Watch a Hacker Fry a Hair Dryer With Her Radio article shows that a handheld directional radio antenna can be used to to fry a ground fault circuit interrupter, or GFCI: GFCIs integrated into household appliances like hair dryers and heaters or wall outlets, mischievously switching them off or making the plugs shake, spark and melt from as far as ten feet away.
Jauregui’s trick isn’t exactly new: Electricians and ham radio enthusiasts have warned for years that some GFCIs are vulnerable to occasional radio wave interference. You just agitate these devices with radio waves for a short period of time and they overheat and blow up. Radio signal can cause GFCI just to trip, and on worst case make that internal switch vibrate without breaking the circuit completely (causes overheating in contacts). Newer designs of GFCIs are designed to be less susceptible to radio frequency, but old designs are still widely used.