TurboExpress - looking for schematic to diagnose low power to backlight/lcd

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  • DrunkenMonk
    replied
    Re: TurboExpress - looking for schematic to diagnose low power to backlight/lcd

    Originally posted by stj
    post lots of pictures, i have an idea.
    Took two high-ish res photos, there's a couple of scratches into the solder mask on either side where the glue was removed, but upon checking they seem to be just the mask and I've got epoxy to tidy that up after I get the backlight working as intended.





    And here's the backlight when it's turned on at full or low power

    Last edited by DrunkenMonk; 01-30-2021, 01:06 PM.

      Leave a comment:

    • stj
      replied
      Re: TurboExpress - looking for schematic to diagnose low power to backlight/lcd

      post lots of pictures, i have an idea.

        Leave a comment:

      • DrunkenMonk
        started a topic TurboExpress - looking for schematic to diagnose low power to backlight/lcd

        TurboExpress - looking for schematic to diagnose low power to backlight/lcd

        So as per the title, I've got a turboexpress here that was recapped with nichicon caps, the fuse and one of the coils was replaced (possibly popped due to an over-voltage or negative voltage?) and the audio is now great but the backlight doesn't show a bright vibrant white like it should, and doesn't look like it adjusts at all using the wheel, but after checking the wheel it looks like it's reading fine, so I can only assume I'm not getting the correct voltage somewhere... FUN

        So I'm not sure if it's part of the coil circuit or one of the regulators since I don't know what they should be outputting or where the backlight circuit is in it's entirety.

        If anybody has some schematics, ideas or even just some chickenscratch notes I'd be very appreciative
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