Printer help?

From: Michael Sokolov <msokolov_at_ivan.Harhan.ORG>
Date: Thu Sep 9 20:24:15 2004

ard_at_p850ug1.demon.co.uk (Tony Duell) wrote:

> It worked. It still works. Pity I can no longer get toner for it (I am
> going to have to work out how to refill those cartridges, and what to
> use).

Something I've been wondering about too. But what about other parts of
the EP cartridge besides the toner, i.e., the photosensitive drum?
Doesn't it also have a relatively short life, a little longer than the
toner supply but not by much?

> Thing about mechanical problems is that you can often observe the unit in
> opeeration and see what doesn't move when it should (or does move when it
> shouldn't).

The problem is that the observed symptoms still don't translate into
a fix. Prior to replacing the job offset assembly on my NX, it had
the following problem when printing to the main output bin: the paper
would feed through perfectly fine, but just as it was beginning to emerge
from the last rollers, it would stop and the front panel would indicate
a jam. The paper was not jammed, and if pulled out manually the printout
was perfect. Obviously it was simply moving a bit too slow, and the DC
controller had very little margin in the number of clock cycles allotted
for the sheet to clear each sensor, causing it to barf. This much was
clear. The problem is, how does one go about fixing it? There was no
component I could directly lay the blame on.

Replacing the job offset assy fixed it, and while the practical side of
me is happy (the new assy was pretty and shining clean, the old one was
dirty and ugly to the sight and to the touch), the purist side of me,
the part of me that reads your posts and aspires to be more like you,
is still quite unhappy about the whole episode, since I never understood
WHY replacing the job offset assy fixed the problem, and what exactly
was wrong with the old one.

> FWIW, the DEC LN03 (I have one, I think mine is the Postscript model) is not
> a Canon engine...

I suspected that it was one of the rare exceptions, thanks for the
confirmation. BTW, am I correct in that LN03R is a pure PostScript
printer, i.e., PS ONLY and cannot work like a plain LN03? This would
make the LN03R quite different from the later LNs, and that is why
I've long felt that only the original LN03 is the real thing and that
the later LNs pale in comparison. And the later LNs are based on a
Canon engine, and I seem to recall a low-end cheapo one at that...
Don't remember what ?X, but I seem to recall it's the same one as in
"Personal" LaserJets and LaserWriters.

> Are the scanners the same? Normally the higher resolution scanner needs
> to rotate faster (so as to put more lines down in the same time). I know
> that on the CX engine there was a 415 (!) dpi version and a crystal on
> the sannner motor PCB [1] needs to be changed.

I thought the same, and the part swapper guide gives different part #s
for the IIISi and 4Si Laser/Scanner assemblies. However, a guy here in
San Diego who professionally repairs these printers told me that he had
swapped all kinds of parts between IIISi and 4Si that you are not
officially supposed to swap and it worked; only the formatter and the
DC controller are different he claimed. Maybe the scanner assembly has
some kind of switch or jumper inside?

MS
Received on Thu Sep 09 2004 - 20:24:15 BST