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Racon
Radar beacon (short: racon) is – according to ''article 1.103'' of the International Telecommunication Union's (ITU) ITU Radio Regulations (RR) – defined as "A transmitter-receiver associated with a fixed navigational mark which, when triggered by a radar, automatically returns a distinctive signal which can appear on the display of the triggering radar, providing range, bearing and identification information." Each ''station'' (transmitter-receiver, transceiver or transponder) shall be classified by the ''service'' in which it operates permanently or temporarily. Principle of operation When a racon receives a radar pulse, it responds with a signal on the same frequency which puts an image on the radar display. This takes the form of a short line of dots and dashes forming a Morse character radiating away from the location of the beacon on the normal plan position indicator radar display. The length of the line usually corresponds to the equivalent of a few nautical mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Racon Signal
Radar beacon (short: racon) is – according to ''article 1.103'' of the International Telecommunication Union's (ITU) ITU Radio Regulations (RR) – defined as "A transmitter-receiver associated with a fixed navigational mark which, when triggered by a radar, automatically returns a distinctive signal which can appear on the display of the triggering radar, providing range, bearing and identification information." Each ''station'' (transmitter-receiver, transceiver or transponder) shall be classified by the ''service'' in which it operates permanently or temporarily. Principle of operation When a racon receives a radar pulse, it responds with a signal on the same frequency which puts an image on the radar display. This takes the form of a short line of dots and dashes forming a Morse character radiating away from the location of the beacon on the normal plan position indicator radar display. The length of the line usually corresponds to the equivalent of a few nautical mile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Racon Beacon Setup
Radar beacon (short: racon) is – according to ''article 1.103'' of the International Telecommunication Union's (ITU) ITU Radio Regulations (RR) – defined as "A transmitter-receiver associated with a fixed navigational mark which, when triggered by a radar, automatically returns a distinctive signal which can appear on the display of the triggering radar, providing range, bearing and identification information." Each ''station'' (transmitter-receiver, transceiver or transponder) shall be classified by the ''service'' in which it operates permanently or temporarily. Principle of operation When a racon receives a radar pulse, it responds with a signal on the same frequency which puts an image on the radar display. This takes the form of a short line of dots and dashes forming a Morse character radiating away from the location of the beacon on the normal plan position indicator radar display. The length of the line usually corresponds to the equivalent of a few nautical mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RACON
Radar beacon (short: racon) is – according to ''article 1.103'' of the International Telecommunication Union's (ITU) ITU Radio Regulations (RR) – defined as "A transmitter-receiver associated with a fixed navigational mark which, when triggered by a radar, automatically returns a distinctive signal which can appear on the display of the triggering radar, providing range, bearing and identification information." Each ''station'' (transmitter-receiver, transceiver or transponder) shall be classified by the ''service'' in which it operates permanently or temporarily. Principle of operation When a racon receives a radar pulse, it responds with a signal on the same frequency which puts an image on the radar display. This takes the form of a short line of dots and dashes forming a Morse character radiating away from the location of the beacon on the normal plan position indicator radar display. The length of the line usually corresponds to the equivalent of a few nautical mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouse
A lighthouse is a tower, building, or other type of physical structure designed to emit light from a system of lamps and lenses and to serve as a beacon for navigational aid, for maritime pilots at sea or on inland waterways. Lighthouses mark dangerous coastlines, hazardous shoals, reefs, rocks, and safe entries to harbors; they also assist in aerial navigation. Once widely used, the number of operational lighthouses has declined due to the expense of maintenance and has become uneconomical since the advent of much cheaper, more sophisticated and effective electronic navigational systems. History Ancient lighthouses Before the development of clearly defined ports, mariners were guided by fires built on hilltops. Since elevating the fire would improve the visibility, placing the fire on a platform became a practice that led to the development of the lighthouse. In antiquity, the lighthouse functioned more as an entrance marker to ports than as a warning signal for reef ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Navigational Mark
A sea mark, also seamark and navigation mark, is a form of aid to navigation and pilotage that identifies the approximate position of a maritime channel, hazard, or administrative area to allow boats, ships, and seaplanes to navigate safely. There are three types of sea mark: beacons (fixed to the seabed or on shore), buoys (consisting of a floating object that is usually anchored to a specific location on the bottom of the sea or to a submerged object) and a type of cairn built on a submerged rock/object, especially in calmer waters. Sea marks are used to indicate channels, dangerous rocks or shoals, mooring positions, areas of speed limits, traffic separation schemes, submerged shipwrecks, and for a variety of other navigational purposes. Some are only intended to be visible in daylight ('' daymarks''), others have some combination of lights, reflectors, fog bells, foghorns, whistles and radar reflectors to make them usable at night and in conditions of reduced visibility. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transponder
In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a flight transponder is an automated transceiver in an aircraft that emits a coded identifying signal in response to an interrogating received signal. In a communications satellite, a satellite transponder receives signals over a range of uplink frequencies, usually from a satellite ground station; the transponder amplifies them, and re-transmits them on a different set of downlink frequencies to receivers on Earth, often without changing the content of the received signal or signals. Satellite/broadcast communications A communications satellite’s channels are called transponders because each is a separate transceiver or repeater. With digital video data compression and multiplexing, several video and audio channels may travel through a single t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ITU Radio Regulations
The ITU Radio Regulations (short: RR) is a basic document of the International Telecommunication Union (ITU) that regulates on law of nations scale radiocommunication services and the utilisation of radio frequencies. It is the supplementation to the ITU Constitution and Convention and in line with the ITU International Telecommunication Regulations (ITR). The ITU RR comprise and regulate the part of the allocated electromagnetic spectrum (also: radio frequency spectrum) from 9 kHz to 275 GHz. Structure The current approved version of the ITU Radio Regulations (addition 2012) is structured as follows: Volume 1 – Articles * CHAPTER I – Terminology and technical characteristics **Section I – General terms (article 1.1-1.15) **Section II – Specific terms related to frequency management (article 1.16-1.18) **Section III – Radiocommunication services (article 1.19-1.60) **Section IV – Radio stations and systems (article 1.61-1.115) **Section V – Operatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ramark
{{Unreferenced, date=December 2009 A ramark, acronym for radar marker, was a type of radar beacon used to mark maritime navigational hazards. Ramarks are no longer in use. They were wide-band beacons which transmitted either continuously or periodically on the radar bands. The transmission formed a line of Morse characters on a plan position indicator A plan position indicator (PPI) is a type of radar display that represents the radar antenna in the center of the display, with the distance from it and height above ground drawn as concentric circles. As the radar antenna rotates, a radial trac ... (PPI) radar display which radiated from the centre of the display to its edge, hence giving only a bearing, as opposed to radar beacon (racons) which give bearing and position. Periodic transmissions every few seconds are usually used so that important radar targets behind the ramark beacon are not masked by the Morse characters. Ramark beacons are less commonly used than racons wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battery (electricity)
An electric battery is a source of electric power consisting of one or more electrochemical cells with external connections for powering electrical devices. When a battery is supplying power, its positive terminal is the cathode and its negative terminal is the anode. The terminal marked negative is the source of electrons that will flow through an external electric circuit to the positive terminal. When a battery is connected to an external electric load, a redox reaction converts high-energy reactants to lower-energy products, and the free-energy difference is delivered to the external circuit as electrical energy. Historically the term "battery" specifically referred to a device composed of multiple cells; however, the usage has evolved to include devices composed of a single cell. Primary (single-use or "disposable") batteries are used once and discarded, as the electrode materials are irreversibly changed during discharge; a common example is the alkaline battery use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sevenstones Lightship
''Sevenstones'' Lightship is a lightvessel station off the Seven Stones Reef which is nearly to the west-north-west (WNW) of Land's End, Cornwall, and east-north-east (ENE) of the Isles of Scilly. The reef has been a navigational hazard to shipping for centuries with seventy-one named wrecks and an estimated two hundred shipwrecks overall, the most infamous being the oil tanker ''Torrey Canyon'' on 18 March 1967. The rocks are only exposed at half tide. Since it was not feasible to build a lighthouse, a lightvessel was provided by Trinity House. The first was moored near the reef on 20 August 1841 and exhibited its first light on 1 September 1841. She is permanently anchored in and is north-east (NE) of the reef. Since 1987, the Sevenstones Lightship has been automated and unmanned. The Seven Stones lightvessel also acts as an automatic weather station. A series of Trinity House lightships stationed near the Sevenstones Reef have measured significant wave heights (''Hs'' o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Duty Cycle
A duty cycle or power cycle is the fraction of one period in which a signal or system is active. Duty cycle is commonly expressed as a percentage or a ratio. A period is the time it takes for a signal to complete an on-and-off cycle. As a formula, a duty cycle (%) may be expressed as: :D = \frac \times 100\% Equally, a duty cycle (ratio) may be expressed as: :D = \frac where D is the duty cycle, PW is the pulse width (pulse active time), and T is the total period of the signal. Thus, a 60% duty cycle means the signal is on 60% of the time but off 40% of the time. The "on time" for a 60% duty cycle could be a fraction of a second, a day, or even a week, depending on the length of the period. Duty cycles can be used to describe the percent time of an active signal in an electrical device such as the power switch in a switching power supply or the firing of action potentials by a living system such as a neuron. The duty factor for periodic signal expresses the same notion, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotland, Wales and Northern Ireland. The United Kingdom includes the island of Great Britain, the north-eastern part of the island of Ireland, and many List of islands of the United Kingdom, smaller islands within the British Isles. Northern Ireland shares Republic of Ireland–United Kingdom border, a land border with the Republic of Ireland; otherwise, the United Kingdom is surrounded by the Atlantic Ocean, the North Sea, the English Channel, the Celtic Sea and the Irish Sea. The total area of the United Kingdom is , with an estimated 2020 population of more than 67 million people. The United Kingdom has evolved from a series of annexations, unions and separations of constituent countries over several hundred years. The Treaty of Union between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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