Peter L. Peres wrote:

> >Thanks Alexandre, that is handy info. The design
> >will tolerate 100 ohms per contact or so, but i'm
> >still nervous about contact change in resistance
> >over time. Would be nice if someone could say
> >"yes definitely about 100 ohms new, then increasing
> >to 300 ohms after 10,000 presses etc". :o)
> >-Roman
>
> Okay, here goes: Yes, definitely around 50 ohms new, some 5% increase
> beyond 500 ohms after 1000 or less presses and/or two months.


Thanks Peter, but ouch! That resistance increase is
not good! What type of keypad, and are the "bad"
buttons the most used or is this a random effect?
-Roman

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