CIRCUIT ARRANGEMENT FOR DETERMINING SUBSCRIBER CALL NUMBERS IN TELEPHONE SYSTEMS

1,013,269. Automatic exchange systems. SIEMENS & HALSKE A.G. Oct. 1, 1962 [Sept. 29, 1961], No. 37024/62. Heading H4K. In a calling line identifying arrangement in which a conductor AWS individual to each line is threaded selectively through one ring core in each of four columns of cores, one column for each digit, so as to give an output which represents the number of the line, four identifying units AF1 . . . AF4 serve different groups of lines and a preliminary test determines the unit to be effective. For this purpose the threaded loops in the four units are taken through cores K1 . . . K4 in order to operate one of the receivers S6 . . . S3 in the common equipment SO . . . S9, and these control relays to complete the output connections AK1 . . . AK4 of the relevant unit. In addition the loops may include a core OM or Hot to given an appropriate " class " indication for call-box lines and hotel lines. In the case of lines incoming from a sub-exchange the loops pass through a core UA if the subexchange contains no identifying equipment, or through a core UA1 or UA2 if it does, and the operative core then gives an indication as to whether one or two code digits are to be received. The cores K1 . . . K4 may identify party-line subscribers. Specifications 1,009,069 and 1,012,784 are referred to.