Pirate radio

Pirate radio or a pirate radio station is a radio station that broadcasts without a valid license.

In some cases radio stations are considered legal where the signal is transmitted, but illegal where the signals are received—especially when the signals cross a national boundary. In other cases, a broadcast may be considered "pirate" due to the nature of its content, its transmission format (especially a failure to transmit a station identification according to regulations), or the transmit power (wattage) of the station, even if the transmission is not technically illegal (such as a web cast or an amateur radio transmission). Pirate radio is sometimes called bootleg radio (a term especially associated with two-way radio), secret radio (associated with heavily politically motivated operations) or free radio.

Radio "piracy" began with the advent of regulations of the public airwaves in the United States at the dawn of the age of radio. Initially, radio, or wireless as it was more commonly called, was an open field of hobbyists and early inventors and experimenters. The United States Navy began using radio for time signals and weather reports on the east coast of the United States in the 1890s. Before the advent of valve (vacuum tube) technology, early radio enthusiasts used noisy spark-gap transmitters, such as the first spark-gap modulation technology pioneered by the first real audio (rather than telegraph code) radio broadcaster, Charles D. Herrold, in San Jose, California, or the Ruhmkorff coil used by almost all early experimenters. The navy soon began complaining to a sympathetic press that amateurs were disrupting naval transmissions. The May 25, 1907, edition of Electrical World in an article called "Wireless and Lawless" reported authorities were unable to prevent an amateur from interfering with the operation of a government station at the Washington, D.C. Navy Yard using legal means.

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