Abstract: A multiplicity of subscriber lines, originating at telephone stations equipped partly with dials and partly with keyboard-controlled multifrequency generators, are connected to pulse-responsive selection equipment by way of switching circuits which are under the control of respective key-signal detectors. Upon the operation of any multifrenquency generator, the latter emits a key signal which actuates the associated detector to switch that line to a conversion network wherein the incoming frequency combinations are translated into binary codes which are stored in a dynamic memory whence they are read out into an available binary/decimal converter. The stored binary codes are accompanied by a line address which enables a coupler to reinsert the selection signals, in the form of digital pulse trains, into the correct line with the aid of an associated interface unit.

Abstract: A network for the temporary storage of binary code words, such as calling digits accompanied by line-identification signals in a telecommunication system, includes a multistage shift register together with a one-stage buffer register and a one-stage extraction register, each stage accommodating a multiplicity of calling and identification bits together with a discriminating bit indicating the availability or non-availability of an outgoing channel to which the accompanying code word is to be transmitted. The three registers are cascaded in a loop for continuous recirculation in a recurrent cycle of z time slots, z being the number of register stages (514 in the specific example given), of the code words accompanied by availability bits; the code words are read out from the loop between the extraction and buffer registers.