[sdiy] Piezo keyboard

[harrybissell]

Of course if any of you looked at the link to the ThereminVision system... you
would
shirley see the basis for a scanning capacitive sensor system....

which I will be experimenting with TODAY !!!

Maybe a polyphonic theremin is in the offing (prlly NOT) or maybe a V-shaped
antenna system
that allows two simultaneous CV with hand position ???

For Peter's  app... you might need to use some kind of micro to scan which key /
keys were
closest to the finger of interest... I suspect they will be too close to really
be separate.

H^) harry

Peter Grenader wrote:

> john mahoney wrote:
>
> > I don't know if the anodizing has to be removed or not -- is it an
> > insulator? Since it's a natural color you wouldn't see much difference
> > either way. However: Bare aluminum gets covered by a thin, black oxide that
> > isn't very visible -- until it's all over your fingers. Yuck!
>
> Yeah, I don't know.  When I mentioned that in my last post I was thinking
> "am I full of it right now?' when I was typing it.  Because you're right -
> aluminum being a passive metal, the oxidation layer happens anyway just by
> it being in contact with air. The anodize is nothing more than a tinted
> layer of induced oxidation that takes the place of the one that would occur
> naturally. so possibly the anodize would be OK.
>
> But what just came to me,  which would be WAY cool:
>
> What if the capacitance thing worked - THEN I could have two functions per
> key.  One with light pressure and a second when you pressed a bit.  Like
> upper and lower case. This would be really interesting if you ask me.  Two
> voltage pots per key.  hmmmmmm....
>
> OK, look -I've done a touch key response circuit which passes a high when
> it's touched.  Currently it's connected to a quarter.  If it still works
> (been in the pile for some time, you know how that goes) I'll try it with
> these switches and see. I'll get back to ya all.