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Kronstorf Transmitter
The Kronstorf Transmitter was a mediumwave (and, starting in 1967, shortwave) broadcasting facility near Kronstorf, Austria. Its construction started in 1950 by the American Forces occupying Austria, and went in service on 1952-03-01. The transmitter, used for broadcasting in Soviet-controlled Austria, consisted of one 274 m and two 137 m guyed masts. On 1954-03-15, the facility was given to the Austrian broadcasting company, Österreichischer Rundfunk (ORF). A 274 m (900 ft) and a 137 m (450 ft) mast were dismantled in 1956, and then rebuilt at the Bisamberg transmission facility. There were further plans in the 1970s to renovate the transmitter, but as most of Austria is mountainous areas, medium wave propagation was not an efficient transmission method. The Kronstorf Transmitter was shut down in March 1994, and on 1995-01-26 the transmission mast was demolished by explosives. See also * List of masts The tallest structure in the world is the Burj Kh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mediumwave
Medium wave (MW) is the part of the medium frequency (MF) radio band used mainly for AM broadcasting, AM radio broadcasting. The spectrum provides about 120 channels with more limited sound quality than FM stations on the FM broadcast band. During the daytime, reception is usually limited to more local stations, though this is dependent on the signal conditions and quality of radio receiver used. Improved signal propagation at night allows the reception of much longer distance signals (within a range of about 2,000 km or 1,200 miles). This can cause increased interference because on most channels multiple transmitters operate simultaneously worldwide. In addition, amplitude modulation (AM) is often more prone to interference by various electronic devices, especially power supplies and computers. Strong transmitters cover larger areas than on the FM broadcast band but require more energy and longer antennas. Digital modes are possible but have not reached momentum yet. MW was th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wave Propagation
Wave propagation is any of the ways in which waves travel. Single wave propagation can be calculated by 2nd order wave equation ( standing wavefield) or 1st order one-way wave equation. With respect to the direction of the oscillation relative to the propagation direction, we can distinguish between longitudinal wave and transverse waves. For electromagnetic waves, propagation may occur in a vacuum as well as in the material medium. Other wave types cannot propagate through a vacuum and need a transmission medium to exist. Reflection of plane waves in a half-space The propagation and reflection of plane waves—e.g. Pressure waves (P-wave) or Shear waves (SH or SV-waves) are phenomena that were first characterized within the field of classical seismology, and are now considered fundamental concepts in modern seismic tomography. The analytical solution to this problem exists and is well known. The frequency domain solution can be obtained by first finding the Helmholtz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Towers Completed In 1952
A tower is a tall structure, taller than it is wide, often by a significant factor. Towers are distinguished from masts by their lack of guy-wires and are therefore, along with tall buildings, self-supporting structures. Towers are specifically distinguished from buildings in that they are built not to be habitable but to serve other functions using the height of the tower. For example, the height of a clock tower improves the visibility of the clock, and the height of a tower in a fortified building such as a castle increases the visibility of the surroundings for defensive purposes. Towers may also be built for observation, leisure, or telecommunication purposes. A tower can stand alone or be supported by adjacent buildings, or it may be a feature on top of a larger structure or building. Etymology Old English ''torr'' is from Latin ''turris'' via Old French ''tor''. The Latin term together with Greek τύρσις was loaned from a pre-Indo-European Mediterranean languag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1952 Establishments In Austria
Year 195 ( CXCV) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Scrapula and Clemens (or, less frequently, year 948 ''Ab urbe condita''). The denomination 195 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * Emperor Septimius Severus has the Roman Senate deify the previous emperor Commodus, in an attempt to gain favor with the family of Marcus Aurelius. * King Vologases V and other eastern princes support the claims of Pescennius Niger. The Roman province of Mesopotamia rises in revolt with Parthian support. Severus marches to Mesopotamia to battle the Parthians. * The Roman province of Syria is divided and the role of Antioch is diminished. The Romans annexed the Syrian cities of Edessa and Nisibis. Severus re-establish his h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Towers In Austria
A tower is a tall structure, taller than it is wide, often by a significant factor. Towers are distinguished from masts by their lack of guy-wires and are therefore, along with tall buildings, self-supporting structures. Towers are specifically distinguished from buildings in that they are built not to be habitable but to serve other functions using the height of the tower. For example, the height of a clock tower improves the visibility of the clock, and the height of a tower in a fortified building such as a castle increases the visibility of the surroundings for defensive purposes. Towers may also be built for observation, leisure, or telecommunication purposes. A tower can stand alone or be supported by adjacent buildings, or it may be a feature on top of a larger structure or building. Etymology Old English ''torr'' is from Latin ''turris'' via Old French ''tor''. The Latin term together with Greek τύρσις was loaned from a pre-Indo-European Mediterranean languag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Former Radio Masts And Towers
A former is an object, such as a template, gauge or cutting die, which is used to form something such as a boat's hull. Typically, a former gives shape to a structure that may have complex curvature. A former may become an integral part of the finished structure, as in an aircraft fuselage, or it may be removable, being using in the construction process and then discarded or re-used. Aircraft formers Formers are used in the construction of aircraft fuselage, of which a typical fuselage has a series from the nose to the empennage, typically perpendicular to the longitudinal axis of the aircraft. The primary purpose of formers is to establish the shape of the fuselage and reduce the column length of stringers to prevent instability. Formers are typically attached to longerons, which support the skin of the aircraft. The "former-and-longeron" technique (also called stations and stringers) was adopted from boat construction, and was typical of light aircraft built until the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buildings And Structures Demolished In 1995
A building, or edifice, is an enclosed structure with a roof and walls standing more or less permanently in one place, such as a house or factory (although there's also portable buildings). Buildings come in a variety of sizes, shapes, and functions, and have been adapted throughout history for a wide number of factors, from building materials available, to weather conditions, land prices, ground conditions, specific uses, prestige, and aesthetic reasons. To better understand the term ''building'' compare the list of nonbuilding structures. Buildings serve several societal needs – primarily as shelter from weather, security, living space, privacy, to store belongings, and to comfortably live and work. A building as a shelter represents a physical division of the human habitat (a place of comfort and safety) and the ''outside'' (a place that at times may be harsh and harmful). Ever since the first cave paintings, buildings have also become objects or canvasses of much artistic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Masts
The tallest structure in the world is the Burj Khalifa skyscraper at . Listed are guyed masts (such as telecommunication masts), self-supporting towers (such as the CN Tower), skyscrapers (such as the Willis Tower), oil platforms, electricity transmission towers, and bridge support towers. This list is organized by absolute height. See List of tallest buildings and structures, List of tallest freestanding structures and List of tallest buildings and List of tallest towers for additional information about these types of structures. Terminology Terminological and listing criteria follow Council on Tall Buildings and Urban Habitat definitions. Guyed masts are differentiated from towers – the latter not featuring any guy wires or other support structures; and buildings are differentiated from towers – the former having at least 50% of occupiable floor space although both are self-supporting structures. List by height This list includes structures with a minimum height of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountainous
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher than a hill, typically rising at least 300 metres (1,000 feet) above the surrounding land. A few mountains are isolated summits, but most occur in mountain ranges. Mountains are formed through tectonic forces, erosion, or volcanism, which act on time scales of up to tens of millions of years. Once mountain building ceases, mountains are slowly leveled through the action of weathering, through slumping and other forms of mass wasting, as well as through erosion by rivers and glaciers. High elevations on mountains produce colder climates than at sea level at similar latitude. These colder climates strongly affect the ecosystems of mountains: different elevations have different plants and animals. Because of the less hospitable terrain and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shortwave
Shortwave radio is radio transmission using shortwave (SW) radio frequencies. There is no official definition of the band, but the range always includes all of the high frequency band (HF), which extends from 3 to 30 MHz (100 to 10 metres); above the medium frequency band (MF), to the bottom of the VHF band. Radio waves in the shortwave band can be reflected or refracted from a layer of electrically charged atoms in the atmosphere called the ionosphere. Therefore, short waves directed at an angle 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 can be used for communication over very long distances, in contrast to radio waves of higher frequency, which travel in straight lines (line-of-sight propagation) and are limited by the visual horizon, about 64 km (40 miles). Shortwave broadcasts of radio programs played an important role in the early days of rad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sendeanlage Bisamberg
The Sendeanlage Bisamberg ( Bisamberg transmission facility) was an Austrian medium wave transmission facility built in 1933 and demolished on February 24, 2010. The original transmitter was destroyed at the end of World War II, but was later rebuilt. It had two guyed steel framework masts, one with a height of 265 metres and another with a height of 120 metres. Both masts were insulated against ground. The higher mast, which was the tallest construction of Austria before demolition, was designed for use on 585 kHz, while the smaller one was designed for 1476 kHz. From January 1, 1995 to July 1, 1997, the installation was shut down, with the 1476 kHz transmitter being reactivated on July 1, 1997. The masts were demolished with controlled explosions on February 24, 2010; this decision by the city of Vienna was based on the fact that maintenance of the technologically obsolete masts as historical monuments would have been too costly. As of February 24, 20 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Österreichischer Rundfunk
('Austrian Broadcasting Corporation'; ORF) is an Austrian national public broadcaster. Funded from a combination of television licence fee revenue and limited on-air advertising, ORF is the dominant player in the Austrian broadcast media. Austria was the last country in continental Europe after Albania to allow nationwide private television broadcasting, although commercial TV channels from neighbouring Germany have been present in Austria on pay-TV and via terrestrial overspill since the 1980s. History of broadcasting in Austria The first unregulated test transmissions in Austria began on 1 April 1923 by Radio Hekaphon, run by the radio pioneer and enthusiast Oskar Czeija ( de; 1887–1958), who applied for a radio licence in 1921; first in his telephone factory in the Brigittenau district of Vienna, later in the nearby TGM technical college. On 2 September, it aired a first broadcast address by Austrian President Michael Hainisch (1858–1940). One year later, a power ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
