Author: Tom Hagen
Title: Portable VLF Receiver for Making Calibrated Magnetic Field Strength Measurements
Abstract: This presentation is about the author's continuing efforts to get calibrated measurements of the field strengths of the various VLF stations used by the SuperSID program as reference sources to detect sudden ionospheric disturbances (SID’s). Presently, the amplitude of data coming in from the various SuperSID stations around the world is uncalibrated. When a SID is detected, there is a measurable change in relative signal strength, but actual field strengths are unknown. If a portable VLF receiver and loop antenna setup could be developed that is calibrated, then such a setup could be shipped to different sites for calibrated field strength measurements. Users could even build their own receiver and loop antenna from standard plans. A small loop design and two receiver designs are discussed. Estimated sensitivities of each receiver design are calculated. Calculations are verified with laboratory tests.