Perhaps you remember an “As Seen on TV” product known as “The Clapper” in the 1980s and 1990s. The TV commercials could be seen on almost every channel. The premise was simple: a 120 VAC relay would control power to appliances and respond to two sharp noises, specifically two claps. We’re going to make our own version of this, but instead of controlling any appliance, we will operate a lamp chain using a servo.”

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