Yellow Jacket Problem (74 Twin Reverb)

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by mcflymcflymcfly, Sep 26, 2006.

  1. mcflymcflymcfly

    mcflymcflymcfly Member

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    So earlier tonight, i pulled my four 6l6's out of my 74 twin reverb, i then put in two yellow jackets in with el84's i believe.. but, i failed to notice that the plastic piece in the middle of all the "prongs" on the yellow jacket had been broken off. i then turned my amp on standby and noticed that only one of the tubes was powering on. Next i decided to do something very stupid and i turned the amp to full ON. The noise and the "small explosion" if you will, was not good, i then pulled the yellow jackets and put all 4 6l6 tubes back in. i powered the amp on, and i am getting a VERY LOUD buzz, the amp still works and i can play a guitar through it, but the buzz is unbearable. My knowledge is VERY limited with this amp, and any help would be much appreciated. Thanks!
     
  2. brad347

    brad347 Member

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    You might've melted a screen resistor
     
  3. mcflymcflymcfly

    mcflymcflymcfly Member

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    how easy/pricey of a fix are we talkin?
     
  4. brad347

    brad347 Member

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    very easy, very cheap if you DIY it. If that is in fact what it is.

    I say open it up, slide the chassis out a few inches and look at the power tube sockets (don't touch unless you know what you're doing).

    See anything that looks burnt? Play a game of "one of these things is not like the others" to see if anything is suspect.

    I recommend replacing any resistor mounted on the power tube sockets with a higher rated metal-oxide or wirewound flameproof resistor. They originally used carbon comps and they do not hold up to the heat well.

    If you have a soldering iron, you can do it yourself fairly easily, and the cost of parts numbers in the cents, not dollars. This is assuming, of course, my wild guess is right.
     
  5. mcflymcflymcfly

    mcflymcflymcfly Member

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    looks like i completely burnt one of the "caps..." that is directly overtop of the tube socket.
     
  6. brad347

    brad347 Member

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    just as i suspected. Replace all four of them with heavier duty replacements. I recommend 5-watters. Keep the ohm value stock and there will be no change in tone.
     
  7. mcflymcflymcfly

    mcflymcflymcfly Member

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    i actually took it to a friend of mine, i fried a resistor cap(470 ohms), so i just gotta get a new one of those, basically 80cents cdn, plus a gift certificate for swiss chalet for my friend hehe :) so pretty cheap fix..
    thanks very much for the help :)
     
  8. brad347

    brad347 Member

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