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Author Topic: Servo and 10K Pot  (Read 462 times)
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I've got a servo running with analog input from a 10K Pot that reads out the converted value of the pot's resistance to appropriately position the servo.  That's fine and dandy.  My problem comes in where some positions in the potentiometer seem to allow both the servo motor and the output value to fluctuate within +/- 1 degree.  So that's telling me that the resistance at those points are not exact or something is fluctuating within the circuit, perhaps noise.  What can be done about this?  I'm thinking a cap maybe, but forgive me, this is my first electronics project.
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Possibly cheap/bad pot.
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Consider the daffodil. And while you're doing that, I'll be over here, looking through your stuff.   smiley-cool

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What can be done about this?


Never assume a analog input value will hold a constant count at all times even with a constant voltage applied, too many noise sources and other variations. It can often be handled in your software sketch by doing several reads, adding them up and dividing by the number of reads. That will give you a smoothed averaging result and is not too hard to implement. Give it a shot.

Lefty

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Add a cap from your pot wiper to ground, maybe 10uF.  Also, make sure your ADC reference has good capacitance on it.

Jacob
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