Alinco DR-635 - Manual (Page 44)

Many repeaters require a CTCSS tone or a DCS encode setting as a “key” to access a repeater
system, or a receiver using CTCSS or DCS squelch, so-called “selective-calling”. Sometimes,
CTCSS or DCS decode features are used on the output of a repeater so they can be used to open a
squelch. In this mode, regardless of the main squelch status, the audio can be heard ONLY when
the matching tone/code signal is received. The combination of CTCSS squelch and DCS function
is not available; only one or the other may be used for a given frequency.
Selective Communication
Tone-squelch (CTCSS) and DCS
1.
Press TS/DCS key. The current setting will be
displayed with T/SQ/DCS icons and relative
frequency/code. Press the same key to select
T/SQ/DCS setting.
2.
The numbers (such as 88.5) represent the
CTCSS frequency in Hz. When it is displayed
with the T icon only, the unit transmits the sub-
audible tone while the PTT is pressed (encode)
and the repeater access is enabled (assuming
the repeater is using 88.5).
3.
Press the same key again so that the SQ icon
shows up on the display. This is the CTCSS
decode frequency. This enables CTCSS squelch
(or Tone Squelch, TSQ).
4.
Press it again so that the 3-digit number and
DCS icon is displayed. This is the DCS code,
and it enables DCS encoding and decoding.
For 2-4, rotate the main dial or press the UP/DOWN keys to change the tone or the code. Press any
key (Except TS/DCS, or Mic UP/DOWN keys) to enter the setting and return to the original status.
The T/SQ/DCS icon will remain on the display to show the current status. To exit, simply use the
TS/DCS key and press it until the relative status icon T/TQ/DCS disappears.
The CTCSS encoding and decoding frequencies may be set differently. The encode setting fre-
quency automatically relates to the decode setting, but the decode setting does not affect encode.
The standard set of 38 different CTCSS tones are available as shown on the chart below. DCS
encode/decode cannot be separated and are selectable from 105 codes as shown below and on the
following page.
T
88.5
T/SQ
88.5
DCS
023
The original status
67.0 71.9 74.4 77.0 79.7 82.5 85.4 88.5
91.5 94.8 97.4 100.0 103.5 107.2 110.9 114.8
118.8 123.0 127.3 131.8 136.5 141.3 146.2 151.4
156.7 162.2 167.9 173.8 179.9 186.2 192.8 203.5
210.7 218.1 225.7 233.6 241.8 250.3
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