What i do is bring along an TV TEE adapter and a second 12-foot RG cable... Then I hook up the tee adapter to the pedestal at the camp ground and run my main RG cable from the pedestal to the CABLE TV jack on the outside of the trailer. the second RG cables gets hooked up to the tee and thrown under the trailer so i can grab it on the other side in the patio area...
This way I can hook up the outside TV to the cable that is under the trailer...
Works great for us and I have never seen degradation of signal strength using the TEE adapter...
Roy Ken