Search results
Results from the WOW.Com Content Network
The history of mobile telephony in Brazil began on 30 December 1990, when the Cellular Mobile System began operating in the city of Rio de Janeiro, with a capacity for 10,000 terminals. At that time, according to Anatel (the national telecommunications agency), there were 667 devices in the country.
Telephone centers in the city of Rio de Janeiro (1976). Between 1966 and 1971, 129,000 telephone terminals were installed, rotary exchanges were expanded and new Pentaconta 1000 (Standard Electrica) crossbar exchanges equipped for the DDD system were set up. The plan's first telephone exchange was inaugurated in December 1966 in Copacabana ("56 ...
11 February 1876: Elisha Gray invents a liquid transmitter for use with a telephone, but he did not make one. 14 February 1876 about 9:30 am: Gray or his lawyer brings Gray's patent caveat for the telephone to the Washington, D.C. Patent Office (a caveat was a notice of intention to file a patent application.
Telephone technology grew quickly after the first commercial services emerged, with inter-city lines being built and telephone exchanges in every major city of the United States by the mid-1880s. [ 17 ] [ 18 ] [ 19 ] The first transcontinental telephone call occurred on January 25, 1915.
According to Carlos Henrique Moreira (president of Embratel), in the eight years after the privatization, from 1998 to 2006, the fixed and mobile telephone subscriber base increased by 27.4 million to 139 million, at an annual rate of 20%, generating an annual increase of income of 18%, from R$31 billion to R$121 billion). The government's tax ...
As phone lines became more popular—between 1942 and 1962, the number of phones in the U.S. grew 230% to 76 million—telephone companies realized they would run out of phone numbers.
A tin can phone is a type of acoustic (non-electrical) speech-transmitting device made up of two tin cans, paper cups or similarly shaped items attached to either end of a taut string or wire. It is a particular case of mechanical telephony , where sound (i.e., vibrations in the air) is converted into vibrations along a liquid or solid medium .
The early history of the telephone became and still remains a confusing morass of claims and counterclaims, which were not clarified by the huge number of lawsuits filed in order to resolve the patent claims of the many individuals and commercial competitors. The Bell and Edison patents, however, were commercially decisive, because they ...