HIMCOM-Heritage Institute of Management & Communication

                                                Mechanical By the 1920s, when amplification made television practical, Scottish inventor John Logie Baird employed the Nipkow disk in his prototype video systems. On 25 March 1925, Baird gave the first public demonstration of televised silhouette images in motion, at Selfridge’s Department Store in London.Since human faces had inadequate contrast to show up on his primitive system, he televised a ventriloquist's dummy named "Stooky Bill", whose painted face had higher contrast, talking and moving. By 26 January 1926, he demonstrated the transmission of the image of a face in motion by radio. This is widely regarded as the first television demonstration. The subject was Baird's business partner Oliver Hutchinson. Baird's system used the Nipkow disk for both scanning the image and displa...

                                                  Mechanical Facsimile transmission systems for still photographs pioneered methods of mechanical scanning of images in the early 19th century. Alexander Bain introduced the facsimile machine between 1843 and 1846. Frederick Bakewell demonstrated a working laboratory version in 1851. Willough by Smith discovered the photoconductivity of the element selenium in 1873. As a 23-year-old German university student, Paul Jukius Gottlieb Nipkow proposed and patented the Nipkow disk in 1884. This was a spinning disk with a spiral pattern of holes in it, so each hole scanned a line of the image. Although he never built a working model of the system, variations of Nipkow's spinning-disk "image rasterizer " became exceedingly common. Constantin Perskyi had coined the word  tel...

                                                                               History The invention of the television was the work of many individuals in the late 19th century and early 20th century. Individuals and corporations competed in various parts of the world to deliver a device that superseded previous technology. Many were compelled to capitalize on the invention and make profit, while some wanted to change the world through visual and audio communication technology. [1] The first mechanical raster scanning techniques were developed in the 19th century for facsimile, the transmission of still images by wire. Alexander Bain introduced the facsimile machine in 1843 to 1846. Frederick Bakewell demonstrated a working laboratory version in 1851....

                                                                                   Digital television Digital television  ( DTV ) is the transmission of television signals, including the sound channel, using digital encoding, in contrast to the earlier television technology, analog television, in which the video and audio are carried by analog singnals. It is an innovative advance that represents the first significant evolution in television technology since color television in the 1950s. Digital TV transmits in a new image format called high definition television (HDTV), with greater resolution than analog TV, in a widescreen aspect ratio similar to recent movies in contrast to the narrower screen of analog TV. It mak...

                                                                                      Etymology The word  television  comes from Ancient Greek τῆλε  (tèle) , meaning 'far', and Latin  visio , meaning 'sight'. The first documented usage of the term dates back to 1900, when the Russian scientist Constantin Perskyi used it in a paper that he presented in French at the 1st International Congress of Electricity, which ran from 18 to 25 August 1900 during the International World Fair in Paris. The Anglicised version of the term is first attested in 1907, when it was still "...a theoretical system to transmit moving images over telegrapgh  or telephone wires". It was "...formed in English or borrowed from Fre...

                                                                                                                                       Television Television  ( TV ), sometimes shortened to  tele  or  telly , is a telecommunication medium used for transmitting moving images in  monochrome (black and white), or in color, and in two or  three dimensions and sound. The term can refer to a television set, a television program ("TV show"), or the medium of television transmission. Television is a mass medium for advertisi...

                                                                                    Radio and television Starting in 1894, Italian inventor Guglielmo Marconi began developing a wireless communication using the then newly discovered phenomenon of radio waves, showing by 1901 that they could be transmitted across the Atlantic Ocean. This was the start of wireless telegraphy by radio. Voice and music were demonstrated in 1900 and 1906, but had little early success. World War accelerated the development of radio for military communication. After the war, commercial radio AM broadcasting  began in the 1920s and became an important mass medium for entertainment and news. World War II again accelerated development of radio...

                                        Telecommunication Telecommunication is the  transmission of signs, signals, messages, words, writings, images and sounds or information of any nature by wire, radio, optical or   other electromagnetic systems. Telecommunication occurs when the exchange of information between communication participants includes the use of technology. It is transmitted through a transmission media, such as over physical media, for example, over electrical cable, or via electromagnetic through space such as radio or light. Such transmission paths are often divided into communication channels which afford the advantages of multiplexing. Since the Latin term  communication  is considered th...

                                                      Etymology The word "radio" is derived from the Latin word "radius", meaning "spoke of a wheel, beam of light, ray". It was first applied to communications in 1881 when, at the suggestion of French scientist Ernest Mercadier,  Alexander Graham Bell  adopted "radiophone" (meaning "radiated sound") as an alternate name for his photo phone optical transmission system.   However, this invention would not be widely adopted. Following Heinrich Hertz’s discovery of the existence of radio waves in 1886, a variety of terms were initially used for this radiation, including "Hertzian waves", "electric waves", and "ether waves". The first practical radio communications systems, developed by Guglielmo Marconi in 1894-5, transmitted telegraph signals by radio waves, ...

                                                                                         Scientific research Radio astronomy  is a subfield of astronomy that studies celestial objects at radio frequencies. The first detection of radio waves from an astronomical object was in 1932, when Karl Jansky at Bell Telephone Laboratories observed radiation coming from the Milky Way. Subsequent observations have identified a number of different sources of radio emission. These include stars and galaxies, as well as entirely new classes of objects, such as radio galaxies, quasars, pulsars and masers.The discovery of the cosmic microwave background radiation, regarded as evidence for the Big Bang theory, was made through rad...