Radio Shack PRO-2051 - Manual (Page 64)

64
Beyond the Basics
exact fl eet-subfl eet hierarchy for a particular area is referred
to as fl eet map programming, which is discussed further in
this manual.
The disadvantage of a Type I system is that when PTT is
pressed, the brief burst of data must contain the radio’s ID
and its fl eet and subfl eet. This is three times the amount of
data a Type II radio sends, and as a result Type I systems
usually accommodate fewer users than Type II systems.
Even though there are many Type II systems, Type I systems
are still in use. There are also Hybrid systems which are a
combination of both Type I and Type II. Your scanner defaults
to monitor Type II systems, but it is possible to select a
preprogrammed fl eet map or create a custom fl eet map for
your area. For VHF and UHF Type II trunking systems, you
will need to know the base, spacing frequencies and offset
channels. See “Setting the Base, Spacing Frequencies and
Offset Channel for Motorola VHF/UHF Trunked Systems” for
details.
fl eet map programming
If you have programmed a trunk tracking bank for Motorola,
press TRUNK to start multi-track, and you will see user IDs
on the display. Since the scanner defaults to Type II systems,
all the IDs will appear as numbers; however, if you notice a
mix of odd and even user IDs, for example 6477, 2560, 6481,
6144, 1167, etc., then you are probably monitoring either a
Type I or a Hybrid system.
You may also notice that you are missing responses when
you hold on an active ID. Unlike Type II, Type I/Hybrid
systems require a fl eet map that sets specifi c fl eet-subfl eet
parameters. It is easy to select a fl eet map for your scanner;
what is not always easy is selecting or programming a map
that matches your particular area.