GB906724A - Improvements in or relating to electrical signal classifying equipment - Google Patents

Abstract

906,724. Electronic counting-apparatus. NATIONAL RESEARCH DEVELOPMENT CORPORATION. Sept. 1, 1960 [Sept. 9, 1959], No. 30828/59. Class 106 (1). Apparatus for counting separately the number of electrical pulses lying in a plurality of categories formed by predetermined amplitude ranges comprises means for identifying the category of a signal by a time scale, the counter comprising a main circulatory store for the higher denomination adapted to receive at intervals counts from a subsidiary circulating store operating in synchronism with said time scale for the lower denominations. The invention may be applied to the pulse analyser described in Specification 715,816. In a first embodiment, Fig. 1, a counter is designed to provide 260 category channels each with a capacity of 5 binary-coded decimal digits and comprises a main circulatory store 2 for the five digits and a circulatory store 1 for the units digit. The store 1 comprises four individual delay loops 3-6, each having 273 bit positions, thirteen additional positions being provided to allow for fly-back time in a comparison sawtooth waveform. The main store 2 comprises two delay loops 10, 11 each having 2,730 bit positions, each binary coded 4-element decimal digit occupying two bit positions, 2‹, 2<SP>1</SP> in the loop 10, in parallel with 2<SP>2</SP>, 2<SP>3</SP> in the loop 11. The ratio of circulation times of the stores 1, 2 is 1: 10. An input pulse in a particular channel appears on a terminal 8 and is added into the channel then incident at an adder 7. At the beginning of every ten bit times of the main store 2, an electronic switch 13 is operated to transfer a binary coded decimal digit from the store 1 to the corresponding channel in the store 2 where it is added into the count there circulating by an adder 12, the 2‹ and 2<SP>1</SP> bits being fed sequentially to the loop 10 and the 2<SP>2</SP> and 2<SP>3</SP> bits to the loop 11. Outputs 18 are fed to a display or printing device and the store 2 may be reset by a switch 19. The adder 12 may be replaced by a subtractor if it is desired to perform subtractive counts. In a modification (Fig. 2, not shown), only the carry from the adder 7 is transferred to the main store 2 so that the subsidiary store 1 always retains the units denominational digit.