Aerial lead to 'Ant in' on YouView box.
Patch lead from 'RF Out' on YouView box to TV 'Ant in'.
Brill picture through HDMI cable from YV box to TV
No signal on the telly from aerial. Swapped a few leads, scratched my head and other body parts for a bit, then had a brain wave.
Went to the settings on the YV box, RF loop was turned off
That's one brain wave I haven't got a clue where it came from

I've never known it before, so what made me look?
More to the point, how much cash will the TalkTalk help phoneline raise with people asking 'I can't get a signal' !!