tv on the fritz, need help

[Guest]

Model 30pw850h37a, chassis em1.2u aa, Turn on tv, screen is almost black with a dark purplish hue, if up close to tv you can see the outline of words and pictures but nothing is clear or visible. Sound is perfectly fine. After listening to the news for 5 hours with no picture all of a sudden out of nowhere the picture can back. Obviously there is a problem somewhere that is going bad. I have tried to find a repair man in the area other than best buy but all #'s are disconnected if someone could please help me and point me i n the direction of what is going bad I would greatly appreciate it. This tv is only 3-4 years old. And thanks in advance.

[gilloz]

There are a few things you can try, as simple or maybe dumb as this may sound. First, it could be a heat related problem or a cold solder joint. With the back off the TV, use a long plastic or wooden probe and carefully wiggle the wires on the circuit board around the neck of the picture tube while watching the front of the TV with a mirror. You can tap on components on this same board and on the motherboard around the video amplifier circuits. If you don't have a layout of your motherboard, just poke around lightly tapping components to see if anyone of them will cause the picture to come back. Simple, I know, but it has worked for me in the past to find cold solder joints on power ceramic resistors and various components. You can also apply pressure to the motherboard as if you are bending it downward to warp it and see if any particular area affects the picture. Be aware of the High Voltages in and around this area. Use only one hand at all times. good luck