there is a menu button on the RCA which when pressed shows sleep,alarm,clock,auto program,edit channels antenna:air and list features.
That is your problem. Select "antenna:air" and it should toggle over to "cable" and then to "video", on some sets labeled "RYW" or "RCA inputs". Set it to that, and it will work just fine.
To flesh out what the deal is, there are multiple ways to get a signal from a DirecTV box (or any box) to the TV. The old fashioned way is coax cable. That is a "hub" which is a threaded thing like a screw. The cable has a connector that is threaded and screws on to the hub. Then there is what is called an "RCA input" (RCA invented it 1000 years ago, its just a name, found on everybody's boxes) that consists of three much smaller wires that have push in connectors of that are color coded red, yellow and white. There are then more advanced ones past that that, trust me, you don't have. The TV has a setting to toggle between these forms of inputs. Your TV is set to look to the coax hub (which is how you must hook up an old-fashioned antenna, and thus why it is labeled as such) and your box is wired into the TV with the RCA connectors.
You need to either set the TV to the correct input setting, or just get a piece of coax cable ($2 at Wal-Mart) and hook up your box that way.