Ultrasonic electron diverter
From Tardis Wiki, the free Doctor Who reference
Stan, a Celestial Intervention Agency field agent, owned an ultrasonic electron diverter, a small sonic device capable of temporarily deactivating all electric devices within a given small area. To prevent accidental activation, a key piece in the shape of a ring could be separated from the handle when the device was not in use. (PROSE: Tabby Cats And Time Lords)
