by Adrian Petersen
During the radio era before World War 2, there was quite a movement here in the United States, and in other countries throughout the world also, to establish shortwave relay stations in an endeavor to give wider broadcast coverage. At the time, television was a concept and not a reality, and FM radio was still a distant dream. The mediumwave band was not overcrowded though the mediumwave signal generally gave only local coverage. However, shortwave transmissions could give wide area coverage within the country, and even international coverage on a much wider scale.
Many mediumwave stations in the United States established shortwave relay transmitters during the late 1920s and throughout the 1930s to carry their programming to distant listeners. In fact, it is estimated that there have been somewhere around one hundred shortwave stations on the air in the United States during the past eighty years, and probably more than half of these were active during the pre-war era.
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