EFJohnson 3000 SERIES - Manual (Page 13)

1-1
INTRODUCTION
SECTION 1 INTRODUCTION
1.1 SCOPE OF MANUAL
This manual describes the 3000 Series Switch
modules and the alignment instructions for these
modules. This manual is not intended to explain the
entire Multi-Net
®
system, just the 3000-Series Switch
segment. For parts list, schematic diagrams, and
circuit board component layout information, refer to
the 3000 Series Switch Service Manual, Part No. 001-
3139-102. For more detailed information on the opera-
tion of the entire system, refer to Multi-Net Applica-
tion Note, Part No. 009-3039-004CD.
1.2 DEFINITIONS
The following are brief definitions of terms and
their usage as they are applied to the Switch.
1.2.1 TRUNKED SYSTEM
Refers to systems which pool multiple channels
and use automatic switching so that all system users
can access any repeater channel that is not in use. This
results in minimum waiting to make a call.
1.2.2 LTR TRUNKED SYSTEM
The LTR
®
(Logic Trunked Radio) systems utilize
a concept called trunking. Trunking makes all repeater
channels on a system automatically available to the
users. This is done by logic control system that contin-
ually monitors the system and updates the mobiles and
repeaters using data messages. These data messages
tell the mobiles which repeater channels are free and
can be accessed if a call is to be made.
1.2.3 MULTI-NET TRUNKED SYSTEM
A trunking system similar to the LTR Trunked
System, but which offers a number of additional and
enhanced features.
1.2.4 CONVENTIONAL SYSTEM
Refers to systems which are licensed on a single
repeater channel. Operation is similar to that of a
community repeater because there is no automatic
access to several repeater channels.
1.2.5 3000 SERIES SWITCH
The Switch connects several forms of communi-
cation together in a “Network” that allows communi-
cation between users in the system.
1.2.6 CALL PROCESSOR
The Call Processor controls the databases for the
Switch and provides processing for certain types of
calls within the system.
1.2.7 SYSTEM AND SUBSCRIBER MANAGER
The Switch along with the System and Subscriber
Manager control the Multi-Net System. The System
and Subscriber Manager is an IBM
®
PC or compatible
computer that is running the Johnson management
program. The System and Subscriber Manager is used
by the System Manager to program, control and
continuously monitor Switch operation. Refer to
System and Subscriber Manager Operating Manual,
Part No. 002-3139-078CD for more information.
1.2.8 REPEATER SITE
A location where one or more repeaters are
housed. Trunked system repeaters are connected to the
same high-speed data bus and are required to be
located close together.
1.2.9 HOME REPEATER CHANNEL
All mobiles have one site repeater channel
assigned as their “Home” repeater. The Home
repeater and Group ID information identifies mobiles
for standard dispatch calls.