The idea is to more accurately point the Red and Blue CRT’s (CRT Angle) so
that these crosshairs line up without any electrical adjustments.
Second
, the optical assembly must be placed at such an angle (Lens Angle)
that the light travels equidistant to the screen from left to right. Top to
bottom adjustment is handled within the optical assembly but we can
improve on that too.
So, essentially, we must adjust the Lens Angle (by adjusting the Lens Space)
and the CRT Angle (by adjusting the CRT Spacer). These are not
adjustments for the timid so please be prepared to open a very large can of
worms if you start this. I really can’t stress this enough.
The problem with the factory system is that it is designed for a range of
screen sizes. If you want perfect focus, as most of us do, this is
unacceptable. The thin plastic spacers (blue arrow) are designed put the
CRT face at certain distance from the lens to provide the proper focal length
for the optical system for the screen size/throw distance.
I’ve come up with a simple fix that will allow for very fine adjustment of lens
flapping, but will take significant amount of time to set up as installation will
be difficult and adjustment much more difficult. A second person is definitely
a good idea.
