Googled this and this on digital spy came back
http://forum.digitalspy.co.uk/board/...d.php?t=119698
Indicates the combined digital radio bandwidth is 8Mb/s
An average DTV channel is 4Mbs
A quality one is already 8Mb/s
And an Analogue on is 36Mb/s
There are 40 odd analogue channels transmitted, switching off the analogue broadcast will free up 1440Mb/s of bandwidth that could be used for HDTV. I'm sure Proppin will come along and correct my guesstimates, but it looks like NTL will be able to carry the signals. You just need a new STB to decode them.