2025年1月13日 · This article describes the functional components of the modern telephone and traces the historical development of the telephone instrument. In addition it describes the development of what is known as the public switched telephone network (PSTN).

The first telephone had two parts: a transmitter and a receiver. The transmitter comprised three parts—a drumlike device (a cylinder with a covered end), a needle, and a battery. The covered end of the drumlike device was attached to the needle.

The base receives the call as an electric signal, like a corded phone does. Then the base turns the electric signal into radio waves. Using an antenna, the base sends the waves through the air to the handset.

2025年1月13日 · Telephone - Network, Communication, Technology: In order to understand the many concepts represented in the public switched telephone network (PSTN), it is helpful to review the processes that take place in the making of …

2025年1月13日 · Telephone - Transmission, Signals, Networks: The first telephone lines employed the same type of outdoor circuits as telegraph lines—namely, a single noninsulated iron or steel wire supported by wooden poles with glass insulators.

telephone, Instrument designed for simultaneous transmission and reception of the human voice. It works by converting the sound waves of the human voice to pulses of electric current, transmitting the current, and then retranslating the current back to sound.

In March 1876, Bell and his assistant Thomas Watson held the first telephone call in history. On his 29th birthday, Bell achieved his lifelong dream. He received the hotly contested patent for a technology that remains an indispensable part of our lives to this day.

2025年1月13日 · Telephone - Overseas Transmission: The extension of telephone service to other countries and continents was a goal set in the earliest days of telephone systems. In North America, service to Canada and Mexico was a natural extension of the long-distance methods used within the United States, but transmission across the ocean to Europe called ...

2024年12月21日 · How did Alexander Graham Bell’s telephone work? The first telephone had two parts: a transmitter and a receiver. The transmitter comprised three parts—a drumlike device (a cylinder with a covered end), a needle, and a battery .

2025年1月13日 · Telephone - Invention, Alexander Graham Bell, Communication: Beginning in the early 19th century, several inventors made a number of attempts to transmit sound by electric means. The first inventor to suggest that sound could be transmitted electrically was a Frenchman, Charles Bourseul, who indicated that a diaphragm making and breaking ...