It would help if you displayed the year, make and model of your rig in your signature line so others will know what RV we're discussing here.
Do you have an inverter... and if so... is your television system plugged in to an outlet powered by the inverter? Typically, I believe the TV is on a circuit powered by the inverter and it should work.
As for solar, if you have only the factory mounted 10w panel on top of the coach it won't really provide you much help.
Best of luck.
Rick, Nancy, Peanut & Lola our Westie Dogs & Bailey the Sheltie.
2007 Itasca Ellipse 40FD