originally published June 28, 2013

My neighbor – not the ethically-starved bag of rancid douche against whom I was once plotting; this is the guy beside him – has a gigantic antenna on his roof. The thing has been there since we moved in back in ought-six, and I have no idea what he does with it. He might use it for ham radio, maybe for shortwave radio, or perhaps he forces lemurs to race to the top late at night, long after I’m asleep.
I suppose – and this is a long-shot here – he could be a spy.
Imagine you woke up this morning and took a walk to your local Radio Shack, searching for a piece of antiquated technology which you could adopt as a hobby. Perhaps you picked up a shortwave radio. Then, because you’re interested in meeting new people around the world but a little put off by the excessive quantity (and quality!) of penises you met on Chatroulette, you begin to fiddle with the band until you come across a voice in the darkness. A new friend perhaps?
No, this person is simply reciting numbers, and she wants nothing to do with you.
You have just stumbled upon a numbers station, one of the great mysteries of the radio world. Sometimes the voice is uttering letters, other times you might hear snippets of music or perhaps Morse Code. But it’s the numbers – those disembodied faceless recordings, dispassionately dropping digits like discarded wads of bubblegum… those are the real curiosity.
These stations started showing up amid the uncluttered airwaves shortly after World War I, making them among the first radio broadcasts in the world. So what are they for? My first guess was espionage, as a way to transmit data to embedded spies, who would then decode the numbers and destroy the evidence, all whilst blowing up a building and bedding three women. For a refreshing change, the most interesting and bad-ass explanation is, in this case, probably the right one.
No government has, in the history of ever, acknowledged that they have set up or run a numbers station. And really, why should they? If it’s there for covert spy purposes, I’d expect them to keep it secret. All a spy would need is a portable shortwave radio and a one-time pad. A one-time pad, or OTP as we call it in the espionage business (whoops! I meant ‘they’ call it that) is a simple cipher. You have a group of letters that signify other letters, and you use the code once before throwing it away. Or, if you’re a real professional, you eat it. Spies have to eat a lot of paper – that’s why they tend to have great gastro-intestinal coverage in their medical plan.
The theory here is that spies will listen to the proper broadcast from the numbers station, use their OTP to decode the message, then dispose of the key, rendering the code virtually unbreakable. The next broadcast would use a different cipher key. It’s really quite brilliant. And the fact that numbers stations can still be found in the shortwave spectrum suggests that it’s also quite effective.
The closest thing to an official admission of radio-facilitated espionage came from the British Department of Trade and Industry in a 1998 Daily Telegraph article, in which an official claimed the numbers stations “are what you suppose they are. People shouldn’t be mystified by them. They are not for, shall we say, public consumption.” At which point the official sipped his tea, twirled his mustache absent-mindedly, and chuckled to himself.
Well yes, Mr. Unnamed Official, we shall say that. Throw a little Jay-Z-inspired beat behind it and maybe dress it up with some autotune and then the public might show a little interest. Here’s a little sample of a bland, non-funktified numbers station if you’re curious.
That’s a sampling from the Lincolnshire Poacher numbers station, which broadcast throughout the Cold War, up until the summer of 2008. The opening beeps of jaunty music were used as an interval signal, designed to indicate that the juicy stuff was commencing. The song is “The Lincolnshire Poacher”, an English folk song that dates back to the 18th century, and its regular appearance on the station is what earned the station its nickname.
Amateur radio enthusiasts have traced the origin of the station’s broadcast to the RAF Akrotiri Air Force Base on Cyprus. It’s believed that MI6, the British Secret Intelligence Service, likely ran the station. Another broadcast coming out of Australia uses the similarly dated folk song “Cherry Ripe” as their theme. In late 2009, that station also went off the air.
No one knows why a numbers station might disappear. We certainly don’t live in an era in which spying is obsolete, nor is there anything quite as effectively transmitted and unblockable as a shortwave radio signal. It could be that MI6 switched to a new frequency and adopted a new identifier. I suppose we won’t really know until long after the fact.
The first numbers station to get called out and accused of espionage activity was the ¡Attención! station, broadcasting out of Cuba. In 1998, FBI agents entered a suspected spy’s apartment and copied the decryption program for the code that was being broadcast on the station, which used the word “¡Attención!” to act as its interval signal. A little less subtle than a song clip, but it did the job.
The United States used the decryption program to decode a handful of messages, which were then used as a major piece of evidence in the trial of the Cuban Five, a quintet of Cuban intelligence officers operating out of Miami. This marks the only time a numbers station’s true identity and purpose was revealed.
Jamming these stations can be difficult, particularly for the ones that don’t broadcast regularly, or those that broadcast on multiple frequencies simultaneously. In many cases, it’s suspected that a gentleman’s agreement exists between non-warring nations to simply leave one another’s spy frequencies alone.
I’d like to imagine my neighbor spends untold hours in his basement, listening via that massive antenna to endless streams of numbers, logging each broadcast in a tattered journal, with one of those huge walls of photos and scrap notes, linked to one another with red string. It took him a year and a half to build a deck in his backyard – the guy has to be busy doing something.
Not that I’m spying, of course…