Help to identify jazz electronics and pickups

Discussion in 'Pickups & Electronics [BG]' started by soaf, Dec 6, 2013.

  1. soaf


    Jul 27, 2013
    Hello all... I am hoping to identify these jazz bass electronics. There is at least one EMG sealed pickup. The other pickup has no markings.

    I would like to know...
    1- if everything is complete so I may have a tech install them into a bass
    2- Whether this is all junk and not worth using
    3- what make the electronics are

    The three pots read:
    1) 250K, AUD, 2-35, R820?, 021857
    2) OVL-001-P, ?A, R1378430 (has a "V" sticker for volume)
    3) OVL-001-P, 25K-A, 78430 (has a "T" sticker for tone)

    The question marks represent a digit I cannot make out or hidden behind a solder joint.

    There is a two way toggle with six terminals at the rear.

    There is a square green component mounted to the tone pot that reads 104K100V

    I can provide better pics is necessary. Any info about this setup is appreciated! Thanks for your help.

  2. VVT with 250k and 25k pots and 0.1uF cap. I can't see the switch clearly enough to tell what it does.

    Whoever cut the leads on the EMG pickup basically made it unusable, unless you have plenty of space in the wire channels to fit the solder joints and heat shrink tube that will be required to extend the leads. Don't ever cut the leads on epoxy-potted pickups, because they cannot be replaced.

    Note that you have an active pickup and a passive pickup. You can't use both together, unless you buffer the passive pickup, because the impedance of the active pickup will basically short it out. Note, also, that you have a 250k pot for the passive pickup's volume, and 25k for the others. Pot values that dissimilar are never used together in a passive circuit. When the 250k pot is at "10," its resistance is actually less than 25k, because it is parallel to the 25k pot. This is far too low for the output impedance of the pickup. If another active pickup were used, in place of the passive, then the 250k pot would introduce a very large resistance in series with the pickup, which would basically cause the volume pot to act like an on/off switch.

    To answer your questions:

    1. That is complete, but note the above about mixing active and passive pickups, and using the wrong pot values.

    2. There are salvageable parts, but I personally wouldn't bother with anything there, except the jack, the control plate and the knobs.

    3. Aside from identifying the passive pickup, knowing brands would not be of any value to you. Most of that stuff is mass produced in China and no one really knows who makes it.