Shortwave radio operates between the frequencies of 3 MHz and 30 MHz. (The broadcast band of FM is 87.8 to 108.0 MHz in the US.) Amateur radio enthusiasts…
Shortwave radio operates between the frequencies of 3 MHz and 30 MHz. (The broadcast band of FM is 87.8 to 108.0 MHz in the US.) Amateur radio enthusiasts discovered the ability to communicate long distances using the shortwave band in the early 20th century, and since then it has been frequently used for international broadcasts.
Since the signals are refracted by the Earth's ionosphere, shortwave frequencies are capable of reaching any location in the world, although factors such as time of day and season can effect reception.
There are 14 short wave bands (some with limited or no use), and within each of those bands there can be hundreds of broadcasters. The practice of searching for and identifying stations in other countries is known to hobbyists as DXing, and many listeners also tune into utility broadcasts of maritime or military signals. International programs including BBC World News and Radio Australia also broadcast on shortwave bands.
