Theory and Practice of the Use of Power Transmission Lines for the Deep Electromagnetic Sounding of the Earth’s Crust

Most often, long grounded lines are used as sources of an electromagnetic field in deep sounding. An overhead power transmission line may be used for this. But the inductive reactance of the line limits the current in the line. The matching unit is designed to compensate this reactance. The results of development and construction of matching unit for stationary extremely low frequency transmitter for overhead transmission line used as antenna are presented. Aspects of electronic circuit design and selection of electronic components are given.