|
HBG (time Signal)
HBG was a low frequency time signal transmitter for the Swiss time reference system. It transmitted on 75 kHz with 20 kW power, and was located in Prangins, Switzerland. Due to the cost of urgently needed renovation for the ageing antennas, and the ease with which all existing users could switch to the DCF77 time signal, the Swiss Federal Government decided to shut down HBG at the end of 2011. HBG transmission ceased on New Year’s Day 2012 at 07:00:13.2 UTC. On 6 September 2012 at 12:02:00 UTC both antenna towers were demolished by controlled explosives. The HBG transmission format was very similar to DCF77. At the beginning of each second (with the exception of the 59th), the carrier signal was interrupted for a period of 0.1 s or 0.2 s, which corresponded to a binary "0" or "1". The transmission of the minute, hour, calendar date, day of the week, month and current year was achieved by means of a BCD code identical to that of DCF77. Like DCF77, the carrier was not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prangins
Prangins () is a municipality in the district of Nyon in the canton of Vaud in Switzerland. It is located on Lake Geneva. History Prangins is first mentioned around 1135-85 as ''Prengins''. Following the fall of the Second French Empire, Prince Napoléon Bonaparte and his wife, Princess Maria Clotilde of Savoy, resided in exile at Château de Prangins, where Charles I of Austria and his family would later take residence briefly, beginning 20 May 1919. Geography Prangins has an area, , of . Of this area, or 54.7% is used for agricultural purposes, while or 13.1% is forested. Of the rest of the land, or 31.3% is settled (buildings or roads), or 0.7% is either rivers or lakes and or 0.2% is unproductive land.Swiss Federal Statistical Office-Land Use Statistics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swiss Federal Office Of Metrology
{{gov-stub ...
The Federal Institute of Metrology (METAS) is the Swiss national metrology organization. It is part of the Federal Department of Justice and Police. References External links * Standards organisations in Switzerland Federal Department of Justice and Police Metrology Metrology is the scientific study of measurement. It establishes a common understanding of units, crucial in linking human activities. Modern metrology has its roots in the French Revolution's political motivation to standardise units in Fran ... [...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] |
Time Signal
A time signal is a visible, audible, mechanical, or electronic signal used as a reference to determine the time of day. Church bells or voices announcing hours of prayer gave way to automatically operated chimes on public clocks; however, audible signals (even signal guns) have limited range. Busy seaports used a visual signal, the dropping of a ball, to allow mariners to check the chronometers used for navigation. The advent of electrical telegraphs allowed widespread and precise distribution of time signals from central observatories. Railways were among the first customers for time signals, which allowed synchronization of their operations over wide geographic areas. Dedicated radio time signal stations transmit a signal that allows automatic synchronization of clocks, and commercial broadcasters still include time signals in their programming. Today, global navigation satellite systems (GNSS) radio signals are used to precisely distribute time signals over much of the world ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmitter
In electronics and telecommunications, a radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna (radio), antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the Antenna (radio), antenna. When excited by this alternating current, the antenna radiates radio waves. Transmitters are necessary component parts of all electronic devices that communicate by radio communication, radio, such as radio broadcasting, radio and television broadcasting stations, cell phones, walkie-talkies, Wireless LAN, wireless computer networks, Bluetooth enabled devices, garage door openers, two-way radios in aircraft, ships, spacecraft, radar sets and navigational beacons. The term ''transmitter'' is usually limited to equipment that generates radio waves for Communication engineering, communication purposes; or radiolocation, such as radar and navigational transmitters. Generators of radio waves for heatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DCF77
DCF77 is a German longwave time signal and standard-frequency radio station. It started service as a standard-frequency station on 1 January 1959. In June 1973 date and time information was added. Its primary and backup transmitter are located at in Mainflingen, about 25 km south-east of Frankfurt am Main, Germany. The transmitter generates a nominal power of 50 kW, of which about 30 to 35 kW can be radiated via a T-antenna. DCF77 is controlled by the ''Physikalisch-Technische Bundesanstalt'' (PTB), Germany's national physics laboratory and transmits in continuous operation (24 hours). It is operated by ''Media Broadcast GmbH'' (previously a subsidiary of ''Deutsche Telekom AG''), on behalf of the PTB. With Media Broadcast GmbH, a temporal transmission availability of at least 99.7% per year or under 26.28 hours of annual downtime has been agreed upon. Most service interruptions are short-term disconnections of under two minutes. Longer lasting transmission servi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carrier Wave
In telecommunications, a carrier wave, carrier signal, or just carrier, is a waveform (usually sinusoidal) that is modulated (modified) with an information-bearing signal for the purpose of conveying information. This carrier wave usually has a much higher frequency than the input signal does. The purpose of the carrier is usually either to transmit the information through space as an electromagnetic wave (as in radio communication), or to allow several carriers at different frequencies to share a common physical transmission medium by frequency division multiplexing (as in a cable television system). The term originated in radio communication, where the carrier wave creates the waves which carry the information (modulation) through the air from the transmitter to the receiver. The term is also used for an unmodulated emission in the absence of any modulating signal. In music production, carrier signals can be controlled by a modulating signal to change the sound property of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BCD Code
In computing and electronic systems, binary-coded decimal (BCD) is a class of binary encodings of decimal numbers where each digit is represented by a fixed number of bits, usually four or eight. Sometimes, special bit patterns are used for a sign or other indications (e.g. error or overflow). In byte-oriented systems (i.e. most modern computers), the term ''unpacked'' BCD usually implies a full byte for each digit (often including a sign), whereas ''packed'' BCD typically encodes two digits within a single byte by taking advantage of the fact that four bits are enough to represent the range 0 to 9. The precise 4-bit encoding, however, may vary for technical reasons (e.g. Excess-3). The ten states representing a BCD digit are sometimes called '' tetrades'' (for the nibble typically needed to hold them is also known as a tetrade) while the unused, don't care-states are named , ''pseudo-decimals'' or ''pseudo-decimal digits''. BCD's main virtue, in comparison to binary positi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carrier Frequency
In telecommunications, a carrier wave, carrier signal, or just carrier, is a waveform (usually sinusoidal) that is modulated (modified) with an information-bearing signal for the purpose of conveying information. This carrier wave usually has a much higher frequency than the input signal does. The purpose of the carrier is usually either to transmit the information through space as an electromagnetic wave (as in radio communication), or to allow several carriers at different frequencies to share a common physical transmission medium by frequency division multiplexing (as in a cable television system). The term originated in radio communication, where the carrier wave creates the waves which carry the information (modulation) through the air from the transmitter to the receiver. The term is also used for an unmodulated emission in the absence of any modulating signal. In music production, carrier signals can be controlled by a modulating signal to change the sound property of an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time Signal Radio Stations
Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, to compare the duration of events or the intervals between them, and to quantify rates of change of quantities in material reality or in the conscious experience. Time is often referred to as a fourth dimension, along with three spatial dimensions. Time has long been an important subject of study in religion, philosophy, and science, but defining it in a manner applicable to all fields without circularity has consistently eluded scholars. Nevertheless, diverse fields such as business, industry, sports, the sciences, and the performing arts all incorporate some notion of time into their respective measuring systems. 108 pages. Time in physics is operationally defined as "what a clock reads". The physical nature of time is addressed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Defunct Radio Stations
{{Disambiguation ...
Defunct (no longer in use or active) may refer to: * ''Defunct'' (video game), 2014 * Zombie process or defunct process, in Unix-like operating systems See also * * :Former entities * End-of-life product * Obsolescence Obsolescence is the state of being which occurs when an object, service, or practice is no longer maintained or required even though it may still be in good working order. It usually happens when something that is more efficient or less risky r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
