Topic: Electronics (Page 3)

You are looking at all articles with the topic "Electronics". We found 37 matches.

Hint: To view all topics, click here. Too see the most popular topics, click here instead.

πŸ”— Claude Shannon

πŸ”— United States πŸ”— Biography πŸ”— Computer science πŸ”— Telecommunications πŸ”— Systems πŸ”— Biography/science and academia πŸ”— Cryptography πŸ”— Cryptography/Computer science πŸ”— Electronics πŸ”— Systems/Systems theory πŸ”— Telecommunications/Bell System πŸ”— Cycling

Claude Elwood Shannon (April 30, 1916 – February 24, 2001) was an American mathematician, electrical engineer, and cryptographer known as "the father of information theory". Shannon is noted for having founded information theory with a landmark paper, "A Mathematical Theory of Communication", that he published in 1948.

He is also well known for founding digital circuit design theory in 1937, whenβ€”as a 21-year-old master's degree student at the Massachusetts Institute of Technology (MIT)β€”he wrote his thesis demonstrating that electrical applications of Boolean algebra could construct any logical numerical relationship. Shannon contributed to the field of cryptanalysis for national defense during World War II, including his fundamental work on codebreaking and secure telecommunications.

Discussed on

πŸ”— Ferrite Bead

πŸ”— Technology πŸ”— Electronics πŸ”— Electrical engineering

A ferrite bead (also known as a ferrite block, ferrite core, ferrite ring, EMI filter, or ferrite choke) is a type of choke that suppresses high-frequency electronic noise in electronic circuits.

Ferrite beads employ high-frequency current dissipation in a ferrite ceramic to build high-frequency noise suppression devices.

Discussed on

πŸ”— Surface-conduction electron-emitter display

πŸ”— Computing πŸ”— Television πŸ”— Electronics

A surface-conduction electron-emitter display (SED) is a display technology for flat panel displays developed by a number of companies. SEDs use nanoscopic-scale electron emitters to energize colored phosphors and produce an image. In a general sense, an SED consists of a matrix of tiny cathode ray tubes, each "tube" forming a single sub-pixel on the screen, grouped in threes to form red-green-blue (RGB) pixels. SEDs combine the advantages of CRTs, namely their high contrast ratios, wide viewing angles and very fast response times, with the packaging advantages of LCD and other flat panel displays. They also use much less power than an LCD television of the same size.

After considerable time and effort in the early and mid-2000s, SED efforts started winding down in 2009 as LCD became the dominant technology. In August 2010, Canon announced they were shutting down their joint effort to develop SEDs commercially, signalling the end of development efforts. SEDs are closely related to another developing display technology, the field emission display, or FED, differing primarily in the details of the electron emitters. Sony, the main backer of FED, has similarly backed off from their development efforts.

Discussed on

πŸ”— Trancitor

πŸ”— Electronics πŸ”— Electrical engineering

The trancitor as the combined word of a "transfer-capacitor" is to be considered as another active-device category besides the transistor as a "transfer-resistor". As observed in the table shown, four kinds of active devices are theoretically deduced. Among them, trancitors are missing to be the third and fourth kinds, whereas transistors, such as bipolar junction transistor (BJT) and field-effect transistor (FET), were already invented as the first and second kinds, respectively. Unlike the transistor switching the current at its output (i.e., current source), the trancitor transfers its input to the voltage output (i.e., voltage source), so an inverse relationship with each other.

Discussed on

πŸ”— Electromagnetically Induced Acoustic Noise

πŸ”— Physics πŸ”— Electronics

Electromagnetically induced acoustic noise (and vibration), electromagnetically excited acoustic noise, or more commonly known as coil whine, is audible sound directly produced by materials vibrating under the excitation of electromagnetic forces. Some examples of this noise include the mains hum, hum of transformers, the whine of some rotating electric machines, or the buzz of fluorescent lamps. The hissing of high voltage transmission lines is due to corona discharge, not magnetism.

The phenomenon is also called audible magnetic noise, electromagnetic acoustic noise, lamination vibration or electromagnetically induced acoustic noise, or more rarely, electrical noise, or "coil noise", depending on the application. The term electromagnetic noise is generally avoided as the term is used in the field of electromagnetic compatibility, dealing with radio frequencies. The term electrical noise describes electrical perturbations occurring in electronic circuits, not sound. For the latter use, the terms electromagnetic vibrations or magnetic vibrations, focusing on the structural phenomenon are less ambiguous.

Acoustic noise and vibrations due to electromagnetic forces can be seen as the reciprocal of microphonics, which describes how a mechanical vibration or acoustic noise can induce an undesired electrical perturbation.

Discussed on

πŸ”— Wire wrap

πŸ”— Electronics

Wire wrap was invented to wire telephone crossbar switches, and later adapted to construct electronic circuit boards. Electronic components mounted on an insulating board are interconnected by lengths of insulated wire run between their terminals, with the connections made by wrapping several turns of uninsulated sections of the wire around a component lead or a socket pin.

Wires can be wrapped by hand or by machine, and can be hand-modified afterwards. It was popular for large-scale manufacturing in the 1960s and early 1970s, and continues today to be used for short runs and prototypes. The method eliminates the design and fabrication of a printed circuit board. Wire wrapping is unusual among other prototyping technologies since it allows for complex assemblies to be produced by automated equipment, but then easily repaired or modified by hand.

Wire wrap construction can produce assemblies which are more reliable than printed circuits: connections are less prone to fail due to vibration or physical stresses on the base board, and the lack of solder precludes soldering faults such as corrosion, cold joints and dry joints. The connections themselves are firmer and have lower electrical resistance due to cold welding of the wire to the terminal post at the corners.

Wire wrap was used for assembly of high frequency prototypes and small production runs, including gigahertz microwave circuits and supercomputers. It is unique among automated prototyping techniques in that wire lengths can be exactly controlled, and twisted pairs or magnetically shielded twisted quads can be routed together.

Wire wrap construction became popular around 1960 in circuit board manufacturing, and use has now sharply declined. Surface-mount technology has made the technique much less useful than in previous decades. Solder-less breadboards and the decreasing cost of professionally made PCBs have nearly eliminated this technology.

Discussed on

πŸ”— List of sensors

πŸ”— Technology πŸ”— Lists πŸ”— Electronics

This is a list of sensors sorted by sensor type.

Discussed on

πŸ”— Thyratron

πŸ”— Electronics πŸ”— Electrical engineering

A thyratron is a type of gas-filled tube used as a high-power electrical switch and controlled rectifier. Thyratrons can handle much greater currents than similar hard-vacuum tubes. Electron multiplication occurs when the gas becomes ionized, producing a phenomenon known as a Townsend discharge. Gases used include mercury vapor, xenon, neon, and (in special high-voltage applications or applications requiring very short switching times) hydrogen. Unlike a vacuum tube (valve), a thyratron cannot be used to amplify signals linearly.

In the 1920s, thyratrons were derived from early vacuum tubes such as the UV-200, which contained a small amount of argon gas to increase its sensitivity as a radio signal detector, and the German LRS relay tube, which also contained argon gas. Gas rectifiers, which predated vacuum tubes, such as the argon-filled General Electric "Tungar bulb" and the Cooper-Hewitt mercury-pool rectifier, also provided an influence. Irving Langmuir and G. S. Meikle of GE are usually cited as the first investigators to study controlled rectification in gas tubes, about 1914. The first commercial thyratrons appeared circa 1928.

The term "thyratron" is derived from Ancient Greek "θύρα" ("thyra"), meaning "door" or "valve". The term "thyristor" was further derived from a combination of "thyratron" and "transistor". Since the 1960s thyristors have replaced thyratrons in most low- and medium-power applications.

Discussed on

πŸ”— Muntzing

πŸ”— Technology πŸ”— Electronics πŸ”— Engineering πŸ”— Industrial design

Muntzing is the practice and technique of reducing the components inside an electronic appliance to the minimum required for it to sufficiently function in most operating conditions, reducing design margins above minimum requirements toward zero. The term is named after the man who invented it, Earl "Madman" Muntz, a car and electronics salesman, who was not formally educated or trained in any science or engineering discipline.

In the 1940s and 1950s, television receivers were relatively new to the consumer market, and were more complex pieces of equipment than the radios which were then in popular use. TVs often contained upwards of 30 vacuum tubes, as well as transformers, rheostats, and other electronics. The consequence of high cost was high sales pricing, limiting potential for high-volume sales. Muntz expressed suspicion of complexity in circuit designs, and determined through simple trial and error that he could remove a significant number of electronic components from a circuit design and still end up with a monochrome TV that worked sufficiently well in urban areas, close to transmission towers where the broadcast signal was strong. He carried a pair of wire clippers, and when he felt that one of his builders was overengineering a circuit, he would begin snipping out some of the electronics components. When the TV stopped functioning, he would have the technician reinsert the last removed part. He would repeat the snipping in other portions of the circuit until he was satisfied in his simplification efforts, and then leave the TV as it was without further testing in more adverse conditions for signal reception.

As a result, he reduced his costs and increased his profits at the expense of poorer performance at locations more distant from urban centers. He reasoned that population density was higher in and near the urban centers where the TVs would work, and lower further out where the TVs would not work, so the Muntz TVs were adequate for a very large fraction of his customers. And for those further out, where the Muntz TVs did not work, those could be returned at the customer's additional effort and expense, and not Muntz's. He focused less resources in the product, intentionally accepting bare minimum performance quality, and focused more resources on advertising and sales promotions.

Discussed on

πŸ”— Up to date list of departures & closures at Sun

πŸ”— California πŸ”— Companies πŸ”— Technology πŸ”— California/San Francisco Bay Area πŸ”— Computing πŸ”— Computing/Computer hardware πŸ”— Computing/Software πŸ”— Electronics

The acquisition of Sun Microsystems by Oracle Corporation was completed on January 27, 2010. Significantly, Oracle, previously only a software vendor, now owned both hardware and software product lines from Sun (e.g. SPARC Enterprise and Java, respectively).

A major issue of the purchase was that Sun was a major competitor to Oracle, raising many concerns among antitrust regulators, open source advocates, customers, and employees. The EU Commission delayed the acquisition for several months over concerns of Oracle's plans for MySQL, Sun's competitor to the Oracle Database. The commission finally approved the takeover, apparently pressured by the United States to do so, according to a WikiLeaks cable released in September 2011.

Discussed on