While James Clerk Maxwell was the first person to prove electromagnetic waves existed, in 1887 a German named Heinrich Hertz demonstrated these new waves by using spark gap equipment to transmit and receive radio or "Hertzian waves", as they were first called. The experiments were not followed up by Hertz. The practical applications of the wireless communication and remote control technology were implemented by Nikola Tesla.
The world's first radio receiver (thunderstorm register) was designed by Alexander Stepanovich Popov, and it was first seen at the All-Russia Exhibition 1896. He was the first to demonstrate the practical application of electromagnetic (radio) waves,[3] although he did not care to apply for a patent for his invention.
A device called a coherer became the basis for receiving radio signals. The first person to use the device to detect radio waves was a Frenchman named Edouard Branly, and Oliver Lodge popularised it when he gave a lecture in 1898 in honour of Hertz. Lodge also made improvements to the coherer. Many experimenters at the time believed that these new waves could be used to communicate over great distances and made significant improvements to both radio receiving and transmitting apparatus. In 1895 Marconi demonstrated the first viable radio system, leading to transatlantic radio communication in December 1901. The honor was later contested as he was found to be using equipment and designs of other experimenters that held the patents at that time.
John Ambrose Fleming's development of an early thermionic valve to help detect radio waves was based upon a discovery of Thomas Edison's (called "The Edison effect", which essentially modified an early light bulb). Fleming called it his "oscillation valve" because it acted in the same way as water valve in only allowing flow in one direction. While Fleming's valve was a great stride forward it would take some years before thermionic, or vacuum tube technology was fully adopted.
Around this time work on other types of detectors started to be undertaken and it resulted in what was later known as the cat's whisker. It consisted of a crystal of a material such as galena with a small springy piece of wire brought up against it. The detector was constructed so that the wire contact could be moved to different points on the crystal, and thereby obtain the best point for rectifying the signal and the best detection. They were never very reliable as the "whisker" needed to be moved periodically to enable it to detect the signal properly.
The world's first radio receiver (thunderstorm register) was designed by Alexander Stepanovich Popov, and it was first seen at the All-Russia Exhibition 1896. He was the first to demonstrate the practical application of electromagnetic (radio) waves,[3] although he did not care to apply for a patent for his invention.
A device called a coherer became the basis for receiving radio signals. The first person to use the device to detect radio waves was a Frenchman named Edouard Branly, and Oliver Lodge popularised it when he gave a lecture in 1898 in honour of Hertz. Lodge also made improvements to the coherer. Many experimenters at the time believed that these new waves could be used to communicate over great distances and made significant improvements to both radio receiving and transmitting apparatus. In 1895 Marconi demonstrated the first viable radio system, leading to transatlantic radio communication in December 1901. The honor was later contested as he was found to be using equipment and designs of other experimenters that held the patents at that time.
John Ambrose Fleming's development of an early thermionic valve to help detect radio waves was based upon a discovery of Thomas Edison's (called "The Edison effect", which essentially modified an early light bulb). Fleming called it his "oscillation valve" because it acted in the same way as water valve in only allowing flow in one direction. While Fleming's valve was a great stride forward it would take some years before thermionic, or vacuum tube technology was fully adopted.
Around this time work on other types of detectors started to be undertaken and it resulted in what was later known as the cat's whisker. It consisted of a crystal of a material such as galena with a small springy piece of wire brought up against it. The detector was constructed so that the wire contact could be moved to different points on the crystal, and thereby obtain the best point for rectifying the signal and the best detection. They were never very reliable as the "whisker" needed to be moved periodically to enable it to detect the signal properly.
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