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Showing posts from October, 2025

The Great ADS1115 Pricing and Sourcing Mystery

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The AdaFruit ADS1115 board hooked up for testing. (Credit: James Bowman) Following up on the recent test of a set of purported ADS1115 ADCs sourced from Amazon [James Bowman] didn’t just test a genuine Ti part , but also dug into some of the questions that came up after the first article . As expected, the AdaFruit board featuring a presumed genuine Ti ADS1115 part performed very well, even performing significantly better on the tested parameters than the datasheet guarantees. Thus we can confirm that when you get the genuine Ti part, you can expect very good and reliable performance for your ADC purposes. Which leaves the unaddressed questions about what these cheapo Amazon-sourced ADS1115 ICs are, and how it can be that LCSC has what should be the same parts for so much cheaper than US distributors? As far as LCSC pricing is concerned, these are likely to be genuine parts, but also the subject of what is known as price discrimination . This involves pricing the same product dif...

Making a Cardboard Airplane Wing

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Ideally, an aircraft would be made of something reasonably strong, light, and weather resistant. Cardboard, is none of those things. But that did not stop [PeterSripol] from building an ultralight wing out of cardboard. Firstly, he wanted to figure out the strongest orientation of the cardboard flutes for the wing spars. He decided on a mix of horizontal and vertical flutes for the wing spar, with the horizontal flutes resisting vertical deformations and the vertical flutes resisting chord wise deformations. The main spar is made up of two long strips of these cardboard pieces, glued together with a single sheet of cardboard on the top and bottom to create a structural beam. Unfortunately, the glue had not fully dried on one of the sheets before making the spar resulting in the final spar warping. Fortunately, the first wing was always intended to be tested to destruction. The wing’s ribs are made of laser cut cardboard, with doublers on the inside providing greater surface area fo...

Tiny UPS Keeps WiFi Online

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For any mission-critical computer system, it’s a good idea to think about how the system will handle power outages. At the very least it’s a good idea to give the computer enough time to gracefully shut down if the power outage will last for an indefinite time. But for extremely critical infrastructure, like our home Wi-Fi, we might consider a more long-term battery backup that can let us get through the longest of power outages . Part of why this project from [ ] works so well is that most off-the-shelf routers don’t actually use that much energy. Keeping that and a modem online when the power is out only requires a few lithium batteries. To that end, three lithium ion cells are arranged in series to provide the router with between 9 and 12 volts, complete with a battery management system (BMS) to ensure they aren’t over- or under-charged and that they are balanced. The router plugs directly into a barrel jack, eliminating any switching losses from having to use an inverter during b...

The Isetta TTL Computer Makes Some Noise

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Our Hackaday colleague [Bil Herd] is known for being the mind behind the Commodore 128, a machine which famously had both a 6502 and a Z80 processor on board. The idea of a machine which could do the job of both those processors in hardware while containing neither would have blown the mind of any 1980s computer enthusiast, yet that’s exactly what [Roelh]’s Isetta TTL computer does. It’s an extremely clever design whose targeted microcode allows the processor-swap trick, and since he’s brought it from prototype to production and has it running SymbOS since we last saw it, it’s time we gave it another look. All the functions on what is a surprisingly compact board. The video below the break shows the machine in action, with the Windows 95-like SymbOS GUI running a series of sound tests in the emulated AY-3-8910 sound generator, as well as a  Lemmings -like game. It also runs Sinclair ZX Spectrum software, giving it access to a huge library. We were lucky enough to see some of...

Making the Smallest and Dumbest LLM with Extreme Quantization

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Turns out that training on Twitch quotes doesn’t make an LLM a math genius. (Credit: Codeically, YouTube) The reason why large language models are called ‘large’ is not because of how smart they are, but as a factor of their sheer size in bytes. At billions of parameters at four bytes each, they pose a serious challenge when it comes to not just their size on disk, but also in RAM, specifically the RAM of your videocard (VRAM). Reducing this immense size, as is done routinely for the smaller pretrained models which one can download for local use, involves quantization. This process is explained and demonstrated by [Codeically], who takes it to its logical extreme: reducing what could be a GB-sized model down to a mere 63 MB by reducing the bits per parameter. While you can offload a model, i.e. keep only part of it in VRAM and the rest in system RAM, this massively impacts performance. An alternative is to use fewer bits per weight in the model, called ‘compression’, which typica...

Keep An Eye On Your Air-Cooled Engine

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There was a time, long ago, when passenger vehicles used to be much simpler than they are today. There were many downsides of this era, safety chief among them, but there were some perks as well. They were in general cheaper to own and maintain, and plenty could be worked on with simple tools. There’s perhaps no easier car to work on than an air-cooled Volkswagen, either, but for all its simplicity there are a number of modern features owners add to help them with these antiques. [Pegor] has created his own custom engine head temperature monitor for these vehicles . As one could imagine with an air-cooled engine, keeping an eye on the engine temperature is critical to ensuring their longevity but the original designs omitted this feature. There are some off-the-shelf aftermarket solutions but this custom version has a few extra features that others don’t. It’s based on a ATMega32u4 microcontroller and will work with any K-type thermocouple, and thanks to its open nature can use a wid...

A Logical Clock That Pretends To Be Analog

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[kcraske] had a simple plan for their clock build. They wanted a digital clock that was inspired by the appearance of an analog one, and they only wanted to use basic logic, with no microprocessors involved. Ultimately, they achieved just that. Where today you might build a clock based around a microcontroller and a real-time clock module, or by querying a network time server, [kcraske] is doing all the timekeeping in simpler hardware. The clock is based around a bunch of 74-series logic chips, a CD4060 binary counter IC, and a 32.768 KHz crystal, which is easy to divide down to that critical 1 Hz. Time is displayed on the rings of LEDs around the perimeter of the clock—12 LEDs for hours, and 60 each for minutes and seconds. Inside the rings, the ICs that make up the clock are arranged in a pleasant radial configuration. It’s a nice old-school build that reminds us not everything needs to run at 200 MHz or hook up to the internet to be worthwhile. We’ve featured some other fun old-s...

2025 Component Abuse Challenge: Nail Your Next Decal

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One of the hardest parts of a project — assuming it makes it that far — is finishing it up in an aesthetically pleasing manner. As they say, the devil is in the details, wearing Prada. Apparently the devil also has an excellent manicure, because [Tamas Feher] has come up with a way to introduce incredibly detailed decals (down to 0.1 mm) in cheap, repeatable fashion, using a technique borrowed from the local nail salon.  The end result can look quite a bit better than the test piece above. For those who aren’t in to nail art (which, statistically speaking, is likely to be most of you) there is a common “stamping” technique for putting details onto human fingernails. Nail polish is first applied to voids on a stencil-like plate, then picked up by a smooth silicone stamper, which is then pressed against the nail, reproducing the image that was on the stencil. If that’s clear as mud, there’s a quick demo video embedded bellow. There’s a common industrial technique that works the ...

UK’s MAST Upgrade Tokamak Stabilizes Plasma with Edge Magnetic Fields

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Although nuclear fusion is exceedingly easy to achieve, as evidenced by desktop fusors, the real challenges begin to pop up whenever you try to sustain a plasma for extended periods of time, never mind trying to generate net energy output. Plasma instability was the reason why 1950s UK saw its nuclear fusion hopes dashed when Z-pinch fusion reactors failed to create a stable plasma, but now it seems that another UK fusion reactor is one step closer to addressing plasma instability, with the MAST Upgrade tokamak demonstrating the suppressing of ELMs. ELMs, or edge localized modes, are instabilities that occur at the edge of the plasma. A type of magnetohydrodynamic instability , ELMs were first encountered after the switch to high-confinement mode (H-mode) to address instability issues encountered in the L-mode operating regime of previous tokamaks. These ELMs cause damage on the inside of the reactor vessel with these disturbances ablating the plasma-facing material. One of the sol...

Tinkercad in Color

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Tinkercad is famous for having lots of colors in the interface. But once you export an STL, that file is notoriously monochrome. If you are printing with a single color printer, no problems. But if you have a color printer, what do you do? [CHEP] shows some options , including a relatively new one, in the video below. The simple way is to “paint” the STL inside your slicer. But as [CHEP] shows, that is a pain and also has some undesirable side effects. A better approach is to export each part (or, at least, each part of the same color) into separate STL files, which you can then import together in the slicer. You still have to paint, but you don’t have to select different faces, and the resulting coloring is more what you’d expect. However, we also learn about a new Tinkercad feature: bundle groups. This is like the traditional “union group,” except it preserves the part structure in the export file. Now you can import a single file, split it into parts, and get a similar result to...

Handheld PC Build Is Pleasantly Chunky

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The cool thing about building your own computer is that you don’t have to adhere to industry norms of form and function. You can build whatever chunky, awesome thing your heart desires, and that’s precisely what [Rahmanshaber] did with the MutantC cyberdeck. The build is based around a Raspberry Pi Compute Module 4. If you’re unfamiliar with the Compute Module, it’s basically a Raspberry Pi that has been designed specifically for easy integration into a larger carrier PCB. In this case, the carrier PCB interfaces all the other necessary gear to make this a fully functional computer. The PCB is installed inside a vaguely-rectangular 3D-printed enclosure, with a 5-inch TFT LCD on a sliding mount. Push the screen up, and it reveals a small-format keyboard for text entry. There’s also a hall-effect joystick and a couple of buttons for mouse control to boot. [Rahmanshaber] has designed the computer to run off a couple of different battery packs—you can use a pair of 18650 cells if you lik...

FLOSS Weekly Episode 852: Sir, This is a Wendy’s

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This week Jonathan talks to Robert Wolff about DevEco ! How did this developer group come to be, and what is its purpose? What are the lessons learned about building communities and working with others? Watch to find out! https://linktr.ee/deveco https://linktr.ee/robertwolff https://linktr.ee/thedeveco https://thedeveco.com/ https://discord.gg/deveco 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/P08crTF

Tinkercad Continues to Grow Up

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It is easy to write off Tinkercad as a kid’s toy. It is easy enough for kids to learn and it uses bright colors looking more like a video game than a CAD tool. We use a variety of CAD tools, but for something quick, sometimes Tinkercad is just the ticket. Earlier this year, Tinkercad got a sketch feature, something many other CAD programs have and, now, you can even revolve the sketch to form complex objects. Tinkercad guru [HL ModTech] shows you how in the video below. It wasn’t long ago that we needed to cut an irregular shape out of an STL and we found the sketch feature whic was perfect for that purpose. If you’ve used other CAD tools, you’ll know that sketches are typically 2D shapes that get changed into a 3D shape. The traditional thing is to simply extrude it, so if you draw a circle in 2D, you get a cylinder. However, you can also revolve a profile around a center point. In that case, a circle would give you a torus or, you know, a doughnut-shape. In Tinkercad these are t...

Batteries Not Included: Meet the Swiss Réglette!

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Over on YouTube, [The Modern Rogue] created an interesting video showing a slide-rule-like encryption device called the Réglette . This was a hardware implementation of a Vigenère-like Cipher, technically referred to as a manual polyalphabetic substitution cipher . The device requires no batteries, is fully waterproof, daylight readable and easy to pack, making it really useful if you find yourself in a muddy trench in the middle of winter during a world war. Obviously, because it’s a slide rule. Anyway, so how does this cipher work? Well, the ‘polyalphabetic’ bit infers the need for a key phrase, which is indeed the first thing all parties need to agree upon. Secondly, a number is required as a reference point. As you can see from the video, the sliding part of the device has letters of the alphabet, as well as numbers and a special symbol. The body has two series of numbers, with the same spacing as the central, sliding part. A second copy of the sliding part is also needed to slid...

Open Source Hack Lets The Razer Nari Headset Work With Linux

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The Razer Nari is a decent wireless headset, but it’s a little oddball—because it uses a bespoke USB dongle for pairing. This is all well and good if you’re using a supported configuration; plug it into a Windows PC, run the utility, and you’re good to go. If you’re a Linux user, though, you were out of luck— but [JJ] has just solved that problem. The tool was created by reverse engineering the pairing protocol used by Razer’s own proprietary software. [JJ] figured out the necessary pairing command, and how to send it to both the dongle and the headset. The headset itself must be connected by a USB cable when initiating the pairing process. [JJ] believes the tool should work with any Razer Nari and dongle variant. However, the Nari Ultimate and Nari Essential models are yet to be tested, with verification still required. However, the pairing commands were extracted from Razer’s own tool and don’t appear to differ so it should probably work across the board .  Setup is still a li...

Building a Minecraft Lantern for Halloween

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Sometimes it’s fun to bring props from video games into the real world. [Hulk] has done just that with their latest Halloween build— creating a working replica of the lantern from Minecraft . Key to the build is the 3D printed enclosure, which faithfully mimics the look of the in-game item. By virtue of Minecraft’s simplistic visual style, it’s a relatively straightforward print, without a lot of quirky geometry or difficult overhangs that might otherwise trip up your printer. It’s printed in six parts and assembled with acrylic lenses which act to diffuse the light coming from inside. Electronically, an Arduino Nano runs the show. It’s hooked up to a pair of NeoPixel addressable LED rings, which provide rich RGB colors on demand. Rotary pots are installed on the enclosure to enable the color to be tuned to the user’s desire. Power is courtesy of an 18650 lithium-ion cell and a TP4056 module ensures the battery is kept happy when charging. It’s a fun prop build, and one that would...

The Lambda Papers: When LISP Got Turned Into a Microprocessor

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The physical layout of the SCHEME-78 LISP-based microprocessor by Steele and Sussman. (Source: ACM, Vol 23, Issue 11, 1980) During the AI research boom of the 1970s, the LISP language – from LISt Processor – saw a major surge in use and development, including many dialects being developed. One of these dialects was Scheme, developed by [Guy L. Steele] and [Gerald Jay Sussman], who wrote a number of articles that were published by the Massachusetts Institute of Technology (MIT) AI Lab as part of the AI Memos. This subset, called the Lambda Papers , cover the ideas from both men about lambda calculus, its application with LISP and ultimately the 1980 paper on the design of a LISP-based microprocessor . Scheme is notable here because it influenced the development of what would be standardized in 1994 as Common Lisp, which is what can be called ‘modern Lisp’. The idea of creating dedicated LISP machines was not a new one, driven by the processing requirements of AI systems. The mism...

High Performance Motor Control With FOC From the Ground Up

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Testing the FOC-based motor controller. (Credit: Excessive Overkill, YouTube) Vector Control, also known as Field Oriented Control or FOC is an AC motor control scheme that enables fine-grained control over a connected motor, through the precise control of its phases. In a recent video [Excessive Overkill] goes through the basics and then the finer details of how FOC works, as well as how to implement it. These controllers generally uses a proportional integral (PI) loop, capable of measuring and integrating the position of the connected motor, thus allowing for precise adjustments of the applied vector. If this controller looks familiar, it is because we featured it previously in the context of reviving old industrial robotic arms. Whether you are driving the big motors on an industrial robot, or a much smaller permanent magnet AC (PMAC) motor, FOV is very likely the control mechanism that you want to use for the best results. Of note is that most BLDC motors are actually also ...

Blinking An LED With a Single Transistor

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Let’s say you want to blink an LED. You might grab an Arduino and run the Blink sketch, or you might lace up a few components to a 555. But you needn’t go so fancy! [The Design Graveyard] explains how this same effect can be achieved with a single transistor. The circuit in question is rather odd at first blush. The BC547 NPN transistor is hooked up between an LED and a resistor leading to a 12V DC line, with a capacitor across the emitter and collector. Meanwhile, the base is connected to… nothing! It’s just free-floating in the universe of its own accord. You might expect this circuit to do nothing at all, but if you power it up, the LED will actually start to flash. The mechanism at play is relatively simple. The capacitor charges to 12 volts via the resistor. At this point, the transistor, which is effectively just acting as a poor diode in this case, undergoes avalanche breakdown at about 8.5 to 9 volts, and starts conducting. This causes the capacitor to discharge via the LED,...

Fail of the Week: Beaker to Benchy More Bothersome than Believed

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Making nylon plastic from raw chemicals used to be a very common demo; depending where and when you grew up, you may well have done it in high school or even earlier. What’s not common is taking that nylon and doing something with it, like, say extruding it into filament to make a benchy. [Startup Chuck] shows us there might be a reason for that . (Video, embedded below.) It starts out well enough: sebacoyl chloride and hexamethaline diamine mix up and do their polymerizing tango to make some nylon, just like we remember. (Some of us also got to play with mercury bare-handed; safety standards have changed and you’ll want to be very careful if you try this reaction at home). The string of nylon [Chuck] pulls from the beaker even looks a little bit like filament for a second, at least until it breaks and gets tossed into a blobby mess. We wonder if it would be possible to pull nylon directly into 1.75 mm filament with the proper technique, but quality control would be a big issue. Even...