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 liked them both. I vote for both!
I vote David!
I vote for David and Caleb because I like them both. I like how they demonstrated the Edison Effect and how the Vacuum Tube Diode works.
Loved watching both your son and grandson working together it’s inspirational. Vote for both
I vote for David💕
It’s super cool that Dr. Billings drove his OWN HYDROGEN POWERED CADILLAC SEVILLE. Coming from a car guy, that is extremely cool!
It’s amazing that Anastasia was able to do all of that. I vote Caleb.
I think both, David and Caleb, should be chosen to help with Science Live.
We liked David and Caleb’s presentations – they explained things very well.
I vote for both! I also can’t believe how tiny the smallest robot is! That is mind blowing 🤯
I vote for both David and Caleb.
I love Acellus! I hope everybody had a good break.
I like this episode of science live a lot!
me and my mom both vote for Caleb
this video was my favorite so far. thank you for all the work you guys put into each and everyone of our school work
Happy New Year, I vote for both.
Happy New Year! Great show.
LOVED THIS!!!
I vote for both Caleb and David!
Love this video! I vote for David!
Happy New Year’s everyone. Glad to be learning about these inventions and this history. These are getting more and more fun to watch.
I like that David hunts, I like hunting too
I loved it, and the jokes never fail to make me laugh. I vote for both btw!!
DAVID!!!!
I love science live!
What a good science live!
I WOULD LOVE TO LEARN MORE ABOUT PLANTS AND HOW THEY BREATH!
I vote both David and Caleb
I vote both. Great Video, lots of fun. Thank you Acellus and Science LIVE teams.
i vote for david
Happy new year! If I have to choose it would be Mr. Caleb, but both are better they explain stuff really well and are really funny, just like Tobias, and Mr Rogers.
Caleb yes! I liked learning AC/DC electricity
I vote for both. They each did great!
I voted for both!! 🙂
Thank you for the lecture as usual, I really enjoyed Dr.John’s lecture on that very small robot and what its capable of doing. Thank you for the wonderful lectures and I’m looking forward to see more in the future.
I vote for both of them! Happy New Year!
When we can vote, do the comments after science live get read or only the comments during science live?
Hard choice , I choose both!
Thank you Dr. Billings!
It was inspiring to hear about the girl that took the honors and AP classes and how successful she is doing in college with NASA.
I vote for both Caleb and David!!
This was one of the most exciting Science Live episodes yet! I vote Caleb and David. 😀
I vote for Caleb🔥🔥🔥
I vote both!!!
Both get my vote.
I voted david!!
Anastasia’s invention would be very neat! We live right beside PA and had a bad tornado!
I’m so excited for another year of Science Live. Also, I hope everyone enjoyed their holidays!
I’m voting for both Caleb and David they are both excellent presenters.
Thank you Dr. Billings!
Team Caleb
The drone sounds like it’ll be super useful!
I’m so excited about having another year of Science Live. Also, I hope everyone enjoyed their holidays!
I vote David. but both deserve respect and appreciation.
I’m so excited to be back to Science Live. Happy New Year everyone
Great video, very insightful. I learned to not give up even in difficult circumstances.
I vote for both!
I vote for both of them!!!
I love science live. I vote for both
I vote for Caleb.
I vote David!
I VOTE BOTH!
+1 vote for David!!!
I vote Caleb.
Hope everyone had fun holidays good to be back can’t wait for another fun year with Acellus academy and science live…
I vote for David..
i love Acellus !!!
Thank you for teaching me about how Samuel Morse created morse code. Also, I vote for David and Caleb.
We are also learning about plants in our fifth grade year!
Take AP classes to get ahead – noted.
Anastasia gives me determination to push through our curriculum and do amazing things just like she did with her hydrogen powered drone.
How is that robot so tiny?!
Morse code is both interesting and mind-blowing.
Caleb! Caleb!
Interesting video, thank you. My vote is for David.
That family is cool.
This was a fun episode of science live! Learning more about plants, the tiny and really cool robots, and about the telegraph was awesome. Both David and Caleb are good at explaining things.
Looking forward to the new AP English course!
Science live is making me want to go into robotics
Welcome back Roger B. I voted for David
I vote both. I think it would be cool if they both taught a class too. I would sign up for it. They explain things well.
I vote for Caleb!
I was wondering if Anastasias invention would work for blizzards and hurricanes? I vote Caleb.
I vote for both!
Vote for David
Hello from Texas, I also vote for caleb.
AHHH- I cant choose.. I vote both!
Both Caleb and David explained The vacuum tube diode perfectly.
I vote for Caleb. This was a very entertaining Science Live!
Both!
I voted David !
I VOTE CALEB 😀
Excited to watch the first Science Live of the New Year!!
I vote for David!
I vote for both! Watching from SC!!
Very intelligent young men we enjoyed watching them both.
I vote for both (hilarious!). I can tell that we will have a lot of fun with David and Caleb!
This weeks science live was very entertaining!!!!!!
I wonder how technology would have progressed if the vacuum tube diode was never invented.
We vote for both, David and Caleb! We look forward to seeing them again!
The Samuel Morse story is so interesting… 👀
It was so cool learning about the smallest robot! Also, I do not want to pick between the two guys! I like them both! They are so funny together and I learned a lot watching them.
I love how Samuel Morse created the Morse Code language by making the most commonly used letters the easiest to send, while the lesser used letters used more dots and dashes!
I am glad Science Live is back!
I vote both! It’s interesting how far technology has come.
These science lives are really fun to watch
It’s crazy to think of what robots could be capable of doing. You would really have to trust science to have faith in things if they were medical. Both David and Caleb have excellent views but I jived more with David.
voting for both!
Team David!!!!! Love the idea behind it !! David for the win.
It is a hard decision but I would say Caleb!
I vote for Caleb!
I vote for both David and Caleb! The two of them seemed to work very good with each other, and the explanation of the Edison Effect, vacuum tube diode, and rectifying was very well explained.
WOW yes both i loved it. I love the fact tht they enjoyed themselves
so yeah both it is.
I vote for both of them!!
The little robot reminded me of the Spy Kids movie I watched as a kid when the uncle had a supper small camera lol.
I’m just starting Acellus. I thought both David and Caleb explained things well and I liked the humor.
Morse code was developed as a method of encoding textual information into a series of dots and dashes, which could be transmitted over telegraph lines. The invention of Morse code revolutionized long-distance communication by enabling messages to be sent quickly and reliably across vast distances using electrical signals. The system assigns unique sequences of dots and dashes to each letter of the alphabet and numeral, allowing for efficient and clear transmission of information. Morse code became widely adopted in telegraphy and later in radio communications, playing a crucial role in maritime navigation, military operations, and early wireless communication.
that small robot is just out of the world. Morris code is still something I hope becomes a class and it is amazing how he figured out how to make the code by using newspapers. good explanation of the break down the vacuum tube diode. I vote for both too
i vote for Caleb
I vote for David!
I vote David!
I vote for David!
Dr. Joseph explained how scientists discovered a different way to look at a plant breathing.
Have scientists already utilized this new discovery yet?
I vote for both. Thank you
Impeccable science live this week!
I vote both!👍👍👍👍👍👍
science live rocks
Hi from Oregon
I like Caleb. Plus, he likes everything I like.
This Science Live was a great way to start 2026! Thank you for teaching me about the tiny robots, Morse Code, and Vacuum Tube Diodes. My vote goes to David.
How many tornados touched down in the US in 2025?
I vote for both of them because I think they would do good for Acellus.
What a great start to the year! Today’s session was amazing. Anasthesia’s tornado-predicting drone is totally mind-blowing. I also really liked how David and Caleb explained the Edison Effect and vacuum tubes. It made the science really easy to understand. Please bring them back to Science Live again soon!
I like them both, they should team up.
when’s the new conspiracy class coming out? i really want to take it but i don’t have very many courses left.
Good job for Anastasia for getting into her dream major and a great college. I also vote for Caleb. What a good science live like always.
I love the jokes at the beginning of Science Live episodes.
I can not believe the world’s smallest robot is smaller than a grain of salt.
I vote for both! I couldn’t stop laughing when they were explaining about light bulb, very SERIOUS!
They both get my vote
Wow its so cool to see those tiny robots! How do people manufacutre something so small and delicate? And what applications can they have in our life now or in the future?
The Vacuum Tube Diode episode helped me understand how electrons flow from the cathode to the anode and why current only moves in one direction. I also learned how heat causes electron emission and how this technology was important in early electronics. The explanations and diagrams made the concept easier to understand.
I liked learning about the positives and negatives and how the flow of energy works.
I voted for both, I think they both did a great job!
I love Science Live!!!!! I have learned so much!
We vote for BOTH
Hello from Texas, I vote for David!
definitely caleb
I voted calebbb!
I vote for Caleb and David.
I love Science Live
i vote for both!
Loved Dr. Tobias and his talk on the invention of Morse code Samuel Morse. I think that was my favorite part of the video.
I vote for David
I learned that there is a robot that is smaller than a grain of salt! I also learned morse code was made by an artist named Samuel Morse. I finally learned that there are 2 different sound waves one called AC. Which bounces back and fourth and the other one is called DC. which is a straight line.
I cant believe that they can make so small robots, and I vote for David.
I vote for Caleb, and this was another awesome Science Live! Great work!
I learned a new word!! Diode.
I think space is amazing . I would love to go there some day.
Both! Thanks for this video!
I like them both together!
Congratulations Anastasia!
I vote for David!!
I vote for both Caleb and David.
This video was my favorite so far! It was so funny and helped me learn more things. My favorite parts were when it showed the camera gear and I liked the Vacuum Tube Diode too! Also, I vote for David AND Caleb! They both are really smart and funny.
I did not know that robots could be so small, and I did not know the one who invented morse code was a painter, thanks science live also I vote both
I Vote CALEB because we all got big dreams!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
i vote pajet monet
Another vote for David
Hi, I am Bilal from New York. I vote for both!!!!
Another round of peak learning with roger billings
I never knew that robots could be so tiny it literally blew my mind and thank you for again for a great video
i vote for both they are both really smart!!
I vote for David!
Happy New Year!! 🥳🎊
I vote R-51! 😀
Just kidding, I vote Caleb
I love all the facts 💯 ❤️❤️
Great presentations, Caleb and David!
Happy new years, congratulations to Anastasia for getting into college. I vote for David because I feel like he explained more logically but Caleb explained it well too.
Good morning! We are watching as a family.
I love Science Live so much!
This Science Live was fantastic! And I vote David!!
It fascinating that the telegraph & Morse Code was in invented by Mr. Morse die to the death of his wife. Inspiration can come even from tragedy.