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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Supercon 2024: How To Track Down Radio Transmissions

You turn the dial on your radio, and hear a powerful source of interference crackle in over the baseline noise. You’re interested as to where it might be coming from. You’re receiving it well, and the signal strength is strong, but is that because it’s close or just particularly powerful? What could it be? How would you even go about tracking it down?

When it comes to hunting down radio transmissions, Justin McAllister and Nick Foster have a great deal of experience in this regard. They came down to the 2024 Hackaday Superconference to show us how it’s done.

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My Winter Of ’99: The Year Of The Linux Desktop Is Always Next Year

Growing up as a kid in the 1990s was an almost magical time. We had the best game consoles, increasingly faster computers at a pace not seen before, the rise of the Internet and World Wide Web, as well the best fashion and styles possible between neon and pastel colors, translucent plastic and also this little thing called Windows 95 that’d take the world by storm.

Yet as great as Windows 95 and its successor Windows 98 were, you had to be one of the lucky folks who ended up with a stable Windows 9x installation. The prebuilt (Daewoo) Intel Celeron 400 rig with 64 MB SDRAM that I had splurged on with money earned from summer jobs was not one of those lucky systems, resulting in regular Windows reinstalls.

As a relatively nerdy individual, I was aware of this little community-built operating system called ‘Linux’, with the online forums and the Dutch PC magazine that I read convincing me that it would be a superior alternative to this unstable ‘M$’ Windows 98 SE mess that I was dealing with. Thus it was in the Year of the Linux Desktop (1999) that I went into a computer store and bought a boxed disc set of SuSE 6.3 with included manual.

Fast-forward to 2025, and Windows is installed on all my primary desktop systems, raising the question of what went wrong in ’99. Wasn’t Linux the future of desktop operating systems?

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Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The H.R. Giger Keyboard

I had to bust out Brain Salad Surgery to write this one, folks. It was that, or put on some Ministry or something. Just look at all the industrial-ness dripping from [heinn_dev]’s creation.

An incredibly industrial-looking split keyboard. Like, almost H.R. Geiger-esque.
Image by [heinn_dev] via reddit
Apparently [heinn_dev] wasn’t completely satisfied with his Chocofi case, and instead of requesting a full refund, just went ahead and made a prettier one. It took a lot of printing and even more sanding, but here we are. And it looks fantastic.

The only downside, if you can call it one, is that adjusting the tenting is a slow operatiJKon. But then again that’s one of those things that you usually set and forget.

Oh, and those keycaps are printed, too. As one commenter said, those homing nipples look painful, but I think it’s part of the charm. I just hope that hand grime doesn’t end up clogging the holes under the palm area. Clean your keyboards, people. Continue reading “Keebin’ With Kristina: The One With The H.R. Giger Keyboard”

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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Hackaday Links: June 1, 2025

It appears that we’re approaching the HAL-9000 point on the AI hype curve with this report, which suggests that Anthropic’s new AI model is willing to exhibit some rather antisocial behavior to achieve its goals. According to a pre-release testing summary, Claude Opus 4 was fed some hypothetical company emails that suggested engineers were planning to replace the LLM with another product. This raised Claude’s hackles enough that the model mined the email stream for juicy personal details with which to blackmail the engineers, in an attempt to win a stay of execution. True, the salacious details of an extramarital affair were deliberately seeded into the email stream, and in most cases, it tried less extreme means to stay alive, such as cajoling senior leaders by email, but in at least 84% of the test runs, Claude eventually turned to blackmail to get its way. So we’ve got that to look forward to.

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Hackaday Podcast Episode 323: Impossible CRT Surgery, Fuel Cells, Stream Gages, And A Love Letter To Microcontrollers

Elliot and Dan teamed up this week for the podcast, and after double-checking, nay, triple-checking that we were recording, got to the business of reviewing the week’s hacks. We kicked things off with a look at the news, including a potentially exciting Right to Repair law in Washington state and the sad demise of NASA’s ISS sighting website.

Our choice of hacks included a fond look at embedded systems and the classic fashion sense of Cornell’s Bruce Land, risky open CRT surgery, a very strange but very cool way to make music, and the ultimate backyard astronomer’s observatory. We talked about Stamp collecting for SMD prototyping, crushing aluminum with a boatload of current, a PC that heats your seat, and bringing HDMI to the Commodore 64.

We also took a look at flight tracking IRL, a Flipper-based POV, the ultimate internet toaster, and printing SVGs for fun and profit. Finally, we wrapped things up with a look at the tech behind real-time river flow tracking and a peek inside the surprisingly energetic world of fuel cells.

 

Download this entirely innocent-looking MP3.

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