2026-02-24 03:30:12
You can get an IDE to USB bridge from all the usual sources, but you may find those fail on the older drives in your collection– apparently they require drives using logical block addressing, which did not become standard until the mid-1990s. Some while some older drives got in on the LBA game early, you were more likely to see Cylinder-Head-Sector (CHS) addressing. That’s why [JJ Dasher], a.k.a [redruM0381] created ATABoy, an open-source IDE bridge that can handle the oldest drives that fit on the bus.
The heart of the build is an RP2350, which serves as both IDE and USB host controller. To computer, after a little bit of setup, the drive attached to ATABoy shows up as a regular USB mass storage device. A little bit of setup is to be expected with drives of this vintage, you may remember. Luckily [JJ] included a handy BIOS-themed configuration utility that can be accessed through any serial console. He says you’ll usually be able to get away with “Auto Detect & Set Geometry,” but if you need to plug in the CHS values yourself, well, it’ll feel just like old times. Seeing is believing, so check it out in the demo video embedded below.
Though the custom PCB has a USB-C connector, and the USB-C standard could provide enough power for ye olde spinning rust drives, [JJ] didn’t include any power delivery with ATABoy. If you’re using it with a desktop, you can use the PSU in the box; MOLEX hasn’t changed. If you’re on a laptop, you’ll need another power supply– perhaps this USB-C powered benchtop unit.
If you’re using a Raspberry Pi or similar SBC, go ahead and skip USB entirely–the GIPO can do PATA IDE.
2026-02-24 02:00:27
You wake up in the middle of the night. Is it time to get up? Well, you can look at the nightstand clock. Unless your partner is in the way. Whoops. Even then, without your glasses, the time is just a fuzzball of light. You could ask Alexa, but that’s sure to wake your partner, too. The answer is a projection clock. In its modern form, it shoots a digital time display on a wall or ceiling with digits so large that you don’t need your glasses. If you can see the ceiling, you can tell what time it is.
A modern invention, of course. No, not really. According to [Roger Russel], a UK patent in 1909 used an analog clock face and lightbulbs to project the clock face and hands on the ceiling. Unfortunately, [Roger’s] website is no more, but the Wayback Machine is on the job. You can see a device of the same type at the British Museum.
In 1938, [Leendert Prins] filed for a patent on a similar projection clock. Sometimes known as “ceiling clocks” or “night clocks,” these devices often have a regular clock visible as well as a way to project the time. In the old days, this was often an image of a translucent analog clock lit up by light bulbs. In the modern era, it is almost always either LEDs or an LCD with a halogen backlight. Of course, there are many variations. A clock might use numbers on a rotating drum with a lamp behind it, for example.
It isn’t hard to imagine someone putting a pocket watch in a magic lantern as a prototype. In general, some bright light source has to pass through a condenser lens. The light then travels through the LCD or translucent clock face. Finally, a projector lens expands the image.
We couldn’t find much about the actual history of old projection clocks outside of [Roger’s] defunct website. But if you can project an image and build a clock, all you need is the idea to combine them.
Want to get one and tear it open to see how it works? You don’t have to since [Soudnmisen] and [svetnovinek.cz] already did that for you, as you can see in the videos below.
Of course, what you project doesn’t have to be just the time. We’ve seen clocks that can project the weather, for example. But, usually, all you need in the middle of the night is the time.
Clocks are always a fun project, and a projection clock is certainly in the realm of a homebrew project. You could use a lot of methods to form the clock face, or, like [OSO POLAR MOVIES] did in the video below, just shine a light on your analog clock. Sure, that’s cheating, but it is certainly a hack.
If you prefer, try an LCD. Or a VFD. If you want to go analog and can’t put together a translucent clock face, try making a clock face from a mirror. You can remove the marks and numbers so they don’t reflect, and then use normal clock hands, which will block light just fine. You’ll just have to reverse the clock movement to run backwards, but that’s easy, too.
How about you? What strange method would you use to draw the time on the ceiling? A laser and a galvo come to mind. A tiny CRT? Then again, you could just mount a giant display on your ceiling. That’s how they did it at a Kentucky library. Let us know your plans in the comments, and when you have it done, send us a tip.
2026-02-24 00:30:13
One of the issues with nuclear power plants is that they produce long-lived radioactive waste. Storing spent nuclear fuel is a real problem. However, researchers at the Department of Energy’s Thomas Jefferson National Accelerator Facility have made strides not only to produce more electricity from spent fuel but also to break it down into shorter-lived nuclear waste. [Aman Tripathi] shares the details about NEWTON, a program to fire high-energy protons at a target to produce a flood of neutrons that can interact with nuclear waste. You can read the original press release, too.
Short-lived, of course, is a relative term. Unprocessed spent fuel may be dangerous for about 100,000 years. After the proposed processing, the danger period is down to “only” 300 years. On the plus side, the process generates a lot of heat, which you can convert to electricity in the usual way.
While 300 years is a long time, it isn’t difficult to imagine storing waste for that period of time. So why isn’t this a no-brainer? The process is not efficient. You need cryogenic cooling for superconducting, although there is work to make higher-temperature alternatives.
The other hurdle is power usage. You probably have a microwave oven with a magnetron. The magnetron in this project needs 10 megawatts of power. Researchers hope to process all of the US nuclear waste within the next 30 years.
If you haven’t heard of Jefferson Labs, don’t feel bad. But their YouTube channel is full of fun physics demos that would work well in a science class or with any group of kids. For example, check out “Can it Roll” below.
If you think locking up waste for 100,000 years is easy, keep in mind the oldest Egyptian pyramid is about 5,000 years old. Another alternative is to find a way to use the waste, but that can be challenging as well.
2026-02-23 23:00:26
Automotive airbags are key safety devices that aim to reduce injuries and mortality in the event of motor vehicle accidents. These rapidly-inflating cushions act to soften the blow of an impact, catching occupants of the vehicle and preventing them from hitting hard parts of the vehicle’s interior.
Airbags are rigorously tested to perform as faultlessly as possible under all conditions. However, no system is perfect, and every automotive component has an expected service life. The question is—how old is too old when it comes to airbags? The answer is not exactly straightforward.
Every given component of a car has a lifespan. A set of quality spark plugs might last 100,000 km in service, while an air filter might be rated for a year or two before replacement is due. In some cases, automakers might deem a given component to last the life of the car. A great example is “lifetime” rated transmission fluid, where the automaker doesn’t expect it to ever need to be changed. That’s not because the fluid lasts forever, but because they expect the car to be scrapped before the fluid is no longer serviceable. Oftentimes, automakers have gotten this guess wrong, and owners find themselves struggling to change the fluid on transmissions that were never designed to allow such replacement. Generally, this attitude is because automakers aren’t incentivised to consider how their vehicles run in the years after the factory warranty has run out.
As far as airbags are concerned, they’ve generally been treated as a component that is expected to last the life of the vehicle. If the engine is running and the doors are still on, the airbags should be fine, goes the thinking. Barring exceptional cases like Takata’s deadly malfunctioning airbags, of course. The problem is that what an automaker considers a vehicle’s useful lifetime is often not the same as the owner’s own opinion. A luxury automaker doesn’t think you’ll still be driving today’s newest model in ten year’s time, while a vintage car enthusiast might still be happily driving a 30-year-old car in 2026.
We know, just from observation, that airbags in ten-year-old cars are still perfectly functional in the vast majority of cases. However, we’re now getting to the point where there are cars with airbags that are hitting their 30th and 40th birthdays, and they’re still on the road. Owners of these vehicles are starting to wonder if they can trust the somewhat explosive devices that are, in many cases, aimed directly at the face.
Airbags were first developed in the 1960s, and reached production cars in the mid-1970s. They would grow in prominence in the 1980s, before eventually becoming mandatory in major markets like the US in the mid-1990s. Take any automaker producing a car with airbags in 1985, for example. It probably wasn’t particularly concerned with how that car would perform in 2026. A fair call, perhaps, given the vast majority of vehicles built in that year have since left the roads, but it’s an active concern for those who do own the dwindling members of the class of 1985.
The problem we have in this regard is that, for most vehicles, we just don’t know how the airbags hold up over those sort of timeframes. This sort of testing is a difficult thing to do. There are accelerated aging techniques that can be used to test some types of equipment, but they’re not always applicable and are an estimation at best. If you’re building a car in 1985, you can make some assumptions do some calculations that suggest your airbag will last for a given timespan after manufacture, and that’s about as good as it gets.
We do have some data on hand. It’s limited, but it gives us a guide as to how airbags are performing in the wild. In the mid-1990s, IIHS tested a couple of 1973 Chevrolet Impalas in and found that these ancient, early airbags performed okay in a simple crash test. Technology has only improved since then, so one would assume many of our more modern airbags would perform well over even longer time periods. Meanwhile, queries made to manufacturers by Edmunds indicated that the industry widely believes older airbags to be still functional over extended time periods. Hence the lack of service intervals or mandated regular inspections for these devices.
Notably, Mercedes-Benz is one automaker that spells out airbag lifetimes quite clearly—and not every example from the German automaker gets a “good forever” rating. Speaking to Hagerty, the automaker noted that the company’s earlier airbags in vehicles sold prior to January 1992 are rated for a service life of just 15 years. Those vehicles would have been due for airbag replacements in 2007 at the latest. Replacement dates were listed on stickers placed on the vehicle on these models. However, Mercedes-Benz vehicles produced after this date have airbags with no service life limit, and are “not required to be replaced.” This, of course, does not count the limited number of models built with Takata airbags, which were subject to recall just as were models from many other automakers.
The industry line is that old airbags are fine. We also don’t have a lot of evidence to suggest that airbags in popular 1980s and 1990s models are hurting anyone just yet. For those reasons, if you do have an older car, a wise gambler would probably say you’re better off leaving it alone rather than being all paranoid and ripping the airbag out.
Vague assertions that airbags are mostly okay forever may not assuage your fears when you’re sitting behind the window of your kinda-junky 1999 Honda Prelude on a sunny day in 2041. Sure, the NHTSA isn’t ringing alarm bells about 90s cars maiming people in highway accidents just yet, but who knows what another decade or two will bring. Is there anything more to be done?
Sitting here in 2026, we could try and collect data today on how old airbags are holding up. However, there are some logistical hurdles that would make this relatively difficult. You could purchase a bunch of airbags from scrapped cars that are 30 or 40 years old, test fire them in an instrumented laboratory, and determine if they operated safely. Or you could simply run crash tests with old cars. However, such an effort would be hugely expensive and time-intensive. Beyond the engineering staff required and the cost of purchasing old vehicles, to get useful data, you’d have to test lots of cars. If you test a single 1984 Ford Tempo and find the airbags are bad after 40 years, you don’t really know if it’s one bad example or if the airbags in all the cars are bad. You’d really need to test a bunch of Ford Tempos to get a better idea, perhaps 10 or even 100 cars. Even then, the data would still be very limited in application. You’d have found that Ford Tempo airbags from 1984 were okay, but what about when Ford switched to a new inflator design in 1989? What about the larger Ford models, or any of the thousands of other airbags in other models from other manufacturers? Each design could perform differently over time, based on conditions of manufacture, how well the airbags are sealed, and the type of propellant used.
The issue doesn’t even stop with the airbags themselves. They must be triggered by a dedicated electronic module which detects a vehicle impact and determines when and how to fire the airbags in the vehicle. One thing we do know is that a lot of 40-year-old electronics start to fail when their capacitors leak or dry out, to say nothing of other age-related failure modes due to vibration or heat cycles. For an airbag to work, both the inflator and the control system need to be fully functional.
Ultimately, you’ll never quite know if your airbags are going to work until they do… or don’t. But the best indications we have are that the majority of automotive airbags are proving functional and reliable over long periods of time. There may be a day sometime soon when we learn that those old airbags from the 1980s and 1990s are no longer to be trusted, and that will be the time to start dealing more carefully with vehicles of that vintage. For now, though, it seems the safest move is to leave well enough alone, and trust that even a decades-old airbag will still do the job safely and effectively.
2026-02-23 20:00:52
Even entry-level oscilloscopes today have simple math functions such as adding or subtracting two channels. But as [Arthur Pini] notes, more advanced scopes can now even do integration and differentiation. He writes about using these tools to make measurements on capacitors and inductors. The post in EDN is worth a read, even if your scope doesn’t offer this sort of math yet.
It makes sense that capacitors and inductors would benefit from this feature. After all, the current through a capacitor, for example, is proportional to the rate of change in the voltage across it. That’s a derivative. Since the scope can measure voltages, it can also differentiate to find the current.
The same idea applies to inductors, where the current through an inductor is related to the integral of the voltage across it. It is a simple matter to measure the voltages and perform an integration to determine the current.
All of this, of course, relates to differential equations and calculus. While calculus has a reputation for being hard, it actually makes sense if you want to work with quantities that change over time. Once you realize that a sine wave is just a fixed spot on a rotating wheel, everything comes together nicely. You could, of course, grab discrete samples from any scope and use numerical methods to get the same results. But it is much easier if your scope can do it for you.
2026-02-23 17:00:52
For a little over two thousand years, the primary light sources after the sun had set were oil lamps and candles. This was well before the age of fossil fuels, so these oil lamps were often fueled with a labor-intensive agricultural product like olive oil. Candles were similarly difficult to make, made from tallow, beeswax, or even butter. Labor and materials costs aside, though, there’s a surprising amount of energy in these fuels and [Maciej Nowak Projects] has a generator that help these ancient light sources generate some electricity on the side.
The generator is based around a piece of technology called a thermoelectric generator (TEG), which produces a voltage potential when placed in a temperature gradient. These aren’t new technologies, but their typically low efficiencies limit where they can be effectively used. In this case, however, [Maciej Nowak] has gone to great effort to boost this efficiency as high as possible by using a huge radiator on the cool side of the TEG and another one on the hot side, which in this case is heated by a small tea candle. The electricity produced is sent to a tiny DC converter which regulates the voltage to 3.3V, which then powers two custom-built pedestal lamps on either side of the TEG, each with a high-efficiency LED mounted to a custom-made circuit board.
Although this is certainly not the first time a TEG has been set up to run a small lighting system, we do appreciate this one for its polish, design, and high efficiency. It would make a fitting addition to anyone’s emergency power outage kit as it really increases the amount of available light produced from any given candle. When taken to the extreme, though, thermoelectric generators can be made to produce a surprising amount of energy, provided they are placed in the right environment.
