11
4.3 ELEVATION POSITION FEEDBACK
The elevation position feedback is produced by an electronic inclinometer located in the feed box. (See fig below)
No adjustment or maintenance is required. The inclinometer is electronically zeroed in the controller. See Section
2.3 in the controller Manual.
4.4 ELEVATION STOW AND LIMIT SWITCHES
The elevation stow switch is mounted in the Pol cover. The limit
switches are mounted in the elevation actuator gearbox.
The elevation up and stow switch do not require adjustment.
SECTION 5-
FEED AND POLARIZATION POSITIONING SYSTEM
5.1 GENERAL
The Feed assembly consists of feed boom, upper and lower feed brackets, feed housing, RF components and
polarization drive housing. The feed boom is pivoted about the elevation axis to eliminate additional flex-guide
required if pivoted at edge of reflector. The pivot connection at the end of the feed arms in the upper feed bracket
is with brass bushings. A piece of 18” flex waveguide is used at the end of the waveguide tube to the OMT. The
feed/OMT is rotated by chain drive assembly and 12 VDC motor. Position feedback is from a 10 turn potentiom-
eter.
5.2 FEED
The feed assembly consists of an inclinometer, feed horn and OMT with male pivot bushings. The male bushings
pivot in delrin female bushings at each end of the OMT. The Bushings are mounted to a mounting plate. The pol
drive sprocket attaches to the OMT and the waveguide attaches to the other end with M6 screws at the rear
flange of the OMT. The feed/polarization drive is mounted underneath the pol mounting plate in the feed box with
the gear on the outside and the driving pol sprocket to rotate feed.
5.3 POLARIZATION DRIVE
The feed/polarization drive is mounted underneath the pol mounting plate in the pol drive box with a drive
sprocket mating to the motor shaft, which extends through the feed drive box. The polarization drive motor (See
fig on page 11) is a 12 VDC gear motor. Small gear is attached to the end of motor shaft which drives the small
gear to drive the position potentiometer. The controller travel limits are +/- 90 degrees for a 2-port. (See RCI
3050 Controller Manual section 3.3).
