Weekly Roundup 1/28/12

January 28, 2012 by 1 Comment


Another week has passed and it is time to review the best of what hit our blog in the past week.

In first place is a repeat from last week showing how you can turn an Android device with a CMOS camera into a radiation detector.

In first place if we ignore repeats is a post about how the Raspberry Pi board can decode 1080p video! We’re just itching to get our grubbly little hands on some of these guys when they are finally released.

Up next is a project from one of our own. This week [Brian Benchoff] put up a post about how he built a manifold clock after seeing a similar project on Kickstarter.

Following that is a post showing how you can overlay video onto an encrypted HDMI signal. The MPAA would probably like to crack [bunnie] over the knuckles with a ruler for this one but he actually isn’t decrypting anything. Instead, he is encrypting the overlay and just replacing the normal video with it.

We like this next one a lot because it not only is a nice hack but it allows you to subtly control what can and cannot happen around you. Specifically, you can jam remote control helicopters with this device. It probably wouldn’t be too hard to pair this up with a TV B Gone to keep people from turning the TV back on once you have wrought your mischief.

Finally, another really neat one for you. In this post, we show [Sprite_tm’s] radio transmitter that is composed out of two button cell batteries, two lengths of wire and an ATtiny processor. It is amazing that this even works but with the right tools, a good hacker can do just about anything.

Geiger Counter Built In An Ohmmeter Enclosure

April 7, 2011 by 4 Comments

Here’s a Geiger Counter that makes itself at home inside of an old Ohmmeter (translated). [Anilandro] set out to built this radiation detector in order to learn how they work. Like other diy Geiger Counter builds we’ve seen, this project assembles a circuit to interface with a gas-filled tube which serves as the detector. [Anilandro] takes a few paragraphs to discuss how this works; the Geiger tube is basically a capacitor whose electrical characteristics change as an ionizing particle passes through it.

Once he had the theory worked out he scavenged some parts to use. A broken emergency light donated its transformer to provide the high voltage needed. The rest of the circuit was built on some protoboard, and a speaker was added to output the clicking noises that have become a familiar part of the detector hardware. The tube itself is housed in a wand that attaches to the base unit through a cable. Check out some test footage of the finished unit after the break.

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Hackable Geiger Counter

October 21, 2009 by 41 Comments

SFE_Geiger_Counter

[Aaron] A.K.A. [A1ronzo] at SparkFun has put together a hackable USB Geiger Counter. In his tutorial, he gets the Geiger counter to work as a random number generator. Later, he analyzes and discusses how well it works as a random number generator.  In the past, we have seen a number of radiation detectors hacks such as the Mr. Fission digital Geiger counter, a count accumulator, and a Polonium detecting pen,  Besides our inital thoughts of speeding up the number generation, and using it as a special character device, what else can you come up with to do with this device?

Catching The BOAT: Gamma-Ray Bursts And The Brightest Of All Time

September 18, 2024 by 12 Comments

Down here at the bottom of our ocean of air, it’s easy to get complacent about the hazards our universe presents. We feel safe from the dangers of the vacuum of space, where radiation sizzles and rocks whizz around. In the same way that a catfish doesn’t much care what’s going on above the surface of his pond, so too are we content that our atmosphere will deflect, absorb, or incinerate just about anything that space throws our way.

Or will it? We all know that there are things out there in the solar system that are more than capable of wiping us out, and every day holds a non-zero chance that we’ll take the same ride the dinosaurs took 65 million years ago. But if that’s not enough to get you going, now we have to worry about gamma-ray bursts, searing blasts of energy crossing half the universe to arrive here and dump unimaginable amounts of energy on us, enough to not only be measurable by sensitive instruments in space but also to effect systems here on the ground, and in some cases, to physically alter our atmosphere.

Gamma-ray bursts are equal parts fascinating physics and terrifying science fiction. Here’s a look at the science behind them and the engineering that goes into detecting and studying them.

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Small Mammals Appear To Have A Secret Infrared Sense

July 22, 2024 by 23 Comments

If you’ve ever watched Predator, you’ve noted the tactical advantage granted to the alien warrior by its heat vision. Indeed, even with otherwise solid camoflauge, Dutch and his squad ended up very much the hunted.

And yet, back in reality, it seems the prey might be the one with the ability to sense in the infrared spectrum. Research has now revealed this unique ability may all be down to the hairs on the back of some of the smallest mammals.

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Gamma Ray Spectroscopy The Pomelo Way

June 5, 2024 by 15 Comments

Depending on the circumstances you find yourself in, a Geiger counter can be a tremendously useful tool. With just a click or a chirp, it can tell you if any invisible threats lurk. But a Geiger counter is a “yes or no” instrument; it can only tell you if an ionizing event occurred, revealing nothing about the energy of the radiation. For that, you need something like this gamma-ray spectroscope.

Dubbed the Pomelo by [mihai.cuciuc], the detector is a homebrew solid-state scintillation counter made from a thallium-doped cesium iodide crystal and a silicon photomultiplier. The scintillator is potted in silicone in a 3D printed enclosure, to protect the hygroscopic crystal from both humidity and light. There’s also a temperature sensor on the detector board for thermal compensation. The Pomelo Core board interfaces with the physics package and takes care of pulse shaping and peak detection, while a separate Pomelo Zest board has an ESP32-C6, a small LCD and buttons for UI, SD card and USB interfaces, and an 18650 power supply. Plus a piezo speaker, because a spectroscope needs clicks, too.

The ability to determine the energy of incident photons is the real kicker here, though. Pomelo can detect energies from 50 keV all the way up to 3 MeV, and display them as graphs using linear or log scales. The short video below shows the Pomelo in use on samples of radioactive americium and thorium, showing different spectra for each.

[mihai.cuciuc] took inspiration for the Pomelo from this DIY spectrometer as well as the CosmicPi.

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Mining And Refining: Uranium And Plutonium

April 24, 2024 by 40 Comments

When I was a kid we used to go to a place we just called “The Book Barn.” It was pretty descriptive, as it was just a barn filled with old books. It smelled pretty much like you’d expect a barn filled with old books to smell, and it was a fantastic place to browse — all of the charm of an old library with none of the organization. On one visit I found a stack of old magazines, including a couple of Popular Mechanics from the late 1940s. The cover art always looked like pulp science fiction, with a pipe-smoking father coming home from work to his suburban home in a flying car.

But the issue that caught my eye had a cover showing a couple of rugged men in a Jeep, bouncing around the desert with a Geiger counter. “Build your own uranium detector,” the caption implored, suggesting that the next gold rush was underway and that anyone could get in on the action. The world was a much more optimistic place back then, looking forward as it was to a nuclear-powered future with electricity “too cheap to meter.” The fact that sudden death in an expanding ball of radioactive plasma was potentially the other side of that coin never seemed to matter that much; one tends to abstract away realities that are too big to comprehend.

Things are more complicated now, but uranium remains important. Not only is it needed to build new nuclear weapons and maintain the existing stockpile, it’s also an important part of the mix of non-fossil-fuel electricity options we’re going to need going forward. And getting it out of the ground and turned into useful materials, including its radioactive offspring plutonium, is anything but easy.

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