Operating Manual Part 15

October 2008 5300 ES Series Mobile Radio Operating Manual 5-5
Conventional Features
5.4.4 Selective Squelch Code Select (CTCSS / DSC / NAC)
This feature allows the normal transmit and receive Call Guard (CTCSS/DCS/NAC)
programming to be temporarily overridden with a code selected from a preprogrammed
list. It is available if the SQ LIST option switch and a CTCSS/NAC code list have been
programmed. It is also selectable via the menu.
In addition, with the Handheld Control Unit (HHC) only, conventional systems can be
programmed for the Keypad CTCSS/DSC feature. Codes can then be selected directly
from the table by pressing the key for the code. For example, to select code 3 from the
table, simply press the “3” key. No other conventional mode functions can then be
assigned to these keys.
The CTCSS/DCS/NAC list is programmed with up to 64 tone (CTCSS) or digital (DCS)
Call Guard codes. Different codes can be programmed for the transmit and receive modes,
and carrier squelch (selective squelch disabled) can be programmed if desired. In addition,
each position can be programmed with an NAC code for use with P25 operation.
When the Call Guard code is changed using this feature, it remains selected even if other
channels are selected. However, if radio power is cycled or a talk-around channel is
selected, the normal codes are reselected. When scanning, the selected code also applies to
all scanned channels. Each channel can also be programmed to always ignore the code
selected from this list and use the default code instead.
If both analog and digital (Project 25) channels can be selected or scanned, the CTCSS/
DCS code for the selected position is used for analog channels and the NAC code for the
selected position is used for P25 channels. If a channel is programmed for mixed mode
operation, the selective squelch type (analog or digital) programmed for the transmit mode
determines the selective squelch type used.
Note Call Guard codes may be permanently reprogrammed by keypad programming (see
Section 5.14).
Proceed as follows to select a code using the SQ LIST option switch:
1 Press the SQ LIST option switch and then rotate the Select switch to select the desired
position. The display indicates “SEL SQ xx” where, “xx” is the selected code from 1-
64. The code number and actual code are alternately displayed (NACs are displayed in
hexadecimal).
2 To select the displayed code and return to the normal display, press the SQ LIST
(Squelch Code Select) switch again.
3 To check which code is selected, press the SQ LIST option switch once to display the
current selection and then again to return to normal operation.
4 To return to the normal selective squelch codes, select “DEFAULT” in this mode. As
previously described, the normal codes are also automatically reselected whenever
radio power is cycled or a talk-around channel is selected.