Triode Vacuum Tube: History & Physics

[@AbhishekYadav-jq5zo]

One of the best way to understand a scientific discovery is to understand its development process and your videos provide that perspective. I highly appreciate and thank you for all your efforts.

[@Kathy_Loves_Physics]

Abhishek Yadav thank you for the lovely comment. I started this thinking that I would learn some interesting history but I have been amazed at how much science I have learned through its history.

[@gordonquickstad]

This is a terrific introduction to birth of electronics.

[@brucewinningham4959]

Kathy is the Greatest at what she does! Well, she may not be the Greatest but there is NONE better.

[@dennisfahey2379]

I believe that is because in its original concept the problem and solution attempts are extremely logical. You can see the trial and error and how a new phenomena is discovered and slowly understood. Then comes the formalization of the topic with committees and creation of a specialized lexicon/jargon. Yes they have value but they obfuscate the underlying truth.

[@devarakondapratyusha]

Been everywhere in the internet to know about vacuum tubes but this video is simple and far better than everything.

[@Kathy_Loves_Physics]

venkat sivaprasannakumar so glad you liked it. Strangely, I think it helped that I knew nothing about vacuum tubes a year ago! Starting with the history really helps IMHO. Also, the old army videos are pretty good. Cheesy but good. I wished I had watched them before writing my videos.

[@GuyRBrewer109]

Looking at the picure of Edward H. Armstrong, you can plainly see that he was a passing negore. I think people knew and kept his name out of the record books because of it. The same way they did Lewis Latimer. It's plain to see that Fleming used Latimer's Filament in his design. The two also worked together. So far in this series, you always mentioned Edison's name with the lighbulb, when history says it was the design of Lewis Latermer! Latimer wrote the first book on incandescent lighting and set up the lighting system in London England This same blackman came to court to explain the telephone of Graham Bell when at that time, a Blackman could not testify against a white man. Why was there an exception for Lewis? He worked in Edison's lab and Bell labs. History relegates Latimer to a "Drafter" of the telphone, obviously minimizing his contributions. Less than 30 years after slavery, a Black American contributed heavy into America's largest industries Electronics and Enginess (Transportation) ELIJAH MCCOY and the automatic oild pump. I like how you pointed out how all of the women who were left out of the history though!

[@seanbryant2848]

Edwin Howard Armstrong was my childhood hero, and is still to this day! Thank you for bringing this all back into a public forum, as this is such important history of early electronics, and the geniuses who made it work, and the charlatans who rode on their coattails.

[@seanbryant2848]

@@Poschet0423 🤣🤣🤣🤣

[@ronjon7942]

AMAZING, Kathy! For years, decades, I wondered on the entomology of "diode," but not enough to research it myself. Diode - two path. Ode to Joy! See, this is why your method of combining science and history is so perfect. I still have my Dad's Heathkit radio and amplifier - one step closer towards opening it up and see how it tics.

[@amitpatil5151]

Madam, I Like Your Work. You have Wonderful Knowledge. Very Few People tell Us History of Science. You are Among those People.

[@Kathy_Loves_Physics]

So glad you liked it and thanks for becoming a patron!

[@dhisnadhamayanthi1135]

Iam from Sri Lanka and already 59 years old i had the opportunity to learn of vacuum tubes nearly 48 year's ago in my school age and we are the final generation who learnt about vacuum tubes in our country

[@stephenpuryear]

A fascinating story of a bunch of really smart people stumbling in a generally right direction!

[@amritpatel3794]

I love the way you start from the "beginning" and authentic supporting document images.. That set you apart from "Hollywood story".

[@lawrencecohen1619]

Kathy Thank you so much for this video. I have been an electronics engineer for almost 47 years but would like to know more about the developments that propelled the electronics revolution. I think your videos have greatly enhanced my discovery.

[@Chris_at_Home]

I love learning the history of things I worked on. I first learned about tubes in high school in the late 1960s. At 16yo I had an apprentice license for TV repair. I wasn’t supposed to make house calls till 18 but the two men I worked for considered me qualified to do so. Imagine a 16 yo kids with a tube caddy and test equipment showing up at your house. I went into the Navy in 71 and they taught us both tubes and transistors. We’ve come a long way since then.

[@Kathy_Loves_Physics]

If you consider the fact that the television was invented by a 14-year-old, it makes perfect sense that you were qualified to fix them at 16! I bet you did a better job than the adults.

[@Chris_at_Home]

@@Kathy_Loves_Physics I had a successful career working in electronics. I have worked extensively with fiber optic, digital microwave and satellite down to breaking out all those little circuits and testing them. I also did some trunked radio. My phone rang a lot for advice. Heck, it still does from time to time and I’m retired. during my free time I built houses, worked on my own vehicles even rebuilding engines and automatic transmissions.

[@Kathy_Loves_Physics]

Wow!

[@youme112233]

I worked for aTV repair shop when I was 16 ~ 17 . After I made a few service calls by myself , the boss said I needed to grow a mustache and beard , because the lonely housewife customers complined and said I looked too young .

[@timjohnson1199]

I'm a mechanical guy working in a place with a lot of big tubes (megawatt output each). This helps.

[@gristlevonraben]

They could make movies from your stories! Thank you for sharing all of this with us.

[@eddiepires3998]

I have made a career in the fascinating field of electronics and work with SMD everyday and still love the vacuum tube . Even though I knew about the Thermionic effect and these smart experimenters , I didn't know about the smudge . Thank you for your interesting video because I learned about a detail I had never come across .

[@PeterMoses123]

Kathy, love this video. You've done a really great job explaining this. Great to see.

[@Kathy_Loves_Physics]

So glad you liked it. I learned this stuff through its history so I am often a little nervous that I got it right (on the other hand, it might have helped me to learn engineering so long after being comfortable with Physics so who knows).

[@FrankScotsman]

This was really interesting. I've heard bits and pieces of the history before and getting the details was great.

[@roberthigbee3260]

I give you the coveted triple wow (never before given) - wow, wow, wow, wow! A crisp precise and excellent description of electronic amplification melded with intrigue including plotting con-men, whats not to like! Shows how "luck favors the prepared mind", you madam are an explainer extraordinaire!

[@Kathy_Loves_Physics]

Thank you for the coveted triple wow (with a bonus wow for good luck)! I appreciate it. - Kathy

[@roberthigbee3260]

@@Kathy_Loves_Physics - Yes, I now see that in my exuberance I did give you a bonus wow! I just willy-nilly went from a double wow, past the triple straight to the quadruple. I guess my inner self disagreed with my outer self and felt you deserved the extra praise. Honestly, the biggest thrill of KZbin is getting feedback from the content's originator, especially one of its titans like you. Make no mistake, while you "only" have 98.1 thousand subscribers, you really represent the top half-of-one-percent of presenters, in my opinion. So what some 16 year old making arm pit noises and/or jumping into his parent's swimming pool filled with jello have a million subscribers, you not only have your own self respect, but also you have the respect of 98,100 extremely discerning, but perhaps counting impaired as is the case with me, viewers applauding your content and being enriched by it. You give me hope for the world. You help keep the tent of knowledge upright that is seemingly eternally being buffeted by the chaos of our conspiracy mesmerized society.

[@klausziegler60]

This is just fascinating. Thanks, for your stupendous research on the history of electricity.

[@NotMarkKnopfler]

Superb! Thank you for this brilliant historical summary. So interesting! I thought there was some science to the design of the vacuum tube - but it looks like (at least initially) it was random experimentation. Only later, when the engineers understood the physics taking place within the tube did the design lend itself to optimisation. Fascinating! Thank you, Kathy!

[@dammitdad]

I am so pleased to have found your channel. Your presentations are well thought out with good common sense flow. I expect your children are blessed to have been brought up in an enquiring and interesting home.

[@thedouglasw.lippchannel5546]

I finally understand the vacuum tube. Thank you soo soo much.

[@petercollins4516]

From France. Incredible how good is your very clear explanation. it s a real pleasure to find out how the all thing works...With You every thing seem so simple. From a admirateur . I will be there quite often listening with attention your next presentation. Lot of thanks. Peter

[@ciemo87]

I can assure you The type of your channel and videos will go very deep in history and will live very long, I have a degree of electronic engineering but didn’t know anything about these stuff and how they work, also I know thousands of double Es in the part of the world where I live with the same condition, I learned about Fleming valve while reading a book called “Empire of Air” and wanted to see how it looks and works then search brought me here.. thank you ❤

[@Kathy_Loves_Physics]

Isn’t that book fabulous?

[@st.charlesstreet9876]

I just have to stop and say these posts that you make are the most interesting and fascinating videos on the discovery of electronics! Wished that I had you for a History Teacher 😄

[@trespire]

In multi kilowatt industrial lasers, we use vacuum tubes / triodes to switch 9 to 12 KV resonating at 80 Mhz, on and off to control the CO2 laser source. The tubes are from Thales, anode voltage is up to 12.5 KV, grid is at -200V and switched at 60Khz. The tube is cooled with deionized water running through it, the ceramic insulation glows a bright orange when run at full power.

[@greghampikian9286]

Great explanation! Thanks for explaining the grid input in the amplifier so clearly.

[@antoniolagos]

This channel is a gem. It certainly deserves a lot more views.

[@aminnima6145]

The history of physics is fascinating...so many amazing people with so many contributions

[@Kathy_Loves_Physics]

I agree.

[@stuckp1stuckp122]

Excellent explanation of how vacuum tubes evolved!

[@aypankaj]

Kathy incredible work, when you understand the flow chart of development in science you understand whole since better Thanks for your efforts I request to write a book about it in your own way God bless you

[@Kathy_Loves_Physics]

Thank you so much that was lovely. I have finished my first book “The Lightning Tamer” which is on how electricity got into the home and it is up for pre-sale on Amazon and from the local bookstore. When that dies down I can focus more on my second book which is on the history of wireless including stories like this.

[@spankyharland9845]

in Europe, they called them valves..... early WW2 electrical equipment had miniature vacuum tubes- and currently many people prefer tube stereo amplifiers because of the nice mellow sound they produce.

[@AndrewLohmannKent]

When I was at college we briefly learnt about Valves and those old fashioned in the UK and Europe Pre-SI units used to specify them. That was in about 1975-77, otherwise, transistor, inductors, capacitor stuff was all SI units. I made a few things with valves that I could get to work more easily than transistor circuits.

[@AndrewLohmannKent]

This super-regenerative TRF radio works very well (page 43) I made, back in the 70s when I was a teenager it but without the reaction, as I was concerned not to broadcast rather than receive.

[@gerardcousineau3478]

Kathy this video shows greatly that the vacuum tubes ( amp ) were not the invention of one man but men taking the knowledge of each others to create the electronic era, we're still in this era, me texting this with my smartphone is something from SciFi a few years ago. Electrical devices and everything that surrounds it won't be going soon. The vacuum tube with the plate the cathode and anode is the father of the transistor. I really like my tubes guitar amplifier. Thanks again for your excellent videos. And like many others here, I'm waiting eagerly for the next one. 👍🙂 Thank you.

[@brianshanahan3878]

Awesome coverage of the material!

[@Kathy_Loves_Physics]

Thanks for watching

[@marksadler4104]

Still using them😃 Building guitar amps. Currently building a clone of a 1938 Gibson amp which includes a field coil speaker! Taking about patents, us Brits had the pentode patent The Americans requires a licence to manufacture them, however as the Americans are not keen on paying the Brits ( nothing new here from what happened at Boston😂), they came up with the beam tetrode which essentially does the same job but the internal layout of the valve (tube in the US) is different, effectively bypassing the British pentode patent.

[@ecbftl]

Thanks, this was a very interesting history. I was familiar with the names of the inventors, but the relationships and timeline of the early development was interesting. Some years ago I worked at the Canadian Marconi Company in Montreal, and found in the company library some of the early engineering journals from about 1909 describing Tube circuits. I had studied Tubes in my high school electronics courses, so finding the journals was fascinating. I think a lot of these historical documents have been donated to the Marconi National Historic Site at Glace Bay, NS in Canada.

[@lancekiel1467]

I just found your channel and I plan to binge watch them all!!!!!!

[@DougDingus]

Subscribed. Your enthusiasm is a lot of fun.

[@huangchao5164]

important details in the invention stories in this series vedio,great work of kathy!

[@Kathy_Loves_Physics]

huang chao thanks! Glad you liked it

[@bobsnelgrove7930]

Very well researched and accurate. Also technically detailed and well presented (and funny). Also, when you really know your stuff you can keep it short and this is key. Thanks!

[@stephenwilliams5201]

70 years old. And 51 years a radio operator. Worked for army/general telephone and electric. Sylvania. And still learning tks. De kv4li 73

[@Kathy_Loves_Physics]

That is awesome. I don’t understand people who stop being interested in learning new things - I am honored to be part of your continued education

[@stephenwilliams5201]

@@Kathy_Loves_Physics l am a bit of a tinker . And built my own solar power/heat plant. So I use little in carbon. Gas for heat in cold winter. So some build clocks, ships in bottles, and I build radios. On cold winter nights. To labour all evening. Then do the "smoke test" and hear that radio gasp it's first few seconds. Then the voice/music comes thrugh. Is victory! A good life to you. 73 de kv4li

[@LuciFeric137]

I remember going with my Dad to Radio Shack and using their tube tester. Dad kept all our TVs running DIY style.

[@gumbilicious1]

This is the most entertaining science I have consumed since I read bill brysons a brief history of nearly everything

[@Kathy_Loves_Physics]

Wasn’t that a fun book? Thank you so much for the giant compliment.

[@SevenDeMagnus]

Thanks Kathy, extreme skills. That sort of accidental addition (lol, De Forrest was just kind of guessing but he is the inventor of the vacuum tube that paved the way to chemically done transistors) of the collector or drain was the key to controlling the amount of electrons (or none) to all our deep learning today and internet and computers (but most likely not tomorrow with advancements. in quantum and room temp superconductors). Create a nixie tube history and documentary :-) God bless you.

[@augustodanelus]

Congrats!! Your explanation is perfect, there's no video like this..

[@boredout43]

Again, just discovered your videos and am really happy I did, strong work!

[@codaalive5076]

I like hearing woman talking about tubes, it is a lot more relaxing than always have man in this circles. Thanks for telling us this story.

[@DrPG199]

First, let me say that I like your videos; I find them interesting and very well supported. However, I don't think it's fair the way you speak of Lee De Forest. He invented the triode, and yes, that grid between the filament and the plate made a huge difference. That was a great invention that changed the world of electronics. You may dislike him because he was in several disputes about other patents, but the way I see it, Lee De Forest came to this world to invent the vacuum tube triode and we should be grateful for that achievement. It was not just "a minor" modification of the Fleming valve. Best regards.

[@ronjon7942]

Well, she did credit the conman his due. And he was a crook, con artist, thief and a liar. But to think someone or a team of knowledgeable engineers wouldn't have invented this in stride is pretty naive. Also, Kathy's hardly the only historian to call out this attention loving charlatan.

[@DrPG199]

@@ronjon7942 Did you read my comment entirely? Kathy and everyone else credit Lee De Forest with the invention of the triode which preceded the transistor. That was a HUGE advancement. That he wasn't a good person, I don't care. Most people are not good people, anyway.

[@DrPG199]

@@ronjon7942 Do you understand the difference between a diode and a transistor? It's a HUGE difference, they're not comparable because they serve different purposes. That's what Kathy calls "a minor change", please ....

[@Kathy_Loves_Physics]

The transistor came far after the trial. The triode with a minor difference from the diode. And although it had major impact, at first leader forest tried attaching many many things on the inside, and the outside of the diode so it seems strange to me to think that the trial that was particularly well thought out, although it was very impactful.

[@DrPG199]

@@Kathy_Loves_Physics Let me explain my reference to the transistor. The transistor is functionally equivalent to the triode. Any electronic circuit built around vacuum tube triodes can be easily replaced by an equivalent circuit made of transistors. Nobody would say that a transistor is a "minor" change to a diode. The audium (triode) was a HUGE fundamental change that gave rise to what we now know as electronics engineering. It was the way we could design amplifiers, modulators, and oscillators. The first vacuum tube computers were built around those triodes. We now do it the same way (functionally speaking) but with CMOS transistors, for obvious reasons. But the Von Neumann architecture of those vacuum tube computers is still used in our cellphones. Function vs. physical construction is something that needs to be considered. Going back to the Fleming valve, it was a judge who decided it was a "minor" change, because, well, I don't need to explain, his background? But the patent owner, Marconi, saw that it was not a "minor" changed and decided to share the patent with De Forest.

[@swangleewatanakarn7701]

I start to addict to your channel. Good job.

[@AFRFB09BA]

Thank you so much for this lovely piece of technology history.

[@paulm1241]

8:04 To be more precise the grid amplifies voltage rather than current: a small voltage change on the grid produces the same change in current as would do a large voltage change on the cathode. For this reason in order to get good amplification we have to connect the cathode through a high impedance to collect these voltage changes on the cathode.

[@canuckprogressive.3435]

Yes. The tube amp has a high input impedance unlike the bipolar transistor.

[@dwightmanuel1609]

An excellent presentation, thank you

[@sampangi99]

Very Informative Video Kathy, my curiosity why in first place the vaccum tube was invented is quenched by your video

[@Kathy_Loves_Physics]

Glad I could help.

[@frederickwise5238]

I am finding these videos fascinating. My 1st "bout" with radio was in 1943 (7YO) strung a wire from a metal thingie on top of a tube in the old Zenith (Thank goodness it was a grid not a plate LOLOL) and I made static which interfered with the war news. I got paddled. Greatest treasure I ever discovered accidentally was "The Boys Book of Radio" in the school library, 5th grade 1946. I didnt know much about "condensers" or "Impadence" or why you had to wind so many turns of wire around a Quakers Oat box but I did get a crystal set to work sorta. That book taught me the color codes and I bummed a bunch of 1930's junk radios from a local repair shop, only got a one 27 tuber to work for B. Scouts 1949. 1952, built a Radio Shack Knight kit 2 1S5's, SHORT WAVE - THE WORLD, SOLD ME.!!!! and radio/electronics became a career that lasted all the way thru the Navy as a CTM and eventually on into computers to my retirement in 1994. BTW I hate solid state An old man reminiscing. Sorry..

[@ronb6182]

Fredrick Wise It's ok tubes are better than transistors for audio amplifiers. If you have good transformers on the output you will get good sound. You will not get tube sound at the preamplifier stage you must have a good iron core transformer on the output of a 6BQ5 or 6CA7 or equivalent. I tried them headphone amplifiers with the single tube. I looked inside and 12 Volts on the plate and grid is a joke there is also a solid state amplifier inside that tin box. You can only fool me once. I love my dynaco amplifier. I need to recap and probably get matched quads for the amplifier. I want to keep it original. Magnavox also made good tube amplifiers.

[@frederickwise5238]

@@ronb6182 Few people realize the truth of what you have said.. For me it doesnt matter much anymore. Ive lost the upper two octaves in both ears working around industrial machinery before OSHA.. In my 20;sI was tested, able to hear up to 26K, now I can barely hear lightning. LOL

[@ronb6182]

@@frederickwise5238 see the problem is the younger whipper snappers haven't grown up listening to tube electronics. I played with tube electronics since 7th grade. I remember AM radios sounded like stereo when they played classical music and beautiful music genre. I never had an FM radio but my friend had one. I got my older sister's stereo console which had FM later like one year later. After hearing a rock song on a dynaco st70 (another friend had one) and hearing the same song on a transistor stereo the dynaco won. The bass was richer on the dynaco. The transistor stereo was flat sounded. Then you got older transistor sets that sound better than new amps. I prefer the tube sets over all transistor sets. My hearing is not as good as it was but I can still hear the high notes. I have headphones that blot out sounds that are harmful to the ears at my workplace.

[@frederickwise5238]

@@ronb6182 The "phenomenom" to which you refer relates to the rich overtones or harmonics. that transistors "cant do" I suspect that the streams of electrons in tubes can "ring" (dont know what else to call it) and the magnetic fields of good quality output transforemerw do much the same. These provide the timbre that tansistors cut off. But when you no longer hear above 8K or below avbout 250cps it matters little. LOL

[@ronb6182]

@@frederickwise5238 you said it better than I could. I have a few transistor amps I might try putting some iron between the output and speaker. I have a few isolation transformers at work. I will post what I find out. May even hook a scope to the output. I used to have a scope hooked up to one of my stereo channels. In my youthful years.

[@jmguevarajordan]

I do not know too much about it but l think that Deforest knew that his triode was an electronic amplifier and used it without feedback to design primitive radios receiver and transmitters. In fact such radio circuits were taught in high school physics, many years ago, because they are relatively easy to understand. Armstrong discovered the way of making electronic oscillators with the triode by using a feedback circuit. Armstrong used it to create the regenerative and super regenerative radios which outperformed the primitive Deforest radio. Armstrong circuits were a long way more complex and unstable than Deforest primitive circuits. Armstrong's oscillator is the key component of the superheterodyne radio, the most successful radio design. Armstrong became rich with it.

[@augustot.pareja8795]

I read a book long ago and the history was very different. It bothers me the treatment of DeForest as a "con man". After I read this book, DeForest is to me the father of electronics and the victim of giant AT&T at that time. I would like to know what sources have Kathy about DeForest. I had watched other Kath's videos and found them very respectable and interesting. The author's name is Israel E Levine, and the book is Electronics Pioneer (c 1964).

[@jmguevarajordan]

@@augustot.pareja8795 you are correct, Deforest discovered the first electronic amplifier and he has his place in old physics textbooks. However, modern books about history of radio present him as a villain and dishonest person (see 'science of radio' by Nahin for example), so the video is repeating those opinions. Certainly, Deforest was not a 'nice' guy but if Marconi got a Nobel prize then it is fair to say that Deforest deserved one, by accident, too.

[@OuttaHere7]

You are a gifted teacher!!! Many thanks!

[@frankmccann29]

Thanks, Kathy.

[@ver64]

You earn my subscription, excellent info. Thank you 👍🏻👍🏻

[@Kathy_Loves_Physics]

You are welcome! Thanks for subscribing and commenting

[@bombadeer8231]

Much appreciated Kathy 🙏

[@robbirdjonesanimal8869]

Thank you, please more

[@hasanatkhan940]

Thanks for the amazing explanation.

[@nakkamarra]

Great video Kathy!

[@MicrobyteAlan]

Interesting and well presented, thanks

[@recursive_dream]

What a fantastic video, thank you!

[@Pollys13a]

Very interesting, thanks very much.

[@shalffon]

Thank you so much for sharing! 🙏🏻

[@7karlheinz]

Glad to see Howard Armstrong mentioned!!!

[@Kathy_Loves_Physics]

Armstrong is amazing and I mention him a lot

[@r.melihsengil8022]

Thanks. Good research.

[@youtubasoarus]

Fantastic presentation! :)

[@Kathy_Loves_Physics]

youtubasoarus so glad you liked it.

[@konaguzzi1]

@KathyLovesPhysics&History I've only just seen your channel this is the first video I've watched (youtube suggestion) I wish I'd seen it when you first put it up, thank you for your great content.

[@gnarfgnarf4004]

Congratulations, great video. When you say Edison noticed when the light bulb broke, there is the sound of glass shattering in the audio. This is misleading, it implies the glass broke, when in fact the glass does not break, it is the filament that breaks. Just a bit confusing.

[@majorseventh2699]

Excellent...great teaching...i just love useful science.

[@Moletrouser]

07:40 - An important point about grid voltage: valve circuits are designed so that the grid voltage is _never_ positive with respect to the cathode; significant grid current stops the circuit from working and can destroy the valve. Maximum current through the triode occurs when the grid is at the same potential as the cathode - it is like a depletion-mode FET.

[@goodmaro]

Yes, you have to bias it to prevent its shorting out thru the grid as an extra anode, closer than the plate. However, there are "gun" style electron accelerators, and it's possible the early experimental grids -- we're calling them "grid" only in retrospect based on the most successful design -- could function as electron accelerators, diminishing the voltage drop while losing a negligible amount of current to the grid.

[@dailydoorsteprangoli9179]

Awesome video. Can you pls tell me what book did you refer for this history of transistors

[@vacuumelite2065]

Thank you. ♥️ I got all nostalgic. Time to get my oddball 'tubes' , transformers , inductors out and build another guitar amp. I'm going old skool and querky. NO : ECC83 or 12AX7 types permitted. NO : EL84, EL34, 6v6, 6L6. EVERY amp uses these! I'm excited. 😊😊

[@canuckprogressive.3435]

I built a guitar amp with the goal of using tubes not normally used there as well. It has 6dj8 tubes and uses one of them in cascode. Unfortunately I never had much luck learning to play.

[@vacuumelite2065]

@@canuckprogressive.3435 Ahaa.... E88CC is our Brit counterpart for 6dj8. I think they both like 130volts or less on the plate. Mu is a third of 12ax7. I am an old UK 70's punk... you don't need many chords to have a fun time. Good luck. 😊😊

[@iesomir]

In addition to learning physics, i am learning english, very good pronunciation for those who do not have english as their native language.

[@iaov]

Love these videos!!

[@tobystewart4403]

Very interesting, but I'm surprised you do not mention Irving Langmuir. He contributed a great deal to the understanding of charge in vacuum tubes.

[@Moletrouser]

You are so right to bring up Irving Langmuir, who was officially _too clever by three-quarters._ He made great contributions to the design of vacuum tubes and got himself a Nobel Prize for Chemistry in an unrelated field.

[@marianesimpliciano2766]

such a good video thank you

[@davidremillard4181]

Great vid and teaching skills...thanks

[@danielramirezcruz.2209]

Fantastic information very good work..l love it thanks for posting wonderful

[@joewoodchuck3824]

I grew up with tubes. I still like them for the fun of it.

[@chrisfuller1268]

Excellent video!

[@dlkline27]

Back in 1958 while at Scott AFB studying electronics, one subject was vacuum tubes and the elements thereof. One day the instructor started an impromptu verbal quiz by asking what a diode was, then a triode, etc. until he got to the heptode. We never heard of a heptode. After stumping everyone, the instructor stated, "That's a real gone frog." Hep toad; get it?

[@henryfeng6556]

The picture on the wall is a classic, it shows the General Radio 561 vacuum tube bridge

[@davewallace8219]

Please do a series on the u.s. proximity fuse, developed in ww11. It helped win the war.... its fascinating....thank you!

[@torugonza]

Hello Kathy ,. I wonder who made the first telephone headset in history...can you tell us, please ?. Tks. Very pleased to see your videos.

[@Kathy_Loves_Physics]

I just looked it up on Wikipedia, and they said it was patented in 1910 but it was used between 1906 and 1910 where they would put two receivers on a headband. Check out the wiki on Nathanial Baldwin.

[@torugonza]

@@Kathy_Loves_Physics ok tks so much. !

[@zachreyhelmberger894]

Wow! Great stuff!!

[@user-bubstech]

I love your videos and you have great knowledge in the earia I like to learn

[@mohabatkhanmalak1161]

Very interesting on how the vacuum tube came about and just like the atom theory and electricity, it was the work of several individuals spread over decades that brought it all together. But even today its amazing how they built devices like the radio, TV, radar etc . Kathy, are you a physicist, you have in depth knowledge of this science.

[@marcopilati7464]

great documents. Thanks.

[@Sam_on_YouTube]

I'm looking forward to the stories that are not well known about EPR. People generally know from Einstein through Bell. But not many know about the communications between Einstein and Bohm when Bohm was writing his QM textbook or Bell's response to Bohm, or the history of experimental confirmation from Aspect up to present day. And almost nobody knows about Kochen, Specker, or Conway and their revised versions. Or the weird definition of free will used in that theorem. Plus, Bell is just an interesting figure.

[@canuckprogressive.3435]

I made a few cool thing with vacuum tubes. They are really cool.

[@ki4dbk]

This is awesome. Watch Uncle Doug's History and anatomy of the Beam Tetrode. Also great.

[@alcoholic2412]

When I was a kid, you could take the tubes out of your radio or TV and take them to a drug store where they had machines that you could test them on to see if they were bad and needed to be replaced.

[@lrueff]

I actually have a printed advertisement for that service that was in drug stores

[@canuckprogressive.3435]

I know a vintage audio repair, sell, and trade store where they have a tube tester.

[@diegoochoa572]

Don't mean to be rude but was it really Edison that "discovered" all those interesting things about his Bulbs? Or was it his engineers?

[@Kathy_Loves_Physics]

Diego Ochoa That is not rude and honestly Edison has such a large factory of inventors by the late 1800s you never knew what came from him and what came from someone else. Considering how busy he was at the time, my guess would be that his engineer discovered it and that he decided that it was useful as a voltmeter and patented it.

[@dargall1]

Awesome video!

[@uber1337hakz]

Good video 😀

[@ghlscitel6714]

You totally forgot Robert von Lieben who invented an amplifier tube and was at court with de Forest for years about patent violations.

[@lawrencedoliveiro9104]

3:32 A liquid semiconductor (acid solution) to form an electrolytic diode.

[@ianuragaggarwal]

I have 10 tube radios and around 600 tubes in collection.