Canon PC920 Service Manual page 307

CHAPTER 11 TROUBLESHOOTING
2. Adjusting the Intensity of the Scanning Lamp
Adjust the intensity of the scanning lamp if you have replaced any of the following:
• DC controller PCB
• Composite power supply PCB (See p.11-41.)
• Scanning lamp
Caution:
If you have performed this adjustment, you must always perform AE adjustment.
Making Adjustments
1) Set a cartridge in the machine.
2) Set the density correction switch (SW101) to its middle index.
3) Turn off the AE mechanism, and set the copy density adjusting lever on the control panel to its
middle index.
4) Place the Test Sheet on the copyboard, and make a copy.
5) Turn VR107 on the DC controller PCB gradually until gray scale No. 9 is barely visible.
11-42
Figure 11-263
J130 J114
J107 J103
VR103VR102
Figure 11-264
VR107 and Copy Density
Direction of VR107
Clockwise
Counterclockwise
Table 11-207
COPYRIGHT © 1999 CANON INC.
SW101
VR107
J102
VR104 VR105VR106
VR107
J106
J104
J105
J109
Copy density
Lighter
Darker
CANON PC800s/900s REV.0 AUG. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)