AR 60S1G6, Руководство по эксплуатации и обслуживанию

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Model 60S1G6
16 Rev C
3.2.2 A3 Driver Amp
The Driver Amp is assembled on thin film substrates. It has two (2) GaN amplifier sections. Each section is
input and output DC isolated by coupling capacitors. A 90
˚
quad coupler combines the RF outputs. 50Ω
termination resistors absorb any difference signals and help to improve the input and output VSWR of the
module. The module has a gain of approximately 10dB and delivers 20 watts of RF power. Active bias
circuitry regulates the DC current through RF devices. The nominal DC current for this amplifier is
approximately 3.2A from a 25.7V supply. Logic low voltage on the fault pin indicates a low or high current
condition exists on GaN FET 1 (bottom) or FET 2 (top).
3.2.3 A5-A8 Output Power Amps
The output power amplifiers are identical in construction and performance to the driver amplifiers described
in 3.2.2.
3.2.4 A4 Four-Way Splitter
The Four-Way splitter is a multi-section, broadband, Wilkinson splitter. The input signal is split into four
equal-amplitude, equal-phase signals. The amplitude of each signal is 6–6.5dB below the input signal when
both outputs are terminated into 50Ω loads.
3.2.5 A9 Four-Way Combiner
The Four-Way T-combiner is impedance-matching. When the outputs of the four quad amplifiers are fed to
the four-way combiner, the combined output will be approximately 6dB above the output of a single quad
amplifier.
3.3 POWER SUPPLY
Power supply PS1 supplies a +5VDC housekeeping supply for the control system assemblies A14
Control/Fault Board and A12 Interface Board.
PS1 also su25.7 VDC at 16.0 amps, +24 VDC at 7 amps, -24 VDC at 2 amps. PS1 is a switching
supply that automatically sets the AC input circuits to the correct connections for the line voltage 90-264
VAC input ranges 47-440 Hz.
The +25.7 VDC at 16.0 amps power supply is fed to the A3 Driver and the A5-A8 quad amps and supplies
the FET drain voltage for these amplifiers. The +24 VDC at 7 amps is for fan B1 and the regulator assembly,
where it is regulated to +15V.
The –24 V at 2 amps power supply is regulated to –12 V and –5 V through the A13 regulator board and is
also regulated to -12V in the A1 pre-amplifier.