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Introduction
Imagine that you are obligated to live in a totalitarian government. The authority takes the control of the government and private radio and television channels.
You have internet, but the internet is controlled easily and for this reason, authority shuts access to many sites.
In Saudi Arabia and in Cuba use of the shortwave radio receivers is rather limited, and in the North Korea shortwave radio receivers are totally under the strong prohibition.
In the South Korea, shortwave radio receivers were prohibited till 1993.
Because of impossibility to censure shortwave radiobroadcast, shortwave radio receivers are being under prohibition.
Short waves are the radio waves, length of which reaches from 10 to 100 meters, they are reflected from the ionosphere due to the fact that they are absorbed very little in it.
General about short waves
Owing to the shortwave reflections from the ionosphere depending on the ionosphere layer, short waves can extent from 2000 to 4000 kilometers.
Due to the coverage of wide geographical territories, short waves are used for the international radiobroadcast.
Short waves may cover wider geographical territory in nighttime than in daytime. It is possible in nighttime to receive more radio stations than in daytime. It is required to use a shortwave radio receiver to receive the shortwave broadcast.
It is required to use a radio receiver that have a wide shortwave band, because they have a possibility to find more radiobroadcast.
Usually, on the switchers of radio receivers SW abbreviator, which means Short Waves in English. Get a radio receiver with the frequencies from 3 up to 22 megahertz. They have a possibility to get more channels.
Under housing conditions and especially under city conditions radiobroadcast receiving by short waves becomes some difficult because of different equipments and techniques at home and in the street.
Owing to the high sensitivity of the shortwave band to the waves coming from the different apparatus, radio receivers also receive these waves, as a result, the quality of receiving highly decreases.
Remove the radio receiver from the useless waves source at that moment. Sometimes you will be in need of an external antenna if your radio receiver is weak. For an external antenna a simple wire is wanted.
Advantages Of The Short Waves
Shortwave does posses a number of advantages over newer technologies.
The difficulty in censoring programming by authorities in target countries unlike the internet, government authorities have technical difficulties to monitor which stations are being listened to. For example, during the coup against president Mikhail Gorbachev, when his access to communications was limited, Gorbachev was able to stay informed by means of the BBC World Service on shortwave.
Low-cost shortwave radios are widely available in all but the most repressive countries in the world, such as North Korea.
Many newer shortwave receivers are portable and can be battery operated, making them useful in difficult circumstances. Newer technology includes hand-cranked radios which provide power for a short time. Shortwave radios can be used in situations where internet or satellite technology is unavailable or prohibited.
Shortwave radio travels much farther than broadcast FM. Shortwave broadcasts can be easily transmitted over a distance of several thousands of kilometers I.e. from one continent to another, especially at night.
Number Stations
Number stations are shortwave radio stations of uncertain origin. They generally broadcast artificially generated voices reading streams of numbers, words, letters, tunes or Morse code. Some stations duplicate their broadcast besides voices messages to Morse telegraph code on other frequencies. Evidence supports popular assumptions that the broadcasts are used to send messages to spies.
According to the notes of the Conet Project, number stations have been reported since First World War. Number stations operate as a simple and foolproof method for government agencies to communicate with spies working undercover. The messages are encrypted with a one time pad, to avoid any risk of decryption by the enemy.
High frequency radio signals transmitted at relatively low power can travel around the world under ideal propagation conditions, which are affected by local noise levels, weather, season, and sunspots, and can be received with a properly tuned antenna of adequate size, and a superb receiver. However, spies often have to work only with available hand held receivers, sometimes under difficult local conditions, and in all seasons and sunspot cycles.
Circa in 2000-2001 years, the United States has officially identified “Atencion” as Cuban spy station. “Attention” of Cuba became the world’s first number station to be officially and publicly accused of transmitting to spies. It was the center piece of a United States federal court espionage trial following the arrest of the “Wasp” network of Cuban spies in 1998. The United States prosecutors claimed the accused were writing down number codes received from “Atencion”, using Sony hand-held shortwave receivers, and typing the numbers into laptop computers to decode spying instructions.
The FBI testified that they had entered a spy’s apartment in 1995, and copied the computer decryption program for the “Atencion” numbers code. They used it to decode “Atencion” spy messages, which the prosecutes unveiled in court.
Number stations have changed details of their broadcast or produced special, nonscheduled broadcast coincident with extraordinary political events, such as the August Coup of 1991 in the Soviet Union.
Although no broadcaster or government has acknowledged transmitting the numbers, a 1998 article in “The Daily Telegraph” quoted a spokesperson for the Department of Trade and Industry, the government department that, at that time regulated radio broadcasting in the United Kingdom, as saying:
“These (number stations) are what you suppose they are. People shouldn’t be mystified by them. They are not for, shall we say, public consumption”.
Generally, number stations follow basic format, although there are many differences in details between stations. Transmission usually begin on the hour or half-hour. The prelude or introduction of a transmission includes some kind of identifier, either for the station itself and or for the intended recipient.
This can take the form of numeric or radioalphabet “code names” (“Charlie Indie Oscar”), characteristic phrases (“Atencion”) and sometimes musical or electronic sounds (“The Lincolnshire Poacher”). The prelude can also signify the nature or priority of the message to follow or indicate that no message follows. Often the prelude repeats for a period before the body of the message begins. There is usually an announcement of the number of number-groups in the message, then the groups are recited. Finally, after the messages have been sent, the station will sign off in some characteristic fashion. Usually it will simply be some form of the word “end” in whatever language the station uses. Some stations end with a series of zeros, others end with music or other sundry sounds.
Prohibitions On The Short Waves
Nazi Germany
Listening to foreign stations was a criminal offence in Nazi Germany. Penalties ranged from confiscation of radios and imprisonment to, particularly later in the war, the death penalty.
People’s receiver was a range of radio receivers developed by Otto Griessing at the request of Joseph Goebbels.
Volksempfangers were purposely designed only to receive local stations, so as to ensure that Nazi propaganda broadcasts could be heard while other media, such as the BBC’s World Service, could not. To this end most Volksempfangers lacked shortwave bands and didn’t follow the practice, common at the time among other receiver manufacturers, of marking the approximate dial positions of major European stations on its tuning scale.
The sensivity was lower than a normal radio although in practice it could with some difficulty still be used to receive foreign stations increased their transmissions power during the war.
North Korea
Radio receivers and television sets in North Korea are supplied pre-tuned to government stations and registered with the police.
This pre-tuning is strongly fixed and stations not tuned to government broadcasts are prohibited. Visitors and tourists are not allowed to bring a radio receiver.
If an ordinary inhabitant will be caught listening foreign broadcast, he will be threatened with harsh punishment up to imprisonment camps.
In the frames of information blockade politics, these modified radios and televisions should be registered at special state department. They are also subject to inspection at random. The removal of the official seal is punishable by law. In order to buy a TV set or a radio< Korean citizens should get special permission from the officials.
There also is a powerful shortwave transmitter for overseas broadcast in several languages.
Short Waves For A Political Propaganda
Radio Marti
Radio Marti is a radio broadcaster based in Florida, Miami, financed by the United States government, which transmits Spanish radio broadcasts to Cuba.
The radio was established in 1983 by president Ronald Reagan, at the urging of Jose Mas Canosa, with the mission of fighting against communism.
On may 20, 1985, broadcasts of the Radio Marti to Cuba from the United States began. The first day of broadcasting was chosen to commemorate the anniversary of Cuba’s independence from Spanish rule, May 20, 1902. The station came to be named Radio Marti after Cuban writer Jose Marti, who had fought for Cuba’s independence from Spain and against United States’ influence in the Americas. Today, Radio Marti is being transmitted short waves and medium waves.
Cuba jams both the medium wave and short wave signals, but the short wave program is heard in Canada and throughout Central and South America.
Former prisoners in Cuba and Cuban exiles often speak on Radio Marti; and on Saturdays a Spanish version of the United States’ president’s weekly radio address is transmitted.
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