Newjohn You need to set both your antenna booster / cable switch (was on wall behind passenger seat on my 15 Ventana) to "Cable", AND set you TV input to Cable. If you still don't get all the cable channels expected you might take a look at the quality of the cable connector on the RV park stanchion. In many cases I found the connector pretty worn and had to get it replaced oe put a slight bend in my cable center conductor to get a better connection.
2022 Dutch Star 4369 (on order)
2015 Newmar Ventana 4369 w Hydralift