Apple Lisa 2/5 defective Video Output?

[bibilit]

Worked on the Lisa board yesterday, removed the I/O connector (a lot of mess from the battery) a lot of traces were not there anymore, so spent part of the day fixing those (have not tested anything yet, but here are some pictures for reference)

I have left indicators on the blue paper for reference, 1 goes to 1 and A to A... will let you know once tested.

 

[MarNo84]

OMG! Wow - good job ;D  Well, for my serial connections, I assume I have to do the same...- besides my connectors/slots didn't look that much corrodet. What did yours look like? Have any pictures? I will swap the small parts and report back ...I don't want to remove the slots }

 

[bibilit]

Didn't look bad at first, but most of them were not connected anymore.

 

[MarNo84]

JUST A QUICK UPDATE: it's alive and running again [ ] 
I finally found the bugger...it was just a broken trace between the lines R1 to C15/R15. I measured every part and trace again and finally found a missing signal - so d*mn easy at the end - no parts needed to swap,

Did a quick solder work on that broken trace and everything works like a charme again  :lisa2:

The last steps / work to do will be the still cut serial connectors. That's a lot of wirework to do - I will rethink about that - no one needs serial connectors on their LISA? Everything was cleaned and neutralized - so no future damage. Well, I think this is done - any future updates will come here on the forums and on my repair blog / on my homepage and yery soon on my YT channel too - especially that complete repair process was recorded on every important step. Soon I will upload a special repair video on my channel as well.

Thank you all for your assistance and your helpful advices :wub:

 

[mactjaap]

What a great story and happy end! Please post a link to your YouTube video if ready. I'm looking forward to see it. That you found such a small trace defective is impressive.

 

[bibilit]

Happy ending for me as well :





Still a problem with the I/O but i have got video.

 

[MarNo84]

Yeah  :lisa2:  great job done! Actually I bought me two motherboards from eBay - they look very clean and in nearly perfect optical condition (untested). Especially one board has the original Lisa 1 / 2 Mouse port - my Lisa 2/5 board already has the "modern" port, so I will swap my motherboard too I think I will keep that repaired board maybe..just as an example/spare and give the other good board to my friend in exchange. Hmm, I will report back when they arrived at my door.

 

[MarNo84]

Final Update:  I also did repair every left bad trace on this motherboard - I also did the first wireowrk again - now it looks better, more professional After I tested everything again, I did use some Urethan 71 (plastic based isolating lacquer) to finish and safe the polished traces from future corrosion.

...and the funny thing is - after all these weeks of adventuring work on this motherboard - I got me 2 other motherboards on eBay one is in nearly perfect condition and works like a charm but the other one is a little bit messed up with uncleaned battery leakage on the slots and connectors. It's already in a cleaning bath with lemon accid  the good / awesome thing on the uncleaned one:  it seems to be an original LISA 1 board with it's original metalframe - it has still the original writings and symbols for each port - especially the beautiful mouse port this means some exchange with my actual metalframe and motherboard xD