Hey there, Ive been looking for a mid grade Geiger counter that can fit in my pocket. I know radiacode is really good, but what do you recommend? I hope to keep it under $300 if possible.
You may thing that proving the inverse square law is easy, but it is not. It is nearly impossible, even in professional settings, actually. It assumes a point source (or at least much smaller than the size of the detector) and no scatter/reflections. Here is what you'll typically get in a simple setup, like the one shown. The activity decreases roughly with 1/r, instead of 1/r^(2) . You can improve this by having a smaller source or one heavily shielded, with only a small aperture aimed at the detector inside a complex shield, but even then it's difficult.
https://www.reddit.com/r/fasciation/s/e3eodpgQXR
Saw this post earlier today and kept wondering about it. Any thoughts?
This is not my garden.
Causes of fasciation:
https://hort.extension.wisc.edu/articles/fascinating-fasciation/
One flower or two maybe ok but an entire field?
Dose rate on a syringe of FDG (F-18). This is about 40 mCi. F-18 has a short half life but super spicy.
New cyclotron engineer here. We are about to run some new lines into hot cells. Typically we have ran Teflon tubes but these are accused of raising the cold mass for 18F. Looking at changing over to a polypropylene tubing. Wondering if anyone can tell me if that is what is used at other facilities, where you get it, how often you replace it? I know it is dependent on exposure but looking for info.
Thanks!
Howdy folks, I'd made this post to showcase the bettergieger s2 mini. Not a lot of content showcasing this pocket rocket. I have to say I am very impressed by the sensitivity (I can detect this SPICY WW2 compass from a yard away). Unlike my GQ-800, it can also detect radium clock dials as well. Well worth the money, some see the USB-C as a con, I see it as a pro. 10/10
Yes I am aware of the radon this produces and exposed radium dots. It is handled with extreme care and stored safely in an airtight lead lined ammo can. cheers!
Hey yall, I work at a thrift store (as said) and we got some radium clocks in today and I’m probably overly anxious about them but I figured I’d ask anyway. Am I good for putting these out? Idk if one of the three actually *is* radium, but the other two absolutely are. Not sure if one cracked in the bin too which has me nervous. They’re currently sealed in bags in containers separated in a well ventilated area.
I’m gonna attach pics of the clocks too, anything else for now or the future that you guys think might be helpful I would really appreciate! Thanks!! (Last pic is of what I think might be some of the paint that idk, maybe chipped off? Nothing else in the bin is glowing like that) if I can’t sell them, let me know if you guys think a museum would like them or something similar!
Just got to the ground after a pretty short flight. I took some readings from taxiing all the way to cruising altitude and partially into the descent.
My maximum reading ended up behind ~145 CPM at our relatively low cruising altitude of ~22,500 ft above sea level.
For those worried about it, I muted everything and turned down my brightness. I also tried to keep it angled away from the guy next to me to avoid worrying anyone.
my dumbass drilled open a smoke detector small hole to test a cheap counter I'm goid right?
As a lot of you know, the DP-63-A has an extremely radioactive radium dial (or at least some of them do). Like all radium paint, the radium degrades the zinc phosphors over many years and the paint can no longer glow without the use of a UV light source.
Ignoring the obvious contamination problem with these units, let's say someone got a hold of one of these and decided to paint over the radium dial with a new layer of zinc-sulfide paint. Would the unit be able to glow by itself again? Also, would modern non-toxic europium-based paints work with radium as well? I feel like this would work, especially given the insane amount of radium found in these. But I could be wrong
Hey folks,
I’ve been playing around with my gamma spec setup (amateur, low-fi) and wanted to share a result that taught me something new.
Background: Here in southern Bavaria, some areas still have detectable Cs-137 from Chernobyl in forest soils, wild boar, etc. I’ve personally measured it in my garden soil. So when a neighboring farmer gave me a sample of fresh raw milk, I thought – why not see if any shows up in the milk?
The result:
It’s not distinct peaks – it’s a broad continuum. Classic Bremsstrahlung shape. (And yes, I love that English just borrowed that German word - Arnold Sommerfeld, 1909)
My interpretation:
I’m indirectly seeing beta emitters in the milk. Fast electrons from beta decay get deflected by the aluminum housing of my detector (or other surrounding materials) and produce that continuous X-ray spectrum. If I had a proper HPGe, I might resolve some characteristic peaks within that continuum, but with my amateur setup, it’s just a noisy, weak excess.
The big question – which beta emitter?
Most likely candidate: K-40. It’s naturally abundant in milk (potassium). The gamma line at 1460 keV (10.72% branching ratio) wasn’t elevated above background, but that’s not surprising – the beta emissions are the dominant decay mode. So what I’m probably seeing is Bremsstrahlung from K-40 betas. Or you have any other explanation?
Takeaway for other amateurs:
Don’t just stare at the photopeaks. That low-energy continuum can tell you a story too. It’s pretty wild that we can indirectly “see” beta emissions in a gamma spectrum, even with a humble setup.
Anyone else seen similar effects in food samples? Could anything else (natural Po-210? fallout Sr-90?) contribute to beta activity in fresh milk around here, or is K-40 the only realistic culprit?
Cheers from Bavaria ☢️🥛
I covered both my am 241 sources in resin just the centre [sorry for the bad photos] but i used a brush. It was a paint brush one of the fine haired ones but i just brushed and uv cured the resin. Was this dumb and should i dispose of the sources? I used sticky tack to hold them for the photo so dont expect it to look nice
Would someone with a suitable detector measure a banana and then a pack of cigarettes?
Watch Veritasium's short called "The Most Radioactive Place On Earth" ... Their assertion is a smoker receives a higher dosage than someone on the ISS due to radioactive material contained in the tobacco. This caused my BS sensor to tingle, now I trust Veritasium but everyone gets a chance to display an oops every so often. I'm wondering if someone missed a decimal point somewhere along the way.
Now maybe a banana is too low of a rate to see due to background radiation, but if their assertion is correct then the pack of cigarettes should be well above.
Is my BS sensor mis-calibrated, it could be ... having a sense of the relative radiation levels is difficult.
This is the last part of this lengthy, but fun experiment.
Part II was posted here: https://www.reddit.com/r/Radiation/comments/1sn7dqh/ambient_rn222_adsorbed_on_activated_charcoal_part/
In short, I kept the sample from part II and remeasured it after 7 and 13 days respectively. The idea was that when Rn-222 decays, the sample activity and x-ray fluorescence will decrease, allowing to see the elusive Pb-210 peak at 46.5 keV better. This time I used the Radiacode 103 (for the main experiment the 103G was used) because its lower energy response is better suited for this.
I thing I got it.
Well, after a few weeks of circuit design and tedious programming, my home-built Geiger counter is (for the most part) complete!
My detector is able to detect all three types of radiation (alpha, beta, and gamma) by utilizing an LND7311 pancake GM tube with a thin mica window, run scalers, watch for peaks in radiation values, and even send data to a computer through the USB port.
The hardware for it is simple and straightforward: it’s essentially just a 555-timer-powered boost converter that’s switching an inductor with an IRFBG20 MOSFET. For the inductor, I’m using the secondary coil of a CCFL transformer that I salvaged from an old computer. This allows for very low current operation (inductor only draws a few mA) but very high voltage production. For my counter, I set the HV to about 860V and double checked that it was clean on my oscilloscope. And thankfully… it was beautifully stable.
The tube’s anode is connected to +860V through a 10MΩ resistor (yes, I’m aware, 3.3MΩ is preferred), while the cathode is tied to GND through a 10KΩ resistor. That node is also attached to a transistor base, and the collector of that goes through a one-shot circuit with another 555 timer to stretch that pulse. And the output of that is a clean, variable-duration pulse that can be connected to anything capable of processing signals. Could be as simple as a buzzer or led, or as complex as a full-blown microcontroller.
I chose the microcontroller. That would let me display and log radiation rates digitally, which sounded pretty cool. So, I fetched my Arduino Uno, connected a speaker and OLED display, and wrote 600 lines of code that was capable of measuring count rates, being a scaler, reading peak values, sending radiation data to a computer, and changing all settings using some buttons and a rotary encoder.
Unfortunately… my program took up a lot of storage though, and caused glitches on the OLED screen. So I was forced to switch to using a bigger microcontroller, and thankfully, I happened to also have an Arduino Mega. The Mega is a giant controller with many more pins and higher power draw and storage than the uno. The storage is what I’m here for though… the extra pins are excessive and the higher power draw is… wasteful. Using the Mega bumps the wattage of the setup from 450mW to 900mW. But… what other choice did I have.
Anyways. All I had to do was transfer each wire to the bigger controller, and upload my code again. And now it works perfectly! It has lots of user-changeable settings, operation modes, and features, but there are still many more to add. Attached is a video of how it is so far though.
Hi! I'm recently becoming more and more interested in the history of the use of radium in everyday products during the Cold War era, and I recently saw a video of a radium ore water revigator in which the creator tested the radiation using a Geiger counter. The reading was about 20,000+ CPM, and I was wondering if objects like this from the radium era are dangerous to have in your home if you are not ingesting or inhaling anything that has made direct contact with the object of course. I was under the impression that anything over 10,000 CPM is considered a health risk, but after doing a little bit of research I read that it's different if the radiation is coming from an object versus it being in the air. Can anybody expand on this claim? I'm struggling to find further information online but would like to learn more about levels of radiation on these types of items.
I have recently purchased a radium clock, which likely has trace external contamination, and was wondering if it’s safe to display in a cabinet. Would placing a mat underneath it prevent the glass surface of the cabinet from getting potentially contaminated by radium dust? Thanks!
I got the whole box for like 8€ from an old man