HC3
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User Manual
Rev. 1.0L - 16/05/01
9. Electrical Description
HC3 is composed of different modules wired between them with connectors,
allowing for easy servicing or module substitution.
RF Splitter
RF Combiner
CPU
Display, Keys
..
RF input
from exciter
Telemetry,
RS232,
IIC
Interlock ...
RF input
from Amp 1
RF input
from Amp 3
RF output
to Amp 1
RF output
to Amp 3
RF output
to antenna
This chapter gives the information to indentify, and about the function, of the single
modules.
9.1
Power supply
This equipment has only a transformer (32VA) with a primary 0-100-120-220-240V
and a secondary 16-0-16V, 1A to supply Alarms and CPU Card and the Remote
Card.
9.2
Power Splitter
The Power Splitter circuit mounted on the rear part of the equipment on the right
side, is used to splitt exciter's driving power to three amplifiers.
The circuit is realized with strip plus coaxial cables and three specific circuits can
adjust (equalize) phases on the three outputs that are used to drive the amplifiers.
Three resistive termination placed near to the output serves to absorb any
unbalanced powers in case of faulty or performance differences of some amplifier
to prevent excessive power driving on the well functioning (well loaded) outputs.
The hybrid coupler is factory-adjusted so that the transmitter it is included in will
work satisfyingly works over the whole FM band.
Cases may happen, that it is necessary to perform the RF adjustment of the HC5,
for example if the RF interconnection cables with the amplifiers have been sustituted
with other of slightly different characteristics or length, or if it is desirable to optimize
the transmitter’s performances on a certain frequency.
WARNING: we suggest not to perform the operations described in this chapter
to personnel lacking proper instrumentation and deep knowledge of the
device and its working principles.
