Building a basic EMF detector for under £30 - full parts list and code

Right, winter's coming and everyone's going to be out investigating haunted locations when it gets properly dark. Might as well have decent kit. I've been tinkering with EMF detectors for a few years and finally got a reliable build that costs pennies compared to commercial units.

What you need:

- Arduino Nano (£8-12 from AliExpress)
- 3.3V buzzer (£1)
- LED strip (red, £2)
- LC antenna coil (DIY or buy pre-wound, £3)
- 9V battery connector and box (£3)

Total: roughly £25-30

I've written the Arduino code to detect electromagnetic fluctuations and calibrated it against a commercial unit. The sensitivity's adjustable, and you can swap components depending on what sort of interference you're hunting. Much more reliable than those cheap knockoff K2 meters everyone uses.

I can upload the code to GitHub if people are interested. Fair warning: you'll need basic soldering skills and a tiny bit of programming knowledge, but nothing mad.

This is brilliant. Been spending £150+ on proper EMF gear and half the time it's just picking up the local phone mast. Would definitely appreciate the GitHub link. Do you have build photos?

Seems like a decent project. One question: what's your false positive rate compared to the commercial units? EMF detectors are notoriously dodgy for actual paranormal work because everything electromagnetic gives them a fit.

Absolutely do this mate. I'm planning autumn investigations around Yorkshire Moors and my K2 is garbage. Been looking at upgrading and DIY is definitely the route. Please share the code.

Good work, but be aware that building your own equipment means you lose the 'standardized methodology' advantage in group investigations. Not saying your build is wrong, just that it might not mesh perfectly with established protocols if you're collaborating with other researchers.