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mobile cell phone evolution

Mobile Cell Phone Evolution

History
Radiophones have a long and varied history going back to Reginald Fessenden's invention and shore-to-ship demonstration of radio telephony, through the Second World War with military use of radio telephony links and civil services in the 1950s.
The first mobile telephone call made from a car occurred in St. Louis, Missouri, USA on June 17, 1946, using the Bell System's Mobile Telephone Service, but the system was impractical from what is considered a portable handset today. The equipment weighed 80 pounds (36 kg), and the AT&T service, basically a massive party line, cost US$30 per month (equal to $337.33 today) plus 30–40 cents per local call, equal to $3.37 to $4.5 today.
In 1956, the world’s first partly automatic car phone system, Mobile System A (MTA), was launched in Sweden. MTA phones were composed of vacuum tubes and relays, and had a weight of 40 kg. In 1962, a more modern version called Mobile System B (MTB) was launched, which was a push-button telephone, and which used transistors to enhance the telephone’s calling capacity and improve its operational reliability, thereby reducing the weight of the apparatus to 10 kg. In 1971, the MTD version was launched, opening for several different brands of equipment and gaining commercial success.

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Filename:474172.jpg
Album name:Architecture & Design
Rating (1 votes):55555
Keywords:#mobile #cell #phone #evolution
Filesize:48 KiB
Date added:Apr 25, 2012
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