I've been wanting to make a Rheobus for a long time now, but a lot of it has been very, very confusing. As far as I know, the potentiometers route a certain % of the volts one way and 100 minus that % ...
You can go to this SITE for a few different fan speed control projects but the fan controller I like best (and the one I built and use) is THIS ONE. Most fans won't run reliably at less than 40 or 50% ...
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