Push-button telephone
The push-button telephone was first invented in 1941, and is a telephone with push-buttons or keys, and which eventually replaced rotary dial telephones that were first used in 1891.[1] The first push-button telephone was invented in the labs of Bell Telephone; however, these models were only prototypes, and were not brought to the commercial market.[2] The first publicly-available push-button telephone was released in 1963, by the Bell System. They were first made available in the towns of Carnegie and Greensburg, Pennsylvania.[3]
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[edit] History
In the 1950s, AT&T conducted extensive studies, and concluded that push-button dialing was much faster than rotary dialing.[4] On November 18, 1963, the first electronic push-button system, with Touch-Tone dialing, was offered by Bell Telephones to AT&T customers.[4][5]
The push-button telephone was introduced to the public, in the towns of Carnegie and Greensburg, Pennsylvania, with touch-tone dialing available for an extra charge.[3] The first push-button phone, the Western 1500, had only ten buttons. A twelve-button model featuring the asterisk/star (*) and pound/hash (#) keys was released soon afterwards, replacing the earlier model.
Though push-button touch-tone phones made their debut to the general public in 1963, the older rotary dial telephone still was common for many years. In the 1970s, the majority of phone users still had rotary phones. Adoption of the push-button phone was steady, but it took a long time for them to appear in some areas.[6] At first it was primarily businesses that adopted push-button phones.[7] By 1979, the touch-tone phone was gaining popularity,[7] but it wasn't until the 1980s that the majority of customers owned push-button telephones in their homes; by the 1990s, it was the overwhelming majority.
Some exchanges no longer support pulse-dialing,[6] and rotary telephones are generally considered obsolete.[8][9] Rotary telephones are now largely considered a novelty,[10] and are not compatible with some modern telephone features, though enthusiasts may adapt pulse-dialing telephones using a pulse-to-tone converter.[11]
[edit] Touch-tone
For optimum use, push-button phones utilize dual-tone multi-frequency (DTMF) signaling, more commonly known as touch-tone dialing, rather than the older and slower pulse dial system.[12][13] Touch-tone technology was first made available in 1963 with the introduction of the first push-button telephone, though pulse-dialing was still supported by many telephone exchanges.[3] The touch-tone format quickly became the standard dialing system in the United States, especially in the business market,[7] and eventually became the standard worldwide.[4] The push-button touch-tone format is also used for all cell phones.[7]
The telephone buttons are typically arranged in a 3-by-4 grid, including the digits zero through nine, in addition to the star key (*) and the pound/hash sign (#) to accommodate various additional services and customer-controlled calling features.[3][4] Specific frequencies are assigned to each column and row of push-buttons in the telephone keypad; the columns in the push-button pad have higher tones, and rows in the pad have lower tones. When one of the buttons is pressed, a dual-tone signal is generated, based on the frequencies for the selected row and column. A signal representing that tone is then transmitted over the phone line to the telephone exchange.[4]
[edit] Features
Push-button telephones have allowed for advancement in telecommunications.[2][5] Telephones and telecommunications networks have benefited from continued advancements in digital electronics.[12][14] Electronics within the push-button telephone provides for last number re-dial and storage of commonly called numbers. 'Caller line identification' or "Caller-ID", allows the number of the caller to be displayed on the telephone handset. Some models support additional features, such as retrieval of information and data or code and PIN entry.[15] Push-button telephones also allow for Internet-based telecommunications such as VoIP.[11]
[edit] See also
- History of the telephone
- Keypad
- Mobile phone
- Pulse dialing
- Rotary dial
- Telephone
- Telephone keypad
- Touch-tone (DTMF)
- VoIP
[edit] References
- ^ The New York Times - "When Dials Were Round and Clicks Were Plentiful"- by Catherine Greenman, October, 1999
- ^ a b Push. Click. Touch. - History of the Button - 1963: Pushbutton Telephone - December 11, 2006
- ^ a b c d Great Achievements-Telephone Timeline
- ^ a b c d e Britannica. - Call number dialing
- ^ a b Engineering Pathway - Bell Telephone introduces push button telephone - by Alice Agogino - November 18th, 2009
- ^ a b I Remember JFK - Push-Button Telephones
- ^ a b c d Wise Geek - What is a Touch Tone Telephone?
- ^ TimesDaily.com - Advances make many items close to obsolete - by Tom Smith & Bernie Delinski - October 14, 2009 - Retrieved February 10, 2010
- ^ The Free Lance-Star - Aug 12, 1994, by Michael Zitz, page 1 - Rotary phone users in info highway's slow lane
- ^ Sacramento Business Journal - Rotary phones ring true for few - all but gone from workplace - March 9, 2001
- ^ a b oldphoneworks
- ^ a b University of Salford - Computer Networking and Telecommunications Research - General Telephones
- ^ Wise Geek - What is a Rotary Phone?
- ^ An (Incomplete) History of Digital Technology - 2010 - East Hartford Public Schools
- ^ Mobile Phone As Home Computer - Philip Greenspun
