watching bt putting new cables in for broad band i thought why can we not use the satellite instead of old wires that are many years old
Well, if you have sky, the further north you live the bigger dish you need although in reality, Im not sure if sky now provide two sizes of dish.
Due to the weak signal sky transmit, poor weather such as snow or heavy rain can interupt tv reception. I used to have the BSB 'squarial' which was small compared to even today's sky digital dish. Reception was never interupted by heavy rain. Now, whenever we have heavy rain, the sky picture pixelates and sometimes we lose transmission altogether.
Fibre to the Cabinet (FTTC) is very good providing you're no more than a kilometer or so from your street cabinet. More than this and speed drops off considerably. If you have aluminium cable from the cabinet to home, you might find even if you live less than a kilometer, your speed can be less than 20Mbps.
Fibre to the premises \ home (on demand) (TTTP \ HoD) is fibre all the way from the exchange to your home and requires dedicated installation from the nearest enabled cabinet to your home. This is currently capable of delivering 330Mbps but is very expensive to install.