The Swedish Rhapsody, by the numbers ...

I don't even remember what it was I was looking for exactly. Something to do with radio, following links here and there, when I ran across a strangely mysterious site called The Conet Project. The project consists of a 4-CD set of recordings of so-called Numbers Stations as heard on SW radios in the HF bands. The recordings have been put together by a fellow obsessed with these kinds of broadcasts for many years, Akin Fernandez. He hasn't discovered anything new, but he has been a catalyst for re-awakening awareness about these enigmatic transmissions that have been around nearly as long as radio itself. 

Here are a few samples I pulled off the archived CD set (freely available here, btw). 

Swedish Rhapsody
Dashes
Gong Chimes
DFD 21
Strich
Russian Man

English: Silhouette of a spy with a stolen document (Photo credit: Wikipedia)

I wonder if in my early days with radio as a SWL enthusiast if I ever heard such stations. I don't recall, but probably I would have given them little thought, probably have shrugged and turned the dial. It wouldn't have occurred to me to think of these as "spy transmissions" at all. That, anyway, is the unofficial, circumstantial, officially denied, consensus of many. The aficionados do make a convincing, but not air-tight case for their consensus. In the end, I think their explanation that these are coded messages sent to spy networks is just as good as any and certainly the most enticing!

Here are the highlights of their reasoning:

• You might think that transmitting unscrambled "plain text" secret messages over easily-accessible SW bands would be a genuinely foolish effort. It has advantages however. For one it's great for the spies as they only need a small consumer-grade SW receiver, one that is not likely to arouse suspicion. Possessing specialized radio or decoding equipment (like we hams have!) could draw attention from Nosy Parkers. 
• Following on that thought, the next piece of evidence is that most, if not all, such transmissions are coming from high-powered stations, in the range of 10-100 KW (up to 500 KW in one case). How is this surmised? Beyond me, though real experts with propagation conditions and some well-scattered spotters could figure this out I guess. If these are spy message broadcasts and the spies are using cheap receivers without large antennas, then the signals would have to be strong to compensate.
• Not too many folks can run stations at that power except governments, which is sort of a self-referential further argument that these are spy station broadcasts.
• Such transmission, first in Morse, later AM, and more and more in SSB, have been going on for a long time. During the Cold War their number peaked. They have dropped to about a third since the end of the Cold War. This certainly seems to lend some credibility to the spy theory, though I don't have to think too hard to conjure alternative reasons, such as the rise of the Internet and the ubiquity of cheap computers.
• I guess the most compelling evidence to me is the total denial of any government to come clean about what these transmissions are. But that is reasoning by omission, which doesn't have a great deal of logical weight.

One key question that can't, by it's nature, be answered definitively is, if these are codes why can't they be broken? Well, in some isolated cases they have been broken. And those cases give weight to the idea that the only sensible way to send such messages in the open, as it were, and still keep them secret is that they are using the technique of a "one-time pad" or one-time shared key. This technique of encoding is deceptively simple, usually amounting to adding (modulo) the letters of the key to the letters of the message one for one. It could be done with paper and pencil by any spy worth his salt (or her Salt). Yeah, bad pun... 

Anyway, a one-time pad has been around since the 19th Century and is considered unbreakable if the key for the message is used once and only once. It has some practical disadvantages, not the least of which is key distribution, but it's, again, plausible that these messages could be using the one-time pad technique. Though with laptops ubiquitous and cryptographic libraries easily downloaded, this conveniently tidy explanation is starting to get my skepticism into a lather. 

Whatever they are, they are interesting and amusing. It's one more way to extract a little fun from our rigs, wouldn't you say?  Maybe I'll tune around outside the ham bands sometimes and see if I can spot one of these Cold War relics.

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