R.V.R. Elettronica HC4, Руководство пользователя

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HC4
27 / 34 User Manual Rev. 1.0L - 01/04/02
9. Theory of Operation
The figure shows the block diagrams of HC4. The blocks are described in the
following chapter:
9.1 Power supply
This equipment has only a transformer with different outputs. The used outputs
are: 0-18V for the supply of the remote card and 0-11,5V for the CPU section. The
rectifiers and the stabilizers are in the two cited cards.
9.2 Power Splitter
The Power Splitter circuit mounted on the rear part of the equipment where are
find the input connector from the exciter and the RF outputs to the amplifiers.
The circuit is realized with strip plus coaxial cables and five specific circuits can
adjust (equalize) phases on the our outputs that are used to drive the amplifiers.
Four 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.
9.3 Power Combiner
The function of the coupler section is to add the RF power portions provided by
the amplifiers and to pass it through the antenna output.
The circuit is based on a Wilkinson-type scheme and is designed with strip-lines
and 50 Ohm coaxial cables. The circuit is comprises between a heat-sink and a
metallic shield, so that the strip line normally aren’t visible.