[sdiy] [AH] Buchla joysticks

[Grant Richter]

> If Grant ever wonders why the joystick photocells in the machine he acquired
> from B-303 were unoperational - I was told it was intentional - John Payne
> killed them because of constant complaints he was getting about this
> problem.  The funny thing is, our professors simply told us the joysticks
> 'didn't work' - so we barely touched this module, which was quite
> unfortunate.  It wasn't until my second year that I tested this proclamation
> only to find they worked just fine, accept the photocells were kah-put.
> 

Well, the bulbs were burned out, but I replaced them and all 4 seem to be
working fine. That is as fine as they are going to. The mechanism is a white
ball with a plastic rod through it. The white ball reflects and the plastic
rod forms a "dark spot". There is a bulb in the middle and 4 photocells
arranged top and bottom and two sides.

The photocells form a voltage divider, you bend the photocell leads to
adjust for a 0-15 volt range. It was a tremendous amount of engineering to
make a light up joystick shaft. The plastic shaft also does not conduct heat
away from the fingers like an aluminum shaft.

Another example of Don's commitment to placing engineering in the service of
Art, rather than the other way around. That is not to imply that engineers
are not artists. Creative people tend to be creative on many levels, both
technical and aesthetic. I think this group is the perfect example.