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Wien Bridge Oscillator
A Wien bridge oscillator is a type of electronic oscillator that generates sine waves. It can generate a large range of frequencies. The oscillator is based on a bridge circuit originally developed by Max Wien in 1891 for the measurement of impedances. The bridge comprises four resistors and two capacitors. The oscillator can also be viewed as a positive gain amplifier combined with a bandpass filter that provides positive feedback. Automatic gain control, intentional non-linearity and incidental non-linearity limit the output amplitude in various implementations of the oscillator. The circuit shown to the right depicts a once-common implementation of the oscillator, with automatic gain control using an incandescent lamp. Under the condition that R1=R2=R and C1=C2=C, the frequency of oscillation is given by: f_=\frac and the condition of stable oscillation is given by R_b = \frac Background There were several efforts to improve oscillators in the 1930s. Linearity was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wien Bridge Oscillator
A Wien bridge oscillator is a type of electronic oscillator that generates sine waves. It can generate a large range of frequencies. The oscillator is based on a bridge circuit originally developed by Max Wien in 1891 for the measurement of impedances. The bridge comprises four resistors and two capacitors. The oscillator can also be viewed as a positive gain amplifier combined with a bandpass filter that provides positive feedback. Automatic gain control, intentional non-linearity and incidental non-linearity limit the output amplitude in various implementations of the oscillator. The circuit shown to the right depicts a once-common implementation of the oscillator, with automatic gain control using an incandescent lamp. Under the condition that R1=R2=R and C1=C2=C, the frequency of oscillation is given by: f_=\frac and the condition of stable oscillation is given by R_b = \frac Background There were several efforts to improve oscillators in the 1930s. Linearity was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David Packard
David Packard ( ; September 7, 1912 – March 26, 1996) was an American electrical engineer and co-founder, with Bill Hewlett, of Hewlett-Packard (1939), serving as president (1947–64), CEO (1964–68), and chairman of the board (1964–68, 1972–93) of HP. He served as U.S. Deputy Secretary of Defense from 1969 to 1971 during the Nixon administration. Packard served as president of the Uniformed Services University of the Health Sciences (USU) from 1976 to 1981 and chairman of its board of regents from 1973 to 1982. He was a member of the Trilateral Commission. Packard was the recipient of the Presidential Medal of Freedom in 1988 and is noted for many technological innovations and philanthropic endeavors. Personal life Packard was born in Pueblo, Colorado, the son of Ella (Graber) and Sperry Sidney Packard, an attorney. He attended Centennial High School, where early on he showed an interest in science, engineering, sports, and leadership. Packard earned his B.A. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clipping (signal Processing)
Clipping is a form of distortion that limits a signal once it exceeds a threshold. Clipping may occur when a signal is recorded by a sensor that has constraints on the range of data it can measure, it can occur when a signal is digitized, or it can occur any other time an analog or digital signal is transformed, particularly in the presence of gain or overshoot and undershoot. Clipping may be described as hard, in cases where the signal is strictly limited at the threshold, producing a flat cutoff; or it may be described as soft, in cases where the clipped signal continues to follow the original at a reduced gain. Hard clipping results in many high-frequency harmonics; soft clipping results in fewer higher-order harmonics and intermodulation distortion components. Audio In the frequency domain, clipping produces strong harmonics in the high-frequency range (as the clipped waveform comes closer to a squarewave). The extra high-frequency weighting of the signal could mak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loop Gain
In electronics and control system theory, loop gain is the sum of the gain, expressed as a ratio or in decibels, around a feedback loop. Feedback loops are widely used in electronics in amplifiers and oscillators, and more generally in both electronic and nonelectronic industrial control systems to control industrial plant and equipment. The concept is also used in biology. In a feedback loop, the output of a device, process or plant is sampled and applied to alter the input, to better control the output. The loop gain, along with the related concept of loop phase shift, determines the behavior of the device, and particularly whether the output is stable, or unstable, which can result in oscillation. The importance of loop gain as a parameter for characterizing electronic feedback amplifiers was first recognized by Heinrich Barkhausen in 1921, and was developed further by Hendrik Wade Bode and Harry Nyquist at Bell Labs in the 1930s. A block diagram of an electronic a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Redington Hewlett
William Redington Hewlett ( ; May 20, 1913 – January 12, 2001) was an American engineer and the co-founder, with David Packard, of the Hewlett-Packard Company (HP). Early life and education Hewlett was born in Ann Arbor, Michigan, where his father taught at the University of Michigan Medical School. In 1916 the family moved to San Francisco after his father, Albion Walter Hewlett, took a similar position at Stanford Medical School, located at the time in San Francisco. He attended Lowell High School and was the 1929-1930 Battalion Commander of the school's Army JROTC program. He was accepted at Stanford University as a favor to his late father who had died of a brain tumor in 1925. Hewlett received his bachelor's degree from Stanford University in 1934, a Master of Science degree in electrical engineering from MIT in 1936, and the degree of Electrical Engineer from Stanford in 1939. He joined the Kappa Sigma fraternity during his time at Stanford. Career Hewlett-Packa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wien Bridge Oscillator Schematic From Hewletts US Patent
en, Viennese , iso_code = AT-9 , registration_plate = W , postal_code_type = Postal code , postal_code = , timezone = CET , utc_offset = +1 , timezone_DST = CEST , utc_offset_DST = +2 , blank_name = Vehicle registration , blank_info = W , blank1_name = GDP , blank1_info = € 96.5 billion (2020) , blank2_name = GDP per capita , blank2_info = € 50,400 (2020) , blank_name_sec1 = HDI (2019) , blank_info_sec1 = 0.947 · 1st of 9 , blank3_name = Seats in the Federal Council , blank3_info = , blank_name_sec2 = GeoTLD , blank_info_sec2 = .wien , website = , footnotes = , image_blank_emblem = Wien logo.svg , blank_emblem_size = Vienna ( ; german: Wien ; bar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Kilton Clapp
James Kilton Clapp (December 30, 1897 – 1965) was an American electrical engineer who worked for General Radio Corporation. He was born in Denver, Colorado and graduated from Massachusetts Institute of Technology in 1923, obtaining a master's degree there in 1926. He taught at MIT and then joined General Radio Corporation in 1928, until his retirement in 1957. He became a member of the IRE in 1928 and in 1933 was named "Fellow". Several of Clapp's inventions became the basis of General Radio products. He invented a quartz-crystal oscillator frequency standard in 1930, and patented a temperature control oven for crystal oscillators. Clapp's name is best known in the field of electronics for his description in 1948 of an improved form of Colpitts oscillator A Colpitts oscillator, invented in 1918 by American engineer Edwin H. Colpitts, is one of a number of designs for LC oscillators, electronic oscillators that use a combination of inductors (L) and capacitors (C) to produce an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheatstone Bridge
A Wheatstone bridge is an electrical circuit used to measure an unknown electrical resistance by balancing two legs of a bridge circuit, one leg of which includes the unknown component. The primary benefit of the circuit is its ability to provide extremely accurate measurements (in contrast with something like a simple voltage divider). Its operation is similar to the original potentiometer. The Wheatstone bridge was invented by Samuel Hunter Christie (sometimes spelled "Christy") in 1833 and improved and popularized by Sir Charles Wheatstone in 1843. One of the Wheatstone bridge's initial uses was for soil analysis and comparison."The Genesis of the Wheatstone Bridge" by Stig Ekelof discusses Christie's and Wheatstone's contributions, and why the bridge carries Wheatstone's name. Published in "Engineering Science and Education Journal", volume 10, no 1, February 2001, pages 37–40. Operation In the figure, is the fixed, yet unknown, resistance to be measured. and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taylor Series
In mathematics, the Taylor series or Taylor expansion of a function is an infinite sum of terms that are expressed in terms of the function's derivatives at a single point. For most common functions, the function and the sum of its Taylor series are equal near this point. Taylor series are named after Brook Taylor, who introduced them in 1715. A Taylor series is also called a Maclaurin series, when 0 is the point where the derivatives are considered, after Colin Maclaurin, who made extensive use of this special case of Taylor series in the mid-18th century. The partial sum formed by the first terms of a Taylor series is a polynomial of degree that is called the th Taylor polynomial of the function. Taylor polynomials are approximations of a function, which become generally better as increases. Taylor's theorem gives quantitative estimates on the error introduced by the use of such approximations. If the Taylor series of a function is convergent, its sum is the limit of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barkhausen Stability Criterion
In electronics, the Barkhausen stability criterion is a mathematical condition to determine when a linear electronic circuit will oscillate. It was put forth in 1921 by German physicist Heinrich Georg Barkhausen (1881–1956). It is widely used in the design of electronic oscillators, and also in the design of general negative feedback circuits such as op amps, to prevent them from oscillating. Limitations Barkhausen's criterion applies to linear circuits with a feedback loop. It cannot be applied directly to active elements with negative resistance like tunnel diode oscillators. The kernel of the criterion is that a complex pole pair must be placed on the imaginary axis of the complex frequency plane if steady state oscillations should take place. In the real world, it is impossible to balance on the imaginary axis, so in practice a steady-state oscillator is a non-linear circuit: * It needs to have positive feedback. * The loop gain is at unity (, \beta A, = 1\, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wien Bridge Oscillator With Diode Limiting
Vienna ( ; german: Wien ; bar, Wean, label=Bavarian language, Austro-Bavarian ) is the Capital city, capital, largest city, and one of States of Austria, nine states of Austria. Vienna is Austria's List of cities and towns in Austria, most populous city and its primate city, with about two million inhabitants (2.9 million within the metropolitan area, nearly one third of the country's population), and its Culture of Austria, cultural, Economy of Austria, economic, and Politics of Austria, political center. It is the Largest cities of the European Union by population within city limits, 6th-largest city proper by population in the European Union and the largest of all List of cities and towns on Danube river, cities on the Danube river. Until the beginning of the 20th century, Vienna was the largest German language, German-speaking city in the world, and before the splitting of the Austria-Hungary, Austro-Hungarian Empire in World War I, the city had two million inhabitants. To ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
