Radio Shack PRO-96 Scanner User Manual


 
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agencies to efficiently allocate a
small number of frequencies (as
few as three) to many groups of
users (as many as several
thousand). To do this, each group
of users in the system is assigned
to a specific talkgroup. For
example, a city’s east side patrol
officers might all be assigned to
talkgroup 2160. One channel in
the system is continuously
transmitting data that identifies
which talkgroups are active on
which channel. In addition, this
talkgroup information is also
transmitted as subaudible data on
each active channel.
When the scanner receives a
transmission on a channel set to
the Motorola mode, it first decodes
the talkgroup ID data included with
the transmission. In the Open
Mode, the scanner stops on the
transmission and displays the
talkgroup ID on the bottom line of
the display. In the Closed Mode,
the scanner only stops on the
transmission if the talkgroup ID
matches a talkgroup ID that you
have stored in the bank's
talkgroup ID list and have not
locked out.
Trunking systems covered by the
Motorola mode come in four
categories: Type I, Type II, Type I/
II Hybrid and APCO-25. Each
category displays and uses
talkgroup IDs in slightly different
ways.
Motorola Type I IDs are in the form
FFF-SS, where;
FFF=Fleet ID