ISS Medical Emergency: An Orbital Ambulance Ride

January 15, 2026 by No comments

Over the course of its nearly 30 years in orbit, the International Space Station has played host to more “firsts” than can possibly be counted. When you’re zipping around Earth at five miles per second, even the most mundane of events takes on a novel element. Arguably, that’s the point of a crewed orbital research complex in the first place — to study how humans can live and work in an environment that’s so unimaginably hostile that something as simple as eating lunch requires special equipment and training.

Today marks another unique milestone for the ISS program, albeit a bittersweet one. Just a few hours ago, NASA successfully completed the first medical evacuation from the Station, cutting the Crew-11 mission short by at least a month. By the time this article is released, the patient will be back on terra firma and having their condition assessed in California.c  This leaves just three crew members on the ISS until NASA’s Crew-12 mission can launch in early February, though it’s possible that mission’s timeline will be moved up.

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Looking At A Real Fake Raspberry Pi RP2040 Board

January 15, 2026 by 3 Comments

Since the RP2040 microcontroller is available as a stand-alone component, it’s easy enough for third parties to churn out their own variations — or outright clones of — the Raspberry Pi Pico. Thus we end up with for example AliExpress sellers offering their own versions that can be significantly cheaper than the genuine article. The ones that [electronupdate] obtained for a test and decapping session cost just $2.25 a pop.

RP2 B0 stepping imprinted on the die shot.

As can be seen in the top image, the board from AliExpress misses the Raspberry Pi logo on the silkscreen for obvious reasons, but otherwise appears to feature an identical component layout. The QSPI Flash IC is marked on the die as BY250156FS, identifying it as a Boya part.

Niggles about flash ROM quality aside, what’s perhaps most interesting about this teardown is what eagle-eyed commentators spotted on the die shot of the RP2040. Although on the MCU the laser markings identify the RP2040 as a B2 stepping, the die clearly identifies it as an ‘RP2 B0’ part, meaning B0 stepping. This can be problematic when you try to use the USB functionality due to hardware USB bugs in the B0 and B1 steppings.

As they say, caveat emptor.

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Windows? Linux? Browser? Same Executable

January 15, 2026 by 9 Comments

We’ve been aware of projects like Cosmopolitan that allow you to crank out a single executable that will run on different operating systems. [Kamila] noticed that the idea was sound, but that the executables were large and there were some limitations. So she produced a 13K file that will run under Windows, Linux, or even in a Web browser. The program itself is a simple snake game.

There seems to be little sharing between the three versions. Instead, each version is compressed and stitched together so that each platform sees what it wants to see. To accommodate Windows, the file has to start with a PE header. However, there is enough flexibility in the header that part of the stub forms a valid shell script that skips over the Windows code when running under Linux.

So, essentially, Windows skips the “garbage” in the header, which is the part that makes Linux skip the “garbage” in the front of the file.

That leaves the browser. Browsers will throw away everything before an <HTML> tag, so that’s the easy part.

Should you do this? Probably not. But if you needed to make this happen, this is a clear template for how to do it. If you want to go back to [Kamila’s] inspiration, we’ve covered Cosmopolitan and its APE format before.

Philips Kid’s Kit Revisited

January 14, 2026 by 8 Comments

[Anthony Francis-Jones], like us, has a soft spot for the educational electronic kits from days gone by. In a recent video you can see below, he shows the insides of a Philips EE08 two-transistor radio kit. This is the same kit he built a few months ago (see the second video, below).

Electronics sure look different these days. No surface mount here or even printed circuit boards. The kit had paper cards to guide the construction since the kit could be made into different circuits.

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Making Code A Hundred Times Slower With False Sharing

January 14, 2026 by 3 Comments
The cache hierarchy of the 2008 Intel Nehalem x86 architecture. (Source: Intel)
The cache hierarchy of the 2008 Intel Nehalem x86 architecture. (Source: Intel)

Writing good, performant code depends strongly on an understanding of the underlying hardware. This is especially the case in scenarios like those involving embarrassingly parallel processing, which at first glance ought to be a cakewalk. With multiple threads doing their own thing without having to nag the other threads about anything it seems highly doubtful that even a novice could screw this up. Yet as [Keifer] details in a recent video on so-called false sharing, this is actually very easy, for a variety of reasons.

With a multi-core and/or multi-processor system each core has its own local cache that contains a reflection of the current values in system RAM. If any core modifies its cached data, this automatically invalidates the other cache lines, resulting a cache miss for those cores and forcing a refresh from system RAM. This is the case even if the accessed data isn’t one that another core was going to use, with an obvious impact on performance. As cache lines are a contiguous block of data with a size and source alignment of 64 bytes on x86, it’s easy enough to get some kind of overlap here.

The worst case scenario as detailed and demonstrated using the Google Benchmark sample projects, involves a shared global data structure, with a recorded hundred times reduction in performance. Also noticeable is the impact on scaling performance, with the cache misses becoming more severe with more threads running.

A less obvious cause of performance loss here is due to memory alignment and how data fits in the cache lines. Making sure that your data is aligned in e.g. data structures can prevent more unwanted cache invalidation events. With most applications being multi-threaded these days, it’s a good thing to not only know how to diagnose false sharing issues, but also how to prevent them.

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Dad Makes Kid’s Balance Bike Into Electric Snow Trike Like A Boss

January 14, 2026 by 2 Comments

The balance bikes toddlers are rocking these days look like great fun, but not so great in the snow. Rather than see his kid’s favourite toy relegated to shed until spring, [John Boss] added electric power, and an extra wheel to make one fun-looking snow trike. Like a boss, you might say.

Physically, the trike is a delta configuration: two rear wheels and one front, though as you can see the front wheel has been turned into a ski. That’s not the most stable configuration, but by shifting the foot pegs to the front wheel and keeping the electronics down low, [John] is able to maintain a safe center of gravity. He’s also limiting the throttle so kiddo can’t go dangerously fast– indeed, the throttle control is in the rear electronics component. The kid just has a big green “go” button.

Bit-banging the throttle, combined with the weight of the kiddo up front, creates a strong tendency towards wheel-spin, but [John] fixes that with a some cleverly printed TPU paddles zip-tied to the harbor-freight wheels and tires he’s hacked into use. Those wheels are fixed to a solid axle that’s mounted to flat plate [John] had made up to attach to the bike frame. It’s all surprisingly solid, given that [John] is able to demonstrate the safety factor by going for a spin of his own. We would have done the same.

We particularly like the use of a tool battery for hot-swappable power. This isn’t the first time we’ve seen a kid’s toy get the tool battery treatment, but you aren’t limited to mobile uses. We’ve seen the ubiquitous 18V power packs in everything from fume extractors to a portable powerpack that can even charge a Tesla.

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A New Life For An Old Amplifier

January 14, 2026 by 13 Comments

An audio amplifier was once a fairly simple analogue device, but in recent decades a typical home entertainment amplifier will have expanded to include many digital functions. When these break they are often proprietary and not easy to repair, as was the case with a broken Pioneer surround-sound device given to [Boz]. It sat on the shelf for a few years until he had the idea of a jukebox for his ripped CDs, and his returning it to life with a new main board is something to behold.

Internally it’s a surprisingly modular design, meaning that the front panel with its VFD display and driver were intact and working, as were the class AB amplifier and its power supply. He had the service manual so reverse engineering was straightforward, thus out came the main board in favor of a replacement. He took the original connectors and a few other components, then designed a PCB to take them and a Raspberry Pi Pico and DAC. With appropriate MMBASIC firmware it looks as though it was originally made this way, a sense heightened by a look at the motherboard inside (ignoring a couple of bodges).

We like seeing projects like this one which revive broken devices, and this one is particularly special quality wise. We’re more used to seeing it with gaming hardware though.