Tone Squelch Operation - Icom IC-440 Instruction Manual

6

TONE SQUELCH OPERATION

■ Tone squelch operation
The transceiver is equipped with 51 CTCSS tone frequencies,
104 DTCS codes. CTCSS/DTCS operation provides com-
munication with silent standby since you will only receive calls
from group members using the same CTCSS tone frequency/
DTCS code.
NOTE: Channels 5 and 35 are used for the emergency
channels, and CTCSS/DTCS operation is not available on
these channels.
D Setting CTCSS tone frequency/
DTCS code
q Select the desired channel except for channels 5 and 35.
(p. 14)
w Push and hold
e Push
F * or MONI
T SQL
SET
r Push
SCAN *
to toggle the CTCSS tone frequency/DTCS
TAG
code setting mode.
t Push
or
quency/DTCS code.
y Push and hold
push and hold
*Regardless of the assigned key function.
26
F for 2 sec. to enter set mode.
(Set Mode)
SET
* several times until "C" appears.
to set the desired CTCSS tone fre-
for 2 sec. to turn the power OFF, or
F for 2 sec. to exit set mode.
(Set Mode)
SET
CTCSS tone setting mode
List number (grey line)
CTCSS tone freqnency
• Available CTCSS tone frequency list
No. Freq.
[
01 67.0
02 69.3
03 71.0
04 71.9
05 74.4
06 77.0
07 79.7
08 82.5
09 85.4
10 88.5
11 91.5
NOTE: The transceiver has 51 tone frequencies and con-
sequently their spacing is narrow compared with units
having 38 tones. Therefore, some tone frequencies may
receive interference from adjacent tone frequencies.
DTCS code setting mode
List number (grey line)
No. Freq. No. Freq. No.
12 94.8 23 136.5 34
13 97.4 24 141.3 35
14 100.0 25 146.2 36
15 103.5 26 151.4 37
16 107.2 27 156.7 38
17 110.9 28 159.8 39
18 114.8 29 162.2 40
19 118.8 30 165.5 41
20 123.0 31 167.9 42
21 127.3 32 171.3 43
22 131.8 33 173.8 44
DTCS code
(Hz)
Freq. No. Freq.
177.3 45 218.1
179.9 46 225.7
183.5 47 229.1
186.2 48 233.6
189.9 49 241.8
192.8 50 250.3
196.6 51 254.1
199.5
203.5
206.5
210.7