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Haganeyama Transmitter
Haganeyama Transmitter (はがね山標準電波送信所, ') is an LF-time signal transmitter at Fuji-cho, Saga-city, Saga-ken, Japan used for transmitting the time signal JJY on 60 kHz. The Haganeyama site is one of two JJY transmitters, another is the Otakadoyama site. Summy * NAME： NICT Haganeyama LF station * Location：Summit of Mt. Hagane, Fuji-cho, Saga-city, Saga-ken * Elevation：about 900m * Latitude：33°27'56.0"N * Longitude：130°10'32.0"E * License： NICT * Station purpose：Transmitting the official Japanese government frequency standards and time signal * Frequency form：250H A1B * Frequency：60kHz * Antenna power：50 kW（Antenna efficiency: about 45%） * Antenna form：Umbrella type 200m high * Operation time：continuously * Operation start：2001/10/01 * Range：About 1,000 km * Transmission method : See also * Otakadoyayama Transmitter Otakadoyayama Transmitter (おおたかどや山標準電波送信所, ') is an LF-time signal transmitte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otakadoyayama Transmitter
Otakadoyayama Transmitter (おおたかどや山標準電波送信所, ') is an LF-time signal transmitter at Tamura-City, Fukushima-ken, Japan used for transmitting the time signal JJY on 40 kHz. The Otakadoyama site is one of two JJY transmitters, another is the Haganeyama site. Summy * NAME： NICT Otakadoyayama LF station * Location：Summit of Mt. Otakadoya, Tamura-City, Fukushima-ken * Elevation：about 790m * Latitude：37°22'21.0"N * Longitude：140°50'56.0"E * License： NICT * Station purpose：Transmitting the official Japanese government frequency standards and time signal * Frequency form：250H A1B * Frequency：40kHz * Antenna power：50 kW（Antenna efficiency: about 45%） * Antenna form：Umbrella type 250m high * Operation time：continuously * Operation start：1999/06/01 * Range：About 1,000 km * Transmission method : See also * Haganeyama Transmitter Haganeyama Transmitter (はがね山標準電波送信所, ') is an LF-time signal transmitter a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JJY Radio Mast On Mount Hagane
JJY is the call sign of a low frequency time signal radio station located in Japan. The station broadcasts from two sites, one on Mount Otakadoya, near Fukushima, and the other on Mount Hagane, located on Kyushu Island. JJY is operated by the National Institute of Information and Communications Technology (NICT), an independent administrative institution affiliated with the Ministry of Internal Affairs and Communications of the Japanese government. Transmission sites The Mount Otakadoya site () is located at an elevation of 790 meters (2,590 ft) in Fukushima Prefecture. It broadcasts a 50 kW signal (13 kW ERP) on 40 kHz from an umbrella top-loading antenna situated 250 meters (820 ft) above the ground. In March 2011, it was powered down and evacuated due to its proximity to the Fukushima Daiichi nuclear disaster. It resumed broadcasting on April 21, unattended by staff. It went off air again temporarily on April 25 due to lightning, but has ever since been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
License
A license (or licence) is an official permission or permit to do, use, or own something (as well as the document of that permission or permit). A license is granted by a party (licensor) to another party (licensee) as an element of an agreement between those parties. In the case of a license issued by a government, the license is obtained by applying for it. In the case of a private party, it is by a specific agreement, usually in writing (such as a lease or other contract). The simplest definition is "A license is a promise not to sue," because a license usually either permits the licensed party to engage in an activity which is illegal, and subject to prosecution, without the license (e.g. fishing, driving an automobile, or operating a broadcast radio or television station), or it permits the licensed party to do something that would violate the rights of the licensing party (e.g. make copies of a copyrighted work), which, without the license, the licensed party could be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Watt
The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James Watt (1736–1819), an 18th-century Scottish inventor, mechanical engineer, and chemist who improved the Newcomen engine with his own steam engine in 1776. Watt's invention was fundamental for the Industrial Revolution. Overview When an object's velocity is held constant at one metre per second against a constant opposing force of one newton, the rate at which work is done is one watt. : \mathrm In terms of electromagnetism, one watt is the rate at which electrical work is performed when a current of one ampere (A) flows across an electrical potential difference of one volt (V), meaning the watt is equivalent to the volt-ampere (the latter unit, however, is used for a different quantity from the real power of an electrical circuit). : ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmitter Power Output
In radio transmission, transmitter power output (TPO) is the actual amount of power (in watts) of radio frequency (RF) energy that a transmitter produces at its output. This is not the amount of power that a radio station reports as its power, as in "we're 100,000 watts of rock 'n' roll", which is usually the effective radiated power (ERP). The ERP for VHF-/UHF-transmitters is normally more than the TPO, for LF-/MF-transmitters it has nearly the same value, while for VLF-transmitters it may be less. Signal formula The radio antenna's design "focuses" the signal toward the horizon, creating gain and increasing the ERP. There is also some loss (negative gain) from the feedline, which reduces some of the TPO to the antenna by both resistance and by radiating a small part of the signal. The basic equation relating transmitter to effective power is: ::TPO\ \times\ loss_\ \times\ gain_\ =\ ERP Note that in this formula the Antenna Gain is expressed with reference to a tuned dipole ( d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hertz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one hertz is the reciprocal of one second. It is named after Heinrich Rudolf Hertz (1857–1894), the first person to provide conclusive proof of the existence of electromagnetic waves. Hertz are commonly expressed in multiples: kilohertz (kHz), megahertz (MHz), gigahertz (GHz), terahertz (THz). Some of the unit's most common uses are in the description of periodic waveforms and musical tones, particularly those used in radio- and audio-related applications. It is also used to describe the clock speeds at which computers and other electronics are driven. The units are sometimes also used as a representation of the energy of a photon, via the Planck relation ''E'' = ''hν'', where ''E'' is the photon's energy, ''ν'' is its freq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Frequency
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upper limit of audio frequencies and the lower limit of infrared frequencies; these are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves. Different sources specify different upper and lower bounds for the frequency range. Electric current Electric currents that oscillate at radio frequencies (RF currents) have special properties not shared by direct current or lower audio frequency alternating current, such as the 50 or 60 Hz current used in electrical power distribution. * Energy from RF currents in conductors can radiate into space as electromagnetic waves ( radio waves). This is the basis of radio technology. * RF current does not penetrate deeply into electrical c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Types Of Radio Emissions
The International Telecommunication Union uses an internationally agreed system for classifying radio frequency signals. Each type of radio emission is classified according to its bandwidth, method of modulation, nature of the modulating signal, and type of information transmitted on the carrier signal. It is based on characteristics of the ''signal'', not on the transmitter used. An emission designation is of the form ''BBBB 123 45'', where ''BBBB'' is the bandwidth of the signal, ''1'' is a letter indicating the type of modulation used of the main carrier (not including any subcarriers which is why FM stereo is F8E and not D8E), ''2'' is a digit representing the type of modulating signal again of the main carrier, ''3'' is a letter corresponding to the type of information transmitted, ''4'' is a letter indicating the practical details of the transmitted information, and ''5'' is a letter that represents the method of multiplexing. The ''4'' and ''5'' fields are optional. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latitude
In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north pole, with 0° at the Equator. Lines of constant latitude, or ''parallels'', run east–west as circles parallel to the equator. Latitude and ''longitude'' are used together as a coordinate pair to specify a location on the surface of the Earth. On its own, the term "latitude" normally refers to the ''geodetic latitude'' as defined below. Briefly, the geodetic latitude of a point is the angle formed between the vector perpendicular (or ''normal'') to the ellipsoidal surface from the point, and the plane of the equator. Background Two levels of abstraction are employed in the definitions of latitude and longitude. In the first step the physical surface is modeled by the geoid, a surface which approximates the mean sea level over the ocean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longitude
Longitude (, ) is a geographic coordinate that specifies the east–west position of a point on the surface of the Earth, or another celestial body. It is an angular measurement, usually expressed in degrees and denoted by the Greek letter lambda (λ). Meridians are semicircular lines running from pole to pole that connect points with the same longitude. The prime meridian defines 0° longitude; by convention the International Reference Meridian for the Earth passes near the Royal Observatory in Greenwich, England on the island of Great Britain. Positive longitudes are east of the prime meridian, and negative ones are west. Because of the Earth's rotation, there is a close connection between longitude and time measurement. Scientifically precise local time varies with longitude: a difference of 15° longitude corresponds to a one-hour difference in local time, due to the differing position in relation to the Sun. Comparing local time to an absolute measure of time allows ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low Frequency
Low frequency (LF) is the ITU designation for radio frequencies (RF) in the range of 30–300 kHz. Since its wavelengths range from 10–1 km, respectively, it is also known as the kilometre band or kilometre wave. LF radio waves exhibit low signal attenuation, making them suitable for long-distance communications. In Europe and areas of Northern Africa and Asia, part of the LF spectrum is used for AM broadcasting as the "longwave" band. In the western hemisphere, its main use is for aircraft beacon, navigation (LORAN), information, and weather systems. A number of time signal broadcasts also use this band. Propagation Because of their long wavelength, low frequency radio waves can diffract over obstacles like mountain ranges and travel beyond the horizon, following the contour of the Earth. This mode of propagation, called ''ground wave'', is the main mode in the LF band. Ground waves must be vertically polarized (the electric field is vertical while the magnet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elevation
The elevation of a geographic location is its height above or below a fixed reference point, most commonly a reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational surface (see Geodetic datum § Vertical datum). The term ''elevation'' is mainly used when referring to points on the Earth's surface, while ''altitude'' or ''geopotential height'' is used for points above the surface, such as an aircraft in flight or a spacecraft in orbit, and '' depth'' is used for points below the surface. Elevation is not to be confused with the distance from the center of the Earth. Due to the equatorial bulge, the summits of Mount Everest and Chimborazo have, respectively, the largest elevation and the largest geocentric distance. Aviation In aviation the term elevation or aerodrome elevation is defined by the ICAO as the highest point of the landing area. It is often measured in feet and can be found in approach charts of the aerodrome. It is n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
