Do all tubes have secret codes?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by mbratch, May 28, 2008.

  1. mbratch

    mbratch Member

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    I know I've seen the etched code on some tubes to ID them, but I have a 5U4 that I can't find an etched code on.
     
  2. Blue Strat

    Blue Strat Member

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    No. You have to know what to look at INSIDE the glass. Often, the typeface used for the tube number is a tipoff as well.

    Got a photo?
     
  3. mbratch

    mbratch Member

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    At long last...

    [​IMG]
     
  4. UR12

    UR12 Member

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    based on the octagon around the 5U4 it's an RCA that was made in the USA
     
  5. daddyo

    daddyo Guest

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  6. mbratch

    mbratch Member

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    Thanks UR12.

    Cool pic, daddyo. ;)
     
  7. rockon1

    rockon1 Member

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    Wrong code! lol!
     

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