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miswiring = dead battery?

Discussion in 'Pickups & Electronics [BG]' started by jondog, Jun 12, 2005.


  1. jondog

    jondog

    Mar 14, 2002
    NYC metro area
    I installed a Jackson preamp in my SX and it sounded great, but when I came back to it in a week or 2 the battery was dead. I didn't leave it plugged in, so I'm assuming I miswired the circuit so that the battery stayed on. What should l look for when I open her back up?
     
  2. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    double check where you put the battery ground wire. If that's always going to ground, the circuit is complete and your battery wiil drain
     
  3. Make sure the input jack has 3 leads, not just 2. 1=signal hot (tip of plug), the 2nd=ground connection (shaft of plug), the third = - lead of battery. When the cord is plugged in, the 2nd and 3rd lead are connected, powering the internal preamp.

    Verify when the cord is unplugged, the power is disconnected, check for voltage at the circuit board.

    My guess is you hooked the - of the battery to the ground connection (ring, shaft of plug), so its on all the time, and the signal ground is what's getting switched on when you plug in the bass instead of the - of the batttery.

    |
    1 signal hot ------v | plug
    | <====
    3 batt - -----------------v---^ |
    2 circuit ground --------------------------------|

    When bass unplugged, there's space between 2 and 3, they're not connected. No power goes to preamp circuit. When plugged in, tip of connector touches 1, shaft of connector touches 3, and moves it over to contact 2, which completes the power connection. Or the shaft of the plug makes the connection, instead of bending 3 into 2. I've seen both. But if you hook battery - to terminal 2, its always connected to preamp circuit.

    Randy

    Ok, drawing looks like crap when posted..... I'll try it horizontal...

    Plug:
    II
    II
    V

    _____________ <=2 circuit ground (ring of jack, signal gnd)
    |
    |
    | >
    | |
    | <
    | |
    | |
    | |
    | |
    | |
    | | >
    | | |
    | | | <= 1 tip of plug
    | | |
    | | |
    | |
    | |<-- 3 (-) of battery
    |
    | <= 2, signal ground (ring of jack)
     
  4. jondog

    jondog

    Mar 14, 2002
    NYC metro area
    Thanks guys. I think I got confused w/ grounds and wired way too many things to lug #2 on the jack. Can you tell me which ones to disconnect and what to do w/ them? It has

    - Black from pup
    - White from bridge
    - Black from 9v
    - System Ground from preamp board

    right now, and that should be why my battery died.
     
  5. I think just the black from - of battery. Everything else can be grounded full time.

    Randy
     
  6. jondog

    jondog

    Mar 14, 2002
    NYC metro area
    ok how do I full time ground the other 3?
     
  7. jondog

    jondog

    Mar 14, 2002
    NYC metro area
    I tried soldering the other 3 wires to a pot casing and replaced the dead battery. Now I get no sound at all :(
     
  8. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
  9. jondog

    jondog

    Mar 14, 2002
    NYC metro area
    Thanks! It's going now, I'll let you know if the battery still works in couple weeks :D