flip@osu-cgrg.UUCP (Flip Phillips) (05/24/86)
*** REPLACE THIS heat sink connection WITH YOUR own wire ***
Well, after a month or two of my mac's video going intermittently on and
off it finally bit the big one.
Only the video would fail, the machine would still be up. Light tapping
usually gave me back the video. I assumed an heat related intermittent
connection. I took the back off, took all of the connectors on and off,
jiggeled them around, it came back for a while but this morning it bought
the farm.
Well, i took it to our resident hardware guru here and we disassembled the
board and noticed a transistor whose heat sing was causing the problem
(Q11). Carefull inspection on the trace of the board showed that the
collector wire was just shived through the board! No solder, no trace to
connect it to. Odd, we thought, but then we noticed the heat sink which
has the transistor pop-rivited (Come on!, 2cents for a screw, bolt and a
few star washers!) the heat sink was connected to a pad on the board.
There seemed to be no cream behind the transistor either. A simple piece
of wire soldered from the protruding collector wire to the pad has solved
the problem.
Just thought all of you would like to know...
(BTW, my mac is one of the very originals, bought like 30 days after
intro... maybe, just maybe, they have re-designed the analogue board a
bit,)
flip
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Flip Phillips {ucbvax,decvax}!cbosg!osu-cgrg!flip
Computer Graphics Research Group, The Ohio State University