Buchla/Serge Keyboards

[honcho at paia.com]

>Has any one built or tried to build touch plate keyboards like the 
ones 
>on the Buchla/ Serge Mods.If so what contact/conductive material did 
you 
>use for them,and does anyone have any (detailed) plans.
>>>

Late off the line, as usual, but I hope this thread is not yet so cold 
that anyone will mind me saying:

Wow, I didn't know Buchla had a product likes this. This is the way 
the finger pads of PAiA's Programmable Drum Set worked.  It's 
difficult to find any cheaper solution to lots of buttons when you're 
doing a design that will be manufactured in small quantities (like 
one, f'rinstance).

We had very good luck with etching the pads on the circuit board and 
then screen-printing over the copper for protection and to legend the 
pads as well. The board was single sided, so the components were 
"upside down" when the board was installed in the case.  It's pretty 
easy to see what I'm talking about on the larger PDS photo in our 
photo album http://www.paia.com/fotoalbm.htm . When covering the pads, 
the thinner the covering the better (which is why a layer of printing 
ink works well). I remember that Scotch Tape worked OK on the 
prototypes so probably laser printed mylar sheets would be an 
attractive one-off approach.

It surprised me a couple of years back when I realized how easily 
these pads can be made pressure (velocity) sensitive. 

If anyone's interested in seeing the circuitry for these, let me know 
and I'll put it up under "accretion" in the next few days. 

-John

---------------------------------------------------------
John Simonton                  PAiA Electronics, Inc
3200 Teakwood Ln.              honcho at paia.com
Edmond OK 73013                http://www.paia.com
405-340-6300                   fax 405-340-6378