Telephone invention

Слайд 2

Telephone Invention

Just like a radio invention, lots of inventors and scientists took

Telephone Invention Just like a radio invention, lots of inventors and scientists
part in a telephone invention. Right now the official telephone inventor is Antonio Meucci, an Italian scientist, who was the first one to publish telephone device in 1860.In 1861, another scientist Johann Philipp Reis demonstrated a device that looked like a phone. After a telephone was invented it was constantly improved. The ring was made as well as a button microphone, rotary and push-button dial, a speaker and so on. In 1973, a cell phone was invented. The first phone call was made by the inventor Martin Cooper who derisively call his competitor Joel Engel from AT&T on April 3, 1973. Martin was working in Motorola back then. The first cell phone weighted over 1 kg and was very big plus you had to charge it for more than 10 hours.

Слайд 3

Johann Philipp Reis

Johann Philipp Reis (born January 7, 1834 – died

Johann Philipp Reis Johann Philipp Reis (born January 7, 1834 – died
January 14, 1874) was a self-taught German scientist and inventor. In 1861, he constructed the first make-and-break telephone, today called the Reis telephone.
Имя файла: Telephone-invention.pptx
Количество просмотров: 52
Количество скачиваний: 0