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In telephony and telecommunications in connection with a telephone, a dial refers, in older telephones, to a rotating disk with 10 numbered finger holes. When a particular numbered hole is rotated with the finger to a finger stop set at a specific point across the dial, then released, the dial mechanism rotates the dial back to its original position and transmits pulses down the telephone line according to the number of the hole selected.
Nowadays the dial is a key pad, generally with 12 keys numbered 1-9,*,0,#, that performs an equivalent signalling function to that of a rotating disk dial.
In similar use in telephony, the word dial (in present and past tense spelt with two "l"s in British English and with one in American English) describes the process of the placement of a telephone call.
From as early as 1836, there were various suggestions and inventions of dials for sending telegraph signals. After the first commercial telephone exchange was installed in 1878, the need for a telephone dial became apparent. The first telephone dial patent was jointly issued to Connolly and McTighe in 1879. There were numerous competing inventions, and 26 patents of dials, push-buttons and similar mechanisms for signalling which telephone subscriber was wanted by a caller were issued prior to 1891. Most involved highly complex, and expensive, mechanisms and required the user to perform complex manipulations.
The first commercial installation of a Telephone Dial accompanied the first commercial installation of a 99 line automatic telephone exchange in La Porte, Indiana in 1892Events January 1 Ellis Island begins accepting immigrants to the United States. January 14 Death of Prince Albert Victor, Duke of Clarence, second in line heir to the throne of the United Kingdom of Great Britain and Ireland. Next in line is his younger b, which was based on the 1891 StrowgerAlmon Brown Strowger ( 1839 May 26, 1902) gave his name to the electromechanical telephone exchange technology that his invention and patent inspired. He was born in Penfield, near Rochester, New York. Little information is available about his early life. patentA patent is a set of exclusive rights granted by a government to an inventor or applicant for a limited amount of time (normally 20 years from the filing date). The term "patent" originates from the term patere which means to lay open (to public inspectio designs. The original dial designs were rather cumbersome and development continued during the 1890's and early 1900's hand in hand with the switching technology. In the 1950Events January January 5 US Senator Estes Kefauver introduces a resolution calling for examination of organized crime in the USA January 6 The United Kingdom recognizes the People's Republic of China. The Republic of China severs diplomatic relations with's, invention of plastics saw the dial itself change from metal disk to a plastic ring.
The dial numbering can occur in 4 different formats, with 0 either being placed next to the 1 or the 9 and the numbers running in ascending or decending order with either the 0,1 or 9 being closest to the fingerstop. However, the number of pulses sent by the dial remained the same with one hole movement sending one pulse and 10 hole movements sending 10 pulses. All the telephones connected to a particular telephone exchange had to have the same dial numbering. Generally dial numbering was standardised on a countrywide basis, though all 4 dial formats were used.
In the early 1960sCenturies: 19th century 20th century 21st century Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s 2000s 2010s Years: 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 Events and trends The 1960s was a turbulent decade of change around Bell Telephone Laboratories researched various key pad layouts to replace the telephone dial, for electronic telephone equipment. Researchers rearranged the dial numbers in a wide range of combinations from mimicing a telephone dial to the now familiar 4 row by 3 column keypad. They found the 4x3 keypad to be the fastest and most error free arrangement to operate. However, because the American telephone dial had the 0 next to the 9, they tested the arrangement with a 1 at the top and 0 at the bottom, below the 8 key. They also tested an arrangement with the 0 below the 2 and having 9 at the top, as appeared on adding machines at that time and now appears on computer and calculator keyboards, but that arrangement was more error prone as few people were familiar with adding machines at that time. Because of this research, phone key pad numbering is reversed to today's calculator and computer keyboards.