Telephone

TELEPHONE



Telephone was created by Alexandra Graham Bell in Faraday 1830. He got the patent in 1876.

Telephone signals were sent by two way radio connection until 1960s.At second part of 19th Century, rough and complicated telegram nets resulted some inquiries upon long distance communication.

The most important problem which engineers usually faced with was that signals were almost stopping on halfway of the net .Bringing them together, classic radio signals and modern micro waves; this problem was solved in the second half on 20th Century. However, cables are rarely used for such connections at present but in last decade of the century communication have been provided in space by using satellites. Micro waves and superficial satellites help us 7to get clear voices and visions despite long distances among different areas.



TELEPHONE CENTRALS


At the beginning, telephone calls and connections had been providing by an operator who were using some simple devices for communication. First automatic connection was held in 1889 and first automatic board made of some mechanic devices was set up in States in 1921.