E F Johnson Company 2425341 Benutzerhandbuch

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programming “Forever” so there is no automatic 
power off. 

Both the ignition switch and the power switch 

must then be on for radio power to turn on. The delay 
can be overridden at any time by turning power off 
using the front panel power switch or turning the igni-
tion switch back on.

This turn-off delay can allow calls to be received 

or the horn alert to be active for a time after the igni-
tion switch is turned off. At the same time, advantages 
of ignition switch control are utilized such as 
preventing the battery discharge that may occur if the 
radio is left on for an extended period (see 
Section 7.5). 

The horn alert feature* sounds an external alert 

such as the vehicle horn when certain calls are 
received. It is available if a Horn option switch is 
programmed and the proper connection has been made 
to the external alert. The horn alert output is pin 4 of 
the accessory cable, and an external driver circuit of 
some type is usually required. Refer to the Installation 
section of the 5300 Service Manual for more informa-
tion on how to install this feature. 

Additional information on the horn alert feature 

follows:

•

It activates when receiving any Unit call in the 
conventional mode and any Private/Unit and Call 
Alert (paging) call in the SMARTNET/SmartZone 
and P25 Trunked modes. It does not sound when 
receiving standard Group or telephone calls, and is 
not programmable on a per call basis.

•

It must be manually enabled and disabled by the 
Horn option switch. It is not controlled by the 
vehicle ignition switch. When it is enabled, “HORN 
ON” is briefly displayed, and when it is disabled, 
“HORN OFF” is briefly displayed. It defaults to the 
off mode whenever power is turned on. 

•

If a power turn-off delay is programmed as just 
described, it is functional during that delay. 

•

When activated, it can be programmed to sound for 
three 1-second beeps or continuously for 2-90 
seconds. It then turns off until another call is 
received. 

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 micro-
phone is taken off-hook:

Conventional Channel Selected - Scanning tempo-
rarily halts (if applicable) and the Monitor Mode 
described in Section 5.3 is enabled. However, the 
receiver unsquelches only if a carrier is detected. 

SMARTNET/SmartZone/P25 Trunked 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.

If the Surveillance mode** is programmed, the 

backlight, all alert tones, and front panel LED indi-
cator are totally disabled in all operating modes.

This feature can be turned on and off by the user 

if the SURVLC option switch is programmed. The 
user selected mode permanently overrides the 
programmed mode if applicable. (This feature is avail-
able only with firmware 1.22/2.0/3.0 or later and 
PCConfigure 1.20 or later.)

An external public address system can be 

connected to pin 7 of the radio accessory pigtail cable. 
This is a low level output, so some sort of PA amplifier 
is required. The External PA option switch is required 
to control this feature. 

In the public address mode, microphone audio is 

always routed to the PA system, and the radio can be 
programmed so that receive audio is also routed. 

** This feature requires 5300 operating (ARM) soft-
ware 1.16 or later (or 2.0/3.0 or later).

* This feature requires 5300 operating (ARM) software 
1.19 or later (or 2.0/3.0 or later).