Repair manual

PARTS REPLACEMENT
4-20
G. REPLACING THE STEPPER MOTOR
Note: Stepper Motor Replacement is to be done at depot facilities only.
1. SPECIAL EQUIPMENT NEEDED:
Digital Palette Gentest Diskette
Host Computer
Video Photometer
Oscilloscope
K42769 Edmonds Scientific 6X Loupe
12979 Final Assembly Alignment Gauge
12991 CRT Collimation Master
12992 CRT Collimator
1-150 Light Source
C-1300 Null Meter
12993 Camera Back Collimator
12988 35mm Collimation Adapter
12996 35mm Fiber Optics Locator Assembly
12995 35mm Adapter Collimation Master
12974 35mm Lens Adjust Wrench
12994 108 Adapter Collimation Master
12974 108 Lens Adjust Wrench
2. REMOVAL: (Figure 4-7)
a. Disconnect AC power from the system.
b. Remove the six screws and washers holding the Cover to the bottom of
the chassis (Figure 4-2). Slide the Cover to the rear and off the chassis.
c. Remove the Light Shield (Figure 4-6).
d. Loosen the CRT clamp screws (Figure 4-6) enough to release the CRT.
Gently pull the CRT back and out of the CRT Mounting Fixture.
e. Remove the four screws holding the CRT Mounting Fixture and remove
the Fixture.
Note: Save and locate the position of the alignment shims located between
the Fixture and the chassis. Shim thickness is color-coded as follows:
Yellow 0.020"
Brown 0.010"
Blue 0.005"