The base unit houses an Arduino board which polls the buttons to see which is pressed first. The LED on the appropriate buzzer box is illuminated so the players know who got in first. One special ...

the sensor will detect a drop in light intensity and subsequently activate the buzzer. The alarm only stops when you press the push button connected to the Arduino. For this setup, the program ...

It’s also a very handy thing to have when paragliding, which is why [mircemk] decided to build a hand-held version using the Arduino Nano ... sensor, buzzer, and the 9 V battery that powers ...