Harris ATLAS ANALOGUE, Руководство пользователя

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4-20 888-2523-001 7/26/05
WARNING: Disconnect primary power prior to servicing.
Section 4 Theory of Operation
ATLAS Analogue
4.4.5 PA Module
The Atlas Analogue PA Module is a wideband, high gain, liquid cooled RF amplifier.
Each PA module has a maximum RF output of 1435W peak sync power with a liquid
cooled heatsink. The number of PA modules is determined by the transmitter power
level or model and is given in Table 4-1. A fully populated cabinet has 8 PA Modules.
Each PA module has a smart controller which interfaces via the CAN and parallel
control bus to the transmitter Main Controller. Any faults in the module will be reported
to the Main Controller for diagnostics via the CAN bus. A simplified block diagram of
the PA module is shown in Figure 4-4.
Figure 4-4 PA Module Simplified Block Diagram
The PA Module is made up of the following components:
a.
Phase and Gain Board
b.
Predriver pallet (actually 1/2 of an amplifier pallet)
c.
Two driver pallets
AB
PHASE
&
GAIN
CONTROL
BOARD
Front
End
AB
AB
AB
AB
AB
AB
A
FWD
TEMP
Pin
+250V
3Ø AC
BIAS
RF IN
TO MAIN CONTROLLER
SWITCHED
+28V
ON/OFF
MODULE ENABLE/DISABLE
PA PS
MON
PA PS
MON
RF
OUT
AB
AB
AB
Auto Biasing
Pre-driver
Driver A
Driver B
PA
Power Supply
Pallets
P
a
ll
e
t C
o
m
b
in
e
r
S
p
litte
r
S
p
litt
er
BIAS
BIAS
RFL
CAN Bus