E.F. Johnson Company 53SL ES Series, Руководство по эксплуатации

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5-6 53SL ES Series Mobile Radio Operating Manual April 2009
Horn Alert Section 5 - Radio Wide Features
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 ignition 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 ignition switch is turned OFF. At the same time, advantages of ignition switch
control are used such as preventing the battery discharge that may occur if the radio is left
ON for an extended period.
5.8 Horn Alert
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 53SL ES Installation Manual for more information on how to install this feature.
Additional information on the horn alert feature follows:
• It activates when receiving any Unit call in the P25 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 Unit call is received.
5.9 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: