Sipowicz:
Apologies for getting your name wrong. I put it down to a lack of alcohol!
Potty64:
If your TV is currently displaying a signal from your Sky box you're effectively using it as a monitor. i.e. the signal from the Sky box is being fed into a socket at the back of the TV, which is then fed straight to the screen and speakers, bypassing the tuner section of the TV by using the 'AV' option. You need to revert to the 'TV' option. Looking at the remote control for your set
http://p.playserver1....1964893_500x500_1.jpg
shows that there's a button labeled 'TV', which should do exactly what you want. (If you've never tuned in the channels at all, you might need to do that now - press the 'Menu' button and look for the 'Auto Tuner Setup' option, assuming, of course, that you've got an aerial plugged into the TV!).
To switch back to taking a signal from the Sky box press 'AV'.
Chris