VLF transmitting antennas multiple-tuning vs single-tuning

Reports on a detailed study of multiple-tuned VLF antennas by experimental and numerical modelling. The experimental model was placed on a 30 metre diameter elevated ground plane, so that the instruments to measure impedance and the effective height of an antenna under test could be deployed from beneath the wire grid ground plane. To measure impedance either a Hewlett-Packard RF impedance analyzer Model 8505A or a Model 4194A were employed. The numerical modelling studies used the numerical electromagnetic codes NEC-3 and MININEC-3. The MININEC computer program uses an IBM compatible microcomputer.<
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