A solid-state, analog shortwave receiver

Shortwave radio operates between the frequencies of 2,310 kHz and 30 MHz (30,000 kHz) ^[1] and came to be referred to as such in the early days of radio because the wavelengths associated with this frequency range were shorter than those commonly in use at that time. An alternate name is HF or high frequency radio. Short wavelengths are associated with high frequencies because there is an inverse relationship between frequency and wavelength. Image File history File linksMetadata Download high-resolution version (1024x768, 167 KB)[edit] Summary This is an example of a solid-state, multi-band shortwave receiver. ... Image File history File linksMetadata Download high-resolution version (1024x768, 167 KB)[edit] Summary This is an example of a solid-state, multi-band shortwave receiver. ... Sine waves of various frequencies; the bottom waves have higher frequencies than those above. ... The hertz (symbol: Hz) is the SI unit of frequency. ... MegaHertz (MHz) is the name given to one million (106) Hertz, a measure of frequency. ... The wavelength is the distance between repeating units of a wave pattern. ... High frequency (HF) radio frequencies are between 3 and 30 MHz. ... High frequency (HF) radio frequencies are between 3 and 30 MHz. ...

Overview

High-frequency propagation

Shortwave frequencies are capable of reaching the other side of the planet because they can be refracted by the ionosphere (a phenomenon known as Skywave propagation). The selection of a frequency to use to reach a target area depends on several factors: Relationship of the atmosphere and ionosphere The ionosphere is the part of the atmosphere that is ionized by solar radiation. ... It has been suggested that this article or section be merged with Ionosphere. ...

• The distance from the transmitter to the target receiver.
• Time of day. During the day, higher shortwave frequencies (> 12 MHz) can travel longer distances than lower ones; at night, this property is reversed.

The dependence to the time of the day is due to a particular transient atmosphere ionized layer forming only during day when atoms are broken up into ions by sun photons. This layer is responsible for partial or total absorption of particular frequences.

• Seasons, during the winter months the AM broadcast band tends to be more favorable because of longer hours of darkness.
• Solar conditions, including the number of sunspots, solar flares, and overall solar activity. Solar flares can prevent the ionosphere from reflecting or refracting radio waves.
• Type of modulation. Independent from the frequency, the receiver must be capable to receive the same modulation type of the transmitter. USB, LSB, AM, CW are all modes of modulation.

400 year sunspot history A sunspot is a region on the Suns surface (photosphere) that is marked by a lower temperature than its surroundings, and intense magnetic activity. ... A Solar Flare and CME, courtesy NASA A solar flare is a violent explosion in the Suns atmosphere with an energy equivalent to a billion megaton nuclear bombs, traveling at about 1 million km per hour. ...

Modulation formats used

Types of modulation frequently used in the shortwave frequency range are:

• AM: amplitude modulation. Usually used for shortwave broadcasting, and some aeronautical communications.
• NFM: Narrow-band frequency modulation. Because of the bandwidth required this is normally used for VHF communication, but some NFM transmissions occur in the higher HF frequencies.
• SSB: Single sideband(USB/LSB): This is used for long-range communications by ships and aircraft, for voice transmissions by amateur radio operators, and for broadcasting. LSB is generally used below 10mhz and USB above 10mhz.
• CW: Continuous/Carrier wave, which is used for Morse code communications.
• DRM: Digital Radio Mondiale: digital modulation for use on bands below 30 MHz.
• Various radioteletype, fax, digital, or other systems, which require software or special equipment to decode.

Frequency modulation (FM) is a form of modulation which represents information as variations in the instantaneous frequency of a carrier wave. ... This article or section does not cite its references or sources. ... Very high frequency (VHF) is the radio frequency range from 30 MHz to 300 MHz. ... Single-sideband modulation (SSB) is a refinement of the technique of amplitude modulation designed to be more efficient in its use of electrical power and bandwidth. ... 1922 Chart of the Morse Code Letters and Numerals Morse code is a method for transmitting information, using standardized sequences of short and long marks or pulses — commonly known as dots and dashes — for the letters, numerals, punctuation and special characters of a message. ... Digital Radio Mondiale (DRM) is a set of digital audio broadcasting technologies designed to work over the bands currently used for AM broadcast, particularly shortwave. ... This article does not cite its references or sources. ...

User base

Some major users of the shortwave radio band include

• Domestic broadcasting in countries with a widely dispersed population with few longwave, mediumwave, or FM stations serving them
• International broadcasting to foreign audiences (which explains why shortwave is also known as "world band radio")
• Speciality political, religious, and conspiracy theory radio networks, individual commercial and non-commercial paid broadcasts for the north American and other markets.
• Utility stations transmitting messages not intended for a general public, such as aircraft flying between continents, encoded or ciphered diplomatic messages, weather reporting, or ships at sea
• Numbers stations
• Amateur radio operators
• Time signal stations. WWV operates on these frequencies: 2500kHz, 5000kHz, 10000kHz, 15000kHz, and 20000kHz. CHU Canada operates on these frequencies: 3335kHz, 7335kHz, and 14670kHz.

The Asia-Pacific Telecommunity estimates that there are approximately 600,000,000 shortwave broadcast radio receivers in use in 2002. Broadcasting is the distribution of audio and/or video signals (programs) to a number of recipients (listeners or viewers) that belong to a large group. ... The Longwave radio broadcasting band is the range of frequencies between 148. ... Mediumwave radio transmissions serves as the most common band for broadcasting. ... International broadcasting is broadcasting deliberately aimed at a foreign, rather than a domestic, audience. ... A conspiracy theory attempts to explain the ultimate cause of an event (usually a political, social, or historical event) as a secret, and often deceptive, plot by a covert alliance of powerful people or organizations rather than as an overt activity or as natural occurrence. ... The term utility station is used to describe fixed radio broadcasters disseminating signals that are not intended for reception by the general public (but such members are not actively prohibited from receiving). ... Weather is a term that encompasses phenomena in the atmosphere of a planet. ... It has been suggested that Letter beacon be merged into this article or section. ... Amateur radio, often called ham radio, is a hobby and public service enjoyed by about 3 million people[1] throughout the world. ... A time signal is a visible, audible, mechanical, or electronic signal used as a reference to determine the time of day. ... For album titles with the same name, see 2002 (album). ...

ITU frequency allocation

The World Radiocommunication Conference (WRC), organized under the auspices of the International Telecommunication Union, allocates bands for various services in conferences every few years. The next WRC is scheduled to take place in 2007. World Radiocommunication Conference (WRC) is organized by ITU to review, and, if necessary, revise the Radio Regulations, the international treaty governing the use of the radio-frequency spectrum and the geostationary-satellite and non-geostationary-satellite orbits. ... Monument in Bern, Switzerland. ... 2007 (MMVII) will be a common year starting on Monday of the Gregorian calendar. ...

At the World Administrative Radio Conference (WARC) in 1997, the following bands were allocated to international broadcasters (listed in the table):

Amateur radio, often called ham radio, is a hobby and public service enjoyed by about 3 million people[1] throughout the world. ... Amateur radio, often called ham radio, is a hobby and public service enjoyed by about 3 million people[1] throughout the world. ...

Analog AM shortwave broadcasting channels are allocated with a 5 kHz separation.

International broadcasters, however, may operate outside the normal WARC-allocated bands or use off-channel frequencies to attract attention in crowded bands. The new digital audio broadcasting format for shortwave DRM operates in 5khz, 10khz or 20 khz channels -- so there are some ongoing discussions with respect to specific band allocation for DRM. Digital Radio Mondiale (DRM) is a set of digital audio broadcasting technologies designed to work over the bands currently used for AM broadcast, particularly shortwave. ...

The power used by shortwave transmitters ranges from less than one watt for some experimental transmissions to 500 kilowatts and higher for intercontinental broadcasters. Shortwave transmitting centers often use specialized antenna designs to concentrate radio energy on a bearing aimed at the target area. A yagi antenna Most simply, an antenna is an electronic component designed to send or receive radio waves. ...

Shortwave propagation

VOACAP coverage plot for a 25-meter-band, 500 kW transmitter located in British Columbia, Canada and feeding a directional antenna with a major lobe bearing of 252 degrees

Image File history File links Download high-resolution version (885x672, 25 KB) I have done some extensive computations on the feasability of an RCI SW relay station in British Columbia, this image is the result of some of my calculations. ... Image File history File links Download high-resolution version (885x672, 25 KB) I have done some extensive computations on the feasability of an RCI SW relay station in British Columbia, this image is the result of some of my calculations. ...

Shortwave propagation can currently be modeled by Ioncap (for point to point calculations) and VOACAP (for area coverage calculations). Ioncap is propagation prediction software, available for free from the U.S. Department of Commerce (NTIA/ITS) Institute for Telecommunication Sciences, originally developed for Voice of America (VOA). VOACAP is an improved version of IONCAP. VOACAP retains all of the theory as put forth by John Lloyd, George Haydon, Donald Lucas and Larry Teters in the 1975–1985 time-frame. Major improvements in the IONCAP program were made by Franklin Rhoads of the U.S. Navy Research Laboratory under the sponsorship of the Voice of America (1985–1996). The Institute for Telecommuncation Sciences (ITS) is a division of the National Telecommunications and Information Administration (NTIA) located in Boulder, Colorado. ... The Voice of America (VOA) is the official international broadcasting service of the Government of the United States. ...

Many of the newer features in VOACAP and VOAAREA were designed and implemented by Gregory Hand at the Institute for Telecommunication Sciences who created VOAAREA.

• VOACAP is the result of 50+ years HF research and development
• VOACAP is considered to be the most professional HF system performance prediction tool
• VOACAP is currently used for HF frequency planning by Voice of America and a number of other international HF broadcasters

Software

• http://www.its.bldrdoc.gov/elbert/hf.html

User guides

• http://www.voacap.com/

International broadcasting

See International broadcasting for details on the history and practice of broadcasting to foreign audiences. International broadcasting is broadcasting deliberately aimed at a foreign, rather than a domestic, audience. ...

Amateur radio

In the U.S. and Canada, no license is required to own or operate a shortwave receiver. The privilege of operating a shortwave radio transmitter, for non-commercial two way communications known as amateur radio, is granted through a licensing process by the authorized ITU government body. In the USA, this licensing agency is the Federal Communications Commission (FCC). In Canada, this licensing agency is Industry Canada. In February 1990, the FCC removed the morse code proficiency requirement for the Technician class amateur radio license, which allows one to transmit on frequencies above 30 MHz. Technician licensees who passed a 5 word per minute morse code test were allowed limited HF privileges, similar to those of Novice licensees. This has made it easier for beginners to get involved in the hobby; however, a working knowledge of Morse code is required to operate on shortwave bands. Amateur radio, often called ham radio, is a hobby and public service enjoyed by about 3 million people[1] throughout the world. ... The FCCs official seal. ... The Department of Industry, also referred to as Industry Canada, is the department of the government of Canada with responsibility for regional economic development, investment, and innovation/research and development. ... This article is about the year. ... 1922 Chart of the Morse Code Letters and Numerals Morse code is a method for transmitting information, using standardized sequences of short and long marks or pulses — commonly known as dots and dashes — for the letters, numerals, punctuation and special characters of a message. ... A megahertz (MHz) is one million (106) hertz, a measure of frequency. ... 1922 Chart of the Morse Code Letters and Numerals Morse code is a method for transmitting information, using standardized sequences of short and long marks or pulses — commonly known as dots and dashes — for the letters, numerals, punctuation and special characters of a message. ...

Amateur radio operators have made numerous technical advancements in the field of radio and make themselves available to transmit emergency communications when normal communications channels fail. Some amateurs practice operating off the power grid so as to be prepared for power loss. It should be noted that many amateur radio operators started out as Shortwave Listeners (SWLs) and actively encourage SWLs to become amateur radio operators.

The 2003 World Administrative Radio Conference (WARC) removed the global requirement for Morse code proficiency needed to access most shortwave frequencies for the amateur radio service, but left the decision to each administrative body (e.g. Federal Communications Commission in the United States; Industry Canada in Canada). 20 countries (largely Western Europe, Canada & Australia) have phased out this requirement from their licenses and giving access to operators who previously couldn't operate in HF. On the other hand, this trend is not global. Over 200 countries (e.g. Russia, Eastern Europe, Middle East, Africa, South America & Asia) have decided to keep the Morse Code requirement for the foreseeable future. In July 2005, the Federal Communications Commission recommended the removal of the Morse Code requirement for amateur radio licenses the United States, as part of a Notice of Proposed Rulemaking in WT Docket 05-235. This docket was released after 18 proposals, including one from the ARRL for widespread changes in the Amateur Radio Service rules were received and considered by the FCC. These proposals had attracted 6200 comments from the Amateur Radio Service community. It is not clear when the FCC will act on this.^[2] The word docket can mean: Look up docket in Wiktionary, the free dictionary. ... The American Radio Relay League (ARRL) was founded in May 1914 by Hiram Percy Maxim. ...

Shortwave listening

Many hobbyists listen to shortwave broadcasters without operating transmitters. In some cases, the goal is to hear as many stations from as many countries as possible (DXing); others listen to specialized shortwave utility, or "ute", transmissions such as maritime, naval, aviation, or military signals. Others focus on intelligence signals. Many though tune the shortwave bands for the programmes of stations broadcasting to a general audience (such as the Voice of America, BBC World Service, Radio Australia, etc.). Some even listen to two way communications by amateur radio operators. Nowadays, as the Internet evolves, the hobbyist can listen to shortwave signals via remotely controlled shortwave receivers around the world, even without owning a shortwave radio. (See for example http://www.dxtuners.com) Alternatively, many international broadcasters (such as the BBC) offer live streaming audio on their websites. Shortwaves can be heard using a cheap world band receiver. ... It has been suggested that DX station be merged into this article or section. ... The Voice of America (VOA) is the official international broadcasting service of the Government of the United States. ... The BBC World Service is one of the most widely recognised international broadcasters of radio programming, transmitting in 33 languages to many parts of the world. ... ABC Radio Australia is the international shortwave radio service operated by the Australian Broadcasting Corporation, Australias public broadcaster. ...

Shortwave listeners, or SWLs, can obtain QSL cards from broadcasters, utility stations or amateur radio operators as trophies of the hobby. Some stations even give out special certificates, pennants, stickers and other tokens and promotional materials to shortwave listeners. An example amateur radio QSL card QSL, or QSL card, is the confirmation of a QSO (a radio contact) between two radio amateurs. ...

Unusual signals

Numbers stations are shortwave radio stations of uncertain origin that broadcast streams of numbers, words, or phonetic sounds. Although officially there is no indication of their origin, radio hobbyists have determined that many of them are used by intelligence services as one-way communication to agents in other countries. From 1976 to 1989, the Russian Woodpecker blotted out countless shortwave broadcasts daily; at first it was thought to be a secret submarine communication system, but it was quickly found to be an early-warning over the horizon radar system. It has been suggested that Letter beacon be merged into this article or section. ... The Russian Woodpecker was a notorious Soviet signal that could be heard on the shortwave radio bands worldwide between July 1976 and December 1989. ... This long range RADAR antenna, known as ALTAIR, is used to detect and track space objects in conjunction with ABM testing at the Ronald Reagan Test Site on the Kwajalein atoll[1]. RADAR is a system that uses radio waves to determine and map the location, direction, and/or speed...

Shortwave's future

The development of direct broadcasts from satellites has reduced the demand for shortwave receivers, but there are still a great number of shortwave broadcasters. A new digital radio technology, Digital Radio Mondiale, is expected to improve the quality of shortwave audio from very poor to standards comparable to the FM broadcast band. The future of shortwave radio is threatened by the uprise of power line communication (PLC), also known as Broadband over Power Lines (BPL), where a data stream is transmitted over unshielded power lines. As the frequencies used overlap with shortwave bands, severe distortions make listening to shortwave radio near power lines difficult or impossible. This article needs to be cleaned up to conform to a higher standard of quality. ... Digital Radio Mondiale (DRM) is a set of digital audio broadcasting technologies designed to work over the bands currently used for AM broadcast, particularly shortwave. ... Power line communication (PLC), also called mains communication, power line telecoms (PLT), powerband or power line networking (PLN), is a term describing several different systems for using power distribution wires for simultaneous distribution of data. ... Power line communication (PLC), also called Broadband over Power Lines (BPL), is wireline method of communication using the existing electric power transmission and electricity distribution lines. ...

Shortwave broadcasts and music

Some musicians have been attracted to the unique aural qualities of shortwave radio, employing shortwave radios as live instruments in a number of pieces, and or using sampled broadcasts, used tape loops of broadcasts, or drawn inspiration from the unusual sounds on some frequencies. An AKAI MPC2000 sampler A sampler is an electronic musical instrument that can record and store audio signal samples, generally recordings of existing sounds, and play them back at a range of pitches. ... Tape loops are loops of prerecorded magnetic tape used to create repetitive, rhythmic musical patterns. ...

John Cage used radios live on several occasions, while Karlheinz Stockhausen used shortwave radio in works including Telemusik (1966), Hymnen (1966-67) and Spiral (1968). Holger Czukay, a Stockhauzen student, was one of the first to use shortwave in a rock music context. John Cage For the character of John Cage from the TV show Ally McBeal see: John Cage (Character) John Milton Cage (September 5, 1912 – August 12, 1992) was an American experimental music composer, writer and visual artist. ... Karlheinz Stockhausen (born August 22, 1928) is a German composer, one of the most important and controversial composers of the 20th century. ... Holger Czukay (born March 24, 1938) is a German musician. ... Rock is a form of popular music from the mid 20th century which typically features a vocal melody (often with vocal harmony) that is supported by accompaniment of electric guitars, a bass guitar, and drums, often with a strong back beat. ...

Among others, John Duncan, Orchestral Manoeuvres in the Dark (on their Dazzle Ships album), Pat Metheny, Aphex Twin, Boards of Canada, John Duncan, Rush, Able Tasmans, Meat Beat Manifesto, Daybrokenroses, Jonny Greenwood of Radiohead, and Wilco have also used or been inspired by shortwave broadcasts. For the Canadian politician, see John Duncan (Canadian politician). ... Orchestral Manoeuvres in the Dark (often abbreviated to OMD) are a synth pop group whose founder members are originally from the Wirral Peninsula, UK. OMD record for Virgin Records (originally for Virgins DinDisc subsidiary). ... Dazzle Ships is an album by Orchestral Manoeuvres in the Dark, released in 1983 (see 1983 in music). ... Patrick Bruce Metheny (born August 12, 1954 in Lees Summit, Missouri) is a world renowned American jazz guitarist and leader of the Pat Metheny Group as well as various collaborations, duets, solo works, and other side projects. ... Aphex Twin (Richard David James, born August 18, 1971 in Limerick, Ireland) is an electronic music artist, credited with pushing forward the genres of techno, ambient, acid, and drum and bass. ... Boards of Canada is a Scottish electronic music duo comprising Michael Sandison (b. ... For the Canadian politician, see John Duncan (Canadian politician). ... Rush is a Canadian progressive rock band comprising bassist, keyboardist, and vocalist Geddy Lee, guitarist Alex Lifeson, and drummer and lyricist Neil Peart. ... The Able Tasmans were an indie band from Auckland, New Zealand. ... Meat Beat Manifesto, often shortened to Meat Beat or MBM, is an electronic music outfit originally consisting of Jack Dangers and Jonny Stephens formed in 1987 in Swindon, UK. This was also the hometown of the band XTC, who helped Meat Beat get started. ... Jonathan Jonny Richard Guy Greenwood (born November 5, 1971 in Oxford, England) is a musician and a member of Radiohead. ... Radiohead are an English rock band from Oxfordshire. ... Wilco is an American rock band based in Chicago, Illinois. ...

See also

• List of American shortwave broadcasters
• International broadcasting
• Amateur radio
• Shortwave bands
• ALLISS (Antennas used in International Broadcasting)
• HRS type antennas (Antennas used in International Broadcasting)
• Superrock KYOI

Among the nations of the world, the USA is unique in that it has allowed private ownership of non-commercial shortwave stations that are not relays of existing MW or FM radio stations, as are common in Africa, Europe, Asia, Oceania and Latin America. ... International broadcasting is broadcasting deliberately aimed at a foreign, rather than a domestic, audience. ... Amateur radio, often called ham radio, is a hobby and public service enjoyed by about 3 million people[1] throughout the world. ... Shortwave bands are frequency allocations for use within the high frequency radio spectrum. ... This article may be too technical for most readers to understand. ... // What are HRS type antennas The curtain antenna is a dipole array, consisting of rows and columns of dipoles. ... Super Rock KYOI was a short-wave radio station located at Saipan island in Pacific region from 1982 to 1989 years. ...

External links and references

Citations

1. ^ Tomislav Stimac, "Definition of frequency bands (VLF, ELF... etc.)". IK1QFK Home Page (vlf.it).
2. ^ "FCC Proposes to Drop Morse Code Requirement for All License Classes", American Radio Relay League, Inc., July 20, 2005. Retrieved on 2006-08-03. (in English)

Other

• Shortwave Listening Guide
• DXing.info
• Monitoring Monthly - Radio Listeners' Magazine
• SWDXER ¨The SWDXER¨ - with general SWL information and radio antenna tips.
• Surfing the Aether A history of Shortwave Radio Broadcasting in the 1920s
• Buying Guide to Shortwave Radios
• The Conet project - Recordings of Shortwave Numbers Stations [ird059] (0)
• [1] minute by minute broadcast schedules and more
• [2] multilingual dx news
• [3] W1AW Code Practice Files
• [4] Weekly audio and archive updates "Glenn Hauser's World of Radio"

2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 3 is the 215th day of the year in the Gregorian Calendar (216th in leap years), with 150 days remaining. ... Radio frequency, or RF, refers to that portion of the electromagnetic spectrum in which electromagnetic waves can be generated by alternating current fed to an antenna. ... Extremely low frequency (ELF) is the band of radio frequencies from 3 to 30 Hz. ... Super Low Frequency (SLF) is the frequency range between 30 hertz and 300 hertz. ... Ultra Low Frequency (ULF) is the frequency range between 300 hertz and 3000 hertz. ... Very low frequency or VLF refers to radio frequencies (RF) in the range of 3 to 30 kHz. ... Low Frequency or LF refers to Radio Frequencies (RF) in the range of 30–300 kHz. ... Mediumwave radio transmissions (sometimes called Medium frequency or MF) are those between the frequencies of 300 kHz and 3000 kHz. ... High frequency (HF) radio frequencies are between 3 and 30 MHz. ... Very high frequency (VHF) is the radio frequency range from 30 MHz (wavelength 10 m) to 300 MHz (wavelength 1 m). ... This article is about the radio frequency. ... Microwave Slang for small waves, like at a beach, often used by surfers. ... Extremely high frequency is the highest radio frequency band. ...