Andrew 174100, Installation And Maintenance Manual

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2) To remove the polarizer motor, polarizer vane settings must first be measured when the polarizer is in
the circular polarized state. To do this, loosen the setscrew on the motor side of the cam shaft
coupling while holding the vane plate (Figure 4-2) in place.
3)
Press the vane plate down and rotate the cam shaft so the highest part of the cam holds the vane plate
in the circular polarized position.
4)
Measure dimension >A= of Figure 4-2.
5) Rotate the cam shaft until the vane plate bottoms out on the linear adjust stops.
6) Remove the two nuts mounting the motor to the frame, disconnect leads and remove the motor.
7) Replace the motor in the reverse order.
8) With the setscrew loose on the cam shaft coupling, repeat step 3.
9) Loosen the motor mounting screws and adjust the motor position until dimension >A= is the same as
measured in step 4).
10) Rotate the cam shaft until the setscrew can be tightened against the flat on the motor shaft.
11) Operate the polarizer several times to ensure proper operation.
Capacitor and Diode removal and replacement:
1) Capacitor and Diode Replacement Kit 174763 contains Qty.1 capacitor Cl, Qty.1 capacitor C2, Qty.2
diodes, Qty.2 terminal rings and insulation sleeving necessary to carry out the replacement.
Either capacitor may be replaced as follows:
2 )
Un-solder and discard the old capacitor.
3 ) Cut two lengths of insulation sleeving just long enough to cover the wire leads at both ends of the
capacitor. With the sleeving on the wire leads, wrap the leads around the appropriate terminals up to two
turns then soft solder per ANSI standard IPC -A-610A.
Either diode may he replaced as follows:
4 )
One end of each diode is crimped to a terminal ring which is fastened to the terminal strip. Remove
both diodes from the terminal strip and un-solder and discard the old diodes. NOTE: Before