Re: 32" Goodmans TV
I'm convinced that the flashing is not an error code, merely a symptom of a bad PSU. Try using a small low-current 3mm LED on the STBY_ON_OFF pin; it might be bright enough to see it flashing on and off. In which case, the CPU is shutting down the PSU, possibly because the rails aren't good enough. (That's what the PROTECTION_DETECT circuit does - undervoltage protection.)
One thing that I heard about poly caps is they are very temperature dependent and they can heal when they are damaged, but they do lose a bit of performance in the process (usually in the form of capacitance.) It could explain the problems we are getting. The two caps, near the big transformer, C877 and C878, carry the *full* load of the PSU on alternate half-cycles so they are under a *lot* of stress. The peak current through those caps is probably on the order of 5A. They're quite expensive too - Digikey has them for $1 each - and manufacturers are always under pressure to make products cheaper, so it wouldn't surprise me if these are sub-par caps. Another form of bad capacitors, but not electrolytic, and there's not much you can do as there aren't really "good" poly cap brands unlike with electrolytics.
Originally posted by dumpystig
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One thing that I heard about poly caps is they are very temperature dependent and they can heal when they are damaged, but they do lose a bit of performance in the process (usually in the form of capacitance.) It could explain the problems we are getting. The two caps, near the big transformer, C877 and C878, carry the *full* load of the PSU on alternate half-cycles so they are under a *lot* of stress. The peak current through those caps is probably on the order of 5A. They're quite expensive too - Digikey has them for $1 each - and manufacturers are always under pressure to make products cheaper, so it wouldn't surprise me if these are sub-par caps. Another form of bad capacitors, but not electrolytic, and there's not much you can do as there aren't really "good" poly cap brands unlike with electrolytics.
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