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Question:

We had a voltage spike of over 250V now the tv does not work,have checked the fuse it is ok.any ideas?

I have looked at the circuit board looks fine.Is there a commen component that gets burned out?

Answer:

Have a tv repair shop demagnetize the picture tube. It may be an easy fix. Then again, it may not.
Sounds like it blew out a circuit or a resistor or a diode.
depending on the model of the set-a thermo trip or voltage regulator may have been activated most tv's have these built into their power supply units as safety features-also check the 20 millimeter fuse/s on the power supply board-if something had burned out you would smell it.
The spike happens too quickly for the fuse to go open but transistors usually fail before the fuse , it is common for the surge resister usually a 5 watt and 4.7 ohm , these resisters don't burn or discolor so yo need a multi meter to check it ! Oh and if you follow the wires from the degauss coils that are around the tube bowl to the circuit board there will be a device with 2 or 3 legs close by , feel at it and if it is hot then it means that the mains fuse, the on/off switch and the mains cord all good , Oh well I don`t want to write a full length novel on it so that should get you started so good luck . PS do all this with the set switched off of course !!

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