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Best way to fix a clip?

Discussion in 'Amps and Cabs [BG]' started by BullheadBoris, Nov 30, 2016.


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  1. BullheadBoris

    BullheadBoris

    Nov 30, 2016
    the white rectangular clip in front of the first black cylinder - the sound cuts in and out, and when I tap on that, it seems to be what's causing it to happen. Does anyone know how to fix one of those clips? I'm wondering if one of the four wires going into it just isn't in far enough or what, but I was under the impression that it had just been replaced, attempting to fix the problem, but still, it persists!
     

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  2. EarnestTBass

    EarnestTBass

    Feb 3, 2015
    I am not a technician, but I believe that what you are calling "the first black cylinder" is a capacitor. Capacitors are capable of storing lethal electrical charges. I would refer to the "white rectangular clip" as a wiring harness connector.

    Again, I am not a technician. However, I can state that you might be messing with something that you don't understand and you might get hurt- or worse. Beyond this I can offer no advice.

    I apologize if I have insulted you. If I have prevented you or some one from causing injury, then "you're welcome"
     
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  3. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada
    At your present state of technical knowledge may I humbly suggest taking the amp to a proper Tech. The damage your inexperienced hands can do, it is the best and the cheapest, in the long run, option.
     
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  4. Those plugs usually have a little metal thing on crimped on the end of the wire and then they "click" in to the white connector proper. I would pull the intermittent plug and take a look at the metal connectors. It's possible that one of them isn't "clicked" all the way in OR that the opening in the end of the connector is enlarged. Likely. The best way to fix this is to figure out how to pull the wires-one at a time- from the white connector and "squeeze" the opening a bit and check that the crimp is tight on the wire. Your connector is probably like the batch on the right side of this photo. HOWEVER. If one of these wires is connected to a capacitor, like the black cylinder you refer to, you might have a huge -shocking- problem on your hands. Time for a trip to the amp doctor....really.
    -1.
     
    Last edited: Dec 1, 2016
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  5. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Like Paul said, you are probably better off having it properly diagnosed before assuming (likely incorrectly) that the problem is the connector. Nothing worse than making the problem worse and more expensive than it is now.

    A real, qualified service tech should be able to take smcare of this and warranty the repair.

    A little more on the warranty aspect, all repair work should include a warranty that backs up the promise of proper repair by putting their money where their mouth is.
     
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  6. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada
    YEAH!! What ^ he said! :D
     
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  7. BullheadBoris

    BullheadBoris

    Nov 30, 2016
    Hi, im sorry. Yes, I just got it back from someone that replaced that very connector. I apologize, I didn't give any extra info. I'm used to working with this kind of stuff (not in amps) I just don't know the proper buzzwords for them. These clips are slightly different than the ones I've used before, (where the area to depress them was easier to push in order to extend or retract the exposed wires inside.) I just don't have anything thin enough to depress the thing that clamps the exposed wires, themselves, inside that harness.

    I initially found the harness halfway detached from the four metal prongs that go up into it. I snapped it back into place and that seemed to fix the problem. Or so I thought until I was at the show i was playing, set up, and about to begin.... really annoying. A friend (who owns and operates an amp company) said he replaced the harness. It seemed to work again, but then showed the same signs as before. Everything looks tight and connected but just barely touching the wires that go into the harness seems to cut the sound on and off completely. (I play sludgy stuff, so this thing vibrates a lot!)

    Does anyone know what to use to or how those wires are held into place inside the harness? Or if there needs to be a crimping tool or something to get those wires in there?
     
  8. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Have you considered that the connector may NOT be the problem? How do you KNOW that it is?
     
  9. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada
    BTW Boris - a very warm welcome to TalkBass!

    To answer your last question many of us do know but to give you that information would do you an injustice. If you cannot identify the parts that you are looking at you should not be inside an amplifier. Please read post #3 again.
     
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  10. BullheadBoris

    BullheadBoris

    Nov 30, 2016
    I understand, and thank you. Honestly, it's the terminology I dont know. I've built a computer in its entirety, I know that has nothing to do with an amp, but it speaks to the flavor of ineptitude that I have. That is to say, I don't know basic details, but I'm not stupid in a way that someone would think it's okay to lick a connector and get themselves killed!

    Honestly, I'm going to try to fix it myself anyway. I don't have the money to take it somewhere and my friend replaced the connector for free. So I have zero other options regardless of warnings. I do appreciate it, though! But yeah. I owe more money than I'm bringing in... I'm not in the amp-fixing bracket right now, but giving up the only thing that I enjoy doing isn't an option either!


    To answer Agedhorse's question, I believe it's the connector because it's the only thing in the entire area that reproduces the problem, and i mean, within a millimeter in any direction from it. I can move everything else violently and have no loss of connection, but gently blowing on that specific area will reproduce the loss.

    I genuinely appreciate the concern for safety. Thank you
     
    Last edited: Nov 30, 2016
  11. Pretty good explanation for "not a technician."
    I AM a technician an concur with everything you said with one small exception.
    In this amp, I would not categorize the capacitor voltages as being lethal, rather I would say dangerous.
    You get even a little tingle of a shock and the normal reaction is to jerk your hand away.
    In the process, you scrape your wrist over some sharp edge in the chassis, severing an artery, then you bleed out and die. So well, you were correct after all, it could be lethal.

    OP... discharge the caps before digging around the innards of an amp.
     
  12. BullheadBoris

    BullheadBoris

    Nov 30, 2016
    Discharged! thank you!
     
  13. Jeff Scott

    Jeff Scott Rickenbacker guru.......... Supporting Member

    The first thing that came to mind was Darwin........................
     
  14. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada

    You do not short a capacitor to drain it so please don’t do this that way. Generally a SS amp will have discharged it supply caps as the power fades. Not saying you said that OGB but some do think this is the correct method.
     
  15. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada
    Boris, if you’ve built a Windows machine that really doesn’t count! :D LOL
     
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  16. Good point.

    You can also discharge through a resistor to drain the energy off more slowly.
     
  17. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    But note that with large value capacitors there is enough energy stored to make a smaller (say 5 watt) resistor finger melting hot.
     
  18. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Then you need to look carefully and see if you can identify the source of the intermittent, much more likely that it's the make side of the connector soldered to a single sided PCB.

    It's also possible that it's something else on the board, it's amazing how difficult an intermittent can be to find... even one that pretends to be very simple. It can also be a crack or fracture between a pad and trace, or even the trace itself. All of these can have identical symptoms.
     
  19. EarnestTBass

    EarnestTBass

    Feb 3, 2015
    I built a few Heath kits back in the day. And I lick 9 volt batteries to check the charge. That's the extent of my qualifications as an electrician. I also heard a story of a man who died when he attempted DIY repairs on his old TV....

    I knew that if I was the first to post a response, someone who actually knew what he talking about would soon follow and expose me for the fraud I am. I erred on the side of safety until Boris could get real advice.
     
    Jason Hollar likes this.
  20. In my experience (lots of very old electronic gear) - the two most common failures are dirty connectors (oxidation) and bad solder joints. I'll agree with everyone urging caution and to take it to a pro ---- but with that said ....

    Usually if it's the connector being dirty and oxidized, just plugging/unplugging it a few times burnishes the contacts and solves the problem. But if it continues to be intermittent after that (or if it gets worse after that), it "probably" is a cold solder joint maybe where the pins for the connector are joined to the circuit board (or the trace that they solder to has cracked/broken/lifted off the board). Of course it could be a million other things --- but those two would be the first place I'd look.
     
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