This model has a built-in digital Freeview tuner, so to perform an auto tune you would need a standard aerial connected to the socket on the back of the TV first.
However, as you have Sky+ HD, you don't need to do that as the tuner you will be using is the Sky box which is connected to your satellite dish with two aerial leads. You then need to connect one end of an HDMI lead to the back of the Sky box and the other end to the 'HDMI 1' socket on the back of the TV. You change channel using the Sky+ HD remote control and not the Sony remote.
Hope this makes sense and answers your question adequately.
