There was a recent recall of so-called ‘radioactive shrimp’ that were potentially contaminated with cesium-137 (Cs-137). But contamination isn’t an all-or-nothing affair, so you might wonder exactly how hot the shrimp were. As it turns out, the FDA’s report makes clear that the contamination was far below the legal threshold for Cs-137. In addition, not […]
Have you heard of the Sprengel pump? It’s how they drew hard vacuum back before mechanical pumps were perfected — the first light bulbs had their vacuums drawn with Sprengel pumps, for example. It worked by using droplets of a particular liquid to catch air particles, and push them out a narrow tube, thereby slowly […]
A Meshtastic node has been one of the toys of the moment over the last year, and since they are popular with radio amateurs there’s a chance you’ll already live within range of at least one. They can typically run from a lithium-ion or li-po battery, so it’s probable that like us you’ve toyed with […]
When Deluxe Paint came out with the original Amiga in 1985, it was the killer app for the platform. [Christopher Drum] starts his recent article on just that note, remembering the day he and his mother walked into a computer store, and walked out with a brand new Amiga… thanks entirely to Deluxe Paint. Forty […]
A new kind of ‘camera’ is poking at the invisible world of the human body – and it’s made from the same weird crystals that once shook up solar energy. Researchers at Northwestern University and Soochow University have built the first perovskite-based gamma-ray detector that actually works for nuclear medicine imaging, like SPECT scans. This […]
Why build a telescope? YOLO, as the kids say. Having decided that, one must decide what type of far-seer one will construct. For his 10″ reflector, [Carl Anderson] once again said “Yolo”— this time not as a slogan, but in reference to a little-known type of reflecting telescope. Telescope or sci-fi laser gun? YOLO, just […]
A laptop is one of the greatest tools at the disposal of a hacker. They come in all manner of shapes and sizes with all manner of features. But perhaps the greatest limit held by all laptops is their chiclet keyboard. While certainly serviceable, a proper mechanical keyboard will always reign supreme, which is why […]
For most people, experimentation with film photography comes in the form of the 35 mm format. Its ubiquity in snapshot photography means cameras are readily available at all levels, and the film offers a decent compromise between resolution and number of shots per dollar spent. For those who wish to take their film photography further […]
In theory, all parts are ideal and do just exactly what they say on the box. In practice, everything has its limits, most components have non-ideal characteristics, and you can even turn most parts’ functionality upside down. The Component Abuse Challenge celebrates the use of LEDs as photosensors, capacitors as microphones, and resistors as heat […]
If you take the wheels off a FIAT Punto, you might just notice that those rims fit nicely on a rail. [AT Lab] did, and the resulting build makes for a very watchable video. Some of us have been known to spend a little too much time chasing trains, and there’s little on rails that […]