|
Pendulum Instruments
{{primary sources, date=July 2012 Pendulum Instruments is a line of scientific instruments for high-resolution time and frequency measurements. Pendulum was originally created in the 1960s as the Philips time and frequency competence center. After 30 years of existence within Philips, it was spun off from 1998 but continued to sell Philips-branded instruments for another two years before starting to sell instruments under its own brand name. A Russian subsidiary was established in 2004, and in 2005, XL Microwave (an Oakland, CA-based manufacturer of microwave frequency counters and similar equipment) was acquired and transformed into the US branch ''Pendulum Instruments, Inc''. In 2008, Pendulum became part of the Orolia Group, and in 2009 its operations were combined with another Orolia company, Spectracom to form one global time & frequency systems & services organization operating under the Spectracom umbrella.Euronext news, "Orolia Advances Growth Strategy" http://ww ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Measuring Instrument
A measuring instrument is a device to measure a physical quantity. In the physical sciences, quality assurance, and engineering, measurement is the activity of obtaining and comparing physical quantities of real-world objects and events. Established standard objects and events are used as units, and the process of measurement gives a number relating the item under study and the referenced unit of measurement. Measuring instruments, and formal test methods which define the instrument's use, are the means by which these relations of numbers are obtained. All measuring instruments are subject to varying degrees of instrument error and measurement uncertainty. These instruments may range from simple objects such as rulers and stopwatches to electron microscopes and particle accelerators. Virtual instrumentation is widely used in the development of modern measuring instruments. Time In the past, a common time measuring instrument was the sundial. Today, the usual measuring instrum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal
A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macroscopic single crystals are usually identifiable by their geometrical shape, consisting of flat faces with specific, characteristic orientations. The scientific study of crystals and crystal formation is known as crystallography. The process of crystal formation via mechanisms of crystal growth is called crystallization or solidification. The word ''crystal'' derives from the Ancient Greek word (), meaning both "ice" and "rock crystal", from (), "icy cold, frost". Examples of large crystals include snowflakes, diamonds, and table salt. Most inorganic solids are not crystals but polycrystals, i.e. many microscopic crystals fused together into a single solid. Polycrystals include most metals, rocks, ceramics, and ice. A third category of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synchronization
Synchronization is the coordination of events to operate a system in unison. For example, the conductor of an orchestra keeps the orchestra synchronized or ''in time''. Systems that operate with all parts in synchrony are said to be synchronous or ''in sync''—and those that are not are '' asynchronous''. Today, time synchronization can occur between systems around the world through satellite navigation signals and other time and frequency transfer techniques. Navigation and railways Time-keeping and synchronization of clocks is a critical problem in long-distance ocean navigation. Before radio navigation and satellite-based navigation, navigators required accurate time in conjunction with astronomical observations to determine how far east or west their vessel traveled. The invention of an accurate marine chronometer revolutionized marine navigation. By the end of the 19th century, important ports provided time signals in the form of a signal gun, flag, or dropping time ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Fibre
An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means to transmit light between the two ends of the fiber and find wide usage in fiber-optic communications, where they permit transmission over longer distances and at higher bandwidths (data transfer rates) than electrical cables. Fibers are used instead of metal wires because signals travel along them with less loss; in addition, fibers are immune to electromagnetic interference, a problem from which metal wires suffer. Fibers are also used for illumination and imaging, and are often wrapped in bundles so they may be used to carry light into, or images out of confined spaces, as in the case of a fiberscope. Specially designed fibers are also used for a variety of other applications, some of them being fiber optic sensors and fiber lasers. Op ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coaxial Cable
Coaxial cable, or coax (pronounced ) is a type of electrical cable consisting of an inner conductor surrounded by a concentric conducting shield, with the two separated by a dielectric ( insulating material); many coaxial cables also have a protective outer sheath or jacket. The term ''coaxial'' refers to the inner conductor and the outer shield sharing a geometric axis. Coaxial cable is a type of transmission line, used to carry high-frequency electrical signals with low losses. It is used in such applications as telephone trunk lines, broadband internet networking cables, high-speed computer data busses, cable television signals, and connecting radio transmitters and receivers to their antennas. It differs from other shielded cables because the dimensions of the cable and connectors are controlled to give a precise, constant conductor spacing, which is needed for it to function efficiently as a transmission line. Coaxial cable was used in the first (1858) and followin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency Reference
A frequency standard is a stable oscillator used for frequency calibration or reference. A frequency standard generates a fundamental frequency with a high degree of accuracy and precision. Harmonics of this fundamental frequency are used to provide reference points. Since time is the reciprocal of frequency, it is relatively easy to derive a time standard from a frequency standard. A standard clock comprises a frequency standard, a device to count off the cycles of the oscillation emitted by the frequency standard, and a means of displaying or outputting the result. Frequency standards in a network or facility are sometimes administratively designated as ''primary'' or ''secondary''. The terms ''primary'' and ''secondary'', as used in this context, should not be confused with the respective technical meanings of these words in the discipline of precise time and frequency. Frequency reference A frequency reference is an instrument used for providing a stable frequency of some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency Counter
A frequency counter is an electronic instrument, or component of one, that is used for measuring frequency. Frequency counters usually measure the number of cycles of oscillation, or pulses per second in a periodic electronic signal. Such an instrument is sometimes referred to as a cymometer, particularly one of Chinese manufacture. Operating principle Most frequency counters work by using a counter which accumulates the number of events occurring within a specific period of time. After a preset period known as the ''gate time'' (1 second, for example), the value in the counter is transferred to a display and the counter is reset to zero. If the event being measured repeats itself with sufficient stability and the frequency is considerably lower than that of the clock oscillator being used, the resolution of the measurement can be greatly improved by measuring the time required for an entire number of cycles, rather than counting the number of entire cycles observed for a pre-set ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium
Rubidium is the chemical element with the symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope 85Rb, and 28% is slightly radioactive 87Rb, with a half-life of 48.8 billion years—more than three times as long as the estimated age of the universe. German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed technique, flame spectroscopy. The name comes from the Latin word , meaning deep red, the color of its emission spectrum. Rubidium's compounds have various chemical and electronic applications. Rubidium metal is easily vaporized and has a convenient spectral absorption range, making it a frequent target for laser manipulation of atoms. Rubidium is not a known nutrient for any living organisms. However, r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OCXO
A crystal oven is a temperature-controlled chamber used to maintain the quartz crystal in electronic crystal oscillators at a constant temperature, in order to prevent changes in the frequency due to variations in ambient temperature. An oscillator of this type is known as an ''oven-controlled crystal oscillator'' (OCXO, where "XO" is an old abbreviation for "crystal oscillator".) This type of oscillator achieves the highest frequency stability possible with a crystal. They are typically used to control the frequency of radio transmitters, cellular base stations, military communications equipment, and for precision frequency measurement. Description Quartz crystals are widely used in electronic oscillators to precisely control the frequency produced. The frequency at which a quartz crystal resonator vibrates depends on its physical dimensions. A change in temperature causes the quartz to expand or contract due to thermal expansion, changing the frequency of the signal produce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agilent Technologies
Agilent Technologies, Inc. is an American life sciences company that provides instruments, software, services, and consumables for the entire laboratory workflow. Its global headquarters is located in Santa Clara, California. Agilent was established in 1999 as a spin-off from Hewlett-Packard. The resulting IPO of Agilent stock was the largest in the history of Silicon Valley at the time. Agilent focuses its products and services on six markets: food, environmental and forensics, pharmaceutical, diagnostics, chemicals and advanced materials, and research. From 1999 to 2014, the company also produced test and measurement equipment for electronics; that division was spun off to form Keysight. Products and services Agilent serves analytical laboratories and the clinical and routine diagnostics markets with a full suite of technology platforms. These include: automation, bioreagents, FISH probes, gas and liquid chromatography, immunohistochemistry, informatics, mass spectrometry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time
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 addre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluke Corporation
Fluke Corporation is a manufacturer of industrial test, measurement, and diagnostic equipment including electronic test equipment. It was started in 1948 by John Fluke while he was employed at General Electric. History Fluke Corporation was founded by John Fluke in October 1953 as the John Fluke Manufacturing Company, Inc., producing electrical metering equipment. In 1987, Fluke partnered with the Dutch electronics manufacturer Philips. Together, the companies developed the scopemeter, an instrument combining features of an oscilloscope and a multimeter. Fluke purchased the testing and measurements division of Philips in 1993 for $41.8 million. The Philips PM series of measurement instruments was rebranded as Fluke. Fluke was bought by the Danaher Corporation in 1998. Danaher spun off several subsidiaries, including Fluke, in 2016 to create Fortive. Subsidiaries Pomona Electronics Pomona Electronics is a company specializing in electronic test equipment and accessorie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpeg/1200px-Space_Aggressors_test_Red_Flag_Airmen_(2743147).jpeg "Click for more on -> Agilent Technologies")
