Ricoh G176, Service Manual

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General
SM 3-1 G176/G177/G176L
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3. REPLACEMENT AND ADJUSTMENT
3.1 GENERAL
3.1.1 PRECAUTIONS ON DISASSEMBLY
ƒ Always turn off the main power switch and unplug the machine before attempting
any of the procedures in this section.
Use extreme caution when removing and replacing components. The cables in the
machine are located very close to moving parts; proper routing is a must.
After components have been removed, any cables that have been displaced during the
procedure must be restored as close as possible to their original positions. Before
removing any component from the machine, note any cable routings that may be affected.
Before servicing the machine:
1. Verify that documents are not stored in memory.
2. Remove the print cartridge before you remove parts.
3. Unplug the power cord.
4. Work on a flat and clean surface.
5. Replace with authorized components only.
6. Do not force plastic material components.
Make sure all components are returned to their original positions.
Laser Unit
1. Do not loosen or adjust the screws securing the LD drive board on the LD unit. Doing
so will throw the LD unit out of adjustment.
2. Do not adjust the variable resistors on the LD unit, as these are permanently adjusted
at the factory. If replacement of the LD drive board is necessary, replace the entire LD
unit.
3. Keep the polygon mirror and toroidal lens free of dust. Laser performance is very
sensitive to dust on these components.
4. Do not touch the shield glass or the surface of the polygon mirror with bare hands.
5. Do not adjust the Laser Synchronization detector on the LD unit, as these are
permanently adjusted at the factory. If the position of the Laser Synchronization
detector has changed from the factory set position, SC 322 will be shown.