Due to a history of difficulties and lack of patience with foreign idiots,
I'm looking into ditching my BT line (and 512 Kbps broadband) and using
mobile broadband for internet (and voip). The only useble signal where I
live is Vodafone and they seem a bit more expensive. There is a T-Mobile
signal in the vicinity, but not in the house. Would using an antenna and a
long cable to elevate it be worth trying?

If so what sort of antenna would I need?

Would I need a different sort of antenna to capture a "3" signal?

Would the cable be the same? (for T-Mobile and "3")