8501251
190-00325-00 Rev. A © 2005 Garmin Ltd. or its subsidiaries
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