Copy Density Adjustment; Copy Density Adjustment Timing; Note For Copy Density Adjustment; Necessary Tool For Copy Density Adjustment - Sharp AL-2021 Service Manual

2. Copy density adjustment

A. Copy density adjustment timing
The copy density adjustment must be performed in the following
cases:
• When maintenance is performed.
• When the developing bias/grid bias voltage is adjusted.
• When the optical section is cleaned.
• When a part in the optical section is replaced.
• When the optical section is disassembled.
• When the OPC drum is replaced.
• When the main control PWB is replaced.
• When the EEPROM on the main control PWB is replaced.
• When the memory trouble (U2) occurs.
B. Note for copy density adjustment
1) Arrangement before execution of the copy density adjustment
• Clean the optical section.
• Clean or replace the charger wire.
• Check that the voltage at the high voltage section and the devel-
oping bias voltage are in the specified range.
C. Necessary tool for copy density adjustment
• One of the following test charts:
UKOG-0162FCZZ, UKOG-0089CSZZ, KODAK GRAY SCALE
• B4 (14" x 8 1/2") white paper
• The user program AE setting should be "3."
1 2 3 4 5
Test chart comparison table
UKOG-
0162FCZZ
1 2 3 4
DENSITY
No.
UKOG-
0089CSZZ
0.1 0.2
DENSITY
No.
KODAK
GRAY 1 2
SCALE
D. Features of copy density adjustment
For the copy density adjustment, the image data shift function pro-
vided in the image process LSI is used.
List of the adjustment modes
Auto mode Brightness 1 step only
Manual mode Brightness 5 steps. Adjustment of only the
center brightness is made.
Photo mode Brightness 5 steps. Adjustment of only the
center brightness is made.
Manual T/S mode Brightness 5 steps. Adjustment of only the
center brightness is made.
T/S Auto mode Brightness 1 step only
6 7 8 9 10 W
5 6 7 8 9 10 W
0.3 0.5 1.9
3 4 19 A
AL-2041 ADJUSTMENTS 9 - 4
E. Copy density adjustment procedure
Use SIM 46-1 to set the copy density for each copy mode.
For selection of modes, use the [Exposure mode selector] key.
(1) Test chart (UKOG-0162FCZZ) setting
1) Place the test chart so that its edge is aligned with the A4 (Let-
ter) reference line on the document table. Then place a A4
(14" x 8 1/2") white paper on the test chart and close the docu-
ment cover.
Test chart
(2) Perform the adjustment in each mode.
1) Execute SIM 46-01 (300dpi). To adjust in 600dpi, execute SIM
46-02.
2) Select the mode to be adjusted with the exposure mode select
key. Set the exposure level to 3 for all adjustment. (Except for
the auto mode.)
(1) (2)
0
Adjustment
mode
Auto mode Auto lamp ON
Manual mode Manual lamp ON
Photo mode Photo lamp ON
Manual T/S Manual lamp/Photo lamp ON "3" is slightly copied.
mode
Auto T/S Auto lamp/Photo lamp ON
mode
White paper
(1) Exposure mode select key/display lamp
(2) [Exposure mode selector] key/
display lamp
Exposure mode Sharp gray chart
display lamp adjustment level
"3" is slightly copied.
"3" is slightly copied.
"3" is slightly copied.
"3" is slightly copied.