[sdiy] Do these things exist ? ( switch and pots )

[WeAreAs1 at aol.com]

In a message dated 8/13/04 4:01:10 PM, peng3002 at yahoo.com writes:

<< I was fantasizing about the Analog Solutions Phoenix last night. It has 
this articulation button that puts out 0-10V depending on how far down it's 
pressed. I'm wondering if there's such a thing as a spring loaded potentiometer 
that works by pushing in and out ?  If so, what's it called so I can search it 
out ? >>

There do exist "linear potentiometers", which are actuated by a sliding rod.  
I'm not sure where I saw them before, nor do I know how long the rod throw 
is.  They're probably designed for use in some kind of industrial/automation 
machinery, and if so, they'd have to be made to be pretty sturdy.  I don't recall 
is they were spring-loaded, but if not, I'm sure that would be fairly easy to 
remedy.  Try searching the usual suspects:  Alps, Bourns, etc.   Please let 
us know if you find any info about them.

I really wish we could more easily purchase FSR's (force-sensing resistors) 
for DIY use.  Interlink, the sole maker of FSR's, is not really 
hobbyist-friendly, unfortunately.  FSR's would make great pressure/velocity-sensing buttons 
and control surfaces.   I am preparing to build an electronic/MIDI marimba 
controller, and I would much prefer to use FSR's on the bars instead of piezos 
(yuck!).  All of the Kat drum and mallet controllers use FSR's that are 
custom-made by Interlink for those products.  If you've ever tried a DrumKat or 
MalletKat, you already know how much better they respond than the typical piezo-based 
drum pads.  It's because of the FSR's!

Michael Bacich