Jeri’s Brainwave-Activated Light Bulb

One of my fave devices at Maker Faire Bay Area was (the future Mrs. Gareth Branwyn) Jeri Ellsworth’s “Brain Bulb,” a light bulb poised over her head which could read and respond to her “brain waves.” Here she describes the basic hardware and circuit design behind the device. The circuit is built around a low-power Analog Devices AD620 instrumentation amp.

Jeri (and some guy whose name I don’t recall) and her Brain Bulb at Maker Faire


Gareth Branwyn is a freelance writer and the former Editorial Director of Maker Media. He is the author or editor of over a dozen books on technology, DIY, and geek culture. He is currently a contributor to Boing Boing, Wink Books, and Wink Fun. And he has a new best-of writing collection and “lazy man’s memoir,” called Borg Like Me.

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