On 7 March 1876, Scottish-born Canadian-American Alexander Graham Bell (1847-1922) was granted a patent for the "magneto-electric telephone". Still considered perhaps the most valuable invention in history, it paved the way for the telephony revolution. Bell was a professor of acoustics and had a passion for sound transmission. With the help of his associate, Thomas Watson, he built a device that converted sound waves into electromagnetic waves, which were transmitted via a cable to a receiver, where they were turned back into sound. Over the years, the invention evolved. Thus, from calls through a manual telephone exchange we moved to automated switchboards, from the rotary dial to touch screens, from corded to portable phones and, finally, to mobile phones and modern digital telecommunications. Today, we cannot imagine our world without this wonderful device that has revolutionised the way we communicate.
6 Euro "150 Jahre seit der Erfindung des Telefons" 2026
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6 Euro "150 Jahre seit der Erfindung des Telefons" 2026
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