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Comment by direwolf20

9 hours 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.

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

  • Coincidentally, there were vacuum tubes with dual grids for mixer and AGC applications.

    • And there's someone with a stash of those too. Dual-gate mosfets are one of the ways you know something's been in the back catalog way too long.

  • 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.

    exactly :)

    BF901 FTW.

I use dual gate FETs frequently for all kinds of tricks and they're super useful.

Is that what you had in mind?