|
WLS (AM)
WLS (890 kHz) is a commercial AM broadcasting, AM radio station in Chicago, Illinois. Owned by Cumulus Media, through licensee Radio License Holdings LLC, the station airs a talk radio format. WLS studios are in the NBC Tower on North Columbus Drive in the city's Streeterville neighborhood. The station's programming is also available in the Chicago metropolitan area via a simulcast on the HD2 digital subchannel of sister station WLS-FM. The station formerly broadcast in C-QUAM AM stereo. Its transmitter site is located on the southwestern edge of Tinley Park, Illinois in Will County. WLS is a List of broadcast station classes, Class A station broadcasting on the clear-channel station, clear-channel frequency of 890 kHz with 50,000 watts, using a omnidirectional antenna, non-directional antenna fed by a Nautel NX-50 transmitter, with a Harris DX-50 serving as a backup transmitter. Both transmitters run in MDCL (Modulation Dependent Carrier Level) mode to improve efficiency. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chicago, Illinois
Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of United States cities by population, third-most populous city in the United States after New York City and Los Angeles. As the county seat, seat of Cook County, Illinois, Cook County, the List of the most populous counties in the United States, second-most populous county in the U.S., Chicago is the center of the Chicago metropolitan area, often colloquially called "Chicagoland" and home to 9.6 million residents. Located on the shore of Lake Michigan, Chicago was incorporated as a city in 1837 near a Chicago Portage, portage between the Great Lakes and the Mississippi River, Mississippi River watershed. It grew rapidly in the mid-19th century. In 1871, the Great Chicago Fire destroyed several square miles and left more than 100,000 homeless, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streeterville
Streeterville is a neighborhood in the Near North Side, Chicago, Near North Side community area of Chicago, Illinois, United States, north of the Chicago River. It is bounded by the river on the south, the Magnificent Mile portion of Michigan Avenue (Chicago), Michigan Avenue on the west, and Lake Michigan on the north and east, according to most sources, although the city of Chicago recognizes only a small portion of this region as Streeterville. Thus, it can be described as the Magnificent Mile plus all land east of it. The tourist attraction of Navy Pier and Chicago beaches#Ohio Street Beach, Ohio Street Beach extend out into the lake from southern Streeterville. To the north, the East Lake Shore Drive District, where the Drive curves around the shoreline, may be considered an extension of the Gold Coast (Chicago), Gold Coast. The majority of the land in this neighborhood is reclaimed sandbar. Named for George Streeter, the neighborhood contains a combination of hotels, res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skywave
In radio communication, skywave or skip refers to the propagation of radio waves reflected or refracted back toward Earth from the ionosphere, an electrically charged layer of the upper atmosphere. Since it is not limited by the curvature of the Earth, skywave propagation can be used to communicate beyond the horizon, at intercontinental distances. It is mostly used in the shortwave frequency bands. As a result of skywave propagation, a signal from a distant AM broadcasting station, a shortwave station, or – during sporadic E propagation conditions (principally during the summer months in both hemispheres) – a distant VHF FM or TV station can sometimes be received as clearly as local stations. Most long-distance shortwave ( high frequency) radio communication – between 3 and 30 MHz – is a result of skywave propagation. Since the early 1920s amateur radio operators (or "hams"), limited to lower transmitter power than broadcast statio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Federal Communications Commission
The Federal Communications Commission (FCC) is an independent agency of the United States government that regulates communications by radio, television, wire, internet, wi-fi, satellite, and cable across the United States. The FCC maintains jurisdiction over the areas of broadband access, fair competition, radio frequency use, media responsibility, public safety, and homeland security. The FCC was established pursuant to the Communications Act of 1934 to replace the radio regulation functions of the previous Federal Radio Commission. The FCC took over wire communication regulation from the Interstate Commerce Commission. The FCC's mandated jurisdiction covers the 50 states, the District of Columbia, and the territories of the United States. The FCC also provides varied degrees of cooperation, oversight, and leadership for similar communications bodies in other countries in North America. The FCC is funded entirely by regulatory fees. It has an estimated fiscal-2022 budg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Propagation
Radio propagation is the behavior of radio waves as they travel, or are wave propagation, propagated, from one point to another in vacuum, or into various parts of the atmosphere. As a form of electromagnetic radiation, like light waves, radio waves are affected by the phenomena of reflection (physics), reflection, refraction, diffraction, absorption (electromagnetic radiation), absorption, polarization (waves), polarization, and scattering. Understanding the effects of varying conditions on radio propagation has many practical applications, from choosing frequencies for amateur radio communications, international shortwave Broadcasting, broadcasters, to designing reliable Mobile phone, mobile telephone systems, to radio navigation, to operation of radar systems. Several different types of propagation are used in practical radio transmission systems. ''Line-of-sight propagation'' means radio waves which travel in a straight line from the transmitting antenna to the receiving ante ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmitter
In electronics and telecommunications, a radio transmitter or just transmitter (often abbreviated as XMTR or TX in technical documents) is an electronic device which produces radio waves with an antenna (radio), antenna with the purpose of signal transmission to a radio receiver. The transmitter itself generates a radio frequency alternating current, which is applied to the Antenna (radio), antenna. When excited by this alternating current, the antenna Electromagnetic radiation, radiates radio waves. Transmitters are necessary component parts of all electronic devices that communicate by radio communication, radio, such as radio broadcasting, radio (audio) and television broadcasting stations, cell phones, walkie-talkies, Wireless LAN, wireless computer networks, Bluetooth enabled devices, garage door openers, two-way radios in aircraft, ships, spacecraft, radar sets and navigational beacons. The term ''transmitter'' is usually limited to equipment that generates radio waves fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omnidirectional Antenna
In radio communication, an omnidirectional antenna is a class of antenna (electronics), antenna which radiates equal radio power in all directions perpendicular to an Cartesian coordinate system, axis (azimuthal directions), with power varying with angle to the axis (elevation angle), declining to zero on the axis. When graphed in three dimensions ''(see graph)'' this radiation pattern is often described as ''doughnut-shaped''. This is different from an isotropic radiator, isotropic antenna, which radiates equal power in ''all'' directions, having a ''spherical'' radiation pattern. Omnidirectional antennas oriented vertically are widely used for nondirectional antennas on the surface of the Earth because they radiate equally in all horizontal directions, while the power radiated drops off with elevation angle so little radio energy is aimed into the sky or down toward the earth and wasted. Omnidirectional antennas are widely used for radio broadcasting antennas, and in mobile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clear-channel Station
A clear-channel station is a North American AM radio station that has the highest level of protection from interference from other stations, particularly from nighttime skywave signals. This classification exists to ensure the viability of cross-country or cross-continent radio service enforced through a series of treaties and statutory laws. Known as Class A stations since the 1983 adoption of the Regional Agreement for the Medium Frequency Broadcasting Service in Region 2 (Rio Agreement), they are occasionally still referred to by their former classifications of Class I-A (the highest classification), Class I-B (the next highest class), or Class I-N (for stations in Alaska too far away to cause interference to the primary clear-channel stations in the lower 48 states). The term "clear-channel" is used most often in the context of North America and the Caribbean, where the concept originated. Since 1941, these stations have been required to maintain a transmitter power output ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Broadcast Station Classes
This is a list of broadcast station classes applicable in much of North America under international agreements between the United States, Canada and Mexico. Effective radiated power (ERP) and height above average terrain (HAAT) are listed unless otherwise noted. All radio and television stations within of the US-Canada or US-Mexico border must get approval by both the domestic and foreign agency. These agencies are Industry Canada/ Canadian Radio-television and Telecommunications Commission (CRTC) in Canada, the Federal Communications Commission (FCC) in the US, and the Federal Telecommunications Institute (IFT) in Mexico. AM Station class descriptions All domestic (United States) AM stations are classified as A, B, C, or D. * A (formerly I) — clear-channel stations — 10 kW to 50 kW, 24 hours. **Class A stations are only protected within a radius of the transmitter site. **The old Class I was divided into three: Class I-A, I-B and I-N. NARBA distingu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tinley Park, Illinois
Tinley Park is a village in Cook County, Illinois, Cook and Will County, Illinois, Will counties in the U.S. state of Illinois. The population was 55,971 at the 2020 United States census, 2020 census. It is a suburb in the Chicago metropolitan area. History 19th century Modern settlement of the area now known as Tinley Park began in the 1820s as emigrants from Europe and the eastern United States arrived. By the 1840s, a significant population of German Americans had established themselves in the region. In recognition of their prominence, the village was officially named Bremen when it was founded in 1853. Other early settler groups included Irish Americans, Irish, English Americans, English, Scottish Americans, Scottish, Canadian Americans, Canadian immigrants. In the late 19th century, the Rail transportation in the United States, expansion of the American railroad network had a transformative effect on the area. Bremen was situated along the Chicago, Rock Island and Pacific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AM Stereo
AM stereo is a term given to a series of mutually incompatible techniques for radio broadcasting stereo audio in the AM band in a manner that is compatible with standard AM receivers. There are two main classes of systems: independent sideband (ISB) systems, promoted principally by American broadcast engineer Leonard R. Kahn; and quadrature amplitude modulation (QAM) multiplexing systems (conceptually closer to FM stereo). Initially adopted by many commercial AM broadcasters in the mid to late 1980s, AM stereo broadcasting soon began to decline due to a lack of receivers (most "AM/FM stereo" radios only receive in stereo on FM), a growing exodus of music broadcasters to FM, concentration of ownership of the few remaining stations in the hands of large corporations and the removal of music from AM stations in favor of news/talk or sports broadcasting. By 2001, most of the former AM stereo broadcasters were no longer stereo or had left the AM band entirely. History Early ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C-QUAM
C-QUAM (Compatible QUadrature Amplitude Modulation) is the method of AM stereo broadcasting used in Canada, the United States and most other countries. It was invented in 1977 by Norman Parker, Francis Hilbert, and Yoshio Sakaie, and published in an IEEE journal. Using circuitry developed by Motorola, C-QUAM uses quadrature amplitude modulation (QAM) to encode the stereo separation signal. This extra signal is then stripped down in such a way that it is compatible with the envelope detector of older receivers, hence the name C-QUAM for Compatible. A 25 Hz pilot tone is added to trigger receivers; unlike its counterpart in FM radio, this carrier is not necessary for the reconstruction of the original audio sources. Description The C-QUAM signal is composed of two distinct modulation stages: a conventional AM version and a compatible quadrature PM version. Stage 1 provides the transmitter with a summed L+R mono audio input. This input is precisely the same as conventional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
