Abstract
The design of an induction magnetometer with optimum air-core coil is presented. The desired cutoff frequency of the magnetometer determines that the size of the coil should be minimized with the shape of a Brooks coil. An op amp to be used in the electronics determines the diameter of the winding coil, and thus the characteristics of the magnetometer are defined. A battery-powered induction magnetometer was fabricated and demonstrated validity of the design. It had a cutoff frequency of 18 Hz, a linear transfer function of 30 mV/nT, and a noise floor level of 300 fT/√Hz in the frequency range from 50 to 150 Hz. These results were in good agreement with the design.
