I love vacuum tubes

Discussion in 'Off-Topic' started by KL7AJ, Feb 11, 2016.

  1. KL7AJ

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    Interesting history:
     
  2. profbuxton

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    I would too, if there was any thing in it!
     
  3. KL7AJ

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    0 is a number, too!
     
  4. Lestraveled

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    The sound of Rock n Roll is based on the vacuum tube. With all of the engineering poured into it over the years, nothing replaces it.
     
  5. nsaspook

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    Most of my early shipboard technician life was spent working on vacuum tube technology equipment. I didn't love tubes then and I don't love them now. Try maintaining a room filled with 390 receivers, a tasks group src20 set or a spa-8 in the tropics with minimal or no AC in the room. Love is not the word I would use for that experience.
     
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  6. Glenn Holland

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    It's a lot like the old fashioned elevators with mechanical selectors, relay logic and AC/DC motor generator sets.

    They're fun to watch and listen to, but a pain in butt to whoever maintains and repairs them.
     
  7. Hypatia's Protege

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    So do I!:D:D:D

    For the record --- Only at such time as EUV through 'hard' X-Rays (to at least 100 MeV) may be produced via semiconductor devices (composed of stable nuclides/isotopes) might one argue that electron tubes are wholly obsolete -- Then too, such indispensable (and ubiquitous) instruments as EMs, MSs and, indeed, all manner of particle accelerators, are, in essence, 're-entrant' electron tubes...

    But here's a thought -- The Crookes tube (which being an experimental/demonstration CRT and X-Ray tube) is often cited as the earliest electron tube -- The irony (such that it is) being, inasmuch as a 'semiconductor realization' of the latter function is unlikely, that one is put in mind of the Bard's immortal line: "She, she at least, shall stand to the last even as she was first..." (Possible [proximate] paraphrase)...:cool:

    Best regards
    HP:)
     
    Last edited: Feb 12, 2016
  8. ISB123

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    I hate Vacuum tubes but I love Nixie tubes:oops:.
     
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  9. nsaspook

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    Tube are not obsolete but are (thank goodness) no longer general purpose devices for electronics.

    I'm still the 'tube' guy.:p
    http://forum.allaboutcircuits.com/threads/tube-creep.113198/#post-880679
     
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  10. #12

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    Quote from some old guy disparaging transistors: "There is nothing a tube can do that 5 or 6 transistors can't do.":cool:
    I assume he was thinking about a pentagrid converter.
    I also assume he was wrong about high energy circuits. There is definitely a limit to how much voltage you can connect to the pins of a TO-220 package.:D

    In reality, 5 or 6 transistors still require less power than a pentagrid converter.
    And while I'm here, I would like to discourage people who say transistors don't wear out. They don't get low emission from their cathodes, but ECG and I made a living replacing transistors that failed.;)
     
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  11. nsaspook

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  12. KL7AJ

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    I bench pressed a LOT of R-390s into racks....singlehandedly. And I STILL love them!
     
  13. KL7AJ

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  14. JoeJester

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    Hey, they even made a phantastron oscillator using transistors. Of course the vacuum tube model was a pentode.

    I remember lugging around those old Tektronix scopes.

    [​IMG]
     
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  15. Hypatia's Protege

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    My principal 'gripe' with 6BK4s (and their ilk) was the @#$% 'integral shielding':mad: --- That said, 80keV shines on through quite nicely!:D:D:D -- No kidding! 6BK4s and 6EN4s will 'take' upwards of 100kV (cold 'cathode' inverse polarity) sans internal flash-over (following Ca. 1 hour 'pre-seasoning' in normal, forward operation [i.e. ≈ 20kV @ 5mA]) --- Needless to say, said off-label operation requires immersion in dielectric oil -- To my erstwhile youthful perspective, the apalling focal geometry was adequately compensated by economy:cool::cool::cool:

    Nostalgically
    HP:)
     
  16. Hypatia's Protege

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    Hey!:D --- I've yet an entire complement of 1Lxx series SA plugin units -- and, I daresay, a few 525 'mainframes' somewhere...
    They may have been 'boat anchors' but giving them their due -- they were designed/constructed to higher quality standards than most equipment (in the $75K- $200K range) available today (if MTBF is any indication:mad:):):):)

    Best regards
    HP:)
     
  17. nsaspook

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    I remember the (happy) day we junked all but a few of the R-390s and replaced them with the R-1051. (that still had two tubes LOL)

    Maybe I worked too long in the Donut shop.
     
  18. nsaspook

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    That scope cart was build like a tank. I still have a few at work converted to custom mobile test racks.
     
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  19. KL7AJ

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    I've installed those too! FINE FINE radio...the synthesizer rocked.
     
  20. KL7AJ

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    I have TWO 545s with EVERY plug-in Tek made for them. :)
     
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