Report on the Soviet Earth Satellite
February 1958 Radio & TV News

February 1958 Radio & TV News

[Table of Contents] Wax nostalgic about and learn from the history of early electronics. See articles from Radio & Television News, published 1919-1959. All copyrights hereby acknowledged.

Interestingly, the February 1958 article in Radio & TV News magazine titled "Report on the Soviet Earth Satellite" never mentions the craft's name - "Sputnik 1," or "Простейший Спутник-1," which in English is "Elementary Satellite 1." Sputnik 1 was, in case your history is a bit fuzzy, the world's first successful artificial communications satellite. Launched by the Union of Soviet Socialist Republics (USSR) on October 4, 1957, Sputnik 1 remained operational for about three weeks in low Earth orbit (284 miles average), during which time radio receiving stations across the globe anxious tuned in hoping to hear the 20.005 MHz and 40.002 MHz pulses that alternately repeated continuously in an alternating manner - the first FSK (frequency-shift keying) from space. Russkie engineers made the signal frequencies and periods as stable as possible in order to enable careful frequency and timing, combined with time and locations of contact reports to serve indirectly as telemetry data which once assimilated would provide orbital track, altitude, speed (Doppler shift), atmospheric absorption and refraction effects, and other scientifically valuable information. Amateur radio operators were encouraged to forward contact reports to Moscow, and were rewarded with special QSL cards (which now sell for a good price on eBay).

Report on the Soviet Earth Satellite

Example of orbit prediction of USSR satellite prepared by U.S. Naval Research Laboratory. Times computed for latitude 40°N; released October 15, 1957, 11:30 a.m.

Summary of radio observations and instrumentation employed in man's first artificial earth satellite.

The material below is based on a composite of unofficial reports on the first USSR satellite which was launched on October 4, 1957. The information was taken from the "IGY Bulletin", a survey by the U. S. National Committee for the International Geophysical Year.

Instrumentation

The first announcement by Radio Moscow indicated that there were two transmitters in the satellite, one operating at 20.005 mc. and the other at 40.002 mc. The pulse of each signal was 0.3 sec., followed by a pause of similar length during which the other signal was transmitted. On Oct. 8 the signals were not received for several hours. Later, signals resumed but became continuous. The transmitter power was specified to be 1 watt. U. S. monitors agreed that the signals were modulated with telemetry data. Appropriate instruments within the satellite reported on atmospheric temperature and density. Also, information on micrometeorite bombardment was probably transmitted.

Radio Observations

First U. S. radio reception of the satellite's signals was reported by RCA Communications, Inc. at Riverhead, L. I. The observation occurred at 8:07 p.m. EDT, October 4, the day of the launching. At 8:15, the signal was strongest from the south. First reception at the Naval Research Laboratory in Washington, D. C., was at 8:30 p.m. By October 6, six of ten Minitrack stations had been converted from 108 mc. - the frequency to be used by the U. S . satellites - to 20 and 40 mc., in order to track the USSR satellite.

Radio reception was soon general and reports of continuous monitoring were received from Antarctic IGY stations, including the South Pole - which is in a position to hear the satellite on virtually every passage - as well as from IGY Drifting Station A, an ice floe located about 500 miles from the North Pole.

Reports from the Amundsen-Scott South Pole Station indicated that the satellite's radio signals cut in abruptly but faded out gradually and that there were numerous variations in signal strength, duration, and pulse rate.

The USSR was reported to be encouraging amateur assistance, offering special cards to hams reporting receipt of the satellite's radio signals. Radio Moscow announced on October 26 that the satellite's radio had used up its power and had stopped working. On the same day, the Naval Research Laboratory reported that no signals had been received by Minitrack stations since 5:50 p.m. EDT, October 25, and that no other information had been relayed to NRL from other radio receiver sources since 7:10 p.m, EDT, October 25. Thus, after 3 weeks of continuous operation, space's first radio transmitter had gone dead.