diy projects

Build It

Build a Pocket Theremin on the Cheap

Throw together this pint-sized light-sensitive Theremin for spooky sci-fi sound effects on the cheap

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Even if you're not familiar with the Theremin itself, it's very likely you've heard its loopy electronic tones before. Remember those spooky sound tracks from 1950s science fiction movies? Well, chances are pretty good that those oscillating noises were generated by a Theremin.

Designed by Russian physicist Leon Theremin circa 1919, the two-handed instrument was one of the first ever electronic musical instruments and the first instrument one could play without physically touching it. Thirty years after its invention, the Theremin was popularized by American synthesizer godfather Robert Moog in the 1950s and immortalized in the classic Sci-Fi flick The Day the Earth Stood Still.

A full-fledged Theremin will set you back nearly $400, but with the instructions below, you can build a pocket-sized Theremin-like instrument that wont break the bank. Unlike the real McCoy which relies on grounded variable capacitance for changing frequency and volume with the wave of a hand, our Pocket Theremin uses variations in light for producing its unearthly vibrato.

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Build a Portable Password Generator

Convert an AVR development board into Pass Key—a handy dandy password maker

PINs, passwords, secure entry systems; just about everything you access these days needs some form of passive authentication code. Heck, even that Wi-Fi router in your basement uses a mega 63-character password for enabling secure access. Before you know it, youll even need a password just to go to bed at night.

More often than not, these security code systems require you to enter a lengthy 8- or more digit alphanumeric sequence. And creating powerful, unique, protective passwords can be a tough challenge for most people. What you need is some sort of portable, automatic, press-the-button-and-read-the-password device. Pass Key is an attempt at satisfying this requirement.

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Build It: A Smart, Ambient LED

Paired with a sensor, your "mood cube" can change color based on any number of outside stimuli

Ambient technology is the current rage for presenting information in a unobtrusive and, sometimes, sublime manner. Information suited for an ambient format ranges from complex number-laden data streams to simple one- or two-digit numbers. The idea here is that you can glean the same information by simply looking at the color of a cube, rather than consulting a sensor's text output.

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The Cordless Question

Too little power won't get the job done, too much is a waste of money. So how many volts do you need? To find out, just answer one question (truthfully): How handy am I?

The Golden Rule

Stick with one manufacturer, and you can use the same battery in all your tools-as long as they have the same voltage. So don't go for a 9.6-volt drill if you think you'll want an 18-volt reciprocating saw later. The descriptions below will help you determine how handy you really are around the house-and, thus, your future cordless tool needs.

The Unhandy Handyman

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