Paradise Datacom 4 RU Chassis, Руководство по эксплуатации

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74 201627 REV X 4 RU SSPA Chassis Operations Manual
The schematic of
Figure 6-2
shows the electrical position of the block up converter. It
is powered from a +15 VDC supply available from the Back Plane Board Assembly.
The Block Up Converter is simply cascaded with the SSPA at the input of the amplifier.
Figure 6-3
shows the basic block diagram of the system.
It is important to remember the requirement of a 10 MHz reference oscillator when
operating an SSPA with BUC (SSPB). If the 10 MHz reference is not present, the M&C
will report a BUC alarm and the SSPA module will mute. This ensures that no spurious
or ‘off frequency’ transmission could originate from the amplifier.
Note: Unless the BUC has the built-in internal reference option, with no 10 MHz
reference signal present on the IFL input there will be no output signal from the
SSPA.
Figure 6-3: Block Diagram of Block Up Converter / SSPA System
Figure 6-2: Schematic, Optional Block Up Converter
RF INPUT
TO SSPA
MODULE