Re: Problem with AppleColor composite monitor

[sirarlias@webtv.net]

Hello everybody (again and again...).

I switched the red and green output wires from the main board and the
result on the screen is green where there should be red. There is full
control of green at the "red bias" trimpot. There is however no red
where there should be green and no control of red at the "green bias"
trimpot (other than that slight vertical compression I mentioned in my
original post.)

Since a signal made it through the "red" circuit on the main board, went
through the "green" circuit on the chroma board, then "fired" ;) the
green gun, the main board "red" circuit checks out. We already know both
the main board and chroma board "green" circuits work when the inputs
are correct. So the problem is either with the "red" circuit on the
chroma board (hopefully) or with the red gun itself (hopefully not).

Rubywand, I'm using an analog multimeter. (That's all I have available
at the moment.) Also, there are no trimpots on the chroma board. I'll
keep probing the components to see if I can find any differences between
each respective circuit.

I know one way to determine whether it's the red chroma circuit or the
red gun would be to somehow switch the red and green outputs from the
chroma board. But this would be clumsy and somewhat dangerous.

-+-+-+-

Thanks for your continued help!

-RPM