Hi Mac,
From the type number I can tell this is a CRT TV. The /05 indicates it is a UK version.
The problem you are describing sounds like a focus issue.
A word of caution first: unless you are a qualified electrician or have a solid electronics background, you should not attempt to fix or tune TV electronics.
The focus adjustment is found on the LOTP (line output transformer): the focus adjustment most commonly is a recessed screw on the LOTP (marked as "focus"). The LOTP can be accessed by opening up the back cover of your TV. Just google LOTP in case you want to know what it looks like.
LOTPs sometimes also have a "screen" adjustment: do not adjust this, as it will alter the brightness of your screen, which is not going to fix your problem.
Read my word of caution once more before you decide to start. The voltages inside a TV are potentially lethal.
Good luck.
SJ, March 2009