Free Range Technology

Nuclear Repurposing

When you name your blog after a kitchen appliance powered by nuclear fission, you will occasionally get strange things on the tip line (which is tips at atomictoasters dot com if you have any strange things to tip us on). Most of them are quickly discarded before CardboardTube’s virgin eyes are defiled by the unsavoriness of the suggestion.

Others linger until one of us finally gets off our ass and does something with it.

That is the story behind today’s post. You see, a while back reader bzr sent in this fantastic project from Instructables: take a 1950s era bakelite slave dial and turn it into an atomic-fed superclock! Hell, we’re on a repurposing kick today, so why not?

Slave dials were mechanical clocks without the clock mechanism. A central timekeeper would drive the slave dial hands through electrical pulses. They were used in train stations and large office buildings to make sure all the clocks read the same time. That is, unless someone took the clock down and moved the hands. Not that I’ve ever done that, but I knew a guy…

This project uses a slave dial, an Arduino board with WiFi, and various resistors, capacitors and a power supply to drive the slave dial based on an internet time signal synchronized to the NIST atomic clock in Colorado.

So, who will be the first to do this? You can find the instructions here!

[Image Credit:]

  • Alff

    Hadn't thought about slave clocks in years – we had them in elementary school.

    • mr. mzs zsm msz esq

      I even had them in HS but something more advanced I think. They was a way to sync them all up and when this happened you saw the hands move.

      • Every once in a while they would all start going 3x as fast until each one synched properly. And of course some kid would try to claim that class was over when it obviously wasn't.

  • P161911

    I remember slave clocks were one of the many high tech (for late 1800s) features at the Biltmore House.

    • OA5599

      Couldn't be. The house was built after the ratification of the 13th Amendment.

  • Mr_Biggles

    I spent a few seasons working on a ship doing adventure tourism to and from Antarctica. All the wall clocks on the ship were slave clocks. They seemed to have some rule or other for when to change them and when not to, because they didn't do it for every time zone. But it always felt a bit odd watching them spin up by an hour every so often.

  • Charles_Barrett

    Professor Thomas Apostle taught Freshman Calculus for many years at Caltech. In fact, he wrote the book (and sold all three volumes to us over the course of the year). Being a Freshman requisite, it was one of the largest lectures on campus, in a room with triple-stacked power chalkboards, three banks wide. and a synchronized clock on the wall.

    Prof. Apostle had his lectures well documented and annotated for his use. One year, some students altered the clock in the lecture hall to run gradually faster, over the span of a few days, so that he found himself having to step up the pace of the lecture gradually but increasingly as the week progressed (it always reset to proper time for the start of the next lecture), in order to cover the material he knew he needed to based on his notes from years past.

    Another prank took remote control of his chalkboard positioning switches, so that when he needed a fresh board, one zoomed down just in time. He soon caught on, and when he needed to refer to a previous board, he merely gestured broadly, and the chalkboard in question came as beckoned.

    Ah, undergraduate life at Caltech…

    • Alff

      Caltech 38, MIT 9

    • I love your Caltech stories.

  • discontinuuity

    Hey, I just drove past the NIST building in Boulder a few days ago. I like to think that the atomic clock in my house is that much more accurate because it's only 20 miles from the transmitter.

    While in Boulder my brother and I decided to count all the Subarus and Toyota Priora that we saw. I was up to about 15 Subarus in about as many minutes, while my brother had about 12 Priora.