Nautel XL12, Технические инструкции

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12 000 WATT AM BROADCAST TRANSMITTER
XL12
Page 1-1
01 January 2002
SECTION 1
GENERAL INFORMATION
INTRODUCTION
1.1
The XL12 AM broadcast transmitter system
is a totally solid state, medium wave, amplitude
modulated, broadcast transmitter system. It may be
operated as a monaural or an AM stereo transmitter.
The exciter stage contains duplicated RF drive
PWBs, interphase PDM driver PWBs, exciter DC
power supplies, RF drive buffer amplifiers and RF
drive DC power supplies, which are connected as an
active and a reserve exciter. The transmitter
contains eight RF power modules and a high current
AC/DC power supply. It operates at one preset
frequency, in the AM broadcast frequency band, into
a nominal 50 ohm, unbalanced, transmission line.
Typically the transmitter will operate continuously at
140 percent positive peak programme modulation at
12 000 watts. Remote control interfacing is a
standard feature.
FACTORY SUPPORT
1.2
Nautel provides after sales factory support.
Technical assistance is available on a 24 hour, seven
days a week basis. A factory service facility for
repair of modules/assemblies is also available. Refer
to the
Factory Support
portion of the
Warranty
pages at the front of this manual for additional
information.
PURPOSE AND SCOPE OF MANUAL
1.3
This
Technical Instruction Manual
provides the information required to install, operate
and maintain the transmitter. Detailed information
for modules/assemblies, which are normally removed
from the transmitter for servicing, is not included.
Service Instruction Manual
appendices provide
information for troubleshooting and maintaining
bench-repairable modules/assemblies used in the
transmitter.
1.3.1 FAMILY TREE:
The family tree for this
transmitter is depicted in figure 8-1. It identifies the
major assemblies and shows their hierarchical
assembly relationship. It also identifies the reference
designation assigned to each assembly and where
their parts list is located.
PURPOSE OF EQUIPMENT
1.4
The XL12 - 12 000 watt AM broadcast
transmitter system is intended to be used in
conventional AM broadcasting stations. Remote
control facilities are incorporated to allow unattended
operation at a transmitter site, remotely located from
station studios.
MECHANICAL DESCRIPTION
1.5
The transmitter's modules/assemblies are
housed in a single rack. Figures MD-1 thru MD-29
provide assembly detail and identify the location of all
electrical parts. The mechanical drawings are
presented in order of the reference designation
assigned to their assemblies. Refer to the list of
mechanical drawings in table 10-1 to locate a
specific illustration.
NOTE
Some modules/assemblies may have an alpha
suffix on their designator (A, B, C, etc.). The
suffix is assigned alphabetically and indicates the
module contains minor component or circuit
variations. Since a change that merits an alpha
suffix change will normally enhance the
operation of the affected module/assembly or
compliment the operation of an external circuit, it
is not recommended that later versions be
interchanged with earlier versions. All earlier
versions can be replaced by later versions.
TECHNICAL SUMMARY
1.6
A Technical Summary is provided at in the
specifications brochure at the front of this manual.
SPECIAL TOOLS AND TEST EQUIPMENT
1.7
Table 1-1 - Test Equipment, lists the test
equipment that is required to operate and maintain
the transmitter. Table 1-2 lists the special tools
required.
GLOSSARY OF TERMS:
1.8
Table 1-3 - Glossary of Terms, provides a
list of all unique terms, abbreviations and acronyms
used in this publication.