Uniden UBCD996T - Manual (Page 26)

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. Then it is OK to start talking.
The systems in use are:
Motorola Type I — 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 . The most common fleet maps are included in
the Reference section in this manual. You can also find fleet map resources on the
web such as at .
— 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 / 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, transmitting
voice in digital form.
EDACS trunking works in much the same way as Motorola trunking with a couple of
major differences. In an EDACS system, each frequency used by the system is
assigned a Logical Channel Number (LCN) so that less data needs to be transmitted
by the control channel. Talk groups are assigned in an Agency-Fleet-Subfleet (AFS)
hierarchy.There is one variation of EDACS called SCAT that your UBCD996T can
monitor.
Logical Channel Numbers — each frequency used by the system is assigned an
LCN. This information is programmed into each user radio. When a user presses
PTT, their radio sends their AFS information to the control channel. The computer
then assigns that talk group to a channel and sends the LCN so that all other radios
in that talk group will switch to the correct channel. To program an EDACS system in
your scanner, you will need to know both the frequencies used by the system and
the LCN for each frequency.
— talk group ID’s for EDACS systems are assigned in a
way that makes it easy to see at a glance the affiliation of the user. Each radio is
assigned a 2-digit agency identifier from 00 — 15. For example, 01 might be used by
the police, 02 by the ambulance service, 03 by the fire department, and so on. Each
fleet map
http://www.radioreference.com
Motorola Type II
Type IIi Hybrid
Motorola ASTRO 25 (APCO 25)
Agency-Fleet-Subfleet
1 3
EDACS Trunking
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