> --- In Homebrew_PCBs@yahoogroups.com, Lez <lez.briddon@> wrote:
>
> Mine(900) has a painted white square at the front, and next to it a
> notch cut out, I dont know if its looking for a reflection from
> white
> and then no reflection from the notch, or if its no reflection on
> black, reflection on white, then a sensor under the notch.
>
> I have tried on pcb (shaped like a cd...) but its not good, very
> uneven and lots of beading, but I have not got new ink yet, still
> waiting for the cis system
>
I'm pretty sure this is exactly what happens. If you lift the lid and
watch as it tries to sense the CD, the printhead runs over the white
squares (there's a blueish light underneath it, the paint might be
UV), and if it doesn't line up with them, it ejects the tray. It
doesn't look like it looks at the CD itself at all. It /may/ check the
CD after it checks the white spots to make sure there's a CD in the
tray, but I'm not sure about that one.
It can be irritating, because the feed rollers will often misalign and
you sometimes have to stick the tray back in several times before it
will accept and print. Get that tray replaced as soon as you can, my
R340 died in less than 3 months, the rollers that the tray is supposed
to go under towards the back of the printer stopped lifting, and the
tray would slam into them and instantly get rejected.