Wonderful project. I learned vacuum and solid-state electronics in parallel so I'm familiar with tube electronics. My fascination with valves go back to my earl

Wonderful project. I learned vacuum and solid-state electronics in parallel so I'm familiar with tube electronics. My fascination with valves go back to my early childhood when I used to move our console-type radio from the wall and touch the grid-1 spigot connection which would make a loud humming sound much to the horror and chagrin of my parents. One of the problems I've witnessed with training in electronics these days is how little time is devoted to vacuum tube electronics. Perhaps that's a necessity given constraints of course time etc. but without an understanding of how vacuum tubes work an important part of one's understanding of the subject is missing. Vacuum tube technology is still a vitally important part of both electronics and of physics experimentation. For instance, magnetrons (microwave ovens, radar, etc.), klystrons, TWTs (travelling wave tubes), high power transmitting tubes (TV, FM) all rely on vacuum tech. So too do PMTs (photomultipliers) and imaging devices such as vidicons and orthicons. In physics, understanding thermionic emission is essential to understanding thermodynamics, so too cold cathode emission and related tech such as vacuum deposition, etc. Even electron microscopes and similar instrumentation relies on vacuum technologies. Unfortunately, now since the widespread adoption of semiconductor electronics much of that vacuum tech tends to be rather specialized so those who've an interest in learning the subject don't get any hands-on experience at an early age. What's great about this project is that it brings vacuum technology to the fore where it can be not only seen but also demonstrated. Learning the transfer characteristics of thermionic diodes and triodes is an excellent way to gain such experience. And to begin one doesn't have to go to such lengths as this amazing project, starting with a single tube superregenerative FM receiver is a good place to start.