Icom IC-M31 User manual

INSTRUCTION MANUAL
iM31
VHF MARINE TRANSCEIVER
New2001
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i
New2001
IN CASE OF EMERGENCY
If your vessel requires assistance, contact other vessels and
the Coast Guard by sending a distress call on Channel 16.
❍USING CHANNEL 16
DISTRESS CALL PROCEDURE
1. “MAYDAY MAYDAY MAYDAY.”
2. “THIS IS ...........................” (name of vessel)
3. Your call sign or other indication of the ves-
sel.
4. “LOCATED AT .....................” (your position)
5. The nature of the distress and assistance re-
quired.
6. Any other information which might facilitate
the rescue.
RECOMMENDATION
CLEAN THE TRANSCEIVER THOROUGHLY WITH FRESH
WATER after exposure to saltwater, and dry it before opera-
tion. Otherwise, the transceiver’s keys, switches and con-
trollers may become inoperable due to salt crystallization.
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ii
New2001
FOREWORD
Thank you for purchasing this Icom product. The IC-M31 VHF
MARINE TRANSCEIVER is designed and built with Icom’s state
of the art technology and craftsmanship. With proper care this
product should provide you with years of trouble-free operation.
IMPORTANT
READ ALL INSTRUCTIONS carefully and com-
pletely before using the transceiver.
SAVE THIS INSTRUCTION MANUAL—This in-
struction manual contains important operating instructions for
the IC-M31.
EXPLICIT DEFINITIONS
FEATURES
☞Waterproof construction
Built tough to withstand the punishing marine environ-
ment, the IC-M31 meets JIS waterproof specification
grade 7 while using BP-223 (option) or BP-224.
☞Dualwatch and tri-watch functions
Convenient functions which allow you to monitor the dis-
tress channel (Ch 16) while receiving a channel of your
choice—dual watch; or monitor the distress channel and
another channel while receiving a channel of your
choice—tri-watch.
☞Large, easy-to-read LCD
With dimensions of 16(H) ×32(W) mm, the IC-M31’s func-
tion display is easy to read and shows operating conditions
at a glance. Backlighting and contrast can be adjusted to
suit your preferences.
☞Simple operation
9 large buttons on the front panel provide user-friendly op-
eration. The independent volume and channel buttons are
located on the front panel for convenient one-hand opera-
tion.
WORD DEFINITION
RWARNING
CAUTION
NOTE
Personal injury, fire hazard or electric shock
may occur.
If disregarded, inconvenience only. No risk
of personal injury, fire or electric shock.
Equipment damage may occur.
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PRECAUTION
RWARNING! NEVER connect the transceiver to an
AC outlet. This may pose a fire hazard or result in an electric
shock.
RWARNING! NEVER hold the transceiver so that the
antenna is very close to, or touching exposed parts of the
body, especially the face or eyes, while transmitting. The
transceiver will perform best if the microphone is 5 to 10 cm
away from the lips and the transceiver is vertical.
NEVER connect the transceiver to a power source other
than the BP-223 or BP-224. Such a connection will ruin the
transceiver.
AVOID using or placing the transceiver in direct sunlight or
in areas with temperatures below –15°C or above +55°C.
KEEP the transceiver out of the reach of children.
KEEP the transceiver at least 0.9 meters away from your
vessel’s magnetic navigation compass.
BE CAREFUL! The transceiver’s right-side panel will
become hot when operating continuously for long periods.
BE CAREFUL! The IC-M31 employs waterproof con-
struction, which corresponds to JIS waterproof specification,
Grade 7 (1 m depth for 30 min.). However, once the trans-
ceiver has been dropped, waterproofing cannot be guaran-
teed due to the fact that the transceiver may be cracked, or
the waterproof seal damaged, etc.
MAKE SURE the flexible antenna, top panel and battery
pack are securely attached to the transceiver, and that the an-
tenna, top panel and battery pack are dry before attachment.
Exposing the inside of the transceiver to water will result in
serious damage to the transceiver.
iii
New2001
Icom, Icom Inc. and the logo are registered trademarks of Icom Incor-
porated (Japan) in the United States, the United Kingdom, Germany, France,
Spain, Russia and/or other countries.
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iv
New2001
IN CASE OF EMERGENCY ................................................ i
RECOMMENDATION ........................................................... i
FOREWORD ....................................................................... ii
IMPORTANT ........................................................................ ii
EXPLICIT DEFINITIONS ..................................................... ii
FEATURES .......................................................................... ii
PRECAUTION .................................................................... iii
TABLE OF CONTENTS ...................................................... iv
1 OPERATING RULES ...................................................... 1
2 SUPPLIED ACCESSORIES AND ATTACHMENTS.... 2–3
■Supplied accessories ................................................... 2
■Attachments ................................................................. 2
3 PANEL DESCRIPTION ............................................... 4–6
■Front, top and side panels............................................ 4
■Function display .......................................................... 5
4 BASIC OPERATION ................................................. 7–12
■Channel selection ........................................................ 7
■Adjusting the volume level ........................................... 9
■Adjusting the squelch level .......................................... 9
■Receiving and transmitting ........................................ 10
■Call channel programming ......................................... 11
■Lock function ............................................................. 12
■Automatic backlighting .............................................. 12
■Monitor function ......................................................... 12
5 SCAN OPERATION ................................................ 13–14
■Scan types ................................................................. 13
■Setting tag channels .................................................. 14
■Starting a scan .......................................................... 14
6 DUALWATCH/TRI-WATCH .......................................... 15
■Description ................................................................ 15
■Operation ................................................................... 15
7 SET MODE ............................................................. 16–20
■SET mode programming ........................................... 16
■SET mode items ........................................................ 17
8 BATTERY CHARGING ........................................... 21–24
■Battery charging ........................................................ 21
■Battery cautions ......................................................... 21
■Optional battery case ................................................ 22
■Optional battery chargers .......................................... 23
9 OPTIONAL SWIVEL BELT CLIP ........................... 25–26
■MB-87 contents ......................................................... 25
■To attach .................................................................... 25
■To detach ................................................................... 26
10 TROUBLESHOOTING ................................................ 27
11 CHANNEL LIST ........................................................... 28
12 SPECIFICATIONS AND OPTIONS .............................. 29
13 DOC.............................................................................. 30
TABLE OF CONTENTS
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1
OPERATING RULES
New2001
1
DPriorities
• Read all rules and regulations pertaining to priorities and
keep an up-to-date copy handy. Safety and distress calls
take priority over all others.
• You must monitor Channel 16 when you are not operating
on another channel.
• False or fraudulent distress calls are prohibited under law.
DPrivacy
• Information overheard but not intended for you cannot law-
fully be used in any way.
• Indecent or profane language is prohibited.
DRadio licenses
(1) SHIP STATION LICENSE
When your craft is equipped with a VHF FM transceiver, you
must have a current radio station license before using the
transceiver. It is unlawful to operate a ship station which is not
licensed.
Inquire through your dealer or the appropriate government
agency for a Ship-Radiotelephone license. This license in-
cludes the call sign which is your craft’s identification for radio
purposes.
(2) OPERATOR’S LICENSE
A restricted Radiotelephone Operator Permit is the license
most often held by small vessel radio operators when a radio
is not required for safety purposes.
The Restricted Radiotelephone Operator Permit must be
posted near the transceiver or be kept with the operator. Only
a licensed radio operator may operate a transceiver.
However, non-licensed individuals may talk over a transceiver
if a licensed operator starts, supervises, ends the call and
makes the necessary log entries.
A current copy of the applicable government rules and regu-
lations is only required to be on hand for vessels in which a
radio telephone is compulsory. However, even if you are not
required to have these on hand it is your responsibility to be
thoroughly acquainted with all pertinent rules and regulations.
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2
2
SUPPLIED ACCESSORIES AND ATTACHMENTS
1
2
■Supplied accessories
The following accessories are supplied: Qty.
• Flexible antenna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
• Handstrap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
• Belt clip (MB-68) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
• Ni-Cd battery pack (BP-224) . . . . . . . . . . . . . . . . . . . . . . 1
• Battery charger (BC-150) . . . . . . . . . . . . . . . . . . . . . . . . . 1
• Screws for the BC-150 (M3.5 ×20) . . . . . . . . . . . . . . . . . 2
• AC adapter (BC-147E)*1. . . . . . . . . . . . . . . . . . . . . . . . . . 1
• Top panel/Top sheet (double-sided tape)*2. . . . . . . . . 1 set
*1Not supplied with some versions.
*2Use the top panel with top sheet as a spare. Ask your dealer for
details.
■Attachments
DFlexible antenna
Connect the supplied flexible an-
tenna to the antenna connector.
CAUTION!
• NEVER HOLD by the antenna
when carrying the transceiver.
•Transmitting without an an-
tenna may damage the trans-
ceiver.
DHandstrap
Pass the handstrap through
the loop on the side of the
transceiver as illustrated at
right. Facilitates carrying.
DBelt clip
Attach the belt clip to the transceiver as illustrated below.
To attach the belt clip
To remove the belt clip
Top panel
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3
2SUPPLIED ACCESSORIES AND ATTACHMENTS
New2001
ïBattery pack
To remove the battery pack:
Turn the screw counterclockwise, then pull the battery pack
in the direction of the arrow as shown below.
To attach the battery pack:
Insert the battery pack in the IC-M31 completely, then turn the
screw clockwise.
NEVER remove or insert the battery pack when the trans-
ceiver is wet or soiled. This may result water or dust get-
ting into the transceiver/battery pack and may result in the
transceiver being damaged.
NOTE: When removing or attaching the battery pack, use
a coin or flat-blade screwdriver to loosen or tighten the bot-
tom screw.
CAUTION!:
When attaching or removing a battery pack, make sure the
rubber seal is set in the groove of the battery pack cor-
rectly. If the seal is not neatly in the groove it may be dam-
aged when attaching the battery pack.
If the seal is damaged, waterproofing is not guaranteed.
OPEN
LOCK
Screw position
when removing battery
OPEN
LOCK
Screw position
when attaching battery
Make sure both the rubber seal (purple) is set to the groove
correctly and dust or else does not adhere to it.
Battery pack Battery pack
Rubber seal
Groove
Correct position Incorrect position
NOTE:
When attaching a battery pack, make sure dust or else does
not adhere to the rubber seal. If dust or else is on the seal
when attaching a battery pack, the water resistant may be
reduced.
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4
3
PANEL DESCRIPTION
2
3
■Front, top and side panels
qPOWER SWITCH [PWR]
Push and hold to turn power ON and OFF.
wANTENNA CONNECTOR (p. 2)
Connects the supplied antenna.
eSCAN/DUAL KEY [SCN•DUAL]
•Starts and stops normal or priority scan. (p. 14)
•Enters watch mode when pushed for 1 sec. (p. 15)
•Exits watch mode when pushed during watch operation.
(p. 15)
rTRANSMIT POWER/LOCK KEY [H/L•LOCK]
•Selects high or low power when pushed. (p. 10)
•Toggles the lock function ON/OFF when pushed for 1
sec. (p. 12)
tVOLUME UP/DOWN KEYS [+]/[–]•[VOL]
•Adjusts the volume level. (p. 9)
•After pushing [SQL•MONI], push to adjust the squelch
level. (p. 9)
ySQUELCH KEY [SQL•MONI]
•Push this key, then adjust the squelch level with [+]/[–].
(p. 9)
•Manually opens the squelch for monitoring the channel
while pushed and held. (p. 12)
•While pushing this key, turn power ON to enter the set
mode. (p. 16)
☞Continue to the next page.
r
q
o
u
i
!0
w
y
t
e
Microphone
Function display
(p. 5)
Speaker
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5
3PANEL DESCRIPTION
New2001
■Front, top and side panels (Continued)
uCHANNEL UP/DOWN KEYS [YY]/[ZZ]•[TAG]
•Selects an operating channel. (pgs. 7, 8)
•Selects the SET mode condition of the item. (p. 16)
•Checks tag channels or changes scanning direction dur-
ing scan. (p. 14)
•Sets or clears the displayed channel as a tag (scanned)
channel when pushed both keys for 1 sec. (p. 14)
•While pushing this key, turn power ON to clear all tag
channels in the channel group. (p. 14)
iDIAL/CHANNEL GROUP KEY [DIAL]
•Push to return to the channel selection before selecting
the channel 16 or the call channel with [16•C].
•Selects one of 2 regular channel groups in sequence
when pushed for 1 sec. (p. 8)
- International, U.S.A.*1(or ATIS*2) channels are available.
*1Available for the UK version only
*2Available for the German version only
oCHANNEL 16 KEY [16•C]
•Selects Channel 16 when pushed. (p. 7)
•Selects the call channel when pushed for 1 sec. (p. 7)
•Enters call channel programming condition when the call
channel is selected and this key is pushed for 3 sec.
(p. 11)
•Exits set mode when pushed during set mode operation.
(p. 16)
!0 PTT SWITCH [PTT]
Push and hold to transmit; release to receive.
■Function display
qTRANSMIT INDICATOR (p. 10)
Appears while transmitting.
wBUSY INDICATOR
Appears when receiving a signal or when the squelch
opens. (p. 10)
“”blinks while monitoring. (p. 12)
eTAG CHANNEL INDICATOR (p. 14)
Appears when a tag channel is selected.
rCALL CHANNEL INDICATOR (p. 7)
Appears when the call channel is selected.
qe
ryt
w
!5 !3!4
i
u
o
!2
!1
!0
!7
!6
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6
3
PANEL DESCRIPTION
New2001
tLOCK INDICATOR (p. 12)
Appears while the lock function is activated.
yBATTERY INDICATOR
Indicates remaining battery power.
uSCAN INDICATOR (p. 14)
Blinks while scanning.
iDUALWATCH/TRI-WATCH INDICATORS (p. 15)
“DUAL”appears during dualwatch; “TRI”appears during
tri-watch.
oDUPLEX INDICATOR
Appears when a duplex channel is selected.
!0 SUB CHANNEL READOUT
•Indicates Channel 16 during priority scan, dualwatch or
tri-watch. (p. 15)
•Indicates the SET mode item while in SET mode. (p. 16)
•Indicates the squelch level while squelch setting. (p. 9)
•Indicates the volume level while volume setting. (p. 9)
!1 SQUELCH LEVEL INDICATOR
Shows the squelch level.
!2 VOLUME LEVEL INDICATOR
Shows the volume level.
!3 VOLUME LEVEL ADJUSTING INDICATOR
Blinks while adjusting the volume level.
!4 SQUELCH LEVEL ADJUSTING INDICATOR
Blinks while adjusting the squelch level.
!5 CHANNEL NUMBER READOUT
•Indicates the selected operating channel number.
•In SET mode, indicates the selected condition.
!6 CHANNEL GROUP INDICATOR (p. 8)
“I”appears when International; “U”appears when U.S.A.
(U.K. version only); “ATIS”appears when the channel
group in which ATIS function is activated (German version
only).
!7 LOW POWER INDICATOR (p. 10)
•“LOW”appears when low power is selected.
•“LOW”blinks when switching forced low power mode be-
cause of a high temperature error or low voltage.
Indication
Full Middle Charging
required No battery
Battery level
blinks when the battery is exhaustion.
blinks when the battery over charged.
3
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BASIC OPERATION
New2001New2001
4
■Channel selection
IMPORTANT!: Prior to using the transceiver for the first
time, the battery pack must be fully charged for optimum
life and operation. To avoid damage to the transceiver, turn
the power OFF while charging.
DChannel 16
Channel 16 (Distress channel) is used for establishing initial
contact with another station and for emergency communica-
tions. Channel 16 is automatically monitored during both du-
alwatch and tri-watch. While standing by, you must monitor
Channel 16.
qPush [16•C] to select Channel 16.
wPush [DIAL] to return to the condition before selecting
Channel 16, or push [Y]/[Z] to select the operating chan-
nel.
DCall channel
Each regular channel group has a separate call channel. In
addition, the call channel is monitored during tri-watch. The
call channels can be re-programmed (p. 11) and are used to
store your most often used channels in each channel group
for quick recall.
qPush [16•C] for 1 sec. to select the call channel in the se-
lected channel group.
•“CALL”and the call channel number appear.
•Each channel group may have its own call channel after pro-
gramming a call channel. See the “Call channel programming”
on p. 11 for details.
wPush [DIAL] to return to the condition before selecting the
call channel, or push [Y]/[Z] to select the operating chan-
nel.
Channel 16 is the default setting.
(depending on version)
C
Push
for 1 sec.
C
Push
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New2001
8
4
BASIC OPERATION
DInternational, U.S.A.*1and ATIS*2channels
There are 57 (58)*1International, 58 U.S.A.*1and 57 ATIS*2
channels. These channel groups may be specified for the op-
erating area.
qPush [DIAL] to select a regular channel.
wPush [Y]/[Z] to select a channel.
•“DUP”appears for duplex channels.
eTo change the channel group, push [DIAL] for 1 sec.
•International, U.S.A.*1and ATIS*2channels can be selected in
sequence.
*1Available for the UK version only
*2Available for the German version only
U.S.A channels*1
International channels
ATIS channels*2
Push
for 1 sec.
Push
for 1 sec.
4
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9
4BASIC OPERATION
New2001
■Adjusting the volume level
The volume level can be adjusted with [+]/[–].
➥Push [+]/[–] to adjust the volume level.
•“VOL”indicator starts blinking.
•There are 32 volume levels to choose.
•When no key is pushed for 5 sec., the transceiver returns to nor-
mal condition.
■Adjusting the squelch level
The IC-M31 has a squelch level adjustment, even though there
is no control knob for it. In order to receive signals properly, as
well as for the scan to function effectively, the squelch must be
adjusted to the proper level.
qPush [SQL•MONI], then adjust the squelch level with [+]/[–].
- “SQL”indicator starts blinking.
- There are 11 squelch levels to choose from: “OP”is completely
open; “10”is tight squelch; “1”is loose squelch level.
- When no key is pushed for 5 sec., the transceiver returns to nor-
mal condition.
wPush [SQL•MONI] again to return to normal condition.
✔ CONVENIENT!
The squelch level adjustment key can be selected from
[Y]/[Z] and [+]/[–] with following operation.
•While pushing both [SQL•MONI] and [Y], turn the power ON
to set [Y]/[Z] to the squelch level adjustment key.
•While pushing both [SQL•MONI] and [+], turn the power ON
to set [+]/[–] to the squelch level adjustment key.
Blinks during squelch
level adjustment.
Indicates the
squelch level.
Blinks during volume
level adjustment.
Indicates the
volume level.
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4
BASIC OPERATION
New2001
■Receiving and transmitting
qPush and hold [PWR] to turn power ON.
wSet the volume and squelch levels.
➥Push [SQL•MONI], and push [–] to open the squelch.
➥Push [SQL•MONI] to stop “SQL”indicator blinking, then
push [+]/[–] to set the volume level.
➥Push [SQL•MONI], and push [+]/[–] to set the squelch
level.
ePush [Y]/[Z] to select the desired channel.
- When receiving a signal, “”appears and audio is emitted
from the speaker.
- Further adjustment of the volume may be necessary at this point.
rPush [H/L•LOCK] to select the output power if necessary.
- “LOW”appears when low power is selected; no indication when
high power is selected.
- Choose low power to conserve battery power, choose high
power for longer distance communications.
- Some channels are for low power only.
tPush and hold [PTT] to transmit, then speak into the
microphone.
- “”appears.
- Channel 70 cannot be used for transmission.
yRelease [PTT] to receive.
IMPORTANT: To maximize the readability of your trans-
mitted signal, pause a few sec. after pushing [PTT], hold
the microphone 5 to 10 cm from your mouth and speak
into the microphone at a normal voice level.
NOTE: The transceiver has a power save function to con-
serve the battery power. The power save function activates
automatically when no signal is received for 5 sec.
qPower ON
eSet channel
tPush to
transmit
yRelease to
receive rSet output
power
wSet volume
wSet the
squelch level
wSet the squelch
level
Microphone
CAUTION: Transmitting without an antenna may
damage the transceiver. 4
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11
4BASIC OPERATION
New2001
■Call channel programming
The call channel key is used to select the default channel,
however, you can program your most often-used channel in
each channel group for quick recall.
qPush [DIAL] for 1 sec. several
times to select the desired chan-
nel group (INT, USA, ATIS) to be
programmed.
wPush [16•C] for 1 sec. to select the
call channel.
•“CALL”and call channel number ap-
pear.
ePush [16•C] again for 3 sec. (until
a long beep changes to 2 short
beeps) to enter call channel pro-
gramming condition.
•Call channel number to be pro-
grammed flashes.
rPush [Y]/[Z] to select the desired
channel.
tPush [16•C] to program the dis-
played channel as the call chan-
nel.
•The call channel number stop flash-
ing.
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12
4
BASIC OPERATION
New2001
■Lock function
This function electronically locks all keys (except for [+]/[–],
[PTT], [SQL•MONI] and [H/L•LOCK]) to prevent accidental
channel changes and function access.
➥Push [H/L•LOCK] for 1 sec. to turn the lock function ON
and OFF.
■Automatic backlighting
This function is convenient for nighttime operation. The auto-
matic backlighting can be activated in SET mode. (p. 18)
➥Push any key except for [PTT] to turn the backlighting ON.
•The backlighting is automatically turned OFF after 5 sec. of in-
activity.
■Monitor function
The monitor function releases the noise squelch mute. See
p. 18 for details of the monitor switch action.
➥Push [SQL•MONI] for 1 sec. to activate the monitor func-
tion.
•“ ”blinks and audio is emitted.
MONI
Push
for 1 sec.
Blinks while the monitor
function is used.
LOCK
Push
for 1 sec.
Appears while the
lock function is used.
4
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13
SCAN OPERATION
New2001
5
■Scan types
Scanning is an efficient way to locate signals quickly over a
wide frequency range. The transceiver has priority scan and
normal scan.
In addition, an auto scan function is available for standby
convenience.
Set the tag channels (scanned channel) before scanning.
Clear the tag channels which inconveniently stop scanning,
such as digital communications.
Choose priority or normal scan in SET mode. (p. 17)
PRIORITY SCAN
Priority scan searches through all tag channels in sequence
while monitoring Channel 16. When a signal is detected on
Channel 16, scan pauses until the signal disappears; when
a signal is detected on a channel other than Channel 16,
scan becomes dualwatch until the signal disappears.
CH 88
CH 01
CH 16
CH 02
CH 05 CH 04
CH 03
NORMAL SCAN
Normal scan, like priority scan, searches through all tag
channels in sequence. However, unlike priority scan, Chan-
nel 16 is not checked unless Channel 16 is set as a tag
channel.
CH 01 CH 02
CH 88
CH 05 CH 04
CH 03
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5
SCAN OPERATION
New2001
■Setting tag channels
For more efficient scanning, add desired channels as tag
channels or clear the tag for unwanted channels. Non-tag
channels will be skipped during scanning.
Tag channels can be assigned to each channel group (INT,
USA, ATIS) independently. (Depending on version)
qSelect the desired channel group (INT, USA, ATIS) by
pushing [DIAL] for 1 sec., if desired.
wSelect the desired channel to set as a tag channel.
ePush both [Y] and [Z] for 1 sec. to set the displayed chan-
nel as a tag channel.
•“ ”appears in the function display.
rTo cancel the tag channel setting, push both [Y] and [Z]
for 1 sec.
•“ ”disappears.
✔Clearing all tag channels in the selected channel group
While pushing and holding both [Y] and [Z], turn power ON
to clear all tag channels in the channel group.
■Starting a scan
Set the priority scan function, scan resume timer and auto
scan function in advance, using SET mode. (pgs. 17, 18)
qSelect the desired channel group (INT, USA, ATIS) by
pushing [DIAL] for 1 sec., if desired. (Available for the UK
and German version only)
wPush [SCN•DUAL] to start priority or normal scan.
•“SCAN”blinks in the function display.
•“16”appears on the sub channel readout during priority scan.
•When a signal is received, scan pauses until the signal disap-
pears or resumes after pausing 5 sec. according to scan resume
timer setting. (Channel 16 is still monitored during priority scan.)
•Push [Y]/[Z] to check the scanning tag channels, change the
scanning direction or resume the scan manually.
eTo stop the scan, push [SCN•DUAL].
•“SCAN”disappears.
•Pushing [PTT], [16•C] or [DIAL] also stops the scan.
5
Scan starts.
DUAL DUAL
Push Push
to stop the scan
Receiving a signal
and audio is emitted.
[Example]: Starting a normal scan.
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15
DUALWATCH/TRI-WATCH
New2001New2001
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■Description
Dualwatch monitors Channel 16 while you are receiving
another channel; tri-watch monitors Channel 16 and the call
channel while receiving another channel.
■Operation
qSelect the desired operating channel.
wPush [SCN•DUAL] for 1 sec. to start dualwatch or tri-watch
(depending on SET mode setting).
•“DUAL”blinks during dualwatch; “TRI”blinks during tri-watch.
•A beep tone sounds when a signal is received on Channel 16.
•Tri-watch becomes dualwatch when receiving a signal on the call
channel.
eTo cancel dualwatch/tri-watch, push [SCN•DUAL] again.
DUALWATCH/TRI-WATCH SIMULATION
•If a signal is received on Channel 16, dualwatch/tri-watch
pauses on Channel 16 until the signal disappears.
•If a signal is received on the call channel during tri-watch,
tri-watch becomes dualwatch until the signal disappears.
•To transmit on the selected channel during dualwatch/tri-
watch, push and hold [PTT].
Dualwatch Tri-watch
Call channel
[Example]: Operating tri-watch on INT channel 07.
Tri-watch starts.
Push
for 1 sec.
Signal is received
on the call channel.
Signal received on
Channel 16 takes
priority.
Tri-watch resumes
after the signal
disappears.
DUAL
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