"Telegraph and Telephone" Information Transmission PPT Courseware

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"Telegraph and Telephone" Information Transmission PPT Courseware

What is a telegram?

After three years of study by the American painter Morse, the first telegraph machine came out in 1837. Morse successfully used the "on", "off" and "long break" of electric current to replace human words for transmission. This is the famous Morse code. The invention of the telegraph kicked off the telecommunications era and created the history of mankind using electricity to transmit information.

The telephone had an inventor: Alexander Bell

Bell (1847-1922) was an American inventor who built the first telephone in 1876. The first voice was "Watson, come and help me." In 1881, Bell established his own telephone company.

carbon microphone

Carbon microphones, also called carbon receivers, were invented by Edison in 1877. The widespread use of carbon receivers made the original telephone sounds clearer and made telephones truly popular.

The principle of the carbon microphone is that sounds of different intensities produce different pressures, which causes the contact resistance between the carbon particles to change, and the current flowing through the microphone will change accordingly, thus turning the sound into an electrical signal.

Think about it, talk about it

What improvements did the telephone make compared to the telegraph?

What improvements do today's phones have compared to those of the past?

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For more information about the "Transmission of Information Telegraph and Telephone" PPT courseware, please click the "Transmission of Information ppt Telegraph and Telephone ppt" tab.

"Telegraph and Telephone" Information Transmission PPT Courseware 2:

"Telegraph and Telephone" Information Transmission PPT Courseware 2 How to quickly transmit long-distance information? After three years of study by the American painter Morse, the first telegraph machine came out in 1837. Morse successfully replaced human civilization with the on, off and long interruption of electric current.

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Update Time: 2024-09-30

This template belongs to science courseware Hunan Education Edition Fourth Grade Science Volume 1 industry PPT template

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