Venus Climate Orbiter Akatsuki’s Mission Has Ended

September 20, 2025 by 5 Comments

Japan’s Venus Climate Orbiter Akatsuki was launched on May 21, 2010, and started its active mission in 2015 after an initial orbital insertion failure. Since that time, Akatsuki has continuously observed Venus from orbit until issues began to crop up in 2024 when contact was lost in April of that year due to attitude control issues. Japan’s space agency, JAXA, has now announced that the mission has officially ended on September 18, 2025, after a period of trying to coax the spacecraft back into some level of functionality again.

The Akatsuki spacecraft in 2010 before its launch. (Credit: JAXA)
The Akatsuki spacecraft in 2010 before its launch. (Credit: JAXA)

The Akatsuki spacecraft had six instruments, consisting of cameras covering the visible spectrum, ultraviolet and infrared spectra, as well as an oscillator for radio occultation experiments.

All primary mission goals were successfully completed in April of 2018, but engineers determined Akatsuki was capable of lasting at least another few years. This puts it well past its original design lifespan, and has provided us with much more scientific data than we could have hoped for.

Unfortunately, the shutdown of Akatsuki represents the end of the last active Venus mission, with much uncertainty surrounding any potential upcoming mission to Earth’s near-twin planet. The next potential mission is the Venus Life Finder, as an atmospheric mission penciled in for a 2026 launch. It would take at least until 2028 for a potential orbiter mission to launch, so for the foreseeable future Venus will be left alone, without its artificial moon that has kept it company for a decade.

Regretfully: $3,000 Worth Of Raspberry Pi Boards

September 20, 2025 by 53 Comments

We feel for [Jeff Geerling]. He spent a lot of effort building an AI cluster out of Raspberry PI boards and $3,000 later, he’s a bit regretful. As you can see in the video below, it is a neat build. As Jeff points out, it is relatively low power and dense. But dollar for dollar, it isn’t much of a supercomputer.

Of course, the most obvious thing is that there’s plenty of CPU, but no GPU. We can sympathize, too, with the fact that he had to strip it down twice and rebuild it for a total of three rebuilds. One time, he decided to homogenize the SSDs for each board. The second time was to affix the heatsinks. It is always something.

With ten “blades” — otherwise known as compute modules — the plucky little computer turned in about 325 gigaflops on tests. That sounds pretty good, but a Framework Desktop x4 manages 1,180 gigaflops. What’s more is that the Framework turned out cheaper per gigaflop, too. Each dollar bought about 110 megaflops for the Pis, but about 140 for the Framework.

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Computer Has One Instruction, Many Transistors

September 20, 2025 by 22 Comments

There’s always some debate around what style of architecture is best for certain computing applications, with some on the RISC side citing performance per watt and some on the CISC side citing performance per line of code. But when looking at instruction sets it’s actually possible to eliminate every instruction except one and still have a working, Turing-complete computer. This instruction is called subleq or “subtract and branch if less-than or equal to zero“. [Michael] has built a computer that does this out of discrete components from scratch.

We’ll save a lot of the details of the computer science for [Michael] or others to explain, but at its core this is a computer running with a 1 kHz clock with around 700 transistors total. Since the goal of a single-instruction computer like this is simplicity, the tradeoff is that many more instructions need to be executed for equivalent operations. For this computer it takes six clock cycles to execute one instruction, for a total of about 170 instructions per second. [Michael] also created an assembler for this computer, so with an LCD screen connected and mapped to memory he can write and execute a simple “hello world” program just like any other computer.

[Michael] does note that since he was building this from Logisim directly he doesn’t have a circuit schematic, but due to some intermittent wiring issues might have something in the future if he decides to make PCBs for this instead of using wire on a cardboard substrate. There’s plenty of other information on his GitHub page though. It’s a unique project that gets to the core of what’s truly needed for a working computer. There are a few programming languages out there that are built on a similar idea.

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“Simplest” Oscilloscope Is A Cunning Vector Display

September 20, 2025 by 18 Comments

Superlatives are tricky things. [mircemk]’s guide “How to make Simplest ever Oscilloscope Clock” falls into that category. It’s that word, simplest. Certainly, this is an oscilloscope clock, and a nice one. But is it simple?

There’s a nice oscilloscope circuit with a cute 2″ 5LO38I CRT and EF80 tubes for horizontal and vertical deflection that we’d say is pretty simple. (It’s based on an earlier DIY oscilloscope project [mircemk] did.) The bill of materials is remarkably sparse– but it’s modules that do it. One entry is a DC-DC step up supply to get the needed HV. Another is a LM317 to get 6.3 V to heat the tubes. The modules make for a very simple BOM, but on another level, there’s quite a bit of complex engineering in those little modules.

When we get to the “clock” part of the oscilloscope clock, that quandary goes into overdrive. There’s only one line on the BOM, so that’s very simple. On the other hand, it’s an ESP32. Depending on your perspective, that’s not simple at all. It’s a microcomputer, or at least something that can play at emulating one.

Oh, in the ways that matter to a maker — parts count, time, and effort, this oscilloscope clock is very simple. The fact that its actually a vector display for a powerful little micro just adds to the versatility of the build. We absolutely love it, to be honest. Still, the idea that you can have millions of transistors in a simple project — never mind the “simplest ever” — well, it just seems weird on some level when you think about it.

It all comes back to what counts as “simple”. If we’re taking lines on a BOM, arguably this would be even simpler if you used an existing oscilloscope. 

Fnirsi IPS3608: A Bench Power Supply With Serious Flaws

September 20, 2025 by 16 Comments

Fnirsi is one of those brands that seem to pop up more and more often, usually for portable oscilloscopes and kin. Their IPS3608 bench power supply is a bit of a departure from that, offering a mains-powered PSU that can deliver up to 36 VDC and 8 A in a fairly compact, metal enclosure. Recently [Joftec] purchased one of these units in order to review it and ended up finding a few worrying flaws in the process.

One of the claims made on the product page is that it is ‘much more intelligent than traditional power supplies’, which is quite something to start off with. The visual impression of this PSU is that it’s somewhat compromised already, with no earth point on the front next to the positive and negative banana plug points, along with a tilting screen that has trouble staying put. The USB-C and -A ports on the front support USB-PD 3.0 and a range of fast charge protocols

The ‘intelligence’ claim seems to come mostly from the rather extensive user interface, including a graphing function. Where things begin to fall apart is when the unit locks up during load testing presumably due to an overheating event. After hooking up an oscilloscope, the ripple at 1 VDC was determined to be about 200 mV peak-to-peak at 91 kHz. Ripple increased at higher voltages, belying the ’10 mV ultra-low ripple’ claim.

A quick teardown revealed the cause for the most egregious flaw of the unit struggling to maintain even 144 Watt output: a very undersized heatsink on the SMPS board. The retention issues with the tilting issue seemed to be due to a design choice that prevents the screen from rotating without breaking plastic. While this latter issue could be fixed, the buggy firmware and high ripple on the DC output make this €124 ‘285 Watt’ into a hard pass.

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Fire Extinguishers, Optical Density Ratings And Safely Using Home Lasers

September 19, 2025 by 25 Comments
Ski goggle type laser safety lenses may look dorky, but they leave no gaps and fit around glasses. (Credit: FauxHammer, YouTube)
Ski goggle type laser safety lenses may look dorky, but they leave no gaps and fit around glasses. (Credit: FauxHammer, YouTube)

After [Ross] from FauxHammer miniature model fame got lured into reviewing laser engravers and similar via the Bambu Lab H2D’s laser module, he found himself getting slightly nervous about the whole ‘safety’ aspect of these lasers. After all, lasers can not only light stuff on fire, but it’s a well-known fact that even reflected laser light can be sufficient to cause permanent damage to your retinas. Or worse.

Since your eyes generally do not regenerate, it makes sense to get caught up on laser safety before turning on one of those plentiful-and-increasingly-affordable home laser systems for engraving and/or cutting.

While the issue of stuff catching on fire is readily solved by having a good CO2 extinguisher – and plan B options – at the ready, for safety glasses it’s significantly more complex. There’s not just the issue of finding glasses that block the wavelength of the laser system that you are using, but also with the right optical density (OD) rating. Every mm of the safety lens material can attenuate a certain amount of laser light at the given wavelength, so the OD rating of your laser safety goggles need to match the laser’s power output level, or you might be living with a false sense of security.

Finally, there is the issue of the smoke and fumes produced by these lasers as they obliterate the target material. Much of what is in this smoke you do not want to breathe in, even ignoring long-term dust and VOC exposure issues, so having a solid fume extraction setup and PPE as necessary are absolute necessities. As [Ross] puts it, you don’t want to breathe in the smell of regret today, for your future self to reflect on a decade from now.

Work safe, work smart, don’t become the subject of a laser safety PSA.

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BCacheFS Is Now A DKMS Module After Exile From The Linux Kernel

September 19, 2025 by 46 Comments

It’s been a tense few months for users of the BCacheFS filesystem, as amidst the occasional terse arguments and flowery self-praise on the Linux Kernel mailing list the future of this filesystem within the Linux kernel hung very much in the balance. After some initial confusion about what ‘externally maintained’ means in Linux parlance, it’s now clear that this means that BCacheFS has effectively been kicked out of the kernel as [Linus] promised and will ship as a DKMS module instead. The gory details of this change are discussed in a recent video by [Brodie Robertson].

We covered the BCacheFS controversy in the Linux world a few months ago, amidst reports of data loss and filesystem corruption among its users. Its lead developer, [Kent Overstreet], came to blows with [Linus Torvalds] on the LKML after [Kent] insisted on repeatedly pushing new features into kernel release candidate branches along with rather haughty statements on why he should be able to do this.

To make a long story short, [Linus] didn’t like this and froze BCacheFS support in the current kernel release with all future in-kernel development ceased. Distributions like SuSE have initially said that will disable BCacheFS starting in kernel version 6.17, meaning that users of BCacheFS may now have to install the DKMS module themselves. Some distributions like Arch are likely to include this DKMS module by default, which is something you want to check if you use this filesystem.

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