Презентация на тему История создания телефона

the most interesting and widely-used inventions is the telephone.

The modern phone that we use today is the result of work of many people. 

in 1876 was Alexander Graham Bell. He is credited

as the inventor of this practical device. Other scientists who also worked on telephone invention were Elisha Gray, Antonio Meucci, Thomas Edison and some others. 

and were runners postal birds . Also, as a

means of communication used by the smoke , fire, specially trained criers . In the XVI century Italian scientist Giovanni della Porta proposed to establish a system of negotiating pipes laid across Italy . However, his idea was not supported and has not been put into practice . In 1837, American inventor Samuel Morse invented the transmitting machine - the electric telegraph and invented a system of codes - telegraph Morse ( Morse code ) .In 1861, German scientist Philip Rice invented a device capable of transmitting sound over a distance on the wire. In fact, this was the first phone . However, discoverer of the phone got amerikanskomuTelefon inventor Alexander Graham Bell Bell patented his telephone February 14, 1876 . Simultaneously with an application for a similar device , another American inventor filed Elish Gray. But since it was filed on 2 hours later , a patent was issued Graham Bell . Later, Gray filed a case against the opponent , but lost it. But despite the inconsistency of this discovery , it marked the beginning of a new era in the field of communications - telephony era .

entering the circuit induction coil and the carbon microphone

. This has greatly increased the distance between subscribers . In the same year, was commissioned first telephone exchange in a small American city of New Cheyven . In 1887, Russian inventor K.A.Mostsitsky created automatic switch, which foreshadowed the creation of automatic telephone exchanges . By the way the first audio message transmitted by telephone Bell was: "Mr. Watson, come here , I need you . " In Russia, the first telephone conversation took place in 1879

development and modernization. Rotary telephones were replaced by touch-tone

dials and other sophisticated features. Modern phones are presented mostly by mobiles, which support IP telephony and wi-fi.

nowadays who doesn’t have a personal mobile phone. These

phones have become highly popular over the last years. They are rather compact, handy and easy to carry around.

send text messages, listen to music, play games, take

photos, check an e-mail and else. Thus, they have replaced not only landlines but also personal computers, MP3-players and cameras.

who are against mobiles phones. Doctors claim that this

device has a bad effect on people’s health. It can damage our eyesight and immune system. The signals that are sent from mobiles can be harmful.

communication. And, it is true. With the appearance of

mobile phones and computers people meet up with friends less often

and important device. We simply can’t live without it

in the modern world, even though it is not safe for health. The only solution is to try to use it less in everyday life.

phones are an integral part of life of any

person and we can’t stop it. I personally need it everyday for my work and to keep in touch with my friends and relatives, though I’m aware of its deleterious influence on my health. But I try to avoid idle talks on the phone to reduce the influence of harmful radio waves. I try to find the happy mean.