DEVICE FOR GEOELECTRIC RECONNAISSANCE Russian patent published in 2000 - IPC

FIELD: frequency sounding using magnetic and electric excitation of electromagnetic field. SUBSTANCE: invention preferably may be used for phase-sensitive measurements for investigation of apparent resistance of upper Earth layer in wide frequency range. Device has field excitation source, first, second and third control lines, which are connected to control inputs of first and second frequency synthesizers and digital phase shifter, respectively. Digital phase shifter is inserted between output of second synthesizer and control input of phase-sensitive rectifier, which signal input is connected to field detector, and which output is connected to input of band-pass filter, which output is connected to signal input of phase-sensitive analog-to-digital converter, which is connected to input of indication unit. In addition device has power amplifier, which is connected to output of first frequency synthesizer, which is connected to output of first oscillator. In addition device has second oscillator, which is connected to input of second frequency synthesizer, first and second frequency dividers, commutator, which is inserted between field excitation source and power amplifier. First frequency divider is inserted between output of first frequency synthesizer and control input of commutator. Second frequency divider is inserted between output of second frequency synthesizer and control input of phase- sensitive analog-to-digital converter. First and second control lines are connected to control inputs of first and second frequency synthesizers, respectively. Setting input of second frequency divider is connected to setting input of second frequency synthesizer and fourth control line. EFFECT: increased precision for measuring real and imaginary constituents of electromagnetic field. 1 dwg