A telephone is a communication device that transmits audio signals through wired connections.
Telephone History and Invention
Alexander Graham Bell and Elisha Gray created the telephone in 1876, but only Bell obtained the patent. In 2002, the US Congress admitted Antonio Meucci as the telephone inventor with law number 269.
Antonio Meucci only briefly described his invention in 1871 due to financial difficulties. However, he had to make his patent application more official, as the US Patent Office rejected it.
In 1854, Charles Bourseul suggested using sound vibrations to turn on and off an electrical circuit. He also suggested using those vibrations to recreate the sound in a different place.
Professor Johann Philipp Reis made a machine that could send music through electricity but couldn’t send human voices. It happened a few years later after the first invention.
Antonio Meucci made a phone to connect his rooms. Still, he couldn’t afford to patent it and had to tell another company about it.
Alexander Graham Bell used the materials and features of Meucci’s invention to create his phone.
In 1876, Bell and Gray invented the first telephone that transmitted human voice using direct current. They patented it, and it could send and receive voice messages with a few hours time difference.
Thomas Alva Edison made significant improvements in the carbon granule microphone system of the phone. On June 11, 2002, the US Congress accepted Antonio Meucci as the telephone inventor.
Bell’s patent remained controversial due to rumors suggesting the need to compare the worst or most expensive of the two patents. Bell acknowledged that Gray’s patent could coexist with his own. He also offered an alternative design to Gray’s invention in a note.
Then, in 1876, Bell obtained a patent that did not describe the phone but referred to it that way.
Evolution of the Telephone with Other Technologies
The telephone has improved since it was first invented, including the device and network operation.
The first phone had three parts: a microphone to hear from far away, a device to reduce background noise, and a system for making calls.
Most modern devices use an electret or condenser microphone to improve sound quality. It would help if you had a regular phone that connects to the telephone network to use a phone. This network helps non-portable phones communicate with each other using metal wires.
The initial telephone network used a switchboard operated manually to connect calls. The computer controls electromechanical automatic switching systems.
Fully electronic or computer-controlled digital systems allow many complementary services to establish communications. Broadband systems like ISDN, DSL, ADSL, and HDSL allow faster data transfer.
New phones can send voice and data very quickly.
How does the Telephone Work?
A regular phone has three parts: analog, speech, and dial circuits for calling and dialing. Both audio and dial or search signals and the power supply share the same pair of cables.
The line has a 600Ω impedance and uses two wires to send signals from the phone to the control unit and another control unit on the same line. A hybrid transformer or coil mixes and separates two signals going in opposite directions on the same line.