Lg 42lc7d uk

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  • jimmler
    New Member
    • Jan 2012
    • 4

    #1

    Lg 42lc7d uk

    Greetings,

    I fiddled with this set earlier in the year and then got sidetracked with some other projects. This is a later revision 42LC7D that does not use the same main board that had the defective coils. It also uses a master/slave set of inverters for the CCFLs.

    The power supply was full of swollen caps and those have all been changed out as well as the 3 electrolytics on each inverter.

    When I apply AC power, the led indicator on the front is red. When I hit the power button, the led turns green, blinks about 3 times, and then I hear an arcing sound near one of the inverters. The sound stops after a couple seconds and that's it. Power light is solid green. I haven't plugged a video source into it yet to check for faint picture or sound. That might make it to today's list.

    I'm thinking maybe one or both bad CCFLs. The first one arcs and shuts down both inverters. I'm not sure how difficult to replace those on this set or even if it's worth the effort. It's a decent set, but nothing outstanding, spec-wise. It's also interesting to note there is only one set of high voltage leads coming out of each inverter. Is there a high voltage distribution board that feeds the rest of the tubes or are there only two CCFLs and they snake around the back of the panel?

    Thanks in advance for any suggestions! It's been enjoyable reading through all the various problems with these sets even if they don't pertain to my model.

    -Jim
  • jimmler
    New Member
    • Jan 2012
    • 4

    #2
    Re: Lg 42lc7d uk

    FYI:

    I decided to disassemble the LCD panel and have a look at the CCFL tubes. It wasn't TOO difficult to get everything apart, but I was being super careful during the whole process. Turns out there are 20 CCFL tubes in this panel and 4 of them were shot. They are tricky to remove as they snap into each side like a miniature glass fuse.

    About the best price I could find on the tubes was $22 each plus shipping. At that point I decided it wasn't worth the additional expense. I'll probably save the boards for future use, tho.

    -Jim

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