Numbers Station

A numbers station (or number station) is a type of shortwave radio station characterized by their unusual broadcasts, which consist of spoken words, but mostly numbers, often created by artificially generated voices reading streams of numbers, words, letters, tunes or Morse code. They are transmitted in a wide variety of languages and the voices are usually female, although sometimes men's or children's voices are used.

In the 1950s, Time magazine reported that the numbers stations first appeared shortly after World War II and were using a format that had been used to send weather data during that war. It is widely assumed that the broadcasts are used to send covert messages to spies. This usage has not been officially acknowledged by any government that may operate a numbers station, and QSL responses have been received from numbers stations by shortwave listeners who sent reception reports to said stations, which is the expected behavior of a non-clandestine station.

The best known of the number stations is the "Lincolnshire Poacher" (supposedly run by the SIS).

In 2001, the United States tried the Cuban Five on the charge of spying for Cuba. That group had received and decoded messages that had been broadcast from Cuban numbers stations. Also in 2001, Ana Belen Montes, a senior US Defense Intelligence Agency analyst, was arrested and charged with espionage. The federal prosecutors alleged that Montes was able to communicate with the Cuban Intelligence Directorate through encoded messages, with instructions being received through "encrypted shortwave transmissions from Cuba". In 2006, Carlos Alvarez and his wife, Elsa, were arrested and charged with espionage. The U. S. District Court Florida stated that "defendants would receive assignments via shortwave radio transmissions".

In June 2009, the United States similarly charged Walter Kendall Myers with conspiracy to spy for Cuba and receiving and decoding messages broadcast from a numbers station operated by the Cuban Intelligence Directorate to further that conspiracy.

It has been reported that the United States uses numbers stations to communicate encoded information to persons in other countries. The State Department operated several stations, such as KKN50, that broadcast similar "numbers" messages.