Originally Posted by Paco6048
Apparently you have nothing but a smart answer reply.
Ok Paco6048, here's a less that "smart" answer for you. Assuming you are placing the super antenna on the roof of your RV, a very good, high quality, VHF/UHF antenna is going to be marginal, at best. With the high quality antenna 12' to 14' high along with a high quality amplifier, signals may still be marginal given the surrounding obstructions and weather conditions between you and the transmitting station(s).
Your best bet would be to elevate the antenna to at least above the tree line in order to receive quality signal within a reasonable distance ( 30 - 50 miles ). Otherwise, a satellite system, with clear site of the sky is your best bet.
Now, to answer your original question ... attaching the TV antenna to your cable input should work just fine if you have a digital ready TV.