EMF detector

Again for the school-project-that-I-cannot-mention-explicitly-by-name-because-of-Google.

As an extra tool for us to use in our investigation into the unseen, I constructed an Arduino-based electromotive force (emf) detector. I’ve made breadboard versions of this before, but now it was time to build something a little more permanent.

barebones Arduino, 10 LEDs and a plastic case from a pound shop screw set

The LEDs light up in proportion to the strength of electromagnetic field detected. Since electrical currents are intrinsically linked with magnetic fields (can’t quite remember my A-level Physics) placing the antenna near to power sockets and electrical items light up some of the LEDs.

4-way gang lights 'em up

bing

The microwave seems reassuringly well shielded:

But my clock radio and bedside lamp are a tad alarming!

It’s very interesting hunting around the room for different effects. Orientation of the antenna changes the number of lit LEDs, as does switching things on and off. I’m curious to see how the detector responds to big classroom equipment such as smartboards and projectors, but of course the main point is observing how the children respond to being able to visualise things they wouldn’t otherwise be aware of.