On Sat, 19 Nov 2005 00:00:08 -0700, Hamad bin Turki Salami
wrote:

I have an E-mu electronic music keyboard that was damaged when someone
spilled a drink on it. Four of the keys stopped working after the mishap.

The keyboard works, I believe, by the same principle as a capacitative
computer keyboard. When you press on a key, a black circular part
plunges against a circuit board which has at the point of contact a
corresponding pair of interlocking metal plates (embedded in the board).
I believe the interlocking metal plates are acting as a capacitor, and
the black circle is some kind of insulator that gets between the
plates and changes the capacitance.
[snip...snip...]

I think that you'll find that it's even simpler than that. The pair of
metal plates are simply connected to a "row" and a "column" in the
keyboard matrix and the contact is made by a conductive patch on the
base of the key plunger.

Cleaning the spilled drink probably removed the conductive coating. Try
painting the contact patch area with a conductive paint. Radio Shack has
p/n 640-4339 that would probably work, as would the conductive paint
from a "rear window defogger repair kit."

--
Rich Webb Norfolk, VA