The Vacuum Tube Diode
January 7, 2026 • EPISODE 292
What invention helped spark the age of electronics? In this episode of Science LIVE, Dr. Roger Billings and the Protégés break down the vacuum tube diode—one of the earliest electronic components that made controlling the flow of electrons possible. Learn how this simple device works, why it was so important in early radios and computers, and how it laid the groundwork for modern electronic technology. Join us for a clear, engaging look at a key milestone in the history of electronics.
About DrB
Dr. Roger Billings is a visionary innovator whose work has touched the lives of millions of students and transformed the landscape of education. Widely known as “DrB” to the countless kids who benefit from his groundbreaking Acellus learning system, Dr. Billings has dedicated his life to advancing education through technology.
As part of DrB’s lifelong commitment to supporting education, Science LIVE was launched as a way to “give back” by mentoring students in conjunction with the Roger Billings Scholarship Program.
Read more about DrB »
About the Roger Billings Scholarship Program »
Happy New Year! I am excited to be back! I can’t pick, so I say both!
I can’t choose between David and Caleb 😭
I would have to pick both as well. I think science is just awesome and there is just so much to learn and do.
Dr. Billings, I like both Caleb and David! They are good together, so we should keep them both.
Dr. Tobias, I wonder how hard it was at first to translate the messages without paper.
Dr. John, maybe those robots could build more of the same type of robot on that micro scale?
How many drones are you thinking to deploy? I was thinking about having stations like police stations and fire departments
I would pick both of them to be honest. They’re both good candidates and great explainers.
David is number one for me.
I thought it was funny when R 51 made his son and grandson appear, it
made me laugh
I vote for both David and Caleb !
I vote for both, awesome episode!
I vote for both
wow those guys were awsome, great job !
I really like learning about electricity. I vote Caleb.
I vote for both! they are amazing!
Hi Mr Billings, my favorit book is Charlie and the Chocolate factory. I want to have a chocolate factory when I grow up. That is why I like seeing sciencelive, it is very interesting. Thank you! I vote for both.
david for the win
Happy New Year! I love Science Live videos. I never knew plants utilized water differently.
I vote for Caleb,very interesting video.
How long did it take Mr. Morse to design the Morse code?
I would vote for both David and Caleb!
I loved learning about the Edison Effect. I vote for both.
i vote for david
i vote for Caleb
i like acellus
I’m gonna have to vote for Caleb, I like the way he added humor to his video clip and as a 16 year old I still like to joke around. I also especially liked the way that he wants to turn his way from being a filmer to actually being on the other side of the camera and acting. Caleb is Amazing!
Im voting for david
David’s posture and facial expressions shows a lot more professionalism including the way he expresses his opinions and what he wants to say is very serious feeling while still being gentle and polite. He feels firm and confident with what he does. David is the best choice for my vote.
I vote for David, excellent information
I cant believe that we can make things so small!
I vote for David
I vote for both.
I vote for Caleb hands down
I’m voting for David. I missed science live!
I vote for caleb
I thought that the part where Tobias was talking about morris code was really interesting.
I vote for David.
I vote for David
I voted for both of them because I am sure they’re both doing something very good for the Acellus Academy!
I voted for both!
i vote for david. this episode was really good thank you!
i vote for David
I’m voting for Caleb, but both are awesome!
I vote for both
I vote both David & Caleb
David yes and Caleb yes👍
thanks for another great week of education, Doc!
I vote for david hes the best
R51 oh yeah
I liked this episode, and I vote David.
I vote that David and Caleb both do it. I like what they invented something to watch plants breathe. And I love Anastasia’s story! And I’m excited for AP English literature. I love the little robots!
always 100/100!
I enjoyed this episode. I vote for David.
I vote both
BOTH 👍🫶
I love the tiny robot!
LOVED this lesson!
I really admire doctor Billings
I vote for David and Caleb I like the thing they did
Caleb and David
I vote for both David and Caleb! You are all doing a stellar job!
I think both David and Caleb did a great job, but if I had to choose one I would vote for David.
I think Calab is a yes and David is a may be.
I vote for David! He is so smart and serious.
Anastasia’s invention was very impressive!
The lesson would be so much better if they both were in!
Happy New Year! I vote for both Caleb and David!
I really hope that we get to see more of David and Caleb. I really enjoy a good 30 second build montage!
This episode is amazing. They are both great but I voted for David 😂
nice to meet David and Caleb
i vote for Caleb!
I vote for both David and Caleb
Agreed! my vote is for david
I vote for David and Caleb
I love R-51in the science live, he’s so funny!
I gotta go with david, hes just the goat. This episode was amazing
Same bro
No Caleb
I can’t disagree he is the goat
I honestly vote for both.
I vote for David!!
I’m going to have to go with David but I love them both
I vote for both!!
Ohio ….voting for David
I vote for Caleb
Yes! Team Caleb Vote here!
I think Caleb too!! he’s just so funny!
I really liked this episode. I vote for David.
That was wonderful! I prefer David because he’s more serious (probably because he’s older;). I’m very excited for the new episode!
Hi from Utah! Thank you for the Science Live!
I love science and I personally am voting for both.
Both Daniel and Caleb are great! So happy we’ve made it to the new year and science life is back! Excited for the new English class!
Congrats to Anastasia! that is amazing!
I loved learning about the vacuum tube diode.
Honestly, I vote for both!!!!!
R-51 is so funny and makes my day honestly
My favorite part was when R51 was teaching the big R how to make a grandson with 2 batteries and a sunflower.
Thank you so much for these AMAZING lives!!! Hope everyone has a wonderful blessed year.
I rate this science live a 10/10
I vote for Caleb and David.
Does the microscopic robot swim on top of the surface of the water or under the surface of the water.
R51 is the best!!!!
Happy new year from Utah!
I think that Kalub should have their own film class.
love it! I vote for both
I vote for both of them. also plants breathing does not make sense
The painting Samual made of famous paintings is really cool !
I vote for David and Caleb, they make a good team and they are funny.
Great show today!!
I think both are great!
I vote for caleb
I live in Arkansas and tornado season is the WORST out here 🙁
Hi from Mississippi great show, I vote for both!
I didn’t know robots could be so small.
R51 is so funny everytime he comes on I start laughing
HAPPY NEW YEAR from Alabama!!!!!
Happy new year I vote for both
I cannot choose between these two guys, they’re both awesome.
I vote for David and also happy new years
Happy New Year. David and Caleb are funny
I loved this science live possibly one of my favorites!
Making a self portrait is pretty impressive.
I vote for both.
One of my favorite ones yet i love it!
Hi from Japan♡☀︎
my family is from japan too 🙂
Great news to hear about Anastasia’s success.
R51 is so funny, also Happy New Year from Georgia!
I liked the parts about Morse code. I thought that Caleb and David both did a good job.
i love roger billing its my fav part of the week
I love how Acellus is creating a new English program
one of my favorite lives yet!!
i love roger billings i learn sm every week
Let’s get this party started!!!!!!
I love science live it’s the best.
It is hard because I like both of them. Probably Caleb I also like David too. Happy Late New Years!
daviiiiiiid!!!!!!!
they are both so good.
I love SCIENCE!!!!!!
👍👍👍👍👍👍👍
I think it is crazy that robots are getting smarter but smaller.
R51 is my favorite. I love the tiny robot. I vote for David!
You can definitely tell where Caleb gets his sense of humor from haha. I vote for both Caleb and David!
First science live down, and I vote for Caleb !!!
Happy New Year! also i vote for David & Caleb.
Happy birthday Dr. Billings
Yay science live!
I’m so glad that both David and Caleb will be teaching us more.
Happy New years, I vote for Caleb.
WOW!
It was thrilling to see Roger Billings son, and it’s very interesting that robot’s can get so small. Someone should make a army of tiny robots.
Science live teaches me something new every episode.
Happy late new year, hope it brings good luck!
How amazing is it that Dr. Billings has a son just as smart as he is?! I vote both gentlemen, they both seem to be headed in a an awesome direction to a very bright future. Congratulations to Anastasia, just WOW!
Science live is the best!
I vote david, and happy late new year! I loved this Science LIVE by the way.
Happy new year y’all!
how deep can the tiny robots swim around in water and would they be able to swim around in the ocean?
David and Caleb definitely!
Happy new year everyone!!! 🎉🎉🎉 I really liked this science live! My favorite part was when Caleb and David explained vacuum tube diodes also the 30 sec build montage was funny! the ☕ break was funny
I think that this science live was incredible.
This Science Live was my favorite! 100% both CALEB & DAVID!!!!
Thank you Acellus team! David and Caleb were both great, and I loved how genuine their relationship was. Also it was so neat learning about morse code, I think it is so fascinating how it works! I make morse code bracelets with encrypted messages on them for my friends and family! Looking forward to next week!
I love reading books!
I vote for both, David and Caleb😍
I love watching these!
It’s very interesting to see how the vacuum diode has changed over the years.
This science live was fascinating plants breath yes we know that but you explained how and why :D.
Happy New Year. I didn’t know plants breathed either.
science live is so fun to watch!
100% CALEB & DAVID FOR THE WIN!!!
I vote for Caleb & David I also try to play the guitar.
Greetings from Kennewick, Wa!
Happy New Years! Can’t wait to enter 2026 with Acellus and learn so many new things! 🙂
(btw, loved the science live today!)
Happy New Year! Good job Caleb and David!
Excellent science live to start of 2026, I look forward to all of the inventions that will be shown in these upcoming science lives.
I love r.51 he is so funny I love the videos
It’s crazy how planets breathe!
How do those tiny robots swim?
Dr. Tobias is so silly and inspiring, he’s my favorite! I loved the montages of Caleb and David, they are very charming and definitely have what it takes! (I’m expecting to see Caleb in a TV Show 🙂 )
I vote for david
Happy New Year from Kentucky!
Happy New Year from Wyoming!
Watching this got me inspired.
I choose David and Caleb! Hi from IL – Kimry
What is the process that will enable these plants to use water more efficiently? Also, with this new development, what else can we change about these plants to make them more efficient?
Its crazy how it is 2026 already.
what’s the most difficult situation you’ve ever been in roger?