[BC] What brought me into radio

[novaelec@sbcglobal.net.INVALID]

Probably the greatest mystery in radio.  The real story of numbers stations has never been told, as there are still a few operating.  They are primarily believed to be related to espionage activities, but exactly what the message being conveyed is a source of great speculation.  Here is a good article on them, which covers most of the theories.
http://www.dxing.com/numbers.htm

The best espionage story I ever heard was how an AM station in Miami was used for covert communication many years ago.  It was a station that was heard regularly in Cuba, and rarely jammed as it was primarily a music station and carried little news or other information.  The CIA had installed a modification to the transmitter, with a secure phone line attached to the modification box. Nobody knew what it was, and the transmitter operated normally... as far as anyone knew (the Chief Engineer knew, but nobody else).

The "modification" was a trimmer across the main crystal, and would shift the carrier 2 Hz plus or minus.  This was a slow speed frequency shift keying "teletype" that ran for years and nobody had a clue.  It finally had its cover blown when a local ham tuned his receiver to listen to it, but still had it in CW mode, and heard the shifting carrier on the BFO.  Being a good steward of the airwaves, he called the station and told the Chief that his oscillator was unstable, as his carrier was shifting back and forth.

The next day the "mod" was removed, and has never been used again.

From: Ira Wilner <bdcst at vermontel.net>

What about the infamous numbers stations on SW?

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