Tone And Ctcss Operation - Kenwood TH-27A Instruction Manual

4-6-3_ Tone and CTCSS Operation
Some repeaters require the use of a control signal to
activate the repeater. Several different methods are
currently in use.
In the United States sub-audible tones are sometimes
used. 38 different Sub-audible frequencies are possible.
With the use of the optional CTCSS unit (TSU-7
*)
you
will be able to operate in a Tone Operated Squelch Mode.
When this option is installed and the CTCSS function has
been activated the radio will not open squelch until the
proper tone is received.
(*)
The CTCSS unit (TSU-7) is included with models
U.S.A and Canadian version.
In Europe and United Kingdom a 1750 Hz tone is used
in transmit. Press and hold the TONE key to transmit with
the access tone. you need not press the PTT switch.
Since this tone is required in Europe and the United
Kingdom a 1750 Hz tone encoder is included with
models delivered to these countries.
• Tone Frequency Selection
1. Press the F key. The F indicator will light. Press the
TONE/TONE SEL key within 10 seconds of pressing
the F key. The current tone frequency will show in the
display.
2. Rotate the Tuning control to select the desired tone
frequency.
3. When the desired tone frequency is selected. the
previous mode is resumed 10 seconds after selection
or when the TONE/TONE SEL key is pressed.
Tone Frequency (Hz)
67.0 82.5
97.4
114.8
136.5 162 .2 192.8 233.6
71 .9 85.4
100.0 118 .8 141.3 167.9 203.5 241.8
74.4 88.5
103.5 123.0 146.2 173.8 210.7 250.3
77.0 91.5 107.2
127.3 151.4 179.9 218 .1
79 .7 94.8 110.9 131 .8
156.7 186.2 225 .7
• Tone/CTCSS Operation
With the use of the CTCSS unit (TSU-7) the transceiver
will transmit the desired tone.
TONE:
Press the TONE key. The T indicator appears in the
display the transmitter will transmit the desired tone.
CTCSS:
Press the F key and then the 2/CTCSS key. The CT
indicator appears in the display the transceiver will
transmit the desired tone and will also operate in the
Tone Squelch mode. i.e. squelch will not open until the
proper tone is received as a portion of the incoming
receive signal.
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