Joseph the first thing I would recommend you do is look at the owner's manual for your TV and confirm that it is equipped with a "ATSC Digital Tuner". The use of the term Digital TV has been abused by some TV manufacturers. Your TV may be a Digital Capable TV, which means that it needs a separate ATSC Digital Tuner to acquire a digital signal.
Once you have confirmed that your TV has a ATSC Digital Tuner, the problem sounds like your TV is not receiving a signal. This could be due to several factors, problems with cabling in the RV or the need to amplify the signal you are getting so the TV can acquire it.
Take a look at the answers I gave to the questions below, they should help you diagnose and fix the problem you are experiencing.
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