In the standby mode the primary side of the power supply makes a buzzing noise. The p.s. drive signal is broken up. Nothing burns up but is annoying. When the set is turned on everhthing works fine. The power supply is quiet and the picture and the sound is normal. SAMS 4975
In standby it sounds like a broken up zzzzt Know what I mean?
Patio, your problem is a lose transformer winding or a singing coil. in some cases, that buzzing sould is also an idication that there is a capacitor in the SMPS0- PWM circuit, that is going bad, and I have seen a simple thing like this cause major breakdowns as well as burnouts. I would unplug the set, get an ESR type capacitor meter and start from the beginning of the power supply and go from there and make sure you have no leaky capacitor. if you can locate the singing coil, if thats what the problem is, Sometimes you can eleminate the noise by siliconing the coil and pushing in the glue tight into the coil, but you must let this completely dry befroe using the set. Good Luck, and please let us know how you made out.
Larry , I talked to the customer and he told me that the set has been shut off and down his basement for two years. So I let it make the noise and two days later the sound gradually went away all together. Must of had moisture in it and was arcing. Thanks for the input Tom Patio T.V.
Yeppers, strange but things like this happens all the time.
IIRC, that particular model has either a Konka or DLK chassis in it. Not exactly top of the line engineering. They also had PS problems in those with the regulator drive IC. Noisy switch mode transformers in the cheaper line sets is not uncommon.
Thanks for the reply and the input. Tom Patio T.V.
Would the ps also cause a vertical sync problem?