On March 22, 1956, preliminary satellite tracking tests began in a field near JPL. The antenna is being assembled in the photo above. The prototype Microlock ground receiving station included the antenna, instrumentation built into a 25-foot van, generators, and other equipment. Less than two years later, the Microlock receiving station helped tracked the successful orbit of Explorer 1. Photo number 331-2426A
NASA / JPL / B. Rowe
1956
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