Home › Forums › Help/Technical Questions › Vintage EHX Clone Theory Chor/Vib knob does not do anything

Viewing 9 posts - 1 through 9 (of 9 total)
  • Author
    Posts
  • January 15, 2021 at 4:21 pm #86550
    Sanshiro
    Member

    Hi, I recently purchased a vintage Clone Theory, the model with the flange switch. The Chorus/Vibrato knob does not appear to do anything when turned, and it seems to be stuck somewhere towards the vibrato setting. I figured the pot might have been bad so I replaced it with a 10k linear as the schematics suggest, and yet there’s no change, same issue. Any ideas as to what my issue might be? Both the Rate and Depth pots appear to work fine.

    January 15, 2021 at 4:30 pm #126734
    The EH Man
    Moderator

    I would suspect a broken trace going to the pads the pot is soldered to. Barring that, there may be an issue with the flange switch.

    January 15, 2021 at 4:33 pm #126735
    Sanshiro
    Member
    Quote:
    I would suspect a broken trace going to the pads the pot is soldered to. Barring that, there may be an issue with the flange switch.

    I was going to try and reflow the solder joints in a bit here, I was thinking there might be a cold joint somewhere as well, but I will check for trace continuity as well. When I switch between flange and chorus mode, there is a pop, is that normal behavior?

    January 15, 2021 at 4:34 pm #126736
    The EH Man
    Moderator

    Yeah, I wouldn’t worry too much about that.

    January 15, 2021 at 4:36 pm #126737
    Sanshiro
    Member
    Quote:
    Yeah, I wouldn’t worry too much about that.

    Alright thanks. I will check for continuity and touch up the solder joints. Is there a possibility of the MN3007 being bad, or do you think it’s more likely to be a physical issue somewhere?

    January 15, 2021 at 4:40 pm #126738
    The EH Man
    Moderator

    If you’re getting some modulation I’d say the MN3007 is OK.

    January 15, 2021 at 4:43 pm #126739
    Sanshiro
    Member
    Quote:
    If you’re getting some modulation I’d say the MN3007 is OK.

    In Chorus mode it’s definitely getting modulation. When in flange mode though it doesn’t really seem to have anything, just depth and rate settings affecting the sound.

    January 15, 2021 at 5:29 pm #126740
    Sanshiro
    Member
    Quote:
    I would suspect a broken trace going to the pads the pot is soldered to. Barring that, there may be an issue with the flange switch.

    Doesn’t appear to be any bad traces, all get continuity, there are some scratches here and there over the trace coating all over the board but none that affect the signal. Really odd.

    Edit: though when I do turn it on after having been unplugged, I have to switch back and forth once or twice between flange and chorus for the modulation to work in chorus mode. After that it’s fine, is that normal too?

    January 17, 2021 at 8:12 pm #126749
    Sanshiro
    Member

    Okay, I think it may have been something to do with the flange switch. I took it apart, (then all the contact pieces on the actual switch piece came flying off, should have seen that coming), cleaned it up a bit, and now the pot seems to function as it should. However it’s still intermittent, sometimes the pedal has no modulation and the switch needs to be flipped a few times back and forth for it to kick in, but the chorus/vibe knob seems to work fine now.

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