It's very unlikely that you will need anything other than what you have in your coach now. Assuming you have a new flat screen digital TV in your coach you should be able to get whatever they have coming in.
First of all, you have to ensure that the power supply to your over the air antenna is turned off as this is also where your cable connection comes in. On you get OTA TV. Off you get cable.
Second, when you do a channel scan on your TV there will also be an antenna type selection and you need to change this from Antenna to Cable before doing a new scan.