Does this pot exist?

--Howdy! I've been fiddling around with using a pot to position a "servo". I'm using the teeny weeny one from Parallax that needs to be
turned with a screwdriver. The application is to drive one of those surplus windshield wiper motors; I'm using the PWM output to send signals to a Victor motor controller and this is working very well. --The trouble is determining, with certainty, that the motor is in "neutral". What I'm trying to do is use the motor as a winch to move a small load up and down on an art car I'm building. The winch will position the load one way when the vehicle is in motion and in another when it's parked. Although it's tempting to use a DPDT switch, I'd prefer to control the rate of the load's position change with a big, easy to grasp knob on a pot that could be located a few feet from the Stamp.     --What's needed is a tactile feedback of some kind so that I know when the motor is in "neutral", so that the motor isn't creeping. Text and photos of project to date at: www.nmpproducts.com/artcar.htm.     --TIA,
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If you are controlling everything with a basic stamp anyway, you can create a dead band around the middle of the pot position. Meaning, use the A/D converter to get some number between 0 and 255, 128 being the 'center'. Now, don't move the motor unless the value is below 120 or above 136, for example. Then put a nice 'click' in the lever sytem, so it won't drop down when you ride through playa potholes... .
Yeah, BurningMan is addictive. This little car worked for DPW among other things: http://matthiasm.com/trailerbitch /

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two shmidtt triggers, set to different voltages with a window in between, then if the voltz are tween the two set points you can have a relay or something that switches in some hard wired resistors, but it's certainly not the easiest way to go. maybe mod the pot, add a set of contacts internally that are at about centre travel.
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