The AE Strowger Dial Candlestick
11-digit dial telephone, circa 1905
A Kansas City (Kansas) inventor named Almon Strowger invented the first automatic dial telephone system in 1889. This system used rotary relay switches that followed pulses in the central office when a subscriber moved a dial on the telephone. This type of system was called step-by-step or simply step. (See How Phones Work
in the Science wing for more about Strowger.)
By 1892, the first Strowger Automatic Telephone Exchange was in service in La Porte, Indiana. It served fewer than 100 subscribers, but it proved the concept. In 1901, the Automatic Electric company was formed, which licensed Strowger’s step-by-step automatic switching equipment. The telephone on display here is an early Automatic Electric telephone designed for use with a Strowger exchange. It was made around 1905. Note that the dial has eleven digits—the numbers 0 through 9 plus an additional dial position to reach the operator. Operator assistance was required, of course, to place calls outside the local exchange. In 1908, Automatic Electric bought out Strowger’s company. Automatic Electric continued to manufacture improved versions of this type of step-switch for decades thereafter. Typically, these step offices were sold to independent telephone companies, often in smaller cities and towns. Step-by-step technology was best suited to small offices with relatively light telephone traffic. The Bell System initially considered step-by-step systems but decided instead to develop a more technologically advanced switch called a panel switch. The panel switch was more suited to the heavy telephone traffic found in large cities.
By the end of the 1920s, dial telephone service had come to most large cities. If a city was served by the Bell System, dial service was likely provided by a panel switch built by Western Electric and maintained by the local Bell Operating company. Although the Bell System did not pursue the design of step equipment, it did install step systems in smaller cities and towns. Until the 1930s, the Bell System either purchased Automatic Electric equipment or used step-by-step equipment made by Western Electric under Automatic Electric license. Western Electric continued to build step-by-step equipment until the 1970s. We have examples of both panel and step offices on the 3rd floor of the Museum of Communications.
The French Candlestick
Our visitors have been inspired to go through their attics and basements and come up with some rather unique items. This one is a French Candlestick.
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