Television and Home Theater

My big screen turns on, but there is no picture and sound. Would like a new tv, but can't afford it. Would like to fix the one I have. I have checked all the fuses and they are all good. Does anyone know how this set can be fixed. Thanks for your time. Hope to here from someone soon.

HELLO,
IM HAVING PROBLEMS WITH MY RCA BIGSCREEN IT HAS A BOW AT THE TOP AND BOTTOM. RAINBOW COLORS AROUND THE OBJECTS IN THE PICTURE. CAN ANYONE TELL ME WHAT IT IS THAT NEEDS TO BE REPLACED AND WHERE TO FIND THE PART? IF I NEED TO ADJUST SOMETHING HOW DO I? I WOULD LIKE TO FIX IT MYSELF IM PRETTY GOOD AT FIXING THINGS I JUST NEED A LITTLE HELP FINDING THE PROBLEM AND WHERE TO GET THE PARTS
THANKS, SHAGGY

please can someone help. i have an lg plasma and have noticed three green vertical lines running down the laft side of the screen. But today when i put the tv on a thick black line down the right side of the screen appeared. has anyone any ideas whats wrong with it.