clock hacks

1030 Articles

A man's arm is shown against a mountainous backdrop. The man is wearing a black watch with an orange segment on one side.

Restoring An Altimeter Watch To Former Heights

October 10, 2026 by No comments

Finding inexpensive broken hardware for sale, buying it, and restoring it to working condition is a long-standing tradition for hackers on a limited budge. But there are some devices that are so difficult to repair that it’s usually not worth the trouble. [Vintage560] is braver than most, though, and restored an internally-damaged Casio AW-330-AT altimeter watch.

The exterior of the watch was in good condition, other than missing a readily-replaced strap, but the battery had leaked into the interior, and the watch didn’t respond in any way to new batteries. Cleaning out the guts with isopropyl alcohol, repositioning a plastic insulator, and bending some contacts back into shape at least got some segments of the LCD display to activate, while over two days of turning the crown smoothed out resistance in the analog train.

Actually getting the LCD to work properly required disassembling the watch, taking particular care with the altitude sensor. It wasn’t clear what was wrong with the LCD — the controller seemed to be working properly, and several rounds of cleaning and adjusting the ZEBRA connector didn’t make any difference.

Eventually, [Vintage560] simply purchased a new screen. On close inspection, it looked as though chemicals from the leaking battery might have dissolved some of the transparent indium tin oxide contacts on the old display. With the watch now working [Vintage560] tested it on a trip to the Alps, and with a few periodic calibrations, it remained quite accurate.

Usually when we see Casio watch hacks, the watch in question is the F91W, whether it’s being used for contactless payments, being retrofitted as a smartwatch, or going 5,000 meters underwater.

A 7-Segment Clock Built With No Digital Electronics

September 24, 2026 by 29 Comments

If you wanted to build a clock with a 7-segment display, there are a wide variety of ways you might go about it. You could grab some 74-series logic chips and create a whole bunch of counters and decoders to drive the display, or you could wire up a microcontroller with an RTC and have it do the hard work. Or, as a Japanese company once did… you could create a “digital” looking clock with no digital electronics whatsoever.

The geared mechanism and switch contacts are visible; they switch the neons of the various segments on and off at the correct times. Credit: YouTube video

[Mark Furneaux] set about tearing down a Lumitime clock, built by the Japanese company Tamura. From the outside, it appears to be a rather stylish digital clock, with a bold red 7-segment display lit with neons. And in some regards, it is. Only, the secret of this clock is that it doesn’t use digital electronics to do the job. There are no counters inside, no real-time clock module, no transistor-based logic chips doing the counting with the output of a 32.768 KHz crystal. Instead, a motor drives a series of gears that turn metal plates that move under sliding finger contacts. The gear train and the metal plates are designed such that the contacts turn the various segment neons on in the correct sequence to display the current time. It’s like a player piano, only instead of playing a tune, it’s switching the segments of a display on and off to display the right numerals at the right time.

It’s a neat way to do a “digital” clock from an era when proper digital electronics were still very expensive. We’ve seen all kinds of whacky 7-segment clocks before, too, like this amusing water-based build. Video after the break.

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Printing A Clock Fit For A Pope

September 17, 2026 by 12 Comments

When it comes to clockwork, there is a spectrum — some people love the ticking, and some people hate it, while most fall into the broad middle of indifference. Once upon a time, Pope Alexander VII fell into the “hate it” category, and commissioned a silent timepiece from [Fratelli Campani] in 1656. Three hundred seventy years later, [Many Vices] sought out to re-create the mechanism in extruded plastic thanks to the efforts of watchmaker [Carlo G. Croce], who documented his brass recreation in this PDF file and his own videos.

While the archaeology of recreating the mechanism from old photos is interesting, the mechanism itself is the real showpiece. The secret, as you might be able to tell from the photographs, is an eccentric crank escapement that provides continuous movement rather than the traditional anchor escapement whose periodic movements creates the distinctive ‘tick’ and ‘tock’. [Many] tests both in his video so you can hear the difference and see how much power is wasted with the crank escapement, which doesn’t keep going very long.

We wonder if carefully tuning the flywheel he’s using to match the frequency of the swinging pendulum would help a little there. Likewise, his linear-rail-based spring pendulum modification — though it does look awesome and we’d love a train-themed clock using it — doesn’t come close to providing the runtime of traditional clockwork. That’s probably why the anchor escapement persisted for centuries, even if some people and Popes couldn’t stand the tick-tock.

We’ve featured a lot of different 3D printed clocks, from wholly mechanical to electromechanical digital units to even ones based on D20s , so it’s hard to believe that not much more than a decade back, printing a mechanical clock was considered a challenge. Time marches on whether we can hear it or not.

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A Super-Accurate Clock Using A Tiny Microcontroller

September 15, 2026 by 27 Comments

DCF77 is a German VLF transmitting station that broadcasts a time signal across Europe on 77.5 kHz. Thus a common sight in a European home is a clock emblazoned with the words “Radio controlled”. With the timing broadcast in a simple and low speed digital format it doesn’t require the greatest of hardware to decode, and a small microcontroller can handle the task with ease. And there are few smaller than an ATtiny as used in [kwolf1909]’s decoder. It takes a DCF77 bitstream from a receiver, and shows the time on an I2C display.

The receiver isn’t part of this project, however a single-frequency longwave receiver is not a difficult thing to build. The interface is a push-button, for which a short press cycles between display modes and a long press triggers a DCF77 reset. It also supports an external temperature sensor and real time clock module, if you’re using an ATtiny with enough pins.

We like this project; it’s simple and does one thing well, and it’s a welcome reminder that not every device needs a powerhouse of a processor. If you’re interested enough to build your own, we’ve featured someone doing a deep dive into the signal before.

An angular, 3D-printed base holds two icosahedra with numerals on their faces. Each icosahedron has a zig-zagging path running through it, showing red gears inside.

Keeping Time On Tumbling Icosahedra

September 13, 2026 by 10 Comments

Clocks are almost the ideal devices to inspire creativity in hackers — they have a simple, well-defined task, but there’s an almost unlimited number of ways to carry it out. [ekaggrat singh kalsi]’s OVODYO is a particularly intriguing approach, tumbling a pair of icosahedral counters to display the current time.

Each 3D-printed icosahedron has numerals sunk through each of its twelve sides, and is raised above the base of the clock on a brass support shaft. An inner drive shaft runs through the center of the support shaft and drives a set of beveled gears. These spin the outer shells around two axes, periodically cycling through all twelve faces. The pattern in which an icosahedron rotates means that only set of numerals appears upright at a time, making it easier to distinguish the time.

A split path around the icosahedra both lets them rotate around the support shaft and shows off the internal gearing. On the control side, an ATmega8 drives a pair of stepper motors with drv8833 motor drivers, using a hall effect sensor to detect each indicator’s position. Since the minutes dial only gives the time in five-minute intervals, it also drives an LED strip to indicate the exact minute.

[ekaggrat] has a long history of creative clock designs, from this dynamic chain-link sculpture to a hair-tie clock or a mechanical seven-segment display.

Continue reading “Keeping Time On Tumbling Icosahedra” →

Big Infinity Mirror Clock Invites You To Gaze Deeply

September 12, 2026 by 10 Comments

[Andy Huot] has a fantastic-looking infinity mirror digital clock that really raises the bar. It uses high quality components, smart use of RGB LED animations, and a clever “stacked diffuser” vertical design to the 7-segment display elements that really enhances the infinity mirror effect. It needs to be seen in action, so check it out.

The end result is expressly portal-like, with the smooth animations of the LEDs really playing into the effect. The size helps, too. It’s 24 inches in diameter, giving it considerable presence.

The stacked diffuser design for each display element really enhances the effect.

A basic infinity mirror design consists of lit elements sandwiched between a reflective back surface and a partially-reflective, partially-transmissive top cover. That same basic principle is used here, but with great care given to ensure nothing so much as a fingerprint spoils the illusion. For example, the top cover is a disk of acrylic with a 90% reflective film affixed to the inside surface. That’s easy enough to DIY with some car tint, but [Andy] found that for the very best results it was worth having high-quality film professionally applied.

We like the use of 3D-printed custom jigs for soldering the segments of RGB LED strips, and holding the pre-measured wires in place with some putty is a great way to keep them in place while working. In case you’re wondering, the mirrored acrylic making up the back wall has holes in it for mounting each segment’s LED strip in a holder, and running the wires to the rear.

The video (embedded below) documents every step of the assembly, and it’s a serious build. While the design files for the 3D-printed parts are not free, there’s certainly enough detail for an enterprising hacker to replicate the design in their own way.

Continue reading “Big Infinity Mirror Clock Invites You To Gaze Deeply” →

ESP32-P4 Powers Video Alarm Clock

September 7, 2026 by 3 Comments

Once upon a time, you had the option of waking up to a bell, a harsh buzzer, or whatever happened to be on the radio that morning. Now that it’s the 21st century, we’ve gotten used to being able to set our alarms to whatever sound or song we want, but what if you don’t just want to wake up to sound? Enter [Impossible_Agent1436] a.k.a. [brunokeymolen]’s Video Alarm Clock that will wake you up to whatever clip you want, as long as it fits on the 720 pixel square display.

That display is a pre-built Waveshare module powered by an ESP32-P4, which looks like a handy bit of kit aside from being out of stock at the moment. The dev board makes this almost entirely a software project– the only hardware [bruno] had to come up with was the 3D-printed stand to hold it on his bedside. That’s not a slight to [bruno]; it was a good choice in the spirit of “work smarter, not harder”. Sometimes you want to reinvent the wheel, and sometimes you just want an alarm clock.

The module’s RTC means it keeps good time, and the built-in SD card reader means you can load up a whole library of clips to wake up to. The only caveat is that those files have to be AVI containers holding 720×720 MJPEG video with PCM stereo audio at 44.1 kHz, and you’re limited to old FAT filename rules: eight characters, and none of them special.

This is an easier project and a better idea than the exploding capacitor alarm clock, but there’s no arguing which would get us out of bed faster. If you miss the old days of clock radios, you can always bring them back with the right microcontroller.

Story via reddit.