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Installation of Navitar/NuView Series 643 lens on 3M model MP 8790 projector.
TOOLS REQUIRED: PHILLIPS HEAD SCREWDRIVER
Disassembly:
1. Disconnect unit from power source and place projector with lens facing you. Remove
two (2) screws (one on each end) holding front cover of projector. Remove screw
from bottom-center of projector. Remove cover and set aside for reinstallation.
2. Remove four Phillips head screws holding prime lens in place and disconnect the
power cable for the zoom/focus motor and remove prime lens.
Assembly:
1. Ensure that your Navitar/Buhl lens and its adapter are separate. Using four (4)
Phillips head screws removed in (2), above, install the adapter correct side up into
the projector.
2. Replace the front cover of the projector removed in step 1, above.
3. To focus, gently twist the front of lens. To zoom, loosen thumbscrew and twist
knurled ring (zoom lenses only, of course). Re-tighten thumbscrew. CAUTION: Do
not twist entire lens out of adapter!