Making A Cardboard Airplane Wing

October 24, 2025 by Fenix Guthrie 1 Comment

Ideally, an aircraft would be made of something reasonably strong, light, and weather resistant. Cardboard, is none of those things. But that did not stop [PeterSripol] from building an ultralight wing out of cardboard.

Firstly, he wanted to figure out the strongest orientation of the cardboard flutes for the wing spars. He decided on a mix of horizontal and vertical flutes for the wing spar, with the horizontal flutes resisting vertical deformations and the vertical flutes resisting chord wise deformations.

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Tiny UPS Keeps WiFi Online

October 24, 2025 by Bryan Cockfield 6 Comments

For any mission-critical computer system, it’s a good idea to think about how the system will handle power outages. At the very least it’s a good idea to give the computer enough time to gracefully shut down if the power outage will last for an indefinite time. But for extremely critical infrastructure, like our home Wi-Fi, we might consider a more long-term battery backup that can let us get through the longest of power outages.

Part of why this project from [Next Builder] works so well is that most off-the-shelf routers don’t actually use that much energy. Keeping that and a modem online when the power is out only requires a few lithium batteries. To that end, three lithium ion cells are arranged in series to provide the router with between 9 and 12 volts, complete with a battery management system (BMS) to ensure they aren’t over- or under-charged and that they are balanced. The router plugs directly into a barrel jack, eliminating any switching losses from having to use an inverter during battery operation.

While [Next Builder] is a student who lives in an area with frequent interruptions to the electricity supply, this does a good job of keeping him online. If you’re planning for worse or longer outages, a design like this is easily adapted for more batteries provided the correct BMS is used to keep the cells safely charged and regulated. You can also adapt much larger UPS systems to power more of your home’s electrical system, provided you can find enough batteries.

The Isetta TTL Computer Makes Some Noise

October 24, 2025 by Jenny List 3 Comments

Our Hackaday colleague [Bil Herd] is known for being the mind behind the Commodore 128, a machine which famously had both a 6502 and a Z80 processor on board. The idea of a machine which could do the job of both those processors in hardware while containing neither would have blown the mind of any 1980s computer enthusiast, yet that’s exactly what [Roelh]’s Isetta TTL computer does. It’s an extremely clever design whose targeted microcode allows the processor-swap trick, and since he’s brought it from prototype to production and has it running SymbOS since we last saw it, it’s time we gave it another look.

A diagram showing chip placement on the Isetta PCB. — All the functions on what is a surprisingly compact board.

The video below the break shows the machine in action, with the Windows 95-like SymbOS GUI running a series of sound tests in the emulated AY-3-8910 sound generator, as well as a Lemmings-like game. It also runs Sinclair ZX Spectrum software, giving it access to a huge library.

We were lucky enough to see some of this in person when we encountered it for a second time on our travels during the summer — and it’s just as impressive in the real as it looks in the video. The feeling really hits you of how this would have blown away anything on the 8-bit market in 1985, made more impressive by the silicon in use being not too far from what was available at the time.

We’re told you can now buy one for yourself as a kit, and we’re looking forward to seeing it generate an ecosystem. We’re particularly curious as to whether that retargetable microcode could allow it to support other archetctures of the day.

Our original coverage can be read here, and we’ve also touched upon SymbOS.

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Hackaday Podcast Episode 343: Double Component Abuse, A Tinkercad Twofer, And A Pair Of Rants

October 24, 2025 by Kristina Panos No comments

This week, Hackaday’s Elliot Williams and Kristina Panos met up across the universe to bring you the latest news, mystery sound, and of course, a big bunch of hacks from the previous seven days or so.

In Hackaday news, OMG Supercon is almost here! And we just revealed the badge! In other news, we’ve still got a contest running. Read all about the 2025 Component Abuse Challenge, sponsored by DigiKey, and check out the contest page for all the details.

On What’s That Sound, Kristina failed spectacularly. Will you fare better and perhaps win a Hackaday Podcast t-shirt? Mayhap you will.

After that, it’s on to the hacks and such, beginning with a really cool entry into the Component Abuse Challenge wherein a simple transmission line is used to multiply a voltage. We watch as a POV globe takes to the skies, once it has enough motors.

Then we discuss several awesome hacks such as an incredible desk that simulates beehive activity, a really great handheld PC build, and a Tinkercad twofer. Finally, we discuss the future of removable batteries, and the history of movable type.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download in DRM-free MP3 and savor at your leisure.

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Making WiFi Sound Like Dial-Up Internet

October 24, 2025 by Lewin Day 3 Comments

Dial-up modems had a distinctive sound when connecting, with the glittering, screeching song becoming a familiar melody to those jumping online in the early days of the Internet. Modern digital connections don’t really have an analog to this, by virtue of being entirely digital. And yet, [Nick Bild] decided to make WiFi audible in a pleasing tribute to the modems of yore.

The reason you could hear your dial-up modem is because it was actually communicating in audio over old-fashioned telephone lines. The initialization process happened at a low enough speed that you could hear individual sections of the handshake that sounded quite unique. Ultimately, though, once a connection was established at higher speed, particularly 33.6 k or 56 k, the sound of transmission became hard to discern from static.

Modern communication methods like Ethernet, DSL, and WiFi all occur purely digitally — and in frequencies far above the audible range. Thus, you can’t really “listen” to a Wi-Fi signal any more than you can listen to the rays of light beaming out from the sun. However, [Nick] found an anachronistic way to make a sound out of WiFi signals that sounds vaguely reminiscent of old-school modems. He used a Raspberry Pi 3 equipped with a WiFi adapter, which sniffs network traffic, honing in on data going to one computer. The packet data is then sent to an Adafruit QT Py microcontroller, which uses the data to vary the amplitude of a sound wave that’s then fed to a speaker through a digital-to-analog converter. [Nick] notes this mostly just sounds like static, so he adds some adjustments to the amplitude and frequency to make it more reminiscent of old modem sounds, but it’s all still driven by the WiFi data itself.

It’s basically WiFi driven synthesis, rather than listening to WiFi itself, but it’s a fun reference to the past. We’ve talked a lot about dial-up of late; from the advanced technology that made 56 k possible, to the downfall of AOL’s long-lived service. Video after the break.

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This Week In Security: Court Orders, GlassWorm, TARmageddon, And It Was DNS

October 24, 2025 by Jonathan Bennett 2 Comments

This week, a US federal court has ruled that NSO Group is no longer allowed to use Pegasus spyware against users of WhatsApp. And for their trouble, NSO was also fined $4 million. It’s unclear how much this ruling will actually change NSO’s behavior, as it intentionally stopped short of applying to foreign governments.

There may be an unexpected source of leverage the US courts can exert over NSO, with the news that American investors are acquiring the company. Among the requirements of the ruling is that NSO cannot reverse engineer WhatsApp code, cannot create new WhatsApp accounts, and must delete any existing WhatsApp code in their possession. Whether this actually happens remains to be seen.

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Robot Phone Home…Or Else

October 24, 2025 by Al Williams 53 Comments

We would have enjoyed [Harishankar’s] tear down of a robot vacuum cleaner, even if it didn’t have a savage twist at the end. Turns out, the company deliberately bricked his smart vacuum.

Like many of us, [Harishankar] is suspicious of devices beaming data back to their makers. He noted a new vacuum cleaner was pinging a few IP address, including one that was spitting out logging or telemetry data frequently. Of course, he had the ability to block the IP address which he did. End of story, right?

No. After a few days of working perfectly, the robot wouldn’t turn on. He returned it under warranty, but the company declared it worked fine. They returned it and, indeed, it was working. A few days later, it quit again. This started a cycle of returning the device where it would work, it would come home and work for a few days, then quit again.

You can probably guess where this is going, but to be fair, we gave you a big hint. The fact that it would work for days after blocking the IP address wouldn’t seem like a smoking gun in real time.

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