Brother MP-21C Service Manual page 153

Adjusting Vertical Lines
If the vertical lines are not straight, carry out the Vertical Alignment
adjustment from the printer driver.
When you do this, load A4 or Letter size plain paper. For how to load
paper, see Chapter 2 in the User's Guide.
1. Select 'Maintenance' from the MP-21C series group in Windows .
2. Click 'Vertical Alignment.'.
If you are using the printer through the Printer Interface Card, the printer
will carry out adjustment for slow speed mode.
If you are using the printer with the AC adapter, the printer will carry out
adjustment for fast speed mode.
See Fig. 15 and Fig. 16 below. From the adjustment pattern page which
the machine has just printed out, select the pattern number which looks
most like Fig. 15 for both slow speed mode and fast speed mode.
Note
If you are not sure which number pattern is the right one, select the
one where the short and long vertical lines on the adjustment pattern
are matched or the closest.
If you can find more than one pattern in which the short and long
vertical lines are matched, compare the gray shaded part and select the
number pattern in which all the check patterns look the same.
When the AC Adapter is not connected, the printer carries out only
slow speed mode vertical lines adjustment. When you use the AC
Adapter, connect the AC Adapter and try adjusting the vertical lines
again from the driver.
If you cannot correct the vertical alignment at the first setting, you can
repeat the alignment procedure through the printer driver.
Fig. 15 Good Sample
Fig.16 Bad Sample
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