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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Marta Zapparoli is an Italian experimental sound artist, radio artist, improviser, performer, and independent researcher based in Berlin. 
In the recent years her work mainly involves the intersection of the visible and the invisible aspects of physics- seeking to activate all the poetic and conceptual levels. She capture unique recordings of electromagnetic radiation coming from the outer space, Radio Nature (VLF) and electro-smog, radio wave communication coming form the technological world. The relation-connection-dialogue between nature and our technological world  is a central theme in her work. Her main instruments are a vary of antennas,radio receivers,detectors,tape recorders,band machine. She is active in live performances, site-specific, improvisation, site 2003. She is a member of Splitter Orchester in Berlin among other projects.

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.

In keeping with its 'Free Music Philosophy', the Irdial-Discs label has made the entire collection available for download in MP3 form (along with a PDF version of the included booklet) on its website completely free of charge and encourages fans to freely distribute it on file sharing networks.

More on http://en.wikipedia.org/wiki/The_Conet_Project