Does this wiring diagram make sense?

Discussion in 'Luthier's Guitar & Bass Technical Discussion' started by xilef_regnu, May 1, 2008.

  1. xilef_regnu

    xilef_regnu Member

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    I downloaded this Guild solidbody guitar schematic and am puzzled by the indication of 3 separate grounds, is that really indicated?

    Also, what do you think the sliding switch is really doing in this scheme?

    (I admit to being a novice at this stuff.)

    [​IMG]

    Thanks in advance!
     
  2. RvChevron

    RvChevron Member

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    The grounds are all soldered to either the back of the pot or any shielding piece. They are/should all be connected together at the end.

    The switch changees the phase , in accordance to the other pickup, by reversing the hot and ground wires. Therefore, when both pickups are used together, instead of having that twangy mid position sound, you get a peter greenish out of phase, nasally sound.
     
  3. xilef_regnu

    xilef_regnu Member

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    Thanks for your observations.

    This guitar definitely has some grounding issues. The bridge pickup is extremely noisy. I was surprised, when I took a look, to see that the output jack is not grounded to the bridge. Instead a tone pot is. Any thoughts?
    [​IMG]

    [​IMG]
     
  4. RvChevron

    RvChevron Member

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    Can you take a pic without flash? The bright glare makes it hard to see.

    The back of the pots, bridge, output jack ground and pickups ground should all be connected to each other and have full continous conductivity to each other.
     
  5. xilef_regnu

    xilef_regnu Member

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    Here's some shots without flash. Detail seems to be about as good as my camera will do.

    [​IMG]

    [​IMG]

    [​IMG]
     
  6. RvChevron

    RvChevron Member

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    OK, for one, the outside tabs/lugs of the two volume pots that are connected to the output ground, should also be connected to the back/casing of the pots.
     
  7. SatelliteAmps

    SatelliteAmps Member

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    And the wire off the back of the tone pot going under the pickguard should be going to the bridge as a ground wire. So if all the grounds were together, then the output would be grounded to the bridge, so to speak.
     
  8. AndrewSimon

    AndrewSimon Member

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    Everything looks fine to me.
    Take an ohm meter and make sure all the grounds are connected.

    As for the noise, the only thing you can try is shielding and while you're at it do a star ground wiring.
    (all grounds run to one point and no ground loops)

    :rolleyes:
     
  9. Tone_Terrific

    Tone_Terrific Member

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    A phase reversal switch on a 2 conductor pup is a recipe for noise as the shield/unshielded conductors are reversed by the switch...unless I am seeing this wrong. I looks like it noise should lessen in the non-reverse position.
     
  10. xilef_regnu

    xilef_regnu Member

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    If you could point me to a description of how to do these, I would appreciate it!
     
  11. xilef_regnu

    xilef_regnu Member

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    Yes, one position is considerably less noisy than the other...
     
  12. AndrewSimon

    AndrewSimon Member

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