Resolved SE 30 screen: one column out of 8 is dead

Discussion in 'Apple Collectors' started by Enric, Sep 29, 2013.

  1. Enric, Sep 29, 2013
    Last edited: Oct 6, 2013

    Enric macrumors newbie

    Joined:
    Jul 30, 2013
    Location:
    Geneva, Switzerland
    #1
    Hi everybody,

    Someone gave me a SE 30. It boots fine but the screen displays a black columns exactly every 8 pixels:
    se30_deadColumn.jpg

    Also, the sound was very weak. There was some capacitors leaks (not too serious). I replaced all capacitors and the sound went back, however, dead columns remains. I tried cleaned the ram modules. The mac comes with 2 set of 4 rams. I tried using only one of the two set in the first memory slot but this did not fix the problem.

    I noticed a wire near the center of the board that bridges a chip pin with a another point:
    se30_logic_board.jpg

    I look around for some SE 30 pictures over the web and did not see such wire on other board.

    Any idea is welcome!
     
  2. gkarris macrumors 604

    gkarris

    Joined:
    Dec 31, 2004
    Location:
    "No escape from Reality..."
    #2
    If i remember from servicing those back in the day the screen bars is caused by some CRT board...
     
  3. tdiaz macrumors 6502

    Joined:
    Feb 7, 2006
    #3
    Swap the SIMMs around. See if the issue moves.
    Or the machine crashes. It's supposed to check RAM on startup, I find that doesn't always detect bad RAM.
     
  4. MacTech68 macrumors 68000

    MacTech68

    Joined:
    Mar 16, 2008
    Location:
    Australia, Perth
    #4
    Check around the capacitor circled for etched tracks (they'll look black).

    Also check tracks from the 4 74F253s have continuity to somewhere. These are the multiplexers for the video RAM. Broken/etched tracks to these 4 could be the problem, caused when C7 leaked.

    It's also possible that one of these tracks goes underneath C7.

    The prototyping wire might be a fix not present on all boards OR a factory repair for a bad track.
     

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  5. Enric thread starter macrumors newbie

    Joined:
    Jul 30, 2013
    Location:
    Geneva, Switzerland
    #5
    Fixed!

    Fixed! thanks for advices.

    It was quite tricky figuring out where the tracks go underneath the chips. I first identified the good ones, which allowed me to deduce the bad one.

    mac se 30 bad track_s.png

    Fixed it with with a quite thick wire. I am not a pro at soldering but I improve myself...

    mac se 30 logic board fixed_s.JPG

    And here it is!

    shuffle_puck_s.JPG
     
  6. MacTech68 macrumors 68000

    MacTech68

    Joined:
    Mar 16, 2008
    Location:
    Australia, Perth
    #7
    Pretty good job if you ask me!

    Shuffle Puck Cafe! ;)

    Well done! :)
     
  7. gkarris macrumors 604

    gkarris

    Joined:
    Dec 31, 2004
    Location:
    "No escape from Reality..."
    #8
    Oh, for the simple days of computing... :D
     
  8. David Schmidt macrumors 6502

    David Schmidt

    Joined:
    Aug 22, 2006
    Location:
    Southeastern USA
    #9
    Exactly so. And the personal satisfaction of knowing you made the machine work like it should... priceless.
     
  9. Enric thread starter macrumors newbie

    Joined:
    Jul 30, 2013
    Location:
    Geneva, Switzerland
    #10
    That says it all.
     
  10. havokalien macrumors 6502a

    havokalien

    Joined:
    Apr 27, 2006
    Location:
    Kelso, Wa

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