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74-750: Most of the stations were originally the medium wave services of Independent Local Radio stations. For example, "Classic Gold 1359" in Coventry was originally part of Mercia Sound and was a full local service. In the 1980s, FM/AM stations split (in this case to Mercia FM and Xtra AM ), before the station was bought by GWR radio in 1993, and the AM station rebranded to "Classic Gold". In 1998, Classic Gold in Northampton legally rebranded to Classic Gold 1557 Northamptonshire. The stations were sold to UBC in two tranches in 2000 and 2002; however, in 2007 they came back under

148-435: A World Administrative Radio Conference (WARC-79) adopted "Radio Regulation No. 480", which stated that "In Region 2, the use of the band 1605-1705 kHz by stations of the broadcasting service shall be subject to a plan to be established by a regional administrative radio conference..." As a consequence, on June 8, 1988 an ITU-sponsored conference held at Rio de Janeiro, Brazil adopted provisions, effective July 1, 1990, to extend

222-563: A skywave . The medium-wave transmitter at Berlin-Britz for transmitting RIAS used a cross dipole mounted on five 30.5-metre-high guyed masts to transmit the skywave to the ionosphere at nighttime. Because at these frequencies atmospheric noise is far above the receiver signal-to-noise ratio , inefficient antennas much smaller than a wavelength can be used for receiving. For reception at frequencies below 1.6 MHz, which includes long and medium waves, loop antennas are popular because of their ability to reject locally generated noise. By far

296-740: A few specially licensed AM broadcasting stations. These channels are called clear channels , and they are required to broadcast at higher powers of 10 to 50 kW. Initially, broadcasting in the United States was restricted to two wavelengths: "entertainment" was broadcast at 360 meters (833 kHz), with stations required to switch to 485 meters (619 kHz) when broadcasting weather forecasts, crop price reports and other government reports. This arrangement had numerous practical difficulties. Early transmitters were technically crude and virtually impossible to set accurately on their intended frequency and if (as frequently happened) two (or more) stations in

370-514: A lower one for omnidirectional and a higher one for directional radiation with minima in certain directions. The power limit can also be depending on daytime and it is possible that a station may not operate at nighttime, because it would then produce too much interference. Other countries may only operate low-powered transmitters on the same frequency, again subject to agreement. International medium wave broadcasting in Europe has decreased markedly with

444-404: A poor vertical radiation pattern, and 195 electrical degrees (about 400 millivolts per meter using one kilowatt at one kilometre) is generally considered ideal in these cases. Mast antennas are usually series-excited (base driven); the feedline is attached to the mast at the base. The base of the antenna is at high electrical potential and must be supported on a ceramic insulator to isolate it from

518-436: A quarter- wavelength (about 310 millivolts per meter using one kilowatt at one kilometre) to 5/8 wavelength (225 electrical degrees; about 440 millivolts per meter using one kilowatt at one kilometre), while high power stations mostly use half-wavelength to 5/9 wavelength. The usage of masts taller than 5/9 wavelength (200 electrical degrees; about 410 millivolts per meter using one kilowatt at one kilometre) with high power gives

592-420: A vertical radiator wire. A popular choice for lower-powered stations is the umbrella antenna , which needs only one mast one-tenth wavelength or less in height. This antenna uses a single mast insulated from ground and fed at the lower end against ground. At the top of the mast, radial top-load wires are connected (usually about six) which slope downwards at an angle of 40–45 degrees as far as about one-third of

666-459: Is a part of the medium frequency (MF) radio band used mainly for AM radio broadcasting . The spectrum provides about 120 channels with more limited sound quality than FM stations on the FM broadcast band . During the daytime, reception is usually limited to more local stations, though this is dependent on the signal conditions and quality of radio receiver used. Improved signal propagation at night allows

740-477: Is adequate for talk and news but not for high-fidelity music. However, many stations use audio bandwidths up 10 kHz, which is not hi-fi but sufficient for casual listening. In the UK, until 2024 most stations used a bandwidth of 6.3 kHz. However in 2024, Ofcom expanded the allowed bandwidth to 9khz, giving a noticeable improvement in quality. With AM, it largely depends on the frequency filters of each receiver how

814-433: Is available, (however digital radio still has coverage issues in many parts of Europe). Many countries in Europe have switched off or limited their MW transmitters since the 2010s. The term is a historic one, dating from the early 20th century, when the radio spectrum was divided on the basis of the wavelength of the waves into long wave (LW), medium wave, and short wave (SW) radio bands. For Europe, Africa and Asia

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888-638: Is possible and is or was offered by some stations in the U.S., Canada, Mexico, the Dominican Republic, Paraguay, Australia, The Philippines, Japan, South Korea, South Africa, Italy and France. However, there have been multiple standards for AM stereo . C-QUAM is the official standard in the United States as well as other countries, but receivers that implement the technology are no longer readily available to consumers. Used receivers with AM Stereo can be found. Names such as "FM/AM Stereo" or "AM & FM Stereo" can be misleading and usually do not signify that

962-433: Is primarily only used by low-power stations; it is the preferred range for services with automated traffic, weather, and tourist information. The channel steps of 9 and 10 kHz require limiting the audio bandwidth to 9 and 10 kHz (at maximum without causing interference; ±4.5 kHz (9 kHz) and ±5 kHz (10 kHz) on each two sidebands) because the audio spectrum is transmitted twice on each side band . This

1036-507: Is that the two stations must remain under common ownership, > although an exception was made in the case of KYHN in Fort Smith, Arkansas, when the FCC approved its separate ownership, on the grounds that "Capstar's donation of the facility to MMTC, which planned to use KYHN to train women and minority group members in broadcasting and broadcast management, advanced the diversity goals set forth in

1110-510: Is the ITU-approved system for use outside North America and U.S. territories . Some HD Radio receivers also support C-QUAM AM stereo, although this feature is usually not advertised by the manufacturer. For broadcasting, mast radiators are the most common type of antenna used, consisting of a steel lattice guyed mast in which the mast structure itself is used as the antenna. Stations broadcasting with low power can use masts with heights of

1184-577: Is warranted to permit the licensing of a station that could provide full-time local emergency radio service to Rockland County residents who would be at great risk in the event of a radiological emergency at the Indian Point facility". A 2006 accounting by Radio World reported that, out of 4,758 licensed U.S. AM stations, 56 were now operating on the expanded band. The expanded band frequencies have also become popular for use by hobbyist microbroadcasting transmissions (which don't require licenses) due to

1258-760: The AM expanded band , refers to the broadcast station frequency assignments immediately above the earlier upper limits of 1600 kHz in International Telecommunication Union (ITU) Region 2 (the Americas), and 1602 kHz in ITU Regions 1 (Europe, northern Asia and Africa) and 3 (southern Asia and Oceania). In Region 2, this consists of ten additional frequencies, spaced 10 kHz apart, and running from 1610 kHz to 1700 kHz. In Regions 1 and 3, where frequency assignments are spaced 9 kHz apart,

1332-801: The Beverage antenna ) and the ferrite sleeve loop antenna. ELF 3 Hz/100 Mm 30 Hz/10 Mm SLF 30 Hz/10 Mm 300 Hz/1 Mm ULF 300 Hz/1 Mm 3 kHz/100 km VLF 3 kHz/100 km 30 kHz/10 km LF 30 kHz/10 km 300 kHz/1 km MF 300 kHz/1 km 3 MHz/100 m HF 3 MHz/100 m 30 MHz/10 m VHF 30 MHz/10 m 300 MHz/1 m UHF 300 MHz/1 m 3 GHz/100 mm SHF 3 GHz/100 mm 30 GHz/10 mm EHF 30 GHz/10 mm 300 GHz/1 mm THF 300 GHz/1 mm 3 THz/0.1 mm AM expanded band The extended mediumwave broadcast band , commonly known as

1406-788: The Communications Act of 1934 in late 1991 which mandated that priority for expanded band assignments would be given to existing daytime-only stations that were located in a community with a population over 100,000, and which also did not have any full-time stations. The two authorized stations that met this standard became the first two to begin broadcasting on the new band: WJDM, 1660 kHz in Elizabeth, New Jersey (now WWRU in Jersey City, New Jersey) in late 1995, and KXBT (now KDIA ), 1640 kHz in Vallejo, California in early 1996. These two are

1480-446: The FM broadcast band but require more energy and longer antennas. Digital modes are possible but have not reached momentum yet. MW was the main radio band for broadcasting from the beginnings in the 1920s into the 1950s until FM with a better sound quality took over. In Europe, digital radio is gaining popularity and offers AM stations the chance to switch over if no frequency in the FM band

1554-607: The Federal Communications Commission (FCC) to shut down, reduce power, or employ a directional antenna array at night in order to avoid interference with each other due to night-time only long-distance skywave propagation (sometimes loosely called ‘skip’). Those stations which shut down completely at night are often known as "daytimers". Similar regulations are in force for Canadian stations, administered by Industry Canada ; however, daytimers no longer exist in Canada,

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1628-490: The ionosphere and return to Earth at much greater distances; this is called the skywave . At night, especially in winter months and at times of low solar activity, the lower ionospheric D layer virtually disappears. When this happens, MW radio waves can easily be received many hundreds or even thousands of miles away as the signal will be reflected by the higher F layer . This can allow very long-distance broadcasting, but can also interfere with distant local stations. Due to

1702-591: The last station having signed off in 2013, after migrating to the FM band . Many countries have switched off most of their MW transmitters in the 2010s due to cost-cutting and low usage of MW by the listeners. Among those are Germany, France, Russia, Poland, Sweden, the Benelux, Austria, Switzerland, Slovenia and most of the Balkans. Other countries that have no or few MW transmitters include Iceland, Ireland, Finland and Norway. Large networks of transmitters are remaining in

1776-446: The 18 AM Classic Gold radio stations owned by Classic Gold Digital for a cash consideration of £3.95 million. GCap merged the network with its own Capital Gold network of stations to form one classic hits network. The acquisition, which included relevant DAB digital licences held by Classic Gold, was approved by Ofcom . The new network rebranded as 'Gold' launched at 7pm on Friday 3 August 2007. Weekdays Weekends included These were

1850-430: The 1930s adjacent higher frequencies had commonly been designated as a police radio band. Even after police radio transmissions were no longer made on this band, some county and city ordinances still forbade receivers capable of picking up transmissions on these frequencies, and they had reportedly been occasionally enforced to cite motorists in possession of amateur radio gear, or in extreme cases an AM radio installed in

1924-703: The 20 stations in the Classic Gold Digital Network on 3 August 2007: In addition, until 1 December 2008, the UTV Radio -owned Pulse Classic Gold in West Yorkshire broadcast programming supplied by the network, with additional localisation and programmes specific to West Yorkshire. This station relaunched as Pulse 2, a completely local station before closing in August 2020 to become Greatest Hits Radio West Yorkshire. Medium wave Medium wave ( MW )

1998-560: The FCC announced plans for an auction of new station assignments, which included replacing four AM stations recently deleted in the St. Louis , Missouri area. A suggestion to also include "abandoned AM expanded band facilities that were approved but never built" was denied. A 2022 FCC filing by Inspiration Media, Inc. characterized "the three decade-old expanded band plan" as so far providing only "exceedingly modest band-improvement". Within Australia ,

2072-642: The FCC expressed its intention to eventually eliminate the practice, stating: "We therefore tentatively conclude that any licensee with dual standard/Expanded Band authorizations... should be required to surrender one of the two authorizations within one year of release of a future Report and Order in this proceeding adopting this proposal..." This report also noted that "A total of 88 Expanded Band channels were originally allotted. There were 67 applications filed for Expanded Band allotments, of which 66 construction permits were granted, with one application still pending. Licenses were granted to 54 stations that migrated from

2146-530: The MW band consists of 120 channels with carrier frequencies from 531 to 1602 kHz spaced every 9 kHz. Frequency coordination avoids the use of adjacent channels in one area. The total allocated spectrum including the modulated audio ranges from 526.5 to 1606.5 kHz. Australia uses an expanded band up to 1701 kHz. North and South America use 118 channels from 530 to 1700 kHz using 10 kHz spaced channels. The range above 1610 kHz

2220-536: The MW band is thinning out, many local stations from the remaining countries as well as from North Africa and the Middle East can now be received all over Europe, but often only weak with much interference. In Europe, each country is allocated a number of frequencies on which high power (up to 2 MW) can be used; the maximum power is also subject to international agreement by the International Telecommunication Union (ITU). In most cases there are two power limits:

2294-515: The Netherlands and Italy. These frequencies are also used by a number of "hobby" pirate radio stations, particularly in the Netherlands , Greece , and Serbia . Vatican Radio for many years transmitted on 1611 kHz, before ceasing broadcasts on this frequency in 2012. Since 2014 a licensed Norwegian project has been broadcasting both Radio Northern Star and The Sea on 1611 kHz. In 1979,

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2368-459: The U.S. the same privilege on the other frequencies. Therefore, all of its limited number of expanded band stations currently operate on these frequencies. There have only been a few expanded band stations established in Cuba. The most commonly used frequency is 1620 kHz, where multiple stations simulcast Radio Rebelde network programming. Mexico has a total of four radio stations licensed for

2442-492: The UK, Spain and Romania. In the Netherlands and Scandinavia, some new idealistically driven stations have launched low power services on the former high power frequencies. This also applies to the ex-offshore pioneer Radio Caroline that now has a licence to use 648 kHz, which was used by the BBC World Service over decades. In Italy, the government closed its high power transmitters but low power private stations remain. As

2516-803: The audio is reproduced. This is a major disadvantage compared to FM and digital modes where the demodulated audio is more objective. Extended audio bandwidths cause interference on adjacent channels. Wavelengths in this band are long enough that radio waves are not blocked by buildings and hills and can propagate beyond the horizon following the curvature of the Earth; this is called the groundwave . Practical groundwave reception of strong transmitters typically extends to 200–300 miles (320–480 km), with greater distances over terrain with higher ground conductivity , and greatest distances over salt water. The groundwave reaches further on lower medium wave frequencies. Medium waves can also reflect off charged particle layers in

2590-511: The control of GCap (formerly GWR & Capital). Most stations in the network carried the same programming, except for a local 4-hour afternoon programme from 3pm to 7pm. Additionally, the AM service operated by UTV Radio in West Yorkshire , Pulse Classic Gold , carried programming supplied by the Classic Gold network (with additional localisation and programmes), although it was not owned by UBC. In summer 2007, GCap Media agreed to acquire

2664-535: The country and/or abroad), no longer having to broadcast weather and government reports on a different frequency than entertainment. Class A and B stations were segregated into sub-bands. In the US and Canada the maximum transmitter power is restricted to 50 kilowatts, while in Europe there are medium wave stations with transmitter power up to 2 megawatts daytime. Most United States AM radio stations are required by

2738-604: The end of the Cold War and the increased availability of satellite and Internet TV and radio, although the cross-border reception of neighbouring countries' broadcasts by expatriates and other interested listeners still takes place. In the late 20th century, overcrowding on the Medium wave band was a serious problem in parts of Europe contributing to the early adoption of VHF FM broadcasting by many stations (particularly in Germany). Due to

2812-477: The existing AM band, by transferring selected stations to the new frequencies. It was now estimated that the expanded band could accommodate around 300 U.S. stations. The common FCC practice for station applications on the standard AM frequencies is to process the applications individually. For the expanded band, the Commission decided to allocate the entire band at once on a nationwide basis, after evaluating all of

2886-499: The expanded band prior to 2017: XEUT-AM 1630, XEARZ-AM 1650, XEANAH-AM 1670, and XEPE-AM 1700. Both XEARZ (5 kW) and XEPE (10 kW) operate with nighttime power greater than 1 kW. These stations were authorized before changes in 2014 set aside the AM expanded band, along with 106-108 MHz on FM, for social community and social indigenous radio stations. With the exception of XEFCR-AM in Reynosa, Tamaulipas , all of

2960-401: The fall of 1994, the FCC announced that, out of 688 applicants, a specially designed computer program (which took two weeks to run) had chosen 79 stations to make the transfer to the expanded band. However, a year later the Commission rescinded these assignments, after it was determined that there had been major flaws in the data used to evaluate the applications. A provision had been added to

3034-578: The frequency. Because such tall masts can be costly and uneconomic, other types of antennas are often used, which employ capacitive top-loading ( electrical lengthening ) to achieve equivalent signal strength with vertical masts shorter than a quarter wavelength. A "top hat" of radial wires is occasionally added to the top of mast radiators, to allow the mast to be made shorter. For local broadcast stations and amateur stations of under 5 kW, T- and L-antennas are often used, which consist of one or more horizontal wires suspended between two masts, attached to

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3108-423: The ground. Shunt-excited masts, in which the base of the mast is at a node of the standing wave at ground potential and so does not need to be insulated from the ground, have fallen into disuse, except in cases of exceptionally high power, 1 MW or more, where series excitation might be impractical. If grounded masts or towers are required, cage or long-wire aerials are used. Another possibility consists of feeding

3182-673: The high demand for frequencies in Europe, many countries set up single frequency networks; in Britain , BBC Radio Five Live broadcasts from various transmitters on either 693 or 909 kHz. These transmitters are carefully synchronized to minimize interference from more distant transmitters on the same frequency. In Asia and the Middle East, many high-powered transmitters remain in operation. China , Indonesia , South Korea , North Korea , Japan , Thailand , Vietnam , Philippines , Saudi Arabia , Egypt , India , Pakistan and Bangladesh still use medium wave. Israel returns to mediumwave after

3256-599: The higher frequencies, all of the TIS stations on 1610 kHz could be moved as a group to 1710 kHz, however this was never implemented. (Currently 1710 kHz is unused by TIS stations with one exception: a waiver has been granted to Hudson County, New Jersey to operate a single-frequency network (WQFG689)). When the ITU approved the extension of the "top end" of the AM band to 1700 kHz in 1988, few consumer radios could tune higher than about 1620 or 1630 kHz. However, it

3330-527: The larger cities, and a majority of stations assigned from 1611 to 1701 kHz are low-powered (400 watts or less) Narrowband Area Service stations (MF-NAS). The AM expanded band in Japan extends to 1629 kHz. 1620 kHz and 1629 kHz are normally used by Highway advisory radio and/or Roadside Stations along stretches of major expressways. Many Japanese AM radios, car stereos and other receivers (walkman, etc.) can tune up to 1629 kHz. 1611 kHz

3404-578: The limited number of available channels in the MW broadcast band, the same frequencies are re-allocated to different broadcasting stations several hundred miles apart. On nights of good skywave propagation, the skywave signals of a distant station may interfere with the signals of local stations on the same frequency. In North America, the North American Regional Broadcasting Agreement (NARBA) sets aside certain channels for nighttime use over extended service areas via skywave by

3478-486: The mast or the tower by cables running from the tuning unit to the guys or crossbars at a certain height. Directional aerials consist of multiple masts , which need not to be of the same height. It is also possible to realize directional aerials for mediumwave with cage aerials where some parts of the cage are fed with a certain phase difference. For medium-wave (AM) broadcasting, quarter-wave masts are between 153 feet (47 m) and 463 feet (141 m) high, depending on

3552-613: The most common antenna for broadcast reception is the ferrite-rod antenna , also known as a loopstick antenna. The high permeability ferrite core allows it to be compact enough to be enclosed inside the radio's case and still have adequate sensitivity. For weak signal reception or to discriminate between different signals sharing a common frequency directional antennas are used. For best signal-to-noise ratio these are best located outdoors away from sources of electrical interference. Examples of such medium wave antennas include broadband untuned loops, elongated terminated loops, wave antennas (e.g.

3626-403: The new assignment or elected to remain on the original frequency. The FCC originally assumed that the expanded band stations would simulcast the programming of the original standard band stations, and be licensed to the same community. However, in most cases the expanded band stations have run separate programming, and a few have moved to other communities. One policy the FCC has generally enforced

3700-453: The number of available expanded band frequencies, and because the sole U.S assignment for this frequency, KALT in Atlanta, Texas , was eventually deleted; currently there are no broadcasting stations licensed for 1610 kHz in the United States. The FCC gave approval for TIS stations to operate on 1620–1700, on a secondary basis, and it was informally suggested that, once most radios could tune to

3774-483: The only expanded band stations in the United States authorized to use 10 kW at night. Other U. S. stations generally use ten kilowatts during the day and one kilowatt at night, with non-directional antennas. An exception exists for stations that use antennas with higher than normal efficiency or those multiplexed with an existing station on a different frequency. KVNS in Brownsville, Texas, operates at 12% less than

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3848-416: The outbreak of Israel-Hamas war . China operates many single-frequency networks across the country. As of May 2023, many Japanese broadcasters like NHK broadcast in medium wave, with many high power transmitters operating across Japan. There are also some low power relay transmitters for rural areas. Some countries have stopped using mediumwave, including Malaysia and Singapore. Stereo transmission

3922-566: The pending proceeding Promoting Diversification of Ownership in the Broadcasting Services". In general the FCC has refused to consider assigning any stations to the expanded band which were not included in the March 17, 1997 approval list. In 2006 an exception was made to this policy for WRCR in Ramapo, New York, which was allowed to move from 1300 to 1700 kHz, with the FCC stating that a "waiver

3996-545: The radio will decode C-QUAM AM stereo, whereas a set labelled "FM Stereo/AM Stereo" or "AMAX Stereo" will support AM stereo. In September 2002, the United States Federal Communications Commission approved the proprietary iBiquity in-band on-channel (IBOC) HD Radio system of digital audio broadcasting , which is meant to improve the audio quality of signals. The Digital Radio Mondiale (DRM) system standardised by ETSI supports stereo and

4070-411: The reception of much longer distance signals (within a range of about 2,000 km or 1,200 miles). This can cause increased interference because on most channels multiple transmitters operate simultaneously worldwide. In addition, amplitude modulation (AM) is often more prone to interference by various electronic devices, especially power supplies and computers. Strong transmitters cover larger areas than on

4144-423: The relatively limited number of broadcasting stations compared to the more congested standard/legacy AM band. Despite the initial requirement that one of the two paired stations had to cease broadcasting by the end of a five-year period, as of 2015 there were 25 cases where co-owned standard band and expanded band stations were still active, some of which were approaching 20 years of operation. However, at this time

4218-417: The result is eleven additional frequencies, from 1611 kHz to 1701 kHz. The extended band is not officially allocated in Europe, and the trend of national broadcasters in the region has been to reduce the number of their AM band stations in favor of FM and digital transmissions. However, new Low-Power AM (LPAM) stations have recently come on the air from countries like Finland, Sweden, Norway, Denmark,

4292-566: The same part of the country broadcast simultaneously the resultant interference meant that usually neither could be heard clearly. The Commerce Department rarely intervened in such cases but left it up to stations to enter into voluntary timesharing agreements amongst themselves. The addition of a third "entertainment" wavelength, 400 meters, did little to solve this overcrowding. In 1923, the Commerce Department realized that as more and more stations were applying for commercial licenses, it

4366-520: The standard (8.8 kW day and 880 watts at night) due to treaty obligations with Mexico, and WIGT in Charlotte Amalie, U.S. Virgin Islands , is licensed for 920 watts both day and night, due to similar treaty restrictions with respect to France's territorial holdings of Martinique and Guadeloupe. On March 22, 1996 the FCC announced a revised allocation table, consisting of 87 stations, but this too

4440-508: The standard AM band to the Expanded Band. Of those, 22 unconditionally surrendered their standard band licenses and remained in the Expanded Band; three conditionally surrendered their standard band licenses, and four standard band licenses were canceled by the Commission. The Commission also received one unconditional surrender of an Expanded Band authorization and one conditional surrender, and it canceled one Expanded Band license." In 2021,

4514-520: The standard AM band transmitting frequencies of 531 to 1602 kHz are designated as the Broadcasting Services Band (BSB), while 1611 to 1701 kHz is designated as the "Mid-Frequency" band. A limited number of stations operate under commercial licences on 1611, 1620 and 1629 kHz. The 1992 Broadcasting Services Act introduced "narrowband" station classifications, for broadcasts targeting specialized non-general audiences, primarily in

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4588-411: The stations since assigned to the expanded band have been community or indigenous stations: XECSCA-AM , XECSCGU-AM , XECSIA-AM , XECSIB-AM and XECSIC-AM . In the United States, implementation of the North American Regional Broadcasting Agreement in 1941 by the Federal Communications Commission (FCC) had established 1600 kHz as the upper limit for the standard AM broadcast band. Beginning in

4662-429: The stations which notified the FCC that they were interested in moving to the new band. Faced with the difficult task of evaluating hundreds of applications, the FCC developed a multi-factored algorithm to rank the applicants. In addition to required separation standards, both within the United States and internationally, a major component of the evaluation was an individual station's "interference improvement factor", which

4736-482: The total height, where they are terminated in insulators and thence outwards to ground anchors . Thus the umbrella antenna uses the guy wires as the top-load part of the antenna. In all these antennas the smaller radiation resistance of the short radiator is increased by the capacitance added by the wires attached to the top of the antenna. In some rare cases dipole antennas are used, which are slung between two masts or towers. Such antennas are intended to radiate

4810-483: The upper end of the Region 2 AM broadcast band, by adding ten frequencies which spanned from 1610 kHz to 1700 kHz. The agreement provided for a standard transmitter power of 1 kilowatt, which could be increased to 10 kilowatts in cases where it did not result in undue interference. Even before the formal adoption of the expansion, a 50,000-watt religious station located on the island of Anguilla, British West Indies,

4884-429: The vehicle as original equipment. A small group of frequencies, starting at 1665 kHz, had been set aside for use by cordless telephones , however in 1983 a higher allocation was assigned, and production after October 1, 1984 of handsets transmitting on the lower frequencies was prohibited. Therefore, by 1988 the frequencies from 1610 to 1700 kHz were largely unoccupied, with one major exception: 1610 kHz

4958-418: Was an outstanding question about the number of stations, based on the proposed standards, that could be accommodated on the new frequencies, with the FCC noting that an engineering firm, Cohen, Dippell and Everist, had "submitted an analysis to demonstrate that instead of 25 to 30 stations per channel... their calculations show 'approximately 5 (certainly less than 10)' stations can be assigned per channel". In

5032-498: Was broadcasting on 1610 kHz as "The Caribbean Beacon". This station dated to the early 1980s, and is no longer on the air. In Argentina, the expanded band assignments are primarily in the region surrounding the nation's capital, Buenos Aires. Canada has made an informal agreement with the United States to allow Canadian stations operating on 1610, 1630, 1650, 1670 and 1690 kHz to be located closer to their common border than would normally be allowed, in exchange for allowing

5106-404: Was eventually withdrawn due to errors. A third, and final, allocation, now approving 88 stations, was announced on March 17, 1997. In order to ease the transition, the FCC provided that both the original station and its expanded band twin could optionally operate simultaneously for up to five years, after which owners would have to turn in one of the two licenses, depending on whether they preferred

5180-426: Was not practical to have every station broadcast on the same three wavelengths. On 15 May 1923, Commerce Secretary Herbert Hoover announced a new bandplan which set aside 81 frequencies, in 10 kHz steps, from 550 kHz to 1350 kHz (extended to 1500, then 1600 and ultimately 1700 kHz in later years). Each station would be assigned one frequency (albeit usually shared with stations in other parts of

5254-769: Was one of two primary frequencies (along with 530 kHz) that had been assigned for use by hundreds of low-powered Travelers Information Stations (TIS). Moreover, the controlling licensing authority for these stations was not the FCC, but instead was the National Telecommunications and Information Administration (NTIA), so coordination between the two agencies was required. It was concluded that, for operation on 1610 kHz, TIS and broadcasting stations were considered "co-primary" services, thus existing TIS stations were protected from having to move to new frequencies. The restriction imposed by having to protect existing TIS stations on 1610 kHz generally reduced by one

5328-424: Was reported at the time that FCC "officials have been meeting with American manufacturers of radio receivers to make an early start on producing sets capable of receiving signals in the new band..." and when the first U.S. expanded band radio station began operating in late 1995, it was estimated that by now there were 280 million radios capable of receiving the full expanded band. During the 1988 ITU conference, it

5402-402: Was suggested that as many as 500 U.S. stations could be assigned to the new frequencies. On April 12, 1990 the Federal Communications Commission (FCC) voted to begin the process of populating the expanded band. Although some individuals had hoped the commission would give preferences to minority-owner or daytime-only stations, it announced that the main priority would be reducing interference on

5476-407: Was the degree to which a move to the expanded band would decrease the amount of interference on its vacated frequency, especially at night. The FCC summarized its primary considerations as "fulltime operation with stereo, competitive technical quality, 10 kW daytime power, 1 kW nighttime power, non-directional antenna (or simple directional) and 400-800 km spacing between co-channel stations". There

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