Talk about your mixed timekeeping metaphors: there are clocks, and pendulum clocks, and there are Nixie clocks, and persistence of vision clocks. But this is a Nixie pendulum POV clock, and we think it’s pretty cool.
We first spied this on Twitter and were subsequently pleased to learn that [Jayzon Oeve] has posted a more detailed build log over on Hackaday.io. Rather than a moving array of dots to create the characters to display, this uses a single IN-12b Nixie tube at the end of a pendulum. The pendulum is kept moving by a small nudge created by a pulse through a fixed hard drive voice coil acting on a magnet affixed to the bottom of the pendulum — we’ve seen a similar approach used before.
Pretty much all of the electronics are mounted on the pendulum arm, including a Nano, an RTC, and an accelerometer to figure out where in the swing the bob is and when to flash a number on the display. There’s a video below that shows it at work both at full speed and in slow-motion; as always with POV clocks, these things probably look better in person than on video. And while swinging Nixies around like that seems a little dicey, we like the way this turned out.
With little more than four economical stepper motors, a Raspberry Pi Zero, and a 3D printer, [Thomas Barlow] made himself an awfully slick Smart Flip Clock that can display not only the time, but also weather data as well. This is done by adding a few extra graphics to some of the split-flaps, so numbers can also be used to indicate temperature and weather conditions succinctly. Displaying the time has to do without a colon (so 5:18 displays as 518), but being able to show temperature and weather conditions more than makes up for it.
32 degrees and a mix of sun and cloud
According to the project’s GitHub repository, it looks as though each split-flap has thirteen unique positions. The first ten are for numerals 0 through 9, and the rest are either blank, or used to make up a few different weather icons with different combinations. A Python script runs on the Raspberry Pi and retrieves weather data from OpenWeather, and the GPIO header drives the display via four geared stepper motors and driver boards. The rest of the hardware is 3D printed, and [Thomas] helpfully provides CAD models in STEP format alongside the STL files.
The early Cold War years may have been suffused with existential dread thanks to the never-ending threat of nuclear obliteration, but at least it did have a great look. Think cars with a ton of chrome, sheet steel toys with razor-sharp edges, and pretty much the entire look of the Fallout franchise. And now you can add in this boat anchor of an electromechanical Nixie clock, too.
If [Teti]’s project looks familiar, perhaps it’s because the build was meant as an homage to the test equipment of yore, particularly some of the sturdier offerings from Hewlett-Packard. But this isn’t some thrift store find that has been repurposed; rather, the entire thing, from the electronics to the enclosure, is scratch built. The clock circuit is based on 4000-series CMOS chips and the display uses six IN-1 Nixies. Instead of transistors to drive the tubes, [Teti] chose to use relays, which in the video below prove to be satisfyingly clicky and relaxing. Not relaxing in any way is the obnoxious alarm, which would be enough to rouse a mission control officer dozing in his bunker. [Teti] has a blog with more details on the build, the gem of which is information on how he had the front panel so beautifully made.
We can’t say enough about the fit and finish of this one, as well as the functionality. What’s even more impressive is that this was reportedly [Teti]’s first project like this. It really puts us in mind of some of the great 6502 retrocomputer builds we’ve been seeing lately.
There’s a document I had to sign to wrap up a community responsibility in rural Oxfordshire. At the bottom, dotted lines for signature and date. My usual illegible scrawl for a signature, and scribble in the date below it. Then there’s the moment when the lady handling the form scans it with a puzzled face for a minute, before accepting it with a smile. She’s just been ISO’d!
I’m telling you, you’ve got Pi Day wrong. Evan Shelhamer, CC BY 2.0.
Where I come from in England, it’s the norm to represent dates in ascending order: day, month, year. Thus the 4th of March 2021 becomes 04/03/2021 when written down on a form. This is entirely logical, and makes complete sense given the way a date is said aloud in English and other languages.
Meanwhile in America it’s the norm to represent dates in a different manner: month, day, year. Thus March 4th, 2021 becomes 03/04/2021 when written down on a form. This is also entirely logical, and makes complete sense given the way dates are pronounced in American English.
As someone whose job entails crossing the Atlantic in linguistic terms, I am frequently confused and caught out by this amusing quirk of being divided by a common language. Is 03/04/2021 the 3rd of April or March 4th? “Why can’t Americans use a logical date format!” I cry as in a distant transatlantic echo I hear my friends over there bemoaning our annoying European ways. It’s doubtful that this divergence has caused any satellites to crash, but it sure can be annoying.
Confusing Everyone For Over Three Decades
So I took a stand. A couple of decades ago I adopted ISO 8601 in writing dates, an international standard that’s been with us for well over three decades. It too is an entirely logical way to express time, but unlike the two mentioned earlier it’s not tied to any linguistic quirks. Instead it starts with the largest unit and expresses a date or time in descending order, and extends beyond dates into time. Thus the date on my form that caused the puzzlement was 2021-03-04. I’m guessing that here at Hackaday I’m preaching to the choir as I certainly won’t be the only one here using ISO 8601 in my daily life, but while we’re talking about alternative date formats within our community it’s an opportunity to take stock of the situation.
UNIX time is probably the most instantly recognisable of all our measurement schemes, being a count of seconds elapsed since the Unix epoch of 1970-01-01T00:00:00+00:00 UTC. Coincidentally this is also an auspicious date for many readers, as it’s our birthday. If I’d written the 4th of March on that form as 1614816000 though I would have been met with complete incomprehension, so aside from the occasional moment of coming together to observe a rollover it’s not something we use outside coding.
But it does lead neatly to another question: since UNIX time is most often expressed in text as a base-10 number, why on earth does our clock time work in base 60 for seconds, base 12 or 24 for hours, and then base 12 for months? Why don’t we use a base 10 metric time system?
It makes sense for our annual calendar and the length of our day to be derived from Earth’s orbit, as we use dates as a measure of season and times as a measure of the daily progress rather than simply elapsed periods. We owe our twelve-hour days and nights to the ancient Greeks and our 60 seconds and minutes to the ancient Babylonians, while our twelve months come from the ancient Romans. It’s clear that a 365.24-day year with four seasons doesn’t divide neatly into ten months, so we’re at the mercy of our own set of celestial bodies when talking about dates. But surely we could move on from ancient Greece and Babylon when it comes to the time of day?
Liberté, Égalité, Ponctualité!
A 10-digit Revolutionary French clock. DeFacto, CC BY-SA 4.0
Probably the most famous attempt at a decimal calendar came in the aftermath of the French Revolution; the French Republican calendar perhaps wisely stuck with twelve months but made each of them of three 10-day weeks, and then split the day by 10 hours, with each further subdivision being by base 10. The months each had 30 days, with the remaining 5 days (or 6 in leap years) being public holidays.
It came to an official end when the revolutionary government that had introduced it was replaced by that of Napoleon. Unlike other French Republican measurements such as the meter, it evidently didn’t provide enough advantage for its popularity to outlive its political origins.
There’s an interesting parallel in the decimalisation of British currency in 1971. Previously, a pound was 20 shillings, each of which were 12 pence. Afterwards, a pound became 100 new pence, and that’s stuck. Despite some people’s lingering nostalgia for the old system, the utility of decimialisation was self-evident.
The moral of the French time-decimalization story was that people simply use a calendar and time system to tell the date and time. When you need to do frequent arithmetic, as is the case with currency, distance, or weights, this is made significantly easier through decimals. But when nature hands you four seasons, you’re pressed into twelve months. Perhaps when we slip the bonds of Earth, we’ll use decimal Stardates, but in the mean-time, ISO might just be the way to go.
Over on [Techmoan]’s YouTube channel he’s excited about a new gadget that finally arrived after months of waiting — the EleksTube IPS fake Nixie tube clock. This is a re-imagining of a Nixie tube clock using six 135×240 pixel IPS display panels. They are mounted like tiny billboards, each one inside glass bulbs to mimic that retro look. Based on [Techmoan]’s measurement of these displays, it appears they are the same 16:9 IPS displays used in the TTGO ESP32 modules. The effect is quite impressive, and the fact that each digit is a complete display leads to quite a bit of flexibility. For example, if you don’t like the Nixie look, you can select from a suite of styles or make your own set of custom digits.
By this point, pretty much everyone has come across a word clock project, if not built one themselves. There’s just an appeal to looking at a clock and seeing the time in a more human form than mere digits on a face. But there are senses beyond sight. Have you ever heard a word clock? Have you ever felt a word clock? These are questions to which Hackaday’s own [Moritz Sivers] can now answer yes, because he’s gone through the extreme learning process involved in designing and building a haptic word clock driven with the power of magnets.
Individual letters of the display are actuated by a matrix of magnetic coils on custom PCBs. These work in a vaguely similar fashion to LED matrices, except they generate magnetic fields that can push or pull on a magnet instead of generating light. As such, there are a variety of different challenges to be tackled: from coil design, to driving the increased power consumption, to even considering how coils interact with their neighbors. Inspired by research on other haptic displays, [Moritz] used ferrous foil to make the magnets latch into place. This way, each letter will stay in its forward or back position without powering the coil to hold it there. Plus the letter remains more stable while nearby coils are activated.
Check out the video below to see this display’s actuation in action. We’re absolutely in love with the satisfying *click* the magnets make as they latch into place.
We were beginning to think we’d seen it all when it comes to RGB clocks, but [andrei.erdei] found a fast path back into our hearts and minds. This clock is a digital representation of an ancient numeral system used by 13th century Cistercian monks before the Indo-Arabic system that we know and love today took over. It’s a compact system (at least for numbers 1-9,999) that produces numerals which sort of look like 16-segment displays gone crazy.
Every numeral has a line down the middle, and the system uses the four quadrants of space around it to display the ones, tens, hundreds, and thousands positions starting in the upper right corner.
[andrei] adapted the system to show time by assigning tens of hours to the thousands quadrant in the bottom left, hours to the hundreds quadrant in the bottom right, tens of minutes in the upper left, and minutes in the top right. The tricky part is that the system has no zero, but [andrei] just darkens the appropriate quadrant to represent zero.
The timekeeping is done with an ESP-01, and there are a total of 31 RGB LEDs including the middle bit, which blinks like a proper digital clock and doubles as a second hand. As usual, [andrei] has provided everything you’d need to build one of these for yourself. We admit that the system would take a little time to learn, but even if you never bothered to learn, this would make a nice conversation piece or focal point for sitting and staring. Take a minute to check it out in action after the break.
