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N_Cook N_Cook is offline
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Default Key contact restoration

On 16/01/2016 18:44, Jeff Liebermann wrote:
On Sat, 16 Jan 2016 10:32:36 +0000, N_Cook wrote:

Is it simple on/off contacts or is change of R monitored for key "action"


http://oi65.tinypic.com/14xdmo3.jpg
The piano keys on a synthesizer might require some form of velocity
sensing which most assuredly is NOT resistive. The buttons in the
above photo are for turning things on/off and are therefore simple
on/off connections.
http://www.dummies.com/how-to/content/key-feel-and-response-of-keyboards.html




I don't know how many contacts are required.
I just tried taking a standard simple 10x10mm footprint click switch
apart , parts just clipped together. Cutting a disc of thin 1mm
silicone rubber, placing over the dome contact and reassembling , the
click noise and abrupt click action disappears, but still functions.
If they can be soldered to the pcb, ignoring the resistive pads, then
only a matter of fudging the right size and height of top protrusion to
glue over the stem of the switches,if necessary .
Well thats my halfpennyworth