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The first phone was invented
Elon University In 1877-78, the first telephone line was constructed, the first switchboard was created and the first telephone exchange was in operation. -
First transcontinental telephone call
First phonesAlexander Graham Bell makes the first transcontinental telephone call to Thomas Watson-from New York to San Francisco-after trials using De Forest’s triodes successfully boost the long-distance signal. What is the world’s longest telephone line consists of 2,500 tons of copper wire, 130,000 poles, three vacuum-tube repeaters, and countless numbers of loading coils. -
Switching systems and rotary-dial telephones
PhonesBell System companies begin installing switching systems and rotary-dial telephones, though dial phones have been around since just before the turn of the century. The dial makes it easier for customers to place calls without an operator. The finger wheel of the dial interrupts the current in the phone line, creating pulses that correspond to the digits of the number being called. -
Frequency multiplexing concept
PhonesAT&T develops the frequency multiplexing concept, in which frequencies of speech are shifted electronically among various frequency bands to allow several telephone calls at the same time. Metal coaxial cable eventually is used to carry a wide range of frequencies -
this is the seconed Telophone
First Phones covers landline, radio, and cellular telephony technologies and provides many important dates in the history of the telephone -
North American Numbering Plan
PhonesPhonesWith the rapidly growing number of telephone customers, AT&T and Bell Labs develop the North American Numbering Plan, a system that assigns telephone numbers to customers in the United States and its territories as well as Canada and many Caribbean nations. The first three digits of a typical number identify the area being called; the next three, called the prefix, locate the closest central or switching office; and the last four digits represent the line number. Bell Labs conceives the idea of -
A Mathematical Theory of Communication
phones
Bell Labs’s Claude Shannon publishes the landmark paper "A Mathematical Theory of Communication," which provides mathematicians and engineers with the foundation of information theory. The paper seeks to answer questions about how quickly and reliably information can be transmitte -
First phone to combine a ringer and handset
phonesAT&T introduces the Model 500 telephone, the first that combines a ringer and handset. The classic black rotary phone, featuring an adjustable volume control for the bell and later a variety of colors, becomes a cultural icon. -
Direct longdistance calling first available
Phonesn a test in Englewood, New Jersey, customers are able to make long-distance calls within the United States directly, without the assistance of an operator. But it takes another decade for direct long-distance dialing to be available nationwide. -
