R.V.R. Elettronica HC2 LCD, Руководство пользователя

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HC2
26 / 30 User Manual Rev. 1.1L - 07/07/03
8.2 Modules description
8.2.1 Power supply
The power supply of the HC2 uses a mains transformer (70 VA) with selectable
voltage primary circuit (110-120-230-240V) and two secondary windings. The first
is a 3A 0-16V used to supply the remote card, the second is a 2A 11.5V that gives
power to the CPU section.
The CPU section and the remote card have built-in bridge rectifiers and voltage
regulators.
The mains transformer has also the function of a autotransformer for the supply at
115V of the fans.
The CPU section can also be supplied with external 24V dc; this power source is
automatically selected by it if the main voltage is missing for any reason.
8.2.2 Splitter Section
The role of the RF splitter is to divide the RF signal provided by the exciter and to
pass it to the couple of amplifiers.
The circuit is based on a Wilkinson-type scheme and is designed with strip-lines
and coaxial cables. It includes the circuits to adjust the phases of the output feeding
the external amplifiers, to maximize the overall output power and to minimize the
rejected power.
The splitter includes a resistive termination that dissipates possible unbalancement
power due to faults or different performances of the amplifiers.
8.2.3 Coupler section
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 coupler section includes resistive terminations mounted on the heat sink that
dissipate possible unbalancement power due to non-optimal adjustment, different
performances of the amplifiers, or any malfunctioning in the transmitter.
8.2.4 Remote Board
This board is installed on the right side of the device. It is controlled by the CPU,
and its function is to cut the power in the auxiliary mains plug in case of alarms.