Channel Guard
Channel Guard encode is transmitted on analog clear channels only. Channel
Guard decode will operate on either a clear or private channel. The exception
is when GE
•
STAR signaling is used (see GE
•
STAR paragraph).
GE
•
STAR
When GE
•
STAR is programmed on a private channel, the radio will trans-
mit GE
•
STAR in clear mode and then switch to private for the voice portion
of the call. If GE
•
STAR is sent with Channel Guard, then both are sent in
clear mode and then radio switches to private mode. Emergency GE
•
STAR
data burst is transmitted in clear mode.
DUAL CONTROL OPERATION
The ORION mobile radio may be programmed to operate from two separate
Control Units. This permits radio operation from two separate locations in
the vehicle. Dual control operation is available in both trunked and conven-
tional modes. Only one control unit can control the mobile radio unit at a
time. The control unit which controls the radio operation is called the active
controller and the second unit is called the idle controller.
Switching Control
Control can be switched to the idle controller by pressing the push-to-talk
(PTT) on the microphone associated with the idle controller. Once PTT is
pressed, the radio will switch control to the idle controller unless the active
controller is currently transmitting (i.e., PTT pressed on active controller), in
which case the switch will not occur. When control is switched to the idle
controller, two short high-pitched tones will sound at the controller where
PTT was pressed to indicate that the idle controller is now the active control-
ler and the previous active controller is now the idle controller.
Control Switching Modes
The radio can be pre-programmed for two modes of dual operation, Slaved
and Independent. In the Slaved mode the two controllers will use the same
radio System and Group settings. The Independent mode permits each con-
troller to have its own saved System and Group settings.
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