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 david and caleb
Great episode! Love both guys are amazing!
My vote for David! Caleb is great too! Thank you for the class!
so cool I love acellus
I vote for David, but they were both great
👍David and 👍 Caleb
Happy new year!!
both got my vote
DAVIIIIIIIID
I vote for both.
I vote for both! Great video!
I love watching these Science is so cool!
caleb
Watched with my family
First science live!!! Happy new years!!!!
I vote for both David and Caleb.
I vote for both!!!!!!!!!
I want to be a engineer.
Great episode ! Loved the breakdown of the vacuum tube diode.
David go get them!! Show them who’s boss by winning!
great episode like always and David and Caleb both have potential like Caleb is funny and its always great to have someone who can bring some joy and all the stuff David does is amazing for people they are both very great.
I vote for both, they worked great together!
Caleb
I really liked this episode. I watched it with my parents.
For sure the favorite grandson
I vote for Caleb, and happy new year!
I missed science live so much I vote both.
I think that both are very good, so I vote for both!!
I think its crazy how much technology has shrunk in the last 100 years
i vote for david! amazing live cant wait for the next
It was a really good video
David got my vote!
It was interesting learning about the vacuum tube.
I voted for David
Enjoyed the first video of the new year.
I would vote for both but i liked davids presentation more
I vote for Caleb.
Happy New Year! I vote for both too.
I learned a lot thank you
BOTH!!!! They both have great humor and they are very funny. They explain things very well!
this is the best program
amazing stuff science live! I will vote for David!
I vote for David.
It was a really cool and funny video👍
The new AP class look exciting! I’ll be looking into that.
That robot is so small and it can do all that. wow!
I’m voting for both.
They are both great
I would vote for both but if I had to choose one of them I would choose David.
I VOTE FOR DAVID!!!!!!!!!!!!
I vote for David!
I vote Caleb.
I vote for caleb 🙂
It was interesting learning about the tiny robots that went in the water. I also like learning about high school courses.
I choose caleb
I vote david!!
Caleb yes
I really liked both David and Caleb
rooting for them both!
I vote for both of them.
I vote for both!
I vote for David! Great Job!
I love both but David for sure!
I liked microscopic robots
acellus rules!
I VOTE FOR BOTH!!!
I vote for Caleb
It hard to choose but I think David won my vote!
Hi, I really enjoyed this episode! I learned a lot about the Edison effect and about how to create a vacuum tube diode so that you can rectify a wave, using the Edison effect. Also, I vote both Caleb and David.
thank you, happy new year, i vote both caleb and david there both great. they both have different talents that would be awesome to combine. have a nice day!!
My vote is for sure on Caleb, happy new year!
I’m going with Caleb, his presentation was FIRE. and he just seems like a good person!
Hope everyone had a good holiday break!! Vote for David.
I agree with Claire, team David!! :):)
Both David and Caleb. Good luck! :3
I thought it was insane how a robot that tiny can be programmed to do such crazy things like swimming.
I like Caleb so much but David is so so funny.
I vote for David and Caleb!
Comment Team David all the way!!
I vote for Caleb!
I vote for David!! Both is a good choice though
it’s close but I gotta vote for Caleb!
i choose both. they are both great
Both. They are funny together like when they had a hard time sounding out names and when they were taking a coffee break. It was also so cool to learn about telegrams!
Does Acellus offer a course for cryptography
I vote both! They both cool🤩😎
I vote for David! It was so interesting finding out about the robot that is smaller than a grain of salt
I vote for both!
I have to agree with jonah. David is just the goat……
I vote for both David and Caleb
Go David!
I vote both!
i think Caleb did better, voting for Caleb.
I think David and Caleb are fire. Also, I’m low key obsessed with Morse code.
Me personally I will have to go with David on this one.
I vote for both David and Caleb
Hey from Indiana! I vote for Caleb he really funny but also smart at the same time. It’s a really cool balance.
David all the way.
Both of them were really good, I vote for both of them.
I find it so fascinating how one tiny robot costs only one penny each, I vote for Caleb even though there both amazing.
I vote for both!
we like David and Caleb!
I vote for david
I vote for both!!
I vote Caleb
We watched as a family, I cannot believe how small robots are getting.
HAPPY FRIDAY!!! these are funny!
They were both so good I don’t think i can even choose.
David has got to be my choice.
I chose David:) also I’m so glad we get to watch SCIENCE LIVE again
I vote for both
I VOTE FOR CALEB
Ahhh i vote for David.
I like how caleb represents us more creative minds, I like the balance it’s really nice. So definitely vote for caleb.
I enjoyed watching this and learning about morse code and how Samuel Morse designed it.
I vote for David!! And sorry I’m so late I’m been busy with family time!!!
Back from break and ready to go!!
This was a great live science, best way to start the new year!
I vote for David he’s tuff.
Honestly I vote for both.
I vote for both David and Caleb
I vote David he is cool
i vote for caleb
I vote for both, they’re both amazing!
I voted for Caleb he’s just to funny! And his episode almost made me cry!😭 (and laugh 😂)
i got to go with david.
I completely forgot about the telegram and it’s history, thank you for the recap! I vote for Caleb, personally he showed me that filming and editing might be a career I’d like to look into.
Positive and negative can equal something more.
I loved r51 and I vote both
I want to vote for both but I am gonna go with David.
Watching from Ohio!
I loved it so much!! i vote for caleb he’s the goat
I vote both!
I vote for David
When is the new History Class Conspirisy , myths, and mysteries going to be available???!!!!???? I REALLY REALLY want to take this course before i graduate and I only currently have 2 classes left before I can. PLEASE PLEASE PLEASE!!!!!!
This was a nice science live to start 2026. Aside from that I pick Caleb.
More Tobias please
My name is Rayden, I am from Louisiana. We watched together as a family.
Both got my vote!
My vote goes to David !
I vote for David!!!
me to!:)
This is really interesting! My vote goes to David!
I like both, but I vote David.
tooootally the favorite grandson .
Id vote for both but if I had to choose id vote for David.
to be honest i vote for both
I got to go for both of them, but more so David.
happy new year Dr roger billings :).
Happy new year. I’m glad science live is back.
My Votes For David hes amazing
Love this! cant wait for next week!
First science live of the year! Hoping to learn lots this year and accomplish a lot.
I vote for both! Hoping to learn so much more this year!
I also vote both David and Caleb.
Good presentation! I vote for David. Robert “R.J.” Still, 9th grade
i vote for caleb
🥳🥳🥳🥳🥳🥳🥳🥳🥳🥳🥳🥳🥳
I think they are both great
I think David and Caleb would be great for science live
david!!
yah I have to say both are perfect, I vote for David and Caleb
I vote for caleb
I feel like voting for Caleb because yes and I’m also exited for the new class. Good luck David and Caleb :3
Due both are great i choose both
I vote for David! I am excited for the new english class. It was really cool to learn about the robot that is smaller than a grain of salt.
I vote for David!!
Definitely both!
I vote for both
Team Caleb! Underrated pick but he’s on top. Science Live is AWESOME!!!
team David all the way
i say caleb
better then games
(From San Antonio, Texas)
Hello peers and comment viewers of Science Live! Today I thought both David and Caleb were did very well! When it comes to voting, you might want to vote both Caleb and David (which I really wanted to vote for both of them).
I voted for David, mainly because he wants to help online reputations. Too many people are targeted on computers, phones, and other social media downloadable devices. These inventions were made to help future generations… But too many people use it for wrong, so as soon as I heard his ambitions, I got excited that he wanted to help.
I loved this episode so much!
I vote for both!
I liked Dr. John was talking about robot that is very tiny. He also said that this robot is much smaller then a little piece of salt. Dr. John had also said that this robot can swim and the scientists had to make sure that they programmed it to work like that. He mention that this was the tiniest robot that was ever created.
Honestly I vote for both of them!!
I vote for David
Caleb
I learned there is a robot that is smaller than a grain of salt that swims and costs a penny.
I like David but Caleb is funny!
Mom note – Both explained the concepts very well and kept my son engaged the whole segment. Thanks!
Science is so COOL!!!!!
I vote for Caleb