Flipper Zero Geiger Counter
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Geiger CounterFlipper ZeroRadiation Detection
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Geiger Counter
Flipper Zero
Radiation Detection
The Flipper Zero Geiger Counter module is a DIY project that integrates a Geiger counter with the Flipper Zero device, sparking discussions on its usefulness, safety, and comparison to other radiation detection devices.
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Yep, and even with AC, it depends on the frequency. There are a ton of variables affecting how dangerous electricity is to people, so it's hard to make general statements about it.
https://www.youtube.com/watch?v=BGD-oSwJv3E
But even beyond that, the maximum power output will still be pretty limited. If you short the HV rails, it will almost certainly start to drop in voltage and raise in current quickly, but only to the limits of the resistance from other elements in series and the power source's output ability. I strongly doubt you could even make something dangerous from the Flipper, at least unless you attach a large cap, let it charge slowly, and attach a taser module.
I would be rather surprised if a device that is powered off a lithium ion battery like the one in the Flipper Zero managed to seriously injure someone.
The thing to remember is the output impedance. You can have 1000's of volts at a node, but its sourced by a VERY high impedance output. so when you touch it with your hands (which is like 100kohm on a dry day), the voltage collapses because of the voltage divider your hand created.
But if the output impedance is low (transmission lines), well its game over.
That said, it's always prudent to treat any live electrical line as dangerous unless you know for a fact that it isn't, of course.
It's counterintuitive enough that the probes actually have an "anti-warning" label to inform people that they are safe to touch.
With low voltage battery circuits the main thing you have to be wary of is capacitors because those can push out a lot more current than the battery itself. Usually you can judge how much a capacitor would hurt if you touched it based on its size. If you have a device with 20 batteries charging a baseball sized capacitor, be very cautious (like the DIY gauss guns/rail guns you see on youtube). Even a thimble sized capacitor will jolt you surprisingly hard. One time I touched the charged capacitor of a disposable camera and the discharge gave me quite the zing.
It can still be dangerous though, it can trickle charge an output capacitance which will deliver the current to hurt you. A small battery only charges it more slowly, the end result is a function only of voltage (assuming the battery has sufficient capacity to completely charge the capacitance).
The suggested board is powered by USB, that's 5V 500mA, so, 2.5W. Let's say the tube is run at the recommended 380V, at 2.5W, that's a current of 6.5mA, which is barely painful, and not dangerous. I guess that with that power, if the circuit really wanted to hurt you, it could boost the voltage in the 50-100V range for a ~30mA shock, which is definitely painful and the start of what is considered dangerous. Electric safety is complicated, there is so much to take into account: current, voltage, frequency, location, presence of water, etc... Skin resistance is far from constant.
Maybe it could do more if it disregards the 500mA USB limit to the full 1.2A that the Flipper Zero can deliver, or with capacitors, but it doesn't seem to have enough of them for a significant power reserve. If it could do that, I would also worry about plugging it to my Flipper Zero or to anything of value out of fear of damaging it, as it would have to be of pretty terrible design, but well, that's AliExpress after all.
For the sexond, Geigers are binary, they only report detection events, not types. So you don't want it to be triggered on non-X rays like interferences from computers around, and you might also want to be able to occasionally remove surface contaminants from the equipment. Both of these are easily achieved by giving it a durable opaque case which is how everybody do these.
And for the first, I believe a modern photodiode taped over is by itself more sensitive than Geigers, even more so if coupled to a scintillator crystal(salts that glows in x-rays), not to speak of spectrometer based systems that can additionally tell energy levels therefore types and biological damage levels of incoming rays.
The real Geiger tube running on display is cool, but that's strictly it. I believe.
Meanwhile, Raysid or Radiacode let you do full on gamma spectrometry, for about 2.5x the price.
And, like, yeah, 2.5x the price. I'm not oblivious to that being significant, but to me it's sorta like an GT1030 with DDR4 - it's about $100 or you could get an RTX 3060 for a bit over $300. Like, you might have a use where you ONLY need a cheap display card, but there's a reason LTT calls the 1030 eWaste from the factory. Similarly, you might get enough out of the Geiger or it might do something the Radiacode doesn't for you but for most hobbyist, I doubt it.
I think the biggest difference here is that GPUs are fairly general-purpose devices. Even if you only need one as a cheapest possible way to output something to your monitor, it's easy to imagine how that might change and why you might as well future-proof your setup.
The other thing you didn't mention about why a 1030 is manufactured e-waste is in large part the competition from the used market. You can get equivalent functionality for a few dozen dollars, so buying a brand new 1030 as an individual makes no sense. This isn't a problem in the specialty radiation device market.
The thing is that most people probably don't buy Geiger counter modules or devices because of a burning need to do some specific tasks, like you would with GPUs. I'll bet that most people buying the Adafruit kit are getting it as a novelty, or for educational purposes, or to just have something reporting the background radiation around them out of curiosity. Because of this, price is the most important factor for these groups.
I've never heard of Radiacode, and looking it up, it seems seriously impressive - especially the portable gamma spectrometry that you mentioned. But I also know that it's a very niche device, and most people who would shell out $250+ for this need it for chemistry projects, exploring irradiated areas, evaluating radioactive items and so on. It's not a lot of people, considering that if you just want something to give you a readout, you'll get the <$99 product, and if you need it occupationally, you'll already have received a professional device.
I had someone tell me a while back $100 is an adult $20. As in, what you saw as a kid as $20 of fun but factoring in how long it took you to get the $20, it's about the same. I know that math will be massively variable, but I like the idea of equating kid brain money to adult money for "toys" like this. A $5 toy vs a $40 toy, as a kid, is a big deal. A $40 toy vs a $70 toy almost isn't, because they're both already "expensive".
I suspect for most on HN, their toy-money equivalence leans to the Radiacode or equivalent being the better buy.
For me, a $100 purchase is something I can probably justify if I think I'll enjoy it a lot. $250 is still a 2.5x upcharge, and I consider these expenditures for a long time, making sure that I really actually need it.
And then, the $100 is just an example reference. It's sold by Adafruit, whose selling point is trading some value in exchange for reliability, convenience and compatibility. When you look at the market in general, I can find countless cheap pre-built Geiger counters at prices that are a lot closer to $50. I can't vouch for their accuracy, but there are so many unique options that I imagine that at least a few will be pretty decent.
I do like my Flipper for how adaptable it is but then end up using it to copy RFID tags as primary purpose.
https://www.aliexpress.com/item/1005004551394154.html this is 32eur
+ ~5eur for an esp32 board and some wires
+ http://docs.espgeiger.com/output/webportal
This gives you a measurement node, with mqtt support, online data export and a web interface.
For ~40eur all together, it's still very cheap.
Like an old glass cup
https://mightyohm.com/files/geiger/images/6275026497_3cf9f17...
Coding a program that could self-heal and survive in such a situation would be fun.
To measure radon (say in a cellar), you'd typically take some dust filter or filter foam, attach it to a fan and circulate the cellar air through the filter, then the radioactive dust collects in the filter, and one can measure higher doses more easily.
> Most short term radon tests will use activated charcoal to absorb the radon gas in the air. Various short terms tests kits will include some type container filled with activated charcoal, usually perforated or screened and has a filter to keep out radon decay products. At the end of testing, the absorber is resealed and returned to the vendor for processing and evaluation.
> When radon undergoes radioactive breakdown, it decays into other radioactive elements called radon daughters (or progeny). Radon daughters are solids, not gases, and stick to surfaces such as dust particles in the air. Dust particles carrying radon daughters can move with air.
[0] https://aranet.com/en/home/products/aranet-radiation-sensor
For Radon detection options are
* direct alpha detection via wet film + process (slow, and day turnover physical processing) OR optical scintillation of filtered air, or
* stochastic gamma detection via a full spectrum and a formula to identify and divide out main peaks and daughter peaks of overlapping common radiometric decay (Uranium, Potassium, Thorium) to guesstimate the radon
Random question for you in the biz: where can I get a muon detector setup? I just can't find them anywhere and would love to gain access to the extraterrestrial and solar weather particle environment.
I love the idea of using the tube and measurements as a random number generator! However, please treat the whole category of homemade devices to measure/detect "bad shit" as novelty and nothing else. If you are actually concerned enough to really measure/detect harmful materials, buy the proper devices. Learn how to calibrate and how to use them properly. The last thing our 911 system needs are people calling with aliexpress radiation detectors going off in a cancer center.
I have a similar Geiger counter that functions standalone and works as an Arduino module. It doesn't appear to be very sensitive because bananas don't increase counts. The only household object able to barely increase counts was some vintage uranium glass tucked away in a corner behind a display case.
https://www.schneier.com/blog/archives/2008/01/locked_fire_b...
Next, I built a simple Geiger counter based upon a Raspberry Pi (Model B) and a Piface LCD display. I wanted to increase dynamic range of the measurements, so I did some circuit modifications to recharge the Geiger tube faster after an event. This allowed for higher counts, but consumes more power and lowers sensitivity. Also, getting the Pi to interrupt on each event for efficient counting has its limitations. A separate digital counter that is reset upon each read sample is better.
Anyway, it's a rabbit hole that ended up taking a lot more time and effort than I expected, but I was happy with the results.
[1]: https://www.bettergeiger.com/
On one hand it's trivial - counts (ticks) per second. However, this (of course!) can be very spiky. I ended up using pretty simple EWMA to smooth the results for user interaction. Anything really works, short decay is fine.
Then the really fun bit, was trying it with more serious radiation source, and guess what.... interrupt per tick, is... really bad! I was easily able to overwhelm the arduino, too many interrupts. Fun project to understand interrupt masking.