MonoBox Powered Speaker
Learn how to build inexpensive powered speakers that amplify the output of your headphone music player. It may be small, but this speaker can still rock!
Power jack
Secret-Knock Gumball Machine
Make a cute candy vending machine that only dispenses treats when you knock the secret rhythm on its front panel.
Cellphone Car Ignition
Remote-start your ride from any distance, sans key fob.
Geiger Counter
This DIY Geiger counter clicks and flashes an LED each time it detects a radioactive particle. It works with most common Geiger–Müller tubes, and easily connects to radiation rate meters, data loggers, true random number generators, and the Radiation Network’s GeigerGraph software. Share your radiation readings with the whole world!
Lunchbox Laser Shows
Back in the 1970s, my friend Wayne Gillis and I used to do light shows at science fiction conventions. We had the usual panoply of overhead, slide, and custom-made projectors, and a single, very expensive, helium-neon laser from Edmund Scientific. Calling ourselves Light Opera, and later, Illuminatus, we performed at ConFusion conventions in Ann Arbor, […]
