Tv turns off after 5min,1-2 hrs

This will sooner or yet later get worse as time moves forward why?

You have a power supply unit gone bad in this TV.. The reason why I know is this the capcitors I call caps would look swollen and would heat up to a point that the TV just looses power as the capcitors cannot hold any charge anymore as they are defective. If your SAVVY you can discharge the TUBE and fix the PSU buying the capcitors online and soldering them yourself on the power supply unit. check this website out for reference on how Caps look www.badcaps.com open up your TV and see if you got bulging caps if you do that is a major issue and it would need replacment. Thanks for using Fixya.com hope this helps please rate!!