How To Use A Shortwave Radio

Radio transmissions using wavelengths betwixt 10 and 100 m

Shortwave radio is radio transmission using shortwave (SW) radio frequencies. At that place is no official definition of the band, but the range ever includes all of the loftier frequency band (HF), which extends from three to xxx MHz (100 to 10 metres); in a higher place the medium frequency band (MF), to the bottom of the VHF band.

Radio waves in the shortwave band tin can be reflected or refracted from a layer of electrically charged atoms in the atmosphere called the ionosphere. Therefore, short waves directed at an bending into the sky can be reflected back to Earth at great distances, beyond the horizon. This is called skywave or "skip" propagation. Thus shortwave radio tin be used for advice over very long distances, in contrast to radio waves of higher frequency, which travel in direct lines (line-of-sight propagation) and are limited by the visual horizon, almost 64 km (xl miles).

Shortwave broadcasts of radio programs played an important function in the early on days of radio history. In World War II it was used as a propaganda tool for an international audience. The heyday of international shortwave dissemination was during the Cold State of war between 1960 and 1980.

With the wide implementation of other technologies for the distribution of radio programs, such every bit satellite radio and cable broadcasting as well as IP-based transmissions, shortwave broadcasting lost importance. Initiatives for the digitization of broadcasting did non bear fruit either, and then as of 2022^[update], few broadcasters continue to circulate programs on shortwave.

All the same, shortwave remains important in war zones, such every bit in the Russo-Ukrainian war, and shortwave broadcasts tin be transmitted over thousands of miles from a single transmitter, making it difficult for regime authorities to censor them.

History [edit]

Development [edit]

Radio amateurs carried out the first shortwave transmissions over a long distance before those of Guglielmo Marconi.

The name "shortwave" originated during the beginning of radio in the early on 20th century, when the radio spectrum was divided into long wave (LW), medium wave (MW), and short wave (SW) bands based on the length of the moving ridge. Shortwave radio received its proper name because the wavelengths in this band are shorter than 200 m (one,500 kHz) which marked the original upper limit of the medium frequency band first used for radio communications. The broadcast medium wave band at present extends above the 200 grand / 1,500 kHz limit.

Early long-altitude radio telegraphy used long waves, beneath 300 kilohertz (kHz). The drawbacks to this system included a very express spectrum available for long-altitude communication, and the very expensive transmitters, receivers and gigantic antennas. Long waves are also difficult to beam directionally, resulting in a major loss of power over long distances. Prior to the 1920s, the shortwave frequencies to a higher place 1.v MHz were regarded as useless for long-altitude communication and were designated in many countries for amateur utilize.^[2]

Guglielmo Marconi, pioneer of radio, commissioned his assistant Charles Samuel Franklin to bear out a big-scale study into the manual characteristics of short-wavelength waves and to make up one's mind their suitability for long-distance transmissions. Franklin rigged up a large antenna at Poldhu Wireless Station, Cornwall, running on 25 kW of ability. In June and July 1923, wireless transmissions were completed during nights on 97 meters (about 3 MHz) from Poldhu to Marconi's yacht Elettra in the Republic of cape verde Islands.^[3]

In September 1924, Marconi arranged for transmissions to exist made 24-hour interval and nighttime on 32 meters (9.4& MHz) from Poldhu to his yacht in the harbour at Beirut, to which he had sailed, and was "astonished" to observe he could receive signals "throughout the day".^[4] Franklin went on to refine the directional transmission by inventing the curtain assortment aerial system.^[5] ^{[half dozen]} In July 1924, Marconi entered into contracts with the British General Mail service Office (GPO) to install high-speed shortwave telegraphy circuits from London to Australia, India, South Africa and Canada as the primary chemical element of the Imperial Wireless Chain. The United kingdom of great britain and northern ireland-to-Canada shortwave "Beam Wireless Service" went into commercial performance on 25 October 1926. Axle Wireless Services from the Uk to Australia, Southward Africa and India went into service in 1927.^[3]

Shortwave communications began to abound rapidly in the 1920s.^[7] Past 1928, more half of long-distance communications had moved from transoceanic cables and longwave wireless services to shortwave, and the overall book of transoceanic shortwave communications had vastly increased. Shortwave stations had cost and efficiency advantages over massive longwave wireless installations.^[8] However, some commercial longwave communications stations remained in apply until the 1960s. Long-distance radio circuits also reduced the need for new cables, although the cables maintained their advantages of high security and a much more reliable and better-quality signal than shortwave.

The cable companies began to lose large sums of money in 1927. A serious financial crisis threatened viability of cable companies that were vital to strategic British interests. The British authorities convened the Majestic Wireless and Cable Conference^[nine] in 1928 "to examine the situation that had arisen as a result of the competition of Beam Wireless with the Cable Services". It recommended and received authorities approval for all overseas cable and wireless resources of the Empire to be merged into one organisation controlled by a newly formed visitor in 1929, Imperial and International Communications Ltd. The proper noun of the visitor was changed to Cable and Wireless Ltd. in 1934.

A resurgence of long-altitude cables began in 1956 with the laying of TAT-1 across the Atlantic Bounding main, the first vox frequency cable on this road. This provided 36 high-quality telephone channels and was shortly followed by even higher-chapters cables all effectually the world. Contest from these cables presently concluded the economic viability of shortwave radio for commercial communication.

Apprentice use of shortwave propagation [edit]

Amateur radio operators also discovered that long-distance communication was possible on shortwave bands. Early long-altitude services used surface wave propagation at very low frequencies,^[10] which are attenuated forth the path at wavelengths shorter than one,000 meters. Longer distances and college frequencies using this method meant more bespeak loss. This, and the difficulties of generating and detecting college frequencies, fabricated discovery of shortwave propagation difficult for commercial services.

Radio amateurs may accept conducted the commencement successful transatlantic tests in December 1921,^[eleven] operating in the 200 meter mediumwave band (near 1,500 kHz, within the modern AM circulate band), which at that fourth dimension was the shortest wavelength / highest frequency available to amateur radio. In 1922 hundreds of N American amateurs were heard in Europe on 200 meters and at to the lowest degree 20 Northward American amateurs heard amateur signals from Europe. The first ii-style communications between Northward American and Hawaiian amateurs began in 1922 at 200 meters. Although operation on wavelengths shorter than 200 meters was technically illegal (but tolerated at the time every bit the authorities mistakenly believed that such frequencies were useless for commercial or war machine use), amateurs began to experiment with those wavelengths using newly bachelor vacuum tubes shortly after Earth War I.

Extreme interference at the longer edge of the 150–200 meter ring – the official wavelengths allocated to amateurs past the 2nd National Radio Conference^[12] in 1923 – forced amateurs to shift to shorter and shorter wavelengths; nevertheless, amateurs were express past regulation to wavelengths longer than 150 meters (ii MHz). A few fortunate amateurs who obtained special permission for experimental communications at wavelengths shorter than 150 meters completed hundreds of long-distance ii-way contacts on 100 meters (3 MHz) in 1923 including the commencement transatlantic two-way contacts.^[13]

By 1924 many additional specially licensed amateurs were routinely making transoceanic contacts at distances of 6,000 miles (9,600 km) and more. On 21 September 1924 several amateurs in California completed 2-way contacts with an apprentice in New Zealand. On nineteen October amateurs in New Zealand and England completed a ninety minute two-manner contact nearly halfway around the globe. On 10 Oct the 3rd National Radio Conference fabricated 3 shortwave bands available to U.Due south. amateurs^[fourteen] at 80 meters (3.75 MHz), 40 meters (vii MHz) and xx meters (14 MHz). These were allocated worldwide, while the x meter band (28 MHz) was created by the Washington International Radiotelegraph Conference^[15] on 25 Nov 1927. The xv meter band (21 MHz) was opened to amateurs in the United States on ane May 1952.

Propagation characteristics [edit]

Shortwave radio frequency free energy is capable of reaching whatever location on the Earth every bit it is influenced by ionospheric reflection back to the earth by the ionosphere, (a miracle known every bit "skywave propagation"). A typical phenomenon of shortwave propagation is the occurrence of a skip zone where reception fails. With a fixed working frequency, large changes in ionospheric conditions may create skip zones at night.

Equally a result of the multi-layer construction of the ionosphere, propagation frequently simultaneously occurs on different paths, scattered by the 'E' or 'F' layer and with different numbers of hops, a phenomenon that may be disturbed for certain techniques. Particularly for lower frequencies of the shortwave band, absorption of radio frequency energy in the everyman ionospheric layer, the 'D' layer, may impose a serious limit. This is due to collisions of electrons with neutral molecules, absorbing some of a radio frequency's energy and converting it to oestrus.^[16] Predictions of skywave propagation depend on:

The distance from the transmitter to the target receiver.
Time of day. During the solar day, frequencies higher than approximately 12 MHz can travel longer distances than lower ones. At night, this property is reversed.
With lower frequencies the dependence on the fourth dimension of the day is mainly due to the everyman ionospheric layer, the 'D' Layer, forming only during the day when photons from the lord's day intermission up atoms into ions and complimentary electrons.
Season. During the wintertime months of the Northern or Southern hemispheres, the AM/MW circulate ring tends to exist more favorable because of longer hours of darkness.
Solar flares produce a large increase in D region ionization – so peachy, sometimes for periods of several minutes, that skywave propagation is nonexistent.

Types of modulation [edit]

Several unlike types of modulation are used to incorporate information in a short-moving ridge signal.

Audio modes [edit]

AM [edit]

Amplitude modulation is the simplest blazon and the well-nigh commonly used for shortwave broadcasting. The instantaneous amplitude of the carrier is controlled by the amplitude of the indicate (voice communication, or music, for example). At the receiver, a simple detector recovers the desired modulation signal from the carrier.^[18]

SSB [edit]

Single-sideband transmission is a grade of amplitude modulation but in effect filters the upshot of modulation. An amplitude-modulated signal has frequency components both higher up and beneath the carrier frequency. If one ready of these components is eliminated as well as the residual carrier, but the remaining set is transmitted. This reduces power in the manual, as roughly 2⁄3 of the energy sent by an AM signal is in the carrier, which is not needed to recover the information independent in the signal. It also reduces bespeak bandwidth, enabling less than 1-half the AM bespeak bandwidth to be used.^[18]

The drawback is the receiver is more complicated, since it must re-create the carrier to recover the signal. Small errors in the detection procedure profoundly affect the pitch of the received signal. As a upshot, single sideband is non used for music or general circulate. Single sideband is used for long-range vocalisation communications past ships and aircraft, citizen'due south ring, and amateur radio operators. Lower sideband (LSB) is customarily used below 9 MHz and USB (upper sideband) above 9 MHz.

VSB [edit]

Vestigial sideband transmits the carrier and ane complete sideband, but filters out near of the other sideband. It is a compromise betwixt AM and SSB, enabling simple receivers to be used, but requires almost as much transmitter power as AM. Its main reward is that only one-half the bandwidth of an AM signal is used. It is used by the Canadian standard time signal station CHU. Vestigial sideband was used for analog boob tube and by ATSC, the digital Boob tube system used in Due north America.

NFM [edit]

Narrow-ring frequency modulation (NBFM or NFM) is used typically above 20 MHz. Because of the larger bandwidth required, NBFM is unremarkably used for VHF communication. Regulations limit the bandwidth of a betoken transmitted in the HF bands, and the advantages of frequency modulation are greatest if the FM signal has a wide bandwidth. NBFM is limited to short-range transmissions due to the multiphasic distortions created by the ionosphere.^[19]

DRM [edit]

Digital Radio Mondiale (DRM) is a digital modulation for use on bands beneath 30 MHz. Information technology is a digital betoken, like the data modes, below, but is for transmitting audio, similar the analog modes to a higher place.

Data modes [edit]

CW [edit]

Continuous wave (CW) is on-and-off keying of a sine-moving ridge carrier, used for Morse code communications and Hellschreiber facsimile-based teleprinter transmissions. Information technology is a data mode, although oftentimes listed separately.^[20] Information technology is typically received via lower or upper SSB modes.^[eighteen]

RTTY, FAX, SSTV [edit]

Radioteletype, fax, digital, slow-scan tv, and other systems employ forms of frequency-shift keying or audio subcarriers on a shortwave carrier. These generally require special equipment to decode, such as software on a figurer equipped with a sound card.

Annotation that on modern computer-driven systems, digital modes are typically sent by coupling a reckoner's sound output to the SSB input of a radio.

Users [edit]

Some established users of the shortwave radio bands may include:

International broadcasting primarily by government-sponsored propaganda, or international news (for example, the BBC World Service) or cultural stations to foreign audiences: The most mutual use of all.
Domestic broadcasting: to widely dispersed populations with few longwave, mediumwave and FM stations serving them; or for speciality political, religious and alternative media networks; or of individual commercial and non-commercial paid broadcasts.
Oceanic air traffic control uses the HF/shortwave band for long-distance communication to aircraft over the oceans and poles, which are far across the range of traditional VHF frequencies. Modern systems also include satellite communications, such as ADS-C/CPDLC.
Ii-style radio communications past marine and maritime HF stations, aeronautical users, and ground based stations.^[21] For example, two way shortwave advice is still used in remote regions past the Imperial Flying Dr. Service of Australia.^[22]
"Utility" stations transmitting letters non intended for the general public, such as merchant shipping, marine weather, and ship-to-shore stations; for aviation weather and air-to-ground communications; for armed services communications; for long-distance governmental purposes, and for other non-broadcast communications.
Apprentice radio operators at the 80/75, 60, xl, 30, 20, 17, xv, 12, and 10 meter bands. Licenses are granted by authorized government agencies.
Fourth dimension betoken and radio clock stations: In North America, WWV radio and WWVH radio transmit at these frequencies: 2.5 MHz, 5 MHz, 10 MHz, and xv MHz; and WWV also transmits on twenty MHz. The CHU radio station in Canada transmits on the following frequencies: iii.33 MHz, 7.85 MHz, and 14.67 MHz. Other like radio clock stations transmit on various shortwave and longwave frequencies around the world. The shortwave transmissions are primarily intended for human reception, while the longwave stations are generally used for automatic synchronization of watches and clocks.

Sporadic or non-traditional users of the shortwave bands may include:

Secret stations. These are stations that broadcast on behalf of diverse political movements such as rebel or insurrectionist forces. They may advocate civil war, coup, rebellion confronting the government-in-charge of the land to which they are directed. Clandestine broadcasts may emanate from transmitters located in rebel-controlled territory or from exterior the country entirely, using another land'southward manual facilities.^[23]
Numbers stations. These stations regularly appear and disappear all over the shortwave radio band, just are unlicensed and untraceable. Information technology is believed that numbers stations are operated by government agencies and are used to communicate with clandestine operatives working within strange countries. However, no definitive proof of such use has emerged. Because the vast bulk of these broadcasts incorporate nothing simply the recitation of blocks of numbers, in various languages, with occasional bursts of music, they take go known colloquially every bit "number stations". Perhaps the nearly noted number station is called the "Lincolnshire Poacher", named subsequently the 18th century English language folk song, which is transmitted just before the sequences of numbers.
Unlicensed two way radio activity by individuals such as taxi drivers, bus drivers and fishermen in various countries can be heard on diverse shortwave frequencies. Such unlicensed transmissions past "pirate" or "bootleg" two mode radio operators^[24] can often cause signal interference to licensed stations. Unlicensed business radio (taxis, trucking companies, amid numerous others) state mobile systems may be found in the xx-30 MHz region while unlicensed marine mobile and other like users may be found over the unabridged shortwave range.^[25]
Pirate radio broadcasters who feature programming such equally music, talk and other amusement, tin be heard sporadically and in various modes on the shortwave bands. Pirate broadcasters take reward of the better propagation characteristics to accomplish more than range compared to the AM or FM circulate bands.^[26]
Over-the-horizon radar: From 1976 to 1989, the Soviet Spousal relationship's Russian Woodpecker over-the-horizon radar organisation blotted out numerous shortwave broadcasts daily.
Ionospheric heaters used for scientific experimentation such as the High Frequency Active Auroral Research Programme in Alaska, and the Sura ionospheric heating facility in Russia.^[27]

Shortwave broadcasting [edit]

Encounter International broadcasting for details on the history and exercise of broadcasting to foreign audiences.
Encounter Listing of shortwave radio broadcasters for a listing of international and domestic shortwave radio broadcasters.
See Shortwave relay station for the bodily kinds of integrated technologies used to bring loftier power signals to listeners.

Frequency allocations [edit]

The World Radiocommunication Conference (WRC), organized under the auspices of the International Telecommunication Wedlock, allocates bands for diverse services in conferences every few years. The last WRC took identify in 2019.^[28]

At WRC-97 in 1997, the following bands were allocated for international broadcasting. AM shortwave dissemination channels are allocated with a 5 kHz separation for traditional analog sound broadcasting.

Metre Band	Frequency Range	Remarks
120 m	ii.3–2.495 MHz	tropical band
90 chiliad	3.2–iii.4 MHz	tropical ring
75 thousand	3.9–4 MHz	shared with the North American apprentice radio 80m band
60 m	4.75–v.06 MHz	tropical ring
49 one thousand	5.9–6.2 MHz
41 chiliad	7.ii–seven.6 MHz	shared with the amateur radio 40m band
31 yard	9.4–9.9 MHz	currently the nigh heavily used ring
25 k	eleven.6–12.2 MHz
22 m	thirteen.57–13.87 MHz
19 m	15.1–15.8 MHz
16 m	17.48–17.9 MHz
xv m	18.ix–xix.02 MHz	almost unused, could become a DRM band
xiii m	21.45–21.85 MHz
xi yard	25.half dozen–26.one MHz	may be used for local DRM broadcasting

Although countries by and large follow the table above, there may be small differences betwixt countries or regions. For example, in the official bandplan of kingdom of the netherlands,^[29] the 49 m band starts at v.95 MHz, the 41 thousand ring ends at 7.45 MHz, the 11 m band starts at 25.67 MHz, and the 120 m, 90 grand, and sixty m bands are absent altogether. Additionally, international broadcasters sometimes operate exterior the normal WRC-allocated bands or use off-channel frequencies. This is washed for applied reasons, or to attract attention in crowded bands (60 m, 49 m, xl m, 41 thou, 31 m, 25 m).

The new digital sound dissemination format for shortwave DRM operates 10 kHz or 20 kHz channels. There are some ongoing discussions with respect to specific band resource allotment for DRM, as it mainly transmitted in x kHz format.

The ability used by shortwave transmitters ranges from less than one watt for some experimental and apprentice radio transmissions to 500 kilowatts and higher for intercontinental broadcasters and over-the-horizon radar. Shortwave transmitting centers often apply specialized antenna designs (like the ALLISS antenna technology) to concentrate radio energy at the target area.

Advantages [edit]

Shortwave does possess a number of advantages over newer technologies, including the following:

Difficulty of censoring programming by authorities in restrictive countries. Different their relative ease in monitoring and censoring the Net, government authorities face technical difficulties monitoring which stations (sites) are beingness listened to (accessed). For example, during the attempted coup against Soviet President Mikhail Gorbachev, when his admission to communications was limited (e.g. his phones were cut off, etc.), Gorbachev was able to stay informed by ways of the BBC World Service on shortwave.^[30]
Depression-cost shortwave radios are widely available in all but the most repressive countries in the globe. Uncomplicated shortwave regenerative receivers can be hands built with a few parts.
In many countries (especially in most developing nations and in the Eastern bloc during the Cold War era) ownership of shortwave receivers has been and continues to be widespread^[31] (in many of these countries some domestic stations as well used shortwave).
Many newer shortwave receivers are portable and can be battery-operated, making them useful in difficult circumstances. Newer technology includes mitt-cranked radios which provide power without batteries.
Shortwave radios tin can be used in situations where Internet or satellite communications service is temporarily, long-term or permanently unavailable (or unaffordable).
Shortwave radio travels much further than broadcast FM (88–108 MHz). Shortwave broadcasts can be easily transmitted over a altitude of several thousand miles, including from 1 continent to another.
Specially in tropical regions, SW is somewhat less prone to interference from thunderstorms than medium wave radio, and is able to cover a large geographic area with relatively low power (and hence cost). Therefore, in many of these countries it is widely used for domestic dissemination.
Very petty infrastructure is required for long-distance 2-way communications using shortwave radio. All one needs is a pair of transceivers, each with an antenna, and a source of free energy (such as a battery, a portable generator, or the electrical filigree). This makes shortwave radio 1 of the almost robust means of communications, which tin be disrupted only by interference or bad ionospheric conditions. Modern digital transmission modes such as MFSK and Olivia are even more robust, assuasive successful reception of signals well below the noise flooring of a conventional receiver.

Disadvantages [edit]

Shortwave radio'due south benefits are sometimes regarded as existence outweighed past its drawbacks, including:

In most Western countries, shortwave radio ownership is unremarkably limited to true enthusiasts, since most new standard radios do not receive the shortwave ring. Therefore, Western audiences are limited.
In the developed earth, shortwave reception is very difficult in urban areas considering of excessive noise from switched-mode power adapters, fluorescent or LED calorie-free sources, internet modems and routers, computers and many other sources of radio interference.
Audio quality may be limited due to interference and the modes that are used.

Shortwave listening [edit]

A pennant sent to overseas listeners by Radio Budapest in the belatedly 1980s

The Asia-Pacific Telecommunity estimates that there are approximately 600 million shortwave broadcast-radio receivers in use in 2002.^[32] WWCR claims that there are 1.v billion shortwave receivers worldwide.^[33]

Many hobbyists heed to shortwave broadcasters. In some cases, the goal is to hear as many stations from as many countries as possible (DXing); others mind to specialized shortwave utility, or "ute", transmissions such equally maritime, naval, aviation, or armed services signals. Others focus on intelligence signals from numbers stations, stations which transmit foreign broadcast usually for intelligence operations, or the two manner communications by apprentice radio operators. Some curt wave listeners behave analogously to "lurkers" on the Cyberspace, in that they listen simply, and never attempt to send out their ain signals. Other listeners participate in clubs, or actively transport and receive QSL cards, or become involved with amateur radio and outset transmitting on their own.

Many listeners tune the shortwave bands for the programmes of stations broadcasting to a general audience (such as Radio Taiwan International, Communist china Radio International, Voice of America, Radio French republic Internationale, BBC Earth Service, Vocalism of Korea, Radio Complimentary Sarawak etc.). Today, through the evolution of the Cyberspace, the hobbyist tin can listen to shortwave signals via remotely controlled or web controlled shortwave receivers around the world, even without owning a shortwave radio.^[34] Many international broadcasters offer alive streaming audio on their websites and a number have airtight their shortwave service entirely, or severely curtailed information technology, in favour of internet transmission.^[35]

Shortwave listeners, or SWLs, can obtain QSL cards from broadcasters, utility stations or amateur radio operators as trophies of the hobby. Some stations even requite out special certificates, pennants, stickers and other tokens and promotional materials to shortwave listeners.

Shortwave broadcasts and music [edit]

Some musicians take been attracted to the unique aural characteristics of shortwave radio which – due to the nature of amplitude modulation, varying propagation conditions, and the presence of interference – more often than not has lower fidelity than local broadcasts (particularly via FM stations). Shortwave transmissions oft have bursts of distortion, and "hollow" sounding loss of clarity at certain aural frequencies, altering the harmonics of natural sound and creating at times a foreign "spacey" quality due to echoes and phase distortion. Evocations of shortwave reception distortions have been incorporated into rock and classical compositions, by means of delays or feedback loops, equalizers, or even playing shortwave radios as live instruments. Snippets of broadcasts take been mixed into electronic audio collages and live musical instruments, by means of analogue record loops or digital samples. Sometimes the sounds of instruments and existing musical recordings are altered by remixing or equalizing, with diverse distortions added, to replicate the garbled effects of shortwave radio reception.^[36] ^[37]

The first attempts past serious composers to incorporate radio effects into music may be those of the Russian physicist and musician Léon Theremin,^[38] who perfected a form of radio oscillator as a musical musical instrument in 1928 (regenerative circuits in radios of the fourth dimension were prone to breaking into oscillation, adding various tonal harmonics to music and speech); and in the same year, the evolution of a French musical instrument called the Ondes Martenot by its inventor Maurice Martenot, a French cellist and former wireless telegrapher. Karlheinz Stockhausen used shortwave radio and effects in works including Hymnen (1966–1967), Kurzwellen (1968) – adapted for the Beethoven Bicentennial in Opus 1970 with filtered and distorted snippets of Beethoven pieces – Screw (1968), Pole, Expo (both 1969–1970), and Michaelion (1997).^[36]

Cypriot composer Yannis Kyriakides incorporated shortwave numbers station transmissions in his 1999 ConSPIracy cantata.^[39]

Holger Czukay, a student of Stockhausen, was ane of the first to utilise shortwave in a stone music context.^[37] In 1975, German electronic music ring Kraftwerk recorded a full length concept album around simulated radiowave and shortwave sounds, entitled Radio-Activeness.^[xl] The The'southward Radio Cineola monthly broadcasts drew heavily on shortwave radio audio.^[41]

Shortwave's future [edit]

The development of direct broadcasts from satellites has reduced the need for shortwave receiver hardware, but there are still a great number of shortwave broadcasters. A new digital radio technology, Digital Radio Mondiale (DRM), is expected to improve the quality of shortwave sound from very poor to standards comparable to the FM broadcast band.^[42] ^[43] The future of shortwave radio is threatened by the rise of power line communication (PLC), also known every bit Broadband over Power Lines (BPL), which uses a data stream transmitted over unshielded ability lines. As the BPL frequencies used overlap with shortwave bands, astringent distortions can make listening to analog shortwave radio signals near power lines hard or impossible.^[44]

According to Andy Sennitt, one-time editor of the Earth Radio Telly Handbook,

shortwave is a legacy technology, which is expensive and environmentally unfriendly. A few countries are hanging on to it, merely most have faced upward to the fact that the glory days of shortwave have gone. Religious broadcasters will still use it considering they are not too concerned with listening figures.^[42]

However, Thomas Witherspoon, editor of shortwave news site SWLingPost.com wrote that

shortwave remains the virtually accessible international communications medium that still provides listeners with the protection of complete anonymity.^[45]

In 2018, Nigel Fry, head of Distribution for the BBC World Service Group,

I still see a place for shortwave in the 21st century, especially for reaching areas of the earth that are prone to natural disasters that destroy local dissemination and Internet infrastructure.^[42]

During the 2022 Russian invasion of Ukraine, the BBC World Service launched two new shortwave frequencies for listeners in Ukraine and Russian federation, broadcasting English-linguistic communication news updates in an effort to avoid censorship by the Russian land.^[46]

References [edit]

^ "Grundig Satellit 400 international / professional". ShortWaveRadio.ch. Archived from the original on 13 February 2018. Retrieved 16 February 2018.
^ Nebeker, Frederik (6 May 2009). Dawn of the Electronic Age: Electrical Technologies in the Shaping of the Modern Earth, 1914 to 1945. John Wiley & Sons. pp. 157 ff. ISBN978-0-470-40974-9. Archived from the original on 20 August 2020. Retrieved viii Nov 2016.
^ ^a ^b Bray, John (2002). Innovation and the Communications Revolution: From the Victorian pioneers to broadband Internet. IET. pp. 73–75. ISBN9780852962183. Archived from the original on 29 April 2016. Retrieved eleven October 2015.
^ Marconi, Degna (1996) [1962]. My Father, Marconi. Toronto / New York: Edizione Frassinelli. p. 207. ISBN1-55071-044-three.
^ Beauchamp, 1000.G. (2001). History of Telegraphy. IET. p. 234. ISBN0-85296-792-6. Archived from the original on 25 January 2022. Retrieved 23 November 2007.
^ Burns, R.W. (1986). British Idiot box: The determinative years. IET. p. 315. ISBN0-86341-079-0. Archived from the original on 25 January 2022. Retrieved 23 November 2007.
^ Beyond the Ionosphere: 50 years of satellite communication (full text). 1997. ISBN9780160490545 . Retrieved 31 August 2012 – via Annal.org. ^{[ total commendation needed ]}
^ Hugill, Peter J. (4 March 1999). Global Communications Since 1844: Geopolitics and technology. Johns Hopkins University Press. pp. 129 ff. ISBN978-0-8018-6074-iv. Archived from the original on nineteen August 2020. Retrieved 16 February 2018.
^ "Cable and wireless PLC history". Archived from the original on xx March 2015.
^ "Marconi wireless on Cape Cod". Stormfax.com. Archived from the original on 2008-x-24. Retrieved 2009-05-24 .
^ "1921 – Club station 1BCG and the transatlantic tests". Radio Club of America. Archived from the original on vii November 2009. Retrieved five September 2009.
^ "Radio Service Bulletin No. 72". Bureau of Navigation. Department of Commerce. ii Apr 1923. pp. 9–13. Archived from the original on 22 November 2018. Retrieved 5 September 2009.
^ Raide, Bob, W2ZM; Gable, Ed, K2MP (2 Nov 1998). "Celebrating the first trans-Atlantic QSO!". Newington, CT: American Radio Relay League. Archived from the original on 30 November 2009.
^ Frequency or wave band allocations. Recommendations for Regulation of Radio Adopted past the Third National Radio Briefing. 6–10 October 1924. p. 15. Archived from the original on 8 March 2021. Retrieved 14 Apr 2019.
^ Continelli, Bill, W2XOY (1996). "Commodity #8". twiar.org. The Wayback Automobile. Schenectady Museum Amateur Radio Gild. Archived from the original on ten June 2007. Retrieved 2 July 2007. Historical note discusses an International Radiotelegraph Conference on 4 October 1927, its intrigues and fallout.
^ Rawer, Karl (1993). Wave Propagation in the Ionosphere. Dordrecht: Kluwer. ISBN0-7923-0775-5.
^ "Panasonic / National". ShortwaveRadio.ch. Archived from the original on 12 February 2018. Retrieved 16 Feb 2018.
^ ^a ^b ^c Rohde, Ulrich L.; Whitaker, Jerry (six December 2000). Communications Receivers: DSP, software radios, and design (3rd ed.). New York, NY: McGraw Loma Professional. ISBN0-07-136121-9. ISBN 978-007-136121-seven
^ Sinclair, Ian Robertson (2000). Audio and Hi-Fi Handbook. Newnes. pp. 195–196. ISBN0-7506-4975-5.
^ "Feld Hell Club". Google Sites. Archived from the original on 10 January 2017. Retrieved ix Jan 2017.
^ Ilčev, Stojče Dimov (10 Dec 2019). Global Aeronautical Distress and Safe Systems (GADSS): Theory and Applications. Springer Nature. ISBN9783030306328. Archived from the original on 25 January 2022. Retrieved 9 September 2021.
^ Berg, Jerome Southward. (20 September 2013). The Early Shortwave Stations: A Broadcasting History Through 1945. McFarland. ISBN9780786474110. Archived from the original on 25 Jan 2022. Retrieved 9 September 2021.
^ Sterling, Christopher H. (March 2004). Encyclopedia of Radio. Routledge. pp. 538 ff. ISBN978-ane-135-45649-8. Archived from the original on xix August 2020. Retrieved 28 November 2017.
^ Pop Mechanics. Hearst Magazines. January 1940. pp. 62 ff. Archived from the original on 17 Dec 2019. Retrieved 28 November 2017.
^ "IARU Monitoring System". iaru.org. International Amateur Radio Matrimony (IARU). Archived from the original on 1 Dec 2017. Retrieved 28 November 2017.
^ Yoder, Andrew R. (2002). Pirate Radio Stations: Tuning in to underground broadcasts in the Air and Online. McGraw Hill Professional. ISBN978-0-07-137563-4. Archived from the original on 2020-08-19. Retrieved 2017-11-28 .
^ Bychkov, Vladimir; Golubkov, Gennady; Nikitin, Anatoly (17 July 2010). The Temper and Ionosphere: Dynamics, processes and monitoring. Springer Science & Business organization Media. pp. 104 ff. ISBN978-xc-481-3212-6. Archived from the original on 19 August 2020. Retrieved 28 Nov 2017.
^ "Globe Radiocommunication Conference 2019 (WRC-xix), Sharm el-Sheikh, Egypt, 28 October to 22 Nov 2019". Itu.int. Retrieved 2022-03-16 .
^ "Nationaal Frequentieplan". rijksoverheid.nl. Archived from the original on 6 March 2014. Retrieved half-dozen March 2014.
^ "dxld7078". w4uvh.internet. Archived from the original on 9 April 2010. Retrieved 2009-10-21 .
^ Habrat, Marek. "Odbiornik "Roksana"" [Radio constructor's recollections]. Archived from the original on 6 June 2009. Retrieved v August 2008.
^ "[no title cited]". aptsec.org. Archived from the original on 10 February 2005.
^ Anderson, Arlyn T. (2005). "Changes at the BBC Earth Service: Documenting the World Service's motion from shortwave to web radio in Due north America, Australia, and New Zealand". Periodical of Radio Studies. 12 (2): 286–304. doi:x.1207/s15506843jrs1202_8. S2CID 154174203. cited in "WWCR FAQ". Archived from the original on xiv November 2006. Retrieved 8 Feb 2007.
^ "Alive tunable receivers". The Radio Reference Wiki. Archived from the original on 2020-01-02. Retrieved 2020-01-02 .
^ "Whatever Happened to Shortwave Radio?". Radio World. 2010-03-08. Retrieved 2022-03-xviii .
^ ^a ^b Wörner, Karl Heinrich (1973). Stockhausen: Life and work. Academy of California Press. pp. 76 ff. ISBN978-0-520-02143-3. Archived from the original on 18 August 2020. Retrieved 15 February 2018.
^ ^a ^b Sheppard, David (1 May 2009). On Some Faraway Beach: The life and times of Brian Eno. Chicago Review Press. pp. 275 ff. ISBN978-1-55652-107-2. Archived from the original on 25 January 2022. Retrieved fifteen February 2018.
^ The Wire. C. Parker. 2000. Archived from the original on twenty Baronial 2020. Retrieved 15 Feb 2018.
^ Dolp, Laura (xiii July 2017). Arvo Pärt's White Light. Cambridge University Press. pp. 83 ff. ISBN978-ane-107-18289-ix. Archived from the original on 19 Baronial 2020. Retrieved 22 February 2018.
^ Barr, Tim (31 August 2013). Kraftwerk: From Dusseldorf to the future with love. Ebury Publishing. pp. 98 ff. ISBN978-ane-4481-7776-9. Archived from the original on 18 Baronial 2020. Retrieved xvi Feb 2018.
^ "Radio Cineola". thethe.com. Archived from the original on 18 Dec 2011.
^ ^a ^b ^c Careless, James. "The evolution of shortwave radio". Radio Globe. NewBay Media. Archived from the original on 16 February 2018. Retrieved 16 February 2018.
^ Amaral, Cristiano Torres (2021). Guia Moderno do Radioescuta. Amazon.
^ Hrasnica, Halid; Haidine, Abdelfatteh; Lehnert, Ralf (14 January 2005). Broadband Powerline Communications: Network blueprint. John Wiley & Sons. pp. 34 ff. ISBN978-0-470-85742-7. Archived from the original on 19 August 2020. Retrieved 16 Feb 2018.
^ Witherspoon, Thomas. "[no title cited]". SWLingPost.com. ^{[ full citation needed ]}
^ "Millions of Russians turn to BBC News". BBC. Archived from the original on four March 2022. Retrieved 4 March 2022.

External links [edit]

"A beginner's guide to shortwave radio listening". SWLing.com.
Hauser, Glenn. "Globe of Radio".
"Space Conditions and Radio Propagation Center". propagation.hfradio.org. View alive and historical information and images of space weather and radio propagation.
"Short-wave radio, snap and crackle goes popular. Life in the sometime wireless yet". The Economist. commodity describing pros and cons of short moving ridge radio since the Cold War.
"Short-moving ridge radio telephone is success in tests". Popular Mechanics. Hearst Magazines. July 1931. mid page 114. describes experiments carried out for the French and British governments.
"Que Escuchar en la Onda Corta en Español". queescucharenlaoc.blogspot.com (in Spanish).