Roman Black <fastvid@EZY.NET.AU> wrote:
>I think the estimate of 200,000 times to 5% resistance is
>a bit fanciful, we get many TV and VCR remotes that are worn to
>failure within two years. I would say maybe 50,000 times to
>failure or even worse.

Actually as David has said, using gold plated fingers, a silicone (good
quality) keypad and rigid keycaps in a sealed environment will make it
last. BUT the price tag of all this will be higher than membrane or
pushswitch keyboards for small sizes (as used on PIC projects).

For large keyboards, it pays to go rubber. I am pretty sure that an
amazing proportion of the piclist members type their messages on
rubber-based keyboards (with keycaps and mechanical guides).

One of the keyboards I liked for innovative design was the IBM portable
computer's which was a Hall sensor keyboard with springs that caused a
small magnet to stand or lie on the Hall sensor. The Hall sensor was
printed directly onto the PCB using thick film technology ;-) These did
fail sometimes (the mechanical part) but they were great fun to use.

Peter

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