 Government agencies and smaller companies producing MT instrumentation for internal use include Vega Geophysics, Ltd. in Russia and the Russian Academy of Sciences (SPbF IZMIRAN); and the National Space Research Institute of Ukraine.Geometrics, Inc. of San Jose, California USA produces a high-frequency, hybrid-source AMT system combining both natural fields and a high-frequency (1 to 70 kHz) transmitter, as well as a multi-channel distributed network CSAMT instrument.== References ==

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