RESULTS OF RADIO-PROPAGATION EXPERIMENTS CONDUCTED DURING THE TOTAL SOLAR ECLIPSE OF 20 JULY 1963.
ARMY ELECTRONICS COMMAND FORT MONMOUTH N J INST FOR EXPLORATORY RESEARCH
Pagination or Media Count:
A series of radio-wave propagation experiments were conducted during the total solar eclipse of 20 July 1963 to measure its effect on the ionosphere. Receivers monitoring selected optimumly located standard radio broadcast stations and riometers indicating the level of cosmic noise were operated at Copper Center, Alaska, and Jefferson, Maine. A sweep-frequency receiver covering the entire standard broadcast band was also operated at the Maine site during the eclipse. Conclusive proof was obtained that the eclipse did affect propagation conditions at the frequencies utilized for standard broadcasting. Out of a total of eighteen broadcast stations monitored, located at intervals between 560 and 1570 kcs, the increase in the received signal strengths of seventeen stations ranged from 7.5 to 37 dB. All observed signal variations are asymmetrical with respect to the time of on-the-ground totality. There is a threshold phenomenon evident as the increases in signal strength occurred only when the majority of the suns radiation was cut off. The riometer operated in Alaska indicated a maximum increase of one-half dB in the level of cosmic noise at 30 Mcs. The change in cosmic-noise level occurred simultaneously with the beginning of the eclipse, increased to a maximum at ionospheric totality, and returned to normal at last contact. Author
- Celestial Mechanics
- Atmospheric Physics
- Radiofrequency Wave Propagation