[crispernaki]’s opening comments to this VCR head scroll wheel project lament that overall technical details aren’t “complex, ground-breaking, or even exciting.” Since when does that matter? The point is that not only did the thing finally, eventually get built, it gets daily use and it sparks joy in its owner.
This feel-good story is one of procrastination, laziness, and one aha! moment, and it’s roughly twelve years in the making. Inspired by an Instructable from long ago, [crispernaki] ran straight to the thrift store to get a VCR and take it apart.
The original plan was to just reuse the VCR head’s PCB and hide it in an enclosure, and then figure out way to block and unblock the path between an IR emitter/receiver pair. After many disemboweled mice and fruitless attempt, the project was once again shelved.
But then, [crispernaki] remembered the magnetic rotary encoder demo board that was just sitting around, along with various microcontrollers and Altoids tins. And it all quickly came together with a Teensy 2.0 and some bits and bobs, including a magnet glued on the shaft of the VCR head. A chip on the demo board does all the heavy lifting, and of course, the Teensy does the work of emulating an HID.