User Manual

SGD-SB2025NT-TUM, Part 2
Jan 12 Page 61 SOLAR COMMISSIONING
5.4.2.3 Site Deselection Timer (Minutes)
If an in-service base station Rx squelch is open for longer than this value, that station will be
removed from the Voter list until that squelch is closed continuously for a short time (typically
10 seconds). If invoked, the Station panel will still indicate a received RSSI level but not a voted
indication.
5.4.2.4 TM triggered Talk Through
T/T or repeat mode is implemented in the digital domain within the TM, no matter how the function
is controlled or initiated. The following options refer to the manner in which T/T may be enabled, in
addition to the external application of console/control switched facility through the Central NI. If no
Central NI is in use, the setting ‘Permanent’ will need to be used.
(a). ‘None’ . T/T operation is not enabled.
Note.
T/T is still available as a controlled function via the Central NI if enabled for operation
– see Section 5.2.2.4.
(b). ‘On Central NI Fail’ . Loss of communications between the corresponding Central NI and
the TM will cause T/T to be enabled.
(c). ‘Permanent’ . T/T is permanently enabled.
Note.
When the Control Tx Key function is active, T/T will be suspended, i.e. Control Tx Key
has precedence but will not switch off the T/T function.
5.4.3 Facilities
5.4.3.1 Tx Key Hang
The ‘Tx Key Hang (sec)’ is the time that the Tx PTT is maintained after the Tx Key command has
been removed either as a direct input to the Central NI or after cessation of a received signal when
the channel is operating on T/T. This setting is maintained by a Station NI that is operating in fall
back (Line Fail) T/T.
The range is from OFF (no delay) to 5 seconds (in 1 second increments).
5.4.3.2 CTCSS
A phase coherent CTCSS tone is available from a dedicated output on the Facilities connector of a
Station NI. The tone is generated at the NI from a value that is passed from the TM. The CTCSS
frequency is entered in Hertz in the range of 50 Hz to 300 Hz inclusive (in 0.1 Hz increments). A
value entered outside of this range will be corrected to the closest limit. Entering 0 Hz indicates
that no CTCSS tone is to be generated.
This setting is maintained by a Station NI that is operating in fall back (Line Fail) T/T.
5.5 C HANNEL S ETUP P25
For a P25 system, the ‘Channel Setup’ page is slightly different and is shown overleaf in
Figure 55 . It is still accessed in the same way via the ‘Setup’ button on the Channel Status Panel
of the TM ET main window as shown in Section 3.4.2 – Channel Status Panel .