The year of 1980

Field tests of ZOND-1 georadar, the first one of Zond GPR series. The equipment assembly was made using transistors and radio valves; it had considerable overall dimensions and weight and therefore was installed in a truck body. The flat antenna system was dragged by a rope on the ground surface. Sounding data were recorded as a density profile on a film and were also displayed as a trace on a CRT screen (please see next).

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