Tyco Electronics P5300 用户手册

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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 Received Signal Strength Indicator (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. 

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. 

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. 

Perform the following steps 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 9-3) 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.  

To clear the emergency first press and hold the   button. While continuing to hold the   button, press the 
EMERGENCY button. (This will work if the radio is programmed to clear emergencies.) 

When the radio receives an individual call (a call directed only to the user's radio), it un-mutes on the 

assigned working channel and displays  . The first line on the display shows the logical ID number of the 
unit sending the message, or the associated name if the ID number is found in the individual call list. The 
radio can be programmed to ring when an individual call is received. If enabled, the ring begins five 
seconds after the caller un-keys and will continue until the PTT button, the   button or the individual call 
mode is entered.