7-1
SECTION 7
MAINTENANCE AND ADJUSTMENTS
7.1
Digital Soundhead Maintenance
7.2
Print Cleanliness
7.3
Adjustments
7.1
Digital Soundhead Maintenance
The Cat. No.700 Digital Soundhead should be kept clean and free of dust and dirt for best
performance, just like your analog soundhead. Wiping the external surfaces with a clean
cloth on a regular basis will keep the head looking new. The optical path should be
inspected regularly and kept clean with a photographer’s lens cleaning kit (available from
most camera stores). Use care not to scratch the lens. The film path (rollers and drum)
should be cleaned regularly, as you would on the projector. No acetone, carbon
tetrachloride, or other dangerous cleaners should be used.
Replacing the Exciter Lamp
The exciter lamp in your Cat. No.700 Digital Soundhead has been designed for long life
and should provide over 8000 hours of reliable use under normal circumstances.
Routine replacement will depend on your theater’s hours of operation. To replace the
exciter lamp, carefully remove the six screws holding the rear cover/power supply of the
Digital Soundhead. Allow the lamp to cool if necessary. With the rear cover removed,
the lamp will be visible but still attached to the rear cover assembly by its two supply
wires. Slide the lamp out of its base. Carefully remove a new lamp from the protective
box, and using gloves or a clean, lint-free cloth, replace the lamp in the socket. Be careful
not to touch the bulb or inner surface of the reflector in the lamp. If either is accidentally
touched, carefully clean the area with isopropyl alcohol when the bulb is cool. Slide the
lamp back into its base in the soundhead, replace the rear cover assembly and tighten the
six screws.
Replacement lamp:
Use only General Electric EPT
Reflector-type
42W
Dolby Part No. 34010
Figure 7.1 Digital Soundhead Exciter Lamp Replacement
Remove power before
removing circuit boards.
Always use static
precautions.
