Building a basic EMF detector for under £50 - is it worth it?

I've been looking at those commercial EMF meters and they're all like £80-150 minimum, which seems mental for what is basically just a sensor and some lights. So I started wondering: could you build one yourself?

I've been tinkering with Arduino projects for a bit, so I grabbed some parts from eBay (coil, amplifier module, Arduino Nano, some LEDs) for about £45 total. Spent a weekend putting it together and honestly, it seems to work? I tested it near my telly and microwave and it picks up electromagnetic interference like it should.

Question for the more experienced folks: is a DIY one going to be accurate enough for actual ghost hunting, or is it basically a toy? And if anyone else wants to have a go, I can post a parts list and rough schematic. Might save some people a fair bit of cash.

Yes! Please post the parts list. I'm not great at soldering but I reckon I could manage basic assembly. How reliable is it compared to the proper Mel-meters everyone goes on about?

is a DIY one going to be accurate enough for actual ghost hunting

Honestly, most commercial EMF detectors are overpriced gadgets anyway. Half the paranormal investigators I know just use them for show. Your homemade one will detect fields just fine. The real trick is knowing what readings to pay attention to and what's just interference from power lines.

I tried this exact thing two years ago and the Arduino kept giving false positives near anything electrical. Fair play for trying but I'd just save up and get a proper meter. Not worth the faff of troubleshooting when you're trying to investigate something creepy, you know?

This is brilliant. What Arduino model did you use? And more how did you calibrate it? That's the bit I always get stuck on with DIY stuff.

Have you tested it at any allegedly haunted locations yet? Be interesting to know if it picks up anything weird compared to baseline readings.