Like most flip clocks from the 60s and 70s, the Copal clock uses a small synchronous AC motor to advance the digits. Because this motor runs in step with the mains frequency, it also acts as the ...

You can buy pared down, exposed flip clocks at museums for an arm and a leg, or you can trudge through eBay and local thrift shops until you come across a cheapo clock radio. [Super Cameraman’s ...