In these days of cheap microprocessors and easy access to accurate timing through NTP or from the likes of MSF, WWVB, or DCF77, it’s no problem to ensure that any number of clocks keep the same time. In a simpler age though they didn’t have these tools at their disposal, so when a large organisation wished to ensure that all its parts ran on the same time they used an electromechanical solution. A master clock of as high a quality as the clockmakers of the day could build was fitted with a microswitch. The switch would send pulses to slave clocks which had a solenoid where a traditional clock has a pendulum. Thus every clock in the system lost or gained time at the same rate.
[Edo Lelic] has a rather nice Iskra slave clock, but unfortunately not the master that once drove it. Undeterred by this setback, he’s created an electronic driver board that generates the required 100mS pulses. His weapon of choice was a PIC microcontroller and an H-bridge driver to deliver their required voltage and polarity. The clock was designed to accept 100V pulses, but since it has an internal series resistor he determined that the solenoid was happy with a mere 24V. Source code is available, downloadable at the bottom of the linked article.
These clocks are an unseen piece of technology that is disappearing without our noticing. If you find one – or even better if you find a master clock – you’ll find it to be a very high quality timepiece indeed. A master clock would be well worth snapping up. At least now you won’t have to look too far for a driver for it.
If binary clocks have you confused by all the math required to figure out what time it is, we have the solution for you: a unary clock. After all, what’s simpler than summing up powers of two? Powers of one! To figure out the time, you start with the ones digit. If it’s on, you add one to the total. Then move on to the next digit. Since 12 equals one, you add another one if it’s lit. Then on to the third LED. 13 = 1, so if it’s lit, you add another one, and so on.
OK, we’re messing around. Calling this a “unary” clock is ridiculous. When it’s seven o’clock, there are seven LEDs lit. Nice and easy to read. Sixty minute LEDs is silly, so here each minute LED stands for five minutes. Good enough.
What we really like about this clock is the build. It’s intended as educational for school kids, so it has to be simple to build and easy to personalize. Building the body out of Lego bricks fits the specs nicely. Transparent Lego bricks are used to give the white LEDs some color. That was too bright, so [Shrimping It] added paper cutouts from a hole punch as diffusers.
For this clock, one of the many custom builds on [GMG]’s site that betray a certain passion for unusual timepieces, an 8×32 array of Neopixels lives behind a laser-cut sheet of steam-bent birch plywood. Each pixel is masked by either an alphanumeric character or an icon representing weather conditions. An ESP8266 fetches time and weather data and drives the display serially, controlling the color of each cell and building up the display. The video below shows the clock doing its thing.
Sure, we’ve featured plenty of word clocks before, even some with weather display, but we like the slim and understated design of this build. We’re particularly impressed by the lengths [GMG] took in packing as much capability into the 256-pixel display as possible, like the way “today” and “tomorrow” overlap. And if you’ve got an eye for detail, you might spot what gets displayed when it’s over 80° and 80% relative humidity.
Wait, plexitube? Is that a typo? Surely we mean Nixie tubes!
For a Christmas project [Kurt] wanted to build some owl-inspired clocks — with bit of a retro feel. Given the complexities of finding and using actual Nixie tubes, he went with an alternative — a Plexitube.
Plexitubes look like futuristic Nixie tubes. They can have different stylized numbers. They’re crisp, they’re bright, and they are completely customizable. They’re made of edgelit acrylic! By laser etching the design onto pieces of acrylic and feeding LED light into the edge, very much like how a light-pipe works, it’s possible to have a neon-light effect — using nothing more than plastic and some LEDs.
He designed custom PCBs for the project, with SMD LEDs for the plexitubes. Making use of a laser cutter, he designed the actual owl to be made out of lightly formed wood cutouts — the entire thing looks absolutely fantastic.
[Rjeuch] liked a wooden clock he saw on the Internet, but the gears were produced with a proprietary software tool. So he built his own version. Unlike the original, however, he chose to use a stepper motor to drive the hands.
The clock’s gears aren’t just for show, and the post does a good job explaining how the gears work, how you might customize them, and how they fit together. The clock’s electronics rely on an Arduino.
Nixie clocks. Nixie power meters. Nixie thermometers, speedometers, and even Nixies for personal adornment. Is there anything that hasn’t been Nixie-fied? How about a Nixie kitchen timer? Beyond the Nixie tube, this is a great build. Check out the video below the break.
As so often happens with Nixie aficionados, [Kouichi Kuroi] started with tubes and searched for a project to use them on. A wonky kitchen timer provided the thinly veiled excuse for the build – after all, anyone can drop a couple of yen on a commercial replacement, right? The timer features four IN-12 tubes and a large numeric keypad up front on a laser-cut acrylic case. For those who quibble with the keypad’s aesthetics and the wisdom of a Nixie project in the kitchen environment, [Ko] points out that an IP65 keypad would have more than doubled the price of the build, and a little common sense goes a long way to keeping the high-voltage side from meeting anything wet. In addition to countdown capability, the timer can also act as a stopwatch and display the time of day, and the Nixie tubes provide great visibility compared to seven-segment LCD timers.
[Stephen B.] kickstarted a MicroPython board. When he got it, he was pleasantly surprised to find that it worked great. His jaded soul balmed with a good experience, he found himself armed with a tool in search of a project. Then he remembered something that had stuck with him, which was a tide clock.
He lives 70 miles from the sea, but his stepmother had a birthday coming up. She went swimming daily, so he had his excuse to build. Unlike his inspiration project, a bunch of seven segment LEDs would not be received well by a technically disinclined stepmother with a well decorated home. So, instead of those, he went with an epaper display. It looks great.
He wanted to use the Kindle display to save money, but the weird power levels needed scared him off. He spent a bit more on a module, but it was probably worth it in time savings. Micropython board, an RTC, a battery, and e-paper display in hand, he had everything needed to build the clock but aesthetics.
Luckily a local frame shop entertained him by letting him pick up frames until he could find one that fit. He put a nice shoreline print together, installed the devices into the frame, and ended up with a really good looking clock. Sure it only tells time four times a day, but that’s enough if you live a life by the sea.