Pyramid 7" LCD - No stable picture

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  • pentium
    Badcaps Legend
    • Mar 2006
    • 2778
    • Canada

    #1

    Pyramid 7" LCD - No stable picture

    I picked up this dinky 12V LCD panel at a flea market and it has at the least a composite video input however when I power it (from a bench PSU), all I see is a white screen with a horizontally unstable picture.



    That should be the "PYRAMID" logo (sometimes it's a bit cleaner but it's always looking like that) but as you can see, it's pretty hard to make out.

    Inside the unit:



    It has a really nice CASIO LCD controller and subsystem but the video input controller and overlay board is garbage. Poorly soldered joints and it just looks like something you would get in a kit. Reflowing yielded nothing but I'm eyeing these caps.


    Could these be the source of my problem?
    Also, I didn't get to see what the panel was like if I fed it a video signal.
    Find Nedry!


    Check the Vending machines!!

    <----Computer says I need more beer.
  • tmwalsh
    Senior Member
    • Jan 2009
    • 119

    #2
    Re: Pyramid 7" LCD - No stable picture

    Is the last image a picture of the board at the bottom of the 1st picture flipped over and end-for-end? Doesn't really matter, but replacing the caps on that board would be a low cost experiment. The farthest to the left looks dodgy to me, with apparent 'white stuff' leaking out the bottom.
    As they say "It couldn't hoit..."
    tom

    Comment

    • Wizard
      Badcaps Legend
      • Mar 2008
      • 2296

      #3
      Re: Pyramid 7" LCD - No stable picture

      The LCD itself is a composite, focus your capacitors check on that. The purple cap is polymer.

      Cheers, Wizard

      Comment

      • mbates14
        Senior Member
        • May 2005
        • 169

        #4
        Re: Pyramid 7" LCD - No stable picture

        i had a couple of LCD displays that were a different brand, but exact setup as yours, with the exact problem. turned out to be an issue with the panel itself and i never did fix it. so if you figure it out, give me a heads up.

        Also, that panel setup isnt even an active matrix TFT, its a piss-poor low contrast passive PSTN display. and once working, the picture will look awful.

        Comment

        • pentium
          Badcaps Legend
          • Mar 2006
          • 2778
          • Canada

          #5
          Re: Pyramid 7" LCD - No stable picture

          So you say it's the LCD panel itself that is probably the problem and not the other components like the controller or overlay boards? Damn.

          I don't need a super high resolution. I was going to mount it on my CCD-V5000 camera and use it as a monitor and substitute for the b/w viewfinder.
          Find Nedry!


          Check the Vending machines!!

          <----Computer says I need more beer.

          Comment

          • kc8adu
            Super Moderator
            • Nov 2003
            • 8832
            • U.S.A!

            #6
            Re: Pyramid 7" LCD - No stable picture

            had an icom ic-2800h in with that same washed out mess.
            it was a dc-dc converter bad.it was supposed to supply -15v.it was at 0.

            Comment

            • Wizard
              Badcaps Legend
              • Mar 2008
              • 2296

              #7
              Re: Pyramid 7" LCD - No stable picture

              Exactly, that why need to check all the voltages. One might show wrong as well as bad caps.

              Cheers, Wizard

              Comment

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