1. Join Now

    AVForums.com uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Help!: Hold Down Deflection LED lit Barco Horizontal Board

Discussion in 'Projectors, Screens & Video Processors' started by cosaw, Sep 23, 2005.

  1. cosaw

    cosaw
    Active Member

    Joined:
    Jun 14, 2003
    Messages:
    753
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    31
    Location:
    Stockport, Manchester
    Ratings:
    +19
    Hi all

    I have a Barco Data 500 with a fault. (The 500 has the same chassi as 800 but smaller tubes and lenses.)

    The symptoms of the fault are evident in the picture as a loss of stability with the width of the picture pulsating gently but fairly rapidly as though ready to collapse in on itself. (This possibly affects the height also though difficult to tell).

    The Red Hold Down Deflection LED on the Horizontal board is dimly lit which suggests the voltage too it or on it is too high. The machine does NOT go into Scan Fail though and all other LEDs seem normal.

    What have I tried? Checked the +17v ref point on the smps and it seemed ok at 17.2 so left it. Tried a different PSU and Convergence Board that I have spare but no difference. Turned to minimum the master width pot on the smps - no difference. Also turned to minimum the width limiter pot on the Horizontal deflection board itself - no difference. Most importantly tried a different Horizontal Board - the pulsating is less but still evident and the Hold Down LED is still lit on this alternative board.

    Where do I go from here? Anyone any idea of possible causes to my problem.

    Thanks in advance,

    Simon
     
  2. Boy Lex

    Boy Lex
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    Eek! Sorry to hear probs mate. Stupid one as I'm sure you've done this, but have you tried different sources?

    Also I'd look at some of the ribbon cables - if you're daring give them a wiggle and see what happens. One of my seleco 350s (sheesh - must find a home for them!!!) had the width jump in and out on me and it turned out to be a dry joint on a ribbon cable connector.
     
  3. cosaw

    cosaw
    Active Member

    Joined:
    Jun 14, 2003
    Messages:
    753
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    31
    Location:
    Stockport, Manchester
    Ratings:
    +19
    Different sources - yes done that. Not examined cables yet but that will be the next step after trying other boards. Managed to get a few spares off the net. I seem to be slowly excluding the boards it isn't. Dry joints on the motherboard would be a nightmare as would mean stripping the machine totally to bits as far as I can see - lets hope its not that.

    The search continues - slowly!
     

Share This Page

Loading...