The Microwave Oven Magnetron: What an Engineer Means by “Best”

The evolution of the magnetron - a device for generating microwave radiation - from World War II radar systems to the household microwave ovens illustrates how engineers think about “best.”
Learn More: Companion Book
Explore the ideas in this video series further with its companion book: The Things We Make: The Unknown History of Invention from Cathedrals to Soda Cans (ISBN 978-1728215754)
www.amazon.com/Things-We-Make...
Other videos in this series
Episode 1: Building a Cathedral without Science or Mathematics: The Engineering Method Explained • Building a Cathedral w...
Episode 2: Controlling Turbulence and Evolution: How Engineers Overcome Uncertainty forthcoming • Controlling Turbulence...
Episode 3: The Steam Turbine: The Surprising Relationship of Engineering & Science forthcoming • The Steam Turbine: The...
0:00 Titles
0:07 Engineering Notion of “Best”
The video opens by contrasting an absolute notion of “best” - the Renaissance ideal of da Vinici’s Vitruvian man - with an engineering relative notion as illustrated by the work of industrial designer Henry Dreyfuss, who developed drawings of ordinary people with their far-from-ideal proportions. Dreyfuss’s approach demonstrates that an engineering solution can only be judged based on how it handles the constraints unique to its situation - a balance of cultural forces, societal values, availability of material resources, and even urgency. This means that the notion of best changes with time.
1:04 Cavity Magnetron
The cavity magnetron, which powers mobile radar, was created by British scientists in early 1940 in response to fears that Nazi planes would bomb London. This device generates microwave radiation of sufficient power and of the right frequency to detect individual planes.
2:09 First Notion of “Best”
The standard of “best” used by the physicist-engineers who developed this magnetron was simply that it worked - prior to this nothing had sufficient power. The device worked in the laboratory, but now it needed to be mass manufactured to equip thousands of British, American and other allies planes and ships with radar.
2:42 Second Notion of Best
To mass manufacture the magnetron the British turned to Raytheon and their vacuum tube engineer Percy spencer. For engineer spencer, the notion of best changed: now the issue was one of prioritizing speed of production while maintaining reliability.
3:00 Tolerance Central Problem
The slightest deviation in the cavity’s diameter along the length of the cylinder would change the frequency of the radiation and blur the results from the radar. The tolerance was exacting: The diameter of these cylindrical cavities must deviate by at most one ten-thousandth of an inch (about 2.54 microns).
3:36 spencer Magnetron Compared to Prototype
A World War II magnetron, likely used in the Pacific Theater, is compared to the laboratory prototype.
4:16 Laminations
Bill explains how engineer spencer used a time-honored engineering rule of thumb - break complex problems into smaller, more manageable pieces - by creating thin layers, called laminations, which, when assembled, construct a complete magnetron.
5:44 New Notion of Best for Microwave Oven
To reversion the magnetron for an oven the idea of best had to change. At first the goal was to replace the conventional oven and to cook fast.
6:06 1946 Microwave Oven
The first microwave oven, which appeared in 1946, was aimed at restaurants, which is a commercial, not a consumer, use.
6:57 New Notion of Best for Consumer Oven
To become a household item - a consumer oven - needed a new notion of best as seen in the ads of the first successful consumer oven. They now aimed for a standard 115 volt outlet and an oven that fit onto a kitchen counter and into a household budget.
7:27 Evolution of Oven Magnetron
A detailed discussion of the changes from the World War II magnetron to those used in the consumer oven.
9:48 Mythical Story of Microwave Oven Invention
Bill mentions a likely apocryphal story, from a popular magazine, of the oven’s invention after a candy bar melted in spencer’s pocket.
10:14 Problems with Mythical Story
Bill explains how simple stories like a melting candy bar obscure the engineering method and strips away all the richness of how engineers create.
10:47 Review of Video Series
Bill review the engineering creativity discussed in the previous videos in this series.
11:10 Why Understand the Engineering Method
Hiding that creativity dissuades our best and brightest from recognizing engineering as a supremely creative endeavor, which robs us of the next generation of mental firepower, the new wave of engineers, who can help solve the problems our world faces.
11:27 Contact info
Bill can be reached at [e-mail] or at 217-689-1461 text/voice (use WhatsApp if outside US)
11:31 End Titles

[@kelalia]

I adore how he does literally the worse thing to get noticed by the algorithm (months and years of no upload, followed by short bursts of uploads) and STILL has 1,26M followers. Shows the quality.

[@chrissierzega8017]

I would love to see how many new followers came along during that hiatus. The videos all stand up quite well over time. Love bill!

[@asdf8asdf8asdf8asdf]

I'm sure he has thousands of requests and probably tens of thousands of ideas... Further this is probably been already mentioned on his channel but I'd love to see his take on Roman concrete which is significantly stronger than anything we make today

[@nicholasofthetube4557]

I guess his videos are meant for people that can override the algorithm 😎

[@nicholasofthetube4557]

also his youtube channel has the most simple name and unfindable by those 2 terms alone lmao ("engineer guy"

[@scottrobinson4611]

It's good content. Bill has such a knack for displaying the exciting engineering of many everyday items, while giving the greatest engineering sales pitch possible.

[@Tomary]

But when the world needed him most, he returned.

[@adamjosephbliss]

He's not the engineer guy we deserve, but he is the engineer guy we need.

[@peterjensen6844]

I absolutely LOVE the way the tolerance problem was solved by thinking so outside the box.

[@hedgehog3180]

Also just by ignoring it, stamping metal is quick and easy so it doesn't even matter whether it'll always work, you can make so many that you can still produce a lot.

[@hindugoat2302]

@@hedgehog3180 but... if the dimensions have to be super accurate... wont all the layers be slightly miss aligned? you would be less precise punching holes and layering them together

[@darkcoeficient]

​@@hindugoat2302you make one ver, very good "aligner" to always get them aligned properly.

[@hindugoat2302]

but your kind of making your problem bigger, now not only do you need to make and align these plates with precision, you also need to build the very good aligner machine, and many of its parts that require precision. You kind of passed the problem to the next part. @@darkcoeficient

[@nerdycus6935]

It's nice to have a living, breathing example of 'What an Engineer Means by Best' doing the narration for the video.

[@xjohnson42]

Beautifully and carefully written/produced. This is the quality of content which will stand for years. Hello ppl from 2060

[@aredditor4272]

Saw one error, he described the consumer microwave cooling fins as stainless steel, but they're aluminum, as cooling fins often are.

[@jimurrata6785]

These four new episodes have been great! I really appreciate your featuring the positives rather than the failure analysis we get from most engineering-centric sources. Hoping for more in the future.

[@markfryer9880]

Beauty, three more episodes to chase up and watch! As the son of a Civil Engineer, if Engineer Guy posts, it gets priority #1.

[@Adamk24]

@@markfryer9880 I can't agree with this enough, I love learning about the brilliant solutions and creative thinking that goes into the development of an idea from something that is exciting but flawed, into a new paradigm that becomes ubiquitous throughout the world. These triumphs don't get enough attention compared to the focus given to disaster response.

[@lukasaudir8]

The only bad thing now is that next video is probably 3 years away

[@engineerguyvideo]

I will try to do better

[@BoogsMcNoogs]

@@engineerguyvideo I'm no engineer but I think you're doing pretty ok already.

[@stephendoyle3352]

Bill it is so good to have you back. I think the work and effort you put in is amazing and I for one am TRULY grateful for all these new episodes and not forgetting all your previous works. All the best from Steve in the UK

[@engineerguyvideo]

Thank you

[@2MinuteHockey]

@@engineerguyvideo please show us the machining, manufacturing techniques, and process progressions of all the parts of the magnetrons discussed here

[@AutoFirePad]

I think that is your part in the process of learning , research :)@@2MinuteHockey

[@user60521123]

Welcome back, Engineer Guy! I’m so glad this channel is producing videos again. The content is so fascinating. .0001 is a heck of a tolerance, and machining the magnetron from solid copper would’ve have not only taken a week per unit but wasted material. Microwaves would have never become affordable. Not to mention needed a plumber just to install in a kitchen.

[@TimPerfetto]

SCCCCCCABBB HAIR PISSS POT

[@railgap]

If it takes a week to machine something just because it's made from copper, you need new machinists. Use sharp tooling with the correct geometry, a WATER based coolant, and correct speeds and feeds, and you'll have no trouble at all. Machining copper is one hell of a lot easier than machining titanium, which work-hardens in a single pass if the per-tooth pressure is too high.

[@iwanttwoscoops]

@@railgap dude, we're talking about 75 years ago

[@jackielinde7568]

Speaking of Magnetrons, I have some fun memories of playing with magnets from some. My father's a retired USAF radar maintenance tech. He would occasionally bring home a dead Magnetron and strip the twin horseshoe magnets from it. Those suckers were strong, and if you weren't careful, would do a number on any fleshy parts that got caught in the way. Never thought to disassemble the inside of the magnetron itself to see what it looked like. Sadly, that's a missed opportunity that won't come again.

[@abex701]

2 in a row?!! Am I dead and in heaven??

[@engineerguyvideo]

It’s 4 … they are a series

[@abex701]

@@engineerguyvideo I waited YEARS for you to come back, and WHAT A COMEBACK!!

[@danilooliveira6580]

you just said something I always thought, people like mythical stories about inventions and inventors, and sometimes even get angry when they read the real story because "it ends the magic". but it doesn't make sense to me, the details are the most amazing part of history, there is so much magic in reality when you try to dive deep into it. why would anyone prefer some mythical story ?

[@quintessenceSL]

The mythos of genius comes in two flavors I've noticed. One is the savant who can effortlessly solve some problem (ignoring all the years of study to have a base understanding of the problem to begin with). Or the flash of inspiration (ignoring all the previous failures that lead down this path). Both seem to ignore the everyday problem solving people do as routine. So it becomes a story of either gods walking among us or some simpleton outsider recognizing the emperor has no clothes; relieving people of the burden of trying and failing themselves (or at least not viewing their own successes as worthy).

[@Descriptor413]

@@quintessenceSL The worst part is that it can discourage people when they hit the hard work of inventing, because they feel like that difficulty means that they're doing something wrong, or aren't cut out for the task.

[@OptimusPhillip]

Plus, I don't think the myth and the truth are mutually exclusive in this case. The idea of using microwaves to cook food could have been born from a radar technician melting a candy bar, and that wouldn't invalidate the fact that it took many design iterations and innovations to make that idea work in a household setting. Then again, that radar technician came from my state, so I might be a little biased.

[@GoatBarn]

Right side/left side of the brain usage. Right side of the brain harboring more of the emotional response to a situation and the left side harboring more of the analytical (numerical/cold facts) response to a situation. The general population uses the right side of the brain (warm and fuzzy) for their decision making... (not to sound dismissive of the latter - there are proper places for it).

[@danilooliveira6580]

@@GoatBarn no, that is another myth that people spread because they like the idea of separating people in neat little boxes, and when I say its based on nothing they get angry because I'm a party pooper.

[@Kabitu1]

Great explanation. This is something I've seen alot of, people who fail as engineers because they're too rigid in their definitions of what quality is. They navigate on their own aestethic sense, rather than the constraints of the actual problem, and they like to imagine one type of solution suits every problem. Such people would enjoy the fine machining of the older magnetrons, and seeing the comparison at 8:50, would scoff at the less precise machining, claiming the angular holes are simply a worse design. When in fact the reason for the old precise machining doesn't exist when using it in a small consumer oven.

[@eypandabear7483]

It might even be better to spread the energy out a little in frequency space for an oven.

[@railgap]

You've seen a lot of failed engineers, have you? That suggests you've worked at a lot of lousy, incompetent firms.

[@kevinkoslowski2236]

As always after watching your videos I have a hard time finding the right words to express how much I enjoy them. I can imagine how much effort is put into every one of your videos. Please know that this is very much appreciated. Thank you so much for your work.

[@engineerguyvideo]

I very much appreciate your comment!

[@jimhowardbatey410]

As an EE, I understand the points that you make in this series. I hope the series inspires current and future engineers.

[@bort6414]

You might even say... Current and *potential* engineers... I'll see myself out.

[@GoatBarn]

Early 70's, home from school on a sick day, watching the Price Is Right, and the late Johnny Olson touting emphatically on a Show Case presentation, "...and this beautiful Amana Radarrange! with its modern cooking capabilities..." will forever be stuck in my head for some strange reason...

[@scottrobinson4611]

So 'Best' varies considerably with the specific requirements for an engineered product, it's so simple but a very important point to emphasise. I particularly liked the innovation to stack thin die-punched slices to produce a magnetron. A very elegant solution to the problem of requiring both high precision, and high production volume.

[@JoeOvercoat]

I’d be keen to see how they assembled those wafers into a single brick where they did seem to be spiraling in at least one example seem in the video… but that may have just been a demonstration piece not fully assembled yet.

[@44R0Ndin]

@@JoeOvercoat I imagine that they built an alignment jig (or given the production volume, numerous jigs) and just stacked up the plates as needed. Quite like how you would be tasked to assemble a motorcycle or hydromechanical planetary gear automatic transmission clutch these days, since the construction is remarkably similar between those two items (many stacked sheets held to fine tolerances).

[@JoeOvercoat]

@@44R0Ndin Those jigs must have had have high tolerance & calibration challenges is a production environment. So much so, that I suggest that would be worth a video on its own.

[@ToastyMozart]

Stacking stampings is a fairly common practice for other stuff too these days. The rotors and stators of brushless motors tend to be made like that to greatly simplify fabrication and reduce eddy currents, for example.

[@sysmatt]

This was a really great way to tell this story. The story of "best" to an engineer and how it changes based on context, time and situation. Brilliant. Side note, My dad was a master machinist and tool maker. He had a contract to make those super precise magnetron cavities for raytheon ... He told the story often. He loved the challenge.

[@Venator1230]

Good Health and Long Life to you, engineerguy. Thank you sincerely for your superb quality content on this platform.

[@borisxanovavich4466]

Hello there! Great to see another video on this channel. I started watching this channel years ago in primary school and it has inspired me to become an engineer. I'm about to finish my third year in engineering and start my internship for the summer. Thanks for being a great teacher.

[@engineerguyvideo]

This means a lot to me; thank you for sharing.

[@markfryer9880]

Well done Boris! The whole world needs Engineers, not Influencers! What branch of Engineering, Boris? Mark from Melbourne Australia.

[@borisxanovavich4466]

@@markfryer9880 I picked up civil engineering because my local university has an excellent CE program, but it was really hard to choose between civil and mechanical.

[@SquigglesZero]

I am a professional design engineer, 9 years in the business. When watching these videos I regularly find myself nodding an smiling. Really good content! And I especially love the message, that even people decades in the field forget, that it doesn't need to be perfect, but good enough.

[@Nill757]

More than “good enough”, but the “best” that can be done with the desired parameters, social, cultural, etc at the moment.

[@randytighe7150]

This is one of the most awesome descriptions of the engineering process that I’ve seen on KZbin. This video brings to mind another fantastic explainer of engineering practice. Back in the 1990s I discovered books by Henry Petroski - especially To Engineer is Human, a wonderfully accessible book that explores the relationship between engineering failure (example: metal fatigue cracks that formed in the early iron bridges during the late eighteenth and early nineteenth centuries) in driving advancement of the art. Make more of these please 🙂

[@engineerguyvideo]

Petroski’s work was a influence on me.

[@2MinuteHockey]

@@engineerguyvideo please show us the machining, manufacturing techniques, and process progressions of all the parts of the magnetrons discussed here

[@danidotexe_]

i see an engineerguy upload, i watch. i may be but a software engineer but the lessons in bill's videos and the principles they teach are equally as applicable in my trade as any other engineering trade. always excited to see you upload, bill. i hope you're well and thriving as you deserve to be

[@engineerguyvideo]

I am well!

[@ManuelBTC21]

11:10 "The new wave of engineers that will help to solve the problems our world faces." A positive vision for new bright minds. Thank you.

[@rashido_grey]

My heart is so full that new videos were released. The simplicity and easy of speaking helps get the point across without coming across as condescending. It's real information delivered in everyday language and I hope more comes at some point. Very well done, glad to see you well Bill.

[@ElectricGears]

The best 'explain it like I'm 5' description for how a magnetron works that I have heard is that it's whistle for electron instead of air(gas) molecules.

[@Melexii_]

Thank you for this mini series. Releasing them day after day has been delightful. I was originally expecting them one a week!

[@DavidGreen_au]

I remember the anecdote about the engineer and the chocolate. I remember, from the version I read, that he noted the effect, but didn't get back to it until well after the war.

[@n539rv]

As a retired engineer myself (and both my son’s are engineers), thank you for this series. You do wonders to explain what engineering is! Well done!! 🎉

[@human_brian]

Thank you for this new series of videos, Bill. They are fantastic and I hope for more in the near future.

[@scifactorial5802]

Does anyone know how they aligned the stamped parts? With the tolerances being so tight on the machined part it's impressive a similar performance can be reached with stacked sheets. Even stamping the sheets to such a tolerance by itself is impressive.

[@houseofcrazyman865]

I don't believe the individual sheets had to match each other as precisely as the single block of metal had to be uniform throughout. The stack is a whole bunch of tiny magnetrons pointed in the same direction rather than a single strong one. As long as your die is precise any imperfections in each sheet gets averaged out, where in the single block imperfections would be magnified by the size.

[@OOZ662]

To answer the basic question, I would assume the keyway cut into the edge of each ring was used to align them with the housing.

[@user-gr4sq3lo6n]

My dad was an Electronics Technician on an aircraft carrier in the Pacific in WW2 and worked on radars that employed huge magnetrons like the one shown in this video. Segue to decades later, I'm talking with him about the new microwave oven he had just bought. I mentioned that it was powered by a magnetron and he stared at me and said in wonder, obviously remembering those wartime monsters and said in disbelief, "It's powered by a maggie?!" I finally convinced him that it had been miniaturized, but I think he still didn't quite believe it.

[@shankarambady]

I just want you to know that for years now you changed how I think about things and that you are at the top of my “personal education list” of videos. you explain things so well!

[@Nexus_545]

Thanks for this series Bill! It's great to hear about the engineering stories that actually go on / went on behind the scenes. The Rule of Thumb for arch walls I probably never would have learned about otherwise!

[@scottaseigel5715]

Thank you Bill. When my wife left the Army she started college. I previously held a BA in psychology, but as I’d been teaching math and science, I decided to return to school. At the same time she earned her BS in microbiology, I earned about 50% of my BSEE. I love engineering and often dream of finishing, but sadly it’s an unlikely prospect. Your videos not only remind me of why I love it, but also that engineering is a widespread human activity from antiquity (with or without a degree). So again I say, THANK YOU!!!

[@dogownrpenna]

Welcome back! Thank you for returning. Your style of presentation is informative and comforting.

[@joebykaeby]

Even without new uploads, this channel never stopped being one of the best of all time on KZbin. Thrilled to bits to see your return.

[@matthewlennox9482]

Glad to have you back Bill! Love this video, will have to check out your new book! I like to say that as a product design engineer I’m always just balancing equations. Computers make it easy to do the number crunching now a days but we still have to balance the manufacturing techniques available to us, the material, make it cheap enough someone is willing to buy it etc. Design engineering is what you get when you mix algebra, manufacturing, and a bit of instinct together

[@rickhobson3211]

I am pretty sure that the plane pictured at 1:26 isn't being flown by Germans. I think it's being flown by a Finnish pilot in service with that country in a war with the soviets. Finland's uneasy association with the Nazis is really interesting history. Great video!

[@engineerguyvideo]

It is … sorry

[@Yordleton]

the Finnish airforce used a swastika in its insignia starting in 1918 for reasons unrelated to the Nazi party. Finland was officially prohibited by the western allies from using it after 1943, but is still unofficially the insignia used today. The fact that they both ended up as allies toward the end of the war and shared the same insignia was mostly a coincidence since it was already a popular symbol before being appropriated by Nazis.

[@MultiPenners]

@@Yordleton unrelated to the party, as it didn't exist back then. But not unrelated to the underlying ideology of racial supremacy

[@worldcomicsreview354]

​@@MultiPenners Oi, 'ark to this 'un, lads. Recks all swastikas mean "racial supremacy".

[@Yordleton]

@MultiPenners agreed. It was a convergent evolution of racist thought

[@GoodGoga]

Thank you Bill. This series has been a delight as always!

[@andrewshaver5800]

Bill, your content is so engaging and the presentation so easily digestible without being dumbed down. There aren't many better channels on KZbin. Thank you.

[@MikeOrkid]

Bill, you can make a video on the basics of anything and we'll watch it. You do such an incredible job at breaking things down, explain the history and the how to and it's like a perfectly tunes symphony. Here's to many more awesome videos. Thanks for you hard work.

[@ggroombr]

Absolutely one of my favourite channels on KZbin irrespective of the upload schedule!

[@abdulmominpanhwar6475]

Thank you for returning with such amazing content yet again!

[@brianredbeard]

absolutely delighted to see you back.

[@nepas3628]

You are a real master of teaching. The script, the pace and the simple but clever animations are so perfect for the understanding of everything you want to teach. I wish I'd have a teacher like you in college. Learning would have been an amazing journey. I'm glad you are back, your videos always wake up that children inside me who wanted to build things and solve real life problems.

[@roadrangermy4354]

Love your videos, very well researched and extremely well articulated. Thank you for continuing to make these!

[@rpkamins]

Love these back-to-back uploads!

[@hunterhalo2]

You are your channels team are champions. Thank you, and thank you for coming back.

[@garypate3201]

Ok so I’ve just discovered your videos literally today and I can’t stop watching them , I’m no engineer but I’ve always been told I think like one , I guess it’s just how my mind works , I’m so thankful for your videos and more opportunities to learn stuff on a deeper level.

[@techwiz81]

This miniseries was great, looking forward to more of your videos in the future!

[@tonycmac]

Its good to see you making videos again - as usual, your work is delightful!

[@Leo9ine]

Glad you're back! Commenting to get you back in everyone's recommendations

[@underscore_lol1378]

Holy crap this upload rates insane I’ve been waiting 2 years for this

[@engineerguyvideo]

I will stop now … putting all the stuff away now in video and working on next video … some I posted a picture on Reddit showing the studio covered in all the stuff from this series

[@FlakeSE]

Concise and precise as always, I bet you could go on amazing tangents.

[@playmaka2007]

Clear, concise, informative. Glad to have you back!

[@N1njaSnake]

Sir, I just want you to know how much I appreciate your videos and how special they are among all the others on KZbin.

[@colesurf]

so excited to have you back

[@artvandelayimports]

Absolutely love this series! Also, I want to thank you for these videos, they brought UIUC to my attention over 8 years ago and I just graduated with a bachelor's from them this weekend!

[@matthewjackman8410]

Congratulations!

[@frunomaol5069]

Good to see you back in action. Thanks

[@Blue_Camera_Cat]

I was genuinely inspired by your early videos when I was growing up. I just discovered your recent uploads and I'm so excited that you're creating amazing content again!

[@Wheels-of-terror]

What a great video series! The microwave always fascinates me because I get so much use out of it and it's just a really interesting device, seen other KZbin channels do some crazy stuff with them. So what's next? Any hints you can give us?

[@bladder1010]

I really appreciate how Bill draws out the subtle yet incredibly important aspects of a concept that are often overlooked. One of my favourites!

[@mrbourdet]

Bill! You are back! I have enjoyed your videos. Glad to see some new ones. Good luck with your book.

[@cmflyer]

So glad you are back! Great video!

[@therealxunil2]

Oh BOY. new engineerguy episodes! I've loved your shows since I was in grad school at uiuc, hearing you on the radio.

[@dominicesquivel3901]

Isn’t he supposed to be dead? Like literally passed away?

[@Leo9ine]

Thanks for the video Bill. A question - Do you have more information about the process of stacking the laminations of the wartime magnetron? I'd think perfectly aligning the holes would be more difficult than machining the solid design. Not to mention the multitude of surfaces to keep perfectly clean/corrosion free. Feels like more potential for error. Maybe the limiting factor wasn't precision, but simple time of manufacturing. I'm surprised it worked! It makes intuitive sense but I wouldn't have trusted the idea if I'd come up with it. Suppose that's why I'm not an engineer!

[@christianweagle6253]

I am both a machinist and an RF engineer and I, too, have many questions similar to yours.

[@matthewjackman8410]

I am not an mechanical engineer or a machinist, I work in IT infrastructure so I may be very ignorant here. My assumption was that one or many sets of rods was produced at the specified measurements to be pushed through the plates and they were then sealed in some way, by welds or otherwise, to a base plate at the correct positions.

[@rikbootsman]

Have been waiting for a new episode! Thanks!

[@SapioiT]

These latest 4 videos, published in the last 3-4 days, are top-tier quality. Please make more such videos! Those 4 videos are the only reason I subscribed and rang the bell to get all your new videos recommended to me, and I'm looking forward to more similar videos. Keep up the good work! I wish you the best!

[@broheim23]

Wow, excellent video! 👍 I'm an IBEW wireman by trade, but have toyed with the idea of getting an EE degree off and on for a few years. This video definitely gives me the motivation to get started on that path sooner than later.

[@Trenz0]

I'm in my third year of university for mechE after having worked various jobs before starting. Do it! You'd be surprised how many people in engineering are in our same boat. If you have the smarts and, more importantly, the drive/willpower, go for it!

[@northjoe]

You need to do audio books! I would totally get listen to them all.

[@kiowablue2862]

Indeed! Part of the reason for watching Bill's video clips is the _delivery._ His voice reminds me of broadcasting greats Charles Kuralt and Charles Osgood.

[@steveneiselen7993]

Excellently prepared and performed discussion as always, Dr. Hammack!

[@kjamison5951]

Thank you, Bill. You don’t dumb anything down. You just state the facts and we love it!

[@russianbear0027]

Thank you for making this. I'd never understood magenetrons. Are military and aviation magnetrons still built with the stacked plate method? After all that tolerance is still fairly difficult to achieve Its also nice to see you back. I'd figured you were done with making videos.

[@nerd1000ify]

Magnetrons are obsolete in radars. The frequency fluctuates from pulse to pulse and as the device warms up, so they can't be used with the Doppler techniques employed in modern radars.

[@russianbear0027]

@@nerd1000ify that's fascinating!

[@tinymonster9762]

@@nerd1000ify The company I worked for up until retirement last year makes thousands of magnetrons for marine radars where they are cheap, powerful and effective.

[@cdorcey1735]

@@nerd1000ify Not all radar applications require Doppler-measuring stability.

[@raccoonofmotivation20]

The Engineerguy may not make videos often, but they are always the most enjoyable and enlightening ones on youtube when he does.

[@DrDamoStrikesBack]

As a career engineer I love hearing someone speak with such genuine love for engineering and explaining it in a way that can lift the lid on an otherwise misunderstood and sometimes completely hidden profession. The Egineerguy embodies all the best parts of human inventiveness and curiosity. Well done!

[@kendigjl]

So happy to see you've made new videos!

[@patrickkwok125]

amazing work bill, might want to change the thumbnails though since it looks like its an audiobook which is probably why this isnt getting as many views as you usually do

[@engineerguyvideo]

Good suggestion… and … done!

[@GeoffryGifari]

on spencer's design of the magnetron (where slices are used instead of one metal cylinder), it seems like aligning those plates to fit the tolerance is a feat in itself

[@abyssaljam441]

I know nothing about magnetrons but it could be that the tolerance only matters if the bits of metal are physically connected.

[@amessman]

One of the two or three times I have subscribed in the first couple minutes of a video. Absolutely fascinating!

[@LikeOnATree]

Amazing video, so glad you are back! Thank you very much for your hard work!!

[@Maxchillin420]

Reports of engineerguys death have been greatly exaggerated

[@TheFlyingScotsmanTV]

Best or 'best quality' - I struggle with my IT 'engineer' colleagues all the time over this. They just don't get it. To them best or best quality means they spent massive manpower on it making it the absolutely best bit of code thingy ever. it will do x, it will do y, it will cure cancer. The customer is rarely happy that their thingy cost 100k. For me though best means - FOR the purpose - performance required, cost required, efficiency required, lifespan required. I knock the thinhy out for 1k. customer is happy. But as far as my IT colleagues are concerned this is a compromise they don't want to make. My analogy is that if it was up to them designing a car, every car would be made of gold, go at 200mph and sit 50 people. customer: "but I want a car to drive to the shops with the wife". IT 'engineer' - this is what you need, it will not only do THIS, but is reusable and extendible - and can take up to 48 of your friends AND travel at 200mph. why do you not want that ? sigh..

[@cliffmathew]

Really glad to see you have resumed your channel. Thank you

[@lajoswinkler]

I am glad you are back. Great video and great point at the end.

[@xtieburn]

Okay, but could we take a step backwards a moment, because I kinda want to get a microwave dome. More seriously, wouldnt the dome help causing some chaos in the microwaves producing a more even cook? I guess the rotating platform was a safer easier option.

[@Rivek]

I can't tell you how great it is to have you back producing content. Thank you!

[@godnessy]

So great to see you posting again Bill! I think I have been subscribed to your channel for at least 10 years now!

[@cornholeyoursister]

I am beyond excited to see you creating content once again. I still watch your old videos in a Playlist from time to time.

[@thomaswade3072]

Love seeing your work again Bill!

[@jeanduponte4056]

Thank you so much for making these videos again!

[@chriskeffer]

Another great episode! Great to have you back.

[@JaySmith91]

Truly top-notch explanations. I really like the hands-on show and tell of the guts of the magnetron. In someone's hands, it makes the technology seem real, tactile, deceptively simple, and also shows the actual scale of the parts.

[@randyhavener1851]

Excellent as always!!! Thanks Bill!

[@matthewjackman8410]

Great to have you back Bill! You always remind me of the amazing progress by great minds that has made the things which seem simple today, seem so simple.

[@vincejohnm]

One of the best on KZbin. Glad you’re back Bill.

[@hobojakobo]

Bill has a knack for explaining complex things in a way that people of varying ages and backgrounds can understand. This is what makes his videos so awesome. Glad to see you posting again!

[@audiokillerr]

I just find out there is a new series!!! Woooohoo!! Thank you for taking your time to make these videos! 😃

[@Srinathji_Das]

Thanks for this beautiful video! We missed you. ❤

[@natewagner55]

So great to see the new video... I was just thinking the other day about the aluminum can episode you did years ago. Such a great breakdown of the fantastic inventions used so commonly we just take them for granted now. Thank you!

[@Yeebok]

Welcome back, great to see you again !