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Originally Posted by Kirk
We are looking for some potentiometers that are a little more precise then the ones you get at radio shack. We also need something that will turn more then 4 revolutions. Any suggestions would be greatly appreciated.
Thanks in advanced,
Kirk Oden
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The Radio Shack pots are quite noisy, and can momentarily open
while you turn them, leading to bad behavior. We use very nice
pots made by Bourns, available from Digikey. For the 270 degree
pot, we use Digikey part number 3852a-282-104a-nd, about $9.
For the 10 turn pot, we use Digikey part number 3541h-1-103-nd,
about $28. The particular ten turn pot is chosen so that its "value
steps" are much smoother than the quantization error of the robot
ADC. The 10 turn is a 10K ohm pot, you need to connect the
normally open end to ground through a 500 ohm resistor to avoid
the OI's jump to 127 upon seeing zero volts behavior.
I did not find a nice 100K 10 turn pot. I did look for them...