GB257001A - Improvements in or relating to synchronous telegraph systems - Google Patents

Abstract

257,001. Muirhead &. Co., Ltd., Muirhead, F. H., Heurtley, E. S., and Foll, J. V. May 14, 1925. Synchronous movements. - In a system in which retransmitting or recording apparatus is maintained in synchronism by the received signals, the correcting coil is short-circuited during the intermittent closing of its series circuit except when a correcting impulse is required, the series and shunt circuits being under the. joint control of synchronized contact mechanism and of mechanism actuated by the received signals. In one arrangement, Fig. 1, (Comp.), the series circuit D<1> of the correcting coil C is closed intermittently by a contact lever B operated by a cam on a synchronized shaft, and the shunt circuit D<2> is closed except when the tongue f of a relay F is momentarily operated in response to a received signal. In a modification, Fig. 2, the shunt circuit is closed by the tongue f of a relay F<1> moved in opposite directions by the energizing of the dot and dash coils f<6> by the received signals, the tongue being held against either of its contacts f<7> by a biasing device f<8>. The Provisional Specification describes also an arrangement, Fig. 1, (Prov.), in which the coil C is in a circuit including in series the contact intermittently closed by the lever B and a contact closed at f<3> by the tongue f of a relay F whenever this relay is energized. The coil of relay F is in series with a battery g', a condenser g, and the tongue e and one contact e<2> of the relay E which receives the signals, the other contact e<1> being connected to the side of the condenser remote from the tongue e. The relay F is thus energized momentarily during the charging of the condenser when the tongue e makes contact at e<2>, and the condenser is subsequently discharged through the contact e<1>.