soney trintron kd28dx40u?

when I plug in airel at the back of tv and loop out the outher 2connections with a lead I go in2the menue to tune tv and nothing gets stored it tells me 2plug in the aerial. or is the aeral connted. I have tried everthing all I egt is when I put the topbox in I get sound comeing through the cam channel by messing about with it plse help me im getting fed with it