RC4500 Antenna Controller Chapter 4 Software Configuration / Installation
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The polarity of a waveguide is determined by its narrow dimension. In the diagram, position A shows port
1 as being at the 0.0 degree orientation. In position B, port 2 is at the 0.0 degree orientation.
NOTE: before establishing the polarization reference position, the antenna platform must be
leveled so there is no pitch or roll. Any platform pitch and/or roll present in this calibration step
will later cause inaccuracy in automatic polarization movements.
Using an accurate inclinometer or level, position the polarization axis so that the waveguides align with the
local vertical and horizontal. Typically this position will also be close to the center or travel of the
polarization potentiometer or resolver. If not, adjust the polarization potentiometer or resolver to achieve
this value.
For antennas implementing a potentiometer for polarization position feedback, a reference voltage from
the potentiometer needs to be set while the feed is in the center of travel (aligned with the local vertical /
horizontal.)
4.2.3.3.1 Polarization Reference Voltage for Potentiometer
The voltage can be read from the MAINTENANCE – VOLTS – 12 BIT ADC VOLTAGES screen.
AZ: 0.0012 1 31659 12 BIT ADC
EL: 0.0012 1 32264 L1:0
POL: 2.5000 2048 14939 L2:1
SIG: 3.3346 2731 L3:1
Enter the voltage into the VREF configuration field in the CONFIG – POLARIZATION CALIBRATION
screen.
VREF:2.500 OFF: 0.000 CONFIG-POL
CCW:-100.000 CW: 100.000 SF: 40.000
ZERO DEG VOLTAGE <1.000–4.000 VOLTS>
To verify that the data has been entered correctly, return to the MANUAL mode screen. The displayed
polarization angle in MANUAL mode should be 0.0 +/- 0.1 degrees.
AZ: 185.93 RF: 50 MANUAL
EL: 29.61 SAT:
PL: 0.00 SPD:FAST UTC
<MODE>MENU <0-9>JOG ANTENNA 14:25:47
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