Cold War Clock Is All Tubes

A clock built from tubes


Clocks are great projects to build. They serve a real purpose, and there’s a wide variety of ways to implement a unique timepiece. [Hank]’s Cold War Clock only uses parts and technologies that were available in 1959. It contains no semiconductors, but has an audible alarm and reasonable time accuracy.

Looking through the hand drafted schematics, you’ll find a number of Dekatron tubes. These vintage components are used as registers to store and count the time. [Hank] found some cheap Soviet Dekatrons, but had to machine his own sockets to connect them. These tubes do the counting, but the actual display consists of nixies.

A cost estimate puts this clock at $2130 in 1959, which equates to $17040 today. Clearly this would be outside the price range of most hobbyists. The actual build cost [Hank] around $1600.

There’s some intricate details in this build. The front panel has an authentic look to it, and the manual has instructions for “demolition of clock to prevent enemy use.” [Hank] calls it a “creative anachronism.” In a sense, it’s a reproduction of a product that never actually existed.

A video of this clock in action, including the Cold War era alarm, is after the break.

45 thoughts on “Cold War Clock Is All Tubes

  1. Pulls 40 watts according to his operation and service manual. I expected much more.
    “The use of cold cathode tubes wherever possible is a big part of why the power draw in this clock is low.”
    Only 7 of the 94 tubes are vacuum tubes.

  2. If anyone didn’t recognise it: the tune at the beginning is “The Lincolnshire Poacher”, the identifier of a numbers station broadcast from the British airbase at Akrotiri in Cyprus, presumably to spies in place in the Middle East. If you don’t know what a numbers station is, look on the Wikipedia.

    It reminds me of the equipment on the B-52 in “Dr Strangelove”. A beautiful piece of work, and I’m amazed it draws only forty watts.

  3. This is incredible! However I’m a little confused – is this a completely from-scratch design, or is it based on an original instrument? I can’t quite understand the existence of the “manual”, since it sounds like he has designed and built everything from scratch. Or has he made the manual as well to look like it’s been scanned from 1959!?

    1. Pretty damn sure it’s just made to look vintage. The font is ‘modern’ for one thing. If it was truly old, it would have been done on a typewriter. I like how he even added some smudge marks, and a coffee cup stain on one page!

      Minor thing with the above storyline though… aren’t resistors semiconductors? *cough*

          1. So…you took three attempts to get it right when typing “they are” would have yielded a correct result first time. I fail to understand why people write contractions when it is just as simple to write two words. I am perfectly happy writing complete sentences with fully-constructed building blocks, which results in less time proof reading or correcting and zero time trying to explain to people what any cryptic writing, or use of acronyms/mnemonics is all about.

  4. Without question, this is my favorite of all the Hackaday projects I’ve seen since subscribing. If I had to nitpick anything, it’s that the font used on the faked manual (which was awesome!!) is too modern. Engineering ‘typesetting’ at the time was often done on an IBM Executive typewriter. I have one and have used it to get that authentic old-time look on documents. The faked hole punches and water stains really sell it. And the destruction section is extra awesome!

  5. (Slow, reverent clap)

    This is amazing. Love the simulated coffee cup stain in the Manual!

    The detail in the theory of operation is stunning. The AND gate to detect 24:00 is interesting, too; it adds two voltages together, but neither is sufficient to trigger a trigger tube, both must be there, hence the AND function.

    Just a stunning piece of work.

  6. wow, just wow.

    if i owned one i would add one of those little neons (as power indicator) that have green (upconverting?) phosphers XD

    i used to have one and i miss it so bad :(

  7. An amazing piece of work. One very small nit: the designation CD624/GSQ-70 isn’t quite right. In the “Joint Army Navy Nomenclature” designation system used by the Army, Navy, and Air Force in 1959, “CD” indicates a cord and plug set. A more appropriate designator would be “I”, meaning “indicator”, specifically a voltmeter, ammeter, or clock. GSQ-70 IS accurate – the “G” indicates a ground-based or general-use system, the “S” means special or combination, and the “Q” also means special or combination. The use of the “S” and “Q” would only have been used where there is no other designator that applies. In this case, there really isn’t any other designation that would have applied!

  8. This is truly fully art and fully functional technology. This is amazing to me. I have accumulated much vintage military electronics from the era and his equipment and related manual ‘photocopy’ hit all the marks. It reminds me of the epic vintage toy story crafted by Randy Regier which included not only the finished retrotoys but also the backstory of how the toys were lost, and photos of them being “discovered” in vintage packaging… Keep in mind all of these pictures in the flickr set are an artful fabrication. This clock is just like that. The only clue to collectors that it is not a vintage piece is the fact that Soviet tubes and other parts are used on a timepiece apparently of American origin. I feel he could have successfully trolled many a museum with this piece just as easily as admitting it was his work of art.

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