Tokyo and Kobe toll cable

The telephone cable between Tokyo and Kobe was opened for traffic on November 1, 1928. Previously toll circuits in Japan have mostly consisted of bare aerial lines. Since these are subject to storm troubles and involve short lengths of cable, the quality of conversation over them was poor. The total length of the cable is 333 km., and 184 pairs are provided: 54 pairs of 1.3-mm. wire for two-wire circuits, and 130 pairs of 0.9-mm. wires for four-wire operation. The cable is quadded, paper insulated and lead covered. Each loading point (1830 m. apart) is provided with one case for loading coils for 27 quads (two-wire operation), one for 35 quads (four-wire operation), and one case for 30 quads (21 four-wire and 9 two-wire). The coils are designed to give 177 and 107 m.h. for side and phantom circuits (two-wire) and 178 and 64 (three-wire). Six repeater stations are installed en route, providing for 384 repeaters (161 two-wire and 223 four-wire). The cable is partly aerial and partly underground. Illustrations of repeater stations, poles and towers, and a map of the toll system accompany the paper.