Four old rotary telephones become a reflex game. One rings at random, and the player must pick up the correct handset within one second. Answer the wrong phone or miss the deadline and the game is over.

The Tōhō Electronics Club built the game, called 'Nostalgic Rotary Phone Whack-a-Mole.' An Arduino and relays choose which phone rings. The team also built circuitry to generate the 75 V, 16 Hz signal needed to ring the bells and detects when a handset is lifted through a change in resistance.