68kMLA Classic Interface
This is a version of the 68kMLA forums for viewing on your favorite old mac. Visitors on modern platforms may prefer the main site.
| Click here to select a new forum. | |
| Performa 400 Battery damaged Logicboard Repair | |
| Posted by: max1zzz on 2020-09-05 04:03:17 A little while ago I brought a ago I brought a Performa 400 on eBay with battery damage, today came the day to try and get it going again First ting was to clean the battery residue off the board, this was done with vinegar and a lot of scraping, then washing in water to remove the vinegar, then washing in IPA to remove to water. I didn't get any pictures of this but after this cleaning the board actually powered up and produced a picture! However all was not good, looking at the bard there was some clear damage to the scsi traces  A closer look reveals a almost perfect slice through the traces along the edge of where the battery holder used to be  OK, doesn't look too hard to to jump those breaks, First scrape the traces  While doing this I found another trace break, No problem, that should be easy to fix, Just have to solder some fine wire across all the damaged traces  At this point it got a little more complex than I intended, It turns out the via shown in the last picture was not attached to anything beneath it and it promptly floated off when I tried to solder to it, Time for a nice long bodge wire to the other side of the board! followed by another two when some gentle probing revealed a further two via's nearby also no longer existed The other end of those bodge wires  A couple more jumpers  At this point I thought I had all the traces fixed, So I plugged it in and fired it up.... To a Floppy disk icon, damn. Looking again I found another damaged trace, this was repaired, but still no luck. At this point I started scraping the tops of any via that looked slightly dodgy and found this:  Yep, that'll do it. One more long bodge wire to the other side of the board....  We have SCSI! (Also this 40mb quantum drive I got in another LC II recently also seems to work 🙂 ) Now just to coat all those connections with solder resist to stop the wires getting ripped off the board  And the bottom of the board:  Now the board just needs a recap and a full test. Something tells me this board will have audio issues....  | |
| Posted by: davidg5678 on 2020-09-05 09:25:10 Impressive work! I have yet to get one of my battery damaged boards to work, despite having the tools and soldering skills. One day... | |
| 1 |