HC3
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User Manual
Rev. 1.0L - 16/05/01
7)
Adjust the variable capacitors (3) and (4), relative to the second amplifier
output, to maximize the power level measured by the coupler’s instrument.
8)
Adjust the variable capacitors (5) and (6), relative to the third amplifier output,
to maximize the power level measured by the coupler’s instrument.
9)
Repeat steps 6, 7 and 8 until the system power reaches its maximum.
10) Reassemble the coupler’s upper cover.
11)
Adjust the system output forward power to the nominal value.
12) If the compensation is done because one amplifier was replaced, it is normally
necessary to operate only on the capacitors related to the substituted amplifier.
8.3
Power Combiner
The Power Combiner circuit mounted on the rear part of the equipment on the left
side, is used to combine the output powers of three amplifiers.
The circuit is realized with suspended-substrate strip lines plus 50Ohm coaxial
cables and guarantee equal phases on the three input power ways that are
combined to obtain the antenna output power.
Three resistive terminations placed on the main cooler serve to absorb any
unbalanced powers in case of faulty or performance differences of some amplifier.
8.4
Remote Card
This Card mounted on the right side of the equipment in rear position, allows to
switch off the Auxiliary Out A.C. Line in case of any faulty of the equipment.
8.5
CPU
This subsystem is composed by three cards: the CPU card, the display card and
the analog section card.
This subsystem implements all the software functions (measurements, protection,
control, data display, communications) described in the previous chapters.
8.6
External telemetry card (optional)
This optional device is designed to interface to the telemetry connector of the HC3
LCD, and its main role is to give to the user a number of dry contacts related to the
status of the amplifier. The contacts can be configured as normally open or closed,
and are triggered by the four user settable thresholds plus LOC/REM, WAIT, FAULT,
ON, OFF, INHIBIT.
The analog signals produced by the hybrid copupler are replicated on a DB9
connector.
