Tektronix Phaser 840, Quick Reference Manual

Page: 149 / 160

Service Guide
139
11: Head-to-Drum Gap . This print
indicates if the gap between the printhead
and the drum is correct.
Lines . The horizontal lines of the print are
made up of long lines and short dashes. If
the dashes are positioned above the lines,
then the drum gap is too wide.
If the dashes are positioned below the
lines, then the drum gap is too narrow.
Also examine each end of the band of
text. Look for differences between the
quality of the characters on the left and
right ends of the print. A difference
indicates the printhead is misaligned.
Text . Look for text that is fuzzy or text that
differs in quality from one side of the print
to the other. Either conditions indicates
the printhead-to-drum gap is incorrect.
Perform the procedure “Printhead-to-drum
spacing adjustment” on page 66.
0388-39
Time_to_Drum/Head_to_Drum test print:
Short dashes above the line indicate large time_to_drum and/or large head_to_drum gap.
Short dashes below the line indicate small time_to_drum and/or small head_to_drum gap.
EFGHIJKLMNOPQ
EFGHIJKLMNOP
EFGHIJKLMNOPQ
EFGHIJKLMNOPQ
EFGHIJKLMNOP
EFGHIJKLMNOP
Indicates
that head-to-drum
gap is too small