Comdel CPS-500AS, Руководство оператора

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8
Typical Specifications
Gain 12 dB (min)
Input power 25 watts (typical)
Output power 550 watts
Input impedance 50 ohms
Output load impedance 25 ohms
Collector voltage (at full output) 33 VDC
Collector current (at full output) 22 ADC
E. Low Pass Filter
The low-pass filter is designed to filter the higher order harmonics and leave a low distortion carrier signal.
This stage also matches the terminating impedance of the amplifier 25 ohms to 50 ohms load impedance. The
filter is a “T” configuration.
F. Directional Coupler
The directional coupler stage produces voltages, which are proportional to the square of both the forward
and reflected power. This stage utilizes inductive (current) and capacitive (voltage) taps to determine the
forward and reflected power. This stage is factory fitted and needs no further adjustment.
VIII. Adjustments and Calibration
The only adjustments required on the CPS-500AS are made to the monitoring and transistor protection circuitry. All
of these adjustments have been performed at the factory and generally will never have to be reset.
A. Over Voltage / Over Current Adjustment
The OV OC potentiometer adjustments are located on the integrated meter assembly FA0637RX. These
adjustments should be altered only when the generator is operating into a 50
Ω
real load. The procedure for
adjustment is as follows:
1. See instructions “Operating into 50
Ω
”
2. Set generator at maximum output power
3. Turn all adjustments to their maximum counter-clockwise limit
4. Set input ac voltage to low line. Then start turning current limit adjustment R21 clockwise until
output power drips to 550W.
5. Set input ac voltage to high line. Then turn the voltage limit adjustment R22 clockwise until
output power just starts to drop. The output power should be 550 watts.
B. VSWR Adjustment
The VSWR set is located in the oscillator module and is adjusted by R1. See FA0401RE. Under high VSWR
conditions, Q6 is biased on and pulls the reference voltage low. When this circuitry is activated, the unit
will go into a pulsed operation until the high VSWR condition is eliminated. The oscillator module is set to
go into limit operation when there is 100W reflected. The procedure for adjustment is as follows.