68kMLA Classic Interface

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Lc ii no sound
Posted by: imactheknife on 2023-02-13 12:29:32 So, bought another lc ii on the weekend. Beautiful shape. No sound from get go. Did the usual, pulled old caps, washed board, prepped everything and put new caps on. Board works beautifully but still no sound. Pull dfac chip and the little 78L08a chip and cleaned. Still no sound. Any ideas?
Posted by: joshc on 2023-02-13 12:47:10 Any sound if you plug headphones in? Have you tested the speaker? LC II caps leak super badly - everything in that area may need to be cleaned/reflowed. Last time I did one of those, I just lifted everything in that corner of the board and resoldered it all. UC9 is part of the sound circuit, the 34119 IC: Here's the sound schematic:
Posted by: imactheknife on 2023-02-13 13:00:13 Any sound if you plug headphones in? Have you tested the speaker? LC II caps leak super badly - everything in that area may need to be cleaned/reflowed. Last time I did one of those, I just lifted everything in that corner of the board and resoldered it all. UC9 is part of the sound circuit, the 34119 IC: View attachment 52332 Here's the sound schematic: View attachment 52333 Cool, thanks josh. No sound from headphones either. I will pull those and clean and post results!
Posted by: imactheknife on 2023-02-13 13:37:48 Yeah those were nasty
Posted by: imactheknife on 2023-02-13 14:49:52 Nice.. well, progress?
Posted by: imactheknife on 2023-02-18 10:52:30 Well, completely pulled off all caps, and ic chips in that area. Cleaned, and checked all traces. No dead or broken traces. Put all back on and she works. So maybe something was just not 100% connected. Also reflowed egret so maybe that helped too
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