atomic clock - Article Index

Encyclopedia - Time Signal: Encyclopedia Ii - Time Signal - Audible And Visible Time Signals
One sort of public time signal is, of course, a striking clock. These clocks, however, are only as good as the clockwork that activates t...   » Read the article

Encyclopedia - Radio Clock: Encyclopedia Ii - Radio Clock - Other Access
In the era when national broadcasting networks operated over point-to-point terrestrial microwave links, the time announcements were very...   » Read the article

Encyclopedia - Second: Encyclopedia - Second
The second (symbol: s) is the SI base unit of time. It is often abbreviated sec. in non-SI usage. Second - Definition. The second is the...   » Read the article

Encyclopedia - Hebrew Calendar: Encyclopedia - Hebrew Calendar
The Hebrew calendar (Hebrew: הלוח העברי) or Jewish calendar is the annual calendar used in Judaism. It determines the dates of t...   » Read the article

Encyclopedia - Clock: Encyclopedia - Clock
A clock (from the Latin cloca, "bell") is an instrument for measuring time. A clock is usually a physical instrument; an especially accur...   » Read the article

Encyclopedia - Radio Clock: Encyclopedia Ii - Radio Clock - Operation
Radio clocks depend on time signal radio stations, which usually have the following attributes: they refer their broadcast frequency to ...   » Read the article

Encyclopedia - Celestial Navigation: Encyclopedia - Celestial Navigation
Celestial navigation, also known as astronavigation, is a position fixing technique that was the first system devised to help sailors loc...   » Read the article

Encyclopedia - Braunschweig: Encyclopedia - Braunschweig
Braunschweig [ˈbraunʃvaik] (English Brunswick) is a city of 245,500 people (as of December 31, 2004), located in Lower Saxony, Germany...   » Read the article

Encyclopedia - Very Long Baseline Interferometry: Encyclopedia - Very Long Baseline Interferometry
Very Long Baseline Interferometry (VLBI) is a type of interferometry in which the data received at each antenna in the array is paired wi...   » Read the article

Encyclopedia - Radio Clock: Encyclopedia Ii - Radio Clock - Gps Clocks
Many modern radio clocks use the GPS satellite positioning system to provide more accurate time than can be obtained from these terrestri...   » Read the article

Encyclopedia - Time Signal: Encyclopedia Ii - Time Signal - Electrical And Electronic Time Signals
Standard time came into existence in the United States on November 18, 1883. Earlier, on October 11, 1883, the General Time Convention, f...   » Read the article

Encyclopedia - Maser: Encyclopedia Ii - Maser - Uses
Masers serve as high precision frequency references. These "atomic frequency standards" are one form of atomic clock. They are also used ...   » Read the article

Encyclopedia - Doctor Who 1996: Encyclopedia Ii - Doctor Who 1996 - Plot
On the planet Skaro, the renegade Time Lord known as the Master is put on trial by the Daleks, and executed. His last wish is for his rem...   » Read the article

Encyclopedia - Interrupt: Encyclopedia Ii - Interrupt - Overview
Interrupts originated as a way to avoid wasting the processors valuable time in polling loops, waiting for external events. Instead, an i...   » Read the article

Encyclopedia - G-shock: Encyclopedia Ii - G-shock - History
"In 1981 Casio began designing a new kind of wristwatch, based on the "Triple Ten" concept: A minimum of 10 year battery life, 10 bar wat...   » Read the article

Encyclopedia - Music Radio: Encyclopedia Ii - Music Radio - Music Formats
Some well-known music-radio formats are Top 40, Freeform Rock and AOR (Album Oriented Rock). It turns out that most other stations (such ...   » Read the article

Encyclopedia - Satellite Navigation System: Encyclopedia Ii - Satellite Navigation System - History And Theory
An early predecessor were the ground based LORAN and Omega systems, which used terrestrial longwave radio transmitters instead of satelli...   » Read the article

Encyclopedia - Louis Essen: Encyclopedia Ii - Louis Essen - Later Life
Essen spent all his working life at the National Physical Laboratory but caused some embarrassment to his employers in (1971) when he pub...   » Read the article

Encyclopedia - Transmitter: Encyclopedia Ii - Transmitter - Electromagnetic Concepts
In principle any conductor (wire) carrying an alternating current will radiate a radio signal. Thus a basic transmitter is just an oscill...   » Read the article

Encyclopedia - Clock: Encyclopedia Ii - Clock - History
The clock is one of the oldest human inventions. In principle, it requires no more than some physical process which will proceed at a kno...   » Read the article

Encyclopedia - Navigation: Encyclopedia Ii - Navigation - Western Navigation
Navigation - Modern methods. There are several different branches of navigation, including but not limited to: celestial navigation - ...   » Read the article

Encyclopedia - National Research Council Of Canada: Encyclopedia Ii - National Research Council Of Canada - Employment
The National Research Council employs close to 4,000 people across Canada. Like all government agencies, it is subject to strict hiring r...   » Read the article

Encyclopedia - Teddington: Encyclopedia Ii - Teddington - Local Geography
Teddington - Nearest places. Twickenham Ham Petersham Hampton Norbiton Surbiton Feltham Strawberry Hill Teddington - Nearest railway...   » Read the article

Encyclopedia - Clock: Encyclopedia Ii - Clock - History
The clock is one of the oldest human inventions. Vitruvius reported that the ancient Egyptians used clepsydras, a time mechanism run by f...   » Read the article

Encyclopedia - Interrupt: Encyclopedia Ii - Interrupt - Overview
Interrupts originated as a way to avoid wasting the processor's valuable time in polling loops, waiting for external events. Instead, an ...   » Read the article

Encyclopedia - Celestial Navigation: Encyclopedia Ii - Celestial Navigation - Practical Navigation
Practical celestial navigation usually requires a chronometer to measure time, a sextant to measure the angles, an almanac giving angular...   » Read the article

Encyclopedia - Time In New Zealand: Encyclopedia Ii - Time In New Zealand - Daylight Saving Time
The Summer Time Act 1929, which was later replaced by the Time Act 1974, gives power to the Governor-General to declare a period which Da...   » Read the article

Encyclopedia - Second: Encyclopedia Ii - Second - Explanation
The factor of 60 comes from the Babylonians who used factors of 60 in their counting system. The hour had previously been defined by the ...   » Read the article

Encyclopedia - Braunschweig: Encyclopedia Ii - Braunschweig - History
The date and circumstances of the town's foundation are unknown. Tradition maintains that Braunschweig was created through the merger of ...   » Read the article

Encyclopedia - Smpte Time Code: Encyclopedia Ii - Smpte Time Code - Longitudinal Timecode Data Format
The basic format is an 80-bit code that gives the time of day to the second, and the frame number within the second. The bits of the long...   » Read the article

Encyclopedia - Hebrew Calendar: Encyclopedia Ii - Hebrew Calendar - History
Hebrew calendar - Biblical period. Jews have been using a lunisolar calendar since Biblical times, but originally referred to the month...   » Read the article

Encyclopedia - Leap Second: Encyclopedia Ii - Leap Second - Reason For Leap Seconds
Leap seconds are necessary because time is measured utilizing stable atomic clocks (TAI or International Atomic Time), whereas the rotati...   » Read the article

Encyclopedia - Digital Clock: Encyclopedia Ii - Digital Clock - Displays
To represent the time, most digital clocks use a seven-segment LED or LCD display for each of four digits. They generally also include ot...   » Read the article

Encyclopedia - Interrupt: Encyclopedia Ii - Interrupt - Overview
Interrupts originated as a way to avoid wasting the processors valuable time in polling loops, waiting for external events. Instead, an i...   » Read the article

Encyclopedia - Time In New Zealand: Encyclopedia Ii - Time In New Zealand - History
On November 2, 1868, New Zealand officially adopted a standard time to be observed nationally, and was perhaps the first country to do so...   » Read the article

Encyclopedia - Smpte Time Code: Encyclopedia Ii - Smpte Time Code - Basic Concepts
SMPTE timecodes contains binary coded decimal hour:minute:second:frame identification and 32 bits for use by users. There are also drop-f...   » Read the article

Encyclopedia - Transmitter: Encyclopedia Ii - Transmitter - Transmitters In Culture
Some cities in Europe, like Muehlacker, Ismaning, Langenberg, Kalundborg, Hoerby and Allouis became famous as sites of powerful transmitt...   » Read the article

Encyclopedia - Transmitter: Encyclopedia Ii - Transmitter - Broadcasting
In broadcasting, the part which contains the oscillator, modulator, and sometimes audio processor, is called the exciter. Confusingly, th...   » Read the article

Encyclopedia - Interrupt: Encyclopedia Ii - Interrupt - Typical Uses
Typical interrupt uses include the following: system timers, disks IO, power-off signals, and traps. Other interrupts exist to transfer d...   » Read the article

Encyclopedia - G-shock: Encyclopedia Ii - G-shock - Today
"G"s have evolved remarkably since 1981. There now exists a manifold variation of G-Shocks, with atomic clock synchronization and Tough S...   » Read the article

Encyclopedia - Doctor Who 1996: Encyclopedia Ii - Doctor Who 1996 - Controversy
This television movie has caused controversy within Doctor Who fandom, with some fans charging that it violates canon in several areas. S...   » Read the article

Encyclopedia - Smpte Time Code: Encyclopedia Ii - Smpte Time Code - Studio Operations And Master Clocks
In studio operations, longitudinal timecode is generated by the studio master sync generator, and distributed from a central point. Centr...   » Read the article

Encyclopedia - Smpte Time Code: Encyclopedia Ii - Smpte Time Code - Drop Frame Timecode
Drop frame timecode dates to a compromise invented when color NTSC video was invented. Basically, the NTSC re-designers wanted to retain ...   » Read the article

Encyclopedia - Transmitter: Encyclopedia Ii - Transmitter - Planning
As in any costly undertaking, the planning of a high power transmitter site requires great care. This begins with the location. A minimum...   » Read the article

Encyclopedia - Clock: Encyclopedia Ii - Clock - Types
There are two major types of clocks. Clock - Analog clocks. Analog clocks may be mechanical or have a quartz movement. A clock face is ...   » Read the article

Encyclopedia - Clock: Encyclopedia Ii - Clock - Purposes
Clocks are in homes and offices; smaller ones (watches) are carried; larger ones are in public places, e.g. a train station or church. A ...   » Read the article

Encyclopedia - Smpte Time Code: Encyclopedia Ii - Smpte Time Code - Discontinuous Timecode And Flywheel Processing
Timecodes are generated as a continuous stream of sequential data values. In some applications 'wall clock' time is used, in others the t...   » Read the article

Encyclopedia - Navigation: Encyclopedia Ii - Navigation - Polynesian Navigation
The Polynesian navigators routinely crossed thousands of miles of open ocean, to tiny inhabited islands, using only their own senses and ...   » Read the article

Encyclopedia - Hebrew Calendar: Encyclopedia Ii - Hebrew Calendar - Accuracy
The average length of the month assumed by the calendar is correct within a fraction of a second (although individual months may be a few...   » Read the article

Encyclopedia - Interrupt: Encyclopedia Ii - Interrupt - Typical Uses
Typical interrupt uses include the following: system timers, disks IO, power-off signals, and traps. Other interrupts exist to transfer d...   » Read the article

Encyclopedia - Leap Second: Encyclopedia Ii - Leap Second - Announcement Of Leap Seconds
The announcement to insert a leap second is usually issued whenever the difference between UTC and UT1 approaches 0.7s, to keep the diffe...   » Read the article

Encyclopedia - Leap Second: Encyclopedia Ii - Leap Second - Proposal To Redefine Utc And Abolish Leap Seconds
On July 5, 2005, the Head of the Earth Orientation Center of the IERS sent a notice to IERS Bulletins C and D subscribers, soliciting com...   » Read the article

Encyclopedia - Hebrew Calendar: Encyclopedia Ii - Hebrew Calendar - Modern Calendar
Hebrew calendar - Epoch. The epoch of the modern Hebrew calendar is 1 Tishri AM 1 (AM = anno mundi = in the year of the world), which i...   » Read the article

Encyclopedia - Clock: Encyclopedia Ii - Clock - Types
There are two major types of clocks. Clock - Analog clocks. Analog clocks may be mechanical or have a quartz movement. A clock face is ...   » Read the article

Encyclopedia - Celestial Navigation: Encyclopedia Ii - Celestial Navigation - How It Works
Celestial navigation is the process whereby angles between objects in the sky (celestial objects) and the horizon are used to locate oneâ...   » Read the article

Encyclopedia - Celestial Navigation: Encyclopedia Ii - Celestial Navigation - Angular Measurement
Accurate angle measurement evolved over the years. One simple method is to hold the hand above the horizon with your arm stretched out. T...   » Read the article

Encyclopedia - Celestial Navigation: Encyclopedia Ii - Celestial Navigation - Modern Celestial Navigation
When the celestial line of position concept was discovered in 1837, it led later in the 19th century to the development of the modern int...   » Read the article

Encyclopedia - Clock: Encyclopedia Ii - Clock - Purposes
Clocks are in homes and offices; smaller ones (watches) are carried; larger ones are in public places, e.g. a train station or church. A ...   » Read the article

Encyclopedia - Maser: Encyclopedia Ii - Maser - Technology
The maser is based on the principle of stimulated emission proposed by Albert Einstein in 1917. When atoms have been put into an excited ...   » Read the article

Encyclopedia - Maser: Encyclopedia Ii - Maser - Astrophysical Masers
Stimulated microwave and radio wave emission is observed in astronomy, and this is usually called "masing", even in the absence of the re...   » Read the article

Encyclopedia - Music Radio: Encyclopedia Ii - Music Radio - Technology
While music radio, like all radio, started out on AM, it is somewhat unusual, at least in developed countries, to have a music station on...   » Read the article

Encyclopedia - Satellite Navigation System: Encyclopedia Ii - Satellite Navigation System - Civil And Military Uses
The original motivation for satellite navigation was for military applications. Satellite navigation allows for hitherto impossible preci...   » Read the article

Encyclopedia - Satellite Navigation System: Encyclopedia Ii - Satellite Navigation System - Current And Proposed Satellite Navigation Systems
Satellite navigation system - GPS. The best known satellite navigation system is the United States' Global Positioning System (GPS), an...   » Read the article

Encyclopedia - Transmitter: Encyclopedia Ii - Transmitter - Cooling Of Final Stages
Low-power transmitters do not require special cooling equipment. Modern transmitters can be incredibly efficient, with efficiencies excee...   » Read the article

Encyclopedia - Music Radio: Encyclopedia Ii - Music Radio - Programming By Time
Most music stations have DJs that play music from a playlist determined by the program director, arranged by blocks of time. Though pract...   » Read the article

Encyclopedia - Music Radio: Encyclopedia Ii - Music Radio - Types Of Program Segment
The classic item of music is a "single." This originally referred to a small phonograph disk played at 45RPM, with sufficient capacity to...   » Read the article

Encyclopedia - Maser: Encyclopedia Ii - Maser - Terminology
The meaning of the term maser has changed slightly since its introduction. Initially the acronym was universally given as "microwave ampl...   » Read the article

Encyclopedia - Maser: Encyclopedia Ii - Maser - Masers In Science Fiction
Masers are the most recognizable weapon in the Godzilla series and Toho's other monster movies. Maser tanks are often deployed against mo...   » Read the article

Encyclopedia - Music Radio: Encyclopedia Ii - Music Radio - How It Works
Music radio - Cost of programming. Stations usually adopt a music format to gain the greatest number of listeners for the least expense...   » Read the article

Encyclopedia - Transmitter: Encyclopedia Ii - Transmitter - Protection Equipment
The high voltages used in high power transmitters (up to 20 kV) require extensive protection equipment. Also, transmitters are exposed to...   » Read the article