The Stromberg-Carlson XY Dial Telephone System

This paper describes a flat type of step-by-step switch and its associated equipment which recently has been introduced in the United States for dial telephone switching systems. ``Truly, this (the automatic telephone system) seems the very high-water mark of human creative power.´´ This remark was made by Doctor J. A. Fleming, the eminent British electrical engineer, about 1920 when referring to the step-by-step and other dial telephone systems. The step-by-step system, which previously had been developed by Strowger and others,¹ at that time was being widely installed in England and other locations, both here and in Europe, and since has become the most universally adopted method of dial switching.