011 a- GER ccc) Project 6.1 + Accurate Location of Flectromagnetic Pulse Source F. A, Lewis QBICLIVE To utilise the electrommetic signal oricinating from nuclear— weapon detonations to determines ceoind rere of detonation, Seconi~ @rily to obtain the yield data that is avail: >le in the bomb pulse, FQQCEDURE Location of Grount Zero is mje by use of an inverse Loran principle. The exact time the ‘omt pulse is received at various Stations is recoried. The exmot time difference in receipt of the electromagnetic pulse between two stations will be used to determine ae typerbolic curve which runs through ground sero, The point of intersection of two or more curves Jetemmines vround serc, There are tvo systems. One 2f the systems is known as the long base line system and the other, the short buse line system. tee has two sets of stations, Each sys- The long base line haa one set of sta- tions located in the Hawaiian Ialands (Midway, Palmyra and Maul) with ayachronising antenna station at Haiku, Maut, ani the other set of Stations in the States (Harlingen, Temes; Blytreville, Arkansae; Kinross, Michigan end Rome, New York) with synchronising antenna station at Cape Pear, North Carolina, The short base lines have one set of stations located in the Hawaiian area (Kona, Haveil; Papa, Hawaii; and Red Fill, Maui) the other set in California (Pittsburg, Woodland, and Maryville), BEST AVAILABLE COPY [9 we --