Ricoh A-P4, Service Manual

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1. If you do not have an SMC Report for reference, do SP5990-002 to print the SMC Report
so you can look up and match the SP numbers below with the correct name.
2. Set SP2110 to "0" (for 400 dpi), or to "8" (for 600 dpi).
3. Execute SP2109-08 to reset all the beam pitch data.
4. Do SP2109-001 and enter "144".
• The "144" entry is only a starting point for the adjustment.
5. Do SP2109-003 (400 dpi Initial Setting) if you entered "0" in Step 2.
-or-
Do 2109-004 (600 dpi Initial Setting) if you entered "8" in Step 2.
6. Do SP2902 to print Test Pattern 12.
7. On the test pattern write 144, the value of SP2109-01.
8. Repeat Steps 2 to 7 and change the value of SP2109-001 for every execution (48, 96, 192,
240).
9. Check these test patterns. If the laser beam pitch is not correct, the image looks like a black
vertical stripe pattern (see the diagrams below).
For example, if the pattern made with the value "192" has fewer obvious stripes than the other print-
outs, the correct value is near 192.
10. Do Steps 2 to 7 to adjust the laser beam pitch position until thin lines are of uniform thickness
(no stripes should appear on the printout).
11. In Step 4, input a value estimated to be correct (e.g., if 192 was the closest, try 182), then
do Steps 5 and 6, then if necessary go back to Step 3 and try another value.
After adjusting the laser beam pitch for 400 dpi, adjust it for 600 dpi, using the same procedure as
for 400 dpi (use the SP modes for 600 dpi). Laser beam pitch for 600 dpi should be 24 ~ 48 more
than for 400 dpi.
3. Replacement and Adjustment
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