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 »



They keep getting smaller and smaller and faster faster!!
It was really cool seeing David and Kaleb
Wow, that vaccum is really cool!
This science live was so interesting!
I love to see plants breathe. That would be so cool.
This one was great.
This video I really enjoyed watching and learning from it.
Happy New Year!
I love science!!!!
If plants did not breathe would they die?
Thank you so much for this video!!! I loved it so much it was really good!!!
wow, before this i was clueless about the flow of electrons
I missed watching these over Christmas! So much good info!
Great science live, cool to think about the possibility of hybrid plants.
Very interesting to see how a painter Samuel Morse can invent the morse code to send information miles away. Thank you for your teaching.
Keep both David and Caleb…They are great!
I like Dr. Tobias’s way of teaching. Very easy to understand. It was very interesting to see Samuel Morse’s painting and how the morse code was invented.
I was expecting this topic not be engaging for me, but now, after watching it a week later i’m about to go do a ton of research because I got fascinated.
I think morse code would be cool to learn. The way it has been used throughout the years is numerous. Is it still used a lot today or has it died off?
That is so cool how people can come up with and create a tiny robot like that!
I enjoyed this video
I loved learning about morse code!
Computers are amazing
In the very beginning of the video, I thought the part about the weather device was interesting.
What kind of metal do you need to make an electro magnet?
I have used morse code sometimes, but rarely, I think everyone should know it or be familiar with it.
Awesome about watching the plants breathe! Love how these videos start with a joke.
It’s so amazing that Bill Lear was your mentor!
Nice mix of science and Technology
Thank you, love this science live!
Morse code sounds extreamly cool!
Great episode! I really liked learning about how the telegraph was invented. Dr B and the Proteges were great to watch!
how do plants breathe in c02?
It’s pretty insane that some people could interpret morse code fast enough to read 60 words per minute.
I loved learning about the solar powered microscopic robots!!
These always make my day better!!!
Nanotechnology has a lot of uses, what was the specific purpose of the nano bots shown in the episode today?
Very intriguing!!!!!
Thank you acellus!,
“science is the search for truth” goes pretty hard ngl.
cant wait for next week !!
It always amazes me how small computer parts get.
I’m grateful thank you
I liked the tiny robot! Thank you.
These are getting more interesting every week!
David and Caleb work so well together!
I forgot to comment earlier when I watched the video! Welcome back from the break!
I love these videos, please keep putting them out!!
Science live is always so fun.
This one was actually really interesting! Technology is so interesting
I love science live
how does Nanotech work?
I love Acellus!
computers are cool
Didn’t realize this was the first live of 2026!
I love plants and would love to see them breathe in depth!
I love how interesting computers are
Technology is so cool. It would be neat to make my own robot.
How small can computers get
Hi from Texas.
Very interesting that a small robot can cost 1 cent to make and be used in medicine!
Morse code is so cool!
HI I loved learning about the vacuum tube diode thanks for sharing
I like that the smallest robot in the world can swim
The video was great, had a lot of useful information.
first live of the year!
This was my favorite science live yet!
Amazing how far communication has gone
Watching from Wi!
I love learning about inventions!
Such a fun live!
Dr. BILLINGS teaches such interesting topics!
that’s really cool how you can increase the volume with just a vacuum tube
Just came from January 8th’s live! I came back to say how cool these lives are!
i love learning tech everyday!
Are amplifiers can be used as musical or vocal recording?
Thank you for the work you guys put in!
This video was very interesting!
This was such an amazing video!! It had so many interesting things that i never knew in it.
Watched with my brother tonight. We both really liked the drone part.
I thought this video was interesting and I really enjoyed watching it.
hello from ga
I liked the drones and robots. I got a drone for Christmas!
First live of 2026!! happy new year
hi Roger billlings
Love computer tech so much!!!!!!
computers are always so awesome!!!!
the tornado thing was cool
Both David and Caleb 🙌🏽
I learned that plants breath carbon dioxide
Science is amazing
R-51 was so funny and today
Love these all the time I always learn something new
You could use these little robots to look at peoples insides, and people can just poop them out When needed.
it was very enjoyable and can’t wait to meet the new people
Science live is great !
Who invented the first robot?
I think that the way they explained how things came to be was more enjoyable because not only did they explain in a very clear and easy to understand way, but they also added some humor and little scenes that made the whole video more entertaining.
Hi Florida What are we learning about
I loved learning about Morse code how it was developed and the steps leading up to it.
I really enjoyed the lecture! Thank you and see you next week!
watcing from Middleburg, FL
I enjoyed learning about the vacuum tube diode
How does the Carbon fiber body armor protect people?
incredible video guy!!
Hello from Connecticut.
Hello from SC! This was cool.
The drones are cool!
I love learning new things!
Although I always enjoy science live, I heard through Acellus social media we we’ll be getting more updated live Wednesday Science Live, I am wondering when?
David and Caleb Together
Hello from Mississippi I appreciate the amazing videos
Amazing video, loved it!
I really enjoyed this video
It’s so amazing how computers can be created to be so miniature and still work properly.
I enjoyed this live stream, I learned a lot.
Tiny robots are so cool!!!
It’s amazing to see how they used to control the flow of electricity before transistors.
computers are always so interesting
Yes they are.
I am really surprised that the world’s smallest computer can swim.
I am also really surprised that it actually works.
It is cool that it is solar powered.
I am also surprised that it doesn’t break at the smallest ripple.
Do you guys sometimes record the science lives at home? Or is it always at the Acellus station?
Hi
LOL I LOVE SCIENCE LIVE
Caleb!
Hello from Virginia!
David and Caleb together
They make it so easy to love science
Exactly
Hi guys science live time
Happy New Year!
Interesting, I didn’t know David & Caleb were his son & grandson
I thought this video was interesting and I really enjoyed watching it.
Got to love technology!
Me too
I was wondering how big is the largest computer ever made and what is it?
loved the first live of the year!
I love tech!
Watched the other day and I can’t believe it’s the beginning of the year and the first live of the year!
A robot smaller than a grain of salt is astonishing! The fact that it can swim is even more impressive at that size! I imagined it would look like a little bug, haha but it’s just a basic design for now!
Nice video
It’s so cool how they made such a little robot.
Today was different for me and I learned alot with the LIVE.
This is so amazing
I love this!
This is one of the cooler science lives I’ve seen
Science live is my favorite thing to watch!
Hola desde Bridgeport 🖐️
Great first video for the year!
How do they make the robots so small?
I love Science Live! Thank you for all the work you put into this!!! 🙂
Great video, i loved the technology and science, both of them are great i would choose both of them.
I know so fun
Hi from Nevada!
I liked David and Kaleb’s explanation! Hard to choose.
I really enjoy the tech segments!
Morse code seems cool maybe il try to learn it.
Who invented the vacuum tube?
*who discovered the telephone?
I loved this so much!!!
Love the tech lessons
Love Acellus especially Science.
This was such a amazing live
This was such a cool live
What Is the largest robot ever made, I heard of one being made sounds cool.
I love Drones!!
How did they figure out how and what to code the first ever drone?
How did they get the air out of light bulbs when the first light bulb prototypes were being made?
Hello from Alaska!
I am currently becoming a volunteer firefighter, love the lives tho!
Drones are pretty cool!
The microscopic robot is surprisingly fast for it’s size.
Will David teach a class and can you tell us how AI makes pictures?
The tornado detectors are really useful, are there any other inventions being worked on that detect natural disasters?
Science is Awesome! hey from tn!
what was the thought behind making the vacuum?
I love science live is so fun
hi from missouri
This episode was so cool to watch, also, R51 never fails to be fun!
go acellus
WOW I just learned about the Vacuum Tubes at a Science Event I was at but you went into more detail about it. Thank you!!
what is the smallest computer ever made?
The tornado detectors are really important, is there any other inventions coming up that’ll detect natural disasters?
people need school and need to focus so they can get the career they want.
What is the smallest computer ever made?
Hi From Spokane
Very exciting new things coming 2026!
How long does it take to prepare a Science Live video?
I love science live!
Morse code is so cool and creative.