. The Bell System technical journal . 40 FREQUENCY IN KILOCYCLES PER SECOND Fig. 5—Attenuation of open-wire pairs, 165-miI copper, 8-inch spacing, CS insulators. z 12 ^ ^ 7 ^ / 1 DECIBELSPER MILE ^ /^ /^ X y / y / / f 20 40 50 60 70 80 90 100 110FREQUENCY IN KILOCYCLES PER SECOND 120 130 140 150 Fig. 6—Attenuation of 165-mil copper, 8-inch spaced pair of wires measured on a105-mJle section of the Amarillo-Albuquerque line in clear weather. 242 BELL SYSTEM TECHNICAL JOURNAL Pole Spacing and Insulators Poles must be spaced uniformly in order that the transpositions maybe most effective, and
. The Bell System technical journal . 40 FREQUENCY IN KILOCYCLES PER SECOND Fig. 5—Attenuation of open-wire pairs, 165-miI copper, 8-inch spacing, CS insulators. z 12 ^ ^ 7 ^ / 1 DECIBELSPER MILE ^ /^ /^ X y / y / / f 20 40 50 60 70 80 90 100 110FREQUENCY IN KILOCYCLES PER SECOND 120 130 140 150 Fig. 6—Attenuation of 165-mil copper, 8-inch spaced pair of wires measured on a105-mJle section of the Amarillo-Albuquerque line in clear weather. 242 BELL SYSTEM TECHNICAL JOURNAL Pole Spacing and Insulators Poles must be spaced uniformly in order that the transpositions maybe most effective, and an occasional deviation of only thirty-five feetis the maximum permitted. Where it is impossible to locate poleswithin this limit, such as is the case at long-span crossings, specialfixtures are suspended from steel cables at the proper points to permitmaking the transpositions. New types of insulators on steel pins, each pair of which is elec-trically bonded, are used to improve the stability of the 40 50 60 70 80 90 100 110FREQUENCY IN KILOCYCLES PER SECOND 120 130 140 150 Fig. 7—Far-end crosstalk between wires 7-8 and 9-10 of Amarillo-Albuquerque line,measured from pole 1 to pole 4236, a distance of 105 miles.
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
