I have started using a Dongle on my PC as I was having so much trouble with broadband connection via telephone line.
My Q is once the signal has been disconnected do I need to unplug the dongle from my usb or can I leave it till I connect next time.
You can leave it plugged in but be very sure that you have not got it set to auto connect on demand in any way, otherwise you will find it connecting randomly and potentially running you a large bill up (or just using all your credit up)