Service manual

TRANSCEIVER PROGRAMMING
4-12
Revised December 2000
Part No. 001-9750-007
With LTR systems, they can also be assigned
arbitrarily. However, for maximum system efficiency,
a scheme should be used which equalizes, as much as
possible, the gaps between numbers. For example, a
five-repeater system should use numbers 1, 5, 9, 13,
and 17. The number assigned to a repeater is
programmed in the repeater, the mobiles assigned to
that home repeater, and the System Management
Module (Multi-Net only).
4.4.2 CHANNEL NUMBER PROGRAMMING
With LTR operation, the mobile transceiver is
programmed with the channel number of each repeater
it can access. With Multi-Net operation, this is not
necessary because the mobile transceiver receives “go
to” channel information over the air. The only chan-
nels that are programmed in Multi-Net systems are the
home and status channels. This allows channels to be
added to the system without reprogramming the
mobiles.
Each Multi-Net system can be programmed with
a different home repeater number if desired. However,
systems with the same site number must be
programmed with the same status channel number.
Refer to Section 4.4.4 for more information on site
numbers.
The channel numbers used to program this trans-
ceiver are listed at the end of this section. The chan-
nels used for programming channels 1-600 are the
same as the FCC channel numbers. However, for
channels above 600, a special programming channel
number is used because some frequencies were
skipped by the FCC scheme. A –12.5 kHz offset can
be specified for channels 1-600 because they have a 25
kHz spacing. This offset does not apply to channels
above 600 because they already have a 12.5 kHz
spacing.
4.4.3 ACCESS PRIORITY PROGRAMMING
(MULTI-NET ONLY)
Each Multi-Net encode (transmit) ID code is
programmed with an access priority number from 1-5.
As stated in Section 5.8.2, this access priority and the
current system priority being transmitted by the
repeater determine if the system can be accessed. If the
priority number being transmitted is greater than the
priority number assigned to the ID code being trans-
mitted, the system cannot be accessed at that time.
There are various schemes that the repeater may use to
determine the current system priority. Refer to the
setup section of the repeater service manual for more
information.
4.4.4 SITE NUMBER PROGRAMMING
(MULTI-NET ONLY)
Each Multi-Net repeater site must be assigned a
number from 1-255. A repeater site is defined as a
group of repeaters which share the same high-speed
data bus (refer to Section 5.6). The site number
programmed in the mobile is used for controlling scan-
ning. A site number is also transmitted in the form of
DTMF tones when a special call is made by a mobile
to a different site. The System Management Module
uses the site information to route the call. Refer to
Section 5.7 for more information on special calls.
If there is only one site that can be accessed by
the mobiles, the site number of the repeater system can
be selected arbitrarily. Each selectable system of the
mobile is then programmed with that site number. If
there are several sites that can be accessed, each site
must be assigned a unique number. Each selectable
system of the mobile is then programmed with the
number of the site that is accessed by that system.
4.4.5 SPECIFYING RIC-EQUIPPED
REPEATERS
When programming the channel numbers of LTR
systems, you can specify if the repeater is equipped
with an E.F. Johnson RIC (repeater interconnect)
controller. If a system with a transmit ID code
programmed for RIC is then selected, the transceiver
will attempt to access only repeaters specified as
equipped with repeater interconnect. This allows both
RIC and non-RIC repeaters to be programmed in each
system.
Without this feature, the transceiver may trunk to
a repeater not equipped with a RIC drawer when a RIC
call is made. No dial tone or other supervision is then
returned when the PTT switch is released which may
be confusing to the user.