[mike256]

But it still works almost the same way. You hold it near a thing to get energy is mostly required because it works with very little power, let's say some milliwatts. Whereas old AM stations where sending in the range of megawatts.

[c12]

That broadcast power is required to provide range. Radio waves obey the inverse-square law: for every doubling of the distance from source you get four times less power. This is also why wireless power transmission at a distance isn't really viable.