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Subject: Re: [Homebrew_PCBs] homebrew rotary multi-position switch

From: "Roy J. Tellason" <rtellason@...>
Date: 2004-08-31

On Monday 30 August 2004 10:41 pm, ron amundson wrote:

> So what I gather, is a guy could put a good sized weight on the shaft to
> create inertia and give a perception of quality, then use optical
> interrupters to capture disc position?

Capturing the _change_ in position is more like it, depending on where the
software that was dealing with it assumed was the position to start with.

> I've looked at the mechanical rotary encoders in the past, but even in
> volume they were a couple bucks. The idea of using oprtical is quite
> interesting. I'd completely forgotten that is the basic mouse concept.

I have a couple of dead ones here that I'm thinking about playing with at some
point...

It's interesting to note that the LED/Detector pair on these is discrete
components. I also have some optointerrupters I'm planning on trying to do
something with that I salvaged out of dead floppy drives. Also some similar
parts which apparently were designed to use a reflective principle.

> All one would need to do, is add some type of position encoding to the mouse
> wheel, and one would be all set.

Nah, that'll all be handled in the software. As would the resolution, for
that matter.