Subaudible Tone Operation; I Tone Squelch - Icom IC-T81A Instruction Manual

I 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.

SUBAUDIBLE TONE OPERATION

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
[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
67.0
69.3
71.9
74.4
*CTCSS stands for continuous tone coded squelch system.
[DIAL] (or push
79.7 94.8 110.9 131.8 156.7 171.3 186.2 203.5 229.1
82.5 97.4 114.8 136.5 159.8 173.8 189.9 206.5 233.6
85.4 100.0 118.8 141.3 162.2 177.3 192.8 210.7 241.8
88.5 103.5 123.0 146.2 165.5 179.9 196.6 218.1 250.3
9
SET MODE
USING
T SQL
T SQL
(unit: Hz)
25