Xerox Phaser 7700 Service Manual page 293

Halftones
This test prints 6 pages of 100% solid fill of:
Yellow, Magenta, Cyan, Black, Red and
Green. This print sequence is very useful in
determining if there is any streaking of
(usually) yellow or cyan that has interfered
with RegiCon (registration control).
When you get DC685-1 results showing
"A-Patch IN/OUT block counts" of less than
24 (or "B-Patch IN/OUT block counts" of less
than 4), use these prints to decide if
attention needs to be focussed on the toner
delivery mechanisms. Until toner is evenly
deposited on the developer roller, RegiCon
cannot pass.
Things to look for:
A "mottled" color, especially on the red and
green pages.
S7700-292
9-270 Phaser 7700 Color Laser Printer