I'm relatively new at electronics repair with little experience, and have a difficult problem. Posted at a couple other sites and have not had much help.
I have an Akia 200watt SMPS that I have partially repaired. The supply powers a 27 inch lcd tv display. Originally it had 5v standby power only and would not turn on. Almost all of the low voltage output capacitors were domed and leaking. I replaced all of the output caps with new low esr, high frequency caps of the same voltage and capacitance. Both main filter caps were replaced also as a precaution.
The display now functions properly. 5v, 12v and 24v outputs appear good.
Unfortunately, the supply has a noticeable buzz coming from both PQ3220-1000C transformers when turned on. Annoying to the point that the set is not usable. I do not know if the supply buzzed prior to the cap failure since the unit was given to me dead.
Perhaps the bad caps caused damage to other components?? I see no other visible damage. I have checked almost all other components in circuit (to the best of my ability) with a digital VOM and cannot find any bad components.
Suggestions are appreciated. Not sure what to look for next. I'll attach a picture of the supply. Schematic is avialable here: http://www.turuta.md/PSU/LCT-2016.pdf
I have an Akia 200watt SMPS that I have partially repaired. The supply powers a 27 inch lcd tv display. Originally it had 5v standby power only and would not turn on. Almost all of the low voltage output capacitors were domed and leaking. I replaced all of the output caps with new low esr, high frequency caps of the same voltage and capacitance. Both main filter caps were replaced also as a precaution.
The display now functions properly. 5v, 12v and 24v outputs appear good.
Unfortunately, the supply has a noticeable buzz coming from both PQ3220-1000C transformers when turned on. Annoying to the point that the set is not usable. I do not know if the supply buzzed prior to the cap failure since the unit was given to me dead.
Perhaps the bad caps caused damage to other components?? I see no other visible damage. I have checked almost all other components in circuit (to the best of my ability) with a digital VOM and cannot find any bad components.
Suggestions are appreciated. Not sure what to look for next. I'll attach a picture of the supply. Schematic is avialable here: http://www.turuta.md/PSU/LCT-2016.pdf
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