Shortwave listening Shortwave listening , or SWLing , is the hobby of listening to shortwave radio broadcasts located on frequencies between 1700 kHz and 30 MHz . Listeners range from casual users seeking international news and entertainment programming , to hobbyists immersed in the technical aspects of radio reception and collecting official confirmations ( QSL cards ) that document their reception of distant broadcasts ( DXing ) . In some developing countries , shortwave listening enables remote communities to obtain regional programming traditionally provided by local medium wave AM broadcasters . One 2002 estimate placed the number of shortwave listeners worldwide in the hundreds of millions . The practice of long - distance radio listening began in the 1920s when shortwave broadcasters were first established in the US and Europe . Audiences discovered that international programming was available on the shortwave bands of many consumer radio receivers , and a number of magazines and listener clubs catering to the practice arose as a result . Shortwave listening was especially popular during times of international conflict such as World War II , the Korean War and the Persian Gulf War . Listeners use inexpensive portable " world band " radio receivers to access the shortwave bands , and some advanced hobbyists employ specialized communications receiver s featuring digital technology designed for optimum reception of shortwave signals , along with outdoor antennas to enhance performance . With the advent of the internet , many international broadcasters have scaled back or terminated their shortwave transmissions in favor of web - based program distribution , while others are moving from traditional analog to digital broadcasting modes in order to allow more efficient delivery of shortwave programming . The number of organized shortwave listening clubs has diminished along with printed magazines devoted to the hobby ; however , many enthusiasts continue to exchange information and news on the web . History . The practice of listening to distant stations in the medium wave AM broadcast band was carried over to the shortwave bands . Frank Conrad , an early pioneer of medium wave broadcasting with KDKA in Pittsburgh , instituted some of the first shortwave broadcasts around 1921 . Stations affiliated with General Electric and Crosley followed shortly after . United States shortwave broadcasters began transmitting popular radio programs in an attempt to attract foreign audiences . During the 1930s , new shortwave 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 such as Philips Radio ' s PCJJ began around 1927 . Germany , Italy , the Soviet Union , Britain , and many other countries soon followed , and some classic shortwave broadcasters got their start . The BBC began on shortwave as the " BBC Empire Service " in 1932 . 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 after its entry into World War II using the Yankee Doodle musical theme . While technically - minded shortwave listening hobbyists dwindled during the war years due in part to the demands of military service , casual listeners seeking war news from foreign broadcasters increased . Shortwave receiver manufacturers contributed to war production . Zenith launched the multi - band Trans - Oceanic series of radios in 1942 . In some other countries , during the war , listening to foreign stations was a criminal offense . Established in 1939 , 35 - kilowatt Chinese shortwave station XGOY broadcast programming aimed at listening - restricted Japan . The station was often bombed by the Japanese . Shortwave listeners notified families of prisoners of war when studio announcers at stations in Axis powers countries , such as Germany and Japan , read prisoner - written messages . Allied monitors notified families , but many shortwave listeners were often first to report the broadcasts . Listeners in other countries also monitored POW messages . New Zealand shortwave listeners reported POW voices broadcast over Radio Peking during the Korean War . In the 1950s and 60s , shortwave DX columns in US magazines such as " Popular Electronics " ′ " Tuning the Short Wave Bands " and " Electronics Illustrated " ′ s " The Listener " became news sources for serious radio listeners . " Popular Electronics " ′ " WPE Monitor Registration " program , begun in 1959 , even offered callsign - like identifiers 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 . When Popular Electronics and similar magazines expanded coverage of new electronics topics in the 1970s , this led to the cancellation of several long - time shortwave listening columns . Beginning with " Sweden Calling DXers " on Radio Sweden in 1948 ( there was a slightly earlier short - lived program from Radio Australia ) , many shortwave radio stations began programs providing news . Some of the other prominent DX programs were Radio Netherlands ' " DX Jukebox " ( which became " Media Network " ) , the " SWL Digest " on Radio Canada International , and the " Swiss Shortwave Merry - go - round " on Swiss Radio International . An example of notable shortwave programming was the " Happy Station Show " , popularly called the “ world ’ s longest - running shortwave radio program ” . The show originated on Philips Radio ' s PCJJ shortwave station in 1928 , continuing until 1940 . After World War II Radio Netherlands broadcast the show from 1946 until it terminated in 1995 . Producer and presenter Keith Perron “ resurrected ” Happy Station on March 12 , 2009 . Although no longer associated with Radio Netherlands , the new effort proclaims itself as “ transmitted globally via shortwave , podcasting and Internet streaming radio ” . During the Persian Gulf War in the 1990s , many Americans tuned into foreign news broadcasts on shortwave . Some electronics retailers even reported a " run " on portable shortwave receivers due to the increased interest at the time . Practices . Listening to shortwave broadcast stations for new 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 station s ) , or tuning in amateur radio stations . Listeners often obtain QSL card s ( which confirm contact ) 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 engineer s . 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 " ( now , regrettably defunct ) 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 . There are estimated to be millions of shortwave listeners . 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 . SWLs are varied , with no common age or occupation . David Letterman is an admitted fan of the British Broadcasting Corporation ( BBC ) . Some developing countries use shortwave as a means of receiving local and regional programming . China and Russia retransmits some domestic channels on shortwave that target listeners in far off provinces . Shortwave listening is also used as an educational tool in classrooms . Poor sound reproduction , unreliable signal quality , and inflexibility of access are seen as disadvantages . Some humanitarian organizations like " Ears to Our World " distribute portable , self - powered shortwave radios to less developed parts of the globe , enabling people in remote , impoverished parts of the world to get educational programming , local and international news , emergency information and music . Recently , the group was involved in sending radios to Haiti so victims of the 2010 Haiti earthquake could stay abreast of local disaster recovery efforts . Equipment . Shortwave radio receivers . Radios for shortwave reception generally have higher performance than those intended for the local AM or FM broadcast band , since dependable reception of shortwave signals requires a radio with increased sensitivity , selectivity , and stability . Modern shortwave radio receiver s are relatively inexpensive and easily accessible , and many hobbyists use portable " world band " receivers and built - in telescopic antennas . Serious hobbyists may use expensive communications receiver s and outdoor antenna located away from electrical noise sources , such as a dipole made from wire and insulators . Features typical of modern solid state communications receivers : Older 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 Elettra . 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 . A feature coming into wide use in modern shortwave receivers is DSP technology , short for digital signal processing . DSP is the use of digital means to process signals , and a primary benefit 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 . Another important trend in modern shortwave listening is the use of " PC radios " , or radios that are designed to be controlled by a standard personal computer . 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 . In pure software defined radio s , all filtering , modulation and signal manipulation is done in software , usually by a PC soundcard or by a dedicated piece of DSP hardware . Future of shortwave listening . The rise of the internet influenced many broadcasters to cease their shortwave transmissions in favor of broadcasting over the world wide web . When BBC World Service discontinued service to Europe , North America , Australasia , and the Caribbean , it generated many protests and activist groups such as the Coalition to Save the BBC World Service . In the US , the shifting of resources from shortwave to Internet and television by the Broadcasting Board of Governors , which oversees U . S . international broadcasting , has also resulted in reduced broadcasting hours in the English language . Although most of the prominent broadcasters continue to scale back their analog shortwave transmissions or completely terminate them , shortwave is still very common and active in developing regions such as parts of Africa . Some international broadcasters have turned to a digital mode of broadcasting called Digital Radio Mondiale for their shortwave 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 . Endorsed by the ITU , 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 . Shortwave listening also remains popular with some expatriates who tune in shortwave transmissions from their homeland . Additionally , a number of remotely controlled shortwave receivers located around the world are available to users on the web . While radio hobbyists report that the number of shortwave listening clubs has diminished and printed magazines devoted to the hobby are few , enthusiasts such as Glenn Hauser and others continue to populate web sites , and originate podcasts dedicated to the pursuit .