Capacitors

Lunchbox Laser Shows

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, […]

One-Ton Linear Servo

One-Ton Linear Servo

RC hobby servomotors were just made for hacking. What’s not obvious is how much you can hack them — with a few tricks, you can use a servo to control almost anything. Hobby servos consist of a DC gear motor, a potentiometer (usually 5K), and a control circuit. The output shaft is the output of […]