an affordable alpha spectrometer. ☢️
ฝัง
- เผยแพร่เมื่อ 15 มิ.ย. 2024
- I wanted to find out if the PIN diode detector of the KC761 was capable of actually doing credible alpha particle spectroscopy...
I am just starting out on my voyage of discovery on this subject. I have worked on this project for about 3 months and this is the result.
I am guessing that the number of TH-cam watch hours that this video generates will be lower than that actual time I have invested in this myself, it is after all, a fairly specialist subject. That's said, the payback is in the knowledge gained...
The Links
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NIST physical measurement lab and ASTAR stopping power calculator:
physics.nist.gov/PhysRefData/...
Stoppi video:
• Homemade alpha-spectro...
Link to the KC761 manufacturers website:
deepace.net/product/measall-r...
Chapters
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00:00 Introduction
03:00 Some Info. Some background information in gamma and alpha spectroscopy.
06:07 Hacking it. Upgrading the product to allow alpha detection.
09:19 Experiment 1
10:07 Experiment 2
12:38 WTF is this? Understanding the measurement.
17:24 Experiment 3
19:53 Experiment 4
21:54 Summary
23:34 What Next. Perhaps I will take this further...
24:16 Bonus Level. The PLA type-7 Geiger counter - วิทยาศาสตร์และเทคโนโลยี
I will be doing a video on the beta spectroscopy function as well, but it will be a much shorter video, this one is so long, almost killed me!
Hello! I am trying to read beta signals from uraninite with my shiny new KC761B but I only get one peak at 200 kev and that makes no sense... Initially it gave out signals without any source, that stopped after updeting the firmware and rebooting a couple of times... To be expected, somehow, all things considered.
Do you have any idea how that can be?
@@PeterMarchl I'm seeing similar things, I'll get back to you when I figure this out.
@@project-326 does your hacked old model has the same problem? I wondered if it's all xrays...
@@PeterMarchl The behavior of my old 761(A) is a little different on the PIN diode. On the 761B, even after upgrading to the new firmware, I still get a few counts, even when there is no source. I suspect that they reduced the threshold for noise discrimination on the PIN diode MCA.
I have a bunch of questions for the company but I will need to wait until after Chinese New Year to send these questions to them.
I have found a few things that I want to ask the company about, regarding the 761B and this is why I haven't released the video about the new model. They are normally pretty helpful with questions, but better for me to wait until after CNY and be sure to be asking the right questions...
@@project-326 ok, I wondered why I got no answer from them, it's new year...
The kechuang forum mentioned that the threshold has been changed, its another hardware setup. Also I have found out that the false readings can be stopped by repeatedly rebooting the device but still afterbsone time it restarts. Some voltage bleeding or buoldup? I hope it's a firmware bug and not a hardware or soldering problem. I'm not enough of an electronics expert... I have to constantly remind myself that this is not a typical consumer product but an ongoing experiment and rooted in another philosophy so to speak. What a ride...
You SOOO crack me up when speaking about that German POS! Love it, and... how much evidence of that fact do people need? Keep up the excellent work. I'm learning a ton!
After an exhaustive search, I have found something worse, something FAR worse...
I have a couple of videos that I am busy with, but after that, I going to have a crack at the true gigashite of detectors. Stay tuned!
:-)
Excellent again. This channel is addicting!
The forum bit was spot on lmao
What!? Arsehats in an online forum??? Surely this is a one-off.
Love the vids!
There are inexpensive sliding covers for laptop cameras that should work well to cover the detector port. Odd that the manufacturer didn't build in a sliding door.
I agree, this should have been solved mechanically...
Great vid. The one that teach you things are the best.
Really enjoyed this. The title cards, music, and transitions make it relaxing to watch.
The variation of energy from distance and blocking layers makes this more interesting because you have to work to understand the whole measurement system to determine what the original energy is. Might have to get one of those meters..
The chapter titles is the bit of the post processing that I have fun with. It is usually where I experiment with new visual effects I am learning. Its a hobby channel, so I'm gonna play...
excellent video again sir! Neat little device ! I am considering buying one thanks to your review.. I have made some decent vacuum chambers with PVC pipe for rough vacuum applications on the cheap. Epoxy glue work great for small leaks. Unfortunately, alpha spectroscopy demands tedious sample preparation to be valid, but you can still have fun ! You know you don`t have the full energy until your peak is a vertical drop to baseline on the right side (max energy) .. Great work!
Thanks for the input, I have been trying to figure out what pressure I need inside the "vacuum bucket", some comments have indicated that the pressure should not be too low, or back-scatter will become problematic...
Do you have any advise on what pressure I should be aiming for?
depending on the size of your chamber I would assume the mean free path range of the alpha would be no more than a few cm so 10-3 Torr )0.1Pa) range sounds about right@@project-326
Love how thoroughly you tracked down all the variables.
Vacuum bucket with Plexiglas top used for impregnating mineral samples with resin should work well for that pin diode experiment. Added advantage, way to stabilizing your ore samples so they don't shed radioactive dust into your environment.
Really like the deadpan voice...don't change it.
The chamber does need to be dark, so black acrylic sheet for me...
Excellent video! Saved me a LOT of fooling around to learn about alpha particles. I was not clear as to how the spectrometer reacted to distance. Note that vacuum is just as complicated as particle physics! The density of particles in a vacuum varies exponentially with pressure to a certain point, then gets almost irrelevant. You will need to get to molecular flow pressures before the gas molecules are not going to affect you alpha particles. Unfortunately, this will take more than a simple mechanical pump. Get ready to spend $$$!
for alpha spectroscopy, an imperfect vacuum is preferred, it removes most of the back-scatter from the measurement.
@@project-326 If the alpha hits a gas molecule doesn't it change the speed, thus the energy reading? Where is the back scatter coming from? I would wildly guess from gas molecules? Seems like that site you went to for information is run as a cult. If you are not "in" they treat you like crap.
@@glasslinger Neptunium has some great insights into the issue and why an imperfect vacuum is better for accurate measurements. You can take measurements at more than one distance to allow initial energy to be calculated. I suspect that the back-scatter is coming from the vacuum chamber walls, at very high vacuum, there is negligible energy loss, so they alphas are going to end up at the chamber walls...
Had a wonderful time watching and got a few good laughs. The detailed work was impressive.
Really really good viedeo! Thanks !
My Americium-241 sample shoots out so much gamma from decay chain reactions my RadiaCode103 goes crazy. That and Thorium2%/Tungsten welding rods. Great video!
i have a GMC500+ that i modded with a LND712 tube and it gives me around 60,000cpm on an AM241 source and when i put it back in the metal can it drops to almost nothing my thorium lantern mantles make it scream too while my U ore only gives off 3 to 5k cpm hehe
ABY Radiological Observation and Analysis Dosimeter... Sounds vaguely familiar. 🤔
I forget who said it, if you can't explain a subject that you're supposed to understand to a child then you don't actually understand the subject at all
IIRC that was Einstein.
Forums seems to be useless. I was banned on physics forum for showing people there did not understood Newton's 3'rd law. It makes sense that energy of alpha particles is their kinetic energy as it is a massive particle the nucleus of an atom so way, way heavier than electrons.
I have a Radiacode 102 is a gamma spectrometer barely getting in to beta and just got it out to check the limits but it was again dead (overdischarged battery). I think I charged it two wheels ago when I also found it dead. So it may have significant self discharge while powered OFF witch is bad as that means the battery will eventually die.
I also have a Radiascan 701A but that can not measure energy is just a counter that should be able to detect alpha particles. I'm not passionate about this but I like to have this meters just in case I ever need them.
The amount of snobbery and exclusivity in modern day acedmia is quite disheartening.
A cheap solution for the vacuum chamber can be a simple mason jar and a vacuum pump (hand pump or a real pump)
Love the videos. Keep it up
Also, now I want to get an old Chinese geiger counter for a strontium source for my collection
Implosion city next stop.
@@donaldhoot7741 I bet you never made a vacuum chamber
Warranty void stickers violate the Magnuson-Moss Warranty Act of 1975 in the US. They have already been rule illegal by the FTC.
Wonderful. I turned from being a grad student in hi energy physics to computer science some time ago (the 70's...) I actually remember some of this stuff! I recently got a Radiacode 103, which is a wonderful, versatile device. I would hope that Radiacode has viewed this presentation, and is contemplating adding a PIN diode detector for the, let's say, 105 version... Looking forward for your review of the revised unit!
I know what you mean, but at the same time, I like the RC102/103 just as it is, I kind of think of them as one for the road and one for the home-lab...
SO BEAUTIFUL video!!! I could not understand everything, partly because of the language, but my interest is great and I will try to clarify everything that is still unclear to me 🤓
Very Good!
Thanks!
Alpha detection isn't that hard. Spectroscopy (as you have found out) is a major undertaking. The industrial/commercial grad equipment we use at work uses a bare scintillation crystal in a dark vacuum chamber. The documentation says it doesn't pull a 100% perfect vacuum as the slightest amount of air helps reduce back scatter. Don't ask me how this helps as it is above my pay grade.
Nice insight, I will remember that about the vacuum not needing to be 'too good'. What kind of vacuum level is good?
The manual says between 0.1 and 2.6 kPa for recoil suppression.
@@connclark2154 Ah, to suppress recoil of the parent nucleus.
That is really useful thanks!
I was looking forward for this video, interesting way to optimize the sensitivity of the PIN Diode, probably you ruined the sealing by cutting the foam rubber, easily fixable. I am waiting for the new Measall to be released, cause currently at a whopping 12% FWHM value for Cs137, its gamma spectrometer is quite useless. The new Radiacode 103 which I just purchased has a FWHM for Cs137 of 8.4% (Anything above 8% for a nuclear phisicyst is useless and they throw away many NaItl crystals due to that, but for hobbyists around 8% can already show something.)
Anyway, I think that the best option to use this feature on the Measall with scientific value is to calibrate it on a known source (uncovered not like stoppi did with the am241 that was in an alloy so had much of self absorption and shielding by the gold film) so that way you can already compensate for the energy loss of mylar, aluminum deposition and air between, which will be the same for all mesurements. Obviusly to maximise the properties of the sensor it should be used in a vacuum chamber, but for that I would suggest replicating the stoppi circuit, maybe with a bigger PIN diode (Its BPX61 is quite small at 7.5mm^2) like for example the s2386 8k by hamamatsu at a decent 34mm^2 (I am doing it myself).
If you modify the measall you loose maybe its best property, being a somewhat decent portable multi radiation spectrometer.
I'm going to reply to your very excellent comments a bit later, I'm on a business trip, so will get to this once I get some quiet time...
Can't stop laughing :) Wonderful!
This was a very good and informative video! Thank you very much! I have by now beta measured only a stronk thorium lens and autunite. I have very much hesitated to hack the device but your idea of screwing g on a 3d printed cover seems very useful. I am pissed about the firmware and software limitations but the actual hardware is really good and well thought out. It grows on you, tis little bugger!
I always tell folks, buy the RC102/3 if you are new to the subject, only buy this is you want to learn more...
Lets keep in touch on tis lil' bugger, it has its own advantages, but they are hidden from the average casual user.
@@project-326 I will! I have some interesting reading from a very small tritium tube which the 103 doesn't detect at all but re diode does. So I think it is a very good complement to the 103 in fact! I'd send the bmp but that isn't possible I see...
@@project-326 I just wonder... What if someone with an opened diode, due to heavy tinkering wound print a cover with a slit so there's strange physical effects takin' place, doing gaussian things to the light coming in... What would the Kc show?
16:55
Not a bad idea to calibrate the pin diode for alpha samples at a certain distance from the detector. Using a well known standard from Am241, that would be a great calibration source.
Unknown samples should then be close to the true energy of the alphas being emitted.
It is an interesting idea...
But I am keen to keep the calibration based upon the absolute measured energy, let me explain. A few months ago, I make a random purchase of an strange Am-241 button on XianYu (the Chinese equivalent of Ebay) and although the gamma activity level is is about 3.5x that of a standard button, so indicating that the activity level is probably about as advertised (approx 30 uCi), the energy curve is very strange. This tells me that the material covering the Am-241 is not just the standard gold foil that these sources normally have.
I have actually been doing a bit of an investigation into this source construction, I am wondering (hoping) if this strange little source was from an application that needed some neutrons and that this foil is actually beryllium. Knowing the absolute energy level gives me some information to work with.
Sorry for the long and rather boring reply!
:-)
@project-326
This is a great response! It's very interesting to hear your perspectives and look at your research into this technology.
I'm kind of in the market to pick up a handheld gamma-spectroscopy system, so these videos are great to make an informed decision.
@@justinb2630 I will be reviewing the Radiacode 103G fairly soon, keep an eye out for that video...
@project-326
That's great, because I saw a claim that the 103G was a germanium detector (I can't remember where I saw this claim, but I think it was in another TH-cam video).
I commented on that, challenging the claim, because I usually work with High Purity Ge detectors, which need to be cooled to -185 C. I got no response, so I'll be curious to see what you uncover. 😁👍
@@justinb2630 Woah, HPGe is pretty serious stuff. The RC103G is using GAGG.
IIRC one problem with silicon detectors for alpha detection is the cumulative damage the alpha particles cause to the silicon. I suppose this won't be a problem as the device is built, but doing lots of alpha detection with the bare PIN diode will eventually degrade the detector.
I heard that this can be a serious issue for research labs that work in this field, I guess that their detectors will be getting used extensively.
Just the 5mm of air is bringing the energy down a lot, but I am planning to create a vacuum chamber front end for this device, so that might become problematic.. Fortunately, the detectors are pretty cheap and although my use case will be with a VERY low duty cycle, I will take your advice and ensure that the replacement process is as simple as possible...
Wow! I had no idea that alpha spectroscopy was a thing! Very cool!
I have a GQ GMC-600 Plus Counter Detector Dosimeter Alpha Beta Gamma X-ray. It claims it can measure alpha but I've never been able to convince myself that it could detect alpha particles. Is there any hope of doing alpha spectroscopy with such a device?
Unfortunately, a Geiger counter can just count the events and cannot measure the energy of each particle it encounters. Your device should be able to detect alpha, just remember that they are very short range in air, not much over an inch before all of the kinetic energy is lost.
Although the subject matter is far outside of my area of training, I found the video very interesting and a source of learning opportunities. Thank you.
When air is let back into the vacuum chamber that you said you might use, could the resulting air turbulence blow contaminants around inside the chamber and onto the alpha sensor, thus ruining it? How to prevent that contamination? How to determine if it occurred? Just rhetorical questions.
Looking forward to more videos.
That is a good question, I will look into adding an air filter. I'm not too worried by surface contamination like general dust, the photodiode die has a surface passivization of silicon dioxide (quartz), but I would worry that microscopic hard materials could smash into the diode surface at high velocities and cause damage to the passivization layer.
@@project-326
I was thinking also of radioactive particles being blown around and sticking to the sensor surface.
If the tubing that lets air back into the vacuum chamber included an orifice of sufficiently small diameter, that would limit the velocity of the air and therefore the turbulence, but you would not want the orifice to be in the tubing that draws the vacuum because drawing the vacuum would take forever.
Thanks for the insights, I always take note of people that take the time to comment on my little channel and know from experience that everyone has something to add of value. Learning is a lifetime-long process, sadly lifetimes are limited but learning is not. I will definitely take your idea on board, others have also discussed similar concepts, but not as specific as you on this topic. I will keep you updated as I progress...
My father was a very uneducated man, but that didn't mean he wasn't smart. In his short life he managed to bestow a great number of gems of advice onto me, the one that I always use when replying to YT comments is this....
Always listen to advice, you can always choose later, to act on it or not act on it, but always listen carefully, EVERYONE has seen at least one useful thing that you have not, and usually a lot more than one thing!
🙂
And the other thing he said about advice is this (wow, you have really triggered my childhood memories, thank you for that)...
"Pretend you are stupid when being given advice, and pretend you are smart when acting on it."
This is apparently exactly what I was looking for!
Even though it's probably the cheapest that's not total shit, I'm going to have to keep trolln eBay until I find one 3rd price... or less.
I tried searching elsewhere but autocorrect keeps changing radiation to radiator and I can't seem to fix it.
if you get enough alpha radiators, you will have a whole central heating system off ebay...
@@project-326 RTG baby!
Speaking of,
Who still sells those BS negative energy ionic healing pendants?
Like is that how the Chinese get rid of their nuclear waste, by selling it to low IQ American crystal loving hippies?
Calibration is fine, it’s the same thing as you do for gamma spectroscopy. If you put unknown source at the same distance, you could measure the energy. Unfortunately, it does not take into account gold layer.
yes, so that is my issue with the Stoppi video. Mind you, whenever I see perfect results from science done in a biscuit tin, I'm always suspicious.
Dear Studio326, do you know if there is an affordable alpha spectrometer for detecting 218Po that have an energy level about 6 MeV? Thank you very much. Regards
I have not heard of any and certainly nothing that was more affordable than the KC761 series.
@@project-326 Thank you very much for your answer but, I have a doubt yet. In front of spectrometer it seem that the meter can only measure up to 3 MeV, it's that true? What is the way for to measure up to 10 MeV? Thank you. Regards 🌞
@@octaviolazaromancilla2732 Well, alpha spectroscopy is quite complex. For a start, you are just never going to be able to measure the actual theoretical energy level of an alpha particle unless the sample and the detector are in a vacuum. Secondly the published energy loss doesn't account for the recoil losses, just the overall energy lost to the decay process. If you were to measure 6MeV (theoretical) alpha particles at 30mm, then they will have lost all of their energy traveling though that much air and so nothing is left to detect. With direct contact with the sensor area of the enclosure, there is 5mm of air to cross, so the alphas will have already lost about 1MeV by the time they reach the detector. If your source has a couple of microns of gold foil for protection, then you lose another MeV. I think that the instrument is good for about 5MeV but there is just nothing that can produce 5MeV at the detector after the losses from the air, the Mylar film and any losses from protective coverings of the source. Ignoring cosmic rays, I don't know of any isotope decays that can exceed a kinetic energy of 7MeV that would require this detector to even need a range that can exceed 5MeV. If you know of any >7MeV alpha decays, please do let me know, I'm always keen to see new things...
AAAAHHHH you got Sr90!!!! Fascinating video. I have a Radiacode 103 and it goes nuts near the same exact Am source as in this video. Super curious about alpha particles....
Thanks for watching that mammoth video to the end. I really makes it all worthwhile when like minded folk bother to do so. This source is mindbogglingly active, at least 2 mSv/h!
yeahhhhhhhhhhh, I gots some Sr90, finally....
can you measure Radon directly or by filtering only?
I am very skeptical of the videos that I have seen that show concentration of radon gas using filter paper (or alike) over the nozzle of a vacuum cleaner. Normally a survey is done over a long duration and using a gamma spectrometer. Radon is a noble gas, it is chemically inert. I can't see any mechanism for it to want to 'stick' to the filter any more than the oxygen or nitrogen in the air would.
Radon-222 is not easily directly detected but looking at the measured proportions of the various gamma lines in the Uranium decay chain, the levels can be estimated, but it takes time to collect enough data and some background knowledge (or a willingness to learn) to be able to process the data.
@@project-326 the other issue in these measurements is they never refer to the time of filtration as if the volume of filtration is not counted it could only be counted the presence of Radon but not the amount. Is there any changes in window that you noticed in KC761B, as it still does have the cover. The second do you think that settings the window for background discrimination in specific isotope detection that could make the CsI(Tl) effective for alfa measurements, rather then use of semiconductor or Ag(S) thin detectors, so radiacode could also be fine for alfa detection? By the way it would be worth the mention that radiacode is the only makeing automatic isotope identification, others make it only by manual set to the peak. But my question to the manufacturer is what if there is a mixture of istotopes like in most contamination, i.e. Cs-137 and I-131 is it the others detected or the peak only?
I think removing the sticker will lose the waterproofing - that will be why there is a warning about it. Strange nonetheless.
If it has mass shirley.
:-)
when strontium 19 video will be out ?
Subscribe for his Videos and you will get an instant notification ;)
Soon my friend, soon.
What’s about this diy ? Is it total trash than or could this have worked if correctly calibrated?
alpha spectroscopy is not a straightforward subject and it certainly isn't plug-n-play in the same way as gamma spectroscopy can appear to be. Measurements of kinetic energy depend highly on the various media in play and the original decay energy of the alpha particle. Calibration is something that needs to be done alongside each measurement based upon a lot of factors, it's not something that can be per-calibrated unless the instrument is only used for a single type of experiment under the same conditions.
KC761 alpha spectrometer is better than Stoppi Alpha spectrometer?
No idea which is better. In this case, better, probably means lower noise. My problem with that video is how the calibration was done, it was a little misleading.
@@project-326 OK , can you explain comparison between KC761 Alpha spectrometer and Stoppi Alpha spectrometer
@@pak7524 the principle of operation is identical, a reverse biased PIN photo-diode with the glass cover removed in a dark enclosure. The Stoppi video is using the freeware Thermino MCA software to perform the actual spectroscopy and the KC761 has a dedicated, pre-calibrated one. The Thermino MCA software doesn't have any idea what it will be connected to so the user needs to figure out how to calibrate it.
It's a pin diode with the lid cut off a real b astard of a job as I found out once, still have the scars.
I'm about to do the same, trying to make a vacuum chamber for one...
我们即将出品一款能量分辨率为6%及3%左右的便携式伽马能谱仪
please contact me on morganstudio326@gmail.com with a WeChat ID and we can discuss further...
我有兴趣了解你的产品，你可以发邮件给我。。。
This video will cost me over 300€....
Do not buy it!
I bought it month a go and I"m really disappointed...
And this will cost you 400$ or more because of customs and shipping
@@gentlemanhk please explain. I also wanted to buy one...
@@gentlemanhk What was the disappointment? Apart from the f*** tax, shipping, and customs shit? I want to find ore quicker and be able to tell the difference between thorium and uranium ore.
@matssoderhall1780 if that's all you want to do I recommend the radiacode 102 because it's basically the same thing just smaller and draws less attention to you
Also you can map out radiation on Google maps so you can find hot spots while walking
It's about 300 bucks after tax and shipping and it's not like you will need to do alpha spectroscopy on uranium ore out in the wild
@@The-One-and-Only100 I am using a radiacode 102 already but i like the idea to have a even more sensitive device. Also the radiacode 102 can not give a clear answer to what is in the ore i find as Uranium and Thorium decay chains have daughters with similar energies.
Awesome video, although my eyes glazed over @ 4min and I had to stop watching. thumbs up so who cares, lol.
Oh well, shame really , the naked dancing girls don't start until 5 mins into the video...
@@project-326 Now you're talking!
You can only do alpha spectrometry in a vacuum!! And the energy of an alpha particle is because of its mass not of it's velocity!
If that were the case then all alpha particles would have identical energy levels...
Mass × velocity squared. Not just mass.
Stop beeping the words
But I am an AI and if I insult the YT algo AI, then it will delete me!
But if I am talking about the fucking Gamma Scout, well there are no bleeps there...
Really I don't like robot voice please use real voice
It is his real voice so don't judge someone by their voice judge them by the quality of the content like this is literally worth more than uranium ore
I like the AI voice. He apparently puts a good amount into tweaking it to say things just right. The humor comes across well in it IMO.
@gblargg Shush, don't let them know about our ai overlords
When I recorded my previous video (kids in the Uranium mine), I did just as you suggest for an experiment, ie record using my own voice. Given that our kids were in that video (albeit with faces pixelated out), I had to seek approval from Mrs 326 before uploading it. After hearing my natural voice on the video, she forbade it and I had to completely re-do the video again (which took ages). It made me feel even worse when she tried to placate me with the not so soothing words "My Dear, I have come to love your silly voice, but I would rather your subscribers didn't know that I married a man that has the vocal range of a pig being slaughtered"
@@project-326 damn 😳 I never knew that was a sound that could be replicated