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Unread 16-11-2004, 10:39
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Re: Odd How a Thread About Spikes would be all about Victors

Quote:
Originally Posted by Mike Betts
I have never had to calibrate a Victor. We check the trim on the joystick trimpots before every match and, if necessary, retrim to "zero" (PWM = 127 when your hands are off the joystick). After trimming, we use electrical tape to "clamp" the trim and keep the operators from accidentally hitting the trim wheel during a match.
Mike - It was always my understanding (please correct me if I'm wrong) that the calibration was to allow for variations in the actual range of the joystick. If the upper value of the internal pot is 90 ohms (10% tolerance on 100k...may differ in practice), the highest value that your speed controller would ever see would be 228. That puts a clamp on the fastest you can ever drive that speed controller, and in return, motor if you were to not calibrate.

What the calibration does, as I understand it, is scale the way the inputs are converted to outputs. In the above example, after calibration, a value of 228 as an input will cause the speed controller to drive full forward, and a value of 114 would be the neutral value.

Can somebody either confirm this or smack me upside the head?