@everetra - I think nowadays we take so many radio communications for granted. I remember when I was a kid, I got this electronic hobby kit which I used to build a crystal radio.
This required absolutely no power source; it used a crystal detector and long wire to pick up radio signals. The signals are not amplified so obviously the sound is very weak, but still it works.
I loved listening to my crystal radio when I was a kid. It opened my eyes up to the wonders of radio communications.