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Trying to revive my Mac SE with exploded battery

tobiasvogel

New member
Hello everyone,

I got ahold of a Macintosh SE some time ago and I know it was in working condition when I got it. I stored it away without removing the battery at that time - I know, my fault.
When I brought it out again few weeks ago I found that the battery had exploded and the board was heavily corroded.
Now I am trying to revive this thing. I have desoldered the comoponents in the area of the battery, replaced resistors and caps where needed and thoroughly cleaned the board.
I am now presented with this screen.
I have checked pretty much every solder joint with a multimeter and I am kind of lost here, maybe someone could point me to the right direction? Has anyone come across this problem?
The fan starts and I can hear a crackling elongated beep that wouldn't stop until I cut the power.

Thanks,
Tobias
 

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tobiasvogel

New member
Yes, at least for the obvious ones that were easy enough to see without the comoponents that I removed.
Do you think it's some broken traces?
 

tobiasvogel

New member
Sure. I decided to put in a connector instead of a new battery (held in with double sided tape) and have the batteryholder with the battery stuck to the case (with double sided tape as well) since there was some nasty residue right beneath the old battery and the original battety terminals on the board didn't make a good contact anymore, in case you are wondering.
Also I socketed many of the ICs where there was corrosion from the battery.
 

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Some of those traces/vias look pretty sketchy to me. When you say you checked them, do you mean visually or with a multimeter in continuity mode? I would also verify continuity for each pin on those ICs with corroded legs. Yes, it's painstaking, but necessary. I think schematics for the SE board are available. Alternatively, when I was repairing traces on an LCII board, I found sanded-down images online that made it easy to see what connected to what...don't know if similar images for the SE are available. Unfortunately, battery bombs are usually bad-news.

Also, recapping/reflowing the analog board and PSU is usually a good idea for this system. I don't suppose you have a known-good analog board/PSU you could use to eliminate that variable? :)
 

tobiasvogel

New member
I did go over the traces and pins with my multimeter. When it comes to schematics I have the "Bomarc" ones (I don't know if there are any other schematics out there).
Maybe I don't know enough about schematics, however, they seem to be missing some capacitors and I also don't really understand why some of the IC pins are left out (e.g. pin 10 on the sound chip - I assume that pin is simply not connected?).
You are correct, I don't have any spare analog board / PSU to hand, so I can't say for sure if they are working.
I'll be going over the traces again on the weekend, maybe I have missed something.

BTW: Worst case I couldn't fix it; I found the thread of this guy Kai Robinson who aparently tried to recreate the logic board of a Macintosh SE, does anybody know about the state of that project?
 
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