Morse code is a telecommunications method which encodes text characters as standardized sequences of two different signal durations, called dots and dashes, or dits and dahs. Morse code is named after Samuel Morse, one of the early developers of the system adopted for electrical telegraphy.
Signals intelligence (SIGINT) is the act and field of intelligence-gathering by interception of signals, whether communications between people or from electronic signals not directly used in communication. As classified and sensitive information is usually encrypted, signals intelligence may necessarily involve cryptanalysis. Traffic analysis—the study of who is signaling to whom and in what quantity—is also used to integrate information, and it may complement cryptanalysis.
Shortwave radio is radio transmission using radio frequencies in the shortwave bands (SW). There is no official definition of the band range, but it always includes all of the high frequency band (HF), which extends from 3 to 30 MHz ; above the medium frequency band (MF), to the bottom of the VHF band.
International broadcasting consists of radio and television transmissions that purposefully cross international boundaries, often with then intent of allowing expatriates to remain in touch with their countries of origin as well as educate, inform, and influence residents of foreign countries. Content can range from overt propaganda and counterpropaganda to cultural content to news reports that reflect the point of view and concerns of the originating country or that seek to provide alternative information to that otherwise available as well as promote tourism and trade. In the first half of the twentieth century, international broadcasting was used by colonial empires as a means of connecting colonies with the metropole. When operated by governments or entities close to a government, international broadcasting can be a form of soft power. Less frequently, international broadcasting has been undertaken for commercial purposes by private broadcasters.
A numbers station is a shortwave radio station characterized by broadcasts of formatted numbers, which are believed to be addressed to intelligence officers operating in foreign countries. Most identified stations use speech synthesis to vocalize numbers, although digital modes such as phase-shift keying and frequency-shift keying, as well as Morse code transmissions, are not uncommon. Most stations have set time schedules, or schedule patterns; however, some appear to have no discernible pattern and broadcast at random times. Stations may have set frequencies in the high-frequency band.
CHU is the call sign of a shortwave time signal radio station operated by the Institute for National Measurement Standards of the National Research Council. CHU's signal is used for continuous dissemination of official Canadian government time signals, derived from atomic clocks.
Radio Havana Cuba is the official government-run international broadcasting station of Cuba. It can be heard in many parts of the world, including the United States, on shortwave frequencies. Radio Havana Cuba, along with Radio Rebelde, Cubavision Television, and other Cuban radio and television, broadcasts to North, Central and South America via free-to-air programming from the Hispasat 30W-6 satellite over the Atlantic Ocean and worldwide via Internet streaming.
Shortwave listening, or SWLing, is the hobby of listening to shortwave radio broadcasts located on frequencies between 1700 kHz and 30 MHz (30 000 kHz). Listeners range from casual users seeking international news and entertainment programming, to hobbyists immersed in the technical aspects of long-distance radio reception and sending and collecting official confirmations that document their reception of remote broadcasts (DXing). In some developing countries, shortwave listening enables remote communities to obtain regional programming traditionally provided by local medium wave AM broadcasters. In 2002, the number of households that were capable of shortwave listening was estimated to be in the hundreds of millions.
Radio jamming is the deliberate blocking of or interference with wireless communications. In some cases, jammers work by the transmission of radio signals that disrupt telecommunications by decreasing the signal-to-noise ratio.
The Lincolnshire Poacher was a powerful British shortwave numbers station that transmitted from HM Government Communications Centre near Gawcott in Buckinghamshire, England, and later from Cyprus, from the mid-1960s to July 2008. The station gained its commonly known name as it uses bars from the English folk song "The Lincolnshire Poacher" as an interval signal. The radio station was believed to be operated by the British Secret Intelligence Service. Amateur direction finding linked it with the Royal Air Force base at Akrotiri, Cyprus, where several curtain antennas were identified as being its transmitter. It consisted of a pre-recorded English-accented female voice reading groups of five numbers: e.g., '0-2-5-8-8'. The final number in each group was spoken at a higher pitch. It is likely that the station was used to communicate to undercover agents operating in other countries, to be decoded using a one-time pad.
UVB-76, also known by the nickname "The Buzzer", is a shortwave radio station that broadcasts in Upper Side Band mode on the frequency of 4625 kHz. It broadcasts a short, monotonous, repeating at a rate of approximately 25 tones per minute, 24 hours per day. Sometimes, the buzzer signal is interrupted and a voice transmission in Russian takes place.
A broadcast signal intrusion is the hijacking of broadcast signals of radio, television stations, cable television broadcast feeds or satellite signals without permission or licence. Hijacking incidents have involved local TV and radio stations as well as cable and national networks.
Ciocârlia is a Romanian tune, allegedly composed by the Romani-Romanian pan flute player Angheluş Dinicu in the virtuosic style of the urban lăutarească music from late 19th century.
"Wonderland by Night" is a popular song by Bert Kaempfert that was a Billboard number one hit for three weeks, starting January 9, 1961. Written by Klaus Günter Neumann with English lyrics by Lincoln Chase, it was recorded in July 1959 and became Bert Kaempfert's first hit with his orchestra. The song featured Charly Tabor on trumpet. "Wonderland by Night" also crossed over to the R&B chart where it peaked at number five.
Swedish Rhapsody No. 1 is the subtitle of Midsommarvaka, a symphonic rhapsody by the Swedish composer Hugo Alfvén (1872–1960). Although it is only the first of three similarly named works, it is often simply called "the Swedish Rhapsody".
The Pip is a shortwave radio station that broadcasts on the frequency 5448 kHz by day, and 3756 kHz during the night. It broadcasts short, repeated beeps at a rate of around 50 per minute, for 24 hours per day. The beep signal is occasionally interrupted by voice messages in Russian. The Pip has been active since 1986, when its distinctive beeping sound was first recorded by listeners, and is a sister station to UVB-76.
The Squeaky Wheel is a utility shortwave radio station that broadcasts a distinctive sound. From around 2000 until 2008 the station's attention tone was a high-pitched two tone signal that vaguely resembled a squeaky wheel. From 2008 the channel marker changed to two different tones in a short sequence repeated with a short silent gap. In 2023 the marker was changed to a low-tone pip marker.
The Tyrolean Music Station was a believed French shortwave numbers station that transmitted from Chartres in the Centre-Val de Loire region, France, from the early 1970s until late 1975. The station played several folk music songs by German yodeller Franzl Lang, prior to broadcasting one or several coded messages, and a music-box rendition of "The Internationale". The station was of unknown origin during the time it was broadcasting, until a French magazine, Interférences, claimed in their Autumn 1975 issue that the station was operated by the French intelligence service, SDECE. Shortly after this magazine was published, the station ceased broadcasting.
The Gongs or Chimes was a German shortwave numbers station that transmitted from Zeesen in the Brandenburg region of East Germany, between the early 1970s until 9 May 1990. The station would broadcast one or several coded messages daily during its operational life, with the messages being read out using an East German "Sprach-Morse Generator".
Star Star Broadcasting Station, the name also known as Xing Xing, or misidentified as New Star, is a short wave numbers station using upwards of 8000 kHz upper sideband modulation (USB), broadcasting from Taiwan, and is known for its introductory segments of Chinese flute playing.
