Picked this TV up as a freebie today. The backlight is flickering quite badly immediately after powering on, and eventually dies completely after a minute or two. First thought is the obvious - caps.
Stuck my scope on the two biggest caps in the TV (82uf 450v), and I'm getting around 150v of ripple on them! DC voltage is measuring around 389v across those caps, which are paralleled. I soldered a 120uf 450v cap across one of them, and it didn't help the flickering at all.
Suggestions? Not hard to replace all the caps, but I'd have to order and wait for good caps or install the cheap general purpose caps available in local stores. I've also seen some threads on similar Samsung TV's involving shorting an optoisolator and changing resistor values or something, but I can't find that again.
Power supply board is BN44-00264A rev 1.4, btw.
Stuck my scope on the two biggest caps in the TV (82uf 450v), and I'm getting around 150v of ripple on them! DC voltage is measuring around 389v across those caps, which are paralleled. I soldered a 120uf 450v cap across one of them, and it didn't help the flickering at all.
Suggestions? Not hard to replace all the caps, but I'd have to order and wait for good caps or install the cheap general purpose caps available in local stores. I've also seen some threads on similar Samsung TV's involving shorting an optoisolator and changing resistor values or something, but I can't find that again.
Power supply board is BN44-00264A rev 1.4, btw.
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