Horizontal Sync Control - Canon CP660 Service Manual

Note:
1. Sampling Mode
In APC control, when the LENB* signal is '0' and the SAMPLE* signal is '0' (i.e., the
unblanking signal UBLON used to generate the SAMPLE* signal is generated by
the GA), the DATA* signal is forced to go '0'.
2. Hold/Print Mode
In this mode, the laser intensity resulting from APC control is retained. When the
SAMPLE* signal is '1' and the LENB* signal is '0', C1004 retains the laser intensity
in the form of a voltage without regard to DATA* signals.
When video signals are received, the laser diode is turned on and off according to
the DATA* signals.
3. Clear Mode
When the LENB8 signal is '1', the C1004 is discharged without regard to DATA sig-
nals* and SAMPLE* signals.
D.

Horizontal Sync Control

The optical path for the laser beam is equipped with a small fixing mirror (BD mirror).
The laser beam reaching the scan start position during the unblanking period is reflect-
ed by the BD mirror and directed to the BD PCB inside the laser/scanner assembly.
When the laser beam arrives, the BD PCB generates BD signals (BD*) for transmis-
sion to the GA (IC204) on the DC controller PCB. The GA uses the BD* signals to gen-
erate horizontal sync signals (LSYNC*), and sends them to the printer board.*
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* Reader controller PBC (when making prints with the reader unit installed).
COPYRIGHT © 1999 CANON INC.
Download free service manual at http://printer1.blogspot.com
CANON 660/2100 REV.0 FEB. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 3 LASER EXPOSURE SYSTEM
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