Need to turn off fuser HP Laserjet 4L.

[Mike]

Archived from groups: comp.periphs.printers (More info?)

For some experiments I need unfused laser images.
I have an HP Laserjet 4L that I could use if I could turn off the fuser
and still have the rest of it work.
Can I shunt a thermistor and make this happen?
Schematics available?
Thanks, mike
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[martin]

Archived from groups: comp.periphs.printers (More info?)

Mike,

I really dont think that could work because if you turn off the
thermistor or whatever a fault will alert the printer logic board that
the fuser is going to either over heat causing a fire, or will not
heat at all and will give you a 50 error which is a fuser related
error, good thinking though!

Martin

 

[Guest]

Archived from groups: comp.periphs.printers (More info?)

In article <41922A20.9030909@netscape.net>, mike <spamme0@netscape.net>
writes
>For some experiments I need unfused laser images.
>I have an HP Laserjet 4L that I could use if I could turn off the fuser
>and still have the rest of it work.

Can you power off the printer before the page gets to the fuser and at
least recover a partial unfused image?

--
Tim Puffett

 

[martin]

Archived from groups: comp.periphs.printers (More info?)

No , this cannot happen, because when the paper is being fed into the
fuser the other half of the page i still going through the toner
cartridge.

Martin

 

[Guest]

Archived from groups: comp.periphs.printers (More info?)

In article <e05a06fe.0411150416.184f28c1@posting.google.com>, Martin
<martin@icanfixit.co.uk> writes
>No , this cannot happen, because when the paper is being fed into the
>fuser the other half of the page i still going through the toner
>cartridge.

It does depend on the model of printer and also how much of an image you
want / need to see. Obviously you aint gonna get a complete unfused page
by this method. Simply trying to trick the printer into completing a
cycle without any heat in the fuser is still likely to mess up the toner
image on the page as it a) passes through the (cold) fuser rollers or b)
as it wends it's way through the output rollers etc, or c) as someone
shakes it when picking it up to look at it!
--
Tim Puffett

 

[Mike]

Archived from groups: comp.periphs.printers (More info?)

Tim Puffett wrote:
> In article <e05a06fe.0411150416.184f28c1@posting.google.com>, Martin
> <martin@icanfixit.co.uk> writes
>
>>No , this cannot happen, because when the paper is being fed into the
>>fuser the other half of the page i still going through the toner
>>cartridge.
>
>
> It does depend on the model of printer and also how much of an image you
> want / need to see. Obviously you aint gonna get a complete unfused page
> by this method. Simply trying to trick the printer into completing a
> cycle without any heat in the fuser is still likely to mess up the toner
> image on the page as it a) passes through the (cold) fuser rollers or b)
> as it wends it's way through the output rollers etc, or c) as someone
> shakes it when picking it up to look at it!

Didn't get any useful info, so I just did it.
Ripped out the fuser. Put a 4.7K resistor in place of the thermistor.
Get about 80% of a page before it stops. Working great.
mike

--
Return address is VALID.
500MHz Tek DSOscilloscope TDS540 $2200
http://nm7u.tripod.com/homepage/te.html
Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
Bunch of stuff For Sale and Wanted at the link below.
http://www.geocities.com/SiliconValley/Monitor/4710/