I have a confession. One of my favorite YouTube rabbit holes to go down is ghost-hunting. It’s silly, I know, but it’s a paradoxically entertaining thing to watch- people applying scientific principles to the occult. If you’ve ever watched these videos or played Phasmophobia, you may have seen a tool used called a Spirit Box. Like a modern-day upgrade to the Ouija board, this tool scans through the local AM and FM radio waves rapidly, and ghosts can “talk” by causing certain words or phrases to pop out at you from the white noise. Halloween is fast approaching, and if you want to have some haunted adventures with your friends, you should pick up this Spirit Box.
At its core, this fully-assembled circuit uses an ATmega328P chip, with the ability to select if you want to forward-sweep or reverse-sweep through the frequencies in 100ms to 600ms intervals with a 10-step selection range. The FM band is from 64 MHz to the 109 MHz range, and the AM spectrum is listed as being set “as the widest AM bandwidth”, so some onsite testing may be necessary for that spectrum. A 128×32 OLED display shows you all relevant information, day or night, like your current frequency, battery percentage, sweep step duration, and signal strength. This product runs off of one 9V battery (a must-have in any pack-out bag, ghost-hunting or not!), and to get talking to spectres, you’ll just need that 9V, an aerial antenna, and a snug enclosure.
This phan-tastic circuit is brought to you by JasonKits, based in Malta. They have so many other projects available on their page, including some non-spectral AM/FM radio projects, and a litany of 3D printing upgrades and add-ons.
