Michael Park wrote:

> I picked up one of Forrest Mims III's mini notebooks at Radio Shack,
> "Electronic sensor circuits & projects". He has some ideas for making
> switches out of pcbs or copper clad boards (for instance, a sensor in
> which
> vibration causes a wire to touch the copper. Anyway, long story short,
> I'm
> thinking of doing something similar, essentially building a pushbutton
> on a
> pcb (a piece of metal that, when pressed, bridges two pads on the
> pcb), but
> I'm worried that the copper might oxidize or something, preventing good
> electrical contact.
> Any thoughts on the likelihood of that happening? Any ideas to prevent
> it?
> Maybe some sort of conductive coating for the copper?

I recall an article Don Lancaster did for Radio Electronics (early '70s)
that used
conductive foam to bridge the pads.

Jim

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