Old solid state record player

Discussion in 'General Electronics Chat' started by danray35e, Jun 14, 2005.

  1. danray35e

    Thread Starter New Member

    Jun 14, 2005
    [attachmentid=720]I am working on this old record player. Everything on it works but the sound.
    I have checked all the wires from the speaker and the needle and the wires are good. I am an electrician by trade, but my knowledge on electronics is limited. I am not sure what to check first and not entirely sure how to check it.
    Any ideas as to what I should check would be appreciated. I have attached a picture of the circuit board.undefined
  2. beenthere

    Retired Moderator

    Apr 20, 2004

    Some guesswork here. The terrminals on the left pot should be for a switch. If it opens and closes with the control shaft, then the right capacitor should have a DC voltage across it when everything is hooked up. The diode next to it looks like the rectifier. Check the pots, too. A meter should show resistance across the outer legs of each pot, and the center one should read to both outer legs.

    If you have power, then all else depends on the PA234 ic. With everything connected and powered up, touch each of the ic's legs, one at a time, with a small screwdriver. Touching one should produce a loud buzz in the speaker. If not, you may be out of luck. The PA234 is made of unobtainium, and probably can't be replaced (it probably went out of production some years ago).