The Device that Won WW2 - The Cavity Magnetron
Vložit
- čas přidán 26. 08. 2023
- Get NordVPN’s 2 year plan + four months extra for free here: nordvpn.com/curiousdroid It's risk-free with Nord's 30-day money-back guarantee!
It's said that the atomic bomb ended WW2 but the Cavity Magnetron won the war. The invention of this palm-sized device gave first the British and then the Americans a microwave radar generator that was 1000 times more powerful than anything they had before and enabled small high power radar to be fitted to planes, ships, and vehicles. This transformed the war and swung it for the allies in Europe and the US in the pacific. This is the story of the Cavity Magnetron.
To give one off tips and donations please use the following :
www.buymeacoffee.com/curiousd...
or paypal.me/curiousdroid
This video is sponsored by nordvpn.com/curiousdroid
Written, Researched and Presented by Paul Shillito
Images and footage: Images and footage : US DoD, US Navy, Raytheon, MIT,
And as always a big thank you also goes out to all our Patreons :-)
Eριχθόνιος JL
Adriaan_von_Grobbe
Alex K
Alipasha Sadri
Andrew Gaess
Andrew Smith
Brian Kelly
Carl Soderstrom
Charles Thacker
Collin Copfer
Daniel Armer
erik ahrsjo
Florian Müller
George Bishop II
Glenn Dickinson
inunotaisho
Jesse Postier
Joey Piccola
John & Becki Johnston
Jonathan Travers
Ken Schwarz
L D
László Antal
Lorne Diebel
Mark Heslop
Matti J Malkia
Patrick M Brennan
Paul Freed
Paul Shutler
Peter Engrav
Robert Sanges
Ryan Emmenegger
SHAMIR
Stefan Hufenbach
Steve Ehrmann
Steve J - LakeCountySpacePort
tesaft
Tim Alberstein
Tyron Muenzer
Will Lowe - Věda a technologie
Get NordVPN’s 2 year plan + four months extra for free here: nordvpn.com/curiousdroid It's risk-free with Nord's 30-day money-back guarantee!
It was the Soviet army that defeated the Nazis - ask the German historians.
It was the Soviet army that liberated the concentration camps in Germany - ask the Jews and other prisoners freed from these evil monstrosities.
The terrorist war atrocity nukings of civilian centres in Japan did not end the war.
Remember, the Soviet Union lost over 25 million people in WW2. The USA lost less than 400,000 and the UK less than 600,000.
There were lots of sacrifices made by many nations but lets not engage in historical revisionism and Hollywood myth.
There is no such thing as climate change. Please stick to the science and don't spew PROPAGANDA
ProtonVPN is way better, nordvpn is no good for Arrrrrrrrrrrrrr.
You switching between talking loudly and then going back to nearly whispering makes it hard to follow the video.
thank goodness that thing helped win the war. It would’ve been horrible if Europe would’ve remainded European. London would still be English. One shudders to imagine the horror
I started working at Raytheon in 1967 at the old Microwave & Power Tube plant in Waltham Ma. Percy had retired by that time but he still maintained a lab at his home in Newton Ma and would call my boss for parts he needed for experiments. I used to drop them off on my way home. He was an interesting guy. The plant was full of old WW2 & Korean War tube production equipment which we occasionally had to get up and running so we could produce replacment tubes for equipment still in use. It was an "electronics museum". There were some areas which were just as they were in 1945 until Raytheon went out of the microwave tube business in abt 1993. I stayed with Raytheon until I retired in 2010 and could be the "last link" to Percy at Raytheon.
That is a great story. Thanks for sharing.
Yeah great addl background, I play guitar and Tubes are still the best organic tone, so sorry the US lost all this special stuff..
we designed and manufactured microwave tubes; magnetrons, cross field amps, klystrons, TWTs at Microwave & Power Tube in Waltham Ma Raytheon was in the comsumer tube business in the "early days" but that was long over when I got there in 1967. I designed factory test equipment for the Tube Group. There was an attempt to make microwave oven tubes there but that failed because that was a different "culture" from miltary contracts and we couldn't compete with the off shore manufacturers. I will only use tubes in my high power Ham station amplifers, 73 Mike, K1FNX @@skeeterbodeen8326
I asked Percy about this and he said he never met you
QSL, it's been a long time and I'm sure his memory isn't what it used to be @@user540000
A part of this story I found enlightening was that the US manufacturing engineers changed their manufacturing from a high precision milling operation to a metal stamping job. They stacked metal disks to build the magnetron instead. This meant they could be built in the thousands by machine operators and assemblers instead of a master machinist.
That was the 'magic sauce' for mass production. I've taken apart modern heating type magnetrons and they don't look precision. Would love to know if that is just due to the lack of need for a precise output frequency, or just design improvements.
@@clytle374 the magnetron in microwave ovens don’t need a narrow frequency spectrum. They’re not measuring return pulse time, just jostling water molecules.
Yup, I learned that from Bill Hamac's recent video (Engineerinf Guy)
@@norlockv They oscillate at the resonant frequency of water. This is what jostles the water molecules.
Very sorry, what I read was wrong, so I was wrong. Here is the correct information:
Quote: A study of a typical household microwave oven conducted by Michal Soltysiak, Malgorzata Celuch, and Ulrich Erle, and published in IEEE's Microwave Symposium Digest, found that the oven's frequency spectrum contained several broad peaks that spanned from 2.40 to 2.50 GHz. Furthermore, they found that the location, shape, and even the number of broad peaks in the frequency spectrum depended on the orientation of the object that was in the oven being heated. In other words, the exact frequencies present in the electromagnetic waves that fill the oven depend on the details of the food itself. Clearly, the microwaves cannot be tuned in frequency to anything particular if the frequencies change every time you heat a different food. Unquote.
And the reason for the frequency, is so the FCC has that classified for microwave ovens.
Thanks to the more 'educated' responders in setting me straight. 🤒
@@David-yo5ws Nope, that's not what's going on, and not true.
Back in 1973, I failed in my attempt to dissuade a manager from heating a tin of soup in a full sized microwave oven. Observing from 10’ away, I saw a most surprising sight - a lovely noise and a nearly unhinged door. Not altogether a peaceful application.
Another excellent video, by the way.
Well if it was tomato soup, I am sure his face was redder. 😳
Put a tin of tomato sauce in a conventional oven and the same thing will happen.
Try a sausage without puncturing the casing. What a mess!
@@musicbruv Open fire will do it as well. Back in 1992 I saw a guy heat a can of chicken frikassé over a Hexamine solid fuel burner without opening it. Pretty amusing sight though when that thing popped open :D
Well, it was '73.
I always love small, solid objects that do something neat with physics just by the way they are shaped.
It's kind of Lovecraftian, actually. Lovecraft stories often feature geometric shapes that make people insane by looking at them or which channel energy and open portals to other dimensions.
Like Wacław Struszyński antena for:
"High-frequency direction finding, usually known by its abbreviation HF/DF or nickname huff-duff, is a type of radio direction finder (RDF) introduced in World War II. High frequency (HF) refers to a radio band that can effectively communicate over long distances; for example, between U-boats and their land-based headquarters. HF/DF was primarily used to catch enemy radios while they transmitted, although it was also used to locate friendly aircraft as a navigation aid.(...)
Land-based systems were used because there were severe technical problems operating on ships, mainly due to the effects of the superstructure on the wavefront of arriving radio signals. However, these problems were overcome under the technical leadership of the Polish engineer Wacław Struszyński, working at the Admiralty Signal Establishment. As ships were equipped, a complex measurement series was carried out to determine these effects, and cards were supplied to the operators to show the required corrections at various frequencies. By 1942, the availability of cathode ray tubes improved and was no longer a limit on the number of huff-duff sets that could be produced. At the same time, improved sets were introduced that included continuously motor-driven tuning, to scan the likely frequencies and sound an automatic alarm when any transmissions were detected. Operators could then rapidly fine-tune the signal before it disappeared. These sets were installed on convoy escorts, enabling them to get fixes on U-boats transmitting from over the horizon, beyond the range of radar. This allowed hunter-killer ships and aircraft to be dispatched at high speed in the direction of the U-boat, which could be located by radar if still on the surface or ASDIC if submerged."
From August 1944, Germany was working on the Kurier system, which would transmit an entire kurzsignale in a burst not longer than 454 milliseconds, too short to be located, or intercepted for decryption, but the system had not become operational by the end of the war.
It's so cool, stuff like HAARP is jsut a bunch of wires arranged In a certain way that if you put power threw the wires in the right frequency you can heat up the ionosphere
And their shape gives them funny 'adopted' names. Like the early curved RADAR structures being called a 'Dish'. And a big rectangular rotating structure was called the 'bedstead'.
Circular shapes are the most efficient that's why they are used, they are not solid first, and the amounts of space inside can be magnified by various methods, look into night vision scopes for example
I worked with a British Engineer that worked on the magnetron. I met him at the end of his career in the 80s. He was proud of what they had accomplished.
Was he cute?
@@retiredbore378 My dad worked for IH and my Granpa Deere they had some interesting breakfast conversations over the years. My dad was part of the team that invented the hillside combine and 2+2 tractor, I don't know if it was just him or a big team. Glad you are enjoying retirement.
@@Hugh-Janus69420 no
As he should!
My grandfather worked on the magnetron project during the war. He told us that he dropped the first prototype and broke it lol. His name was John Linsley-Hood.
I imagine the creators would go something like
"Magnetrons!! There's literally a billion of these in use in the future"
> "Oh no the war didn't go well?!?"
"Oh no it went really well. They are used in the kitchen."
> "WHY DO PEOPLE NEED TO RANGE FIND LARGE METAL OBJECTS IN THEIR KITCHEN?!"
I have a Husqvarna microwave oven from 80´s in my kitchen, and still works reliably. Made in U.S.A.
I love how there is no end to "the ____ that won WWII" video possibilities. They always end up being fascinating. They pretty much let the world's engineers go buck wild for a whole decade.
It would have been great if it were under different circumstances where we all weren't trying to kill each other.
I get what you are saying though. War time usually leads to technological advances.
That's the only good thing that comes from war. Rapidly accelerated technology development. Right for the wrong reason.
The relevance is important.
Well then,
yer simply gonna be ecstatic
to see what single handedly
won World War Three!
@@slugface322 we all know it's AI already
I'm pleased to see Sir Mark Oliphant get a mention. He was the quiet Aussie who always got on with things pushing for more to be done.
Atom Bombs was one of the other things he was involved in , the man who most likely kicked off the Manhattan project when he sat in on one of the US Uranium Committee meetings and asked, Haven't you guys read the MAUD report???.
Less the Elephant in the room. More of an Oliphant in the Laboratory. Yes, I keep pachyderm puns in! A mammoth tusk indeed.
Another unrecognised Australian.
Not in his home state, South Australia. Knighted in 1959 Sir Mark Oliphant became Governor of SA in 1971 @@Skipper.17
Wish people would listen to interview with Mark Oliphant
Factoid about that early British research is that they needed to dump all that microwave energy during testing, and did not want to radiate it out. So they buried a lossy coaxial cable into a nearby salt marsh, where the late night testing caused unusual heating of the salt marsh, and a fog bank that was only over the dummy load area.
Lol you said load
A lossy RF cable is a brilliant way to transfer the RF energy into thermal energy. High power RF attenuators would surely be rare and expensive in those days.
thats interesting
@ProfSimonHolland i also found their statement to be interesting.. Especially the part where they said, "Load"... 😄
@@Hugh-Janus69420 quite revealing
Great video! It should be noted that after the war, Yoji Ito, who co-developed a 8 segment 30cm cavity magnetron in Japan back in 1938, and then a 24 segment 10cm cavity magnetron in 1939, was shocked when saw the Birmingham magnetron in a museum in the UK as it had a shocking resemblance to his own design, in a fascinating case of convergent design.
-The Japanese Yoji Ito and colleagues) (invented a multi-cavity magnetron with circular cavities and narrow slits about 1 year before the British (Randal and Boot) and also developed strapping. They made and operated several 10cm radars by 1942. They started with magnetrons with square cavities and refined the process of understanding. The Germans Sanitas Company had a 2kW 22cm multi-cavity magnetron by 1939. There is a nice paper by "Doering" on German microwave tube development (costs about $25) which has a picture of a German magnetron with circular cavities and narrow slits by the company Lorentz. It was only small device.
-The Germans did have a microwave program. One targeted 25cm wavelengths using the LD6 and LD7 disk triode which could produced about 30kW - 50kW pulses. This device could produced coherent pulses for use in Doppler radar. The other targeted 5cm using a tunable split anode magneto of about 1kW.
-In 1942 the Germans decided they didn't have the resources to develop microwave radar and that their existing radars were adaquet and so the program was disbanded with many of the engineers and technicians going to the Army. When the British H2S CV64 Magnetron was recovered at the end of 1942 the experts had to be brought back together.
LD6 and LD7 development continued because of the 27cm FuMO 231 Euklid fire control radar for the German Navy. The LD6 could produce a 16kW pulse at 9cm so it was competitive with the first generation of British H2S magnetrons but with the advantage of being coherent. .
@williamzk9083 Wow! This response contained more detailed information than the video. Thank you!
Magnetrons are also used to generate x-rays to treat cancer. The gold standard is klystron, but magnetrons are also widely used due to their smaller size.
I had to go look this up. Magnetrons operated at extra high voltages do generate electrons that generate "breaking radiation".
@@jamallabarge2665 As I said, magnetrons are still widely used today, in new treatment machines. Typical energy of the resulting xrays is about 5 MeV.
@@jamallabarge2665 Was just going to say it would have to make use of bremsstrahlung.
This was a great video, I thoroughly enjoyed it. I worked on Radiotherapy machines for many years. The magnetron is used to generate high power microwave RF (travelling wave) within a tuned linear accelerator (Linac) structure. Note that the RF is used simply to accelerate electrons, so does not generate X-rays directly (at least not on medical Linacs that I know of). Electrons from an electron gun are injected into the linear accelerator at the point where the RF enters the linear accelerating structure. The electrons are initially bunched into packets and "surf ride" the RF wave, accelerating to near light speed, gaining 7x their rest mass in the process. Near the far end of the accelerator, any unused RF is recycled and sent back to the input, or dumped if not required. However, the accelerated electrons continue on their accelerated trajectory. The accelerated electrons then pass through a bending magnet (narrow band energy filter). The bending magnet does not allow electrons that are too low, or too high in energy to pass through. Only those electrons that make it through the bending magnet are at the desired energy for clinical treatment. They then collide with a water cooled tungsten target. These collision cause electrons in the tungsten atoms to jump to higher orbits, then drop back down again, giving off excess energy in the form of a photon in the X-ray spectrum. Final note: You can also have Linac that uses a standing RF wave, rather than a travelling wave.
Great video here for anyone that is interested. I used to work on these machines. czcams.com/video/jSgnWfbEx1A/video.html
according to CZcams every device from WW2 won it
I thought it was the enigma code breaker alan turin ' but your right ' the say eveything won it ' i suppose we all played a huge part ' ie soldiers ' their only remembered with a gravestone' & not a knighthood 🤔
I change magnetrons fairly frequently. They are used for producing microwaves inside Semiconductor Ashing machines where silicon wafers are cleaned using a basic O2/N2 microwave plasma. This is usually part of the Dry Etch process. This is however only cleaning. More aggressive etch processes use other gasses and RF generators to produce the plasmas. This microwave plasma is typically pink in colour. It’s actually quite a hard plasma to ignite ( hence when the magnatron isn’t working 100%, it needs replaced.)
No clue what you just said but wafers are cool. I eat them sometimes. With cream cheese. Or regular cheese. I like cheese too.
@@davidtatum8682 LOL! Semiconductor wafers is also safe to consume with cheese!
@@manishsakariya4595 good to know. I'll try it.
@@manishsakariya4595but they are really crunchy....
I used to do epitaxial growth on indium phosphide wafers and now I change magnetrons in people's microwaves for a living, among other things. Turns out randos who want their kitchen fixed pay more than fortune 500 companies that require you to hand pour HF for a wet etch process. Go figure.
Sir Mark Oliphant was from Adelaide in South Australia, and after his retirement from a science career, he was appointed as Governor of South Australia.
One of the first books I ever got into reading was a huge book published in the early 50s called Principles of Radar. This was the bible of radar technology from that era. My father used to work in the military designing this kind of thing. It was full of calculus. Fortunately I found a second book in the loft on calculus, so realised I needed to learn that first. I knew what a klystron and a magnetron was at the age of 12!
By Merrill Skolnik, perhaps? Maybe not. I think his book was called _The Radar Handbook_.
Fort Bliss ?
@@finddeniro Ultra Electronics in London
One thing that people don't mention is the Cathode design in the GEC Magnetron wasn't designed by them, it was French!!! One of the French electronics research labs near Paris shared the design of that cathode with GEC in May 1940, just before the Germans Invaded. What it did do was massively extend the running life of the device and allow very high power, especially when GEC discovered that to stop the cathode from burning out, as soon as you had the magnetron run up, you had to turn the heating element off, as a sizable amount of electrons were being thrown back into the Cathode by the magnetic field and they caused it to heat up,
yes....this is a fascinating story
That was done by Maurice Ponte. When the Germans invaded France he went to Britain and gave his information.
Dutchman Klaas Posthumus who worked for Philips did research and wrote theoretical articles before the war and so helped Randal and Boot of Birmingham University with their thinking.
In the sixties, my brother and I played around with war surplus magnetrons. He went on to designing and building electronic control devices. I went on to designing and building musical instruments. Whatever.
Fascinating history, physics, and technology. Thanks again from cloudy Vienna, where lunch is always on me if you're in town, Scott
I was a kid in those days too and a bit of a mad professor. I remember we could buy X-ray tubes from advert's in electronics magazines and electronics surplus stores. Soooo dangerous, luckily I wasn't interested in them.
Do you both have cataracts now?
@@OoooooooLongJohnson No cataracts, but I do need reading glasses.
Mark Oliphant, an Australian, also discovered tritium and many other things. He went on to contribute valuably to the Manhattan Project, but regretted his involvement and was an avowed pacifist and humanist. He was a close friend of my wife's family in Canberra (where he was pivotal in establishing the Australian National University) and I saw him a number of times at family lunches. He was a guest at our wedding in '97. His life story is fascinating and worth reading about. I'm still in touch with his grandson - we catch up every few months.
I worked with an old WW2 radar tech, many years ago. He told me that when they brought it over, it blew his mind as to what that thing could do. Very interesting fellow to talk to. Passed away some years ago.
Never ceases to amaze how much of our modern world was created during/because of WW2.
yeah, and how much of it is going to be destroyed by the next one…
@@marklewus5468You sound like fun!
they say war brings death... the unsung part of war also brings lots of technology research money grants. Because there's no better way to innovate technologies than to simply propose to a prospective government the possibility for a fancier stick and rocks to kill the other with. Albeit something that can be resolved culturally and not hardwired into us. \o/
Then you should be even more amazed by what was developed during the race to space - Gemini, Apollo, etc.
Nobody notices millions of inventions during peacetime, but they're just as important. Nobody notices all the inventions that weren't created, because the war effort sucked up all the money and resources.
There are several interesting strands of this story that could be expanded into more detail. The early development in several countries was most interesting. So was the sea-going anti-submarine war with a host of other technological tools & weapons. Then the H2S development path & policy for it's use. Some remember "The Secret War" series, with the battle of the beams etc. I'd love to see more done with these subjects.
People I used to travel with every day in the 70s & 80s had been fighting in WW2 in tanks & aircraft. They wanted to read all about the technology that saved Britain when they were young. But most was still secret. I wish they had known then what I know now, but most are long gone.
"The Secret War" 😍😍
The Secret War is awesome. 1970s documentary featuring a lot of interviewees from both the UK and German side about WWII high tech. I had to go to Daily Motion to find the episodes, I think CZcams takes them down.
@@RCAvhstape I've watched all of them. 😁
My dad (Okinawa) gave me Winterbottom's book on the code war not too long after it was published in paperback.
#funfact Sir Mark Oliphant was a former Governor of South Australia. He presented me with an award I won when I was in Scouts way back when. A nice guy from my fading memories. He should have been mentioned in the recent film Oppenheimer but as he wasn't American - he wasn't.
Thank you for covering this, my late father was involved in the Goonhilly project but had been interested in radio from childhood. I do remember him trying to explain cavity magnetrons to me at a very early age. Little did I know then that I would be later working in a GEC laboratory adjacent to Hirst Research Centre in Wembley. Later on I worked for Racal BCC, I remember sitting in their reception awaiting my interview and picking up a copy of RF Design that included a hobbyist design of an FM television transmitter based on the magnetron from a microwave oven. By modulating the current through the magnetron as though you were attempting to create AM with limited modulation depth it generated an FM signal with many megahertz of deviation.
The video has reminded me that I actually own a WW2 Radar test set which I intend to pass on to the Radar Museum at Neatishead, near where I now live. I feel I grew up in the most exciting time for electronics, though I may never use my stock of WW2 807s.
My 2 way radio work often took me to Bawdsey, a significant site in our radar history.
We still use magnetrons and klystrons today on certain ghz communication equipment. One example is the an/trc-170 used by the Marine Corps.
In 1980 at the RIMPAC exercise's, our 'old tech' ship was in Pearl Harbor and I got the chance to go on a shakedown of an advanced US satellite ship. In their RADAR room, they had this high tech klystron. I said "What do you do when you want to change the klystron frequency?" The Radio Engineer said "We just turn this switch here. We can change up to 12 frequencies and set it to change every rotation too." I said, "Well we have to pull out the spare one from it's wooden box, swap it out with the operating one. Then we have to get a book out and run it through the coarse tuning by turning a wheel and watching a dial, then fine tuning. That takes us about 10 minutes at best speed." It was a real credit to American advancement. However, on exercise, we had an old low frequency RADAR, that we were not allowed to use, because the Americans could not jam it. So, we snuck in an occasional 1 scan. They would be able to pick-up we used it, but of course we could not 'confirm or deny' it was operating. Fun and games is great in peace time.
I bought my first microwave in 1975, an Amana Radar Range. I still have it in storage. I may have to dig it out and see if it still works. It weighs about 3 times as much as the one i bought last year for the kitchen rework. Cost $425 on sale back then, I don't know how I afforded it. Another great video!
The copper in it might be worth about US$80.00 if you were willing to strip it down. But I think if you put a fish tank inside it (don't turn it on 😉) it might make it a great talking point about the ol' Amana.
My Mother bought an Amana Fridge / Freezer about 40 years ago ** from a London department store which is still in use today (she's 98) here in the UK.
A Thermador microwave oven came with it free of charge ! It had no turntable but instead had a slowly rotating `stirrer' mounted in the roof I assume to scatter the energy. There was a rudimentary grill IIRC.
** The technician who used to look after it said they no longer last like this one, advising he had to replace a compressor after only 6 years of service recently (this is about 10 years ago). May be due to the new green refridgerants ? or they just decided they were lasting too long.
Amana was the brand name used by Raytheon for the microwave ovens.
Does it have one large dial on it ?
I worked in satellite communications in the 90's and an interesting aspect of the klystron tubes is they were tunable. The resonant cavities that sat along side the electron beam had small plungers connected to screw mechanisms. This allowed the plungers to be moved and change the size (and therefore the resonance) of the cavities. We had a procedure to change the tune of a klystron; first we would unlock the tuning mechanism, then change the tuning, then re-lock the mechanism.
Another advantage of the klystron is that you can tune the cavities to a single frequency and get LOTS of gain in a narrow frequency OR stagger tune them for increased bandwidth at the cost of gain.
Klystrons, however, are not used much in radars today because mechanical tuning does not lend itself to rapid electronic tuning.
Very interesting video, Paul. Always fun to learn about the components and tech that give us the conveniences we enjoy. Nice shirt, too. Hope the cancer recovery is going well.
Actually the random phase of magnetrons is a feature. In a sense it tags each pulse with extra information. Some klystron weather radars introduce quasi random phases to emulate this "flaw".
King 🤴 klystron 🙏
Essentially that's the earliest example of spread spectrum transmission, even if that was never the intent.
FM lonlinear modulation.
Great video! I'm a radio enthusiast and I thought I knew most of the history behind the magnetron, but you managed to fill in a few gaps I didn't know I had.
What an absolutely fantastic video.
As per usual, this channel has stoked my curiosity, and made me more appreciative of the conveniences that surround me.
Keep it up!!
I see this guy every few years, he presents impressive informative videos that make me deep dive information I thought I already knew about. 10/10. I look forward to seeing you in like 3 years again mate
Great video Paul I always look forward to your new material.
The "Klystron" was so impressive at the time, even well into the 1950s when the movie "Forbidden Planet" was made. Commander Adams of the spaceship referred to the Klystron monitors so many times in the movie, it was predicted that the device would still be relevant in the future, hundreds of years from when the movie was made. Just an observation.
I love how this video ends with the technology used in something we can all relate to and use every day, showing just how much impact it had.
One of the early microwave ovens used in the home was accurately named the "Radar Range" made by Amana.
British technicians long knew of the warming effect of microwaves. They often would warm their lunch by leaving it near the magnetrons.
Thank you so much, really appreciate the vast amount of research put in to this 'episode'. Has answered so many questions I had, and a whole lot more I had not even thought to ask.
Our first oven was a 1975 Litton Minutemaster. 13 amps. Model 416. The box still holds christmas decorations to this day because they were generous with the cardboard..
Very interesting and very well done, as always, thank You Paul.
I never mind waiting as long as it takes for the next Curious Droid video to be made. They’re always great stories, well researched, well written and clearly presented for people who know a bit of science. Thank you. Your hard work is very much appreciated.
Worked on military and instrumentation radars for years in the MOD. Saw all sizes of Magnetron from little Decca boat radar mags to massive Long Range air defence mags that had a 2.2Mw pulsed power and were liquid cooled ! Our big radar was given a half hour warm up period, and I was always surprised how you could put a curry in the microwave and zap it straight away.
The candy bar story is bogus, because if there was enough energy to melt the candy bar while he was working on/walking near the transmitter, there would most certainly and unavoidably be enough energy to very quickly and quite permanently cook the eyes, *and* make him jump from large area superheating of tissue(not-quite-burns) before the huge thermal mass of the candy bar would allow it to melt. It's probably just the heat of it being in his pocket that did that.
This is also mostly why modern home microwave ovens have interlocks and shielding - their primary function is to prevent you from blinding yourself, followed by avoiding subsurface burns, and only in the last priority to avoid radio interference.
You know what newton ring are and why microwave cooker need to rotate🥱 Doubt you know
@@kwestionariusz1 Standing waves have no relation to why this story is bunk.
Fascinating how the UK's technological 'Crown Jewels' were bargained for orange juice and nylons (being cynical) - but lead to much of the modern world we now live in. Hard to imagine such gifts being offered effectively 'for free' today. But wars are the mother of necessity in invention when it comes to survival.
What rightly angers many Brits is with how much we "gave" to the Americans to ensure victory in the war, we were still demanded to pay back all the war loans while Germany got debts forgiven and even assistance rebuilding to the country it is now.
The Americans took advantage and then tried for the next 70+ years to claim they were the sole reason Germany didn't win the war.
@@Reinforce_Zwei Why do you think the Americans took so long to enter the war? it wasn't isolationism, they wanted the rest of the world on its knees so they could come in and take over. A state secret that will be kept classified for centuries.
In return, the US destroyed the German wolfpacks, ensuring delivery of lend-lease aid, and manufactured useable radar at industrial scale for use by Britain. I'd call that a fair trade.
@@Reinforce_Zwei The US could have stayed home and sat out the European war instead.
@@Reinforce_Zwei Brits paid only 10% of the value of Lend-Lease program and finished doing it after 50 years...
As a Polish i can say that our inventions that came to Britain and saved British are not even mentioned by British or they are even blatantly reclaimed as British invention.
Preaty sure no one knows: about Wacław Struszyński Huff-Duff antena(or its importance)...
Or even Marian Rejewski, Jerzy Różycki and Henryk Zygalski work and how they made working copy of Enigma and first devices able to find daily keys for it and how all that know-how ended up in Britain...
Any idea who invented hand held mine detectors used by alies in wwII?
As an early show of British gratitude Polish soldiers were not even invited to 1945 London victory parade...
Poland was sold to stalin and he took all reparations for Poland from Germany and not allowed Poland to be part of Marshall Plan, that btw you were happy to remove from your story as it provided a loot to post war Britain aka would contradict your biased story...
Only Polish soldiers were fighting in september 1939 and when Adolf was makind the decision to end himself only Polish and soviet soldiers were fighting in Berlin(and in 1939 soviet soldiers were fighting on axis side...).
I am also preatty sure that German logistics was destroyed by Polish Home Army in decisive moment of wwII(German forces about to conquer Moscow) not by British and British ofc repeating the fake "Russian winter" story.
The more impressive usage of microwaves is done in a company near me. They build microwave-based Mining equipment to break down ores without the need of chemicals. Needs a lot of power though. Something between 50 kW up to 20 MW depending on the rig.
They once said the biggest one they had build was powerful enough to increase the temperature of the water supply line of the city by 80 degrees in 1,5 seconds. So you put cold water in and only like 1 step further you had the same stream but boiling. Thats impressive.
Fantastic episode, huge thanks for putting so much work work into your videos. And as a side note, please, never ever change your style of shirts, they are what got me hooked on your channel in the first place, analyzing the patterns and trying to find something similar myself! 😄 Maybe you could get a sponsorship out of it? 😉
Another great video. I joined the Royal Navy in 1964 and saw my first magnetron in 1965 and went on to work on various Naval Radars up util 1980. I still have an old broken one in my loft somewhere, must look for it!!
Wonderful video, thank you for posting. Not only did Bell Labs copy the magnetron and begin production, within 1 week of receiving that first cavity magnetron, Bell engineers boosted its power about tenfold. Robert Buderi has documented much of this arcane technological history a great book "Radar:The Invention That Changed the World" which is now in paperback.
I sometimes think that it's sad that nearly all of humanity's technological leaps come about due to conflict or war of some type.
Yes I thought that too What will be coming from Ruzzia, Ukraine war Drones have taken a large leap already
It's the power of competition at it's finest and most extreme, trying to do better than someone else when your life is on the line is a massive motivational factor for many developments.
@@leehotspur9679 It's sort of the other way around. The commodification of drones and commercial access to parts revolutionized the use of drones in warfare.
Great show. From El Paso Texas, very appreciative of your efforts resulting in great insights into the past.
A great video and research! You have a gift for taking technical subjects and reducing them into plain language.
Welcome back, mate. 👋 Love your channel. 🙏🏻
The content and production as always are 1st class 🙂
Thank you for your quick look at a complicated history. Appreciate the way you were able to bring some coherent history out of all the threads to this. 😊
My father was a radio/radar technician in the RAF during the later years of, and post WW2. In 1948 or 49 he was bench servicing a night fighter radar system and almost, accidentally invented microwave ovens in a similar incident. He was pulsing the radar unit on the bench when he started to small smoke. He looked around and a tool rack across the workshop had caught fire from the tight beam of the radar unit. I suspect many who worked on them had similar incidents without appreciating the potential of their discoveries.
Wow! That was interesting ... so many things I didn't know in this story.
Paul, do you think you could do a video on the history and development of *torpedoes* ? I have always found them fascinating, but have never entirely understood how they worked, especially ww2 era devices.
Thank you!!
One of the first luxury use of the Microwave oven in the USA was in passenger trains. Thanks Paul.
One of the first microwave ovens used in the home was accurately named the "Radar Range" made by Amana.
My technical teacher in a Hungarian highschool told me that back in his early days he was working with plastic sheet welders which used microwaves as well. That time microwave oven was not even known to us. They used this for heating up coffees in lunch brakes :)
I want to know who convinced Doenitz that a 2000lb cow can't stomp on a mole hard enough to kill it...
Part of my work in USAF was tuning kystrons on our transmitters, as needed..
Thanks for not copywriting me, I use your videos to help educate students of science and I get excellent results because the people in my study group on Facebook all like the kind manners of the presenter plus his voice is so soothing I swear it helps my study buddies retain information easier.
Thank you so much for the work you put in to make these excellent productions, I'm extremely grateful for this kind of work.
🧠🤝✌
I agree - The pace and the tone of the presenter is superb
@@buddhistsympathizer1136 exactly. My users actually walk away with an education after I present this to them.
To be honest this production is so good it should be broadcasted as a TV show like on the BBC or on American, Australian and Canadian TV.
🇦🇺🤝🇺🇸✌
@@TheSunnyvaleTrailerParkAgreed but this and a small few other channels are too good for today's TV. To thrive there you need to be an idiot.
For the microwave radar receiver they needed a tunable local oscillator. This requirement led to the development of the reflex klystron called the Sutton tube after Robert Sutton who led the development. The Sutton tube was also vital for the development of microwave radar. It was also included in the Tizard expedition to the USA. There was a further development where they introduced a small amount of gas to ionise and protect the receiver during the powerful transmitter pulse. This was called the Soft Sutton Tube.
Excellent work as always Paul. A thoroughly enjoyable video!
The cavity magnetron wasn't the only high tech the Tizzard mission brought to the US...penicillin mold was also brought over and given to Eli Lilly and Smith Kline and French. Within 2 years they had developed methods to grow and purify the drug in bulk...saving many lives
MIT wasn't the only radiation lab set up. Georgia Tech set one up as well. It was still operational in 1968 when I started school there.
...I'm left wondering if the guys working on the magnetrons were cooking themselves then... which is not ideal.
Fantastic again, so many are not aware of how much this piece of history changed our lives.
you never disappoint, glad you are still healthy after the recent scare.
It melted his chocolate bar! What happened to his nuts?
It was a Mounds bar
Cuz
Almond joy has nuts
Mounds don't
Good video. I already knew some of this, but you put it together nicely. I learned a lot. Thanks, man.
Good stuff. The Germans used radar for their anti-aircraft batteries in France as early as the fall of 1941. For details google the Wurtzberg D. Commandos raided a site in occupied France in Feb 1942 and stole a copy. I think the location was Bruneval. Although a glorious chapter in British commando raids it is little known to war enthusiasts.
There was also the Dieppe raid, where part of the mission was to get info from the German radar site at Pourville, in August 1942. That was conducted largely by Canadians.
@@James_Knott Quite accurate James. The raid only partially succeeded, however. The attacking party of about 10 went up against a blockhouse fortified by machine guns at every window. The raid at Bruneval (Feb 42) alerted the Germans to the need to fortify radar installations near the coast, a fact which the Allies did not consider in planning Dieppe. The Dieppe raid was in planning for too long, had too many objectives in a complicated operational plan hundreds of pages long. I believe the raid at Dieppe was so convoluted as to hide its real purpose, to steal another radar set. The stated official objective, to see if Canadians could directly take a port city for a day, and then give it back simply does not make sense. In any case, radar was top secret so you wouldn't explain to the public why you planned a huge raid to steal a set at the cost of 5,000 Allied soldiers. At least they learned a few things, but in general Dieppe was a disaster. For the most part this cannot be put on Churchill's shoulders, it was Mountbatten that ran that shit-show from start to finish.
0:54 The magnetron? I nearly went for Miss Shilling's orifice until you read out the list.
A.C.Clarke's "Glide Path" is a great memoire of his time involved in this bit of WWII. Well worth finding a copy.
@@cancermcaids7688 I just preferred "Miss Shilling's Orifice" to "Mr. A. Hull's Cavity"! But whatever floats your boat mate! 😆
Watching footage of them experimenting with their old tech is so crazy. Something like an Arduino starter kit would've blown their minds. Just the mosfets inside were beyond their most high-tech capabilities.
It's not right to mock those that came before us. We stand on their shoulders (to borrow a quote from Sir Isaac Newton).
In a few years time our present day cutting edge stuff will feel the same... Primitive.
I remember how amazed we were in the early 1970's to see what a microwave oven can do.
The color television was almost as amazing in those years.
Would the inventors of the cavity magnetron have guessed that within a century, there would be a billion of them in every kitchen, and they'd be equipped with a clock that always seems to flash 12:00?
No, you're thinking about a VCR....🤨
I have never seen a kitchen with a billion cavity magnetrons in it. Perhaps the bigger catering companies might have such kitchens, who knows.
Fortunately mine has cancel which blanks out the clock. Just the timer displays. I have a real big clock, I don't need those tiny numbers to reset twice a year as well.
@@otpyrcralphpierre1742I realise I'm getting old when I see such technologies come and go.
Very good video. When you mentioned Bell Labs, the building shown was the Radiation Lab, or Building 19 at MIT. It was torn down awhile ago. Many researchers at MIT liked having their labs there because they were free to punch big holes in the walls and floors, as necessary.
Yes, and home of the Tech Model Railroad Club and the first hackers at MIT.
Love the WW2 content! ❤ Thank you
I love how they kept improving on the inventions
Just a question, what was Robert Watson-Watt doing in Britain while all this was going on or did his name slip from your radar?
I am wondering if the rotating radar antenna systems can be traced to the inventor Logie Baird. He was the famous inventor of mechanical television. He disappeared during the war and was later accused of being a coward in hiding. He claimed that he worked on secret projects and was not able to discuss them due to security issues. The rotating and imaging radar system is so remarkably like his early televisions, there is no doubt in my mind that he was deeply involved in the development effort. Could you possibly delve into this area and give us an update if the info can now be revealed after all these years? Thanks!
BTW, nice shirt!
While he may have been hidden away for war work, I doubt there was much connection between his TVs and radar, other than the TV transmitters were "borrowed" for early radar work. His invention was using a spinning disk, with holes in it, to scan an image.
@@James_KnottYes, but that bears a fair amount of resemblance to the way older analog radar systems synchronize the antenna, pulsing, and display. So it's a fair question.
Going from super duper top secret WW2 tech, to being in every kitchen & bachelor pad today, love it.
Same goes with peoples flat screen TVs, I know a guy who worked on the first flat panel multifunction displays for the USAF & NASA, started as mega expensive rare tech to being in everyones hand in a couple decades.
I know people that do not eat junk food => do not have it in the kitchen...
@@Bialy_1
What has junk food got anything to do with a microwave oven?? Smh!
@@jayytee8062Everything.
@@Bialy_1We are among those.
love your videaos mate, keep it up!
Thanks for yet another entertaining and well made video. Your topics and thorough research always make watching your videos a pleasure, and very educational.
Sir Mark Oliphant later on became the Governor of South Australia. After he retired I met him in the Naval and Military club dining room, while having dinner there with my Father, who was a member. We are proud of our Australian scientists
Great presentation! Here is a connecting anecdote (disclosure: I am a Raytheon employee).
Percy Spencer, credited with the candy-bar inspiration for the microwave oven, is also the Raytheon engineer responsible for the magnetron manufacturing innovation needed by the British. Percy realized that the cavities' flower-petal (or Colt-revolver) pattern could be (as mentioned in another comment) stamped out of sheet metal and the sheets bonded in a stack.
yes...the colt revolver barrel was used as a machine tool but the sheet metal stamped idea was brilliant
your narration was fantastic it was very easy and pleasant to understand and watch. Also an interesting subject you did a wonderful job putting this together. Thank you
Utterly amazing informative and entertaining presentation. An invention with a secondary purpose for good rather than the other way round. Thank you Mr Droid!!
12:17 crazy that in 1943 there was ‘little chance’ of the enemy recovering your aircraft from the sea when they are being downed by the dozen and just 80 years later the us has one single aircraft with all our new stuff on it fall into the ocean and we went through the process of getting it before one of our enemies could.
It's not that recovering a crashed vehicle from the sea was impossible back then - but it's a difficult and time-consuming operation which isn't particularly practical in war-time. A U-boat trying to salvage tech from a crashed bomber is easy prey when another bomber comes along to see what happened to his buddy...
@@cancermcaids7688 I was assuming the case of a plane which had crashed - shot down by a U-boat, perhaps - but not yet sunken. Yeah, once on the bottom of the ocean, no chance of recovery even in peace-time conditions...
I’d say other innovations brought by the Tizard Mission (the design for the proximity VT fuse, details of Frank Whittle's jet engine and the Frisch-Peierls memorandum describing the feasibility of an atomic bomb) were just as important as the cavity magnetron. 🇬🇧👍🏻😁
Also penicillin
Patents are generally published before a patent is registered. Everyone must be able to inspect what is being patented to discover prior art which might invalidate the application. Some twenty years on, the patent expires and it is available to all.
I can't remember where I heard it or read it but I once came across an item, at least a couple of decades ago, in which the shipment of a cavity magnetron from the UK to the US was described as one of the most important in WW2. I think the same feature also described a US physics professor attempting to explain to a student how it worked !
The major thing why the Tzard mission was undergone was the Brits didn't have the industrial capacity to build the Mags in quantity. When they revealed their little gem, General Electrics reps took one look at it. convened, and came up with an quick solution on the spot: punch press production.
Instead of machining each unit in one piece, they would use a punch press to create each layer of the Mag, then assemble and solder seal them together. It took a few months and the skills of MIT's Rad Lab to get it right, but it solved a ton of issues the Brits were having.
First it took forever to machine each one, and testing could not be done until it was completely built, and that took a month for each one. If it failed, then all that work was thrown away: there was no real fix when it was fully assembled. Punch press production meant reproducable quality in quantity was feasible, with QA performed with EACH LAYER. This meant if a flaw developed during production, the part was simply discarded, the dies were evaluated for issues. If the die was found bad, it was either redone, or scrapped and a new die put in. This took a handful of hours instead of weeks.
GE and Raytheon put this system to good work and Mags started to come off the line by the dozen. Mag production got so good, they were able to supply mission spares to replace bad ones while in-flight.
I think probably the Chinese are doing that kind of production technology work today.
@@philiptownsend4026 Back then, numeric control milling and lathe systems were a glimmer in the engineer's eye. It was not until the late 1940's when something barely resembling the turret mills and lathes of today came into being, but didn't sport the precision necessary for magnetrons or nuclear weapon components. But they could reproduce with cost efficiency.
The Chinese poached tech from one country or another to get where they are today. Their CNC mills are Pakistani, with German software and controls. The rest is polish and duct tape.
The magnetrons are an excellent example of die an tooling to make volumes of components, reliably and quickly. They didn't need high tolerance, but high production numbers. If a die develops a flaw and is picked up, that whole batch was scrapped.
Just about the only component in the old style maggies they had to pay attention to was beryllium. Dust from that stuff-instant lung cancer. Modern units don't use as much of that toxic metal back then, but it's smart not to tear one down because of it.
My grandmother had one of the first home microwaves. It was strange to see a microwave that had analog controls. There was no digital display. Just a dial you turned to set the time
I have one of those. It has two dials: Power and Time. It even has a physical bell that goes PLIIINGGGG when it's done.
My family had an Amana RadarRange in the mid-60's with the dials and bell. Big, heavy, and EXPENSIVE.
I have one too. Kinda nice that you can have a device that does magic without a need for smart electronics.
My great grandmother had something similar. I think it was an Amana. Their house was built in the 60's and they had money so all of their appliances were top of the line and matching. They actually had one that mounted above the stove. It had dials just like you described. Its still there, but I don't think it works b/c she had a smaller counter top one later on.
Her house was like a time capsule from the 60's. Puke green appliances, orange shag carpet, wood wall paneling, rotary phones, large CRT TV wall unit, ugly linoleum in the kitchen.
My dad bought a damaged 27 foot Travco motorhome in 1968. It had belonged to comedian Dick Smothers of the Smothers Brothers. We repaired it and used it extensively. My mom heard about the Amana Radarange and contacted them to see if she could get one wholesale for our motorhome. We planned a 2 month trip around the USA in it. Amana sent her one for free to ''field test'' it. We took the USA trip in the Summer of 1969 starting out from Los Angeles. Everywhere we stopped, that microwave oven was a huge hit. People were in awe of it like it came from outer space. Nobody ever heard of a microwave oven. Mom demonstrated it by cooking hot dogs, popcorn in a paper bag, and quick snacks. It cooked all of our meals on the road, many of them while driving. The control panel had 2 large twist dial timers, one for zero to 5 minutes, the lower one for 2 hours maximum. It was absolutely reliable in every way.
She wrote a full report and added recipes and sent it to Amana after we got back home. They were thrilled. Her contact person said that all 3 Astronauts on Apollo 11 were each given a Radarange. Being the first Moon landing (we were in North Carolina watching it on a 12 inch B&W TV), the Astronauts were quarantined in a special airtight Airstream trailer in the hangar deck of the carrier USS Hornet for 3 weeks. The trailer is still there in the museum ship. It has the same 2 dial Amana Radarange model we had. I'll bet that one still works. Neil Armstrong sent my mom a Lunar Mission pin and a nice letter after she wrote to him about the microwave oven that went around the USA.
I was fortunate to obtain my 1st Class FCC license and the radar endorsement in 1973 and working at the Ingals Shipbuilding on Spruance destroyers, the parabolic antennae and waveguide were cutting edge technology, I enjoyed the science and the work.
Very interesting and well done with an excellent voice for it. Well done, thank you
One observation: 9:38 we weren’t alone in the war. The Commonwealth was with us, sending us warriors from so over the world.
Why is that your priority to comment rather than praising our invention? Chances are youre not even British. Just the usual 'deflect away from british achievment' comment.
What is weird is that the WW2 Germans had better Radar than the British, but the British figured out how to use it better! Also, the Battle of Britain Radar System covered basically only their Coastline. This is why the British airplanes of the period had half of their underside painted Black and the other half White so that even an inexperienced Air Defense Observer could ID British aircraft from Germans.
Later on, the Germans actually developed an extremely good Radar Set, that the British had to do a Special Operations Raid on to get a unit so that they could develop a Counter-Measure that Bomber Command could use to penetrate Hostile Air Space on their (almost) nightly bombing raids!
If you've ever visited HMCS Sackville K-181, or have seen the movie: "Greyhound", what looks to be a glassed in all weather lookout station is a Microwave Radar Set!
The British were already working on a 3 cm magnetron to see subs snorkeling as that was the main danger.
Like most tech during that period, the Germans or allies will 'one-up' their version of a thing... Only to be out developed again by the opposition six months later.
The Germans may have been able to advance their RADAR later in the war, when a night time fighter with a RADAR set crashed on the Germans side. I don't know if it's a made up story or true, but the scientists that were given the Klystron, thought the little nuts that the pickup coils went through (the early versions had multiple c-shaped wire inside nearly all of the C cavities, not just the 1 that is seen in this video) were loose because of the crash landing. So they tightened them and thus never got it to work. The reality was that the engineered cavities were not highly machined, so by having loose nuts, this allowed a slight vibration/movement of the pickup coil. So an honest mistake but an ultimate missed chance at a big advancement in their technology.
The German radar was only technically better for the first couple of years of WW 2. After that, allied (and British) radar was vastly superior to the German technology, especially airborne radar. Witness those German night fighters with those large, external antenna arrays that sapped Bf-110s of performance and compare it with the neat, streamlined airborne radar that the de Havilland Mosquito night fighters had (and the first airborne radar was British, back in 1940, albeit a lot more primitive, but still nothing the Nazis had),.
@@mikemines2931 Actually the Germans didn't have snorkels until LATE in WW2.
And when you consider that when they captured Holland (1940), they got Dutch subs with Snorkels this is a head scathing moment!
I guess that this was another NAZI moment of Ours are so Superior to anyone else's equipment that we don't need to copy anything! (with the exception of the Czech tanks... which they kept in production in various variants)
Amazing content as always! Thank you for the beautiful story!
Another very interesting message mini documentary. Keep up the great work 👍
Whoa, pump the brakes there, Chief. Let's say that it _helped_ win the war.
I knew it! It just couldn't have been a coincidence the microwave makes popcorn better than anything. It had to have been designed from the start to make popcorn🤣 .....Oh and the Brits invented the cavity magnetron, but America figured out how to make them out of stamped sheet metal which made them insanely fast and cheap to manufacture.
Only the Chain Home transmitter towers were of metal lattice framework construction and the receiver towers were made of wood, not metal. If you look at photos of Chain Home stations, the receiver towers look more chunky due to their wooden construction.
quality production! thank you