AR 10036733, Operating And Service Manual

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Model 30S1G6
3.2.2 A2 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 10-15 watts min. of RF power. Active
bias circuitry regulates the DC current through RF devices.
3.2.3 A4 and A5 Output Power Amps
The output power amp is assembled on thin film substrates. The GaN devices, 90
˚
quad couplers and bias
board are the same as the driver amp. The gain should be about 0.5dB less than the driver amp. It delivers
approximately 15-20 watts of RF power. Active bias circuitry regulates the DC current through RF devices.
3.2.4 A3 and A6 Two-Way Splitter and Two Way Combiner
A3 splits the signal and feeds the input of A4 and A5 quad amps. The output of A4 and A5 are then fed into
A6, the Two-Way Combiner.
3.3 POWER SUPPLY
Power supply PS1 supplies a +5VDC housekeeping supply for the control system assemblies A9
Control/Fault Board and A12 Interface Board.
PS1 also su26.8 VDC at 18.75 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 +26.8 VDC at 18.75 amps power supply is fed to the A2 Driver and the A3 quad amp and supplies the
FET drain voltage for these amplifiers, and is also regulated to +12 V in the preamplifier. The +24 VDC at 7
amps is for fan B1.
The –24 V at 2 amps power supply is regulated to –12 V and –5 V through the A11 regulator board and is
also regulated to -12V in the A1 pre-amplifier.
3.3.1 A4 Regulator Board (Schematic #10031647)
The A4 regulator board filters the +24 VDC and the –24 VDC and has four (4) regulators for the RF
amplifier stages.
U1 is a switched 15VDC regulator. This regulator supplies voltage for the A1 pre-amplifier.
U2 is a +12VDC regulator. This regulator supplies voltage for the A1 pre-amplifier.
U3 is a –12VDC regulator. This regulator supplies voltage for the A1 pre-amplifier.
U4 is a –5VDC regulator. This regulator supplies the gate voltage for stages A1-A3.
16 Rev A