Filter
Top Products
The computer then assigns that talk group to a
specific voice channel and transmits that data over the
control channel. All radios in that talk group switch
over to the assigned voice channel and the user can
begin speaking.
This all typically takes place in about a second...
the person transmitting hears a beep from their
radio when the channel is assigned and then it is OK
to start talking.
the radios send the radio ID, the
fleet and subfleet talk group ID to the control channel
each time they transmit. To program a Type I system,
you need to know the system’s fleet map. The most
common fleet maps are included in “Preset Fleet
Maps” on Page 123. You can also find fleet map
resources on the web.
the radios only send the radio ID
and radio channel code to the control channel. The
central computer keeps a database of radio ID’s and
which talk group is assigned to which channel code
for each radio, so with this system the user’s radio
sends only about 1 /3 the data as a Type I system with
each transmission. Type II systems do not use Fleet-
subfleet talk groups; instead they use a 5-digit ID for
each talk group.
these systems support a mix of
both Type I and Type II users. Like Type I systems,
you must know the system’s fleet map to ensure
proper tracking.
these radios are
similar to Type II systems, but send only the radio ID
and radio channel code to the control channel, trans-
mitting voice in digital form.
The systems in use are:
Motorola Type I –
Motorola Type II –
Type IIi Hybrid —
Motorola ASTRO 25 (APCO 25) –
Understanding Scanning
23