Accession Number:

ADA045423

Title:

ELF Field Strength Measurements made in Connecticut during 1975.

Descriptive Note:

Technical rept.,

Corporate Author:

NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CONN NEW LONDON LAB

Report Date:

1977-08-15

Pagination or Media Count:

45.0

Abstract:

Both 42 and 76 Hz horizontal magnetic field strength measurements amplitude and relative phase were made in Connecticut during 1975. These measurements were for the purpose of further investigating sunrise, daytime, sunset, nighttime, and seasonal ELF propagation variations. The transmission source for these 1.6 Mm range measurements was the U.S. Navy ELF Wisconsin Test Facility WTF. The principal results obtained from these measurements were 1 ELF nighttime propagation is much more variable than daytime propagation, 2 the Halloween effect was observed for the sixth year in a row, 3 phase velocity changes during pure nighttime propagation conditions occasionally appear to be greater than changes associated with the sunrise-sunset terminators crossing the transmitter or receiver locations, and 4 there may be as many as 80 nights each year when the average nighttime field strength will be approximately 3 dB lower than that on preceding or following nights. Author

Subject Categories:

  • Test Facilities, Equipment and Methods
  • Electricity and Magnetism
  • Radiofrequency Wave Propagation
  • Radio Communications

Distribution Statement:

APPROVED FOR PUBLIC RELEASE