This is a beautiful video. I have a general concept of what's going on - maybe someone with more knowledge can correct me: the video shows the guy building a te

This is a beautiful video. I have a general concept of what's going on - maybe someone with more knowledge can correct me: the video shows the guy building a tetrode, which is a way to either control voltage or current depending on how its used. In the testing portion of the video he shows the current response as he varies the voltage through the tube... (?)