Tune in to the electromagnetic frequencies around you.

The EMF Explorer Badge is a hands-on soldering kit that turns the invisible electrical activity of everyday electronics into sound. Walk around, listen, compare devices, and build intuition for the signals hiding in the modern world.

Ages 14+ Soldering Required Open Hardware No Experience Needed Components Included Educational Electronics
EMF Explorer badge illuminated, glowing green

What you're holding

An electromagnetic frequency sensing circuit that lets you listen to the hidden electrical world - the way Bluetooth hardware sounds when it's transmitting, how a laptop touchpad clicks under your finger, the hum of a power supply behind a wall.

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Hear the Invisible

Inductors on the board pick up EMF in the 20Hz–20kHz range and amplify it ~1000x into your headphones - frequencies your ears couldn't otherwise catch.

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Build It Yourself

A guided through-hole soldering kit. No previous electronics experience required - every part is labeled, every step explained.

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Wear It, Light It

Once assembled, it's a glowing wearable badge on a lanyard - light your path at night, then go sniff out signals with headphones.

Explorers in the wild

From hackerspaces to Maker Faires to Chaos Communication Congress - explorers have been listening to the world.

Kid listening to EMF from a wall outlet with the badge Explorer listening to a streetlight pole outdoors Holding the EMF Explorer badge outdoors in a park Listening to a parking meter's EMF emissions

Get your EMF Explorer Badge

Pick up a kit from one of these retailers, order a bare PCB, or build from the open hardware files.

Built for curious hands and curious minds.

Explore, listen, and learn your way through the invisible electrical layer of the modern world. EMF Explorer is open hardware, made with care by SporkLogic.

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