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DynaTAC is a series of cellular telephones manufactured by Motorola, Inc. from 1984 to 1994. The Motorola DynaTAC 8000X commercial portable cellular phone received approval from the U.S. FCC on September 21, 1983.〔(【引用サイトリンク】title=Motorola DynaTAC 8000X )〕 A full charge took roughly 10 hours, and it offered 30 minutes of talk time.〔" The History of Mobile Phone Technology" RedOrbit〕 It also offered an LED display for dialing or recall of one of 30 phone numbers. It was priced at $3,995 in 1984, its commercial release year, worth a modern-day price of nearly $10,000. DynaTAC was an abbreviation of "Dynamic Adaptive Total Area Coverage." Several models followed, starting in 1985 with the 8000s, and continuing with periodic updates of increasing frequency until 1993's Classic II. Throughout, the DynaTAC was the cell phone, and it became a regular feature in mass media, first as a symbol of wealth and futurism, and later as a quaint throwback when its era had ended. The DynaTAC was replaced in most roles by the much smaller Motorola MicroTAC when it was first introduced in 1989, and by the time of the Motorola StarTAC, it was already obsolete. ==History== The first cellular phone was the culmination of efforts begun at Bell Labs, which first proposed the idea of a cellular system in 1947, and continued to petition the Federal Communications Commission (FCC) for channels through the 1950s and 1960s, and research conducted at Motorola. In 1960, electrical engineer John F. Mitchell,〔(John F. Mitchell Biography )〕〔(The Top Giants in Telephony )〕〔(Who invented the cell phone? )〕 became Motorola's chief engineer for its mobile communication products. Mitchell oversaw the development and marketing of the first pager to use transistors. Motorola had long produced mobile telephones for automobiles that were large and heavy and consumed too much power to allow their use without the automobile's engine running. Mitchell's team, which included Martin Cooper, developed portable cellular telephony, and Mitchell was among the Motorola employees granted a patent for this work in 1973; the first call on the prototype was completed, reportedly, to a wrong number.〔Motorola Executive Helped Spur Cellular Revolution, Oversaw Ill-fated Iridium Project, Wall Street Journal, Remembrances, June 20–21, 2009, p. A10〕 While Motorola was developing the cellular phone itself, during 1968–1983, Bell Labs worked on the system called AMPS, which became the first cellular network in the US. Motorola and others designed cell phones for that and other cellular systems. Martin Cooper, a former general manager for the systems division at Motorola, led a team that produced the DynaTAC 8000x, the first commercially available cellular phone small enough to be easily carried, and made the first phone call from it. Dr. Martin Cooper he was the first person to make an analog cellular mobile phone call on a prototype in 1973. Martin Cooper is considered to be a key developer of the mobile phone. His was the first true portable phone. There were phones before this that were considered to be “car phones” but they were too big to be carried around. The Motorola DynaTAC 8000x was very large compared to phones today. This first cell phone was very expensive when it was released in the USA in 1984. The DynaTAC's retail price, $3,995 (about $ in present-day terms), ensured that it would not become a mass-market item; by 1998, when Mitchell retired, cellphones and associated services made up two thirds of Motorola's $30 billion in revenue.〔John F. Mitchell, Time Magazine Milestones section, July 6, 2009, p.17〕 It wasn’t until later cell phones became smaller, more portable, and more affordable. In 1983 the first flip phone was designed. In 1993 cell phone companies realized that they could use cell phones for different things other than just calling. Developers in Europe came up with the text message. 2002 is when the first smart phone was developed. The smart phone could send and receive emails and messages but it needed a headset to work. The camera phone was also developed; the Sanyo Company developed the first camera phone. In 2007 Apple released the iPhone, which featured a multi-touch display and desktop web browser. On October 13, 1983, David D Meilahn placed the first commercial wireless call on a DynaTAC from his 1983 Mercedes 380SL to Bob Barnett, former president of Ameritech Mobile Communications, who then placed a call on a DynaTAC from inside a Chrysler convertible to the grandson of Alexander Graham Bell, who was in Germany for the event. The call, made at Soldier Field in Chicago, is considered by many as a major turning point in communications. Later, Richard H. Frenkiel, the head of system development at Bell Laboratories, said about the DynaTAC: "It was a real triumph; a great breakthrough." 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Motorola DynaTAC」の詳細全文を読む スポンサード リンク
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