Harris Atlas DVL1100, Техническое руководство

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2/25/03 888-2473-001 4-21
WARNING: Disconnect primary power prior to servicing.
Section 4 Theory of Operation
ATLAS Series™
one side of all the pallets and adjust the bias for the desired idle current on the other
half of each pallet. Then it will store these settings and repeat the procedure for the
other half of the pallets.
If during the bias procedure, one or more of the pallet currents does not fall within
the acceptable margin of error, the procedure will be aborted and a warning of
"Auto Bias Failure" will be sent to the Main Controller and the Fault Log.
For information about running the Auto Bias procedure refer to "5.3 PA Module
Auto Bias Procedure" on page 5-4.
4.4.4.5 Pallet Splitters and Combiner
The two 4-way drive splitters and the 8-way pallet combiner are stripline hybrid
circuits. The pallet combiner also has a directional coupler to sense forward and
reflected power at the output of the module. The forward power sample is used for
power monitoring and module ALC (Automatic Level Control). The reflected
sample is used to protect the module from excessive VSWR.
4.4.4.6 DC Distribution Board
The DC Distribution board is basically a +32Vdc MOSFET switch used to connect
and disconnect the dc power supplies from the pallets. In addition to the dc
switching it also has current and voltage sensing for all PA pallets, drivers,
predriver and the phase and gain board which are used by the Module Controller for
metering, fault protection (over-current, over and under-voltage) and automatic
pallet biasing.
4.4.4.7 Module Controller
The Module Controller uses the 376 micro module and is responsible for the
following:
•
Communicating with the Main Controller via the CAN bus.
•
Moni32V current to each of eight RF pallets, driver, pre-driver and phase
and gain board in the module for over-current conditions and for pallet biasing.
•
Monitoring the heatsink temperature at the pre-driver, and DC Distribution board
temperature.
•
Supply voltage monitoring, with over and under voltage alarms.
•
Executing phase and gain set commands from the Main Controller by generating
I and Q control signals for the Phase and Gain Board.