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 »
When I first started watching Science Live I didn’t exactly like it but now I love it. 🥹
I vote for Caleb and david
I vote both!
Happy 17th bday me. Thx acellus for giving me amazing opportunities to learn and grow!
I vote for Caleb!! Such a nice Science Live
I vote for DAVID!!!!!
David 100%
I just wanted to say thanks for having this homeschool program I have really enjoyed it and I might go to Pine high school for 7th grade if I go I’ll miss this program.
That’s so interesting that plants breathe in carbon dioxide through tiny hole in their leaves and release oxygen, and humans breathe in oxygen and exhale carbon dioxide!
I vote for Caleb!!!!!!!!!!!
Happy New Year! I vote for both!
Thank you for answering our questions today!
Keep it up guys! This was a good one!
Thank you, Acellus, for your continued support for our students.
I watched with my brother Keaton. I vote for both.
So interesting!! I love watching these videos. I voted David
I VOTE both!
Why does current flow in only one direction in a vacuum tube diode?
I vote for Caleb!!!!
I liked how David and Caleb explain things
The AP literature course sounds so interesting! I love to read and am working on writing a book so this course seems extra awesome to me!
LETS GO CALEB!!!
This video was awesome also I vote for David.
Vote for BOTH
I vote for David. He seems to be a very well rounded young man.
LOVE AREA 51 AND VOTE FOR BOTH
I vote for both!
I really like the new robot and it is very cool how it can swim I also did not now that plants could breath
did we really land on the moon
This was AMAZING 🤩
If we didn’t have plants to expel oxygen, would that be a problem for our planet?
I like how even if your not a scientist you can always invent. also I vote for Caleb.
i vote both
I love science!
I vote for David!
i vote both they are very talented
I believe both would provide a lot to the world but David seems to incorporate science at every point in his life, so if it were science related the vote would go to David.
I vote for BOTH!
But I also am fascinated by the origination of the Morse Code. It really goes to show that when you have an idea to invent/create something that you need to power through “failures” and use them as learning experiences, instead of getting down on yourself that it didn’t turn out how you wanted it to the first time.
caleb is cool
I didn’t know that Samuel Morse was a painter!
caleb and david
I think it was pretty cool Morse Code was used on ships like Titanic
I love r51
My first week here! enjoying the program.
How many tries did it take to make morse code?
This is a fun one! I definitely recommend to all families!
Both get my vote!
This video was fun
I love this Science Live! Both David and Caleb explained the Edison effect, vacuum tube diode, and how to rectify perfectly! i wonder who will have the most votes! I vote for both 😁
Happy New Year from Canyon, Tx! Great job Anastasia! I vote both
This is the first video of the year! YAY!
I vote for David
The AP Literature and Composition course looks fun and interesting! I vote for Caleb!
its cool how the scientist that was going through greif still took his lost to change the world
Acellus is amazing, and the lives always pick the best topics!
I want to vote for Caleb!
I vote both!
Today science live is so good, learning with Drb is so fun!
I vote for David!
I vote for both!
Both get my vote. They are both funny!
I vote for Caleb
I VOTE FOR DAVID! HAPPY 2026!
Never knew plants could breathe!
R51 was very funny, and it’s cool how they suck air from the light bulb and it’s weird that they’re is a stain on only the positive side of the light bulb. Thank you for this week’s science live.
I vote for both!
I vote for Caleb!
I can’t believe they could make a robot so small! That is amazing!
I vote for David!
I vote for both! They are both so awesome!
David for David!
I vote for Caleb
Science live is the best thing I have ever watched!
I vote for both David and Caleb!
I would like to vote both, but if I can’t vote both, then I’d vote Caleb.
I vote for both.
i love how well everything is explained
It was really fun!
I’m voting for both!
thats crazy I never knew plants breathe just like us. Pretty cool to think about
Vote for Both! Caleb and Daviiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiid!!!!!!!!!!!!!!
I vote both!
I vote for caleb
I love this video. I love how both David and Caleb explained. I love how I get to vote and feel part of the family
I vote David I really like the show
It is interesting how an artist could invent such an important thing as Morse code!
I vote both
I vote for Caleb!
Voted for both David and Caleb!
I vote for both
Amazing Science Live!
I vote for both
i like your dad jokes
The connection between the vacuum tube diode and early radios/computers was really interesting. It’s amazing how this basic component laid the foundation for all modern electronics.
I personally vote for both. I think this concept is very innovative and engaging when it comes to engineering.
another for david
I liked how you explained the diode using the heated cathode and anode – the one-way flow of electrons finally clicked for me. Great breakdown of such a simple but powerful invention.
I vote for Caleb too.
I’ll definitely be voting for David!
How many years in total did it take to develop morse code?
I vote for Caleb
both get my vote!!
I vote both!!
I love learning about the new advancments in the world today!
wow!! its amazing how this tiny vacuum tube helped kickstart a lot of what we know about electronics today! 🙂
Caleb has my vote
Love area 51
This is a great way to start the new year.
I love Morse code. I learned about this in my class. It’s cool to have a tiny robot on your finger.
I want to be like David Billings one day!
Learning about the different proteges and how the process of the vacuum tube is very interesting. This is more in depth information on the start of electronics and how this played a big role in what makes the flow of electrons work. Additionally, I vote for both.
Both getting voted for!!!
I vote for Caleb!
these videos always show such cool inventions and it is so awesome to see how they work! i vote both! 😊
I vote both!!
I vote both!!!
I think both are great!
I vote for both because they’re hilarious!
I like how we take inventions from so very long ago and improve them. We need the prior inventors to help us progress in technology today. Breakthroughs are built upon other inventions.
I love science live, also i vote for both.
A robot that tiny is extraordinary! What if they could fly as a coordinated group and transport things like a house robot!
Thank you for offering honors and AP classes!
I vote for both. Learning about the Edison Effect was fun. I never knew that was why a bulb changed color.
I vote bothhhhh!
Loved today’s episode. They have a lotta heart, dunno who to vote for
I vote for Caleb!
I vote David. I love these videos.
i vote for both! cool video!
I thought it was really interesting how Samual Morse who had been a painter before, heard about a new invention where wires wrap around a metal and current is ran through to create an electro magnet. Then it can travel at light speed to connect to a magnet from miles away. After hearing about this he was able to create the telephone, I especially think this is interesting because he didn’t have knowledge in this field before coming up with this idea.
Amazing how many things they can fit onto such a small robot!
I learned so much watching this live today!
I vote for both!
I vote for David!
I vote for Caleb!!!!
I vote for David and Caleb! Great episode. Thanks
I vote David.
I vote for Caleb!! Also congrats to the girl who graduated. What an accomplisment.
I vote both of them. They both did very good.
I vote both. They did a very good job and I love them as a duo!🤩🤩
The Morse code chart was very cool to learn about, seeing it visually helped.
i vote for both!
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I love watching.
I vote for David!
I VOTE BOTH!!!
how did they detect the tornado 🌪️. Also Caleb Caleb Caleb Caleb Caleb Caleb Caleb Caleb Caleb Caleb Caleb Caleb.
I vote for David and thank you for your knowledge I appreciate it.
I Vote Both
I voted for Caleb!!
As always great science live and can’t wait for next weeks!
Both of them did awesome!
I vote for both!!
I vote for Caleb!!!
I vote for both!!
I vote David
I vote for Caleb!
I vote both!
Going with David
One of my favorite episodes to date!
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I vote them both!!
Happy New Year R51!!!
I vote for both!!!
I vote both!!!!
Is ACD2 smarter than the small robot?
i Vote for both
My first science live I enjoyed it
both gets my vote!! awesome!
I vote David!
Wow I don’t know that plants breathe cool science live
I vote for Caleb!!
I vote for both! Great show.
I vote for both David and Caleb.
Thank you DrB!
I vote for both! They are very great!