A new instrument has been developed and deployed for reception of broadband extremely low frequency (ELF) (defined in this paper as 300–3000 Hz) radio signals from sources related to seismic activity. The base is the designs used for decades at Abastumani Astrophysical Observatory and a concept representing the seismicity of Caucasus as a self-organizing criticality. We describe technical and application characteristics of instrument and test results in the locations for the first stations of planned network. Tbilisi State University Extremely Low Frequency Radiation Research Net (ELFTSU Net) is conceived as a base for scientific and educational activity of Electrical and Electronics Engineering students in practical analog and digital electronics, different sensor signal processing, data transmission, modeling of natural electromagnetic phenomena and corresponding observational system, organization of scientific data collection networks. The scientific problem requires dense, continuously developing network of stations. The ELFTSU Net student expedition has collected various data to further advance of project. The data reflect the dynamic range of phenomena from background diurnal-semidiurnal and wave phenomena in the Earth's crust. These data are compared with the level of urban electromagnetic background. It limits the possibility to observe the entire phenomena range, but allows observing processes related to strong earthquakes.