GB377968A - Improvements in electric telegraph and like signalling systems - Google Patents

Abstract

377,968. Code telegraphy. ELECTRICAL RESEARCH PRODUCTS, Inc., 195, Broadway, New York, U.S.A.-(Assignees of Burton, E. T.; 97, Cypress Street, Millburn, New Jersey, U.S.A.) April 30, 1931, No. 12761. Convention date, April 30, 1930. [Class 40 (iii).] Distorted signals are reshaped and repeated, independently of their relative strength, bymeans comprising transformers of the impulse coil type acting upon polarized unbiased electromagnetic relays. The signals received from cable 11 are passed through a shaping network 12 of the kind described in Specification 248,823, [Class 40 (iii), Telegraphs, Electric], and through a low-current valve and shaping networks 13, 16, 15, 18 to oppositely biased transformer coils 21, 22 whose cores have high permeability for small magnetizing fields and are readily saturated, as described in Specification 312,904, [Class 40 (iii). Telegraphs, Electric]. The impulses applied to the coils 21, 22 are shown at b, and the intensities at which the cores of 21, 22 respectively become saturated are shown at b21, b22 respectively. The biases are therefore such that positive and negative input impulses respectively affect coils 21 and 22, producing pairs of opposite output impulses as at c and at d respectively. These impulses are passed on by a two-stage large-current push-pull amplifier 24, 26 to the pair of polarized unbiased relays 32, 33 whose armatures are thereby set to give outputs e, f respectively. The combined output at terminals 34 is as shown at g. Impulses are also applied through terminals 19, 20 to a zero-correcting circuit 35 of the kind described in Specification 315,821, [Class 40 (iii), Telegraphs, Electric].