Brother MFC4820C Service Manual page 39

Step B: Alignment Check
(1) The LCD shows:
Check the 600 DPI and 1200 DPI test print to see if No.5 most closely matches the OK sample
(No.0). Press the 1 key if No.5 matches it.
If another test print number is a better match for either 600 DPI or 1200 DPI, press the 2 key
to select NO and go to (2).
(2) For 600 DPI, select the number from 1 to 8 that most closely matches the No.0 sample and
enter it using the dial pad.
(3) For 1200 DPI, enter the number from 1 to 8 that most closely matches the No.0 sample.
The Quality check is now complete.
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