jkirsh@contact.uucp (Joel Kirsh) (03/10/91)
My almost-two-year-old Mac plus has recently developed intermittent "black- outs" (maybe I should be crossposting to sci.med? ;-) ) The entire display goes black, but returns with just a slight tap of the casing. Anyone seen this before? Is it my entire display that's trashed, or just a flakey connection here or there? Am I about to be electrocuted by an improperly connected flyback transformer? Any and all advice welcome. Joel
lrobin01@nexus.bison.mb.ca (Lane Robinson) (03/15/91)
jkirsh@contact.uucp (Joel Kirsh) writes: > [more] > My almost-two-year-old Mac plus has recently developed intermittent "black- > outs" (maybe I should be crossposting to sci.med? ;-) ) > > The entire display goes black, but returns with just a slight tap of the > casing. Anyone seen this before? Is it my entire display that's trashed, > or just a flakey connection here or there? Am I about to be electrocuted > by an improperly connected flyback transformer? > > Any and all advice welcome. > > Joel Okay, most likely the problem is a connector on the inside labeled J4. Check pins 1 and 3 for cracked solder joints or tarnishing. Resolder those two points anyway. If you try it out now and it still doesn't work, then pissibly the white and orange wires of the analog board to logic board have lost continuity, check that. Possibly the pins inside J4 and J7 connectors are just tarnished, you can buy stabilant and treat the connectors with it. You want to retard [more] corrosion and lower electrical resistance. An electronic supply outfit would be able to help you with buying the right thing. Because you said that when you tap it, it comes back, I put my money on the connector J4 needing a resolder. I do servicing for Macs and that's the single most common fix I do for them. Lane Robinson Winnipeg, Manitoba, Canada P.S. I tried to email you directly, but it bounced. I also add in the obligatory disclaimer to say that I am not responsible for anyone damaging their computer and/or getting an electrical shock. Be warned, tread lightly, wear gloves if possible, and stay away from any lightning bolt symbols. _______________________________________________________________________________ Reply to: lrobin01%nexus.bison.mb.ca@niven.cc.umanitoba.ca
consp22@bingsuns.cc.binghamton.edu (Darren Handler) (03/15/91)
Most likely, the constant heating and cooling of the power supply has caused
the solder joints on the analog board on the connector that conects the
alalog board to the logic board to crack.
If you are daring, open up the Mac and take a look. The same thing happened
to me, I resoldered some joints and it works fine.
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Darren Handler - Senior Computer Consultant - SUNY Binghamton
consp22@bingsuns.cc.binghamton.edu
Academic Computing Support - The most fun you can have sitting down
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