Patent GB-864359-A (GB)
Title: Improvements in and relating to electrical storage arrangements
Inventor: WARMAN BLOOMFIELD JAMES
IPC: G06F3/02
Filed: 1957-08-07
Abstract: 864,359. Automatic exchange systems. ASSOCIATED ELECTRICAL INDUSTRIES Ltd. July 16, 1958 [Aug. 7, 1957], No. 24904/57. Classes 40 (4) and 40 (9). A key sender registers consecutive digits in consecutive columns of a magnetic core storage matrix by marking its row wires, the binary complement of each digit being read out of the store and injected into a counter which is counted out to produce a further complement and hence a pulse train representing the digit decimally. As shown, a pick-up key kpu on the keyboard KS is actuated to switch a transistor trigger pair ST and operate relay SC contacts of which set the component parts of the circuit to a normal condition. Thus the rows of cores RW, RX, RY and RZ are pulsed over a common winding to be reset; an auxiliary row of cores RA is also reset by a pulse and subjected to a set priming bias; while a distributer row of cores connected as a stepping register C1 to C11 has cores C2 to C11 reset but has core C1 set. The keying of a digit marks row wires mw, mx, my, mz to provide a priming bias to a particular combination of rows. Coincident with the marking, a pulse operates a timing circuit TC in which tr5 is cut off and tr6 normally conducts, the transistors switching over after a delay to cover contact bounce. Switching of circuit TC triggers the bi-stable transistor pair DC, the two-phase. output of which is used to step the distributer cores so that C1 is turned over and turns over C2. While C1 drives C2, a transistor gate is opened to drive the column wire associated with C2 and all those cores having a marked row wire are switched. The next key operation advances the distributer to C3 so that the second column takes a digit and so forth. The cores of row RA are invariably switched each time a column is driven. When the whole number is registered the send/release key ksr is operated and triggers a bi-stable transistor pair SN to operate a relay FR. Contacts of FR set core C1 and reset cores C1 to C11 of the distributer, apply a steady priming bias to all the cores of the matrix and start a free running multivibrator IG. Switching of cores in the matrix during registration produce outputs on the wires ow, ox, oy, oz, which result in a number of no significance being set in the fourstage binary counter W, X, Y, Z. Multivibrator IG steps the counter till it triggers a bi-stable pair IP which switches stop-send transistor pair SS to allow de-energization of an impulsing relay PP and steps the distributer so that C1 drives C2 and the first column is interrogated. As all the cores have a priming bias, only those not turned over in registering a digit will turn over now and consequently the output on wires ow, ox, oy, oz is the complement of the original registration and this complement is registered in the four-stage binary counter W, X, Y, Z. Counting out the complement in the counter reproduces the original digit value and each time multivibrator IG steps the counter relay PP is operated under control of its right-hand winding so that its impulse contacts produce pulses with a mark space ratio of 2 : 1 at 10 pulses per second. When the digit is counted out IP is again switched, switching stop-send circuit SS to energize the left-hand winding of PP to hold its impulsing contacts inoperative; while a pulse to a transistor tr15 switches the eleventh column of the matrix which by strapping STR holds a permanent digit and injects this digit into the counter W, X, Y, Z. Multivibrator IG uses this digit to measure out an inter train pause at the end of which IP is again switched to switch SS for re-operation of PP and to step the distributer once more to interrogate the next column of the matrix. This process is repeated until the first column with no digit registered, or the eleventh column, is reached when interrogation switches a core in the row RA producing an output to switch stop send circuit SS. The circuit is released by a second operation of key ksr which switches SN back to normal to release FR.