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VLF Receiver, Fixed-Frequency Signal Strength

NSSDCA ID: 1967-042A-05

Mission Name: Ariel 3
Principal Investigator:Prof. Thomas R. Kaiser


The purpose of this experiment was to make a worldwide survey of certain VLF signals and to study the effects of the propagation path on a 16-kHz, ground-based VLF transmitter. The experiment consisted of a fixed-frequency VLF receiver operating on frequencies of 3.2, 9.6, and 16 kHz. Bandwidths were 1 kHz on all frequencies with an additional narrow band (NB) of 0.1 kHz at 16 kHz. The observed parameters were minimum, mean, and maximum signal strengths at each frequency, except for the NB 16-kHz channel which observed minimum signal strength only. Time constants were 30 s for the mean values, 1 s for the NB minimum, 0.1 s for the other three minimum readings, and 0.01 s for the three maxima readings. Impulsive noise produced large variations in minimum, maximum, and mean readings in contrast to small variations for continuous signals. These signal strength observations were recorded each 28 s (about 2 deg) along the orbital path and read out on command each orbit. The experiment operated normally after launch and was operable until satellite reentry on December 14, 1970. For a more extensive description of this experiment see K. Bullough et al., "Sheffield University VLF experiment on the satellite Ariel 3," J. of Scientific Instruments, v. 1, pp. 77-85, 1968.

Alternate Names

  • Ariel3/VLFReceiver,Fixed-FrequencySignalStrength

Funding Agency

  • Unknown (United Kingdom)


  • Space Physics: Ionospheric Studies
  • Space Physics: Magnetospheric Studies

Additional Information

Questions and comments about this experiment can be directed to: Coordinated Request and User Support Office



NameRoleOriginal AffiliationE-mail
Dr. Arthur R. W. HughesOther InvestigatorUniversity of
Dr. Kenneth BulloughOther InvestigatorUniversity of Sheffield
Prof. Thomas R. KaiserPrincipal InvestigatorUniversity of Sheffield
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