NASA Logo, National Aeronautics and Space Administration
NASA Space Science Data Coordinated Archive Header

Selected High-Resolution VLF Spectrograms on Microfilm


Availability: At NSSDC, Ready for Offline Distribution (or Staging if Digital)

Time span: 1965-03-21 to 1965-11-24


This data set consists of VLF spectrograms, produced by Rayspan equipment, on 16 100-ft reels of 35-mm microfilm, showing time of signal occurrence vs frequency of received VLF signals. Relative signal intensity can only be qualitatively judged by contrast between the background and the signal traces. These data are records of signals received by the 0.3- to 12.5-kHz broadband receiver and transmitted in real time when in range of a telemetry station. These data are of particular interest to the investigator and were selected from the low-resolution data (data set 64-054A-08A). These data are produced from the original telemetry tapes at higher film transport speeds than the low-resolution data. The horizontal (time) axis is stretched by at least a factor of 2 compared to the low-resolution data. This data set includes less than 0.2 of the low-resolution data. Since only time is noted on the sonograms, satellite position and other related information must be obtained from world maps (see data set 64-054A-00C).

Alternate Names

  • Sel Hi-Res VLF Spectrograms,Mfilm


  • Space Physics: Ionospheric Studies


  • 64-054A-08B

Additional Information



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



NameRoleOriginal AffiliationE-mail
[] NASA Logo -