GB356815A - Improvements in or relating to telegraphic or like signalling systems - Google Patents

Abstract

356,815. Multiplex tel.egraphy. WESTERN ELECTRIC CO., Ltd., Bush House, Aldwych, London. (Bell Telephone Laboratories, Inc.; 463, West Street, New York, U.S.A.) June 14, 1930, No. 18297. [Classes 40 (iii) and 40 (v).] In a telegraph system in which signals from two or more sources arc repeated into a single cable, the repeater includes a transmitting distributer with live segtments allocated to the several sources and each connected to a condenser which is individual to the segment. Signal impulses from sources C, D are passed through amplifiers 10, 110 to operate relays 11, 111 from the armatures of which positive or negative potentials are applied through brushes 14, 114 to segments a<1>, b<1>, c<1>, . . , a,b,c,.. of receiving distributers 12, 112 respectively. The signal potentials are applied to earthed condensers 20, individual to the segments a<1>, b<1>, c<1>, .. , a, b, c .. of the receiving distributers and individually connected to the live segments a, a<1>, b, b<1>, .. of the transmitting distributer 16, arranged so that the impulses from the several sources to be transmitted to the cable 22 are interleaved. The brushes 14, 114 and 17 are rotated in approximate synchronism, with the transmitting brush 17 behind the receiving brushes 14, 114. The continuous ring 18 of the distributer 16 is connected through a battery 24 to the grid circuit of a valve 23, shunted by u condenser 27 or a resistance 28 according to the position of a switch 26. The potential applied to the grid of the valve 23 from the segments a, a<1>, b, b<1>.. regulates the current in the plate circuit so that impulses to the cable 22 are sent in accord with the impulses received from the sources C, 1). When the grid circuit is shunted by the resistance 28, the plural unit impulses sent into the cable 22 will be broken up as indicated in Fig. 5, by the interposition of dead or insulated segments 19<1> between the live segments 19.