Radio waves - explanation

[QABoy]

Why is it when I have my radio on at work that different channels need my aerial in a different position. I use a long piece of wire for an aerial and if I have Radio 1 on I hang it North to South over the back of my bench. When I have Radio 2 on I have to place it West To East.

Its one of those phenomenoms thats always intrigued me.

 

[Freefaller]

Buildings, weather, obstacles, and lots of other considerations can interfere with radio waves, some are defracted, some are bent, some are echoed and bounced so your aerial can be in the optimum position for one set of frequencies, but totally out for another which don't get bounced around as much, or get polarised in a different way owing to the environment and mediums they are travelling through.

 

[delta555]

Also depends upon where the signal is coming from. Since you are using a loop of wire, the induced current is stronger in different positions for different sources. Also, when freefaller has said is correct.

By the way, i am studying electronic engineering, so this stuff is what i do.