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 UA-cam (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
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...
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)
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.
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.
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.
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.
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. 🤯
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.
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.
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.
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 :)
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. 🙄
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
@@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 watched the whole video just to hear more of his pronunciation :-) 5:44 "here is the ferayt coOoOorrrr" 6:48 "brasss wayyrrRrrRrrrr"... marvelous, subscribed! :-)
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
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.
ok, great. a magnetron seems to be a compareably solid build, so why did i had to replace one in my oven the other day? what part of it might fail? there seems nothing to be moving in there, can it overheat?
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. ua-cam.com/video/5tTkDQnT95g/v-deo.htmlsi=5rD8KGjWz7vy54zU ua-cam.com/video/zKTS95KOrOI/v-deo.htmlsi=ncN-2HCduKM4PDLk .ua-cam.com/video/E18iLLioN6o/v-deo.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.
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!
I don’t have any background with vacuum tubes but the specification that stands out to my mind is the low voltage/high current of the heater. Is there a particular reason for this?
It's easier to make a low voltage high current filament. It's short and thick. A high voltage low current filament would be very long, thin and fragile. Just take a look at 230V 10W lamps. The filament breaks just from a wry glance. And also the transformer winding is easier to make for a low voltage. And finally, in a directly heated vacuum tube, the filament current must be many times higher that the emission current, so that the emission current doesn't change the temperature of the cathode much. In other directly heated vacuum tubes (amplifiers), the filament voltage also intereferences with the signal, so it also has to be low for this reason.
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.
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. }:)
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
At first I thought you sound funny but as I listened and watched other videos explaining the exact same things you were saying I knew you know what your talking about
Just remove the magnets. The magnetic induced spinning electric field is what causes the oscillation. Remove the spinning part and it operates just like a diode.
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!
You seen to be a very intelligent person. Do you mind answering what's your formation? I'm getting my electrical technician degree soon, but i'm not even close to knowing the things you know.
It's actually connected to 5 of the vanes by virtue of the copper ring that joins them all up, the diameter of that ring is probably optimised to be resonant at 2.4ghz, or to connect them all up at a node of some sort, to extract the energy from all 5. As Diode says, stuff at RF frequencies is pretty much witchcraft and nothing is what it at first glance appears to be.
@@Tekwyzard by taking the fact that at that high frequency every tiny metal with act as inductor and and slightly changed distance of electrical contact will also matter seriously , so its confusing to see that ring are at the edge of inside and only one antenna are connected with one lc tank which is fare from ring area !! Their seems multiple lc tank in that copper circuit so why only one can radiate for getting its full power then from all ?
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!
Newbie here, and I know it's old ... but how is the pulse sent out? How is the pulse sent out at 2.45 GHz? Is it the size of the cavity or the frequency? Does the anode "push" it out? Some many questions ...
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 UA-cam (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
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*
This is the most interesting explanation (and teardown as well) I've ever met on this topic.
Big thanks!
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.
My head is swirling just as the electrons inside the magnetron! Great video!
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
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)
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.
Amazing job, thank you. For the first time ever, I have an intuitive feel for how the magnetron works, with some great insights.
Noticed it is RARE to read SO MANY positive comments regarding someone explaining electrical things on UA-cam.... Well done
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!
This is the best, most comprehensive and complete explanation of a magnetron that I have seen, thank you. :-)
9:00 Man, your cat is more useful than most of the tools in my workshop.
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.
Enjoyed the video and your knowledge in Black Magic.
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.
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.
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. :-)
Who ever Designed the Magnetron is a Genius...
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.
Such a poetic and musical accent. I could listen to this man reading the telephone directory!
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. 🤯
19:08 36 uR/h, not great, not terrible!
I cut open one of these with a hacksaw by hand once. It took almost 5 hours to cut open fully
MagnetronGoneWild
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.
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.
this is it, here is the man who knows his work, pure explanation you the best🤙🤙
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.
A magnetron is quite facinating piece of alien technology even for me as an electrician.
Omg, what an unusual accent 😂! But this explanation is one of the best I have seen!❤
Full postmortem of Magnetron. Lots of info in this video. Thank you very much.
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.
- 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
Top Explaind ! The Best in UA-cam so far.
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. 🙄
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
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
Thank you for debunking the Beryllium Oxide myth. It's like an urban legend that wouldn't just go away
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 "
This guy sounds like he's singling. Nice 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! :-)
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
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.
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?
Very good esplanation about inside Magnetron. Thank You Sir.
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...
ok, great. a magnetron seems to be a compareably solid build, so why did i had to replace one in my oven the other day? what part of it might fail? there seems nothing to be moving in there, can it overheat?
Muito bom
Best channel ever...
What if you increase its HT voltage , what affect will occur ??
Change frequency or just power ?
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.
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
Yet another nice video. Magnetrons are part of our lives but scary in various ways.
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.
ua-cam.com/video/5tTkDQnT95g/v-deo.htmlsi=5rD8KGjWz7vy54zU
ua-cam.com/video/zKTS95KOrOI/v-deo.htmlsi=ncN-2HCduKM4PDLk
.ua-cam.com/video/E18iLLioN6o/v-deo.htmlsi=RyRc6nrJXrIbcAAt
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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.
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!
Awesome vid bud. I really like these. Do u have a doctorate in the electronic field ? Your knowledge is far beyond many.
I don’t have any background with vacuum tubes but the specification that stands out to my mind is the low voltage/high current of the heater. Is there a particular reason for this?
It's easier to make a low voltage high current filament. It's short and thick. A high voltage low current filament would be very long, thin and fragile. Just take a look at 230V 10W lamps. The filament breaks just from a wry glance. And also the transformer winding is easier to make for a low voltage. And finally, in a directly heated vacuum tube, the filament current must be many times higher that the emission current, so that the emission current doesn't change the temperature of the cathode much. In other directly heated vacuum tubes (amplifiers), the filament voltage also intereferences with the signal, so it also has to be low for this reason.
@@DiodeGoneWild awesome explanation, thank you!
@@DiodeGoneWild Thanks very much for this, makes sense
@@DiodeGoneWild you the man
Good work brother
very good. nothing like taking something apart to better understand how it works.
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.
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?
I love your lessons! You are in absolute the most interesting you-tuber in this charming subjects!
Don't you ever try to die! Who am I going to watch during breakfast? :-)
Happy Thanksgiving from Texas!
Stay safe...as you can LOL
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....
You are an excellent teacher!
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
does the antenna output also generate radio frequency or high frequency alternating current?
Z té angličtiny slyším samou češtinu, je to tak? :-D Jinak super video, neměl jsem nikdy odvahu zrovna tohle rozebírat
At first I thought you sound funny but as I listened and watched other videos explaining the exact same things you were saying I knew you know what your talking about
i learn a lot from you and you make it very easy , thank you .
Thank you for detailed knowledge. I just sliced one of my magnetron just to see inside. Should i throw out cathode ? If its radioactive.
Pokud je anoda na potenciálu uzemnění, co se stane v případě přerušení PE vodiče? Bude na kovovém těle mikrovlnné trouby NDN?
I heard somewhere that you can take a magnetron apart and remove the tube and magnets and use it as a high voltage diode. Is this true?
Just remove the magnets. The magnetic induced spinning electric field is what causes the oscillation. Remove the spinning part and it operates just like a diode.
oh ok. thanks for the explanation!
without magnets can you use it as a triode?
@Crash Nebula
there are only two terminals (heater-cathode and case-anode) , so a diode maybe :-)
@@YTANDY100 hahaha! a triode IS! a diode with hot katod ..... accipicchia
@@-Crash-Nebula--
triode is a tube with 1 grid :-)
the heater doesnt count unless it is the cathode :-)
Amazing...almost as mind blowing as trying to understand the universe!
Can this be use to make a crude electron smasher
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!
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. );
starei ore ed ore ad ascoltarti!
First time watching this channel....
WOW, what an accent!
very nice autopsy and physic explanation thank you ..your Name?? i am a radio amateur passionate of electronic since 40 years
Ngl your accent is funny AF😂
they do have parkside in india?
You seen to be a very intelligent person. Do you mind answering what's your formation? I'm getting my electrical technician degree soon, but i'm not even close to knowing the things you know.
Flow of electron it mean arc inside magnetron?
11:12 why antna are connected with only one out of 10 slot instead of connecting with all to get power from all ?
It's actually connected to 5 of the vanes by virtue of the copper ring that joins them all up, the diameter of that ring is probably optimised to be resonant at 2.4ghz, or to connect them all up at a node of some sort, to extract the energy from all 5. As Diode says, stuff at RF frequencies is pretty much witchcraft and nothing is what it at first glance appears to be.
@@Tekwyzard by taking the fact that at that high frequency every tiny metal with act as inductor and and slightly changed distance of electrical contact will also matter seriously , so its confusing to see that ring are at the edge of inside and only one antenna are connected with one lc tank which is fare from ring area !! Their seems multiple lc tank in that copper circuit so why only one can radiate for getting its full power then from all ?
The total frequency is coming from the one antenna you don’t need more.
A good explanation, very interesting, thank you.
what's the point of using a radioactive metal for the coil?
Are those your plumbing tools?
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!
im a fan of your cat :) i was wondering if this was where the magnet was your vid helped now i want the magnets :D for an art project
I really appreciate watching your videos and I like to learn from your channel
Great explanation and loved your diy GM counters too!
Newbie here, and I know it's old ... but how is the pulse sent out? How is the pulse sent out at 2.45 GHz? Is it the size of the cavity or the frequency? Does the anode "push" it out? Some many questions ...
hello LEDgW, how long are the insulator, I mean could we cut closer to the antenna ? (less material to cut to get the copper :))