Viewing 9 posts - 1 through 9 (of 9 total)
  • Author
    Posts
  • #21293
    Anonymous
    Inactive

    i have build black dog kit  and i don’t understand why i have just a little sound,  all controls seems working but i hear just a little sound and big breath when all pots are pushed to the max…….with little sound……sorry for my bad english,  i hope you understand.

    what do you mind about this ?

    #21295
    Barry
    Keymaster

    Pictures.

    #21301
    Anonymous
    Inactive

    hi barry, nice to meet you !

    #21303
    Barry
    Keymaster

    Before I begin looking this over in detail what do you have protecting the bare back of the metal Potentiometers from contacting the solder side of the board?

    #21304
    Anonymous
    Inactive

    yes i have “bumpers”  on the back of pots…….

    #21319
    Barry
    Keymaster

    First I would make sure the transistors are seated good. Bend them a bit if you need. Make sure they are sitting tight in the sockets.

    I know it might be hard to re-flow but try and reach as many solder joints as you can and re-heat them to make the solder flow again. You want to have some extra solder handy if you need to ad a bit more.

    You can bend the pots up so you can reach more solder joints but be careful.

     

    If none of that helps take some voltage readings of the transistors and report them here.

    Example:

    Q1

    D = _.__

    G = _.__

    S = _.__

    Q2

    D = _.__

    G = _.__

    S = _.__

    Q3

    D = _.__

    G = _.__

    S = _.__

    #21325
    Anonymous
    Inactive

    hi barry
    i’m a king of soldering irons, i make perfect welding 🙂
    but!!!!!
    i have 2n5088 transistor !
    and when i put this one instead one of the bs 170…… i have sound……just with light gain but strong, maybe the 2n5088 make less gain than a bs170 ?
    seems this one of the bs 170 not works !
    possible ?

    #21329
    Anonymous
    Guest

    The 2N5088 is a NPN transistor.  This circuit uses MOSFETs.  The 5088 will not bias properly in this circuit.  Besides, the special tone of this circuit comes from the BS170!

    Install BS170 and troubleshoot from there.

    #21332
    Anonymous
    Inactive

    ok,I’m gonna buy a bs 170 a musikding at my next order, I think the problem is this defective bs 170…..thanks for your support…..
    thanks very much !

Viewing 9 posts - 1 through 9 (of 9 total)
  • You must be logged in to reply to this topic.