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This was the first automatic telephone exchange to be installed anywhere, and a considerable amount of ceremony was attached to the affair, with a special train run from Chicago and a brass band on hand to greet the guests. When his system made its debut, Almon Strowger bragged that his exchanges were "girl-less, cuss-less, out-of-order-less, and wait-less." It required users to tap out the number they wanted on three keys to call other users directly. The system worked with reasonable accuracy when the subscribers operated their push buttons correctly and remembered to press the release button after a conversation was finished, but there was no provision against a subscriber being connected to a busy line. In 1896 the 'tapper' keys were replaced by a dial similar to the ones that would be used on telephones for the next 80 years. 

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The engineers of the Automatic Electric Company continued to make improvements in the Strowger system (now called step-by-step), while the Bell System engineers developed the panel type of machine switching system. After World War I step-by-step equipment was generally deployed for small and medium size cities while panel was deployed in the largest ones. Strowger's company was eventually consumed by the giants of the telecommunications industry; having been owned at one time or another by AT&T, Verizon, GTE & Lucent and ultimately Siemens. The engineering involved in the development of the original mechanical switches is truely amazing, but is quickly becoming a lost art. The oldest still operating Strowger mechanical switch is at a traditional summer boys camp in the mountains of northeastern Pennsylvania. Debates about Strowger technology still rage on Yahoo groups.