International Broadcasting - Restricting Reception

Restricting Reception

In many cases, governments do not want their citizens listening to international broadcasters. In Nazi Germany, a major propaganda campaign, backed by law and prison sentences, attempted to discourage Germans from listening to such stations. The practice was made illegal in 1939. In addition, the German government sold a cheap, 76-Reichsmark "People's Receiver", as well as an even cheaper 35-Reichsmark receiver, that could not pick up distant signals well.

The idea was copied by Stalin's Soviet Union, which had a nearly identical copy manufactured in the Tesla factory in Czechoslovakia. In North Korea, all receivers are sold with fixed frequencies, tuned to local stations.

The most common method of preventing reception is jamming, or broadcasting a signal on the same frequencies as the international broadcaster. Germany jammed the BBC European service during the Second World War. Russian and Eastern European jammers were aimed against Radio Free Europe, other Western broadcasters, and against Chinese broadcasters during the nadir of Sino-Soviet relations. In 2002, the Cuban government jammed the Voice of America's Radio Martí program and the Chinese government jammed Radio Free Asia, Voice of America, Radio Taiwan International as well broadcasts made by adherents of Falun Gong, .

North Korea restricts most people to a single fixed frequency mediumwave receiver; those who met political requirements and whose work absolutely required familiarity with events abroad were allowed shortwave receivers. Another method of reaching people with government radio programming, but not foreign programming, is the use of radio broadcasting by direct broadcasting to loudspeakers. David Jackson, director of the Voice of America, noted "The North Korean government doesn't jam us, but they try to keep people from listening through intimidation or worse. But people figure out ways to listen despite the odds. They're very resourceful."

Yet another method of preventing reception involves moving a domestic station to the frequency used by the international broadcaster. During the Batista government of Cuba, and during the Castro years, Cuban medium-wave stations broadcast on the frequencies of popular South Florida stations. In October 2002, Iraq changed frequencies of two stations to block the Voice of America's Radio Sawa program.

Jamming can be defeated by using very efficient transmitting antennas, carefully choosing the transmitted frequency, changing transmitted frequency often, using Single Sideband, and properly aiming the receiving antenna.

For a list of international broadcasters, see List of international broadcasters.