User's Manual

20-523 Owner’s Manual
Page 13
Motorola systems are trunking systems used primarily by business and public safety groups to efficiently
allocate a small number of frequencies (as few as 5) 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 talk group. For example, the east side
patrol officers might all be assigned to talk group 2160. One channel in the system is continuously
transmitting data that identifies which talk groups are active on which channel. In addition, this talk group
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 talk
group ID data included with the transmission. In the open mode, the scanner stops on the transmission and
displays the talk group ID on the bottom line of the display. In the closed mode, the scanner only stops on the
transmission if the talk group ID matches a talk group ID that you have stored in the bank’s talk group ID list
and have not locked out.
Motorola trunking systems come in three categories: Type I, Type II, and Type I/II Hybrid. Each category
displays and uses talk group IDs in slightly different ways.
Motorola Type I IDs are in the form FFF-SS, where:
FFF=Fleet ID
SS=Subfleet ID
Type I systems are usually organized with different user groups assigned to different fleets. For example, a
valid fleet/subfleet ID identifying all detectives within a police department might be 000-12, where 000
identifies all police users and 12 identifies the Detective division.
To properly map the raw Type I data to the correct fleet-subfleet format, you must program the correct fleet
map into the scanner. Fleet map information is widely available on the Internet for most Type I systems in
use.
Type II system talk groups are identified by a 5-digit number. Valid talk group IDs are divisible by 16. If you try
to enter an invalid talk group ID, the scanner rounds the ID down to the next valid ID.
Type I/II hybrid systems use both fleet-subfleet and 5-digit formats for talk group IDs.
Note: If the scanner decodes control channel data while receiving transmissions from a Motorola trunking
system, CNTRL appears on the bottom line of the display.
EDACS Mode
You can set your scanner so it decodes the talk group IDs used with EDACS (GE/Ericsson) trunking
systems. This setting is called the EDACS mode.
EDACS systems are trunking systems used primarily by business or private communications service
providers, as well as by some public safety organizations. EDACS systems transmit active talk group
information only on a dedicated control channel.