Motorola GM300 Series Selling Manual page 55

Additional Decode Functions
TX Cycle: Telegram
A special 5 tone emergency telegram can be transmitted, to activate emergency mode on the
central dispatcher's equipment (e.g. Centro Plus desktop controller). This telegram can also contain
Status information.
TX Cycle: Voice Message
An emergency message can be pre-recorded which is sent automatically when the emergency call
feature is activated. This message can contain, for example, the user's location or status which
would be useful to the recipient, especially if the user is unable to talk.
Refer to Voice Storage to use this feature.
13.6.2 On/Off Switch Enable
The On/Off switch can be programmed to be operational or non-operational when in Emergency
mode. If the On/Off switch is enabled, then when in standard emergency, it is possible to turn the
radio off (and therefore reset the emergency mode). If the On/Off switch is disabled, it is not possible
to turn the radio off. See Power Off Logic section.
13.6.3 Secret Emergency
The radio can be set to "Secret Emergency" . The display and LEDs turn off, the alert tones and side
tones are not generated and the audio is muted; the radio appears to be turned off, even though it is
in fact transmitting and receiving.
In "Standard Emergency" the display, LEDs and alert tones function as in normal radio operation
and they change if the radio changes channel or transmits as part of the emergency operation.
13.6.4 Emergency Squelch
The Emergency Squelch can be set different from the standard squelch setting.
13.6.5 Emergency Debounce
In order that the emergency mode of operation is not entered into by accident, it is possible to
programme the period of time that the emergency button must remain pressed, before the radio
enters emergency mode.
13.6.6 Emergency Revert Channel
A default emergency channel can be specified, so that the radio changes to this channel during the
emergency transmission and reception.
13.6.7 Emergency Microphone Source
The microphone source during TX periods is dealer programmable. It can be either the standard
microphone (which will work even if the PTT is not pressed), or an external microphone wired into
the 16 pin accessory connector. This external microphone can be hidden within the vehicle to avoid
the possibility of an attacker being able to disconnect the working microphone (even if the standard
microphone is ripped out, the radio can still transmit because it is using the hidden microphone).
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