Search results
Results from the WOW.Com Content Network
One of the jobs of outside plant personnel was to visit each telephone periodically to inspect the battery. During the 20th century, the "common battery" operation came to dominate, and was powered by the "talk battery" from the telephone exchange over the same wires that carried the voice signals. Late in the century, wireless handsets brought ...
The telephone played a major communications role in American history from the 1876 publication of its first patent by Alexander Graham Bell onward. In the 20th century the American Telephone and Telegraph Company (AT&T) dominated the telecommunication market as the at times largest company in the world, until it was broken up in 1982 and replaced by a system of competitors.
A sound-powered telephone is a communication device that allows users to talk to each other with the use of a handset, similar to a conventional telephone, but without the use of external power. This technology has been used since at least 1944 [ 1 ] for both routine and emergency communication on ships to allow communication between key ...
The introduction of nickel and lithium based batteries in the latter half of the 20th century made the development of innumerable portable electronic devices feasible, from powerful flashlights to mobile phones. Very large stationary batteries find some applications in grid energy storage, helping to stabilize electric power distribution networks.
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.
Nov. 2—This weekend marks the end of daylight saving time and clocks will be turned back one hour on Nov. 5. This occasion also serves as a good time to check some important equipment in your ...
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.
Daylight saving time ended on Sunday. If you forgot to replace your smoke and carbon monoxide detector batteries, why not replace them today?