Evolution of Telephones

1 Pages 344 Words

After the invention of the telephone instrument itself, the second greatest technological advance in the industry may have been the invention of automatic switching called Strowger switches, after Almon Brown Strowger, who invented the system because he didn’t trust his town’s human operators were connecting correct calls.
Long-distance telephony was established in small steps.
· The first step was the introduction of the long-distance telephone, originally a special highly efficient instrument permanently installed in a telephone company building and used for calling between cities.
· The invention at the end of the 19th century of the loading coil (a coil of copper wire wound on an iron core and connected to the cable every mile or so) increased the speaking range to approximately 1,000 miles.
· Until the 1910s the long-distance service used repeaters overcome with the invention of the triode vacuum tube, which amplified electrical signals.
And until Direct Distance Dialing became available, all long-distance calls still required the assistance of an operator to complete. By adding a three-digit area code and developing more sophisticated switching machines, it became possible for subscribers to complete their own long-distance calls.
The introduction of radio into the telephone set has been the most important recent development in telephone technology, allowing first the cordless phone and now the cellular phone. In addition to regular telephone service, modern cellular phones also provide wireless Internet connections, enabling users to send and receive electronic mail and search the World Wide Web.
Answering machines and phones with dials that remember several stored numbers (repertory dials) have been available for decades, but because of their expense and unreliability were never as popular as they are today. Multifunctional telephones include automatic answering and message-recording capability.
Videophone...