Troubleshooting Custom Cables. Weird Problem.

Discussion in 'Hardware, Setup & Repair [BG]' started by ridethespiral, Dec 4, 2012.


  1. ridethespiral

    ridethespiral Supporting Member

    Joined:
    Apr 22, 2011
    Messages:
    224
    Location:
    Edmonton, AB, Canada
    I made a bunch of 1ft cables for my pedal board using an old (but decent) cable and Neutrik NP2RX connectors. A few of them work fine and read only <0.1ohm tip to tip & shield to shield. Likewise, they read infinite ohm tip to sleeve.

    The problem cables read 1kohms +-500 tip to sleeve. Not good. :spit: They all look completely fine and just like the cables that work. I know how (love) to solder and I did a pretty good job and took my time using a silver bearing rosin core solder and a 30w soldering pencil.

    The old cable has what I believe to be conductive pvc in it. It goes: inner wire -> conductive pvc? -> insulator -> shield/ground wire -> conductive pvc -> outer insulator.

    EDIT: I believe I have it wrong. It is inner wire -> insulator -> conductive pvc -> shield -> insulator -> conductive pvc. and so having that melted onto the core wire or touching the pin would have effectively shorted the pin to the shield. Would explain everything. Just need to peel that back a bit and resolder.

    Tried searching but I could not find anything exactly like this...

    First image is a good cable, second is one of the culprits. I melted the pvc/insulator a bit when getting the iron in there but I couldn't imagine that would be the problem...All of the connectors basically look exactly like the good one. :confused:
     

    Attached Files:

  2. megafiddle

    megafiddle

    Joined:
    May 25, 2011
    Messages:
    861
    It's either carbonized (burnt) plastic or the conductive layer.

    If you're not burning things, strip back the conductive layer so it cannot contact anything but the shield.
    (actually, you should always do that anyway)

    Some conductive layers are easier to peel back from the center insulator than others. You might be able to
    unwrap it and trim it off. If it does unwrap, you might even be able to remove it after the connections have
    been soldered.
     
  3. ridethespiral

    ridethespiral Supporting Member

    Joined:
    Apr 22, 2011
    Messages:
    224
    Location:
    Edmonton, AB, Canada
    Thanks. It certainly isn't me burning things. Just melted the plastic a bit. When I get the time I will re strip the conductive plastic. It takes a while doing diy cables :/
     
  4. Pilgrim

    Pilgrim Supporting Member

    Joined:
    Jul 8, 2004
    Messages:
    14,143
    Location:
    Fort Collins, Colorado
    I'm wondering what the resistance of the cable is when you don't have ends connected to it.

    If it's the same reading you cite, then the cable isn't a good choice. If not, it's something in the connector installation. Your soldering looks really clean to me.
     
  5. Register to disable this ad

Share This Page