Television and Home Theater

I have a 27" GE that powers up fine.....after a few minutes there is a loud popping sound from the back of the unit....also a white spark can be seen from the coil on the back of the tube.....sometimes the sound stays on but no picture.....then the screen comes back alive......sometimes the whole TV shuts off then turns itself back on......any help with this would be greatly appreciated....thanks in advance.....

converge lines across tv won't adjust. getting curving wave from above screen waving down. need help.

I have a 7 year old Mitsubishi projection TV. About a month ago it the picture started changing. When it has been off for a few hours the picture is very dark for about 30 minutes. After that time the picture is once again very good. What can be the cause of this???