Number Stations

A few weeks ago, Stuart (VA7QB) rediscovered 'Numbers Stations'.  Remember them?

Most would think that these clandestine transmissions faded after the Cold War and the fall of the Soviet Union.  Not so.

February 2nd, Stuart captured 'M12', A Russian SVR (successor to the KGB) coded message to someone in the Pacific Region.  Or so it is thought.  These stations, with the intended recipient often using one-time pad encryption, have persisted from the Cold War into the modern era.  Sweden, Poland, the UK also have known numbers stations, although officially they don't exist.

SVR-linked (Russian) stations (such as E07, M12, and XPA) are frequently active in the high-frequency spectrum.  In cataloguing these, the prefix 'E' means 'English', 'M' means Morse Code, and 'X' meaning... er, something.  I don't know!

For a listing of known broadcast times, which links to full, known descriptions, see: https://priyom.org/number-stations/station-schedule

Of all the online resources, PriYom is one of the more comprehensive, guaranteed to keep you busy.  It turns out that there are now RTTY numbers-stations, as well as a host of otherwise unknown modes.

WHAT DID I HEAR ON FEBRUARY 2ND?

I heard 'M12', an SVR morse code numbers station aimed at someone in the Pacific Region.  The first ten-minute session was on 15.937 MHz at 0320 UTC, to be repeated in full at 0340 on 14.537 MHz.  Purportedly an SVR service, presumably communicating with an agent(s) equipped with only ordinary, even lo-grade shortwave receiver, guaranteed not to attract attention. https://priyom.org/number-stations/morse/m12

These messages are copied, then paired with a 'one-time pad', a decidedly lo-tech decryption device.  It's just paper, simply a pad of paper, itself with the code needed to decipher the digits as they come through.  Once one page of the pad is used, it is ripped out and destroyed.

Please see the attached pics - the captured decode of the CW is from a Yaesu FTDX-10.  Included is an M4A sound file, which is 7 minutes of what hearing it was like.

A TYPICAL STRUCTURE FOR THE BROADCAST

M12 is a typical numbers station, although it had no introductory signature tune.  It started on 15.937 CW at 0320 UTC sharp, with a couple of 14 WPM repeated introductory messages - '495 495 495 495 1'.  Presumably the '495' is either the identity of the agent, or the page in the one-time pad to be used, then destroyed.  The '1' is probably the same as a page break.

Then the message itself is delivered at a rapid 24/25 WPM.  For me, that was a tough read.  'T' means zero, saving on the time CW takes to put out an actual 'zero'.  Then the whole thing ends with 'TTT', three zeros, repeated just in case it had been missed.

What did it mean?  Who knows.  It could have been the nuclear codes, it could have been a shopping list for supper.

Then the whole thing began again at 0340 UTC on 14.537 MHz.

CONCLUSION

Me, I felt like I did in 1982 with an old Realistic DX-302 receiver in Manitoba.  It's when I first said, 'what the hell is that?'  They were broadcasts way outside of either ham or shortwave-service bands.  Quite illegal.  Hearing them almost bankrupted me - next receiver was a Yaesu FRG-8800, pound for pound the best receiver I'd owned, especially with the work I'd put into a receiving antenna!  It was an eerily quiet folded-dipole, cut for 14 MHz.  I also listened for numbers stations on an Icom IC-R75.

Now?  There are some decent YouTube resources which can be found with a 'numbers station' search.  Don't blame me if you now get the bug and waste hour after hour chasing these unknowns.  Partially-knowns?

You're guaranteed to get paranoid, really paranoid.