• TMO group address to DMO group address.
• DMO individual address to TMO group address.
• TMO individual address to DMO individual address.
2.4.4
Gateway and Repeater Synchronization
To communicate using gateways or repeaters, the radio requires synchronization with a gateway or a
repeater.
A gateway or a repeater sends presence signals to radios. If a radio receives presence signals, it stays
synchronized with the gateway or the repeater which sends the signals. If a radio fails to receive a
presence signal it does not immediately lose synchronization. The radio waits for another successful
presence for a time defined by your service provider. This function ensures that communications are
not dropped due to temporary reception issues.
If a gateway or a repeater is unavailable or the radio is not synchronized with a gateway or a repeater,
depending on the setup configured by your service provider, the following scenarios apply:
• The radio falls back to Direct Mode Operation (DMO).
• No direct DMO communications are permitted.
2.5
Graceful Service Degradation Mode
NOTE:
This feature is only available when enabled by your service provider.
The Graceful Service Degradation Mode (GSDM) provides best effort services when the radio enters
a weak signal situation. It provides limited services to users where data circuit operation is no longer
available in radio traffic mode.
The following services are available in GSDM:
• Call-Out message
• Short Data Service (SDS)
• Status message
2.6
Emergency Operations
Emergency Operations are used in critical situations.
The Man Down alert activates the Emergency Alarm service, depending on the service provider
setting.
2.6.1
Emergency Alarm
The emergency alarm is a special status message sent to the infrastructure while starting the
Emergency Operations. The pager may wait for infrastructure acknowledgment for this alarm and
attempts retries.
Each time the pager enters the Emergency Operation, it sends an emergency alarm. When an
emergency alarm is sent successfully, the respective audible tone sounds.
The message can be dispatched both in Trunked Mode Operation (TMO) and Direct Mode Operation
(DMO).
MN003465A01-AF
Chapter 2 : Services and Features
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