I'm in south west Cornwall - just about as far off the Thor footprint as you can get in mainland UK. With a 90 cm dish, I can get all the Kiosk channels, Discovery, MUTV etc during the daytime and if there's no cloud. As soon as night falls or we get heavy cloud cover, reception goes to pot. My 1.1 metre Triax dish arrived today, so I've spent most of the afternoon fiddling with the mount to get the arc as near perfect as possible. Unfortunately, this wasn't helped by bearing failure on my old motor (that's another story) but preliminary readings show that signal strength and quality on 1 deg W are almost 100% better with the bigger dish - even after the sun sets. My guess is that in Chelmsford a 1.1 metre dish would give good reception and you might even pull in TV1000 on Sirius - provided that your arc tracking is accurate.