ICOM 288800 Manuale Utente

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DV MODE OPERATION (Optional UT-121 is required for IC-91A)
■ About D-STAR system
In the D-STAR system, repeater linking via a 10 GHz band
backbone and internet network (gateway connection) capa-
bilities are available. This system provides you to with much
wider coverage range during digital voice mode operation.
• D-STAR system outline
For current existing repeater operation, stations that are com-
municating must be in the same repeater’s operating area.
However, in the D-STAR system as in the illustration at left,
the repeaters can be linked via the system repeaters (with a
10 GHz signal). Thus stations A and B can communicate even
though they are in different repeater operating areas.
Also, the D-STAR system repeaters are connectable through
the internet network— gateway connection capability. 
For example, when station B uses the gateway connection
station B can communicate with the station C! 
By using the gateway connection, long distance communica-
tion like DX operation may be possible with 144 or 440 MHz
digital voice!
In the D-STAR system, an independent repeater’s operating
area is called an Area and a group that linking repeaters via a
10 GHz backbone is called a Zone.
Station
A
Station C
 Station D
Repeater A
Repeater D
440 MHz
440 MHz
Repeater C
10 GHz
Station
B
Repeater B
10 GHz
440 MHz
440 MHz
Internet
network
Internet
network
About time-out timer function
The IC-91A/91AD has a time-out timer function for digital
repeater operation. The timer limits a continuous transmis-
sion for approx. 10 min. Warning beeps will sound before
30 sec. (approx.) and just before the timer functioning.