His issue with the second board has to be the sound chip,
both were re-caped by me.
the first recap went well, (on the LC-2 board with no sound)
after the sound did't work, I went back over my work and re-did a bunch of caps. I used a continuity test on the traces.
Didn't find any issues, however the extra heat, caused me to lift a couple pads, and caused a bunch of extra work for my self,
I even hand ran some wire wrap from caps to proper VIA's, but still no sound,
rest of the board works fine, He said before this board was a No Boot, No bong.
my guess is someone put this board in the dishwasher , ran a cycle, and then powered up the board with out fully drying off all the chips properly,
in turn cooking the sound chip some how.
the corrosion build up on this second board with no sound was substantial, i used my dental pick for about 45 minute scraping white chalky build up between the IC pads, The sound chip had the most corrosion/build up between the pads.
out of all 7 boards this one (LC-2 /w No sound) I spent the most time with. Because i had to change modes, Re-Cap mode to troubleshooting mode, then to process of elimination mode, then re-cap mode again…..
I would say the macintosh portable board took the second longest, lots of caps
that one turned out pretty darn good. And works good too
(I hear)
