Mysterious Files PH

Zinc air batteries have been a familiar sight for decades in the world of photography, where they provided an environmentally less dangerous alternative to mercury cells. They operate by the oxidation of metallic zinc using air, and the zinc comes in the form of a paste spread between two electrodes. Can their astounding energy density be harnessed for something useful? [ZollerLab] has designed a zinc air battery to find out, and is using it to power a rudimentary model car.

The video below is in German so you’ll have to enable translated subtitles if you’re an Anglophone, and it’s very long. But it goes into extreme detail on the chemistry, construction, and constraints of a zinc-air battery, and describes the system in this design. It’s a stack arrangement, in which the cells are held together on threaded rods, and pushed into each other with springs.

We think the car model is intended to demonstrate that this battery chemistry might one day be used in automotive applications. It’s not such a far-fetched idea given the low cost, relatively low environmental footprint, and high energy density, indeed we’ve heard of similar experiments with aluminium primary cells. But in this case we can see it provides the hacker with another route for their experiments, and that’s no bad thing.

Glass-based substrates are slowly beginning to push out organic substrates commonly used in PCBs due to often superior material properties. One area where glass substrates have however struggled is with through-hole vias and providing the conductive copper path through them. A 2024 article by [Keith Best] gives a good overview of the topic, with recent news showing how much companies like Intel are pushing for glass substrates, specifically for the packaging of dies.

One major advantage with vias in glass substrates is that they can be much smaller, enabling smaller than 0.1 mm diameter holes with far finer pitch. The challenge here is to make perfect holes with a laser that are defect-free, as well as have the intended diameter.

After that this through-glass via (TGV) has to be coated or filled with copper, much like their organic equivalent. Said TGV can be fully filled with copper, or use plating and add dielectric filler. Detecting flaws in such a finished TGV is important.

In a 2025 review article of glass substrate technologies by [Pratik Nimbalkar] et al. published in Chips the state of the art at the time was covered. The need for ever higher-density integration options with ASICs is highlight here, especially now that many chips today consist of multiple interconnected dies inside a single package.

The complications of creating TGVs with femtosecond laser pulses in Borofloat 33 glass are highlighted by [Daniel Franz] et al. in a 2025 research article, with microcracks and backside ablation observed without proper precautions, something which previously was often resolved by an etching step following said laser drilling. The main issue here is the post-drilling residual stress from the thermal shock, which the authors demonstrate can be largely prevented with careful tweaking of the laser drilling parameters.

As pointed out in a 2024 review article by [Chen Yu] et al. glass substrates are useful for far more than just high-density chip packaging. Glass substrates are also chemically resistant, have a higher heat resistance, are largely transparent to RF and can be hermetically sealed against outside influences. This makes them great for various advanced sensors and communication devices.

Meanwhile, if you wanted to do some metal-depositing on glass at home, we covered this recently.

There are many ways you can implement an Intel i386 CPU on an FPGA, with the use of original microcode probably being one of the most interesting approaches. This is what [nand2mario]’s z386 project does, with a recent blog post summarizing development on this FPGA project so far.

This project is similar to the previously developed z8086 project, which as one may guess does something similar, except for the Intel 8086 CPU. By executing the original microcode you’re basically guaranteeing close compatibility with the original hardware, though of course the sheer scale of this microcode between an 8086 and 80386 is quite different.

There’s a much larger instruction set with a correspondingly much more complicated internal state to keep track of, including all those newfangled features like memory management, paging and register debugging, as well extensions to protected mode that began with the i286.

Currently z386 runs on a number of FPGAs, including the Altera Cyclone V and Gowin GW5A, with performance equivalent to a ~70 MHz i386 albeit with slightly worse cycle efficiency, some of which could be due to the limited 16 kB cache compared to the 32+ kB cache in the fastest i386 CPUs. Either way, it’s more than enough to run all kinds of software, including games like DOOM.

Important to note is that the goal here isn’t to be more performant than cores such as for example ao486, but more as an archaeological reconstruction of the original hardware and its interaction with said microcode.

Top image: line-up of Intel 286, 386 and 486 CPUs. (Credit: Sgroey, Wikimedia)

Some of you may know there’s a version of UNIX for the Commodore Amiga, aptly called Amiga Unix or AMIX. There is an almost complete record of versions from 1.0 to 2.03, but 2.02 was lost media–until [Forgotten Computer] found it on an old Amiga.

It starts with an auction held for the 40 year anniversary of the Free Software Foundation where, by just one second, the highest bidder was too late. What do you do first with an artifact as valuable as an old FSF computer? You image the hard drive. Then you make several copies, including on different computers–after all, you wouldn’t want to lose the data on it. Preservation secured, the natural next thing is to boot it–and that’s when we see the magic 2.02c version number.
According to thorough digging by [Forgotten Computer], this version was–until now–lost.

In the video after the break, [Forgotten Computer] goes over what Amiga Unix is, the discovery process, and explores what’s on the disk–including FSF staples like GCC, G++ and core utilities like GNU less.

Thanks to [Stephen Walters] for the tip!

Unless you’ve managed to avoid touching a Windows computer until after the Windows XP era, it’s pretty good odds you’ve played Space Cadet Pinball. Some of you may have even paid for the Mac port of Full Tilt! Pinball, the actual game the Windows freebee was supposed to demo. Unofficial ports exist for Linux as well, which means the one place nobody has ever played the game is, ironically, on a pinball table. [CNCDan]aims to change that in a video embedded below.

Ironically given [CNCDan]’s name, the parts he starts with — the two sorts of pop bumpers, the drop targets, slingshots, and delayed-drop hole– are all largely 3D-printed. While some of these parts are available commercially, it turns out that the scaling of the virtual pinball machine doesn’t match anything on offer, and rather than compromise [CNCDan] decided to do it himself, an attitude we absolutely respect.

All that’s left are the flippers– his first prototype wasn’t powerful enough–and a couple minor mechanisms before building the table. To do that, he’ll need high-resolution art worth printing. Not surprisingly, a game dating from 1995 doesn’t have high resolution assets available with which to do that. That kind of creativity isn’t in [CNCDan]’s wheelhouse, so if it is in yours and you want to collaborate, or know someone who does, you can reach [CNCDan] at his YouTube page. At the very least, he can pay you in playtime.

[CNCDan] often goes beyond his namesake, like with his SteamDeck-like handheld, or his 3D printed VR headset. Still, no guesses how he’s going to build the cabinet.

With so many online messaging services to choose from it’s almost as though the daddy of them all, email, has faded into the background as something you only use for more formal contacts. But it’s still the underpinning of much of the business world’s electronic communication and is likely to stay so for the foreseeable future. The BBC Archive takes us back to a time when email was relatively new, when in 1986 [Lesley Judd] takes a very chunky 1980s laptop on a plane from London to the Netherlands, and sends an email to her colleague at home using a payphone and an acoustic coupler.

There are so many of-their-era quirks in this film it’s difficult to pick, but little things like the aircraft still having smoking and non-smoking areas, there being no sign of a mobile telephone, or the payphone operating in Guilders rather than Euros make it from a different time. Perhaps most interesting though is the email system in use, because this isn’t an internet based service. Instead it’s using Telecom Gold, which was the UK telco BT’s online service offering to businesses, and part of the international Dialcom network. This was a commercial service which  hung on until some time in the 1990s when the Internet finally displaced it.

The British writer L. P. Hartley used the phrase “The past is a foreign country; they do things differently there” as the opening sentence of one of his books, and the film below the break certainly brings that to mind. It’s a time that’s within reach, yet the changes in information technology over even the next decade or so would make the tech depicted not just obsolete but almost unrecognizable. Most of us today could sit at a 1996 laptop and send an email, but few of us would be as immediately at home with Telecom Gold.

It’s still possible to use an acoustic coupler today though.

If your first-generation Chromecast was acting a little wonky this week, don’t worry. Contrary to fears online, the 2014 device hasn’t been excommunicated by Google. In a statement to Ars Technica, a rep for the search giant explained that the issue, which was keeping the devices from being able to stream video from services like Netflix, was temporary and should now be resolved. That said, the OG Chromecast hasn’t officially been supported since 2023, so it’s not clear how much longer they will remain operational. Google be Google, after all.

After resisting for years, this week, Mozilla finally relented and brought Web Serial to Firefox. While there’s been some debate about the wisdom of letting the Internet directly talk to hardware gadgets, anyone who’s flashed Meshtastic or configured their Betaflight-powered drone from the browser can attest to how convenient it is. In the announcement, Mozilla acknowledges that “most folks won’t use this API”, but points out that the “community of builders and tinkerers” (that’s us!) is sure to be excited about the news. They’ve even teamed up with Adafruit to ensure their web-based microcontroller workflows are compatible in Firefox 151 and beyond. If you give it a shot, let us know how it goes.

Speaking of hardware support, the Linux Vendor Firmware Service (LVFS) recently picked up a couple of big-name sponsors. As reported by It’s FOSS, this week, Lenovo, Dell, and HP have signed on as Premier-level sponsors to the tune of $100,000 per year. For those unfamiliar, LVFS offers a central repository where hardware vendors can upload firmware updates. On the client side, fwupd can be used to pull these updates down automatically without having to hunt around on each vendor’s website. The experienced players don’t need a service like LVFS, but it’s certainly one of those quality-of-life improvements that make the desktop experience a bit more accessible.

While on the subject of getting hardware working, we hear that more PlayStation 5 consoles can now run Linux. Last month, a software solution for booting the operating system on PS5 consoles running the relatively ancient 3.x and 4.x firmware was released, but now developer Andy Nguyen has gotten it working on firmware 5.x and at least some versions of 6.x. That’s still considerably behind Sony’s latest release, but it does open things up for more consoles to get in on the action.

In space news, the successful first flight of Starship V3 has understandably dominated the headlines for the last few days, but SpaceX wasn’t the only commercial launch provider with good news this week. On Friday, Blue Origin announced they had completed the investigation into the failure of its New Glenn rocket back on April 19th and that the Federal Aviation Administration has approved its return to flight.

According to a statement from the FAA, Blue Origin “identified the direct cause of the mishap as a cryogenic leak that froze a hydraulic line and led to a thrust anomaly during the second stage engine burn.” This resulted in the payload, a next-generation communications satellite featuring a massive 2,400 sq ft deployable antenna array developed by AST SpaceMobile, being placed in an unsustainable orbit.

If you’ve always dreamed of piloting your own walking battle tank, you might finally be in luck. China’s Unitree Robotics has unveiled a mech standing 2.7 meters tall, complete with a promotional video showing it smashing cinder blocks. Because what else would you do with a robot you just paid more than half a million dollars for? Unfortunately, there isn’t much information about the bot’s speed or endurance, and a company spokesperson says the design still needs some refinement before it is ready for production. But still, we’re getting there. Might as well start saving up now.

Finally, we were thrilled to hear that the iconic soundtrack for DOOM has been inducted into the National Recording Registry by the Library of Congress. There’s perhaps no piece of software more emblematic of the hardware hacking world than the 1993 shooter, and while we don’t think that had anything to do with the decision to formally recognize the game’s heavy metal-inspired digital riffs, it will be all that much sweeter the next time we see some oddball gadget running through E1M1.

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