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 »
I vote for both David and Caleb because I can’t decide between either of them
Learning about the tiny robots and how Morris code was invented was very interesting. I really liked David and Caleb and how they made learning fun.
I vote for David, i really like this episode.
I believe that robot is the smallest I’ve ever seen! I also vote to keep David & Caleb, they were great! I love watching Science Live!
I vote for both!
I vote for David but caleb has my vote to
it motivated me a lot .
Vote Caleb.
I have to go with Devid he’s lowkey the goat
I vote for Both Caleb and David.
happy new year! I’m voting for both!
It’s amazing to see how small computer chips and robots can get.
i would love to see that hydrogen powered drone.
The tiny robot was very impressive!
David is my pick due to the fact that he has potential dad energy and seems to be already heading in the right direction of being a good influence towards the community
I vote for both of them!
Hi!! Great video. Thanks for the winter break! I honestly like both David and Caleb. I don’t think I could pick one or the other!
I gotta go with both!
They would make a great duo!
Congratulations to Anastasia! her idea sounds pretty cool to me, and i’ve always been invested in tornados and natural disasters, so whenever they do finish the product, i cant wait to see how it comes out! i always give both David and Caleb my vote!
It’s nice to be back to watching these videos! I really missed these!!
I vote Caleb!
I vote for David
David and Caleb yes yes yes!! — Just don’t step down. (just not to much at least.)
I think the tiny robot was interesting and thought it was amazing that Morris was an artist before an inventor, because I also love art. I think Rodger’s kid and grand kid were very good but I don’t want Roger to leave because we would all miss him.
I vote for Caleb
Tobias’ sections are my favorite.
Vote David. Good episode
The morse code story was so cool! I always wondered why the pattern for what letters got what combinations was so random.
I vote for Caleb, I liked his perspective more.
Vote for David 100 percent
Science live is sooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo good 👏👏👍👍👍
I think I prefer David! Hard choice though!
Caleb
That was really fun and educational. That mini robot was so cool :0
:)A :)M :)A :)Z:)I:)N:)G:) 🙂
How does blood circulate
love this show!!
I definitley would vote for both honestly they are both the goat
I vote for Both David and Caleb
I vote for both
I vote for both!
I VOTE FOR BOTH!!!!
Hi from Texas! Thank you for the Science Live!
I vote for Caleb! 👍🏻
The vacuum tube diode was very interesting to learn about. I’m so happy Science Live is back!
I vote for David cuz he’s the BEST!!!
I vote both
How did they find out about positive and negative?
Honestly, I vote for both!
love you guys. Calbe and David did a really good job
I vote both to be honest
Definitely voting for Caleb!
I vote for David he did amazing
I vote both!
I vote both I hope everyone had a nice break
I vote for both son and grandson. They make a great team!
This was my first week of online school and my first Science Live. That was fun. I vote David
I vote for both I had fun watching this with my sister
We vote Caleb
This was a wonderful Science Live! It’s a very close race, but I have to vote for David on this one.
Caleb is my goat gotta vote for him!
I vote for both!
I ❤️ science live!
How do you fly a drone in a tornado? Won’t it just be thrown around.
I liked both David and Caleb.
I honestly liked both David and Caleb as candidates. They both possess different assets that could complement each other if utilized together. I liked learning a bit about each of them personally. Good luck to them both!!
I like caleb the most he’s incredible.
I vote for David
Great teamwork. I also loved learning about morse code.
David and Caleb make a great team.
I honestly vote for both . I really liked this episode . Can’t wait to learn more stuff . Learn something new every day
Comment I liked Caleb and David. I liked the vaccum tube diodes, how interesting. And how about Dr Billings sons just as smart as he is. Absolutely amazing!!!
I vote for both David and Caleb
This is amazing ✨
I agree.
Can vaccuum tubes be used to harvest hydrogen somehow?
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
I vote for both!!
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
David has my vote . Amazing live!
I vote for Caleb
Both!
Yes! Team Caleb Vote here!
I’m trying to be in a band to! Speaking from CT.
I think Caleb too!! he’s just so funny!
I voted for Caleb and David they were both amazing
I really liked this episode. I vote for David.
This episode was probably my favorite so far. I gotta go with Caleb!
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?