Ian Dunn's Decade Logic Clock Is a Kit Aimed at Demystifying Surface-Mount Soldering — and Time

Maker and power grid operator Ian Dunn, of Bolt Industries, has launched a crowdfunding campaign for a clock with a difference, powered by the Texas Instruments CD4017 decade counter — and is making it available as a soldering kit.

"The [TI] CD4017 is a really neat decade counter chip," Dunn explains of his reason for picking the part to power the clock. "It counts incoming pulses from zero to ten and resets to zero. By stacking 6 of them and adding a 1Hz square wave input, they make a perfect clock! The 1Hz time source is generated from a 32.768khz quartz crystal oscillator, two 24pF capacitors and three resistors, just like your old digital wrist watch from before the days of smart watches."

Dunn should know: this is his second time using the chips for a clock, having successfully run a crowdfunding campaign in 2021 for a very similar design. This time, though, the through-hole technology (THT) parts of the original kit have been ditched for surface-mount technology (SMT) equivalents for a sleeker design — but that, Dunn says, shouldn't put newcomers to SMT soldering off assembling the kit.

"Many people have an aversion to surface mount components because they are so small. For this design, larger surface mount components were intentionally selected," Dunn says. "If this will be your first attempt at surface mount soldering, you'll probably find that it's a nice change to not have to trim the component leads."

The CD4017 Digital Logic Clock 2.0 is currently funding on Kickstarter, having already reached its goal; the kit is available at $20, including the PCB and components but excluding a USB Type-C cable and power supply to get it up and running post-assembly.