Upon opening this TV set, I scanned the PC board with the naked eye and soon enough, I found a bulged 1000uf/35 volts capacitor in the power supply primary section. I replaced this capacitor and turned the TV on. A few seconds later, other 1000uf/35 volts on the same line, blew up. I unplugged the set from the electrical outlet and touched the first capacitor that I installed and realized it was very hot which gave me the indication that these capacitors is getting more than 35 volts on that line and that is why, it blew up.

I started tracing the line of this capacitor and I found a fuse resistor open that connects directly to the fly back section. Replaced that fuse resistor and did some checking in the fly back area but everything checked out fine. Based on this checking, I started tracing the line backwards to the power supply and stated doing some checking there.

There was a leaky transistor A1015 in secondary section of the power supply. This faulty transistor was the main reason that made that capacitor to blow up. I replaced the transistor and turned on the TV set and I could see a nice picture but there was no sound.

I checked to make sure that all the speakers’ wires were connected in the sockets. Both speakers were checked with the ohm meter and all gave good results. There was one more thing to be checked, the audio IC. The AN17821A was getting hot and the reading on that IC was lower than usual. That is an enough reason for me to change the IC. This IC was pulling the voltages down because one or two legs of the IC were shorted out. I replaced this IC and the sound came loud and clear.

I hooked this TV set to my satellite receiver and tested it for an hour or so and it worked nicely. I was really impressed with the picture on this set. Although it was a Chinese made and sold cheaply, it was a very nice set.

About

10 years of practical electronics. owner and operator. I service the Bethlehem area in Palestine. I repair Xbox 360 and all play stations and modify their power supplies. also repair lcd and Plasma tv sets, and lcd computer monitors. I have a degree from Bob Jones University in general business and one year degree in Industrial electronics. a intensive course in Media. I also work as a camera and audio man as a free lancer. Also great experience in video editing and installing surround systems for home and movie theaters.

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