Cuba’s Mysterious ‘Numbers Station’ Is Still on the Air
Written by Joshua Kopstein / September 16, 2015
Or at least, that’s the most common explanation for what I heard.
I dialed to the correct frequency—17480 kHz—using an internet-connected radio tuner maintained by a university in the Netherlands. Suddenly, over waves of static, an eerily-robotic woman’s voice began speaking a series of five-digit number sequences in Spanish.
About three minutes later, the numbers repeated in the same order, but this time each sequence was followed by a digital bell-like tone and a harsh blast of noise, like a 56K modem trying to connect to AOL in the 90s. This continued for about 20 minutes, each sequence punctuated by the bizarre noise blasts.
This is HM01, sometimes called “Voce De La Chica,” a shortwave numbers station believed to be operated by the Cuban intelligence directorate, Dirección de Inteligencia (DI).
To the casual listener, numbers stations are mysterious broadcasts of voices speaking streams of numbers which, in at least some cases, are encrypted messages being sent to government spies.
They have long seemed like Cold War relics, born in a time when spying meant boots-on-the-ground and internet surveillance was impractical or irrelevant. And yet, HM01 continues to operate in what the NSA has called a “golden age” of internet-enabled signals intelligence, and despite historic progress in US-Cuba relations earlier this summer.