GME TX3340 - Manual (Page 18)

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CtCss & DCs
CTCSS (Continuous Tone Coded Squelch System)
ctcss is a squelch quieting system that allows several groups
of users to share the same channel without disturbing each
other. it uses one of a set of sub-audible (very low frequency)
tones to open and close the squelch on your radio.
there are two ctcss tone sets, one comprising 50 tones and
the other comprising 38 tones. Both tone sets are installed in
the tX3340 to ensure compatibility with other radio systems.
For more details, see CTCSS Tone Frequency Chart on
page 23.
to toggle between the ctcss 50 tone set and the ctcss 38
tone set:
1. switch the radio off.
2. Press and hold the SQL key while switching the radio
on again.
3. ctc50 or ctc38 will be displayed indicating which tone set
has been selected.
NOTE: When switching from ctc38 to ctc50 the radio will
retain the currently selected ctcss tone but will update the
associated tone set number to reflect its new location in the
ctc50 tone set table.
e.g. ctcss tone frequency of 233.6 hz is tone #36 in the
ctc38 tone set table but changes to tone #47 when
ctc50 is selected.
When switching down from ctc50 to ctc38, if there is no
equivalent ctc38 tone frequency the ctcss tone will be set to
oF and you will need to reselect a new tone.
DCS (Digitally Coded Squelch)
dcs is a squelch quieting system similar to ctcss, that uses
low frequency digital signals instead of one continuous low
frequency tone. As with ctcss, it also allows several user
groups to share the same channels without disturbing each
other. there are 104 dcs codes available. see DCS Tone
Chart on page 24.
Selecting a CTCSS or DCS tone
choosing which tone to use will probably be dependent on
the other radios you talk to. if you talk to others outside your
group who already use ctcss or dcs tones, you will need
to select the tone set and frequency that matches theirs. the
tX3340 includes most of the commonly used tone sets.
if the users you talk to don’t currently use ctcss or dcs
you can make your own choice. there is no difference in
performance or function between the different tone sets.
To select a CTCSS or DCS tone
NOTE: When selecting tones, ctcss tones are prefixed with
‘ctc’ and dcs tones are prefixed with ‘dc’.
1. Press and hold the MENU key until the radio beeps.
2. Briefly press the MENU key repeatedly until ‘ctcxx’ or
‘dcxxx’ is displayed (where xx represents a tone number in
the ctcss/dcs tone Frequency chart).
3. Press the or keys to scroll through the tone list and
select the required ctcss or dcs tone. scroll upwards for
dcs tones and downwards for ctcss tones.
if you wish to view the ctcss frequency or dcs tone instead
of the table number, briefly press the PRI key. to return to
the table code briefly press the PRI key again or wait for it
to time-out.
4. to disable ctcss or dcs tones altogether scroll to the
bottom of the list and select ‘ctcoF’.
5. to store the setting, press and hold the MENU key until the
radio beeps.