Defense News
04/26/2010
Chinese Spy Radio?
‘Thank You for Listening’ Says Mysterious ‘Numbers Station’
By WENDELL MINNICK
TAIPEI — Debate over the origin of a shortwave radio broadcast in Chinese reciting numbers remains unresolved as Taiwan military and intelligence officials deny responsibility, while others suggest China is behind a “numbers station.” Described as one-way voice links, “numbers stations” have been used since World War I to send encrypted messages to spies.
On Feb. 1 at 11.430 MHz, a broadcast of a female voice recited 20 sets of four numbers in Chinese: “Now we’re ready to broadcast the first 55word telegram of February. Unit 2236 please write down and receive. 2744, 3449, 1269, 2291, 1773, 7330, 9816, 8023, 1872, 7381, 9726, 5171, 2227, 5393, 6736, 3842, 7994, 7732, 3102, 4911. This is the 20th set telegram that was just broadcast.”
During a broadcast April 20 at 10.520 MHz, with what some called a Taiwanese accent, a female voice signed off in Chinese with: “Thank you for listening. Wishing you good health and a happy goodbye.”
The broadcasts do not use any standard broadcasting protocol, such as identifying the station or origin.
A Taiwan government communications official said the broadcasts are a “topic not open to discussion or inquiry.”
Officially, Taiwan’s Ministry of National Defense (MND), upon listening to the messages, said, “no comment.” However, an MND official said the broadcasts were coming out of China, not Taiwan, and the military was aware of them.
Though the method appears antiquated, there is a beauty to using the system.
“There’s no link to the recipient. With e-mail and other methods, there’s always the chance of identifying the recipient. Also, all that is required is a common portable shortwave radio,” said Chris Smolinski, who moderates the Spooks Digest Listserv via the Black Cat Systems Web site. Spooks Digest routinely identifies numbers stations around the world.
Numbers stations reached their peak during the Cold War, only to decline significantly after the Berlin Wall fell in 1989, though China, Cuba, Israel and North Korea have been accused of continuing to use the method.
Some sources have suggested the broadcasts are a “false flag” operation to confuse the enemy.
“Some percentage of the transmissions from such stations are very likely to be dummy traffic to make it harder for counterespionage outfits to draw conclusions about the number of spies working against them and their level of activity,” said a U.S. defense analyst, adding that such agencies would quickly figure it out if it were all dummy traffic.
“It only makes sense to operate such a station if you are communicating with real spies.” However, not everyone agrees the broadcasts are intelligence-related.
“It is easy to be conspiratorial about numbers stations, and there is no doubt that they have been, and still are, used in intelligence and military operations,” said Gary Rawnsley, professor of Asian international communications at the University of Leeds.
“However, they are also used for technical reasons to check the clarity of signals, etc., on specified frequencies. Sounds boring, but there we go.”
Other sources said the broadcasts could be connected to the Chinese Telegraph Code (CTC) to communicate with fishing vessels, said Scott Henderson, author of the book “The Dark Visitor: Inside the World of the Chinese Hacker.”
“The CTC runs from 0000-9999 with the character for each block identified by an individual number,” he said. “If the operator passes the string 1034, 6878, 9801 ... etc, just write out the characters and see if they form a sentence. If they don’t, it’s coded.”
However, the numbers do not match the CTC.
“I can guarantee this is not for fishing boats or any other commercial radio communication,” said a Taiwan defense analyst.
Erik Baark, author of “Lightening Wires,” a history book on the CTC, said the broadcasts sound like someone using the CTC, but “to my knowledge, one would not use this method in communication with commercial fishing. … Either one would use Morse code, easier to distinguish on shortwave, or one could simply read the text.”
Smolinski said the signal strengths of the Chinese broadcasts “are a bit too high for it to be someone using a ham transmitter,” or amateur radio. There are also too many transmissions.
“The hoaxes in the past have generally been one-time affairs, and obvious pranks, done for entertainment, with no attempt to pass them off as ‘real’ numbers transmissions,” he said.
Members of the local Chinese Taipei Amateur Radio League dismissed suggestions the broadcasts are fake. “We don’t know who is broadcasting the numbers,” said one member. “It could be China or Taiwan.”
Those who doubt countries continue to use the method need only look at Cuba. In 1998, the U.S. government arrested a group of Cuban intelligence agents, known as the Wasp Network, receiving instructions from a Cuban numbers station being operated as Atención.
In 2001, a U.S. Defense Intelligence Agency analyst, Ana Belen Montes, was arrested for spying for Cuba. Investigators discovered she also received instructions from Atencion.
However, some sources are still debating why China or Taiwan would continue using a system that seems antiquated in comparison to the Internet and cell phones.
“It seems like an arcane practice, but espionage tradecraft also loves the tried and true,” said Richard Bitzinger, a former U.S. intelligence analyst. “Agents still use dead drops, microdots, etc. Shortwave radios are easy to come by and operate, and when all the really sophisticated means of communication fail, this is probably a good fallback.”
