Some time ago I first saw one of your videos. You used an ugly soldering iron and crude hand tools. I immediately thought something like "This guy is so amateurish." The more DiodesGoneWild videos I watched the more I realized how wrong that first impression was. Your straightforward style and the way you explain circuits in plain language is wonderful. You bring the subject of electronics down to earth, not hiding it behind complicated language or fancy equipment few can afford. Rather, using found and fabricated tools you say to your audience "You do not need a 200 dollar power supply, an 800 dollar oscilloscope, and a lab full of specialized tools to start learning and playing with electronics." Too many channels seem to say just the opposite. I am glad that you discuss safety while still doing things "the book" calls unsafe. We all do these things in real life but worry that people unfamiliar with how to stay alive will jump in unaware. Your cautions are well placed and helpful I'm sure. I have been surprised how much I have learned from your videos. Today as I watched your description of your understanding of the magnetron operation for just a moment a light went on in my mind. I suddenly had a glimpse of understanding of the "How." I have read about the function of magnetrons and their fascinating history (A Secret Weapon, highly classified!). Still when it came to How it actually resonated always stayed in my mind as "...and then Magic happens." Today I think I understand and will go back to the books. That alone is worth boosting my Patreon support. I encourage others to give as they can to support DGW's continued efforts.
I couldn't agree more! I also found the equipment used a little dodgy at first, and thought he barely knew what he was doing, but know i feel quite the opposite now, no doubt he knows what he's doing and he is impressively good at communicating it. But as they say: "If you can't explain it simply, you don't understand it" Thanks to DGW for the fantastic videos :)
A friend of mine whilst preparing to open a RADAR museum was given permission to look through the GEC research laboratories in Wembley after they closed the site. He discovered all the Magnetron prototype blueprints, correspondence marked top secret, production drawings etc...The whole history of the Magnetron from the late 30s through to the late 40s boxes full. In the event the museum idea fell through , yet nobody seemed interested in the complete history of the invention that arguably saved the world. The Imperial War museum didn't want them etc..They are still sitting in cardboard boxes. I have some scans. They also made and developed some great audio gear (like KT88 ) along with dozens of other amazing things etc. Great video as usual. Love your channel.
Dear Martin D A, As a physicist and researcher working on microwave plasmas, your story catches my attention. Such files would be invaluable for the history of science but also for teaching at the university (particularly for electrical engineers, physicists). I assume that such files aren‘t classified any longer (besides that commercial magnetrons are obviously under patents protection and actually so cheap to produce that no one would spend time to design one nowadays). Making such historical files, in a way or another, available would save prior knowledge to posterity and shine light on the (to my knowledge) not so well described physical principles that led to their design. Is there any way to access these files and to see if they could be made open to the scientific community? Thanks in advance for your reply! Kind regards, Emile Carbone
This is hands down the most informative electronics channel in the whole internet. I follow every electronic channel in RUclips (some are so small they might have 50 or so subscribers) i watch hundreds of videos about electronics and I'm not exaggerating when I say it. Thank you very much sir.
Beryllium oxide was very common a long time ago, but most modern magnetrons do not use it anymore, but use aluminum oxide instead. From what I have been told- again, I can't say that this is fact- a pink insulator indicates that it's a newer aluminum oxide insulator. A white insulator could be anything, and should be assumed to be beryllium, especially on a newer unit, because the pink color- as I've heard- indicates that it's aluminium oxide, with chromium oxide added. Once again, this is information I've learned from a third party, I can't vouch for its accuracy. What is certain is beryllium oxide WAS used in older magnetrons, and may still occasionally be used today, though most have switched to aluminum oxide.
Pink color makes sense when sapphire is made of aluminum oxide hence the pink color on cmm probe tips. I wonder if that's its spectroscopy color too? How they detect elements on planets/stars
In some old russian owens, "military grade" magnetron design used, and yes, that magnetrons contains BeO. But, in that case some warning labels are present (at least in russian language)
The best way I've heard to describe the operation of a magnetron is to think of blowing air into an empty bottle, the air resonates in an empty cavity, just as the electron cloud resonates in the cavities of the magnetron as they rotate in the magnetic field...
Pink in Beryllium is merely a added colour, as the oxide itself is white. Not al pink insulators are beryllium oxide, in general it is only used where you need very good thermal performance and a very high insulation resistance, and it is good at this, though very expensive, so in most applications you use a much cheaper aluminia instead.
Yeah, the pink is usually due to chromium oxide. In both cases. Both beryllium oxide and Aluminium oxide are really pure white. Pink or white insulator means nothing to indicate what it is.
I dismantled so many microwaves and i never know that the main body of the magnetron is made of clean copper, so much metal went to the scrapyard for price of scrap instead of millberry copper that i dont want to think about it.. As always really good video, keep it up :)
@@peterzingler6221 several people already said that the newer ones aren't beryllium oxide, but aluminum oxide, like the content creator said. Either way, the blasted thing wasn't damaged in any way, anywhere through the video, clear to the end. And if people are concerned, there are these things called respirators.
Really your video has enriched my knowledge about the magnetron part. Beautiful presentation by you. No words to express my gratitude to you for this video.
I watched the whole video just to hear more of his pronunciation :-) 5:44 "here is the ferayt coOoOorrrr" 6:48 "brasss wayyrrRrrRrrrr"... marvelous, subscribed! :-)
As my mother always used to say when i took something apart "very interesting dear, now lets see you put it back together". Fascinating, thanks for explaining!
@@MaryAnnNytowl My favourite was a broken film cine camera when I was about 11. The little lens was just about the only useful object remaining after all the screws had been removed. :-)
Probably got a little booger on the antenna that shorted it out. That's what the mica window is for so the splatter doesn't get in there and fuck up the magnetron.
Hey excellent job cutting that apart yes at very high frequencies ac ground and positive float in between. And explaining it also. Watched a video on how they are made quite interesting. Keep the videos coming
2.45 GHz isn't used because it is the best frequency to heat water. The main reason is that the size of the magnetron as well as the oven chamber scale with the wavelength. Commercial microwave ovens, where size and weight isn't as much of an issue, sometimes run at lower frequencies (
Not only that, little things won't heat at all. At my old shop I had a crappy oven to heat water to make instant coffee. One day I put the jar of water in (use a jar not a nice cup cause of lime mess) and noticed a little spider inside as I closed the door and hit the timer. Die spider....what .......it's still moving, steamed up and still moving. Ding, hot water and a live spider. I took tissue paper to the spider and had coffee. Lesson: dirty insides of microwave ovens are NOT sterilized in any way shape or form and there is a fan blowing that stuff around your food! Little bits of meat blast off and germs, oh my!
@@echodelta9 Germs flying around aren't an issue. The same thing happens outside of the microwave anyway. If they multiply enough, then they can become a risk, but that's due to inproper storage. If you have a microwave oven with a rotating dish, the waves will form a static pattern within the chamber. The spider had the "luck" of being in one of the non-irradiated spots. There are also ovens that don't have a rotating dish. Those have a microwave "scrambler" that makes the waves move around a little and you get fewer hot and cold spots.
@@echodelta9 what did the spider do to you, except try to catch bugs that cause people more problems? Flies of all varieties, for example, spread more germs than any microwave would do. 🙄 Should've let the spider go in a cabinet or something and let him do his job. 🙄
Excellent DGW :o) Spark plugs before WWII used to have insulators the same colour as the rf output insulator here - and they were mostly made from aluminium oxide also I believe.
If it was up to me to come up with something like this, we'd still be cooking in pots over a fire. My hat goes off to anyone that actually understands how this stuff works. 🤯
If you watch his Czech language videos, his English will make sense to you. Personally I love Diodes English, it helps me relax. I have a Czech friend who's English is very different to Diode's. My friend over-pronounces the letter U as an ooo sound but thats about it. Its fun to get him to say duck, pluck and plus as they come out as doook, ploook and ploos. Very cute :) lol Have you tried rolling your R's, it's next to impossible for me as an English man. Diode rocks at rolling R's :D love it :)
Ive extracted magnetrons from two microwaves from the scrapyard for their magnets and safely put aside the core with the beryllium just this morning, and your thumbnail surely gave me a shock! Sure enough, it worked cause here I am watching and liking 😁 Love your work DGW! Just as the video said, please avoid damaging the beryllium sleeves at the magnetron core!
Sir in the first place we bow down unto you and seek your Blessings as you are an Eminent Teacher, a one Man Institution or a University. I am a Senior Citizen age 70 yet I learn alot from you. You subjective Explantion with so much of clarity and indepth knowledge in details can amaze any student and if one has a bent of mind for learning you are an Ocean. I want to see your face which always remains hidden but Sir please oblige us and in one of your Videos tell us all about yourself for we worship you for your knowledge. I sincerely Thank You from my Heart and Pray to God that you lead a healthy and have a life span of 100 years to benefit your students.
You speak English with a fascinating accent that I have never heard before. Where was your home and what was your first language? Outstanding description of how a cavity magnetron functions!!! Fifty seven years ago, I used to salvage discarded tube-type black and white television sets from the curbs of the streets of Detroit and I salvaged their tubes, capacitors and resistors to fabricate a 'ham' (amateur radio) transmitter out of scrap. The era of those of us who constructed working radio sets from scrap is gone. Behold the new era! I thank you for your technical explanation of our new frontier. Clinton
I live in the Czech Republic and my first language is Czech. People usually never get rid of a strong accent if they start learning a foreign language too late. Only kids can learn to speak as natives do. When I was young, I've also taken apart some vacuum tube TVs and radios and build something from them. Nowadays it's a different era, but there's still a lot of things people can build or fix. The things we used to build are now cheap and readily available, but there are things that make sense to build nowadays, and those were impossible in the past.
10:30 those Dremel wheels are usually more for cutting harder metals like aluminum, steel, and iron, they don't cut well through soft materials either due to build up of dust sticks around where you're cutting or the softer particles will gum the blade especially with plastics, they make reinforced wheels but those things tend to cost too, plus they tend to be thicker, so you lose a little precision depending on what you're cutting
Correct me if i am wrong but copper should be harder than aluminium but softer than steel at least that what i have been experiencing when cutting steel/copper with angle grinder althou dremel and discs for it could be different. have an awesome day Sincerely random internet stranger, sorry for my bad english.
@@milanhlavacek6730 well angle grinders wheels tend to be much thicker, the Dremel wheels cut through aluminum, steel, and iron fairly easily, I'd say copper is softer than aluminum, alteast its much more ductile than aluminum, copper is soft enough to cut with a steel blade (with pipe they make cutters that screw on and you twist and it simply cuts through) it has a tendency to melt and stick around the cutting area, and gums the wheel as you see when he puts pressure the friction drastically cuts the Dremel speed, using less pressure and keeping the rpm high like he described works that's what I do though id have a piece of scrap steel or something so if the wheel feels gummy I just grind it on that to clean it up a little English is fine btw
@@Clancydaenlightened thank you for taking the time to explain, im like 14 so i have next to no experience in working with metals, there is lot to learn and people like you that take the time to explain to random strangers on internet are quite rare btw im from Czech republic and like in 9 grade so i dont know that much english have a nice day
Beryllium oxide is really only dangerous if your machining it or doing some other process thats creating lots of dust. Just cracking the ceramic probably wont be an issue. We used beryllium alloys as well as ceramics and our in-house machinist had to take some special precautions when turning or milling it.
17:48 Magnetrons are velocity modulated AFAIK. As the electrons circulate in the gap their velocity increases and decreases as they go past the cavities and they bunch up, which then transfers energy to the anode groups. The dimensions of the tube itself then determine the operating frequency. The velocity of the electrons themselves is too slow for direct operation at microwave frequencies.
Those two rings at the centre are EQUALISER RINGS to balance out the " capacitor" voltages on those ten parallel conceited tuned circuits. They also use them in larger generators. That output strap is in fact a magnetic loop or a magnetic probe, which is not floating on its own, but acting as a tapping on an autotransformer with a given ratio so that the output impedance is lowered as it feeds the load. Each of those resonant circuit may be looked upon as a flute where the open end has a wind blowing across it, The fact that the electron is negatively charges then as it approach's one end that end goes negative, then as it starts leaving it, that end will start ging positive while the next end that is being approached will go negative and the tuned circuit will set up and determine the resonant frequency. where the equaliser ring will set up a state where all the tuned circuits are forced to resonate at the same frequency. The space below and above the radially projected inductive part of the exist to allow the magnetic field LOOPS to form and thus they will excite the magnetic probe by causing the loop of magnetic fields to go through it where a curling electric field will be generated in the copper of the magnetic probe. All the Gradients and divergences and curls mentioned in Maxwell equations may easily be followed in that magnetron. I like the manner in which they used rectangular copper radial parts to increase the capacity between the faces. Note that the 6 Volts feeding the heater are superimposed on the voltage of the " diode doubler pump which probably takes the cathode to minus 6,000 volts pulse. The manner in which the radial parts are held on the circumference is an ingenious riveting system and no brazing is done. The engineering of that magnetron looks primitive but it is effective as it is not a high fidelity amplifier to reproduce music but shear power to heat food is all that is required. and a few harmonics will not hurt in this case. The presentation is good, but the speaker should spend some time listening to normal English language as spoken in England, I spent 16 years in England travelling from Dover, Portsmouth, Devonport, Cornwall Par, Wales , Carlyle, Lake district, Scotland, Barnbarough, Holy Island, Newcastle and Manchester and Nottingham, listening to the different English accents, and sixteen years later headed back home, I would suggest that everyone who presents public videos in the English language should spend a few hours listening to the Oxford University debates. They do not exactly speak the King's or the Queen's English , but it would enhance this presentation. If one is to go public with technical contents , one should also consider the effect of the spoken delivery. Note that it is not always wise to use power tools and with me being a very old man, I would not have used that dermal, grinder, but a good old hacksaw which I had for over 75 years since I was ten years old would have made a better job of dissecting that magnetron. How a magnetron is excited analogy. ruclips.net/video/5tTkDQnT95g/видео.htmlsi=5rD8KGjWz7vy54zU ruclips.net/video/zKTS95KOrOI/видео.htmlsi=ncN-2HCduKM4PDLk .ruclips.net/video/E18iLLioN6o/видео.htmlsi=RyRc6nrJXrIbcAAt .
I absolutely disagree with you. British English with its 'stop and go' style is the ugliest English you can use in this world. When I hear you say "often" in London accent I get chills. Even an Indian accent is better than a British one. And the best is the smooth American accent. Every Brit should learn it.
@@omsingharjit Microwave ovens are very well shielded, so only maybe a few mW of microwaves can make it out. Also, wifi and such are modern digital protocols, so they can tolerate quite a bit of disturbances without much issue.
I believe that the cathode filament still is isolated from the magnetron body / anode. Thereby the cathode which has the high (negative) potential cannot directly influence the voltages at the output or anode area in general.(see 17:30) I would believe that the output impedance is lower than with normal electron tubes. Judging by the size of the output connection there might be several amperes of RF power, which correlates to probably less than 100 volts of voltage at that point. Thanks again for a great video!
First of all this is a good video! About radiation precaution advice I believe the same that you said. And for example I mentioned the smoke detector that contains a radio active substance like Americium. Naturally there is the necessary signal of the radioactive substance. So is it possible microwave that is for food to not have the same signal? I think not. Instead there is only the Lightning strike that indicates high voltage. Of course there is beryllium oxide (pink layer)but as you said is toxic only if you break it and inhale the dust! The thorium tungsten alloy cathode is slightly radio active possible less than Americium or almost like ground.
Well well well. Rumor has it that this is now the definitive video on magnetrons. Look like it’s time to fire up the old camera and CGI software and defend my honor.
I found it interesting that you were able to measure some form of ionizing radiation from thoriated tungsten, even though it was in a plastic sleeve, as it's typically an alpha emitter. Either way, a neat tear-down. For those wondering about the 'black magic,' as an example: at 2.45 GHz, a mere 0.5 pF capacitance has a reactance of 130 Ω, and there is actually much more than that going on. }:)
I appreciate your cat's genuine interest in physics! By the way, may I ask what you do for living? I'm a physicist and I like all of your videos very much!
Love your Geiger counters, that looks like a backlight transformer from a LCD TV used for the high voltage supply? And a PIC based counter? Video please!!!
Good guess. It actually comes from a CCFL tube base (which is basically the same thing). See his website for details on this and other projects: danyk.cz/gm_ind_en.html
I think the insulators are aluminium oxide too, but I can't give you a guarantee on that. I still handle them with care, and if I would break it, I would consult a specialist with the sample. But as you said, it is unlikely to see more expensive and harder to work beryllium oxide in consumer product, where the aluminium oxide will do very good job instead. One way to have higher confidence is check the density (weight / volume), and compare with tables, or use XRF.
How do you know so much. Bow to you and your knowledge !!. TOday, I scrapped my microwave, but due to lockdown, I had ample time. So, I separated the metals, plastic etc to that scrap dealer can handle them easily (scrap is sold in India, not just thrown in bins). I can recover some of the money of microwave oven, if I separate the steel, copper etc and then sell to scrap dealer.
Interesting. Never seen the inside of a cheaper modern magnitron. Early ones did not have the rings and the anode cavities were a solid part, not assembled from bars. I think the rings are for mechanical stability of this design to prevent de-tuning if the anode overheats. Older ones were suspectable to loss of efficiency (low power output) and high power use resulting in tube overheating.
When I used to repair microwaves back in the 1990's, several of the training courses I attended warned us about beryllium oxide in the magnetron, which I ignored as they were internal training courses. It was not until I attended several official courses, one from Sharp, and especially one from Panasonic UK, a full seminar training course, where once again they stressed about the dangers of the beryllium oxide contained within the magnetron that it really sunk in how dangerous they are. The RULE is, if the insulator is PINK it contains beryllium oxide (as beryllium oxide is pink) , if it is WHITE then it is ALUMINIUM based. Older microwaves before about 2005 used beryllium oxide, but have noticed a switch to Aluminium over the years since. I have also noticed some within the last year with BLUE insulators?... If you have a pink insullator ind you break it and inhale the dust, you are asking for berylliosis of the lungs...
Beryllium oxide is NOT pink, it is white and not easily distinguishable from aluminum oxide, which has a higher density. It is used because it is one of the best conductors of heat while being an excellent electrical insulator (only diamond has better properties). It is also widely used in the construction of high power RF power transistors and other high power semiconductors, which carry the same warnings. Until the 1950's it was also widely used as a component of the fluorescent coating inside fluorescent tubes.
I would expect a training course to be full of "cover our asses" material but not necessarily that hot on facts. (having attended and helped create many training courses) I'd love to hear from a production engineer at the factory where they make the magnetrons, then we really would know the facts. In the meantime, I'm assuming it's beryllium oxide and proceeding with caution, but insisting on holding on to me scepticism. We need Cody Don Reeder to zap a load with his x-ray spectrometer!
@@petermarchionda I probably inhaled "a tonne" of fluorescent tube gunk in my childhood. Thinking of our poor methodology for doing teardowns back then.
Beryllium oxide is used as sockets for highpower tubes in ham radio amplifiers because they are very thermally conductive. As long as a file or other means does not create dust that could be breathed in its considered safe.
Ok my second time back here after thinking about that copper arrangement in the middle - which is why I'm on your page bro. I'm holding one and haven't scratched it to see it's copper yet - and because shit happens I just wanted to know what was in side. Now I'm glad you are here because I was going to cut the other end off first and I would have found the "boring light bulb" bit and missed out on the "Antenna" Now back to the 2.45 GHz and that copper top bit you ripped off. Suggested observation A. there is a ring capacitor - you can't get away from those two rings and Cap's everything down to that gap which means it's an "Antenna"! B. How those chambers work is going to be the magnet flows. [has to be look at the flow] This is working in the same way you can drop an iron bar in acid and paint copper direct on to it using Amps / Volts and the medium is the acid. Here the Medium is the stressed Magnetic Field - the distance of those magnets and going to be right on a stress point and those copper shapes give it exactly what it wants to effect electrons [just like an Air coil ] without iron. Look at it, Everything between the magnets is copper or alli and of those "Copper controls Magnets" and therefore the alli is to control backfeed - collectors or reflectors . So they're compressing microwaves into they 14mm x 12mm wide copper stub under the top then out through that 5mm hole at the top. When you have a look at the fine edge of that 14mm stub in the middle on the fine edge in the 5mm part under the hole in the cap, you can see the copper has been stolen - !IT'S MOVED SOME COPPER! using a magnet and pressure and the 2.45 is as you say only water related. Right! I need to cut the end you did off first - Thanks. Have you got an operating Tesla Coil - and Air Coil where a base frequency sets off a simple "child on a swing" effect controlled by a single power supply and a crude capacitor and spark? The medium there is air and the magnets are replaced with frequency. How may times do you push that child and right time per second . When you go Too High the Tesla Coil will begin to spark from the cap. "STATIC" is Achieved just BEFORE the spark at the cap of the coil. STATIC - is a very fluid state where MATTER can be influenced by magnetic. Hand's up anyone who can tell me where the Largest Working Tesla Coil in The World is? Speak up anyone who can now name the Largest Twin Tower Tesla Coil ever constructed?
Btw. the radiation isn't generated by electrons hitting the anode. The electrons circle the cathode passing by the cavities. This creates a resonant electric field which in turn influences the electrons so they bunch up while circling, increasing the resonance amplitude further. A part of that is tapped of by the antenna. Electrons only hit the anode if they lost too much kinetic energy.
Some time ago I first saw one of your videos. You used an ugly soldering iron and crude hand tools. I immediately thought something like "This guy is so amateurish." The more DiodesGoneWild videos I watched the more I realized how wrong that first impression was. Your straightforward style and the way you explain circuits in plain language is wonderful. You bring the subject of electronics down to earth, not hiding it behind complicated language or fancy equipment few can afford. Rather, using found and fabricated tools you say to your audience "You do not need a 200 dollar power supply, an 800 dollar oscilloscope, and a lab full of specialized tools to start learning and playing with electronics." Too many channels seem to say just the opposite. I am glad that you discuss safety while still doing things "the book" calls unsafe. We all do these things in real life but worry that people unfamiliar with how to stay alive will jump in unaware. Your cautions are well placed and helpful I'm sure.
I have been surprised how much I have learned from your videos. Today as I watched your description of your understanding of the magnetron operation for just a moment a light went on in my mind. I suddenly had a glimpse of understanding of the "How." I have read about the function of magnetrons and their fascinating history (A Secret Weapon, highly classified!). Still when it came to How it actually resonated always stayed in my mind as "...and then Magic happens." Today I think I understand and will go back to the books.
That alone is worth boosting my Patreon support. I encourage others to give as they can to support DGW's continued efforts.
Thanks for this nice message and for your support ;)
I felt the same but quickly realized I was learning more from this channel than any other.... Best channel😁👍
I concur!
@@DiodeGoneWild I'm actually here because of ElectroBOOM: he mentioned your video about that shockingly dodgy electrocuting shower head.
I couldn't agree more!
I also found the equipment used a little dodgy at first, and thought he barely knew what he was doing, but know i feel quite the opposite now, no doubt he knows what he's doing and he is impressively good at communicating it.
But as they say: "If you can't explain it simply, you don't understand it"
Thanks to DGW for the fantastic videos :)
A friend of mine whilst preparing to open a RADAR museum was given permission to look through the GEC research laboratories in Wembley after they closed the site. He discovered all the Magnetron prototype blueprints, correspondence marked top secret, production drawings etc...The whole history of the Magnetron from the late 30s through to the late 40s boxes full.
In the event the museum idea fell through , yet nobody seemed interested in the complete history of the invention that arguably saved the world. The Imperial War museum didn't want them etc..They are still sitting in cardboard boxes. I have some scans. They also made and developed some great audio gear (like KT88 ) along with dozens of other amazing things etc.
Great video as usual. Love your channel.
Wow! Interesting stuff. I hope it is at least preserved. One day we will want to know where our technologies came from.
It would be a great idea to digitally preserve the whole stack, but that would fill up your schedule for the next couple of weekends, no doubt.
@@suey1690 My time is my own. If these are at risk of disappearing it could be a worthy mission.
Dear Martin D A,
As a physicist and researcher working on microwave plasmas, your story catches my attention. Such files would be invaluable for the history of science but also for teaching at the university (particularly for electrical engineers, physicists). I assume that such files aren‘t classified any longer (besides that commercial magnetrons are obviously under patents protection and actually so cheap to produce that no one would spend time to design one nowadays). Making such historical files, in a way or another, available would save prior knowledge to posterity and shine light on the (to my knowledge) not so well described physical principles that led to their design. Is there any way to access these files and to see if they could be made open to the scientific community? Thanks in advance for your reply!
Kind regards,
Emile Carbone
@@eadcarbone I'm sure it could be arranged. I will ask. I will let you know shortly. Thanks Emile.
This is hands down the most informative electronics channel in the whole internet.
I follow every electronic channel in RUclips (some are so small they might have 50 or so subscribers) i watch hundreds of videos about electronics and I'm not exaggerating when I say it.
Thank you very much sir.
This is the most interesting explanation (and teardown as well) I've ever met on this topic.
Big thanks!
Beryllium oxide was very common a long time ago, but most modern magnetrons do not use it anymore, but use aluminum oxide instead. From what I have been told- again, I can't say that this is fact- a pink insulator indicates that it's a newer aluminum oxide insulator. A white insulator could be anything, and should be assumed to be beryllium, especially on a newer unit, because the pink color- as I've heard- indicates that it's aluminium oxide, with chromium oxide added. Once again, this is information I've learned from a third party, I can't vouch for its accuracy. What is certain is beryllium oxide WAS used in older magnetrons, and may still occasionally be used today, though most have switched to aluminum oxide.
Pink color makes sense when sapphire is made of aluminum oxide hence the pink color on cmm probe tips. I wonder if that's its spectroscopy color too? How they detect elements on planets/stars
That's weird, I just read online that pink is beryllium
bro i have just smashed a white insolation and inahled it accidently :(
@@picanazo420 Nice
@@picanazo420*Dumb ways to die*
doing a physics lesson in a second language is impressive by itself......of course
Excellent information .Thank you sir
He’s so close to getting the accent done well. He just needs to work on the ending of his words
He is quite an impressive guy😊, love his videos.
I like his accent
I thought First😊 was Scottish
Amazing job, thank you. For the first time ever, I have an intuitive feel for how the magnetron works, with some great insights.
In some old russian owens, "military grade" magnetron design used, and yes, that magnetrons contains BeO. But, in that case some warning labels are present (at least in russian language)
Just after last video I got very interested in precisely this: what is inside a magnetron!! Thank you for the video Diode! Love your content!
My head is swirling just as the electrons inside the magnetron! Great video!
Great analyses and explanation of the magnetron. First time I have seen one taken apart. Very interesting design. Keep up the excellent video's DGW.
The best way I've heard to describe the operation of a magnetron is to think of blowing air into an empty bottle, the air resonates in an empty cavity, just as the electron cloud resonates in the cavities of the magnetron as they rotate in the magnetic field...
This honestly makes sooo much more sense now.
9:00 Man, your cat is more useful than most of the tools in my workshop.
Noticed it is RARE to read SO MANY positive comments regarding someone explaining electrical things on RUclips.... Well done
This is the best, most comprehensive and complete explanation of a magnetron that I have seen, thank you. :-)
Pink in Beryllium is merely a added colour, as the oxide itself is white. Not al pink insulators are beryllium oxide, in general it is only used where you need very good thermal performance and a very high insulation resistance, and it is good at this, though very expensive, so in most applications you use a much cheaper aluminia instead.
Yeah, the pink is usually due to chromium oxide. In both cases. Both beryllium oxide and Aluminium oxide are really pure white. Pink or white insulator means nothing to indicate what it is.
I dismantled so many microwaves and i never know that the main body of the magnetron is made of clean copper, so much metal went to the scrapyard for price of scrap instead of millberry copper that i dont want to think about it..
As always really good video, keep it up :)
Well. Beryllium oxide is also there a lot so not worth the risk
@@peterzingler6221 several people already said that the newer ones aren't beryllium oxide, but aluminum oxide, like the content creator said. Either way, the blasted thing wasn't damaged in any way, anywhere through the video, clear to the end. And if people are concerned, there are these things called respirators.
Really your video has enriched my knowledge about the magnetron part. Beautiful presentation by you. No words to express my gratitude to you for this video.
Enjoyed the video and your knowledge in Black Magic.
I watched the whole video just to hear more of his pronunciation :-)
5:44 "here is the ferayt coOoOorrrr"
6:48 "brasss wayyrrRrrRrrrr"... marvelous, subscribed! :-)
As my mother always used to say when i took something apart "very interesting dear, now lets see you put it back together". Fascinating, thanks for explaining!
Can't you hear his cat saying exactly this??)
@@jkobain Indeed, that is purrfectly clear :-)
Ah, now that sounds familiar - my mother used to say the same thing. 😄
@@MaryAnnNytowl My favourite was a broken film cine camera when I was about 11. The little lens was just about the only useful object remaining after all the screws had been removed. :-)
Magnatron: Guess i'll die
- Live for the swarm!
Probably got a little booger on the antenna that shorted it out. That's what the mica window is for so the splatter doesn't get in there and fuck up the magnetron.
Hey excellent job cutting that apart yes at very high frequencies ac ground and positive float in between. And explaining it also. Watched a video on how they are made quite interesting. Keep the videos coming
Top Explaind ! The Best in RUclips so far.
this is it, here is the man who knows his work, pure explanation you the best🤙🤙
2.45 GHz isn't used because it is the best frequency to heat water. The main reason is that the size of the magnetron as well as the oven chamber scale with the wavelength. Commercial microwave ovens, where size and weight isn't as much of an issue, sometimes run at lower frequencies (
Not only that, little things won't heat at all. At my old shop I had a crappy oven to heat water to make instant coffee. One day I put the jar of water in (use a jar not a nice cup cause of lime mess) and noticed a little spider inside as I closed the door and hit the timer. Die spider....what .......it's still moving, steamed up and still moving. Ding, hot water and a live spider. I took tissue paper to the spider and had coffee. Lesson: dirty insides of microwave ovens are NOT sterilized in any way shape or form and there is a fan blowing that stuff around your food! Little bits of meat blast off and germs, oh my!
@@echodelta9
Germs flying around aren't an issue. The same thing happens outside of the microwave anyway. If they multiply enough, then they can become a risk, but that's due to inproper storage.
If you have a microwave oven with a rotating dish, the waves will form a static pattern within the chamber. The spider had the "luck" of being in one of the non-irradiated spots.
There are also ovens that don't have a rotating dish. Those have a microwave "scrambler" that makes the waves move around a little and you get fewer hot and cold spots.
@@echodelta9 what did the spider do to you, except try to catch bugs that cause people more problems? Flies of all varieties, for example, spread more germs than any microwave would do. 🙄 Should've let the spider go in a cabinet or something and let him do his job. 🙄
Excellent DGW :o) Spark plugs before WWII used to have insulators the same colour as the rf output insulator here - and they were mostly made from aluminium oxide also I believe.
Omg, what an unusual accent 😂! But this explanation is one of the best I have seen!❤
If it was up to me to come up with something like this, we'd still be cooking in pots over a fire.
My hat goes off to anyone that actually understands how this stuff works. 🤯
Very good esplanation about inside Magnetron. Thank You Sir.
- There are some screeeews, let's unscreeew it! XD
If you watch his Czech language videos, his English will make sense to you. Personally I love Diodes English, it helps me relax. I have a Czech friend who's English is very different to Diode's. My friend over-pronounces the letter U as an ooo sound but thats about it. Its fun to get him to say duck, pluck and plus as they come out as doook, ploook and ploos. Very cute :) lol Have you tried rolling your R's, it's next to impossible for me as an English man. Diode rocks at rolling R's :D love it :)
@@JohnnyX50 you said it like I mind his accent. Not at all!
here is my cat of coourrrse
@@santi308 that's niiiice! XD
@@jkobain quite dodgy
What a COMPLEX could be a SIMPLE microwave oven. Thanks for your great video and explanation.
Finally a new video. Where have you been man? I keep checking for new materials.
Ive extracted magnetrons from two microwaves from the scrapyard for their magnets and safely put aside the core with the beryllium just this morning, and your thumbnail surely gave me a shock! Sure enough, it worked cause here I am watching and liking 😁 Love your work DGW!
Just as the video said, please avoid damaging the beryllium sleeves at the magnetron core!
Sir in the first place we bow down unto you and seek your Blessings as you are an Eminent Teacher, a one Man Institution or a University.
I am a Senior Citizen age 70 yet I learn alot from you.
You subjective Explantion with so much of clarity and indepth knowledge in details can amaze any student and if one has a bent of mind for learning you are an Ocean.
I want to see your face which always remains hidden but Sir please oblige us and in one of your Videos tell us all about yourself for we worship you for your knowledge.
I sincerely Thank You from my Heart and Pray to God that you lead a healthy and have a life span of 100 years to benefit your students.
You speak English with a fascinating accent that I have never heard before. Where was your home and what was your first language? Outstanding description of how a cavity magnetron functions!!!
Fifty seven years ago, I used to salvage discarded tube-type black and white television sets from the curbs of the streets of Detroit and I salvaged their tubes, capacitors and resistors to fabricate a 'ham' (amateur radio) transmitter out of scrap. The era of those of us who constructed working radio sets from scrap is gone. Behold the new era!
I thank you for your technical explanation of our new frontier.
Clinton
I live in the Czech Republic and my first language is Czech. People usually never get rid of a strong accent if they start learning a foreign language too late. Only kids can learn to speak as natives do. When I was young, I've also taken apart some vacuum tube TVs and radios and build something from them. Nowadays it's a different era, but there's still a lot of things people can build or fix. The things we used to build are now cheap and readily available, but there are things that make sense to build nowadays, and those were impossible in the past.
19:08 36 uR/h, not great, not terrible!
10:30 those Dremel wheels are usually more for cutting harder metals like aluminum, steel, and iron, they don't cut well through soft materials either due to build up of dust sticks around where you're cutting or the softer particles will gum the blade especially with plastics, they make reinforced wheels but those things tend to cost too, plus they tend to be thicker, so you lose a little precision depending on what you're cutting
Correct me if i am wrong but copper should be harder than aluminium but softer than steel at least that what i have been experiencing when cutting steel/copper with angle grinder althou dremel and discs for it could be different. have an awesome day Sincerely random internet stranger, sorry for my bad english.
@@milanhlavacek6730 well angle grinders wheels tend to be much thicker, the Dremel wheels cut through aluminum, steel, and iron fairly easily, I'd say copper is softer than aluminum, alteast its much more ductile than aluminum, copper is soft enough to cut with a steel blade (with pipe they make cutters that screw on and you twist and it simply cuts through) it has a tendency to melt and stick around the cutting area, and gums the wheel as you see when he puts pressure the friction drastically cuts the Dremel speed, using less pressure and keeping the rpm high like he described works that's what I do though id have a piece of scrap steel or something so if the wheel feels gummy I just grind it on that to clean it up a little
English is fine btw
@@Clancydaenlightened thank you for taking the time to explain, im like 14 so i have next to no experience in working with metals, there is lot to learn and people like you that take the time to explain to random strangers on internet are quite rare btw im from Czech republic and like in 9 grade so i dont know that much english have a nice day
I love your lessons! You are in absolute the most interesting you-tuber in this charming subjects!
A magnetron is quite facinating piece of alien technology even for me as an electrician.
Who ever Designed the Magnetron is a Genius...
Beryllium oxide is really only dangerous if your machining it or doing some other process thats creating lots of dust. Just cracking the ceramic probably wont be an issue. We used beryllium alloys as well as ceramics and our in-house machinist had to take some special precautions when turning or milling it.
You are an excellent teacher!
MagnetronGoneWild
I cut open one of these with a hacksaw by hand once. It took almost 5 hours to cut open fully
i learn a lot from you and you make it very easy , thank you .
Such a poetic and musical accent. I could listen to this man reading the telephone directory!
Many thanks for sharing this the tear down and operation it's fascinating I've always wanted to know about them hats off to the designers....
very good. nothing like taking something apart to better understand how it works.
Yet another nice video. Magnetrons are part of our lives but scary in various ways.
Excellent Presentation! Thank You.
Full postmortem of Magnetron. Lots of info in this video. Thank you very much.
Best channel ever...
Great explanation and loved your diy GM counters too!
17:48 Magnetrons are velocity modulated AFAIK. As the electrons circulate in the gap their velocity increases and decreases as they go past the cavities and they bunch up, which then transfers energy to the anode groups. The dimensions of the tube itself then determine the operating frequency. The velocity of the electrons themselves is too slow for direct operation at microwave frequencies.
Those two rings at the centre are EQUALISER RINGS to balance out the " capacitor" voltages on those ten parallel conceited tuned circuits. They also use them in larger generators. That output strap is in fact a magnetic loop or a magnetic probe, which is not floating on its own, but acting as a tapping on an autotransformer with a given ratio so that the output impedance is lowered as it feeds the load.
Each of those resonant circuit may be looked upon as a flute where the open end has a wind blowing across it, The fact that the electron is negatively charges then as it approach's one end that end goes negative, then as it starts leaving it, that end will start ging positive while the next end that is being approached will go negative and the tuned circuit will set up and determine the resonant frequency. where the equaliser ring will set up a state where all the tuned circuits are forced to resonate at the same frequency.
The space below and above the radially projected inductive part of the exist to allow the magnetic field LOOPS to form and thus they will excite the magnetic probe by causing the loop of magnetic fields to go through it where a curling electric field will be generated in the copper of the magnetic probe. All the Gradients and divergences and curls mentioned in Maxwell equations may easily be followed in that magnetron. I like the manner in which they used rectangular copper radial parts to increase the capacity between the faces.
Note that the 6 Volts feeding the heater are superimposed on the voltage of the " diode doubler pump which probably takes the cathode to minus 6,000 volts pulse. The manner in which the radial parts are held on the circumference is an ingenious riveting system and no brazing is done. The engineering of that magnetron looks primitive but it is effective as it is not a high fidelity amplifier to reproduce music but shear power to heat food is all that is required. and a few harmonics will not hurt in this case.
The presentation is good, but the speaker should spend some time listening to normal English language as spoken in England, I spent 16 years in England travelling from Dover, Portsmouth, Devonport, Cornwall Par, Wales , Carlyle, Lake district, Scotland, Barnbarough, Holy Island, Newcastle and Manchester and Nottingham, listening to the different English accents, and sixteen years later headed back home, I would suggest that everyone who presents public videos in the English language should spend a few hours listening to the Oxford University debates. They do not exactly speak the King's or the Queen's English , but it would enhance this presentation. If one is to go public with technical contents , one should also consider the effect of the spoken delivery.
Note that it is not always wise to use power tools and with me being a very old man, I would not have used that dermal, grinder, but a good old hacksaw which I had for over 75 years since I was ten years old would have made a better job of dissecting that magnetron.
How a magnetron is excited analogy.
ruclips.net/video/5tTkDQnT95g/видео.htmlsi=5rD8KGjWz7vy54zU
ruclips.net/video/zKTS95KOrOI/видео.htmlsi=ncN-2HCduKM4PDLk
.ruclips.net/video/E18iLLioN6o/видео.htmlsi=RyRc6nrJXrIbcAAt
.
I absolutely disagree with you. British English with its 'stop and go' style is the ugliest English you can use in this world. When I hear you say "often" in London accent I get chills. Even an Indian accent is better than a British one. And the best is the smooth American accent. Every Brit should learn it.
Because wireless communication snd microwave ovens magnetrons frequency are same it can interfere with smartphone ??
its 50MHz apart
@@mzflighter6905 so what if both will same ? At how much distance it will affect device with only single bare magnetron !!??
I mean there is the distance where it has to interfere with/ damage the circuitry because of the enormous power density
@@omsingharjit Microwave ovens are very well shielded, so only maybe a few mW of microwaves can make it out. Also, wifi and such are modern digital protocols, so they can tolerate quite a bit of disturbances without much issue.
@@Basement-Science i know that's why i used that word
" bare magnetron "
I believe that the cathode filament still is isolated from the magnetron body / anode. Thereby the cathode which has the high (negative) potential cannot directly influence the voltages at the output or anode area in general.(see 17:30)
I would believe that the output impedance is lower than with normal electron tubes. Judging by the size of the output connection there might be several amperes of RF power, which correlates to probably less than 100 volts of voltage at that point.
Thanks again for a great video!
Thoroughly enjoyed it and I have learnt a lot many thanks
4:16 "but I still have to cover my ass..." this is really going to be wild :D
Hahaha 😂😂
It is used in czech quite often, it has a different meaning ofc. :)
@@What8Bit I am Slovak...
First of all this is a good video!
About radiation precaution advice I believe the same that you said. And for example I mentioned the smoke detector that contains a radio active substance like Americium. Naturally there is the necessary signal of the radioactive substance. So is it possible microwave that is for food to not have the same signal? I think not. Instead there is only the Lightning strike that indicates high voltage. Of course there is beryllium oxide (pink layer)but as you said is toxic only if you break it and inhale the dust!
The thorium tungsten alloy cathode is slightly radio active possible less than Americium or almost like ground.
Awesome vid bud. I really like these. Do u have a doctorate in the electronic field ? Your knowledge is far beyond many.
18:55 if the filament emits alpha radiation some of it may be shielded by the plastic wrapped around the wire pieces I assume..
True
Well well well. Rumor has it that this is now the definitive video on magnetrons. Look like it’s time to fire up the old camera and CGI software and defend my honor.
Now that you know what's inside :-)
& Catch the Berilyum vs. CrO3/polycrystalline ruby discussion further below.
Good work brother
I really appreciate watching your videos and I like to learn from your channel
DiodeGoneWild -Where are you from(country)? You have the best knowledge about electrotechnics. I could learn a lot from you. :-)
he's from the Czech Republic
A good explanation, very interesting, thank you.
I found it interesting that you were able to measure some form of ionizing radiation from thoriated tungsten, even though it was in a plastic sleeve, as it's typically an alpha emitter. Either way, a neat tear-down. For those wondering about the 'black magic,' as an example: at 2.45 GHz, a mere 0.5 pF capacitance has a reactance of 130 Ω, and there is actually much more than that going on. }:)
its reactance is 1/angularspeed*capacitance at that frequency it should be much smaller maybe you are confusing the inductors reactance?
This guy sounds like he's singling. Nice video!
Wonderful episode Thanks.
VERY good video! Thank you and keep up the good work!
Very helpful video 👍
Thank you for debunking the Beryllium Oxide myth. It's like an urban legend that wouldn't just go away
First time watching this channel....
WOW, what an accent!
This helped a lot.
Thanks
Don't you ever try to die! Who am I going to watch during breakfast? :-)
I appreciate your cat's genuine interest in physics! By the way, may I ask what you do for living? I'm a physicist and I like all of your videos very much!
Thank you for a great video
Love your Geiger counters, that looks like a backlight transformer from a LCD TV used for the high voltage supply? And a PIC based counter? Video please!!!
Good guess. It actually comes from a CCFL tube base (which is basically the same thing). See his website for details on this and other projects: danyk.cz/gm_ind_en.html
I think the insulators are aluminium oxide too, but I can't give you a guarantee on that. I still handle them with care, and if I would break it, I would consult a specialist with the sample. But as you said, it is unlikely to see more expensive and harder to work beryllium oxide in consumer product, where the aluminium oxide will do very good job instead. One way to have higher confidence is check the density (weight / volume), and compare with tables, or use XRF.
Yeah... really XRF is probably the only way to be sure. Which is a pity, because HAVE YOU SEEN THE PRICE of even a crappy handheld unit?
How do you know so much. Bow to you and your knowledge !!.
TOday, I scrapped my microwave, but due to lockdown, I had ample time. So, I separated the metals, plastic etc to that scrap dealer can handle them easily (scrap is sold in India, not just thrown in bins). I can recover some of the money of microwave oven, if I separate the steel, copper etc and then sell to scrap dealer.
Hi! you are doing good job and explained very well
Great video - very informative, and understandable. :D
What if you increase its HT voltage , what affect will occur ??
Change frequency or just power ?
Interesting. Never seen the inside of a cheaper modern magnitron. Early ones did not have the rings and the anode cavities were a solid part, not assembled from bars. I think the rings are for mechanical stability of this design to prevent de-tuning if the anode overheats. Older ones were suspectable to loss of efficiency (low power output) and high power use resulting in tube overheating.
where can i find a image of old magnetrons? i really want to look inside one of those
Happy Thanksgiving from Texas!
Stay safe...as you can LOL
Great video as usual ! TNX 4 upload !
When I used to repair microwaves back in the 1990's, several of the training courses I attended warned us about beryllium oxide in the magnetron, which I ignored as they were internal training courses. It was not until I attended several official courses, one from Sharp, and especially one from Panasonic UK, a full seminar training course, where once again they stressed about the dangers of the beryllium oxide contained within the magnetron that it really sunk in how dangerous they are. The RULE is, if the insulator is PINK it contains beryllium oxide (as beryllium oxide is pink) , if it is WHITE then it is ALUMINIUM based. Older microwaves before about 2005 used beryllium oxide, but have noticed a switch to Aluminium over the years since. I have also noticed some within the last year with BLUE insulators?... If you have a pink insullator ind you break it and inhale the dust, you are asking for berylliosis of the lungs...
Beryllium oxide is NOT pink, it is white and not easily distinguishable from aluminum oxide, which has a higher density. It is used because it is one of the best conductors of heat while being an excellent electrical insulator (only diamond has better properties). It is also widely used in the construction of high power RF power transistors and other high power semiconductors, which carry the same warnings. Until the 1950's it was also widely used as a component of the fluorescent coating inside fluorescent tubes.
I would expect a training course to be full of "cover our asses" material but not necessarily that hot on facts. (having attended and helped create many training courses)
I'd love to hear from a production engineer at the factory where they make the magnetrons, then we really would know the facts.
In the meantime, I'm assuming it's beryllium oxide and proceeding with caution, but insisting on holding on to me scepticism.
We need Cody Don Reeder to zap a load with his x-ray spectrometer!
@@petermarchionda I probably inhaled "a tonne" of fluorescent tube gunk in my childhood. Thinking of our poor methodology for doing teardowns back then.
i was wondering is there any way to condense the microwaves into a beam like a laser tube to make it a long range beam?
Those injoulators are soooo danjarooz! XD
I totally adore this guy, don't get me wrong.
He's married, so no chances to become his wife. );
Beryllium oxide is used as sockets for highpower tubes in ham radio amplifiers because they are very thermally conductive. As long as a file or other means does not create dust that could be breathed in its considered safe.
Great , Thanks for very valued information , Allso your Explains in deed Great Excellent , Keep going All the best good luck
Ok my second time back here after thinking about that copper arrangement in the middle - which is why I'm on your page bro.
I'm holding one and haven't scratched it to see it's copper yet - and because shit happens I just wanted to know what was in side. Now I'm glad you are here because I was going to cut the other end off first and I would have found the "boring light bulb" bit and missed out on the "Antenna"
Now back to the 2.45 GHz and that copper top bit you ripped off.
Suggested observation
A. there is a ring capacitor - you can't get away from those two rings and Cap's everything down to that gap which means it's an "Antenna"!
B. How those chambers work is going to be the magnet flows. [has to be look at the flow]
This is working in the same way you can drop an iron bar in acid and paint copper direct on to it using Amps / Volts and the medium is the acid.
Here the Medium is the stressed Magnetic Field - the distance of those magnets and going to be right on a stress point and those copper shapes give it exactly what it wants to effect electrons [just like an Air coil ] without iron.
Look at it, Everything between the magnets is copper or alli and of those "Copper controls Magnets" and therefore the alli is to control backfeed - collectors or reflectors .
So they're compressing microwaves into they 14mm x 12mm wide copper stub under the top then out through that 5mm hole at the top.
When you have a look at the fine edge of that 14mm stub in the middle on the fine edge in the 5mm part under the hole in the cap, you can see the copper has been stolen - !IT'S MOVED SOME COPPER! using a magnet and pressure and the 2.45 is as you say only water related.
Right! I need to cut the end you did off first - Thanks.
Have you got an operating Tesla Coil - and Air Coil where a base frequency sets off a simple "child on a swing" effect controlled by a single power supply and a crude capacitor and spark?
The medium there is air and the magnets are replaced with frequency.
How may times do you push that child and right time per second .
When you go Too High the Tesla Coil will begin to spark from the cap.
"STATIC" is Achieved just BEFORE the spark at the cap of the coil.
STATIC - is a very fluid state where MATTER can be influenced by magnetic.
Hand's up anyone who can tell me where the Largest Working Tesla Coil in The World is?
Speak up anyone who can now name the Largest Twin Tower Tesla Coil ever constructed?
Very informative video...well done bro
Love your accent 🥰🥰🥰 ... just make me melted down
Z té angličtiny slyším samou češtinu, je to tak? :-D Jinak super video, neměl jsem nikdy odvahu zrovna tohle rozebírat
i love watching your videos..
Thank you for this very interesting video
Btw. the radiation isn't generated by electrons hitting the anode. The electrons circle the cathode passing by the cavities. This creates a resonant electric field which in turn influences the electrons so they bunch up while circling, increasing the resonance amplitude further. A part of that is tapped of by the antenna. Electrons only hit the anode if they lost too much kinetic energy.