X-Rays From An Overdriven Magnetron

April 28, 2025 by Dan Maloney 34 Comments

If you say that you’re “nuking” something, pretty much everyone will know that you mean you’re heating something in the microwave. It’s technically incorrect, of course, as the magnetron inside the oven emits only non-ionizing radiation, and is completely incapable of generating ionizing radiation such as X-rays. Right?

Perhaps not, as these experiments with an overdriven magnetron suggest. First off, this is really something you shouldn’t try; aside from the obvious hazards that attend any attempt to generate ionizing radiation, there are risks aplenty here. First of all, modifying magnetrons as [SciTubeHD] did here is risky thanks to the toxic beryllium they contain, and the power supply he used, which features a DIY flyback transformer we recently featured, generates potentially dangerous voltages. You’ve been warned.

For the experiment, [SciTubeHD] stripped the magnets off a magnetron and connected his 40-kV AC power supply between the filament and the metal case of the tube. We’re not completely clear to us how this creates X-rays, but it appears to do so given the distinctive glow given off by an intensifying screen harvested from an old medical X-ray film cassette. The light is faint, but there’s enough to see the shadows of metallic objects like keys and PCBs positioned between the tube and the intensifying screen.

Are there any practical applications for this? Probably not, especially considering the potential risks. But it’s still pretty cool, and we’re suitably impressed that magnetrons can be repurposed like this.

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To See Within: Detecting X-Rays

April 23, 2025 by Dan Maloney 19 Comments

It’s amazing how quickly medical science made radiography one of its main diagnostic tools. Medicine had barely emerged from its Dark Age of bloodletting and the four humours when X-rays were discovered, and the realization that the internal structure of our bodies could cast shadows of this mysterious “X-Light” opened up diagnostic possibilities that went far beyond the educated guesswork and exploratory surgery doctors had relied on for centuries.

The problem is, X-rays are one of those things that you can’t see, feel, or smell, at least mostly; X-rays cause visible artifacts in some people’s eyes, and the pencil-thin beam of a CT scanner can create a distinct smell of ozone when it passes through the nasal cavity — ask me how I know. But to be diagnostically useful, the varying intensities created by X-rays passing through living tissue need to be translated into an image. We’ve already looked at how X-rays are produced, so now it’s time to take a look at how X-rays are detected and turned into medical miracles.

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Hackaday Links: April 13, 2025

April 13, 2025 by Dan Maloney 9 Comments

It’s been a while since we’ve dunked on an autonomous taxi foul-up, mainly because it seemed for a while there that most of the companies field testing driverless ride-sharing services had either ceased operation or curtailed them significantly. But that appears not to be the case after a Waymo robotaxi got stuck in a Chick-fil-A drive-through. The incident occurred at the chicken giant’s Santa Monica, California location at about 9:30 at night, when the autonomous Jaguar got stuck after dropping off a passenger in the parking lot. The car apparently tried to use the drive-through lane to execute a multi-point turn but ended up across the entrance, blocking other vehicles seeking their late-evening chicken fix. The drive-through-only restaurant ended up closing for a short time while Waymo figured out how to get the vehicle moving again.

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You Shouldn’t Build An X-Ray Machine, But You Could

April 9, 2025 by Al Williams 18 Comments

Ever wanted your own X-ray machine? Of course you have! Many of us were indoctrinated with enticing ads for X-ray specs and if you like to see what’s inside things, what’s better than a machine that looks inside things? [Hyperspace Pirate] agrees, and he shows you the dangers of having your own X-ray machine in the video below.

The project starts with an X-ray tube and a high voltage supply. The tube takes around 70,000 volts which means you need a pretty stout supply, an interesting 3D printed resistor, and some mineral oil.

The output display? A normal camera. You also need an intensifying screen, which is just a screen with phosphor or something similar. He eventually puts everything in lead and reminds you that this is a very dangerous project and you should probably skip it unless you are certain you know how to deal with X-ray dangers.

Overall, looks like a fun project. But if you want real credit, do like [Harry Simmons] and blow your own X-ray tube, too. We see people build similar machines from time to time. You shouldn’t, but if you do, remember to be careful and to tell us about it!

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Sealed Packs Of Pokémon Cards Give Up Their Secrets Without Opening Them

July 20, 2024 by Donald Papp 32 Comments

[Ahron Wayne] succeeded in something he’s been trying to accomplish for some time: figuring out what’s inside a sealed Pokémon card packet without opening it. There’s a catch, however. It took buying an X-ray CT scanner off eBay, refurbishing and calibrating it, then putting a load of work into testing and scanning techniques. Then finally combining the data with machine learning in order to make useful decisions. It’s a load of work but [Ahron] succeeded by developing some genuinely novel techniques.

While using an X-ray machine to peek inside a sealed package seems conceptually straightforward, there are in fact all kinds of challenges in actually pulling it off. There’s loads of noise. So much that the resulting images give a human eyeball very little to work with. Luckily, there are also some things that make the job a little easier.

For example, it’s not actually necessary to image an entire card in order to positively identify it. Teasing out the individual features such as a fist, a tentacle, or a symbol are all useful to eliminate possibilities. Interestingly, as a side effect the system can easily spot counterfeit cards; the scans show up completely different.

When we first covered [Ahron]’s fascinating journey of bringing CT scanners back to life, he was able to scan cards but made it clear he wasn’t able to scan sealed packages. We’re delighted that he ultimately succeeded, and also documented the process. Check it out in the video below.

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Danger Is My Middle Name

June 29, 2024 by Elliot Williams 75 Comments

Last week, [Al Williams] wrote up a his experience with a book that provided almost too much detailed information on how to build a DIY x-ray machine for his (then) young soul to bear. He almost had to build it! Where the “almost” is probably both a bummer because he didn’t have an x-ray machine as a kid, but also a great good because it was a super dangerous build, of a typical sort for the 1950s in which it was published.

Part of me really loves the matter-of-factness with which “A Boy’s First Book of Linear Accelerators” tells you how you (yes you!) can build a 500 kV van der Graff generator. But at the same time, modern me does find the lack of safety precautions in many of these mid-century books to be a little bit spooky. Contrast this with modern books where sometimes I get the feeling that the publisher’s legal team won’t let us read about folding paper airplanes for fear of getting cut.

A number of us have built dangerous projects in our lives, and many of us have gotten away with it. Part of the reason that many of us are still here is that we understood the dangers, but I would be lying if I said that I always fully understood them. But thinking about the dangers is still our first and best line of defense. Humility about how well you understand all of the dangers of a certain project is also very healthy – if you go into it keeping an eye out for the unknown unknowns, you’re in better shape.

Safety isn’t avoiding danger, but rather minimizing it. When we publish dangerous hacks, we really try to at least highlight the most important hazards so that you know what to look out for. And over the years, I’ve learned a ton of interesting safety tricks from the comments and fellow hackers alike. My ideal, then, is the spirit of the 1950s x-ray book, which encourages you to get the hack built, but modernized so that it tells you where the dangers lie and how to handle them. If you’re shooting electrons, shouldn’t the book also tell you how to stay out of the way?

Artist rendition of the Chandra telescope system in deep space. (Credit: NASA / James Vaughn)

The Chandra X-Ray Observatory Faces Shutdown In FY2025 Budget

March 18, 2024 by Maya Posch 30 Comments

The Chandra X-ray Observatory started its mission back in 1999 when Space Shuttle Columbia released it from its payload bay. Originally, it was supposed to serve only a five-year mission, but it has managed twenty-four years so far and counting, providing invaluable science along with the other Great Observatory: the Hubble Space Telescope. Unfortunately, NASA’s FY2025 budget now looks to threaten all space telescopes and Chandra in particular. This comes as part of the larger FY2025 US budget, which sees total funding for NASA increase by 2%, but not enough to prevent cuts in NASA’s space telescope operations.

NASA already anticipated this cut in 2023, with funding shifting to the Nancy Grace Roman Space Telescope (infrared spectrum, scheduled for 2027). Since Hubble is a joint operation with ESA, any shortfalls might be caught this way, but Chandra’s budget will go from 68.3M USD in FY2023 to 41.4M USD in FY2025 and from there plummeting to 5.2M USD by FY2029, effectively winding down the project and ending NASA’s flagship X-ray astronomy mission. This doesn’t sit well with everyone, with a website called Save Chandra now launched to petition the US government to save the observatory, noting that it still has a decade of fuel for its thrusters remaining and it also has stable mission costs.

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