Phil Marlowe wrote in a message to Roy J. Tellason:

 PM>  Re: your laser problem...
 PM>  
 PM>  I haven't seen the complete thread and haven't a  clue about 
 PM> lasers but here's a quote from:  TROUBLESHOOTING AND REPAIRING 
 PM> COMPUTER PRINTERS,  BY STEPHEN BIGELOW -- TROUBLESHOOTING CHART:
 PM>  
 PM>  --------------------QUOTING-----------------------
 PM>  HOROZONTAL BLACK LINES ARE PLACED RANDOMLY THROUGH
 PM>  THE PRINT:
 PM>  
 PM>  1. check or replace the beam detect sensor
 PM>  2. check or replace the scanner assembly
 PM>  3. check all connectors and wiring from the scanner
 PM>  -----------------END-QUOTE-----------------------
 PM>  
 PM>  If this means anything to you, there may be more  info about how 
 PM> to go about the above in the book...  don't know since I refer to 
 PM> it for dot matrix info only. Let me know.

I'm not familiar enough with the innards of laser printers in general or
with the innards of this one in particular to know what those parts even
*are*,  but perhaps I can find out a bit more by disassembling it some more
than I have.  At this point if I open this one door I can pull the whole
assembly containing the drum out,  but I've not gone further than that. 
Not doing a whole lot of printing here,  it's not been a real high priority
with me,  but I'll get to it at some point...

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