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

July 4, 2025 by 12 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.

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Hackaday Podcast Episode 327: A Ploopy Knob, Rube-Goldberg Book Scanner, Hard Drives And Power Grids Oscillating Out Of Control

July 4, 2025 by 2 Comments

It’s Independence Day here in the USA, but if you’re not a fan of fireworks and hot dogs, Elliot and Dan’s rundown of the best hacks of the week is certainly something to celebrate. Rest easy, because nothing exploded, not even the pneumatic standing desk that [Matthias] tore into, nor the electroplated 3D prints that [H3NDRIK] took a blowtorch to. We both really loved the Ploopiest knob you’ve ever seen, which would be even Ploopier in anodized aluminum, as well as an automatic book scanner that takes its job very seriously. We looked into the mysteries of the Smith chart, another couple of fantastic student projects out of Cornell, the pros and cons of service loops, and what happened when the lights went out in Spain last Spring. And what does Janet Jackson have against laptops anyway?

 

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Smart Temp Sensors Helps You Nail Your Cooking

July 4, 2025 by 21 Comments

Cooking is all about temperature control: too cold isn’t good enough, and too hot can ruin everything. To aid in this regard, [Printerforge] created a smart temperature alarm to keep them aware of exactly what’s going on in the pot.

The device is simple — it uses an Arduino Nano hooked up to a thermistor to measure the temperature of fluid in a pot. The microcontroller displays the current temperature and the target temperature on a simple 16×2 character LCD. Upon the fluid reaching the target temperature, the alarm is sounded, indicating that the cooking has reached a given stage or must otherwise be seen to. The whole build is wrapped up in a simple 3D printed case, along with a lithium-ion cell with charging managed via a TP4056 module.

If you’re regularly letting your pasta overcook or your stews burn in the pot, this kind of tool could be useful for you. Similarly, if you’ve ever wanted to pursue the 64-degree egg, this could be a way to do it.  The trick is to make sure you build it safely—ensuring that any parts that come into contact with the food are rated as food safe for your given application.

If this build has you contemplating the possibilities of machine-assisted cooking, you might like to go even further. How about getting involved in the world of sous vide? Meanwhile, if you’ve got any kitchen hacks of your own, don’t hesitate to let us know on the tipsline!

Why GitHub Copilot Isn’t Your Coding Partner

July 4, 2025 by 78 Comments

These days ‘AI’ is everywhere, including in software development. Coming hot on the heels of approaches like eXtreme Programming and Pair Programming, there’s now a new kind of pair programming in town in the form of an LLM that’s been digesting millions of lines of code. Purportedly designed to help developers program faster and more efficiently, these ‘AI programming assistants’ have primarily led to heated debate and some interesting studies.

In the case of [Jj], their undiluted feelings towards programming assistants like GitHub Copilot burn as brightly as the fire of a thousand Suns, and not a happy kind of fire.

Whether it’s Copilot or ChatGPT or some other chatbot that may or may not be integrated into your IDE, the frustration with what often feels like StackOverflow-powered-autocomplete is something that many of us can likely sympathize with. Although [Jj] lists a few positives of using an LLM trained on codebases and documentation, their overall view is that using Copilot degrades a programmer, mostly because of how it takes critical thinking skills out of the loop.

Regardless of whether you agree with [Jj] or not, the research so far on using LLMs with software development and other tasks strongly suggests that they’re not a net positive for one’s mental faculties. It’s also important to note that at the end of the day it’s still you, the fleshy bag of mostly salty water, who has to justify the code during code review and when something catches on fire in production. Your ‘copilot’ meanwhile gets off easy.

Using an SMD capacitor as a clip for flash media on a circuit board.

SMD Capacitor Doubles As Cheap SD Card Latch

July 4, 2025 by 41 Comments

Here’s a clever hack. Simple, elegant, and eminently cost-effective: using an SMD capacitor to hold your flash media in place!

This is a hack that can pretty much be summed up with just the image at the top of the page — a carefully placed SMD capacitor soldered to a routed tab makes for an extremely cost effective locking mechanism for the nearby SD card slot. There’s just enough flexibility to easily move the capacitor when its time to insert or eject your media.

It’s worth noting that the capacitor in this example doesn’t even appear to be electrically connected to anything. But there’s also no reason you couldn’t position one of the capacitors in your existing bill of materials (BOM). This form of mechanical support will be much cheaper than special purpose clips or mounts. Not a big deal for low-volume projects, but if you’re going high-volume this is definitely something to keep in mind.

If you’re just getting started with SMD capacitors then one of the first things to learn is how to solder them. Also, if you’re hoping to salvage them then try to look for newer equipment which is more likely to have SMD components than through-hole. If you’re planning to use your capacitors for… “capacitance” (how quaint), you can start by learning the basics. And if you want to know everything you can learn about the history of capacitors, too.

Thanks to [JohnU] for writing in to let us know about this one. Have your own natty hacks? Let us know on the tipsline!

Pez Blaster Shoots Candy Dangerously Fast

July 3, 2025 by 3 Comments

You could use a little pocket-sized Pez dispenser if you’re a humble, reserved person. Or, you could follow the example of [Backhaul Studios], and build a dangerously powerful blaster that shoots Pez fast enough to shatter them into pieces. Just don’t aim it at your own mouth.

As the video explains, Pez is really the perfect candy for this application. It’s compact, hard, and already designed to be dispensed via a magazine. It’s thus not a big stretch to set it up to be fired out of a pistol-like blaster. The build is of the flywheel type, where a pair of counter-rotating wheels fling the candy out at great speed. The wheels themselves are spun up to high speed with a pair of small brushless motors, running off hobby speed controllers and lithium-ion batteries. A simple trigger mechanism dispenses the rectangular candies into the wheel mechanism, sending them flying out of the blaster at will. It’s all 3D-printed, designed specifically for the purpose of high-speed candy delivery.

The video goes into great detail on the design, from the development of the TPU treads on the flywheels and other details that helped improve the effectiveness of the design. The final build shoots Pez fast enough that they practically detonate upon hitting a surface.

We’ve featured some innovative work in this space from [Backhaul Studios] before—the condiment cannon was really quite something. Video after the break.

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AI Might Kill Us All (With Carbon Emissions)

July 3, 2025 by 39 Comments

So-called artificial intelligence (AI) is all the rage right now between your grandma asking ChatGPT how to code in Python or influencers making videos without having to hire extras, but one growing concern is where the power is going to come from for the data centers. The MIT Technology Review team did a deep dive on what the current situation is and whether AI is going to kill us all (with carbon emissions).

Probably of most interest to you, dear hacker, is how they came up with their numbers. With no agreed upon methods and different companies doing different types of processing there were a number of assumptions baked into their estimates. Given the lack of information for closed-source models, Open Source models were used as the benchmark for energy usage and extrapolated for the industry as a whole. Unsurprisingly, larger models have a larger energy usage footprint.

While data center power usage remained roughly the same from 2005 to 2017 as increases in efficiency offset the increase in online services, data centers doubled their energy consumption by 2023 from those earlier numbers. The power running into those data centers is 48% more carbon intensive than the US average already, and expected to rise as new data centers push for increased fossil fuel usage, like Meta in Louisiana or the X data center found to be using methane generators in violation of the Clean Air Act.

Technology Review did find “researchers estimate that if data centers cut their electricity use by roughly half for just a few hours during the year, it will allow utilities to handle some additional 76 gigawatts of new demand.” This would mean either reallocating requests to servers in other geographic regions or just slowing down responses for the 80-90 hours a year when the grid is at its highest loads.

If you’re interested in just where a lot of the US-based data centers are, check out this map from NREL. Still not sure how these LLMs even work? Here’s an explainer for you.