Existing Arduino tachometer code that is flowing around the internet give erratic readings even when the IR sensor is properly debounced. They are not useful for speed sensitive devices like a ...

Uses hall effect sensor for detecting turntable speed. Place a magnet on the turntable near the outside edge and turn it on, then hold the tester in a place where the magnet will move under the hall ...

This device created by student designers Yingjie Bei and Yifan Hu only looks like an artsy turntable, but it can't play your vinyl collection. Here's what it can do, though: show you the right moon ...