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scan for the priority system is defined by the System Sample Time control, located in the ProScan
Options dialog box. See Section 9.21.3 for more information on ProScan
9.21.3
ProScan
The radio may be programmed for ProScan system scan operation for multi-site applications depending
on the version of radio flash code. ProScan is an improved multi-site system scanning algorithm designed
to replace ProSound
™
scanning. ProScan provides the radio with the ability to select a new system for the
radio to communicate on, when the selected system drops below a predefined level. This is accomplished
by enabling each radio to analyze the signal quality of its current control channel and compares it with the
signal quality of the control channel for each site in its adjacent scan list. (The signal quality metric used
for the ProScan algorithm is based on a combination of both
R
eceived
S
ignal
S
trength
I
ndicator (
RSSI
)
and Control Channel Verification (CCV) measurements.) When the selected system degrades to a pre-
programmed level, the radio will begin to look for a better control channel. Once a control channel that
exceeds the pre-programmed parameters is found, the radio will change to the new system and emit a tone
(if enabled through programming). If the control channel is completely lost, the radio will enter Wide
Area System scanning and search the programmed adjacent systems until a suitable control channel is
found.
9.22 EMERGENCY OPERATION
The radio's ability to declare an emergency, clear an emergency, remain locked on an emergency system
and group, and the emergency audio and display freeze can each be enabled or disabled through
programming. When an emergency is declared scanning will stop and restarts only after the emergency
has been cleared.
9.22.1
Receive an Emergency Call
When receiving an Emergency Call on the selected group and system, an alert beep is heard and is
displayed. The message
*RXEMER*
flashes in the display on line two until the emergency condition is
cleared.
9.22.2
Declare an Emergency Call
To send an emergency call to a selected system and group (or on an optionally pre-programmed group):
1.
Press and hold the red EMERGENCY button that is on top of the radio in front of the antenna for
approximately one second (this time is programmable and therefore could be longer or shorter; check
with the system administrator). The radio will transmit an emergency call request with the radio ID
until an emergency channel assignment is received.
2.
When the working channel assignment is received, the radio sounds a single beep indicating the radio
has auto keyed (see Table 9-4) and is ready for voice transmission.
*TXEMER*
flashes on line two in
the display until the emergency is cleared.
3.
Press PTT and speak into the microphone in a normal voice. and momentarily turn ON.
4.
Release PTT when the transmission is complete.
9.22.3
Clear an Emergency Call
Check with your system administrator to ensure that your radio is configured with the
ability to clear an emergency.
