GB600503A - Improvements in or relating to calculating or like accumulators comprising electronic devices - Google Patents

Abstract

600,503. Pulse counting circuits. NATIONAL CASH REGISTER CO. May 19, 1944, No. 9742. Convention date, Sept. 26, 1941. [Class 40 (vi)] In a counting-circuit, a number of pairs of valves are arranged in trigger circuits, pulses being applied to the control grids of all the valves, the pairs being so coupled that they operate in sequence, one pair only reversing in response to a pulse. The control grids of valves 0, 6, 7, 8 and 9 are temporarily earthed, the shading indicating the conducting state, the corresponding valve of the pair being rendered non-conducting, due to the interconnection of the anodes and control grids. The suppressor grid of valve 0 is coupled over condenser 90 to the control grid of valve 6, similar connections being made between the other valves. The first pulse, applied over terminal 95, is fed to the suppressor grid of all the valves over coupling condensers 97 ... 106, the pulses being lost, due to suppressor grid current in the conducting valves and ineffective in the non-conducting valves, with the exception of that applied to valve 5 which, due to coupling over condenser 107 causes the control grid potential of valve 1 to rise and the pair 1, 6 to reverse. Each succeeding pulse continues this process, the tenth pulse causing valve 5 to be cut-off and valve 0 to conduct. A connection may be taken from the anode of valve 5 to produce a positive pulse which is fed to a tens counter. In a modification, Fig. 3 (not shown), the incoming pulses are applied directly to the control grids of each valve, the coupling condensers corresponding to condenser 90 being made larger in order that the suppressor grid current may produce sufficient attenuation. The anode potentials may be scanned by a rotary switch to locate a conducting valve or valves and control an indicator.