Comment by direwolf20 2 days ago
Only because odd components aren't marketable. There used to be 4-terminal MOSFETs, they weren't sold after ICs became normal. Never heard of a multi emitter transistor being sold discretely but it's possible.
Today I learned you can build an entire freaking CPU out of 555s lol
https://hackaday.com/2011/08/05/building-a-computer-out-of-5...
Omg... and thinking that my mother throws a huge stash of components like that. my father was an electrical engineer and ham radio. At least, I managed to save a stash of electronic valves and some analog equipment like an old oscilloscope that could be in a museum (I saw a similar model in a museum).
Dual gate mosfets were a godsend when building RF/IF mixers or preamps. Luckily I have a small stash as they're almost unobtanium and costly these days, but for most uses such as mixers and preamps they can be swapped with a pair or normal jfets in a cascode configuration like this one: https://i.stack.imgur.com/6Nyhg.gif