Experimental apparatus for studies of the fine structure of low-frequency electromagnetic processes and some of its test results. I

A brief description is given of an experimental apparatus intended for studies of the fine structure of the spectra of wave packets excited in the circumterrestrial plasma and detected near the earth's surface or by satellites. The major component of this apparatus is an analog-to-digital data conversion system. The frequency range of this device is from 40 Hz to 15 kHz, its temporal resolution ranges from 250.10 to 16.10 microsec, and its frequency resolution is between 2 and 64 Hz in various regions of the spectrum of the investigated oscillation processes. Some test results are presented which were obtained using theoretical oscillation processes, laboratory sources, and natural wave packets.