A 7-Segment Clock Built With No Digital Electronics

If you wanted to build a clock with a 7-segment display, there are many ways you might go about it. You could grab some 74-series logic chips …. A 7-Segment Clock Built With No Digital Electronics.

You could grab some 74-series logic chips and create a whole bunch of counters and decoders to drive the display, or you could wire up a microcontroller with an RTC and have it do the hard work. Or, as a Japanese company once did… you could create a “digital” looking clock with no digital electronics whatsoever. The geared mechanism and switch contacts are visible; they switch the neons of the various segments on and off at the correct times.

From the outside, it appears to be a rather stylish digital clock, with a bold red 7-segment display lit with neons. Only, the secret of this clock is that it doesn’t use digital electronics to do the job. There are no counters inside, no real-time clock module, no transistor-based logic chips doing the counting with the output of a 32.768 KHz crystal.

Instead, a motor drives a series of gears that turn metal plates that move under sliding finger contacts.