Xerox Wide Format 6705 System Manual page 305

ADJ8.1.5.3 LPH Joint Fast Scan Direction Adjustment
Purpose To eliminate the image misalignment (white streaks or black streaks) in the fast scan
direction for the 3 LPH.
Note 8.1.5.1 LPH Focus Rough Adjustment and 8.1.5.2 LPH Density Difference Fine
Adjustment (Light Duty Adjustment) must already be adjusted correctly.
Check Procedure
1. Load A0 (36") roll paper into Roll 1.
2. Enter the Diag Mode and select IOT DC606 Test Print.
3. Print the Test Pattern by using the following parameter settings.
• 1. Output Image : LPH Adjust
• 2. Quantity : 1 sheet
• 3. Paper Supply : Roll 1
• 4. Media Cut Mode : Fixed Landscape
4. Check for image misalignment (black streaks (overlapping direction misalignment) or white
streaks (gap direction misalignment)) at the joints if the 3 LPH (Figure 1: between E1 and F1,
E2 and F2).
Adjustment Procedure
1. Use IOT DC131 NVM Access to change the following NVM values until the image
misalignment (black streaks (overlapping direction misalignment) or white streaks (gap
direction misalignment)) at the joints if the 3 LPH are eliminated.
Note Compare the black streaks or white streaks that are visible at the check location with
the sample at G section in Figure 1 and change the sample value (step value) that is
the closest.
(Value after change) = (Value before change) - (sample value (step value)).
Changing the value in the positive direction shifts the image in the gap direction, while
changing it in the negative direction shifts the image in the overlapping direction.
• When black streaks (overlapping direction error) occur between LPH 1 and 2:
Change the value of 910-408 (LPH 1 (left image) Fast Scan Shift) in the positive
direction.
(1 step = 0.0141 mm (1/3 dot))
• When white streaks (gap direction error) occur between LPH 1 and 2:
Change the value of 910-408 (LPH 1 (left image) Fast Scan Shift) in the negative
direction.
(1 step = 0.0141 mm (1/3 dot))
• When black streaks (overlapping direction error) occur between LPH 2 and 3:
Change the value of 910-409 (LPH 3 (right image) Fast Scan Shift) in the positive
direction.
(1 step = 0.0141 mm (1/3 dot))
4.3 Error! Reference source not found.
Chapter 4 Disassembly/Assembly and Adjustment
• When white streaks (gap direction error) occur between LPH 2 and 3:
Change the value of 910-409 (LPH 3 (right image) Fast Scan Shift) in the negative
direction.
(1 step = 0.0141 mm (1/3 dot))
2. Save the NVM settings.
Note If the settings is not saved, the changed setting will be lost once the power is turned
OFF.
3. Return to Check Procedure, check whether the black streaks (overlapping direction
misalignment) or white streaks (gap direction misalignment) at the joints of the 3 LPH are no
longer noticeable and, if they still are, repeat the adjustment until they are.
910-408 (-)
910-408 (+)
910-409 (-)
910-409 (+)
(Figure 1)
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