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Mac 512K chime but no video (buzzing/ticking)

Posted by: elemenoh on 2020-03-11 16:30:15 This 512K is chiming, but doesn't show any video. 5v/12v rails test okay. Swapping in a known-good analog board resolves the problem. A faint high pitched buzz and ticking can be heard, but it's hard to tell where it's coming from. The best I can tell is that it's coming from T3, but could be wrong. T3 also has a blob of smelly black something on it, but other working ones have all sorts of weird goo on them. Dead Mac scrolls indicates this sort of issue might more likely be the flyback transformer. Is that the most likely culprit or should I look further at T3/elsewhere? View attachment IMG_1712.mov

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