Home gaussmeter with filter-integrator circuit for measuring elf radiation

摘要

A meter (10) for measuring extremely-low-frequency radiation includes a coil circuit (22) whose output is filtered by a sharp-cut-off high-pass filter (24) to pass standard house-current frequencies but suppress the frequency components that would predominate as a result of movement of the meter with respect to the earth's magnetic field. An integrator (26) compensates for the frequency response of the coil circuit (22), an RMS circuit (35) converts the signal to its root-mean- square value, and a display circuit (28) provides a display determined by the resultant signal.