I Built a Microwave Transformer Arc Machine at 15

It was May 2022. My grandparents were getting a new microwave. Before it went in the trash I looked up what you could actually do with the parts inside, and the rabbit hole went deep fast.

The answer was: a lot.

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The Build

Microwave oven transformers — MOTs — have a secondary winding that puts out somewhere around 2,000 volts AC. That’s the voltage that drives the magnetron. It’s also, as it turns out, enough to throw serious arcs.

I pulled the transformer, grabbed two capacitors, wired it up, and made this.

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How Dangerous Was It

Genuinely the most dangerous thing I’ve ever done. Microwave transformers at full output can kill you. The capacitors store charge even after you disconnect power — touch the wrong thing at the wrong moment and it’s over. I was 15, working with components I barely understood, in my grandparents’ garage.

I don’t recommend it. But it was also one of the coolest things I’ve ever built.

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Microwave oven transformer, two capacitors, age 15. It arced. Please don’t do this.