A Cheap And Cheerful Geiger Counter Build

August 21, 2019 by 10 Comments

Hackers often have broad interests across the sciences, of which nuclear topics are no exception. The Geiger counter remains a popular build, and could be a handy tool to have in a time of rising tensions between nuclear powers. [Leonora Tindall] had tinkered with basic units, but wanted a better idea of actual radiation levels in her area. Thus began the build!

The project began by leveraging the Geiger counter kit from the Mighty Ohm. [Leonora] had built one of these successfully, but wished for a visual readout to supplement the foreboding ticking noises from the device. This was achieved by installing a Metro Mini microcontroller along with a 4-character, 14-segment alphanumeric display. This, along with the cardboard enclosure, makes the build look like a prop from an 80s hacker movie. Very fitting for the Cold War-era technology at work.

By using a pre-built kit and upgrading it with display hardware, [Leonora] now has readings at a glance without having to reinvent the wheel and design her own board from scratch. Of course, if you’re thinking of taking on a more complex build, you might consider a scintillation detector instead.

DIY Geiger Counter Is Sure To Generate Clicks

August 19, 2019 by 19 Comments

On the outside, a Geiger counter seems like a complicated thing. And you might think a device that detects a dangerous, mostly invisible threat like radiation should be complicated. But they’re actually pretty simple. The Geiger-Muller tube does most of the work, which boils down to detecting brief moments of conductivity caused by chain reactions of charged particles in radioactive materials.

[Prabhat_] wanted to build a unique-looking Geiger counter, and we’d say that this slick, Star Trek-esque result succeeds. A well-organized display shows the effective dose rate, counts per minute, and cumulative dose, which can be displayed in either microsieverts or millirems. We dig the 3D printed case design, because we like to see form follow function.

The counter is powered by an 18650 cell that’s DC-to-DC boosted to 400+ volts. A NodeMCU processes the signal coming in from the G-M tube and expresses it in both clicks and LED blinks, both of which can be toggled on or off from the home screen. The alert threshold can be customized in the settings, which means the point at which green changes to red.

Click-click-click past the break for [prabhat_]’s great walk-through video, where he tests it with uranium ore and a thoriated gas lantern mantle.

If you want to take the opposite approach and get to clicking ASAP, well, fire up your hot glue gun and dump out your scrap bin.

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Duck And Cover With This WiFi “Geiger Counter”

April 8, 2019 by 10 Comments

There’s perhaps no sound more recognizable than the frantic clicking of a Geiger counter. Not because this is some post-apocalyptic world in which everyone is personally acquainted with the operation of said devices, but because it’s such a common effect used in many movies, TV shows, and video games. If somebody hears that noise, even if it doesn’t really make sense in context, they know things are about to get serious.

Capitalizing on this phenomena, [Anton Haidai] has put together a quick hack which turns the ESP8266 into a “Geiger counter” for WiFi. Rather than detecting radiation, the gadget picks up on the strongest nearby WiFi signal and will start clicking in response to signal strength. As the signal gets stronger, so does the clicking. While primarily a novelty, it’s an interesting idea that could potentially be useful for things like fox hunting.

The hardware is really about as simple as it gets, just a basic buzzer attached to one of the digital pins on a NodeMCU development board. This project is more of a proof of concept, but if it were to be developed further it would be interesting to see the electronics placed into a 3D printed replica of one of the old Civil Defense Geiger counters. Perhaps even integrating an analog gauge that can bounce around in response to signal strength.

Software-wise there is the option of locking onto one single network SSID or allowing the device to find the strongest network in the area. Even if you’re not in the market for a chirping WiFi detector, the code is a good example of how you can detect signal RSSI and act on it accordingly; a neat trick which might come in handy in a future project.

If you’re more interested in the real thing, we’ve got plenty of DIY Geiger counters in the archive for you to check out. From diminutive builds that can be mounted to the top of a 9V battery to high-tech solid state versions with touch screen interfaces, you should have plenty of inspiration if you’re looking to kit yourself out before your next drive through the Chernobyl Exclusion Zone.

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The Ins And Outs Of Geiger Counters, For Personal Reasons

August 12, 2018 by 28 Comments

There are times in one’s life when circumstances drive an intense interest in one specific topic, and we put our energy into devouring all the information we can on the subject. [The Current Source], aka [Derek], seems to be in such a situation these days, and his area of interest is radioactivity and its measurement. So with time to spare on his hands, he has worked up this video review of radioactivity and how Geiger counters work.

Why the interest in radioactivity? Bluntly put, because he is radioactive, at least for the next week. You see, [Derek] was recently diagnosed with thyroid cancer, and one of the post-thyroidectomy therapeutic options to scavenge up any stray thyroid cells is drinking a cocktail of iodine-131, a radioisotope that accumulates in thyroid cells and kills them. Trouble is, this leaves the patient dangerously radioactive, necessitating isolation for a week or more. To pass the time away from family and friends, [Derek] did a teardown on a commercial Geiger counter, the classic Ludlum Model 2 with a pancake probe. The internals of the meter are surprisingly simple, and each stage of the circuit is easily identified. He follows that up with a DIY Geiger counter kit build, which is also very simple — just a high-voltage section made from a 555 timer along with a microcontroller. He tests both instruments using himself as a source; we have to say it’s pretty alarming to hear how hot he still is. Check it out in the video below.

Given the circumstances, we’re amazed that [Derek] is not only keeping his cool but exhibiting a good sense of humor. We wish him well in his recovery, and if doing teardowns like this or projects like this freezer alarm or a no-IC bipolar power supply helps him cope, then we all win.

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Fun-Size Geiger Counter Sits Atop A 9-Volt Battery

September 20, 2017 by 29 Comments

Want a little heads-up before walking into a potentially dangerous radioactive area? Sure, we all do. But the typical surplus Civil Defense Geiger counter is just too bulky to fit into the sleek, modern every-day carry of the smartphone age. So why not slim down your first line of defense against achieving mutant status with this tiny Geiger counter (Facebook)?

We jest about the use cases for a personal-sized Geiger counter, as [Ian King]’s inspiration for this miniaturized build was based more on a fascination with quantifying the unseen world around us. Details are thin in his post, but [Ian] kindly shared the backstory for this build with us. Working on a budget and mostly with spare parts, the big outlay in the BOM was $20 for a Soviet-era SBM-10 tube, itself a marvel of miniaturization. While waiting the two months needed for the tube to arrive, [Ian] whipped up a perf board circuit with a simple oscillator and a CFL transformer to provide the 400 volts needed for the tube. The whole circuit, complete with tiny speaker and an LED to indicate pulses, sits neatly on top of a 9-volt battery. The video below shows it in action with a test source.

Geiger counters are not exactly rare projects on Hackaday, and with good reason. Take a look at this no-solder scrap bin counter or this traveling GPS Geiger counter built dead-bug style.

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Roam The Wastelands With This Fallout-Themed Mini Geiger Counter

March 16, 2017 by 46 Comments

For anyone who has worked with radioactive materials, there’s something that’s oddly comforting about the random clicks of a Geiger counter. And those comforting clicks are exactly why we like this simple pocket Geiger counter.

Another good reason to like [Tim]’s build is the Fallout theme of the case. While not an item from the game, the aesthetic he went for with the 3D-printed case certainly matches the Fallout universe. The counter itself is based on the popular Russian SBT-11A G-M tubes that are floating around eBay these days. You might recall them from coverage of this minimalist Geiger counter, and if you were inspired to buy a few of the tubes, here’s your chance for a more polished build. The case is stuffed with a LiPo pack, HV supply, and a small audio amp to drive the speaker. The video below shows it clicking merrily from a calibration source.

We can see how this project could be easily expanded — a small display that can show the counts per minute would be a great addition. But there’s something about how pocketable this is, and just the clicking alone is enough for us.

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A No-Solder, Scrap-Bin Geiger Counter For $15

January 18, 2017 by 30 Comments

Scenario: your little three-hour boat tour runs into a storm, and you’re shipwrecked on a tropic island paradise. You’re pretty sure your new home was once a nuclear test site, but you have no way to check. Only your scrap bin, camera bag, and hot glue gun survived the wreck. Can you put together a Geiger-Müller counter from scrap and save the day?

Probably not, unless your scrap bin is unusually well stocked and contains a surplus Russian SI-3BG miniature Geiger tube, the heart of [GH]’s desert island build. These tubes need around 400 volts across them for incident beta particles or gamma rays to start the ionization avalanche that lets it produce an output pulse. [GH]’s build uses the flash power supply of a disposable 35mm camera to generate the high voltage needed, but you could try using a CCFL inverter, say. The output of the tube tickles the base of a small signal transistor and makes a click in an earbud for every pulse detected.

You’ll no doubt notice the gallons of hot glue, alligator clips, and electrical tape used in the build, apparently in lieu of soldering. While we doubt the long-term robustness of this technique, far be it from us to cast stones – [GH] shows us what you can accomplish even when you find yourself without the most basic of tools.

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