Hi,
Thank you for your reply,
If you are simply looking to connect a coaxial cable up to your board, then I would recommend buying a TV Tuner and using it's output to connect to the board.
The projector or board does not have a built in tuner, which you require if you connecting a Coaxial cable from the antenna.
To then connect the TV tuner to the board you simply use the Red, Yellow and white cables to the white wallbox in the picture.
You can also buy a TV Tuner for your PC which plugs in via USB and you can watch TV without switching source.
Hope this helps
Regards
Haymo