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Radio VNG
Radio VNG was Australia's national time signal service. It was inaugurated by the Australian Post Office at Lyndhurst, Victoria on 21 September 1964, although a predecessor service using the callsign VLX had begun in March 1946 alongside shortwave radio station VLR. From 1964 until 1987, Radio VNG transmitted on 4.5, 7.5 and 12 MHz from the Lyndhurst transmitters. After 1987 it relocated to Shanes Park, NSW, and transmitted on 2.5, 5, 8.638, 12.984, and 16 MHz. Signal properties Radio VNG broadcast time in binary coded decimal, during seconds 21–58. It also broadcast DUT-1 information during seconds 1-16. Tones were usually of 1 kHz. Encoding details are described in the VNG Leaflet (see Further Reading). Radio VNG also broadcast a spoken time signal every 15 minutes. The exact words in earlier years were: "This is VNG Lyndhurst, Victoria, Australia on 4.5, 7.5 or 12 MHz. VNG is a standard frequency and time signal service of the Australian Telecommunications Com ... [...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] |
Postmaster-General's Department
The Postmaster-General's Department (PMG) was a department of the Australian federal government, established at Federation in 1901, whose responsibilities included the provision of postal and telegraphic services throughout Australia. It was abolished in December 1975 and replaced by the Postal and Telecommunications Department. Two separate legal entities had been established in July 1975 to take over the department's operations: Telecom Australia (colloquially "Telecom"; later became Telstra) and Australia Post. History The Postmaster-General's Department was created in 1901 to take over all postal and telegraphy services in Australia from the states and administer them on a national basis. The department was administered by the postmaster-general. The first permanent secretary of the department was Sir Robert Townley Scott, who held office from 1 July 1901 until his retirement on 31 December 1910. In its first 25 years, the department grew from 6,000 to 10,000 off ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyndhurst, Victoria
Lyndhurst is a suburb in Melbourne, Victoria, Australia, 36 km south-east of Melbourne's Central Business District, located within the Cities of Casey and Greater Dandenong local government areas. Lyndhurst recorded a population of 8,926 at the 2021 census. Lyndhurst Post Office opened on 1 January 1867 and closed in 1976. After the Bracks government's decisions to abandon plans for a toxic waste dump near Mildura, the continued use of the existing Lyndhurst facility was part of the replacement plan. The Casey side of Lyndhurst lies inside the Urban Growth Boundary, and the development phase is almost complete. The Greater Dandenong side (to the west of the Western Port Highway) is outside the Urban Growth Boundary and is semi rural, and forms part of the South Eastern green wedge. In 2009 the Victorian Department of Education and Early Childhood Development purchased a 3.5-hectare site within Marriott Waters and earmarked the site for Lyndhurst Primary School. The Pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Victoria (Australia)
Victoria is a state in southeastern Australia. It is the second-smallest state with a land area of , the second most populated state (after New South Wales) with a population of over 6.5 million, and the most densely populated state in Australia (28 per km2). Victoria is bordered by New South Wales to the north and South Australia to the west, and is bounded by the Bass Strait to the south (with the exception of a small land border with Tasmania located along Boundary Islet), the Great Australian Bight portion of the Southern Ocean to the southwest, and the Tasman Sea (a marginal sea of the South Pacific Ocean) to the southeast. The state encompasses a range of climates and geographical features from its temperate coastal and central regions to the Victorian Alps in the northeast and the semi-arid north-west. The majority of the Victorian population is concentrated in the central-south area surrounding Port Phillip Bay, and in particular within the metropolit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
QSL Card
A QSL card is a written confirmation of either a two-way radiocommunication between two amateur radio or citizens band stations; a one-way reception of a signal from an AM radio, FM radio, television or shortwave broadcasting station; or the reception of a two-way radiocommunication by a third party listener. A typical QSL card is the same size and made from the same material as a typical postcard, and most are sent through the mail as such. QSL card derived its name from the Q code "QSL". A Q code message can stand for a statement or a question (when the code is followed by a question mark). In this case, 'QSL?' (note the question mark) means "Do you confirm receipt of my transmission?" while 'QSL' (without a question mark) means "I confirm receipt of your transmission." History During the early days of radio broadcasting, the ability for a radio set to receive distant signals was a source of pride for many consumers and hobbyists. Listeners would mail "reception reports" to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Coded Decimal
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 pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DUT (time)
DUT1 (sometimes also written DUT) is a time correction equal to the difference between Universal Time (UT1), which is defined by Earth's rotation, and Coordinated Universal Time (UTC), which is defined by a network of precision atomic clocks. :DUT1 = UT1 − UTC UTC is maintained via leap seconds, such that DUT1 remains within the range −0.9 s < DUT1 < +0.9 s. The reason for this correction is partly that the rate of rotation of the Earth is not constant, due to tidal braking and the redistribution of mass within the Earth, including its oceans and atmosphere, and partly because the second, SI second (as now used for UTC) was, when adopted, a little shorter than the current value of the second of mean solar time. Daily observed values of DUT1 for the past week, and daily forecast values for the coming year, are published by IERS] Bullet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australian Telecommunications Commission
Telstra Group Limited is an Australian telecommunications company that builds and operates telecommunications networks and markets voice, mobile, internet access, pay television and other products and services. It is a member of the S&P/ASX 20 and Australia's largest telecommunications company by market share. Telstra is the largest wireless carrier in Australia, with 18.8 million subscribers as of 2020. Telstra has a long history in Australia, originating together with Australia Post as the Postmaster-General's Department upon federation in 1901. Telstra has transitioned from a state-owned enterprise to a fully privatised company and has recently focused on diversified products and emerging technologies. History Australia's telecommunications services were originally controlled by the Postmaster-General's Department (PMG), formed in 1901 as a result of Australian Federation. Prior to 1901, telecommunications were administered by each colony. On 1 July 1975, separate c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leap Second
A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC), to accommodate the difference between precise time (International Atomic Time (TAI), as measured by atomic clocks) and imprecise observed solar time (UT1), which varies due to irregularities and long-term slowdown in the Earth's rotation. The UTC time standard, widely used for international timekeeping and as the reference for civil time in most countries, uses TAI and consequently would run ahead of observed solar time unless it is reset to UT1 as needed. The leap second facility exists to provide this adjustment. The leap second was introduced in 1972 and since then 27 leap seconds have been added to UTC. Because the Earth's rotation speed varies in response to climatic and geological events, UTC leap seconds are irregularly spaced and unpredictable. Insertion of each UTC leap second is usually decided about six months in advance by the International Earth Rotation and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commonwealth Of Australia
Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. With an area of , Australia is the largest country by area in Oceania and the world's sixth-largest country. Australia is the oldest, flattest, and driest inhabited continent, with the least fertile soils. It is a megadiverse country, and its size gives it a wide variety of landscapes and climates, with deserts in the centre, tropical rainforests in the north-east, and mountain ranges in the south-east. The ancestors of Aboriginal Australians began arriving from south east Asia approximately 65,000 years ago, during the last ice age.religious_traditions_in_the_world._Australia's_history_of_Australia.html" ;"title="The_Dreaming.html" ;"title="Aboriginal_Art.html" "title="he Story of Australia's People, Volume 1: The Rise and Fall of Ancient Australia, Penguin Books Australia Ltd., Vic., ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BPM (time Service)
BPM is the call sign of the official short-wave time signal service of the People's Republic of China, operated by the Chinese Academy of Sciences, broadcasting from CAS's National Time Service Center in Pucheng County, Shaanxi at , roughly 70 km northeast of Lintong, along with NTSC's long-wave time signal BPL on 100 kHz. BPM is broadcast at 2.5, 5.0, 10.0, and 15.0 MHz, the same frequencies as WWV and WWVH, following the schedule listed below: Transmission format BPM transmits different signals on a half-hour schedule, modulated with 1 kHz audio tones to provide second and minute ticks: BPM is idiosyncratic in that it transmits UT1 Universal Time (UT or UT1) is a time standard based on Earth's rotation. While originally it was mean solar time at 0° longitude, precise measurements of the Sun are difficult. Therefore, UT1 is computed from a measure of the Earth's angle with ... time between minutes 25 through to 29 and 55 through to 59, which creates an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WWVH
WWVH is the callsign of the U.S. National Institute of Standards and Technology's shortwave radio time signal station located at the Barking Sands Missile Range, in Kekaha, on the island of Kauai in the state of Hawaii. WWVH is the Pacific sister station to WWV, and has a similar broadcast format. Like WWV, WWVH's main function is the dissemination of official U.S. Government time, through exactly the same methods as found on WWV's signal. To minimize interference with the WWV broadcasts on the same frequencies, WWVH's broadcasts on 5, 10 and 15 MHz are directional, pointed primarily west. Despite this strategy, in certain places, particularly on the west coast of North America; and at certain times, due to ionospheric conditions, the listener can actually hear both WWV and WWVH on the same frequency at the same time. The information modulated on the carrier is modified to reduce confusion if both are received simultaneously. In particular, voice announcements on on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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