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Encyclopedia > Shortwave listening
Shortwave stations can be heard using an inexpensive portable "world band" receiver. More expensive ones come with special features, such as SSB reception and PLL accuracy.
Shortwave stations can be heard using an inexpensive portable "world band" receiver. More expensive ones come with special features, such as SSB reception and PLL accuracy.

Shortwave listening (abbreviated as SWLing) is the hobby of tuning for shortwave radio broadcasts located on shortwave frequencies, usually thought of as those from 1700 kHz (the upper limit of the AM broadcasting band) to 30 MHz (the lower limit of the tuning range of most scanner radios).[1] Image File history File links Download high resolution version (1200x900, 186 KB) Summary Licensing File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Shortwave listening ... Image File history File links Download high resolution version (1200x900, 186 KB) Summary Licensing File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Shortwave listening ... Shortwave radio operates between the frequencies of 3,000 kHz and 30 MHz (30,000 kHz) 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. ... 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. ... Many electronic systems use internal clocks which are required to be phase-aligned to and/or frequency multiples of some external reference clock. ... A hobby is a spare-time recreational pursuit. ... A solid-state, analog shortwave receiver Shortwave radio operates between the frequencies of 3 MHz (3,000 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... Sine waves of various frequencies; the lower waves have higher frequencies than those above. ... A kilohertz (kHz) is a unit of frequency equal to 1,000 hertz (1,000 cycles per second). ... AM broadcasting is radio broadcasting using Amplitude Modulation. ... A megahertz (MHz) is one million (106) hertz, a measure of frequency. ... ‹ The template below (Expand) is being considered for deletion. ...

Contents

Practices

Listening to shortwave broadcast stations for news and information programming is common, but for many shortwave listeners (abbreviated as "SWLs"), the goal is to receive as many stations from as many countries as possible, also known as DXing. "DXers" routinely test the limits of their antenna systems, radios and radio propagation knowledge. Specialized interests of shortwave listeners may include listening for shortwave utility, or "ute", transmissions such as shipping, sailing, naval, aviation, or military signals, listening for intelligence signals (numbers stations), or tuning in amateur radio stations.[1] For other uses, see News (disambiguation). ... A radio station is an audio (sound) broadcasting service, traditionally broadcast through the air as radio waves (a form of electromagnetic radiation) from a transmitter to an antenna and a thus to a receiving device. ... DXing is the hobby of tuning in and identifying distant radio signals, or making two way radio contact with distant stations in amateur radio, citizens band radio or other two way radio communications hobbies. ... A Yagi-Uda beam antenna Short Wave Curtain Antenna (Moosbrunn, Austria) A building rooftop supporting numerous dish and sectored mobile telecommunications antennas (Doncaster, Victoria, Australia) An antenna is a transducer designed to transmit or receive radio waves which are a class of electromagnetic waves. ... Radio propagation is a term used to explain how radio waves behave when they are transmitted, or are propagated from one point on the Earth to another. ... Shipping is the transport of cargo between seaports by ships, typically large steel vessels powered by diesel engines or steam turbine plants. ... For either of the songs named Sailing, see Sailing (song). ... Navy is also:- shorthand for Navy Blue the nickname of the United States Naval Academy A navy is the branch of the armed forces of a nation that operates primarily on water. ... Aviation encompasses all the activities relating to airborne devices created by human ingenuity, generally known as aircraft. ... Intelligence (abbreviated or ) is the process and the result of gathering information and analyzing it to answer questions or obtain advance warnings needed to plan for the future. ... Numbers stations are shortwave radio stations of uncertain origin. ... Amateur radio station with modern solid-state transceiver featuring LCD and DSP capabilities Amateur radio, often called ham radio, is both a hobby and a service that uses various types of radio communications equipment to communicate with other radio amateurs for public service, recreation and self-training. ...

A Radio Moscow QSL card from 1969.
A Radio Moscow QSL card from 1969.

Listeners often obtain QSL cards from ham operators, broadcasters or utility stations as trophies of the hobby. Traditionally, listeners would send letters to the station with reception reports and requests for schedules. Many stations now accept E-mails or provide reception report forms on their Web sites. Reception reports give valuable information about propagation and interference to a station's engineers.[1] Image File history File links Radio_Moscow_logo. ... Image File history File links Radio_Moscow_logo. ... A 1969 Radio Moscow QSL card Voice of Russia is the Russian governments international radio broadcasting service. ... An example amateur radio QSL card QSL, or QSL card, is the confirmation of a QSO (a radio contact) between two radio amateurs. ... Wikipedia does not yet have an article with this exact name. ... Look up engineer in Wiktionary, the free dictionary. ...


There are several publications dedicated to providing information to shortwave listeners, including the magazines Popular Communications and Monitoring Times in the United States, and the annual publications Passport to World Band Radio and the World Radio TV Handbook (WRTH). In addition, stations can provide broadcast schedules through the mail or E-mail. There are also shortwave radio programs dedicated to shortwave listening and DXing, such as the U.S. based World of Radio and DXing With Cumbre, but recently these programs have been curtailed or dropped by many international broadcasters. As of 2007, Radio Habana Cuba still hosts a program called DXers Unlimited. For other uses, see United States (disambiguation) and US (disambiguation). ... This article does not cite any references or sources. ... Radio Habana Cuba (RHC) is the official international broadcasting station of Cuba. ...


While no one knows the exact number of SWLs, most estimates place the number in the millions. In 2002, according to the National Association Of Shortwave Broadcasters, for estimated numbers of households with at least one shortwave set in working order, Asia led with a large majority, followed by Europe, Sub Saharan Africa, and the former Soviet Union, respectively. The total estimated number of households worldwide with at least one shortwave set in working order was said to be 600,000,000.[2] SWLs range from teenagers to retired persons to David Letterman, who has mentioned on several occasions how much he enjoys listening to shortwave, particularly broadcasts by the British Broadcasting Corporation (BBC).[1] David Michael Letterman (born April 12, 1947, in Indianapolis, Indiana, U.S.) is an Emmy Award-winning American television host and comedian. ... This article is an overview article about the Crown chartered British Broadcasting Corporation formed in 1927. ...


History

The precursor of shortwave listening was long distance listening in the medium wave band, where broadcasting first developed. Mediumwave radio transmissions (sometimes called Medium frequency or MF) are those between the frequencies of 300 kHz and 3000 kHz. ...


Frank Conrad of Westinghouse, who developed the first medium wave broadcast station, KDKA in Pittsburgh, also set up the first shortwave broadcasts, as early as 1921. In 1924, the General Electric and Crosley companies started shortwave transmissions. Dr. Frank Conrad (1874-1941) was a radio broadcasting pioneer who worked as the Assistant Chief Engineer for the Westinghouse Electric Company in Pittsburgh, Pennsylvania. ... This article is about the defunct Westinghouse Electric Corporation founded in 1886, renamed CBS Corporation in 1997, and purchased by Viacom in 1999. ... KDKA (1020 kHz. ... City nickname: The Steel City Location in the state of Pennsylvania Founded 1758 Mayor Tom Murphy (Dem) Area  - Total  - Water 151. ... GE redirects here. ... Crosley Broadcasting Corporation, founded by radio manufacturing pioneer Powel Crosley Jr. ...

XGOY "The Voice of China" broadcast in 1942
XGOY "The Voice of China" broadcast in 1942

In the 1930s, shortwave broadcasters from the United States consisted of several private stations. The idea was to use popular American radio programs to attract audiences overseas, and thus to bring advertising revenue. But foreign audiences were difficult to measure, and were not always relevant to U.S. advertisers. During this decade, new receivers appeared on the market as well as popular shortwave magazines and clubs. Shortwave stations often offered unique QSL cards for DXers.


In Europe, shortwave broadcasts from Britain and the Netherlands began in 1927, and U.S. shortwave listeners could hear the well-organized international broadcasting efforts from Germany, Italy, the Soviet Union, Britain, and many other countries. Various well-known shortwave broadcasters became established. The BBC began as the "BBC Empire Service" in 1932 as a shortwave service.[3] Its broadcasts were aimed principally at English speakers. Radio Moscow was broadcasting on shortwave in English, French, German, Italian and Arabic by 1939. The Voice of America (or VOA) began broadcasting in 1942 as a result of the United States entry into World War Two and was introduced with the Yankee Doodle theme that is still familiar to shortwave listeners. For other uses, see Europe (disambiguation). ... // March 1 - Both NBC and CBS go to Hopewell, New Jersey to provide live coverage of the Lindbergh kidnapping. ... A 1969 Radio Moscow QSL card Radio Moscow was the official international broadcasting station of the Union of Soviet Socialist Republics. ... The English language is a West Germanic language that originates in England. ... Arabic redirects here. ... Year 1939 (MCMXXXIX) was a common year starting on Sunday (link will display the full calendar) of the Gregorian calendar. ... Voice of America logo Voice of America (VOA), is the official external radio and television broadcasting service of the United States federal government. ... This article is becoming very long. ... Yankee Doodle is a well-known US song, often sung patriotically today. ...


Shortwave listening remained as an organized hobby during the second world war, although in a reduced form, with so many DXers in the military service or working late hours in defense industries. Most shortwave receiver manufacturers shifted to the war effort, but Zenith began its popular multiband Trans-Oceanic series in 1942. In some other countries, during the war, listening to foreign stations was a criminal offense.[4] In broad terms, the zenith is the direction pointing directly above a particular location (perpendicular, orthogonal). ... The Trans-Oceanic was the name given to a series of portable radios produced from 1942 to 1981 by Zenith Radio. ...


In the 1950s and 60s, shortwave DX columns in US magazines such as Popular Electronics "Tuning the Short Wave Bands" and Electronics Illustrated "The Listener" became news sources for serious radio listeners. Electronics Illustrated "WPE Monitor Registration" program begun in 1959 even offered "callsigns" to hobbyists. A number of specialty radio clubs such as the Newark News Radio Club also arose during these decades and provided hobbyists with an exchange of DX news and information. In the 1970s, Popular Electronics and similar magazines expanded coverage of other areas of electronics lead to the cancellation of several longtime shortwave listening columns. [5] The Altair 8800 computer kit (January 1975) Popular Electronics was a magazine started by Ziff-Davis Publishing in October 1954 for hobbyist and experimenters in electronics. ...


Equipment

Shortwave radio receivers

Serious hobbyists may use expensive communications receivers and outdoor antennas. Typically, a modern solid state communications receiver will be of the superheterodyne type in double, triple or, more rarely, quad conversion. It will feature multiple RF and IF amplification stages and may have at least one IF stage that is crystal controlled. It will usually have an additional BFO product detector for SSB and CW reception capabilities. The frequency coverage of receivers of this type is typically in the range of 500 kHz to 30 MHz. A communications receiver is a type of radio receiver characterised by its frequency coverage, frequency selection, and range of adjustments to the radio signal. ... A Yagi-Uda beam antenna Short Wave Curtain Antenna (Moosbrunn, Austria) A building rooftop supporting numerous dish and sectored mobile telecommunications antennas (Doncaster, Victoria, Australia) An antenna is a transducer designed to transmit or receive radio waves which are a class of electromagnetic waves. ... In electronics, solid state circuits are those that do not contain vacuum tubes. ... The Super Heterodyne receiver (or to give it its full name, The Supersonic Heterodyne Receiver) was invented by Edwin Armstrong in 1918. ... It has been suggested that this article or section be merged with Radio waves. ... An intermediate frequency (IF) is a frequency to which a carrier frequency is shifted as an intermediate step in transmission or reception. ... A beat frequency oscillator or BFO in radio telegraphy, is a dedicated oscillator used to create an audio frequency signal for carrier wave transmissions to make them audible, as they are not broadcast as such. ... A product detector is a type of demodulator used for AM and SSB signals. ... 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 telegraphic information, using standardized sequences of short and long elements to represent the letters, numerals, punctuation and special characters of a message. ...


The front panel controls are typically more comprehensive than those on a local broadcast receiver. Usual features include: signal strength meter; RF gain control; AVC/AGC adjustments; antenna tuner; bandwidth filters; BFO tuning; audio limiters or attenuators. Frequency display dials may either be analog (typically marked to fine increments for accuracy) or digital.[6] The word broadcast can refer to: Broadcasting, the transmission of audio and video signals. ... The S-meter (signal strength meter) is an indicator often provided on communications receivers, such as amateur radio receivers, shortwave receivers, and the like. ... Automatic gain control (AGC) is an electronic system found in many types of devices. ... A modern ATU for ham operators. ... Bandwidth is the difference between the upper and lower cutoff frequencies of, for example, a filter, a communication channel, or a signal spectrum, and is typically measured in hertz. ...

Three portable shortwave receivers
Three portable shortwave receivers

The older generation of vacuum tube-based communications receivers are affectionately known as boatanchors for their large size and weight. Such receivers include the Collins R-390 and R-390A, the RCA AR-88, the Racal RA-17L and the Marconi Electra. However, even modern solid-state receivers can be very large and heavy, such as the Plessey PR2250, the Redifon R551 or the Rohde & Schwarz EK070.[7] Structure of a vacuum tube diode Structure of a vacuum tube triode In electronics, a vacuum tube, electron tube, or (outside North America) thermionic valve or just valve, is a device used to amplify, switch or modify a signal by controlling the movement of electrons in an evacuated space. ... In computing, a boat anchor is a piece of useless computer hardware - so-called because theoretically their only productive use is to be thrown into the water as a boat mooring (a common use for large obsolete or non-functional pieces of machinery). ... It has been suggested that this article or section be merged with Rockwell Collins. ... This article is about the former RCA Corporation. ... Racal Electronics plc was a British defence electronics firm purchased by Thomson-CSF (now Thales Group) in 2000. ... The Marconi Company Ltd. ... The famous decision by the United States Supreme Court can be found at Plessy v. ... Rohde & Schwarz (IPA: in German; anglicized pronunciation ) is an independent group of companies specializing in electronics. ...


Modern medium quality shortwave radio receivers tend to be relatively inexpensive and easily accessible. Many hobbyists use even less-expensive portable receivers with good results. In general, any given shortwave radio will benefit from an external antenna — even a simple wire antenna — as long as the antenna is away from electrical noise sources. The standard shortwave receiving antenna is the dipole antenna which can be readily purchased or made by hand from a roll of wire and a couple of insulators. For the device which is a tuner (radio) and a amplifier and/or loudspeaker, see receiver (home stereo). ... A simple half-wave dipole antenna that a shortwave listener might build. ...


Radios for shortwave reception generally have higher performance than those intended for the local AM or FM broadcast band. Good reception of shortwave signals requires a radio with good sensitivity, selectivity, and stability. Amplitude modulation (AM) is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. ... The abbreviations FM, Fm, and fm may refer to: Electrical engineering Frequency modulation (FM) and its most common applications: FM broadcasting, used primarily to broadcast music and speech at VHF frequencies FM synthesis, a sound-generation technique popularized by early digital synthesizers Science Femtometre (fm), an SI measure of length... The broadcast band is actually several chunks of the radio spectrum. ...


DSP technology

DSP technology, short for digital signal processing, is coming into wide use in modern shortwave receivers. The primary benefit of DSP hardware in shortwave receivers is the ability to tailor the bandwidth of the receiver to current reception conditions and to the type of signal being listened to. A typical analog only receiver may have a limited number of fixed bandwidths, or only one, but a DSP receiver may have 40 or more individually selectable filters. Digital signal processing (DSP) is the study of signals in a digital representation and the processing methods of these signals. ...


Under good band conditions with no adjacent channel interference, a wide bandwidth (i.e. 8 kHz or better) can produce quite pleasing shortwave audio reception. Under noisy band conditions the operator might want to shift to USB (i.e. upper sideband) mode or LSB mode (i.e. lower sideband) and a narrower DSP filter for improved reception. For voice communication, a bandwidth of as little as 2400 Hz could be adequate for intelligible reception. All AM modulated signals have the property of having both sidebands carry audio information. So a standard AM signal actually is three channels in one! There are many other simple "tricks of the trade" in shortwave listening that can dramatically improve reception results. Another technique is diversity reception, which is having two or more antennas that can be switched in or out in a type of "A to B" comparison to see which one provides the best signal.[8] 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. ... Terrestrial microwave radio system with two antenna arrays configured for space-diversity In telecommunications, a diversity scheme refers to a method for improving the reliability of a message signal by utilizing two or more communication channels with different characteristics. ...


PC controlled shortwave radio receivers

An important trend in modern shortwave listening is the growing use of so-called "PC radios", or radios that are designed to be controlled by a standard PC. These radios as the name suggests are controlled by specialized PC software using a serial port connected to the radio. A "PC radio" may not have a front-panel at all, and may be designed exclusively for computer control, which reduces cost. A "PC radio" is distinct from a pure SDR or Software defined Radio, which is discussed in its own section below. The PC radio in question may or may not have a front-panel and may be DSP capable. Many older radio designs dating back to the late 1980s and early 1990s came equipped with a control serial port. Each manufacturer has created its own unique command set to control their particular radios. Software developers must then program a unique driver for each radio they want to control, a time consuming task. Windows XP loading drivers during a Safe Mode bootup A device driver, or a software driver is a specific type of computer software, typically developed to allow interaction with hardware devices. ...


Some PC radios have the great advantage of being field upgradable by the owner. New versions of the DSP firmware can be downloaded from the manufacturer's web site and uploaded into the flash memory of the radio. The manufacturer can then in effect add new features to the radio over time, such as adding new filters, DSP noise reduction, or simply to correct bugs. A microcontroller, like this PIC18F8720 is controlled by firmware stored inside on FLASH memory In computing, firmware is a computer program that is embedded in a hardware device, for example a microcontroller. ... A USB flash drive. ...


A full-featured radio control program allows for scanning and a host of other functions and, in particular, integration of shortwave databases in real-time, like a "TV-Guide" type capability. This is particularly helpful in locating all transmissions on all frequencies of a particular broadcaster, at any given time. The most widely used free shortwave database is provided by a German company at ILGRadio. As of late 2006 they suspended the public broadcast database project and it is uncertain if they are going to resume it. As of 2008, the ILG database format is being updated as an open-source project called lOCHAM


Some control software designers have even integrated Google Earth to the shortwave databases, so it is possible to "fly" to a given transmitter site location with a click of a mouse. In many cases you are able to see the transmitting antennas where the signal is originating from.


Shortwave radio control software

The field of software control of PC radios has grown rapidly in the last several years, with developers making a number of advances. Since the Graphical User Interface or GUI interface PC to the radio has unlimited flexibility, any number of new features can be added by the software designer. GUI redirects here. ...


Here is a partial list of features that can be found in advanced shortwave control software programs today:

  • a band table which has a row corresponding to each slice of the shortwave broadcast spectrum. A click on the row sets up the GUI for the minimum and maximum frequencies for that band. A modulation mode is sent to the radio which is appropriate for that band (usually AM mode), when the row is clicked by the user.
  • a series of GUI controls corresponding to traditional radio controls such as frequency display, volume, mode, tuning rate and bandwidth. Usually included are a number of GUI slider controls. Moving the slider will tune the radio to a specific frequency and adjust the GUI frequency accordingly.
  • a local time clock and a UTC clock. By agreement all international shortwave broadcast schedules are constructed using UTC for standardization purposes.
  • a signal strength meter which returns a value from the radio and displays it on the GUI. This is useful for seeing the relative signal strength of the received signal.
  • some type of shortwave database, with the most widely used being the ILG database. The more advanced programs incorporate an interface to the ILG shortwave database. One control program displays a table that updates every minute that shows what stations are "on the air" in UTC time. This table can be pre-filtered by the user for languages. Simply clicking on a row of the table with a mouse tunes the radio to that frequency. In shortwave listening a frequency is sometimes referred to as a "channel". The shortwave bands are "channelized" at 5 kHz spacing.
  • a frequency database lookup capability. When tuning across a shortwave band it is extremely helpful to be able to ID a station quickly, especially if a foreign language is being spoken. Some programs display a list of frequencies in a table as the user tunes in real-time.
  • a scanning capability. This feature allows the user to tell the radio to start scanning from the beginning of the band to the other. As each frequency is tuned by the radio, the control program returns a signal strength to the control program and plots it. Once a scan of the band has been completed, the user can instantly see the state of the band in terms of which signals are strong and which signals are weak on any given frequency. By clicking on the plot display with a the mouse, the radio can be instantly tuned to that frequency. Using modulo arithmetic the programmer can guarantee that a mouse click always falls within the boundaries of a shortwave channel which is 5 kHz wide.
  • integration of scanning with the ILG and HFCC databases simultaneously. Designers have taken the next step in integration and merged scanning with databases. By "mousing over" a scan, a GUI "tool-tip" is displayed that shows information from the database as to what station is currently using that frequency.
  • text-to-speech interface. This feature can be optionally linked to frequency and mode changes or even database entries, to provide audio feedback to the user when certain fuinctions of the GUI are accessed.
  • an integrated Conference Server, which allows real-time real-time coordination of listening frequencies over the Internet. This allows users connected over the Internet, for example, to "remote-follow" the tuning of other radios automatically. Typically included is a "chat" facility which allows users to text the group as new listening frequencies arise.

Perhaps the most widely used pure PC shortwave radio (manufactured continuously since 1998) is the American made RX-320D DSP receiver. The "D" nomenclature is due to a design modification of the receiver, made by Ten-Tec circa 2004 that "taps" the 12 Khz IF output. This allows for the decoding of pure digital "pass through" signals such as DRM or Digital Radio Mondiale, as discussed elsewhere in this article. Otherwise the RX-320 and RX-320D receivers are identical in terms of their control and features. ... Modular arithmetic is a modified system of arithmetic for integers, sometimes referred to as clock arithmetic, where numbers wrap around after they reach a certain value (the modulus). ... Speech synthesis is the artificial production of human speech. ...


Software-defined radios

The next level in radio / software integration are so-called pure "software defined radios". The distinction here is that all filtering, modulation and signal manipulation is done in software, usually by a PC soundcard or by a dedicated piece of DSP hardware. There may be a minimal RF front-end or traditional radio that supplies an IF to the SDR. SDR's can go far beyond the usual demodulation capability of typical, and even high-end DSP shortwave radios. They can for example, record large swaths of the radio spectrum to a hard drive for "playback" at a later date. The same SDR that one minute is demodulating a simple AM shortwave broadcast may also be able to decode an HDTV broadcast in the next. A software-defined radio (SDR) system is a radio communication system which can tune to any frequency band and receive any modulation across a large frequency spectrum by means of programmable hardware which is controlled by software. ... It has been suggested that this article or section be merged with Radio waves. ... An intermediate frequency (IF) is a frequency to which a carrier frequency is shifted as an intermediate step in transmission or reception. ... Demodulation is the act of removing the modulation from an analog signal. ...


A well known open-source project called GNU Radio is dedicated to evolving a high-performance SDR. All the source code for this SDR is freely downloadable and modifiable by anyone. GNU Radio is a free software toolkit for learning about, building, and deploying Software Defined Radios. ...


Future of shortwave listening

The Internet caused many broadcasters to stop their HF transmissions and begin broadcasting over the net. One of these broadcasters was the BBC World Service, which discontinued service to Europe, North America, Australasia, and the Caribbean. generating many protests and creating many activist groups such as the Coalition to Save the BBC World Service. Note: broadcasting is also the old term for hand sowing. ... The BBC World Service is one of the most widely recognised international broadcasters, transmitting in 33 languages to many parts of the world through multiple technologies. ... For other uses, see Europe (disambiguation). ... North American redirects here. ... Australasia Australasia is a term variably used to describe a region of Oceania: Australia, New Zealand, and neighbouring islands in the Pacific Ocean. ... West Indies redirects here. ...


Most of the prominent broadcasters are scaling back their analog shortwave transmissions or completely terminating them, but especially in Africa shortwave is still very common and active. Many expatriates all around the world listen to shortwave transmissions to keep in touch, even after the advent of Internet-based news and publications. A world map showing the continent of Africa Africa is the worlds second-largest and second most-populous continent, after Asia. ... An expatriate (in abbreviated form expat) is someone temporarily or permanently in a country and culture other than that of their upbringing and/or legal residence. ...


The ramp-up of digital shortwave broadcasting using Digital Radio Mondiale is giving some international broadcasters pause in their rush to completely dismantle their shortwave broadcast outlets. One reason is that digital shortwave broadcasts using DRM can cover the same geographic region with much less transmitter power — roughly one fifth the power — than traditional AM mode broadcasts, significantly reducing the electricity cost of operating a station. A traditional AM (analog) international shortwave station can have a power rating of 50 kilowatts to as much as one million watts per transmitter, with typical power levels in the 50-500 kilowatt range. [9] 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. ...


Digital Radio Mondiale (DRM)

A digital mode of shortwave broadcasting is now starting to come into use. It has been approved as an international standard for digital broadcasts on the HF (shortwave) bands. A DRM broadcast rivals FM mono quality and can also send graphic images and web pages via a separate information channel. A DRM signal is typically decoded by a PC soundcard running a dedicated decoding program such as the open-source DREAM, although receivers with built-in DRM capability are starting to appear in the market (2006). 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 ITU recommends using 7 dB less power than for an equivalent analog broadcast, which means roughly one-fifth the amount of power. A DRM transmission using one-fifth the power of a current analog transmission should have a signal that is at least as good as the analog coverage.[10] The International Telecommunication Union (ITU; French: Union internationale des télécommunications, Spanish: Unión Internacional de Telecomunicaciones) is an international organization established to standardize and regulate international radio and telecommunications. ...


Shortwave listening outside English-speaking countries

South Korea

Since Korea has been divided into two states, shortwave listening in South Korea has never had a chance to activate itself. Shortwave or shortwave receivers were the symbol of North Korean spies or pro-North Korean activists because there were some incidents that proved this prejudice [11], and there were some cases in which the South Korean government confiscated shortwave receivers.[12] Until the liberalisation, it used to be a criminal offence for people without a ham radio operator's licence to possess a shortwave radio or listen to shortwave broadcasts.[13] In 1993, the South Korean authorities began to liberalse possession or listening of shortwave (receivers).[14]


Japan

The 1973 oil crisis brought the root of 'ethusiastic' shortwave listening to Japan. Due to the oil crisis, many Japanese broadcasters had to cease midnight programmes, therefore, a lot of listeners there began to seek shortwave listening as an alternative activity. During the 1970s and the 1980s, a large number of Japanese people, especially teenage students, were excited about shortwave, and electronics companies like Sony were interested in introducing several shortwave receivers. Some shortwave listeners would gather QSL cards from various broadcasters all over the world. After the 1980s, ethusiasm for shortwave listening in Japan began to go down. These days, most Japanese listeners are composed of certain adults who are specially interested in shortwave listening. Some of them are nostalgic of that period. Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $66. ...


References

  1. ^ a b c d Introduction To Shortwave Listening. DXing.com. Universal Radio Research. Retrieved on 2007-11-21.
  2. ^ http://shortwave.org/news/news0210.htm NATIONAL ASSOCIATION OF SHORTWAVE BROADCASTERS, Inc. October 2002
  3. ^ Analysis: BBC's voice in Europe Jan Repa, BBC News Online: 25 October 2005
  4. ^ http://www181.pair.com/otsw/review-elliott.html On the Short Waves, 1923 to 1945 by Jerome Berg
  5. ^ http://www181.pair.com/otsw/WPE.html On The Shortwaves
  6. ^ http://www.passband.com/pdf_files/HowToChoose.pdf Passport To WorldBand Radio
  7. ^ Osterman, Fred (1998). Shortwave Receivers Past & Present: Communications Receivers 1942-1997. Universal Radio Research, Reynoldsburg (USA).
  8. ^ http://www.passband.com/pdf_files/HowToChoose.pdf Passport To WorldBand Radio
  9. ^ http://www.drm.org/ Digital Radio Mondiale
  10. ^ http://www.passband.com/pdf_files/HowToChoose.pdf Passport To WorldBand Radio
  11. ^ MBC뉴스 - iMnews.com
  12. ^ MBC뉴스 - iMnews.com
  13. ^ http://www.crmo.go.kr/uploaddata/kukje/2004/kukje_01.pdf
  14. ^ 조선닷컴! 1등 인터넷뉴스

Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 325th day of the year (326th in leap years) in the Gregorian calendar. ...

See also

The purpose of this article is to explain the process and means of international broadcasting in a non-technical manner. ... Drake R8B communications receiver. ... 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 AM/MW or FM radio stations, as are common in Africa, Europe, Asia, Oceania and Latin America. ...

Literature

  • World Radio TV Handbook WRTH, ISBN 3-87463-356-X.
  • Passport to World Band Radio, www.passband.com, ISBN 0-914941-61-5 (2007 ed.) ISBN 978-0-914941-66-8 (2008 ed.)

External links

The following external link is designed for use by cell phones and mobile devices that can display content using Wireless Markup Language and the Wireless Application Protocol: Aurora australis observed by Discovery, May 1991. ... Radio propagation is a term used to explain how radio waves behave when they are transmitted, or are propagated from one point on the Earth to another. ... Cellular redirects here. ... A Handheld device (also known as handheld computer or simply handheld) is a pocket-sized computing device, typically utilising a small visual display screen for user output and a miniaturised keyboard for user input. ... Evolution of mobile web standards Wireless Markup Language, based on XML, is a content format for devices that implement the Wireless Application Protocol (WAP) specification, such as mobile phones, and preceded the use of other markup languages now used with WAP, such as XHTML and even standard HTML (which are... WAP is an open international standard for applications that use wireless communication. ...

  • WAP/WML SWL Resources Search database of International Shortwave Broadcasting Stations by frequency, view Space weather and radio propagation data and images, and more.
Aurora australis observed by Discovery, May 1991. ...

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Introduction to Shortwave Listening (1032 words)
Shortwave listening (abbreviated SWLing) is tuning for stations located on shortwave frequencies, usually thought of as those from 1700 kHz (the upper limit of the AM broadcasting band) to 30 MHz (the lower limit of the tuning range of most scanner radio).
Listeners to Germany's Deutsche Welle on October 3, 1990 heard live coverage of the reunification ceremonies and received this souvenir QSL card for their reception reports.
Shortwave reception is heavily influenced by solar activity as indicated by the number of sunspots visible on the Sun.
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