E F Johnson Company 2425M80 Benutzerhandbuch

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Draft 02 - Sep 1 2015
4-8
Radio Wide Features
4.9
Microphone Off-Hook Detect
The microphone hanger can be connected to chassis ground and the radio programmed to 
detect an off-hook condition (Hangup Box Monitor selected). The following operation 
then occurs when the microphone is taken off-hook:
Conventional Channel Selected - Scanning temporarily halts (if applicable) and the 
Monitor Mode described in Section 5.2 is enabled. However, the receiver unsquelches 
only if a carrier is detected.
SMARTNET/SmartZone/P25 Trunking Channel Selected - Scanning temporarily 
halts if applicable.
If the off-hook condition is not detected (Hangup Box Monitor not selected), the 
microphone hook state has no affect on radio operation.
4.10
Surveillance Mode
If the Surveillance mode is programmed, the backlight, all alert tones, and front panel 
LED indicator can be disabled individually or totally, based on programming.
The transmit/receive LED indicator, display and keypad backlight, and all alert tones can 
be disabled. When setting is enabled, the radio will power up in Surveillance mode with 
the selected options active. A function button can also be assigned which will activate and 
deactivate surveillance mode at the user’s discretion. It overrides any other programming 
of these functions such as a Tone or Backlight option switch.
This feature can be turned ON and OFF by the user via menu selection or by the 
Surveillance Mode option button (if programmed). The user selected mode permanently 
overrides the programmed mode if applicable.
4.11
Public Address
This feature allows a single microphone to be used for either radio or public address. An 
external public address system can be connected to the radio accessory pigtail cable. 
External PA function without a siren controller is provided for cases when the siren 
function is not required. This is a low level output, so some type of PA amplifier is 
required. The Mic To PA option button (or menu selection) controls this feature.