Screens Of Death: From Diagnostic Aids To A Sad Emoji

There comes a moment in the life of any operating system when an unforeseen event will tragically cut its uptime short. Whether it’s a sloppily written driver, a bug in the handling of an edge case or just dumb luck, suddenly there is nothing more that the OS’ kernel can do to salvage the situation. With its last few cycles it can still gather some diagnostic information, attempt to write this to a log or memory dump and then output a supportive message to the screen to let the user know that the kernel really did try its best.

This on-screen message is called many things, from a kernel panic message on Linux to a Blue Screen of Death (BSOD) on Windows since Windows 95, to a more contemplative message on AmigaOS and BeOS/Haiku. Over the decades these Screens of Death (SoD) have changed considerably, from the highly informative screens of Windows NT to the simplified BSOD of Windows 8 onwards with its prominent sad emoji that has drawn a modicum of ridicule.

Now it seems that the Windows BSOD is about to change again, and may not even be blue any more. So what’s got a user to think about these changes? What were we ever supposed to get out of these special screens?

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High-Stakes Fox Hunting: The FCC’s Radio Intelligence Division In World War II

With few exceptions, amateur radio is a notably sedentary pursuit. Yes, some hams will set up in a national or state park for a “Parks on the Air” activation, and particularly energetic operators may climb a mountain for “Summits on the Air,” but most hams spend a lot of time firmly planted in a comfortable chair, spinning the dials in search of distant signals or familiar callsigns to add to their logbook.

There’s another exception to the band-surfing tendencies of hams: fox hunting. Generally undertaken at a field day event, fox hunts pit hams against each other in a search for a small hidden transmitter, using directional antennas and portable receivers to zero in on often faint signals. It’s all in good fun, but fox hunts serve a more serious purpose: they train hams in the finer points of radio direction finding, a skill that can be used to track down everything from manmade noise sources to unlicensed operators. Or, as was done in the 1940s, to ferret out foreign agents using shortwave radio to transmit intelligence overseas.

That was the primary mission of the Radio Intelligence Division, a rapidly assembled organization tasked with protecting the United States by monitoring the airwaves and searching for spies. The RID proved to be remarkably effective during the war years, in part because it drew heavily from the amateur radio community to populate its many field stations, but also because it brought an engineering mindset to the problem of finding needles in a radio haystack.

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The Potential Big Boom In Every Dust Cloud

To the average person, walking into a flour- or sawmill and seeing dust swirling around is unlikely to evoke much of a response, but those in the know are quite likely to bolt for the nearest exit at this harrowing sight. For as harmless as a fine cloud of flour, sawdust or even coffee creamer may appear, each of these have the potential for a massive conflagration and even an earth-shattering detonation.

As for the ‘why’, the answer can be found in for example the working principle behind an internal combustion engine. While a puddle of gasoline is definitely flammable, the only thing that actually burns is the evaporated gaseous form above the liquid, ergo it’s a relatively slow process; in order to make petrol combust, it needs to be mixed in the right air-fuel ratio. If this mixture is then exposed to a spark, the fuel will nearly instantly burn, causing a detonation due to the sudden release of energy.

Similarly, flour, sawdust, and many other substances in powder form will burn gradually if a certain transition interface is maintained. A bucket of sawdust burns slowly, but if you create a sawdust cloud, it might just blow up the room.

This raises the questions of how to recognize this danger and what to do about it.

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Forced E-Waste PCs And The Case Of Windows 11’s Trusted Platform

Until the release of Windows 11, the upgrade proposition for Windows operating systems was rather straightforward: you considered whether the current version of Windows on your system still fulfilled your needs and if the answer was ‘no’, you’d buy an upgrade disc. Although system requirements slowly crept up over time, it was likely that your PC could still run the newest-and-greatest Windows version. Even Windows 7 had a graphical fallback mode, just in case your PC’s video card was a potato incapable of handling the GPU-accelerated Aero Glass UI.

This makes a lot of sense, as the most demanding software on a PC are the applications, not the OS. Yet with Windows 11 a new ‘hard’ requirement was added that would flip this on its head: the Trusted Platform Module (TPM) is a security feature that has been around for many years, but never saw much use outside of certain business and government applications. In addition to this, Windows 11 only officially supports a limited number of CPUs, which risks turning many still very capable PCs into expensive paperweights.

Although the TPM and CPU requirements can be circumvented with some effort, this is not supported by Microsoft and raises the specter of a wave of capable PCs being trashed when Windows 10 reaches EOL starting this year.

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Remotely Interesting: Stream Gages

Near my childhood home was a small river. It wasn’t much more than a creek at the best of times, and in dry summers it would sometimes almost dry up completely. But snowmelt revived it each Spring, and the remains of tropical storms in late Summer and early Fall often transformed it into a raging torrent if only briefly before the flood waters receded and the river returned to its lazy ways.

Other than to those of us who used it as a playground, the river seemed of little consequence. But it did matter enough that a mile or so downstream was some sort of instrumentation, obviously meant to monitor the river. It was — and still is — visible from the road, a tall corrugated pipe standing next to the river, topped with a box bearing the logo of the US Geological Survey. On occasion, someone would visit and open the box to do mysterious things, which suggested the river was interesting beyond our fishing and adventuring needs.

Although I learned quite early that this device was a streamgage, and that it was part of a large network of monitoring instruments the USGS used to monitor the nation’s waterways, it wasn’t until quite recently — OK, this week — that I learned how streamgages work, or how extensive the network is. A lot of effort goes into installing and maintaining this far-flung network, and it’s worth looking at how these instruments work and their impact on everyday life.

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EMF Forming Was A Neat Aerospace Breakthrough

Typically, when we think about forming metal parts, we think about beating them with hammers, or squeezing them with big hydraulic presses. But what if magnets could do the squeezing? As it turns out—Grumman Aerospace discovered they can, several decades ago! Even better, they summed up this technique in a great educational video which we’ve placed below the break.

The video concerns the development of the Grumman EMF Torque Tube. The parts are essentially tubes with gear-like fittings mounted in either end, which are fixed with electromagnetic forming techniques instead of riveting or crimping. Right away, we’re told the key benefits—torque tubes built this way are “stronger, lighter, and more fatigue resistant” than those built with conventional techniques. Grumman used these torque tubes in such famous aircraft as the F-14 Tomcat, highlighting their performance and reliability.

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A Brief History Of Fuel Cells

If we asked you to think of a device that converts a chemical reaction into electricity, you’d probably say we were thinking of a battery. That’s true, but there is another device that does this that is both very similar and very different from a battery: the fuel cell.

In a very simple way, you can think of a fuel cell as a battery that consumes the chemicals it uses and allows you to replace those chemicals so that, as long as you have fuel, you can have electricity. However, the truth is a little more complicated than that. Batteries are energy storage devices. They run out when the energy stored in the chemicals runs out. In fact, many batteries can take electricity and reverse the chemical reaction, in effect recharging them. Fuel cells react chemicals to produce electricity. No fuel, no electricity.

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