ESP32 As Your Raspberri Pi’s Linux Wireless Co-processor

October 7, 2026 by 1 Comment

A laptop with no wireless connectivity feels like a rarity – but when you shop for powerful Linux single-board computers (SBCs), it is pretty common to see one skimp on WiFi. At the same time, current wireless cards can leave much to be desired. A mess of proprietary firmware, ephemeral or even binary blob drivers, weird glitches never resolved, and sometimes entirely source-less blobs with an expiration date. Maybe the SBC doesn’t have a free USB port for a plug-and-play WiFi chip, or you don’t want to design for an obscure hard-to-source castellated module.

What if I told you there’s a unique solution to the problem, as long as the SBC has an SDIO or SPI to spare? There’s a wireless card we can all try to get behind, and it’s certainly not flawless but gives us way more room to grow – it’s got somewhat open-source firmware, it comes from a respectable company, and it’s nigh-guaranteed to be easy to source. I am, of course, talking about esp-hosted – using ESP32 modules as your WiFi/BT card, over SDIO or SPI.

I’ve recently added an ESP32-C6 into my project, and setting up esp-hosted wasn’t ultra straightforward – so here’s a guide, and a discussion on what makes esp-hosted so cool and so incredibly promising. Spoilers: it works with privacy switches that cut out power, it could be hacked into a coprocessor for mesh protocols, and it could potentially help us build a fully open-source SDIO WiFi card.

Continue reading “ESP32 As Your Raspberri Pi’s Linux Wireless Co-processor” →

Don’t Try This At Home, Transcranial Magnetic Stimulation Edition

October 7, 2026 by 1 Comment

Transcranial magnetic stimulation is one of those things that seems too wacky to be true. Depression not responding to treatment? Let’s smack you upside the head with strong magnetic fields! As odd as it sounds, it’s actually very well studied and works often enough that it has been approved by regulatory agencies as real evidence based medicine.

It’s also now open source, thanks to the OpenTMS project by [Zach McGinty]. Though since its not approved by the FDA or your local authority, be very aware of [Zach]’s disclaimer that this is not a medical device and if you do build something based on the extensive data on his GitHub, you do so at your own risk.

He’s got plans for the coils that go next to your head — made of hollow copper pipe to carry coolant, just like the pros do it — and the power supply to pulse them with mind-altering amounts of electricity. That might be literal in this case, but it’s also a hefty power supply: a pair of microwave oven transformers, switched through IGBTs in a flyback configuration. We’re talking kiloamps here, so make sure you know what you’re about before you try putting that kind of power right next to your skull.

[Zach] did, and he’s still here. Though to be fair, we’re not sure if he’s a very good engineer or just very lucky. Given he’s isolated the IGBT gate controls with fiber optics, and seems to follow other best practices, we’re going to guess the former, but it might still be both.

Either way, this one is going firmly into the “don’t try this at home” bucket. Even so we’re happy to see more medicine go open source, be it assistive sip-and-puff pointing devices, or ESP32 electroencephalograms. If nothing else, it keeps the big boys on their toes, and that’s what hacking is all about.

The Commodore 64 Keyboard Font, For Everyone

October 7, 2026 by 15 Comments

There are some classic fonts which appeared in one place and became almost iconic, yet never made it into the digital age. The font on the Commodore 64 keyboard for example, with its its slightly narrow letters. If you’ve been yearning to see it again then help is at hand, because [Levente Szabadkai] has traced it from photographs and made it available as a vector font in a variety of formats on GitHub.

A font proof sheet for the C64 keyboard font.As you might expect, it’s an uppercase font only, as the hardware never sported lower case letters. But it doesn’t stop there, because it also contains the various punctuation and other marks, all the PETSCII glyphs, and the function keys. There’s even a Commodore logo for that key down in the left hand corner, but we’re guessing you’ll have to assemble CLR HOME yourself. We can’t help noticing the cursor arrows are solid in contrast to the outlined ones on our 64 here, but we’re guessing there may be some minor differences between models.

So download the font, and make all your stuff look like a 1980s home computer keyboard. And in case you are wondering why you find so many keyboard fonts familiar, we’ve talked about the Gorton font in the past.

[Avery] standing inside the inflating envelope of his airship

Don’t Worry, This R/C Airship Is Supposed To Be On Fire

October 6, 2026 by 4 Comments

We’ve had a lot of flying hacks here over the years, and that includes just about any way to get airborne you can think of — but very few of those have been airships. Fewer still have been 27-foot thermal airships, like the one [Avery Flies] designed and put together recently.

A thermal airship, in case the name doesn’t give it away, is a dirigible hot air balloon. Like a hot air balloon, it gets its lift from the density difference between hot air and the regular atmosphere. Unlike a hot air balloon, it has control surfaces and an engine so it goes where you tell it to. The craft uses good-old-fashioned radio control, and except for the nylon envelope he spends the first 15 minutes of the video below designing and sewing up, the technology mostly comes from be from the world of R/C aircraft.

The big exception is of course the a propane burner used to generate heat, said propane being supplied by a pair of small green tanks such as you might use on a portable barbecue. Everything that moves is electric, though: there’s a 70 mm (about 2¾“) electric ducted fan acting to push the air up into the balloon so it keeps shape, and a great big brushless DC motor pushing an 18” (about 457 mm) prop for thrust. The steering servo is actually a repurposed winch servo from an R/C sailboat, rather than anything from the world of model aircraft. But it makes sense, as the meter-scale fabric rudder is more like a sail than the control surfaces of most R/C aircraft.

You might expect a blimp to be the biggest flying machine we’ve featured on Hackaday, but some truly giant-scale R/C aircraft have come our way in the past. We’ve also seen some pretty teeny blimps.

Continue reading “Don’t Worry, This R/C Airship Is Supposed To Be On Fire” →

Upgrading An IPhone Lens To The Max

October 6, 2026 by 3 Comments

The camera in a typical mobile phone is now at a standard at which it can be considered a serious device rather than a toy, such has been the effort put in by the phone manufacturers. They are still held back in some ways by their lenses despite the same development effort being pointed in that direction, and there have been projects aiming to replace those lenses with better quality ones. A while back we covered [Evan Monsma]’s replacement of his broken iPhone camera lens with a C-mount item, and now he’s back with a much improved version.

The original was glued on with cyanoacrylate adhesive, and this had parted. It was time to upgrade the phone, so he had a new lens mount covering two of the cameras machined from solid brass and leaving an open view for the third and unmodified camera. This was fixed to the phone with epoxy, and with a set of 3D printed lens covers to protect them he’s ready to go. There’s even a tripod thread machined into the bottom of this thing. He shows us it in action with both C-mount and EF-mount lenses, the latter resulting in a very long effective focal length.

We like this project, but perhaps we’d give it an IR filter to remove the unwanted pink glow. If you’re interested, here’s the original version.

Continue reading “Upgrading An IPhone Lens To The Max” →

DIY Algae Biodiesel Is Harder Than You Think

October 6, 2026 by 36 Comments

There’s one thing [Silent H] wants you to know before you watch his video about making biodiesel, embedded below: he started this project before he’d even heard of the Strait of Hormuz. No, he’s just independent-minded and wanted to try making his own fuel when diesel was– in retrospect– cheap as chips. That’s probably a good thing, because while [Silent] gets his pint of fuel at the end of the video, it’s not from algae; it’s from a backup crop of sunflowers.

As it turns out, he picked what was the perfect algae and the absolute worst algae for making biodiesel from: Chlorella Vulgaris. It’s perfect because it’s easy to grow, and easy to extract from the growth medium, as it sinks when it is ‘ripe’, and has a very high oil content. Of course [Silent] didn’t want to toss algae cakes into a steam powered canoe, he wanted diesel fuel for his vehicle. That’s where the project broke down: Chlorella Vulgaris cells are exceptionally tough, and if you can’t rupture the cell wall, you can’t can’t get out any appreciable oil. A few grams by solvent extraction is all he manages before switching to more tractable feedstock.

That feedstock is sunflowers, which give up their oil through the application of violent pressure. That is to say, he crushes the seeds in an oil press. Oil acquired, he goes on to transesterfy the stuff, extracting glycerine to produce biodiesel– a process ripe for hacking that you’d think we’d cover more often.

We have covered the algae growth side of things before, but that algae seemed to be destined for other uses than fuel.

Continue reading “DIY Algae Biodiesel Is Harder Than You Think” →

SmallTV Hacking With Surprisingly Little Fuss

October 6, 2026 by 4 Comments

We’ve seen the GeekMagic SmallTV line of devices before — these cheap gadgets combine a microcontroller and a display in a little plastic case that can be used to show the time or weather. Powered by either an ESP8266 or an ESP32, the things could easily pass for a hobby build if it wasn’t for their professionally produced enclosures. In fact, we wouldn’t be surprised if GeekMagic lifted the idea from an existing DIY project.

As you might expect we’ve seen several hacks for these devices already, which usually involves replacing the stock firmware. But this latest approach is unique in that you don’t need to mess with the stock software, nor do you need to break out the soldering iron. By leveraging a built-in photo viewer function of the SmallTV [Yongha Kim] shows how you can get the gadget to display pretty much whatever you want.

The trick here is that the image is being generated by a machine on the network, say your desktop or server, and being pushed over to the SmallTV over HTTP. In this example the image is being generated in Python with the Pillow library, and [Yongha] has it showing Claude and Codex usage data, but you could really approach this however you wish.

All you need to do is create a 240×240 image and shoot it over to the device, so you’re free to come up with whatever sort of visuals you’d like. It even supports GIF if you’d like to work animation into it. The content can of course be whatever information you’re interested in showing, and it can be generated by whatever programming language or tool you’re most comfortable with. It’s a fascinating proof of concept, and now that the method has been demonstrated we’re interested to see where the community can take it.

If this all sounds a little too easy for your tastes, don’t worry. There’s a plenty deep rabbit hole you can dive into should you elect to replace the device’s firmware entirely.