Keyboard Encoder

[Harry Bissell]

can you say
"LVDT" ?

H^)

patchell wrote:

>     I am working on a keyboard encoder I had an idea for a long time
> ago, but never tried. (this will go into the Paia 8700 keyboard I am
> rebuilding).
>
>     It consists of a 5/16 in OD styrene tube, about 1.5 inches long.
> The I.D. is 1/4".  On this tube, I wrapped two coils, about .75" long on
> each have of the tube.  Inside the tube, I run a 1/4" Dia ferrite rod
> that can move back and forth.
>
>     I apply a fairly high frequency signal to one coil, and look at the
> output from the other coil.  As you move the ferrite rod into the tube,
> the signal on the output increases as some function of the position.
> (Not exactly linear, but that is not really important, I think).
>
>     Anyway, now that the idea at least shows promise, I will have to see
> what I can do to make it come to life.  There are a few mechanical
> problems that need to be solved (I am not much of a mechanical
> engineer).  Plus, I am not sure exactly how to apply this to a keyboard,
> but, I am sure I will come up with something.
>
>     **This was the perversion of the 8700 I was refering to in a
> previous post.**
>
> --
>  -Jim
> ------------------------------------------------
> * Visit:http://www.silcom.com/~patchell/
> *-----------------------------------------------
> *If you didn't buy a home in Santa Barbara,
> * You didn't pay enough!
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