OPERATION
2-8
November 2001
Part No. 001-7240-001
To manually monitor a conventional channel
before transmitting to determine if it is being used by
someone else, proceed as follows:
Using Busy Indicator - With scanning disabled and
the squelch control adjusted as described in Section
2.11.4, note if “
BUSY
” is indicated in the lower part
of the display. If it is, a carrier is being detected on the
currently selected conventional system (channel). If
this indication is not displayed, the channel is not busy
and the message can be transmitted.
Using Monitor Mode - If scanning, pressing the
Monitor option switch (see Section 2.5.1) disables
scanning and enables the monitor mode indicated by
in the display. The monitor mode disables squelch
control features so that all messages are heard. If none
are heard, the channel is free and the message can be
transmitted. Refer to Section 2.11.2 for more informa-
tion on monitoring.
2.3.12 LOCALITIES, SYSTEMS, AND GROUPS
When any call is placed, a locality, system, and
group are selected. Definitions of these terms follow.
Localities
An LTR-Net or LTR locality is typically a single
repeater site in which the repeaters are co-located and
interconnected by a common bus to form a trunked
channel group. A conventional locality may or may
not include repeaters at the same physical site. A
locality can include up to twenty repeaters.
Unique locality parameters include the channel
frequencies and bandwidth of each repeater at the site,
the status repeater (LTR-Net only), and the repeaters
equipped with telephone interconnect (LTR only) and
companding. Up to approximately 25 LTR-Net or 60
LTR/conventional localities can be programmed (the
maximum number decreases as the number of banks,
systems, and groups increases).
Systems
Systems are a collection of groups and other
information unique to that system (see next para-
graph). Each system is linked to one of the
programmed localities, and up to 99 systems can be
programmed. Each system is programmed with a
unique alpha tag and can have a different display
number in each bank (see Section 2.4.1).
LTR-Net and LTR systems are programmed with
the home repeater number, a collection of groups, and
a transmit inhibit block of ID codes (see Section
2.8.4). The home repeater number and group ID code
form the address for group calls. In addition, the home
repeater is monitored for incoming call information
(the status repeater serves as a backup with LTR-Net
operation).
Conventional systems select a specific radio
channel and include one or more groups, each of
which can select unique coded squelch information on
that channel (see following).
Groups
The groups assigned to a system select individual
call information. Up to 99 groups can be assigned to
each system. With all three types of operation, each
group is programmed with a unique alpha tag, group
scan, call indicator, and other information. The avail-
able group types are as follows.
LTR-Net Group Types
Dispatch - Used to place and receive standard group
(mobile-to-mobile) calls. Encode and decode IDs
from 1-239 can be specified.
Telco - Used to place and receive telephone calls.
Auxiliary - Used to place and receive unique ID and
directed group calls.
Data - Currently not available.
LTR Group Types
Dispatch - Used to place and receive standard group
(mobile-to-mobile) calls. Encode and decode IDs
from 1-250 can be specified when accessing an LTR
locality (site). If an LTR-Net locality is being
accessed, IDs from 1-239 can be specified.
Telco - Used to place and receive telephone calls. A
RIC (interconnect) ID is also specified. This code is
one that has been reserved on the repeater system
for telephone calls.
