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r a d i o q u a l i a would like to develop a project which is an aesthetic interpretation of electronic observation techniques. The project is named in reference to a contemporary method of electronic surveillance - Van Eck Eavesdropping. Van Eck TV will employ a method of contemporary surveillance outlined by Dutch scientist Wim van Eck. In paper published in 1985, entitled Electromagnetic Radiation from Video Display Units: An Eavesdropping Risk? Van Eck described how data can be collected from computer monitors, using the monitor's electromagnetic emissions. Van Eck pointed out that computer data was more vulnerable than people expected, making the observation that surveillers did not need access to a computer's hard drive in order to observe the data and activity of a computer. Surveillers could deduce the data on a particular computer by remotely monitoring the electromagnetic output of the display screen itself.
This surprising research unveiled and entirely new and covert method of electronic observation.

Van Eck eavesdropping works in the following way:

Monitors emit EM-Fields
Electronic devices emit electromagnetic fields (EM-fields) that are produced by the signals or movement of the data. Computer displays that use a cathode ray tube (CRT) are an example of an electrical device which emits EM-fields. The nature of the EM-fields are effected by the oscillations of the monitor, which are in turn effected by the data being displayed on the screen.

Digital data effects EM-Field
Each item of digital content displayed on a screen has its own electromagnetic 'signature'. If that 'signature' can be decoded, the content of the data can be deduced.

Decoding EM-Fields
The screen's magnetic field can be demodulated to recreate the original data, allowing an eavesdropper to read the contents of a computer from several hundred metres away.

Read more about how van Eck eavesdropping works

Van Eck Eavesdropping has been the subject of a great deal of interest in recent years, as the use of personal computers becomes increasingly ubiquitous. The US Government has identified the practice as part on a project group entitled, TEMPEST. During the 1950's, the US government became concerned that emanations from encryption devices could be captured and then reconstructed using EM field monitoring devices. If emanations were recorded, interpreted, and then played back on a similar device, it would be extremely easy to reveal the content of an encrypted message. Research showed it was possible to capture emanations from a distance, and as a response the TEMPEST programme was established. TEMPEST has developed a set of classified standards for limiting electric or electromagnetic radiation emanations from electronic equipment, and has provided advice on how to shield devices so that eavesdropping is not possible.

The fact that monitors are actually transmitters of information can be visually represented in a range of interesting ways. Van Eck TV will explore the ways in which the information emitted by monitored can be remotely sensed and displayed.

At the makrolab, r a d i o q u a l i a would like to begin some practical research into the methods associated with Van Eck eavesdropping, and the ways EM-fields can be visually displayed.

Initial Research references:
- Electromagnetic Radiation from Video Display Units: An Eavesdropping Risk? by Wim Van Eck
- What is TEMPEST by Bruce C. Gabrielson
- Soft Tempest: Hidden Data Transmission Using Electromagnetic Emanations by Ross Anderson and Markus Kuhn