LEDs are designed to emit light, but they also make surprisingly capable sensors. Using only an Arduino UNO, an LED and a resistor, we will build a hot LED anemometer that measures wind speed, and turns off the LED for 2 seconds when it detects you are blowing on it. You can use this to make breath controlled interfaces, or even an electronic candle that you can blow out!
Materials:
An Arduino UNO (with USB cable to connect to your computer)
A 1/4W 220 ohm resistor (https://www.amazon.com/Projects-25EP514220R-220-Re…)
A pre-wired, 0402 yellow LED (https://www.amazon.com/Lighthouse-LEDs-Angle-Pre-W…)
Breakaway header (https://www.amazon.com/SamIdea-15-Pack-Straight-Co…)
You will also need:
A computer to run the Arduino environment
Basic soldering equipment/skills”

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