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What would your contribution be for a book put together to restart a a civilization? (sopuli.xyz)
submitted 2 years ago* by to c/asklemmy@lemmy.ml
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The title is a bit over dramatic but, per the title, if you could contribute with one piece of knowledge to a book that every single individual should learn from in order to kickstart a civilization, what would be yours?

My personal choice would be the process of soap making, from scratch.

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[โ€“] [S] 4 points 2 years ago (2 children)

Electronic valves are still a thing?

I had relatives that swore on radios based on that technology could endure the detonation of bomb and still work flawlessly.

And I had a colleague in school that saved up to be able to buy a valve based guitar amplifier.

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  • [โ€“] 2 points 2 years ago

    They didn't stop working somehow. The trick is that they need a very high (deadly) bias voltage to work, are mechanically delicate, have to be heated and possibly cleared of gasses leaking in, and from what I can tell have inferior characteristics for a lot of applications.

    On the other hand, your relatives are right about the electrical toughness, and they have no firm upper frequency limit, so they still have industrial niches.

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  • [โ€“] 1 point 2 years ago

    Yeah the guitar amp and vintage HiFi markets keep a few types (mostly power triodes and pentodes but also preamp valves and even a couple of rectifiers) in production, largely in the former Eastern Bloc. There's a few people on YouTube making their own too.

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