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Water Leak Detector

Water Leak Detector

The average life expectancy of a hot water heater is about 10 years, so it’s not a question of if it will leak — it’s simply a matter of when. In my part of the country, homebuilders have been installing these tanks in the attic. This saves space, but also means that if you don’t […]

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Treasure Finder

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 objects. The beat frequency between […]

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Wearable Light Organ

Wearable Light Organ

This simple, wearable circuit uses an operational amplifier (or “op-amp”) chip to convert sound into light. An LM324 op-amp and a transistor boost input from a mini condenser microphone to light a series of LEDs. Watch it blink to the beat of your favorite music. Check out more Weekend Projects.

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