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View Full Version : LED Storm Repair Log



VectorGlow
10th May 2009, 09:22 PM
Symptom: One layer of background graphics corrupted/repeated vertically and some bit shimmering
Cure: Did a bit of prodding around on the lower board and found that touching a group of pins on the surface mounted (64 pin 1mm flat pack) 23C4000 caused the shimmering problem to change a bit. Isolated the fault to pin 31 on that chip which is A5 (an input with no signal) and checked where it should be coming from (pin 13 of the PAL at location 1K). The trace between these two points had been severed by an extremely tiny bit of corrosion where the track met a plated through hole. Fixed this and all was well.