Some recent threads reminded me of how much I liked glass diodes when I was a kid. They seemed so cool. Pretty, and finely made. They seemed marvelous, and how you could manufacture them, so tiny and perfect, provoked a lot of thought.

I also really liked vacuum tubes because you could see the parts in there, and picture how they worked.

 

I also really liked vacuum tubes because you could see the parts in there, and picture how they worked.

And see red hot anode or screen grid and see arcing inside!
BTW it still worked after these events.

 

My ultimate electronic memory is from the fifties; a large three phase mercury vapor rectifier, flickering and glowing - like a sci-fi Martian in a bottle!

 

My ultimate electronic memory is from the fifties; a large three phase mercury vapor rectifier, flickering and glowing - like a sci-fi Martian in a bottle!

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Yes. Those Gas Filled Thyratrons.