On Sat, 25 Jun 2016 10:03:32 -0700, Jeff Liebermann wrote:

Hmmm... 15 year old printer. Is it dirty inside?

If it's a thin black line, such streaks are usually caused by the
laser scanner or formatter electronics. Some dust on the rotating
mirror might do the trick (not sure). However, that doesn't quite
match your vague description.

The various rollers will leave their footprints, but not as a
continuous line across the page. However, if it's a broad smear, it
can easily be a burnt toner cartridge that was left in the sun, which
then burned the drum. A scorched fuser roller will do much the same
thing. Please heed the advice of others to measure the distance
between the horizontal lines, divide the distance by 2*Pi, which
should yield the diameter of the offending roller.

If you want to continue this, I suggest you take a photo of an
offending page, post it to a public photo site, so we can look at it.
Otherwise, make an effort to be more specific than "horizontal
streaks".

The manual is 10 dollars
https://www.tradebit.com/filedetail....service-repair

Free service manual:
http://www.lbrty.com/tech/Manuals_HP/3200sm.pdf

It's not dirty inside as far as I know what to look for.
In fact, it's pretty clean.

Here is a scan of a photo that was put in the slot long-side horizontal.
So the scan was vertical. http://i.cubeupload.com/dmSy3Y.jpg

Notice that the scan was from the top to the bottom of this picture
(from head to toe) but the "scratch" lines are from side to side (which
is not the direction that the paper moved).

There isn't any moving object side to side, is there?

(The horizontal scratches are not in the original photo!)