Harris ATLAS ANALOGUE, Руководство пользователя

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7/26/05 888-2523-001 1-7
WARNING: Disconnect primary power prior to servicing.
Section 1 Introduction
ATLAS Analogue
transmitter. It includes an SNMP (Simple Network Management Protocol) manager
which allows integration with most Control Systems via the Internet or LAN.
1.2.4 PA Module
The Atlas Analogue PA Module utilizes LDMOS (laterally diffused metal oxide semi-
conductor) amplifiers to produce up to 1435W peak sync power output. Each module
weighs approximately 23.6kg and can be removed while the transmitter is running. A
single cabinet Atlas Analogue transmitter can have 2, 4, or 8 PA modules to achieve the
various power levels shown in Table 1-1. A block diagram of the PA module is shown
in Figure 1-4.
Each PA module consists of the following components:
a.
PA Module Controller Board - Responsible for all monitoring and protection of
the module. Reports to the transmitter Main Controller via the CAN bus but is
also connected to the parallel control lines in case the CAN bus is not operational.
b.
Phase and Gain Board - Provides for module phase and gain adjustments to mini-
mize module combiner reject power. Also provides for cabinet phasing for the 2
cabinet transmitters to minimize cabinet combiner reject power.
c.
Pre-driver Pallet - Provides enough power to drive the 2 way splitter and the 2
driver pallets.
d.
Two (2) LDMOS Driver Pallets - Provide enough power to drive the 4 way split-
ters and the inputs to the power amplifier pallets.
e.
Pallet Splitter and Combiner - Actually two 4-way splitters and one 8-way com-
biner.
f.
Eight (8) LDMOS Amplifier Pallets - When combined, they provide up to 1435
watts of peak sync power at the output of the module.
g.
Liquid Cooled Cold Plate - Mounted directly to the 8 LDMOS power amplifier
pallets and power supplies for cooling.
h.
RF Output Directional Coupler - Samples both Forward and Reflected power for
metering, module automatic level control (ALC) and module VSWR protection.
i.
Integrated Power Supply.
Each Atlas Analogue PA Module is a self-contained 1435W transmitter including the
power supply with its own internal control, monitoring and protection. The modules
only receive basic On/Off, Mute, Restart, Phase and Gain commands from the
transmitter control system. This means that each module will protect itself without
relying on the system controller.