Panasonic PT-47WX49 47" Rear Projection Television Logo

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Question about Panasonic PT-47WX49 47" Rear Projection Television

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Power supply Hi, I took the power supply board out of the tv went home and pluged into a variac tried to measure some voltages from test points. But I could not measure anything at all. It was working while in the tv. I then traced the voltage started from where the ac goes into the board.On the white wire and it's related components always measured 7v and the black wire side goes to the fuse and all componets always measured 105v(or whatever I cranked the variac up). There's a varistor between the white/black wire.I am not sure it's good or not. My question is whether it is correct to take the board out and do service as it may not be grounded correctly. Any advices are much appreciated. Pete

Posted by peter wong on

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1 Answer

Anonymous

You are so lost... a short in anything after the power supply will shut down the horizontal driver signal. first check to see if horizontal output transitor is shorted. If not it should have about 110 volts dc on it. if not go back to Power suppy ...many things start here...check to see if you micros got power a 5v heatseeked regulater is common bad. also the startup circuits can be tricky...in the power suppy. I look for a kit online for power supplies ...they give you about every that fails. or you can start buying boards...best bet it is take to a professonal for you my freind havent a clue. CrazyLarry

Posted on Jun 27, 2007

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