Death Cap...3 Prong? Also, Cap Job but still noisy

Discussion in 'Amp Tech Center' started by GuitarZombie, Mar 13, 2013.

  1. GuitarZombie

    GuitarZombie TDPRI Member

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    Feb 23, 2013
    Location:
    Ohio
    Have an old Univox 1221 that previous owner had partial cap job on. He, or his tech, also installed a 3 prong plug, but it still has it's "Death Cap". Didn't think this was necessary after the mod. ?
    It's a .005 oil filled. I've replaced most every other oil filled cap, as I've read they are horribly leaky. Just the "Death" and 1 in the 2nd channel tone stack and 1 in the reverb circuit as far as those go.
    I completed/corrected the previous cap job, replacing the big boys(main filters and such) as well as the previously mentioned oil filled. Plus most (only 2 or 3 left) of the 'lytics.
    I still have a noisy amp.
    Appears to be in the power section. Still there with volume down on both channels. Didn't seem so in stand-by. One of the 'lytics still to-be-changed is in the bias supply section. Could that be thee bugger? Plan on changing it anyway, just curious.
    Too, the heater wires are not routed the best they could be. How big of a deal could that be?
    One more thought. Tapping on the 6AN8 (phase inverter) next to the power tubes clinks. Microphonic? Switched it with the one in the verb section. Still clinks. Any thoughts there? Possibly that one of the other 'lytics still to change is in the phase inverter section. Haven't traced it out on the board yet but the value on the schematic is the same as 2 of the still-to-be-changed 'lytics.
    Thanks for the help.
     
  2. firemedic

    firemedic Tele-Meister

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    Oct 16, 2011
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    tampa
    Cut out that death cap.
    A cap job means replacing all the electrolytics, including cathode bypass caps, and an old bias cap can definitely create noise.
     
  3. big-daddy-59

    big-daddy-59 Tele-Holic

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    Castlewood,VA
    Yes, lead dress can also have an effect on noise
     
  4. Alamo

    Alamo Doctor of Teleocity

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    Well, with a user name like yours - you need a good death cap :D
     
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