Konica Minolta bizhub PRO 920 Service Manual page 413

Field Service Ver2.0 Aug.2005
*6 Blade auto switching timing
Set the auto switch timing of the cleaning blade.
*7 Regular toner supply amount
When the original with less coverage (1% or less) is
printed for a long period of time, the toner density of
developer gets increased, causing the image back
ground to occur. Changing this switch to "1" reduces
the toner amount periodically supplied to prevent the
image back ground.
Note
• Changing this switch to 1 in the original hav-
ing a typical blacking ratio results in the
image getting thinner.
*8 Image density selection (laser PWM) for copier
Change the image writing laser PWM to make image
lighter.
Note
• There are two kinds of DIPSWs to lighten
image density: laser PWM (5-2/3) and toner
control patch density (27-2/3). As a priority of
adjustment, adjust in the following order.
1) Laser PWM
2) Toner control patch density: approx. 0.5%
down
Using this setting alone may cause white
spot on the solid section. Be sure to use
together with DIPSW23-2/3/4 (toner den-
sity of developer) approx. 0.25% up or
0.5% up.
*9 Background density adjustment (photo mode)
Change the laser PWM and set the image density for
the highlight section while in the photo mode.
The numerical values given in the table represent the
density in the image density range of 0 (white) to 255
(black).
Mode
Every 150,000 prints
Every 250,000 prints
Every 300,000 prints
Every 400,000 prints
Mode
Equivalent to 2% of coverage
Equivalent to 0.4% of coverage
Mode
Standard (*190/170)
Lighter (*1167/137)
Lightest (*142/112)
Standard (*190/170)
* 0 (white) to 255 (black) represent density within
the image density range. Numbers represent
each image density at the line speed 460 mm/s,
290 mm/s from left.
Mode
PWM 16
PWM 0
PWM 8
PWM 24
10. TECH. REP. MODE
2-7 2-6
0 0
0 1
1 0
1 1
3-0
0
1
5-3 5-2
0 0
0 1
1 0
1 1
6-1 6-0
0 0
0 1
1 0
1 1
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