Patent GB-812566-A (GB)
Title: Improvements relating to translating apparatus as employed in automatic telephone and like systems
Inventor: WARMAN BLOOMFIELD JAMES
IPC: H04Q3/00
Filed: 1956-07-12
Abstract: 812,566. Automatic exchange systems. SIEMENS EDISON SWAN Ltd. July 12, 1957 [July 12, 1956], No. 21597/56. Class 40 (4). In a translator, which may be common to a plurality of registers, the cross-connection field has on its input side one code point for each different code to be catered for, and on its output side a group of translation terminals for each of the digit values 1, 2... 0, each group including a translation terminal for each translation digit (viz. first, second ...) capable of having such value, each code point being connected to the translation terminals corresponding to the digits of the translation for that code in the groups corresponding to the respective values of those digits, there also being provided means responsive to the reception of a code to mark the corresponding code point, and an output circuit for each group of translation terminals including amplifying means having individual and mutually isolated input connections from the respective translation terminals of the group concerned. The amplifying means employed consists of saturable reactors or pulse transformers. Arrangement of cross-connection frame, Fig. 1. It is assumed that translations of up to eight decimal digits have to be provided, one digit at a time, for codes of either three or six decimal digits each. The sixty input terminals IT are therefore divided into six groups CG1, CG2 ... CG6, each relating to a particular digit (e.g. first, second ... sixth) of an exchange code while each of the ten terminals IT1 ...IT0 in a group relates to a particular value (1,2 ... 9, 0) of the code digit to which the group relates. For each code point there is provided a gate such as G1 ... G4 which is either a coincidence-of-three gate such as G1, G2, G3, or a coincidence-of-six gate such as G4, according as the code to which the code point relates is a three digit or a six digit one. Each code point is also connected to eight output points OP1-OP8, one per translation digit, via respective isolating rectifiers RF, and these eight points OP are respectively cross-connected over the field TF to the relevant eight translation terminals. In the normal condition all the input terminals IT are at ground potential, those relating to a received code being raised in potential, as described below with reference to Fig. 6, on receipt of the code so as to raise the potential of the corresponding code point. Output circuits, Fig. 2.-Eighty saturable reactors 1SR1 to 8SRO corresponding to the eighty translation terminals TT are divided into ten groups SRG1 ... SRG0, each relating to a particular translation digit value as indicated by the numeral in the group reference and also by the numerical suffix in the reactor references themselves. The saturable reactors in any one group relate to the eight translation digits as indicated by the numerical prefixes 1-8 in the reactor references. Only three reactor groups SRG1, SRG5 and SRGO are shown, and only the first, second and last reactor in each group. The control winding CW of each saturable reactor is connected between the translation terminal TT to which the reactor corresponds and that one of the eight digit selection wires DS1 ...DS8 pertaining to tho particular translation digit (first, second ...) to which the reactor relates in its group. For example, the winding CW of 2SR5 in group SRG5, which relates to a value five for the second translation digit, is connected between the second terminal TT2 in group TG5 and the wire DS2 relating to the second translation digit. The output windings W of the reactors in each group are coupled to a common storage or utilization element, such as the cold cathode tube VT1, which pertains to the digit value of the group, via individual decoupling rectifiers such as Rf5. OperationFigs. 1, 2.-The digit selection wires DS1 ... DS8 are normally held unmarked at a potential more positive than the code point marking potential so that all the rectifiers RF (Fig. 1) are backed off. To select a particular translation digit the corresponding selection wire is marked by changing its potential to a value between the marked and unmarked potentials of the code points, so that of the rectifier RF connected to that selection wire, those connected to unmarked code points remain backed off, but the one connected to a code point marked in response to the reception of a code will be rendered conductive. The saturable reactor SR relating to the particular value of the chosen digit in the required translation responds to the consequent flow of current in its control winding, the resulting output current firing the relevant tube such as VT1 indicative of the value of the digit. Modified<SP> </SP>forms of output circuits.-In the modification of Fig. 3 (not shown), each group of eight saturable reactors such as SRG1 (Fig. 2) is replaced by a single saturable reactor having eight control windings and a single output winding. The cold cathode tubes such as VT1 (Fig. 2) may be replaced by relays. In the modification of Fig. 4 (not shown), each group of eight saturable reactors such as SRG1 (Fig. 2) is replaced by a group of eight pulse transformers, and in that of Fig. 5 (not shown) by a single pulse transformer having eight input windings and a single output winding. Marking the inputterminalscorresponding to a received code, Fig. 6.-The input terminals IT are connected to the cathodes of respective cold cathode tubes such as VTM in the register, each cathode being connected to ground through an individual resistance such as R4 so that in the normal state (tubes VTM non- conducting) the input terminals IT are at ground potential. In response to received digital signals a combination of tubes such as VTM (one from each group) is fired, and the resulting positive potential at the cathodes of the fired tubes provides the required marking of the input terminals IT. Eight further cold cathode tubes such as VTD are associated with the digit selecting wires DS1 ... DS8. The anode of each such tube is connected via an individual load resistance such as R5 to a positive H.T. supply terminal, the digit selection wires being connected either to the tube anodes as shown, or to intermediate points in the load resistances depending upon the magnitude of the required marking potential. With the tube VTD non-conducting the corresponding wire of DS1 ... DS8 is at the positive potential of the H.T. supply; firing of one of these tubes changes the potential of the corresponding wire to a lower value. Another method of marking the input terminals which employs relay is described with reference to Fig. 7 (not shown).