"Listening" to radiation with a microphone
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- Опубликовано: 27 авг 2024
- This video demonstrates the use of a condenser microphone to detect alpha particles from a variety of fairly intense sealed alpha sources. I explain why the mic is sensitive to radiation, and compare its (unintended) behavior as a radiation detector to that of purpose-designed radiation detectors that measure ionization. More details follow below:
THE MICROPHONE depicted in this video is the S3-47 sold in kit form by Microphone-Parts.com. It contains a clone of the Neumann K47 condenser capsule biased at about 60 volts and a preamplifier with a JFET impedance converter. Obviously, I have intended uses for the microphone besides just demonstrating this interesting radiation effect. I found the kit to be well-designed and very easily assembled.
OTHER MICROPHONES: I have observed this effect in a couple other (really cheap) condenser and electret microphones; there are also condenser / electret microphones where I don't observe the effect, probably because the grille or the internal capsule design blocks alpha radiation. I am sure this effect works better in principle if the grille is removed but I haven't tried that yet--there is a strong likelihood of electronic noise in designs where the grille forms a Faraday cage around the capsule. The effect will not work at all with dynamic / ribbon / carbon microphones as these work on completely different principles.
OTHER RADIATION SOURCES: Will this work with beta and gamma sources or x-rays? In principle, yes; however, the microphone capsule's geometry strongly favors high-LET radiations (and even for these, is far from optimal). In my attempts to detect beta and gamma sources I have not been successful.
Fantastic demonstration, Carl. I'd love to see an actual audio spectrogram of the sound, as opposed to just a audio power plot. Would it be possible for you to record a short audio file of the strongest source, such as a WAV, MP3, or OGG file, and post it somewhere so that one could download the audio file and perform analyses on it? Thanks again for the wonderful video. Ken - WB0OCV
Hi Ken, a spectrogram is here: drive.google.com/file/d/1z0SttoCoaQ-3p6-RGULYBHU4JOUHbp2T/view?usp=sharing
A WAV file is here (18 MB): drive.google.com/file/d/1fIN-WSUtZVXXAHWFKwOoHw0EAsukjBsV/view?usp=sharing
I should add that the background noise is represented by the blue trace and the alpha detection process by the red trace. It looks like low-frequency shot noise--probably shaped by the ~0.1-second time constant of the capsule capacitance and the FET gate bias resistor. Higher-frequency contributions may reflect the processes of ion / electron drift in the capsule field. The background noise contains heavy contributions from 60 Hz and its harmonics.
So any results ?
Carl Willis really out here doing ASMR now
ASMR alpha particles. I have now truly seen it all!! Fourier transform should contain some info about particle energy...
In principle the FT doesn't have a lot to say about particle energy, more about the physics of the detection mechanism (the ion drift velocity, recombination, depolarization of the mic capsule, etc.). An amplitude spectrum has information about particle energy but it's really incomplete in a geometry like this where only a tiny fraction of the incident particle energy is deposited in the active region of the detector. We can learn a lot about how any detector works--including this one--by scrutinizing the FT and amplitude spectrum and with the fantastic DSP capabilities that digital audio processing confers these days, I think there's a rich opportunity for further experimentation.
Really cool demo, and great explanation. Thanks
A see that Applied Science has a good taste in videos
After bionerd23 stopped posting to her channel, yours is my favourite rad-related yt channel. I just wish you'd release vids more often... Thank you!
ya I really miss her vids. highly informed nuclear science, no bullshit.
@@Muonium1 hope she is ok. Cracking lady
@@glamladwales7056 she is! Though she seems to have lost interest in radiation after getting banned from Ukraine.
@@mandarin1257 she got banned from Ukraine?
@@reginaldpoofta5 according to several people who claim to know her, yes. For breaking the rules of the Chernobyl exclusion zone.
WoW, that is an unespected effect! Great idea, great demo and indeed a great explaination, so its totally a real great video!!
I wish I had more teachers that explain stuff as interesting as you back when I was in highschool 😃 Your channel is very cool, I especially liked the Chernobyl reactor tour.
Awesome thanks for your time & information . You are super scientist
I did not realize that the mic screen was so 'see-thru', my initial thought was there were more layers (i.e. baffling) and the alphas would get blocked. I Googled the S3-47 kit and can see that the screen is more open then I first thought. Good stuff, have enjoyed your previous videos and website. Cheers, Mark
Very nice video! Almost had a sort-of nuclear ASMR quality to it, haha. It would be cool to see you place a sheet of paper in between the source and microphone so that the noise goes down due to the shielding of the alpha particles. Looking forward to more uploads.
I have footage of this exact experiment that I cut from the video. Paper just makes too much sound near the microphone!
@@Carl_Willis Haha, yes I imagine you must have at least tried it! Ah well, great video regardless. I love seeing peculiar ways of detecting radiation like this - reminds me of the days long ago when bionerd uploaded that video of her detecting ionizing radiation with the camera on a smartphone.
@@Carl_Willis You may wish to try Kleenex. It doesn't rustle.
Fantastic as always Carl!
Fascinating presentation thanks xxx
I LOVE your videos, Carl! I'm glad to see that you're making awesome videos again! This was a fantastic one! Thank you very much for sharing this! I hope you have a wonderful day! 👍
Very cool! I hadn't considered a condenser microphone could be used that way!
This is very interesting! I'm looking forward to the series.
Hey Carl. I always love to see a notification about a new video from you.
It actually does make my day. Please keep posting videos. Your content is invaluable. :)
Wonderful video Carl, as always. Great explanations. I look forward to this series.
Weirdest but overall unique and cool ASMR video on RUclips!
Very cool. This is not a demonstration I've seen/heard before.
You should put the mic and an exposed CCD together in a box with your source. It could start a quack medical market for relaxing radiation sounds and visuals.
I'd love to browse the library you have on shelves beside you. They look like some interesting books.
Great video Carl! I'm going to try this experiment tonight.
Absolutely wild man! Who’d a thunk it’d be so easy to perform/demonstrate yet another way to observe radiation! What a cool (and stupidly easy) and unique way to show this stuff! Awesome ☢️!
And here I thought visualizing it in an alcohol vapour chamber was relatively easy... mind you - the visuals are pretty neat though when you can actually see the streams/streaks the ions make however...
Nice demo.
Hey Carl, how active was the Americium source you used? Hundreds of uCi I assume, but would be nice to know the exact number! Awesome video as usual
It sounds like wind! I love it! Very informative, thanks.
Woahhh .. when you did that it blew my mind. Thats kinda exactly what I expected it to sound like lol
Is that a copy of Adam Higginbotham's Midnight in Chernobyl I can see in your bookshelf? Great book. I think I spent most of the time reading it with my mouth in a sort of "o" shape! Love the demonstration and explanation too.
Yes, sure is. I like the book too!
Wondered what the frequency spectrum of the noise looked like - are we listening to lots of events being low pass filtered by the microphone amplifier. Presumably with a fast enough signal path you'd see individual events.
Most of it is very low frequency and is probably rolled off in the circuit. The time constant of the R*C in this circuit is on the order of 1/10 second, so it also has difficulty resetting after events. To get better frequency response a higher voltage bias would be beneficial also, but in a microphone this risks driving the diaphragm into the backplate.
Very interesting, thanks for sharing
Sick!
Could you do an FFT on the output, so we can see the spectrum content? That would be interesting, although I'd imagine it would look like low-frequency "shot" noise.
I have an FFT to share and the link is here: drive.google.com/file/d/1z0SttoCoaQ-3p6-RGULYBHU4JOUHbp2T/view?usp=sharing
I should add that the background noise is represented by the blue trace and the alpha detection process by the red trace. As you suspect, it looks like low-frequency shot noise--probably shaped by the ~0.1-second time constant of the capsule capacitance and the FET gate bias resistor. Higher-frequency contributions may reflect the processes of ion / electron drift in the capsule field. The background noise contains heavy contributions from 60 Hz and its harmonics.
Excellent!
best asmr. Irradiation asmr
That source definitely powerful probably strong 60kev line.
You’re back! Awesome.
Really awesome video! Since your alpha source is constantly spitting out pairs of protons does it build up a static charge? Your 80uCi source is only sending out a current of like 1pA worth of protons, but if you had a super ginormous alpha source on an insulating stand would it charge up like a Van de Graff generator? I think Van de Graff generators usually charge with something like 30uA going up the belt, so you would need like a 2,500Ci source to match that. I assume those are hard to come by :)
Yep, an accelerator beam would make quite an impression on a detector like this! Radioactive sources generally lack the intensity of machine sources.
@@Carl_Willis Thanks! I guess what I'm wondering is what would happen if you put an alpha source in a vacuum chamber on an insulating stand? Would it charge up to a high electric potential?
awesome demo carl
I used to do something similar, but it was visual, not aural, a sort of electronic spinthariscope. Get a cheap webcam and remove the lens, exposing the silicon image detector. Place your alpha source close to the detector and shield the whole assembly from ambient light. When you view the video image, it will be full of sparkling scintillations. Each pinpoint of light represents the impact of a helium nucleus traveling at relativistic velocity. After a while, you will notice that a number of these bright pixels remain, yet after a short time, they go away. Those are alphas that have penetrated into the silicon detector and become trapped within its crystal lattice. Since they have a +2 charge they continue to generate pixels in the video. After a short time, they will capture stray electrons and become neutral helium atoms, which are no longer detectable. I've often wondered if the video signal from this could be used to seed a true random number generator
Ого!
Вот это круто!
Звуковой эффект похож на ветер.
Это и есть ветер из альфа-частиц
That is super cool! I must try it one day but I need WAYYYY more powerfully Am241 source. Do you think 80kBq of Sr90 will work for that?. Keep up the good work!
I think this type of detector is inherently insensitive to beta particles. But, if you built the microphone circuit and attached it to a custom pair of electrodes, I think you could make it work.
very good and calm explained..will this work with beta particles as well?
Beta particles seem to lack enough ionizing power to be successful in this experiment, based on my experience.
Or are the beta particles stronger and penetrating through the material and not being picked up ???................ Erik
Woah, pretty cool.
Cool! But why do you assume that this is due to alpha particles ionizing the air INSIDE the microphone? As you pointed out, an alpha particle wouldn't leave a lot of energy in the 0.05 mm. It's also not very likely that the alpha would make its way inside the hole in the microphone and, finally, it doesn't sound like you are detecting individual particles (no individual clicks) but rather a general noise type deterioration of the microphone's performance. How about this alternative explanation: The alphas are generating ionized pairs all over the place. These are drifting around. Some will make it to the inside of the mic but most will just migrate to the outside of the housing and diaphragm of the microphone, essentially allowing current to flow and you end up with a leaky mic. This actually makes a macroscopic current and it's how a static eliminator works.
The diaphragm in this microphone is at AC ground (and supplied with +60V through a low load resistance, something like 1 Mohm), the backplate's DC potential is at the FET gate bias voltage (a few volts), and the detection mechanism only works when the polarizing voltage is supplied, hence my feeling that the sensitive region must be between the condenser plates in some fashion. Now there is an alternative explanation to the sensitive region being behind the diaphragm: it could be along the front surface of the diaphragm between the metallized zone and the backplate. And I don't have strong evidence one way or the other if this is a viable explanation. The annular insulating area on the front of the diaphragm is relatively small, however.
This is amazing both relaxing and interesting
I'm late to the game, but love it!
Enjoyed this , thanks
thats so cool, looking forward to more videos 👍
I would be interested in a video exploring how various radon levels translate to detectable levels (or not) of beta-emitting daughter products.
Noted. I will do a radon video and hopefully treat your interest. Can't say when, but it's a good topic suggestion.
I wonder what radiation would do to a piezoelectric transducer, guitar pickup or a dynamic microphone?
Amazing!!!!
Somebody put this on the unintentional asmr playlist pls
Radioactive ASMR
Would it be wrong to use the sound to change my mental picture of radiation? This sound is more like a wind of energy, with no perceivable events. Radiation detectors, and maybe the visuals of cloud chambers etc, has made me expect the sound to be clicking, or static with a perceived interval between the events.
You could think of it as rain. A bunch of droplets striking the roof of your house creates a wind like sound. They are individual droplets but there's a lot of them continuously hitting.
When the counter sounds like a fan and radio static.. its hot hot hot! 🤓
Fantastic stuff
Is it possible for this to hurt you?
Спасибо
Great Job
Sounds like death
Can you investigate this further, with a custom circuit that doesn’t have any filtering?
What did you have in mind? All circuits have some filtering, intentional or otherwise. The audio chain in use here resolves from
Would you be able to find out any information about the helicopter canteens that were used in the liquidation after Chernobyl blew up? I found an old video showing the construction of the plant, and then the sarcophagus construction. Apparently there was a helicopter that flew in with a kitchen to feed the soldiers.
Very cool!
Hey Karl very interesting! Can you try it with an iphone?
What ever happened to that block you had from the Chicago pile? You made a video about it 6 years ago.
Good
Mmm alpha decay
What is in the cup source? And how much material is inside of it?
Don't try this if you have high quality condenser microphones (neumann, schoeps, b&k). Use a cheap electrect microphones..
Interesting demonstration! But are you sure that this sound produced by alpha-particles? There is pretty much 59keV gamma-radiation from Am-241 source. And I'm not sure that alpha-particles can pass through gold-coated mylar film membrane.
I have attempted to listen to low-LET radiation sources with the microphone to no avail. Strong x-ray, beta, and gamma ray sources don't produce the sound. I believe that alpha particles can pass through the diaphragm, but they also don't strictly need to in this particular microphone capsule design because they could be ionizing air around the outer perimeter of the metallization outside of the diaphragm. Figuring out how much of the sound is produced this way versus from particles accessing the diaphragm-backplate gap would be interesting.
@@Carl_Willis I think, we need to find mean free path of 5.6 MeV alpha particles in PET and compare it with possible thickness of diaphragm. But anyway if you say, that other types of radiation don't produce the sound it's really very interesting...
@@2ad10man The range of an alpha particle in Mylar is about 40 microns and typical diaphragms are 3-6 micron material with metallization. (The specifics are trade secrets in this business.) I would expect a large fraction of alpha particles to fully penetrate the diaphragm, though by no means all (most of them will be emitted significantly attenuated from the source anyway).
I didnt believe until now that gordon freeman is not fictional
This sounds... deadly
Welcome back.
Hey. What‘s your opinion of the Terra P? Thanks
Put plasma ball near to hear it
He Carl it’s Keaton sorry for not contacting you I had to reset my phone will it work with 1 Uci am241
Hey Keaton! Yes, it will work with those sources (not as dramatically though...you'll have to be REALLY quiet).
@@Carl_Willis ok thanks for responding will have to get message thing loaded up again so we can talk
What about guitar pickups?)
What was the first alpha source you used? Do not really recognize that form factor of alpha source at all.
I am not sure, myself. I just know it is a fairly warm Am-241 source.
This is cool
Aren't you worried to being exposed to the radiation? Or inhaling the alpha particles?
The external dose is minimal and the sources are sealed, so there isn't much of an opportunity to inhale the radioactive material. The alpha particles themselves have difficulty penetrating skin and don't contribute to dose.
If this guy was around during the Manhattan project he would have definitely been one of of the casualties of the "demon core" because you know he could have not resisted the allure of sticking a screwdriver into the damn thing ...lol........... Erik 😮
Любопытно.
Would it work with a vacuum tube?
Dang!
Does radiation effects the magnetic materials of the mic?
We need a new song. Instead of The Sound of Silence, we'll have The Sound of Entropy!
interesting
What is this your hand
But could you detect sound using a radiation sensor?
Yes, as an unintended consequence. This is called "microphonics" and it's typically a serious engineering challenge to reduce in any sensitive electronic circuit. We sometimes trip our reactor due to loud noises in the control room causing unintended signal at the sub-nanoamp level in our electrometers there.
"My name is Walter Hardwell White, I live in 308 Negra Arroyo Lane, Albuquerque New Mexico. 87104"
Bro❤️
Now I want to do this with the WWII German bomber clock I have here at home!
so basically...
The americium sounds angry .
Well sound is actually radiation lol
those are comp[ex waveforms. there is data in those waveforms, just got to slow it down and zoom in. Compare that vs our breath, you'll see a glimpse of the strength of GOD
вот это прикол)
Wow, perfect for seeding crypto lol. True randomness.