"sort aerial" is a form of shorthand speak meaning pay attention to your TV aerial.
The ghost image may well be caused by a reflected signal so that the TV is presenting two images - a strong signal and a weaker signal reflected from a large object - the two signals are separated in time of arrival and two images are produced.
This can often happen if the aerial position suddenly changes - moved by strong winds perhaps.
You need to sort your aerial I think.
Peccavi, December 2009
