CIS-4 Is A Monkish Clock Inside A Ceiling Lamp

July 4, 2025 by Tyler August No comments

It’s always clock time at Hackaday, and this time we have an interesting hack of a clock by [danjovic]– the CIS4, a Cistercian digital clock.

The Cistertians, in case you weren’t paying close attention to European holy orders during the 13th to 15th centuries were the group of monks you’d most likely have found us in. They were the hackers of the middle ages, establishing monestaries across western Europe that were chock full of hacks– including their own numeral system. Cistercian numerals were much more efficient (in spaces and penstrokes) than the Roman numerals they replaced, and even the “Arabic” numerals that replaced them. A single glyph could record anything from 1 to 9,999. (The Europeans hadn’t yet cottoned on to zero.)

The Cistertian glyphs reduced to a 4×4 display.

Depending how you wanted to count time, a single glyph could be used; it looks like [danjovic] is using the thousands and hundreds portions of the glyph for hours and the tens and ones for minutes. This is all accomplished with a 4×4 neopixel matrix, run by an Attiny85 Digispark with a DS3231 RTC module keeping time. A slight simplification is required to reduce the glyphs to 4×4, but we don’t think the monks would mind. For those of us who don’t wear tonsures, an easy read mode scrolls the time in Arabic numerals. (Which still aren’t super easy,with only 4×4 LEDs to display them. See the demo video embedded below and try and guess the time.)

One nice quality of life feature is an LDR for ambient light detection, to automatically adjust the neopixels’ brightness. The hackiest part, which we thought was really clever, is the enclosure: it’s a cheap LED ceiling light. This provides a diffuser, housing and mounting hardware with decent design for no effort. A 3D-printed mask sits between the diffuser and the LEDs and doubles as a PCB holder. All very elegant.

[danjovic] did include a buzzer in the design, but does say if its been programed to sound off for matins, nones and vespers. In any case, at least it’s easier to read than his binary-coded-octal clock that we featured a few years back. This isn’t our first look at this number system,so evidently people can read them with practice.

Have you made or seen a cool clock? Send us a tip. We always have time for clocks. Continue reading “CIS-4 Is A Monkish Clock Inside A Ceiling Lamp” →

2025 One Hertz Challenge: Electromechanical CMOS Clock Keeps In Step With Mains Frequency

July 4, 2025 by Tyler August 7 Comments

Some people can’t be bothered to read the analog face of a traditional clock. Some people cannot stand the low frequency “hum” of mains current. If you are in either of those categories, you probably don’t want to make [Christian]’s handsome and well-documented electromechanical CMOS clock.

As you might guess from the name, the clock uses CMOS logic, based around a 12 bit counter, to provide the divider circuits 24 (daily) and 60 (minutes and seconds). Specifically, the circuits are based around a CD4040 twelve-bit adder. Those signals go through DAC circuits based around DAC0808 chips to drive some very nice coil meters for hours and minutes in lieu of the traditional clock face. Taking the time to make a CMOS clock circuit from adder chips is respectable enough in this era of instant-gratification through micro-controllers, and we dig the blinkenlights built into the circuits, but it’s what is being added that is where things get really interesting.

[Christian] had the bright idea that a stepper motor could be driven via the mains, simply by using a capacitor to offset the waveforms on the coils by 90 degrees. With a 200-step stepper motor, [Christian] gets one revolution per second out of the 50 Hz grid; this generates the seconds signal for his CMOS chips by the simple expedient of a 3D printed arm and a light barrier. Once per second, the light is interrupted by the spinning arm, creating a pulse for the clock circuits to add up. Check it out in action in the demo video below.

This project also seems to have the distinction of being the first project submitted to our One Hertz Challenge. It’s not just for clocks, but keep an eye on your clock because entries are only open until 9:00 AM Pacific time on August 19th.

Continue reading “2025 One Hertz Challenge: Electromechanical CMOS Clock Keeps In Step With Mains Frequency” →

This Thermochromic Clock Is A Ray Of Sunshine

June 16, 2025 by Tyler August 5 Comments

It’s never a bad time to look at a clock, and one could certainly do worse than this delightful Paper Sunshine Clock by [anneosaur]. The sun-ray display is an interesting take on the analog clock, and its method of operation is not one we see every day, either.

Reading the clock is straightforward: there are twelve rays divided into two segments. Once you figure out that this artful object is a clock, it’s easy enough to guess that the rays give the hours, and half-rays are half-hours. In the photo above, it’s sometime between nine o’clock and nine thirty. Our Swiss readers might not be terribly impressed, but a “fuzzy” clock like this is quite good enough much of the time for many people.

Even the flex PCB holding the resistors looks like a work of art.

The title gives away its method of operation: it’s thermochromic paint! The paint is printed onto a piece of Japanese awagami paper, which is pressed against a flexible PCB holding an array of resistors. Large copper pads act as heat spreaders for the resistors. For timekeeping and control, an Atmega328PB is paired with a DS3231MZ RTC, with a coin cell for backup power when the unit is unplugged. (When plugged in, the unit uses USB-C, as all things should.) That’s probably overkill for a +/-30 minute display, but we’re not complaining.

The Atmega328PB does not have quite enough outputs to drive all those resistors, so a multiplexing circuit is used to let the 10 available GIPO control current to 24 rays. Everything is fused for safety, and [anneosaur] even includes a temperature sensor on the control board. The resistors are driven by a temperature-compensated PWM signal to keep them from overheating or warming up too slowly, regardless of room temperature. The attention to detail here is as impressive as the aesthetics.

[annenosaur] has even thought of those poor people for whom such a fuzzy clock would never do (be they Swiss or otherwise) — the Paper Sunshine Clock has a lovely “sparkle mode” that turns the rays on and off at random, turning the clock into an art piece. A demo video of that is below. If you find this clock to be a ray of sunshine, everything you need to reproduce it is on GitHub under an MIT or CC4.0 license.

This is not the first thermochromic clock we’ve featured, though the last one was numeric. If you must have minute accuracy in a thermochromic analog clock, we’ve got you covered there, too.

Special thanks to [anneosaur] for submitting the hack. If you’ve seen (or made) a neat clock, let us know! You won’t catch us at a bad time; it’s always clock time at Hackaday.

A clock face is shown consisting of two rings of plastic, with backlighting behind one of the rings. There is red light at the one o’clock position, and blue light at the nine-thirty position. A black plastic arm is pointing to the three-thirty position.

A Concentric Clock With Multiple Modes

June 14, 2025 by Aaron Beckendorf No comments

Most of us spend our lives within reach of a device that provides a clock, stopwatch, and a timer – you’re almost certainly reading this article on such a device – but there are fewer options if you want a screen-free clock. [Michael Suguitan]’s TOKIDOKI rectifies this situation by combining those three functions into a single, physical, analog clock face.

TOKIDOKI displays time by lighting the appropriate segments of two concentric rings of colored LEDs (Adafruit Neopixel rings); the inner ring indicates hours, while the outer ring displays minutes. There is one clock hand, and while it does indicate the passage of time in some situations, its main function is as a dial to control the clock’s different functions. The hand is connected to a Dynamixel XL-330 servo motor, which also serves as a position sensor. Winding the dial clockwise starts a countdown timer, with each successive full rotation switching to a larger unit of time (a fun/unsettling feature is that the largest chronometric unit is the user’s expected lifetime: 84 years). Winding counterclockwise either starts a stopwatch or sets an alarm, depending on how many full rotations you make.

A Raspberry Pi Pico running some MicroPython firmware manages the device and gets the current time from a local network. To soften the light’s quality, the LED rings are pointed backwards to provide back-lighting off of a recessed surface. The entire device is powered by USB-C, and is enclosed in a 3D-printed housing.

This project was designed as an experiment in minimal interfaces, and it certainly achieved that goal, though we imagine that it takes a bit of time to get used to using this clock. We always enjoy seeing innovative clocks here, from digital to analogue, and those that split the difference. Continue reading “A Concentric Clock With Multiple Modes” →

A Close Look At The Mitxela Precision Clock Mk IV

June 8, 2025 by John Elliot V 15 Comments

Over on his secondary YouTube channel, [Jeff Geerling] recently demoed the new Mitxela Precision Clock Mk IV.

This clock uses GPS to get the current time, but also your location so it can figure out what time zone you’re in and which daylight savings time might apply. On the back a blinking diode announces the arrival of each second. A temperature-compensated crystal oscillator (TCXO) is employed for accurate time-keeping.

The clock can be folded in half, thereby doubling as a clapperboard for movie makers. The dimming system is analog, not pulse width modulation (PWM), which means no visible flashing artifacts when recording. It is highly configurable and has USB connectivity. And it has not one but two ARM microcontrollers, an ARM STM32L476, and an ARM STM32L010. If you’re interested, you can pick one up for yourself from [Mitxela]’s shop.

Toward the end of his video [Jeff] does some navel gazing, thinking about what might be required if future versions of the clock wanted to get down into precision at the nanosecond level. Do you arrange it so the light arrives at the viewer’s eyeball at the right time? Or do you update it on the clock at the right time and let the viewer know about it after a minuscule delay? Philosophical preponderances for another day!

We should add that we’ve seen plenty of cool stuff from [Mitxela] before, including the Euroknob and these soldering tweezers.

Continue reading “A Close Look At The Mitxela Precision Clock Mk IV” →

A woman in a richly-colored blue head scarf leans over a wooden table looking at the timer between her hands. The timer has a yellow circle on black flip panels on the left and black and white CT scans of a human torso on the right side. The frame is wood, and there is an electric motor on the upper right of the frame and a silver drum on the left of the frame beneath the woman's hand.

A Flip Clock Becomes A Flip Timer

June 6, 2025 by Navarre Bartz 2 Comments

Sometimes it’s nice to have a widget to do a single task and avoid getting distracted by the supposed simplicity of doing it with an app on a smartphone. [Dina Amin] built a timer from an old flip clock to stay focused.

Starting with a disassembly of the flip clocks she found at a flea market with [Simone Giertz], [Amin] decided to change the twenty four hour mechanism to a twenty four minute one which was similar to the amount of time she was already using for several different practices. Since she’s an expert in animation, she planned on turning a set of CT scans into the animation that would play on the section that had previously been the minutes of the clock.

As much of the original clock’s components were damaged, and [Amin] didn’t have a chance to learn clockmaking from scratch in a week, she tried a few different drive mechanisms for the build. The drum from an air fryer timer driven with an electric motor fit the bill, but off enough from proper minutes that [Amin] switched from numerals to a yellow circle that fills in as it approaches the satisfying ding of completion.

If you want to see Simone’s Moon flip clock we’ve covered that project too.

Continue reading “A Flip Clock Becomes A Flip Timer” →

Open Source Watch Movement Really Ticks All The Boxes

June 3, 2025 by Tyler August 32 Comments

When you think of open-source hardware, you probably think of electronics and maker tools– RepRap, Arduino, Adafruit, et cetera. Yet open source is an ethos and license, and is in no way limited to electronics. The openmovement foundation is a case in point– a watch case, to be specific. The “movement” in Openmovement is a fully open-source and fully mechanical watch movement.

Openmovement has already released STEP files of OM10 the first movement developed by the group. (You do need to sign up to download, however.) They say the design is meant to be highly serviceable and modular, with a robust construction suited for schools and new watchmakers. The movement uses a “Swiss pallets escapement” that runs at 3.5 Hz / 25,200 vph. (We think that’s an odd translation of lever escapement, but if you’re a watchmaker let us know in the comments.) An OM20 is apparently in the works, as well, but it looks like only OM10 has been built from what we can see.

If you don’t have the equipment to finely machine brass from the STEP files, Openmovement is running a crowdfunding campaign to produce kits of the OM10, which you can still get in on until the seventh of June.

If you’re wondering what it takes to make a mechanical watch from scratch, we covered that last year. Spoiler: it doesn’t look easy. Just assembling the tiny parts of an OM10 kit would seem daunting to most of us. That might be why most of the watches we’ve covered over the years weren’t mechanical, but at least they tend to be open source, too.