[Larry] solved his trivia game buzzer problems by building a wireless buzzer set. It features 3D printed enclosures containing Adafruit Feather microcontrollers, and instead of wires it uses ...

There are several other quiz buzzer projects kicking around Hackaday if you’re interested. One of our favorites is this system which uses plastic bowls as the buttons.

Door buzzer entry systems are no longer as archaic as simple noise to alert people. They have grown complex but remain simple ...