Ricoh C211 Service Manual page 123

3. SCANNER SECTION
3.1 OPTICAL ADJUSTMENT
The only change in the optical adjustment procedure is that black level
adjustment should be done first.
The following table shows the reciprocal relationship between adjustment
procedures. When the items listed in the left column are adjusted, the items
listed in the top row must also be adjusted.
Black
Scan
Reading -- ~eduction
Adjustment Items
Level
White Start Focus
(VT2300/
Level 'hading ~:::on Position of
(MTF)
Ratio
VT2500)
Main Scan
(Moire)
Black Level
(VT2300/VT2500)
o 0 0 0
White Level
Shading o 0
Scan Line Posi-
tion
0
0
,0
Reading Start
Position of Main
o 0 0
Scan
Focus (MTF)
,0
Reduction Ratio
(Moire)
o 0
0
0 0 0
The facsimile test chart R-21 (P/N 999921 31) and an oscilloscope are required
for this adjustment.
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