Portal:Radio

The Radio Portal

Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 Hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves. They can be received by other antennas connected to a radio receiver; this is the fundamental principle of radio communication. In addition to communication, radio is used for radar, radio navigation, remote control, remote sensing, and other applications.

In radio communication, used in radio and television broadcasting, cell phones, two-way radios, wireless networking, and satellite communication, among numerous other uses, radio waves are used to carry information across space from a transmitter to a receiver, by modulating the radio signal (impressing an information signal on the radio wave by varying some aspect of the wave) in the transmitter. In radar, used to locate and track objects like aircraft, ships, spacecraft and missiles, a beam of radio waves emitted by a radar transmitter reflects off the target object, and the reflected waves reveal the object's location to a receiver that is typically colocated with the transmitter. In radio navigation systems such as GPS and VOR, a mobile navigation instrument receives radio signals from multiple navigational radio beacons whose position is known, and by precisely measuring the arrival time of the radio waves the receiver can calculate its position on Earth. In wireless radio remote control devices like drones, garage door openers, and keyless entry systems, radio signals transmitted from a controller device control the actions of a remote device. (Full article...)

Selected article -

Dee in 1951

Mary Dudley (born Mary Elizabeth Goode; April 8, 1912 – March 17, 1964), known as Mary Dee, was an American disc jockey who is widely considered the first African-American woman disc jockey in the United States. She grew up in Homestead, Pennsylvania, and then studied at Howard University for two years. After having her family, she attended Si Mann School of Radio in Pittsburgh, and on August 1, 1948, went on the air at WHOD radio. Gaining national attention, Dee broadcast from a storefront, "Studio Dee", in the Hill District of Pittsburgh from 1951 to 1956. She moved her show, Movin' Around with Mary Dee, to Baltimore and broadcast from station WSID from 1956 to 1958. In 1958, she moved to Philadelphia and hosted Songs of Faith on WHAT until her death in 1964.

Dee is considered a pioneer in developing the radio format that combines coverage of community affairs with music and news. She was one of the first two black women admitted to the Association of American Women in Radio and Television, and was successful in campaigning for the organization to forgo meetings in segregated facilities. During her lifetime she received numerous awards for her civic work. In 2011 she was honored posthumously with the Thomas J. MacWilliams Lifetime Achievement Award from the Media Association of Pittsburgh. (Full article...)

List of selected articles

General images -

The following are images from various radio-related articles on Wikipedia.

Image 1Oliver Lodge's 1894 lectures on Hertz demonstrated how to transmit and detect radio waves. (from History of radio)
Image 2Heinrich Rudolf Hertz (1856–1894) proved the existence of electromagnetic radiation. (from History of radio)
Image 3Early experiment demonstrating refraction of microwaves by a paraffin lens by John Ambrose Fleming in 1897 (from History of radio)
Image 4In the 1920s, the United States government publication, "Construction and Operation of a Simple Homemade Radio Receiving Outfit", showed how almost any person handy with simple tools could a build an effective crystal radio receiver. (from History of radio)
Image 5Wildlife officer tracking radio-tagged mountain lion (from Radio)
Image 6Around 1920, radio broadcasting started to get popular. The Brox Sisters, a popular singing group, gathered around the radio at the time. (from History of radio)
Image 7A laptop (with Wi-Fi module) and a typical home wireless router (on the right) connecting it to the Internet. The laptop shows its own photo (from Radio)
Image 8Donald Manson working as an employee of the Marconi Company (England, 1906) (from History of radio)
Image 9Animation of a half-wave dipole antenna radiating radio waves, showing the electric field lines. The antenna in the center is two vertical metal rods connected to a radio transmitter (not shown). The transmitter applies an alternating electric current to the rods, which charges them alternately positive (+) and negative (−). Loops of electric field leave the antenna and travel away at the speed of light; these are the radio waves. In this animation the action is shown slowed down tremendously. (from Radio wave)
Image 10Neighborhood wireless WAN router on telephone pole (from Radio)
Image 11The first commercial AM Audion vacuum tube radio transmitter, built in 1914 by Lee De Forest who invented the Audion (triode) in 1906 (from History of radio)
Image 12British Post Office engineers inspect Guglielmo Marconi's wireless telegraphy (radio) equipment in 1897. (from History of radio)
Image 13An antenna farm hosting various radio antennas on Sandia Peak near Albuquerque, New Mexico, United States (from Radio)
Image 14Early pioneers of radio science and technology in the United States including Charles Steinmetz, David Sarnoff, Irving Langmuir and Alfred Goldsmith in 1921, photographed next to the antenna feed wires of the New Brunswick Marconi Station, one of the first transatlantic radio links. Photo includes Albert Einstein as a visiting guest. (from History of radio)
Image 15Radio waves symbol (from Radio wave)
Image 16Advertisement placed on November 5, 1919 in the Nieuwe Rotterdamsche Courant, announcing PCGG's debut broadcast scheduled for the next evening. (from Radio broadcasting)
Image 17Localizer antenna array at Heathrow Airport, London (from Radio)
Image 18Control room and radio studio of the Finnish broadcasting company Yleisradio (YLE) in the 1930s. (from Radio broadcasting)
Image 19An early iPhone with its GPS navigation app in use. (from Radio)
Image 20Reginald Fessenden (around 1906) (from History of radio)
Image 21Radio communication. Information such as sound is converted by a transducer such as a microphone to an electrical signal, which modulates a radio wave produced by the transmitter. A receiver intercepts the radio wave and extracts the information-bearing modulation signal, which is converted back to a human usable form with another transducer such as a loudspeaker. (from Radio)
Image 22Comparison of AM and FM modulated radio waves (from Radio)
Image 23Diagram of the electric fields (E) and magnetic fields (H) of radio waves emitted by a monopole radio transmitting antenna (small dark vertical line in the center). The E and H fields are perpendicular, as implied by the phase diagram in the lower right. (from Radio wave)
Image 24Use of a sound broadcasting station (from Radio broadcasting)
Image 25Animated diagram of a half-wave dipole antenna receiving a radio wave. The antenna consists of two metal rods connected to a receiver $R$ . The electric field ( $E$ , green arrows) of the incoming wave results in oscillation of the electrons in the rods, charging the ends alternately positive (+) and negative (−). Since the length of the antenna is one half the wavelength of the wave, the oscillating field induces standing waves of voltage ( $V$ , represented by red band) and current in the rods. The oscillating currents (black arrows) flow down the transmission line and through the receiver (represented by the resistance $R$ ). (from Radio wave)
Image 26Rotating marine radar antenna on a ship (from Radio)
Image 27Volkswagen's RNS-510 receiver supports Sirius Satellite Radio. (from Radio)
Image 28Worldwide presence of Radio Maria broadcasters (from Radio broadcasting)
Image 29The Regency TR-1, which used Texas Instruments' NPN transistors, was the world's first commercially produced transistor radio in 1954. Size: 3×5×1.25 inch (7.6×12.7×3.2 cm) (from History of radio)
Image 30Frequency spectrum of a typical modulated AM or FM radio signal. It consists of a component C at the carrier wave frequency $f_{c}$ with the modulated information contained in two narrow bands of frequencies called sidebands (SB) just above and below the carrier frequency. The bandwidth (BW) is the amount of spectrum occupied by the sidebands. (from Radio)

List articles

105.9 FM
97.3 FM
FM broadcasting in Egypt
High school radio
List of BBC Radio 4 programmes
List of Dad's Army radio episodes
List of fictional radio stations
List of indie radio stations
List of old-time American radio people
List of old-time radio programs
List of radios – List of specific models of radios
Lists of radio stations (category page)
List of Sirius Satellite Radio stations
List of the world's oldest radio stations
List of This American Life episodes
List of U.S. radio programs
List of UK radio programmes
List of XM Satellite Radio channels
Q107
Q92
Radio Stations of the BBC
Reith Lecture
Z103

Did you know...

... that Anna DeShawn started E3 Radio to help educate others about Black women that she did not learn about in grade school?
... that technical issues in the minute before their November 2024 BBC Radio 1 performance meant that South Arcade had to set up while the presenter was announcing them?
... that the Upper Voltan National Radio chief editor Watamou Lamien was the liaison between the ROC group of young radical military officers and the clandestine Voltan Revolutionary Communist Party?
... that the satellite TRUTHS is planned to enable the precise calibration of Earth observation data from other satellites?
... that the Armenian Radio jokes are neither about radio nor are they Armenian?
... that Shanthi Kalathil believes Radio Free Asia "filled a critical role in combating Chinese disinformation"?

Selected quote -

“

You see, wire telegraph is a kind of a very, very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? And radio operates exactly the same way: you send signals here, they receive them there. The only difference is that there is no cat.

”

— Albert Einstein - when asked to describe radio

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Radio

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Radio astronomy

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History of radio

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Radio theme songs

Trunked radio systems

Types of radios

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Radio websites

Radio stubs

Radio topics

Formats	Community radio, Music radio, Old-time radio, Radio comedy, Radio documentary, Radio drama, Sports radio, Talk Radio, Top 40
Networks	BBC Radio, Blue Network, Columbia Broadcasting System, Mutual Broadcasting System, National Broadcasting Company, Sirius Satellite Radio, XM Satellite Radio
People	Fred Allen, Gracie Allen, Don Ameche, Jack Benny, Edgar Bergen, Jagadish Chandra Bose, George Burns, Charlamagne tha God, Ronald Colman, Jim Connors, Frank Conrad, Norman Corwin, Charles Coughlin, Frankie Crocker, Ebro Darden, Alice Faye, Stan Freberg, Sean Hannity, Vaughn Harper, Phil Harris, Bob Hope, Hal Jackson, Spike Jones, Tom Joyner, Hans von Kaltenborn, Larry Elder, Larry King, Kay Kyser, Frances Langford, Rush Limbaugh, Guglielmo Marconi, Angie Martinez, Elizabeth McLeod, J. Carrol Naish, Ozzie Nelson, Arch Oboler, Dorothy Parker, Virginia Payne, Harold Peary, David Sarnoff, Red Skelton, Kate Smith, Stephen A. Smith, Howard Stern, Nikola Tesla, Jonathan Toubin, Lurene Tuttle, Rudy Vallée, Fred Waring, Orson Welles, Wendy Williams, Angela Yee
Shows	Abbott and Costello, Amos 'n' Andy, Arch Oboler's Plays, The Breakfast Club, Burns and Allen, Cavalcade of America, CBS Radio Mystery Theater, Dragnet, Duffy's Tavern, Ebro in the Morning, Fibber McGee and Molly, The Goldbergs, The Howard Stern Show, Inner Sanctum Mysteries, The Jack Benny Program, Life with Luigi, Lights Out, Lux Radio Theater, Opie and Anthony, The Archers, The Hitchhiker's Guide to the Galaxy, The Phil Harris-Alice Faye Show, Quiz Kids, The Screen Guild Theater, The Shadow, Suspense, Theater Guild on the Air, Twenty Questions, The Whistler, Yours Truly, Johnny Dollar, Tom Joyner Morning Show, Rush Limbaugh Show
Technology	Amateur radio, AM broadcasting, FM broadcasting, International broadcasting, Internet Radio, Digital Radio Mondiale, HD Radio, Digital Audio Broadcasting, GNU Radio, Software-defined radio, Transistor radio, Vacuum tube, Pirate radio Top 40
Industry	Radio promotion

WikiProjects

Radio December 12, 2006 "...to create, expand, and maintain Wikipedia articles related to radio, including radio propagation and reception, radio programming, radio personalities, and the business of radio." (Example: Mutual Broadcasting System)
Radio Stations February 15, 2005 "...to coordinate the activities of creating and maintaining articles about radio stations." (Example: Pulse FM Kingborough & Huon)
Podcasting January 21, 2007 "...to make Wikipedia's knowledge of notable Podcast and podcast-related information as complete as possible." (Example: Podcast)
Amateur Radio (Inactive), August 24, 2006 "...to improve Wikipedia's articles related to Amateur radio, maintain the amateur radio category and its sub-categories for clean organization, and to produce and maintain templates for Amateur radio-related topic identification." (Example: Amateur radio)

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