Carrier current
Encyclopedia
Carrier current is a method of low power
AM
radio transmission that uses the AC electrical system
of a building to propagate a medium frequency
, AM signal to a relatively small area, such as a building or a group of buildings. In the United States
, carrier current stations do not require a broadcasting
license from the FCC
, as long as the emissions adhere to the Part 15 Rules for unlicensed transmissions.
This technique is used by many types of facilities that need to transmit radio to a small area. Carrier current is most often associated with college radio, high school radio
, and hospital radio
stations, but is also used at military bases, sports stadiums, convention halls, mental and penal institutions, trailer park
s, summer camp
s, office buildings, and drive-in movie theaters
. Many college stations that went on to obtain broadcasting licenses, started out as carrier current stations because of the low cost and relative ease of starting up such a radio station
.
Carrier current stations generally operate with very low power. A typical transmitter might be 5 to 30 watt
s, although using a building's AC wiring as an antenna is very inefficient results in an effective radiated power
of less than one watt. The usable range of the signal is usually less than 200 feet (60 meters). These signals cannot pass through utility transformer
s, however, and are prone to the electromagnetic interference
from alternating current
. Transmitters that use carrier current are very simple, making them an effective option for students interested in radio. Transmissions can be of good quality, although there is a low frequency background hum
(60 hertz
in North America
n installations) associated with carrier current, due to the alternating current. Not all listeners notice this hum, nor is it reproduced well by all receivers.
There are many examples of community radio
stations being operated in the United States using carrier current AM broadcasting. Signals may pass a transformer if the utility company has bypass lines installed (typically when non-conflicting carrier current-based data systems of their own are in operation). Signals may also be impressed onto the neutral leg of the 3-phase power system, a practice known as "neutral loading", in an effort both to reduce (sometimes eliminate) 60 Hz hum, and to extend effective transmission line distance. It has been successful in both ways in community and campus installations.
Extensive systems can include multiple unit installations with linear amplifier
s and splitters to increase the coupling points to a large electrical grid (whether a campus, a high-rise apartment or a community). These systems would typically require coaxial cable interconnection from a transmitter to the linear amplifiers. In the 1990s, LPB, Inc., possibly the largest manufacturer of these transmission systems, designed and supplied several extensive campus-based systems that included fiber-optic links between linear amplifiers to prevent heterodyne interference.
Because of their simple design and the fact that the transmitter doesn't need an external antenna, carrier current listening devices have found some use in the world of espionage
.
, and streaming audio. Many carrier current stations have been, and continue to be, replaced by these technologies as well. Though legal, these stations are not licensed by the FCC
and their call letters
are entirely self-styled.
Low-power broadcasting
Low-power broadcasting is electronic broadcasting at very low power and low cost, to a small community area.The terms "low-power broadcasting" and "micropower broadcasting" should not be used interchangeably, because the markets are not the same...
AM
Amplitude modulation
Amplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...
radio transmission that uses the AC electrical system
Mains electricity
Mains is the general-purpose alternating current electric power supply. In the US, electric power is referred to by several names including household power, household electricity, powerline, domestic power, wall power, line power, AC power, city power, street power, and grid power...
of a building to propagate a medium frequency
Medium frequency
Medium frequency refers to radio frequencies in the range of 300 kHz to 3 MHz. Part of this band is the medium wave AM broadcast band. The MF band is also known as the hectometer band or hectometer wave as the wavelengths range from ten down to one hectometers...
, AM signal to a relatively small area, such as a building or a group of buildings. In the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, carrier current stations do not require a broadcasting
Broadcasting
Broadcasting is the distribution of audio and video content to a dispersed audience via any audio visual medium. Receiving parties may include the general public or a relatively large subset of thereof...
license from the FCC
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...
, as long as the emissions adhere to the Part 15 Rules for unlicensed transmissions.
This technique is used by many types of facilities that need to transmit radio to a small area. Carrier current is most often associated with college radio, high school radio
High school radio
High school radio within the United States is almost as old as radio broadcasting itself. Simply defined as a radio station, with its studios located at a high school and usually operated by its students with faculty supervision, stations fitting this description existed in the mid-1920s...
, and hospital radio
Hospital radio
Hospital radio is a form of audio broadcasting produced specifically for the in-patients of hospitals. It is primarily found in the United Kingdom.-History:...
stations, but is also used at military bases, sports stadiums, convention halls, mental and penal institutions, trailer park
Trailer park
A trailer park is a semi-permanent or permanent area for mobile homes or travel trailers. The main reasons for living in such trailer parks are the often lower cost compared to other housing, and the ability to move to a new area more quickly and easily, for example when changing jobs to another...
s, summer camp
Summer camp
Summer camp is a supervised program for children or teenagers conducted during the summer months in some countries. Children and adolescents who attend summer camp are known as campers....
s, office buildings, and drive-in movie theaters
Drive-in theater
A drive-in theater is a form of cinema structure consisting of a large outdoor screen, a projection booth, a concession stand and a large parking area for automobiles. Within this enclosed area, customers can view movies from the privacy and comfort of their cars.The screen can be as simple as a...
. Many college stations that went on to obtain broadcasting licenses, started out as carrier current stations because of the low cost and relative ease of starting up such a radio station
Radio station
Radio broadcasting is a one-way wireless transmission over radio waves intended to reach a wide audience. Stations can be linked in radio networks to broadcast a common radio format, either in broadcast syndication or simulcast or both...
.
Carrier current stations generally operate with very low power. A typical transmitter might be 5 to 30 watt
Watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
s, although using a building's AC wiring as an antenna is very inefficient results in an effective radiated power
Effective radiated power
In radio telecommunications, effective radiated power or equivalent radiated power is a standardized theoretical measurement of radio frequency energy using the SI unit watts, and is determined by subtracting system losses and adding system gains...
of less than one watt. The usable range of the signal is usually less than 200 feet (60 meters). These signals cannot pass through utility transformer
Transformer
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field...
s, however, and are prone to the electromagnetic interference
Electromagnetic interference
Electromagnetic interference is disturbance that affects an electrical circuit due to either electromagnetic induction or electromagnetic radiation emitted from an external source. The disturbance may interrupt, obstruct, or otherwise degrade or limit the effective performance of the circuit...
from alternating current
Alternating current
In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
. Transmitters that use carrier current are very simple, making them an effective option for students interested in radio. Transmissions can be of good quality, although there is a low frequency background hum
Mains hum
Mains hum, electric hum, or power line hum is an audible oscillation of alternating current at the frequency of the mains electricity, which is usually 50 Hz or 60 Hz, depending on the local power line frequency...
(60 hertz
Hertz
The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....
in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
n installations) associated with carrier current, due to the alternating current. Not all listeners notice this hum, nor is it reproduced well by all receivers.
There are many examples of community radio
Community radio
Community radio is a type of radio service, that offers a third model of radio broadcasting beyond commercial broadcasting and public broadcasting. Community stations can serve geographic communities and communities of interest...
stations being operated in the United States using carrier current AM broadcasting. Signals may pass a transformer if the utility company has bypass lines installed (typically when non-conflicting carrier current-based data systems of their own are in operation). Signals may also be impressed onto the neutral leg of the 3-phase power system, a practice known as "neutral loading", in an effort both to reduce (sometimes eliminate) 60 Hz hum, and to extend effective transmission line distance. It has been successful in both ways in community and campus installations.
Extensive systems can include multiple unit installations with linear amplifier
Linear amplifier
A linear amplifier is an electronic circuit whose output is proportional to its input, but capable of delivering more power into a load. The term usually refers to a type of radio-frequency power amplifier, some of which have output power measured in kilowatts, and are used in amateur radio...
s and splitters to increase the coupling points to a large electrical grid (whether a campus, a high-rise apartment or a community). These systems would typically require coaxial cable interconnection from a transmitter to the linear amplifiers. In the 1990s, LPB, Inc., possibly the largest manufacturer of these transmission systems, designed and supplied several extensive campus-based systems that included fiber-optic links between linear amplifiers to prevent heterodyne interference.
Because of their simple design and the fact that the transmitter doesn't need an external antenna, carrier current listening devices have found some use in the world of espionage
Espionage
Espionage or spying involves an individual obtaining information that is considered secret or confidential without the permission of the holder of the information. Espionage is inherently clandestine, lest the legitimate holder of the information change plans or take other countermeasures once it...
.
Student-run carrier current or cable cast stations
As with most other student-run stations, these stations often operate on sporadic schedules. Most of these stations are also supplemented by other broadcasting methods, such as LPFM, closed circuitClosed-circuit radio
A closed-circuit radio is a radio that emits over a very small range, typically a college campus. This system can be achieved from two ways:*By tying into the PA System*By using existing power lines, telephones lines, pipes, etc. to transmit a carrier current...
, and streaming audio. Many carrier current stations have been, and continue to be, replaced by these technologies as well. Though legal, these stations are not licensed by the FCC
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...
and their call letters
Call sign
In broadcasting and radio communications, a call sign is a unique designation for a transmitting station. In North America they are used as names for broadcasting stations...
are entirely self-styled.
Existing stations
- Bulls Radio 1620 - University of South FloridaUniversity of South FloridaThe University of South Florida, also known as USF, is a member institution of the State University System of Florida, one of the state's three flagship universities for public research, and is located in Tampa, Florida, USA...
, also heard on licensed WMNFWMNFWMNF is a non-commercial, community radio station operating in the city of Tampa in the U.S. state of Florida that broadcasts at the FM frequency of 88.5 MHz and streaming live...
-HD2HD RadioHD Radio, which originally stood for "Hybrid Digital", is the trademark for iBiquity's in-band on-channel digital radio technology used by AM and FM radio stations to transmit audio and data via a digital signal in conjunction with their analog signals... - KAMP-1570 at the University of ArizonaUniversity of ArizonaThe University of Arizona is a land-grant and space-grant public institution of higher education and research located in Tucson, Arizona, United States. The University of Arizona was the first university in the state of Arizona, founded in 1885...
- KANM-1580 at Texas A&M UniversityTexas A&M UniversityTexas A&M University is a coeducational public research university located in College Station, Texas . It is the flagship institution of the Texas A&M University System. The sixth-largest university in the United States, A&M's enrollment for Fall 2011 was over 50,000 for the first time in school...
- KASR-1330 Arizona State UniversityArizona State UniversityArizona State University is a public research university located in the Phoenix Metropolitan Area of the State of Arizona...
- KDUP-1580 at University of Portland, (Portland, Oregon) http://kdup.up.edu/
- KCIZ 1650 at Mora High School, Mora, MinnesotaMora, MinnesotaMora is a city in and the county seat of Kanabec County in the central part of the U.S. state of Minnesota. It is located at the junction of Minnesota State Highways 23 and 65. The population was 3,571 at the 2010 census.-History:...
- KJACK 1680 - Northern Arizona UniversityNorthern Arizona UniversityNorthern Arizona University is a public university located in Flagstaff, Arizona, United States. It is accredited by the North Central Association of Colleges and Schools, and has 39 satellite campuses in the state of Arizona. The university offers both undergraduate and graduate degrees.As of...
- KLBC-1610 at Long Beach City CollegeLong Beach City CollegeLong Beach City College, established in 1927, is a community college located in Long Beach, California. It is divided into two campuses. The Liberal Arts Campus, known as LAC, is located in the residential community of the Lakewood Village section of Long Beach, on Carson Street west of Clark Avenue...
- KMSC-1500KMSC (AM)KMSC is a student run unlicensed college radio station located on the campus of Minnesota State University Moorhead. The station, branded as Dragon Radio, airs on AM 1500.KMSC has been in existence in one form or another since the 1950s...
at Minnesota State University MoorheadMinnesota State University MoorheadMinnesota State University Moorhead is a four-year, public university located in Moorhead, Minnesota. The school has an enrollment of nearly 7,500 students and 337 full-time faculty members. MSUM is a part of the Minnesota State Colleges and Universities system... - KRFH at Humboldt State UniversityHumboldt State UniversityHumboldt State University is the northernmost campus of the California State University system, located in Arcata within Humboldt County, California, USA. The main campus, nestled at the edge of a coast redwood forest, is situated on Preston hill overlooking Arcata and with commanding views of...
- KSSUKSSU (AM)KSSU is an unlicensed, carrier current AM radio station on the campus of California State University, Sacramento broadcasting at 1580 AM and via streaming audio on the internet.- History :KSSU was started in 1989, but was originally known as "The Edge"...
1580 AM at California State University, SacramentoCalifornia State University, SacramentoCalifornia State University, Sacramento, popularly known as Sacramento State, is a public university located in the city of Sacramento, California. It is part of the California State University system... - KUR-1670/88.3 at Kutztown University
- KUTE-1620 University of UtahUniversity of UtahThe University of Utah, also known as the U or the U of U, is a public, coeducational research university in Salt Lake City, Utah, United States. The university was established in 1850 as the University of Deseret by the General Assembly of the provisional State of Deseret, making it Utah's oldest...
- Radio SNHU 1620 at Southern New Hampshire UniversitySouthern New Hampshire UniversitySouthern New Hampshire University, also known as SNHU, is a private university in Manchester and Hooksett, New Hampshire. The university is accredited by the Commission on Institutions of Higher Education of the New England Association of Schools and Colleges, and also has numerous specialized...
- WALT-1610 at Davidson CollegeDavidson CollegeDavidson College is a private liberal arts college in Davidson, North Carolina. The college has graduated 23 Rhodes Scholars and is consistently ranked in the top ten liberal arts colleges in the country by U.S. News and World Report magazine, although it has recently dropped to 11th in U.S. News...
- WAUG 97.9 FM cable cast at Augustana CollegeAugustana CollegeAugustana College may refer to:*Augustana College *Augustana College *Augustana University College, Alberta...
- WERW 1570 AMWERWWERW is a student-run radio station at Syracuse University that broadcasts on the Web. The station programs an eclectic format similar to many other college radio stations in the United States of America, with blocks of programs featuring underground rock music, world music, folk music, occasional...
at Syracuse UniversitySyracuse UniversitySyracuse University is a private research university located in Syracuse, New York, United States. Its roots can be traced back to Genesee Wesleyan Seminary, founded by the Methodist Episcopal Church in 1832, which also later founded Genesee College... - WEXPWEXP (La Salle University)WEXP is a Philadelphia college radio station with a freeform radio format. It airs live on 1600 AM in Philadelphia and online.- History :WEXP opened its doors at La Salle University in 1972. Initially, the radio station could only be heard inside the Student Union building, and the start-up price...
at La Salle UniversityLa Salle UniversityLa Salle University is a private, co-educational, Roman Catholic university located in Philadelphia, Pennsylvania, U.S. Named for St. Jean-Baptiste de La Salle, the school was founded in 1863 by the Institute of the Brothers of the Christian Schools. As of 2008 the school has approximately 7,554... - WFVS 530 AM and recently LPFM at 100.5 at Fort Valley State UniversityFort Valley State UniversityFort Valley State University is a historically black university located in Fort Valley, Georgia. It is also a unit of the University System of Georgia and a member school of the Thurgood Marshall Scholarship Fund...
in Fort Valley, GeorgiaFort Valley, GeorgiaFort Valley is a city in and the county seat of Peach County, Georgia, United States. As of the 2010 census, the city had a population of 9,815.Fort Valley is the corporate headquarters of the Blue Bird Corporation, a large manufacturer of buses...
(fiber-optic linked carrier current system) - The WIREThe WIREthe WIRE is the student-run College radio station at the University of Oklahoma, broadcasting in a freeform format. The WIRE serves the University of Oklahoma and surrounding communities, and is staffed by student DJs. The WIRE broadcasts at 1710 kHz AM in Norman, Oklahoma...
- 1710 AM at the University of OklahomaUniversity of OklahomaThe University of Oklahoma is a coeducational public research university located in Norman, Oklahoma. Founded in 1890, it existed in Oklahoma Territory near Indian Territory for 17 years before the two became the state of Oklahoma. the university had 29,931 students enrolled, most located at its... - WMAX 540 at Hesser CollegeHesser CollegeHesser College is a for-profit college with several campuses in New Hampshire. It is owned by Kaplan, Inc. The college offers associate and bachelor degrees in the fields of early childhood education, criminal justice, general studies, business and various art programs. The college claims a...
in Manchester, New HampshireManchester, New HampshireManchester is the largest city in the U.S. state of New Hampshire, the tenth largest city in New England, and the largest city in northern New England, an area comprising the states of Maine, New Hampshire, and Vermont. It is in Hillsborough County along the banks of the Merrimack River, which... - Wolfpack Radio-1700 at the University of NevadaUniversity of Nevada, RenoThe University of Nevada, Reno , is a teaching and research university established in 1874 and located in Reno, Nevada, USA...
- WPPJ-670 Point Park College
- WPMD-1700 at Cerritos CollegeCerritos CollegeCerritos College is a public comprehensive community college founded in 1955 located in Norwalk, California. It was named after Rancho Los Cerritos, a ranch that served prominently in the region in the 19th century...
- WRHSWRHSWRHS is an FM radio station broadcasting on 89.7 MHz in Norridge, Illinois, in the Chicago metropolitan area. It is owned and operated by Ridgewood High School, and it broadcasts from the campus in Norridge, Illinois.-Christmas:...
89.7 FM at Ridgewood High SchoolRidgewood High School (Illinois)Ridgewood High School, or RHS, is a public four-year high school located in Norridge, Illinois, a western suburb of Chicago, Illinois, in the United States...
, Norridge, IllinoisNorridge, IllinoisNorridge is a village in Cook County, Illinois, United States. The population was 14,582 at the 2000 census. The current Mayor of Norridge is Ronald A. Oppedisano.The village is completely surrounded by Chicago and Harwood Heights.-Name origin:... - WRWX / WXMS 88.1 FM Harwood Heights, IllinoisHarwood Heights, IllinoisHarwood Heights is a village in Cook County, Illinois, United States. The population was 8,297 at the 2000 census. The current Mayor is Arlene Jezierny...
, at Ridgewood High SchoolRidgewood High School (Illinois)Ridgewood High School, or RHS, is a public four-year high school located in Norridge, Illinois, a western suburb of Chicago, Illinois, in the United States... - WSIN-1590 at Southern Connecticut State UniversitySouthern Connecticut State UniversitySouthern Connecticut State University is one of four state universities in Connecticut, and is located in the West Rock neighborhood of New Haven, Connecticut...
- WSLU-1620/100.1] at Saint Leo UniversitySaint Leo UniversitySaint Leo University is a private, non-profit, Roman Catholic liberal arts university established in 1889 and located in Saint Leo, Florida, 35 miles north of Tampa. The University is associated with the Holy Name Monastery, a Benedictine convent, and Saint Leo Abbey, a Benedictine monastery...
, St. Leo, FloridaSt. Leo, FloridaSt. Leo is a town in Pasco County, Florida, United States. It is a suburb included in the Tampa-St. Petersburg-Clearwater, Florida Metropolitan Statistical Area. The population was 595 at the 2000 census. As of 2006, the population recorded by the U.S. Census Bureau is 1,249.It is best known as... - KSUB at Seattle UniversitySeattle UniversitySeattle University is a Jesuit Catholic university located in the First Hill neighborhood of Seattle, Washington, USA.SU is the largest independent university in the Northwest US, with over 7,500 students enrolled in undergraduate and graduate programs within eight schools, and is one of 28 member...
in conjunction with 8 mW low-power broadcastingLow-power broadcastingLow-power broadcasting is electronic broadcasting at very low power and low cost, to a small community area.The terms "low-power broadcasting" and "micropower broadcasting" should not be used interchangeably, because the markets are not the same...
and Internet radioInternet radioInternet radio is an audio service transmitted via the Internet... - WTBUWTBUWTBU is a "Part 15" student-managed and -operated radio station at Boston University. This means it is not licensed by the FCC but operates legally under special "low power" rules...
640 AM/89.3 FM at Boston UniversityBoston UniversityBoston University is a private research university located in Boston, Massachusetts. With more than 4,000 faculty members and more than 31,000 students, Boston University is one of the largest private universities in the United States and one of Boston's largest employers... - WVYCWVYCWVYC is a college radio station licensed by the Federal Communications Commission to serve the community of York, Pennsylvania, USA. The station broadcasts from the Robert V. Iosue Student Union Building on the campus of York College of Pennsylvania in York...
640 AM at York College of PennsylvaniaYork College of PennsylvaniaYork College of Pennsylvania is a private, coeducational, 4-year college located in southcentral Pennsylvania. The school offers more than 50 baccalaureate majors in professional programs, the sciences, and humanities to its 4,600 undergraduate students...
, sister station to FCC-licensed WVYCWVYCWVYC is a college radio station licensed by the Federal Communications Commission to serve the community of York, Pennsylvania, USA. The station broadcasts from the Robert V. Iosue Student Union Building on the campus of York College of Pennsylvania in York...
FM 99.7, also on the Internet - Radio Laurier Macdonald 560 AM at Laurier Macdonald High SchoolLaurier Macdonald High SchoolLaurier Macdonald High School is an English-language public school in the east end of Montreal, Quebec, Canada. The school is named for Sir John A. Macdonald, the first Prime Minister of Canada and a Father of Confederation and Sir Wilfrid Laurier, the first French-Canadian Prime Minister of Canada...
in St. Leonard, Montreal, Quebec, Canada
Former stations
- CHRW-FMCHRW-FMCHRW-FM is a Canadian radio station, broadcasting at 94.9 FM in London, Ontario. It is licensed as a community-based campus radio station by the Canadian Radio-television and Telecommunications Commission...
at the University of Western OntarioUniversity of Western OntarioThe University of Western Ontario is a public research university located in London, Ontario, Canada. The university's main campus covers of land, with the Thames River cutting through the eastern portion of the main campus. Western administers its programs through 12 different faculties and...
started as a carrier current station at 610 kHz - K.C. AM at Colby CollegeColby CollegeColby College is a private liberal arts college located on Mayflower Hill in Waterville, Maine. Founded in 1813, it is the 12th-oldest independent liberal arts college in the United States...
, now WMHBWMHBWMHB, 89.7 FM Waterville, is the non-commercial College radio station of Colby College in Waterville, Maine, USA. WMHB is directed, managed, and staffed entirely by students. WMHB has been on air in one form or another since 1949... - KARL-AM at Carleton CollegeCarleton CollegeCarleton College is an independent non-sectarian, coeducational, liberal arts college in Northfield, Minnesota, USA. The college enrolls 1,958 undergraduate students, and employs 198 full-time faculty members. In 2012 U.S...
, now KRLXKRLXKRLX is a student-run, freeform radio format, non-commercial FM college radio station broadcasting from Northfield, Minnesota. Affiliated with Carleton College. The station's call sign was chosen to read "KaRL-ten," since X is the Roman numeral for ten. KRLX broadcasts with 100 watts of power at... - KAL at University of California, BerkeleyUniversity of California, BerkeleyThe University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
- now KALXKALXKALX is a freeform FM radio station that broadcasts from the University of California, Berkeley in Berkeley, California. KALX, a community- and student-run radio station licensed to the University of California, Berkeley, broadcasts in stereo with 500 watts of power... - KCC at Chabot CollegeChabot CollegeChabot College is a community college located in Hayward, California.-Campus:The campus has a 200-seat theatre, a 1,432-seat performing arts center, a full-size planetarium, four major athletic fields, an HD television studio, and an Olympic-class swimming pool.-History:Chabot College was the first...
, Hayward, CaliforniaHayward, CaliforniaHayward is a city located in the East Bay in Alameda County, California. With a population of 144,186, Hayward is the sixth largest city in the San Francisco Bay Area and the third largest in Alameda County. Hayward was ranked as the 37th most populous municipality in California. It is included in...
- now KCRHKCRHKCRH is a radio station in Hayward, California, serving the Bay Area, primarily the East Bay. The station is owned by Chabot College and operated by students in its Mass Communications department.- Station overview :...
89.9 - KCWS-AM at Central Washington State College - now KCWU-FM
- KDVS, originally KCDKDVSKDVS is an American student and community radio station based in Davis, California. Featuring a freeform programming format, the station is owned by Regents of the University of California...
at University of California, DavisUniversity of California, DavisThe University of California, Davis is a public teaching and research university established in 1905 and located in Davis, California, USA. Spanning over , the campus is the largest within the University of California system and third largest by enrollment... - KFRH at Washington University in St. LouisWashington University in St. LouisWashington University in St. Louis is a private research university located in suburban St. Louis, Missouri. Founded in 1853, and named for George Washington, the university has students and faculty from all fifty U.S. states and more than 110 nations...
- now KWURKWURKWUR is a College radio in St. Louis, Missouri located at 90.3 MHz FM. KWUR was founded on July 4, 1976 at Washington University in St. Louis, and represents one of the last remaining independent and fully student managed radio station in the United States....
-FM - KMPS-AM at University of Alaska FairbanksUniversity of Alaska FairbanksThe University of Alaska Fairbanks, located in Fairbanks, Alaska, USA, is the flagship campus of the University of Alaska System, and is abbreviated as Alaska or UAF....
- now KSUAKSUAKSUA is a College radio station broadcasting a Non-commercial educational format. Licensed to Fairbanks, Alaska, USA, , the station serves the Alaska Interior area...
-FM - KNAB at Chapman UniversityChapman UniversityChapman University is a private, non-profit university located in Orange, California affiliated with the Christian Church . Known for its blend of liberal arts and professional programs, Chapman University encompasses seven schools and colleges: Lawrence and Kristina Dodge College of Film and Media...
, Orange, CaliforniaOrange, CaliforniaSouthern California is well-known for year-round pleasant weather: - On average, the warmest month is August. - The highest recorded temperature was in 1985. - On average, the coolest month is December. - The lowest recorded temperature was in 1950...
- ceased carrier current in 1991, now internet-only station ChapmanRadio.com - KOWL at Rice UniversityRice UniversityWilliam Marsh Rice University, commonly referred to as Rice University or Rice, is a private research university located on a heavily wooded campus in Houston, Texas, United States...
- now Rice Radio - KSU at Stanford UniversityStanford UniversityThe Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
– now KZSUKZSUKZSU is a freeform FM radio station broadcasting from the campus of Stanford University in Stanford, California, USA.KZSU broadcasts in stereo at 90.1 MHz FM with an effective radiated power of 500 watts. The station is owned by the Trustees of Stanford University and is governed by a Board of...
-FM - KUOK at the University of KansasUniversity of KansasThe University of Kansas is a public research university and the largest university in the state of Kansas. KU campuses are located in Lawrence, Wichita, Overland Park, and Kansas City, Kansas with the main campus being located in Lawrence on Mount Oread, the highest point in Lawrence. The...
- now KJHKKJHKKJHK 90.7 FM is a campus radio station, located in Lawrence, Kansas at the University of Kansas. On December 3, 1994, the station became one of the first radio stations to broadcast a live and continuous stream over internet radio. It currently broadcasts at 2600 watts, with a broadcast area... - KSWCKSWCKSWC is a radio station broadcasting a CHR format. Licensed to Winfield, Kansas, USA. The station is owned by Southwestern College....
at Southwestern CollegeSouthwestern College (Kansas)Southwestern College is a four-year private college affiliated with the United Methodist Church located in Winfield, Kansas, United States. It was founded in 1885 and graduated its first class in 1889. In addition to its campus programs, it offers online programs.-Academics:The main campus is a...
in Winfield, KansasWinfield, KansasWinfield is a city situated along the Walnut River in the west-central part of Cowley County, located in South Central Kansas, in the Central United States. As of the 2010 census, the city population was 12,301...
- now at 100.3 FM - WBMB at Baruch CollegeBaruch CollegeBernard M. Baruch College, more commonly known as Baruch College, is a constituent college of the City University of New York, located in the Flatiron district of Manhattan, New York City. With an acceptance rate of just 23%, Baruch is among the most competitive and diverse colleges in the nation...
, CUNY started as a carrier current station at 590AM - WCAR 550AM at the University of North Carolina at Chapel HillUniversity of North Carolina at Chapel HillThe University of North Carolina at Chapel Hill is a public research university located in Chapel Hill, North Carolina, United States...
- now WXYCWXYCWXYC is a radio station broadcasting a college radio format. Licensed to Chapel Hill, North Carolina, USA, the station is run by students of the University of North Carolina at Chapel Hill. The station is currently owned by Student Educational Broadcasting...
-FM 89.3 - WDBS 560-AM at Duke UniversityDuke UniversityDuke University is a private research university located in Durham, North Carolina, United States. Founded by Methodists and Quakers in the present day town of Trinity in 1838, the school moved to Durham in 1892. In 1924, tobacco industrialist James B...
- now WXDU-FMWXDU-FMWXDU is a non-commercial campus radio station broadcasting a college radio format. Licensed to Durham, North Carolina, USA, the station serves the North Carolina college area...
88.7 - WFAL 1610AM at Bowling Green State UniversityBowling Green State UniversityBowling Green State University, often referred to as Bowling Green or BGSU, is a public, coeducational research university located in Bowling Green, Ohio, United States. The institution was granted a charter in 1910 by the State of Ohio as part of the Lowry Bill, which also established Kent State...
- WHAT 530AM at Johns Hopkins UniversityJohns Hopkins UniversityThe Johns Hopkins University, commonly referred to as Johns Hopkins, JHU, or simply Hopkins, is a private research university based in Baltimore, Maryland, United States...
, later WHSR and now WJHUWJHUWJHU is a radio station based in Baltimore, Maryland. The Johns Hopkins University owns the station, a Community radio station with student volunteers, who are mainly on-air deejays and other program hosts... - WHEN 640 AM at the University of DelawareUniversity of DelawareThe university is organized into seven colleges:* College of Agriculture and Natural Resources* College of Arts and Sciences* Alfred Lerner College of Business and Economics* College of Earth, Ocean and Environment* College of Education and Human Development...
- WHENWIUSWIUS is a 120 watt student operated campus radio station in Macomb, Illinois, in west-central Illinois. The station is run by Western Illinois University and is authorized by the Federal Communications Commission....
at Western Illinois UniversityWestern Illinois UniversityWestern Illinois University is a public university founded in 1899 as Western Illinois State Normal School. Like many similar institutions of the time, Western Illinois State Normal School focused on teacher training for its relatively small body of students. As the normal school grew, it became...
- now WIUSWIUSWIUS is a 120 watt student operated campus radio station in Macomb, Illinois, in west-central Illinois. The station is run by Western Illinois University and is authorized by the Federal Communications Commission....
-FM - WJJX 640AM at the University of MichiganUniversity of MichiganThe University of Michigan is a public research university located in Ann Arbor, Michigan in the United States. It is the state's oldest university and the flagship campus of the University of Michigan...
from 1952 to 1987, predecessor to (and previously using the call letters) WCBNWCBNWCBN-FM is the student-run radio station of the University of Michigan. Its format is primarily freeform. It broadcasts at 88.3 MHz FM in Ann Arbor, Michigan.- History :...
now on FM 88.3 - WJPZWJPZWJPZ-FM is a college radio station owned and operated entirely by students at Syracuse University in New York. It broadcasts at 89.1 FM at an effective radiated power of 100 watts and can be heard throughout Syracuse, the rest of Onondaga County, and beyond to the north and east. WJPZ programs a...
at Syracuse UniversitySyracuse UniversitySyracuse University is a private research university located in Syracuse, New York, United States. Its roots can be traced back to Genesee Wesleyan Seminary, founded by the Methodist Episcopal Church in 1832, which also later founded Genesee College...
, now 89.1 FM - WKC at Knox College - now WVKCWVKCWVKC is a 1,000-watt radio station in Galesburg, Illinois, in west-central Illinois. Knox College is the station licensee, authorized by the Federal Communications Commission....
-FM - WKDU-FM 91.7WKDUWKDU is an award winning non-commercial college radio station located in Philadelphia, USA, broadcasting on 91.7 FM. It is owned and operated by Drexel University students, with several Drexel alumni among its on-air staff. It is the only free-format non-commercial FM station in Philadelphia...
, the student-run radio station of Drexel UniversityDrexel UniversityDrexel University is a private research university with the main campus located in Philadelphia, Pennsylvania, USA. It was founded in 1891 by Anthony J. Drexel, a noted financier and philanthropist. Drexel offers 70 full-time undergraduate programs and accelerated degrees...
formally WMAX (1958) - WKDT 89.3 FM, the cadet radio station, United States Military AcademyUnited States Military AcademyThe United States Military Academy at West Point is a four-year coeducational federal service academy located at West Point, New York. The academy sits on scenic high ground overlooking the Hudson River, north of New York City...
, West Point, New YorkWest Point, New YorkWest Point is a federal military reservation established by President of the United States Thomas Jefferson in 1802. It is a census-designated place located in Town of Highlands in Orange County, New York, United States. The population was 7,138 at the 2000 census... - WLKR AM Lake Superior State UniversityLake Superior State UniversityLake Superior State University is a small public university in Sault Ste. Marie, Michigan. It is Michigan's smallest public university with an enrollment around 3,000 students. Due to its proximity to the border, notably the twin city of Sault Ste...
, Sault Ste. Marie, MichiganSault Ste. Marie, MichiganSault Ste. Marie is a city in and the county seat of Chippewa County in the U.S. state of Michigan. It is in the north-eastern end of Michigan's Upper Peninsula, on the Canadian border, separated from its twin city of Sault Ste. Marie, Ontario, by the St. Marys River...
- Now WLSOWLSOWLSO is a radio station in Sault Ste. Marie, Michigan, United States, broadcasting at 90.1 on the FM dial. It is the college radio station of the city's Lake Superior State University....
90.1 FM "The Sounds of Lake State" - WMTUWMTUWMTU-FM 91.9 is the student-run campus radio station at Michigan Technological University. It is located in the basement of Wadsworth Hall in Houghton, Michigan, and operates 24 hours a day, 7 days a week, with exceptions for holidays and breaks from school...
-FM started as a carrier-current AM station. - WMUC-FMWMUC-FMWMUC-FM is the student-run non-commercial radio station licensed to the University of Maryland in College Park, Maryland, broadcasting at 10 watts...
started in 1937 on 650 AM. - WNYU on 800 AM in New York UniversityNew York UniversityNew York University is a private, nonsectarian research university based in New York City. NYU's main campus is situated in the Greenwich Village section of Manhattan...
's dorms at its Lower ManhattanLower ManhattanLower Manhattan is the southernmost part of the island of Manhattan, the main island and center of business and government of the City of New York...
campus. - WOCR-650 A "pirate" carrier current station in Ocean City, MarylandOcean City, MarylandOcean City, sometimes known as OC, or OCMD, is an Atlantic Ocean resort town in Worcester County, Maryland, United States. Ocean City is widely known in the Mid-Atlantic region of the United States and is a frequent destination for vacationers in that area...
in 1973 - WOLF at North Carolina State UniversityNorth Carolina State UniversityNorth Carolina State University at Raleigh is a public, coeducational, extensive research university located in Raleigh, North Carolina, United States. Commonly known as NC State, the university is part of the University of North Carolina system and is a land, sea, and space grant institution...
in Raleigh, North CarolinaRaleigh, North CarolinaRaleigh is the capital and the second largest city in the state of North Carolina as well as the seat of Wake County. Raleigh is known as the "City of Oaks" for its many oak trees. According to the U.S. Census Bureau, the city's 2010 population was 403,892, over an area of , making Raleigh...
- now WKNCWKNCWKNC-FM , North Carolina State University's student-run radio station, is a College radio station in the United States. Broadcasting with an effective radiated power of 25,000 watts, its signal covers much of the Research Triangle and outlying areas. The station is entirely student-run, from the... - WPSM at Penn State's Mckeesport campus (now Penn State Greater Allegheny) - now an internet station WMKP
- WQAD/WFQR/WIN/WIUSWIUXWIUX-LP is a student-operated low power FM college radio station in Bloomington, Indiana, in southern Indiana. The station licensee, Indiana University Student Broadcasting is authorized by the Federal Communications Commission.-Operation:...
at Indiana UniversityIndiana University BloomingtonIndiana University Bloomington is a public research university located in Bloomington, Indiana, in the United States. IU Bloomington is the flagship campus of the Indiana University system. Being the flagship campus, IU Bloomington is often referred to simply as IU or Indiana...
- now WIUXWIUXWIUX-LP is a student-operated low power FM college radio station in Bloomington, Indiana, in southern Indiana. The station licensee, Indiana University Student Broadcasting is authorized by the Federal Communications Commission.-Operation:...
-LP - WRAFWHRWWHRW is Binghamton University's non-profit, student run, free format radio station. Licensed to Binghamton, New York, USA, the station serves the New York college area. The station is currently owned by Binghamton University. The station has operational facilities in and on top of the Glenn G...
on 590 AM at Binghamton UniversityBinghamton UniversityBinghamton University, also formally called State University of New York at Binghamton, , is a public research university in the State of New York. The University is one of the four university centers in the State University of New York system...
- now WHRWWHRWWHRW is Binghamton University's non-profit, student run, free format radio station. Licensed to Binghamton, New York, USA, the station serves the New York college area. The station is currently owned by Binghamton University. The station has operational facilities in and on top of the Glenn G... - WRLC-AMWVPHWVPH is Piscataway, New Jersey's community and student-run radio station.It is a broadcasting agreement between the former WRLC AM station from Rutgers, Livingston College and WVPH-FM from Piscataway High School. The two institutions combined forces in 1977 to create an educational opportunity and...
on 1110 and 1150 AM at Rutgers UniversityRutgers UniversityRutgers, The State University of New Jersey , is the largest institution for higher education in New Jersey, United States. It was originally chartered as Queen's College in 1766. It is the eighth-oldest college in the United States and one of the nine Colonial colleges founded before the American...
, now WVPH-FM - WRCKWRSKWSRU represents the call letters of two different organizations at Slippery Rock University of Pennsylvania, both the student run television station, WSRU-TV, as well as the student run FM radio station, WSRU-FM .-WSRU-TV:...
at Slippery Rock University - now WRSKWRSKWSRU represents the call letters of two different organizations at Slippery Rock University of Pennsylvania, both the student run television station, WSRU-TV, as well as the student run FM radio station, WSRU-FM .-WSRU-TV:...
-FM - WRCR-AM Rockford CollegeRockford CollegeRockford College is a private American liberal arts college in Rockford, Illinois. It was founded in 1847 as Rockford Female Seminary and changed its name in 1892. The college is known as the alma mater of Nobel Peace Prize winner Jane Addams, who was a member of the class of...
- WRCTWRCTWRCT is a non-commercial freeform radio station based in Pittsburgh, Pennsylvania. The station, which is hosted in the basement of Carnegie Mellon's University Center, is run by students, staff, faculty, and community members. WRCT broadcasts on 88.3 MHz with an ERP of 1.75 kW, from atop...
on 900 AM at Carnegie Mellon UniversityCarnegie Mellon UniversityCarnegie Mellon University is a private research university in Pittsburgh, Pennsylvania, United States....
- now WRCT-FM - WRUR-AM 1090 at University of RochesterUniversity of RochesterThe University of Rochester is a private, nonsectarian, research university in Rochester, New York, United States. The university grants undergraduate and graduate degrees, including doctoral and professional degrees. The university has six schools and various interdisciplinary programs.The...
in Rochester, New YorkRochester, New YorkRochester is a city in Monroe County, New York, south of Lake Ontario in the United States. Known as The World's Image Centre, it was also once known as The Flour City, and more recently as The Flower City...
- now WRUR-FM see also Campus RadioCampus radioCampus radio is a type of radio station that is run by the students of a college, university or other educational institution. Programming may be exclusively by students, or may include programmers from the wider community in which the radio station is based... - WSOE on 1200 AM at the Milwaukee School of EngineeringMilwaukee School of EngineeringThe Milwaukee School of Engineering is a private university located in downtown Milwaukee, Wisconsin. MSOE is best known for its applications-oriented curriculum, close association with business and industry, and extremely high placement rate...
in Milwaukee, WisconsinWisconsinWisconsin is a U.S. state located in the north-central United States and is part of the Midwest. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. Wisconsin's capital is...
- now WMSEWMSEWMSE is a non-commercial radio station in Milwaukee, Wisconsin, playing a wide-ranging eclectic music format run by volunteer DJ's. The station is part of the Milwaukee School of Engineering .-Early history of MSOE stations:...
on 91.7 FM see also Campus RadioCampus radioCampus radio is a type of radio station that is run by the students of a college, university or other educational institution. Programming may be exclusively by students, or may include programmers from the wider community in which the radio station is based... - WUFI-540AM at Florida International UniversityFlorida International UniversityFlorida International University is an American public research university in metropolitan Miami, Florida, in the United States, with its main campus in University Park...
now WRGP 88.1 & 95.3 FM - WUVT 640 AM at Virginia Tech
- WVAU on 610 AM at American UniversityAmerican UniversityAmerican University is a private, Methodist, liberal arts, and research university in Washington, D.C. The university was chartered by an Act of Congress on December 5, 1892 as "The American University", which was approved by President Benjamin Harrison on February 24, 1893...
(station is still present, but they no longer broadcast carrier current) - WVBU on 640 AM at Bucknell UniversityBucknell UniversityBucknell University is a private liberal arts university located alongside the West Branch Susquehanna River in the rolling countryside of Central Pennsylvania in the town of Lewisburg, 30 miles southeast of Williamsport and 60 miles north of Harrisburg. The university consists of the College of...
later licensed to 90.5 MHz FM, carrier current turned off several years later - WVOFWVOFWVOF is the student-run college radio station at Fairfield University in Fairfield, Connecticut. As of August 2008, the station has been a partner with Connecticut Public Radio and carries Connecticut Public Radio and NPR programming.-History:...
on 620 AM at Fairfield UniversityFairfield UniversityFairfield University is a private, co-educational undergraduate and master's level teaching-oriented university located in Fairfield, Connecticut, in the New England region of the United States. It was founded by the Society of Jesus in 1942, and today is one of 28 member institutions of the... - WXOUWXOUWXOU is the on-campus radio station located at Oakland University in Rochester, Michigan, USA. The station can be heard at 88.3 FM and streaming on the station's website www.wxou.org. The broadcast studio and administrative offices are located in the Oakland Center building on the lower level....
88.3 FM at Oakland UniversityOakland UniversityOakland University is a public university co-founded by Matilda Dodge Wilson and John A. Hannah whose campus is located in central Oakland County, Michigan, United States in the cities of Auburn Hills and Rochester Hills. It is the only major research university in Oakland County, from which OU...
in Rochester Hills, MichiganRochester Hills, MichiganRochester Hills is an affluent city in northeast Oakland County of the U.S. state of Michigan. As of the 2010 census, the city had a total population of 70,995. The city of Rochester is bounded on the north, south, and west by Rochester Hills...
(Licensed to Auburn Hills, MichiganAuburn Hills, MichiganAuburn Hills is a city in Metro Detroit, Oakland County, in the U.S. state of Michigan. The population was 21,412 at the 2010 census. The city was formed in 1983 when Pontiac Township became the City of Auburn Hills.-Economy:...
) - WXPNWXPNWXPN is a non-commercial, public radio station operated by the University of Pennsylvania in Philadelphia that broadcasts a music radio format called adult album alternative , along with many other format shows supported all with an indie slant...
and WQHS-730WQHS RadioWQHS is the only wholly student-operated college radio station at the University of Pennsylvania. WXPN was the University's principal student radio station until 1975, with WQHS as an AM-based training ground for DJs. After 1975, WQHS became the official student radio station of the University,...
at the University of PennsylvaniaUniversity of PennsylvaniaThe University of Pennsylvania is a private, Ivy League university located in Philadelphia, Pennsylvania, United States. Penn is the fourth-oldest institution of higher education in the United States,Penn is the fourth-oldest using the founding dates claimed by each institution... - WRIUWRIUWRIU is a non-commercial radio station broadcasting a college radio format. Licensed to Kingston, Rhode Island, USA, the station serves the greater Rhode Island area. The station is currently owned by University of Rhode Island...
Studio B, now only online, at University of Rhode IslandUniversity of Rhode IslandThe University of Rhode Island is the principal public research university in the U.S. state of Rhode Island. Its main campus is located in Kingston. Additional campuses include the Feinstein Campus in Providence, the Narragansett Bay Campus in Narragansett, and the W. Alton Jones Campus in West...
and licensed to Kingston, Rhode IslandKingston, Rhode IslandKingston is a village and a census-designated place in the town of South Kingstown, Rhode Island, United States, and the site of the main campus of the University of Rhode Island. Much of the village center is listed on the National Register of Historic Places as Kingston Village Historic... - WCURWCUR91.7 WCUR FM The Curve, also known as West Chester University Radio, is a college radio station that broadcasts in the Philadelphia area via a transmitter that covers a 5-mile radius around West Chester University in West Chester, Pennsylvania. WCUR offers a wide variety of music, news, sports,...
as WSCS 640 AM, and WCUR 680 AM at West Chester University in West Chester, PennsylvaniaWest Chester, PennsylvaniaThe Borough of West Chester is the county seat of Chester County, Pennsylvania, United States. The population was 18,461 at the 2010 census.Valley Forge, the Brandywine Battlefield, Longwood Gardens, Marsh Creek State Park, and other historical attractions are near West Chester...
, but has since migrated to 91.7 FM, as well as online at wcur.org - WSGR (South Green Radio) at Ohio UniversityOhio UniversityOhio University is a public university located in the Midwestern United States in Athens, Ohio, situated on an campus...
in Athens, OhioAthens, OhioAthens is the largest city in, and the county seat of, Athens County, Ohio, United States. It is located along the Hocking River in the southeastern part of Ohio. A historic college town, Athens is home to Ohio University and is the principal city of the Athens, Ohio Micropolitan Statistical Area. ...
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See also
- Power line communicationPower line communicationPower line communication or power line carrier , also known as power line digital subscriber line , mains communication, power line telecom , power line networking , or broadband over power lines are systems for carrying data on a conductor also used for electric power transmission.A wide range...
- Leaky feederLeaky feederA leaky feeder is a communications system used in underground mining and other tunnel environments. It consists of a coaxial cable run along drivages which emits and receives radio waves. The cable is "leaky" in that it has gaps or slots in its outer conductor to allow signal to leak into or out of...
- Carrier Current Broadcasting Theory by LPB
- Carrier Current AM Broadcasting