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The Conet Project: Recordings of Shortwave Numbers Stations is a four-CD set of recordings of numbers stations, mysterious shortwave radio stations of uncertain origin believed to be operated by government agencies to communicate with spies "in the field". The collection was released by England's Irdial-Discs record label in 1997, based on the work of numbers station enthusiast Akin Fernandez.

find out more at http://en.wikipedia.org/wiki/The_Conet_Project
also here:
http://irdial.hyperreal.org/

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Josh Spencer