ONAN generator are nice but Propane Generators suck a lot of propane. And they are often bigger than you truly need.. My ONAN has, on occasion, powered not only MY RV, but my next door neighbor's as well, (And even my sticks and bricks though not fully) Now there is an advantage to more generator than you need, but still, costs more money too. And ONANs are not inexpensive either.
For JUST the TV's you can likely get by with a Honda EU-1000i, this gasoline sipper puts out around 800 watts full time (1000 peak and yes I am seriously rounding) but for TV only you can likely get by with half that. IT IS NOT big enough to power a converter over 45 amps though.
A Yahama EF-1200I, will power a 60 amp converter with power left over.
What I would recommend is a Honda EU-2000i Companion, the Companion is easier to connect up to an RV, and.. If you find you need more power still, You park a standard EU-2000i beside it and you now have 2x the power, a full 30 amps in fact.