N_Cook wrote:
Jim Yanik wrote in message
...
"N_Cook" wrote in
:

Jim Yanik wrote in message
...
"William Sommerwerck" wrote in
:

In that are is what looked like an afterthougt 1W resistor to
ground, marked brown black brown. Surely not if a few hundred
volts there. With a good light brought into the area I could then
see it is brown black
purple.
Just an ordinary looking MO resistor, enamelled ,no glass
encapsulation,
but
1 Gigohm.
Wouldn't that be 100M? (10 x 10^7)



yes.

--
Jim Yanik
jyanik
at
kua.net
I'm not used to seing that colour combination.
Measured about 1000Meg, by comparison with a glass cased 1Gohm , with
a high voltage source, it is grey not purple on the third band on
rechecking.

I'm surprised it would stay 1G for any length of time,with an enamel
coating.

maybe you could post a pic of it.I wonder who makes them?

--
Jim Yanik
jyanik
at
kua.net

Its just a light blue bodied resistor that looks like any other except for
an unusual colour code. It must be there to discharge any accumulated charge
inside the developer chamber. A resistor with a crimp eye terminal at either
end, looking a bit afterthoughtish. Whether it is 500M or 2000Meg probably
does not matter. I imagine it could be difficult to make a high resistivity
spiral of metal oxide, from my own attempts at making resistive compound for
1 meg pot tracks, very patchy resistivity

As for main thread I got into the generator circuit and temporarily upped
the retract ? voltage up to 350V , for a test. Black lines still there and I
think the image intensty was reduced as well, ie wanted charged, latent
image bits, partially retracted back to the developer, so no solution there.

Apparently, from an industrial chemist, it is possible to get fine ground
pure carbon black from chemical supply companies for some sort of filters ,
not activated charcoal. All laser and copier toner these days have silicone
oil added , perhaps to avoid the use of silicone oil bath/wicks at the
output fuser stage. Enough oil carries through to the output to keep the
paper from sticking to the supposed non-stick finish of the fuser roller or
its pressure roller.

*NO!* That is NOT correct! Laser/copier toner is totally dry. The
silicon oil is applied to the fuser roller by a wiper pad, & serves to
prevent the 'cooked' toner on the paper from sticking to the fuser
roller as it exits the fuser assembly.

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
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