If you wanted to make a rotating display box, what would you use to make it spin? A servo? A stepper motor? [ChrisN219] didn’t need his to move quickly by any means, and this opened up his options to something we probably wouldn’t have thought to use: a clock movement. Specifically, the hour minute part of the shaft.
Rotating lithophanes of your loved ones makes for a pretty cool project, and there isn’t a whole lot to this build to make it difficult. Much of it is 3D printed, including the tube in the center that the LED strip is wrapped around. The base is just big enough to hold the clock movement and the LED strip controller, so it would fit nicely on a desk or a mantel.
This is version two of [Chris]’ lithophane box, which gave him a chance to perfect the frame and design a thicker center post to withstand the heat from the LED strip. All the files are available if you want to print your own panels and take them for a spin. Since it’s so easy to change them out, you may end up with a big pile to choose from.
Clocks are a recurring feature among the projects we feature here on Hackaday, with several common themes emerging among them. We see traditional clocks with hands, digital clocks with all forms of display including the ubiquitous Nixie tube, and plenty of LED ring clocks. [Matt Evans]’s build is one of the final category, a particularly nice LED ring clock using wire-ended multi-colour LEDs. Other clocks produce an effect that looks good from across the room, but this one is also a work of beauty when examined in close-up.
Behind it all are four interlocking semicircular PCBs, an STM32F051C6T6 ARM Cortex M0 microcontroller which controls the clock, and a brace of driver chips. The different “hands” of the clock are expressed as different LED colours, and there is a variety of different colour and clock “hand” effects. An acrylic ring completes the effect, by covering the LEDs themselves. He’s put together a video of the clock in action, which you can see below the break.
Earlier in March we heard about a quirk of the interconnected continental European electricity grid which caused clocks to lose about six minutes so far this year. This was due to a slight dip in the mains frequency. That dip didn’t put anything out of commission, but clocks that are designed to accumulate the total zero-crossings of the power grid frequency of 50 Hz don’t keep accurate time when that frequency is, say 49.985 Hz for an extended period of time.
An interesting set of conversations popped up from that topic. There were several claims that modern alarm clocks, and most devices connected to mains, no longer get their clock timing from mains frequency. I’ve looked into this a bit which I’ll go into below. But what we really want to know is: are your alarm clocks and other devices keeping time with the grid or with something else?
Sometimes silence is the best compliment to a DIY project, and that doesn’t just apply to homemade lockjaw toffee. When a watch is so well-made that it looks like one from a jewelry store, it is easy to keep quiet. [ColinMerkel] took many pictures of his fourth wristwatch attempt but “attempt” is his word because we call this a success. This time around he didn’t forget the crown for adjusting the time so all the pieces were in place.
His second “attempt” at wristwatch making was featured here and it had a classical elegance. Here, the proverbial game has been stepped up. Instead of using stock steel, the body is constructed of 303 stainless steel. The watch dial will definitely draw compliments if its DIY nature is revealed, which is equally mathematical and charming. Pictures of this process were enough to convey the build without words which is always a bonus if you only want a quick look or English isn’t your first choice for language.
Like the look of Nixies but they just seem a little overdone? Or perhaps you just don’t want the hassles of a high-voltage power supply? Then maybe these faux-Nixie LED “tube” displays will find a way into your next clock build.
For his 2018 Hackaday Prize entry, [bobricius] decided that what the world needs is a Nixie that’s not a Nixie. To that end, each display is formed by seven surface-mount LEDs soldered to a seven-segment shaped PCB and slipped into a glass tube. The LEDs are in 4014 packages so they’re only 4 millimeters long, but what they lack in size they make up for in brightness. We’re not sure if it’s a trick of the camera, but the LEDs certainly seem to put off a bluish glow that’s reminiscent of vacuum-fluorescent displays — it’s like a Nixie and a VFD all rolled up in one package. The current case, which hides the clock circuitry on the lower part of the PCB, is just plastic, but this would look spiffy in a fine wooden case.
We’re big fans of the impractical around here at Hackaday. Sure there’s a certain appeal to coming up with the most efficient method to accomplish your goal, the method that does exactly what it needs to do without any superfluous elements. But it’s just not as much fun. If at least one person doesn’t ask “But why?”, then you probably left something on the table, design wise.
So when we saw this delightfully complex clock designed by [Tucker Shannon], we instantly fell in love. Powered by an Arduino, the clock uses an articulated arm with a UV LED to write out the current time on a piece of glow-in-the-dark material. The time doesn’t stay up for long depending on the lighting in the room, but at least it only takes a second or two to write out once you press the button.
Things are pretty straightforward inside the 3D printed case. There’s an Arduino coupled with an RTC module to keep the time, which is connected to the two standard hobby servos mounted in the front panel. A UV LED and simple push button round out the rest of the Bill of Materials. The source code is provided, so you won’t have to figure out the kinematics involved in getting the two servos to play nicely together if you want to try this one at home.
Revisiting old projects is always fun and this Nixie Clock by [pa3fwm] is just a classic. Instead of using transistors or microcontrollers, it uses neon lamps to clock and drive the Nixie Displays. The neon lamps themselves are the logic elements. Seriously, this masterpiece just oozes geekiness.
Inspired by the book “Electronic Counting Circuits” by J.B. Dance(ZIP), published in 1967, we covered the initial build a few years back. The fundamental concept of operation is similar to that of Neon Ring Counters. [Luc Small] has a write-up explaining the construction of such a device and some math associated with it. In this project, [pa3fwm] uses modern day neons that you find in indicators, so his circuit is also updated to compensate for the smaller difference in striking and maintaining voltages.
The original project was done in 2007 and has since undergone a few upgrades. [Pa3fwm] has modified the construction to make it wall mounted. Even though it’s not a precise timekeeper, the project itself is a keeper from its time. Check out the video below for a demonstration.