Comment on We used to have TV repairmen who would come if dad couldn't fix it with the tube from the grocery store kiosk. Weird.

JohnnyEnzyme@piefed.social ⁨4⁩ ⁨days⁩ ago

• BradleyUffner@lemmy.world ⁨4⁩ ⁨days⁩ ago

  My best guess is that they are probably referring to a degaussing hoop. You used to be able to rent / borrow those to try to fix your TV if you kid played with magnets near it. If never describe it as a tube though.

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  • JohnnyEnzyme@piefed.social ⁨4⁩ ⁨days⁩ ago

    I remember those, but for tape deck heads, not TV’s.

    Anyway, Scirocco came with the very likely correct analysis, if you can see the other comments in this chain.

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• Hupf@feddit.org ⁨4⁩ ⁨days⁩ ago

  It means the shower might have been too hot?

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  • JohnnyEnzyme@piefed.social ⁨4⁩ ⁨days⁩ ago

    I’m afraid I’m more lost than ever.

    This is about TV repair, right?

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    • Scirocco@lemmy.world ⁨4⁩ ⁨days⁩ ago

      Old televisions used vacuum tubes in their circuitry in a similar role to transistors in (more) modern electronics.

      These were literally little glass bulbs with bits inside that heated up, glowed and did magical things with electrons. They had some number of pins on the bottom and plugged into the television board similar to CPU sockets (but with only 5ish pins in a circle)

      These tubes were not particularly long-lived and were fragile physical devices. When they were “on the fritz” it was literally often possible to smack them back into place/alignment/operation. Hence the trope of a TV with a bad picture, slapping it around and voila it works again. This was a literal thing that really happened and works, at least until the internals of whatever tube were too far out of alignment.

      At this point, rather than call an expensive repairman (always a man in those days), you could take your suspected bad tube to the grocery store, where there might be a machine that resembles a 1980s arcade cabinet, which has a bunch of various common vacuum-tube sockets on it. Dad will plug the ‘bad’ tube into the (in)correct socket and the machine will pronounce that tube to be GOOD or BAD with some version of accuracy.

      With that information, dad can select a new identical or similar tube from the rack that’s under the testing board, inside the cabinet.

      Maybe it will work, maybe not.

      Lots of specific tubes were replaceable with more generic versions that “will work” and there was a lot of effort to consolidate the vast number of tube variants, so another important tool was the equivalency chart-- look up your old tube in a book of tiny print/tables and see what generic part number might work to ‘fix’ the TV

      Without having to call the repairman to your house, which was also very much a real thing.

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      • JohnnyEnzyme@piefed.social ⁨4⁩ ⁨days⁩ ago

        Ah shoot, I’d completely forgotten about vacuum tubes. Everything fell in to place with that reminder, but it was fun reading what you had to say about these things. Thanks for that nice writeup!

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