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 2026! Amazing Science Live video!
R51 is the best.
Do they still use morse code that often today?
Today I learned what a vacume tube diode is. Also that no matter what you are good at you can always learn something new.
wow roger billings is so inspiring
I like when there is history in science live! I like both Caleb and David.
I love this so so much!!!💕
Loving Science Live!
I think as the years goes by the robots will be more advance and doing more things for humans.
I voted for Caleb I love cameras and I have always wanted to be an Acter, and I love editing I edit literally every day. 😀😃😄😁😆☺️😊🙂🙃😉😌😛😝😜
I love science live can’t wait for next week.
I really enjoyed learning how the Morris code was invented. The tiny robots were neat as well. Most of all I liked meeting David and Caleb. Caleb needs to teach us how to play the guitar!
How did Samuel moore creat morse code? I vote for both david & caleb!
This is my first live! I didn’t know plants breathe, but now I do!
My name is timothy and i wonder will we learn more about hydrogen or are those episodes over?
I liked when they were talking about the tiny robot.
Happy New Year Science live!! I voted for both Caleb & David! I love Science Live!!
Great video! I vote for David!
I vote for Caleb and David
I want a tiny robot now!
Happy New Year! I vote yes to both David and Caleb.
Its amazing how they were able to make a robot so small!
Plants are so important to our enviornment!
Two bright minds = Two votes ( David and Caleb)
I really like how every episode it shows a student achieving there goals. Go Anastasia
I pick both! Happy New Year!
I like both of them its hard to choose so i’m going to say both
Happy new year! I vote for both
They make a good duo.
I actually have to vote for both of them.
I like this because this teaches a lot facts I didn’t know.
Happy New year! Science lives on!
I love science live!!!!
Awesome science live as always! Caleb AND David 🙂
Happy new years everyone! its been a great year so far!
This is the greatest show
This live was just great, loved it all.
I vote for Caleb and David! also happy new years again!
Welcome back.
Happy Belated New Year Science Live! I vote for both David & Caleb!
Happy late New Year! It’s surprising that people can make robots so small.
I really enjoyed this Science Live. I would like to see them both because they’re both funny.
I really like Science L!VE. I knew that plants do breathe through holes called stomata, but I didn’t know that Samuel Morse was a really good artist .
I LOVE SCIENCE LIVE AND A HAPPY NEW YEAR!!!
David and Caleb. The video was very funny and they both explained the process very well. 🙂
I loved this episode!
Happy new year!!!! I vote for David
Learning how morse code works was amazing and I vote for Caleb
Happy new years Science live, can’t believe it’s already 2026!
didnt know you could predict tornados forming. so cool!
Happy new year from France
I THINK BOTH
I can’t decide….. I choose them both Caleb and David!!
Welcome back, y’all! Happy 2026!
Anastasia’s story is inspiring. I love how she knew her dream and reached for it, and is using it to help people.
I really love both of them, but I’m going to vote for Caleb. Happy New Year from Kentucky!
It would be really cool to do something for NASA!
I vote for both!!!!!
Happy new years! This science live was amazing I can’t wait for next week science live. I love learning new things and I enjoy watching all the interesting information that science lives bring.
David for the win.
I love the jokes from science live!!
🔥🔥🔥
Todd Edmond is my favorite teacher
I always love R51, he is so funny.
i vote 1 for both David & Caleb!
I think that the worlds smallest robot is really cool because it can swim and it can be reprogrammed with flashing lights. I wonder how long it took to make Morse code? I liked meeting David and Caleb today.
Caleb’s segment was pretty entertaining but David was close
🩷 science 🧬
Plants breath that’s so cool.
Acellus is the best
I vote for Caleb and david both
Eli here watching from Ohio
Also I almost forgot to wish you guys a great new year so here ya go. Happy new year and I hope you fulfill your new year’s resolutions.
Thank you for the video. It was very interesting. David and Caleb were really exciting . I didn’t that plants breathe carbon dioxide.
If Dc current is better in most scenarios then AC what is AC used for?
i choose caleb
My vote is for David!
It was cool to know that wrapping a metal and giving it an electric current can turn it into an electromagnet!
Happy New Year!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Happy New Years! The left foot joke was a good one, happy to be starting my new year trying a different schooling method!!
Another great science live, I always love watching.
Happy late New Year to everyone in Science Live!
GEORGIA, TEXAS, monitoring a tornado is cool and i misses this, happy new years.
I’m still shocked planets breathe.
I love science live, I voted for David, I did not know if you could vote for two people or not.
I vote for David and Caleb!
I vote for David and Caleb. THEY ARE GREAT!
Today’s lesson was pretty good! I vote David and Caleb.
I thought it was cool that the smallest robot is the size of a grain of salt.
R51 did it
Happy late New Years! I vote for Caleb!
This Science Live was so interesting!
This was so fun to watch! Thank you Acellus!
merry Christmas and a happy new year everyone.
I vote for both david and Caleb.
Best part of my week!
So cool! Enjoyed watching this one
I love science live !!
Congrats to both David and Caleb amazing
Science live is hecking awesome!
Congratulations on the new AP and literature course! It was really cool hearing more about Morse Code history. That was a great video about David and Caleb and how they solve problems. Happy New Year!
Happy New Year to everyone at the Science lives!
I vote for David ! Happy New Year!!! Great live !
It’s cool how plants breathe carbon dioxide and not oxygen.
The possibilities are almost endless with theses robots when become advanced.
I think its crazy that the smallest robot in the world can do so much, while being smaller than a grain of salt.
Vote for both!
i love drones! it’s interesting how they use them to keep people safe from tornadoes!! 😀
It’s incredible how engineers can create microscopic robots, SMALLER THAN A GRAIN OF SALT! I vote yes for David and Caleb. Great demonstration of AC and DC current.
This live was very fun to watch, and I learned a lot of cool new facts.
this was very interesting r51 having a son and a grandson was so funny
cant decide they are both so funny though!
Absolutely both David and Caleb!
i vote for david and caleb!!!
Caleb
Science live was great and even more educational. I’m excited to be back, and happy belated new year!
Caleb has the coolest job. I hope he gets to become an actor!!
i love that drones keep people safe from tornados
I vote for David and Caleb!
I thought both David and Caleb were very entertaining to watch but I vote Caleb because he was hilarious.
David and Caleb both seem really cool. I would like to see them both come back if possible. Also Happy New Year!
Thank you for explaining HOW the dots and dits of Morse Code were assigned! I always wondered!
greetings from wyoming. thanks for the live
I really enjoyed the latest edition of science live. I vote for both David and Caleb.
I’m just amazed at the fact that Fleming worked for both Edison and Marconi, and was the person who used the Edison effect to create the first Vacuum Diode.
Both Caleb and David I like. but Caleb I like more.
Happy New Year! I love hunting too!
David and Caleb!
I vote for both
I don’t think I am a good enough listener to have been an operator for Morse code!
Always love tuning in.
I liked them BOTH. They explained it so well and, they made it interesting too. I have only been in Acellus for a week but, I LOVE IT SO MUCH !!!!! Reply if you love it !!!
I love science live stay blessed, David was super funny
its really cool how they take the time to give us so much knowledge about various topics
I liked learning about how plants breathe through their leaves because they have tiny holes. They breathe in carbon dioxide and breathe out oxygen.
My favorite quote from this episode: “Here at Acellus, we’re having a lot of fun!” So true and I tell my friends this all the time.
I am also learning how to play the guitar.
Love this one! Hello from Florida!
Happy belated New Year!
Wow! This was very encouraging for students who don’t believe they can be inventors!
I vote for David and Caleb good luck to both!
They are both very good, but I have to go with Caleb.
I learned so much from this and it was such a great start to the new year thank you.
I can’t pick between caleb or David
I enjoyed watching the video that David and Caleb made.
WAIT A MINUTE R-51 HAS KIDS NOW!?
Happy New Year! I would probably vote for David.
Thank you Dr. Billings
Happy New years I enjoyed todays live! Vote for Both David & Caleb!
Both are amazing… but I will go with David.
I Love this science Live and I vote for David &Caleb
Happy new year!!!!!!!!!🎊
Both are good but I think David!
They’re both wonderful candidates. I would but both if I was able to but Caleb seems better.
I loooooooooove robots!
This video was so interesting and educational! I love it!
They are both wonderful candidates, but I think I would choose Caleb over David. They make a good team though. If I was able to, I would vote both.
That is cool how a robot can be that small but how is it classified as a robot if it looks like a chip?
Loved the live! It is so hard to choose who to vote for! I really liked both of them!
wow that’s crazy how much robots can do !
welcome everyone and welcome to a new year! And I’ve voted for david!!!!!!
I can’t believe it’s already 2026!!!
That drone looks so cool! Would love to see the statistics of the tornados when done
Happy new year!!!🎊
HAPPY NEW YEAR
Really liked this episode, that robot was SO tiny it’s crazy, and I think I would pick David but I do like them both
I liked how Dr. John was talking about the smallest robot that was ever created. Dr. John had also explained that this robot is so small it smaller than a gram of salt and that it can swim even though it’s size. Dr. John had also said that the hardest challenge was making sure to create it to swim since it’s such a tiny robot.
How did we discover brain waves?
This video was great! I vote David and Caleb! Also didn’t know that plants could breathe.
I love science weekly! I always look forward to it every week!
Hi from Canada, love the video.
I like David because he hunts and plays foot ball and i do the same as him.
I like how both Caleb and David work and i think they should be partners, so I voted both!
How did they make that robot so tiny?
HAPPY NEW YEAR! I can’t wait for the new AP LITERATURE AND COMPOSITION CLASS!!!! I hope ya’ll have a great day, and keep on working!
happy new years from Massachusetts hope you all had a good break
David and Caleb are funny!
Happy New Year! So glad Science Live is back!!!! Happy 2026 y’all!
Amazing Science Live! Happy new year!