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Loose AC connection to electronic piano

I have a cheap synthesizer (Kwai MS710) whose AC connector has come a bit loose. When I jiggle the adapter plug up and down I can often get power to the device (but that's obviously not a long term solution). When I opened up the box I can't see any obvious broken connection under the connector's plastic housing but, again, jiggling it does get results. Any ideas how to go about repairing it? I've never soldered anything before, but I'm certainly game to give it a try.

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  • dbclin Feb 06, 2009

    Thanks for your reply.
    The cable is definitely not the problem as we've tried more than one adapter with the same results.
    Your suggestion about redoing the soldering does make a lot of sense. Where would those soldering points be, though? Should I just solder away blindly under the plastic connector casing? Is it possible to pull the whole casing off of the circuit board?
    I've attached a photo of the device with the AC connector circled.
    I appreciate your help!

  • dbclin Feb 06, 2009

    Aha. That's what I needed to know.
    Thanks a million.


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Your problem is most likely a broken cable in your ac cable. Try to replace the cord first (a place like Radio Shack will have replacements). If it's not the cable, then you might have a broken soldering point inside your keyboard. It might be too small of a crack to see, but redoing the soldering points should work.

Posted on Feb 06, 2009

  • weissmueller Feb 06, 2009

    You have to take the entire circuit board off, the soldering points are underneath. Do not try to pry the connector housing off, it will break. There should be screws holding the board. Be careful to detach all the little wire connectors and re-connect everything properly when you're done. Try not to touch anything on the board and hold it by the edges only.


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