They’re using a cheap sound sensor module and an Arduino to catch instantaneous photographs, with students caught in the act of popping balloons.

The microphone sound sensor – Grove Sound Sensor (v1.6) – is built around the popular dual-op amp IC LM358 and provides an analog signal output. The recommended operating voltage is 5V what makes it ...

Power-wise, these warmers use a 18650 cell and a TP4056 charging module. Everything is controlled by an Arduino Nano, which reads from both a thermistor and a potentiometer to control the output.