Each Tuesday is EducationTuesday here at Adafruit! Be sure to check out our posts about educators and all things STEM. Adafruit supports our educators and loves to spread the good word about educational STEM innovations!
Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !
A dual gang pot is a lot less likely to have around than one with a switch
You can also leave the pot unmodified, and use an NPN transistor in common-emitter mode as the switching element. Put 5V on the CW end and ground on the CCW end. Current limiting resistor from the wiper to the transistor base. As soon as the wiper reaches 0.7V, the transistor turns on. A pull-up resistor on the base can make it more sensitive (turning it on sooner in the rotation. Sounds like a lot of circuitry, but this can all be glued “deadbug” style on the back of the pot.