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Geiger Counter

Geiger Counter

This DIY Geiger counter clicks and flashes an LED each time it detects a radioactive particle. It works with most common Geigerโ€“Mรผller tubes, and easily connects to radiation rate meters, data loggers, true random number generators, and the Radiation Networkโ€™s GeigerGraph software. Share your radiation readings with the whole world!

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.