I always say this when someone asks why I am interested in radio, when you can make phone calls for free from pretty much anywhere to anywhere else.

One day, all that infrastructure may be switched off, or just gone. But I’ll be able to take a piece of wire, hoist it into the air and have a two way conversation with people thousands of miles away.

It’s also just very interesting I think, the way the signals are propagated differently at different wavelengths at different times.