Are your Eurorack modules too crowded? Sick of your patch cables making it hard to twiddle your knobs? Then you might be very interested in the new Euroknob, the knob that sports a hidden patch cable jack.

Honestly, when we first saw the Euroknob demo board, we thought [Mitxela] had gone a little off the rails. It looks like nothing more than a PCB-mount potentiometer or perhaps an encoder with a knob attached. Twist the knob and a row of LEDs on the board light up in sequence. Nice, but not exactly what we’re used to seeing from him. But then he popped the knob off the board, revealing that what we thought was the pot body is actually a 3.5-mm audio jack, and that the knob was attached to a mating plug that acts as an axle.

The kicker is that underneath the audio jack is an AS5600 magnetic encoder, and hidden in a slot milled in the tip of the audio jack is a tiny magnet. Pop the knob into the jack, give it a twist, and you’ve got manual control of your module. Take the knob out, plug in a patch cable, and you can let a control voltage from another module do the job. Genius!

To make it all work mechanically, [Mitxela] had to sandwich a spacer board on top of the main PCB. The spacer has a large cutout to make room for the sensor chip so the magnet can rotate without hitting anything. He also added a CH32V003 to run the encoder and drive the LEDs to provide feedback for the knob-jack. The video below has a brief demo.

This is just a proof of concept, to be sure, but it’s still pretty slick. Almost as slick as [Mitxela]’s recent fluid-motion simulation pendant, or his dual-wielding soldering irons.

Looks like the Simpsons had it right again, now that an Australian radio station has been caught using an AI-generated DJ for their midday slot. Station CADA, a Sydney-based broadcaster that’s part of the Australian Radio Network, revealed that “Workdays with Thy” isn’t actually hosted by a person; rather, “Thy” is a generative AI text-to-speech system that has been on the air since November. An actual employee of the ARN finance department was used for Thy’s voice model and her headshot, which adds a bit to the creepy factor.

The discovery that they’ve been listening to a bot for months apparently has Thy’s fans in an uproar, although we suspect that the media doing the reporting is probably more exercised about this than the general public. Radio stations have used robo-jocks for the midday slot for ages, albeit using actual human DJs to record patter to play between tunes and commercials. Anyone paying attention over the last few years probably shouldn’t be surprised by this development, and we suspect similar disclosures will be forthcoming across the industry now that the cat’s out of the bag.

Also from the world of robotics, albeit the hardware kind, is this excellent essay from Brian Potter over at Construction Physics about the sad state of manual dexterity in humanoid robots. The whole article is worth reading, not least for the link to a rogue’s gallery of the current crop of humanoid robots, but briefly, the essay contends that while humanoid robots do a pretty good job of navigating in the world, their ability to do even the simplest tasks is somewhat wanting.

Brian’s example of unwrapping and applying a Band-Aid, a task that any toddler can handle, as being unimaginably difficult for any current robot to handle is quite apt. He attributes the gap in abilities between gross movements and fine motor control partly to hardware and partly to software. We think the blame skews more to the hardware side; while the legs and torso of the typical humanoid robot offer a lot of real estate for powerful actuators, squeezing that much equipment into a hand approximately the size of a human’s is a tall order. These problems will likely be overcome, of course, and when they do, Brian’s helpful list of “Dexterity Evals” or something similar will act as a sort of Turing test for robot dexterity. Although the day a humanoid robot can start a new roll of toilet paper without tearing the first sheet is the day we head for the woods.

We recently did a story on the use of nitrogen-vacancy diamonds as magnetic sensors, which we found really exciting because it’s about the simplest way we’ve seen to play with quantum physics at home. After that story ran, eagle-eyed reader Kealan noticed that Brian over at the “Real Engineering” channel on YouTube had recently run a video on anti-submarine warfare, which includes the uses of similar quantum magnetometers to detect submarines. The magnetometers in the video are based on the Zeeman effect and use laser-pumped helium atoms to detect tiny variations in the Earth’s magnetic field due to large ferrous objects like submarines. Pretty cool video; check it out.

And finally, if you have the slightest interest in civil engineering you’ve got to check out Animagraff’s recent 3D tour of the insides of Hoover Dam. If you thought a dam was just a big, boring block of concrete dumped in the middle of a river, think again. The video is incredibly detailed and starts with accurate 3D models of Black Canyon before the dam was built. Every single detail of the dam is shown, with the “X-ray views” of the dam with the surrounding rock taken away being our favorite bit — reminds us a bit of the book Underground by David Macaulay. But at the end of the day, it’s the enormity of Hoover Dam that really comes across in this video. The way that the structure dwarfs the human-for-scale included in almost every sequence is hard to express — megalophobics, beware. We were also floored by just how much machinery is buried in all that concrete. Sure, we knew about the generators, but the gates on the intake towers and the way the spillways work were news to us. Highly recommended.

It’s human nature to look at the technological achievements of the ancients — you know, anything before the 1990s — and marvel at how they were able to achieve precision results in such benighted times. How could anyone create a complicated mechanism without the aid of CNC machining and computer-aided design tools? Clearly, it was aliens.

Or, as [Chris] from Click Spring demonstrates by creating precision nesting thin-wall tubing, it was human beings running the same wetware as what’s running between our ears but with a lot more patience and ingenuity. It’s part of his series of experiments into how the craftsmen of antiquity made complicated devices like the Antikythera mechanism with simple tools. He starts by cleaning up roughly wrought brass rods on his hand-powered lathe, followed by drilling and reaming to create three tubes with incremental precision bores. He then creates matching pistons for each tube, with an almost gas-tight enough fit right off the lathe.

Getting the piston fit to true gas-tight precision came next, by lapping with a jeweler’s rouge made from iron swarf recovered from the bench. Allowed to rust and ground to a paste using a mortar and pestle, the red iron oxide mixed with olive oil made a dandy fine abrasive, perfect for polishing the metal to a high gloss finish. Making the set of tubes concentric required truing up the bores on the lathe, starting with the inner-most tube and adding the next-largest tube once the outer diameter was lapped to spec.

Easy? Not by a long shot! It looks like a tedious job that we suspect was given to the apprentice while the master worked on more interesting chores. But clearly, it was possible to achieve precision challenging today’s most exacting needs with nothing but the simplest tools and plenty of skill.

It’s amazing how quickly medical science made radiography one of its main diagnostic tools. Medicine had barely emerged from its Dark Age of bloodletting and the four humours when X-rays were discovered, and the realization that the internal structure of our bodies could cast shadows of this mysterious “X-Light” opened up diagnostic possibilities that went far beyond the educated guesswork and exploratory surgery doctors had relied on for centuries.

The problem is, X-rays are one of those things that you can’t see, feel, or smell, at least mostly; X-rays cause visible artifacts in some people’s eyes, and the pencil-thin beam of a CT scanner can create a distinct smell of ozone when it passes through the nasal cavity — ask me how I know. But to be diagnostically useful, the varying intensities created by X-rays passing through living tissue need to be translated into an image. We’ve already looked at how X-rays are produced, so now it’s time to take a look at how X-rays are detected and turned into medical miracles.

Taking Pictures

For over a century, photographic film was the dominant way to detect medical X-rays. In fact, years before Wilhelm Conrad Röntgen’s first systematic study of X-rays in 1895, fogged photographic plates during experiments with a Crooke’s tube were among the first indications of their existence. But it wasn’t until Röntgen convinced his wife to hold her hand between one of his tubes and a photographic plate to create the first intentional medical X-ray that the full potential of radiography could be realized.

The chemical mechanism that makes photographic film sensitive to X-rays is essentially the same as the process that makes light photography possible. X-ray film is made by depositing a thin layer of photographic emulsion on a transparent substrate, originally celluloid but later polyester. The emulsion is a mixture of high-grade gelatin, a natural polymer derived from animal connective tissue, and silver halide crystals. Incident X-ray photons ionize the halogens, creating an excess of electrons within the crystals to reduce the silver halide to atomic silver. This creates a latent image on the film that is developed by chemically converting sensitized silver halide crystals to metallic silver grains and removing all the unsensitized crystals.

Other than in the earliest days of medical radiography, direct X-ray imaging onto photographic emulsions was rare. While photographic emulsions can be exposed by X-rays, it takes a lot of energy to get a good image with proper contrast, especially on soft tissues. This became a problem as more was learned about the dangers of exposure to ionizing radiation, leading to the development of screen-film radiography.

In screen-film radiography, X-rays passing through the patient’s tissues are converted to light by one or more intensifying screens. These screens are made from plastic sheets coated with a phosphorescent material that glows when exposed to X-rays. Calcium tungstate was common back in the day, but rare earth phosphors like gadolinium oxysulfate became more popular over time. Intensifying screens were attached to the front and back covers of light-proof cassettes, with double-emulsion film sandwiched between them; when exposed to X-rays, the screens would glow briefly and expose the film.

By turning one incident X-ray photon into thousands or millions of visible light photons, intensifying screens greatly reduce the dose of radiation needed to create diagnostically useful images. That’s not without its costs, though, as the phosphors tend to spread out each X-ray photon across a physically larger area. This results in a loss of resolution in the image, which in most cases is an acceptable trade-off. When more resolution is needed, single-screen cassettes can be used with one-sided emulsion films, at the cost of increasing the X-ray dose.

Wiggle Those Toes

Intensifying screens aren’t the only place where phosphors are used to detect X-rays. Early on in the history of radiography, doctors realized that while static images were useful, continuous images of body structures in action would be a fantastic diagnostic tool. Originally, fluoroscopy was performed directly, with the radiologist viewing images created by X-rays passing through the patient onto a phosphor-covered glass screen. This required an X-ray tube engineered to operate with a higher duty cycle than radiographic tubes and had the dual disadvantages of much higher doses for the patient and the need for the doctor to be directly in the line of fire of the X-rays. Cataracts were enough of an occupational hazard for radiologists that safety glasses using leaded glass lenses were a common accessory.

One ill-advised spin-off of medical fluoroscopy was the shoe-fitting fluoroscopes that started popping up in shoe stores in the 1920s. Customers would stick their feet inside the machine and peer at a fluorescent screen to see how well their new shoes fit. It was probably not terribly dangerous for the once-a-year shoe shopper, but pity the shoe salesman who had to peer directly into a poorly regulated X-ray beam eight hours a day to show every Little Johnny’s mother how well his new Buster Browns fit.

As technology improved, image intensifiers replaced direct screens in fluoroscopy suites. Image intensifiers were vacuum tubes with a large input window coated with a fluorescent material such as zinc-cadmium sulfide or sodium-cesium iodide. The phosphors convert X-rays passing through the patient to visible light photons, which are immediately converted to photoelectrons by a photocathode made of cesium and antimony. The electrons are focused by coils and accelerated across the image intensifier tube by a high-voltage field on a cylindrical anode. The electrons pass through the anode and strike a phosphor-covered output screen, which is much smaller in diameter than the input screen. Incident X-ray photons are greatly amplified by the image intensifier, making a brighter image with a lower dose of radiation.

Originally, the radiologist viewed the output screen using a microscope, which at least put a little more hardware between his or her eyeball and the X-ray source. Later, mirrors and lenses were added to project the image onto a screen, moving the doctor’s head out of the direct line of fire. Later still, analog TV cameras were added to the optical path so the images could be displayed on high-resolution CRT monitors in the fluoroscopy suite. Eventually, digital cameras and advanced digital signal processing were introduced, greatly streamlining the workflow for the radiologist and technologists alike.

Get To The Point

So far, all the detection methods we’ve discussed fall under the general category of planar detectors, in that they capture an entire 2D shadow of the X-ray beam after having passed through the patient. While that’s certainly useful, there are cases where the dose from a single, well-defined volume of tissue is needed. This is where point detectors come into play.

In medical X-ray equipment, point detectors often rely on some of the same gas-discharge technology that DIYers use to build radiation detectors at home. Geiger tubes and ionization chambers measure the current created when X-rays ionize a low-pressure gas inside an electric field. Geiger tubes generally use a much higher voltage than ionization chambers, and tend to be used more for radiological safety, especially in nuclear medicine applications, where radioisotopes are used to diagnose and treat diseases. Ionization chambers, on the other hand, were often used as a sort of autoexposure control for conventional radiography. Tubes were placed behind the film cassette holders in the exam tables of X-ray suites and wired into the control panels of the X-ray generators. When enough radiation had passed through the patient, the film, and the cassette into the ion chamber to yield a correct exposure, the generator would shut off the X-ray beam.

Another kind of point detector for X-rays and other kinds of radiation is the scintillation counter. These use a crystal, often cesium iodide or sodium iodide doped with thallium, that releases a few visible light photons when it absorbs ionizing radiation. The faint pulse of light is greatly amplified by one or more photomultiplier tubes, creating a pulse of current proportional to the amount of radiation. Nuclear medicine studies use a device called a gamma camera, which has a hexagonal array of PM tubes positioned behind a single large crystal. A patient is injected with a radioisotope such as the gamma-emitting technetium-99, which accumulates mainly in the bones. Gamma rays emitted are collected by the gamma camera, which derives positional information from the differing times of arrival and relative intensity of the light pulse at the PM tubes, slowly building a ghostly skeletal map of the patient by measuring where the ⁹⁹Tc accumulated.

Going Digital

Despite dominating the industry for so long, the days of traditional film-based radiography were clearly numbered once solid-state image sensors began appearing in the 1980s. While it was reliable and gave excellent results, film development required a lot of infrastructure and expense, and resulted in bulky films that required a lot of space to store. The savings from doing away with all the trappings of film-based radiography, including the darkrooms, automatic film processors, chemicals, silver recycling, and often hundreds of expensive film cassettes, is largely what drove the move to digital radiography.

After briefly flirting with phosphor plate radiography, where a sensitized phosphor-coated plate was exposed to X-rays and then “developed” by a special scanner before being recharged for the next use, radiology departments embraced solid-state sensors and fully digital image capture and storage. Solid-state sensors come in two flavors: indirect and direct. Indirect sensor systems use a large matrix of photodiodes on amorphous silicon to measure the light given off by a scintillation layer directly above it. It’s basically the same thing as a film cassette with intensifying screens, but without the film.

Direct sensors, on the other hand, don’t rely on converting the X-ray into light. Rather, a large flat selenium photoconductor is used; X-rays absorbed by the selenium cause electron-hole pairs to form, which migrate to a matrix of fine electrodes on the underside of the sensor. The current across each pixel is proportional to the amount measured to the amount of radiation received, and can be read pixel-by-pixel to build up a digital image.

Building a Commodore 64 is among the easier projects for retrocomputing fans to tackle. That’s because the C64’s core chipset does most of the heavy lifting; source those and you’re probably 80% of the way there. But what if you can’t find those chips, or if you want more of a challenge than plugging and chugging? Are you out of luck?

Hardly. The video below from [DrMattRegan] is the first in a series on his scratch-built C64 that doesn’t use the core chipset, and it looks pretty promising. This video concentrates on building a replacement for the 6502 microprocessor — actually the 6510, but close enough — using just a couple of EPROMs, some SRAM chips, and a few standard logic chips to glue everything together. He uses the EPROMs as a “rulebook” that contains the code to emulate the 6502 — derived from his earlier Turing 6502 project — and the SRAM chips as a “notebook” for scratch memory and registers to make a Turing-complete random access machine.

[DrMatt] has made good progress so far, with the core 6502 CPU built on a PCB and able to run the Apple II version of Pac-Man as a benchmark. We’re looking forward to the rest of this series, but in the meantime, a look back at his VIC-less VIC-20 project might be informative.

Thanks to [Clint] for the tip.

We appear to be edging ever closer to a solid statement of “We are not alone” in the universe with this week’s announcement of the detection of biosignatures in the atmosphere of exoplanet K2-18b. The planet, which is 124 light-years away, has been the focus of much attention since it was discovered in 2015 using the Kepler space telescope because it lies in the habitable zone around its red-dwarf star. Initial observations with Hubble indicated the presence of water vapor, and follow-up investigations using the James Webb Space Telescope detected all sorts of goodies in the atmosphere, including carbon dioxide and methane. But more recently, JWST saw signs of dimethyl sulfide (DMS) and dimethyl disulfide (DMDS), organic molecules which, on Earth, are strongly associated with biological processes in marine bacteria and phytoplankton.

The team analyzing the JWST data says that the data is currently pretty good, with a statistical significance of 99.7%. That’s a three-sigma result, and while it’s promising, it’s not quite good enough to seal the deal that life evolved more than once in the universe. If further JWST observations manage to firm that up to five sigma, it’ll be the most important scientific result of all time. To our way of thinking, it would be much more significant than finding evidence of ancient or even current life in our solar system, since cross-contamination is so easy in the relatively cozy confines of the Sun’s gravity well. K2-18b is far enough away from our system as to make that virtually impossible, and that would say a lot about the universality of biochemical evolution. It could also provide an answer to the Fermi Paradox, since it could indicate that the galaxy is actually teeming with life but under conditions that make it difficult to evolve into species capable of making detectable techno-signatures. It’s hard to build a radio or a rocket when you live on a high-g water world, after all.

Closer to home, there’s speculation that the famous Antikythera mechanism may not have worked at all in its heyday. According to researchers from Universidad Nacional de Mar del Plata in Argentina, “the world’s first analog computer” could not have worked due to the accumulated mechanical error of its gears. They blame this on the shape of the gear teeth, which appear triangular on CT scans of the mechanism, and which they seem to attribute to manufacturing defects. Given the 20-odd centuries the brass-and-iron device spent at the bottom of the Aegean Sea and the potential for artifacts in CT scans, we’re not sure it’s safe to pin the suboptimal shape of the gear teeth on the maker of the mechanism. They also seem to call into question the ability of 1st-century BCE craftsmen to construct a mechanism with sufficient precision to serve as a useful astronomical calculator, a position that Chris from Clickspring has been putting the lie to with his ongoing effort to reproduce the Antikythera mechanism using ancient tools and materials. We’re keen to hear what he has to say about this issue.

Speaking of questionable scientific papers, have you heard about “vegetative electron microscopy”? It’s all the rage, having been mentioned in at least 22 scientific papers recently, even though no such technique exists. Or rather, it didn’t exist until around 2017, when it popped up in a couple of Iranian scientific papers. How it came into being is a bit of a mystery, but it may have started with faulty scans of a paper from the 1950s, which had the terms “vegetative” and “electron microscopy” printed in different columns but directly across from each other. That somehow led to the terms getting glued together, possibly in one of those Iranian papers because the Farsi spelling of “vegetative” is very similar to “scanning,” a much more sensible prefix to “electron microscopy.” Once the nonsense term was created, it propagated into subsequent papers of dubious scientific provenance by authors who didn’t bother to check their references, or perhaps never existed in the first place. The wonders of our AI world never cease to amaze.

And finally, from the heart of Silicon Valley comes a tale of cyber hijinks as several crosswalks were hacked to taunt everyone’s favorite billionaires. Twelve Palo Alto crosswalks were targeted by persons unknown, who somehow managed to gain access to the voice announcement system in the crosswalks and replaced the normally helpful voice messages with deep-fake audio of Elon Musk and Mark Zuckerberg saying ridiculous but plausible things. Redwood City and Menlo Park crosswalks may have also been attacked, and soulless city officials responded by disabling the voice feature. We get why they had to do it, but as cyberattacks go, this one seems pretty harmless.

How it started: a simple repair job on a Roland drum machine. How it ended: a scratch-built FM drum synth module that’s completely analog, and completely cool.

[Moritz Klein]’s journey down the analog drum machine rabbit hole started with a Roland TR-909, a hybrid drum machine from the mid-80s that combined sampled sounds with analog synthesis. The unit [Moritz] picked up was having trouble with the decay on the kick drum, so he spread out the gloriously detailed schematic and got to work. He breadboarded a few sections of the kick drum circuit to aid troubleshooting, but one thing led to another and he was soon in new territory.

The video below is on the longish side, with the first third or so dedicated to recreating the circuits used to create the 909’s iconic sound, slightly modifying some of them to simplify construction. Like the schematic that started the whole thing, this section of the video is jam-packed with goodness, too much to detail here. But a few of the gems that caught our eye were the voltage-controlled amplifier (VCA) circuit that seems to make appearances in multiple places in the circuit, and the dead-simple wave-shaper circuit, which takes some of the harmonics out of the triangle wave oscillator’s output with just a couple of diodes and some resistors.

Once the 909’s kick and toms section had been breadboarded, [Moritz] turned his attention to adding something Roland hadn’t included: frequency modulation. He did this by adding a second, lower-frequency voltage-controlled oscillator (VCO) and using that to modulate the drum section. That resulted in a weird, metallic sound that can be tuned to imitate anything from a steel drum to a bell. He also added a hi-hat and cymbal section by mixing the square wave outputs on the VCOs through a funky XOR gate made from discrete components and a high-pass filter.

There’s a lot of information packed into this video, and by breaking everything down into small, simple blocks, [Moritz] makes it easy to understand analog synths and the circuits behind them.

How would you go about determining absolute zero? Intuitively, it seems like you’d need some complicated physics setup with lasers and maybe some liquid helium. But as it turns out, all you need is some simple lab glassware and a heat gun. And a laser, of course.

To be clear, the method that [Markus Bindhammer] describes in the video below is only an estimation of absolute zero via Charles’s Law, which describes how gases expand when heated. To gather the needed data, [Marb] used a 50-ml glass syringe mounted horizontally on a stand and fitted with a thermocouple. Across from the plunger of the syringe he placed a VL6180 laser time-of-flight sensor, to measure the displacement of the plunger as the air within it expands.

Data from the TOF sensor and the thermocouple were recorded by a microcontroller as the air inside the syringe was gently heated. Plotting the volume of the gas versus the temperature results shows a nicely linear relationship, and the linear regression can be used to calculate the temperature at which the volume of the gas would be zero. The result: -268.82°C, or only about four degrees off from the accepted value of -273.15°. Not too shabby.

[Marb] has been on a tear lately with science projects like these; check out his open-source blood glucose measurement method or his all-in-one electrochemistry lab.

With vector network analyzers, the commercial offerings seem to come in two flavors: relatively inexpensive but limited capabilities, and full-featured but scary expensive. There doesn’t seem to be much middle ground, especially if you want something that performs well in the microwave bands.

Unless, of course, you build your own vector network analyzer (VNA). That’s what [Henrik Forsten] did, and we’ve got to say we’re even more impressed by the results than we were with his earlier effort. That version was not without its problems, and fixing them was very much on the list of goals for this build. Keeping the build affordable was also key, which resulted in some design compromises while still meeting [Henrik]’s measurement requirements.

The Bill of Materials includes dual-channel broadband RF mixer chips, high-speed 12-bit ADCs, and a fast FPGA to handle the torrent of data and run the digital signal processing functions. The custom six-layer PCB is on the large side and includes large cutouts for the directional couplers, which use short lengths of stripped coaxial cable lined with ferrite rings. To properly isolate signals between stages, [Henrik] sandwiched the PCB between a two-piece aluminum enclosure. Wisely, he printed a prototype enclosure and lined it with aluminum foil to test for fit and function before committing to milling the final version. He did note some leakage around the SMA connectors, but a few RF gaskets made from scraps of foil and solder braid did the trick.

This is a pretty slick build, especially considering he managed to keep the price tag at a very reasonable $300. It’s more expensive than the popular NanoVNA or its clones, but it seems like quite a bargain considering its capabilities.

We’re probably all familiar with the Hall Effect, at least to the extent that it can be used to make solid-state sensors for magnetic fields. It’s a cool bit of applied physics, but there are other ways to sense magnetic fields, including leveraging the weird world of quantum physics with this diamond, laser, and microwave open-source sensor.

Having never heard of quantum sensors before, we took the plunge and read up on the topic using some of the material provided by [Mark C] and his colleagues at Quantum Village. The gist of it seems to be that certain lab-grown diamonds can be manufactured with impurities such as nitrogen, which disrupt the normally very orderly lattice of carbon atoms and create a “nitrogen vacancy,” small pockets within the diamond with extra electrons. Shining a green laser on N-V diamonds can stimulate those electrons to jump up to higher energy states, releasing red light when they return to the ground state. Turning this into a sensor involves sweeping the N-V diamond with microwave energy in the presence of a magnetic field, which modifies which spin states of the electrons and hence how much red light is emitted.

Building a practical version of this quantum sensor isn’t as difficult as it sounds. The trickiest part seems to be building the diamond assembly, which has the N-V diamond — about the size of a grain of sand and actually not that expensive — potted in clear epoxy along with a loop of copper wire for the microwave antenna, a photodiode, and a small fleck of red filter material. The electronics primarily consist of an ADF4531 phase-locked loop RF signal generator and a 40-dB RF amplifier to generate the microwave signals, a green laser diode module, and an ESP32 dev board.

All the design files and firmware have been open-sourced, and everything about the build seems quite approachable. The write-up emphasizes Quantum Village’s desire to make this quantum technology’s “Apple II moment,” which we heartily endorse. We’ve seen N-V sensors detailed before, but this project might make it easier to play with quantum physics at home.

It’s been a while since we’ve dunked on an autonomous taxi foul-up, mainly because it seemed for a while there that most of the companies field testing driverless ride-sharing services had either ceased operation or curtailed them significantly. But that appears not to be the case after a Waymo robotaxi got stuck in a Chick-fil-A drive-through. The incident occurred at the chicken giant’s Santa Monica, California location at about 9:30 at night, when the autonomous Jaguar got stuck after dropping off a passenger in the parking lot. The car apparently tried to use the drive-through lane to execute a multi-point turn but ended up across the entrance, blocking other vehicles seeking their late-evening chicken fix. The drive-through-only restaurant ended up closing for a short time while Waymo figured out how to get the vehicle moving again.

To be fair, drive-through lanes are challenging even for experienced drivers. Lanes are often narrow, curve radii are sometimes tighter than a large vehicle can negotiate smoothly, and the task-switching involved with transitioning from driver to customer can lead to mistakes. Drive-throughs almost seem engineered to make tempers flare, especially at restaurants where hangry drivers are likely to act out at the slightest delay. This is probably doubly so when drivers are stuck behind a driverless car, completely eliminating even the minimal decency that would likely be extended to a human driver who got themselves in a pickle. If people are willing to honk at and curse out the proverbial little old lady from Pasadena, they’re very unlikely to cooperate with a robotaxi and give it the room it needs to maneuver out of a tight spot. Perhaps that argues for a change in programming that accounts for real-world driving experiences as well as the letter of the law.

The big news from space this week was the private Fram2 mission, which took an all-civilian crew on the world’s first crewed polar flight. The four-person crew took off from Florida in a SpaceX Crew Dragon and rather than heading east towards Africa, took off due north and entered a retrograde orbit at 90° inclination, beating the previous record of 65° inclination by Valentina Tereshkova aboard Vostok 6 back in 1963. The Fram2 team managed a couple of other firsts, from the first medical X-rays taken in space to the first amateur radio contacts made from the Dragon.

It’s been a while, but Bill “The Engineer Guy” Hammack is back with a new video extolling the wonders of plastic soda bottles. If you think that’s a subject too mundane to hold your interest, then you’ve never seen Bill at work. The amount of engineering that goes into creating a container that can stand up to its pressurized content while being able to be handled both by automation machines at the bottling plant and by thirsty consumers is a lesson in design brilliance. Bill explains the whole blow-molding process, amazingly using what looks like an actual Coca-Cola production mold. We would have thought such IP would be fiercely protected, but such is Bill’s clout, we guess. The video is also a little trip down memory lane for some of us, as Bill shows off both the two-piece 2-liter bottles that used to grace store shelves and the ponderous glass versions that predated those. Also interesting is the look at the differences between hot-fill bottles and soda bottles, which we never appreciated before.

And finally, if you’ve ever been confused by which logical fallacy is clouding your thinking, why not turn to the most famous fictional logician of all time to clarify things? “Star Trek Logical Reasoning” is a YouTube series by CHDanhauser that uses clips from the Star Trek animated series to illustrate nearly 70 logical fallacies. Each video is quite short, with most featuring Commander Spock eavesdropping on the conversations of his less-logical shipmates and pointing out the flaws in their logic. Luckily, the 23rd century seems to have no equivalent of human(oid) resources, because Spock’s logical interventions are somewhat toxic by today’s standards, but that’s a small price to pay for getting your logical ducks in a row.

Sick of raiding old TVs and CRT monitors for flyback transformers to feed your high-voltage addiction? Never fear; if you’re careful, a 3D-printed flyback might be just the thing you’re looking for.

To be fair, it’s pretty easy to come by new flyback transformers, so building your own isn’t strictly necessary. But [SciTubeHD] was in the market for a particularly large flyback, in a good-natured effort to displace [Jay Bowles] from his lofty perch atop the flyback heap. And it’s also true that this project isn’t entirely 3D-printed, as the split core of the transformer was sourced commercially. The secondary coil, though, was where most of the effort went, with a secondary form made from multiple snap-together discs epoxied together for good measure. The secondary has about a kilometer of 30-gauge magnet wire while the primary holds just ten turns of 8-gauge wire covered with silicone high-voltage insulation.

To decrease the likelihood of arcing, the transformer was placed in a plastic container filled with enough mineral oil liquid dielectric to cover the secondary. After degassing in a vacuum chamber for a day, [SciTubeHD] hooked the primary to a couple of different but equally formidable-looking full-bridge inverters for testing. The coil was capable of some pretty spicy arcs — [SciTubeHD] measured 20 amps draw at 35 volts AC input, so this thing isn’t to be trifled with. STL files for the core parts are coming up soon; we trust schematics for the power supply will be available, too.

Would-be spooks and spies, take note: this one-transistor FM transmitter is a circuit you might want to keep in mind for your bugging needs. True, field agents aren’t likely to need to build their own equipment, but how cool a spy would you be if you could?

Luckily, you won’t need too many parts to recreate [Ciprian (YO6DXE)]’s project, most of which could be found in a decently stocked junk bin, or even harvested from e-waste. On the downside, the circuit is pretty fussy, with even minor component value changes causing a major change in center frequency. [Ciprian] had to do a lot of fiddling to get the frequency in the FM band, particularly with the inductor in the LC tank circuit. Even dropping battery voltage shifted the frequency significantly, which required a zener diode to address.

[Ciprian] ran a few tests and managed to get solid copy out to 80 meters range, which is pretty impressive for such a limited circuit. The harmonics, which extend up into the ham bands and possibly beyond, are a bit of a problem; while those could be addressed with a low-pass filter, in practical terms, the power of this little fellow is probably low enough to keep you from getting into serious trouble. Still, it’s best not to push your luck.

While you’re trying your hand at one-transistor circuits, you might want to try [Ciprian]’s one-transistor CW transceiver next.

Normally, videos over at The Signal Path channel on YouTube have a certain vibe, namely teardowns and deep dives into high-end test equipment for the microwave realm. And while we always love to see that kind of content, this hop into the world of cryogenics and liquid oxygen production shows that [Shahriar] has other interests, too.

Of course, to make liquid oxygen, one must first have oxygen. While it would be easy enough to get a tank of the stuff from a gas supplier, where’s the fun in that? So [Shahriar] started his quest with a cheap-ish off-the-shelf oxygen concentrator, one that uses the pressure-swing adsorption cycle we saw used to great effect with DIY O₂ concentrators in the early days of the pandemic. Although analysis of the machine’s output revealed it wasn’t quite as capable as advertised, it still put out enough reasonably pure oxygen for the job at hand.

The next step in making liquid oxygen is cooling it, and for that job [Shahriar] turned to the cryocooler from a superconducting RF filter, a toy we’re keen to see more about in the future. For now, he was able to harvest the Stirling-cycle cryocooler and rig it up in a test stand with ample forced-air cooling for the heat rejection end and a manifold to supply a constant flow of oxygen from the concentrator. Strategically placed diodes were used to monitor the temperature at the cold end, a technique we can’t recall seeing before. Once powered up, the cryocooler got down to the 77 Kelvin range quite quickly, and within an hour, [Shahriar] had at least a hundred milliliters of lovely pale blue fluid that passed all the usual tests.

While we’ve seen a few attempts to make liquid nitrogen before, this might be the first time we’ve seen anyone make liquid oxygen. Hats off to [Shahriar] for the effort.

Sitting in front of a computer all day isn’t exactly what the firmware between our ears was tuned to do. We’re supposed to be hunting and gathering, not hunting and pecking. So anything that makes the computing experience a little more pleasurable is probably worth the effort, and this premium wireless scroll wheel certainly seems to fit that bill.

If this input device seems familiar, that’s because we featured [Engineer Bo]’s first take on this back at the end of 2024. That version took a lot of work to get right, and while it delivered high-resolution scrolling with a premium look and feel, [Bo] just wasn’t quite satisfied with the results. There were also a few minor quibbles, such as making the power switch a little more user-friendly and optimizing battery life, but the main problem was the one that we admit would have driven us crazy, too: the wobbling scroll wheel.

[Bo]’s first approach to the wobble problem was to fit a larger diameter bearing under the scroll wheel. That worked, but at the expense of eliminating the satisfying fidget-spinner action of the original — not acceptable. Different bearings yielded the same result until [Bo] hit on the perfect solution: a large-diameter ceramic bearing that eliminated the wobble while delivering the tactile flywheel experience.

The larger bearing left more room inside for the redesigned PCB and a lower-profile, machined aluminum wheel. [Bo] also had a polycarbonate wheel made, which looks great as is but would really be cool with internal LEDs — at the cost of battery life, of course. He’s also got plans for a wheel machined from wood, which we’ll eagerly await.

An electric typewriter is a rare and wonderful thrift store find, and even better if it still works. Unfortunately, there’s not as much use for these electromechanical beauties, so if you find one, why not follow [Konstantin Schauwecker]’s lead and turn it into a printer?

The portable typewriter [Konstantin] found, a Silver Reed 2200 CR, looks like a model from the early 1980s, just before PCs and word processing software would sound the death knell for typewriters. This machine has short-throw mechanical keys, meaning that a physical press of each key would be needed rather than electrically shorting contacts. Cue the order for 50 low-voltage solenoids, which are arranged in rows using 3D printed holders and aluminum brackets, which serve as heat sinks to keep the coils cool. The solenoids are organized into a matrix with MOSFET drivers for the rows and columns, with snubber diodes to prevent voltage spikes across the coils, of course. A Raspberry Pi takes care of translating an input PDF file into text and sending the right combination of GPIO signals to press each key.

The action of the space bar is a little unreliable, so page formatting can be a bit off, but other than that, the results are pretty good. [Konstantin] even managed to hook the printer up to his typewriter keyboard, which is pretty cool, too.

We’ve seen tons of projects lately using the ESP32-C3, and for good reason. The microcontroller has a lot to offer, and the current crop of tiny dev boards sporting it make adding a lot of compute power to even the smallest projects dead easy. Not so nice, though, is the poor WiFi performance of some of these boards, which [Peter Neufeld] addresses with this quick and easy antenna.

There are currently a lot of variations of the ESP32-C3 out there, sometimes available for a buck a piece from the usual suspects. Designs vary, but a lot of them seem to sport a CA-C03 ceramic chip antenna at one end of the board to save space. Unfortunately, the lack of free space around the antenna makes for poor RF performance. [Peter]’s solution is a simple antenna made from a 31-mm length of silver wire. One end of the wire is formed into a loop by wrapping it around a 5-mm drill bit and bending it perpendicular to the remaining tail. The loop is then opened up a bit so it can bridge the length of the ceramic chip antenna and then soldered across it. That’s all it takes to vastly improve performance as measured by [Peter]’s custom RSSI logger — anywhere from 6 to 10 dBm better. You don’t even need to remove the OEM antenna.

The video below, by [Circuit Helper], picks up on [Peter]’s work and puts several antenna variants to further testing. He gets similarly dramatic results, with 20 dBm improvement in some cases. He does note that the size of the antenna can be a detriment to a project that needs a really compact MCU and tries coiling up the antenna, with limited success. He also did a little testing to come up with an optimal length of 34 mm for the main element of the antenna.

There seems to be a lot of room for experimentation here. We wonder how mounting the antenna with the loop perpendicular to the board and the main element sticking out lengthwise would work. We’d love to hear about your experiments, so make sure to ping us with your findings.

We’ve got a love-hate relationship with discount tool outlet Harbor Freight: we hate that we love it so much. Apparently, [James Clough] is of much the same opinion, at least now that he’s looked into the quality of their outlet strips and found it somewhat wanting.

The outlet strips in question are Harbor Freight’s four-foot-long, twelve-outlet strips, three of which are visible from where this is being written. [James] has a bunch of them too, but when he noticed an intermittent ground connection while using an outlet tester, he channeled his inner [Big Clive] and tore one of the $20 strips to bits. The problem appears to be poor quality of the contacts within each outlet, which don’t have enough spring pre-load to maintain connection with the ground pin on the plug when it’s wiggled around. Actually, the contacts for the hot and neutral don’t look all that trustworthy either, and the wiring between the outlets is pretty sketchy too. The video below shows the horrors within.

What’s to be done about this state of affairs? That’s up to you, of course. We performed the same test on all our outlets and the ground connections all seemed solid. So maybe [James] just got a bad batch, but he’s still in the market for better-quality strips. That’s going to cost him, though, since similar strips with better outlets are about four times the price of the Harbor Freight units. We did find a similar strip at Home Depot for about twice the price of the HF units, but we can’t vouch for the quality. As always, caveat emptor.

Thanks to [cliff claven] for the tip.

The hits just keep coming for the International Space Station (ISS), literally in the case of a resupply mission scheduled for June that is now scrubbed thanks to a heavy equipment incident that damaged the cargo spacecraft. The shipping container for the Cygnus automated cargo ship NG-22 apparently picked up some damage in transit from Northrop Grumman’s Redondo Beach plant in Los Angeles to Florida. Engineers inspected the Cygnus and found that whatever had damaged the container had also damaged the spacecraft, leading to the June mission’s scrub.

Mission controllers are hopeful that NG-22 can be patched up enough for a future resupply mission, but that doesn’t help the ISS right now, which is said to be running low on consumables. To fix that, the next scheduled resupply mission, a SpaceX Cargo Dragon slated for an April launch, will be modified to include more food and consumables for the ISS crew. That’s great, but it might raise another problem: garbage. Unlike the reusable Cargo Dragons, the Cygnus cargo modules are expendable, which makes them a great way to dispose of the trash produced by the ISS crew since everything just burns up on reentry. The earliest a Cygnus is scheduled to dock at the ISS again is sometime in this autumn, meaning it might be a long, stinky summer for the crew.

By now you’ve probably heard the news that genetic testing company 23andMe has filed for bankruptcy. The company spent years hawking their spit-in-a-tube testing kits, which after DNA sequence analysis returned a report revealing all your genetic secrets. This led to a lot of DNA surprises, like finding a whole mess of half-siblings, learning that your kid isn’t really related to you, and even catching an alleged murderer. But now that a bankruptcy judge has given permission for the company to sell that treasure trove of genetic data to the highest bidder, there’s a mad rush of 23andMe customers to delete their data. It’s supposed to be as easy as signing into your account and clicking a few buttons to delete your data permanently, with the option to have any preserved samples destroyed as well. Color us skeptical, though, that the company would willingly allow its single most valuable asset to be drained. Indeed, there were reports of the 23andMe website crashing on Monday, probably simply because of the rush of deletion requests, but then again, maybe not.

It may not have been 121 gigawatts-worth, but the tiny sample of plutonium that a hapless Sydney “science nerd” procured may be enough to earn him some jail time. Emmanuel Lidden, 24, pleaded guilty to violations of Australia’s nuclear proliferation laws after ordering a small sample of the metal from a US supplier, as part of his laudable bid to collect a sample of every element in the periodic table. Shipping plutonium to Australia is apparently a big no-no, but not so much that the border force officials who initially seized the shipment didn’t return some of the material to Lidden. Someone must have realized they made a mistake, judging by the outsized response to re-seize the material, which included shutting down the street where his parents live and a lot of people milling about in hazmat suits. We Googled around very briefly for plutonium samples for sale, which is just another in a long list of searches since joining Hackaday that no doubt lands us on a list, and found this small chunk of trinitite encased in an acrylic cube for $100. We really hope this isn’t what the Australian authorities got so exercised about that Lidden now faces ten years in prison. That would be really embarrassing.

And finally, we couldn’t begin to tote up the many happy hours of our youth spent building plastic models. New model day was always the best day, and although it’s been a while since we’ve indulged, we’d really get a kick out of building models of some of the cars we had an emotional connection to, like the 1972 Volkswagen Beetle that took us on many high school adventures, or our beloved 1986 Toyota 4×4 pickup with the amazing 22R engine. Sadly, those always seemed to be vehicles that wouldn’t appeal to a broad enough market to make it worth a model company’s while to mass-produce. But if you’re lucky, the car of your dreams might just be available as a download thanks to the work of Andrey Bezrodny, who has created quite a collection of 3D models of off-beat and quirky vehicles. Most of the files are pretty reasonably priced considering the work that obviously went into them, and all you have to do is download the files and print them up. It’s not quite the same experience as taking the shrink-wrap off a Revell or Monogram box and freeing the plastic parts from they’re trees to glue them together, but it still looks like a lot of fun.

Ever want to get into reverse engineering but don’t know where to start? You’re in luck — [Hash] just dropped a case study in chip glitching that should get you off on the right foot.

The object of this reverse engineering effort in the video below is a Microchip SAM4C32C, removed from one of the many smart electrical meters [Hash] loves to tear into. This microcontroller was supposed to be locked to prevent anyone from sniffing around in the code, but after soldering the chip to a target board and plugging it into a Chip Whisperer, [Hash] was able to find some odd-looking traces on the oscilloscope. Of particular interest was an unusual pattern on the scope while resetting the chip, which led him to an AI-assisted search for potential vulnerabilities. This allowed him to narrow down the target time for a power glitch, and in only a few seconds, the chip was forced to bypass its security bit and drop into its boot loader. With the keys to the kingdom, [Hash] was able to read the firmware and find all sorts of interesting tidbits.

Obviously, chip glitching isn’t always as easy as this, and even when a manufacturer leaves a vector like this in the chip, exploiting it does take some experience and finesse. But, if you’re going to get started glitching, it makes sense to start with the low-hanging fruit, and having [Hash] along for the ride doesn’t hurt either.

Tektronix must have been quite a place to work back in the 1980s. The company offered a bewildering selection of test equipment, and while the digital age was creeping in, much of their gear was still firmly rooted in the analog world. And some of the engineering tricks the Tek wizards pulled off are still the stuff of legend.

One such gem of analog design was the SG505, an ultra-low-distortion oscillator module that [Paul] is trying to replicate with modern parts. That’s a tall order since not only did the original specs on this oscillator call for less than 0.0008% total harmonic distortion over a frequency range of 20 Hz to 20 kHz, but a lot of the components it used are no longer manufactured. Tek also tended to use a lot of custom parts, especially mechanical ones like the barrel switch used to select attenuation levels in the SG505, leaving [Paul] no choice but to engineer his way around them.

So far, [Paul] has managed to track down most of the critical components or source suitable substitutes. One major win was locating the original J-FET Tek used in the oscillator’s AGC circuit. One part that’s proven more elusive is the potentiometer that Tek used to adjust the frequency; who knew that finding a dual-gang precision wirewound 10k single-turn pot with no physical stop would be such a chore?

[Paul] still seems to be very much in the planning stages of this project yet, and that’s probably for the best since projects such as these live and die on proper planning. We’re keen to see how this develops, and we’re very much looking forward to seeing the FFT results. We also imagine he’ll be busting out his custom curve tracer at some point in the build, too.

Around these parts, projects needlessly using a microcontroller where a simpler design would do are often derided with the catch-all “Should have used a 555,” even if the venerable timer chip wouldn’t have been the ideal solution. But the sentiment stands that a solution more complicated than it needs to be is probably one that needs rethinking, as this completely mechanical chaser light badge Simple Add-On (SAO) aptly demonstrates.

Rather than choosing any number of circuits to turn a strip of discrete lights on and off, [Johannes] took inspiration for his chaser lights from factory automation mechanisms that move parts between levels on steps that move out of phase with each other, similar to the marble-raising mechanism used in [Wintergatan]’s Marble Machine X.

Two thin plates with notches around the edge are sandwiched together inside the 3D printed case of the SAO, between the face and the light source. A small motor and a series of gears rotate the two masks 180° out of phase with each other, which creates the illusion that the light is moving.

It’s pretty convincing; when we first saw the video below, we were sure it was a row of tiny LEDs around the edge of the badge.

Hats off to [Johannes] for coming up with such a clever mechanism and getting it working just in time for Hackaday Europe. If you need to catch up on the talks, we’ve got a playlist ready for you.

Those who indulge in trading card games know that building the best deck is the key to victory. What exactly that entails is a mystery to us muggles, but keeping track of your cards is a vital part of the process, one that this DIY card scanner (original German; English translation) seeks to automate.

At its heart, [Fraens]’ card scanner is all about paper handling, which is always an engineering task fraught with peril. Cards like those for Magic: The Gathering and other TCGs are meant to be handled by human hands, and automating the task of flipping through them presents some challenges. [Fraens] uses a pair of motorized 3D-printed rollers with O-rings to form a conveyor belt that can pull one card at a time off the bottom of a deck. An adjustable retaining roller made from the most adorable linear bearing we’ve ever seen ensures that only one card at a time is pulled from the hopper onto an imaging platen. An adjustable mount holds a smartphone to take a picture of the card, which is fed into an app that extracts all the details and categorizes the cards in the deck.

Aside from the card handling mechanism, there are some pretty slick details to this build. The first is that [Fraens] noticed that the glossy finish on some cards interfered with scanning, leading him to add a diffused LED ringlight to the rig. If an image isn’t scannable, the light goes through a process of dimming and switching colors until a good scan is achieved. Also, to avoid the need to modify the existing TCG deck management app, [Fraens] added a microphone to the control side of the scanner that listens for the sounds the app makes when it scans cards. And if Magic isn’t your thing, the basic mechanism could easily be modified to scan everything from business cards to old family photos.

A moment’s inattention is all it takes to gather the information needed to make a physical copy of a key. It’s not necessarily an easy process, though, so if pen testing is your game, something like this Flipper Zero key copying toolchain can make the process quicker and easier when the opportunity presents itself.

Of course, we’re not advocating for any illegal here; this is just another tool for your lock-sports bag of tricks. And yes, there are plenty of other ways to accomplish this, but using a Flipper Zero to attack a strictly mechanical lock is kind of neat. The toolchain posted by [No-Lock216] starts with an app called KeyCopier, which draws a virtual key blank on the Flipper Zero screen. The app allows you to move the baseline for each pin to the proper depth, quickly recording the bitting for the key. Later, the bitting can be entered into an online app called keygen which, along with information on the brand of lock and its warding, can produce an STL file suitable for downloading and printing.

Again, there are a ton of ways to make a copy of a key if you have physical access to it, and the comments of the original Reddit post were filled with suggestions amusingly missing the entire point of this. Yes, you can get a key cut at any hardware store for a buck or two that will obviously last a lot longer than a 3D-printed copy. But if you only have a few seconds to gather the data from the key, an app like KeyCopier could be really convenient. Personally, we’d find a smartphone app handier, but if you’ve got a Flipper, why not leverage it?

Thanks to [JohnU] for the tip.

What a long, strange trip it’s been for NASA astronauts Suni Williams and Bruce Wilmore, who finally completed their eight-day jaunt to space after 289 days. The duo returned to Earth from the ISS on Tuesday along with two other returning astronauts in a picture-perfect splashdown, complete with a dolphin-welcoming committee. For the benefit of those living under rocks these past nine months, Williams and Wilmore slipped the surly bonds way back in June on the first crewed test flight of the Boeing Starliner, bound for a short stay on the ISS before a planned return in the same spacecraft. Alas, all did not go to plan as their ride developed some mechanical difficulties on the way upstairs, and so rather than risk their lives on a return in a questionable capsule, NASA had them cool their heels for a couple of months while Starliner headed home without them.

There’s been a lot of talk about how Butch and Suni were “stranded,” but that doesn’t seem fair to us. Sure, their stay on the ISS was unplanned, or at least it wasn’t Plan A; we’re sure this is always a contingency NASA allows for when planning missions. Also unfortunate is the fact that they didn’t get paid overtime for the stay, not that you’d expect they would. But on the other hand, if you’re going to get stuck on a work trip, it might as well be at the world’s most exclusive and expensive resort.

Speaking of space, while it’s statistically unlikely that anyone reading this will ever get there, you can still get a little taste of what space travel is like if you’re willing to give up ten days of your life to lie in a waterbed. What’s more, the European Space Agency will pay you 5,000 euros to do it. The experiment is part of the ESA’s Vivaldi III campaign, an exploration of the effects of extended spaceflight on the human body. The “waterbed” thing is a little misleading, though; since the setup is designed to simulate the posture the body takes in microgravity, they use a tank of water (heated, we hope) with a waterproof cover to submerge volunteers up to their torso. This neutral body posture looks pretty comfortable if you’re sleeping in space, but we tend to think it’d get annoying pretty quickly down here. Especially for potty breaks, which aren’t done astronaut-style but rather by being transferred to a trolley which lets you do your business without breaking from the neutral posture. Still, 5,000 euros is 5,000 euros.

Bad news for the meme-making community, as it appears AI might be coming for you, too. A recent study found that LLMs like ChatGPT can meme better than humans, at least under certain conditions. To come to that conclusion, researchers used some pretty dank meme templates and pitted humans against ChatGPT-4o to come up with meme-worthy captions. They also had a different group of humans collaborate with the LLM to come up with meme captions, which for practical purposes probably means the humans let the chatbot do the heavy lifting and just filtered out the real stinkers. When they showed the memes to crowdsourced participants to rate them on humor, creativity, and shareability, they found that the LLM consistently produced memes that scored higher across all three categories. This makes sense when you think about it; the whole job of an LLM is to look at a bunch of words and come up with a consensus on what the next word should be. Happily, the funniest memes were written by humans, and the human-LLM collaborations were judged more creative and shareable. So we’ve got that going for us, which is good.

We noted the passing of quite a few surplus electronics shops in this space before, and the closing of each of them, understandable as they may, marks the end of an era. But we recently learned about one surplus outfit that’s still going strong. Best Electronics, which specializes in Atari retrocomputing, has been going strong for over 40 years, a neat trick when Atari itself went bankrupt over 30 years ago. While they appear to have a lot of new old stock bits and bobs — they’re said to have acquired “thousands and thousands” of pallets of Atari goods from their Sunnyvale warehouse when the company folded — they also claim to spend a lot of money on engineering development. Their online presence is delightfully Web 1.0, making it pretty hard to sort through, but we think that development is mainly upgraded PCBs for things like joysticks and keyboards. Whatever they’re doing, they should just keep on doing it.

And finally, have you ever seen a knitted breadboard? Now you have, and while it’s of no practical value, we still love it. Alanna Okun made it for the ITP Stupid Hackathon at NYU back in February. There aren’t any instructions or build docs, so it’s not clear how it works, but from the photos we’d guess there’s either conductive yarn or solid copper wire knitted into the pattern to serve as bus bars.

The difference between 3D printing and good 3D printing comes down to attention to detail. There are so many settings and so many variables, each of which seems to impact the other to a degree that can make setting things up a maddening process. That makes anything that simplifies the process, such as this computer vision pressure advance attachment, a welcome addition to the printing toolchain.

If you haven’t run into the term “pressure advance” for FDM printing before, fear not; it’s pretty intuitive. It’s just a way to compensate for the elasticity of the molten plastic column in the extruder, which can cause variations in the amount of material deposited when the print head acceleration changes, such as at corners or when starting a new layer.

To automate his pressure advance calibration process, [Marius Wachtler] attached one of those dirt-cheap endoscope cameras to the print head of his modified Ender 3, pointing straight down and square with the bed. A test grid is printed in a corner of the bed, with each arm printed using a slightly different pressure advance setting. The camera takes a photo of the pattern, which is processed by computer vision to remove the background and measure the thickness of each line. The line with the least variation wins, and the pressure advance setting used to print that line is used for the rest of the print — no blubs, no blebs.

We’ve seen other pressure-advanced calibrators before, but we like this one because it seems so cheap and easy to put together. True, it does mean sending images off to the cloud for analysis, but that seems a small price to pay for the convenience. And [Marius] is hopeful that he’ll be able to run the model locally at some point; we’re looking forward to that.

There’s a classic grade school science experiment that involves extracting juice from red cabbage leaves and using it as a pH indicator. It relies on anthocyanins, pigmented compounds that give the cabbage its vibrant color but can change depending on the acidity of the environment they’re in, from pink in acidic conditions to green at higher pH. And anthocyanins are exactly what power this unusual kinetic art piece.

Even before it goes into action, [Nathalie Gebert]’s Anthofluid is pretty cool to look at. The “canvas” of the piece is a thin chamber formed by plexiglass sheets, one of which is perforated by an array of electrodes. A quartet of peristaltic pumps fills the chamber with a solution of red cabbage juice from a large reservoir, itself a mesmerizing process as the purple fluid meanders between the walls of the chamber and snakes around and between the electrodes. Once the chamber is full, an X-Y gantry behind the rear wall moves to a random set of electrodes, deploying a pair of conductors to complete the circuit. When a current is applied, tendrils of green and red appear, not by a pH change but rather by the oxidation and reduction reactions occurring at the positive and negative electrodes. The colors gently waft up through the pale purple solution before fading away into nothingness. Check out the video below for the very cool results.

We find Anthofluid terribly creative, especially in the use of such an unusual medium as red cabbage juice. We also appreciate the collision of chemistry, electricity, and mechatronics to make a piece of art that’s so kinetic but also so relaxing at the same time. It’s the same feeling that [Nathalie]’s previous art piece gave us as it created images on screens of moving thread.

Here at Hackaday, it’s a pretty safe bet that putting “World’s smallest” in the title of an article will instantly attract comments claiming that someone else built a far smaller version of the same thing. But that’s OK, because if there’s something smaller than this nearly microscopic LED blinky build, we definitely want to know about it.

The reason behind [Mike Roller]’s build is simple: he wanted to build something smaller than the previous smallest blinky. The 3.2-mm x 2.5-mm footprint of that effort is a tough act to follow, but technology has advanced somewhat in the last seven years, and [Mike] took advantage of that by basing his design on an ATtiny20 microcontroller in a WLCSP package and an 0201 LED, along with a current-limiting resistor and a decoupling capacitor. Powering the project is a 220-μF tantalum capacitor, which at a relatively whopping 3.2 mm x 1.6 mm determines the size of the PCB, which [Mike] insisted on using.

Assembling the project was challenging, to say the least. [Mike] originally tried a laboratory hot plate to reflow the board, but when the magnetic stirrer played havoc with the parts, he switched to a hot-air rework station with a very low airflow. Programming the microcontroller almost seemed like it was more of a challenge; when the pogo pins he was planning to use proved too large for the job he tacked leads made from 38-gauge magnet wire to the board with the aid of a micro hot air tool.

After building version one, [Mike] realized that even smaller components were available, so there’s now a 2.4 mm x 1.5 mm version using an 01005 LED. We suspect there’ll be a version 3.0 soon, though — he mentions that the new TI ultra-small microcontrollers weren’t available yet when he pulled this off, and no doubt he’ll want to take a stab at this again.

“The brickings will continue until the printer sales improve!” This whole printer-bricking thing seems to be getting out of hand with the news this week that a firmware update caused certain HP printers to go into permanent paper-saver mode. The update was sent to LaserJet MFP M232-M237 models (opens printer menu; checks print queue name; “Phew!) on March 4, and was listed as covering a few “general improvements and bug fixes,” none of which seem very critical. Still, some users reported not being able to print at all after the update, with an error message suggesting printing was being blocked thanks to non-OEM toner. This sounds somewhat similar to the bricked Brother printers we reported on last week (third paragraph).

The trouble is, some users are reporting the problem even if they had genuine HP toner installed. Disturbingly, HP support seems to be fine with this, saying that older HP toner “may no longer be recognized due to new security measures.” Well, there’s your problem, lady! The fix, of course, is to buy yet more genuine HP toner, even if your current cartridge still has plenty of life left in it. That’s a pretty deplorable attitude on HP’s part, and more than enough reason to disable automatic firmware updates, or better yet, just disconnect your printer from the Internet altogether.

Here’s a pro-tip for all you frustrated coders out there: no matter how hard the job gets, planting a logic bomb in your code is probably not the right way to go. That’s the lesson that one Davis Lu learned after being convicted of “causing intentional damage to protected computers” thanks to malicious code he planted in his employer’s system. Apparently not optimistic about his future prospects with Eaton Corp. back in 2018, Lu started adding code designed to run a series of infinite loops to delete user profiles. He also went for the nuclear option, adding code to shut the whole system down should it fail to find an Active Directory entry for him. That code was apparently triggered on the day he was fired in 2019, causing global problems for his former employer. Look, we’ve all been there; coding is often lonely work, and it’s easy to fantasize about coding up something like this and watching them squirm once they fire you. But if it gets that bad, you should probably put that effort into finding a new gig.

Then again, maybe the reason you’re dissatisfied with your coding job is that you know some smart-ass LLM is out there waiting to tell you that you don’t know how to code. That’s what happened to one newbie Cursor user who tried to get help writing some video game code from the AI code editor. The LLM spat back about 750 lines of code but refused to reveal the rest, and when he asked to explain why, it suggested that he should develop the logic himself so that he’d be able to understand and maintain the code, and that “Generating code for others can lead to dependency and reduced learning opportunities.” True enough, but do we really need our AI tools to cop an attitude?

And finally, if you’re anything like us, you’re really going to love this walking tour of a container ship’s mechanical spaces. The ship isn’t named, but a little sleuthing suggests it’s one of the Gülsün-class ships built for MSC in 2019, possibly the MSC Mina, but that’s just a guess. This 400-meter monster can carry 23,656 twenty-foot equivalent units, and everything about it is big. Mercifully, the tour isn’t narrated, not that it would have been possible, thanks to the screaming equipment in the engine room. There are captions, though, so you’ll at least have some idea of what you’re looking at in the immaculately clean and cavernously huge spaces. Seriously, the main engine room has to have at least a dozen floors; being on the engineering crew must mean getting your steps in every day. The most striking thing about the tour was that not a single other human being was visible during the entire hour. We suppose that’s just a testament to how automated modern vessels have become, but it still had a wonderfully creepy liminal feeling to it. Enjoy!

From the styling of this article’s title, some might assume that the Hackaday editors are asleep at the switch this fine day. While that might be true — it’s not our turn to watch them — others will recognize this tortured phrasing as one way to use the 1,000 most commonly used words in the English language to describe a difficult technical project, such as [Attoparsec]’s enormous and enormously impractical ten-hundred word keyboard.

While the scale of this build is overwhelming enough, the fact that each key delivers a full word rather than a single character kind of throws the whole keyboard concept out the window. The 60×17 matrix supports the 1,000 most common English words along with 20 modifier keys, which allow a little bit of cheating on the 1-kiloword dictionary by letting you pluralize a word or turn it into an adjective or adverb. Added complexity comes from the practical limits of PCB fabrication, which forces the use of smaller (but still quite large) PCBs that are connected together. Luckily, [Attoparsec] was able to fit the whole thing on five identical PCBs, which were linked together with card-edge connectors.

The list of pain points on this six-month project is long, and the video below covers them all in detail. What really stood out to us, though, was the effort [Attoparsec] put into the keycaps. Rather than 3D printing his own, he used dye sublimation to label blank keycaps with the 1,000 words. That might sound simple, but he had to go through a lot of trial and error before getting a process that worked, and the results are quite nice. Another problem was keeping the key switches aligned while soldering, which was solved with a 3D printed jig. We also appreciate the custom case to keep this keyboard intact while traveling; we’re going to keep that build-your-own road case service in mind for future projects.

This mega-keyboard is a significant escalation from [Attoparsec]’s previous large keyboard project. The results are pretty ridiculous and impractical, but that’s just making us love it more. The abundance of tips and tricks for managing a physically expansive project are just icing on the cake.

Have you seen Severance? Chances are good that you have; the TV series has become wildly popular in its second season, to the point where the fandom’s dedication is difficult to distinguish from the in-universe cult of [Kier]. Part of the show’s appeal comes from its overall aesthetic, which is captured in this description of the building of one of the show’s props.

A detailed recap of the show is impossible, but for the uninitiated, a mega-corporation called Lumon has developed a chip that certain workers have implanted in their brains to sever their personalities and memories into work and non-work halves. The working “Innies” have no memory of what their “Outies” do when they aren’t at work, which sounds a lot better than it actually ends up being. It’s as weird as it sounds, and then some.

The prop featured here is the “WoeMeter” from episode seven of season two, used to quantify the amount of woe in a severed worker — told you it was weird. The prop was built by design house [make3] on a short timeline and after seeing only some sketches and rough renders from the production designers, and had to echo the not-quite-midcentury modern look of the whole series. The builders took inspiration from, among other things, a classic Nagra tape recorder, going so far as to harvest its knobs and switches to use in the build. The controls are all functional and laid out in a sensible way, allowing the actors to use the device in a convincing way. For visual feedback, the prop has two servo-operated meters and a string of seven-segment LED displays, all controlled by an ESP-32 mounted to a custom PCB. Adding the Lumon logo to the silkscreen was a nice touch.

The prop maker’s art is fascinating, and the ability to let your imagination run wild while making something that looks good and works for the production has got to be a blast. [make3] really nailed it with this one.

Thanks to [Aaron’s Outie] for the tip.

If you were one of the earliest of early adopters in the home computing revolution, you might have had to settle for paper tape mass storage. It was slow, it was bulky, but it was what you had, and that gave it a certain charm that’s hard to resist. And that charm is what [Joshua Coleman] captures with this DIY paper tape reader build.

If the overall style of this project looks familiar, it’s because it was meant to echo the design themes from [Joshua]’s Coleman Z-80 modular computer. The electronics of the reader are based on [David Hansel]’s take on a paper tape reader, which in turn was meant to complement his Altair 8080 simulator — it’s retrocomputers all the way down! [Joshua]’s build has a few bells and whistles to set it apart, though, including an adjustable read head, parametric 3D-printed reels, and a panel mounted ammeter, just because. He also set it up to be a sort of keyboard wedge thanks to an internal relay that bypasses the reader unless it’s actually playing back a tape. Playback speed is pretty fast; see the video below for details.

So far, writing the tapes is an offline process. [Joshua] uses a Python program to convert ASCII to an SVG file and uses a laser cutter to burn holes in lengths of paper, which are then connected together to form a longer tape. A logical next step might be to build a feeder that moves a paper tape across the bed of the laser cutter in sync with the conversion program, to create continuous paper tapes. Or, there’s always the old-school route of solenoid-powered punch and die. We’d be thrilled with either.

It’s been a busy week in space news, and very little of it was good. We’ll start with the one winner of the week, Firefly’s Blue Ghost Mission 1, which landed successfully on the Moon’s surface on March 2. The lander is part of NASA’s Commercial Lunar Payload Services program and carries ten scientific payloads, including a GPS/GNSS receiver that successfully tracked signals from Earth-orbiting satellites. All of the scientific payloads have completed their missions, which is good because the lander isn’t designed to withstand the long, cold lunar night only a few days away. The landing makes Firefly the first commercial outfit to successfully soft-land something on the Moon, and being the first at anything is always a big deal.

Slightly less impressive was Intuitive Machines’ attempt at a landing a day later. Their NOVA-C robotic lander Athena managed a somewhat controlled landing, but the spacecraft is lying on its side rather than upright, a surprisingly common failure mode for recent lunar landings. Also in the failure category is the loss of the world’s first private asteroid mining mission, as well as SpaceX Starship test flight 8, which ended in spectacular fashion this week as Starship exploded soon after booster separation. As usual, Scott Manley has the best analysis of the incident, which seemed to involve a fire in the engine bay that led to a rapid loss of thrust from four of its six engines, and sent the spacecraft tumbling before tearing itself apart. The only good news from the flight was the third successful catch of the returning booster by the chopsticks, which just never gets old.

What does get old is stories about printer manufacturers and their anti-consumer hijinks, especially when it involves one of the only manufacturers who wasn’t playing the “buy our consumables or we brick it” game. In addition to just about every other printer maker, Brother now stands accused of sending firmware up to printers that turns off functionality if non-OEM cartridges are used. The accusations come from Louis Rossman, well-known for his right-to-repair advocacy and, ironically, long-time proponent of Brother printers as least likely to be bricked. His accusation that “Brother is now among the rest of them” is based on a pretty small sample of affected users, and a self-selected one at that, so take that with the requisite amount of salt. For their part, Brother denies the claim, stating simply that “Brother firmware updates do not block the use of third-party ink in our machines.” They don’t go much beyond that by way of an explanation of what’s happening to the users reporting problems other than to say that the users may be confused by the fact that “we like to troubleshoot with Brother Genuine supplies.” What the real story is is anyone’s guess at this point, and the best advice we can offer is either to avoid printers altogether, or just buy the cheapest one you can get and harvest it for parts once the starter cartridges are empty.

If like us you’ve accumulated a large collection of physical media films and TV shows to while away the long dark days of a post-apocalyptic nightmare where Netflix and Hulu are but a distant memory, you might want to rethink your strategy. Some DVD aficionados have found a troubling trend with “DVD rot,” especially with discs manufactured by Warner Brothers Discovery between 2006 and 2008. It’s not clear what’s going on, but it looks like the polycarbonate cover is delaminating from the inner Mylar layer, resulting in cloudy areas that obscure the data. Warner is aware of the problem and will replace defective discs with the same title if possible, or exchange it for a title of like value if the original is no longer available. We’re dismayed that this defect probably includes our beloved Looney Tunes collection, but on the upside, now we have an excuse to sit through forty straight hours of cartoons.

And finally, if you were a NASA rocket engineer in the 1960s, skipping leg day wasn’t an option. That’s because the Saturn V full-stack shake test on the Apollo program was a very hands-on feet-on process. The shake test was performed to make sure nothing was loose on the stack, and that it would be able to withstand not only the shaking induced by those five massive F-1 engines, but also the occasional hurricane that Florida is famous for. To get the rocket shaking, engineers sat on the deck of the gantry with their legs bridging the gap and their feet up against the side of the service module and gave it all they had. Other engineers literally backed them up, to provide something to push against, while another team on the uppermost platform used a rope to play tug-of-war with the command module. They were able to get the stack moving pretty good, with a meter or so of deflection at the escape tower. It does raise the question, though: what would they have done if the test failed?

The late 1950s were such an optimistic time in America. World War II had been over for less than a decade, the economy boomed thanks to pent-up demand after years of privation, and everyone was having babies — so many babies. The sky was the limit, especially with new technologies that promised a future filled with miracles, including abundant nuclear power that would be “too cheap to meter.”

It didn’t quite turn out that way, of course, but the whole “Atoms for Peace” thing did provide the foundation for a lot of innovations that we still benefit from to this day. This 1958 film on “The Armour Research Reactor” details the construction and operation of the world’s first privately owned research reactor. Built at the Illinois Institute of Technology by Atomics International, the reactor was a 50,000-watt aqueous-homogenous design using a solution of uranyl sulfate in distilled water as its fuel. The core is tiny, about a foot in diameter, and assembled by hand right in front of the camera. The stainless steel sphere is filled with 90 feet (27 meters) of stainless tubing to circulate cooling water through the core. Machined graphite reflector blocks surrounded the core and its fuel overflow tank (!) before the reactor was installed in “biological shielding” made from super-dense iron ore concrete with walls 5 feet (1.5 m) thick — just a few of the many advanced safety precautions taken “to ensure completely safe operation in densely populated areas.”

While the reactor design is interesting enough, the control panels and instrumentation are what really caught our eye. The Fallout vibe is strong, including the fact that the controls are all right in the room with the reactor. This allows technicians equipped with their Cutie Pie meters to insert samples into irradiation tubes, some of which penetrate directly into the heart of the core, where neutron flux is highest. Experiments included the creation of radioactive organic compounds for polymer research, radiation hardening of those new-fangled transistors, and manufacturing radionuclides for the diagnosis and treatment of diseases.

This mid-century technological gem might look a little sketchy to modern eyes, but the Armour Research Reactor had a long career. It was in operation until 1967 and decommissioned in 1972, and similar reactors were installed in universities and private facilities all over the world. Most of them are gone now, though, with only five aqueous-homogenous reactors left operating today.

There’s been a lot of buzz about Meshtastic lately, and with good reason. The low-power LoRa-based network has a ton of interesting use cases, and as with any mesh network, the more nodes there are, the better it works for everyone. That’s why we’re excited by this super-affordable Meshtastic kit that lets you get a node on the air for about ten bucks.

The diminutive kit, which consists of a microcontroller and a LoRa module, has actually been available from the usual outlets for a while. But [concretedog] has been deep in the Meshtastic weeds lately, and decided to review its pros and cons. Setup starts with flashing Meshtastic to the XIAO ESP32-S3 microcontroller and connecting the included BLE antenna. After that, the Wio-SX1262 LoRa module is snapped to the microcontroller board via surface-mount connectors, and a separate LoRa antenna is connected. Flash the firmware (this combo is supported by the official web flasher), and you’re good to go.

What do you do with your new node? That’s largely up to you, of course. Most Meshtastic users seem content to send encrypted text messages back and forth, but as our own [Jonathan Bennett] notes, a Meshtastic network could be extremely useful for emergency preparedness. Build a few of these nodes, slap them in a 3D printed box, distribute them to willing neighbors, and suddenly you’ve got a way to keep connected in an emergency, no license required.

Just about any 3D printer can be satisfying to watch as it works, but delta-style printers are especially hypnotic. There’s just something about the way that three linear motions add up to all kinds of complex shapes; it’s mesmerizing. Deltas aren’t without their problems, though, which led [Bruno Schwander] to undertake a trio of interesting mods on his Anycubic Kossel.

First up was an effort to reduce the mass of the business end of the printer, which can help positional accuracy and repeatability. This started with replacing the stock hot-end with a smaller, lighter MQ Mozzie, but that led to cooling problems that [Bruno] addressed with a ridiculously overpowered brushless hairdryer fan. The fan expects a 0 to 5-VDC signal for the BLDC controller, which meant he had to build an adapter to allow Marlin’s 12-volt PWM signal to control the fan.

Once the beast of a fan was tamed, [Bruno] came up with a clever remote mount for it. A 3D-printed shroud allowed him to mount the fan and adapter to the frame of the printer, with a flexible duct connecting it to the hot-end. The duct is made from lightweight nylon fabric with elastic material sewn into it to keep it from taut as the printhead moves around, looking a bit like an elephant’s trunk.

Finally, to solve his pet peeve of setting up and using the stock Z-probe, [Bruno] turned the entire print bed into a strain-gauge sensor. This took some doing, which the blog post details nicely, but it required building a composite spacer ring for the glass print bed to mount twelve strain gauges that are read by the venerable HX711 amplifier and an Arduino, which sends a signal to Marlin when the head touches the bed. The video below shows it and the remote fan in action.

The current generation of USB-powered soldering irons have a lot going for them, chief among them being portability and automatic start and stop. But an iron that turns off in the middle of soldering a joint is a problem, one that this capacitive-touch replacement control module aims to fix.

The iron in question is an SJ1 from Awgem, which [DoganM95] picked up on Ali Express. It seems well-built, with a sturdy aluminum handle, a nice OLED display, and fast heat-up and cool-down. The problem is that the iron is triggered by motion, so if you leave it still for more than a second or two, such as when you’re soldering a big joint, it turns itself off. To fix that,[DoganM95] designed a piggyback board for the OEM controller with a TTP223 capacitive touch sensor. The board is carefully shaped to allow clearance for the existing PCB components and the heater cartridge terminals, and has castellated connections so it can connect to pads on the main board. You have to remove one MOSFET from the main board, but that’s about it for modifications. A nickel strip makes contact with the inside of the iron’s shell, turning it into the sensor plate for the TTP223.

[DoganM95] says that the BA6 variant of the chip is the one you want, as others have a 10-second timeout, which would defeat the purpose of the mod. It’s a very nice bit of design work, and we especially like how the mod board nests so nicely onto the OEM controller. It reminds us a little of those Quansheng handy-talkie all-band mods.

Jack of all trades, master of none, as the saying goes, and that’s especially true for PCB prototyping tools. Sure, it’s possible to use a CNC router to mill out a PCB, and ditto for a fiber laser. But neither tool is perfect; the router creates a lot of dust and the fiberglass eats a lot of tools, while a laser is great for burning away copper but takes a long time to burn through all the substrate. So, why not put both tools to work?

Of course, this assumes you’re lucky enough to have both tools available, as [Mikey Sklar] does. He doesn’t call out which specific CNC router he has, but any desktop machine should probably do since all it’s doing is drilling any needed through-holes and hogging out the outline of the board, leaving bridges to keep the blanks connected, of course.

Once the milling operations are done, [Mikey] switches to his xTool F1 20W fiber laser. The blanks are placed on the laser’s bed, the CNC-drilled through holes are used as fiducials to align everything, and the laser gets busy. For the smallish boards [Mikey] used to demonstrate his method, it only took 90 seconds to cut the traces. He also used the laser to cut a solder paste stencil from thin brass shim stock in only a few minutes. The brief video below shows the whole process and the excellent results.

In a world where professionally made PCBs are just a few mouse clicks (and a week’s shipping) away, rolling your own boards seems to make little sense. But for the truly impatient, adding the machines to quickly and easily make your own PCBs just might be worth the cost. One thing’s for sure, though — the more we see what the current generation of desktop fiber lasers can accomplish, the more we feel like skipping a couple of mortgage payments to afford one.