1484 Silvertone buzz

Discussion in 'Shock Brother's DIY Amps' started by ArcticWhite, Aug 4, 2021.

  1. ArcticWhite

    ArcticWhite Tele-Afflicted

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    A buddy of mine just bought an unrestored Silvertone 1484 in great condition. I replaced the old electrolytic caps for him.
    Also replaced the cheap original open circuit input jacks with shunted Switchcraft jacks. When I grounded the shunts, the amp buzzes like crazy.
    Is there something about the design of this amp that requires open circuit jacks?


    Screenshot_20210803-222808_Adobe Acrobat.jpg

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  2. Tom Kamphuys

    Tom Kamphuys Tele-Holic

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    Don't know (yet) about the buzz, but I think the input would still be grounded by the unused input with one input used.

    No idea what R5 is doing...
     
  3. Lowerleftcoast

    Lowerleftcoast Friend of Leo's

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    There is a 1M resistor to ground in the original input circuit. If I am following your description of shunting the jack to ground, there would be 68K or 34K to ground in the new circuit. Maybe shunting the jacks is just exposing a current that is flowing in the chassis??? 1M was enough to keep it quiet. 34K maybe not so much.
     
  4. ArcticWhite

    ArcticWhite Tele-Afflicted

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    Dang. Found a cold solder joint on one of my jacks.
    Thanks fellas.
     
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