Minitrack and Sputnik
By October 1, 1957, Minitrack was complete except for the checkout of some teletype links and the calibration of some stations. Three days later, Sputnik i began crossing the Minitrack fence every 96 minutes; but it was transmitting at 20 and 40 MHz. Minitrack operators knew Sputnik I was passing overhead but could not track it with 108-MHz interferometers.
Sputnik I was transmitting in the amateur radio bands and getting good publicity as hams all over the world picked up the signals. Army radio engineers and many amateurs spent the night of October 4 building and modifying their equipment for Doppler tracking. Crude orbital data were available within a day. At NRL, the minitrack team had already begun to modify Minitrack for 40-MHz reception. Alerted by radio announcements of the Sputnik launching, they burned the midnight oil cutting 40-MHz dipoles and planning network modifications. 40-MHz crosses were quickly installed at Blossom Point, San Diego, and Lima; and, later, at Santiago and Woomera. In several days, good tracking data were being received. Sputnik 1 and Sputnik 2, in fact, gave Minitrack good shakedown runs.
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