A 1Hz Clock from Three Candles: Reversing Millennia of Optimization
2025-08-19
For millennia, candlemakers have strived for flicker-free candles. However, when three candles are bundled together, they surprisingly begin to oscillate naturally at ~9.9Hz, a frequency primarily determined by gravity and flame diameter. The author ingeniously uses a wire suspended in the flame to sense capacitance changes caused by ionized gases, detecting this frequency and dividing it down to 1Hz. The result? A 1Hz clock built with a simple microcontroller and an LED, powered by the flickering of three candles.
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Hardware
Sensors