In the early days of espionage, long before the advent of burner phones, satcoms, and other modern-day spy gadgets, getting word to field agents—especially those working behind the Iron Curtain—proved a dangerous game with global consequences should the agent's cover be blown. But that's where number stations, and their uncrackable radio codes, come in. A number station is one of many short-wave radio stations broadcasting a seemingly endless series of encoded messages throughout the world. To the untrained observer, these broadcasts sound like gibberish. They're typically recordings of a synthesized female voice (they're almost never real humans) reading strings of alphanumeric characters, often in a variety of languages including Spanish, German, English, Russian, and Chinese—or just straight morse code. These stations first came to the public's attention in the 1960s, when a Time magazine article revealed that they had been in use since the end of WWII, however additional research by The Conet Project suggests that they might have been put in place as far back as WWI. Nobody's really sure when these systems first came online. In fact, no government in the world has ever even confirmed that these stations exist, much less what they're used for. The leading theory behind their use—albeit one just as speculative as any other—is that these stations are transmitting encoded messages to covert intelligence agents working in hostile territories. It's not like you can just dial up a "cultural attache" working Pyongyang and ask how the spy works is going. The number station system is, when used correctly, is virtually impossible to detect and essentially foolproof. All the agent requires is a commercially-available shortwave radio and a one-time pad to decipher the message. So long as they're not under electronic surveillance or have the one-time pad discovered, there's effectively zero chance of having the message intercepted and decrypted. More via Gizmodo.
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