That's neat. It does remind me a few things. They're only related by this topic. 1. A buddy was experimenting with 3d printers, and was measuring the spin on a

That's neat. It does remind me a few things. They're only related by this topic. 1. A buddy was experimenting with 3d printers, and was measuring the spin on a magnet superglued on the back of a NEMA 17 shaft. He had weird interference going on. We eventually figured out the sensor was sensitive enough to measure the magnetic field in the stepper itself. Our solution was to take a spinning rust HD case, and cut/wrap it around the stepper. Spinning rust cases are made out of MU-Metal. Think of them as magnetic shielding. And in our case, it worked with nothing more than scrap we had around. 2. There was a company I ran across a year ago that was selling chips that could communicate over a personal magnetic area network. They didn't give hard numbers, but claimed they could transmit audio and video within a 2m bubble. They also worked through stuff like water (which kills most radio). I asked for some samples, but fell on deaf ears. I'd still love to have/purchase a few chips to experiment with.