Childhood & Early Life
Karl Ferdinand Braun was born on June 6, 1850 in Fulda, Germany to Johan Konrad Braun and Franziska Gohring Braun. He was the fourth child of his parents.
He did his initial education at the local grammar school in Fulda.
After completing high school he studied chemistry and mathematics at the ‘University of Marburg’.
He completed his PhD in physics in 1872 from the ‘University of Berlin’.
Thereafter he worked as a graduate assistant at the Wurzburg University.
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In 1874 Karl Ferdinand Braun discovered that point-contact semiconductors were able to rectify electrical currents from alternating to direct current.
In 1874 he became a member of the teaching faculty at the ‘St. Thomas Gymnasium’ in Leipzig.
He was appointed an ‘Extraordinary Professor of Theoretical Physics’ at the Marburg University in 1877.
He joined the Strasbourg University also as an ‘Extraordinary Professor of Physics’ in 1880.
He joined the ‘Polytechnic School’ in Karlsruhe in 1883 to teach physics.
He was invited to build a new ‘Physics Institute’ by the ‘University of Tubingen’ in 1885.
In 1895 he returned to become a professor of physics at the ‘University of Strasbourg’ and also became the director of the ‘Physical Institute’ at the university.
He built the first Cathode Ray Tube or CRT in 1897 and also the CRT oscilloscope. For almost one century CRTs were used in TV sets and computer monitors until they were replaced by flat-screen LCD screens, LED screens and finally Plasma screens in the 21st century.
He became a member of a group of scientists who were working on the development of wireless and radio technology in 1897.
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He became fully dedicated to solving the problems in wireless telegraphy in 1898 and continued to work on the issue for the next few years.
In 1898 he discovered the ‘cat’s whisker diode’ or crystal rectifier that could transform alternating current to direct current. This helped to increase the distance over which wireless devices could work.
He applied for many patents on his designs related to wireless telegraphy in 1899.
He had started experimenting with wireless telegraphy when he was with the Strasbourg University and was able to connect to the city of Mutzig 42 kilometers away very soon by wireless telegraphy. On September 24, 1900 he was able to set up a wireless telegraphy connection between Cuxhaven in the North Sea coast and the island of Heligoland about 62 kilometers away. Wireless communications between Cuxhaven and light vessels plying on the Elbe River also became possible during this time with his help.
He was instrumental in the execution of the first trans-Atlantic wireless transmission in 1901 which led to the setting up of the wireless telegraphy industry.
In 1902 he was successful in receiving messages with the help of the ‘inclined beam antenna’.
The ‘phased array antenna’ was discovered by him in 1905. This was a combination of three antennas arranged one behind the other for transmitting a directional signal. The radar and the smart antennas were developed later with this technology.
Before the start of the First World War, he was called to the US in 1914 to stand as witness in favor of the wireless station operated by the ‘Atlantic Communication Company’ in Sayville, New York against a law suit filed by the ‘American Marconi Corporation’ which was owned by the British Government.
He could not go back to Germany as the First World War had broken out by then and the US government had joined the war. He was allowed to move about freely inside Brooklyn, New York. He could not carry out any more experiments as he did not have access to any laboratory in New York. He stayed in the house of one of his sons, Konrad till his death.
Personal Life & Legacy
He married Amelie Buhler in 1883 while working at the Polytechnic school in Karlsruhe.
He had two sons and two daughters from this marriage.
Karl Ferdinand Braun died on April 20, 1918 in Brooklyn New York, United States, before the end of the First World War.