ANTENNA PEDESTAL LEVELING PROCEDURES

CE- 1008

(1) Loosen the pedestal-to-riser base mounting bolts (four required).

(2) Observe the position of the bubble in one of the level bubbles located on top of the antenna mast mounting

flange on the elevation drive support assembly.

(3)

Rotate the antenna mast mounting plate 180 degrees in azimuth and again observe the position of the

bubble.

(4)

Adjust one pair of opposing leveling screws to take out half of the error observed between steps (2) and

(3).

(5)

Rotate the antenna mast mounting plate 180 degrees in azimuth and repeat step (4).

(6)

Repeat step (4) until the level bubble indicates that the pedestal is level at these two positions.

(7)

Observe the position of the bubble in the second level bubble.

(8)

Repeat steps (3) through (6) for the second level.

(9) When the second level bubble indicates that the pedestal is level at these two positions, observe the first

level bubble. Minor adjustments of the leveling screws for each level bubble may be necessary to assure that the

pedestal is level at any position on the azimuth axis.

(10)

When leveling is complete, tighten the pedestal-to-riser base bolts loosened in step (1).

(11) Pedestal Alignment - The servoamplifier has two potentiometers found by removing amplifier cover. After

entire system is aligned, set these two potentiometers (tach feedback and servo gain) at mid-range and turn on servo

drive. Then proceed as follows:

a. Push antenna off null and observe as it returns to null.

b. Increase servo gain until antenna hunts, then reduce gain until antenna returns to null without

excessive hunting.

c. If antenna responds sluggishly, increase gain and stop hunting by increasing tach feedback.

d. If when handwheel control is moved smoothly, antenna follows raggedly, reduce tach feedback and

servo gain to stop hunting.

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