Dodecahedron Speaker for Desktop 3D Printers

At normal listening distances, an array of twelve speakers arranged on the faces of a dodecahedron is a very good approximation of a point sound source, and the sound waves it produces are very close to perfectly spherical. A dodecahedron speaker can be a useful tool in acoustics research, and... Read more »

Evasive Beeping Thing

The Evasive Beeping Thing is appropriately named, since it dutifully does exactly what its name implies: it sends out a 5-second, high-pitched beep every few minutes. The source is extremely difficult to locate because of the way that high frequencies can penetrate objects and trick our ears. You’ve probably encountered... Read more »

Gigantic Bubble Generator

When I read the Geekcon 2010 call for projects, I thought, what the hack — I’ll do it. Inspired by Julia Cameron’s The Artist’s Way, I decided to let creativity into my life, and start inventing things. I watched Sterling Johnson’s magnificent “Giant Stinson Beach Bubbles” clip on YouTube, and... Read more »

Treasure Finder

Who hasn’t dreamed about owning their own metal detector and searching for buried treasure, or at least a few dropped coins? In this project, we will build a metal detector based on a dual oscillator circuit. One oscillator is fixed, and the other varies depending upon the proximity of metal... Read more »