The shortwave radio signals that the alleged Russian spies were using are still surprisingly effective.

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July 6 2010 1:53 PM

7887 kHz, Your Home for Classic Cuban Espionage Radio

The shortwave radio signals that the alleged Russian spies were using are still surprisingly effective.

Antenna. Click image to expand.

The FBI documents that accompanied last week's arrest of 10 alleged Russian spies are alternately creepy—who knew the Tribeca Barnes & Noble was a hotbed of espionage?—and comical—turns out even foreign spies wanted to cash in on suburban New Jersey's real estate boom. With a nod to Boris and Natasha, the accused are also said to have used short-wave radio, a 1920s-era technology that, because of its particular place in the spectrum, can bounce off the atmosphere and travel across continents. The FBI's criminal complaint paints a picture of stateside spies hunkered down in front of their radios, year after year, in homes in Montclair, N.J.; Yonkers, N.Y.; Boston; and Seattle, furiously filling spiral notebooks with "apparently random columns of numbers" broadcast from the motherland.

Just as in the case of Cuban spies Walter and Gwendolyn Myers, arrested last summer in Washington, D.C., the clandestine Russian agents were tuning in to foreign short-wave stations transmitting strings of numbers—some in Morse code, others spoken by a recorded voice—that they then decoded into words. The so-called "numbers stations" carried regular broadcasts that could be heard by virtually anyone across the United States spinning their own short-wave dial past the BBC World Service or Radio France International, two of many neighbors in the shortwave spectrum.

It may seem like the digital era of spy technology has passed the Russians by. In the Washington Post, columnist Jeff Stein tittered that "the FBI must have been clapping its collective hands when it discovered the primitive radio techniques the Russians were using." But they aren't the only ones using short-wave radio for espionage. Great Britain has publicly admitted that its foreign intelligence agency, MI6, still uses "numbers" stations. And scientists have tracked numbers broadcasts to transmitters at government sites in Israel and (until they went silent in the late '90s) the United States. Here are two examples of what they sound like, from the Conet Project:

Recorded in July 1994 and believed to be an MI6 station.

Recorded in December 1991 and believed to be a KGB station.

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The reason this dusty method is still ideal for espionage is that, even if you locate a spy station's transmitter, you have no idea who's tuning in across the hemisphere. Unlike telephone or Internet connections, receiving a radio signal leaves no fingerprint, no traceable phone connection, no IP address, and no other hint as to where the recipient might be. The omnipresence of these "numbers stations" has engendered a community of eavesdroppers who pinpoint the stations and even take their own stab at unraveling the messages—guys like 43-year-old Baltimore-area computer engineer Chris Smolinski. When he is not running his appropriately named Black Cat Systems software firm, he's managing the Spooks list, an online gathering of several hundred amateur spy-radio buffs from around the world, all carefully scanning the short-wave bands and logging the daily bursts of numbers that fill the ether.

Smolinski has a fairly elaborate roomful of gear, complete with a humongous outdoor antenna that one can imagine has inspired suspicious neighbors to call the FBI about him. But you hardly need such an expensive set-up to channel your inner James Bond. "A little $49 handheld short-wave unit can pick up any of the Cuban stations," he says. Just tune in to 7887 kHz at the scheduled time and, clear as a bell, after an introductory "Atención!"you'll hear a female voice reading off sets of numbers. [Example below.]

Recorded in February 1995 on one of several stations confirmed by the FBI to be used by Cuban spies operating in the U.S.

With the precise numbers-to-letters code known only to a spy and his boss—and with the code intended to shift with each new broadcast—the encrypted messages are theoretically almost unbreakable. Unless, as in the famed 1946 "Venona" case proving Stalin's infiltration of the U.S. atomic bomb project, an agent clumsily reuses a "one-time" code. Or, if the FBI surreptitiously enters the spies' homes and copies their decryption keys, as occurred during this latest case of Russian espionage and prior to the 1998 Miami arrest of Cuba's "Wasp Network."

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