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AT&T’s Unix PC — We Hardly Knew You

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Before Linux, there was Unix. It was great, but it was and has been plagued by problems with licensing and proprietary competition. [Vintage Appartus] recalls, for example, the AT&T Unix PC from the 1980s. It was awesome, but you’ve probably never heard of it. For 1985, it was a nice setup. You got a 10 MHz Motorola 68010, 512K of RAM (but upgradable to 4M), a floppy, a modem, a 720×384 monochrome screen, and a 10 or 20 MB hard drive. You can check out the video explaining the machine and its problems below. Physically, the computer looked like a high-end Apple ][ with a removable keyboard and a built-in monitor. Expansion was via three slots. Cold start took about three minutes, and then you have a fairly normal Unix setup for the period. The sample machine uses a disk emulator, so the video shows the computer running much faster than it would with a real period hard drive. The card also has an 8086 expansion board that can boot MSDOS, an important feature in 1985. ...

Electronics Near Zero

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Normally, when you design an electronic gadget, you worry about how hot it will get. Automotive-grade components, for example, often have higher allowable temperatures than commercial parts. However, extremely cold environments, such as deep space or the interiors of quantum computers, are also challenging. Researchers at King Abdullah University of Science and Technology believe gallium oxide may be key to operating near absolute zero. According to [Vishal Khandelwal], one of the researchers, most conventional electronics fail below -173C or 100K. Quantum computers routinely operate at 4K. However, β-Ga 2 O 3 is a wide-bandgap semiconductor that has low current leakage and works at high temperatures up to 500C. However, it also avoids the freeze-out effect that traps electrons in other semiconductor materials. The team built two devices from the material seeded with a silicon dopant. The first was a FET with a fin-shaped geometry. The second was an inverter. Both operated reliabl...

USB-C Charger Juices Up 100 Devices At Once

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Back when phones used to ship with chargers in the box, you’d get a plugpack that could charge one device. Aftermarket manufacturers eventually started making chargers with four or five ports which were great for travelling. But what if you wanted to charge even more devices? You might build something like this rig from [DENKI OTAKU]. The goal was to build a charger that could handle 100 devices at once. The charger is designed to charge devices at up to 1.5 amps. That’s no mean feat, as the device would have to be able to deliver 150 amps total when fully loaded. As for the actual design, though, it’s relatively simple. [DENKI OTAKU] simply built a simple USB-C charger PCB based around an off-the-shelf chip which has ten individual chargers on it, and stacked it up ten of those in a housing made out of aluminium extrusion. To deliver the current to run all these chargers, the rig got two massive switching power supplies to feed the charger array a massive amount of c...

Five Different Styles of Cardboard Hinges

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Simple paper hinge. (Credit: Itoshige Studio, YouTube) One doesn’t generally associate cardboard with structural components like hinges, but [Itoshige Studio] assures us that you can absolutely create hinges out of this ubiquitous material . In total the video covers five different designs, ranging from the simple and straightforward to an interlocking tab design that approximates a typical steel hinge with paper rod to keep both sides of the hinge together. The most simple hinge is unsurprisingly just a strip of craft paper, which is also demonstrated as the hinge for a wooden box in lieu of the typical metal hinge. This same principle is then demonstrated for a fancy cardboard box. From here the hinge designs increasingly get more involved, with first a seamless hinge variation, and then a kamichoban hinge design that’s inspired by traditional Japanese room dividers and furniture, using panels that are interconnected with overlapping sections to create a fascinatingly f...

Making the Osmo Pocket 4 a More Serious Camera

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The Osmo Pocket 4 is a handheld gimballed camera that’s perfect for shooting running content on the go. However, it’s got a weird sort of form factor and is limited when it comes to things like fitting filters or recording quality sound. To that end, [Byron Seven] whipped up an upgrade kit that turns the Pocket 4 into more of a “real” camera. The idea is simple enough—the Osmo Pocket 4 is packaged in a 3D printed shell that expands its capabilities. It’s tucked into the structure with a USB power bank that greatly increases how long you can shoot before the batteries run out. In front of the gimbal head, there’s a fitting that allows attaching standard camera filters for visual effect. Topside there’s a handle for better physical control of the camera, along with a rail mount for a DJI wireless mic and a phone to act as a monitor. Down below, there’s a quick-connect fitting so the camera can be slammed on and off a tripod with ease. What’s great is that you can slot a Pocket 4 into t...

Why Model Collapse in LLMs is Inevitable With Self-Learning

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There is a persistent belief in the ‘AI’ community that large language models (LLMs) have the ability to learn and self-improve by tweaking the weights in their vector space. Although there’s scant evidence that tweaking a probability vector space is anything like the learning process in biological brains, we nevertheless get sold the idea that artificial general intelligence (AGI) is just around the corner if we do just enough tweaking. Instead of emerging super intelligence, the most likely outcome is what is called model collapse, with a recent paper by [Hector Zenil] going over the details on why self-training/learning in LLMs and similar systems is a fool’s errand. For those who just want the brief summary with all the memes, [Metin] wrote a blog post covering the basics . In the end an LLM as well as a diffusion model (DM) is a statistical model of input data using which a statistically likely output can be generated (inferred) based on an input query. It follows intuitively ...

How to Kill Humidity Sensors With Humidity

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An often overlooked section in the datasheets for popular humidity sensors like the BME280 and DHT22 is the ‘non-condensing humidity’ bit, which puts an important constraint on which environments you can use this sensor in. This was the painful lesson that [Mellow Labs] recently had to learn when multiple of such sensors had kicked the bucket after being used in a nicely steamed-up bathroom. Fortunately, it introduced him to sensors that are rated for use in condensing humidity environments, such as the SHT40 that’s demonstrated in the video. This particular sensor is made by Sensirion, and as we can see in the datasheet it features a built-in heater that allows it to keep working even in a condensing environment. This heater has three heating levels which are controlled via the I2C interface, though duration is limited to one second in order to prevent overheating the sensor. Of note is that you cannot take measurements while the heater is operating, and its use obviously increa...