assembly to receive and operate different signalling patterns.in particular, the characterization is used in the transmission of information in digital telecommunications facilities

摘要

906,158. Electric selective signalling systems. SIEMENS & HALSKE A.G. March 9, 1959 [March 10, 1958], No. 8074/59. Class 40 (1). [Also in Group XXXVI] In an arrangement for evaluating signal currents of different values such as the characterization of digits in a telephone system, there is provided at the receiver a plurality of magnetic devices EW1, VW1, AW1; EW2, VW2, AW2; EW3, VW3, AW3, in each of which a comparison is made between a magnetic flux of constant value provided from a source U and a magnetic flux generated by the current to be evaluated in line L, the currents being switched on or off by a transistor switch TR1 to effect the comparison and produce an output pulse in one or more output windings AW1, AW2, AW3 according to the current value. The pulses are applied to trigger bi-stable circuits TK1, TK2, TK3, through transistor amplifiers V1, V2, V3, when a second transistor switch TR2 is rendered conductive, a switch T being provided to reset the bi-stable circuits. Rectifiers EG1-EG3 decouple the different current value stages, and rectifiers AG1-AG3 short circuit pulses not required for evaluation so that the bi-stable circuits respond only to one polarity of current difference.