When Changing Scale Isn’t Just More Of The Same

July 11, 2026 by Elliot Williams 2 Comments

[Jenny] and I were talking about [Bitluni]’s experiment in scale, where he will take 65,536 cheap microcontrollers, network them all together, and give each one an RGB pixel. From there, antics will surely ensue. Right now, he’s only got 8,192 of them up and running, and already the novel problems and opportunities are rearing their heads.

We all know it from our own hacking. In theory, doing something ten times is ten times doing it once. But then in practice, entirely new phenomena appear as you scale up that were simply not there in the small. Maybe it happens when you repeat it one hundred times, or a thousand.

Viewed positively, this is the property of emergence: how the whole can be more than the sum of its parts, and how biology isn’t just chemistry multiplied by a few million interactions. In our blinky world, a massive wall of LEDs is a display, not just a bunch of pixels.

On the flip side, going from one microcontroller with a 10 mA current draw to 64 Ki controllers, with 655 A, is more than just a difference in scale. You need to learn a new skill set to handle the problem. Making a single prototype is a different problem from making a run of badges for a conference of 5,000 – you’ll need a team, and won’t be able to just hack it alone – not to even mention the parts sourcing woes.

So I loved watching [Bitluni] going through the upscaling. He certainly had an idea of what he was getting himself into, but as with the emerging properties of a big system, there are often emerging problems, and those you can’t always see ahead of time. Have you gotten into a project that scaled itself into something qualitatively different? Tell us about it.

When An Engineering Education Doesn’t Teach You How To Really Make Anything

July 7, 2026 by Jenny List 105 Comments

In the sweltering temperatures of an unusually hot European heatwave, I found myself having a chat with a friend of mine from my university days. After discussing the health of his cat who had solved the problem of a fur coat on a hot day by flattening himself out on the concrete floor in the coolest place in the house, we moved on to tech matters. We’ve known each other for not far short of four decades, so this is familiar territory for us. The problems that come with taking a prototype to manufacturing, a process which even the most seasoned of engineers can slip up on.

The Difference Between Making, And Making For Manufacture

If you’ve ever taken a project and replicated it, you will know the progression. If you’re making five or ten widgets, you can debug and rework as needed, tweak things, and get things going. If you’re making more then this, the process consumes a greater proportion of your time, until a point at which manufacture becomes impractical. Maybe that’s around fifty boards, sometimes more or less. Continue reading “When An Engineering Education Doesn’t Teach You How To Really Make Anything” →

Ask Hackaday: What Ever Happened To The Hero Nerd?

June 17, 2026 by Tom Nardi 178 Comments

Knowing absolutely nothing about you other than the fact that you’re currently reading Hackaday, I can predict with a high degree of certainty that we’re both fond of at least a few of the same movies. That’s not to say they’re necessarily our favorite works of art. Indeed, in some cases they may even be objectively bad films. But the memory of them has stuck with us — and by extension nearly everyone else in the hacker and maker community — for decades.

Even if you don’t remember all the little details, you’ll never forget the names: movies like WarGames, Ghostbusters, Back to the Future, and Short Circuit. Stories that showed smart people using their intellect and a bit of cobbled together hardware to triumph over the bad guys. The tech wasn’t always believable, sometimes it was downright farcical. But they made it seem real, and by the end of the story when they won the day using brains and a soldering iron rather than fists or a gun, the minutia of how it all worked wasn’t really that important anyway.

It’s not a stretch to say that films such as these helped put many of us on a path towards science and technology. For those with an interest in more cerebral pursuits, seeing a scientist or an engineer save the day was hugely influential. How many engineers got their start watching Scotty frantically eke just a bit more power out of the Enterprise?

But as we recently discussed some of these classic movies behind the scenes here at Hackaday, it struck us that all of the best examples we could come up with were now 20, 30, or even 40 years old. That’s not to say there aren’t a few contemporary standouts, but they mostly seem to be biopics or other historical dramatizations which don’t quite scratch the same itch. Even so, none of them appear to have had the cultural impact necessary to stand the test of time in the same way their predecessors have.

So where have all of Hollywood’s heroic nerds gone, and what does it mean for future generations if these niche role models are no longer represented?

Continue reading “Ask Hackaday: What Ever Happened To The Hero Nerd?” →

Patterns Everywhere

June 13, 2026 by Elliot Williams 23 Comments

I studied physics in college, and I’m always surprised how fundamental some of the concepts are. Take waves for example. You really wouldn’t expect the same underlying concept to be at work on surface of a pond, the string of a guitar, light passing through two slits, and then in the probabilistic behavior of electrons orbiting inside nuclei. But here we are, in a world filled with wave-like phenomena.

What little control theory I know, I’ve learned in the school of hard knocks. But it’s equally amazing that the same basic concepts govern the tuning of car shock absorbers, PID controllers, active audio filters, and other more complex systems where feedback matters. Crucial in all of these systems is the judicious balance of amplification and damping.

And last week on vacation, learning to drive a covered wagon pulled by a heavy draft horse, I saw the same patterns again. The horse likes to pull, and when the wagon comes over the crest of the top of a hill, it starts to roll forward into his harness, pushing him from behind. This makes the horse uneasy, and he slows down, the wagon pushes him harder, and positive feedback gets out of control.

The man who was teaching me to drive the wagon said, “it’s not like a car” in that you don’t tap the brakes to slow down and then let go. Rather, you hold on the brakes for a lot longer than you think is necessary – until the horse tells you that he feels like pulling again – and then you let up only a tiny bit at a time. Otherwise, you end up in the under-damped case, where you let the wagon go too much, it slows the horse, you slam the brakes, the horse pulls hard, and you let up on the brakes, and the cycle continues anew.

What he meant by “not like a car” was that the brakes aren’t just slowing down the wagon, they’re adding damping to keep the horse-wagon system from oscillating. Once that clicked in my mind, everything was smooth sailing. After a couple of days, I even started adding some feed-forward to my mental PID controller, letting the brakes go a little bit more when the horse was approaching the bottom of a hill, and he obviously wanted to pick up a little more speed before the grade ahead.

The horse seemed happy that I was finally getting it, but I don’t think he had any understanding of tuning PID loops. He did have me pondering, on a long stretch of rolling hills on a summer morning, if there were a good minimal set of patterns that explained a maximal breadth of phenomena. I’m starting with the physics of waves and the control of feedback systems, but what’s next?

Between-Device Sharing Still Sucks

May 20, 2026 by Zoe Skyforest 129 Comments

Once upon a time, computing was simple. You had files on a floppy disk. If you wanted to take them to a different computer, you ejected the disk from one machine and put it in another. It wasn’t fast, but it was easy and intuitive. Besides, you probably only had one computer of your own, anyway.

Life has since gotten a lot more complex. You’ve got a desktop, a laptop, a work laptop, your personal and business phones, and a smart watch to boot. You live amongst a swirling maelstrom of terabytes of data. Despite all the technical advances that got you here, it’s still a pain to get a file from one device to another, even when they’re sitting on the same desk. Why?!

Continue reading “Between-Device Sharing Still Sucks” →

Ask Hackaday: Do We Need A 21st Century Calculator?

May 14, 2026 by Al Williams 80 Comments

The HP-41C analog on my phone gives the right answer.

Three resistors in parallel: 4.7 k,Ω 22 kΩ, and 3.3 kΩ. Quick! What’s the equivalent value? You can estimate it, of course, but if you want the actual 1.8 kΩ (approximately) answer, you probably reached for some kind of calculating aid. I have two slide rules on my desk, and plenty more a few steps away, but I don’t use them much, honestly. I have a very old HP-41C — arguably the best calculator ever made — but I am usually afraid to use it as it is almost 50 years old and difficult to repair. I also have an HP-28S on my desk, a replica HP-41C, and a few others in desk drawers. There are also dozens of calculators on my desktop computer, my phone –including the official HP Prime app — and the web browser.

I often see newer calculators from HP, like the Prime G2, or “new” HP-like calculators like the ones from SwissMicros, and think I should pick one up. Well, technically, HP licensed their calculators to Moravia, so even a “real” HP calculator isn’t from HP anymore. But, in the end, I always realize that my need for a physical calculator is so diminished that I can’t justify buying anything new, and I can barely even spring for a $10 one at the thrift store unless it is a real collectible.

Mind you, I’m not talking about RPN versus algebraic. I could say the same thing for TI, Casio, or Sharp calculators. I just don’t know why I need one anymore, even though I still, for some strange reason, want them.

The Prime seems impressive, if I could ever find time to finish reading the manual.

For the record, I did use an HP-41C to check the resistor math, but it was in the form of an app on my phone, not a real calculator. On the same computer I’m writing this on, I have HP-41C emulators, the Prime emulator, and a bunch of other calculators. Yet I still pick up my phone and use the familiar key layout of the HP-41C. I don’t know why. The replica 41C, unfortunately, has a landscape-oriented keyboard, so while I like it, it doesn’t satisfy my finger’s muscle memory.

Which leads to this Ask Hackaday. Do you use a calculator? Why? If you don’t, do you use a fake calculator on your phone or computer? Or do you just send your math to Google or Wolfram? I suspect some of the answer will be generational. I was in high school before calculators started showing up in schools, but they took over quickly.

There is something satisfying about having a purpose-built device to do your math. No long boot sequence. No switching apps. No messages coming in while you are typing in numbers. For the ultimate convenience, you could wear it on your wrist. The Apollo mission that docked with a Russian spacecraft carried an HP-65, and nine early Space Shuttle missions used an HP-41C. But even astronauts now don’t have a standard-issue calculator. Pilots sometimes use electronic E6Bs, but many still use the mechanical version.

Of course, I do collect slide rules, so maybe I just need to accept that calculators are yet another tech relic to collect. But someone is still buying them. I’d like to be one of them.

Continue reading “Ask Hackaday: Do We Need A 21st Century Calculator?” →

Copy Or Redesign?

May 9, 2026 by Elliot Williams 5 Comments

We got asked a great question in the mailbag segment on the Podcast this week: are there hacks that we have read about on Hackaday that we use in our everyday life? The answer was absolutely yes, and I loved Tom’s take it often goes the other way – he sees a hack, tests it out, and then writes it up.

But I started looking around the office and I found more examples of projects that were absolutely inspired by projects I had seen on Hackaday, yet weren’t the same. I made a DIY mechanical keyboard because I saw someone else do it. There are a few home-made battery packs that I probably wouldn’t have attempted without having read about someone doing the same thing. I riffed on [Ted Yapo]’s Tritiled project, making a slightly inferior, but workable knockoff, and they’ve been glowing for many years now.

That got me to thinking about reproducing a project versus taking inspiration from it, and though I enjoy both, I’m find myself most often in the “inspiration” mode. I just can’t leave well enough alone, even when I’m fundamentally copying someone. NIH syndrome? Expediency? Probably both, and sometimes with a dose of hubris or feature creep.

Looking back at [Ted]’s TritiLED, though, I found some great examples in both the rebuild and redesign modes on Hackaday.io. [schlion]’s Making Ted Yapo’s TritiLED couldn’t be a clearer example of the former, and it’s great to look over his shoulder and appreciate all the lessons he learned along the way. [Stephan Walter]’s Yet another ultra low power LED is inspired by [Christoph Tack]’s Ultra low power LED, which is in turn inspired by [Ted]’s project, like a conceptual grandchild.

In a way, I look at this like with music: sometimes you play the notes the way they were written down, and sometimes you riff on someone else’s theme. Both are equally valid, and both owe a debt to the upstream source. Is Hackaday the hackers’ jazz club? And which of these modes do you find yourself working in most?