The Evolution of Shortwave Radio by James Careless

by James Careless

With the advent of radio in the 20th century, the shortwave band (1710–30,000 kHz) soon became a hotbed of long-distance radio broadcasting. Used primarily by state-run international broadcasters, plus ham radio operators and ship-to-shore radio communications, the shortwave band was prized due to its astoundingly broad reach.

Full story at :

http://www.radioworld.com/article/the-evolution-of-shortwave-radio/279335