This is a Geiger counter which charts its readings on a webpage. [Radu Motisan] put a lot of time into the build and it shows. This thing is packed with features and the hardware choices were the best combinations found through several iterations of development.
In addition to radiation levels the sensor unit takes several other measurements. These include temperature, humidity, luminosity, and barometric pressure. All of the sensor data is monitored and gathered by an ATmega168 which can be charted on a webpage with the help of an ENC28J60 Ethernet chip. The collection and display of this data is detailed at the post linked above.
For those interested in the hardware development, [Radu] published many updates along the way. These are available in his forums posts, as well as his build log. He doesn’t have any videos of his recent work, but way back in May he did publish a clip (found after the break) which shows the testing of different Geiger tubes.
Continue reading “Online radiation monitoring station”
Have a little class when you’re screening for radioactive particles. You can follow the example which [Moustachenator] has set with this gorgeous Geiger counter case.
The business end includes the same Geiger tube we see in all of these projects, but he took the time to solder together a tidy circuit board and housed it in an acrylic tube. it connects to the base unit using a springy telephone handset cord. The laser cut walnut enclosure offers plenty of room for the ATX power supply hidden inside. This feeds the Arduino which runs the system, and provides a powerful source for the Nixie tubes which serve as the display. The attention to detail when it came time to assemble the case is what lends an antique look to the project, even though everything was built from the ground up. Check out the video after the break to see a brief demonstration.
Continue reading “Beautifully crafted Geiger counter a must if you live in a hot zone”
[Thomas] took a Geiger counter he built on a plane. Why? Because he can, much to the chagrin of airport security.
[Thomas]’ Geiger counter is built around an old Russian SBT-10A detector containing ten separate Geiger tubes. This tube was connected to a circuit containing a LiPo battery, a few high-voltage components, and an audio jack connected to the tubes themselves. When alpha, beta, or gamma radiation hits one of the Geiger tubes, an enormous click is sent to the audio jack and into the microphone jack of a small netbook.
Right after boarding a plane in Dublin, [Thomas] booted up his computer, started recording in Audacity, plugged in his Geiger counter, and stored his experiment safely in the overhead compartment. After landing in Prague a few hours later, [Thomas] saved the 247 MB .WAV file and began working on a way to convert clicks in an audio track into usable data.
The audio output on the Geiger counter overloaded the mic input on his netbook, making ‘event detection’ very easy with a small C app. After plotting all the data (seen above), [Thomas] had a complete record of the radiation on his 2-hour flight.
Because there was far less atmosphere to absorb cosmic radiation, [Thomas]’ radiation dose was 9.1 microsieverts. Much more than at sea level, but nothing even air crews need to worry about.
What do you do if you have 18 Geiger tubes lying around? [Robert] had an interesting idea to build a cosmic ray detector and hodoscope to observe the path cosmic rays take while flying through his lab.
[Robert]’s cosmic ray detector works by detecting the output 9 Geiger tubes on the y-axis and 9 Geiger tubes on the x-axis with a coincidence circuit. When a cosmic ray flies through the detector, it should trigger two tubes simultaneously. By graphing which of the two tubes were triggered on an array of 81 LEDs, [Robert] not only knows when a cosmic ray is detected, but where the cosmic ray was.
The detectors do pick up a little background radiation, but thanks to [Robert]’s coincidence circuit, he can be fairly certain that what he’s recording are actually high-energy cosmic rays.
Before building the 9×9 hodoscope, [Robert] built a similar drift hodoscope that simply plots the path a cosmic ray takes through an array of Geiger tubes. You can check out videos of both these cosmic ray detectors after the break.
Continue reading “Detecting cosmic rays with 18 Geiger tubes”
[Jeff Keyser] from mightyohm.com got a chance to show off this interesting take on ambient music. He’s using his geiger counter kit to detect beta and gamma radiation. This then sends a pulse down the line to an Arduino to turn it into a musical note. The geiger counters put out a 1.ms 3v pulse though, so he first has to run this through a 74Ls04, which spits out the 5V the arduino wants. He’s admittedly no musician, but you can hear in the video it sounds fine. Especially considering they are all just C in different octaves. Those of us that are musicians probably would have gone with a B#.
The ambient noise is interesting, but when you realize it is due to radioactive decay, it becomes somehow more attention getting. We often forget about the invisible world around us. He even drops a few Uranium marbles onto the geiger counters to spice things up.
Continue reading “Making music with radiation”
It’s really amazing what you can find at military surplus shops. [David] just built a radiation detector out of a DT-590A scintillation probe originally made to test if Air Force bases were contaminated with Plutonium. Who says nothing good came out of massive nuclear arsenals?
DT-590A / PDR-56 Gamma ray probes were made obsolete by the US Air Force a few years ago and they’re trickling into military surplus stores around the country and the Internet. [David] found the manual for this probe and put together a little circuit to drive this x-ray sensor. The build uses an ammeter as a simple dial, and includes a piezo speaker for the prerequisite Geiger counter ‘clicks.’
[David] also threw up a post on converting this x-ray probe into a general purpose Gamma probe, effectively making it a Geiger counter for the really dangerous radiation. You could always use your smart phone for the same task, but recycling military hardware imparts a good bit of geek cred.
Next time you’re waiting in the security line in an airport, why don’t you pull out your smartphone and count all the radiation being emitted by those body scanners and x-rays? There’s an app for that, courtesy of Mr. [Rolf-Dieter Klein].
The app works by blocking all the light coming into a phone’s camera sensor with a piece of tape or plastic. Because high energy radiation will cause artifacts on the CMOS camera sensor inside the phone, radiation will be captured as tiny specks of white light. The title picture for this post was taken from a camera phone at the Helmholtz Research Center in Munich being bathed in 10 Sieverts per hour of Gamma radiation from the decay of Cesium-137.
We have to note that blips of ‘bad data’ from a CMOS camera sensor aren’t unusual. These can come from electrical weirdness in the sensor itself or even the heat from the battery. [Rolf]’s app takes a reading of the noise floor and subtracts it from the counter. Radioactive decay resulting in Beta particles such as the Potassium-40 in bananas or the Uranium in granite counter tops don’t really register, although [Rolf] did have some success with Potassium chloride and a long measurement time. Still though, it’s a really cool way to turn a phone into a tricorder.
Continue reading “Turn your camera phone into a Geiger counter”