P R E V E N T I V E MAINTENANCE SERVICES
20. Tools and Materials Required for
The following tools and materials are required for organizational
maintenance of Still Picture Projector AP-5(1):
Signal Corps stock No.
Cleaner, liquid, lens
Screw. driver, -inch
Screw driver, Phillips, PL-469/U
Caution: Do not use emery cloth, sandpaper, crocus cloth, or similar
abrasive to clean the equipment. Use only the cleaning agents specified.
21. Definition of Preventive Maintenance
Preventive maintenance means making systematic checks and adjust-
ments at regular intervals to keep equipment operating at top efficiency.
It is not the same as trouble shooting or repair. The purpose of pre-
ventive maintenance is to prevent breakdowns and the need for repair.
The purpose of trouble shooting and repair is to locate and correct
existing defects. The importance of preventive maintenance cannot be
overemphasized. Failure or inefficient operation of one component of
the equipment may cause the failure of the entire unit. lt is vitally
important, therefore, that operators and repairmen maintain their
22. Preventive Maintenance Techniques
The following table shows preventive maintenance procedures for
Still Picture Projector AP-5 (1) . This list contains information on what
to check, when to check, how to check, and precautions to be taken
before, during, and after checking.