Kritik sah

For over a decade, most passports have contained an NFC chip that holds a set of electronically readable data about the document and its holder. This has resulted in a much quicker passage through some borders as automatic barriers can replace human officials, but at the same time, it adds an opaque layer to the process. Just what data is on your passport, and can you read it for yourself? [Terence Eden] wanted to find out . The write-up explains what’s on the passport and how to access it. Surprisingly, it’s a straightforward process, unlike, for example, the NFC on a bank card. Security against drive-by scanning is provided by the key being printed on the passport, requiring the passport to be physically opened. He notes that it’s not impossible to brute force this key, though doing so reveals little that’s not printed on the document. The write-up reveals a piece of general-purpose technical knowledge we should all know. However, there’s a question we’re left with that it doesn’...

Old hardware tends to get less support as the years go by, from both manufacturers and the open-source community alike. And yet, every now and then, we hear about fresh attention for an ancient device. Consider the ancient SoundBlaster sound card that first hit the market 31 years ago. [Mark] noticed that a recent update squashed a new bug on an old piece of gear. Jump over to the Linux kernel archive, and you’ll find a pull request for v6.16-rc3 from [Takashi Iwai]. The update featured fixes for a number of sound devices, but one stands out amongst the rest. It’s the SoundBlaster AWE32 ISA sound card, with [Iwai] noting “we still got a bug report after 25 years.” The bug in question appears to have been reported in 2023  by a user running Fedora 39 on a 120 MHz Pentium-based machine. The fixes themselves are not  particularly interesting. They merely concern minutiae about the DMA modes used with the old hardware. The new updates ensure that DMA modes cannot be changed w...

The Ceran discs, freshly cut from the old stovetop and awaiting polishing. (Credit: Huygens Optics) Ceran is a name brand for a type of glass ceramic that has a very low coefficient of thermal expansion (CTE). This is useful for stovetops, but it is also a highly desirable property for optical glass. The natural question: Can an old ceramic stovetop be upcycled into something visually striking? This is the topic of the most recent video in [Huygens Optics]’s series on glass ceramics. Interestingly, by baking sections of the Ceran glass ceramic for 10 minutes at 961 °C, the CTE can be lowered by another five times, from 0.5 ppm / °C to a mere 0.1 ppm / °C. Following baking, you need a lot of grinding and polishing to remove any warping, existing textures, and printing. After polishing with 220 grit by hand for a few minutes, most of these issues were fixed, but for subsequent polishing, you want to use a machine to get the required nanometer-level precision, as well as to survive ...

Some of the largest objects in the night sky to view through a telescope are galaxies and supernova remnants, often many times larger in size than the moon but generally much less bright. Even so, they take up a mere fraction of the night sky, with even the largest planets in our solar system only taking up a few arcseconds and stars appearing as point sources. There are more things to look at in the sky than there are telescopes, regardless of size, so it might almost seem like an impossible task to see everything. Yet that’s what this new telescope in Chile aims to do . The Vera C. Rubin Observatory plans to image the entire sky every few nights over a period lasting for ten years. This will allow astronomers to see the many ways the cosmos change with more data than has ever been available to them. The field of view of the telescope is about 3.5 degrees in diameter, so it needs to move often and quickly in order to take these images. At first glance the telescope looks like an...

You know what the worst thing about the Steam Deck is? Being able to play your games on the go. Wouldn’t it be better if it was a screenless brick that lived under your TV? Well, maybe not, but at least one person thought so, because [Interfacing Linux] has created the GeekDeck, a Steam OS console of sorts in this video embedded below. The hack is as simple as can be: he took a GEEKOM A5, a minicomputer with very similar specs to the Steam Deck, and managed to load SteamOS onto it. We were expecting that to be a trial that took most of the video’s runtime, but no! Everything just… sorta worked. It booted to a live environment and installed like any other Linux. Which was unexpected, but Steam has released SteamOS for PC.  In case you weren’t aware, SteamOS is an immutable distribution based on Arch Linux. Arch of course has all the drivers to run on… well, any modern PC, but it’s the immutable part that we were expecting to cause problems. Immutable distributions are locked dow...

Most standing desks on the market use electric motors or hand cranks to raise and lower the deck. However, [Matthias Wandel] found a Kloud standing desk that used an altogether different set up. He set about figuring out how it worked in the old-fashioned way— by pulling it apart. The Kloud desk relies on pneumatics rather than electrical actuators to move up and down. Inside the desk sits a small tank that can be pressurized with a hand-cranked mechanism. A lever can then be used to release pressure from this tank into a pair of pneumatic cylinders that drive the top of the desk upwards. The two cylinders are kept moving in sync by a tensioned metal ribbon that ties the two sides together. The mechanism is not unlike a gas lift chair—holding the lever and pushing down lets the desk move back down. Once he’s explained the basic mechanism, [Matthias] gets into the good stuff—pulling apart the leg actuator mechanism to show us what’s going on inside in greater detail. If you’ve ever t...

These days, so much of what we see online is delivered by social media algorithms. The operations of these algorithms are opaque to us; commentators forever speculate as to whether they just show us what they think we want to see, or whether they try to guide our thinking and habits in a given direction. The Digital Poison device  from [Lucretia], [Auxence] and [Ramon] aims to twist and bend the algorithm to other ends. The concept is simple enough. The device consists of a Raspberry Pi 5 operating on a Wi-Fi network. The Pi is set up with scripts to endlessly play one or more select YouTube videos on a loop. The videos aren’t to be watched by anyone; the device merely streams them to rack up play counts and send data to YouTube’s recommendation algorithm. The idea is that as the device plays certain videos, it will skew what YouTube recommends to users sharing the same WiFi network based on perceived viewer behavior. To achieve subtle influence, the device is built inside an un...

[Ralph] is excited about impedance matching, and why not? It is important to match the source and load impedance to get the most power out of a circuit. He’s got a whole series of videos about it. The latest? Matching using a PI network and the venerable Smith Chart . We like that he makes each video self-contained. It does mean if you watch them all, you get some review, but that’s not a bad thing, really. He also does a great job of outlining simple concepts, such as what a complex conjugate is, that you might have forgotten. Smith charts almost seem magical, but they are really sort of an analog computer. The color of the line and even the direction of an arrow make a difference, and [Ralph] explains it all very simply. The example circuit is simple with a 50 MHz signal and a mismatched source and load. Using the steps and watching the examples will make it straightforward, even if you’ve never used a Smith Chart before. The red lines plot impedance, and the blue lines show co...

[Ruud], the creator of [Capturing Dust], started his latest video with what most of us would consider a solved problem: the dust collection system for his shop already had a three-stage centrifugal dust separator with more than 99.7% efficiency. This wasn’t quite as efficient as it could be, though, so [Ruud]’s latest upgrade shrinks the size of the third stage while increasing efficiency to within a rounding error of 99.9%. The old separation system had two stages to remove large and medium particles, and a third stage to remove fine particles. The last stage was made out of 100 mm acrylic tubing and 3D-printed parts, but [Ruud] planned to try replacing it with two parallel centrifugal separators made out of 70 mm tubing. Before he could do that, however, he redesigned the filter module to make it easier to weigh, allowing him to determine how much sawdust made it through the extractors. He also attached a U-tube manometer (a somewhat confusing name to hear on YouTube) to measure ...

For as versatile and inexpensive as switch-mode power supplies are at all kinds of different tasks, they’re not always the ideal choice for every DC-DC circuit. Although they can do almost any job in this arena, they tend to have high parts counts, higher complexity, and higher cost than some alternatives. [Jasper] set out to test some alternative linear chargers called low dropout regulators (LDOs) for small-scale charging of lithium ion capacitors against those more traditional switch-mode options. The application here is specifically very small solar cells in outdoor applications, which are charging lithium ion capacitors instead of batteries. These capacitors have a number of benefits over batteries including a higher number of discharge-recharge cycles and a greater tolerance of temperature extremes, so they can be better off in outdoor installations like these. [Jasper]’s findings with using these generally hold that it’s a better value to install a slightly larger solar cell ...

In theory, writing a Linux device driver shouldn’t be that hard, but it is harder than it looks. However, using libusb, you can easily deal with USB devices from user space, which, for many purposes, is fine.  [Crescentrose] didn’t know anything about writing user-space USB drivers until they wrote one and documented it for us. Oh, the code is in Rust, for which there aren’t as many examples. The device in question was a USB hub with some extra lights and gadgets. So the real issue, it seems to us, wasn’t the code, but figuring out the protocol and the USB stack. The post covers that, too, explaining configurations, interfaces, and endpoints. There are other ancillary topics, too, like setting up udev. This lets you load things when a USB device (or something else) plugs in. Of course, you came for the main code. The Rust program is fairly straightforward once you have the preliminaries out of the way. The libusb library helps a lot. By the end, the code kicks off some thread...

Procedural generation is a big part of game design these days. Usually you generate your map, and [Fractal Philosophy] has decided to go one step further: using a procedurally-generated world from an older video, he is procedurally generating history by simulating the rise and fall of empires on that map in a video embedded below. Now, lacking a proper theory of Psychohistory, [Fractal Philosophy] has chosen to go with what he admits is the simplest model he could find, one centered on the concept of “solidarity” and based on the work of [Peter Turchin], a Russian-American thinker. “Solidarity” in the population holds the Empire together; external pressures increase it, and internal pressures decrease it. This leads to an obvious cellular automation type system (like Conway’s Game of Life), where cells are evaluated based on their nearest neighbors: the number of nearest neighbors in the empire goes into a function that gives the probability of increasing or decreasing the solidarit...

[Claywoven] mostly prints with ceramics, although he does produce plastic inserts for functional parts in his designs. The ceramic parts have an interesting texture, and he wondered if the same techniques could work with plastics, too. It turns out it can , as you can see in the video below. Ceramic printing, of course, doesn’t get solid right away, so the plastic can actually take more dramatic patterns than the ceramic. The workflow starts with Blender and winds up with a standard printer. The example prints are lamps, although you could probably do a lot with this technique. You can select where the texturing occurs, which is important in this case to allow working threads to avoid having texture. You will need a Blender plugin to get similar results. The target printer was a Bambu, but there’s no reason this wouldn’t work with any FDM printer. We admire this kind of artistic print. We’ve talked before about how you can use any texture to get interesting results . If you need ...

We haven’t seen any projects from serial experimenter [Les Wright] for quite a while, and honestly, we were getting a little worried about that. Turns out we needn’t have fretted, as [Les] was deep into this exploration of the Pockels Effect , with pretty cool results. If you’ll recall, [Les]’s last appearance on these pages concerned the automated creation of huge, perfect crystals of KDP , or potassium dihydrogen phosphate. KDP crystals have many interesting properties, but the focus here is on their ability to modulate light when an electrical charge is applied to the crystal. That’s the Pockels Effect, and while there are commercially available Pockels cells available for use mainly as optical switches, where’s the sport in buying when you can build? As with most of [Les]’s projects, there are hacks galore here, but the hackiest is probably the homemade diamond wire saw. The fragile KDP crystals need to be cut before use, and rather than risk his beauties to a bandsaw or angle g...

This week Jonathan chats with Davide Bettio and Paul Guyot about AtomVM! Why Elixir on embedded? And how!? And what is a full stack Elixir developer, anyways? Watch to find out! https://atomvm.org/ https://github.com/atomvm/AtomVM https://popcorn.swmansion.com/ https://www.kickstarter.com/projects/multiplie/la-machine Did you know you can watch the live recording of the show right on our YouTube Channel ? Have someone you’d like us to interview? Let us know, or contact the guest and have them contact us! Take a look at the schedule here . Direct Download in DRM-free MP3. If you’d rather read along, here’s the transcript for this week’s episode . Places to follow the FLOSS Weekly Podcast: Spotify RSS Theme music: “Newer Wave” Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License from Blog – Hackaday https://ift.tt/sGHtaMO

Spending time as wee hackers perusing the family atlas taught us an appreciation for a good map, and [Billy Roberts], a cartographer at NREL, has served up a doozy with a map of the data center infrastructure in the United States. [via LinkedIn ] Fiber optic lines, electrical transmission capacity, and the data centers themselves are all here. Each data center is a dot with its size indicating how power hungry it is and its approximate location relative to nearby metropolitan areas. Color coding of these dots also helps us understand if the data center is already in operation (yellow), under construction (orange), or proposed (white). Also of interest to renewable energy nerds would be the presence of some high voltage DC transmission lines on the map which may be the future of electrical transmission. As the exact location of fiber optic lines and other data making up the map are either proprietary, sensitive, or both, the map is only available as a static image. If you’re itchin...

Leica’s film cameras were hugely popular in the 20th century, and remain so with collectors to this day. [Michael Suguitan] has previously had great success converting his classic Leica into a digital one, and now he’s taken the project even further. [Michael’s] previous work saw him create a so-called “digital back” for the Leica M2. He fitted the classic camera with a Raspberry Pi Zero and a small imaging sensor to effectively turn it into a digital camera, creating what he called the LeicaMPi. Since then, [Michael] has made a range of upgrades to create what he calls the LeicaM2Pi. The upgrades start with the image sensor. This time around, instead of using a generic Raspberry Pi camera, he’s gone with the fancier ArduCam OwlSight sensor. Boasting a mighty 64 megapixels, it’s still largely compatible with all the same software tools as the first-party cameras, making it both capable and easy to use. With a  crop factor of 3.7x, the camera’s Voigtlander 12mm lens has a much m...

The choice between hardware and software for electronics projects is generally a straighforward one. For simple tasks we might build dedicated hardware circuits out of discrete components for reliability and low cost, but for more complex tasks it could be easier and cheaper to program a general purpose microcontroller than to build the equivalent circuit in hardware. Every now and then we’ll see a project that blurs the lines between these two choices like this Pong game built entirely out of discrete components . The project begins with a somewhat low-quality image of the original Pong circuit found online, which [atkelar] used to model the circuit in KiCad. Because the image wasn’t the highest resolution some guesses needed to be made, but it was enough to eventually produce a PCB and bill of material. From there [atkelar] could start piecing the circuit together, starting with the clock and eventually working through all the other components of the game, troubleshooting as he wen...

If you do anything with electronics or electricity, it is a good bet you have a multimeter. Even the cheapest meter today would have been an incredible piece of lab gear not long ago and, often, meters today are lighter and have more features than the old Radio Shack meters we grew up with. But then there are bench meters. [Learn Electronics Repair] reviews an OWON XDM1241 meter, and you have to wonder if it is better than just a decent handheld device. Check out the video below and see what you think. Some of the advantage of a bench meter is just convenience. They stay in one place and often have a bigger display than a handheld. Of course, these days, the bench meter isn’t much better than a handheld anyway. In fact, one version of this meter even has a battery, if you want to carry it around. Traditionally, bench meters had more digits and counts, although that’s not always true anymore. This meter has 55,000 counts with four and a half digits. It has a large LCD, can connect ...

The Blackberry made phones with real keyboards popular, and smartphones with touch keyboards made that input method the default. However, the old flip phone crowd had just a few telephone keys to work with. If you have a key-limited project, maybe check out the libt9 library from [FoxMoss]. There were two methods for using these limited keyboards, both of which relied on the letters above a phone key’s number. For example, the number 2 should have “ABC” above it, or, sometimes, below it. In one scheme, you’d press the two key multiple times quickly to get the letter you wanted. One press was ‘2’ while two rapid presses made up ‘A.’ If you waited too long, you were entering the next letter (so pressing two, pausing, and pressing it again would give you ’22’ instead of ‘A’). That’s a pain, as you might imagine. The T9 system was a bit better. It “knows” about words. So if you press, for example, ‘843’ it knows you probably meant ‘the,’ a common word. That’s better than ‘884444333’ ...

At one point in time mechanical seven segment displays were ubiquitous, over time many places have replaced them with other types of displays. [Sebastian] has a soft spot for these old mechanically actuated displays and has built an open-source 7-segment display with some very nice features. We’ve seen a good number of DIY 7-segment displays on this site before, the way [Sebastian] went about it resulted in a beautiful well thought out result. The case is 3D printed, and although there are two colors used it doesn’t require a multicolor 3d printer to make your own. The real magic in this build revolves around the custom PCB he designed. Instead of using a separate electromagnets to move each flap, the PCB has coil traces used to toggle the flaps. The smart placement of a few small screws allows the small magnets in each flap to hold the flap in that position even when the coils are off, greatly cutting down the power needed for this display. He also used a modular design where one b...

We’ve all seen the exploded view of complex things, which CAD makes possible, but it’s much harder to levitate parts in their relative positions in the real world. That, however, is exactly what [fellerts] has done with this wristwatch , frozen in time and place. Inspired by another great project explaining the workings of a mechanical watch, [fellerts] set out to turn it into reality. First, he had to pick the right watch movement to suspend. He settled on a movement from the early 1900s—complex enough to impress but not too intricate to be impractical. The initial approach was to cast multiple layers that stacked up. However, after several failed attempts, this was ruled out. He found that fishing line was nearly invisible in the resin. With a bit of heat, he could turn it into the straight, transparent standoffs he needed. Even after figuring out the approach of using fishing line to hold the pieces at the right distance and orientation, there were still four prototypes before m...

Composting doesn’t seem difficult: pile up organic matter, let it rot. In practice, however, it’s a bit more complicated– if you want that sweet, sweet soil amendment in a reasonable amount of time, and to make sure any food-born pathogens and weed seeds don’t come through, you need a “hot” compost pile. How to tell if the pile is hot? Well, you could go out there and stick your arm in like a schmuck, or you could use [Dirk-WIllem van Gulik]’s “ LORAWAN Compostheap solarpowered temperaturesensor ” (sic). The project is exactly what it sounds like, once you add some spaces: a solar-powered temperature sensor that uses LoRaWAN to track temperatures inside (and outside, for comparison) the compost heap year round. Electronically it is pretty simple: a Helltech CubeCell AB01 LoraWAN module is wired up with three DS18B20 temperature sensors, a LiPo battery and a solar panel. (The AB01 has the required circuitry to charge the battery via solar power.) The three temperature sensors are spr...

Learning new instruments is never a simple task on your own; nothing can beat the instant feedback of a teacher. In our new age of AI, why not have an AI companion complain when you’re off note? This is exactly what [Ada López] put together with their AI-Powered Piano Trainer . The basics of the piano rely on rather simple boolean actions, either you press a key or not. Obviously, this sets up the piano for many fun projects, such as creative doorbells or helpful AI models. [Ada López] started their AI model with a custom dataset with images of playing specific notes on the piano. These images then get fed into Roboflow and trained using the YOLOv8 model. Using the piano training has the model run on a laptop and only has a Raspberry Pi for video, and gives instant feedback to the pianist due to the demands of the model. Placing the Pi and an LCD screen for feedback into a simple enclosure allows the easy viewing of how good an AI model thinks you play piano. [Ada López] demos thei...