won't stay on

[oldodar]

50 inch tv won't stay on. it takes 30 to 40 minutes before it finally stays on. what is the problem with my t.v.

 

[americanaudiophile]

First guess would be power supply. Replacement boards may be available depending on the model. A tech may be able to repair the board. A common problem is bad capacitors which are often rated at 85 degrees instead of 105 degrees. A bad capacitor can be leaky or look like a puffed up cylinder.