Why does AM radio transmit over a longer distance than FM and why is AM disrupted easier than FM by things like underground carparks or tunnels?
In: 2
AM over mediumwave frequencies can curve around the Earth to a limited extent to reach over the horizon, it can also go around large structures. Longer wavelengths work better. At night the signal is trapped between the surface of the earth and the ionosphere and can be received across a continent if not encountering interference from other transmitters.
I can’t explain about carparks. My experience with FM is the opposite inside concrete buildings on the ground floor.
Latest Answers