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User Manual
Rev. 1.0 - 05/04/13
PJ3500M-C & PJ5000U-K
The splitter is used to divide input power from PWR Input Measure card and to
supply a part of it to every RF module. The combiner is used to combine output
power from every RF module so as to have total power amplifier.
Splitter, amplifier and combiner are plans so that powers generated from the
amplifiers add its in phase, diminishing the loss of balance and therefore the
dissipation of useful power.
All RF section is placed on a fin that supplies to the cooling through forced
ventilation.
Every RF module supplies 850 watts and is supplied from own switching supply.
The active device used in the amplifier modules is a single LD Mosfet
(MRF6VP11KH).
7.3.2 Wilkinson Splitter and Combiner
Both the splitter and the combiner are made in strip-line technology.
The splitter is used for splitting power arriving from the exciter and supplying one
part to each of the RF modules.
The combiner is then used to combine power output from each module to obtain
the amplifier’s total power.
The two cards ensure equal phases among the powers generated by the RF
modules. One power resistance is used for dissipating the offset power that might
be present in case a module breaks down.
The Splitter card is also fitted with the temperature sensor which is monitored by
the software.
7.3.3 Bias Board
The task of this card is to check and correct the bias voltage of the Mosfets in the
RF amplification section.
This card also supplies the following measurements: current and voltage of each
module, total current and average voltage.
7.3.4 Low-Pass Filter
This filter is located at the back of the equipment.
The task of the low-pass filter is to reduce the harmonic emissions of the amplifier
to below the levels allowed by standards.
