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25
9
SUBAUDIBLE TONE OPERATION
■
Tone squelch
The tone squelch opens only when receiving a signal con-
taining a matching subaudible tone. You can silently wait for
calls from group members using the same tone.
➀
Set the operating frequency.
➁
Set the desired subaudible tone in set mode (see right).
➂
Push [MULTI] to enter subaudible tone mode.
• “T” appears; if “D” appears, push [MULTI(
↕
)] to select “T.”
➃
Push [MULTI(
↔
)] (or rotate [DIAL]) one or more times until
“TSQL” appears; then push [VFO] to exit set mode.
➄
When the received signal includes a matching tone,
squelch opens and the signal can be heard.
• When the received signal’s tone does not match, tone squelch
does not open, however, the S-indicator shows signal strength.
• To open the squelch manually, push and hold [SQL].
➅
Operate the transceiver in the normal way.
➆
To cancel the tone squelch, repeat steps
➂
and
➃
so that
no tone indicator appears.
☞
NOTE:
Some tone frequencies may receive interference
from adjacent tone frequencies.
✔
CONVENIENT
Store subaudible tone frequencies and tone squelch on/off
settings in memories (call) for easy recall.
D
Setting subaudible tones for
tone squelch operation (CTCSS* tones)
Separate tone frequencies can be set for tone squelch oper-
ation than for repeater operation (the same range of tones is
available—see below).
➀
Select VFO or a memory channel.
➁
Push [MULTI] for 1 sec. to enter set
mode.
➂
Push [MULTI(
↕
)] one or more times
until “CT” appears.
➃
Rotate [DIAL] (or push
[MULTI(
↔
)]) to select the a sub-
audible tone.
➄
Push [VFO] to program the se-
lected tone and exit set mode.
Available subaudible tone frequencies
(unit: Hz)
67.0
79.7
94.8 110.9 131.8 156.7 171.3 186.2 203.5 229.1
69.3
82.5
97.4 114.8 136.5 159.8 173.8 189.9 206.5 233.6
71.9
85.4 100.0 118.8 141.3 162.2 177.3 192.8 210.7 241.8
74.4
88.5 103.5 123.0 146.2 165.5 179.9 196.6 218.1 250.3
USING
SET MODE
T SQL
T SQL
*CTCSS stands for continuous tone coded squelch system.
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