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.
147-975: All radio and television stations within 320 kilometers (199 miles) 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. All domestic (United States) AM stations are classified as A , B , C , or D . Notes: AM station classes were previously assigned Roman numerals from I to IV in
294-489: A charter for a new colony to the Virginia Company of London . The group financed an expedition under Christopher Newport that established a settlement named Jamestown in 1607. Though more settlers soon joined, many were ill-prepared for the dangers of the new settlement. As the colony's president, John Smith secured food for the colonists from nearby tribes, but after he left in 1609, this trade stopped and
441-663: A group of Spanish Jesuits , explored the Chesapeake Bay during the 16th century. To help counter Spain's colonies in the Caribbean , Queen Elizabeth I of England supported Walter Raleigh 's 1584 expedition to the Atlantic coast of North America . The name "Virginia" was used by Captain Arthur Barlowe in the expedition's report, and may have been suggested by Raleigh or Elizabeth (perhaps noting her status as
588-593: A racially segregated society , and in 1902 rewrote the state constitution to include a poll tax and other voter registration measures that effectively disenfranchised most African Americans and many poor whites. New economic forces meanwhile industrialized the Commonwealth. Virginian James Albert Bonsack invented the tobacco cigarette rolling machine in 1880 leading to new large-scale production centered around Richmond. Railroad magnate Collis Potter Huntington founded Newport News Shipbuilding in 1886, which
735-425: A raid on Harpers Ferry, Virginia , in an attempt to start a slave revolt across the southern states. The polarized national response to his raid, capture, trial, and execution that December marked a tipping point for many who believed slavery would need to be ended by force. Abraham Lincoln 's 1860 election further convinced many southern supporters of slavery that his opposition to its expansion would ultimately mean
882-402: A series of ambush-style killings between colonists and natives under Chief Powhatan and his brother began, resulting in mass starvation in the colony that winter. By the end of the colony's first fourteen years, over eighty percent of the roughly eight thousand settlers transported there had died. Demand for exported tobacco , however, fueled the need for more workers. Starting in 1618,
1029-427: A "radio station" as a government-licensed AM or FM station; an HD Radio (primary or multicast) station; an internet stream of an existing government-licensed station; one of the satellite radio channels from XM Satellite Radio or Sirius Satellite Radio ; or, potentially, a station that is not government licensed. AM stations were the earliest broadcasting stations to be developed. AM refers to amplitude modulation ,
1176-530: A 50,000 watt maximum for the US and Canada, but no maximum for other governments in the region. Mexico, for example, typically runs 150,000 to 500,000 watts, but some stations are grandfathered at 10,000 to 20,000 watts at night; by treaty, these sub-50,000 watt Mexican stations may operate with a maximum of 100,000 watts during the daytime. Because the AM broadcast band developed before technology suitable for directional antennas , there are numerous exceptions, such as
1323-722: A bloody Confederate victory. Union General George B. McClellan organized the Army of the Potomac , which landed on the Virginia Peninsula in March 1862 and reached the outskirts of Richmond that June. With Confederate General Joseph E. Johnston wounded in fighting outside the city, command of his Army of Northern Virginia fell to Robert E. Lee . Over the next month, Lee drove the Union army back , and starting that September led
1470-494: A business opportunity to sell advertising or subscriptions to a broader audience. This is more efficient than broadcasting to a single country, because domestic entertainment programs and information gathered by domestic news staff can be cheaply repackaged for non-domestic audiences. Governments typically have different motivations for funding international broadcasting. One clear reason is for ideological, or propaganda reasons. Many government-owned stations portray their nation in
1617-439: A century, at a magnitude of 5.8, struck central Virginia on August 23, 2011 . 35 million years ago, a bolide impacted what is now eastern Virginia. The resulting Chesapeake Bay impact crater may explain what earthquakes and subsidence the region does experience. A meteor impact is also theorized as the source of Lake Drummond , the largest of the two natural lakes in the state . The Commonwealth's carbonate rock
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#17327804258401764-460: A few Class B stations with grandfathered power limits in excess of 50 KW, such as WETA (licensed for Washington DC in zone I, at a power of 75 kW ERP), WNCI ( Columbus, Ohio in zone I, at 175 kW ERP), KPFK (Los Angeles in zone I-A, at 110 KW ERP), and the most extreme example being WBCT ( Grand Rapids, Michigan , in zone I, at 320 kW ERP). Notes: All full-power analog television station transmissions in
1911-539: A governor who ignored the assembly and sent him back to England against his will. William Berkeley was named governor in 1642, just as the turmoil of the English Civil War and Interregnum permitted the colony greater autonomy. As a supporter of the king, Berkeley welcomed other Cavaliers who fled to Virginia. He surrendered to Parliamentarians in 1652, but after the 1660 Restoration made him governor again, he blocked assembly elections and exacerbated
2058-463: A kind of vacuum tube , was invented in 1904 by the English physicist John Ambrose Fleming . He developed a device that he called an "oscillation valve," because it passes current in only one direction. The heated filament, or cathode , was capable of thermionic emission of electrons that would flow to the plate (or anode ) when it was at a higher voltage. Electrons, however, could not pass in
2205-618: A major urban business and shopping center in Tysons , Virginia's largest office market. Neighboring Prince William County , with over 450,000 residents, is Virginia's second-most populous county and home to Marine Corps Base Quantico , the FBI Academy , and Manassas National Battlefield Park . Arlington County is the smallest self-governing county in the U.S. by land area, and local politicians have proposed reorganizing it as an independent city due to its high density. Loudoun County
2352-546: A mode of broadcasting radio waves by varying the amplitude of the carrier signal in response to the amplitude of the signal to be transmitted. The medium-wave band is used worldwide for AM broadcasting. Europe also uses the long wave band. In response to the growing popularity of FM stereo radio stations in the late 1980s and early 1990s, some North American stations began broadcasting in AM stereo , though this never gained popularity and very few receivers were ever sold. The signal
2499-592: A national boundary. In other cases, a broadcast may be considered "pirate" due to the type of content, its transmission format, or the transmitting power (wattage) of the station, even if the transmission is not technically illegal (such as a webcast or an amateur radio transmission). Pirate radio stations are sometimes referred to as bootleg radio or clandestine stations. Digital radio broadcasting has emerged, first in Europe (the UK in 1995 and Germany in 1999), and later in
2646-437: A national park, but is protected by both state and federal legislation and the inter-state Chesapeake Bay Program . Virginia is divided into 95 counties and 38 independent cities , which the U.S. Census Bureau describes as county-equivalents . This general method of treating cities and counties on par with each other is unique to Virginia and stretches back to the influence of Williamsburg and Norfolk in
2793-426: A positive, non-threatening way. This could be to encourage business investment in or tourism to the nation. Another reason is to combat a negative image produced by other nations or internal dissidents, or insurgents. Radio RSA , the broadcasting arm of the apartheid South African government, is an example of this. A third reason is to promote the ideology of the broadcaster. For example, a program on Radio Moscow from
2940-533: A public audience . In terrestrial radio broadcasting the radio waves are broadcast by a land-based radio station , while in satellite radio the radio waves are broadcast by a satellite in Earth orbit. To receive the content the listener must have a broadcast radio receiver ( radio ). Stations are often affiliated with a radio network that provides content in a common radio format , either in broadcast syndication or simulcast , or both. The encoding of
3087-634: A radio broadcast depends on whether it uses an analog or digital signal . Analog radio broadcasts use one of two types of radio wave modulation : amplitude modulation for AM radio , or frequency modulation for FM radio . Newer, digital radio stations transmit in several different digital audio standards, such as DAB ( Digital Audio Broadcasting ), HD radio , or DRM ( Digital Radio Mondiale ). The earliest radio stations were radiotelegraphy systems and did not carry audio. For audio broadcasts to be possible, electronic detection and amplification devices had to be incorporated. The thermionic valve ,
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#17327804258403234-642: A referendum and went into effect in 1971. In 1989, Douglas Wilder became the first African American elected as governor in the United States, and in 1992, Bobby Scott became the first Black congressman from Virginia since 1888. The expansion of federal government offices into Northern Virginia's suburbs during the Cold War boosted the region's population and economy. The Central Intelligence Agency outgrew their offices in Foggy Bottom during
3381-412: A significant threat to the AM broadcasting industry. It required purchase of a special receiver. The frequencies used, 42 to 50 MHz, were not those used today. The change to the current frequencies, 88 to 108 MHz, began after the end of World War II and was to some extent imposed by AM broadcasters as an attempt to cripple what was by now realized to be a potentially serious threat. FM radio on
3528-498: A station of this type shares the callsign of another station. In analog, these services often were broadcast on the same or adjacent channels to their parent station, except in certain areas with tight packing of television stations (such as central Mexico). In digital, these services usually operate on the same RF channel as their parent station, except for those with conflicting full-power applications ( XHBS-TDT Cd. Obregón, Son., channel 30 instead of 25), in certain other cases where it
3675-943: A strategy called " massive resistance ", and the General Assembly passed a package of laws in 1956 that cut off funding to local schools that desegregated , causing some to close. Courts ruled the strategy unconstitutional, and on February 2, 1959, Black students integrated schools in Arlington and Norfolk , where they were known as the Norfolk 17 . County leaders in Prince Edward, however, instead shut their school system in June 1959. The Supreme Court ordered them to reopen and integrate their public schools , which finally happened in September 1964. Federal passage of
3822-619: A strong effect on eastern and southeastern coastal areas, making the climate there warmer but also more constant. Most of Virginia's recorded extremes in temperature and precipitation have occurred in the Blue Ridge Mountains and areas west. Virginia receives an average of 43.47 inches (110 cm) of precipitation annually, with the Shenandoah Valley being the state's driest region. Virginia has around 35–45 days with thunderstorms annually, and storms are common in
3969-571: A total population of around 15,000 in 1607. Three-fourths of the native population in Virginia, however, died from smallpox and other Old World diseases during that century, disrupting their oral traditions and complicating research into earlier periods. Additionally, many primary sources, including those that mention Powhatan's daughter, Pocahontas , were created by Europeans, who may have held biases or misunderstood native social structures and customs. Several European expeditions, including
4116-604: Is Richmond and its most populous city is Virginia Beach . Its most populous subdivision is Fairfax County , part of Northern Virginia , where slightly over a third of Virginia's population of 8.7 million live. Eastern Virginia is part of the Atlantic Plain , and the Middle Peninsula forms the mouth of the Chesapeake Bay . Central Virginia lies predominantly in the Piedmont , the foothill region of
4263-426: Is all that is necessary for a narrowband FM signal. The 200 kHz bandwidth allowed room for ±75 kHz signal deviation from the assigned frequency, plus guard bands to reduce or eliminate adjacent channel interference. The larger bandwidth allows for broadcasting a 15 kHz bandwidth audio signal plus a 38 kHz stereo "subcarrier" —a piggyback signal that rides on the main signal. Additional unused capacity
4410-616: Is called the Shenandoah Valley in Virginia, named after the river of the same name that flows through it. The Cumberland Plateau and Cumberland Mountains are in the southwest corner of Virginia, south of the Allegheny Plateau . In this region, rivers flow northwest into the Ohio River basin. The Virginia Seismic Zone has not had a history of regular earthquake activity. Earthquakes are rarely above 4.5 in magnitude . The Commonwealth's largest earthquake in at least
4557-469: Is divided into three zones for FM broadcasting: I, I-A and II. The zone where a station is located may limit the choices of broadcast class available to a given FM station. Zone I in the US includes all of Connecticut , the District of Columbia , Delaware , Illinois , Indiana , Massachusetts , Maryland , New Jersey , Ohio , Pennsylvania , Rhode Island , and West Virginia . It also includes
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4704-480: Is filled with more than 4,000 limestone caves , ten of which are open for tourism, including the popular Luray Caverns and Skyline Caverns . Virginia's iconic Natural Bridge is the remaining roof of a collapsed limestone cave. Coal mining takes place in the three mountainous regions. More than 72 million tons of other non-fuel resources, such as slate , kyanite , sand, or gravel, were mined in Virginia in 2020 . The largest known deposits of uranium in
4851-447: Is licensed for two watts in digital. The highest-powered shadows are XEQ-TDT Toluca and XHBS-TDT Ciudad Obregón, both at 200 kW. The United States Federal Communications Commission lists the following services on their website for television broadcasting: Radio station Radio broadcasting is the broadcasting of audio (sound), sometimes with related metadata , by radio waves to radio receivers belonging to
4998-421: Is little affected by daily changes in the ionosphere, so broadcasters need not reduce power at night to avoid interference with other transmitters. FM refers to frequency modulation , and occurs on VHF airwaves in the frequency range of 88 to 108 MHz everywhere except Japan and Russia . Russia, like the former Soviet Union , uses 65.9 to 74 MHz frequencies in addition to the world standard. Japan uses
5145-472: Is sometimes mandatory, such as in New Zealand, which uses 700 kHz spacing (previously 800 kHz). The improved fidelity made available was far in advance of the audio equipment of the 1940s, but wide interchannel spacing was chosen to take advantage of the noise-suppressing feature of wideband FM. Bandwidth of 200 kHz is not needed to accommodate an audio signal — 20 kHz to 30 kHz
5292-552: Is still considered LPTV with respect to stations in Canada and Mexico. Class-A stations (US) (suffix: -CA or -CD for digital class A): The class-A television class is a variant of LPTV created in 2000 by the FCC to allocate and protect some low-power affiliates. Class-A stations are still low-power, but are protected from RF interference and from having to change channel should a full-service station request that channel. Additionally, class-A stations, LPTV stations, and translators are
5439-453: Is subject to interference from electrical storms ( lightning ) and other electromagnetic interference (EMI). One advantage of AM radio signal is that it can be detected (turned into sound) with simple equipment. If a signal is strong enough, not even a power source is needed; building an unpowered crystal radio receiver was a common childhood project in the early decades of AM broadcasting. AM broadcasts occur on North American airwaves in
5586-516: Is technically not feasible ( XHAW-TDT Guadalupe, NL, channel 26 instead of 25) or to make way for eventual repacking on upper UHF ( XHPNW-TDT has four shadows on 33, its post-repacking channel, instead of 39). Equipos complementarios can relay their parent station, or a station that carries 75% or more of the same programming as its parent station. Stations of either type may have unusually low or high effective radiated powers. XHSMI-TDT in Oaxaca
5733-735: Is the automation of radio stations. Some stations now operate without direct human intervention by using entirely pre-recorded material sequenced by computer control. Virginia Virginia , officially the Commonwealth of Virginia , is a state in the Southeastern and Mid-Atlantic regions of the United States between the Atlantic Coast and the Appalachian Mountains . The state's capital
5880-545: Is the fastest-growing county in the state. In western Virginia, Roanoke city and Montgomery County , part of the Blacksburg–Christiansburg metropolitan area , both have surpassed a population of 100,000 since 2018. On the western edge of the Tidewater region is Virginia's capital, Richmond , which has a population of around 230,000 in its city proper and over 1.3 million in its metropolitan area. On
6027-447: Is used by some broadcasters to transmit utility functions such as background music for public areas, GPS auxiliary signals, or financial market data. The AM radio problem of interference at night was addressed in a different way. At the time FM was set up, the available frequencies were far higher in the spectrum than those used for AM radio - by a factor of approximately 100. Using these frequencies meant that even at far higher power,
List of North American broadcast station classes - Misplaced Pages Continue
6174-829: The American Revolution , and helped establish the new national government. During the American Civil War , the state government in Richmond joined the Confederacy , while many northwestern counties remained loyal to the Union , which led to the separation of West Virginia in 1863. Although the state was under one-party rule for nearly a century following the Reconstruction era , both major political parties have been competitive in Virginia since
6321-647: The Back Bay National Wildlife Refuge , which marks the beginning of the Outer Banks . State agencies control about one-third of protected land in the state, and the Virginia Department of Conservation and Recreation manages over 75,900 acres (307.2 km ) in forty Virginia state parks and 59,222 acres (239.7 km ) in 65 Natural Area Preserves , plus three undeveloped parks. Breaks Interstate Park crosses
6468-631: The Blue Ridge Mountains , which cross the western and southwestern parts of the state. The fertile Shenandoah Valley fosters the state's most productive agricultural counties, while the economy in Northern Virginia is driven by technology companies and U.S. federal government agencies. Hampton Roads is also the site of the region's main seaport and Naval Station Norfolk , the world's largest naval base. Virginia's history begins with several Indigenous groups , including
6615-699: The Civil Rights Act (1964) and Voting Rights Act (1965), and their later enforcement by the Justice Department , helped end racial segregation in Virginia and overturn Jim Crow laws . In 1967, the Supreme Court struck down the state's ban on interracial marriage with Loving v. Virginia . In 1968, Governor Mills Godwin called a commission to rewrite the state constitution. The new constitution, which banned discrimination and removed articles that now violated federal law, passed in
6762-560: The Committee of Nine . During the post-war Reconstruction era , African Americans were able to unite in communities, particularly around Richmond , Danville , and the Tidewater region , and take a greater role in Virginia society; many achieved some land ownership during the 1870s. Virginia adopted a constitution in 1868 which guaranteed political, civil, and voting rights , and provided for free public schools. However, with many railroad lines and other infrastructure destroyed during
6909-862: The Korean War , and moved to Langley in 1961, in part due to a decision by the National Security Council that the agency relocate outside the District of Columbia. The Pentagon , built in Arlington during World War II as the headquarters of the Department of Defense, was struck by a hijacked plane in the September 11, 2001 attacks . Mass shootings at Virginia Tech in 2007 and in Virginia Beach in 2019 led to passage of gun control measures in 2020. Racial injustice and
7056-570: The Marconi Research Centre 2MT at Writtle near Chelmsford, England . A famous broadcast from Marconi's New Street Works factory in Chelmsford was made by the famous soprano Dame Nellie Melba on June 15, 1920, where she sang two arias and her famous trill. She was the first artist of international renown to participate in direct radio broadcasts. The 2MT station began to broadcast regular entertainment in 1922. The BBC
7203-779: The Powhatan . In 1607, the London Company established the Colony of Virginia as the first permanent English colony in the New World , leading to Virginia's nickname as the Old Dominion . Slaves from Africa and land from displaced native tribes fueled the growing plantation economy, but also fueled conflicts both inside and outside the colony. Virginians fought for the independence of the Thirteen Colonies in
7350-635: The Southwest Mountains around Charlottesville . The Blue Ridge Mountains are a physiographic province of the Appalachian Mountains with the highest points in the Commonwealth, the tallest being Mount Rogers at 5,729 feet (1,746 m). The Ridge-and-Valley region is west of the mountains, carbonate rock based, and includes the Massanutten Mountain ridge and the Great Appalachian Valley , which
7497-723: The Torpedo Factory in Alexandria had over 5,050. High-school student Barbara Rose Johns started a strike in 1951 at her underfunded and segregated school in Prince Edward County . The protests led Spottswood Robinson and Oliver Hill to file a lawsuit against the county . Their case joined Brown v. Board of Education at the Supreme Court, which rejected the doctrine of " separate but equal " in 1954. The segregationist establishment, led by Senator Harry F. Byrd and his Byrd Organization , reacted with
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#17327804258407644-607: The Virginia big-eared bat , the state mammal . The Virginia opossum is the only marsupial native to the United States and Canada, and the native Appalachian cottontail was recognized in 1992 as a distinct species of rabbit, one of three found in the state. Whales, dolphins, and porpoises have been recorded in Virginia's coastal waters, with bottlenose dolphins being the most frequent aquatic mammals . Virginia's bird fauna comprises 422 counted species, of which 359 are regularly occurring and 214 have bred in Virginia, while
7791-555: The breeding of slaves , often through rape, a profitable business. Slaves in the Richmond area were also forced into industrial jobs, including mining and shipbuilding. The failed slave uprisings of Gabriel Prosser in 1800, George Boxley in 1815, and Nat Turner in 1831, however, marked the growing resistance to slavery. Afraid of further uprisings, Virginia's government in the 1830s encouraged free Blacks to migrate to Liberia . On October 16, 1859, abolitionist John Brown led
7938-483: The class divide by disenfranchising and restricting the movement of indentured servants, who made up around eighty percent of the workforce. On the colony's frontier, tribes like the Tutelo and Doeg were being squeezed by Seneca raiders from the north, leading to more confrontations with colonists. In 1676, several hundred working-class followers of Nathaniel Bacon , upset by Berkeley's refusal to retaliate against
8085-606: The headright system tried to solve this by granting colonists farmland for their help attracting indentured servants . Enslaved Africans were first sold in Virginia in 1619. Though other Africans arrived as indentured servants and could be freed after four to seven years, the basis for lifelong slavery was developed in legal cases like those of John Punch in 1640 and John Casor in 1655. Laws passed in Jamestown defined slavery as race-based in 1661, as inherited maternally in 1662, and as enforceable by death in 1669. From
8232-516: The medium wave frequency range of 525 to 1,705 kHz (known as the "standard broadcast band"). The band was expanded in the 1990s by adding nine channels from 1,605 to 1,705 kHz. Channels are spaced every 10 kHz in the Americas , and generally every 9 kHz everywhere else. AM transmissions cannot be ionospheric propagated during the day due to strong absorption in the D-layer of
8379-766: The siege of Yorktown . His surrender on October 19, 1781, led to peace negotiations in Paris and secured the independence of the colonies. Virginians were instrumental in writing the United States Constitution : James Madison drafted the Virginia Plan in 1787 and the Bill of Rights in 1789. Virginia ratified the Constitution on June 25, 1788. The three-fifths compromise ensured that Virginia, with its large number of slaves, initially had
8526-446: The state fish . Downhill in the Piedmont, stripeback darter and Roanoke bass become common, as do swampfish , bluespotted sunfish , and pirate perch in the Tidewater . The Chesapeake Bay hosts clams, oysters, and 350 species of saltwater and estuarine fish , including the bay's most abundant finfish, the Bay anchovy , as well as the invasive blue catfish . An estimated 317 million Chesapeake blue crabs live in
8673-497: The "Virgin Queen" or that they viewed the land as being untouched) or related to an Algonquin phrase, Wingandacoa or Windgancon , or leader's name, Wingina , as heard by the expedition. The name initially applied to the entire coastal region from South Carolina in the south to Maine in the north, along with the island of Bermuda . Raleigh's colony failed, but the potential financial and strategic gains still captivated many English policymakers. In 1606, King James I issued
8820-441: The 1930s to over one million by the 2010s. Native carnivorans include black bears , who have a population of around five to six thousand in the state, as well as bobcats , coyotes , both gray and red foxes , raccoons , weasels and skunks . Rodents include groundhogs , nutria , beavers , both gray squirrels and fox squirrels , chipmunks, and Allegheny woodrats , while the seventeen bat species include brown bats and
8967-507: The 1960s to the 1980s was What is Communism? A second reason is to advance a nation's foreign policy interests and agenda by disseminating its views on international affairs or on the events in particular parts of the world. During the Cold War the American Radio Free Europe and Radio Liberty and Indian Radio AIR were founded to broadcast news from "behind the Iron Curtain " that was otherwise being censored and promote dissent and occasionally, to disseminate disinformation . Currently,
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#17327804258409114-416: The 2022–2023 winter season. Climate change in Virginia is leading to higher temperatures year-round as well as more heavy rain and flooding events. Urban heat islands can be found in many Virginia cities and suburbs, particularly in neighborhoods linked to historic redlining . The air in Virginia has statistically improved since 1998. The closure and conversion of coal power plants in Virginia and
9261-478: The 76 to 90 MHz frequency band. Edwin Howard Armstrong invented wide-band FM radio in the early 1930s to overcome the problem of radio-frequency interference (RFI), which plagued AM radio reception. At the same time, greater fidelity was made possible by spacing stations further apart in the radio frequency spectrum. Instead of 10 kHz apart, as on the AM band in the US, FM channels are 200 kHz (0.2 MHz) apart. In other countries, greater spacing
9408-427: The Appalachian Mountains can lead to significant snowfalls across the state, such as the January 2016 blizzard , which created the state's highest recorded one-day snowfall of 36.6 inches (93 cm) near Bluemont . On average, cities in Virginia can receive between 5.8–12.3 inches (15–31 cm) of snow annually, but recent winters have seen below-average snowfalls, and much of Virginia had no measurable snow during
9555-678: The Black population was reduced by the Great Migration to northern industrial cities in the first half of the 20th century, since 1965 there has been a reverse migration of Blacks returning south . The Commonwealth has the highest number of Black-white interracial marriages in the US , and 8.2% of Virginians describe themselves as multiracial . More recent immigration since the late 20th century has resulted in new communities of Hispanics and Asians. As of 2020 , 10.5% of Virginia's total population describe themselves as Hispanic or Latino , and 8.8% as Asian . The state's Hispanic population rose by 92% from 2000 to 2010, with two-thirds of Hispanics in
9702-399: The Census Bureau recognizes several hundred unincorporated communities . Over three million people, 35% of Virginians, live in the twenty jurisdictions collectively defined as Northern Virginia , part of the larger Washington metropolitan area and the Northeast megalopolis . Fairfax County , with more than 1.1 million residents, is Virginia's most populous jurisdiction, and has
9849-469: The Civil War, the Commonwealth was deeply in debt, and in the late 1870s redirected money from public schools to pay bondholders. The Readjuster Party formed in 1877 and won legislative power in 1879 by uniting Black and white Virginians behind a shared opposition to debt payments and the perceived plantation elites . The Readjusters focused on building up schools, like Virginia Tech and Virginia State , and successfully forced West Virginia to share in
9996-577: The Great Dismal and Nottoway swamps. Other common trees include red spruce, Atlantic white cedar , tulip-poplar , and the flowering dogwood , the state tree and flower . Plants like milkweed , dandelions, daisies, ferns, and Virginia creeper , which is featured on the state flag , are also common. The Thompson Wildlife Area in Fauquier is known for having one of the largest populations of trillium wildflowers in North America. White-tailed deer , one of 75 mammal species found in Virginia, rebounded from an estimated population of as few as 25,000 in
10143-436: The Iroquois, and other allied tribes on both sides. A militia from several British colonies, called the Virginia Regiment , was led by Major George Washington , himself one of the investors in the Ohio Company. In the decade following the French and Indian War , the British Parliament passed new taxes which were deeply unpopular in the colonies, and in the House of Burgesses ; opposition to taxation without representation
10290-404: The Kentucky border and is one of only two inter-state parks in the United States. Sustainable logging is allowed in 26 state forests managed by the Virginia Department of Forestry totaling 71,972 acres (291.3 km ), as is hunting in 44 Wildlife Management Areas run by the Virginia Department of Wildlife Resources covering over 205,000 acres (829.6 km ). The Chesapeake Bay is not
10437-459: The May 23 referendum, armed pro-Confederate groups prevented the casting and counting of votes from areas that opposed secession. Representatives from 27 of these northwestern counties instead began the Wheeling Convention , which organized a government loyal to the Union and led to the separation of West Virginia as a new state. The armies of the Union and Confederacy first met on July 21, 1861, in Battle of Bull Run near Manassas, Virginia ,
10584-555: The Ohio Valley region has helped cut the amount of particulate matter in Virginia's air in half. Current plans call for 30% of the Commonwealth's electricity to be renewable by 2030 and for all to be carbon-free by 2050. Forests cover 62% of Virginia as of 2021 , of which 80% is considered hardwood forest, meaning that trees are primarily deciduous and broad-leaved . The other 20% is pine, with loblolly and shortleaf pine dominating much of central and eastern Virginia. In
10731-506: The U.S. Federal Communications Commission designates the 88–92 megahertz band in the U.S. for non-profit or educational programming, with advertising prohibited. In addition, formats change in popularity as time passes and technology improves. Early radio equipment only allowed program material to be broadcast in real time, known as live broadcasting. As technology for sound recording improved, an increasing proportion of broadcast programming used pre-recorded material. A current trend
10878-655: The U.S. Census Bureau found that only 0.5% of Virginians were exclusively American Indian or Alaska Native , though 2.1% were in some combination with other ethnicities. The state government has extended recognition to eleven tribes. Seven tribes also have federal recognition. The Pamunkey and Mattaponi have reservations on tributaries of the York River in the Tidewater region . [REDACTED] American Community Survey five-year estimate According to U.S. Census data as of 2022 on Virginia residents aged five and older, 83% (6,805,548) speak English at home as
11025-603: The U.S. are under Coles Hill, Virginia . Despite a challenge that reached the U.S. Supreme Court twice , the state has banned its mining since 1982 due to environmental and public health concerns. Virginia has a humid subtropical climate that transitions to humid continental west of the Blue Ridge Mountains . Seasonal extremes vary from average lows of 25 °F (−4 °C) in January to average highs of 86 °F (30 °C) in July. The Atlantic Ocean and Gulf Stream have
11172-759: The US and Canada , just two services, XM Satellite Radio and Sirius Satellite Radio exist. Both XM and Sirius are owned by Sirius XM Satellite Radio , which was formed by the merger of XM and Sirius on July 29, 2008, whereas in Canada , XM Radio Canada and Sirius Canada remained separate companies until 2010. Worldspace in Africa and Asia, and MobaHO! in Japan and the ROK were two unsuccessful satellite radio operators which have gone out of business. Radio program formats differ by country, regulation, and markets. For instance,
11319-580: The US operates similar services aimed at Cuba ( Radio y Televisión Martí ) and the People's Republic of China , Vietnam , Laos and North Korea ( Radio Free Asia ). Besides ideological reasons, many stations are run by religious broadcasters and are used to provide religious education, religious music, or worship service programs. For example, Vatican Radio , established in 1931, broadcasts such programs. Another station, such as HCJB or Trans World Radio will carry brokered programming from evangelists. In
11466-639: The US use of 800 (kHz) and 900 non-directionally in Alaska, limited to 5 kW at night; and 1050 and 1220, directionally, in the continental US , and without time limits; each of these being assigned to specific cities (and each of these being Mexican Class I-A clear channels). In return for these limits on US stations, Mexico accepted limits on 830 and 1030 in Mexico City, non-directionally, restricted to 5 kW at night (both of these being US Class I-A clear channels). Notes: The following table lists
11613-437: The US were terminated at midnight Eastern Daylight Time on June 12, 2009. Many broadcasters replaced their analog signal with their digital ATSC signal on the same transmission channel at that time. Notes: LPTV (secondary) (suffix: -LP, or a sequential-numbered callsign in format W##XX with no suffix for analog or with -D suffix for digital, or -LD for low-power digital stations): The LPTV (low-power television) service
11760-812: The US, with subclasses indicated by a letter suffix. Current class A is equivalent to the old class I; class B is the old classes II and III, with class D being the II-D, II-S, and III-S subclasses; and class C is the old class IV. The following conversion table compares the old AM station classes with the new AM station classes: The following chart lists frequencies on the broadcast company band, and which classes broadcast on these frequencies; Class A and Class B , 10,000 watt and higher (full-time) stations in North America which broadcast on clear-channel station frequencies are also shown. By international agreement, Class A stations must be 10,000 watts and above, with
11907-628: The United States and Canada have chosen to use HD radio , an in-band on-channel system that puts digital broadcasts at frequencies adjacent to the analog broadcast. HD Radio is owned by a consortium of private companies that is called iBiquity . An international non-profit consortium Digital Radio Mondiale (DRM), has introduced the public domain DRM system, which is used by a relatively small number of broadcasters worldwide. Broadcasters in one country have several reasons to reach out to an audience in other countries. Commercial broadcasters may simply see
12054-478: The United States as of 2020 . El Salvador is the most common foreign country of birth, with India , Mexico , South Korea , the Philippines , and Vietnam as other common birthplaces. The state's most populous racial group, non-Hispanic whites , has declined as a proportion of the population from 76% in 1990 to 58.6% in 2020. Immigrants from Britain and Ireland settled throughout the Commonwealth during
12201-589: The United States came from KDKA itself: the results of the Harding/Cox Presidential Election . The Montreal station that became CFCF began broadcast programming on May 20, 1920, and the Detroit station that became WWJ began program broadcasts beginning on August 20, 1920, although neither held a license at the time. In 1920, wireless broadcasts for entertainment began in the UK from
12348-643: The United States, France, the Netherlands, South Africa, and many other countries worldwide. The simplest system is named DAB Digital Radio, for Digital Audio Broadcasting , and uses the public domain EUREKA 147 (Band III) system. DAB is used mainly in the UK and South Africa. Germany and the Netherlands use the DAB and DAB+ systems, and France uses the L-Band system of DAB Digital Radio. The broadcasting regulators of
12495-489: The United States. Virginia has a total area of 42,774.2 square miles (110,784.7 km ), including 3,180.13 square miles (8,236.5 km ) of water, making it the 35th- largest state by area. It is bordered by Maryland and Washington, D.C. to the northeast; by the Atlantic Ocean to the east; by North Carolina to the south; by Tennessee to the southwest; by Kentucky to the west; and by West Virginia to
12642-530: The Virginia General Assembly proposed a new surveying commission in 1871. Representatives from Tennessee preferred to keep the less-straight 1803 line, and in 1893, the U.S. Supreme Court ruled for them against Virginia . One result is how the city of Bristol is divided in two between the states. The Chesapeake Bay separates the contiguous portion of the Commonwealth from the two-county peninsula of Virginia's Eastern Shore . The bay
12789-457: The antenna site," based on the determined noise-limited bounding contour. All digital television stations in Mexico have -TDT callsign suffixes. Analog stations, which existed until December 31, 2016, had -TV callsign suffixes. The equivalent of low power or translator service in Mexico is the equipo complementario de zona de sombra , which is intended only to fill in gaps between a station's expected and actual service area caused by terrain;
12936-632: The area at that time included the Algonquian in the Tidewater region , which they referred to as Tsenacommacah , the Iroquoian -speaking Nottoway and Meherrin to the north and south, and the Tutelo , who spoke Siouan , to the west. In response to threats from these other groups to their trade network, thirty or so Virginia Algonquian -speaking tribes consolidated during the 1570s under Wahunsenacawh, known in English as Chief Powhatan . Powhatan controlled more than 150 settlements that had
13083-692: The area held by the Seneca and their larger Iroquois Nation , and in 1748, a group of wealthy speculators, backed by the British monarchy, formed the Ohio Company to start English settlement and trade in the Ohio Country west of the Appalachian Mountains . France, which claimed this area as part of New France , viewed this as a threat, and in 1754 the French and Indian War engulfed England, France,
13230-592: The areas south of latitude 43.5°N in Michigan , New Hampshire , New York, and Vermont ; as well as coastal Maine , southeastern Wisconsin , and northern and eastern Virginia . Zone I-A includes California south of 40°N, as well as Puerto Rico and the US Virgin Islands . Zone II includes the remainder of the continental US , plus Alaska and Hawaii . In Zones I and I-A, there are no Class C, C0, or C1 stations. However, there are
13377-714: The army and revolutionary militias. Virginia was the first colony to ratify the Articles of Confederation in December 1777. In April 1780, the capital was moved to Richmond at the urging of Governor Thomas Jefferson, who feared that Williamsburg's coastal location would make it vulnerable to British attack. British forces landed around Portsmouth in October 1780, and soldiers under Benedict Arnold raided Richmond in January 1781. The British army had over seven thousand soldiers and twenty-five warships stationed in Virginia at
13524-547: The bay as of 2024 . There are 34 native species of crayfish, like the Big Sandy . Amphibians found in Virginia include the Cumberland Plateau salamander and Eastern hellbender , while the northern watersnake is the most common of the 32 snake species. As of 2019 , roughly 16.2% of land in the Commonwealth is protected by federal, state, and local governments and non-profits. Federal lands account for
13671-566: The beginning of 1781, but General Charles Cornwallis and his superiors were indecisive, and maneuvers by the three thousand soldiers under the Marquis de Lafayette and twenty-nine allied French warships together managed to confine the British to a swampy area of the Virginia Peninsula in September. Around sixteen thousand soldiers under George Washington and Comte de Rochambeau quickly converged there and defeated Cornwallis in
13818-728: The case of the Broadcasting Services of the Kingdom of Saudi Arabia , both governmental and religious programming is provided. Extensions of traditional radio-wave broadcasting for audio broadcasting in general include cable radio , local wire television networks , DTV radio , satellite radio , and Internet radio via streaming media on the Internet . The enormous entry costs of space-based satellite transmitters and restrictions on available radio spectrum licenses has restricted growth of Satellite radio broadcasts. In
13965-722: The college teamed up with WLOE in Boston to have students broadcast programs. By 1931, a majority of U.S. households owned at least one radio receiver . In line to ITU Radio Regulations (article1.61) each broadcasting station shall be classified by the service in which it operates permanently or temporarily. Broadcasting by radio takes several forms. These include AM and FM stations. There are several subtypes, namely commercial broadcasting , non-commercial educational (NCE) public broadcasting and non-profit varieties as well as community radio , student-run campus radio stations, and hospital radio stations can be found throughout
14112-528: The colonial period, when roughly three-fourths of immigrants came as indentured servants . The Appalachian mountains and Shenandoah Valley have many settlements that were populated by German and Scotch-Irish immigrants in the 18th and 19th centuries, often following the Great Wagon Road . Over ten percent of Virginians have German ancestry as of 2020 . The largest minority group in Virginia are Blacks and African Americans, about one-fifth of
14259-585: The colonial period. Only three other independent cities exist elsewhere in the US. The differences between counties and cities in Virginia are small and have to do with how each assess new taxes, whether a referendum is necessary to issue bonds, and with the application of Dillon's Rule , which limits the authority of cities and counties to countermand acts expressly allowed by the General Assembly . Counties can also have incorporated towns , and while there are no further administrative subdivisions ,
14406-557: The colony's start, residents agitated for greater local control, and in 1619, certain male colonists began electing representatives to an assembly, later called the House of Burgesses , that negotiated issues with the governing council appointed by the London Company. Unhappy with this arrangement, the monarchy revoked the company's charter and began directly naming governors and Council members in 1624. In 1635, colonists arrested
14553-714: The company and the Carver Corporation later cut the number of models produced before discontinuing production completely. As well as on the medium wave bands, amplitude modulation (AM) is also used on the shortwave and long wave bands. Shortwave is used largely for national broadcasters, international propaganda, or religious broadcasting organizations. Shortwave transmissions can have international or inter-continental range depending on atmospheric conditions. Long-wave AM broadcasting occurs in Europe, Asia, and Africa. The ground wave propagation at these frequencies
14700-517: The concentration of independent cities in the Tidewater region is that several rural counties there re-incorporated as cities or consolidated with existing cities to try to hold on to their new suburban neighborhoods that started booming in the 1950s , since cities like Norfolk and Portsmouth were able to annex land from adjoining counties until a moratorium in 1987. Others, like Poquoson , became cities to try to preserve racial segregation during
14847-467: The country at night. During the night, absorption largely disappears and permits signals to travel to much more distant locations via ionospheric reflections. However, fading of the signal can be severe at night. AM radio transmitters can transmit audio frequencies up to 15 kHz (now limited to 10 kHz in the US due to FCC rules designed to reduce interference), but most receivers are only capable of reproducing frequencies up to 5 kHz or less. At
14994-409: The desegregation era of the 1970s. The 2020 census found the state resident population was 8,631,393, a 7.9% increase since the 2010 census . Another 23,149 Virginians live overseas, giving the state a total population of 8,654,542. Virginia has the fourth-largest overseas population of U.S. states due to its federal employees and military personnel. The fertility rate in Virginia as of 2020
15141-486: The dominant medium, especially in cities. Because of its greater range, AM remained more common in rural environments. Pirate radio is illegal or non-regulated radio transmission. It is most commonly used to describe illegal broadcasting for entertainment or political purposes. Sometimes it is used for illegal two-way radio operation. Its history can be traced back to the unlicensed nature of the transmission, but historically there has been occasional use of sea vessels—fitting
15288-541: The eastern edge is the Hampton Roads metropolitan area, where over 1.7 million reside across six counties and nine cities, including the Commonwealth's three most populous independent cities: Virginia Beach , Chesapeake , and Norfolk . Neighboring Suffolk , which includes a portion of the Great Dismal Swamp , is the largest city by area at 429.1 square miles (1,111 km ). One reason for
15435-500: The end of slavery across the country. The seizure of Fort Sumter by Confederate forces on April 14, 1861, prompted Lincoln to call for a federal army of 75,000 men from state militias . The Virginia Secession Convention of 1861 voted on April 17 to secede on the condition it was approved in a referendum the next month. The convention voted to join the Confederacy, which named Richmond its capital on May 20. During
15582-403: The first of several invasions into Union territory. During the next three years of war, more battles were fought in Virginia than anywhere else, including the battles of Fredericksburg , Chancellorsville , Spotsylvania , and the concluding Battle of Appomattox Court House , where Lee surrendered on April 9, 1865. Virginia was formally restored to the United States in 1870, due to the work of
15729-583: The highest and lowest sidebands is quite apparent to the listener. Such distortion occurs up to frequencies of approximately 50 MHz. Higher frequencies do not reflect from the ionosphere, nor from storm clouds. Moon reflections have been used in some experiments, but require impractical power levels. The original FM radio service in the U.S. was the Yankee Network , located in New England . Regular FM broadcasting began in 1939 but did not pose
15876-411: The ionosphere. In a crowded channel environment, this means that the power of regional channels which share a frequency must be reduced at night or directionally beamed in order to avoid interference, which reduces the potential nighttime audience. Some stations have frequencies unshared with other stations in North America; these are called clear-channel stations . Many of them can be heard across much of
16023-578: The land on Virginia's islands, which include Tangier Island in the bay and Chincoteague , one of 23 barrier islands on the Atlantic coast. The Tidewater is a coastal plain between the Atlantic coast and the fall line . It includes the Eastern Shore and major estuaries of Chesapeake Bay. The Piedmont is a series of sedimentary and igneous rock -based foothills east of the mountains. The region, known for its heavy clay soil, includes
16170-466: The largest bloc in the House of Representatives . Together with the Virginia dynasty of presidents, this gave the Commonwealth national importance. Virginia is called the "Mother of States" because of its role in being carved into states such as Kentucky , and for the numbers of American pioneers born in Virginia. Between 1790 and 1860, the number of slaves in Virginia rose from around 290 thousand to over 490 thousand, roughly one-third of
16317-440: The late afternoon and evenings between April and September. These months are also the most common for tornadoes , eight of which touched down in the Commonwealth in 2023. Hurricanes and tropical storms can occur from August to October. The deadliest natural disaster in Virginia was Hurricane Camille , which killed over 150 people in 1969 mainly in inland Nelson County . Between December and March, cold-air damming caused by
16464-873: The majority, with thirty National Park Service units, such as Great Falls Park and the Appalachian Trail , and one national park, Shenandoah . Almost forty percent of Shenandoah's total 199,173 acres (806 km ) area has been designated as wilderness under the National Wilderness Preservation System . The U.S. Forest Service administers the George Washington and Jefferson National Forests , which cover more than 1.6 million acres (6,500 km ) within Virginia's mountains, and continue into West Virginia and Kentucky . The Great Dismal Swamp National Wildlife Refuge also extends into North Carolina, as does
16611-620: The middle of the 20th century, are the focus of conservation efforts in the state and a reintroduction program in Shenandoah National Park . Virginia has 226 species of freshwater fish from 25 families, a diversity attributable to the area's varied and humid climate, topography, interconnected river system, and lack of Pleistocene glaciers . Common examples on the Cumberland Plateau and higher-elevation regions include Eastern blacknose dace , sculpin , smallmouth bass , redhorse sucker , Kanawha darter , and brook trout ,
16758-402: The most common perception of a pirate—as broadcasting bases. Rules and regulations vary largely from country to country, but often the term pirate radio describes the unlicensed broadcast of FM radio, AM radio, or shortwave signals over a wide range. In some places, radio stations are legal where the signal is transmitted, but illegal where the signals are received—especially when the signals cross
16905-489: The new band had to begin from the ground floor. As a commercial venture, it remained a little-used audio enthusiasts' medium until the 1960s. The more prosperous AM stations, or their owners, acquired FM licenses and often broadcast the same programming on the FM station as on the AM station (" simulcasting "). The FCC limited this practice in the 1960s. By the 1980s, since almost all new radios included both AM and FM tuners, FM became
17052-474: The north and drifted an additional 3.5 miles by the border's westernmost point . After Tennessee joined the U.S. in 1796, new surveyors worked in 1802 and 1803 to reset their border with Virginia as a line from the summit of White Top Mountain to the top of Tri-State Peak in the Cumberland Mountains . However, deviations in that border were identified when it was re-marked in 1856, and
17199-466: The northwest. That Virginia's boundary with Maryland and Washington, D.C. only extends to the low-water mark of the south shore of the Potomac River has been an issue for water rights over the years. . Virginia's southern border was defined in 1665 as 36°30' north latitude . Surveyors marking the border with North Carolina in the 18th century however started about 3.5 miles (5.6 km) to
17346-427: The only stations currently authorized to broadcast both analog and digital signals, unlike full-power stations which must broadcast a digital signal only. In Canada, there is no formal transmission power below which a television transmitter is considered broadcasting at low power. Industry Canada considers that a low power digital television undertaking "shall not normally extend a distance of 20 km in any direction from
17493-518: The population. Virginia was a major destination of the Atlantic slave trade . The Igbo ethnic group of what is now southern Nigeria were the largest African group among slaves in Virginia. Blacks in Virginia also have more European ancestry than those in other southern states, and DNA analysis shows many have asymmetrical male and female ancestry from before the Civil War, evidence of European fathers and African or Native American mothers. Though
17640-620: The pre-war debt. But in 1883, they were divided by a proposed repeal of anti-miscegenation laws , and days before that year's election, a riot in Danville , involving armed policemen, left four Black men and one white man dead. These events motivated a push by white supremacists to seize political power through voter suppression , and segregationists in the Democratic Party won the legislature that year and maintained control for decades. They passed Jim Crow laws that established
17787-518: The presence of Confederate monuments in Virginia have also led to large demonstrations, including in August 2017, when a white supremacist drove his car into protesters , killing one, and in June 2020, when protests that were part of the larger Black Lives Matter movement brought about the removal of Confederate statues . Virginia is located in the Mid-Atlantic and Southeastern regions of
17934-455: The range of a given FM signal was much shorter; thus its market was more local than for AM radio. The reception range at night is the same as in the daytime. All FM broadcast transmissions are line-of-sight, and ionospheric bounce is not viable. The much larger bandwidths, compared to AM and SSB, are more susceptible to phase dispersion. Propagation speeds are fastest in the ionosphere at the lowest sideband frequency. The celerity difference between
18081-691: The repeal of Jim Crow laws in the 1970s. Virginia's state legislature is the Virginia General Assembly , which was established in July 1619, making it the oldest current law-making body in North America . Unlike other states, cities and counties in Virginia function as equals, but the state government manages most local roads. It is also the only state where governors are prohibited from serving consecutive terms. Nomadic hunters are estimated to have arrived in Virginia around 17,000 years ago. Evidence from Daugherty's Cave shows it
18228-469: The rest are mostly winter residents or transients . Water birds include sandpipers, wood ducks, and Virginia rail , while common inland examples include warblers, woodpeckers, and cardinals, the state bird . Birds of prey include osprey, broad-winged hawks , and barred owls . There are no endemic bird species. Audubon recognizes 21 Important Bird Areas in the state. Peregrine falcons , whose numbers dramatically declined due to DDT poisoning in
18375-475: The reverse direction because the plate was not heated, and thus not capable of thermionic emission of electrons. Later known as the Fleming valve , it could be used as a rectifier of alternating current, and as a radio wave detector . This greatly improved the crystal set , which rectified the radio signal using an early solid-state diode based on a crystal and a so-called cat's whisker . However, an amplifier
18522-410: The same service area. This prevents the sideband power generated by two stations from interfering with each other. Bob Carver created an AM stereo tuner employing notch filtering that demonstrated that an AM broadcast can meet or exceed the 15 kHz baseband bandwidth allotted to FM stations without objectionable interference. After several years, the tuner was discontinued. Bob Carver had left
18669-686: The state living in Northern Virginia . Northern Virginia also has a significant population of Vietnamese Americans , whose major wave of immigration followed the Vietnam War . Korean Americans have migrated there more recently, while about 45,000 Filipino Americans have settled in the Hampton Roads area. Tribal membership in Virginia is complicated by the legacy of the state's " pencil genocide " of intentionally categorizing Native Americans and Blacks together, and many tribal members do have African or European ancestry, or both. In 2020,
18816-587: The state population, and the number of slave owners rose to over 50 thousand. Both of these numbers represented the most in the U.S. The boom in Southern cotton production using cotton gins increased the amount of labor needed for harvesting raw cotton , but new federal laws prohibited the importation of slaves. Decades of monoculture tobacco farming had also degraded Virginia's agricultural productivity . Virginia plantations increasingly turned to exporting slaves , which broke up countless families and made
18963-545: The state than moving to it in 2021. This is largely credited to high home prices in Northern Virginia, which are driving residents there to relocate south; Raleigh is their top destination. Aside from Virginia, the top birth state for Virginians is New York , with the Northeast accounting for the largest number of domestic migrants into the state by region. About twelve percent of residents were born outside
19110-534: The station was moved to the top of the Westinghouse factory building in East Pittsburgh, Pennsylvania . Westinghouse relaunched the station as KDKA on November 2, 1920, as the first commercially licensed radio station in the United States. The commercial broadcasting designation came from the type of broadcast license ; advertisements did not air until years later. The first licensed broadcast in
19257-408: The time that AM broadcasting began in the 1920s, this provided adequate fidelity for existing microphones, 78 rpm recordings, and loudspeakers. The fidelity of sound equipment subsequently improved considerably, but the receivers did not. Reducing the bandwidth of the receivers reduces the cost of manufacturing and makes them less prone to interference. AM stations are never assigned adjacent channels in
19404-432: The tribes, burned Jamestown. Bacon's Rebellion forced the signing of Bacon's Laws , which restored some of the colony's rights and sanctioned both attacks on native tribes and the enslavement of their people. The Treaty of 1677 further reduced the independence of the tribes that signed it, and aided the colony's assimilation of their land in the years that followed. Colonists in the 1700s were pushing westward into
19551-709: The various classes of FM stations, the reference facilities for each station class, and the protected and city grade contours for each station class: Historically, there were local "Class A" frequencies (like AM radio's class C stations) to which only class A stations would be allocated & the other frequencies could not have a class A. According to the 1982 FCC rules & regulations, those frequencies were: 92.1, 92.7, 93.5, 94.3, 95.3, 95.9, 96.7, 97.7, 98.3, 99.3, 100.1, 100.9, 101.7, 102.3, 103.1, 103.9, 104.9, 105.5, 106.3 & 107.1. Stations on those twenty frequencies were limited to having equivalent signals no greater that 3KW at 300 feet (91 meters) above average terrain. The US
19698-483: The western and mountainous parts of the Commonwealth, oak and hickory are most common, while lower altitudes are more likely to have small but dense stands of hemlocks and mosses in abundance. Spongy moth infestations in oak trees and the blight in chestnut trees have decreased both of their numbers, leaving more room for hickory and the invasive tree of heaven . In the lowland tidewater and Piedmont , yellow pines tend to dominate, with bald cypress wetland forests in
19845-505: The world. Many stations broadcast on shortwave bands using AM technology that can be received over thousands of miles (especially at night). For example, the BBC , VOA , VOR , and Deutsche Welle have transmitted via shortwave to Africa and Asia. These broadcasts are very sensitive to atmospheric conditions and solar activity. Nielsen Audio , formerly known as Arbitron, the United States –based company that reports on radio audiences, defines
19992-482: Was 55.8 per 1,000 females between the ages of 15 and 44, and the median age as of 2021 was the same as the national average of 38.8 years old. The geographic center of population is located northwest of Richmond in Hanover County , as of 2020 . Though still growing naturally as births outnumber deaths, Virginia has had a negative net migration rate since 2013, with 8,995 more people leaving
20139-530: Was amalgamated in 1922 and received a Royal Charter in 1926, making it the first national broadcaster in the world, followed by Czechoslovak Radio and other European broadcasters in 1923. Radio Argentina began regularly scheduled transmissions from the Teatro Coliseo in Buenos Aires on August 27, 1920, making its own priority claim. The station got its license on November 19, 1923. The delay
20286-513: Was carrying audio by the next year. (Herrold's station eventually became KCBS ). In The Hague, the Netherlands, PCGG started broadcasting on November 6, 1919, making it arguably the first commercial broadcasting station. In 1916, Frank Conrad , an electrical engineer employed at the Westinghouse Electric Corporation , began broadcasting from his Wilkinsburg, Pennsylvania garage with the call letters 8XK. Later,
20433-489: Was created in 1982 by the FCC to allocate channels for smaller, local stations, and community channels, such as public access stations. LPTV stations that meet additional requirements such as children's " E/I " core programming and Emergency Alert System broadcasting capabilities can qualify for a Class A (-CA) license. Broadcast translators , boosters , and other LPTV stations are considered secondary to full-power stations, unless they have upgraded to class A. Class A
20580-460: Was due to the lack of official Argentine licensing procedures before that date. This station continued regular broadcasting of entertainment, and cultural fare for several decades. Radio in education soon followed, and colleges across the U.S. began adding radio broadcasting courses to their curricula. Curry College in Milton, Massachusetts introduced one of the first broadcasting majors in 1932 when
20727-518: Was formed from the drowned river valley of the ancient Susquehanna River . Many of Virginia's rivers flow into the Chesapeake Bay, including the Potomac , Rappahannock , York , and James , which create three peninsulas in the bay, traditionally referred to as "necks" named Northern Neck , Middle Peninsula , and the Virginia Peninsula from north to south. Sea level rise has eroded
20874-759: Was led by Patrick Henry and Richard Henry Lee , among others. Virginians began to coordinate their actions with other colonies in 1773 and sent delegates to the Continental Congress the following year. After the House of Burgesses was dissolved in 1774 by the royal governor , Virginia's revolutionary leaders continued to govern via the Virginia Conventions . On May 15, 1776, the Convention declared Virginia's independence and adopted George Mason 's Virginia Declaration of Rights , which
21021-537: Was quickly becoming viable. However, an early audio transmission that could be termed a broadcast may have occurred on Christmas Eve in 1906 by Reginald Fessenden , although this is disputed. While many early experimenters attempted to create systems similar to radiotelephone devices by which only two parties were meant to communicate, there were others who intended to transmit to larger audiences. Charles Herrold started broadcasting in California in 1909 and
21168-426: Was regularly used as a rock shelter by 9,800 years ago. During the late Woodland period (500–1000 CE ), tribes coalesced, and farming, first of corn and squash, began, with beans and tobacco arriving from the southwest and Mexico by the end of the period. Palisaded towns began to be built around 1200. The native population in the current boundaries of Virginia reached around 50,000 in the 1500s. Large groups in
21315-696: Was responsible for building 38 warships for the U.S. Navy between 1907 and 1923. During World War I , German submarines attacked ships outside the port, which was a major site for transportation of soldiers and supplies. After the war, a homecoming parade to honor African-American troops was attacked in July 1919 by the city's police as part of a renewed white-supremacy movement, known as Red Summer . The shipyard continued building warships in World War II , and quadrupled its pre-war labor force to 70,000 by 1943. The Radford Arsenal outside Blacksburg also employed 22,000 workers making explosives, while
21462-494: Was still required. The triode (mercury-vapor filled with a control grid) was created on March 4, 1906, by the Austrian Robert von Lieben ; independently, on October 25, 1906, Lee De Forest patented his three-element Audion . It was not put to practical use until 1912 when its amplifying ability became recognized by researchers. By about 1920, valve technology had matured to the point where radio broadcasting
21609-687: Was then included in a new constitution that designated Virginia as a commonwealth . Another Virginian, Thomas Jefferson , drew upon Mason's work in drafting the national Declaration of Independence . After the American Revolutionary War began, George Washington was selected by the Second Continental Congress in Philadelphia to head the Continental Army , and many Virginians joined
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