20121214 1358UTC 15360kHz Trans World Radio Africa(Swaziland)
Date : 14/Dec/2012 1358UTC
Freq : 15360kHz AM
Rig : SDR(PI4THT)
ANT : GP
PC recording
Trans World Radio Africa HP
Radio Specifications
What to look for when buying a short wave radio?
The satisfactory reception of TWR places several demands on the radio used. While it is certainly possible to hear the programmes on most receivers, some special features are desirable to facilitate reception. A suitable radio should therefore possess certain qualities best summarized as follows :
- Sensitivity - the ability to receive weak signals.
- Selectivity - the ability to distinguish between signals separated by a small frequency difference.
- Stability - the ability to stay on a signal under variations of signal strength, changes in temperature, or vibration etc.
While most radios do indeed possess these qualities, this cannot be taken for granted. For this reason the following recommendations should provide some guidance.
- The frequency range of a radio which has short wave bands does not necessarily imply it covers the relevant bands. Make sure that the radio provides for reception on the short wave bands used by TWR. . (See our broadcast bands)
- Spreading the bands out is particularly useful on short wave. Many radios currently on the market try to cover all of the meter bands in the space of seven or eight centimeters on the radio dial. This reduces the effective width of any one meter band to half a centimeter or even less. Fifteen or more stations may be operating on this band, which means that tuning into a particular station on such a radio may be difficult. Try to locate a radio that spreads individual bands over a wide space on the dial. Some radios provide separate tuning for each of the short wave broadcast bands.
- Fine tuning is often included by many manufacturers on their radios to compensate for the crowded conditions of short wave. Rough tuning is done on the main tuning control and fine adjustments are then completed on this control.
- Many short wave receivers are not sensitive enough. Finding a radio that uses a large number of transistors and/or integrated circuits in its design will help ensure satisfactory reception. A radio having a powerful output and a large loudspeaker are not indicators of good reception.
All radios have a built-in automatic volume control. Its purpose is to give a reasonably consistent sound with varying strengths of the stations. A strong transmission along with any noise needs to be amplified less than a weak station. This is why a strong station sounds much clearer. Thus there are two ways to improve reception: decrease the amount of noise, or increase the strength of the signal with a good antenna.
Owning an expensive radio is not the answer to good listening. The largest factor in reception is determined by where your radio is located. High on top of a mountain is the best place, while the ground-floor flat dweller in a large city probably has the worst spot. A residential area generally provides a very satisfactory location. Wherever you stay, consider what affects reception and follow a few simple tips that will hopefully improve reception for you.
Short waves are transmitted over very long distances. Short wave signals bounce off the ionosphere and follow the curvature of the earth. The ionosphere, which is produced by the ultraviolet rays of the sun, consists of several layers of electrified particles encompassing the earth at a height of 100 to 300 km. The sun spot activity repeats in a cycle every eleven years and greatly affects short wave reception. Therefore, reception depends on the year, the season and the time of day.
TWR transmits several of its programmes on more than one meter band at the same time. Also, we change the meter bands throughout the day and in accordance with the time of year. The seasonal adjustments are normally carried out on the last Sunday of March and October and the broadcast schedules are updated accordingly.
Propagation
The radio signal from Swaziland will have covered a considerable distance before it reaches your radio. It may therefore suffer in quality. There are two main features of long range broadcasts worth mentioning.
- The ionosphere with its many layers is constantly shifting, subjecting the signal to occasional fading. This causes variations in signal strength. Hopefully this should not be serious and should still allow you to understand what is being said.
- The international broadcast bands are frequently very crowded and the many stations operating are in continual conflict for a clear spot. Occasionally another station may broadcast on a frequency very close to TWR. This is called interference. If you hear interference during our broadcasts, do not simply accept it. Often by fine-tuning your radio, you may be able to tune out the interference. Please report it to us. If we are aware of the problem it can possibly be rectified through our intervention. Within a few days you will notice that either the interfering station or TWR will have shifted frequency to a clear spot on the band.
Swaziland, officially the Kingdom of Swaziland (Swazi: Umbuso weSwatini), and sometimes called Ngwaneor Swatini, is a landlocked country in Southern Africa, bordered to the north, south and west by South Africa, and to the east by Mozambique. The nation, as well as its people, are named after the 19th century kingMswati II.
Swaziland is a small country, no more than 200 kilometres (120 mi) north to south and 130 kilometres (81 mi) east to west. The western half is mountainous, descending to a lowveld region to the east. The eastern border with Mozambique and South Africa is dominated by the escarpment of the Lebombo Mountains. The climate is temperate in the west, but may reach 40 °C (104 °F) in summer in the lowveld. Rainfall occurs mainly in the summer and may reach 2 metres (6.6 ft) in the west.
The area that Swaziland now covers has been continuously inhabited since prehistory. Today, the population is primarily ethnic Swazis whose language is Swati, though English is spoken as a second language. The Swazi people descend from the southern Bantu who migrated from Central Africa in the 15th and 16th centuries. The Anglo-Boer War saw the United Kingdom make Swaziland a protectorate under its direct control. Swaziland gained independence in 1968. Swaziland is a member of the Southern African Development Community, the African Union, and the Commonwealth of Nations. The head of state is the king, who appoints the prime minister and a small number of representatives for both chambers of parliament. Elections are held every five years to determine the majority of the representatives. A new constitution was adopted in 2005.
Some 75% of the population are employed in subsistence farming, and 60% of the population live on less than the equivalent of US$1.25 per day.[4] Swaziland's main trading partner is South Africa, and its currency is pegged to the South African rand. Many of Swaziland's peasants make their living by growing marijuana, which is sold to South Africa.[5] Swaziland's economic growth and societal integrity is highly endangered by its disastrous HIV epidemic, to an extent where the United Nations Development Program has written that if it continues unabated, the "longer term existence of Swaziland as a country will be seriously threatened."[6] The infection rate in the country is unprecedented and the highest in the world at 26.1% of adults,[7] and over 50% of adults in their 20s.[6] According to the CIA World Factbook, Swaziland has the lowest life expectancy in the world, with an average life expectancy of only 31.88 years.
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