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 love these videos
david is so smart
Roger Billings is my favorite!
That is pretty cool about the diffrent sun screen that looks way better.
I love science Live!
I think its cool that robots are smaller than a grain of salt.
One penny for a robot. Very interesting. I like robots.
how is it that the other people on the receiving end of morse code can read it so fast
Science Live, rewatching it after traveling.
I love science live!!!!
Electronics amazes me how far along they have come.
I didn’t know Samuel Morse was an artist. Very cool.
I am working on something that i might bring to the science fair and it uses water to make eletristy
what place did you get science fair
Hi from Tennessee
I love science live great episode.
I love this, thanks for all of your effort to do these videos!!
I learnd how a computers are made
I really enjoyed this lesson. Learned a lot of new information.
Hello from South Dakota! New to Acellus!
Thank you. Love science
I found the part discussing NASA interesting.
Computers are interesting.
The talk about morse code was very interesting, I’ll learn it sooner or later!
I enjoyed this ‘preciate the info about plants being able to breathe. 😉
Hello from Georgia! Caleb and David were both great at explaining the Edison effect and vacuum tube diode! They both work really great as a team! Love the sense of humor too Lol
theres videos never fail to amaze me always so interesting!
This is very interesting. I am always eager to learn new things.
I love learning Science. So Awesome.
The awesome thing about Asellus is a million things. it’s AWESOME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I enjoy these videos quite a bit.
Very cool first video of the year!
how do they give the robot a program when it is so small
Caleb was the best candidate, definitely my favorite. (Tobias is better though)
I liked Caleb, I didn’t know Morse code was on paper first, amazing episodes always now with extra wow 😀
I liked Caleb and David’s part!
I liked it very much especialy when they talked about the vacuum tube diode
It would be so cool to see robots making stuff
First video of the year!
Amazing how far communication has come along.
The vacuum tube diode is so cool 😎!
I learned a lot
Thank you for the videos!
It would be awful if a tiny robot was in the bathroom with a camera! I vote Caleb
R51 is funny with the flower and battery.
Cool how robots can know where is cold and where is warm
How can you make robots as small as salt? How old are David and Caleb? I vote Caleb.
That is amazing how tiny robots can be!
Im learning about electrons in scienece
another great live I loved it cant wait for next weeks
Both David and Caleb
Nano tech is cool!
Its pretty amazing what that they can even control electrons
Science live is awesome
How does the robot turn in water while being so small.
Ooohh this one was very interesting!!
i choose both
Loved this episode!
I liked learning about Morse Code.
I love morse code even more!
I’ve never learned so much about morse code!
Dr. Billings is the best!
What did Sameul Morse’s first painting look like?
ive always liked morris code and want to learn how to do it… thanks for an awesome lesson
I loved the first science live of the year!
this was so cool love these
I like watching science live
hello from texas
Nice episode, I enjoyed it.
I liked learning how the vacuum tube diode made it possible to control the flow of electrons and why that was such a breakthrough for early electronics. It really helped put into perspective how radios and early computers worked and how those simple ideas led to the technology we rely on today!!!
Are nanowatts the same as nanoparticles?
Thank you for the time off. Welcome back, great to see R51
that’s crazy how that small of a robot can swim
I hope everyone had a great break! I am ready to start learning again and excited for these science lives!
how can they make robots so so small?
Thank you for the time off for the Holidays.
I never realized how small technology could be!
I think it’s very cool how robots are so evolved.
The concept of creating new, more efficient hybrid plants is so fascinating!
Love your AP classes!
Love science lives!!
It’s amazing how science works its magic.
SCIENCE LIVE IS THE BEST
I really like the morse code story.
It is so interesting to learn about!!!!!!!!!❤️💕
FIRST EPISOD OF THE YEAR!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
carbon nanotubes are awesome! but if you use one that goes all the way to space, what if the motor breaks or the cable breaks? is there a such thing as hydrogen trains or hydrogen steam trains? Maybe I can invent the hydrogen train!
Hard to choose which one I like better. Hope to see them again soon.
Great first science Live for the New Year!
hello from Michigan
Morse code is very interesting how it works
This episode was very enjoyable!
I vote David and Caleb!
What a great topic! How do you all decide what your topics are going to be each week? Can the students submit ideas or vote?
I liked both explanations keep them both.
Love these videos.
I had a great Christmas break! Now I am ready to learn more!
I would love to build my own computer
I like learning about light bulbs. I also would like to learn more about filming and film editing.
Ireally liked Caleb and David
Hello from Florida
Great episode! I’ve always found morse code very interesting and to get a segment about it is awesome!
I never knew much about the history or invention of Morse code, so it was really interesting to learn about. I also never realized what an impact it had on revolutionizing technology.
How does increasing carbon dioxide concentration affect Earth’s average global temperature over time?
I loved learning more about morse code.
Loved the Live today, the cardboard was funny lol
This was so neat with the Telegraph and how they did the language back then. So amazed at how far technology has came in the years.
It is amazing how small a robot can be made!
The new Literature and Composition class sounds fun!
The smallest robot was so cool!
David Billings is awesome, so smart! First time I’ve seen the world’s smallest robot in your finger tips. Great video!
Hi from Illinois
I would say such concepts need to be further explained to fully grasp their essence
Hi i’m here from Japan
can size of the robot effect how it processes like for example if the robot is as big as a bottle of water can that effect the performance of the robot? or will it still operate the same way as the robot you discussed in this science live?
Wow! We didn’t know that robots could be so small.
This was so interesting!
David is your son and Caleb is your grandson. How cool to have them on the show! They love science too!
David and Caleb working together.
Who made the first vacuum tube?
I really liked this live!
I loved this science live!!!
Best science live yet!
I’m starting high School soon
Technology is a vast and interesting subjecr, happy (late) new years
This was cool to learn about!
What a interesting science live, I learned so much!
I find it interesting that carbon nano tubes get grown in a really hot oven, and they can be used to make space elevators. That would be crazy!
Love this for the first video of the year
I love science. It makes everything more fun
thanks for doing science live today!!!
computers are amazing and very cool how tech exist
How many of the smallest robots can be made in 30 minutes?
Mr billing’s has a son!? I really liked both the videos the boys made-
I learned a lot today! (Also I think Caleb’s the favorite.. 🤪)
How do they make carbon atom tubes?
I liked the video! It was really interesting, definitely the part with the tiny robot, so impressive that such a small robot can swim.
Love it, i found it very interesting that a tiny robot can do those things.
Science live brings me so much joy when I watch it
I love area 51, he is so funny.
The code segment was great
Great episode to connect history and science
Dr. Billings that was a good idea to accept that and I think you do a good job teaching science live. So do you lady pay jet
I want to be a scientist when I grow up!
Replayed
Very cool science live! My brother just got a guitar and he loves playing it!
This science live was really cool
This episode was very interesting! I enjoyed it a lot!
Love the video so interesting.
Dude, this was awesome. Thank for the dive into how this works; it;s incredible the amount of inventions that could stem from this.
What was the reason morse code was made?
What are common ways the vacuum tube is still used today and how has it been improved upon?
I love learning about commputers
This was a cool episode!
Happy New Year Acellus! How do hydrogen cars use hydrogen to make energy?
When can I sign up for AP English and Literature courses?
I just started acellus! This was my first time watching
I can’t wait to sign up for AP English and literature in the future. Thanks Acellus!
phones are very cool
R-51 is the best.
the sun????🌻
🤣
how do they make robots so small
Always good to be here.
Science lives never failed to teach me something new
Science is so interesting and awesome
this video was really interesting and I really enjoyed it. Science lives are so fun.
calub!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Hi! Ariadne here. So loving the idea of the Science Fair! I think you should call it Science Live Fair. Super excited!!! Hoping making music counts as a skill 🙂 I know David and Caleb said that would be ok
It’s so cool that the solar plates can detect light to know when to charge!
Why is it called vacuum?
love learning about computers!
I like this episode. It shows how science may be involved in doing other things and not just inventions.
i vote for both
Hello from Florida! =)
It is amazing how technology has evolved over time! What is the biggest computer ever made? Did it work the way computers do now?
Science is my favorite subject!
Love the video cant wait to learn more!!!!
What other abilities are people planning to add to the tiny robots?