Derek Cowburn wrote:
>
> I need a small, single-turn pot that has a long wiper life and low noise
> during travel.  Something like a servo feedback pot, but tiny.
>
> Are there any non-contact components (optical?) that can accomplish this?


Yes, a tiny (good quality) trimmer capacitor.
Multi-plate work best, people have said that the top/bot
plate ones are too low (a few pF) and accuracy is bad.
I have found the large ones from transistor radios are
excellent for position use, the only hardware is one
schmitt inverter 7414 (as a high speed osc) etc and one
resistor and cap. So you can get 6 rotary sensors driven
with one 7414 chip. Then check the osc speed by counting
pulses/PIC clocks or vice versa. Accuracy is good for
8 bits or so.
-Roman

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